A Debate Over Callous deacetylase inhibitor Dinaciclib r-Systems

To our know-how, this is the rst report to evaluate the effect of danshen extract on CYP3A activity in vivo by administering midazolam as a CYP3A probe to human volunteers.

Within this study, administration of several doses of danshen tablets induced a signicant enhance in apparent oral clearance, a corresponding signicant decline in Cmax from 113. 98 ng ml1? 72. 50 ng ml1 plus a signicant decline in AUC from 353. 62 ng ml1 h to 254. 96 ng ml1 h. The results suggested that chronic administration deacetylase inhibitor of danshen tablets may induce the CYP3A enzyme in vivo. The t1/2 of midazolam Dinaciclib and 1 hydroxymidazolam and the Cmax and AUC ratio of midazolam to 1 hydroxymidazolam were not signicantly affected by 14 days of danshen tablet administration, suggesting the induction of CYP3A was mainly in the wall of the small intestine. Our ndings suggest that the Cmax of danshensu was 34. 92 5. 13 ng ml1, and concentrations of tanshinone IIA, tanshinone I and cryptotanshinone were below 1 ng ml1 following administration of four danshen tablets.

Thus low oral bioavailability was also attributed to the rst pass effect. At an estimated gut concentration of approximately 10 M, the concentration of cryptotanshinone and tanshinone IIA could induce the intestinal CYP3A4 enzymes. Therefore, the results of this study could be due to the Dinaciclib induction of intestinal CYP3A4 by a higher concentration of cryptotanshinone and tanshinone IIA in the intestine. The xenobiotic mediated induction of the human CYP3A gene is known to be regulated by PXR, CAR, GR as well as other receptors. PXR is a key regulator of xenobiotic inducible CYP3A gene expression. PXR and CAR have the potential to cross regulate CYP3A gene expres sion. Another nuclear receptor GR can be activated to increase the expression of PXR, CAR and retinoid X receptor, which in turn function as transcriptional regulators of the CYP3A gene.

Furthermore, P gp and CYP3A4 have considerable overlap in inducers in vitro and share common regulatory mechanisms. P gp can be induced by tanshinone IIA and cryptotanshinone.