Toxins

19 pages, 6269 KiB

Open AccessArticle

The Important Role of Membrane Fluidity on the Lytic Mechanism of the α-Pore-Forming Toxin Sticholysin I

by Lohans Pedrera, Uris Ros, Maria Laura Fanani, María E. Lanio, Richard M. Epand, Ana J. García-Sáez and Carlos Álvarez

Toxins 2023, 15(1), 80; https://doi.org/10.3390/toxins15010080 - 16 Jan 2023

Cited by 1 | Viewed by 2646

Abstract

Actinoporins have emerged as archetypal α-pore-forming toxins (PFTs) that promote the formation of pores in membranes upon oligomerization and insertion of an α-helix pore-forming domain in the bilayer. These proteins have been used as active components of immunotoxins, therefore, understanding their lytic mechanism [...] Read more.

Actinoporins have emerged as archetypal α-pore-forming toxins (PFTs) that promote the formation of pores in membranes upon oligomerization and insertion of an α-helix pore-forming domain in the bilayer. These proteins have been used as active components of immunotoxins, therefore, understanding their lytic mechanism is crucial for developing this and other applications. However, the mechanism of how the biophysical properties of the membrane modulate the properties of pores generated by actinoporins remains unclear. Here we studied the effect of membrane fluidity on the permeabilizing activity of sticholysin I (St I), a toxin that belongs to the actinoporins family of α-PFTs. To modulate membrane fluidity we used vesicles made of an equimolar mixture of phosphatidylcholine (PC) and egg sphingomyelin (eggSM), in which PC contained fatty acids of different acyl chain lengths and degrees of unsaturation. Our detailed single-vesicle analysis revealed that when membrane fluidity is high, most of the vesicles are partially permeabilized in a graded manner. In contrast, more rigid membranes can be either completely permeabilized or not, indicating an all-or-none mechanism. Altogether, our results reveal that St I pores can be heterogeneous in size and stability, and that these properties depend on the fluid state of the lipid bilayer. We propose that membrane fluidity at different regions of cellular membranes is a key factor to modulate the activity of the actinoporins, which has implications for the design of different therapeutic strategies based on their lytic action. Full article

(This article belongs to the Special Issue New Frontiers in Pore-Forming Toxins and Related Proteins: Molecular Mechanisms, Functions and Applications)

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11 pages, 2036 KiB

Open AccessArticle

Ultrasensitive Lateral Flow Immunoassay for Fumonisin B1 Detection Using Highly Luminescent Aggregation-Induced Emission Microbeads

by Ge Xu, Xiaojing Fan, Xirui Chen, Zilong Liu, Guoxin Chen, Xiaxia Wei, Xiangmin Li, Yuankui Leng, Yonghua Xiong and Xiaolin Huang

Toxins 2023, 15(1), 79; https://doi.org/10.3390/toxins15010079 - 16 Jan 2023

Cited by 6 | Viewed by 2643

Abstract

Lateral flow immunoassay (LFIA) based on fluorescent microbeads has attracted much attention for its use in rapid and accurate food safety monitoring. However, conventional fluorescent microbeads are limited by the aggregation-caused quenching effect of the loaded fluorophores, thus resulting in low signal intensity [...] Read more.

Lateral flow immunoassay (LFIA) based on fluorescent microbeads has attracted much attention for its use in rapid and accurate food safety monitoring. However, conventional fluorescent microbeads are limited by the aggregation-caused quenching effect of the loaded fluorophores, thus resulting in low signal intensity and insufficient sensitivity of fluorescent LFIA. In this study, a green-emitting fluorophore with an aggregation-induced emission (AIE) characteristic was encapsulated in polymer nanoparticles via an emulsification technique to form ultrabright fluorescent microbeads (denoted as AIEMBs). The prepared AIEMBs were then applied in a competitive LFIA (AIE-LFIA) as signal reporters for the rapid and highly sensitive screening of fumonisin B1 (FB1) in real corn samples. High sensitivity with a detection limit of 0.024 ng/mL for FB1 was achieved by the developed AIE-LFIA. Excellent selectivity, good accuracy, and high reliability of the AIE-LFIA were demonstrated, indicating a promising platform for FB1 screening. Full article

(This article belongs to the Special Issue Emerging Strategies for Extraction and Analysis of Mycotoxins in Food)

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14 pages, 2222 KiB

Open AccessArticle

Wound Infection of Snakebite from Venomous Protobothrops mucrosquamatus, Viridovipera stejnegeri and Naja atra in Taiwan: Validation of BITE and Cobra BITE Scoring Systems and their Bacteriological Differences in Wound Cultures

by Heng Yeh, Shi-Ying Gao and Chih-Chuan Lin

Toxins 2023, 15(1), 78; https://doi.org/10.3390/toxins15010078 - 15 Jan 2023

Cited by 2 | Viewed by 2127

Abstract

Patients bitten by Protobothrops mucrosquamatus, Viridovipera stejnegeri, and Naja atra develop different degrees of wound infection. This study validated BITE and Cobra BITE scoring systems that we established previously. Bacteriological studies of patients with wound infection were conducted. The operating characteristic [...] Read more.

Patients bitten by Protobothrops mucrosquamatus, Viridovipera stejnegeri, and Naja atra develop different degrees of wound infection. This study validated BITE and Cobra BITE scoring systems that we established previously. Bacteriological studies of patients with wound infection were conducted. The operating characteristic curves and area under the curve (AUC) and wound infection rates were compared between the derivation set (our previous study patient population) and the validation set (new patient cohorts enrolled between June 2017 and May 2021). No significant differences in the AUC for both the BITE (0.84 vs. 0.78, p = 0.27) and Cobra BITE (0.88 vs. 0.75, p = 0.21) scoring systems were observed between the derivation and validation sets. Morganella morganii and Enterococcus faecalis were the two most commonly detected bacteria in the microbiological study. More bacterial species were cultured from N. atra-infected wounds. Antibiotics such as amoxicillin with clavulanic acid, oxacillin, and ampicillin may not be suitable for treating patients with P. mucrosquamatus, V. stejnegeri, and N. atra bites in Taiwan. Carbapenem, third-generation cephalosporins, and fluoroquinolone may be superior alternatives. Full article

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16 pages, 4105 KiB

Open AccessArticle

Volatiles from Pseudomonas palleroniana Strain B-BH16-1 Suppress Aflatoxin Production and Growth of Aspergillus flavus on Coix lacryma-jobi during Storage

by Shihua Zhou, Qing-Song Yuan, Xiaoai Wang, Weike Jiang, Xiaohong Ou, Changgui Yang, Yanping Gao, Yanhong Wang, Lanping Guo, Luqi Huang and Tao Zhou

Toxins 2023, 15(1), 77; https://doi.org/10.3390/toxins15010077 - 14 Jan 2023

Cited by 5 | Viewed by 2420

Abstract

Semen coicis is not only a traditional Chinese medicine (TCM), but also a typical food in China, with significant medical and healthcare value. Because semen coicis is rich in starch and oil, it can be easily contaminated with Aspergillus flavus and its aflatoxins [...] Read more.

