Metabolites

14 pages, 2983 KiB

Open AccessArticle

Identification and Characterization of Two Se6OMTs from Stephania epigaea Offer Novel Insights into the Biosynthetic Pathway of Cepharanthine

by Jingyi Gan, Wenlong Shi, Qishuang Li, Xinyi Li, Xingyu Zhao, Junhao Tang, Ying Ma, Jian Wang, Shukun Gong, Xiaohui Ma and Juan Guo

Metabolites 2025, 15(2), 92; https://doi.org/10.3390/metabo15020092 (registering DOI) - 3 Feb 2025

Abstract

Background/Objectives: Stephania epigaea is a plant from the Menispermaceae family. Its root is an important traditional folk medicine, which is called Diburong in China. Diburong is rich in benzylisoquinoline alkaloids (BIAs), including cepharanthine, which has been demonstrated to exhibit significant anti-inflammatory, antiviral, antineoplastic, [...] Read more.

Background/Objectives: Stephania epigaea is a plant from the Menispermaceae family. Its root is an important traditional folk medicine, which is called Diburong in China. Diburong is rich in benzylisoquinoline alkaloids (BIAs), including cepharanthine, which has been demonstrated to exhibit significant anti-inflammatory, antiviral, antineoplastic, and anti-SARS-CoV-2 activities, as well as raising leukocytes. Cepharanthine is composed of (R)- and (S)-1-benzylisoquinoline alkaloid (1-BIA). (S)-norcoclaurine-6-O-methyltransferase (6OMT) is a rate-limiting enzyme in BIA biosynthesis. However, its role in the cepharanthine biosynthetic pathway, particularly with the (R) stereoisomer substrate, remains largely unexplored. This study aimed to identify Se6OMTs involved in the cepharanthine biosynthetic pathway and elucidate the O-methyltransferases (OMTs) responsible for the production of (R)- and (S)-stereoisomer BIAs. Methods: In this study, three OMTs were cloned from S. epigaea and functionally characterized using nine 1-BIAs of (R)- and (S)-configurations as substrates. Results: Two O-methyltransferases, Se6OMT1 and Se6OMT3, showed efficient catalytic activity at the C6 position of both (R)- and (S)-norcoclaurine. Furthermore, Se6OMT3 demonstrated high catalytic activity at the C7 and C4′ positions of other (R)- and (S)-configuration 1-BIAs, which resulted in the generation of multiple products. Conclusions: This study focused on 6OMT enzymes in S. epigaea, identifying Se6OMTs involved in the cepharanthine biosynthetic pathway, determining the OMTs involved in the production of (R)- and (S)-stereoisomer BIAs. This research provides valuable insights into the substrate promiscuity of Se6OMTs on (R)- and (S)-configured 1-BIAs in S. epigaea and highlights the genetic components necessary for the metabolic engineering and synthetic biology approaches to cepharanthine production. Full article

(This article belongs to the Section Plant Metabolism)

► Show Figures

Figure 1

13 pages, 709 KiB

Open AccessArticle

Endothelial Markers in Type 2 Diabetic Patients with Acute Decompensated Heart Failure: A Pilot Study

by Martin Jozef Péč, Jakub Jurica, Tomáš Bolek, Ingrid Škorňová, Monika Péčová, Marek Cingel, Simona Horná, Lucia Stančiaková, Ján Staško, Štefan Tóth, Juraj Sokol, Peter Galajda, Marián Mokáň and Matej Samoš

Metabolites 2025, 15(2), 91; https://doi.org/10.3390/metabo15020091 (registering DOI) - 3 Feb 2025

Abstract

Background: Impaired endothelial function has been associated with vascular complications in type 2 diabetes (T2D), but its role in T2D-related heart failure (HF) remains indeterminate. The aim of this study was to assess selected markers of endothelial function in T2D patients with acute [...] Read more.

Background: Impaired endothelial function has been associated with vascular complications in type 2 diabetes (T2D), but its role in T2D-related heart failure (HF) remains indeterminate. The aim of this study was to assess selected markers of endothelial function in T2D patients with acute decompensated HF. Methods: A pilot prospective study on patients with acute decompensated HF requiring in-hospital admission was carried out. The vascular endothelial growth factor (VEGF), intercellular adhesion molecule 1 (ICAM-1), and vascular cell adhesion molecule 1 (VCAM-1) were assessed at admission and after decongestion. Subsequently, differences in these markers between T2D and non-diabetic (ND) patients were studied. Results: In total, 39 patients (21 with T2D and 18 ND patients) were enrolled. Twenty-eight patients presented with preserved ejection fraction (EF), and 11 presented with reduced EF. Looking at the VEGF levels in T2D patients, on admission, a median of 233.0 pg/mL (1.7–598 pg/mL) was found compared to 106.0 pg/mL (1.7–888 pg/mL) in ND individuals; the differences reached statistical significance (p = 0.04). There were no significant differences in VEGF levels after decongestion, and in VCAM-1 (2237 ± 1195 vs. 2699 ± 1093 ng/mL, p = 0.37) and ICAM-1 (596 ± 268 vs. 638 ± 437 ng/mL, p = 0.79) levels between T2D and ND patients upon admission and after decongestion. The value of EF (preserved or reduced) affected the VEGF levels upon admission. Conclusions: This study identified significantly higher VEGF levels upon admission due to acute decompensated HF in T2D patients. Full article

(This article belongs to the Special Issue Exploring Pathological Mechanisms in Obesity, Diabetes, and Metabolic Syndrome)

► Show Figures

Figure 1

14 pages, 2062 KiB

Open AccessArticle

Exploring the Antineoplastic Properties of the Lebanese Jania rubens against Colorectal Cancer

by Mariam Rifi, Zeina Radwan, Nouha Sari-Chmayssem, Rayan Kassir, Ziad Fajloun, Abir Abdel Rahman, Marwan El-Sabban, Corinne Prévostel, Zeina Dassouki and Hiba Mawlawi

Metabolites 2025, 15(2), 90; https://doi.org/10.3390/metabo15020090 (registering DOI) - 2 Feb 2025

Abstract

Background/Objective: Colon cancer poses a significant health burden, with current treatments often associated with severe side effects and limited effectiveness for some patients. Natural products are gaining interest as adjuvant therapies, potentially reducing side effects and improving responses to conventional treatments. We previously [...] Read more.

