Hepatoprotective effect of Baicalin against thioacetamide-induced cirrhosis in rats: Targeting NOX4/NF-κB/NLRP3 inflammasome signaling pathways

Plant-derived flavonoids are a potential source of drugs for the treatment of liver fibrosis

Liver fibrosis is a dynamic pathological process that can be triggered by any chronic liver injury. If left unaddressed, it will inevitably progress to the severe outcomes of liver cirrhosis or even hepatocellular carcinoma. In the past few years, the prevalence and fatality of hepatic fibrosis have been steadily rising on a global scale. As a result of its intricate pathogenesis, the quest for pharmacological interventions targeting liver fibrosis has remained a formidable challenge. Currently, no pharmaceuticals are exhibiting substantial clinical efficacy in the management of hepatic fibrosis. Hence, it is of utmost importance to expedite the development of novel therapeutics for the treatment of this condition. Various research studies have revealed the ability of different natural flavonoid compounds to alleviate or reverse hepatic fibrosis through a range of mechanisms, which are related to the regulation of liver inflammation, oxidative stress, synthesis and secretion of fibrosis-related factors, hepatic stellate cells activation, and proliferation, and extracellular matrix synthesis and degradation by these compounds. This review summarizes the progress of research on different sources of natural flavonoids with inhibitory effects on liver fibrosis over the last decades. The anti-fibrotic effects of natural flavonoids have been increasingly studied, making them a potential source of drugs for the treatment of liver fibrosis due to their good efficacy and biosafety.

Functional Food Chemical Ingredient Strategies for Non-alcoholic Fatty Liver Disease (NAFLD) and Hepatic Fibrosis: Chemical Properties, Health Benefits, Action, and Application

PURPOSE OF REVIEW

The liver is an important digestive gland in the body. Lifestyle and dietary habits are increasingly damaging our liver, leading to various diseases and health problems. Non-alcoholic fatty liver disease (NAFLD) has become one of the most serious liver disease problems in the world. Diet is one of the important factors in maintaining liver health. Functional foods and their components have been identified as novel sources of potential preventive agents in the prevention and treatment of liver disease in daily life. However, the effects of functional components derived from small molecules in food on different types of liver diseases have not been systematically summarized.

RECENT FINDINGS

The components and related mechanisms in functional foods play a significant role in the development and progression of NAFLD and liver fibrosis. A variety of structural components are found to treat and prevent NAFLD and liver fibrosis through different mechanisms, including flavonoids, alkaloids, polyphenols, polysaccharides, unsaturated fatty acids, and peptides. On the other hand, the relevant mechanisms include oxidative stress, inflammation, and immune regulation, and a large number of literature studies have confirmed a close relationship between the mechanisms. The purpose of this article is to examine the current literature related to functional foods and functional components used for the treatment and protection against NAFLD and hepatic fibrosis, focusing on chemical properties, health benefits, mechanisms of action, and application in vitro and in vivo. The roles of different components in the biological processes of NAFLD and liver fibrosis were also discussed.

Hispidulin exerts a protective effect against oleic acid induced-ARDS in the rat via inhibition of ACE activity and MAPK pathway

This study investigates the protective role of Hispidulin on acute respiratory distress syndrome (ARDS) in rats. Rats were divided into three groups: control, ARDS, ARDS+ Hispidulin. The ARDS models were established by injecting rats with oleic acid. Hispidulin (100 mg/kg) was injected i.p. an hour before ARDS. Myeloperoxidase (MPO), Interleukin-8 (IL-8), Mitogen-activated protein kinases (MAPK), Lipid Peroxidation (LPO), Superoxide Dismutase (SOD), Glutathione (GSH), and Angiotensin-converting enzyme (ACE) were determined by ELISA. Tumor necrosis factor-alpha (TNF-α) expression was described by RT-qPCR. Caspase-3 immunostaining was performed to evaluate apoptosis. Compared with the model group, a significant decrease was observed in the MPO, IL-8, MAPK, ACE, LPO levels, and TNF-α expression in the ARDS+ Hispidulin group. Moreover, reduced caspase-3 immunoreactivity and activity of ACE were detected in the Hispidulin+ARDS group. The protective effect of Hispidulin treatment may act through inhibition of the ACE activity and then regulation of inflammatory cytokine level and alteration of apoptosis.

