Oxymatrine Induces Liver Injury through JNK Signalling Pathway Mediated by TNF-αIn Vivo

Sophorae tonkinensis Radix et Rhizoma: A comprehensive review of the ethnopharmacology, phytochemistry, pharmacology, pharmacokinetics, toxicology and detoxification strategy

ETHNOPHARMACOLOGICAL RELEVANCE

Sophorae tonkinensis Radix et Rhizoma (STR), the dried root and rhizome of Sophora tonkinensis Gagnep., is commonly used in the treatment of tonsillitis and pharyngitis, throat soreness and throat obstruction, swelling and aching of gum, etc. in China or other Asian countries. STR is usually used as the core herb in traditional Chinese medicine preparations, such as "Biyanling Tablets", "Fufang Muji Granules" and "Ganyanling Injections", etc. AIM OF THE REVIEW: This review aimed to provide a comprehensive analysis of STR in terms of botany, traditional use, phytochemistry, ethnopharmacology, pharmacology, pharmacokinetics, toxicology and detoxification strategy, to provide a rational application in future research.

MATERIALS AND METHODS

The information involved in the study was gathered from a variety of electronic resources, including China National Knowledge Infrastructure (CNKI), SciFinder, Google Scholar, PubMed, Web of Science, and Chinese Masters and Doctoral Dissertations.

RESULTS

Till now, a total of 333 chemical components have been identified in STR, including 85 alkaloids, 124 flavonoids, 24 triterpenes, 27 triterpene saponins, 34 organic acids, 8 polysaccharides, etc. STR and its main active constituents have cardiovascular protection, anti-tumor activity, anti-inflammatory activity, antipyretic activity, analgesic activity, antibacterial activity, antifungal activity, antiviral activity, and hepatoprotective activity, etc. However, toxic effects of STR on the liver, nerves, heart, and gastrointestinal tract have also been observed. To mitigate these risks, STR needs attenuation before use, with the most common detoxification methods being processing and combined use with other drugs. The pharmacokinetics of STR in vivo and traditional and clinical prescriptions containing STR have been sorted out. Despite the potential therapeutic benefits of STR, further research is warranted to elucidate its hepatotoxicity, particularly in vivo, exploring aspects such as in vivo metabolism, distribution, and mechanisms.

CONCLUSION

This review serves to emphasize the therapeutic potential of STR and highlights the crucial need to address its toxicity concerns before considering clinical application. Further research is required to comprehensively investigate the toxicological properties of STR, with particular emphasis on its hepatotoxicity and neurotoxicity. Such research endeavors have the potential to standardize the rational application of STR for optimal therapeutic outcomes.

Matrine and Oxymatrine: evaluating the gene mutation potential using in silico tools and the bacterial reverse mutation assay (Ames test)

The quinolizidine alkaloids matrine and its N-oxide oxymatrine occur in plants of the genus Sophora. Recently, matrine was sporadically detected in liquorice products. Morphological similarity of the liquorice plant Glycyrrhiza glabra with Sophora species and resulting confusion during harvesting may explain this contamination, but use of matrine as pesticide has also been reported. The detection of matrine in liquorice products raised concern as some studies suggested a genotoxic activity of matrine and oxymatrine. However, these studies are fraught with uncertainties, putting the reliability and robustness into question. Another issue was that Sophora root extracts were usually tested instead of pure matrine and oxymatrine. The aim of this work was therefore to determine whether matrine and oxymatrine have potential for causing gene mutations. In a first step and to support a weight-of-evidence analysis, in silico predictions were performed to improve the database using expert and statistical systems by VEGA, Leadscope (Instem®), and Nexus (Lhasa Limited). Unfortunately, the confidence levels of the predictions were insufficient to either identify or exclude a mutagenic potential. Thus, in order to obtain reliable results, the bacterial reverse mutation assay (Ames test) was carried out in accordance with OECD Test Guideline 471. The test set included the plate incorporation and the preincubation assay. It was performed with five different bacterial strains in the presence or absence of metabolic activation. Neither matrine nor oxymatrine induced a significant increase in the number of revertants under any of the selected experimental conditions. Overall, it can be concluded that matrine and oxymatrine are unlikely to have a gene mutation potential. Any positive findings with Sophora extracts in the Ames test may be related to other components. Notably, the results also indicated a need to extend the application domain of respective (Q)SAR tools to secondary plant metabolites.

