Toxicology and safety study of L-tryptophan and its impurities for use in swine.

L-tryptophan, an essential amino acid for physiological processes, metabolism, development, and growth of organisms, is widely utilized in animal nutrition and human health as a feed additive and nutritional supplement, respectively. Despite its known benefits, safety concerns have arisen due to an eosinophilia-myalgia syndrome (EMS) outbreak linked to L-tryptophan consumed by humans. Extensive research has established that the EMS outbreak was caused by an L-tryptophan product that contained certain impurities. Therefore, safety validations are imperative to endorse the use of L-tryptophan as a supplement or a feed additive. This study was conducted in tertiary hybrid [(Landrace × Yorkshire) × Duroc] pigs to assess general toxicity and potential risks for EMS-related symptoms associated with L-tryptophan used as a feed additive. Our investigation elucidated the relationship between L-tryptophan and EMS in swine. No mortalities or clinical signs were observed in any animals during the administration period, and the test substance did not induce toxic effects. Hematological analysis and histopathological examination revealed no changes in EMS-related parameters, such as eosinophil counts, lung lesions, skin lesions, or muscle atrophy. Furthermore, no test substance-related changes occurred in other general toxicological parameters. Through analyzing the tissues and organs of swine, most of the L-tryptophan impurities that may cause EMS were not retained. Based on these findings, we concluded that incorporating L-tryptophan and its impurities into the diet does not induce EMS in swine. Consequently, L-tryptophan may be used as a feed additive throughout all growth stages of swine without safety concerns.

Pyrrolizidine Alkaloids in Foods, Herbal Drugs, and Food Supplements: Chemistry, Metabolism, Toxicological Significance, Analytical Methods, Occurrence, and Challenges for Future.

Consumers are increasingly seeking natural alternatives to chemical compounds, including the use of dried aromatic plants as seasonings instead of salt. However, the presence of pyrrolizidine alkaloids (PAs) in food supplements and dried plants has become a concern because of their link to liver diseases and their classification as carcinogenic by the International Agency for Research on Cancer (IARC). Despite European Union (EU) Regulation (EU) 2023/915, non-compliance issues persist, as indicated by alerts on the Rapid Alert System for Food and Feed (RASFF) portal. Analyzing PAs poses a challenge because of their diverse chemical structures and low concentrations in these products, necessitating highly sensitive analytical methods. Despite these challenges, ongoing advancements in analytical techniques coupled with effective sampling and extraction strategies offer the potential to enhance safety measures. These developments aim to minimize consumer exposure to PAs and safeguard their health while addressing the growing demand for natural alternatives in the marketplace.

In vitro and in vivo genotoxicity evaluation of ALP1018, a nanomineral food supplement.

The use of nano-based dietary supplements is increasing around the world, as nanotechnology can help enhance nutrient bioavailability. ALP1018 is a newly developed iron-zinc complex supplement designed as a nanoformulation to improve the efficacy of iron and zinc supplementation. However, safety concerns have been raised, as there is no clear evaluation of ALP1018 toxicity. The goal of this study was to determine the potential mutagenicity and genotoxicity of ALP1018 through three standard screenings: the Ames test, which evaluates bacterial reverse mutations; the in vitro test of chromosomal aberration in Chinese hamster lung cells; and the in vivo micronucleus assay using ICR mice. ALP1018 showed no mutagenic effect, as no increase was observed in the presence or absence of metabolic activation (S9 mix) in revertant colonies on all the bacterial strains used in the Ames test. No structural chromosomal abnormalities were observed in the presence or absence of the S9 mix in mammalian cells used in the chromosomal aberration assay. In the micronucleus test, the frequency of micronucleated polychromatic erythrocytes was not significantly increased in mouse bone marrow cells. Based on these findings, we can conclude that ALP1018 is safe to use and has no mutagenic or genotoxic potential.

Lack of genotoxicity potential and safety assessment of 4-(2-hydroxyethyl) morpholine present as an impurity in pharmaceuticals and nutritional supplements.

