Preclinical pharmacokinetics and herb-drug interaction studies of atorvastatin co-administered with the herbal slimming products

Abstract

Herbal slimming products (HSPs) contain multiple herbs used in weight loss. Phytoconstituents of several plant extracts show the inhibitory effects on the drug-metabolizing enzymes causing interaction when taken with other drugs. Atorvastatin (ATS) is used in the treatment of hyperlipidemia. This study aimed to investigate the effect of HSPs on the pharmacokinetics and pharmacodynamics of ATS. ATS (10 mg/Kg) was administered alone or in combination with HSP1 (200 mg/Kg)/ HSP2 (165 mg/Kg) orally in the SD rats for pharmacokinetics study. Hyperlipidemia was induced in Golden Syrian Hamster by feeding HFD (60% kcal). Furthermore, biochemical levels in serum, ROS, gene expression and lipid accumulation levels were examined in hamster liver tissue. HSPs have significantly enhanced the permeability and inhibited the metabolism of ATS by inhibiting the CYP3A4 isoenzyme confirmed by in vitro assay. Co-administration of HSPs with ATS enhanced the relative bioavailability of ATS.Concomitant administration of HSPs with ATS has significantly reduced the fat content, inflammatory cytokines, TG, VLDL, LDL levels, tissue MDA level, HMGCR and SREBP1c mRNA expression levels, lipid accumulation as well as collagen content and has increased the serum HDL level as well as tissue SOD, CAT, GHS and mRNA expression levels of LXRα and CYP7A1. The aforementioned outcomes indicated that coadministration of HSPs with ATS may lead to herb-drug interaction. Therefore, precaution should be taken and dose adjustment is required when administered simultaneously.