Deletion of TLR4 attenuates lipopolysaccharide-induced acute liver injury by inhibiting inflammation and apoptosis

Septic acute liver injury is one of the leading causes of fatalities in patients with sepsis. Toll-like receptor 4 (TLR4) plays a vital role in response to lipopolysaccharide (LPS) challenge, but the mechanisms underlying TLR4 function in septic injury remains unclear. In this study, we investigated the role of TLR4 in LPS-induced acute liver injury (ALI) in mice with a focus on inflammation and apoptosis. Wild-type (WT) and TLR4-knockout (TLR4-/-) mice were challenged with LPS (4 mg/kg) for 6 h. TLR4 signaling cascade markers (TLR4, MyD88, and NF-κB), inflammatory markers (TNFα, IL-1β, and IL-6), and apoptotic markers (Bax, Bcl-2, and caspase 3) were evaluated. We showed that LPS challenge markedly increased the levels of serum alanine aminotransferase (ALT)/aspartate aminotransferase (AST) and other liver pathological changes in WT mice. In addition, LPS challenge elevated the levels of liver carbonyl proteins and serum inflammatory cytokines, upregulated the expression of TLR4, MyD88, and phosphorylated NF-κB in liver tissues. Moreover, LPS challenge significantly increased hepatocyte apoptosis, caspase 3 activity, and Bax level while suppressing Bcl-2 expression in liver tissues. These pathological changes were greatly attenuated in TLR4-/- mice. Similar pathological responses were provoked in primary hepatic Kupffer cells isolated from WT and TLR4-/- mice following LPS (1 μg/mL, 6 h) challenge. In summary, these results demonstrate that silencing of TLR4 attenuates LPS-induced liver injury through inhibition of inflammation and apoptosis via TLR4/MyD88/NF-κB signaling pathway. TLR4 deletion confers hepatoprotection against ALI induced by LPS, possibly by repressing macrophage inflammation and apoptosis.

Current Overviews on COVID-19 Management Strategies

The coronavirus pandemic has hit the world lately and caused acute respiratory syndrome in humans. The causative agent of the disease was soon brought to focus by scientists as SARS-CoV-2 and later called a novel coronavirus by the general public. Due to the severity and rapid spread of the disease, WHO classifies the COVID-19 pandemic as the 6th public health emergency even after taking efforts like worldwide quarantine and restrictions. Since only symptomatic treatment is available, the best way to control the spread of the virus is by taking preventive measures. Various types of antigen/antibody detection kits and diagnostic methods are available for the diagnosis of COVID-19 patients. In recent years, various phytochemicals and repurposing drugs are showing a broad range of anti-viral activities with different modes of action have been identified. Repurposing drugs such as arbidol, hydroxychloroquine, chloroquine, lopinavir, favipiravir, remdesivir, hexamethylene amiloride, and dexamethasone, tocilizumab, interferon-β, neutralizing antibodies exhibit in vitro anti-coronaviral properties by inhibiting multiple processes in the virus life cycle. Various research groups are involved in drug trials and vaccine development. Plant-based anti-viral compounds such as baicalin, calanolides, curcumin, oxymatrine, matrine, and resveratrol exhibit different modes of action against a wide range of positive/negative sense-RNA/DNA virus, and future researches need to be conducted to ascertain their role, use in managing SARS-CoV-2. Thus, this article is an attempt to review the current understanding of COVID-19 acute respiratory disease and summarize its clinical features with their prospective control and various aspects of the therapeutic approach.

