Toxins

17 pages, 5158 KiB

Open AccessArticle

Isolation and Functional Characterization of Erythrofibrase: An Alfa-Fibrinogenase Enzyme from Trimeresurus erythrurus Venom of North-East India

by Susmita Thakur, Rafika Yasmin, Anita Malhotra, Hmar Tlawmte Lalremsanga, Vishal Santra, Surajit Giri and Robin Doley

Toxins 2024, 16(4), 201; https://doi.org/10.3390/toxins16040201 - 22 Apr 2024

Viewed by 1490

Abstract

Green pit viper bites induce mild toxicity with painful local swelling, blistering, cellulitis, necrosis, ecchymosis and consumptive coagulopathy. Several bite cases of green pit vipers have been reported in several south-east Asian countries including the north-eastern region of India. The present study describes [...] Read more.

Green pit viper bites induce mild toxicity with painful local swelling, blistering, cellulitis, necrosis, ecchymosis and consumptive coagulopathy. Several bite cases of green pit vipers have been reported in several south-east Asian countries including the north-eastern region of India. The present study describes isolation and characterization of a haemostatically active protein from Trimeresurus erythrurus venom responsible for coagulopathy. Using a two-step chromatographic method, a snake venom serine protease erythrofibrase was purified to homogeneity. SDS-PAGE of erythrofibrase showed a single band of ~30 kDa in both reducing and non-reducing conditions. The primary structure of erythrofibrase was determined by ESI LC-MS/MS, and the partial sequence obtained showed 77% sequence similarity with other snake venom thrombin-like enzymes (SVTLEs). The partial sequence obtained had the typical 12 conserved cysteine residues, as well as the active site residues (His57, Asp102 and Ser195). Functionally, erythrofibrase showed direct fibrinogenolytic activity by degrading the Aα chain of bovine fibrinogen at a slow rate, which might be responsible for causing hypofibrinogenemia and incoagulable blood for several days in envenomated patients. Moreover, the inability of Indian polyvalent antivenom (manufactured by Premium Serum Pvt. Ltd., Maharashtra, India) to neutralize the thrombin-like and plasmin-like activity of erythrofibrase can be correlated with the clinical inefficacy of antivenom therapy. This is the first study reporting an α-fibrinogenase enzyme erythrofibrase from T. erythrurus venom, which is crucial for the pathophysiological manifestations observed in envenomated victims. Full article

(This article belongs to the Special Issue Venom Components Acting on the Hemostatic System: Structural and Mechanistic Insights)

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16 pages, 4575 KiB

Open AccessArticle

The Potential of Chitosan-Based Composites for Adsorption of Diarrheic Shellfish Toxins

by Joana F. Leal, Patrícia S. M. Amado, João P. Lourenço and Maria L. S. Cristiano

Toxins 2024, 16(4), 200; https://doi.org/10.3390/toxins16040200 - 21 Apr 2024

Viewed by 1413

Abstract

Okadaic acid (OA) is one of the most potent marine biotoxins, causing diarrheal shellfish poisoning (DSP). The proliferation of microalgae that produce OA and its analogues is frequent, threatening human health and socioeconomic development. Several methods have been tested to remove this biotoxin [...] Read more.

Okadaic acid (OA) is one of the most potent marine biotoxins, causing diarrheal shellfish poisoning (DSP). The proliferation of microalgae that produce OA and its analogues is frequent, threatening human health and socioeconomic development. Several methods have been tested to remove this biotoxin from aquatic systems, yet none has proven enough efficacy to solve the problem. In this work, we synthesized and characterized low-cost composites and tested their efficacy for OA adsorption in saltwater. For the synthesis of the composites, the following starting materials were considered: chitosan of low and medium molecular weight (CH-LW and CH-MW, respectively), activated carbon (AC), and montmorillonite (MMT). Characterization by vibrational spectroscopy (FTIR), X-ray diffraction (XRD), and microscopy revealed differences in the mode of interaction of CH-LW and CH-MW with AC and MMT, suggesting that the interaction of CH-MW with MMT has mainly occurred on the surface of the clay particles and no sufficient intercalation of CH-MW into the MMT interlayers took place. Among the composites tested (CH-LW/AC, CH-MW/AC, CH-MW/AC/MMT, and CH-MW/MMT), CH-MW/MMT was the one that revealed lower OA adsorption efficiency, given the findings evidenced by the structural characterization. On the contrary, the CH-MW/AC composite revealed the highest average percentage of OA adsorption (53 ± 11%). Although preliminary, the results obtained in this work open up good perspectives for the use of this type of composite material as an adsorbent in the removal of OA from marine environments. Full article

(This article belongs to the Section Marine and Freshwater Toxins)

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12 pages, 1299 KiB

Open AccessArticle

First Synthesis of Ergotamine-¹³CD₃ and Ergotaminine-¹³CD₃ from Unlabeled Ergotamine

by Sven-Oliver Herter, Hajo Haase and Matthias Koch

Toxins 2024, 16(4), 199; https://doi.org/10.3390/toxins16040199 - 20 Apr 2024

Viewed by 1383

Abstract

Ergot alkaloids (EAs) formed by Claviceps fungi are one of the most common food contaminants worldwide, affecting cereals such as rye, wheat, and barley. To accurately determine the level of contamination and to monitor EAs maximum levels set by the European Union, the [...] Read more.

Ergot alkaloids (EAs) formed by Claviceps fungi are one of the most common food contaminants worldwide, affecting cereals such as rye, wheat, and barley. To accurately determine the level of contamination and to monitor EAs maximum levels set by the European Union, the six most common EAs (so-called priority EAs) and their corresponding epimers are quantified using high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). The quantification of EAs in complex food matrices without appropriate internal standards is challenging but currently carried out in the standard method EN 17425:2021 due to their commercial unavailability. To address the need for isotopically labeled EAs, we focus on two semi-synthetic approaches for the synthesis of these reference standards. Therefore, we investigate the feasibility of the N⁶-demethylation of native ergotamine to yield norergotamine, which can subsequently be remethylated with an isotopically labeled methylating reagent, such as iodomethane (¹³CD₃-I), to yield isotopically labeled ergotamine and its C⁸-epimer ergotaminine. Testing the isotopically labeled ergotamine/-inine against native ergotamine/-inine with HPLC coupled to high-resolution HR-MS/MS proved the structure of ergotamine-¹³CD₃ and ergotaminine-¹³CD₃. Thus, for the first time, we can describe their synthesis from unlabeled, native ergotamine. Furthermore, this approach is promising as a universal way to synthesize other isotopically labeled EAs. Full article

(This article belongs to the Special Issue Detection, Control and Contamination of Mycotoxins (Volume II))

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33 pages, 1887 KiB

Open AccessReview

Analytical Methods for Anatoxin-a Determination: A Review

by Cristina Plata-Calzado, Ana I. Prieto, Ana M. Cameán and Angeles Jos

Toxins 2024, 16(4), 198; https://doi.org/10.3390/toxins16040198 - 19 Apr 2024

Cited by 1 | Viewed by 1604

Abstract

Anatoxin-a (ATX-a) is a potent neurotoxin produced by several species of cyanobacteria whose exposure can have direct consequences, including neurological disorders and death. The increasing prevalence of harmful cyanobacterial blooms makes the detection and reliable assessment of ATX-a levels essential to prevent the [...] Read more.

