Evaluation of hepatotoxicity potential of a potent traditional Tibetan medicine Zuotai

Processing methods and the underlying detoxification mechanisms for toxic medicinal materials used by ethnic minorities in China: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Various toxic medicinal materials have been used by different ethnic minorities in China for thousands of years because of their extraordinary pharmacological activities. However, the improper use and complex toxicity-efficacy relationship could cause poisoning and even death. Therefore, the study of toxicity-attenuating methods and mechanisms is necessary.

AIM OF THE STUDY

This review aims to summarize commonly used toxic ethnomedicines and their processing methods as well as the underlying mechanisms to potentially reduce toxicity and even enhance or preserve efficacy. Prospective for possible future investigations is also discussed.

MATERIALS AND METHODS

Processing methods and mechanisms are investigated mainly through literature review.

RESULTS

Processing methods with heating (boiling, stir frying, and steaming, etc.) and without heating (soaking) are usually used by Chinese ethnic minorities to attenuate the toxicity of ethnomedicines. Wheat bran, vinegar, wine, and herbal decoction are commonly used processing excipients. The mechanisms of detoxification by processing can be briefly summarized into three major categories: (1) direct elimination of impurities or reduction of toxic constituents' contents of ethnomedicines by cutting, washing, soaking or frosting; (2) chemical structure transformation of toxic constituents, such as alkaloids, glycosides, toxic proteins, animal toxicants, and mineral components, during heating and/or soaking; and (3) biological synergism or antagonism effects between the chemical constituents of processing excipients and ethnomedicines in vivo, to reduce toxicity and protect target organs.

CONCLUSION

Toxic ethnomedicines have long been used in China, and detoxification by processing is the prerequisite for their safe clinical application. However, understanding on the special processing methods and detoxification mechanisms of ethnomedicines in China remains insufficient. Investigations on quality control of toxic ethnomedicines, as well as evaluation of processing methods and studies of the corresponding mechanisms should be further strengthened for safe and effective clinical application.

The Absorption, Distribution, and Excretion of 18 Elements of Tibetan Medicine Qishiwei Zhenzhu Pills in Rats with Cerebral Ischemia

The aim of this study is to determine 18 elements in Tibetan medicine Qishiwei Zhenzhu pills (QSW) and their absorption, distribution, and excretion in rats with cerebral ischemia. Microwave digestion and inductively coupled plasma mass spectrometry (ICP-MS) were used to determine 18 elements of QSW in simulated gastrointestinal (GI) juice. Rats were given QSW (66.68 mg/kg) followed by middle cerebral artery occlusion (MCAO). Sham rats received saline and were not subjected to MCAO. ICP-MS was applied to determine the content of 18 elements in hepatic venous blood, abdominal aortic blood, brain, liver, kidney, hair, urine, and feces 24 h after MCAO. In vitro results showed that the extraction rate of Mn, Cu, Sr, Pb, Au, and Hg of QSW in gastric juice (1 h) was higher than that in water, and the contents of Cu, Au, Sr, and As were higher in intestinal juice (4 h) than in water. In vivo results showed that the contents of elements in the blood were quite low, and QSW increased Ni, Cr, Sr, Co, and V in artery blood and decreased V in venous blood. Elements in the tissues were also low, and QSW increased brain Li but decreased Cr and Cd; QSW increased kidney Ag and Cs and liver Mn but decreased liver Ni. QSW increased urinary excretion of Li, Sr, Hg, Cs, and V; QSW increased Hg content in hair but decreased Ni. Stool is the main excretion pathway of the elements in QSW, with Ba, Mn, Sr, Cd, V, Cu, Cs, Li, Pb, Ag, Hg, Cr, As, and Co the highest. In summary, this study examined the distribution of 18 elements in QSW-treated MCAO rats. The accumulation of these elements in blood and tissues was extremely low, and the majority was excreted in feces within 24 h, highlighting the importance of the gut-microbiota-brain axis in QSW-mediated brain protection.

Cytochrome P450s regulates aloperine-induced pathological changes in mouse liver and kidney

Aloperine is a major active component in Sophora alopecuroides L that plays diverse pharmacological properties. Recent studies have indicated the potential effect of aloperine against hypertension and cancers. However, possible toxicity of aloperine has not been carefully studied in vivo. The aim of this study was to assess the effect of intraperitoneal aloperine injection on mouse liver and kidney tissues and to investigate the role of CYP450 genes in aloperine-induced toxicity. 72 BALB/c mice were randomly divided into four groups: vehicle control group (normal saline), low-dose group (4 mg/kg), medium-dose group (8 mg/kg), and high-dose group (16 mg/kg). 18 mice in each group were intraperitoneally injected with aloperine daily for 4 weeks, and were then kept for another 1 or 4 weeks without aloperine treatment. Serum was colleted for analysis of serum biochemical indexes including ALT, AST, BUN and CRE. The liver and kidney were collected for analysis of histopathologic changes and CYP450 expression and activity. Vacuolization of cytoplasm in liver cells, swelling in kidney tubular cells, increased levels of ALT, AST, BUN, and CRE, and alteration in the expression and activity of CYP450 were observed in the high-dose group after 4 weeks of treatment. However, all aloperine-induced damages were recovered to a certain degree after maintained without aloperine for 1 week, and fully recovered after maintained without aloperine for 4 weeks. These findings suggested that aloperine regulated the expression of CYP450, which was possibly involved in aloperine-induced reversible toxicity in mouse liver and kidney tissues.