Semen coicis is not only a traditional Chinese medicine (TCM), but also a typical food in China, with significant medical and healthcare value. Because semen coicis is rich in starch and oil, it can be easily contaminated with Aspergillus flavus and its aflatoxins (AFs). Preventing and controlling the contamination of semen coicis with Aspergillus flavus and its aflatoxins is vital to ensuring its safety as a drug and as a food. In this study, the endosphere bacteria Pseudomonas palleroniana strain B-BH16-1 produced volatiles that strongly inhibited the mycelial growth and spore formation activity of A. flavus. Gas chromatography–mass spectrometry profiling revealed three volatiles emitted from B-BH16-1, of which 1-undecene was the most abundant. We obtained authentic reference standards for these three volatiles; these significantly reduced mycelial growth and sporulation in Aspergillus, with dimethyl disulfide showing the most robust inhibitory activity. Strain B-BH16-1 was able to completely inhibit the biosynthesis of aflatoxins in semen coicis samples during storage by emitting volatile bioactive components. The microscope revealed severely damaged mycelia and a complete lack of sporulation. This newly identified plant endophyte bacterium was able to strongly inhibit the sporulation and growth of Aspergillus and the synthesis of associated mycotoxins, thus not only providing valuable information regarding an efficient potential strategy for the prevention of A. flavus contamination in TCM and food, but potentially also serving as a reference in the control of toxic fungi. Full article

(This article belongs to the Special Issue Detoxification, Control, and Toxicological Studies on Mycotoxins through Biotechnological Approaches)

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16 pages, 1050 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Effects of Botulinum Toxin Type A on the Nociceptive and Lemniscal Somatosensory Systems in Chronic Migraine: An Electrophysiological Study

by Gabriele Sebastianelli, Francesco Casillo, Antonio Di Renzo, Chiara Abagnale, Ettore Cioffi, Vincenzo Parisi, Cherubino Di Lorenzo, Mariano Serrao, Francesco Pierelli, Jean Schoenen and Gianluca Coppola

Toxins 2023, 15(1), 76; https://doi.org/10.3390/toxins15010076 - 14 Jan 2023

Cited by 7 | Viewed by 3936

Abstract

(1) Background: OnabotulinumtoxinA (BoNT-A) is a commonly used prophylactic treatment for chronic migraine (CM). Although randomized placebo studies have shown its clinical efficacy, the mechanisms by which it exerts its therapeutic effect are still incompletely understood and debated. (2) Methods: We studied in [...] Read more.

(1) Background: OnabotulinumtoxinA (BoNT-A) is a commonly used prophylactic treatment for chronic migraine (CM). Although randomized placebo studies have shown its clinical efficacy, the mechanisms by which it exerts its therapeutic effect are still incompletely understood and debated. (2) Methods: We studied in 15 CM patients the cephalic and extracephalic nociceptive and lemniscal sensory systems using electrophysiological techniques before and 1 and 3 months after one session of pericranial BoNT-A injections according to the PREEMPT protocol. We recorded the nociceptive blink reflex (nBR), the trigemino-cervical reflex (nTCR), the pain-related cortical evoked potential (PREP), and the upper limb somatosensory evoked potential (SSEP). (3) Results: Three months after a single session of prophylactic therapy with BoNT-A in CM patients, we found (a) an increase in the homolateral and contralateral nBR AUC, (b) an enhancement of the contralateral nBR AUC habituation slope and the nTCR habituation slope, (c) a decrease in PREP N-P 1st and 2nd amplitude block, and (d) no effect on SSEPs. (4) Conclusions: Our study provides electrophysiological evidence for the ability of a single session of BoNT-A injections to exert a neuromodulatory effect at the level of trigeminal system through a reduction in input from meningeal and other trigeminovascular nociceptors. Moreover, by reducing activity in cortical pain processing areas, BoNT-A restores normal functioning of the descending pain modulation systems. Full article

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

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19 pages, 4212 KiB

Open AccessArticle

Changes in Spirulina’s Physical and Chemical Properties during Submerged and Solid-State Lacto-Fermentation

by Ernesta Tolpeznikaite, Vadims Bartkevics, Anna Skrastina, Romans Pavlenko, Ernestas Mockus, Egle Zokaityte, Vytaute Starkute, Dovile Klupsaite, Romas Ruibys, João Miguel Rocha, Antonello Santini and Elena Bartkiene

Toxins 2023, 15(1), 75; https://doi.org/10.3390/toxins15010075 - 13 Jan 2023

Cited by 4 | Viewed by 2287

Abstract

The aim of this study was to select a lactic acid bacteria (LAB) strain for bio-conversion of Spirulina, a cyanobacteria (“blue-green algae”), into an ingredient with a high concentration of gamma-aminobutyric acid (GABA) for human and animal nutrition. For this purpose, ten different [...] Read more.

The aim of this study was to select a lactic acid bacteria (LAB) strain for bio-conversion of Spirulina, a cyanobacteria (“blue-green algae”), into an ingredient with a high concentration of gamma-aminobutyric acid (GABA) for human and animal nutrition. For this purpose, ten different LAB strains and two different fermentation conditions (SMF (submerged) and SSF (solid state fermentation)) were tested. In addition, the concentrations of fatty acids (FA) and biogenic amines (BA) in Spirulina samples were evaluated. It was established that Spirulina is a suitable substrate for fermentation, and the lowest pH value (4.10) was obtained in the 48 h SSF with Levilactobacillus brevis. The main FA in Spirulina were methyl palmitate, methyl linoleate and gamma-linolenic acid methyl ester. Fermentation conditions were a key factor toward glutamic acid concentration in Spirulina, and the highest concentration of GABA (2395.9 mg/kg) was found in 48 h SSF with Lacticaseibacillus paracasei samples. However, a significant correlation was found between BA and GABA concentrations, and the main BA in fermented Spirulina samples were putrescine and spermidine. Finally, the samples in which the highest GABA concentrations were found also displayed the highest content of BA. For this reason, not only the concentration of functional compounds in the end-product must be controlled, but also non-desirable substances, because both of these compounds are produced through similar metabolic pathways of the decarboxylation of amino acids. Full article

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18 pages, 6580 KiB

Open AccessEditor’s ChoiceArticle

Highly Evolvable: Investigating Interspecific and Intraspecific Venom Variation in Taipans (Oxyuranus spp.) and Brown Snakes (Pseudonaja spp.)

by Jory van Thiel, Luis L. Alonso, Julien Slagboom, Nathan Dunstan, Roel M. Wouters, Cassandra M. Modahl, Freek J. Vonk, Timothy N. W. Jackson and Jeroen Kool

Toxins 2023, 15(1), 74; https://doi.org/10.3390/toxins15010074 - 13 Jan 2023

Cited by 11 | Viewed by 3599

Abstract

Snake venoms are complex mixtures of toxins that differ on interspecific (between species) and intraspecific (within species) levels. Whether venom variation within a group of closely related species is explained by the presence, absence and/or relative abundances of venom toxins remains largely unknown. [...] Read more.

Snake venoms are complex mixtures of toxins that differ on interspecific (between species) and intraspecific (within species) levels. Whether venom variation within a group of closely related species is explained by the presence, absence and/or relative abundances of venom toxins remains largely unknown. Taipans (Oxyuranus spp.) and brown snakes (Pseudonaja spp.) represent medically relevant species of snakes across the Australasian region and provide an excellent model clade for studying interspecific and intraspecific venom variation. Using liquid chromatography with ultraviolet and mass spectrometry detection, we analyzed a total of 31 venoms covering all species of this monophyletic clade, including widespread localities. Our results reveal major interspecific and intraspecific venom variation in Oxyuranus and Pseudonaja species, partially corresponding with their geographical regions and phylogenetic relationships. This extensive venom variability is generated by a combination of the absence/presence and differential abundance of venom toxins. Our study highlights that venom systems can be highly dynamical on the interspecific and intraspecific levels and underscores that the rapid toxin evolvability potentially causes major impacts on neglected tropical snakebites. Full article

(This article belongs to the Section Animal Venoms)

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22 pages, 11807 KiB

Open AccessArticle

The Mechanism of Houttuynia cordata Embryotoxicity Was Explored in Combination with an Experimental Model and Network Pharmacology

by Yufu Liu, Guodong Yang, Chunqi Yang, Zhuo Shi, Yi Ru, Ningning Shen, Chengrong Xiao, Yuguang Wang and Yue Gao

Toxins 2023, 15(1), 73; https://doi.org/10.3390/toxins15010073 - 13 Jan 2023

Cited by 6 | Viewed by 3230

Abstract

Houttuynia cordata (H. cordata) is the most common herb as a food and traditional Chinese medicine. Currently, studies on its toxicity have mainly focused on hepatotoxicity. However, its potential embryotoxicity by long-term exposure is often overlooked. Objective: To investigate the effects [...] Read more.

