Recent advances in Scutellariae radix: A comprehensive review on ethnobotanical uses, processing, phytochemistry, pharmacological effects, quality control and influence factors of biosynthesis

Background

Scutellariae radix (SR) is the dried root of Scutellaria baicalensis Georgi. It has a long history of ethnic medicinal use, traditionally recognized for its efficacy in clearing heat， drying dampness, eliminating fire， removing toxins , stopping bleeding and tranquilizing fetus to prevent miscarriage. Clinically, it is used to treat cold, fever, migraine, hand-foot-and-mouth diseases, liver cancer and inflammatory diseases.

Purpose

The review aims to provide a comprehensive reference on the ethnobotanical uses, processing, phytochemistry, pharmacological effect, quality control and influence factors of biosynthesis for a deeper understanding of SR.

Results and conclusion

A total of 210 isolated components have been reported in the literature, including flavonoids and their glycosides, phenylpropanoids, phenylethanoid glycosides, phenolic acids, volatile components, polysaccharides and others. The extract of SR and its main flavonoids such as baicalin, baicalein, wogonin, wogonoside, and scutellarin showed antioxidant, anti-inflammatory, anti-tumor, antiviral, hepatoprotective, and neuroprotective effects. However, further studies are required to elucidate its mechanisms of action and clinical applications. The pharmacodynamic evaluation based on traditional efficacy should be conducted. Although various analytical methods have been established for the quality control of SR, there are gaps in the research regarding efficacy-related quality markers and the development of quality control standards for its processed products. The regulatory mechanisms of flavonoids biosynthesis remain to be explored while the influence of environmental and transcription factors on the biosynthesis have been studied. In conclusion, SR is a promising herbal medicine with significant potential for future development.

Glycyrrhizic acid restores the downregulated hepatic ACE2 signaling in the attenuation of mouse steatohepatitis

Glycyrrhizic acid (GA), one of the major active components derived from licorice root, exerts liver-protecting activity. Its molecular mechanisms of action, however, remain not completely understood. The angiotensin (Ang) converting enzyme (ACE) 2/Ang-(1-7)/Mas axis, regulated by ACE2 through converting Ang II into Ang-(1-7) to activate Mas receptor, counteracts the pro-inflammatory and pro-steatotic effects of the ACE/Ang II/Ang II receptor type 1 (AT1) axis. Here, it was found that pretreatment with GA suppressed LPS/D-galactosamine-induced serum hyperactivities of alanine aminotransferase and aspartate aminotransferase, hepatomegaly, pathological changes, and over-accumulation of triglycerides and fatty droplets in the liver of mice. GA also diminished LPS/free fatty acid-induced inflammation and steatosis in cultured hepatocytes. Mechanistically, GA restored hepatic protein hypoexpression of ACE2 and Mas receptor, and the decrease in hepatic Ang-(1-7) content. Hepatic overexpression of angiotensin II and AT1 was also suppressed. However, GA did not alter hepatic protein expression of renin and ACE. In addition, GA inhibited hepatic protein over-phosphorylation of the p38 mitogen-activated protein kinase, c-Jun N-terminal kinase, extracellular signal-regulated kinase, and nuclear factor κB at Ser536. Hepatic overexpression of tumor necrosis factor α, interleukin 6, interleukin 1β, sterol regulatory element-binding protein 1c, and fatty acid synthase was also inhibited. GA-elicited recovery of ACE2 and Mas protein hypoexpression was further confirmed in the hepatocyte. Thus, the present results demonstrate that GA restores the downregulated hepatic ACE2-mediated anti-inflammatory and anti-steatotic signaling in the amelioration of steatohepatitis. We suggest that GA may protect the liver from injury by regulating the hepatic ACE2-mediated signaling.

Unveiling the therapeutic promise of natural products in alleviating drug-induced liver injury: Present advancements and future prospects

Drug-induced liver injury (DILI) refers to adverse reactions to small chemical compounds, biological agents, and medical products. These reactions can manifest as acute or chronic damage to the liver. From 1997 to 2016, eight drugs, including troglitazone, nefazodone, and lumiracoxib, were removed from the market due to their liver-damaging effects, which can cause diseases. We aimed to review the recent research on natural products and their bioactive components as hepatoprotective agents in mitigating DILI. Recent articles were fetched via searching the PubMed, PMC, Google Scholar, and Web of Science electronic databases from 2010 to January 2023 using relevant keywords such as "natural products," "acetaminophen," "antibiotics," "paracetamol," "DILI," "hepatoprotective," "drug-induced liver injury," "liver failure," and "mitigation." The studies reveal that the antituberculosis drug (acetaminophen) is the most frequent cause of DILI, and natural products have been largely explored in alleviating acetaminophen-induced liver injury. They exert significant hepatoprotective effects by preventing mitochondrial dysfunction and inflammation, inhibiting oxidative/nitrative stress, and macromolecular damage. Due to the bioavailability and dietary nature, using natural products alone or as an adjuvant with existing drugs is promising. To advance DILI management, it is crucial to conduct well-designed randomized clinical trials to evaluate natural products' efficacy and develop new molecules clinically. However, natural products are a promising solution for remedying drug-induced hepatotoxicity and lowering the risk of DILI.

NLRP3 inflammasome in hepatic diseases: A pharmacological target

The NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome pathway is mainly responsible for the activation and release of a cascade of proinflammatory mediators that contribute to the development of hepatic diseases. During alcoholic liver disease development, the NLRP3 inflammasome pathway contributes to the maturation of caspase-1, interleukin (IL)-1β, and IL-18, which induce a robust inflammatory response, leading to fibrosis by inducing profibrogenic hepatic stellate cell (HSC) activation. Substantial evidence demonstrates that nonalcoholic fatty liver disease (NAFLD) progresses to nonalcoholic steatohepatitis (NASH) via NLRP3 inflammasome activation, ultimately leading to fibrosis and hepatocellular carcinoma (HCC). Activation of the NLRP3 inflammasome in NASH can be attributed to several factors, such as reactive oxygen species (ROS), gut dysbiosis, leaky gut, which allow triggers such as cardiolipin, cholesterol crystals, endoplasmic reticulum stress, and uric acid to reach the liver. Because inflammation triggers HSC activation, the NLRP3 inflammasome pathway performs a central function in fibrogenesis regardless of the etiology. Chronic hepatic activation of the NLRP3 inflammasome can ultimately lead to HCC; however, inflammation also plays a role in decreasing tumor growth. Some data indicate that NLRP3 inflammasome activation plays an important role in autoimmune hepatitis, but the evidence is scarce. Most researchers have reported that NLRP3 inflammasome activation is essential in liver injury induced by a variety of drugs and hepatotropic virus infection; however, few reports indicate that this pathway can play a beneficial role by inducing liver regeneration. Modulation of the NLRP3 inflammasome appears to be a suitable strategy to treat liver diseases.