Anatoxin-a (ATX-a) is a potent neurotoxin produced by several species of cyanobacteria whose exposure can have direct consequences, including neurological disorders and death. The increasing prevalence of harmful cyanobacterial blooms makes the detection and reliable assessment of ATX-a levels essential to prevent the risk associated with public health. Therefore, the aim of this review is to compile the analytical methods developed to date for the detection and quantification of ATX-a levels alone and in mixtures with other cyanotoxins and their suitability. A classification of the analytical methods available is fundamental to make an appropriate choice according to the type of sample, the equipment available, and the required sensitivity and specificity for each specific purpose. The most widely used detection technique for the quantification of this toxin is liquid chromatography–tandem mass spectrometry (LC-MS/MS). The analytical methods reviewed herein focus mainly on water and cyanobacterial samples, so the need for validated analytical methods in more complex matrices (vegetables and fish) for the determination of ATX-a to assess dietary exposure to this toxin is evidenced. There is currently a trend towards the validation of multitoxin methods as opposed to single-ATX-a determination methods, which corresponds to the real situation of cyanotoxins’ confluence in nature. Full article

(This article belongs to the Special Issue Toxic Cyano Blooms around the World and Related Molecules)

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12 pages, 480 KiB

Open AccessArticle

Effectiveness of Extracorporeal Shock Wave Therapy after Botulinum Toxin Injection for Post-Stroke Upper Extremity Spasticity: A Randomized Controlled Study

by Junhee Lee and Seung Nam Yang

Toxins 2024, 16(4), 197; https://doi.org/10.3390/toxins16040197 - 19 Apr 2024

Cited by 1 | Viewed by 1656

Abstract

Post-stroke spasticity is a common complication that limits the functional performance of patients. Botulinum toxin (BTx) is an effective treatment for spasticity. Numerous researchers have applied extracorporeal shock wave therapy (ESWT) to address post-stroke spasticity, yielding positive clinical outcomes. We aimed to clarify [...] Read more.

Post-stroke spasticity is a common complication that limits the functional performance of patients. Botulinum toxin (BTx) is an effective treatment for spasticity. Numerous researchers have applied extracorporeal shock wave therapy (ESWT) to address post-stroke spasticity, yielding positive clinical outcomes. We aimed to clarify the add-on effects of ESWT on BTx therapy for spasticity in patients with post-stroke. Sixteen eligible patients with upper extremity spasticity after stroke were recruited for this study. They were randomized to either a BTx with focused ESWT treatment group or a BTx alone group. Spasticity, measured using the modified Ashworth score (MAS) and modified Tardieu scale (MTS), showed statistically significant improvements in the elbow and wrist flexor muscles in both BTx + ESWT group and BTx alone groups. However, no significant differences were observed between the two groups with time flow. The BTx + ESWT group showed significantly decreased MAS of the finger flexors at follow-up and increased R1 (MTS) of the finger flexors at 3 weeks after treatment, which was not observed in the BTx alone group. This is the first study to identify the add-on effect of ESWT on BTx injections to improve post-stroke upper limb spasticity. Full article

(This article belongs to the Special Issue Application of Botulinum Toxins in Diseases Treatment)

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18 pages, 1822 KiB

Open AccessEditor’s ChoiceReview

Microcystin Contamination in Irrigation Water and Health Risk

by Mohammed Haida, Fatima El Khalloufi, Richard Mugani, Yasser Essadki, Alexandre Campos, Vitor Vasconcelos and Brahim Oudra

Toxins 2024, 16(4), 196; https://doi.org/10.3390/toxins16040196 - 19 Apr 2024

Cited by 3 | Viewed by 2371

Abstract

Microcystins (MCs), natural hepatotoxic compounds produced by cyanobacteria, pose significant risks to water quality, ecosystem stability, and the well-being of animals, plants, and humans when present in elevated concentrations. The escalating contamination of irrigation water with MCs presents a growing threat to terrestrial [...] Read more.

Microcystins (MCs), natural hepatotoxic compounds produced by cyanobacteria, pose significant risks to water quality, ecosystem stability, and the well-being of animals, plants, and humans when present in elevated concentrations. The escalating contamination of irrigation water with MCs presents a growing threat to terrestrial plants. The customary practice of irrigating crops from local water sources, including lakes and ponds hosting cyanobacterial blooms, serves as a primary conduit for transferring these toxins. Due to their high chemical stability and low molecular weight, MCs have the potential to accumulate in various parts of plants, thereby increasing health hazards for consumers of agricultural products, which serve as the foundation of the Earth’s food chain. MCs can bioaccumulate, migrate, potentially biodegrade, and pose health hazards to humans within terrestrial food systems. This study highlights that MCs from irrigation water reservoirs can bioaccumulate and come into contact with plants, transferring into the food chain. Additionally, it investigates the natural mechanisms that organisms employ for conjugation and the microbial processes involved in MC degradation. To gain a comprehensive understanding of the role of MCs in the terrestrial food chain and to elucidate the specific health risks associated with consuming crops irrigated with water contaminated with these toxins, further research is necessary. Full article

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18 pages, 5205 KiB

Open AccessArticle

Overexpressing the cpr1953 Orphan Histidine Kinase Gene in the Absence of cpr1954 Orphan Histidine Kinase Gene Expression, or Vice Versa, Is Sufficient to Obtain Significant Sporulation and Strong Production of Clostridium perfringens Enterotoxin or Spo0A by Clostridium perfringens Type F Strain SM101

by Iman Mehdizadeh Gohari, Jessica L. Gonzales, Francisco A. Uzal and Bruce A. McClane

Toxins 2024, 16(4), 195; https://doi.org/10.3390/toxins16040195 - 18 Apr 2024

Cited by 1 | Viewed by 1387

Abstract

The CPR1953 and CPR1954 orphan histidine kinases profoundly affect sporulation initiation and Clostridium perfringens enterotoxin (CPE) production by C. perfringens type F strain SM101, whether cultured in vitro (modified Duncan–Strong sporulation medium (MDS)) or ex vivo (mouse small intestinal contents (MIC)). To help [...] Read more.

The CPR1953 and CPR1954 orphan histidine kinases profoundly affect sporulation initiation and Clostridium perfringens enterotoxin (CPE) production by C. perfringens type F strain SM101, whether cultured in vitro (modified Duncan–Strong sporulation medium (MDS)) or ex vivo (mouse small intestinal contents (MIC)). To help distinguish whether CPR1953 and CPR1954 act independently or in a stepwise manner to initiate sporulation and CPE production, cpr1953 and cpr1954 null mutants of SM101 were transformed with plasmids carrying the cpr1954 or cpr1953 genes, respectively, causing overexpression of cpr1954 in the absence of cpr1953 expression and vice versa. RT-PCR confirmed that, compared to SM101, the cpr1953 mutant transformed with a plasmid encoding cpr1954 expressed cpr1954 at higher levels while the cpr1954 mutant transformed with a plasmid encoding cpr1953 expressed higher levels of cpr1953. Both overexpressing strains showed near wild-type levels of sporulation, CPE toxin production, and Spo0A production in MDS or MIC. These findings suggest that CPR1953 and CPR1954 do not function together in a step-wise manner, e.g., as a novel phosphorelay. Instead, it appears that, at natural expression levels, the independent kinase activities of both CPR1953 and CPR1954 are necessary for obtaining sufficient Spo0A production and phosphorylation to initiate sporulation and CPE production. Full article

(This article belongs to the Special Issue Toxins: 15th Anniversary)

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13 pages, 4791 KiB

Open AccessArticle

Sortase-Modified Cholera Toxoids Show Specific Golgi Localization

by Darren C. Machin, Daniel J. Williamson, Peter Fisher, Victoria J. Miller, Zoe L. P. Arnott, Charlotte M. E. Stevenson, Gemma C. Wildsmith, James F. Ross, Christopher W. Wasson, Andrew Macdonald, Benjamin I. Andrews, Daniel Ungar, W. Bruce Turnbull and Michael E. Webb

Toxins 2024, 16(4), 194; https://doi.org/10.3390/toxins16040194 - 16 Apr 2024

Cited by 2 | Viewed by 1688

Abstract

Cholera toxoid is an established tool for use in cellular tracing in neuroscience and cell biology. We use a sortase labeling approach to generate site-specific N-terminally modified variants of both the A2-B₅ heterohexamer and B₅ pentamer forms of the toxoid. Both [...] Read more.