Houttuynia cordata (H. cordata) is the most common herb as a food and traditional Chinese medicine. Currently, studies on its toxicity have mainly focused on hepatotoxicity. However, its potential embryotoxicity by long-term exposure is often overlooked. Objective: To investigate the effects of H. cordata on embryonic development and its toxicity mechanism by combining network pharmacology, molecular docking, and in vitro experimental methods. Methods: The effects of H. cordata on embryos were evaluated. Zebrafish embryos and embryoid bodies were administered to observe the effects of H. cordata on embryonic development. Based on network pharmacological analysis, it was found that the main active agents producing toxicity in H. cordata were oleanolic acid, lignan, and aristolactam AII. H. cordata can affect PI3K-Akt, MAPK, and Ras signaling pathways by regulating targets, such as AKT1, EGFR, CASP3, and IGF-1. RT-PCR and immunohistochemistry results showed that the expression of AKT1 and PI3K in the embryoid body was significantly reduced after drug administration (p < 0.05). Conclusions: The results of network pharmacology and in vitro experiments suggest that H. cordata may affect embryonic development by influencing the PI3K-Akt signaling pathway. Full article

(This article belongs to the Special Issue Toxicity of Plant Toxins in Medicinal Herbs: What’s New?)

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17 pages, 2837 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Montane Rattlesnakes in México: Venoms of Crotalus tancitarensis and Related Species within the Crotalus intermedius Group

by Emily R. Grabowsky, Anthony J. Saviola, Javier Alvarado-Díaz, Adrian Quijada Mascareñas, Kirk C. Hansen, John R. Yates III and Stephen P. Mackessy

Toxins 2023, 15(1), 72; https://doi.org/10.3390/toxins15010072 - 13 Jan 2023

Cited by 2 | Viewed by 2940

Abstract

The Crotalus intermedius group is a clade of rattlesnakes consisting of several species adapted to a high elevation habitat, primarily in México. Crotalus tancitarensis was previously classified as C. intermedius, until individuals occurring on Cerro Tancítaro in Michoacán, México, were reevaluated and [...] Read more.

The Crotalus intermedius group is a clade of rattlesnakes consisting of several species adapted to a high elevation habitat, primarily in México. Crotalus tancitarensis was previously classified as C. intermedius, until individuals occurring on Cerro Tancítaro in Michoacán, México, were reevaluated and classified as a new species (C. tancitarensis) based on scale pattern and geographic location. This study aimed to characterize the venom of C. tancitarensis and compare the venom profile to those of other species within the Crotalus intermedius group using gel electrophoresis, biochemical assays, reverse-phase high performance liquid chromatography, mass spectrometry, and lethal toxicity (LD₅₀) assays. Results show that the venom profiles of species within the Crotalus intermedius group are similar, but with distinct differences in phospholipase A₂ (PLA₂), metalloproteinase PI (SVMP PI), and kallikrein-like serine proteinase (SVSP) activity and relative abundance. Proteomic analysis indicated that the highland forms produce venoms with 50–60 protein isoforms and a composition typical of type I rattlesnake venoms (abundant SVMPs, lack of presynaptic PLA₂-based neurotoxins), as well as a diversity of typical Crotalus venom components such as serine proteinases, PLA₂s, C-type lectins, and less abundant toxins (LAAOs, CRiSPs, etc.). The overall venom profile of C. tancitarensis appears most similar to C. transversus, which is consistent with a previous mitochondrial DNA analysis of the Crotalus intermedius group. These rattlesnakes of the Mexican highlands represent a radiation of high elevation specialists, and in spite of divergence of species in these Sky Island habitats, venom composition of species analyzed here has remained relatively conserved. The majority of protein family isoforms are conserved in all members of the clade, and as seen in other more broadly distributed rattlesnake species, differences in their venoms are largely due to relative concentrations of specific components. Full article

(This article belongs to the Section Animal Venoms)

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17 pages, 8372 KiB

Open AccessArticle

Brazilian Table Olives: A Source of Lactic Acid Bacteria with Antimycotoxigenic and Antifungal Activity

by Luara Simões, Natália Fernandes, José Teixeira, Luís Abrunhosa and Disney Ribeiro Dias

Toxins 2023, 15(1), 71; https://doi.org/10.3390/toxins15010071 - 13 Jan 2023

Cited by 8 | Viewed by 2835

Abstract

Food and feed contamination by fungi, especially by toxigenic ones, is a global concern because it can pose serious health problems when the production of mycotoxins is involved. Lactic acid bacteria (LAB), well-known for fermenting foods, have been gaining attention for their antifungal [...] Read more.

Food and feed contamination by fungi, especially by toxigenic ones, is a global concern because it can pose serious health problems when the production of mycotoxins is involved. Lactic acid bacteria (LAB), well-known for fermenting foods, have been gaining attention for their antifungal and anti-mycotoxin properties. This work tested 14 LAB strains isolated from naturally fermented Brazilian table olives for growth inhibition of Aspergillus flavus, Aspergillus carbonarius, Penicillium nordicum, and Penicillium expansum. The strains Lacticaseibacillus paracasei subsp. paracasei CCMA 1764, Levilactobacillus brevis CCMA 1762, and Lactiplantibacillus pentosus CCMA 1768 showed the strongest antifungal activity, being more active against P. expansum. Aflatoxin B1 (AFB1), ochratoxin A (OTA), and patulin (PAT) production was reduced essentially by mycelia growth inhibition. The main organic acids detected in the cell free supernatant (CFS) were lactic and acetic acids. Tested LAB exhibited adsorption capacity against AFB1 (48–51%), OTA (28–33%), and PAT (23–24%). AFB1 was converted into aflatoxin B2a (AFB2a) by lactic and acetic acids produced by the strain CCMA 1764. A similar conversion was observed in solutions of these organic acids (0.1 M). These findings demonstrate the potential of isolated LAB strains as natural agents to control toxigenic fungi and their mycotoxins in fermented products, such as table olives. Full article

(This article belongs to the Section Mycotoxins)

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10 pages, 2487 KiB

Open AccessArticle

The Bi-Functional Paxilline Enriched in Skin Secretion of Tree Frogs (Hyla japonica) Targets the KCNK18 and BK_Ca Channels

by Chuanling Yin, Fanpeng Zeng, Puyi Huang, Zhengqi Shi, Qianyi Yang, Zhenduo Pei, Xin Wang, Longhui Chai, Shipei Zhang, Shilong Yang, Wenqi Dong, Xiancui Lu and Yunfei Wang

Toxins 2023, 15(1), 70; https://doi.org/10.3390/toxins15010070 - 12 Jan 2023

Cited by 1 | Viewed by 2276

Abstract

The skin secretion of tree frogs contains a vast array of bioactive chemicals for repelling predators, but their structural and functional diversity is not fully understood. Paxilline (PAX), a compound synthesized by Penicillium paxilli, has been known as a specific antagonist of large [...] Read more.

The skin secretion of tree frogs contains a vast array of bioactive chemicals for repelling predators, but their structural and functional diversity is not fully understood. Paxilline (PAX), a compound synthesized by Penicillium paxilli, has been known as a specific antagonist of large conductance Ca²⁺-activated K⁺ Channels (BK_Ca). Here, we report the presence of PAX in the secretions of tree frogs (Hyla japonica) and that this compound has a novel function of inhibiting the potassium channel subfamily K member 18 (KCNK18) channels of their predators. The PAX-induced KCNK18 inhibition is sufficient to evoke Ca²⁺ influx in charybdotoxin-insensitive DRG neurons of rats. By forming π-π stacking interactions, four phenylalanines located in the central pore of KCNK18 stabilize PAX to block the ion permeation. For PAX-mediated toxicity, our results from animal assays suggest that the inhibition of KCNK18 likely acts synergistically with that of BK_Ca to elicit tingling and buzzing sensations in predators or competitors. These results not only show the molecular mechanism of PAX-KCNK18 interaction, but also provide insights into the defensive effects of the enriched PAX. Full article

(This article belongs to the Special Issue Advanced Research on Animal Venoms in China)

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12 pages, 1538 KiB

Open AccessArticle

Origanum vulgare Essential Oil Modulates the AFB1-Induced Oxidative Damages, Nephropathy, and Altered Inflammatory Responses in Growing Rabbits

by Mona A. Hassan, Azza M. A. Abo-Elmaaty, Asmaa W. Zaglool, Sally A. M. Mohamed, Shimaa M. Abou-Zeid, Mayada R. Farag, Mahmoud Alagawany, Alessandro Di Cerbo, Mahmoud M. Azzam, Rashed Alhotan and Enas EL-Hady

Toxins 2023, 15(1), 69; https://doi.org/10.3390/toxins15010069 - 12 Jan 2023

Cited by 10 | Viewed by 2387

Abstract

The current study was performed to investigate the toxic effects of aflatoxin B1 (AFB1) through the evaluation of kidney function tests and histopathological examination of renal tissues, targeting the therapeutic role of Marjoram (Origanum vulgare essential oil-OEO) in improving health status. Forty-eight [...] Read more.

