Effect of cholestin on toxicity of vitamin A in rats

Effects of IC50 dose of retinol on metabolomics of RAW264.7 cells

Vitamin A is one of the most multifunctional vitamins in normal human physiology and is involved in several basic physiological processes from embryonic development to adulthood, such as embryogenesis, vision, immunity, cell differentiation, and proliferation. In this study, we conducted ¹ H- NMR to evaluate the metabolomic changes in RAW264.7 cells after treatment with retinol at an IC₅₀ dose to identify its effects on the differential metabolites and main metabolic pathways. Our results showed that the IC₅₀ dose (140 μM) of retinol affected the metabolism of RAW264.7 cells, with a total of 22 differential metabolites identified via ¹ H-NMR, including amino acids, sugars, organic acids, glutathione, glycerin, and creatine. Additionally, multiple metabolic pathways were affected by retinol treatment, including downregulation of amino acid biosynthesis, protein synthesis, and pyruvate metabolism. We speculate that the cytotoxicity of retinol at the IC₅₀ dose is attributed to mitochondrial dysfunction as a result of oxidative stress or lipid peroxidation. PRACTICAL APPLICATIONS: With the general improvement of people's living standards, people use dietary supplements to improve the level of retinol to prevent non-specific diseases. But there are more and more cases of acute or chronic poisoning caused by excessive intake of vitamin A. Therefore, it is necessary to study the toxicity of vitamin A, and more attention should be paid to the excessive intake of vitamin A. From the perspective of metabolomics, this experiment studies the adverse effects of high dose retinol through the changes of metabolites and metabolic pathways at the cellular level. This study will assist further analyses of the toxic mechanism of excessive retinol as fortified foods and nutrient supplementation.

Protective effects of Cholestin on ethanol induced oxidative stress in rats

BACKGROUND

Male Wistar rats were divided into seven groups as follows: group A, basal diet; group B, basal diet with Cholestin at 0.1667 g kg⁻¹ body weight (BW); groups C-F, oral feeding of ethanol at 7.9 g kg⁻¹ BW; groups D-F, Cholestin in diet at 0.1667, 0.3333 and 0.5 g kg⁻¹ BW respectively; group G, silymarin in diet at 200 mg kg⁻¹ BW.

RESULTS

The results showed that treatment with Cholestin for 8 weeks reduced the impact of ethanol toxicity on serum markers of liver damage: aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP). The antioxidant system was significantly enhanced: plasma and hepatic thiobarbituric acid-reactive substance (TBARS) levels were lowered while hepatic superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px), ethanol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) activities and non-enzymatic antioxidants (vitamin E, vitamin C and GSH) were elevated.

CONCLUSION

Cholestin shows a protective effect against hepatotoxicity indices in ethanol-fed rats comparable to that of silymarin, as supported by the evaluation of liver histopathology. The data suggest that Cholestin exerts its hepatoprotective effect by decreasing lipid peroxidation and improving antioxidants status, thus proving itself as an effective antioxidant in ethanol-induced oxidative damage in rats.