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.

Investigation of the risk factors of anorectal malformations.

PURPOSE: To investigate the factors that influence the occurrence of anorectal malformations (ARMs). METHODS: From December 2018 to December 2019, 136 children treated for ARMs at the Children's Hospital of Chongqing Medical University were included in the case group. The control group consisted of children with intussusception or perianal abscesses. A uniform questionnaire was filled by the parents of the enrolled children. RESULTS: The birth weight of the cases was significantly lower than that of the controls (p < .01), and children with ARMs were more likely to be complicated with single umbilical artery (SUA) (p < .001). Maternal upper respiratory tract infection (adjusted odds ratio [ORadj ], 2.44; 95% confidence interval [CI], 1.29-4.63) and urogenital infection (ORadj , 2.67; 95% CI 1.11-6.38) during the first trimester of pregnancy, anemia during pregnancy (ORadj , 5.69; 95% CI, 1.01-32.07), and exposure to hazardous substances 6 months before pregnancy and during the first trimester of pregnancy (ORadj , 13.82; 95% CI, 3.86-49.35) are associated with increased risk of ARMs. Folic acid supplements (ORadj , 0.31; 95% CI, 0.14-0.65) and multivitamin (ORadj , 0.34; 95% CI, 0.15-0.79) had a protective effect on ARMs. Paternal drug use (ORadj , 9.17; 95% CI, 2.19-38.49) 6 months before their wives' conception increased the risk of ARMs. CONCLUSION: Maternal infection, anemia during pregnancy, and maternal hazardous substances exposure are possible risk factors for ARMs. Folic acid supplements and multivitamin can reduce the occurrence of ARMs. Meanwhile, paternal drug use may also be a risk factor for ARMs.

Vitamin supplementation in healthy patients: What does the evidence support?

This review, with handy tables, summarizes which vitamins offer proven benefits-and which don't.

Quality by design approach for the preparation of fat-soluble vitamins lipid injectable emulsion.

The fat-soluble vitamins lipid injectable emulsion, a parenteral supplement, commonly used for hospitalized patients to meet daily requirements of fat-soluble vitamins. This study attempts to reduce risk, improve the stability and safety of fat-soluble vitamins lipid injectable emulsion using a Quality by Design (QbD) approach. The quality target product profile and critical quality attributes were defined based on a comprehensive understanding of fat-soluble vitamins lipid injectable emulsions. The emulsions were prepared using a high-pressure homogenization method. Critical quality attributes (CQAs) were identified using risk assessment tools such as fishbone diagram and risk estimation matrix. The assay, mean droplet size, polydispersity index, zeta potential, and the volume-weighted percentage of fat greater than 5 µm (PFAT5) were identified as CQAs. Accordingly, three critical formulation and process parameters for the emulsions were the percentage of emulsifier, homogenization pressure, and homogenization recirculation. The design space was obtained via a design of experiment (DoE), and an optimum formulation was successfully prepared. All physicochemical attributes of the optimal formulation were within the design space (i.e., droplet size: 217.2 ±â€¯0.37 nm; polydispersity index: 0.115 ±â€¯0.012; PFAT5: less than 0.05%; zeta potential: -34.6 ±â€¯1.09 mV; and viscosity: 20.95 mPa at 0.1 s-1). The optimal formulation remained acceptable physicochemical stability at 25 ±â€¯2 °C/60% RH ±â€¯5% RH over a 12-month period. Safety of the optimal emulsion was evaluated as acceptable through the determination of lysophospholipid content and an in vitro hemolysis assay. In conclusion, an optimal lipid injectable emulsion for fat-soluble vitamins was successfully prepared using a QbD approach.

Life-threatening vitamin D intoxication due to intake of ultra-high doses in multiple sclerosis: A note of caution.