Classification, hepatotoxic mechanisms, and targets of the risk ingredients in traditional Chinese medicine-induced liver injury

Traditional Chinese medicine (TCM) has become a crucial cause of drug-induced liver injury (DILI). Differ from chemical medicines, TCM feature more complex and mostly indefinite components. This review aimed to clarify the classification, underlying mechanisms and targets of the risk components in TCM-induced liver injury to further guide the secure application of TCM. Relevant studies or articles published on the PubMed database from January 2008 to December 2019 were searched. Based on the different chemical structures of the risk ingredients in TCM, they are divided into alkaloids, glycosides, toxic proteins, terpenoids and lactones, anthraquinones, and heavy metals. According to whether drug metabolism is activated or hepatocytes are directly attacked during TCM-induced liver injury, the high-risk substances can be classified into metabolic activation, non-metabolic activation, and mixed types. Mechanisms of the hepatotoxic ingredients in TCM-induced hepatotoxicity, including cytochrome P450 (CYP450) induction, mitochondrial dysfunction, oxidative damage, apoptosis, and idiosyncratic reaction, were also summarized. The targets involved in the risk ingredient-induced hepatocellular injury mainly include metabolic enzymes, nuclear receptors, transporters, and signaling pathways. Our periodic review and summary on the risk signals of TCM-induced liver injury must be beneficial to the integrated analysis on the multi-component, multi-target, and multi-effect characteristics of TCM-induced hepatotoxicity.

Repurposing of plant alkaloids for cancer therapy: Pharmacology and toxicology

Drug repurposing (or repositioning) is an emerging concept to use old drugs for new treatment indications. Phytochemicals isolated from medicinal plants have been largely neglected in this context, although their pharmacological activities have been well investigated in the past, and they may have considerable potentials for repositioning. A grand number of plant alkaloids inhibit syngeneic or xenograft tumor growth in vivo. Molecular modes of action in cancer cells include induction of cell cycle arrest, intrinsic and extrinsic apoptosis, autophagy, inhibition of angiogenesis and glycolysis, stress and anti-inflammatory responses, regulation of immune functions, cellular differentiation, and inhibition of invasion and metastasis. Numerous underlying signaling processes are affected by plant alkaloids. Furthermore, plant alkaloids suppress carcinogenesis, indicating chemopreventive properties. Some plant alkaloids reveal toxicities such as hepato-, nephro- or genotoxicity, which disqualifies them for repositioning purposes. Others even protect from hepatotoxicity or cardiotoxicity of xenobiotics and established anticancer drugs. The present survey of the published literature clearly demonstrates that plant alkaloids have the potential for repositioning in cancer therapy. Exploitation of the chemical diversity of natural alkaloids may enrich the candidate pool of compounds for cancer chemotherapy and -prevention. Their further preclinical and clinical development should follow the same stringent rules as for any other synthetic drug as well. Prospective randomized, placebo-controlled clinical phase I and II trials should be initiated to unravel the full potential of plant alkaloids for drug repositioning.

Lactobacillus rhamnosus GG Ameliorates Liver Injury and Hypoxic Hepatitis in Rat Model of CLP-Induced Sepsis

BACKGROUND

Probiotic use to prevent gastrointestinal infections in critical care has shown great promise in recent clinical trials. Although well-documented benefits of probiotic use in intestinal disorders, the potential for probiotic treatment to ameliorate liver injury and hypoxic hepatitis following sepsis has not been well explored.

METHODS

In order to evaluate, if Lactobacillus rhamnosus GG (LGG) treatment in septic rats will protect against liver injury, this study used 20-22-week-old Sprague-Dawley rats which were subjected to cecal ligation and puncture to establish sepsis model and examine mRNA and protein levels of IL-1β, NLRP3, IL-6, TNF-a, VEGF, MCP1, NF-kB and HIF-1α in the liver via real-time PCR, Elisa and Western blot.

RESULTS

This study showed that LGG treatment significantly ameliorated liver injury following experimental infection and sepsis. Liver mRNA and protein levels of IL-1β, NLRP3, IL-6, TNF-a, VEGF, MCP1, NF-kB and HIF-1α were significantly reduced in rats receiving LGG.