ERK/NF-kB/COX-2 Signaling Pathway Plays a Key Role in Curcumin Protection against Acetaminophen-Induced Liver Injury

Recent experimental studies have highlighted the beneficial effects of curcumin on liver injury induced by acetaminophen (APAP). However, the specific molecular mechanisms underlying curcumin's hepatoprotective effects against APAP-induced liver injury remain to be fully elucidated. This study aimed to investigate the therapeutic effect of curcumin on APAP-induced liver injury using a mouse model. In the experiment, mice were subjected to an intraperitoneal hepatotoxic dose of APAP (300 mg/kg) to induce hepatotoxicity. After 30 min of APAP administration, the mice were treated with different concentrations of curcumin (0, 10, 25, or 50 mg/kg). After 16 h, mice with hepatotoxicity showed elevated levels of serum alanine transaminase (ALT), aspartate transaminase (AST), hepatic myeloperoxidase (MPO), TNF-α, and IL-6, and decreased levels of glutathione (GSH). Moreover, there was an increased infiltration of neutrophils and macrophages following intraperitoneal injection of APAP. However, curcumin-treated mice displayed a pronounced reduction in serum ALT, AST, hepatic MPO, TNF-α, and IL-6 levels, coupled with a notable elevation in GSH levels compared to the APAP-treated hepatotoxic mice. Moreover, curcumin treatment led to reduced infiltration of neutrophils and macrophages. Additionally, curcumin inhibited the phosphorylation of ERK and NF-kB proteins while reducing the expression of cyclooxygenase-2 (COX-2). These findings highlight the hepatoprotective potential of curcumin against APAP-induced liver injury through the suppression of the ERK, NF-kB, and COX-2 signaling pathways.

Pathophysiological consequences and treatment strategy of obstructive jaundice

Obstructive jaundice (OJ) is a common problem in daily clinical practice. However, completely understanding the pathophysiological changes in OJ remains a challenge for planning current and future management. The effects of OJ are widespread, affecting the biliary tree, hepatic cells, liver function, and causing systemic complications. The lack of bile in the intestine, destruction of the intestinal mucosal barrier, and increased absorption of endotoxins can lead to endotoxemia, production of proinflammatory cytokines, and induce systemic inflammatory response syndrome, ultimately leading to multiple organ dysfunction syndrome. Proper management of OJ includes adequate water supply and electrolyte replacement, nutritional support, preventive antibiotics, pain relief, and itching relief. The surgical treatment of OJ depends on the cause, location, and severity of the obstruction. Biliary drainage, surgery, and endoscopic intervention are potential treatment options depending on the patient's condition. In addition to modern medical treatments, Traditional Chinese medicine may offer therapeutic benefits for OJ. A comprehensive search was conducted on PubMed for relevant articles published up to August 1970. This review discusses in detail the pathophysiological changes associated with OJ and presents effective strategies for managing the condition.

Targeting the Interplay of Autophagy and ROS for Cancer Therapy: An Updated Overview on Phytochemicals

Autophagy is an evolutionarily conserved self-degradation system that recycles cellular components and damaged organelles, which is critical for the maintenance of cellular homeostasis. Intracellular reactive oxygen species (ROS) are short-lived molecules containing unpaired electrons that are formed by the partial reduction of molecular oxygen. It is widely known that autophagy and ROS can regulate each other to influence the progression of cancer. Recently, due to the wide potent anti-cancer effects with minimal side effects, phytochemicals, especially those that can modulate ROS and autophagy, have attracted great interest of researchers. In this review, we afford an overview of the complex regulatory relationship between autophagy and ROS in cancer, with an emphasis on phytochemicals that regulate ROS and autophagy for cancer therapy. We also discuss the effects of ROS/autophagy inhibitors on the anti-cancer effects of phytochemicals, and the challenges associated with harnessing the regulation potential on ROS and autophagy of phytochemicals for cancer therapy.

Protective activity of purpurin against d-galactosamine and lipopolysaccharide-induced hepatorenal injury by upregulation of heme oxygenase-1 in the RBC degradation cycle

Acute liver failure, associated with oxidative stress and sustained inflammation is the major clinical manifestation of liver diseases with a high mortality rate due to limited therapeutic options. Purpurin is a bioactive compound of Rubia cordifolia that has been used in textile staining, as a food additive, and as a treatment of multiple chronic and metabolic diseases associated with inflammation and oxidative stress. The present work aimed to investigate the protective efficacy of purpurin against hepatorenal damage. Thirty-six female albino rats were equally assigned into six groups. Purpurin was administered orally once a day for 6 days at doses of 05, 10, and 20 mg/kg, respectively. Intraperitoneal injection of lipopolysaccharide (50 μg/kg) was administered to the animals on 6th day evening, 1 h after d-galactosamine (300 mg/kg) administration to induce hepatorenal injury. The results revealed that purpurin alleviated alterations in serological and hematological parameters as well as restored histoarchitectural and cellular integrity of the liver and kidney. Purpurin restored superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase, and glutathione content in hepatorenal tissues. Accompanied by the diminution of increased bilirubin and biliverdin, purpurin also diminished total cholesterol, triglyceride, and lipid peroxidation in hepatorenal tissues. Purpurin markedly attenuated the elevation of CYP2E1, restored glutathione-S-transferase, and prevented DNA damage in hepatorenal tissues. Purpurin reduced iron overload by reducing heme depletion and recycling of ferritin and hemosiderin. It also reinforced biliverdin reductase, heme oxygenase-1 to employ hepatorenal protection by regulating antioxidant enzymes and other pathways that produced NADPH. Thus, it may be concluded that purpurin has protective potential against acute hepatorenal injury.

Polyphenols in Metabolic Diseases

Polyphenols (PPs) are a large group of phytochemicals containing phenolic rings with two or more hydroxyl groups. They possess powerful antioxidant properties, multiple therapeutic effects, and possible health benefits in vivo and in vitro, as well as reported clinical studies. Considering their free-radical scavenging and anti-inflammatory properties, these substances can be used to treat different kinds of conditions associated with metabolic disorders. Many symptoms of metabolic syndrome (MtS), including obesity, dyslipidemia, atherosclerosis, elevated blood sugar, accelerating aging, liver intoxication, hypertension, as well as cancer and neurodegenerative disorders, are substantially relieved by dietary PPs. The present study explores the bioprotective properties and associated underlying mechanisms of PPs. A detailed understanding of these natural compounds will open up new opportunities for producing unique natural PP-rich dietary and medicinal plans, ultimately affirming their health benefits.

