Metabolic transformation of sesamol and ex vivo effect on 2,2'-azo-bis(2-amidinopropane)dihydrochloride-induced hemolysis.

Sesamol (3,4-methylenedioxyphenol), a phenolic constituent in roasted sesame, was reported to exhibit various beneficial activities. To understand the metabolic transformation of sesamol in vivo, rats were given sesamol intravenously and orally. The blood samples were withdrawn via cardiopuncture at specific time points. The serum samples were assayed by high-performance liquid chromatography method before and after hydrolysis with sulfatase and beta-glucuronidase. Our results indicated that following either intravenous or oral administration, sesamol declined rapidly and the sulfate/glucuronide of sesamol emerged instantaneously. The peak serum concentration and systemic exposure of sesamol were markedly lower than sesamol sulfate/glucuronide. Ex vivo evaluation revealed that sesamol exerted profoundly higher capability against 2,2'-azo-bis(2-amidinopropane)dihydrochloride-induced hemolysis than the serum metabolites. In conclusion, sulfate and glucuronide of sesamol were the principle metabolites of sesamol in the bloodstream of rats. The conjugated metabolites of sesamol warrant more bioactivity investigations to understand the in vivo effect of sesamol.