The protection of Thymus vulgaris leaves alcoholic extract against hepatotoxicity of alcohol in rats

Abstract

Objective: To investigate the protective effect of Thymus vulgaris (T. vulgaris) leaves 70% alcoholic extract against alcohol-mediate hepatotoxicity rats.

Methods: The protective effect of T. vulgaris extract was investigated at dose of 500 mg/kg/day (as 0.1 of LD₅₀) orally against alcohol-mediate hepatotoxicity using adult male Wister albino rats during 21 days. Protective effect of T. vulgaris extract was evaluated comparing with silymarin standard drug at recommended dose (25 mg/kg/day) orally for 21 days. Serum liver and kidney functions, serum lipid profile, liver antioxidant enzymes activities, liver glutathione concentration (GSH), liver oxidative parameters and histopathological study of liver and kidney were estimated to find out protective effect of T. vulgaris extract.

Results: Alcohol-mediate hepatotoxicity rats (alcohol-control) showed hepatocytes distortion represented as marked increment on liver biomarkers; alkaline phosphatase (ALP), aspartate transaminase (AST) and alanine transaminase (ALT) activities, as well as pronounced reduction on total protein and its fractions albumin and globulin production corresponding to normal ranges. Oxidative stress status was appeared on alcohol-control evident as significant depletion on GSH concentration, antioxidant enzymes activities; catalase (CAT), superoxide dismutase (SOD), glutathione reductase (GR), glutathione- S- transferase (GST) and glutathione peroxidase (GPx) recorded significant dwindling, concurrence with significant augmentation on oxidative stress parameters; malondyaldehyde (MDA) and hydrogen peroxide (H₂O₂) concentrations with respect to normal values. Serum lipid profile was affected by alcohol administration, total cholesterol (TC) and low density lipoprotein cholesterol (LDL-C) were significantly reduced, meanwhile high density lipoprotein cholesterol (HDL-C) was raised comparing to normal ranges. Co-administration of T. vulgaris extract with alcohol showed protective effect on hepatocytes manifested as remarkable minimizing on ALP, AST and ALT activities and marked increment on total protein, albumin and globulin production compared to alcohol-control. Amelioration was achieved on oxidative stress status on rats co-administrated T. vulgaris extract with alcohol. Accordingly, antioxidant enzymes activities; CAT, SOD, GR, GST and GPx were significantly magnified, while oxidative stress parameters; MDA and H₂O₂ concentration were significantly lessened corresponding to alcohol-control. Also, lipid profile was markedly improved and risk ratio was lowered by T. vulgaris extract co-administrated in comparison with alcohol-control. All these obvious results were confirmed by histopathological examination, which illustrated that extract showed normalization of degenerated and fibrotic liver tissue as of alcohol-control.

Conclusion: T. vulgaris extract protected hepatocytes from damaging by alcohol reflecting improvement on liver performance and inhibition of oxidative stress status of liver. T. vulgaris extract appeared hepatoprotective, hypolipidemic and antioxidant activities on alcohol-mediate hepatotoxicity rats compared to silymarin.

Keywords: Alcohol-mediate hepatotoxicity; Antioxidants enzymes activities; Histopathology; Oxidative stress; Polyphenols; Thymus vulgaris.