SlimQuick™-Associated Hepatotoxicity Resulting in Fulminant Liver Failure and Orthotopic Liver Transplantation

Challenges in herbal-induced liver injury identification and prevention

Herbal and dietary supplements (HDS) are being used worldwide at an increasing rate. Mirroring this trend, HDS-induced liver injury, also known as HDS-induced liver injury (HILI), has increased significantly over the past three decades in the Drug-Induced Liver Injury Network (DILIN), now accounting for 20% of cases of drug-induced liver injury (DILI). There are significant challenges in the identification and prevention of HILI due to varying presentations, ability to make clear diagnosis, identification of the responsible ingredient, lack of treatment, and lack of regulatory oversight of HDS products to confirm their ingredients and ensure safety. The major implicated agents include anabolic steroids, green tea extract, garcinia cambogia, kratom, ashwagandha, turmeric and multi-ingredient nutritional supplements. Fortunately, with the formation of major DILI consortiums across the world, the last decade has seen advances in the identification of at-risk genetic phenotypes, the use of chemical analysis on multi-ingredient nutritional supplements, and the publication of data/injury patterns of potentially risky HDS.

A Comprehensive Review on the Use of Herbal Dietary Supplements in the USA, Reasons for Their Use, and Review of Potential Hepatotoxicity

Herbal and dietary supplement (HDS) use has grown exponentially in the United States. Unfortunately, the incidence of HDS-related liver injury has proportionally increased. Despite the potential for certain HDSs to cause clinically significant liver injury, they are not regulated by the Food and Drug Administration. Recent efforts have been made to regulate HDSs but are far removed from the scrutiny of prescription medications. Scant literature exists on HDSs and their risks of causing liver injury. In this comprehensive review, we examine trends of HDS use in the United States and the pathophysiologic mechanisms of drug-induced liver injury (DILI) of certain HDSs. Finally, we review usage rates; benefits, if any; purported pathophysiology of DILI; and propensity for progression to fulminant hepatic failure of nine HDSs linked to clinically significant DILI.

Liver Injury Caused by Green Tea Extract in PD-1-/- Mice: An Impaired Immune Tolerance Model for Idiosyncratic Drug-Induced Liver Injury

Idiosyncratic drug-induced liver injury (IDILI) is an idiosyncratic drug reaction that is specific to an individual and can lead to liver failure and even death. The mechanism of IDILI remains poorly understood, but most IDILI appears to be immune-mediated. We have developed the first validated animal model by using a PD-1^-/- mouse model in combination with anti-CTLA-4 to block immune checkpoints and impair immune tolerance. Treatment of these mice with drugs that cause IDILI in humans led to delayed-onset liver injury with characteristics similar to IDILI in humans. The current study investigates the effects of green tea extract, a weight-loss dietary supplement that has been reported to cause IDILI in humans. Green tea extracts contain a highly variable content of catechins including (-)-epigallocatechin gallate, the major catechin in green tea formulations. If the liver injury caused by green tea extract in humans is immune-mediated, it may occur in our impaired immune tolerance model. Female PD-1^-/- mice treated with anti-CTLA-4 antibody and green tea extract (500 mg/kg), a dose that is considered a no-observed-adverse-effect level for liver in rodents, produced a delayed onset increase in serum alanine transaminase levels and an increase in hepatic CD8⁺ T cells. In contrast, the response in male PD-1^-/- mice was less pronounced, and there was no evidence of liver injury in wild-type mice. These findings are consistent with the hypothesis that the IDILI caused by green tea extract is immune-mediated and is similar to IDILI caused by medications that are associated with IDILI.

United States Pharmacopeia (USP) comprehensive review of the hepatotoxicity of green tea extracts

As part of the United States Pharmacopeia's ongoing review of dietary supplement safety data, a new comprehensive systematic review on green tea extracts (GTE) has been completed. GTEs may contain hepatotoxic solvent residues, pesticide residues, pyrrolizidine alkaloids and elemental impurities, but no evidence of their involvement in GTE-induced liver injury was found during this review. GTE catechin profiles vary significantly with manufacturing processes. Animal and human data indicate that repeated oral administration of bolus doses of GTE during fasting significantly increases bioavailability of catechins, specifically EGCG, possibly involving saturation of first-pass elimination mechanisms. Toxicological studies show a hepatocellular pattern of liver injury. Published adverse event case reports associate hepatotoxicity with EGCG intake amounts from 140 mg to ∼1000 mg/day and substantial inter-individual variability in susceptibility, possibly due to genetic factors. Based on these findings, USP included a cautionary labeling requirement in its Powdered Decaffeinated Green Tea Extract monograph that reads as follows: "Do not take on an empty stomach. Take with food. Do not use if you have a liver problem and discontinue use and consult a healthcare practitioner if you develop symptoms of liver trouble, such as abdominal pain, dark urine, or jaundice (yellowing of the skin or eyes)."