Background/Objective: Colon cancer poses a significant health burden, with current treatments often associated with severe side effects and limited effectiveness for some patients. Natural products are gaining interest as adjuvant therapies, potentially reducing side effects and improving responses to conventional treatments. We previously highlighted the potent antineoplastic effects of organic extracts derived from the Lebanese red algae Jania rubens. This study, investigated the anticancer activities of polysaccharide, protein, and lipid extracts from J. rubens, which may serve as adjuvant therapies to enhance conventional treatments. Methods: we employed colorimetric assays, wound healing assays, and cell cycle analysis to evaluate the anticancer activities of the extracts. The polysaccharide extract was characterized for sulfate content and structure using barium chloride-gelatin and FT-IR methods. Results: All J. rubens extracts exhibited significant anticancer effects, with the polysaccharide extract showing particularly strong cytotoxicity, apoptosis induction, and antiproliferative and anti-migratory activities. Conclusion: These findings confirm that J. rubens is a source of bioactive compounds with anticancer potential. Further investigations are needed to elucidate the molecular pathways targeted by J. rubens extracts in cancer cells. Full article

(This article belongs to the Special Issue Advances in Secondary Metabolites: Phytochemical Analysis and Bioactivity Assays)

► Show Figures

Graphical abstract

17 pages, 665 KiB

Open AccessReview

Metabolic Syndrome Spectrum in Children with Classic Congenital Adrenal Hyperplasia—A Comprehensive Review

by Sanja Panic Zaric, Tatjana Milenkovic, Sladjana Todorovic, Katarina Mitrovic, Dimitrije Cvetkovic, Maja Cehic, Jelena Vekic, Katja Dumic and Rade Vukovic

Metabolites 2025, 15(2), 89; https://doi.org/10.3390/metabo15020089 (registering DOI) - 2 Feb 2025

Abstract

Children with a classic form of congenital adrenal hyperplasia (CCAH) have a potentially increased risk of unfavorable cardiometabolic events due to the interplay of corticosteroid treatment, hyperandrogenism, and other factors. Although readily recognized in adults, these aspects are frequently overlooked in children and [...] Read more.

Children with a classic form of congenital adrenal hyperplasia (CCAH) have a potentially increased risk of unfavorable cardiometabolic events due to the interplay of corticosteroid treatment, hyperandrogenism, and other factors. Although readily recognized in adults, these aspects are frequently overlooked in children and youth with CCAH; Aim: To review the evidence available from studies regarding cardiometabolic health outcomes in CCAH patients; Methods: A review of the literature was performed following PRISMA guidelines, including studies published between 2000 and 2024. We included studies reporting cardiometabolic outcomes in children and adolescents (<18 years) with CCAH. Where pediatric data were sparse, additional data were obtained from studies with older adolescents and young adults (15–25 years). Cardiometabolic outcomes included risk factors, such as obesity, insulin resistance, lipids, blood pressure, and vascular markers; Results: Twenty-five studies were analyzed. The prevalence of obesity was found to be higher in children with CCAH, as well as of increased visceral adiposity. Higher indices of insulin resistance were also a frequent finding in children with CCAH. CCAH patients had higher systolic blood pressure and more frequently loss of nocturnal blood pressure dipping, particularly among salt-wasting subtypes and in younger children. Subclinical atherosclerosis was indicated by increased carotid intima–media thickness, elevated hs-CRP, and impaired endothelial function. Other findings suggested changes in lipid profiles, particularly decreased HDL-c and increased triglycerides, although the findings were less consistent; Conclusions: Compared with the general pediatric population, children with CCAH were found to have an increase in multiple cardiometabolic risk factors. It is therefore vital to monitor these risk factors in pediatric CCAH, as well as tailoring treatment with cardiometabolic health in mind, to achieve better long-term cardiovascular and metabolic outcomes. Future research should focus on longitudinal studies of cardiometabolic outcomes and innovative therapeutic approaches to reduce these risks in patients with CCAH. Full article

(This article belongs to the Special Issue Obesity and Metabolic Syndrome in Children: Insights, Interventions and Emerging Perspectives)

► Show Figures

Figure 1

13 pages, 1614 KiB

Open AccessArticle

Clustering-Based Identification of BMI-Associated Metabolites with Mechanistic Insights from Network Analysis in Korean Men

by Jooyong Park, Jihyun Kang, Ji-Yeoun Lee, Daehee Kang, Joo-Youn Cho and Ji-Yeob Choi

Metabolites 2025, 15(2), 88; https://doi.org/10.3390/metabo15020088 (registering DOI) - 2 Feb 2025

Abstract

Background: Epidemiological studies using metabolomics often encounter challenges due to metabolite profiles being influenced by multiple modifiable behavioral factors, including regular exercise, smoking, drinking, and weight control. This study aimed to identify modifiable behavioral factors reflected in metabolites by clustering subjects based on [...] Read more.

Background: Epidemiological studies using metabolomics often encounter challenges due to metabolite profiles being influenced by multiple modifiable behavioral factors, including regular exercise, smoking, drinking, and weight control. This study aimed to identify modifiable behavioral factors reflected in metabolites by clustering subjects based on their metabolite profiles. Networks of metabolites were constructed to visualize their relationships and the differences between clustering groups. Methods: Sixty-four healthy men were included in this study. Information on regular exercise, smoking, and drinking was collected by questionnaires, and body mass index (BMI), an indicator of weight control, was calculated based on measured height and weight. Through targeted metabolomics, the concentrations of 149 metabolites were quantified. Subjects were clustered using the k-means method based on metabolite composition. Correlation-based networks were constructed for each cluster using Cytoscape software, followed by network analysis. Results: The subjects were divided into two clusters, with BMI identified as a distinguishing feature. Four lyso-phosphatidylcholines (PCs), six diacyl-PCs, and one acyl-alkyl-PC were positively associated with BMI. In the constructed network, acyl-alkyl-PCs exhibited the highest degrees, suggesting their central role in BMI-associated metabolic pathways. Conclusions: These findings suggest that metabolites can reflect behavioral factors, with BMI exerting a significant influence on metabolite profiles, particularly through its associations with phosphatidylcholines. Full article