4-(2-Hydroxyethyl) morpholine (HEM) is widely used as a building block of macromolecules in the manufacture of pharmaceuticals and dietary supplements and could remain as an impurity in the finished products. An evaluation of HEM was conducted to identify endpoints that could be used to determine the point-of-departure (POD) for use in assessing the potential risk from exposure to HEM. No oral repeated dose toxicological studies of appropriate duration were found for HEM. Therefore, suitable analogue(s) were identified. Although oral repeated dose studies were available for the analogues, the studies were not of sufficient duration for use in the assignment of a POD for risk evaluation. Accordingly, the Threshold of Toxicological Concern (TTC) approach, which proposes that a de minimis value can be derived to qualitatively assess risk, was considered for HEM. To determine the appropriate TTC approach (genotoxic or non-genotoxic), the genotoxicity of HEM and its analogues were evaluated. The weight of the evidence indicated that HEM, and the appropriate analogues, are not genotoxic. Considering the chemical structure of HEM, the non-genotoxic Cramer class III TTC value of 1.5 µg/kg bw/day was determined to be appropriate for use in safety assessment of HEM as an impurity in products intended for human consumption.

Marketable 1,3-dimethylamylamine and caffeine-based thermogenic supplements: Regulatory genotoxicity assessment through in vitro and in silico approaches.

The consumption of dietary supplements to enhance physical performance has increased significantly in the last century, especially thermogenic pre-workout supplements. Nevertheless, this industry has faced criticism for inadequate safety measures surveillance in regulatory issues regarding their products. The aims of our study were to investigate two pre-workout supplements with respect to (1) mutagenicity utilizing Salmonella/microsome assay; (2) genotoxicity employing cytokinesis-block micronucleus (CBMN) assay protocols; and (3) hepatocytoxicity using WST cell proliferation, activities of lactate dehydrogenase (LDH) and alkaline phosphatase using human liver carcinoma (HepG2) and mouse fibroblast (F C3H) cells. Oxidative stress was determined through glutathione (GSH) measurement and in silico for predictions of pharmacokinetics and toxicity for the most abundant isolated substances present in these supplements. Both supplements induced mutagenicity in all examined bacterial strains, especially in the presence of exogenous metabolism. Further, tested supplements significantly elevated the formation of micronuclei (MN) as well as other cellular phenomena. Concentration- and time-dependent curves were observed for hepatotoxicity in both studied cell lines. In addition, both supplements decreased levels of intracellular and extracellular GSH. In silico predictions showed that the isolated individual compounds failed to induce the observed outcomes. Our findings provide contributions to the molecular mechanisms underlying two pre-workout supplement-induced toxicity and the need for surveillance.

Safety considerations for dietary supplement manufacturers in the United States.

Due to significant dietary supplement use in the US, product manufacturers must understand the importance of implementing a robust approach to establishing safety for all ingredients, including dietary ingredients, components, and finished dietary supplement products. Different regulatory pathways exist by which the safety of dietary ingredients can be established, and thus allowed to be marketed in a dietary supplement. For individual dietary ingredients, safety information may come from a variety of sources including history of safe use, presence of the ingredient in foods, and/or non-clinical and clinical data. On occasion safety data gaps are identified for a specific ingredient, particularly those of botanical origin. Modern toxicological methods and models can prove helpful in satisfying data gaps and are presented in this review. For finished dietary supplement products, issues potentially impacting safety to consider include claims, product labeling, overages, contaminants, residual solvents, heavy metals, packaging, and product stability. In addition, a safety assessment does not end once a product is marketed. It is important that manufacturers actively monitor and record the occurrence of adverse events reported in association with the use of their products, in accordance with the law. Herein, we provide a comprehensive overview of considerations for assessing dietary supplement safety.

Hepatotoxicity due to dietary supplements: state-of-the-art, gaps and perspectives.

Food supplements are products intended to complement the normal diet and consist of concentrated sources of nutrients or other substances with a nutritional or physiological effect. Although they are generally considered safe if the manufacturer's recommendations are followed, many of them have shown hepatotoxic properties. This can cause many diseases (e.g. steatohepatitis and cirrhosis) characterized by progressive damage and malfunction of the liver that in the long term can lead to death. A review of the literature was carried out to elucidate which dietary supplements have been associated with cases of hepatotoxicity in recent years, with emphasis on those relevant to the consumer and the new trends (e.g. cannabidiol). It has been reported that the supplements described as hepatotoxic are mainly of botanical origin (e.g. green tea or turmeric) and those used in sports (mainly anabolic androgenic steroids). There is a great variability of compounds described as causing liver damage, although sometimes it is not possible to identify them, because they are contaminants or adulterants of the products. In addition, the prevalence of toxic effects after the administration of supplements is difficult to define due to underreporting and the lack of specific studies. Globally regarding hepatotoxicity of dietary supplements, there is a paucity of well-conducted clinical trials on the efficacy of these compounds and the frequency of related liver damage, as the use of these products is largely uncontrolled.