Toxicological Risks of Renqingchangjue in Rats Evaluated by 1H NMR-Based Serum and Urine Metabolomics Analysis

Renqingchangjue (RQCJ), a kind of Traditional Tibetan Medicine, has been widely utilized to treat various gastroenteritis diseases. However, the biosafety and toxicity of RQCJ was still indefinite because of toxic components in RQCJ, which included a variety of heavy metals. Thus, this study was aimed to evaluate the toxicity and expound the toxicological mechanism of RQCJ. In this study, rats were intragastrically administered with different doses of RQCJ for 15 days, and then, the restorative observation period lasted for 15 days. Liver and kidney tissues were collected for histopathological examination, and simultaneously serum and urine samples were collected for 1H nuclear magnetic resonance (1H NMR) spectroscopy analysis and biochemical analysis combined with inductively coupled plasma mass spectrometry (ICP-MS) measurement. The 1H NMR-based metabolomics analysis revealed that the administration of RQCJ significantly altered the concentrations of 14 serum metabolites and 14 urine metabolites, which implied disturbances in energy metabolism, amino acid metabolism, intestinal flora environment, and membrane damage. Besides, the biochemical analysis of serum samples was consistent with the histopathological results, which indicated slight hepatotoxicity and nephrotoxicity. The quantification of As and Hg in urine and serum samples by ICP-MS provided more evidence about the toxicity of RQCJ. This work provided an effective method to systematically and dynamically evaluate the toxicity of RQCJ and suggested that precautions should be taken in the clinic to monitor the potential toxicity of RQCJ.

Use of Zebrafish in Drug Discovery Toxicology

Unpredicted human safety events in clinical trials for new drugs are costly in terms of human health and money. The drug discovery industry attempts to minimize those events with diligent preclinical safety testing. Current standard practices are good at preventing toxic compounds from being tested in the clinic; however, false negative preclinical toxicity results are still a reality. Continual improvement must be pursued in the preclinical realm. Higher-quality therapies can be brought forward with more information about potential toxicities and associated mechanisms. The zebrafish model is a bridge between in vitro assays and mammalian in vivo studies. This model is powerful in its breadth of application and tractability for research. In the past two decades, our understanding of disease biology and drug toxicity has grown significantly owing to thousands of studies on this tiny vertebrate. This Review summarizes challenges and strengths of the model, discusses the 3Rs value that it can deliver, highlights translatable and untranslatable biology, and brings together reports from recent studies with zebrafish focusing on new drug discovery toxicology.

Compound Phyllanthus urinaria L Inhibits HBV-Related HCC through HBx-SHH Pathway Axis Inactivation

Compound Phyllanthus urinaria L (CP) is a traditional formula widely used in clinical practice for hepatocellular carcinoma (HCC), especially HBV-related HCC. HBx, HBV X gene encoded X protein, has positive correlation with the abnormal SHH pathway in HBV-related HCC. So, we predicted that CP has the capability of anti-HBV-related HCC maybe via inactivating the HBx-Hedgehog pathway axis. HepG2-HBx cells, HBx overexpression, were treated with CP (70μg/ml and 35 μg/ml, respectively) for 48 hours and the mice which received the HepG2-HBx cells were treated with CP (625mg/kg and 300 mg/kg, respectively) for 17 days to evaluate the effect of CP on HBV-related HCC. HBx could accelerate HepG2 cells proliferation, clone formation, and migration in vitro and also could strengthen tumor growth in mice. However, CP could significantly decrease HepG2-HBx cells proliferation, clone formation, and migration in vitro and also could inhibit tumors growth in mice in a dose-dependent manner. Mechanism studies suggested that HBx upregulated the mRNA and proteins expression of Sonic hedgehog (SHH), transmembrane receptor patched (PTCH-1), smoothened (SMO), oncogene homolog transcription factors-1 (GLI-1), and oncogene homolog transcription factors-2 (GLI-2), which are compositions of the SHH pathway. CP could inhibit the mRNA and proteins expression of SHH, PTCH-1, GLI-1, and HBx. It may be one of the underlying mechanisms of CP to delay the HBV-related HCC development through the HBx-SHH pathway axis inactivation.

HgS Inhibits Oxidative Stress Caused by Hypoxia through Regulation of 5-HT Metabolism Pathway

This study aims to reveal the potential relationship between 5-HT and oxidative stress in the organism. Our in vitro experiments in RIN-14B cells showed that anoxia leads the cells to the state of oxidative stress. Administration of exogenous 5-HT exacerbated this effect, whereas the inhibition of Tph1, LP533401 alleviated the oxidative stress. Several research articles reported that Cinnabar (consists of more than 96% mercury sulfide, HgS), which is widely used in both Chinese and Indian traditional medicine prescriptions, has been involved in the regulation of 5-HT. The present research revealed that HgS relieved the level of oxidative stress of RIN-14B cells. This pharmacological activity was also observed in the prescription drug Zuotai, in which HgS accounts for 54.5%, and these effects were found to be similar to LP533401, an experimental drug to treat pulmonary hypertension. Further, our in vivo experiments revealed that the administration of cinnabar or prescription drug Zuotai in zebrafish reduced the reactive oxygen species (ROS) induced by hypoxia and cured behavioral abnormalities. Taken together, in organisms with hypoxia induced oxidative stress 5-HT levels were found to be abnormally elevated, indicating that 5-HT could regulate oxidative stress, and the decrease in the 5-HT levels, behavioral abnormalities after treatment with cinnabar and Zuotai, we may conclude that the therapeutic and pharmacologic effect of cinnabar and Zuotai may be based on the regulation of 5-HT metabolism and relief of oxidative stress. Even though they aren't toxic at the present dosage in both cell lines and zebrafish, their dose dependent toxicities are yet to be evaluated.