S-Acetyl-Glutathione Attenuates Carbon Tetrachloride-Induced Liver Injury by Modulating Oxidative Imbalance and Inflammation

Jujuboside B alleviates acetaminophen-induced hepatotoxicity in mice by regulating Nrf2-STING signaling pathway

BACKGROUND

Jujuboside B (JuB) is the main bioactive saponin component of Chinese anti-insomnia herbal medicine Ziziphi Spinosae Semen, which has been reported to possess varied pharmacological functions. Even though it has been traditionally used to treat inflammation- and toxicity-related diseases, the effects of JuB on acetaminophen (APAP) overdose-induced hepatotoxicity have not been determined yet.

METHODS

C57BL/6 J mice were pre-treated with JuB (20 or 40 mg/kg) for seven days before APAP (400 mg/kg) injection. After 24 h of APAP treatment, serum, and liver tissues were collected to evaluate the therapeutic effects. To investigate whether the Nrf2-STING signaling pathway is involved in the protective effects of JuB against APAP-induced hepatotoxicity, the mice received the DMXAA (the specific STING agonist) or ML385 (the specific Nrf2 inhibitor) during the administration of JuB, and Hematoxylin-eosin staining, Real-time PCR, immunohistochemical, and western blot were performed.

RESULTS

JuB pretreatment reversed APAP-induced CYP2E1 accumulations and alleviated APAP-induced acute liver injury. Furthermore, JuB treatment significantly inhibited oxidative stress and the pro-inflammatory cytokines, as well as alleviated hepatocyte apoptosis induced by APAP. Besides, our result also demonstrated that JuB treatment upregulated the levels of total Nrf2, facilitated its nuclear translocation, upregulated the expression of HO-1 and NQO-1, and inhibited the APAP-induced STING pathway activation. Finally, we verified that the beneficial effects of JuB were weakened by DMXAA and ML385.

CONCLUSION

Our study suggested that JuB could ameliorate APAP-induced hepatic damage and verified a previously unrecognized mechanism by which JuB prevented APAP-induced hepatotoxicity through adjusting the Nrf2-STING pathway.

Dimethyl Bisphenolate Ameliorates Carbon Tetrachloride-Induced Liver Injury by Regulating Oxidative Stress-Related Genes

Liver disease accounts for millions of deaths per year all over the world due to complications from cirrhosis and liver injury. In this study, a novel compound, dimethyl bisphenolate (DMB), was synthesized to investigate its role in ameliorating carbon tetrachloride (CCl4)-induced liver injury through the regulation of oxidative stress-related genes. The structure of DMB was confirmed based on its hydrogen spectrum and mass spectrometry. DMB significantly reduced the high levels of ALT, AST, DBIL, TBIL, ALP, and LDH in a dose-dependent manner in the sera of CCl4-treated rats. The protective effects of DMB on biochemical indicators were similar to those of silymarin. The ROS fluorescence intensity increased in CCl4-treated cells but significantly weakened in DMB-treated cells compared with the controls. DMB significantly increased the content of oxidative stress-related GSH, Nrf2, and GCLC dose-dependently but reduced MDA levels in CCl4-treated cells or the liver tissues of CCl4-treated rats. Moreover, DMB treatment decreased the expression levels of P53 and Bax but increased those of Bcl2. In summary, DMB demonstrated protective effects on CCl4-induced liver injury by regulating oxidative stress-related genes.

Hepatoprotective effect of total flavonoids from Carthamus tinctorius L. leaves against carbon tetrachloride-induced chronic liver injury in mice

Carthamus tinctorius L. leaves, a waste product after Carthami flos production, are rich in flavonoids. Total flavonoids from C. tinctorius L. leaves (TFCTLL) exhibited the protective effect on acute liver injury in mice in previous studies. The aim of the present study was to evaluate the hepatoprotective effect of TFCTLL on chronic liver injury (CLI) and investigate the underlying mechanism. The chemical components of TFCTLL were identified by UPLC-Q-TOF/MS, and their migration into blood was evaluated. The protective effect of TFCTLL on CLI was evaluated by antioxidative and anti-inflammatory experiments in vitro, network pharmacology and a carbon tetrachloride (CCl4)-induced CLI mouse model. We indentified 18 chemical components in the TFCTLL samples and 4 components in plasma. TFCTLL showed significant anti-inflammatory activity and antioxidant capacity in vitro and in vivo. TFCTLL administration prominently improved the liver function and structure, decreased the mRNA expression levels of TLR2, TLR3, TLR4, NF-κB p65, IRF3, AKT1, TRIF, PI3K, MyD88, IL-1β and TNF-α and inhibited the protein expression and nuclear translocation of NF-κB p65 in mice with CLI. The molecular docking results showed that components in plasma had high binding affinity for the targets TLR4, PI3K and AKT1. Therefore, TFCTLL has a protective effect against CCl4-induced CLI, and the underlying mechanisms may be related to antioxidation, anti-inflammation and modulation of the TLRs/NF-κB and PI3K/AKT pathways.