Cholera toxoid is an established tool for use in cellular tracing in neuroscience and cell biology. We use a sortase labeling approach to generate site-specific N-terminally modified variants of both the A2-B₅ heterohexamer and B₅ pentamer forms of the toxoid. Both forms of the toxoid are endocytosed by GM1-positive mammalian cells, and while the heterohexameric toxoid was principally localized in the ER, the B₅ pentamer showed an unexpectedly specific localization in the medial/trans-Golgi. This study suggests a future role for specifically labeled cholera toxoids in live-cell imaging beyond their current applications in neuronal tracing and labeling of lipid rafts in fixed cells. Full article

(This article belongs to the Special Issue Cholera Toxin)

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13 pages, 337 KiB

Open AccessArticle

Toxicity of Cry- and Vip3Aa-Class Proteins and Their Interactions against Spodoptera frugiperda (Lepidoptera: Noctuidae)

by Xiaobei Liu, Shen Liu, Shuxiong Bai, Kanglai He, Yongjun Zhang, Hui Dong, Tiantao Zhang and Zhenying Wang

Toxins 2024, 16(4), 193; https://doi.org/10.3390/toxins16040193 - 16 Apr 2024

Cited by 1 | Viewed by 1634

Abstract

The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), is one of the most important insect pests affecting corn crops worldwide. Although planting transgenic corn expressing Bacillus thuringiensis (Bt) toxins has been approved as being effective against FAW, its populations’ resistance to Bt crops [...] Read more.

The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith), is one of the most important insect pests affecting corn crops worldwide. Although planting transgenic corn expressing Bacillus thuringiensis (Bt) toxins has been approved as being effective against FAW, its populations’ resistance to Bt crops has emerged in different locations around the world. Therefore, it is important to understand the interaction between different Bt proteins, thereby delaying the development of resistance. In this study, we performed diet-overlay bioassays to evaluate the toxicity of Cry1Ab, Cry1Ac, Cry1B, Cry1Ca, Cry1F, Cry2Aa, Cry2Ab, Vip3Aa11, Vip3Aa19, and Vip3Aa20, as well as the interaction between Cry1Ab-, Cry1F-, Cry2Ab-, and Vip3Aa-class proteins against FAW. According to our results, the LC₅₀ values of Bt proteins varied from 12.62 ng/cm² to >9000 ng/cm² (protein/diet), among which the Vip3Aa class had the best insecticidal effect. The combination of Cry1Ab and Vip3Aa11 exhibited additive effects at a 5:1 ratio. Cry1F and Vip3Aa11 combinations exhibited additive effects at 1:1, 1:2, and 5:1 ratios. The combination of Cry1F and Vip3Aa19 showed an antagonistic effect when the ratio was 1:1 and an additive effect when the ratio was 1:2, 2:1, 1:5, and 5:1. Additionally, the combinations of Cry1F and Vip3Aa20 showed antagonistic effects at 1:2 and 5:1 ratios and additive effects at 1:1 and 2:1 ratios. In addition to the above combinations, which had additive or antagonistic effects, other combinations exhibited synergistic effects, with variations in synergistic factors (SFs). These results can be applied to the establishment of new pyramided transgenic crops with suitable candidates, providing a basis for FAW control and resistance management strategies. Full article

20 pages, 901 KiB

Open AccessReview

Antifungal Activity of Ribosome-Inactivating Proteins

by Rosario Iglesias, Lucía Citores, Claudia C. Gay and José M. Ferreras

Toxins 2024, 16(4), 192; https://doi.org/10.3390/toxins16040192 - 15 Apr 2024

Viewed by 1590

Abstract

The control of crop diseases caused by fungi remains a major problem and there is a need to find effective fungicides that are environmentally friendly. Plants are an excellent source for this purpose because they have developed defense mechanisms to cope with fungal [...] Read more.

The control of crop diseases caused by fungi remains a major problem and there is a need to find effective fungicides that are environmentally friendly. Plants are an excellent source for this purpose because they have developed defense mechanisms to cope with fungal infections. Among the plant proteins that play a role in defense are ribosome-inactivating proteins (RIPs), enzymes obtained mainly from angiosperms that, in addition to inactivating ribosomes, have been studied as antiviral, fungicidal, and insecticidal proteins. In this review, we summarize and discuss the potential use of RIPs (and other proteins with similar activity) as antifungal agents, with special emphasis on RIP/fungus specificity, possible mechanisms of antifungal action, and the use of RIP genes to obtain fungus-resistant transgenic plants. It also highlights the fact that these proteins also have antiviral and insecticidal activity, which makes them very versatile tools for crop protection. Full article

(This article belongs to the Special Issue Biological Activities of Ribosome Inactivating Proteins II)

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24 pages, 2358 KiB

Open AccessSystematic Review

Botulinum Toxin Injections for Psychiatric Disorders: A Systematic Review of the Clinical Trial Landscape

by Ilya Demchenko, Alyssa Swiderski, Helen Liu, Hyejung Jung, Wendy Lou and Venkat Bhat

Toxins 2024, 16(4), 191; https://doi.org/10.3390/toxins16040191 - 15 Apr 2024

Cited by 2 | Viewed by 3119

Abstract

Botulinum toxin type A (BONT-A) has shown promise in improving the mood-related symptoms of psychiatric disorders by targeting muscles linked to the expression of negative emotions. We conducted a systematic review of past and ongoing efficacy trials of BONT-A therapy for psychiatric disorders [...] Read more.

Botulinum toxin type A (BONT-A) has shown promise in improving the mood-related symptoms of psychiatric disorders by targeting muscles linked to the expression of negative emotions. We conducted a systematic review of past and ongoing efficacy trials of BONT-A therapy for psychiatric disorders to identify relevant trends in the field and discuss the refinement of therapeutic techniques. A comprehensive search for published clinical trials using BONT-A injections for psychiatric disorders was performed on 4 May 2023 through OVID databases (MEDLINE, Embase, APA PsycINFO). Unpublished clinical trials were searched through the ClinicalTrials.gov and International Clinical Trial Registry Platform public registries. The risk of bias was assessed using the JBI Critical Appraisal tools for use in systematic reviews. We identified 21 studies (17 published, 4 unpublished clinical trials) involving 471 patients. The studies focused on evaluating the efficacy of BONT-A for major depressive, borderline personality, social anxiety, and bipolar disorders. BONT-A was most commonly injected into the glabellar area, with an average dose ranging between 37.75 U and 44.5 U in published studies and between 32.7 U and 41.3 U in unpublished trials. The results indicated significant symptom reductions across all the studied psychiatric conditions, with mild adverse effects. Thus, BONT-A appears to be safe and well-tolerated for psychiatric disorders of negative affectivity. However, despite the clinical focus, there was a noted shortage of biomarker-related assessments. Future studies should focus on pursuing mechanistic explorations of BONT-A effects at the neurobiological level. Full article

(This article belongs to the Special Issue Uses of Botulinum Toxin Injection in Medicine)

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20 pages, 1119 KiB

Open AccessReview

Cyanobacteria and Macroinvertebrate Relationships in Freshwater Benthic Communities beyond Cytotoxicity

by Nicolás Ubero-Pascal and Marina Aboal

Toxins 2024, 16(4), 190; https://doi.org/10.3390/toxins16040190 - 15 Apr 2024

Cited by 1 | Viewed by 1585

Abstract

Cyanobacteria are harmful algae that are monitored worldwide to prevent the effects of the toxins that they can produce. Most research efforts have focused on direct or indirect effects on human populations, with a view to gain easy accurate detection and quantification methods, [...] Read more.

Cyanobacteria are harmful algae that are monitored worldwide to prevent the effects of the toxins that they can produce. Most research efforts have focused on direct or indirect effects on human populations, with a view to gain easy accurate detection and quantification methods, mainly in planktic communities, but with increasing interest shown in benthos. However, cyanobacteria have played a fundamental role from the very beginning in both the development of our planet’s biodiversity and the construction of new habitats. These organisms have colonized almost every possible planktic or benthic environment on earth, including the most extreme ones, and display a vast number of adaptations. All this explains why they are the most important or the only phototrophs in some habitats. The negative effects of cyanotoxins on macroinvertebrates have been demonstrated, but usually under conditions that are far from natural, and on forms of exposure, toxin concentration, or composition. The cohabitation of cyanobacteria with most invertebrate groups is long-standing and has probably contributed to the development of detoxification means, which would explain the survival of some species inside cyanobacteria colonies. This review focuses on benthic cyanobacteria, their capacity to produce several types of toxins, and their relationships with benthic macroinvertebrates beyond toxicity. Full article

(This article belongs to the Special Issue Editorial Board Members' Collection Series: Contribution of Information Technologies in Marine and Freshwater Toxins Research and Regulatory Practice)

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9 pages, 2030 KiB

Open AccessCommunication

First Detection of Algal Caribbean Ciguatoxin in Amberjack Causing Ciguatera Poisoning in the Canary Islands (Spain)

by Pablo Estevez, Juan Oses-Prieto, David Castro, Alejandro Penin, Alma Burlingame and Ana Gago-Martinez

Toxins 2024, 16(4), 189; https://doi.org/10.3390/toxins16040189 - 13 Apr 2024

Cited by 1 | Viewed by 1861

Abstract

Ciguatera Poisoning (CP) is an illness associated with the consumption of fish contaminated with potent natural toxins found in the marine environment, commonly known as ciguatoxins (CTXs). The risk characterization of CP has become a worldwide concern due to the widespread expansion of [...] Read more.