The current study was performed to investigate the toxic effects of aflatoxin B1 (AFB1) through the evaluation of kidney function tests and histopathological examination of renal tissues, targeting the therapeutic role of Marjoram (Origanum vulgare essential oil-OEO) in improving health status. Forty-eight New Zealand Whites growing rabbits (four weeks old) weighing on average 660.5 ± 2.33 g were randomly and equally distributed into four groups, each of which had four replicas of three animals as the following: Control group (only basal diet), AFB1 group (0.3 mg AFB1/kg diet), OEO group (1 g OEO/kg diet) and co-exposed group (1 g OEO/kg + 0.3 mg AF/kg diet). Our study lasted eight weeks and was completed at 12 weeks of age. The results revealed that OEO decreased the toxic effects of AFB1 in rabbit kidneys by substantially reducing the cystatin C levels in the AFB1 group. Additionally, OEO decreased oxidative stress and lipid peroxidation levels in the co-exposed group. Moreover, OEO reduced DNA damage and inflammatory response in addition to the down-regulation of stress and inflammatory cytokines-encoding genes. Besides, OEO preserved the cytoarchitecture of rabbits’ kidneys treated with AFB1. In conclusion, O. vulgare essential oil supplementation ameliorated the deleterious effects of AFB1 on the rabbits’ kidneys by raising antioxidant levels, decreasing inflammation, and reversing oxidative DNA damage. Full article

(This article belongs to the Special Issue Mycotoxins and Fungal Toxins: Current Status and Future Perspectives)

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14 pages, 29465 KiB

Open AccessEditor’s ChoiceArticle

Solanum nigrum Fruit Extract Modulates Immune System Activity of Mealworm Beetle, Tenebrio molitor L.

by Arkadiusz Urbański, Natalia Konopińska, Natalia Bylewska, Radosław Gmyrek, Marta Spochacz-Santoro, Sabino Aurelio Bufo and Zbigniew Adamski

Toxins 2023, 15(1), 68; https://doi.org/10.3390/toxins15010068 - 12 Jan 2023

Cited by 3 | Viewed by 2581

Abstract

Here, we report the first evidence concerning the modulation of insect immune system activity after applying Solanum nigrum fruit extract (EXT). We focused on two main issues: (1) is EXT cytotoxic for Tenebrio molitor haemocytes? and (2) how EXT affects the basic immune [...] Read more.

Here, we report the first evidence concerning the modulation of insect immune system activity after applying Solanum nigrum fruit extract (EXT). We focused on two main issues: (1) is EXT cytotoxic for Tenebrio molitor haemocytes? and (2) how EXT affects the basic immune mechanisms of T. molitor. The results indicate cytotoxic action of 0.01 and 0.1% EXT on beetle haemocytes. Both the injection of EXT and incubating haemocytes with the EXT solution on microscopic slides significantly increased the number of apoptotic cells. However, 24 h after injection of 0.1% EXT cytotoxic effect of the tested extract probably was masked by the increased number of circulating haemocytes. Application of 0.01 and 0.1% EXT led to impairment of the activity of basic immune mechanisms such as phenoloxidase activity and the lysozyme-like antimicrobial activity of T. molitor haemolymph. Moreover, the EXT elicited significant changes in the expression level of selected immune genes. However, some of the immunomodulatory effects of EXT were different in beetles with and without an activated immune system. The obtained results are an essential step toward a complete understanding of the EXT mode of action on the T. molitor physiology and its potential usage in pest control. Full article

(This article belongs to the Special Issue Toxic Secondary Plant Metabolites: Toxicology, Medicine, Pharmacology, Ecotoxicology and Crop Protection)

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15 pages, 10109 KiB

Open AccessArticle

Alveolar Macrophages Participate in the Promotion of Influenza Virus Infection by Aflatoxin B1 at an Early Stage

by Yuhang Sun, Zhaoran Yao, Miao Long, Ying Zhang, Kehe Huang and Lin Li

Toxins 2023, 15(1), 67; https://doi.org/10.3390/toxins15010067 - 12 Jan 2023

Cited by 3 | Viewed by 2099

Abstract

Aflatoxin B1 (AFB1), one of the most common environmental mycotoxin contaminations in food and feed, poses significant threats to human and animal health. Our previous study indicated that even non-toxic AFB1 concentrations could promote influenza virus replication and induce influenza virus-infected alveolar macrophages [...] Read more.

Aflatoxin B1 (AFB1), one of the most common environmental mycotoxin contaminations in food and feed, poses significant threats to human and animal health. Our previous study indicated that even non-toxic AFB1 concentrations could promote influenza virus replication and induce influenza virus-infected alveolar macrophages polarizing from M1 (immunostimulatory phenotype) to M2 (immunosuppressive phenotype) over time. However, whether AFB1 promotes influenza replication via modulating the polarization of alveolar macrophages is unknown. Here, we specifically depleted alveolar macrophages using clodronate-containing liposomes in swine influenza virus (SIV)-infected mice to explore the mechanism the promotion of SIV replication by AFB1. The results show that the depletion of alveolar macrophages significantly alleviated the AFB1-induced weight loss, inflammatory responses, and lung and immune organ damage of the SIV-infected mice after 14 days and greatly diminished the AFB1-promoted SIV replication. In contrast, the depletion of alveolar macrophages did not alleviate the AFB1-induced weight loss, and lung and immune organ damage of the SIV-infected mice after 28 days and slightly diminished the AFB1-promoted SIV replication. Collectively, the data indicate that alveolar macrophages play a crucial role the promotion of SIV infection by AFB1 in the early rather than late stage, and AFB1 can promote SIV replication by inducing alveolar macrophages to polarize towards M1 macrophages. This research provides novel targets for reducing the risk of AFB1-promoted influenza virus infection. Full article

(This article belongs to the Section Mycotoxins)

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11 pages, 1842 KiB

Open AccessArticle

Inhibition of Tolaasin Cytotoxicity Causing Brown Blotch Disease in Cultivated Mushrooms Using Tolaasin Inhibitory Factors

by Yeong-Bae Yun, Kwang-Hyun Cho and Young-Kee Kim

Toxins 2023, 15(1), 66; https://doi.org/10.3390/toxins15010066 - 12 Jan 2023

Cited by 5 | Viewed by 1977

Abstract

Tolaasin, a pore-forming bacterial peptide toxin secreted by Pseudomonas tolaasii, causes brown blotch disease in cultivated mushrooms by forming membrane pores and collapsing the membrane structures. Tolaasin is a lipodepsipeptide, MW 1985, and pore formation by tolaasin molecules is accomplished by hydrophobic [...] Read more.

Tolaasin, a pore-forming bacterial peptide toxin secreted by Pseudomonas tolaasii, causes brown blotch disease in cultivated mushrooms by forming membrane pores and collapsing the membrane structures. Tolaasin is a lipodepsipeptide, MW 1985, and pore formation by tolaasin molecules is accomplished by hydrophobic interactions and multimerizations. Compounds that inhibit tolaasin toxicity have been isolated from various food additives. Food detergents, sucrose esters of fatty acids, and polyglycerol esters of fatty acids can effectively inhibit tolaasin cytotoxicity. These chemicals, named tolaasin-inhibitory factors (TIF), were effective at concentrations ranging from 10⁻⁴ to 10⁻⁵ M. The most effective compound, TIF 16, inhibited tolaasin-induced hemolysis independent of temperature and pH, while tolaasin toxicity increased at higher temperatures. When TIF 16 was added to tolaasin-pretreated erythrocytes, the cytotoxic activity of tolaasin immediately stopped, and no further hemolysis was observed. In the artificial lipid bilayer, the single-channel activity of the tolaasin channel was completely and irreversibly blocked by TIF 16. When TIF 16 was sprayed onto pathogen-treated oyster mushrooms growing on the shelves of cultivation houses, the development of disease was completely suppressed, and normal growth of oyster mushrooms was observed. Furthermore, the treatment with TIF 16 did not show any adverse effect on the growth of oyster mushrooms. These results indicate that TIF 16 is a good candidate for the biochemical control of brown blotch disease. Full article

(This article belongs to the Section Bacterial Toxins)

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14 pages, 2106 KiB

Open AccessArticle

Biodegradation of Aflatoxin B₁ in the Baijiu Brewing Process by Bacillus cereus

by Guoli Xue, Yanjun Qu, Dan Wu, Shuyuan Huang, Yuqing Che, Jing Yu and Ping Song

Toxins 2023, 15(1), 65; https://doi.org/10.3390/toxins15010065 - 12 Jan 2023

Cited by 9 | Viewed by 2784

Abstract

Aflatoxin is a potent mycotoxin and a common source of grain contamination that leads to great economic losses and health problems. Although distilled baijiu cannot be contaminated by aflatoxin, its presence in the brewing process affects the physiological activities of micro-organisms and reduces [...] Read more.

