Mar 9 10 9:06 AM

Tags : :

Does alpha-asarone actually inhibit CYP3A4 and CYP2D6 in humans? Or is this all in vitro nonsense?

Here's a clip from a vendor selling alpha-asarone:

α-Asarone is a component of certain essential oils used in traditional Chinese herbal medicine. Although carcinogenic, α-asarone has been shown to be neuroprotective and radioprotective in mice when given at 50 mg/kg. It also lowers serum cholesterol in rats, specifically reducing LDL-cholesterol levels and cholesterol saturation index, by directly inhibiting HMG-CoA reductase (IC50 = 3 mM). α-Asarone also directly interacts with and inhibits certain isoforms of cytochrome P450 (IC50 = 55.2 and 65.2 μg/ml for CYP2D6 and CYP3A4, respectively).

Also look here: http://www.ncbi.nlm.nih.gov/pubmed/21062640

The present study was aimed to investigate the possible interaction of the standardized extract of Acorus calamus (AC) with Cytochrome P450 enzyme, quantitative determination of the α-asarone in the AC rhizome was performed by RP-HPLC method. In vitro interaction of the plant extract was evaluated by CYP450-carbon monoxide complex (CYP450-CO) assay. Effect on individual isoforms such as CYP3A4 and CYP2D6 isozymes were analyzed through fluorescence product formation and respective IC(50) values were determined. CYP450-CO assay showed moderate interaction potential. Extract showed higher IC(50) values (46.84±1.83-32.99±2.21 μg/ml) comparing to the standard inhibitors and lower IC(50) value than α-asarone (65.16±2.37-42.15±2.45 μg/ml).

I searched for days for proof that asarone inhibits CYP3A4 and CYP2D6 in humans and I could not find any study showing that it does.

Is there such a study in humans?