Ciguatera Poisoning (CP) is an illness associated with the consumption of fish contaminated with potent natural toxins found in the marine environment, commonly known as ciguatoxins (CTXs). The risk characterization of CP has become a worldwide concern due to the widespread expansion of these natural toxins. The identification of CTXs is hindered by the lack of commercially available reference materials. This limitation impedes progress in developing analytical tools and conducting toxicological studies essential for establishing regulatory levels for control. This study focuses on characterizing the CTX profile of an amberjack responsible for a recent CP case in the Canary Islands (Spain), located on the east Atlantic coast. The exceptional sensitivity offered by Capillary Liquid Chromatography coupled with High-Resolution Mass Spectrometry (cLC-HRMS) enabled the detection, for the first time in fish contaminated in the Canary Islands, of traces of an algal ciguatoxin recently identified in G. silvae and G. caribeaus from the Caribbean Sea. This algal toxin was structurally characterized by cLC-HRMS being initially identified as C-CTX5. The total toxin concentration of CTXs was eight times higher than the guidance level proposed by the Food and Drug Administration (0.1 ng C-CTX1/g fish tissue), with C-CTX1 and 17-hydroxy-C-CTX1 as major CTXs. Full article

(This article belongs to the Special Issue Advances in Marine Toxins: Characterization, Analysis and Surveillance)

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12 pages, 976 KiB

Open AccessArticle

Effect of Seaweed-Derived Fucoidans from Undaria pinnatifida and Fucus vesiculosus on Coagulant, Proteolytic, and Phospholipase A₂ Activities of Snake Bothrops jararaca, B. jararacussu, and B. neuwiedi Venom

by Camila Castro-Pinheiro, Luiz Carlos Simas Pereira Junior, Eladio Flores Sanchez, Ana Cláudia Rodrigues da Silva, Corinna A. Dwan, Samuel S. Karpiniec, Alan Trevor Critchley and Andre Lopes Fuly

Toxins 2024, 16(4), 188; https://doi.org/10.3390/toxins16040188 - 12 Apr 2024

Cited by 1 | Viewed by 1368

Abstract

Background: Snakebite envenomation (SBE) causes diverse toxic effects in humans, including disability and death. Current antivenom therapies effectively prevent death but fail to block local tissue damage, leading to an increase in the severity of envenomation; thus, seeking alternative treatments is crucial. Methods: [...] Read more.

Background: Snakebite envenomation (SBE) causes diverse toxic effects in humans, including disability and death. Current antivenom therapies effectively prevent death but fail to block local tissue damage, leading to an increase in the severity of envenomation; thus, seeking alternative treatments is crucial. Methods: This study analyzed the potential of two fucoidan sulfated polysaccharides extracted from brown seaweeds Fucus vesiculosus (FVF) and Undaria pinnatifida (UPF) against the fibrinogen or plasma coagulation, proteolytic, and phospholipase A₂ (PLA₂) activities of Bothrops jararaca, B. jararacussu, and B. neuwiedi venom. The toxicity of FVF and UPF was assessed by the hemocompatibility test. Results: FVF and UPF did not lyse human red blood cells. FVF and UPF inhibited the proteolytic activity of Bothrops jararaca, B. jararacussu, and B. neuwiedi venom by approximately 25%, 50%, and 75%, respectively, while all venoms led to a 20% inhibition of PLA₂ activity. UPF and FVF delayed plasma coagulation caused by the venoms of B. jararaca and B. neuwiedi but did not affect the activity of B. jararacussu venom. FVF and UPF blocked the coagulation of fibrinogen induced by all these Bothropic venoms. Conclusion: FVF and UPF may be of importance as adjuvants for SBE caused by species of Bothrops, which are the most medically relevant snakebite incidents in South America, especially Brazil. Full article

(This article belongs to the Special Issue Snake Venom: Toxicology and Associated Countermeasures)

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16 pages, 2336 KiB

Open AccessArticle

Molecular Aspects Involved in the Mechanisms of Bothrops jararaca Venom-Induced Hyperalgesia: Participation of NK1 Receptor and Glial Cells

by Ariela de Oliveira Pedro Bom, Monique Dias-Soares, Raíssa Cristina Darroz Corrêa, Camila Lima Neves, Natalia Gabriele Hosch, Gabriela Gomes de Lucena, Camilla Garcia Oliveira, Rosana Lima Pagano, Marucia Chacur and Renata Giorgi

Toxins 2024, 16(4), 187; https://doi.org/10.3390/toxins16040187 - 10 Apr 2024

Viewed by 1437

Abstract

Accidents caused by Bothrops jararaca (Bj) snakes result in several local and systemic manifestations, with pain being a fundamental characteristic. The inflammatory process responsible for hyperalgesia induced by Bj venom (Bjv) has been studied; however, the specific roles played by the peripheral and [...] Read more.

Accidents caused by Bothrops jararaca (Bj) snakes result in several local and systemic manifestations, with pain being a fundamental characteristic. The inflammatory process responsible for hyperalgesia induced by Bj venom (Bjv) has been studied; however, the specific roles played by the peripheral and central nervous systems in this phenomenon remain unclear. To clarify this, we induced hyperalgesia in rats using Bjv and collected tissues from dorsal root ganglia (DRGs) and spinal cord (SC) at 2 and 4 h post-induction. Samples were labeled for Iba-1 (macrophage and microglia), GFAP (satellite cells and astrocytes), EGR1 (neurons), and NK1 receptors. Additionally, we investigated the impact of minocycline, an inhibitor of microglia, and GR82334 antagonist on Bjv-induced hyperalgesia. Our findings reveal an increase in Iba1 in DRG at 2 h and EGR1 at 4 h. In the SC, markers for microglia, astrocytes, neurons, and NK1 receptors exhibited increased expression after 2 h, with EGR1 continuing to rise at 4 h. Minocycline and GR82334 inhibited venom-induced hyperalgesia, highlighting the crucial roles of microglia and NK1 receptors in this phenomenon. Our results suggest that the hyperalgesic effects of Bjv involve the participation of microglial and astrocytic cells, in addition to the activation of NK1 receptors. Full article

(This article belongs to the Section Animal Venoms)

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16 pages, 5141 KiB

Open AccessCommunication

Tetrodotoxins in Tissues and Cells of Different Body Regions of Ribbon Worms Kulikovia alborostrata and K. manchenkoi from Spokoynaya Bay, Sea of Japan

by Anna E. Vlasenko, Alexandra O. Pereverzeva, Peter V. Velansky and Timur Yu. Magarlamov

Toxins 2024, 16(4), 186; https://doi.org/10.3390/toxins16040186 - 10 Apr 2024

Viewed by 1074

Abstract

Nemerteans, or ribbon worms, possess tetrodotoxin and its analogues (TTXs), neurotoxins of bacterial origin, which they presumably use for capturing prey and self-defense. Most TTXs-containing nemertean species have low levels of these toxins and, therefore, have usually been neglected in studies of TTXs [...] Read more.