Role of baicalin as a potential therapeutic agent in hepatobiliary and gastrointestinal disorders: A review

Baicalin is a natural bioactive compound derived from Scutellaria baicalensis, which is extensively used in traditional Chinese medicine. A literature survey demonstrated the broad spectrum of health benefits of baicalin such as antioxidant, anticancer, anti-inflammatory, antimicrobial, cardio-protective, hepatoprotective, renal protective, and neuroprotective properties. Baicalin is hydrolyzed to its metabolite baicalein by the action of gut microbiota, which is further reconverted to baicalin via phase 2 metabolism in the liver. Many studies have suggested that baicalin exhibits therapeutic potential against several types of hepatic disorders including hepatic fibrosis, xenobiotic-induced liver injury, fatty liver disease, viral hepatitis, cholestasis, ulcerative colitis, hepatocellular and colorectal cancer. During in vitro and in vivo examinations, it has been observed that baicalin showed a protective role against liver and gut-associated abnormalities by modifying several signaling pathways such as nuclear factor-kappa B, transforming growth factor beta 1/SMAD3, sirtuin 1, p38/mitogen-activated protein kinase/Janus kinase, and calcium/calmodulin-dependent protein kinase kinaseβ/adenosine monophosphate-activated protein kinase/acetyl-coenzyme A carboxylase pathways. Furthermore, baicalin also regulates the expression of fibrotic genes such as smooth muscle actin, connective tissue growth factor, β-catenin, and inflammatory cytokines such as interferon gamma, interleukin-6 (IL-6), tumor necrosis factor-alpha, and IL-1β, and attenuates the production of apoptotic proteins such as caspase-3, caspase-9 and B-cell lymphoma 2. However, due to its low solubility and poor bioavailability, widespread therapeutic applications of baicalin still remain a challenge. This review summarized the hepatic and gastrointestinal protective attributes of baicalin with an emphasis on the molecular mechanisms that regulate the interaction of baicalin with the gut microbiota.

Scutellaria baicalensis and its constituents baicalin and baicalein as antidotes or protective agents against chemical toxicities: a comprehensive review

Scutellaria baicalensis (SB), also known as the Chinese skullcap, has a long history of being used in Chinese medicine to treat a variety of conditions ranging from microbial infections to metabolic syndrome and malignancies. Numerous studies have reported that treatment with total SB extract or two main flavonoids found in its root and leaves, baicalin (BA) and baicalein (BE), can prevent or alleviate the detrimental toxic effects of exposure to various chemical compounds. It has been shown that BA and BE are generally behind the protective effects of SB against toxicants. This paper aimed to review the protective and therapeutic effects of SB and its main components BA and BE against chemical compounds that can cause intoxication after acute or chronic exposure and seriously affect different vital organs including the brain, heart, liver, and kidneys. In this review paper, we had a look into a total of 221 in vitro and in vivo studies from 1995 to 2021 from the scientific databases PubMed, Scopus, and Web of Science which reported protective or therapeutic effects of BA, BE, or SB against drugs and chemicals that one might be exposed to on a professional or accidental basis and compounds that are primarily used to simulate disease models. In conclusion, the protective effects of SB and its flavonoids can be mainly attributed to increase in antioxidants enzymes, inhibition of lipid peroxidation, reduction of inflammatory cytokines, and suppression of apoptosis pathway.

Molecular pathogenesis of acetaminophen-induced liver injury and its treatment options

Acetaminophen, also known as N-acetyl-p-aminophenol (APAP), is commonly used as an antipyretic and analgesic agent. APAP overdose can induce hepatic toxicity, known as acetaminophen-induced liver injury (AILI). However, therapeutic doses of APAP can also induce AILI in patients with excessive alcohol intake or who are fasting. Hence, there is a need to understand the potential pathological mechanisms underlying AILI. In this review, we summarize three main mechanisms involved in the pathogenesis of AILI: hepatocyte necrosis, sterile inflammation, and hepatocyte regeneration. The relevant factors are elucidated and discussed. For instance, N-acetyl-p-benzoquinone imine (NAPQI) protein adducts trigger mitochondrial oxidative/nitrosative stress during hepatocyte necrosis, danger-associated molecular patterns (DAMPs) are released to elicit sterile inflammation, and certain growth factors contribute to liver regeneration. Finally, we describe the current potential treatment options for AILI patients and promising novel strategies available to researchers and pharmacists. This review provides a clearer understanding of AILI-related mechanisms to guide drug screening and selection for the clinical treatment of AILI patients in the future.

Mechanism of drug-induced liver injury and hepatoprotective effects of natural drugs

Drug-induced liver injury (DILI) is a common adverse drug reaction (ADR) and a serious threat to health that affects disease treatments. At present, no targeted clinical drugs are available for DILI. Traditional natural medicines have been widely used as health products. Some natural medicines exert specific hepatoprotective effects, with few side effects and significant clinical efficacy. Thus, natural medicines may be a promising direction for DILI treatment. In this review, we summarize the current knowledge, common drugs and mechanisms of DILI, as well as the clinical trials of natural drugs and their bioactive components in anticipation of the future development of potential hepatoprotective drugs.

The Potential Application of Chinese Medicine in Liver Diseases: A New Opportunity

Liver diseases have been a common challenge for people all over the world, which threatens the quality of life and safety of hundreds of millions of patients. China is a major country with liver diseases. Metabolic associated fatty liver disease, hepatitis B virus and alcoholic liver disease are the three most common liver diseases in our country, and the number of patients with liver cancer is increasing. Therefore, finding effective drugs to treat liver disease has become an urgent task. Chinese medicine (CM) has the advantages of low cost, high safety, and various biological activities, which is an important factor for the prevention and treatment of liver diseases. This review systematically summarizes the potential of CM in the treatment of liver diseases, showing that CM can alleviate liver diseases by regulating lipid metabolism, bile acid metabolism, immune function, and gut microbiota, as well as exerting anti-liver injury, anti-oxidation, and anti-hepatitis virus effects. Among them, Keap1/Nrf2, TGF-β/SMADS, p38 MAPK, NF-κB/IκBα, NF-κB-NLRP3, PI3K/Akt, TLR4-MyD88-NF-κB and IL-6/STAT3 signaling pathways are mainly involved. In conclusion, CM is very likely to be a potential candidate for liver disease treatment based on modern phytochemistry, pharmacology, and genomeproteomics, which needs more clinical trials to further clarify its importance in the treatment of liver diseases.