Aflatoxin is a potent mycotoxin and a common source of grain contamination that leads to great economic losses and health problems. Although distilled baijiu cannot be contaminated by aflatoxin, its presence in the brewing process affects the physiological activities of micro-organisms and reduces product quality. Bacillus cereus XSWW9 capable of degrading aflatoxin B₁ (AFB₁) was isolated from daqu using coumarin as the sole carbon source. XSWW9 degraded 86.7% of 1 mg/L AFB₁ after incubation at 37 °C for 72 h and tolerated up to 1 mg/L AFB₁ with no inhibitory effects. Enzymes in the cell-free supernatant of XSSW9 played a significant role in AFB₁ degradation. The AFB₁-degradation activity was sensitive to protease K and SDS treatment, which indicated that extracellular proteins were responsible for the degradation of AFB₁. In order to investigate the AFB₁-degradation ability of XSSW9 during the baijiu brewing process, AFB₁ and XSWW9 were added to grain fermentation (FG-T) and normal grain fermentation without AFB₁, while normal grain fermentation without AFB₁ and XSWW9 was used as a control (FG-C). At the end of the fermentation, 99% AFB₁ was degraded in the residue of fermented grains. The differences of microbial communities in the fermented grains showed that there were no significant differences between FG-T and FG-C in the relative abundance of dominant genera. The analysis of volatile compounds of their distillation showed that the contents of skeleton flavor components was similar between FG-T and FG-C. These results offer a basis for the development of effective strategies to reduce the effect of AFB₁ on the brewing process and ensure that the production of baijiu is stable. Full article

(This article belongs to the Special Issue Strategies to Prevent Mycotoxin Contamination of Food and Feed)

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1 pages, 194 KiB

Open AccessCorrection

Correction: Kim et al. The Medium Cut-Off Membrane Does Not Lower Protein-Bound Uremic Toxins. Toxins 2022, 14, 779

by Yang Gyun Kim, Sang Ho Lee, Su Woong Jung, Gun Tae Jung, Hyun Ji Lim, Kwang Pyo Kim, Young-Il Jo, KyuBok Jin and Ju Young Moon

Toxins 2023, 15(1), 64; https://doi.org/10.3390/toxins15010064 - 11 Jan 2023

Viewed by 1184

Abstract

In the original publication [...] Full article

(This article belongs to the Special Issue Uremic Toxins Lowering Strategies in Chronic Kidney Disease)

20 pages, 2982 KiB

Open AccessArticle

Mycotoxin Occurrence in Feeds and Raw Materials in China: A Five-Year Investigation

by Wei Hao, Shu Guan, Anping Li, Jinyong Wang, Gang An, Ursula Hofstetter and Gerd Schatzmayr

Toxins 2023, 15(1), 63; https://doi.org/10.3390/toxins15010063 - 11 Jan 2023

Cited by 17 | Viewed by 3203

Abstract

Mycotoxins are ubiquitously present in feeds and raw materials and can exert toxicity on animals and humans. Therefore, mycotoxin occurrence should be monitored. We report here a multi-mycotoxin survey of feed samples in China from 2017 to 2021. Concentrations of aflatoxins, trichothecenes type [...] Read more.

Mycotoxins are ubiquitously present in feeds and raw materials and can exert toxicity on animals and humans. Therefore, mycotoxin occurrence should be monitored. We report here a multi-mycotoxin survey of feed samples in China from 2017 to 2021. Concentrations of aflatoxins, trichothecenes type B, fumonisins, and zearalenone were determined in a total of 9392 samples collected throughout China. Regional differences and year-to-year variation of mycotoxin occurrence were also assessed in new-season corn. Generally, Fusarium mycotoxins were prevalent, while mycotoxin contamination in each feed commodity showed a distinct pattern, e.g., wheat and bran were typically affected by trichothecenes type B, peanut meals were highly susceptible to aflatoxins, and finished feeds exhibited a comparatively high prevalence of all mycotoxins. In new-season corn, trichothecenes type B and fumonisins were most prevalent, with positive rates of 84.04% and 87.16%, respectively. Regions exhibited different patterns of mycotoxin occurrence. The Anhui and Jiangsu provinces of East China exhibited a high prevalence and concentrations of aflatoxins with a positive rate and a positive average of 82.61% and 103.08 μg/kg, respectively. Central China obtained high fumonisins levels of 4707.84 μg/kg. Trichothecenes type B and zearalenone occurred more frequently in temperate regions of Northeast China, and their positive rates reached 94.99% and 55.67%, respectively. In these regions, mycotoxin concentrations in new-season corn exhibited pronounced year-to-year variations and this could be due to the unusual changes of rainfall or temperature during sensitive periods of corn growing. A large fraction of new-season corn samples contained multiple mycotoxins with two to three classes (75.42%), and the most frequently observed co-contaminants were the combination of trichothecenes type B and fumonisins (73.52%). Trichothecenes type B and zearalenone concentrations were highly positively correlated with a coefficient of 0.775. In conclusion, mycotoxins contamination and co-contamination of feeds are common. Mycotoxin contamination in new-season corn exhibited regional patterns and year-to-year variations, with climate and weather conditions as determinant factors. Full article

(This article belongs to the Special Issue Looking Forward: Mycotoxins Occurrence and Detection in Food and Feed)

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15 pages, 1634 KiB

Open AccessEditor’s ChoiceArticle

In Vitro Efficacy of Antivenom and Varespladib in Neutralising Chinese Russell’s Viper (Daboia siamensis) Venom Toxicity

by Mimi Lay, Qing Liang, Geoffrey K. Isbister and Wayne C. Hodgson

Toxins 2023, 15(1), 62; https://doi.org/10.3390/toxins15010062 - 11 Jan 2023

Cited by 11 | Viewed by 2728

Abstract

The venom of the Russell’s viper (Daboia siamensis) contains neurotoxic and myotoxic phospholipase A₂ toxins which can cause irreversible damage to motor nerve terminals. Due to the time delay between envenoming and antivenom administration, antivenoms may have limited efficacy against [...] Read more.

The venom of the Russell’s viper (Daboia siamensis) contains neurotoxic and myotoxic phospholipase A₂ toxins which can cause irreversible damage to motor nerve terminals. Due to the time delay between envenoming and antivenom administration, antivenoms may have limited efficacy against some of these venom components. Hence, there is a need for adjunct treatments to circumvent these limitations. In this study, we examined the efficacy of Chinese D. siamensis antivenom alone, and in combination with a PLA₂ inhibitor, Varespladib, in reversing the in vitro neuromuscular blockade in the chick biventer cervicis nerve-muscle preparation. Pre-synaptic neurotoxicity and myotoxicity were not reversed by the addition of Chinese D. siamensis antivenom 30 or 60 min after venom (10 µg/mL). The prior addition of Varespladib prevented the neurotoxic and myotoxic activity of venom (10 µg/mL) and was also able to prevent further reductions in neuromuscular block and muscle twitches when added 60 min after venom. The addition of the combination of Varespladib and antivenom 60 min after venom failed to produce further improvements than Varespladib alone. This demonstrates that the window of time in which antivenom remains effective is relatively short compared to Varespladib and small-molecule inhibitors may be effective in abrogating some activities of Chinese D. siamensis venom. Full article

(This article belongs to the Special Issue Advanced Research on Animal Venoms in China)

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16 pages, 1613 KiB

Open AccessEditor’s ChoiceArticle

Sustainable Strategies to Counteract Mycotoxins Contamination and Cowpea Weevil in Chickpea Seeds during Post-Harvest

by Claudia Pisuttu, Samuele Risoli, Lorenzo Moncini, Cristina Nali, Elisa Pellegrini and Sabrina Sarrocco

Toxins 2023, 15(1), 61; https://doi.org/10.3390/toxins15010061 - 11 Jan 2023

Cited by 13 | Viewed by 3609

Abstract

Mycotoxins contamination and pest infestation of foods and feeds represent a pivotal threat for food safety and security worldwide, with crucial implications for human and animal health. Controlled atmosphere could be a sustainable strategy to reduce mycotoxins content and counteract the vitality of [...] Read more.