Restraint stress promotes nonalcoholic steatohepatitis by regulating the farnesoid X receptor/NLRP3 signaling pathway

Psychological stress promotes nonalcoholic steatohepatitis (NASH) development. However, the pathogenesis of psychological stress-induced NASH remains unclear. This study aims to explore the underlying mechanism of restraint stress-induced NASH, which mimics psychological stress, and to discover potential NASH candidates. Methionine choline deficient diet- and high fat diet-induced hepatosteatotic mice are subjected to restraint stress to induce NASH. The mice are administrated with Xiaoyaosan granules, NOD-like receptor family pyrin domain containing 3 (NLRP3) inhibitors, farnesoid X receptor (FXR) agonists, or macrophage scavengers. Pathological changes and NLRP3 signaling in the liver are determined. These results demonstrate that restraint stress promotes hepatic inflammation and fibrosis in hepatosteatotic mice. Restraint stress increases the expressions of NLRP3, Caspase-1, Gasdermin D, interleukin-1β, cholesterol 7α-hydroxylase, and sterol 12α-hydroxylase and decreases the expression of FXR in NASH mice. Xiaoyaosan granules reverse hepatic inflammation and fibrosis and target FXR and NLRP3 signals. In addition, inhibition of NLRP3 reduces the NLRP3 inflammasome and liver damage in mice with restraint stress-induced NASH. Elimination of macrophages and activation of FXR also attenuate inflammation and fibrosis by inhibiting NLRP3 signaling. However, NLRP3 inhibitors or macrophage scavengers fail to affect the expression of FXR. In conclusion, restraint stress promotes NASH-related inflammation and fibrosis by regulating the FXR/NLRP3 signaling pathway. Xiaoyaosan granules, NLRP3 inhibitors, FXR agonists, and macrophage scavengers are potential candidates for the treatment of psychological stress-related NASH.

Hepatoprotective Effects of Biochanin A on Thioacetamide-Induced Liver Cirrhosis in Experimental Rats

The protective effect of biochanin A (BCA) on the histopathology, immunohistochemistry, and biochemistry of thioacetamide (TAA)-induced liver cirrhosis in vivo was investigated. There was a significant reduction in liver weight and hepatocyte propagation, with much lower cell injury in rat groups treated with BCA (25 mg/kg and 50 mg/kg) following a TAA induction. These groups had significantly lower levels of proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (α-SMA). The liver homogenates showed increased antioxidant enzyme activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx), as well as decreased malondialdehyde (MDA) levels. The serum biomarkers associated with liver function, namely alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and gamma glutamyl transaminase (GGT), returned to normal levels, comparable to those observed in both the normal control group and the reference control group. Taken together, the normal microanatomy of hepatocytes, the inhibition of PCNA and α-SMA, improved antioxidant enzymes (SOD, CAT, and GPx), and condensed MDA with repairs of liver biomarkers validated BCA's hepatoprotective effect.

Formulation of lipid polymer hybrid nanoparticles of the phytochemical Fisetin and its in vivo assessment against severe acute pancreatitis

Fisetin (FST) is a naturally occurring flavonol that has recently emerged as a bioactive phytochemical with an impressive array of biological activities. To the author knowledge, boosting the activity of FST against severe acute pancreatitis (SAP) through a nanostructured delivery system (Nanophytomedicine) has not been achieved before. Thereupon, FST-loaded lipid polymer hybrid nanoparticles (FST-loaded LPHNPs) were prepared through conjoined ultrasonication and double emulsion (w/o/w) techniques. Comprehensive in vitro and in vivo evaluations were conducted. The optimized nanoparticle formula displayed a high entrapment efficiency % of 61.76 ± 1.254%, high loading capacity % of 32.18 ± 0.734, low particle size of 125.39 ± 0.924 nm, low particle size distribution of 0.357 ± 0.012, high zeta potential of + 30.16 ± 1.416 mV, and high mucoadhesive strength of 35.64 ± 0.548%. In addition, it exhibited a sustained in vitro release pattern of FST. In the in vivo study, oral pre-treatment of FST-loaded LPHNPs protected against L-arginine induced SAP and multiple organ injuries in rats compared to both FST alone and plain LPHNPs, as well as the untreated group, proven by both biochemical studies, that included both amylase and lipase activities, and histochemical studies of pancreas, liver, kidney and lungs. Therefore, the study could conclude the potential efficacy of the novel phytopharmaceutical delivery system of FST as a prophylactic regimen for SAP and consequently, associated multiple organ injuries.