Knowledge about complications of chronic ultra-high dose vitamin D supplementation is limited. We report a patient with primary progressive multiple sclerosis (MS) who presented with generalized weakness caused by hypercalcemia after uncontrolled intake of more than 50,000 IU of cholecalciferol per day over several months. Various treatment strategies were required to achieve normocalcemia. However, renal function improved only partly and further progression of MS was observed. We conclude that patients need to be informed about the risks of uncontrolled vitamin D intake and neurologists need to be alert of biochemical alterations and symptoms of vitamin D toxicity.

A Vitamin E-Enriched Antioxidant Diet Interferes with the Acute Adaptation of the Liver to Physical Exercise in Mice.

Physical exercise is beneficial for general health and is an effective treatment for metabolic disorders. Vitamin E is widely used as dietary supplement and is considered to improve non-alcoholic fatty liver disease by reducing inflammation and dyslipidemia. However, increased vitamin E intake may interfere with adaptation to exercise training. Here, we explored how vitamin E alters the acute exercise response of the liver, an organ that plays an essential metabolic role during physical activity. Mice fed a control or an α-tocopherol-enriched diet were subjected to a non-exhaustive treadmill run. We assessed the acute transcriptional response of the liver as well as glucocorticoid signalling and plasma free fatty acids (FFA) and performed indirect calorimetry. Vitamin E interfered with the exercise-induced increase in FFA and upregulation of hepatic metabolic regulators, and it shifted the transcriptional profile of exercised mice towards lipid and cholesterol synthesis while reducing inflammation. Energy utilization, as well as corticosterone levels and signalling were similar, arguing against acute differences in substrate oxidation or glucocorticoid action. Our results show that high-dose vitamin E alters the metabolic and inflammatory response of the liver to physical exercise. The interference with these processes may suggest a cautious use of vitamin E as dietary supplement.

The vitamin B6 paradox: Supplementation with high concentrations of pyridoxine leads to decreased vitamin B6 function.

Vitamin B6 is a water-soluble vitamin that functions as a coenzyme in many reactions involved in amino acid, carbohydrates and lipid metabolism. Since 2014, >50 cases of sensory neuronal pain due to vitamin B6 supplementation were reported. Up to now, the mechanism of this toxicity is enigmatic and the contribution of the various B6 vitamers to this toxicity is largely unknown. In the present study, the neurotoxicity of the different forms of vitamin B6 is tested on SHSY5Y and CaCo-2 cells. Cells were exposed to pyridoxine, pyridoxamine, pyridoxal, pyridoxal-5-phosphate or pyridoxamine-5-phosphate for 24h, after which cell viability was measured using the MTT assay. The expression of Bax and caspase-8 was tested after the 24h exposure. The effect of the vitamers on two pyridoxal-5-phosphate dependent enzymes was also tested. Pyridoxine induced cell death in a concentration-dependent way in SHSY5Y cells. The other vitamers did not affect cell viability. Pyridoxine significantly increased the expression of Bax and caspase-8. Moreover, both pyridoxal-5-phosphate dependent enzymes were inhibited by pyridoxine. In conclusion, the present study indicates that the neuropathy observed after taking a relatively high dose of vitamin B6 supplements is due to pyridoxine. The inactive form pyridoxine competitively inhibits the active pyridoxal-5'-phosphate. Consequently, symptoms of vitamin B6 supplementation are similar to those of vitamin B6 deficiency.

Australasian society for parenteral and enteral nutrition (AuSPEN) adult vitamin guidelines for parenteral nutrition.