CONCLUSIONS

Thus, our study demonstrated that LGG treatment can reduce liver injury following experimental infection and sepsis and is associated with improved hypoxic hepatitis. Probiotic therapy may be a promising intervention to ameliorate clinical liver injury and hypoxic hepatitis following systemic infection and sepsis.

Oxymatrine and its metabolite matrine contribute to the hepatotoxicity induced by radix Sophorae tonkinensis in mice

Previous studies by our group demonstrated that radix Sophorae tonkinensis could induce hepatotoxicity. However, it remains unclear which components of this herb may be responsible for its hepatotoxicity. The present study aimed to investigate the hepatic toxicity of treatment with matrine (MT) and oxymatrine (OMT) alone or simultaneously. Furthermore, the current study aimed to identify whether the hepatotoxicity induced by OMT is actually the toxic characterization of its metabolite MT. Hepatotoxicity was evaluated by biochemical and histopathological approaches in subchronic toxicity in mice, as well as via evaluation of cytotoxicity and enzyme leakage in AML12 liver cells. The results indicated that treatment of mice with OMT and MT individually or simultaneously resulted in centrilobular hypertrophy in the liver at doses equivalent to that contained in radix S. tonkinensis at a hepatotoxic dose, suggesting that MT and OMT are likely hepatotoxic components of this herb. OMT-induced hepatotoxicity may be primarily exerted via its metabolite MT in mice. Furthermore, OMT combined with MT was observed to be more toxic compared with OMT or MT alone. These results extend our understanding of the hepatotoxicity of radix S. tonkinensis and its active ingredients.

Molecular Mechanisms Involved in Oxidative Stress-Associated Liver Injury Induced by Chinese Herbal Medicine: An Experimental Evidence-Based Literature Review and Network Pharmacology Study

Oxidative stress, defined as a disequilibrium between pro-oxidants and antioxidants, can result in histopathological lesions with a broad spectrum, ranging from asymptomatic hepatitis to hepatocellular carcinoma in an orchestrated manner. Although cells are equipped with sophisticated strategies to maintain the redox biology under normal conditions, the abundance of redox-sensitive xenobiotics, such as medicinal ingredients originated from herbs or animals, can dramatically invoke oxidative stress. Growing evidence has documented that the hepatotoxicity can be triggered by traditional Chinese medicine (TCM) during treating various diseases. Meanwhile, TCM-dependent hepatic disorder represents a strong correlation with oxidative stress, especially the persistent accumulation of intracellular reactive oxygen species. Of note, since TCM-derived compounds with their modulated targets are greatly diversified among themselves, it is complicated to elaborate the potential pathological mechanism. In this regard, data mining approaches, including network pharmacology and bioinformatics enrichment analysis have been utilized to scientifically disclose the underlying pathogenesis. Herein, top 10 principal TCM-modulated targets for oxidative hepatotoxicity including superoxide dismutases (SOD), malondialdehyde (MDA), glutathione (GSH), reactive oxygen species (ROS), glutathione peroxidase (GPx), Bax, caspase-3, Bcl-2, nuclear factor (erythroid-derived 2)-like 2 (Nrf2), and nitric oxide (NO) have been identified. Furthermore, hepatic metabolic dysregulation may be the predominant pathological mechanism involved in TCM-induced hepatotoxic impairment.

Oxymatrine Causes Hepatotoxicity by Promoting the Phosphorylation of JNK and Induction of Endoplasmic Reticulum Stress Mediated by ROS in LO2 Cells

