Traditional Chinese Medicine (TCM) and Herbal Hepatotoxicity: RUCAM and the Role of Novel Diagnostic Biomarkers Such as MicroRNAs

The Role of miRNAs in the Pathophysiology of Liver Diseases and Toxicity

Both acute and chronic liver toxicity represents a major global health burden and an important cause of morbidity and lethality worldwide. Despite epochal progress in the treatment of hepatitis C virus infections, pharmacological treatment strategies for most liver diseases are still limited and new targets for prevention or treatment of liver disease are urgently needed. MicroRNAs (miRNAs) represent a new class of highly conserved small non-coding RNAs that are involved in the regulation of gene expression by targeting whole networks of so called “targets”. Previous studies have shown that the expression of miRNAs is specifically altered in almost all acute and chronic liver diseases. In this context, it was shown that miRNA can exert causal roles, being pro- or anti-inflammatory, as well as pro- or antifibrotic mediators or being oncogenes as well as tumor suppressor genes. Recent data suggested a potential therapeutic use of miRNAs by targeting different steps in the hepatic pathophysiology. Here, we review the function of miRNAs in the context of acute and chronic liver diseases. Furthermore, we highlight the potential role of circulating microRNAs in diagnosis of liver diseases and discuss the major challenges and drawbacks that currently prevent the use of miRNAs in clinical routine.

MicroRNAs as biomarkers for liver injury: Current knowledge, challenges and future prospects

MicroRNAs (miRNAs) are short regulatory RNAs that are involved in various biological processes that regulate gene expression posttranscriptionally. Changes in miRNA expression can be detected in many physiological and pathological events, such as liver injury. Drug induced liver injury is a life threatening condition that frequently requires organ transplantation. Hepatotoxicity is also one of the major causes of drug failure in clinical trials and of drug withdrawal from the market. The profiling of miRNA expression shows great promise in monitoring liver injury, in the prediction of outcome in patients, and in the identification of liver-reactive compounds in toxicological assessment. Recent studies have demonstrated organ-specificity of some miRNAs (i.e., miR-122), which are released into biological fluids as a result of hepatocyte damage. This attests to the potential of miRNAs as noninvasive biomarkers to detect liver toxicity. This review presents information on miRNA signatures of hepatotoxicity and on the application of promising miRNA biomarkers in preclinical safety assessment. We further discuss the technical challenges associated with these emerging biomarkers for early diagnosis and detection of hepatotoxicity.

Hepatotoxicity of Herbal Supplements Mediated by Modulation of Cytochrome P450

Herbal supplements are a significant source of drug-drug interactions (DDIs), herb-drug interactions, and hepatotoxicity. Cytochrome P450 (CYP450) enzymes metabolize a large number of FDA-approved pharmaceuticals and herbal supplements. This metabolism of pharmaceuticals and supplements can be augmented by concomitant use of either pharmaceuticals or supplements. The xenobiotic receptors constitutive androstane receptor (CAR) and the pregnane X receptor (PXR) can respond to xenobiotics by increasing the expression of a large number of genes that are involved in the metabolism of xenobiotics, including CYP450s. Conversely, but not exclusively, many xenobiotics can inhibit the activity of CYP450s. Induction of the expression or inhibition of the activity of CYP450s can result in DDIs and toxicity. Currently, the United States (US) Food and Drug Administration does not require the investigation of the interactions of herbal supplements and CYP450s. This review provides a summary of herbal supplements that inhibit CYP450s, induce the expression of CYP450s, and/or whose toxicity is mediated by CYP450s.

Herbal Traditional Chinese Medicine and suspected liver injury: A prospective study

AIM

To analyze liver tests before and following treatment with herbal Traditional Chinese Medicine (TCM) in order to evaluate the frequency of newly detected liver injury.

METHODS

Patients with normal values of alanine aminotransferase (ALT) as a diagnostic marker for ruling out pre-existing liver disease were enrolled in a prospective study of a safety program carried out at the First German Hospital of TCM from 1994 to 2015. All patients received herbal products, and their ALT values were reassessed 1-3 d prior to discharge. To verify or exclude causality for suspected TCM herbs, the Roussel Uclaf Causality Assessment Method (RUCAM) was used.

RESULTS

This report presents for the first time liver injury data derived from a prospective, hospital-based and large-scale study of 21470 patients who had no liver disease prior to treatment with herbal TCM. Among these, ALT ranged from 1 × to < 5 × upper limit normal (ULN) in 844 patients (3.93%) and suggested mild or moderate liver adaptive abnormalities. However, 26 patients (0.12%) experienced higher ALT values of ≥ 5 × ULN (300.0 ± 172.9 U/L, mean ± SD). Causality for TCM herbs was RUCAM-based probable in 8/26 patients, possible in 16/26, and excluded in 2/26 cases. Bupleuri radix and Scutellariae radix were the two TCM herbs most commonly implicated.