Progress on traditional Chinese medicine in improving hepatic fibrosis through inhibiting oxidative stress

Hepatic fibrosis is a common pathological process that occurs in the development of various chronic liver diseases into cirrhosis and liver cancer, characterized by excessive deposition of the extracellular matrix. In the past, hepatic fibrosis was thought to be a static and irreversible pathological process. In recent years, with the rapid development of molecular biology and the continuous in-depth study of the liver at the microscopic level, more and more evidence has shown that hepatic fibrosis is a dynamic and reversible process. Therefore, it is particularly important to find an effective, simple, and inexpensive method for its prevention and treatment. Traditional Chinese medicine (TCM) occupies an important position in the treatment of hepatic fibrosis due to its advantages of low adverse reactions, low cost, and multi-target effectiveness. A large number of research results have shown that TCM monomers, single herbal extracts, and TCM formulas play important roles in the prevention and treatment of hepatic fibrosis. Oxidative stress (OS) is one of the key factors in the occurrence and development of hepatic fibrosis. Therefore, this article reviews the progress in the understanding of the mechanisms of TCM monomers, single herbal extracts, and TCM formulas in preventing and treating hepatic fibrosis by inhibiting OS in recent years, in order to provide a reference and basis for drug therapy of hepatic fibrosis.

Gentiopicroside ameliorates CCl4-induced liver injury in mice by regulating the PPAR-γ/Nrf2 and NF-κB/IκB signaling pathways

OBJECTIVE

This study explored the mechanisms by which gentiopicroside protects against carbon tetrachloride (CCl4)-induced liver injury.

METHODS

Male mice were randomly assigned to the control; CCl4; bifendate 100 mg/kg; or gentiopicroside 25, 50, or 100 mg/kg groups. Both vehicle and drugs were administered intragastrically for 7 days. Mice were administered CCl4 intraperitoneally 1 hour after the last drug dose. After 24 hours, we collected blood and liver samples for testing.

RESULTS

Gentiopicroside significantly reduced serum alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase activities with corresponding reductions in hepatocyte denaturation and necrosis. Gentiopicroside enhanced superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities and glutathione levels and reduced heme oxygenase 1 (HO-1) activity and malondialdehyde levels in the liver, and these effects were attributed to peroxisome proliferator-activated receptor (PPAR)-γ/nuclear factor erythroid 2-related factor 2 (Nrf2) activation. Meanwhile, gentiopicroside significantly downregulated HO-1 and upregulated SOD and GSH-Px at the mRNA level in the liver. Furthermore, gentiopicroside significantly suppressed serum tumor necrosis factor-α and interleukin-1β secretion, which was associated with the inhibition of nuclear factor-kappa B (NF-κB)/inhibitor of NF-κB (IκB).

CONCLUSIONS

Gentiopicroside ameliorated CCl4-induced liver injury in mice via the PPAR-γ/Nrf2 and NF-κB/IκB pathways.

Antioxidant Effect of a Dietary Supplement Containing Fermentative S-Acetyl-Glutathione and Silybin in Dogs with Liver Disease

Oxidative stress is often involved in liver disease progression. Liver is the primary site for the synthesis of glutathione (GSH), the major intracellular antioxidant. GSH erythrocyte concentration can decrease in case of liver damage. So, the use of food supplements with antioxidant capacity has been reported in the veterinary literature. In this case-control study, we tested a new supplement containing S-acetyl-glutathione (SAG), silybin, and other antioxidant ingredients in dogs affected by liver disease. After two weeks of supplement administration, we were able to report a significant increase in the level of erythrocyte GSH in the treated (TRT) group, nearly reaching the physiological limit at the end of the study. In addition, most of the key liver parameters are significantly reduced in the TRT group by the end of the trial. The results of this study support the effectiveness of the tested complementary feed, which may be helpful in managing dogs with liver conditions.

The effects of taraxasterol on liver fibrosis revealed by RNA sequencing

Effective treatment of liver fibrosis remains a challenging medical problem. Taraxasterol (TAR) has anti-inflammatory, anti-tumor and hepatoprotective effects. Studies have shown that TAR has good biological activity against liver injury induced by various factors. However, the anti-fibrotic effect of TAR and its mechanism are never clarified. The purpose of this study was to investigate the effects of TAR in liver fibrosis and to reveal its possible mechanism by RNA sequencing. Our results suggested that TAR attenuated CCl₄-induced hepatocyte necrosis, inflammatory infiltration and ECM deposition. TAR inhibited the levels of ALT, AST, ALP, γ-GT, LN, HA, PC III and IV-C in serum and TNF-α, IL-6, IL-1β and MDA in liver. In addition, TAR increased the activities of SOD and GSH-Px in liver. RNA sequencing analysis of liver tissues revealed that CCl₄ and TAR significantly altered 4,155 genes and 2,675 genes, respectively. TAR reversed changes in ECM-related genes. More specifically, TAR mediated the expression of genes related to the activation of the Hippo pathway, while inhibiting the expression of genes related to the activation of HIF-1α, TGF-β/Smad, and Wnt pathways. In the validation experiments, the qRT-PCR results showed that the expression levels of Yap1, Tead3, Hif1α, Vegfa, Tgfβ1, Want3a, and Ctnnb1 mRNA were consistent with the RNA sequencing results. The Western blot results showed that TAR inhibited the levels of TGF-β1 and p-Smad2. In addition, the results in vitro were consistent with those in vivo. Therefore, we concluded that TAR improved CCl₄-induced liver fibrosis by regulating Hippo, HIF-1α, TGF-β/Smad and Wnt pathways.