Nemerteans, or ribbon worms, possess tetrodotoxin and its analogues (TTXs), neurotoxins of bacterial origin, which they presumably use for capturing prey and self-defense. Most TTXs-containing nemertean species have low levels of these toxins and, therefore, have usually been neglected in studies of TTXs functions and accumulation. In the present study, Kulikovia alborostrata and K. manchenkoi, two closely related species, were analyzed for TTXs distribution in the body using the HPLC–MS/MS and fluorescence microscopy methods. The abundance of TTXs-positive cells was determined in the proboscis, integument, and digestive system epithelium. As a result, six TTXs-positive cell types were identified in each species; however, only four were common. Moreover, the proportions of the toxins in different body parts were estimated. According to the HPLC–MS/MS analysis, the TTXs concentrations in K. alborostrata varied from 0.91 ng/g in the proboscis to 5.52 ng/g in the precerebral region; in K. manchenkoi, the concentrations ranged from 7.47 ng/g in the proboscis to 72.32 ng/g in the posterior body region. The differences observed between the two nemerteans in the distribution of the TTXs were consistent with the differences in the localization of TTXs-positive cells. In addition, TTXs-positive glandular cell types were found in the intestine and characterized for the first time. TTXs in the new cell types were assumed to play a unique physiological role for nemerteans. Full article

(This article belongs to the Special Issue Advances in Marine Toxins: Characterization, Analysis and Surveillance)

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17 pages, 10327 KiB

Open AccessEditor’s ChoiceArticle

Edodin: A New Type of Toxin from Shiitake Mushroom (Lentinula edodes) That Inactivates Mammalian Ribosomes

by Lucía Citores, Sara Ragucci, Claudia C. Gay, Rosita Russo, Angela Chambery, Antimo Di Maro, Rosario Iglesias and José M. Ferreras

Toxins 2024, 16(4), 185; https://doi.org/10.3390/toxins16040185 - 10 Apr 2024

Viewed by 2149

Abstract

Ribosome-inactivating proteins (RIPs) are a group of proteins with rRNA N-glycosylase activity that irreversibly inhibit protein synthesis and consequently cause cell death. Recently, an RIP called ledodin has been found in shiitake; it is cytotoxic, strongly inhibits protein synthesis, and shows rRNA N-glycosylase [...] Read more.

Ribosome-inactivating proteins (RIPs) are a group of proteins with rRNA N-glycosylase activity that irreversibly inhibit protein synthesis and consequently cause cell death. Recently, an RIP called ledodin has been found in shiitake; it is cytotoxic, strongly inhibits protein synthesis, and shows rRNA N-glycosylase activity. In this work, we isolated and characterized a 50 kDa cytotoxic protein from shiitake that we named edodin. Edodin inhibits protein synthesis in a mammalian cell-free system, but not in insect-, yeast-, and bacteria-derived systems. It exhibits rRNA N-glycosylase and DNA-nicking activities, which relate it to plant RIPs. It was also shown to be toxic to HeLa and COLO 320 cells. Its structure is not related to other RIPs found in plants, bacteria, or fungi, but, instead, it presents the characteristic structure of the fold type I of pyridoxal phosphate-dependent enzymes. Homologous sequences have been found in other fungi of the class Agaricomycetes; thus, edodin could be a new type of toxin present in many fungi, some of them edible, which makes them of great interest in health, both for their involvement in food safety and for their potential biomedical and biotechnological applications. Full article

(This article belongs to the Special Issue Biological Activities of Ribosome Inactivating Proteins II)

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42 pages, 34187 KiB

Open AccessReview

The Role of Botulinum Toxin Type-A in Spasticity: Research Trends from a Bibliometric Analysis

by Salvatore Facciorusso, Stefania Spina, Alessandro Picelli, Alessio Baricich, Gerard E. Francisco, Franco Molteni, Jörg Wissel and Andrea Santamato

Toxins 2024, 16(4), 184; https://doi.org/10.3390/toxins16040184 - 9 Apr 2024

Cited by 3 | Viewed by 3142

Abstract

Botulinum toxin type-A (BoNT-A) has emerged as a key therapeutic agent for the management of spasticity. This paper presents a comprehensive bibliometric and visual analysis of research concerning BoNT-A treatment of spasticity to elucidate current trends and future directions in this research area. [...] Read more.

Botulinum toxin type-A (BoNT-A) has emerged as a key therapeutic agent for the management of spasticity. This paper presents a comprehensive bibliometric and visual analysis of research concerning BoNT-A treatment of spasticity to elucidate current trends and future directions in this research area. A search was conducted in the Web of Science database for articles focused on the use of BoNT-A in spasticity published between 2000 and 2022. We extracted various metrics, including counts of publications and contributions from different countries, institutions, authors, and journals. Analytical methods in CiteSpace were employed for the examination of co-citations, collaborations, and the co-occurrence of keywords. Our search yielded 1489 publications. Analysis revealed a consistent annual increase in research output. The United States, United Kingdom, and Italy were the leading contributors. The top institution in this research was Assistance Publique Hopitaux, Paris. The journal containing the highest number of relevant publications was Toxins. Key frequently occurring keywords were ‘stroke’, ‘cerebral palsy’, ‘adult spasticity’, and ‘upper extremity’. This study identified 12 clusters of keywords and 15 clusters of co-cited references, indicating the main focus areas and emerging themes in this field. This study comprehensively analyzed and summarized trends in BoNT-A research in the field of spasticity over the past 22 years. Full article

(This article belongs to the Special Issue The Botulinum Toxin and Spasticity: Exploring New Horizons)

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21 pages, 4265 KiB

Open AccessArticle

Standard Quality Characteristics and Efficacy of a New Third-Generation Antivenom Developed in Colombia Covering Micrurus spp. Venoms

by Santiago Tabares Vélez, Lina María Preciado, Leidy Johana Vargas Muñoz, Carlos Alberto Madrid Bracamonte, Angelica Zuluaga, Jeisson Gómez Robles, Camila Renjifo-Ibañez and Sebastián Estrada-Gómez

Toxins 2024, 16(4), 183; https://doi.org/10.3390/toxins16040183 - 9 Apr 2024

Viewed by 1876

Abstract

In Colombia, Micrurus snakebites are classified as severe according to the national clinical care guidelines and must be treated with specific antivenoms. Unfortunately, these types of antivenoms are scarce in certain areas of the country and are currently reported as an unavailable vital [...] Read more.

In Colombia, Micrurus snakebites are classified as severe according to the national clinical care guidelines and must be treated with specific antivenoms. Unfortunately, these types of antivenoms are scarce in certain areas of the country and are currently reported as an unavailable vital medicine. To address this issue, La Universidad de Antioquia, through its spin-off Tech Life Saving, is leading a project to develop third-generation polyvalent freeze-dried antivenom. The goal is to ensure access to this therapy, especially in rural and dispersed areas. This project aims to evaluate the physicochemical and preclinical parameters (standard quality characteristics) of a lab-scale anti-elapid antivenom batch. The antivenom is challenged against the venoms of several Micrurus species, including M. mipartitus, M. dumerilii, M. ancoralis, M. dissoleucus, M. lemniscatus, M. medemi, M. spixii, M. surinamensis, and M. isozonus, following the standard quality characteristics set by the World Health Organization (WHO). The antivenom demonstrates an appearance consistent with standards, 100% solubility within 4 min and 25 s, an extractable volume of 10.39 mL, a pH of 6.04, an albumin concentration of 0.377 mg/mL (equivalent to 1.22% of total protein), and a protein concentration of 30.97 mg/mL. Importantly, it maintains full integrity of its F(ab′)₂ fragments and exhibits purity over 98.5%. Furthermore, in mice toxicity evaluations, doses up to 15 mg/mouse show no toxic effects. The antivenom also demonstrates a significant recognition pattern against Micrurus venoms rich in phospholipase A₂ (PLA₂) content, as observed in M. dumerilii, M. dissoleucus, and M. isozonus. The effective dose 50 (ED₅₀) indicates that a single vial (10 mL) can neutralize 2.33 mg of M. mipartitus venom and 3.99 mg of M. dumerilii venom. This new anti-elapid third-generation polyvalent and freeze-dried antivenom meets the physicochemical parameters set by the WHO and the regulators in Colombia. It demonstrates significant efficacy in neutralizing the venom of the most epidemiologically important Micrurus species in Colombia. Additionally, it recognizes seven other species of Micrurus venom with a higher affinity for venoms exhibiting PLA₂ toxins. Fulfilling these parameters represents the first step toward proposing a new pharmacological alternative for treating snakebites in Colombia, particularly in dispersed rural areas, given that this antivenom is formulated as a freeze-dried product. Full article

(This article belongs to the Special Issue Pre-clinical and Clinical Management of Snakebite Envenomation)

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46 pages, 7856 KiB

Open AccessEditor’s ChoiceReview

Overview of Bacterial Protein Toxins from Pathogenic Bacteria: Mode of Action and Insights into Evolution

by Michel R. Popoff

Toxins 2024, 16(4), 182; https://doi.org/10.3390/toxins16040182 - 8 Apr 2024

Cited by 3 | Viewed by 5012

Abstract

Bacterial protein toxins are secreted by certain bacteria and are responsible for mild to severe diseases in humans and animals. They are among the most potent molecules known, which are active at very low concentrations. Bacterial protein toxins exhibit a wide diversity based [...] Read more.