The dual role of immune response in acetaminophen hepatotoxicity: Implication for immune pharmacological targets

Acetaminophen (APAP), one of the most widely used antipyretic and analgesic drugs, principally contributes to drug-induced liver injury when taken at a high dose. APAP-induced liver injury (AILI) results in extensive necrosis of hepatocytes along with the occurrence of multiple intracellular events such as metabolic activation, cell injury, and signaling pathway activation. However, the specific role of the immune response in AILI remains controversial for its complicated regulatory mechanisms. A variety of inflammasomes, immune cells, inflammatory mediators, and signaling transduction pathways are activated in AILI. These immune components play antagonistic roles in aggravating the liver injury or promoting regeneration. Recent experimental studies indicated that natural products showed remarkable therapeutic effects against APAP hepatotoxicity due to their favorable efficacy. Therefore, this study aimed to review the present understanding of the immune response in AILI and attempted to establish ties among a series of inflammatory cascade reactions. Also, the immune molecular mechanisms of natural products in the treatment of AILI were extensively reviewed, thus providing a fundamental basis for exploring the potential pharmacological targets associated with immune interventions.

Citrus peel derived' Poly-Methoxylated Flavones (PMF)

The prevalence of obesity has increased substantially over the last several decades and several environmental factors have accelerated this trend. Poly-methoxy flavones (PMFs) exist abundantly in the peels of citrus, and their biological activities have been broadly examined in recent years. Several studies have examined the effects of PMFs on obesity and its-related diseases. This systematic review conducted to focus on the effect of PMFs on obesity and its related conditions management. The PubMed, Google Scholar, Scopus, and Science Direct databases were searched for relevant studies published before November 2020. Out of 1,615 records screened, 16 studies met the study criteria. The range of dosage of PMFs was varied from 10 to 200 mg/kg (5-26 weeks) and 1-100 μmol (2h-8 days) across selected animal and in vitro studies, respectively. The literature reviewed shows that PMFs modulate several biological processes associated with obesity such as lipid and glucose metabolism, inflammation, energy balance, and oxidative stress by different mechanisms. All of the animal studies showed significant positive effects of PMFs on obesity by reducing body weight (e.g. reduced weight gain by 21.04%), insulin resistance, energy expenditure, inhibiting lipogenesis and reduced blood lipids (e.g. reduced total cholesterol by 23.10%, TG by 44.35% and LDL by 34.41%). The results of the reviewed in vitro studies have revealed that treatment with PMFs significantly inhibits lipid accumulation in adipocytes (e.g. reduced lipid accumulation by 55-60%) and 3T3-L1 pre-adipocyte differentiation as well by decreasing the expression of PPARγ and C/EBPα and also reduces the number and size of fat cells and reduced TG content in adipocytes by 45.67% and 23.10% and 16.08% for nobiletin, tangeretin and hesperetin, respectively. Although current evidence supports the use of PMFs as a complementary treatment in obesity, future research is needed to validate this promising treatment modality.

TLR4-NLRP3-GSDMD-Mediated Pyroptosis Plays an Important Role in Aggravated Liver Injury of CD38-/- Sepsis Mice

Clinically, severe bacterial infection can cause septicemia and multiple organ dysfunction syndrome, especially liver injury. CD38 is closely related to many inflammatory pathways, but its role in liver injury caused by bacterial infection remains unclear. The purpose of this study is to discuss the specific role of CD38 in bacterial liver injury. Eight-week-old male C57BL/6 mice (WT, CD38^−/− and CD38^−/−TLR4^mut) were used and stimulated with Escherichia coli (ATCC25922) or PBS, intraperitoneally. After 3 hours of bacterial stimulation, serum was collected to detect ALT and AST concentration, and liver tissue was harvested for hematoxylin and eosin staining and bacterial culture. The mRNA expressions of TLR4, NLRP3, IL-1β, IL-18, and GSDMD were quantitatively determined by RT-qPCR. The expressions of TLR4, MyD88, TRIF, NF-κB p65, NLRP3, GSDMD, and cytokines were detected by Western blot. The expression and localization of ERK1/2 were detected by immunohistochemistry and Western blot. The results showed that bacterial stimulation could upregulate the expression of inflammatory cytokines, leading to hepatic dysfunction. Moreover, bacterial stimulation of CD38-deficient mice can aggravate the inflammatory response, the expressions of TLR4, NF-κB, and ERK1/2 were significantly increased, and the biomarkers related to pyroptosis also manifested more obvious pyroptosis. However, TLR4 mutation significantly alleviated inflammation and pyroptosis in the liver caused by bacteria, on the basis of CD38 deficiency. Overall, CD38 knockout exacerbates bacteria-induced liver damage through TLR4-NLRP3-GSDMD-mediated pyroptosis.

Pharmacological properties of baicalin on liver diseases: a narrative review

Baicalin is the main active component of Scutellaria baicalensis, widely used in traditional Chinese medicine thanks to its various pharmacological effects, such as anti-tumor, anti-inflammatory, and antibacterial properties, as well as cardiovascular, hepatic, and renal protective effect. Recently, the protective effects of baicalin on liver disease have received much more attention. Several studies showed that baicalin protects against several types of liver diseases including viral hepatitis, fatty liver disease, xenobiotic induced liver injury, cholestatic liver injury, and hepatocellular carcinoma, with a variety of pharmacological mechanisms. A comprehensive understanding of the mechanism of baicalin can provide a valuable reference for its clinical use, but up to now, no narrative review is available that summarizes the pharmacological effects of baicalin to clarify its potential use in the treatment of liver diseases. Therefore, this review summarizes the progress of baicalin research and the underlying mechanism in the treatment of various liver diseases, to promote further research and its clinical application.

Baicalin and the liver-gut system: Pharmacological bases explaining its therapeutic effects

With the development of high-throughput screening and bioinformatics technology, natural products with a range of pharmacological targets in multiple diseases have become important sources of new drug discovery. These compounds are derived from various plants, including the dried root of Scutellaria baicalensis Georgi, which is often used as a traditional Chinese herb named Huangqin, a popular medication used for thousands of years in China. Many studies have shown that baicalin, an extract from Scutellaria baicalensis Georgi, exerts various protective effects on liver and gut diseases. Baicalin plays a therapeutic role mainly by mediating downstream apoptosis and immune response pathways induced by upstream oxidative stress and inflammation. During oxidative stress regulation, PI3K/Akt/NRF2, Keap-1, NF-κB and HO-1 are key factors associated with the healing effects of baicalin on NAFLD/NASH, ulcerative colitis and cholestasis. In the inflammatory response, IL-6, IL-1β, TNF-α, MIP-2 and MIP-1α are involved in the alleviation of NAFLD/NASH, cholestasis and liver fibrosis by baicalin, as are TGF-β1/Smads, STAT3 and NF-κB. Regarding the apoptosis pathway, Bax, Bcl-2, Caspase-3 and Caspase-9 are key factors related to the suppression of hepatocellular carcinoma and attenuation of liver injury and colorectal cancer. In addition to immune regulation, PD-1/PDL-1 and TLR4-NF-κB are correlated with the alleviation of hepatocellular carcinoma, ulcerative colitis and colorectal cancer by baicalin. Moreover, baicalin regulates intestinal flora by promoting the production of SCFAs. Furthermore, BA is involved in the interactions of the liver-gut axis by regulating TGR5, FXR, bile acids and the microbiota. In general, a comprehensive analysis of this natural compound was conducted to determine the mechanism by which it regulates bile acid metabolism, the intestinal flora and related signaling pathways, providing new insights into the pharmacological effects of baicalin. The mechanism linking the liver and gut systems needs to be elucidated to draw attention to its great clinical importance.

