Oxidative Stress in Alcoholic Liver Disease

Polydatin: A Critical Promising Natural Agent for Liver Protection via Antioxidative Stress

Polydatin, one of the natural active small molecules, was commonly applied in protecting and treating liver disorders in preclinical studies. Oxidative stress plays vital roles in liver injury caused by various factors, such as alcohol, viral infections, dietary components, drugs, and other chemical reagents. It is reported that oxidative stress might be one of the main reasons in the progressive development of alcohol liver diseases (ALDs), nonalcoholic liver diseases (NAFLDs), liver injury, fibrosis, hepatic failure (HF), and hepatocellular carcinoma (HCC). In this paper, we comprehensively summarized the pharmacological effects and potential molecular mechanisms of polydatin for protecting and treating liver disorders via regulation of oxidative stress. According to the previous studies, polydatin is a versatile natural compound and exerts significantly protective and curative effects on oxidative stress-associated liver diseases via various molecular mechanisms, including amelioration of liver function and insulin resistance, inhibition of proinflammatory cytokines, lipid accumulation, endoplasmic reticulum stress and autophagy, regulation of PI3K/Akt/mTOR, and activation of hepatic stellate cells (HSCs), as well as increase of antioxidant enzymes (such as catalase (CAT), glutathione peroxidase (GPx), glutathione (GSH), superoxide dismutase (SOD), glutathione reductase (GR), and heme oxygenase-1 (HO-1)). In addition, polydatin acts as a free radical scavenger against reactive oxygen species (ROS) by its phenolic and ethylenic bond structure. However, further clinical investigations are still needed to explore the comprehensive molecular mechanisms and confirm the clinical treatment effect of polydatin in liver diseases related to regulation of oxidative stress.

Gentiopicroside prevents alcoholic liver damage by improving mitochondrial dysfunction in the rat model

Gentianae Radix et Rhizoma is a medical plant that is widely cultivated in China, North Korea, Japan, and Russia, and gentiopicroside is one of its major active compounds. In this study, the hepatoprotective activity of gentiopicroside on rats with alcoholic liver damage (ALD) was evaluated using the transaminase and blood lipid levels and antioxidant capacity. The potential mechanism of hepatoprotective effect of gentiopicroside was evaluated by mitochondrial function detection, gas chromatography-mass spectrometry (GC-MS) metabolomic analysis, and anti-apoptosis analysis. Results showed that the gentiopicroside exhibited good hepatoprotective activity on rats with ALD by decreasing the transaminase levels, regulating the blood lipid levels, and increasing the antioxidant capacity. The potential mechanisms were related to regulating mitochondrial dysfunction by recovering mitochondrial membrane potential level, adenosine triphosphate concentration, activities of key enzymes in tricarboxylic acid cycle, and activities of complex I-V, regulating micromolecular metabolism and anti-apoptosis. These findings supported the further exploration of Gentianae Radix et Rhizoma as effective phytotherapy to prevent and treat ALD.

The effect of silymarin on liver enzymes in patients taking isotretinoin: A randomized clinical trial

The aim of the present study was to investigate the effect of silymarin (Livergol) on liver enzymes in patients taking isotretinoin (Roaccutane). In this double-blind clinical trial, 74 patients with acne and taking isotretinoin were randomly assigned into intervention (N = 37) and control (N = 37) groups. The intervention group received a 140 mg Livergol capsule per day for 30 days. The control group received a starch-containing capsule as a placebo once a day for 30 days. Liver enzyme levels were measured before and after the intervention. The data were analyzed using chi-square test, Independent t test, paired sample t test and analysis of covariance (ANCOVA). The results showed no statistically significant difference between the intervention and control groups at the beginning of study in levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) (p > .05). At the end of the study, a statistically significant difference was observed between the two groups in levels of AST and ALT (p < .05). Livergol prevented liver enzymes from increasing, so it can be used as an effective, low-cost, and low-complication treatment for the problem of increased levels of liver enzymes following the use of isotretinoin.

The role of immune mechanisms in alcoholic and nonalcoholic steatohepatitis: a 2015 update

So far, innate immune mechanisms have been recognized as the main responsible for the evolution of both alcoholic steatohepatitis (ASH) and nonalcoholic steatohepatitis (NASH). However, increasing evidence points toward the possible role of adaptive immune responses, as an additional factor in promoting hepatic inflammation in steatohepatitis. In this article, we discuss recent data involving circulating antibodies and lymphocyte-mediated responses in sustaining the progression of ASH and NASH to fibrosis, as well as the possible mechanisms implicated in favoring the onset of adaptive immunity in the setting of steatohepatitis.