Bacterial protein toxins are secreted by certain bacteria and are responsible for mild to severe diseases in humans and animals. They are among the most potent molecules known, which are active at very low concentrations. Bacterial protein toxins exhibit a wide diversity based on size, structure, and mode of action. Upon recognition of a cell surface receptor (protein, glycoprotein, and glycolipid), they are active either at the cell surface (signal transduction, membrane damage by pore formation, or hydrolysis of membrane compound(s)) or intracellularly. Various bacterial protein toxins have the ability to enter cells, most often using an endocytosis mechanism, and to deliver the effector domain into the cytosol, where it interacts with an intracellular target(s). According to the nature of the intracellular target(s) and type of modification, various cellular effects are induced (cell death, homeostasis modification, cytoskeleton alteration, blockade of exocytosis, etc.). The various modes of action of bacterial protein toxins are illustrated with representative examples. Insights in toxin evolution are discussed. Full article

(This article belongs to the Special Issue Toxins: 15th Anniversary)

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15 pages, 3266 KiB

Open AccessArticle

Studying Venom Toxin Variation Using Accurate Masses from Liquid Chromatography–Mass Spectrometry Coupled with Bioinformatic Tools

by Luis L. Alonso, Jory van Thiel, Julien Slagboom, Nathan Dunstan, Cassandra M. Modahl, Timothy N. W. Jackson, Saer Samanipour and Jeroen Kool

Toxins 2024, 16(4), 181; https://doi.org/10.3390/toxins16040181 - 7 Apr 2024

Viewed by 1785

Abstract

This study provides a new methodology for the rapid analysis of numerous venom samples in an automated fashion. Here, we use LC-MS (Liquid Chromatography–Mass Spectrometry) for venom separation and toxin analysis at the accurate mass level combined with new in-house written bioinformatic scripts [...] Read more.

This study provides a new methodology for the rapid analysis of numerous venom samples in an automated fashion. Here, we use LC-MS (Liquid Chromatography–Mass Spectrometry) for venom separation and toxin analysis at the accurate mass level combined with new in-house written bioinformatic scripts to obtain high-throughput results. This analytical methodology was validated using 31 venoms from all members of a monophyletic clade of Australian elapids: brown snakes (Pseudonaja spp.) and taipans (Oxyuranus spp.). In a previous study, we revealed extensive venom variation within this clade, but the data was manually processed and MS peaks were integrated into a time-consuming and labour-intensive approach. By comparing the manual approach to our new automated approach, we now present a faster and more efficient pipeline for analysing venom variation. Pooled venom separations with post-column toxin fractionations were performed for subsequent high-throughput venomics to obtain toxin IDs correlating to accurate masses for all fractionated toxins. This workflow adds another dimension to the field of venom analysis by providing opportunities to rapidly perform in-depth studies on venom variation. Our pipeline opens new possibilities for studying animal venoms as evolutionary model systems and investigating venom variation to aid in the development of better antivenoms. Full article

(This article belongs to the Special Issue Venomous Snakes: Taxonomy, Toxicology and Clinical Management of Envenomation)

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14 pages, 2539 KiB

Open AccessReview

The Molecular Architecture and Mode of Action of Clostridium perfringens ε-Toxin

by Richard W. Titball

Toxins 2024, 16(4), 180; https://doi.org/10.3390/toxins16040180 - 7 Apr 2024

Viewed by 2033

Abstract

Clostridium perfringens ε-toxin has long been associated with a severe enterotoxaemia of livestock animals, and more recently, was proposed to play a role in the etiology of multiple sclerosis in humans. The remarkable potency of the toxin has intrigued researchers for many decades, [...] Read more.

Clostridium perfringens ε-toxin has long been associated with a severe enterotoxaemia of livestock animals, and more recently, was proposed to play a role in the etiology of multiple sclerosis in humans. The remarkable potency of the toxin has intrigued researchers for many decades, who suggested that this indicated an enzymatic mode of action. Recently, there have been major breakthroughs by finding that it is a pore-forming toxin which shows exquisite specificity for cells bearing the myelin and lymphocyte protein (MAL) receptor. This review details the molecular structures of the toxin, the evidence which identifies MAL as the receptor and the possible roles of other cell membrane components in toxin binding. The information on structure and mode of action has allowed the functions of individual amino acids to be investigated and has led to the creation of mutants with reduced toxicity that could serve as vaccines. In spite of this progress, there are still a number of key questions around the mode of action of the toxin which need to be further investigated. Full article

(This article belongs to the Special Issue Toxin-Host Interaction of Clostridium Toxins)

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16 pages, 2934 KiB

Open AccessArticle

The Effect of Combined Exposure of Fusarium Mycotoxins on Lipid Peroxidation, Antioxidant Defense, Fatty Acid Profile, and Histopathology in Laying Hens’ Liver

by Szabina Kulcsár, Janka Turbók, György Kövér, Krisztián Balogh, Erika Zándoki, Patrik Gömbös, Omeralfaroug Ali, András Szabó and Miklós Mézes

Toxins 2024, 16(4), 179; https://doi.org/10.3390/toxins16040179 - 7 Apr 2024

Cited by 3 | Viewed by 1541

Abstract

Fumonisin B1, T-2 toxin, and deoxynivalenol are frequently detected in feed materials. The mycotoxins induce free radical formation and, thereby, lipid peroxidation. The effects of mycotoxin exposure at the EU recommended limit (T-2/HT-2 toxin: 0.25 mg/kg; DON = 3AcDON/15-AScDON: 5 mg/kg; fumonisin B1: [...] Read more.

Fumonisin B1, T-2 toxin, and deoxynivalenol are frequently detected in feed materials. The mycotoxins induce free radical formation and, thereby, lipid peroxidation. The effects of mycotoxin exposure at the EU recommended limit (T-2/HT-2 toxin: 0.25 mg/kg; DON = 3AcDON/15-AScDON: 5 mg/kg; fumonisin B1: 20 mg/kg) and double dose (T-2/HT-2 toxin: 0.5 mg/kg, DON/3-AcDON/15-AcDON: 10 mg, and FB1: 40 mg/kg feed) were investigated during short-term (3 days) per os exposure in the liver of laying hens. On day 1 higher while on day 3 lower MDA concentrations were found in the low-dose group compared to the control. Fatty acid composition also changed: the proportion of monounsaturated fatty acids increased (p < 0.05) and the proportion of polyunsaturated fatty acids decreased by day 3. These alterations resulted in a decrease in the index of unsaturation and average fatty acid chain length. Histopathological alterations suggested that the incidence and severity of liver lesions were higher in the mycotoxin-treated laying hens, and the symptoms correlated with the fatty acid profile of total phospholipids. Overall, the findings revealed that mycotoxin exposure, even at the EU-recommended limits, induced lipid peroxidation in the liver, which led to changes in fatty acid composition, matched with tissue damage. Full article

(This article belongs to the Special Issue Effects of Feedborne Mycotoxins on Animal Health 2.0)

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11 pages, 281 KiB

Open AccessArticle

Reducing the Impact of Headache and Allodynia Score in Chronic Migraine: An Exploratory Analysis from the Real-World Effectiveness of Anti-CGRP Monoclonal Antibodies Compared to Onabotulinum Toxin A (RAMO) Study

by Danilo Antonio Montisano, Riccardo Giossi, Mattia Canella, Claudia Altamura, Marilena Marcosano, Fabrizio Vernieri, Alberto Raggi and Licia Grazzi

Toxins 2024, 16(4), 178; https://doi.org/10.3390/toxins16040178 - 7 Apr 2024

Viewed by 1865

Abstract

Background: Chronic migraine (CM) is a disabling and hard-to-treat condition, associated with high disability and high cost. Among the preventive treatments, botulinum toxin A (BoNT-a) and monoclonal antibodies against the calcitonin gene-related protein (anti-CGRP mAbs) are the only disease-specific ones. The assessment of [...] Read more.