Recent Advances on the Anti-Inflammatory and Antioxidant Properties of Red Grape Polyphenols: In Vitro and In Vivo Studies

In this review, special emphasis will be placed on red grape polyphenols for their antioxidant and anti-inflammatory activities. Therefore, their capacity to inhibit major pathways responsible for activation of oxidative systems and expression and release of proinflammatory cytokines and chemokines will be discussed. Furthermore, regulation of immune cells by polyphenols will be illustrated with special reference to the activation of T regulatory cells which support a tolerogenic pathway at intestinal level. Additionally, the effects of red grape polyphenols will be analyzed in obesity, as a low-grade systemic inflammation. Also, possible modifications of inflammatory bowel disease biomarkers and clinical course have been studied upon polyphenol administration, either in animal models or in clinical trials. Moreover, the ability of polyphenols to cross the blood-brain barrier has been exploited to investigate their neuroprotective properties. In cancer, polyphenols seem to exert several beneficial effects, even if conflicting data are reported about their influence on T regulatory cells. Finally, the effects of polyphenols have been evaluated in experimental models of allergy and autoimmune diseases. Conclusively, red grape polyphenols are endowed with a great antioxidant and anti-inflammatory potential but some issues, such as polyphenol bioavailability, activity of metabolites, and interaction with microbiota, deserve deeper studies.

The Role of Polyphenols in Human Health and Food Systems: A Mini-Review

This narrative mini- review summarizes current knowledge of the role of polyphenols in health outcomes-and non-communicable diseases specifically-and discusses the implications of this evidence for public health, and for future directions for public health practice, policy, and research. The publications cited originate mainly from animal models and feeding experiments, as well as human cohort and case-control studies. Hypothesized protective effects of polyphenols in acute and chronic diseases, including obesity, neurodegenerative diseases, type 2 diabetes, and cardiovascular diseases, are evaluated. Potential harmful effects of some polyphenols are also considered, counterbalanced with the limited evidence of harm in the research literature. Recent international governmental regulations are discussed, as the safety and health claims of only a few specific polyphenolic compounds have been officially sanctioned. The implications of food processing on the bioavailability of polyphenols are also assessed, in addition to the health claims and marketing of polyphenols as a functional food. Finally, this mini-review asserts the need for increased regulation and guidelines for polyphenol consumption and supplementation in order to ensure consumers remain safe and informed about polyphenols.

Risk of Liver Injury Associated with Green Tea Extract in SLIMQUICK(®) Weight Loss Products: Results from the DILIN Prospective Study

INTRODUCTION

Herbal and dietary supplements (HDS) have been increasingly recognized as a cause for acute liver injury (Navarro et al. Hepatology 60(4):1399-1408, 2014; Bailey et al. J Nutr 141:261-266, 2011). HDS products frequently contain numerous ingredients, and are marketed under various product names. A perusal of marketed weight loss products indicates that green tea extract (GTE) is a common ingredient in many. We aimed to describe the course and outcome of six patients who developed liver injury attributed to SLIMQUICK(®) weight loss products.

METHODS

Patients with suspected drug-induced liver injury were enrolled in a prospective study of the Drug-Induced Liver Injury Network (DILIN) and causality was assessed by a panel of hepatologists. During the period under study, 6 of 1091 cases of liver injury were attributed to a SLIMQUICK(®) product and were assigned causality scores of probable, highly likely, or definite.

RESULTS

Six cases of acute liver injury attributed to SLIMQUICK(®) products were enrolled in the DILIN prospective study between 2007 and 2011. All were women aged 22 to 58 years. Two had a normal body weight and four were mildly obese (body mass index 22.9-32.2 kg/m(2)). All were taking SLIMQUICK(®) products for weight loss and no patient reported prior use. Laboratory tests revealed a hepatocellular pattern of injury, with initial alanine aminotransferase (ALT) levels above 1000 U/L in all but one patient. Three patients were hospitalized and one underwent successful liver transplantation. No patients died of liver injury. GTE and/or its component catechins were listed among the ingredients for five of the six products.

CONCLUSIONS

SLIMQUICK(®) products can lead to severe acute hepatocellular liver injury, which may result in transplantation. Given the frequency of GTE as a component in weight loss products, this ingredient should be studied further as a possible cause for liver injury.

Potential role of the mitochondria as a target for the hepatotoxic effects of (-)-epigallocatechin-3-gallate in mice

Green tea and (-)-epigallocatechin-3-gallate (EGCG) have been studied for their obesity-related health effects. Many green tea extract (GTE)-based dietary supplements are commercially-available. Although green tea beverage has a long history of safe use, a growing number of case-reports have linked GTE-based supplements to incidents of hepatotoxicity. Animal studies support the hepatotoxic potential of GTE and EGCG, but the mechanisms remain unclear. Here, we examined the hepatotoxic effects of EGCG in C57BL/6J mice and evaluated changes in hepatic antioxidant response and mitochondria structure and function. Intragastric dosing with EGCG (500 - 750 mg/kg) once daily for 3 d caused hepatic inflammation, necrosis, and hemorrhage. Hepatotoxicity was associated with increased oxidative stress and decreased superoxide dismutase and glutathione peroxidase levels. Real-time PCR and transmission electron microscopy showed decreased hepatic mitochondria copy number in EGCG-treated mice. The mRNA levels of marker genes of respiratory complex I and III, sirtuin 3, forkhead box O3a, and peroxisome-EGCG-treated mice. Sirtuin 3 protein levels were also decreased by EGCG. Our data indicate the mitochondria may be a target for EGCG, and that inhibition of mitochondria function/antioxidant response may be important for the hepatotoxicity of bolus EGCG.