Mycotoxins contamination and pest infestation of foods and feeds represent a pivotal threat for food safety and security worldwide, with crucial implications for human and animal health. Controlled atmosphere could be a sustainable strategy to reduce mycotoxins content and counteract the vitality of deleterious organisms in foodstuff. Ozone treatment (O₃, 500 ppb for 30, 60 or 90 min) and high nitrogen concentration (N₂, 99% for 21 consecutive days) were tested in the post-harvest management of four batches of Cicer arietinum grains to control the presence of mycotoxigenic fungi and their secondary metabolites, as well as pest (i.e., Callosobruchus maculatus) infestation. At the end of the treatment, O₃ significantly decreased the incidence of Penicillium spp. (by an average of −50%, independently to the time of exposure) and reduced the patulin and aflatoxins content after 30 min (−85 and −100%, respectively). High N₂ concentrations remarkably reduced mycotoxins contamination (by an average of −94%) and induced pest mortality (at 100% after 5 days of exposure). These results confirm the promising potential of O₃ and N₂ in post-harvest conservation strategies, leading to further investigations to evaluate the effects on the qualitative characteristics of grains. Full article

(This article belongs to the Special Issue Novel Strategies for Biodegradation and Detoxification of Mycotoxins)

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13 pages, 2278 KiB

Open AccessArticle

Clinical Immunogenicity of DaxibotulinumtoxinA for Injection in Glabellar Lines: Pooled Data from the SAKURA Phase 3 Trials

by Conor J. Gallagher, Ronald R. Bowsher, Amanda Clancy, Jeffrey S. Dover, Shannon Humphrey, Yan Liu and Gregg Prawdzik

Toxins 2023, 15(1), 60; https://doi.org/10.3390/toxins15010060 - 10 Jan 2023

Cited by 10 | Viewed by 3508

Abstract

DaxibotulinumtoxinA for Injection (DAXI) is a novel botulinum toxin type A product containing daxibotulinumtoxinA with a stabilizing excipient peptide (RTP004). DAXI immunogenicity was assessed in three phase 3 glabellar line studies (two placebo-controlled, single-dose studies and an open-label repeat-dose safety study). Binding antibodies [...] Read more.

DaxibotulinumtoxinA for Injection (DAXI) is a novel botulinum toxin type A product containing daxibotulinumtoxinA with a stabilizing excipient peptide (RTP004). DAXI immunogenicity was assessed in three phase 3 glabellar line studies (two placebo-controlled, single-dose studies and an open-label repeat-dose safety study). Binding antibodies to daxibotulinumtoxinA and RTP004 were detected by validated ELISAs. Samples positive for daxibotulinumtoxinA-binding antibodies were evaluated further for titer and neutralizing antibodies by mouse protection assay. Overall, 2786 subjects received DAXI and 2823 subjects were exposed to RTP004 as DAXI (n = 2786) or placebo (n = 37). Treatment-related anti-daxibotulinumtoxinA binding antibodies were detected in 21 of 2737 evaluable subjects (0.8%). No subject developed neutralizing antibodies. Treatment-related anti-RTP004 binding antibodies were detected in 35 (1.3%) of 2772 evaluable subjects. Binding antibodies were generally transient, of low titer (<1:200), and no subject had binding antibodies to both daxibotulinumtoxinA and RTP004. All subjects with treatment-induced binding antibodies to daxibotulinumtoxinA or RTP004 achieved none or mild glabellar line severity at Week 4 following each DAXI cycle, indicating no impact on DAXI efficacy. No subjects with binding antibodies to daxibotulinumtoxinA or RTP004 reported immune-related adverse events. This evaluation of anti-drug antibody formation with DAXI shows low rates of antibody formation to both daxibotulinumtoxinA and RTP004. Full article

(This article belongs to the Section Bacterial Toxins)

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28 pages, 697 KiB

Open AccessReview

OnabotulinumtoxinA: Still the Present for Chronic Migraine

by Carlo Baraldi, Flavia Lo Castro, Raffaele Ornello, Simona Sacco, Luca Pani and Simona Guerzoni

Toxins 2023, 15(1), 59; https://doi.org/10.3390/toxins15010059 - 10 Jan 2023

Cited by 10 | Viewed by 3874

Abstract

OnabotulinumtoxinA (BT-A) is one of the few drugs approved for the preventive treatment of chronic migraine (CM). Despite this, some aspects of its mechanism of action are still a matter of debate, and the precise magnitude of BT-A effects needs to be completely [...] Read more.

OnabotulinumtoxinA (BT-A) is one of the few drugs approved for the preventive treatment of chronic migraine (CM). Despite this, some aspects of its mechanism of action are still a matter of debate, and the precise magnitude of BT-A effects needs to be completely elucidated. BT-A acts primarily upon trigeminal and cervical nerve endings, by inhibiting the release of inflammatory mediators such as calcitonin gene-related peptide, as well as reducing the insertion of ionotropic and metabotropic receptors into the neuronal membrane. These actions increase the depolarization threshold of trigeminal and cervical nerve fibers, thus reducing their activation. The central actions of BT-A are still a matter of debate: a retrograde axonal transport has been postulated, but not clearly assessed in humans. Clinically, the efficacy of BT-A in CM has been assessed by large, randomized placebo-controlled trials, such as the Phase 3 REsearch Evaluating Migraine Prophylaxis Therapy (PREEMPT) trials. Those results were also confirmed in a wide range of open-label studies, even for long-term periods. Recently, novel findings have led to a better understanding of its pharmacological actions and clinical usefulness in migraine prevention. This narrative review summarizes, updates and critically revises the available data on BT-A and its possible implementation in chronic migraine. Moreover, the current role of BT-A in CM treatment has been discussed. Full article

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

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14 pages, 1610 KiB

Open AccessArticle

Canadian Physicians’ Use of Intramuscular Botulinum Toxin Injections for Shoulder Spasticity: A National Cross-Sectional Survey

by Farris Kassam, Brendan Lim, Sadia Afroz, Ève Boissonnault, Rajiv Reebye, Heather Finlayson and Paul Winston

Toxins 2023, 15(1), 58; https://doi.org/10.3390/toxins15010058 - 10 Jan 2023

Cited by 4 | Viewed by 4513

Abstract

Spasticity of the upper extremity can result in severe pain, along with many complications that can impair a patient’s activities of daily living. Failure to treat patients with spasticity of the upper limb can result in a decrease in the range of motion [...] Read more.