(This article belongs to the Section Endocrinology and Clinical Metabolic Research)

► Show Figures

Figure 1

23 pages, 3870 KiB

Open AccessArticle

Separate and Combined Effects of Moderate-Intensity Exercise Training and Detraining with Protocatechuic Acid (PCA) on Myokines and Insulin-Signaling Pathways in Male Wistar Rats: A Preclinical Randomized Study

by Hira Shakoor, Jaleel Kizhakkayil, Yauhen Statsenko and Carine Platat

Metabolites 2025, 15(2), 87; https://doi.org/10.3390/metabo15020087 (registering DOI) - 1 Feb 2025

Abstract

Background: Exercise training positively modulates myokine secretion and improves glucose metabolism. Herein, we analyzed the effect of moderate-intensity training, detraining, and Protocatechuic Acid (PCA) supplementation on myokine secretions and regulation of insulin-signaling pathways. Methods: A five-arm study was conducted on 47 healthy [...] Read more.

Background: Exercise training positively modulates myokine secretion and improves glucose metabolism. Herein, we analyzed the effect of moderate-intensity training, detraining, and Protocatechuic Acid (PCA) supplementation on myokine secretions and regulation of insulin-signaling pathways. Methods: A five-arm study was conducted on 47 healthy male Wistar rats, trained at a moderate intensity level for four weeks (T0-T4). Animals were randomly classified into groups according to PCA supplementation and exercise durations: four weeks of Aerobic Training with or without PCA (AT4, AT4-PCA), eight weeks of Aerobic Training with or without PCA (AT8, AT8-PCA), and PCA Vehicle Control (VC). The animals were followed up until week 12 (T12). We decapitated six rats at T0 and T4, four rats per group at T8, and three rats per group at T12. Myokines (IGF-1, IL-6, FGF-21, myostatin, and irisin) were analyzed with ELISA. Western blot analysis measured protein expression of insulin-signaling pathways and GLUT-4 in the gastrocnemius muscle. Results: The IL-6 levels increased significantly (p < 0.01) with 8-week training in AT8 by 34% and AT8-PCA by 32%, compared to groups trained for only 4 weeks (AT4 and AT4-PCA). Similarly, the PI3K, and GLUT-4 expression improved in AT8 and AT8-PCA at T8. Training for 4 weeks improved IGF-1 levels, but a further 14% improvement was observed with 8-week training in AT8 at T8. Myostatin level significantly dropped by 27% even with 4-week training (p < 0.001). However, detraining increased the myostatin levels in all groups, but in AT8-PCA with PCA dose, myostatin reduced by 11% compared to AT8 at T12. PCA supplementation reduced the FGF-21 levels by 54% during detraining at T12 in AT8-PCA compared to AT8. However, the irisin level did not change markedly in any group. Conclusions: Physical training (with and without PCA) modulates myokine production and improves glucose metabolism, but the benefits are lost after detraining. Full article

(This article belongs to the Special Issue Diet and Nutrition in Relation to Metabolic Health)

► Show Figures

Graphical abstract

15 pages, 285 KiB

Open AccessReview

Metabolomics in Pathogenic Pathways and Targeted Therapies for Diabetic Neuropathy: A Comprehensive Review

by Cornelia Bala, Adriana Rusu, Dana Mihaela Ciobanu, Gabriela Roman and Anca Elena Crăciun

Metabolites 2025, 15(2), 86; https://doi.org/10.3390/metabo15020086 (registering DOI) - 1 Feb 2025

Abstract

Introduction and objective: This literature review aims to provide an overview of the progress in metabolomic assessment in animal and cell models and in humans with diabetic neuropathy (DN). Methods: Metabolomics has emerged as an important approach for investigating, identifying, and describing biomarkers [...] Read more.

Introduction and objective: This literature review aims to provide an overview of the progress in metabolomic assessment in animal and cell models and in humans with diabetic neuropathy (DN). Methods: Metabolomics has emerged as an important approach for investigating, identifying, and describing biomarkers related to DN. None has yet been validated for use in clinical practice. Results: DN induced significant alterations in energy metabolism and carbohydrates, lipids, amino acids, peptides, and proteins. Several treatments for DN, evaluated using metabolomics, were proved to have promising results. Conclusions: The ideal metabolite or set of metabolites that could be used as biomarkers should identify patients with diabetes prone to develop DN or those prone to progress to severe forms of sensory loss, associated with risk of ulcerations and amputation. Another potential use of a metabolite might be as an indicator of treatment response in clinical trials using agents with potential disease-modifying properties. Full article

(This article belongs to the Special Issue Diabetes and Metabolic Diseases: From Prevention to Clinical Management)

24 pages, 602 KiB

Open AccessReview

Optimised Skeletal Muscle Mass as a Key Strategy for Obesity Management

by Thomas M. Barber, Stefan Kabisch, Andreas F. H. Pfeiffer and Martin O. Weickert

Metabolites 2025, 15(2), 85; https://doi.org/10.3390/metabo15020085 (registering DOI) - 1 Feb 2025

Abstract

The ‘Body Mass Index’ (BMI) is an anachronistic and outdated ratio that is used as an internationally accepted diagnostic criterion for obesity, and to prioritise, stratify, and outcome-assess its management options. On an individual level, the BMI has the potential to mislead, including [...] Read more.