Systemic subchronic toxicity and comparison of four selenium nutritional supplements by 90-day oral exposure in Sprague-Dawley rats.

To evaluate and compare the safety of four selenium supplements, namely Se-enriched peptides (SeP), yeast selenium (SeY), L-Se-methylselenocysteine (L-SeMc) and sodium selenite (Na2SeO3), the subchronic toxicity study was designed by 90-day gavage administration in Sprague-Dawley rats. The doses of SeP, SeY, L-SeMc and Na2SeO3 were 0.15, 0.30 and 0.60 mg/kg bw/day, with additional dose of 0.45 mg/kg L-SeMc (All dose calculated as Se). Symptoms like growling, hair loss and significant weight loss were found at 0.60 mg/kg of L-SeMc, but not in other groups. At the dose of 0.60 mg/kg, females in Na2SeO3, SeY and L-SeMc groups showed significant elevations in ALT and/or ALP. Pathologic manifestations such as bile duct hyperplasia and cholestasis were predominantly found in females at 0.6 mg/kg of L-SeMc and SeY groups, and in males at same dose of L-SeMc group showed marked testicular atrophy. 0.60 mg/kg of SeY and Na2SeO3, and 0.30, 0.45, 0.60 mg/kg of L-SeMc induced significant reductions in sperm motility rates, rapid movement and amount. In conclusion, the NOAEL of SeP, SeY, L-SeMc, Na2SeO3 was all 0.30 mg/kg for female, and 0.60, 0.30, 0.15 and 0.30 mg/kg for male respectively. Liver and reproductive organs are possible toxic target organs of hyper selenium.

Improving the rigor and utility of botanical toxicity studies: Recommended resources.

Interest in botanicals, particularly as dietary supplement ingredients, is growing steadily. This growth, and the marketing of new ingredients and combination products as botanical dietary supplements, underscores the public health need for a better understanding of potential toxicities associated with use of these products. This article and accompanying template outline the resources to collect literature and relevant information to support the design of botanical toxicity studies. These resources provide critical information related to botanical identification, characterization, pre-clinical and clinical data, including adverse effects and interactions with pharmaceuticals. Toxicologists using these resources should collaborate with pharmacognosists and/or analytical chemists to enhance knowledge of the botanical material being tested. Overall, this guide and resource list is meant to help locate relevant information that can be leveraged to inform on decisions related to toxicity testing of botanicals, including the design of higher quality toxicological studies.

A cross-sectional clinical study in women to investigate possible genotoxicity and hematological abnormalities related to the use of black cohosh botanical dietary supplements.

Black cohosh (BC; Actaea racemosa L.), a top-selling botanical dietary supplement, is marketed to women primarily to ameliorate a variety of gynecological symptoms. Due to widespread usage, limited safety information, and sporadic reports of hepatotoxicity, the Division of the National Toxicology Program (DNTP) initially evaluated BC extract in female rats and mice. Following administration of up to 1000 mg/kg/day BC extract by gavage for 90 days, dose-related increases in micronucleated peripheral blood erythrocytes were observed, along with a nonregenerative macrocytic anemia resembling megaloblastic anemia in humans. Because both micronuclei and megaloblastic anemia may signal disruption of folate metabolism, and inadequate folate levels in early pregnancy can adversely affect neurodevelopment, the DNTP conducted a pilot cross-sectional study comparing erythrocyte micronucleus frequencies, folate and B12 levels, and a variety of hematological and clinical chemistry parameters between women who used BC and BC-naïve women. Twenty-three women were enrolled in the BC-exposed group and 28 in the BC-naïve group. Use of any brand of BC-only supplement for at least 3 months was required for inclusion in the BC-exposed group. Supplements were analyzed for chemical composition to allow cross-product comparisons. All participants were healthy, with no known exposures (e.g., x-rays, certain medications) that could influence study endpoints. Findings revealed no increased micronucleus frequencies and no hematological abnormalities in women who used BC supplements. Although reassuring, a larger, prospective study with fewer confounders (e.g., BC product diversity and duration of use) providing greater power to detect subtle effects would increase confidence in these findings.