Biased Quantification of Rat Liver Fibrosis-Meta-Analysis with Practical Recommendations and Clinical Implications

For liver fibrosis assessment, the liver biopsy is usually stained with Masson's trichrome (MT) or picrosirius red (PSR) to quantify liver connective tissue (LCT) for fibrosis scoring. However, several concerns of such semiquantitative assessments have been raised, and when searching for data on the amount of LCT in healthy rats, the results vastly differ. Regarding the ongoing reproducibility crisis in science, it is necessary to inspect the results and methods, and to design an unbiased and reproducible method of LCT assessment. We searched the Medline database using search terms related to liver fibrosis, LCT and collagen, rat strains, and staining methods. Our search identified 74 eligible rat groups in 57 studies. We found up to 170-fold differences in the amount of LCT among healthy Wistar and Sprague-Dawley rats, with significant differences even within individual studies. Biased sampling and quantification probably caused the observed differences. In addition, we also found incorrect handling of liver fibrosis scoring. Assessment of LCT using stereological sampling methods (such as systematic uniform sampling) would provide us with unbiased data. Such data could eventually be used not only for the objective assessment of liver fibrosis but also for validation of noninvasive methods of the assessment of early stages of liver fibrosis.

Ameliorative effect of desloratadine against cisplatin-induced renal and testicular toxicity in rats: Attention to TLR4/NLRP3 inflammasome signaling pathway

Cisplatin (CIS) is a potent anticancer drug that is used in the treatment of different types of cancer. Owing to its serious side effects, its clinical use is considerably limited.

AIMS

This study was mapped to investigate the potential effects of desloratadine (DES) against CIS-induced nephrotoxicity and testicular injury.

MAIN METHODS

DES (5 and 10 mg/kg) was orally administered for 10 days, and CIS was injected once (10 mg/kg, i.p.) in adult male rats on day 9 to induce both renal and testicular toxicity.

KEY FINDINGS

DES significantly attenuated CIS-induced alterations in histopathology and biomarkers. DES resulted in a significant reduction in serum levels of creatinine (Cr), urea, and blood urea nitrogen (BUN), in addition to a marked decrease in urinary levels of albumin and total protein. Additionally, DES efficiently reinstated the oxidative balance by preventing the elevation of malondialdehyde (MDA) and enhancing superoxide dismutase (SOD) activity, and increasing glutathione (GSH) levels. Moreover, DES produced a profound decrease in renal and testicular levels of nucleotide-binding domain-(NOD) like receptor 3 (NLRP3), interleukin (IL)-1β, and caspase-1 when compared to the CIS group. Furthermore, DES significantly decreased CIS-induced elevation in toll-like receptor 4 (TLR4), tumor necrosis factor-alpha (TNF-α), and nuclear factor-kappa B (NF-κB) levels in both renal and testicular tissues.

SIGNIFICANCE

DES can be used as adjuvant therapy with CIS in cancerous cases, pending further clinical studies.

Dysregulated B7H4/JAK2/STAT3 Pathway Involves in Hypertriglyceridemia Acute Pancreatitis and Is Attenuated by Baicalin

BACKGROUND

Patients with hypertriglyceridemia (HTG) are prone to develop more severe acute pancreatitis (AP). However, the specific molecular mechanism still has not been elaborated clearly, and effective drugs for treating HTG-AP are not yet readily available. Baicalin is an ingredient isolated from a natural product that with potential to attenuate inflammation and pain in AP.

AIMS

The aim of the present study was to explore the effect of baicalin on HTG-AP and the possible mechanism involved.

METHODS

A mouse model of HTG-AP was successfully established by administering Poloxamer 407 and L-arginine intraperitoneally. We analyzed pathological changes, and performed TUNEL staining, DHE staining, and western blot to detect apoptosis, inflammation, oxidative stress, and B7H4/JAK2/STAT3 signaling in the pancreas.

