Antioxidants activity and cholesterol regulation effect of Caralluma flava N.E.Br extract in HepG2 cells

Abstract

Herbal medicine has a long-standing history in many locations in Yemen and continue to provide useful and applicable tools for treating ailments. The objectives of the present study are to investigate antioxidant activity and cholesterol regulatory effect of Caralluma flava N.E.Br methanolic extract (CFM) through chemical and molecular approaches. CFM afforded the yield of 18 % (w/w) through methanolic extraction and contained considerable amount of phenolic and flavonoid compounds (9.22 ± 1.4 mg/g) and 3.35 ± 0.16 mg/g respectively). Antioxidant activity assays revealed that CFM are effective antioxidant with 76.8% DPPH scavenging activity bleaching inhibitory activity. Result from s-carotene–linoleic acid assay shows that CFM efficiently retarded the oxidation of linoleic acid in the reaction system compared to control. CFM regulate the expression of cholesterol metabolism genes in HepG2 cells in a dose-dependent manner. The low-density lipoprotein receptor (LDLR) mRNA level was significantly up-regulated by 1.3, 2.4 and 3.2 fold compared to control cells. The mRNA level of 3-Hydroxy-3-Methylglutaryl-CoA Reductase (HMGCOA) was significantly suppressed by 12, 30 and 50% in a dose dependent manner compared to the control cells treated with 20, 50 and 100 µg/ml of CFM respectively. Apolipoprotein A-1 (Apo A-1) gene was up-regulated by 1.7 and 2.2 fold and apolipoprotein B100 (Apo B100) gene was suppressed by 11% and 24% in HepG2 cells treated with 50 and 100 µg/ml of CFM respectively, compared to control cells.  In conclusion, CFM is a potential cardioprotector through enhancement of cholesterol regulation and exertion of antioxidant activity.