Background: Chronic migraine (CM) is a disabling and hard-to-treat condition, associated with high disability and high cost. Among the preventive treatments, botulinum toxin A (BoNT-a) and monoclonal antibodies against the calcitonin gene-related protein (anti-CGRP mAbs) are the only disease-specific ones. The assessment of the disease burden is complex, and among others, tools such as the allodynia symptoms checklist (ASC-12) and headache impact test (HIT-6) are very useful. This exploratory study analysed the impact of these two therapies on migraine burden. Methods: The RAMO study was a multicentre, observational, retrospective investigation conducted in two headache centres: the Fondazione IRCCS Istituto Neurologico Carlo Besta (Milan) and the Fondazione Policlinico Campus Bio-Medico (Rome). This study involved patients with chronic migraine treated with mAbs or BoNT-A. We conducted a subgroup exploratory analysis on HIT-6 and ASC-12 scores in the two groups. The Wilcoxon rank-sum test, Fisher’s exact test, and ANOVA were performed. Results: Of 126 patients, 36 on mAbs and 90 on BoNT-A had at least one available follow-up. mAbs resulted in a mean reduction of −11.1 and −11.4 points, respectively, in the HIT-6 at 6 and 12 months, while BoNT-A was reduced −3.2 and −3.6 points, respectively; the mAbs arm resulted in mean reductions in ASC-12 at 6 and 12 months of follow-up of −5.2 and −6.0 points, respectively, while BoNT-A showed lesser mean changes of −0.5 and −0.9 points, respectively. The adjusted analysis confirmed our results. Conclusions: In this exploratory analysis, anti-CGRP mAbs showed superior effectiveness for HIT-6 and ASC12 compared to BoNT-A. Reductions in terms of month headache days (MHD), migraine disability assessment test (MIDAS), and migraine acute medications (MAM) were clinically relevant for both treatments. Full article

(This article belongs to the Special Issue Botulinum Toxin and Migraine: Goals and Perspectives (Volume II))

14 pages, 3513 KiB

Open AccessArticle

Patulin Biodegradation Mechanism Study in Pichia guilliermondii S15-8 Based on PgSDR-A5D9S1

by Huijuan Xi, Yebo Wang, Xulei Ni, Minjie Zhang and Ying Luo

Toxins 2024, 16(4), 177; https://doi.org/10.3390/toxins16040177 - 4 Apr 2024

Viewed by 1464

Abstract

Patulin contamination has become a bottleneck problem in the safe production of fruit products, although biodegradation technology shows potential application value in patulin control. In the present study, the patulin biodegradation mechanism in a probiotic yeast, Pichia guilliermondii S15-8, was investigated. Firstly, the [...] Read more.

Patulin contamination has become a bottleneck problem in the safe production of fruit products, although biodegradation technology shows potential application value in patulin control. In the present study, the patulin biodegradation mechanism in a probiotic yeast, Pichia guilliermondii S15-8, was investigated. Firstly, the short-chain dehydrogenase PgSDR encoded by gene A5D9S1 was identified as a patulin degradation enzyme, through RNA sequencing and verification by qRT-PCR. Subsequently, the exogenous expression system of the degradation protein PgSDR-A5D9S1 in E. coli was successfully constructed and demonstrated a more significant patulin tolerance and degradation ability. Furthermore, the structure of PgSDR-A5D9S1 and its active binding sites with patulin were predicted via molecular docking analysis. In addition, the heat-excited protein HSF1 was predicted as the transcription factor regulating the patulin degradation protein PgSDR-A5D9S1, which may provide clues for the further analysis of the molecular regulation mechanism of patulin degradation. This study provides a theoretical basis and technical support for the industrial application of biodegradable functional strains. Full article

(This article belongs to the Section Mycotoxins)

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11 pages, 4216 KiB

Open AccessEditor’s ChoiceArticle

High-Voltage Toxin’Roll: Electrostatic Charge Repulsion as a Dynamic Venom Resistance Trait in Pythonid Snakes

by Uthpala Chandrasekara, Emilie M. Broussard, Darin R. Rokyta and Bryan G. Fry

Toxins 2024, 16(4), 176; https://doi.org/10.3390/toxins16040176 - 4 Apr 2024

Viewed by 2194

Abstract

The evolutionary interplay between predator and prey has significantly shaped the development of snake venom, a critical adaptation for subduing prey. This arms race has spurred the diversification of the components of venom and the corresponding emergence of resistance mechanisms in the prey [...] Read more.

The evolutionary interplay between predator and prey has significantly shaped the development of snake venom, a critical adaptation for subduing prey. This arms race has spurred the diversification of the components of venom and the corresponding emergence of resistance mechanisms in the prey and predators of venomous snakes. Our study investigates the molecular basis of venom resistance in pythons, focusing on electrostatic charge repulsion as a defense against α-neurotoxins binding to the alpha-1 subunit of the postsynaptic nicotinic acetylcholine receptor. Through phylogenetic and bioactivity analyses of orthosteric site sequences from various python species, we explore the prevalence and evolution of amino acid substitutions that confer resistance by electrostatic repulsion, which initially evolved in response to predatory pressure by Naja (cobra) species (which occurs across Africa and Asia). The small African species Python regius retains the two resistance-conferring lysines (positions 189 and 191) of the ancestral Python genus, conferring resistance to sympatric Naja venoms. This differed from the giant African species Python sebae, which has secondarily lost one of these lysines, potentially due to its rapid growth out of the prey size range of sympatric Naja species. In contrast, the two Asian species Python brongersmai (small) and Python bivittatus (giant) share an identical orthosteric site, which exhibits the highest degree of resistance, attributed to three lysine residues in the orthosteric sites. One of these lysines (at orthosteric position 195) evolved in the last common ancestor of these two species, which may reflect an adaptive response to increased predation pressures from the sympatric α-neurotoxic snake-eating genus Ophiophagus (King Cobras) in Asia. All these terrestrial Python species, however, were less neurotoxin-susceptible than pythons in other genera which have evolved under different predatory pressure as: the Asian species Malayopython reticulatus which is arboreal as neonates and juveniles before rapidly reaching sizes as terrestrial adults too large for sympatric Ophiophagus species to consider as prey; and the terrestrial Australian species Aspidites melanocephalus which occupies a niche, devoid of selection pressure from α-neurotoxic predatory snakes. Our findings underline the importance of positive selection in the evolution of venom resistance and suggest a complex evolutionary history involving both conserved traits and secondary evolution. This study enhances our understanding of the molecular adaptations that enable pythons to survive in environments laden with venomous threats and offers insights into the ongoing co-evolution between venomous snakes and their prey. Full article

(This article belongs to the Section Animal Venoms)

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13 pages, 1046 KiB

Open AccessReview

Recent Developments in Engineering Non-Paralytic Botulinum Molecules for Therapeutic Applications

by Aisha Zhantleuova, Charlotte Leese, Anna P. Andreou, Altynay Karimova, Guy Carpenter and Bazbek Davletov

Toxins 2024, 16(4), 175; https://doi.org/10.3390/toxins16040175 - 3 Apr 2024

Cited by 2 | Viewed by 2027

Abstract

This review discusses the expanding application of botulinum neurotoxin in treating neurological conditions. The article specifically explores novel approaches to using non-paralytic botulinum molecules. These new molecules, such as BiTox or el-iBoNT, offer an alternative for patients who face limitations in using paralytic [...] Read more.