The ‘Body Mass Index’ (BMI) is an anachronistic and outdated ratio that is used as an internationally accepted diagnostic criterion for obesity, and to prioritise, stratify, and outcome-assess its management options. On an individual level, the BMI has the potential to mislead, including inaccuracies in cardiovascular risk assessment. Furthermore, the BMI places excessive emphasis on a reduction in overall body weight (rather than optimised body composition) and contributes towards a misunderstanding of the quiddity of obesity and a dispassionate societal perspective and response to the global obesity problem. The overall objective of this review is to provide an overview of obesity that transitions away from the BMI and towards a novel vista: viewing obesity from the perspective of the skeletal muscle (SM). We resurrect the SM as a tissue hidden in plain sight and provide an overview of the key role that the SM plays in influencing metabolic health and efficiency. We discuss the complex interlinks between the SM and the adipose tissue (AT) through key myokines and adipokines, and argue that rather than two separate tissues, the SM and AT should be considered as a single entity: the ‘Adipo–Muscle Axis’. We discuss the vicious circle of sarcopenic obesity, in which aging- and obesity-related decline in SM mass contributes to a worsened metabolic status and insulin resistance, which in turn further compounds SM mass and function. We provide an overview of the approaches that can mitigate against the decline in SM mass in the context of negative energy balance, including the optimisation of dietary protein intake and resistance physical exercises, and of novel molecules in development that target the SM, which will play an important role in the future management of obesity. Finally, we argue that the Adipo–Muscle Ratio (AMR) would provide a more clinically meaningful descriptor and definition of obesity than the BMI and would help to shift our focus regarding its effective management away from merely inducing weight loss and towards optimising the AMR with proper attention to the maintenance and augmentation of SM mass and function. Full article

(This article belongs to the Special Issue Obesity and Metabolic Health)

► Show Figures

Figure 1

30 pages, 6137 KiB

Open AccessArticle

Comprehensive Metabolomics Profiling and Bioactivity Study of Lycium shawii (Awsaj) Extracts with Particular Emphasis on Potential Anti-Malarial Properties

by Ruba Al-Nemi, Mutaz Akkawi, Khalid Sawalha, Siska Andrina Kusumastuti, Nuralih, Susi Kusumaningrum, Tia Okselni, Vania Chlarisa Situmorang, Abdi Wira Septama, Mariusz Jaremko and Abdul-Hamid Emwas

Metabolites 2025, 15(2), 84; https://doi.org/10.3390/metabo15020084 (registering DOI) - 1 Feb 2025

Abstract

Background/Objectives: Although malaria is one of the oldest known human diseases, it continues to be a major global health challenge. According to UNICEF, the global malaria mortality rate exceeded 600,000 annually in 2022, which includes more than 1000 children dying each day. This [...] Read more.

Background/Objectives: Although malaria is one of the oldest known human diseases, it continues to be a major global health challenge. According to UNICEF, the global malaria mortality rate exceeded 600,000 annually in 2022, which includes more than 1000 children dying each day. This study aimed to investigate the comprehensive chemical profile and biological activities, particularly the antimalarial activity, of Lycium shawii (Awsaj), a shrub traditionally used in the Arabian Peninsula, Middle East, India, and Africa to treat a myriad of ailments. Methods: Crude extracts of L. shawii were prepared using water, ethanol, methanol, and acetone. Nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) were utilized to perform untargeted metabolomics to maximize metabolite detection and tentatively identify bioactive phytochemicals. The total phenolic content (TPC) was measured for each extract, and bioassays were conducted to evaluate their antimalarial, antibacterial, and anti-inflammatory activities, particularly those of the water extract, which is the traditional method of consumption in Arabian folk medicine. Results: A total of 148 metabolites were detected, 45 of which were classified as phytochemicals. The bioassays revealed that the water extract that is traditionally used showed promising antimalarial potential by significantly inhibiting β-hematin formation in vitro at 1 mg/mL (with an absorbance of 0.140 ± 0.027). This is likely due to the rich presence of quinoline in the aqueous extract among several other bioactive phytochemicals, such as phenylpropanoids, alkaloids, flavonoids, and benzenoids. However, their anti-inflammatory and antibacterial activities were found to be weak, with only a minor inhibition of nitric oxide (NO) production in LPS-induced RAW 264.7 cells at a concentration of 500 µg/mL and weak antibacterial effects against pathogens like P. aeruginosa, MRSA, A. baumannii, and K. pneumoniae with an MIC of 500 μg/mL. The results also revealed that the methanolic extract had the highest TPC at 26.265 ± 0.005 mg GAE/g. Conclusions: The findings support the traditional medicinal use of L. shawii and highlight its potential as a source of novel therapeutic compounds, particularly for treating malaria. This study encourages further research to isolate and develop effective plant-based anti-malarial agents. Full article

(This article belongs to the Special Issue Secondary Metabolites and Their Activities: From the Identification to the Biological Investigation)

► Show Figures

Figure 1

17 pages, 2777 KiB

Open AccessArticle

Structural Analysis of Cardanol and Its Biological Activities on Human Keratinocyte Cells

by Shereen Basiouni, Nina Abel, Wolfgang Eisenreich, Helen L. May-Simera and Awad A. Shehata

Metabolites 2025, 15(2), 83; https://doi.org/10.3390/metabo15020083 - 30 Jan 2025

Abstract

Background/Objectives: Cashew nutshell liquid (CNSL) is obtained during the industrial processing of cashew nuts. It contains anacardic acid (2-hydroxy-6-n-pentadecylbenzoic acid) and cardanol (3-n-pentadecylphenol). Therefore, CNSL provides a rich source of phenolic lipids serving as natural antioxidants or precursors for industrial uses. Here, we [...] Read more.

