[Inhibition of protein kinase C by stilbenoids].
The effect of 15 stilbenoids on protein kinase C (PKC) was studied in order to search for naturally occurring PKC inhibitors. All these compounds were isolated from Chinese medicines. Three oligomeric stilbenes from Caragana sinica, alpha-viniferin, kobophenol A and miyabenol C, were shown to intensely inhibit the activity of partially purified rat brain PKC with IC50 values of 62.5, 52.0, and 27.5 mumol.L-1, respectively. Kinetic analyses revealed that that inhibition was noncompetitive. The other compounds also showed the effect. Monomer stilbenes exhibited PKC inhibitory activity at higher mumol.L-1 concentrations than oligomeric stilbenes. Whenever they are methylated or acetylated perfectly, the inhibition weakens or disappears.
Xu
G
G
Department of Biochemistry, School of Basic Medical Sciences, Shanghai Medical University.
Zhang
L P
LP
Chen
L F
LF
Hu
C Q
CQ
D000818:Animals; D001923:Brain Chemistry; D004365:Drugs, Chinese Herbal / Q000737:chemistry; D008297:Male; D011493:Protein Kinase C / Q000037:antagonists & inhibitors* / Q000302:isolation & purification / Q000378:metabolism; D051381:Rats; D013267:Stilbenes / Q000302:isolation & purification / Q000494:pharmacology*
D004365:Drugs, Chinese Herbal; D013267:Stilbenes; D011493:Protein Kinase C