Abstract
Piperine (CAS no: 94-62-2), an alkaloid obtained from Piper nigrum and P. longum is a known inhibitor of various enzymes (CYP isozymes) responsible for biotransformation
of drugs. By inhibiting the metabolism of drugs, piperine improves the bioavailability
of drugs. In the present study piperine (10 mg/kg) significantly increased the dose-dependent
anti-hyperglycemic activity of nateglinide (CAS no: 105816-04-4) as evaluated by glucose
challenged and alloxan-induced diabetic models, when it was administered with nateglinide.
Nateglinide plasma concentrations were also increased, when administered with piperine.
The synergistic anti-hyperglycemic activity of nateglinide when administered with
piperine can be attributed to increased plasma concentration of nateglinide. The results
of this study demonstrate that piperine could be used as a potential bioenhancer along
with nateglinide.
Key words
piperine - nateglinide - antihyperglycemic - rats - pharmacokinetics