Liver toxicity related to herbs and dietary supplements: Online table of case reports. Part 2 of 5 series

BACKGROUND

No online current list of potentially life-threatening, hepatotoxic herbs and dietary supplements based on PubMed case reports exists in a summarized tabular form.

METHODS

Documented case reports of herbs or dietary supplements (DS; includes herbs) appearing to contribute to liver injury were used to create an online "DS Toxic Table" of potentially hepatotoxic herbs and dietary supplements (PubMed, 1966 to June, 2016, and cross-referencing). The spectrum of DS induced liver injuries (DSILI) included elevated liver enzymes, hepatitis, steatosis, cholestasis, hepatic necrosis, hepatic fibrosis, hepatic cirrhosis, veno-occlusive disease, acute liver failure requiring a liver transplant, and death.

RESULTS

Over the past 50 years, approximately 21 herbs (minus germander and usnic acid that are no longer sold) and 12 dietary supplements (minus the nine no longer sold and vitamin A & niacin due to excess intake) posed a possible risk for liver injures in certain individuals. The herbs with the most number of reported publications (but not cases studies) in descending order, were germander, black cohosh, kava extract, and green tea extract.

CONCLUSION

These online DS Toxic Tables will contribute to continued Phase IV post marketing surveillance to detect possible liver toxicity cases and serve to forewarn consumers, clinicians, and corporations.

Hepatotoxicity by Dietary Supplements: A Tabular Listing and Clinical Characteristics

Dietary supplements (DS) are extensively consumed worldwide despite unproven efficacy. The true incidence of DS-induced liver injury (DSILI) is unknown but is probably under-diagnosed due to the general belief of safety of these products. Reported cases of herbals and DS-induced liver injury are increasing worldwide. The aim of this manuscript is to report a tabular listing with a description of DS associated with hepatotoxicity as well as review the phenotype and severity of DSILI. Natural remedies related to hepatotoxicity can be divided into herbal product-induced liver injury and DS-induced liver injury. In this article, we describe different DS associated with liver injury, some of them manufactured DS containing several ingredients (Herbalife™ products, Hydroxycut™, LipoKinetix™, UCP-1 and OxyELITE™) while others have a single ingredient (green tea extract, linoleic acid, usnic acid, 1,3-Dimethylamylamine, vitamin A, Garcinia cambogia and ma huang). Additional DS containing some of the aforementioned ingredients implicated in liver injury are also covered. We have also included illicit androgenic anabolic steroids for bodybuilding in this work, as they are frequently sold under the denomination of DS despite being conventional drugs.

Hepatotoxicity of green tea: an update

Green tea (GT), obtained from the leaves of Camellia sinensis (L.) Kuntze (Fam. Theaceae), is largely used for its potential health benefits such as reduction in risk of cardiovascular diseases and weight loss. Nevertheless, it is suspected to induce liver damage. Present work reviews the hepatic adverse reactions associated with GT-based herbal supplements, published by the end of 2008 to March 2015. A systematic research was carried out on PubMed, MedlinePlus, Scopus and Google Scholar databases, without any language restriction. Moreover, some accessible databases on pharmacovigilance or phytovigilance were consulted. The causality assessment was performed using the CIOMS/RUCAM score. Nineteen cases of hepatotoxicity related to the consumption of herbal products containing GT were identified. The hepatic reactions involved mostly women (16/19); the kind of liver damage was generally classified as hepatocellular (16/19). The causality assessment between consumption of herbal preparation and hepatic reaction resulted as probable in eight cases and as possible in eleven cases. In seven cases, patients used preparations containing only GT, while twelve reactions involved patients who took multicomponent preparations (MC). The reactions induced by GT had a generally long latency (179.1 ± 58.95 days), and the outcome was always resolution, with recovery time of 64.6 ± 17.78 days. On the contrary, liver injury associated with MC had a shorter latency (44.7 ± 13.85 days) and was more serious in four cases that required liver transplantation and, when resolution occurred, the recovery time was longer (118.9 ± 38.79). MC preparations contained numerous other components, many of which are suspected to induce liver damage, so it is difficult to ascribe the toxicity to one specific component, e.g., GT. Present data confirm a certain safety concern with GT, even if the number of hepatic reactions reported is low considering the great extent of use of this supplement. The mechanism of GT hepatotoxicity remains unclear, but factors related to the patient are becoming predominant. A major safety concern exists when GT is associated with other ingredients that can interact between them and with GT, enhancing the risk of liver damage. Patients should be discouraged from using herbal or dietary supplements containing complex mixtures and should be encouraged to use herbal and dietary supplement possibly under supervision of healthcare professionals.