Background/Objectives: Cashew nutshell liquid (CNSL) is obtained during the industrial processing of cashew nuts. It contains anacardic acid (2-hydroxy-6-n-pentadecylbenzoic acid) and cardanol (3-n-pentadecylphenol). Therefore, CNSL provides a rich source of phenolic lipids serving as natural antioxidants or precursors for industrial uses. Here, we have analyzed in detail a commercial sample of cardanol by nuclear magnetic resonance (NMR) spectroscopy and its biological activities in the human keratinocyte cell line (HaCaT cells). Methods: The cytotoxic effects, genotoxicity, cell proliferation, and healing properties on HaCaT cells were studied using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, comet assay, proliferation assay, and scratch assay, respectively. Additionally, the modulatory effect of cardanol on the cellular fatty acid profile of HaCaT cells was analyzed by gas chromatography. Results: NMR showed the structure of cardanol as a mixture of the 8′-monoene (42%), the 8′,11′-diene (22%), and the 8′,11′,14′-triene (36%) for the pentadecyl side chain with all double bonds in Z configuration. The cytotoxic effects on HaCaT cells only occurred at high concentrations of cardanol (>10 µg/mL), which caused significant reductions in cell viability. Using the comet assay, a dose-dependent increase in DNA damage was found at concentrations above 10 µg/mL. Scratch assays revealed that cardanol achieved 99% wound closure of HaCaT cells treated with 1 µg/mL cardanol after 48 h. Cardanol at 1 and 0.1 µg/mL significantly enhanced HaCaT cell proliferation and promoted migration, contributing to accelerated wound healing processes. As shown by gas chromatography, 1 µg/mL cardanol increased the total amount of polyunsaturated fatty acids (PUFA), including ω-3, ω-6, and ω-9 fatty acids. Conclusions: Together, these findings suggest that concentrations of <10 µg/mL cardanol are safe and exhibit beneficial biological activities, particularly wound-healing effects on HaCaT cells. Further studies are necessary to explore additional potential applications of cardanol, to refine its formulations for clinical use, and to ensure its safety and action in other target cells and species. Full article

(This article belongs to the Section Cell Metabolism)

14 pages, 3810 KiB

Open AccessArticle

Methimazole-Induced Hypothyroidism Increases the Content of Glycogen and Changes the Expression of LDH, GLUT4, and Aromatase in the Pregnant Uterus of Rabbits

by Marlen Espindola-Lozano, Maribel Méndez-Tepepa, Marlenne Castillo-Romano, Rubicela Rojas-Juárez, Leticia Nicolás-Toledo, Jorge Rodríguez-Antolín, Francisco Castelán and Estela Cuevas-Romero

Metabolites 2025, 15(2), 82; https://doi.org/10.3390/metabo15020082 - 30 Jan 2025

Abstract

Objective: To determine the impact of hypothyroidism on uterine glycogen accumulation during pregnancy. Methods: Non-pregnant and pregnant (days 5, 10, and 20) rabbits were grouped into control and methimazole (MMI) groups. In rabbits, serum concentrations of thyroxine (T4), triiodothyronine, glucose, insulin, [...] Read more.

Objective: To determine the impact of hypothyroidism on uterine glycogen accumulation during pregnancy. Methods: Non-pregnant and pregnant (days 5, 10, and 20) rabbits were grouped into control and methimazole (MMI) groups. In rabbits, serum concentrations of thyroxine (T4), triiodothyronine, glucose, insulin, progesterone, and estradiol were quantified. In uterine inter- and implantation sites, the glycogen content and expression of lactate dehydrogenase (LDH), GLUT4, and aromatase were quantified via Western blot. Fetuses’ characteristics at 20 days of pregnancy were analyzed. Two-way ANOVA was used to compare variables between groups. Results: Pregnancy reduced T4 concentrations but not T3. In virgin groups, MMI treatment significantly reduced the concentrations of T4 and T3 and increased the expression of GLUT4 and aromatase in the uterus compared to the control group. In pregnant groups, T4, T3, glucose, insulin, progesterone, and estradiol levels were similar between control and MMI-treated rabbits. Compared to controls, MMI treatment in pregnant rabbits (a) reduced GLUT4 expression on inter-implantation sites on day 5; (b) increased glycogen content on implantation sites but reduced GLUT4 expression on inter-and implantation sites on day 10; (c) increased glycogen content and LDH and aromatase expression but reduced GLUT4 on inter-implantation sites; and (d) increased glycogen content and the expression of LDH, GLUT4, and aromatase on day 20 on implantation sites. Moreover, the fetus characteristics were similar between groups. Conclusions: MMI-induced hypothyroidism is associated with changes in the uterine content of glycogen and the expression of LDH, GLUT4, and aromatase during pregnancy. Full article

(This article belongs to the Special Issue Glucose Metabolism in Pregnancy)

► Show Figures

Figure 1

19 pages, 4391 KiB

Open AccessArticle

Metabolomic and Transcriptomic Analyses Reveal the Factors Underlying Mature Fruit Pericarp Color Variations in the ‘Xinli No. 7’ Pear (Pyrus sinkiangensis)

by Yi Wang, Can Lu, Pan Yan, Shijie An, Ling Ma, Qiangqing Zheng, Yonghui Deng and Qiling Chen

Metabolites 2025, 15(2), 81; https://doi.org/10.3390/metabo15020081 - 30 Jan 2025

Abstract

Background/Objectives: The ‘Xinli No. 7’ pear is a new pear variety with the advantages of early ripening, high quality, high storage resistance, and a long shelf life. Peel color is an important appearance-related trait and an important indicator of fruit quality and [...] Read more.

Background/Objectives: The ‘Xinli No. 7’ pear is a new pear variety with the advantages of early ripening, high quality, high storage resistance, and a long shelf life. Peel color is an important appearance-related trait and an important indicator of fruit quality and commercial value. Methods: In this study, we investigated the polyphenol compound biosynthesis metabolic pathway in the fruit pericarp of ‘Xinli No. 7’ pear using metabolomic and transcriptomic approaches, and qRT–PCR was used for the relative expression analysis of 21 DEGs associated with flavonoid biosynthesis. Results: A total of 128 phenolic compounds were identified, along with 1850 differently expressed genes (DEGs) in peels of different colors. Caftaric acid, apigenin, astragalin, phlorizin, prunin, taxifolin, rutin, naringenin, and their derivatives were abundant in the peel of ‘Xinli No. 7’ pear. An integrated analysis of transcriptomic and metabolomic data revealed that one PGT1, one LAR, two ANS, three 4CL, one CHS, one DFR, and one CHI gene involved in flavonoid biosynthesis exhibited markedly different expression levels in the fruit pericarp of ‘Xinli No. 7’ pear. Metabolic profiling of pear skin led to the identification of polyphenol substances involved in the flavonoid biosynthetic process and revealed 16 flavonoid compounds with high accumulation in pear fruit with red skin (PR). Notably, MYBs (25), bHLHs (18), WRKYs (15), NACs (15), ERFs (15), and MADs (2) may also contribute to the accumulation of flavonoid metabolites and the biosynthesis of anthocyanins in the peel of ‘Xinli No. 7’. Conclusions: Therefore, our results demonstrate the key role of phenolic compounds and candidate transcription factors involved in the peel color formation of ‘Xinli No. 7’ pear fruit. Full article