Baicalin promotes liver regeneration after acetaminophen-induced liver injury by inducing NLRP3 inflammasome activation

Liver regeneration has become a new hotspot in the study of drug-induced liver injury (DILI). Baicalin has already been reported to alleviate acetaminophen (APAP)-induced acute liver injury in our previous study. This study aims to observe whether baicalin also promotes liver regeneration after APAP-induced liver injury and to elucidate its engaged mechanism. Baicalin alleviated APAP-induced hepatic parenchymal cells injury and enhanced the number of mitotic and proliferating cell nuclear antigen (PCNA)-positive hepatocytes in APAP-intoxicated mice. Baicalin increased hepatic PCNA and cyclinD1 expression in APAP-intoxicated mice. Baicalin induced the activation of NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasome, leading to the increased hepatic expression of interleukin-18 (IL-18) and IL-1β in APAP-intoxicated mice. The results in vitro demonstrated that IL-18 promoted the proliferation of human normal liver L-02 cells. Moreover, the baicalin-provided promotion on liver regeneration in APAP-intoxicated mice was diminished after the application of NLRP3 inhibitor MCC950 and the recombinant mouse IL-18 binding protein (rmIL-18BP). Baicalin induced the cytosolic accumulation of nuclear factor erythroid 2-related factor 2 (Nrf2), and increased the interaction between Nrf2 with Nlrp3, ASC and pro-caspase-1 in livers from APAP-intoxicated mice. Furthermore, the baicalin-provided NLRP3 inflammasome activation and promotion on liver regeneration after APAP-induced liver injury in wild-type mice were diminished in Nrf2 knockout mice. In conclusion, baicalin promoted liver regeneration after APAP-induced acute liver injury in mice via inducing Nrf2 accumulation in cytoplasm that led to NLRP3 inflammasome activation, and then caused the increased expression of IL-18, which induced hepatocytes proliferation.

Baicalin Is Curative Against Rotavirus Damp Heat Diarrhea by Tuning Colonic Mucosal Barrier and Lung Immune Function

BACKGROUND

Previous studies have indicated that rotavirus (RV) is a causative factor for diarrhea and gastroenteritis in pediatric and neonatal settings. Baicalin has many functions, including antibacterial, antiinflammatory, and antihypertensive activities. However, the immunological mechanism of RV-induced diarrhea with heat-dampness syndrome (RV-DH) remains unclear.

AIMS

The aim of this study is to explore the role of baicalin in RV-DH diarrhea and its underlying mechanism.

METHODS

A mouse model of pediatric RV-DH diarrhea was established and treated with baicalin. The concentrations of cytokines were detected by enzyme-linked immunosorbent assay. Messenger RNA (mRNA) expression levels were detected by quantitative real-time polymerase chain reaction (qRT-PCR), while protein expression levels were determined by Western blotting and immunohistochemistry. Flow cytometry was used to detect the frequency of lymphocytes.

RESULTS

The concentrations of interleukin-1β (IL-1β), IL-2, IL-6, IL-8, RVvb, and secretory immunoglobulin A (SIgA) in bronchoalveolar lavage fluid (BALF) and colonic mucosa were significantly increased in the RV-DH group. Decreased expression of occludin, claudin-1, and zonula occludens-1 (ZO-1) indicated loss of tight junction function and disturbances in intestinal mucosal permeability in the RV-DH group. Flow cytometry analysis showed a high rate of CD8⁺ lymphocytes and low amount of CD4⁺ lymphocytes in the RV-DH group. Treatment of RV-DH mice with baicalin significantly reduced the duration of diarrhea and ameliorated the symptoms and pathological and immunological changes. Furthermore, baicalin inhibited STAT1 and activated STAT3 signaling pathways.

CONCLUSIONS

These findings indicate the curative and immunoregulatory properties of baicalin and have direct practical and clinical relevance for the treatment of RV-DH enteritis in humans.

Hepatoprotective effect of polyphenols in rats with experimental thioacetamide-induced toxic liver pathology

Non-alcoholic fatty liver disease is associated with a number of disorders (diabetes, obesity, cardiovascular diseases), and can also be induced by drugs or toxic compounds. Recently the important branch of medicine is the search for effective means of prevention and treatment of fatty hepatosis. Our work was aimed to study the effect of some biologically active natural polyphenols (resveratrol and pinosylvin stilbenes as well as dihydromyricetin dihydroflavonol) on the function and histologic features of the liver. In the experimental model of thioacetamide-induced toxic hepaptitis, the male rats of the Wistar line daily received the effective doses of polyphenols intragastically by gavage together with 0.05% thioacetamide added to drinking water. All studied polyphenols contributed to stabilization of rat weight and a two-fold significant (p < 0.05) decrease in the level of direct bilirubin in the blood serum of animals treated with thioacetamide. Histological analysis of the liver confirmed a decrease in inflammation and hemorrhage in animals treated with polyphenols amid continued administration of thioacetamide for 30 days. Based on the data obtained, it can be concluded that the natural polyphenols which belong to the classes of dihydroflavonols (dihydromyricetin) and stilbenes (resveratrol and pinosylvin) have a positive effect on liver function in the experimental model of toxic hepatosis. The studied polyphenols can be considered as potential hepatoprotective drugs used as a part of the liver diseases complex therapy.

Hepatoprotective and anti-inflammatory effects of total flavonoids of Qu Zhi Ke (peel of Citrus changshan-huyou) on non-alcoholic fatty liver disease in rats via modulation of NF-κB and MAPKs

BACKGROUND

Citrus flavonoids, consisting of naringin, narirutin, neohesperidine, etc., have therapeutic activities for the treatment of lipometabolic disorders. The peel of Citrus changshan-huyou (Qu Zhi Ke, QZK) is a new source of flavonoids, but attracted little attention so far.