RESULTS

Treatment with baicalin decreased serum triglyceride, cholesterol, lipase, amylase levels, and attenuated pancreatic edema. After intervention with baicalin, apoptosis and inflammation in HTG-AP mice were alleviated, as indicated by the decrease of Bax, cleaved-caspase-3, IL-6, TNF-α, and IL-1β. Baicalin also alleviated oxidative stress by decreasing NOX2, increasing SOD2 protein expression, and regulating Nrf2/Keap1 signaling in HTG-AP mice. Furthermore, baicalin decreased the upregulated B7H4/JAK2/STAT3 pathway in HTG-AP.

CONCLUSIONS

In conclusion, our data suggested that baicalin could attenuate HTG-AP, possibly through regulating B7H4/JAK2/STAT3 signaling.

Naringenin mitigates thioacetamide-induced hepatic encephalopathy in rats: targeting the JNK/Bax/caspase-8 apoptotic pathway

Hepatic encephalopathy (HE) is a serious neurological disorder which is related to liver dysfunction. HE was induced by thioacetamide (TAA) injection (350 mg kg^-1, i.p.) for 3 consecutive days. This study was performed to investigate the prophylactic impact of naringenin against TAA-induced HE. Naringenin (100 mg kg^-1) was orally administered for 7 days starting 4 days prior to TAA injection. Naringenin effectively mitigated TAA-induced behavioural, structural and functional alterations. Naringenin ameliorated TAA-induced cognitive impairment as evidenced by the increase in the fall-off time in the rotarod test, decrease in the escape latency in the Morris water maze test and increase in the time spent in the center and in the number of rearing in the open field test. Additionally, naringenin significantly decreased the serum levels of transaminases, alkaline phosphatase, gamma-glutamyl transferase, bile and ammonia. Moreover, naringenin succeeded in reducing the levels of hepatic and cerebral c-Jun N-terminal kinases (JNK) as well as hepatic SORT1 levels. In addition, naringenin successfully elevated the levels of hepatic and cerebral pro-brain-derived neurotrophic factor (pro-BDNF) and BDNF in addition to the cerebral SORT1 level. Finally, naringenin markedly decreased the expression of Bax and caspase-8 as presented by the immunohistochemical results. Collectively, the ameliorative effect of naringenin on the development of HE might be attributed to the modulation of the JNK/Bax/caspase-8 apoptotic pathway.

XCHT alleviates the pancreatic fibrosis via VDR/NLRP3 signaling pathway in a mouse model of CP

ETHNOPHARMACOLOGICAL RELEVANCE

Xiao Chai Hu Tang (XCHT) derived from the classic medical book Shang Han Lun (Treatise on Febrile Diseases) in the Eastern Han Dynasty, which has been widely used in China and other Asian countries for the treatment of inflammation and fibrosis of chronic pancreatitis (CP), but the therapeutic mechanism of XCHT in pancreatic fibrosis remains unclear.

AIM OF THE STUDY

This study aimed to evaluate the intervention effects and explore pharmacological mechanism of XCHT on inflammation and fibrosis in cerulein-induced CP model.

MATERIALS AND METHODS

Fifty male C57BL/6 mice were randomly divided into five main groups, 10 animals in each: Control, CP model (50 μg/kg cerulein), high dose XCHT-treated CP group (60 g/kg XCHT), medium dose XCHT-treated CP group (30 g/kg XCHT) and low dose XCHT-treated CP group (15 g/kg XCHT). Different doses of XCHT were given to mice by gavage twice a day for 2 weeks after the CP model induction. Pancreatic tissues were harvested and the pancreatic inflammation and fibrosis were evaluated by histological score, Sirius red staining, and alpha-smooth muscle actin (α-SMA) immunohistochemical staining. ELISA, IHC and RT-qPCR were performed to detect the expression of Vitamin D₃ (VD₃) and Vitamin D receptor (VDR) in serum and pancreatic tissues, respectively. The expressions of NLRP3 inflammasome related genes and molecules were assayed by WB, IHC and RT-qPCR.