CONCLUSION

In 26 (0.12%) of 21470 patients treated with herbal TCM, liver injury with ALT values of ≥ 5 × ULN was found, which normalized shortly following treatment cessation, also substantiating causality.

Biological activity and toxicity of the Chinese herb Magnolia officinalis Rehder & E. Wilson (Houpo) and its constituents

Traditional Chinese herbal drugs have been used for thousands of years in Chinese pharmacopoeia. The bark of Magnolia officinalis Rehder & E. Wilson, known under the pinyin name "Houpo", has been traditionally used in Chinese and Japanese medicines for the treatment of anxiety, asthma, depression, gastrointestinal disorders, headache, and more. Moreover, Magnolia bark extract is a major constituent of currently marketed dietary supplements and cosmetic products. Much pharmacological activity has been reported for this herb and its major compounds, notably antioxidant, anti-inflammatory, antibiotic and antispasmodic effects. However, the mechanisms underlying this have not been elucidated and only a very few clinical trials have been published. In vitro and in vivo toxicity studies have also been published and indicate some intriguing features. The present review aims to summarize the literature on M. officinalis bark composition, utilisation, pharmacology, and safety.

Screening Hepatotoxic Components in Euodia rutaecarpa by UHPLC-QTOF/MS Based on the Spectrum-Toxicity Relationship

Euodia rutaecarpa is a common traditional Chinese medicine (TCM) in clinical practice, having the ability to suppress pain and cease coughing; however, with the increasing reports showing that it is toxic, particularly hepatotoxic, the concerns raised by what cause its toxicity is growing. In the current study, an analysis method based on the spectrum effect has been employed to screen the major hepatotoxic components in Euodia rutaecarpa so that the toxic material's basis would be elucidated. A fingerprinting method of the Euodia rutaecarpa extracts (which were petroleum ether, chloroform, ethyl acetate, n-butanol, and water) using ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometer (UHPLC-QTOF/MS) has been developed. Orthogonal partial least squares (OPLS) was used to establish the spectrum-toxicity relationship with the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in mice serum as evaluation indices for liver injury. The UHPLC-MS fingerprint was established and the OPLS analytical results suggested that coniferin, 1-methyl-2-undecyl-4(1H)-quinolone, 1-methyl-2-[(6Z,9Z,12E)-pentadeca triene]-4(1H)-quinolone, evocarpine, 1-methyl-2-[(Z)-7-tridecenyl]-4(1H)-quinolone, dihydroevocarpine, and 1-methyl-2-tetradecy-4-(1H)-quinolone probably associated with the hepatotoxicity of Euodia rutaecarpa. This paper offered considerable methods and insight for the fundamental research of the toxic material basis of similar toxic TCMs.

A New Perspective on Liver Injury by Traditional Chinese Herbs Such As Polygonum multiflorum: The Geographical Area of Harvest As an Important Contributory Factor

Herbal medicine has been widely used in the treatment of various diseases; however, the adverse reactions cannot be ignored. Most previous studies have ignored the relationship between the factors of geographical areas/batches and toxicity. This study used Polygonum multiflorum (PM) as an example to analyze the relationship between the geographical areas/batches and toxicity and speculated on the hepatotoxicity-inducing components in PM based on high content screening, UHPLC-Q-TOF/MS and Progenesis QI software analysis. The results of the study show that the toxicity of PM was obviously different among the different geographical areas, and the most toxic PM was from the Sichuan province. To obtain more accurate results and to reduce the false-positive rate, two methods were used to evaluate the speculative results. It was noteworthy that emodin was not the main hepatocyte toxicity constituent of PM. The analysis methods suggested that PM toxicity may be associated with tetrahydroxystilbene-O-(galloyl)-hex and emodin-O-hex-sulfate. The toxicity of these two components requires further study.

Drug Induced Liver Injury: Can Biomarkers Assist RUCAM in Causality Assessment?

Drug induced liver injury (DILI) is a potentially serious adverse reaction in a few susceptible individuals under therapy by various drugs. Health care professionals facing DILI are confronted with a wealth of drug-unrelated liver diseases with high incidence and prevalence rates, which can confound the DILI diagnosis. Searching for alternative causes is a key element of RUCAM (Roussel Uclaf Causality Assessment Method) to assess rigorously causality in suspected DILI cases. Diagnostic biomarkers as blood tests would be a great help to clinicians, regulators, and pharmaceutical industry would be more comfortable if, in addition to RUCAM, causality of DILI can be confirmed. High specificity and sensitivity are required for any diagnostic biomarker. Although some risk factors are available to evaluate liver safety of drugs in patients, no valid diagnostic or prognostic biomarker exists currently for idiosyncratic DILI when a liver injury occurred. Identifying a biomarker in idiosyncratic DILI requires detailed knowledge of cellular and biochemical disturbances leading to apoptosis or cell necrosis and causing leakage of specific products in blood. As idiosyncratic DILI is typically a human disease and hardly reproducible in animals, pathogenetic events and resulting possible biomarkers remain largely undisclosed. Potential new diagnostic biomarkers should be evaluated in patients with DILI and RUCAM-based established causality. In conclusion, causality assessment in cases of suspected idiosyncratic DILI is still best achieved using RUCAM since specific biomarkers as diagnostic blood tests that could enhance RUCAM results are not yet available.