Hepatotoxicity due to herbal dietary supplements: Past, present and the future.

Dietary supplements (DS) constitute a widely used group of products comprising vitamin, mineral, and botanical extract formulations. DS of botanical or herbal origins (HDS) comprise nearly 30% of all DS and are presented on the market either as single plant extracts or multi-extract-containing products. Despite generally safe toxicological profiles of most products currently present on the market, rising cases of liver injury caused by HDS - mostly by multi-ingredient and adulterated products - are of particular concern. Here we discuss the most prominent historical cases of HDS-induced hepatotoxicty - from Ephedra to Hydroxycut and OxyELITE Pro-NF, as well as products with suspected hepatotoxicity that are either currently on or are entering the market. We further provide discussion on overcoming the existing challenges with HDS-linked hepatotoxicity by introduction of advanced in silico, in vitro, in vivo, and microphysiological system approaches to address the matter of safety of those products before they reach the market.

Dual effect of the herbal matcha green tea (Camellia sinensis L. kuntze) supplement in EA.hy926 endothelial cells and Artemia salina.

ETHNOPHARMACOLOGICAL RELEVANCE: Matcha green tea (Camellia sinensis) based-supplements have been widely used since they present a greater content of phenolic compounds than traditional green tea, which is popularly used in the treatment of diabetes. However, there are few studies on the effectiveness and safety of matcha supplements. AIM OF THE STUDY: This work aimed to evaluate the efficacy and safety of this supplement in endothelial cells (EA.hy926) in the hyperglycemic model and in vivo Artemia salina. MATERIALS AND METHODS: To assess the effect of Matcha herbal supplement (MHS), EA. hy926 endothelial cells were treated with 20 µg/mL of MHS for 24 h, in a hyperglycemic medium with 35 mM glucose. After treatment, cells were trypsinized and centrifuged at 4 °C and 47×g for 5 min. The pellet was used to determine the reaction products to thiobarbituric acid and the levels of nitric oxide. Electron transport chain activity and ATP levels were also evaluated. Intracellular pH, apoptosis, and mitochondrial membrane depolarization were evaluated by flow cytometry. MHS chemical characterization was performed by HPLC-UV and total phenolic content analysis. The evaluation of the antioxidant capacity of MHS was performed by 2,2-diphenyl-1-picrylhydrazyl radical scavenger assay. To determine the in vivo acute toxicity of MHS, an A. salina assay was conducted, using 0,2 mL of different concentrations of MHS (10, 50, 100, 250, 500, 750 and 1000 µg/mL). The LD50 values were obtained by interpolation of 50% (y = 50) of the dead individuals in the trend curves. RESULTS: Our data showed that MHS was able to avoid oxidative and nitrosative stress induced by hyperglycemia, demonstrating important antioxidant activity. However, it was observed that MHS reduced up to 90% the activity of the four-electron transport complexes, reducing the ATP production of the endothelial cells. In the toxicity assay performed in Artemia salina, MHS showed mild toxicity (LD50 = 0,4 mg/mL). The major compounds found in MHS were epigallocatechin gallate, epicatechin, rutin, kaempferol, and quercetin. CONCLUSIONS: This data draws attention to the fact that supplements with high content of phenolic compounds, capable of avoiding oxidative and nitrosative stress can have a dual effect and, simultaneously to antioxidant activity, can induce toxicity in different cell types.

Acute dose toxicity evaluation of the food supplement calcium 3-hydroxy-3-methylbutyrate (HMB) in female Sprague Dawley rats.