HYPOTHESIS

QZK should possess therapeutic effects against lipometabolic disorders due to the flavonoids it contains.

STUDY DESIGN

In this study, we extracted and purified the flavonoids of QZK (TFCH) and established an obesity-induced non-alcoholic fatty liver disease (NAFLD) model of rats. TFCH was given orally for 8 weeks, and its anti-NAFLD effects and potential mechanism were evaluated.

METHODS

The flavonoid chemoprofile of TFCH was determined by using HPLC. High-fat diet was employed to induce NAFLD model in rats, and six groups were set up: negative control group, reference treatment group, model group, low-dose TFCH (25 mg/kg), intermediate-dose TFCH (50 mg/kg), and high-dose TFCH (100 mg/kg). Serum and liver levels of inflammatory cytokines and NAFLD markers were measured biochemically. The relative mRNA expressions of liver T-bet, GATA3, and TNF-α were tested by real time PCR (qPCR) analysis. The protein expression of p38 and the phosphorylation of NF-κB, ERK1/2, and p38 in liver were tested by Western blot analysis.

RESULTS

The histopathological observation showed that TFCH attenuated hepatic lesions with significantly decreased NAFLD activity scores. The biochemical data showed that TFCH significantly suppressed both systemic and intrahepatic inflammation by inhibiting IL-1β, IL-6, IL-12, TNF-α, and IFN-γ, and the qPCR analysis revealed a Th1/Th2 related anti-inflammatory mechanism of TFCH. Western blot results clarified that TFCH exerted hepatoprotective and anti-inflammatory effects by suppression of phosphorylated NF-κB and MAPKs, indicating a mechanism associated with NF-κB and MAPK signaling pathways.

CONCLUSION

QZK is a new source of Citrus flavonoids for therapeutic use, and TFCH is a promising representative of Citrus flavonoids for anti-NAFLD therapy.

Baicalin Protects against Thrombin-Induced Cell Injury in Human Umbilical Vein Endothelial Cells

Thrombin plays a pivotal role in the pathogenesis of atherosclerosis. Baicalin, an active flavonoid compound, was shown to attenuate the development of atherosclerosis, but the mechanism remains elusive. In the present study, the role and mechanism of baicalin in thrombin-induced cell injury was investigated in human umbilical vein endothelial cells (HUVECs). Our results showed that baicalin significantly reduced thrombin-induced apoptosis of HUVECs. Additional experiments showed that baicalin inhibited thrombin-induced NF-κB activation and PAR-1 expression. In addition, baicalin decreased thrombin-induced PAR-1 expression by inhibiting ERK pathway. These results indicated that baicalin has protective effects on thrombin-induced cell injury in HUVECs possibly through inhibition of PAR-1 expression and its downstream NF-κB activation, which was mediated by ERK1/2 activation.

Baicalin modulates apoptosis via RAGE, MAPK, and AP-1 in vascular endothelial cells during Haemophilus parasuis invasion

Glässer’s disease, caused by Haemophilus parasuis, is a chronic disease related to an inflammatory immune response. Baicalin exerts important biological functions. In this study, we explored the protective efficacy of treatment with baicalin and the potential mechanism of activation of the MAPK signaling pathway in porcine aortic vascular endothelial cells (PAVECs) induced by H. parasuis. H. parasuis stimulated expression of receptor for advanced glycation end products, induced a significant increase in the level of protein kinase-α and protein kinase-δ phosphorylation, and significantly up-regulated ERK, c-Jun N-terminal kinase, and p38 phosphorylation in PAVECs. H. parasuis also up-regulated the levels of apoptotic genes (Bax, C-myc, and Fasl) and the expression levels of c-Jun and c-Fos, and induced S-phase arrest in PAVECs. However, treatment with baicalin inhibited expression of RAGE, suppressed H. parasuis-induced protein kinase-α and protein kinase-δ phosphorylation, reduced ERK, c-Jun N-terminal kinase, and p38 phosphorylation, down-regulated apoptotic genes (Bax, C-myc, and Fasl), attenuated phospho-c-Jun production from the extracellular to the nuclei, and reversed S-phase arrest in PAVECs. In conclusion, baicalin treatment inhibited the MAPK signaling pathway, thereby achieving its anti-inflammatory responses, which provides a new strategy to control H. parasuis infection.

Tempol Protects Against Acetaminophen Induced Acute Hepatotoxicity by Inhibiting Oxidative Stress and Apoptosis

Acetaminophen (APAP)-induced acute hepatotoxicity is the leading cause of drug-induced acute liver failure. The aim of this study was to evaluate the effects of 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (tempol) on the protection of APAP-induced hepatotoxicity in mice. Mice were pretreated with a single dose of tempol (20 mg/kg per day) orally for 7 days. On the seventh day, mice were injected with a single dose of APAP (300 mg/kg) to induce acute hepatotoxicity. Our results showed that tempol treatment markedly improved liver functions with alleviations of histopathological damage induced by APAP. Tempol treatment upregulated levels of antioxidant proteins, including superoxide dismutase, catalase, and glutathione. Also, phosphorylation of phosphoinositide 3-kinase (PI3K) and protein kinase B (Akt) and protein expression of nuclear factor erythroid 2-related factor (Nrf 2) and heme oxygense-1 (HO-1) were all increased by tempol, which indicated tempol protected against APAP-induced hepatotoxicity via the PI3K/Akt/Nrf2 pathway. Moreover, tempol treatment decreased pro-apoptotic protein expressions (cleaved caspase-3 and Bax) and increased anti-apoptotic Bcl-2 in liver, as well as reducing apoptotic cells of TUNEL staining, which suggested apoptotic effects of tempol treatment. Overall, we found that tempol normalizes liver function in APAP-induced acute hepatotoxicity mice via activating PI3K/Akt/Nrf2 pathway, thus enhancing antioxidant response and inhibiting hepatic apoptosis.

Ethnobotany, Phytochemistry and Pharmacological Properties of Eucommia ulmoides: A Review

Eucommia ulmoides Oliver, a single species of Eucommia genus belonging to the Eucommiaceae family, is an endemic in China and has been used in traditional Chinese medicine for nearly two thousand years. Records from different historical periods highlight E. ulmoides and its officinal botanical parts, usefulness in adaptation to disease and its central role in Chinese medicine theory. There are also historical collection documents for minorities in China. Tearing the leaves, bark and fruit produces strands of latex; a description of E. ulmoides’s morphological features is recorded in this paper. This review summarizes 204 natural compounds isolated from this plant, which are divided into seven categories: lignans, iridoids, flavonoids, phenols, steroids, terpenes and others. These components possess wide-ranging pharmacological efficacies, such as antihypertensive, antihyperglycemic, antihyperlipidemia, anti-oxidative, anti-osteoporosis, antitumor, immunomodulatory and neuroprotective activities. This review aims to provide a reference for extensive researches of E. ulmoides crude drugs, especially for quality control, biosynthesis and structure modification of active ingredients and pharmacological mechanism.