(This article belongs to the Special Issue LC-MS/MS Analysis for Plant Secondary Metabolites)

► Show Figures

Figure 1

15 pages, 1801 KiB

Open AccessArticle

Is N1-Methylnicotinamide a Good Organic Cation Transporter 2 (OCT2) Biomarker?

by Anoud Sameer Ailabouni, Gautam Vijaywargi, Sandhya Subash, Dilip Kumar Singh, Zsuzsanna Gaborik and Bhagwat Prasad

Metabolites 2025, 15(2), 80; https://doi.org/10.3390/metabo15020080 - 29 Jan 2025

Abstract

Background/Objectives: The impact of potential precipitant drugs on plasma or urinary exposure of endogenous biomarkers is emerging as an alternative approach to evaluating drug–drug interaction (DDI) liability. N1-Methylnicotinamide (NMN) has been proposed as a potential biomarker for renal organic cation transporter 2 [...] Read more.

Background/Objectives: The impact of potential precipitant drugs on plasma or urinary exposure of endogenous biomarkers is emerging as an alternative approach to evaluating drug–drug interaction (DDI) liability. N1-Methylnicotinamide (NMN) has been proposed as a potential biomarker for renal organic cation transporter 2 (OCT2). NMN is synthesized in the liver from nicotinamide by nicotinamide N-methyltransferase (NNMT) and is subsequently metabolized by aldehyde oxidase (AO). Multiple clinical studies have shown a reduction in NMN plasma concentration following the administration of OCT inhibitors such as cimetidine, trimethoprim, and pyrimethamine, which contrasts with their inhibition of NMN renal clearance by OCT2. We hypothesized that OCT1-mediated NMN release from hepatocytes is inhibited by the administration of OCT inhibitors. Methods: Re-analysis of the reported NMN pharmacokinetics with and without OCT inhibitor exposure was performed. We assessed the effect of cimetidine on NMN uptake in OCT1-HEK293 cells and evaluated the potential confounding effects of cimetidine on enzymes involved in NMN formation and metabolism. Results: A re-analysis of previous NMN pharmacokinetic DDI data suggests that NMN plasma systemic exposure decreased by 17–41% during the first 4 h following different OCT inhibitor administration except dolutegravir. Our findings indicate that NMN uptake was significantly higher (by 2.5-fold) in OCT1-HEK293 cells compared to mock cells, suggesting that NMN is a substrate of OCT1. Additionally, our results revealed that cimetidine does not inhibit NNMT and AO activity. Conclusions: Our findings emphasize the limitations of using NMN as an OCT2 biomarker and reveal potential mechanisms behind the reduction in NMN plasma levels associated with OCT inhibitors. Instead, our data suggest that NMN could be tested further as a potential biomarker for OCT1 activity. Full article

(This article belongs to the Special Issue The Role of Metabolites in Translational and Clinical Pharmacology)

► Show Figures

Figure 1

25 pages, 1355 KiB

Open AccessArticle

Association of Trace Elements with Polycystic Ovary Syndrome in Women—A Case-Control Study

by Tinkara Srnovršnik, Bojana Pinter, Milena Horvat, Janja Snoj Tratnik, Ingrid Falnoga, Darja Mazej, Ivan Verdenik and Irma Virant-Klun

Metabolites 2025, 15(2), 79; https://doi.org/10.3390/metabo15020079 - 29 Jan 2025

Abstract

Objectives: There are still limited or lacking data on the association of trace elements (TEs) with polycystic ovary syndrome (PCOS). This case–control study aimed to determine levels of essential TEs (manganese (Mn), copper (Cu), zinc (Zn), selenium (Se), molybdenum (Mo)) and non-essential TEs [...] Read more.

Objectives: There are still limited or lacking data on the association of trace elements (TEs) with polycystic ovary syndrome (PCOS). This case–control study aimed to determine levels of essential TEs (manganese (Mn), copper (Cu), zinc (Zn), selenium (Se), molybdenum (Mo)) and non-essential TEs (arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb)) in urine, whole blood, and serum to investigate a possible association with kidney and liver function, endocrine and metabolic parameters, and environmental and lifestyle sources of potential exposure and provide possible recommendations. Methods: In our case–control study, women with PCOS (n = 35) and healthy controls (n = 35) underwent clinical and ultrasonographic examination, filled in questionnaires targeting general, lifestyle, and environmental information, and provided fasting venous blood samples and first morning urine for biochemical, hormonal, and TE analysis. Multiple linear regression models were used to evaluate the association between TE levels and data obtained through questionnaires. Results: In women with PCOS, lower Mo levels in whole blood (p = 0.024) and serum (p = 0.011) and higher serum Cu levels (p = 0.026) were detected when compared to healthy controls. Results of this study show that amendments in Cu and Mo levels might be related to altered kidney and liver function and disrupted hormonal balance in PCOS women. Cu levels positively correlated with leukocyte count. There was a negative correlation of Mo levels with proteinuria and luteinizing hormone levels. Regarding liver function, Mo negatively correlated with urinary bilirubin levels, and there was a positive association with alanine and aspartate aminotransferase, respectively. Dietary supplement consumption and certain diet habits appeared to be important predictors of exposure to Cu (beef consumption) or Mo (cereal and boiled vegetable consumption) and modify Mo and Cu levels in women. Conclusions: Concentrations of the chemical elements Mo and Cu in biological samples of women appear to be related to PCOS and nutrition. To our knowledge, this is a novel finding for Mo. Additional research is needed to provide more insights into the causality of the PCOS relationship with Mo and Cu in humans. Full article

(This article belongs to the Special Issue Trace Metal Element Metabolism in Biological Systems)

► Show Figures

Figure 1

24 pages, 625 KiB

Open AccessReview

Vitamins and Celiac Disease: Beyond Vitamin D

by Matteo Scarampi, Caterina Mengoli, Emanuela Miceli and Michele Di Stefano

Metabolites 2025, 15(2), 78; https://doi.org/10.3390/metabo15020078 - 28 Jan 2025

Abstract

Celiac disease is a chronic inflammatory condition of the small bowel caused, in genetically predisposed subjects, by the ingestion of gluten and characterised by a broad clinical polymorphism, ranging from patients with an asymptomatic or paucisymptomatic disease. The clinical presentation ranges from the [...] Read more.