BACKGROUND AND OBJECTIVES: This work represents the second part of a progressive review of AuSPEN's 1999 Guidelines for Provision of Micronutrient Supplementation in adult patients receiving parenteral nutrition. METHODS AND STUDY DESIGN: A systematic literature review was undertaken and recommendations made based on the available evidence and with consideration to specific elements of the Australian and New Zealand (NZ) practice environment. The strength of evidence underpinning each recommendation was assessed. A multidisciplinary steering committee and external reviewers provided feedback on the guidelines. RESULTS: On review of the available literature it appears that the parenteral multivitamin preparations presently available in Australia and NZ are to sufficient avoid deficiency without causing toxicity in most clinical situations for adults receiving PN when provided regularly as part of the PN prescription. Vitamin D is the most vulnerable vitamin for the Australian and NZ PN population. CONCLUSIONS: Vitamins are an essential component of PN and should be provided from commencement for all patients receiving PN. With the exception of vitamin D, which is recommended to be monitored annually, routine monitoring of vitamin levels is unlikely to be necessary in patients receiving regular parenteral multivitamin preparations. Clinical judgement is an important element when assessing, prescribing and monitoring patients receiving PN. Areas requiring further research have been identified.

A Call to Action to Bring Safer Parenteral Micronutrient Products to the U.S. Market.

The American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) started an intensive review of commercially available parenteral vitamin and trace element (TE) products in 2009. The chief findings were that adult multi-TE products currently available in the United States (U.S.) provide potentially toxic amounts of manganese, copper, and chromium, and neonatal/pediatric multi-TE products provide potentially toxic amounts of manganese and chromium. The multivitamin products appeared safe and effective; however, a separate parenteral vitamin D product is needed for those patients on standard therapy who continue to be vitamin D depleted and are unresponsive to oral supplements. The review process also extended to parenteral choline and carnitine. Although choline and carnitine are not technically vitamins or trace elements, choline is an essential nutrient in all age groups, and carnitine is an essential nutrient in infants, according to the Food and Nutrition Board of the Institute of Medicine. A parenteral choline product needs to be developed and available. Efforts are currently under way to engage the U.S. Food and Drug Administration (FDA) and the parenteral nutrient industry so A.S.P.E.N.'s recommendations can become a commercial reality.

The role of vitamin D deficiency in cardiovascular disease: where do we stand in 2013?

The high worldwide prevalence of vitamin D deficiency is largely the result of low sunlight exposure with subsequently limited cutaneous vitamin D production. Classic manifestations of vitamin D deficiency are linked to disturbances in bone and mineral metabolism, but the identification of the vitamin D receptor in almost every human cell suggests a broader role of vitamin D for overall and cardiovascular health. The various cardiovascular protective actions of vitamin D such as anti-diabetic and anti-hypertensive effects including renin suppression as well as protection against atherosclerosis and heart diseases are well defined in previous experimental studies. In line with this, large epidemiological studies have highlighted vitamin D deficiency as a marker of cardiovascular risk. However, randomized controlled trials (RCTs) on vitamin D have largely failed to show its beneficial effects on cardiovascular diseases and its conventional risk factors. While most prior vitamin D RCTs were not designed to assess cardiovascular outcomes, some large RCTs have been initiated to evaluate the efficacy of vitamin D supplementation on cardiovascular events in the general population. When considering the history of previous disappointing vitamin RCTs in general populations, more emphasis should be placed on RCTs among severely vitamin D-deficient populations who would most likely benefit from vitamin D treatment. At present, vitamin D deficiency can only be considered a cardiovascular risk marker, as vitamin D supplementation with doses recommended for osteoporosis treatment is neither proven to be beneficial nor harmful in cardiovascular diseases.

Vitamin D supplementation: what's known, what to do, and what's needed.

