Dihydrotanshinone I

Fourteen constituents were isolated from the roots of Salvia miltiorrhiza f. alba. Two of them were new compounds and were named 1,2,15,16-tetrahydrotanshiquinone (I) and tanshinaldehyde (II). The others were identified as Ro-090680 (III), dihydroisotanshone I (IV), danshexinkun B (V), miltirone (VI), nortanshinone (VII), hydroxytanshinone II-A (VIII), tanshinone I (IX), dihydrotanshinone I (X), tanshinone II-A (XI), cryptotanshinone (XII), methylenetanshiquinone (XIII), methyltanshinonate (XIV), I and III showed inhibitory activity against P388 Leukemia cell in vitro. III was reported to be a potent inhibitor of rabbit platelet aggregation induced by collagen.

In the course of a screening of plant extracts for potential CNS and anti-inflammatory activities, a dichloromethane extract of Salvia miltiorrhiza showed a pronounced inhibitory effect on recombinant monoamine oxidase A (MAO A) and on inducible NO synthase (iNOS) induction in Raw 267.4 cells. With the aid of HPLC-based profiling techniques, activities could be linked, to a significant extent, to peaks of tanshinone-type diterpenoids, four of which were subsequently isolated. The IC50 of the most active compound, 15,16-dihydrotanshinone I, on human recombinant MAO A was at 23 microM, and 2.4 microM on lipopolysaccharide-mediated iNOS induction in Raw 267.4 cells.

Salvia miltiorrhiza (S. miltiorrhiza) and Salvia castanea Diels f. tomentosa (S. castanea) are both used for treatment of cardiovascular diseases. They have the same bioactive compound tanshinones, but whose contents are hugely different. This study illustrated diverse responses of tanshinone biosynthesis to yeast extract (YE) and Ag;+; in hairy roots of the two species. YE enhanced both the growth and tanshinone biosynthesis of two hairy roots, and contributed more to tanshinone accumulation in S. castanea than that in S. miltiorrhiza. Genes encoding 1-deoxy-d-xylulose 5-phosphate synthase (DXS2), geranylgeranyl diphosphatesynthase (GGPPS1), copalyl diphosphate synthase (CPS1), and two cytochromes P450 (CYP76AH1 and CYP76AH3) were also more responsive to YE in S. castanea than those in S. miltiorrhiza. Accumulations of dihydrotanshinone I and tanshinone I, and most biosynthetic genes in S. miltiorrhiza were more responsive to Ag;+; than those in S. castanea. Accumulations of dihydrotanshinone I and cryptotanshinone were more responsive to YE, while tanshinone IIA accumulation was more responsive to Ag;+; in S. miltiorrhiza. However, accumulations of other four tanshinones and related genes in S.