RESULTS

The pathohistological results demonstrated that XCHT markedly inhibited the fibrosis and chronic inflammation of cerulein-induced CP, indicated by reduction of collagen I, collagen III, α-SMA, and NLRP3 expressions. XCHT significantly increased VD₃ and VDR expression while reduced the pancreatic NLRP3 expression. Correspondingly, XCHT decreased the levels of NLRP3 downstream targets IL-1β, TNF-α and IL-6.

CONCLUSIONS

These results revealed that XCHT suppressed the pancreatic fibrosis and chronic inflammation in cerulein-induced CP model by enhancing the VD₃/VDR expression and inhibiting the secretion of NLRP3-assoicated inflammatory factors.

CD44-Targeting Drug Delivery System of Exosomes Loading Forsythiaside A Combats Liver Fibrosis via Regulating NLRP3-Mediated Pyroptosis

Liver fibrosis is a progressive pathological process induced by various stimuli and may progress to liver cirrhosis and cancer. Forsythiaside A (FA) is an active ingredient extracted from traditional Chinese medicine Forsythiae Fructus and has prominent hepatoprotective activities. However, the unsatisfactory pharmacokinetic properties restrict its clinical application. In this study, the nanocarrier of CD44-specific ligand Hyaluronic acid (HA)-modified milk-derived exosomes (mExo) encapsulated with FA (HA-mExo-FA) is developed. As a result, HA modification could deliver drug-loaded exosomes to the target cells and form a specific ligand-receptor interaction with CD44, thus improving the anti-liver fibrosis effect of FA. In vitro findings indicate that HA-mExo-FA could inhibit TGF-β1-induced LX2 cell proliferation, reduce α-SMA and collagen gene and protein levels, and promote the apoptosis of activated LX2 cells. In vivo results demonstrate that HA-mExo-FA could improve liver morphology and function changes in zebrafish larvae. The anti-liver fibrosis mechanism of HA-mExo-FA may be attributed to the inhibition of NLRP3-mediated pyroptosis. In addition, the effect of HA-mExo-FA on TAA-induced increase in NLRP3 production is attenuated by NLRP3 inhibitor MCC950. Collectively, this study demonstrates the promising application of HA-mExo-FA in drug delivery with high specificity and provides a powerful and novel delivery platform for liver fibrosis therapy.

Potential Therapeutic Implication of Herbal Medicine in Mitochondria-Mediated Oxidative Stress-Related Liver Diseases

Mitochondria are double-membrane organelles that play a role in ATP synthesis, calcium homeostasis, oxidation-reduction status, apoptosis, and inflammation. Several human disorders have been linked to mitochondrial dysfunction. It has been found that traditional therapeutic herbs are effective on alcoholic liver disease (ALD) and nonalcoholic fatty liver disease (NAFLD) which are leading causes of liver cirrhosis and hepatocellular carcinoma. The generation of reactive oxygen species (ROS) in response to oxidative stress is caused by mitochondrial dysfunction and is considered critical for treatment. The role of oxidative stress, lipid toxicity, and inflammation in NAFLD are well known. NAFLD is a chronic liver disease that commonly progresses to cirrhosis and chronic liver disease, and people with obesity, insulin resistance, diabetes, hyperlipidemia, and hypertension are at a higher risk of developing NAFLD. NAFLD is associated with a number of pathological factors, including insulin resistance, lipid metabolic dysfunction, oxidative stress, inflammation, apoptosis, and fibrosis. As a result, the improvement in steatosis and inflammation is enough to entice researchers to look into liver disease treatment. However, antioxidant treatment has not been very effective for liver disease. Additionally, it has been suggested that the beneficial effects of herbal medicines on immunity and inflammation are governed by various mechanisms for lipid metabolism and inflammation control. This review provided a summary of research on herbal medicines for the therapeutic implementation of mitochondria-mediated ROS production in liver disease as well as clinical applications through herbal medicine. In addition, the pathophysiology of common liver disorders such as ALD and NAFLD would be investigated in the role that mitochondria play in the process to open new therapeutic avenues in the management of patients with liver disease.