The use of vitamin D supplements to prevent and treat a wide range of illnesses has increased substantially over the last decade. Epidemiologic evidence links vitamin D deficiency to autoimmune disease, cancer, cardiovascular disease, depression, dementia, infectious diseases, musculoskeletal decline, and more. The Institute of Medicine published an exhaustive report in 2010 that concluded that vitamin D supplementation for indications other than musculoskeletal health was not adequately supported by evidence and that most North Americans receive sufficient vitamin D from their diet and sun exposure. These conclusions are at odds with some clinical practice guidelines; thus, we sought to summarize the best available evidence regarding the benefits of vitamin D supplementation, to examine the potential risks, and to provide practical dosing advice. The adequacy of vitamin D stores is determined by measuring the 25-hydroxyvitamin D serum concentrations. The demarcations between deficiency (< 20 ng/ml), insufficiency (20-30 ng/ml), and optimal (30-80 ng/ml) serum concentrations are controversial. Vitamin D in doses of 800-5000 IU/day improve musculoskeletal health (e.g., reduces the rate of fractures and falls in older adults (aged ≥ 65 yrs). In patients with documented vitamin D deficiency, a cumulative dose of at least 600,000 IU administered over several weeks appears to be necessary to replenish vitamin D stores. Single large doses of 300,000-500,000 IU should be avoided. Vitamin D supplementation should not be offered routinely to other patient populations. Although results from some prospective clinical trials are promising, most have not been robustly designed and executed. The decision by young, otherwise healthy adults to take vitamin D in doses of 2000 IU/day or lower is unlikely to cause harm. For patients who are not at risk for developing vitamin D deficiency, sensible sun exposure is an inexpensive and enjoyable way to maintain vitamin D stores.

Increased 3-nitrotyrosine levels in mitochondrial membranes and impaired respiratory chain activity in brain regions of adult female rats submitted to daily vitamin A supplementation for 2 months.

Vitamin A supplementation among women is a common habit worldwide in an attempt to slow aging progression due to the antioxidant potential attributed to retinoids. Nonetheless, vitamin A elicits a myriad of side effects that result from either therapeutic or inadvertent intake at varying doses for different periods. The mechanism behind such effects remains to be elucidated. In this regard, we performed the present work aiming to investigate the effects of vitamin A supplementation at 100, 200, or 500IU/kgday(-1) for 2 months on female rat brain, analyzing tissue lipid peroxidation levels, antioxidant enzyme activities (both Cu/Zn-superoxide dismutase - SOD - and Mn-SOD); glutathione S-transferase (GST) and monoamine oxidase (MAO) enzyme activity; mitochondrial respiratory chain activity and redox parameters in mitochondrial membranes, as well as quantifying α- and ß-synucleins, ß-amyloid peptide(1-40), immunoglobulin heavy-chain binding protein/78kDa glucose-regulated protein (BiP/GRP78), receptor for advanced glycation end products (RAGE), D2 receptor, and tumor necrosis factor-α (TNF-α) contents in rat frontal cortex, hippocampus, striatum, and cerebellum. We observed increased lipid peroxidation marker levels, altered Cu/Zn-SOD and Mn-SOD enzyme activities, mitochondrial nitrosative stress, and impaired respiratory chain activity in such brain regions. On the other hand, we did not find any change in MAO and GST enzyme activities, and on α- and ß-synucleins, ß-amyloid peptide(1-40), GRP78/BiP, RAGE, D2 receptor, and TNF-α contents. Importantly, we did not observed any evidence regarding an antioxidant effect of such vitamin at low doses in this experimental model. The use of vitamin A as an antioxidant therapy among women needs to be reexamined.

Possible adverse effect of high delta-alpha-tocopherol intake on hepatic iron overload: enhanced production of vitamin C and the genotoxin, 8-hydroxy-2'- deoxyguanosine.

Excess hepatic iron generates reactive oxygen species that result in oxidative stress and oxidative damage to the liver. Vitamins have hitherto been considered to be a possible remedy. The aim of this study was to determine if high doses of delta-alpha-tocopherol supplementation in iron overload would ameliorate the oxidative stress. Four groups of 20 male Wistar albino rats were studied: group 1 (control) was fed normal diet, group 2 (Fe) 0.75% Ferrocene iron, group 3 (FV gp) 0.75% Ferrocene/delta-alpha-tocopherol (10x RDA), group 4 (V gp) normal diet/delta-alpha-tocopherol. After 12 months, serum iron, reduced glutathione, catalase, vitamin C, Oxygen Radical Absorbance Capacity, lipid peroxidation, 8-hydroxy-2'-deoxyguanosine (8-OHdG), aspartate transaminase (AST), and alanine transaminase (ALT) were measured. Vitamin C levels were: F gp = 5.04 +/- 0.09; FV gp = 5.85 +/- 0.13 (micromol/l) (p < 0.05). 8-hydroxy-2'-deoxyguanosine levels were: F gp = 143.6 +/- 6.4; FV gp = 179.2 +/- 18.2 (ng/ml) (p < 0.05). Oxidative liver damage, as determined by serum AST and ALT levels, was not attenuated by alpha-tocopherol. A positive correlation existed between vitamin C and 8-OHdG, suggesting possible delta-alpha-tocopherol toxicity.