The leucine metabolite, 3-hydroxy-3-methylbutyrate (HMB), primarily utilized as the calcium salt (CaHMB) has become one of the most widely used supplements and food ingredients to promote muscle health. While both CaHMB and HMB free acid have published sub-chronic toxicity studies, and CaHMB has published studies on genotoxicity, data are lacking on the acute dosing of HMB which is important for regulatory and transportation classification as well as in cases of accidental overconsumption. Therefore, an acute oral toxicity study was conducted with CaHMB following OECD 420 guidelines. One rat was used in the dosage sighting study and four rats were used in the main study. In both studies, rats were given a single oral dose of 2000 mg/kg body weight by gavage and monitored for 14 days following the dosage for changes in body weight, clinical signs as noted in OECD 420, and at the end of the study a necropsy was conducted to determine any gross tissue abnormalities. The dosage of CaHMB administered resulted in no deaths, no significant adverse clinical signs, and no findings of lesions or abnormal tissues. Under the Global Harmonized System of classification, CaHMB was found to be in the least toxic Category 5 or non-toxic.

Toxicity assessment of watermelon seed supplemented diet in rats.

Health benefits have been attributed to the consumption of watermelon (Citrullus lanatus L.) seeds in sub-Saharan Africa and Asia but the potential toxicity especially on chronic use remains to be investigated. Here, diets containing watermelon seeds (WMSs) at 2.5% or 5% were eaten ad libitum daily for 21 d by male and female Wistar rats. Changes in body and organ (liver, kidney, brain, testis, and ovary) weights following diet supplementation were monitored. Biomarkers of organ injury, such as alanine aminotransferase (ALT), alkaline phosphatase (ALP), cholesterol (CHO), triglyceride (TRI), urea, and creatinine (CRE) were measured. WMS-formulated diet led to a decrease in body weight in male but not in female rats compared to the control group. Also, testes weight significantly increased, whereas a decrease in that of the ovaries was noted. Although the ingestion of WMS did not significantly alter the weights of the liver and brain, a trend toward reduction was noticed. No significant changes were observed for the serum levels of ALT, ALP, CHO, and TRI in all rats. However, the kidney may be targeted for toxicity as indicated by significant elevations in serum urea and CRE levels in male and female rats when compared to controls. Furthermore, the sperm morphology anomalies observed after WMS supplementation demonstrate the potentially detrimental effects of high consumption of the seeds on the male reproductive system. We conclude that WMSs at 2.5% or 5% dose in the diet may elicit negative effects in organs particularly on the kidney and testes in rats.

The Botanical Safety Consortium: A public-private partnership to enhance the botanical safety toolkit.

Botanical dietary supplement use is widespread and growing, therefore, ensuring the safety of botanical products is a public health priority. This commentary describes the mission and objectives of the Botanical Safety Consortium (BSC) - a public-private partnership aimed at enhancing the toolkit for conducting the safety evaluation of botanicals. This partnership is the result of a Memorandum of Understanding between the US FDA, the National Institute of Environmental Health Sciences, and the Health and Environmental Sciences Institute. The BSC serves as a global forum for scientists from government, academia, consumer health groups, industry, and non-profit organizations to work collaboratively on adapting and integrating new approach methodologies (NAMs) into routine botanical safety assessments. The objectives of the BSC are to: 1) engage with a group of global stakeholders to leverage scientific safety approaches; 2) establish appropriate levels of chemical characterization for botanicals as complex mixtures; 3) identify pragmatic, fit-for-purpose NAMs to evaluate botanical safety; 4) evaluate the application of these tools via comparison to the currently available safety information on selected botanicals; 5) and integrate these tools into a framework that can facilitate the evaluation of botanicals. Initially, the BSC is focused on oral exposure from dietary supplements, but this scope could be expanded in future phases of work. This commentary provides an overview of the structure, goals, and strategies of this initiative and insights regarding our first objectives, namely the selection and prioritization of botanicals based on putative toxicological properties.

Potential health risks surrounding ingredients of pre-workout and post-workout dietary supplements: a thorough label analysis / Potenciais riscos de saúde relacionados com ingredientes de suplementos alimentares de pré-treino e pós-treino: análise meticulosa de rótulos

