Xu G, Zhang L P, Chen L F, Hu C Q
Department of Biochemistry, School of Basic Medical Sciences, Shanghai Medical University.
Yao Xue Xue Bao. 1994;29(11):818-22.
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.