[Information quality and health risks in Spanish-language retail websites for Chinese herbal medicine]

OBJECTIVE

The growing use of purchase online via Internet retailers favours the access to potentially toxic natural products. It also contributes to the quick dissemination of the claims made by the retailers on efficacy and safety, these claims being not always based upon reliable information. Here, we have conducted an online search to find Spanish-language retail websites for Chinese herbal medicine and we have analysed them for the quality of product information and the potential health risks.

METHODS

i) Online search in Google España to find Spanish-language retail websites for Chinese herbal medicine in which we analysed both the claims regarding possible health benefits and adequate safe use indications ii) Identification of potentially toxic herbs in the websites iii) Quantification of Chinese herbal medicines withdrawn by the Agencia Española de Medicamentos y Productos Sanitarios (AEMPS).

RESULTS

1) Only one third of the 30 Spanish-language retail websites found which sell Chinese herbal medicine observe the law, given that the other websites include illegal Western disease claims as marketing tools, 2) Five websites provide some safety information, 3) Two websites offer potentially toxic herbs and 4) Chinese herbal medicine adulterated with sibutramine, silfenafil or their analogues make a considerable percentage of the total products withdrawn by the AEMPS.

CONCLUSION

Online health seekers should be warned about misinformation on retail websites for Chinese herbal medicine and directed to a Spanish government Web site for guidance in safely navigating the Internet for buying Chinese herbal medicine.

Ginseng for Liver Injury: Friend or Foe?

Panax sp., including Panax ginseng Meyer, Panax quiquifolius L., or Panax notoginseng (Burk.) FH Chen, have been used as functional foods or for traditional Chinese medicine for diabetes, inflammation, stress, aging, hepatic injury, and cancer. In recent decades, a number of both in vitro and in vivo experiments as well as human studies have been conducted to investigate the efficacy and safety of various types of ginseng samples and their components. Of these, the hepatoprotective and hepatotoxic effects of ginseng and their ginsenosides and polysaccharides are reviewed and summarized.

Drug-induced liver injury: Is chronic liver disease a risk factor and a clinical issue?

INTRODUCTION

Clinicians and practitioners caring for patients with chronic liver disease are often unsure whether drug therapy is a hazard that increases their patient's risk for drug-induced liver injury (DILI). Areas covered: We searched for reports of drug induced liver injury, both idiosyncratic and intrinsic, in patients with chronic liver disease including non-alcoholic and alcoholic liver disease, and cirrhosis. Reports we analyzed include statin treatment in patients with fatty liver, acetaminophen use in alcoholic fatty liver, antituberculous drugs in patients with tuberculosis and viral hepatitis, antiviral medications in hepatitis and antiretroviral medications in HIV/AIDS. The most challenging cases we found are drug therapy in patients with decompensated liver cirrhosis. Expert opinion: We identified many case reports and case series discussing a potential increased risk of DILI in patients with pre-existing liver disease. However, most of these reports were retrospective and ambiguous. With few exceptions, we conclude that drugs seem to be well tolerated by the majority of patients with pre-existing, non-cirrhotic chronic liver diseases. Special care is needed for some therapies, however, including antiviral therapy in chronic hepatitis B and C and in decompensated liver cirrhosis with impaired drug metabolism. Prospective studies are warranted to valid our conclusions.

Fatal Liver and Bone Marrow Toxicity by Combination Treatment of Dichloroacetate and Artesunate in a Glioblastoma Multiforme Patient: Case Report and Review of the Literature

A 52-year-old male patient was treated with standard radiochemotherapy with temozolomide for glioblastoma multiforme (GBM). After worsening of his clinical condition, further tumor-specific treatment was unlikely to be successful, and the patient seeked help from an alternative practitioner, who administered a combination of dichloroacetate (DCA) and artesunate (ART). A few days later, the patient showed clinical and laboratory signs of liver damage and bone marrow toxicity (leukopenia, thrombocytopenia). Despite successful restoration of laboratory parameters upon symptomatic treatment, the patient died 10 days after the infusion. DCA bears a well-documented hepatotoxic risk, while ART can be considered as safe concerning hepatotoxicity. Bone marrow toxicity can appear upon ART application as reduced reticulocyte counts and disturbed erythropoiesis. It can be assumed that the simultaneous use of both drugs caused liver injury and bone marrow toxicity. The compassionate use of DCA/ART combination therapy outside of clinical trials cannot be recommended for GBM treatment.