ABSTRACT Objective Dietary supplements use is increasing. Dietary supplements may contain high doses of substances or dangerous ingredient combinations. This article aims to investigate, by analyzing dietary supplements labels, if there are any doping substances or dangerous amounts of any other component in the reviewed dietary supplements. Methods Several brands which possessed their supplements sorted in pre-workout and post-workout were analyzed. 40 dietary supplements with all ingredients described were included. The minimum and maximum dosages of dietary supplements were statistically described as Mean±SD. Results Citrus aurantium extract, Yohimbe extract, Garcinia cambogia extract and Maca root extract were reported in some of the analyzed dietary supplements. Regarding caffeine, the pre-workout group displayed higher mean caffeine (241±86mg) than the post-workout group (183±68mg), and the minimal mean dose was 226±84mg; meanwhile, the maximal mean dose was 242±88mg. Concerning creatine, the pre-workout group displayed lower mean creatine (3106±1079mg) than the post-workout group (4137±4177mg), and the minimal mean dose was 3167±1728mg; meanwhile, the maximal mean dose was 3917±3643mg. The salt content in the post-workout group displayed a much higher mean (2155±4486mg) than the pre-workout group (464±605mg), and the minimal mean dose was 1635±3930mg; meanwhile, the maximal mean dose was 1708±3926g. Conclusions No doping substances were reported in the dietary supplements, but consumption recommendations on the label could lead to excessive consumption of some not yet fully tested ingredients.

RESUMO Objetivo O uso de suplementos alimentares está a aumentar. Estes podem conter altas doses de substâncias ou combinações de ingredientes perigosas. Este artigo procura encontrar, analisando os rótulos dos produtos, se existem substâncias dopantes ou nocivas. Métodos Foram analisadas várias marcas cujos respectivos suplementos foram classificados em pré e pós-treino. Foram incluídos 40 suplementos com todos os ingredientes descritos. A respectiva dose mínima e máxima foi descrita estatisticamente como média ± DP. Resultados Extratos de Citrus aurantium, Yohimbe, Garcinia cambogia e raiz de Maca foram encontrados nos suplementos analisados. O grupo pré-treino apresentou maior média de cafeína (241±86mg) do que o grupo pós-treino (183±68mg), e a dose média mínima foi de 226±84mg, enquanto a dose média máxima foi de 242±88 mg. O grupo pré-treino apresentou menor média de creatina (3106±1079mg) do que o grupo pós-treino (4137±4177mg), e a dose média mínima foi de 3167±1728mg, enquanto a dose média máxima foi de 3917±3643mg. O grupo pós-treino apresentou uma maior média de sal (2155±4486mg) do que o grupo pré-treino (464±605mg), e a dose média mínima foi 1635±3930mg, enquanto a dose média máxima foi de 1708±3926mg. Conclusão Não foram encontradas substâncias dopantes nos suplementos, mas algumas recomendações de consumo nos rótulos poderão levar à sobredose de certos ingredientes menos testados.

Toxicological safety assessment of essential oils used as food supplements to establish safe oral recommended doses.

Essential oils (EOs) are increasingly consumed as food supplements. The few published recommended doses available generally lack details both on the methodology used and concentration limits for substances of concern, including genotoxic carcinogens. We propose a tiered approach based on the toxicological evaluation of maximized concentrations of each constituent present in the EO investigated. The genotoxic potential of each constituent is assessed using literature data or QSAR analyses. Genotoxic constituents are evaluated according to the methodology provided in the ICHM7 guideline. A Toxicological Reference Value (TRV) is associated to each non-genotoxic constituent, using one of the following methodologies (decision-tree successive steps): extraction from recognized databases or clinical studies, application of adequate safety factors to NOAELs established in animal studies, read-across analyses and when none was possible, TTC of Cramer classes. An EO recommended dose is considered safe when the safety margin (ratio between TRV and systemic exposure) for all constituents is all at least equal to 1. In conclusion, this methodology has proven to be robust to establish safe recommended doses for EOs used as food supplements, consistent with those publicly available, and avoiding unnecessary dedicated new animal testing.

Androstenedione (a Natural Steroid and a Drug Supplement): A Comprehensive Review of Its Consumption, Metabolism, Health Effects, and Toxicity with Sex Differences.

Androstenedione is a steroidal hormone produced in male and female gonads, as well as in the adrenal glands, and it is known for its key role in the production of estrogen and testosterone. Androstenedione is also sold as an oral supplement, that is being utilized to increase testosterone levels. Simply known as "andro" by athletes, it is commonly touted as a natural alternative to anabolic steroids. By boosting testosterone levels, it is thought to be an enhancer for athletic performance, build body muscles, reduce fats, increase energy, maintain healthy RBCs, and increase sexual performance. Nevertheless, several of these effects are not yet scientifically proven. Though commonly used as a supplement for body building, it is listed among performance-enhancing drugs (PEDs) which is banned by the World Anti-Doping Agency, as well as the International Olympic Committee. This review focuses on the action mechanism behind androstenedione's health effects, and further side effects including clinical features, populations at risk, pharmacokinetics, metabolism, and toxicokinetics. A review of androstenedione regulation in drug doping is also presented.