Celiac disease is a chronic inflammatory condition of the small bowel caused, in genetically predisposed subjects, by the ingestion of gluten and characterised by a broad clinical polymorphism, ranging from patients with an asymptomatic or paucisymptomatic disease. The clinical presentation ranges from the presence of minor, apparently unrelated symptoms or first-degree kinship with known patients to severe intestinal malabsorption and all its clinical consequences and complications. Even if a large body of research improved our understanding of the molecular basis of celiac disease pathophysiology, enhancing the identification of new targets for future new treatments, an accurate gluten-free diet remains the mainstay of the therapy for this condition, restoring a normal absorptive mucosa. It is very rare, nowadays, to deal with patients with severe malabsorption syndrome secondary to celiac disease. Consequently, physicians are currently less prone to search for nutritional deficiencies in celiac disease. To pinpoint the possibility of both a disease-related and a diet-induced vitamin deficiency, we reviewed the literature on vitamin deficiency in this condition and reported the impact both in untreated and treated patients with celiac disease. A gluten-free diet must be tailored for each patient to meet nutritional targets: the pre-existence or diet-induced intake inadequacies should be carefully considered for an effective management of celiac disease. Full article

(This article belongs to the Special Issue Diet and Nutrition in Relation to Metabolic Health)

19 pages, 924 KiB

Open AccessArticle

Differences in Metabolite Profiles and Bioactivities of Intra-Strain Variants of Marine Fungus Penicillium antarcticum KMM 4668

by Gleb V. Borkunov, Natalya N. Kirichuk, Viktoria E. Chausova, Roman S. Popov, Olesya I. Zhuravleva, Ekaterina A. Chingizova, Ekaterina A. Yurchenko, Marina P. Isaeva and Anton N. Yurchenko

Metabolites 2025, 15(2), 77; https://doi.org/10.3390/metabo15020077 - 27 Jan 2025

Abstract

Background. During the cultivation of the marine fungus KMM 4668 on solid agar medium, the morphological instability of the strain was observed. As a result of the selection work, five intra-strain variants, named KMM 4711, KMM 4712, KMM 4713, KMM 4714, and KMM [...] Read more.

Background. During the cultivation of the marine fungus KMM 4668 on solid agar medium, the morphological instability of the strain was observed. As a result of the selection work, five intra-strain variants, named KMM 4711, KMM 4712, KMM 4713, KMM 4714, and KMM 4715, were obtained. Methods: The main objectives of this work were to compare the parent strain and its intra-strain variants using multi-locus phylogenetic analysis and to study the UPLC MS metabolite profiles and cytotoxic activities of their extracts. Results. A study of the original strain, KMM 4668, and its intra-strain variants using multi-locus phylogenetic analysis showed that they are sequence identical and belong to Penicillium antarcticum. UPLC MS metabolite profiling of fungal extracts revealed 20 compounds, including cladosporin-related polyketides, carotane sesquiterpenoids, andrastine meroterpenoids, and alkaloids. It was shown that the intra-strain variants KMM 4713 and KMM 4714 differed most strongly from the others in the increased production of cladosporin-related compounds, carotanoids, and the alkaloid chrysogin. In addition, the influence of fungal extracts on the viability of four mammalian cell lines was investigated. Conclusions. It has been shown that the intra-strain variants of P. antarcticum KMM 4668 may be promising sources of bioactive secondary metabolites. Full article

(This article belongs to the Section Microbiology and Ecological Metabolomics)

20 pages, 1722 KiB

Open AccessArticle

Hypoxia Dependent Inhibition of Glioblastoma Cell Proliferation, Invasion, and Metabolism by the Choline-Kinase Inhibitor JAS239

by Claire Louise Kelly, Martyna Wydrzynska, Marie M. Phelan, Sofya Osharovich, Edward J. Delikatny, Violaine Sée and Harish Poptani

Metabolites 2025, 15(2), 76; https://doi.org/10.3390/metabo15020076 - 26 Jan 2025

Abstract

Background: Elevated choline kinase alpha (ChoK) levels are observed in most solid tumors, including glioblastomas (GBM), and ChoK inhibitors have demonstrated limited efficacy in GBM models. Given that hypoxia is associated with resistance to GBM therapy, we hypothesized that tumor hypoxia could [...] Read more.

Background: Elevated choline kinase alpha (ChoK) levels are observed in most solid tumors, including glioblastomas (GBM), and ChoK inhibitors have demonstrated limited efficacy in GBM models. Given that hypoxia is associated with resistance to GBM therapy, we hypothesized that tumor hypoxia could be responsible for the limited response. Therefore, we evaluated the effects of hypoxia on the function of JAS239, a potent ChoK inhibitor in four GBM cell lines. Methods: Rodent (F98 and 9L) and human (U-87 MG and U-251 MG) GBM cell lines were subjected to 72 h of hypoxic conditioning and treated with JAS239 for 24 h. NMR metabolomic measurements and analyses were performed to evaluate the signaling pathways involved. In addition, cell proliferation, cell cycle progression, and cell invasion parameters were measured in 2D cell monolayers as well as in 3D cell spheroids, with or without JAS239 treatment, in normoxic or hypoxic cells to assess the effect of hypoxia on JAS239 function. Results: Hypoxia and JAS239 treatment led to significant changes in the cellular metabolic pathways, specifically the phospholipid and glycolytic pathways, associated with a reduction in cell proliferation via induced cell cycle arrest. Interestingly, JAS239 also impaired GBM invasion. However, effects from JAS239 were variable depending on the cell line, reflecting the inherent heterogeneity of GBMs. Conclusion: Our findings indicate that JAS239 and hypoxia can deregulate cellular metabolism, inhibit cell proliferation, and alter cell invasion. These results may be useful for designing new therapeutic strategies based on ChoK inhibition, which can act on multiple pro-tumorigenic features. Full article