Simultaneous induction of non-neoplastic and neoplastic lesions with highly proliferative hepatocytes following dietary exposure of rats to tocotrienol for 2 years.

It was recently shown that 1-year chronic exposure of rats to tocotrienol (TT) induced highly proliferative liver lesions, nodular hepatocellular hyperplasia (NHH), and independently increased the number of glutathione S-transferase placental form (GST-P)-positive hepatocytes. Focusing attention on the pathological intrinsic property of NHH, a 104-week carcinogenicity study was performed in male and female Wistar Hannover rats given TT at concentrations of 0, 0.4 or 2% in the diet. The high-dose level was adjusted to 1% in both sexes from week 51 because the survival rate of the high-dose males dropped to 42% by week 50. At necropsy, multiple cyst-like nodules were observed, as in the chronic study, but were further enlarged in size, which consequently formed a protuberant surface with a partly pedunculated shape in the liver at the high dose in both sexes. Unlike the chronic study, NHH was not always accompanied by spongiosis, and instead angiectasis was prominent in some nodules. However, several findings in the affected hepatocytes such as minimal atypia, no GST-P immunoreactivity and heterogeneous proliferation, implied that NHH did not harbor neoplastic characteristics from increased exposure despite sustained high cell proliferation. On the other hand, in the high-dose females, the incidence of hepatocellular adenomas was significantly higher than in the control. There was no TT treatment-related tumor induction in any other organs besides the liver. Thus, the overall data clearly suggested that NHH is successively enlarged by further long-term exposure to TT, but does not become neoplastic. In contrast, TT induces low levels of hepatocellular adenomas in female rats.

High-dosage pyridoxine-induced auditory neuropathy and protection with coffee in mice.

Auditory neuropathy (AN) is a hearing disorder characterized by an abnormal auditory brainstem response (ABR). This study examined experimental AN model induced in mice following increased dosages of pyridoxine. Induced AN was examined for < or =10 weeks following the last pyridoxine treatment. To assess AN, we evaluated the ABR, auditory middle latency response (AMLR), otoacoustic emission (OAE), and histochemical morphology of the auditory nerve. Pyridoxine-treated mice exhibited an increase in the hearing threshold shift and delayed latency of both ABR and AMLR in proportion to pyridoxine dosage. Additionally, the extent of auditory nerve fiber loss increased in a dose-dependent manner following pyridoxine intoxication. Coffee or trigonelline treatment ameliorated the hearing threshold shift, delayed latency of the auditory evoked potential, and improved sensory fiber loss induced by pyridoxine intoxication. The present findings demonstrate that high-dose pyridoxine administration can be used to produce a new mouse model for AN, and coffee or trigonelline as a main active compound of coffee extract can potentially facilitate recovery from pyridoxine-induced auditory neuropathy.

Beta-carotene degradation products - formation, toxicity and prevention of toxicity.