Ivermectin Attenuates CCl4-Induced Liver Fibrosis in Mice by Suppressing Hepatic Stellate Cell Activation

Liver fibrosis, a common liver dysfunction with high morbidity and mortality rates, is the leading cause of cirrhosis and hepatocellular carcinoma, for which there are no effective therapies. Ivermectin is an antiparasitic drug that also has been showing therapeutic actions in many other diseases, including antiviral and anticancer actions, as well as treating metabolic diseases. Herein, we evaluated the function of ivermectin in regulating liver fibrosis. Firstly, carbon tetrachloride (CCl₄)-injected Balb/c mice were used to assess the antifibrosis effects of ivermectin in vivo. Further, CFSC, a rat hepatic stellate cell (HSC) line, was used to explore the function of ivermectin in HSC activation in vitro. The in vivo data showed that ivermectin administration alleviated histopathological changes, improved liver function, reduced collagen deposition, and downregulated the expression of profibrotic genes. Mechanistically, the ivermectin treatment inhibited intrahepatic macrophage accumulation and suppressed the production of proinflammatory factors. Importantly, the ivermectin administration significantly decreased the protein levels of α-smooth muscle actin (α-SMA) both in vivo and in vitro, suggesting that the antifibrotic effects of ivermectin are mainly due to the promotion of HSC deactivation. The present study demonstrates that ivermectin may be a potential therapeutic agent for the prevention of hepatic fibrosis.

Preventive effect of salmon sperm DNA on acute carbon tetrachloride-induced liver injury in mice through Nrf2/ARE and mitochondrial apoptosis pathway

Liver injury refers to the damage of liver function, which will seriously harm the body's health if it is not prevented and treated in time. Sporadic researches have reported that ingestion of DNA has a hepatoprotective effect, but its effect and mechanism were not clarified. The purpose of this study was to explore the preventive effect and mechanism of salmon sperm DNA on acute liver injury in mice induced by carbon tetrachloride (CCl₄). Six-week-old ICR (Institute of Cancer Research) male mice were used to establish a liver injury model by injecting with 4% CCl₄, silymarin, and three different concentrations of DNA solutions were given to mice by gavage for 14 days. The histological and pathological changes in the liver were observed. The levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum and the levels of oxidative and antioxidant markers such as malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and glutathione (GSH) in liver tissue were determined. The levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay (ELISA), and hepatic oxidative stress and apoptosis-related markers were determined by western blotting. The results showed that compared with the model group, the DNA test group significantly improved the liver pathological changes and the level of liver function, regulated liver oxidative stress, reduced hepatocyte apoptosis, and decreased the levels of inflammatory factors such as TNF-α and IL-6. Compared with the silymarin group, the high dose of DNA was even more effective in preventing liver injury. In conclusion, salmon sperm DNA has a potential protective effect against acute liver injury induced by CCl₄, which is achieved by regulating the Nrf2/ARE (nuclear factor erythroid 2 (NF-E2)-related factor 2/antioxidant responsive element) oxidative stress pathway and mitochondrial apoptosis pathway.

α-Lipoic Acid Protects against Cyclosporine A-Induced Hepatic Toxicity in Rats: Effect on Oxidative Stress, Inflammation, and Apoptosis

The clinical application of cyclosporine A (CsA) as an immunosuppressive agent is limited by its organ toxicity. We aimed to evaluate the effectiveness of α-lipoic acid against CsA-induced hepatotoxicity and to delineate the underlying molecular mechanisms. Male Wistar rats (n = 24, 8 per each group) received the vehicle, CsA (25 mg/kg) and/or ALA (100 mg/kg, p.o.) for 3 weeks. Biochemical markers of liver function (serum ALT, AST, ALP < GGT), oxidative stress (MDA, TAC, SOD, GSH, Nrf2/HO-1), inflammation (NF-κB, CD68, iNOS, NO, COX-2), and apoptosis (caspase-3) were assessed in serum and tissue. Liver histological analysis using H&E and Sirius red was performed. The development of liver injury in CsA-treated animals was indicated by elevated levels of liver enzymes, oxidants/antioxidants imbalance, inflammatory cells infiltration, up-regulated expression of inflammatory mediators, and apoptosis. These changes were associated with altered architecture of hepatic cells and fibrous connective tissue. ALA co-administration protected against CsA-induced liver damage and ameliorated biochemical changes and cellular injury. In conclusion, ALA demonstrated hepatoprotective potential against CsA-induced liver injury through combating oxidative stress, inflammation, and apoptosis, highlighting ALA as a valuable adjunct to CsA therapy.