(This article belongs to the Special Issue Mechanistic Insights into Metabolic Interactions with the Tumor Microenvironment)

16 pages, 2882 KiB

Open AccessArticle

Metabolome Alterations Associated with Three-Month Sitting-Time Reduction Among Sedentary Postmenopausal Latinas with Cardiometabolic Disease Risk

by Jeffrey S. Patterson, Paniz Jasbi, Yan Jin, Haiwei Gu, Matthew A. Allison, Chase Reuter, Brinda K. Rana, Loki Natarajan and Dorothy D. Sears

Metabolites 2025, 15(2), 75; https://doi.org/10.3390/metabo15020075 - 26 Jan 2025

Abstract

Background: Incidence of cardiometabolic disease among U.S. Hispanics/Latinos is higher than in non-Hispanic Whites. Prolonged sitting duration is prevalent in older adults, and compounded with menopause, greatly increases cardiometabolic risk in postmenopausal women. Metabolomic analyses of interventions to reduce sitting are lacking and [...] Read more.

Background: Incidence of cardiometabolic disease among U.S. Hispanics/Latinos is higher than in non-Hispanic Whites. Prolonged sitting duration is prevalent in older adults, and compounded with menopause, greatly increases cardiometabolic risk in postmenopausal women. Metabolomic analyses of interventions to reduce sitting are lacking and mechanistic understanding of health-promoting behavior change in postmenopausal Latinas is needed. Methods: To address this knowledge gap, an exploratory analysis investigated the plasma metabolome impact of a 12-week increased standing intervention among sedentary postmenopausal Latinas with overweight or obesity. From a parent-randomized controlled trial, a subset of Best Responders (n = 43) was selected using parameters of highest mean change in sitting bout duration and total sitting time; baseline variable-Matched Controls (n = 43) were selected using random forest modeling. Targeted LC-MS/MS analysis of archived baseline and 12-week plasma samples was conducted. Metabolite change was determined using a covariate-controlled general linear model and multivariate testing was performed. A false discovery rate correction was applied to all analyses. Results: Best Responders significantly changed time sitting (−110.0 ± 11.0 min; −21%), standing (104.6 ± 10.1 min; 40%), and sitting in bouts >30 min (−102.3 ± 13.9 min; −35%) compared to Matched Controls (7.1 ± 9.8 min, −7.8 ± 9.0 min, and −4.6 ± 12.7 min, respectively; all p < 0.001). Twelve-week metabolite change was significantly different between the two groups for 24 metabolites (FDR < 0.05). These were primarily related to amino acid metabolism, improved blood flow, and ATP production. Enzyme enrichment analysis predicted significant changes regulating glutamate, histidine, phenylalanine, and mitochondrial short-chain fatty acid catabolism. Pathway analysis showed significant intervention effects on glutamate metabolism and phenylalanine, tyrosine, and tryptophan biosynthesis, potentially indicating reduced cardiometabolic disease risk. Conclusions: Replacing nearly two hours of daily sitting time with standing and reduced prolonged sitting bouts significantly improved metabolomic profiles associated with cardiometabolic risk among postmenopausal Latinas. Full article

(This article belongs to the Special Issue The Emerging Role of Metabolomics in Epidemiological Studies of Atherosclerosis and Cardiovascular Disease)

► Show Figures

Figure 1

13 pages, 5516 KiB

Open AccessArticle

Effect of Four Different Initial Drying Temperatures on Biochemical Profile and Volatilome of Black Tea

by Zaifa Shu, Huijuan Zhou, Limin Chen, Yuhua Wang, Qingyong Ji and Weizhong He

Metabolites 2025, 15(2), 74; https://doi.org/10.3390/metabo15020074 - 25 Jan 2025

Abstract

Background: Black tea processing conditions significantly affect the final taste and flavor profiles, so researchers are now focusing on developing equipment and improving the appropriate processing conditions of major black tea varieties. Methods: Here, we tested the effect of four different initial drying [...] Read more.

Background: Black tea processing conditions significantly affect the final taste and flavor profiles, so researchers are now focusing on developing equipment and improving the appropriate processing conditions of major black tea varieties. Methods: Here, we tested the effect of four different initial drying temperatures, i.e., R65 (65 °C), R85 (85 °C), R105 (105 °C), and R125 (125 °C), on the sensory and biochemical profiles and volatilome of the black tea variety “Lishui wild” (LWV). Results: Our results indicate that both 85 and 105 °C are better than 65 and 125 °C for initial drying for 20 min. R105 had the highest sensory evaluation scores due to better shape, aroma, taste, leaf base, thearubigins, theanine, caffeine, and ratio of theaflavins + thearubigins to theaflavins. Both R85 and R105 had higher catechins than R65 and R125. The LWV volatilome consisted of esters (19.89%), terpenoids (18.95%), ketones (11.3%), heterocyclic compounds (9.99%), and alcohols (8.59%). In general, acids, aldehydes, amines, aromatics, ethers, hydrocarbons, phenols, sulfur compounds, and terpenoids accumulated in higher amounts in R85 and R105. The highly accumulated compounds in R105 were associated with green, fruity, sweet, woody, floral, hawthorn, mild, nutty, powdery, rose, and rosy flavors. The main pathways affected are secondary metabolites, sesquiterpenoid and triterpenoid biosynthesis, glycerolipid metabolism, zeatin biosynthesis, phenylpropanoid biosynthesis, ABC transport, glutathione metabolism, etc. Therefore, R105 can be used to achieve the optimal taste, flavor, and aroma of LWV. Conclusions: Overall, the presented data can be used by the tea industry for processing black tea with the most optimum volatile substances, catechins, theanine, amino acids, and other compounds. Full article

(This article belongs to the Section Plant Metabolism)

► Show Figures

Figure 1

Journal Description

Metabolites

Latest Articles

Journal Menu

Journal Browser

Highly Accessed Articles

Latest Books

E-Mail Alert

News

Topics

Conferences

Special Issues

Topical Collections

Further Information

Guidelines

MDPI Initiatives

Follow MDPI