Carotenoids are widely used as important micronutrients in food. Furthermore, carotenoid supplementation has been used in the treatment of diseases associated with oxidative stress such as various types of cancer, inflammatory diseases or cystic fibrosis. However, in some clinical studies harmful effects have been observed, e.g. a higher incidence of lung cancer in individuals exposed to extraordinary oxidative stress. The causal mechanisms of harmful effects are still unclear. Carotenoid breakdown products (CBPs) including highly reactive aldehydes and epoxides are formed during oxidative attacks in the course of antioxidative action. We investigated the formation of CBPs by stimulated neutrophils (and at further conditions), tested the hypothesis that CBPs may exert mitochondriotoxicity and tried to prevent toxicity in the presence of members of the antioxidative network. Stimulated neutrophils are able to degrade beta-carotene and to generate a number of CBPs. Concerning mitochondriotoxicity, we found that CBPs strongly inhibit state 3 respiration of rat liver mitochondria at concentrations between 0.5 and 20 microM. This was true for retinal, beta-ionone, and for mixtures of cleavage/breakdown products. The inhibition of mitochondrial respiration was accompanied by a reduction in protein sulfhydryl content, decreasing GSH levels and redox state, and elevated accumulation of malondialdehyde. Changes in mitochondrial membrane potential favor functional deterioration in the adenine nucleotide translocator as a sensitive target. The presence of additional antioxidants such as alpha-tocopherol, ascorbic acid, N-acetyl-cysteine or others could mitigate mitochondriotoxicity. The findings reflect a basic mechanism of increasing the risk of cancer induced by carotenoid degradation products.

Retinoic acid induces apoptosis by a non-classical mechanism of ERK1/2 activation.

Even though RA is involved in differentiation and apoptosis of normal and cancer cells, being sometimes used as adjuvant in chemotherapy, its mechanisms of action involve multiple overlapping pathways that still remain unclear. Recent studies point out that RA exerts rapid and non-genomic effects, which are independent of RAR/RXR-mediated gene transcription. In this work, we reported that RA treatment for 24 h decreases cell viability, induces apoptosis dependent on caspase-3 activation, and activates the transcription factor AP-1 in cultured Sertoli cells. Moreover, RA induced a rapid and non-classical stimulation of ERK1/2. ERK1/2 activation was mediated by MEK1/2, and the protein synthesis inhibitor cycloheximide did not alter the pattern of RA-induced ERK1/2 phosphorylation. Pharmacological inhibition of MEK1/2-ERK1/2 pathway with UO126 blocked caspase-3 activation, decreased AP-1 binding to DNA and inhibited apoptosis. Overall, our data suggest that a rapid and non-genomic effect of RA upon MEK1/2-ERK1/2 pathway leads to caspase-3 activation and caspase-3-dependent apoptosis in cultured Sertoli cells. The non-canonical RA signaling presented in this work evokes new perspectives of RA action, which may play an important role in mediating early biological effects of RA modulating cell death in normal and tumor cells.

Oxidative stress in the hippocampus, anxiety-like behavior and decreased locomotory and exploratory activity of adult rats: effects of sub acute vitamin A supplementation at therapeutic doses.

Vitamin A participates in the maintenance of normal hippocampal function during embryonic and postnatal stages of the vertebrate life. Some works demonstrated that vitamin A metabolites impair learning and induce a depression-like behavior in mice, among other effects. Since vitamin A has prooxidant effects on other experimental models, we decided to investigate whether vitamin A can induce oxidative stress in the adult rat hippocampus. We analyzed the sub acute effects of therapeutic (1000 and 2500 I.U./kg) or excessive (4500 and 9000 I.U./kg) vitamin A doses on the hippocampal redox state, as well as on levels of anxiety, and locomotory and exploratory activity. Vitamin A supplementation induced lipid peroxidation, protein carbonylation, and oxidation of the protein thiol content in the rat hippocampus in all periods analyzed. Increased superoxide dismutase (SOD) activity and decreased catalase (CAT) activity were also observed, which gives rise to an imbalance in the principal cellular enzymatic antioxidant system. Then, our results show, for the first time, that vitamin A induced oxidative stress in the adult rat hippocampus, is anxiogenic, and decreases locomotion in and exploration of an open field.