This review discusses the expanding application of botulinum neurotoxin in treating neurological conditions. The article specifically explores novel approaches to using non-paralytic botulinum molecules. These new molecules, such as BiTox or el-iBoNT, offer an alternative for patients who face limitations in using paralytic forms of botulinum neurotoxin due to concerns about muscle function loss. We highlight the research findings that confirm not only the effectiveness of these molecules but also their reduced paralytic effect. We also discuss a potential cause for the diminished paralytic action of these molecules, specifically changes in the spatial parameters of the new botulinum molecules. In summary, this article reviews the current research that enhances our understanding of the application of new botulinum neurotoxins in the context of common conditions and suggests new avenues for developing more efficient molecules. Full article

(This article belongs to the Special Issue Clinical Applications and Diversity of Botulinum Toxins)

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16 pages, 7086 KiB

Open AccessArticle

The Gene vepN Regulated by Global Regulatory Factor veA That Affects Aflatoxin Production, Morphological Development and Pathogenicity in Aspergillus flavus

by Jia Xu, Mengqi Jiang, Peng Wang and Qing Kong

Toxins 2024, 16(4), 174; https://doi.org/10.3390/toxins16040174 - 3 Apr 2024

Cited by 1 | Viewed by 1510

Abstract

Velvet (VeA), a light-regulated protein that shuttles between the cytoplasm and the nucleus, serves as a key global regulator of secondary metabolism in various Aspergillus species and plays a pivotal role in controlling multiple developmental processes. The gene vepN was chosen for further [...] Read more.

Velvet (VeA), a light-regulated protein that shuttles between the cytoplasm and the nucleus, serves as a key global regulator of secondary metabolism in various Aspergillus species and plays a pivotal role in controlling multiple developmental processes. The gene vepN was chosen for further investigation through CHIP-seq analysis due to significant alterations in its interaction with VeA under varying conditions. This gene (AFLA_006970) contains a Septin-type guanine nucleotide-binding (G) domain, which has not been previously reported in Aspergillus flavus (A. flavus). The functional role of vepN in A. flavus was elucidated through the creation of a gene knockout mutant and a gene overexpression strain using a well-established dual-crossover recombinational technique. A comparison between the wild type (WT) and the ΔvepN mutant revealed distinct differences in morphology, reproductive capacity, colonization efficiency, and aflatoxin production. The mutant displayed reduced growth rate; dispersion of conidial heads; impaired cell wall integrity; and decreased sclerotia formation, colonization capacity, and aflatoxin levels. Notably, ΔvepN exhibited complete growth inhibition under specific stress conditions, highlighting the essential role of vepN in A. flavus. This study provides evidence that vepN positively influences aflatoxin production, morphological development, and pathogenicity in A. flavus. Full article

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16 pages, 3941 KiB

Open AccessArticle

Meat Starter Culture Reduces Aspergillus parasiticus Production of Aflatoxins on Meat-Based and Salami Model Media

by Iva Zahija Jazbec, Lea Demšar, Barbka Jeršek and Tomaž Polak

Toxins 2024, 16(4), 173; https://doi.org/10.3390/toxins16040173 - 2 Apr 2024

Viewed by 1447

Abstract

There is great concern about the risk posed by the consumption of food contaminated with aflatoxins (AF), produced mostly by Aspergillus strains, that can also be found in dry-fermented meat products (DFMPs). The aim of this study was to investigate the inhibitory effect [...] Read more.

There is great concern about the risk posed by the consumption of food contaminated with aflatoxins (AF), produced mostly by Aspergillus strains, that can also be found in dry-fermented meat products (DFMPs). The aim of this study was to investigate the inhibitory effect of meat starter culture (SC), frequently used for fermentation in the meat industry, on A. parasiticus growth and the production of aflatoxin B1 (AFB1), aflatoxin B2 (AFB2), aflatoxin G1 (AFG1), aflatoxin G2 (AFG2), and sterigmatocystin (STE) on different meat-based (CMA) and salami model (SM-G) media. Incubation was carried out under optimal conditions for fungal growth and under typical conditions for ripening of DFMPs for 21 days. Reversed-phase UPLC–MS/MS analysis was performed to determine mycotoxin production. SC reduced A. parasiticus growth more on CMA than on SM-G media. AFB1 formation was inhibited on both types of SC-containing media, although SC generally had a stronger inhibitory effect on AFB1 production on CMA than on SM-G. AFB1 and AFB2 were produced on CMA, while AFB1 dominated in SM-G, AFG1, and AFG2 were not detected in any media. The results show that SC inhibited AFB1 formation of A. parasiticus on SM-G media after 21 days of incubation under typical conditions for the production of DFMPs. These results indicate the necessity to investigate AF on natural matrices in an environment that is as similar as possible to real conditions in the production of DFMPs. Full article

(This article belongs to the Special Issue Mycotoxins in Food: Detection, Contamination and Management Strategies)

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22 pages, 1227 KiB

Open AccessArticle

The Complex Role of Botulinum Toxin in Enhancing Goal Achievement for Post-Stroke Patients

by Miruna Ioana Săndulescu, Delia Cinteză, Daniela Poenaru, Claudia-Gabriela Potcovaru, Horia Păunescu and Oana Andreia Coman

Toxins 2024, 16(4), 172; https://doi.org/10.3390/toxins16040172 - 31 Mar 2024

Cited by 2 | Viewed by 1786

Abstract

Introduction. The rehabilitation medical team is responsible for the therapeutic management of post-stroke patients and, therefore, for the complex therapeutic approach of spasticity. Considering the generous arsenal at our disposal in terms of both pharmacological treatment, through the possibility of administering botulinum toxin [...] Read more.

Introduction. The rehabilitation medical team is responsible for the therapeutic management of post-stroke patients and, therefore, for the complex therapeutic approach of spasticity. Considering the generous arsenal at our disposal in terms of both pharmacological treatment, through the possibility of administering botulinum toxin to combat spasticity, and in terms of accurate assessment through developed functional scales such as the GAS (Goal Attainment Scale), one of our purposes is to monitor the parameters that influence the achievement of functional goals set by patients together with the medical team in order to render the patients as close as possible to achieving their proposed functional goals, thus enhancing their quality of life. By assessing and establishing statistical and clinical correlations between the GAS and quantifiable parameters related to the affected post-stroke upper limb, namely degree of spasticity, motor control, pain level and evolution of pain under treatment with BoNT-A (abobotulinum toxin A), and patients’ overall response to BoNT-A treatment, we aim to quantify the improvement of the therapeutic management of post-stroke patients with spasticity and develop a more personalized and effective approach to their disability and impairment. Results and discussions. The analysis concluded that there were two independent predictors of the Achieved GAS-T score (the study’s endpoint parameter) motor control at any level of the upper limb and number of prior BoNT-A injections. The number of prior BoNT-A injections was an independent predictor of Achieved GAS-T score improvement but had no significant influence over Baseline GAS-T score. Enhancement in proximal and intermediate motor control showed a GAS score improvement of 3.3 points and a 0.93-point GAS score improvement for wrist motor control progress. From a separate viewpoint, patients with motor deficit on the left side have shown significantly greater improvement in Changed GAS-T scores by 2.5 points compared to patients with deficits on the right side; however, we note as a study limitation the fact that there was no statistical analysis over the dominant cerebral hemisphere of each patient. Conclusions. Improvement in the Achieved GAS-T score means better achievement of patients’ goals. Thus, after the BoNT- A intervention, at follow-up evaluation, GAS was found to be directly correlated with improvement in motor control of the affected upper limb. Mobility of the corresponding limb was enhanced by pain decrease during p-ROM (passive range of motion) and by amelioration of spasticity. Materials and Methods. We conducted an observational, non-randomized clinical study on 52 stroke patients, a representative sample of patients with post-stroke spasticity and disability from our neurological rehabilitation clinic, who have been treated and undergone a specific rehabilitation program in our tertiary diagnostic and treatment medical center, including BoNT-A focal treatment for spasticity in the affected upper limb. The primary objective of the study was to assess the influence of abobotulinum toxin A treatment on the Goal Attainment Scale. Secondary objectives of the study included the assessment of BoNT-A treatment efficacy on spasticity with the MAS (Modified Ashworth Scale), pain with the NRS (Numerical Rating Scale), and joint passive range of motion (p-ROM), identifying demographic, clinical, and pharmacological factors that influence the response to BoNT-A treatment, as well as to conduct a descriptive and exploratory analysis of the studied variables. Full article

(This article belongs to the Special Issue Application of Botulinum Toxins in Diseases Treatment)

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Toxins, Volume 16, Issue 4 (April 2024) – 38 articles

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