Molecular mechanism and research progress on pharmacology of traditional Chinese medicine in liver injury

CONTEXT

Liver disease is a common threat to human health, caused by a variety of factors that damage the liver. Recent studies have shown that active ingredients (for example: flavonoids, saponins, acids, phenols, and alkaloids) from Traditional Chinese Medicine (TCM) can have hepatoprotective benefits, which represents an attractive source of drug discovery for treating liver injury.

OBJECTIVE

We reviewed recent contributions on the chemically induced liver injury, immunological liver damage, alcoholic liver injury, and drug-induced liver injury, in order to summarize the research progress in molecular mechanism and pharmacology of TCM, and provides a comprehensive overview of new TCM treatment strategies for liver disease.

MATERIALS AND METHODS

Relevant literature was obtained from scientific databases such as Pubmed, Web of Science. and CNKI databases on ethnobotany and ethnomedicines (from January 1980 to the end of May 2018). The experimental studies involving the antihepatic injury role of the active agents from TCM and the underlying mechanisms were identified. The search terms included 'liver injury' or 'hepatic injury', and 'traditional Chinese medicine', or 'herb'.

RESULTS

A number of studies revealed that the active ingredients of TCM exhibit potential therapeutic benefits against liver injury, while the underlying mechanisms appear to contribute to the regulation of inflammation, oxidant stress, and pro-apoptosis signaling pathways.

DISCUSSION AND CONCLUSIONS

The insights provided in this review will help further exploration of botanical drugs in the development of liver injury therapy via study on the effective components of TCM.

Therapeutic Potential of Plants and Plant Derived Phytochemicals against Acetaminophen-Induced Liver Injury

Acetaminophen (APAP), which is also known as paracetamol or N-acetyl-p-aminophenol is a safe and potent drug for fever, pain and inflammation when used at its normal therapeutic doses. It is available as over-the-counter drug and used by all the age groups. The overdose results in acute liver failure that often requires liver transplantation. Current clinical therapy for APAP-induced liver toxicity is the administration of N-acetyl-cysteine (NAC), a sulphydryl compound an approved drug which acts by replenishing cellular glutathione (GSH) stores in the liver. Over the past five decades, several studies indicate that the safety and efficacy of herbal extracts or plant derived compounds that are used either as monotherapy or as an adjunct therapy along with conventional medicines for hepatotoxicity have shown favorable responses. Phytochemicals mitigate necrotic cell death and protect against APAP-induced liver toxicityby restoring cellular antioxidant defense system, limiting oxidative stress and subsequently protecting mitochondrial dysfunction and inflammation. Recent experimental evidences indicat that these phytochemicals also regulate differential gene expression to modulate various cellular pathways that are implicated in cellular protection. Therefore, in this review, we highlight the role of the phytochemicals, which are shown to be efficacious in clinically relevant APAP-induced hepatotoxicity experimental models. In this review, we have made comprehensive attempt to delineate the molecular mechanism and the cellular targets that are modulated by the phytochemicals to mediate the cytoprotective effect against APAP-induced hepatotoxicity. In this review, we have also defined the challenges and scope of phytochemicals to be developed as drugs to target APAP-induced hepatotoxicity.

Recent Advances in Drug Delivery System for Bioactive Glycosides from Traditional Chinese Medicine

Traditional Chinese Medicine (TCM) has been used in China for thousands of years for the prevention and treatment of various diseases. The materials that exert a therapeutic effect are called the active ingredients. The bioactive glycosides are important active ingredients from TCM that can make significant contributions to treating diseases. Because of the possibilities of various clinical applications, the properties and administration of these bioactive glycosides deserve further investigation. Their promising treatment effects, however, are hindered by their poor solubility, poor stability and rapid elimination. Therefore, it is necessary that we improve the therapeutic efficacy of bioactive glycosides by overcoming these problems. Meanwhile, some practical design strategies and novel drug delivery vehicles based on drug delivery systems provide favorable support in clinical practice for these active ingredients. This review summarizes diverse pharmacological activities of bioactive glycosides and focuses on recent advances in delivery system for these active constitutes; in particular, some glycol glycosides can effectively cure intractable diseases through targeted drug delivery. This review elucidates some design strategies for drug delivery system that are mainly based on two methods (avoiding physical barriers by changing dosage forms and enhancing the ability to bind to receptors or proteins after administration) and indicate the current challenges during the combination of delivery vehicles and these glycosides in hopes of promoting the process of receiving ideal therapeutic efficacy of them in future studies.

Protective effect of Epicatechin on APAP-induced acute liver injury of mice through anti-inflammation and apoptosis inhibition

Epicatechin (EC) is the most effective compound in Euonymus alatus (Thunb.)Sieb, and possesses a series of benefits, including anti-inflammatory, antioxidant, antiobesity and anticancer effects. In this study, we investigated the protective effects of EC in Acetaminophen(N-acetyl-p-aminophenol, APAP)-induced acute liver injury in C57BL/6J mice and explored the possible mechanisms involved in these effects.[Formula: see text].

Biomarkers associated with binaprofen‑induced liver injury

Drug‑induced liver injury (DILI) is a common hepatic disease. The identification of biomarkers for DILI prediction is critical for rational drug use. The aim of the present study was to investigate liver injury caused by binaprofen and identify proteins that may serve as early biomarkers to predict DILI. For in vivo DILI assays, zebrafish were exposed to acetaminophen (APAP) and binaprofen for 12‑96 h before lethal concentration 50 (LC50), histopathological analysis, conventional and non‑conventional biomarker measurements were conducted. In vitro assays were performed in cultured liver cells; after 6‑24 h treatment with APAP and binaprofen the same measurements were conducted as aforementioned. The in vivo assays indicated that the LC50 of APAP was 5.2 mM, whereas the LC50 of binaprofen was 1.2 mM; 12‑48 h post‑treatment, liver cells exhibited mild to moderate vacuolization in a time‑ and concentration‑dependent manner in response to both drugs. During this time, conventional and non‑conventional biomarkers were also altered in a time‑ and concentration‑dependent manner; however, alterations in the levels of non‑conventional biomarkers occurred at an earlier time point compared with conventional biomarkers. The in vitro assays indicated that the half maximal inhibitory concentration (IC50) of APAP was 16.2 mM, whereas the IC50 of binaprofen was 5.3 mM; 12‑48 h post‑treatment, cultured liver cells exhibited mild to moderate swelling in a time‑ and concentration‑dependent manner. Alterations in the levels of conventional and non‑conventional biomarkers were similar to those observed in the in vivo assays. As a non‑steroidal anti‑inflammatory drug, binaprofen exhibited expected levels of liver toxicity in in vitro and in vivo assays, which were similar to APAP. Total bile acid and argininosuccinate lyase were identified as early biomarkers, which could accurately predict onset of binaprofen‑induced liver injury.