Dietary biotin supplementation increases proliferation pathways in mice testes without affecting serum follicle-stimulating hormone levels and stem cell factor expression.

Supplements containing pharmacological concentrations of biotin are commercially available. The mechanisms by which biotin at pharmacological concentrations exerts its action have been the subject of multiple investigations, particularly for biotin's medicinal potential and wide use for cosmetic purposes. Several studies have reported that biotin supplementation increases cell proliferation; however, the mechanisms involved in this effect have not yet been characterized. In a previous study, we found that a biotin-supplemented diet increased spermatogonia proliferation. The present study was focused on investigating the molecular mechanisms involved in biotin-induced testis cell proliferation. Male BALB/cAnNHsd mice were fed a control or a biotin-supplemented diet (1.76 or 97.7 mg biotin/kg diet) for eight weeks. Compared with the control group, the biotin-supplemented mice presented augmented protein abundance of the c-kit-receptor and pERK1/2Tyr204 and pAKTSer473, the active forms of ERK/AKT proliferation signaling pathways. No changes were observed in the testis expression of the stem cell factor and in the serum levels of the follicle-stimulating hormone. Analysis of mRNA abundance found an increase in cyclins Ccnd3, Ccne1, Ccna2; Kinases Cdk4, Cdk2; and E2F; and Sp1 & Sp3 transcription factors. Decreased expression of cyclin-dependent kinase inhibitor 1a (p21) was observed but not of Cdkn2a inhibitor (p16). The results of the present study identifies, for the first time, the mechanisms associated with biotin supplementation-induced cell proliferation, which raises concerns about the effects of biotin on male reproductive health because of its capacity to cause hyperplasia, especially because this vitamin is available in large amounts without regulation.

Drug-induced liver injury in Australia, 2009-2020: the increasing proportion of non-paracetamol cases linked with herbal and dietary supplements.

OBJECTIVE: To compare the characteristics and outcomes of drug-induced liver injury (DILI) caused by paracetamol and non-paracetamol medications, particularly herbal and dietary supplements. DESIGN: Retrospective electronic medical record data analysis. SETTING, PARTICIPANTS: Adults admitted with DILI to the Gastroenterology and Liver Centre at the Royal Prince Alfred Hospital, Sydney (a quaternary referral liver transplantation centre), 2009-2020. MAIN OUTCOME MEASURES: 90-day transplant-free survival; drugs implicated as causal agents in DILI. RESULTS: A total of 115 patients with paracetamol-related DILI and 69 with non-paracetamol DILI were admitted to our centre. The most frequently implicated non-paracetamol medications were antibiotics (19, 28%), herbal and dietary supplements (15, 22%), anti-tuberculosis medications (six, 9%), and anti-cancer medications (five, 7%). The number of non-paracetamol DILI admissions was similar across the study period, but the proportion linked with herbal and dietary supplements increased from 2 of 13 (15%) during 2009-11 to 9 of 19 (47%) during 2018-20 (linear trend: P = 0.011). Despite higher median baseline model for end-stage liver disease (MELD) scores, 90-day transplant-free survival for patients with paracetamol-related DILI was higher than for patients with non-paracetamol DILI (86%; 95% CI, 79-93% v 71%; 95% CI, 60-82%) and herbal and dietary supplement-related cases (59%; 95% CI, 34-85%). MELD score was an independent predictor of poorer 90-day transplant-free survival in both paracetamol-related (per point increase: adjusted hazard ratio [aHR], 1.19; 95% CI, 1.09-3.74) and non-paracetamol DILI (aHR, 1.24; 95% CI, 1.14-1.36). CONCLUSION: In our single centre study, the proportion of cases of people hospitalised with DILI linked with herbal and dietary supplements has increased since 2009. Ninety-day transplant-free survival for patients with non-paracetamol DILI, especially those with supplement-related DILI, is poorer than for those with paracetamol-related DILI.