Rutin and selenium nanoparticles protected against STZ-induced diabetic nephropathy in rats through downregulating Jak-2/Stat3 pathway and upregulating Nrf-2/HO-1 pathway

Diabetic nephropathy (DN) is a renal complication of diabetic hyperglycemia. The Signal transducer and activator of transcription 3 (Stat3) is a center molecule of the chronic inflammation causing DN progression. Therefore, the study investigated the possible inhibitory effects of Rutin (Ru) and Selenium (Se), formulated as nanoparticles (SeNPs), on Stat3 pathway in streptozotocin (STZ)-induced DN in Sprague-Dawley rats. Ru (100 mg/kg/orally) and SeNPs (equivalent to 5 mg of Se/kg/orally) were given as treatment for eight weeks. An assessment of fasting blood glucose, renal function biomarkers, GSH, and MDA was carried out spectrophotometrically. ELISA assessment of renal IL-6, NF-κB, TNF-α, Jak-2, and p-Stat3 was performed. Sirt-1, Nrf-2, and HO-1 were assessed immunohistochemically. DN group receiving Ru + SeNPs showed a decrease in fasting blood glucose, serum creatinine, and urea (163.8 ± 22.8, 0.54 ± 0.1, and 53.6 ± 25.7 mg/dl, respectively), compared to the DN group (443.8 ± 42.72, 1.58 ± 0.4, and 281.8 ± 47.35 mg/dl, respectively). In addition, it exhibited elevation in the levels of Sirt-1, Nrf-2 and HO-1 compared to the DN group. Finally, Ru + SeNPs exhibited a significant reduction in IL-6, NF-κB, TNF-α, Jak-2, and p-Stat3 (42.8 ± 10.3, 1.2 ± 0.1, 53.4 ± 3.87, 0.8 ± 0.06 and 1.1 ± 0.2 U/g tissue, respectively) when compared to the DN group (155.3 ± 13.97, 2.8 ± 0.3, 105.5 ± 32.84, 2.03 ± 0.2 and 2.56 ± 0.15 U/g tissue, respectively). Therefore, combining Ru with SeNPs has a potential renoprotective effect against DN by upregulating Nrf-2/HO-1 and downregulating Jak-2/Stat3 Pathways.

Baicalin inhibits necroptosis by decreasing oligomerization of phosphorylated MLKL and mitigates caerulein-induced acute pancreatitis in mice

Necroptosis is a form of regulated necrosis mainly controlled by receptor-interacting protein kinases 3 (RIPK3) and mixed lineage kinase domain-like protein (MLKL). Necroptosis has important roles in defensing against pathogenic infections, but it is also implicated in various inflammatory diseases including pancreatitis. Baicalin, a flavonoid from Scutellaria baicalensis Georgi, has been shown to possess anti-inflammatory and anti-pyroptosis properties, yet it is unclear whether baicalin can inhibit necroptosis and confer protection against necroptosis-related diseases. Here we reported that baicalin significantly inhibited necroptosis in macrophages induced by lipopolysaccharide plus pan-caspase inhibitor (IDN-6556), or by tumor-necrosis factor-α in combination with LCL-161 (Smac mimetic) and IDN-6556 (TSI). Mechanistically, baicalin did not inhibit the phosphorylation of RIPK1, RIPK3 and MLKL, nor membrane translocation of p-MLKL, during necroptotic induction, but instead inhibited p-MLKL oligomerization that is required for executing necroptosis. As intracellular reactive oxygen species (ROS) has been reported to be involved in p-MLKL oligomerization, we assessed the effects of N-acetyl-L-cysteine (NAC), an ROS scavenger, on necroptosis and found that NAC significantly attenuated TSI-induced necroptosis and intracellular ROS production concomitantly with reduced levels of oligomerized p-MLKL, mirroring the effect of baicalin. Indeed, inhibitory effect of baicalin was associated with reduced TSI-induced superoxide (indicating mitochondrial ROS) production and increased mitochondrial membrane potential within cells during necroptosis. Besides, oral administration of baicalin significantly reduced the severity of caerulein-induced acute pancreatitis in mice, an animal model of necroptosis-related disease. Collectively, baicalin can inhibit necroptosis through attenuating p-MLKL oligomerization and confers protection against caerulein-induced pancreatitis in mice.