Preliminary studies on therapeutic effect of ethanolic extract of Tylophora villosa leaves against paracetamol-induced hepatotoxicity in mice

This study intended to investigate the therapeutic effect of ethanolic extract of Tylophora villosa leaves (E2TL) against paracetamol (PC)-induced hepatotoxicity (PCIH) in mice (Mus musculus). PCIH were generated using daily 250 mg/kg body weight (bw) PC administration by gavage for seven days, and then daily 27.5; 55.0; 82.5; 110.0; or 220.0 mg/kg bw E2TL were treated by gavage for seven or fourteen days. Meanwhile, the controls were given solvent only in the same manner. Mortality, blood glucose, and condition (color, weight, volume) of the livers were observed on day 15 (D15). Serum glutamate pyruvate transaminase (SGPT) and serum glutamate oxaloacetate transaminase (SG0T) were examined on D15, D22, and D30, and then malondialdehyde (MDA) was determined on D15. Results of this study revealed that on D15, the dosage of 110.0 mg/kg bw E2TL most effectively decreased MDA due to PCIH, from 6.78 ± 1.70 μmol/L to 3.45 ± 0.43 μmol/L, approaching the control condition (2.45 ± 0.05 μmol/L). PC administration was really toxic dosage and caused 13.3 % mortality. Blood glucose, weight, and volume of the liver decreased as the effect of PC administration, and then 220.0 mg/kg bw E2TL treatment could recover the condition as well as the controls. Color of the liver indicated a similar recovery by E2TL treatment. SGPT and SG0T increased significantly by PC administration, and this PCIH facts could be recovered gradually near the controls according to the dosages (55.0; 110.0; or 220.0 mg/kg bw) and duration (seven or fourteen days) of E2TL treatment. It could be concluded that E2TL showed therapeutic effect against PCIH in M. musculus.

Hepatoprotective Effect of Ugonin M, A Helminthostachyszeylanica Constituent, on Acetaminophen-Induced Acute Liver Injury in Mice

The present study aimed to discover the possible effectiveness of Ugonin M, a unique flavonoid isolated from Helminthostachys zeylanica-a traditional Chinese medicine used as anti-inflammatory medicine-and to elucidate the potential mechanisms of Ugonin M in the acute liver injury induced by acetaminophen (APAP). In this study, Ugonin M significantly ameliorated APAP-induced histopathological changes and the typical liver function biomarkers (i.e., alanine aminotransferase (ALT), aspartate aminotransferase (AST), and total bilirubin (T-Bil)). It also affected APAP-induced abnormal lipid metabolism including total cholesterol (TC) and triglyceride (TG) in the serum. In inflammatory pharmacological action, Ugonin M suppressed the pro-inflammatory mediators such as nitric oxide (NO) and the lipid peroxidation indicator malondialdehyde (MDA). In addition, Ugonin M reinforced hemeoxygenase-1 (HO-1) protein expression and the production of antioxidant enzymes viz superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT). Furthermore, inflammation-associated cytokines including tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and IL-1β as well as proteins such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were decreased by the pretreatment of Ugonin M. Moreover, this study found that pretreatment of Ugonin M apparently decreased nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinases (MAPKs) activation via inhibition of the degradation of NF-κB, inhibitory κB-α (IκB-α), extracellular regulated kinase (ERK), c-Jun-N-terminal (JNK), and p38 active phosphorylation. In conclusion, Ugonin M significantly showed a protective effect against APAP-induced liver injury by reducing oxidative stress and inflammation. Thus, Ugonin M could be one of the effective components of H. zeylanica that plays a major role in the treatment of inflammatory disorders.

Metabolomic Assessment of Acute Cholestatic Injuries Induced by Thioacetamide and by Bile Duct Ligation, and the Protective Effects of Huang-Lian-Jie-Du-Decoction

Huang-Lian-Jie-Du-Decoction, a traditional Chinese formula, has been reported to protect liver from various injuries. Two cholestasis models of rats induced by thioacetamide and by bile duct ligation were established and treated with Huang-Lian-Jie-Du-Decoction. Nuclear Magnetic Resonance-based urinary metabolic profiles were analyzed by orthogonal partial least squares discriminant analysis and univariate analysis to excavate differential metabolites associated with the injuries of the two models and the treatment effects of Huang-Lian-Jie-Du-Decoction. The two cholestatic models shared common metabolic features of excessive fatty acid oxidation, insufficient glutathione regeneration and disturbed gut flora, with specific characteristics of inhibited urea cycle and DNA damage in thioacetamide-intoxicated model, and perturbed Kreb's cycle and inhibited branched chain amino acid oxidation in bile duct ligation model. With good treatment effects, Huang-Lian-Jie-Du-Decoction could regain the balance of the disturbed metabolic status common in the two cholestasis injuries, e.g., unbalanced redox system and disturbed gut flora; and perturbed urea cycle in thioacetamide-intoxicated model and energy crisis (disturbed Kreb's cycle and oxidation of branched chain amino acid) in bile duct ligation model, respectively.

The Potential and Action Mechanism of Polyphenols in the Treatment of Liver Diseases

Liver disease, involving a wide range of liver pathologies from fatty liver, hepatitis, and fibrosis to cirrhosis and hepatocellular carcinoma, is a serious health problem worldwide. In recent years, many natural foods and herbs with abundant phytochemicals have been proposed as health supplementation for patients with hepatic disorders. As an important category of phytochemicals, natural polyphenols have attracted increasing attention as potential agents for the prevention and treatment of liver diseases. The striking capacities in remitting oxidative stress, lipid metabolism, insulin resistance, and inflammation put polyphenols in the spotlight for the therapies of liver diseases. It has been reported that many polyphenols from a wide range of foods and herbs exert therapeutic effects on liver injuries via complicated mechanisms. Therefore, it is necessary to have a systematical review to sort out current researches to help better understand the potentials of polyphenols in liver diseases. In this review, we aim to summarize and update the existing evidence of natural polyphenols in the treatment of various liver diseases by in vitro, in vivo, and clinical studies, while special attention is paid to the action mechanisms.