Spasticity of the upper extremity can result in severe pain, along with many complications that can impair a patient’s activities of daily living. Failure to treat patients with spasticity of the upper limb can result in a decrease in the range of motion of joints and contracture development, leading to further restriction in daily activities. We aimed to investigate the practice patterns of Canadian physicians who utilize Botulinum toxin type-A (BoNT-A) injections in the management of shoulder spasticity. 50 Canadian Physical Medicine and Rehabilitation (PM&R) physicians completed a survey with an estimated completion rate of (36.23%). The demographics of the survey participants came from a variety of provinces, clinical settings, and patient populations. The most common muscle injected for shoulder adduction and internal rotation spasticity was the pectoralis major, this was followed by latissimus dorsi, pectoralis minor, subscapularis and teres major. Injection of BoNT-A for problematic post-stroke shoulder spasticity was common, with (81.48%) of participants responding that it was always or often used in their management of post-stroke spasticity (PSS). Dosing of BoNT-A demonstrated variability for the muscle injected as well as the type of toxin used. The goals of the patients, caregivers, and practitioners were used to help guide the management of these patients. As a result, the practice patterns of Canadian physicians who treat shoulder spasticity are varied, due to numerous patient factors. Future studies are needed to analyze optimal treatment patterns, and the development of algorithms to standardize care. Full article

(This article belongs to the Special Issue Botulinum Toxin: From Poison to Possible Treatment for Spasticity and Movement Disorder)

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13 pages, 4342 KiB

Open AccessArticle

A Novel EGFR Targeted Immunotoxin Based on Cetuximab and Type 1 RIP Quinoin Overcomes the Cetuximab Resistance in Colorectal Cancer Cells

by Nicola Landi, Vincenza Ciaramella, Sara Ragucci, Angela Chambery, Fortunato Ciardiello, Paolo V. Pedone, Teresa Troiani and Antimo Di Maro

Toxins 2023, 15(1), 57; https://doi.org/10.3390/toxins15010057 - 9 Jan 2023

Cited by 2 | Viewed by 2105

Abstract

Cetuximab is a monoclonal antibody blocking the epidermal growth factor receptor (EGFR) in metastatic colorectal cancer (mCRC). However, cetuximab treatment has no clinical benefits in patients affected by mCRC with KRAS mutation or in the presence of constitutive activation of signalling pathways acting [...] Read more.

Cetuximab is a monoclonal antibody blocking the epidermal growth factor receptor (EGFR) in metastatic colorectal cancer (mCRC). However, cetuximab treatment has no clinical benefits in patients affected by mCRC with KRAS mutation or in the presence of constitutive activation of signalling pathways acting downstream of the EGFR. The aim of this study was to improve cetuximab’s therapeutic action by conjugating cetuximab with the type 1 ribosome inactivating protein (RIP) quinoin isolated from quinoa seeds. A chemical conjugation strategy based on the use of heterobifunctional reagent succinimidyl 3-(2-pyridyldithio)propionate (SPDP) was applied to obtain the antibody-type 1 RIP chimeric immunoconjugate. The immunotoxin was then purified by chromatographic technique, and its enzymatic action was evaluated compared to quinoin alone. Functional assays were performed to test the cytotoxic action of the quinoin cetuximab immunoconjugate against the cetuximab-resistant GEO-CR cells. The novel quinoin cetuximab immunoconjugate showed a significant dose-dependent cytotoxicity towards GEO-CR cells, achieving IC₅₀ values of 27.7 nM (~5.0 μg/mL) at 72 h compared to cetuximab (IC₅₀ = 176.7 nM) or quinoin (IC₅₀ = 149.3 nM) alone assayed in equimolar amounts. These results support the therapeutic potential of quinoin cetuximab immunoconjugate for the EGFR targeted therapy, providing a promising candidate for further development towards clinical use in the treatment of cetuximab-resistant metastatic colorectal cancer. Full article

(This article belongs to the Special Issue Recent Advances in Ribosome-Inactivating Proteins and Related Lectins: Analytical Methods, Toxicology and Therapeutical Potential)

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12 pages, 1569 KiB

Open AccessArticle

Zearalenone (ZEN) and Its Metabolite Levels in Tissues of Wild Boar (Sus scrofa) from Southern Italy: A Pilot Study

by Consiglia Longobardi, Sara Damiano, Gianmarco Ferrara, Serena Montagnaro, Valentina Meucci, Luigi Intorre, Samanta Bacci, Luigi Esposito, Nadia Piscopo, Antonio Rubino, Antonio Raffaele, Salvatore Florio and Roberto Ciarcia

Toxins 2023, 15(1), 56; https://doi.org/10.3390/toxins15010056 - 9 Jan 2023

Cited by 6 | Viewed by 2469

Abstract

Zearalenone (ZEN) is a non-steroidal estrogenic mycotoxin produced by the fungi of the Fusarium genera, and is a contaminant of cereals and plant products. ZEN and its metabolites are considered endocrine disruptors, and could have various toxic effects on animals and humans. In [...] Read more.

Zearalenone (ZEN) is a non-steroidal estrogenic mycotoxin produced by the fungi of the Fusarium genera, and is a contaminant of cereals and plant products. ZEN and its metabolites are considered endocrine disruptors, and could have various toxic effects on animals and humans. In recent years, there has been a significant demographic increase in wild boar (Sus scrofa) in many mountainous and hilly areas of Italy, including the Campania region, mainly due to global climate change. The wild boar can be defined as a generalist and omnivorous species capable of varying its diet; therefore, it can play a role as an environmental bioindicator towards contaminants such as mycotoxins. This study was conducted to evaluate, for the first time, the concentrations of ZEN and its metabolites in the liver, kidney, and muscle of 82 wild boars shot in their habitat by hunters with hunting permits in different localities of Avellino province (Campania region, Southern Italy) from 2021 to 2022. The samples were collected and analyzed with an SPE clean-up and high-pressure liquid chromatography method with fluorescence detection. The results indicated that ZEN and α-Zearalenol were present in most of the samples, suggesting that a plan to monitor these mycoestrogens is essential to achieve the goals of “One Health”. Full article

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

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8 pages, 720 KiB

Open AccessCommunication

Mpp23Aa/Xpp37Aa Insecticidal Proteins from Bacillus thuringiensis (Bacillales: Bacillaceae) Are Highly Toxic to Anthonomus grandis (Coleoptera: Curculionidae) Larvae

by Jéssica A. de Oliveira, Bárbara F. Negri, Patricia Hernández-Martínez, Marcos F. Basso and Baltasar Escriche

Toxins 2023, 15(1), 55; https://doi.org/10.3390/toxins15010055 - 8 Jan 2023

Cited by 5 | Viewed by 2357

Abstract

The beetle Anthonomus grandis Boheman, 1843, is the main cotton pest, causing enormous losses in cotton. The breeding of genetically modified plants with A. grandis resistance is seen as an important control strategy. However, the identification of molecules with high toxicity to this [...] Read more.

The beetle Anthonomus grandis Boheman, 1843, is the main cotton pest, causing enormous losses in cotton. The breeding of genetically modified plants with A. grandis resistance is seen as an important control strategy. However, the identification of molecules with high toxicity to this insect remains a challenge. The susceptibility of A. grandis larvae to proteins (Cry1Ba, Cry7Ab, and Mpp23Aa/Xpp37Aa) from Bacillus thuringiensis Berliner, 1915, with toxicity reported against Coleopteran, has been evaluated. The ingestion of different protein concentrations (which were incorporated into an artificial diet) by the larvae was tested in the laboratory, and mortality was evaluated after one week. All Cry proteins tested exhibited higher toxicity than that the untreated artificial diet. These Cry proteins showed similar results to the control Cry1Ac, with low toxicity to A. grandis, since it killed less than 50% of larvae, even at the highest concentration applied (100 μg·g⁻¹). Mpp/Xpp proteins provided the highest toxicity with a 0.18 μg·g⁻¹ value for the 50% lethal concentration. Importantly, this parameter is the lowest ever reported for this insect species tested with B. thuringiensis proteins. This result highlights the potential of Mpp23Aa/Xpp37Aa for the development of a biotechnological tool aiming at the field control of A. grandis. Full article

(This article belongs to the Special Issue Bacillus thuringiensis: A Broader View of Its Biocidal Activity)

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15 pages, 3925 KiB

Open AccessArticle

CDT of Clostridioides difficile Induces MLC-Dependent Intestinal Barrier Dysfunction in HT-29/B6 Epithelial Cell Monolayers

by Lucas Heils, Martina Schneemann, Ralf Gerhard, Jörg-Dieter Schulzke and Roland Bücker

Toxins 2023, 15(1), 54; https://doi.org/10.3390/toxins15010054 - 7 Jan 2023

Cited by 4 | Viewed by 2971

Abstract

Background: Clostridioides difficile binary toxin (CDT) defines the hypervirulence of strains in nosocomial antibiotic-induced colitis with the highest mortality. The objective of our study was to investigate the impact of CDT on the intestinal epithelial barrier and to enlighten the underlying molecular mechanisms. Methods: [...] Read more.