Oxymatrine (OMT) often used in treatment for chronic hepatitis B virus infection in clinic. However, OMT-induced liver injury has been reported. In this study, we aim to investigate the possible mechanism of OMT-induced hepatotoxicity in human normal liver cells (L02). Exposed cells to OMT, the cell viability was decreased and apoptosis rate increased, the intracellular markers of oxidative stress were changed. Simultaneously, OMT altered apoptotic related proteins levels, including Bcl-2, Bax and pro-caspase-8/-9/-3. In addition, OMT enhanced the protein levels of endoplasmic reticulum (ER) stress makers (GRP78/Bip, CHOP, and cleaved-Caspase-4) and phosphorylation of c-Jun N-terminal kinase (p-JNK), as well as the mRNA levels of GRP78/Bip, CHOP, caspase-4, and ER stress sensors (IREI, ATF6, and PERK). Pre-treatment with Z-VAD-fmk, JNK inhibitor SP600125 and N-acetyl-l-cysteine (NAC), a ROS scavenger, partly improved the survival rates and restored OMT-induced cellular damage, and reduced caspase-3 cleavage. SP600125 or NAC reduced OMT-induced p-JNK and NAC significantly lowered caspase-4. Furthermore, 4-PBA, the ER stress inhibitor, weakened inhibitory effect of OMT on cells, on the contrary, TM worsen. 4-PBA also reduced the levels of p-JNK and cleaved-caspase-3 proteins. Therefore, OMT-induced injury in L02 cells was related to ROS mediated p-JNK and ER stress induction. Antioxidant, by inhibition of p-JNK or ER stress, may be a feasible method to alleviate OMT-induced liver injury.

Oxymatrine attenuates lipopolysaccharide-induced acute lung injury by activating the epithelial sodium channel and suppressing the JNK signaling pathway

The epithelial sodium channel (ENaC) and mitogen-activated protein kinase (MAPK) pathway have been reported to be associated with the progression of acute lung injury (ALI). Oxymatrine (OMT) alone or combined with other drugs can ameliorate paraquat- or oleic acid-induced lung injury. However, the effect of OMT on lipopolysaccharide (LPS)-induced ALI remains unknown. The aim of the present study was to evaluate whether OMT can attenuate LPS-induced ALI through regulation of the ENaC and MAPK pathway using an ALI mouse model. Histological assessment of the lung and inflammatory cell counts in bronchoalveolar lavage fluid (BALF) were performed by H&E and Wright-Giemsa staining. The lung wet/dry (W/D) weight ratio and the levels of tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), ENaC subunits, and the MAPK pathway members were determined. Isolated type II rat alveolar epithelial cells were incubated with OMT 30 min before LPS stimulation to investigate the activation of ENaC and the MAPK pathway. The results showed that OMT remarkably alleviated histopathologic changes in lung and pulmonary edema, reduced inflammatory cell counts in BALF, and decreased TNF-α and CRP levels in a dose-dependent manner. OMT significantly increased the three subunits of ENaC proteins in vivo and in vitro, while it decreased p-ERK/ERK, p-p38/p38, and p-JNK/JNK ratios in vivo. However, only the JNK pathway was markedly inhibited in vitro following pretreatment with OMT. Collectively, the results suggested that OMT might alleviate LPS-induced ALI by elevating ENaC proteins and inhibiting the JNK signaling pathway.

Hepatotoxicity evaluation of traditional Chinese medicines using a computational molecular model

BACKGROUND

Liver injury caused by traditional Chinese medicines (TCMs) is reported from many countries around the world. TCM hepatotoxicity has attracted worldwide concerns.

OBJECTIVE

This study aims to develop a more applicable and optimal tool to evaluate TCM hepatotoxicity.

METHODS

A quantitative structure-activity relationship (QSAR) analysis was performed based on published data and U.S. Food and Drug Administration's Liver Toxicity Knowledge Base (LTKB).

RESULTS

Eleven herbal ingredients with proven liver toxicity in the literature were added into the dataset besides chemicals from LTKB. The finally generated QSAR model yielded a sensitivity of 83.8%, a specificity of 70.1%, and an accuracy of 80.2%. Among the externally tested 20 ingredients from TCMs, 14 hepatotoxic ingredients were all accurately identified by the QSAR model derived from the dataset containing natural hepatotoxins.

CONCLUSIONS

Adding natural hepatotoxins into the dataset makes the QSAR model more applicable for TCM hepatotoxicity assessment, which provides a right direction in the methodology study for TCM safety evaluation. The generated QSAR model has the practical value to prioritize the hepatotoxicity risk of TCM compounds. Furthermore, an open-access international specialized database on TCM hepatotoxicity should be quickly established.