Background: Clostridioides difficile binary toxin (CDT) defines the hypervirulence of strains in nosocomial antibiotic-induced colitis with the highest mortality. The objective of our study was to investigate the impact of CDT on the intestinal epithelial barrier and to enlighten the underlying molecular mechanisms. Methods: Functional measurements of epithelial barrier function by macromolecular permeability and electrophysiology were performed in human intestinal HT-29/B6 cell monolayers. Molecular analysis of the spatial distribution of tight junction protein and cytoskeleton was performed by super-resolution STED microscopy. Results: Sublethal concentrations of CDT-induced barrier dysfunction with decreased TER and increased permeability for 332 Da fluorescein and 4 kDa FITC-dextran. The molecular correlate to the functional barrier defect by CDT was found to be a tight junction protein subcellular redistribution with tricellulin, occludin, and claudin-4 off the tight junction domain. This redistribution was shown to be MLCK-dependent. Conclusions: CDT compromised epithelial barrier function in a human intestinal colonic cell model, even in sublethal concentrations, pointing to barrier dysfunction in the intestine and leak flux induction as a diarrheal mechanism. However, this cannot be attributed to the appearance of apoptosis and necrosis, but rather to an opening of the paracellular leak pathway as the result of epithelial tight junction alterations. Full article

(This article belongs to the Special Issue Enterotoxins and Mucosal Pathomechanisms)

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16 pages, 4002 KiB

Open AccessArticle

Effects of Bacillus amyloliquefaciens XJ-BV2007 on Growth of Alternaria alternata and Production of Tenuazonic Acid

by Qinlan Jia, Yingying Fan, Shuaishuai Duan, Qiaomei Qin, Yu Ding, Min Yang, Yan Wang, Fengjuan Liu and Cheng Wang

Toxins 2023, 15(1), 53; https://doi.org/10.3390/toxins15010053 - 7 Jan 2023

Cited by 10 | Viewed by 3092

Abstract

Large amounts of processing tomato are grown in Xinjiang, China. Tomato black spot disease, caused by Alternaria spp., and the produced alternaria toxins in tomato products are posing risks to human health. In this study, we isolated a rhizospheric bacterium, XJ-BV2007, from tomato [...] Read more.

Large amounts of processing tomato are grown in Xinjiang, China. Tomato black spot disease, caused by Alternaria spp., and the produced alternaria toxins in tomato products are posing risks to human health. In this study, we isolated a rhizospheric bacterium, XJ-BV2007, from tomato (Solanum lycopersicum) fields, which we identified as Bacillus amyloliquefaciens. We found that this bacterium has a strong antagonistic effect against Alternaria alternata and reduces the accumulation of alternaria toxins in tomatoes. According to the antifungal activity of the bacteria-free filtrate, we revealed that B. amyloliquefaciens XJ-BV2007 suppresses A. alternata by the production of antifungal metabolites. Combining semi-preparative high-performance liquid chromatography, we employed UPLC-QTOF-MS analysis and the Oxford cup experiment to find that fengycin plays an important role in inhibiting A. alternata. This paper firstly reported that B. amyloliquefaciens efficiently controls tomato black spot disease and mycotoxins caused by A. alternata. B. amyloliquefaciens XJ-BV2007 may provide an alternative biocontrol strain for the prevention of tomato black spot disease. Full article

(This article belongs to the Special Issue Detoxification, Control, and Toxicological Studies on Mycotoxins through Biotechnological Approaches)

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15 pages, 2627 KiB

Open AccessArticle

Assessment of the Cytotoxicity, Mutagenicity, and Genotoxicity of Two Traditional Chinese Herbs: Aristolochia baetica and Magnolia officinalis

by Mélanie Poivre, Marie-Hélène Antoine, Kirill Kryshen, Anastasia Atsapkina, Alexander N. Shikov, Laure Twyffels, Amandine Nachtergael, Pierre Duez and Joëlle Nortier

Toxins 2023, 15(1), 52; https://doi.org/10.3390/toxins15010052 - 6 Jan 2023

Cited by 1 | Viewed by 2227

Abstract

Herbal remedies used in traditional medicine often contain several compounds combined in order to potentiate their own intrinsic properties. However, herbs can sometimes cause serious health troubles. In Belgium, patients who developed severe aristolochic acid nephropathy ingested slimming pills containing root extracts of [...] Read more.

Herbal remedies used in traditional medicine often contain several compounds combined in order to potentiate their own intrinsic properties. However, herbs can sometimes cause serious health troubles. In Belgium, patients who developed severe aristolochic acid nephropathy ingested slimming pills containing root extracts of an Aristolochia species, as well as the bark of Magnolia officinalis. The goal of the study was to evaluate, on a human renal cell line, Aristolochia and Magnolia extracts for their cytotoxicity by a resazurin cell viability assay, and their genotoxicity by immunodetection and quantification of the phosphorylated histone γ-H2AX. The present study also sought to assess the mutagenicity of these extracts, employing an OECD recognized test, the Ames test, using four Salmonella typhimurium strains with and without a microsomial fraction. Based on our results, it has been demonstrated that the Aristolochia–Magnolia combination (aqueous extracts) was more genotoxic to human kidney cells, and that this combination (aqueous and methanolic extracts) was more cytotoxic to human kidney cells after 24 and 48 h. Interestingly, it has also been shown that the Aristolochia–Magnolia combination (aqueous extracts) was mutagenic with a TA98 Salmonella typhimurium strain in the presence of a microsomial liver S9 fraction. This mutagenic effect appears to be dose-dependent. Full article

(This article belongs to the Special Issue Plant Toxins and Phytotoxins: Toxicology, Pharmacology, Identification, and Application)

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17 pages, 1287 KiB

Open AccessArticle

Identification of Cyanobacteria and Its Potential Toxins in the Joanes I Reservoir, Bahia, Brazil

by Maria Teresa Araujo Pinheiro Menescal, Edna dos Santos Almeida, Emerson Andrade Sales, Annick Méjean and Claude Yéprémian

Toxins 2023, 15(1), 51; https://doi.org/10.3390/toxins15010051 - 6 Jan 2023

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Abstract

The Joanes I Reservoir is responsible for 40% of the drinking water supply of the Metropolitan Region of Salvador, Bahia, Brazil. For water sources such as this, there is concern regarding the proliferation of potentially toxin-producing cyanobacteria, which can cause environmental and public [...] Read more.

The Joanes I Reservoir is responsible for 40% of the drinking water supply of the Metropolitan Region of Salvador, Bahia, Brazil. For water sources such as this, there is concern regarding the proliferation of potentially toxin-producing cyanobacteria, which can cause environmental and public health impacts. To evaluate the presence of cyanobacteria and their cyanotoxins in the water of this reservoir, the cyanobacteria were identified by microscopy; the presence of the genes of the cyanotoxin-producing cyanobacteria was detected by molecular methods (polymerase chain reaction (PCR)/sequencing); and the presence of toxins was determined by liquid chromatography with tandem mass spectrometry (LC-MS/MS). The water samples were collected at four sampling points in the Joanes I Reservoir in a monitoring campaign conducted during the occurrence of phytoplankton blooms, and the water quality parameters were also analysed. Ten cyanobacteria species/genera were identified at the monitoring sites, including five potentially cyanotoxin-producing species, such as Cylindrospermopsis raciborskii, Cylindrospermopsis cf. acuminato-crispa, Aphanocapsa sp., Phormidium sp., and Pseudanabaena sp. A positive result for the presence of the cylindrospermopsin toxin was confirmed at two sampling points by LC-MS/MS, which indicated that the populations are actively producing toxins. The analysis of the PCR products using the HEPF/HEPR primer pair for the detection of the microcystin biosynthesis gene mcyE was positive for the analysed samples. The results of this study point to the worrisome condition of this reservoir, from which water is collected for public supply, and indicate the importance of the joint use of different methods for the analysis of cyanobacteria and their toxins in reservoir monitoring. Full article

(This article belongs to the Special Issue Prospective Studies in Survey and Biosurvey of Cyanotoxins In Situ)

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Toxins, Volume 15, Issue 1 (January 2023) – 80 articles

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