Inhibitory effect of tannin in green tea on the proliferation of mesangial cells.

The effect of green tea tannin on the proliferation of mesangial cells was determined in terms of [3H]thymidine uptake. When green tea tannin was added to the medium of mesangial cell cultures, it suppressed the proliferation of mesangial cells markedly. In particular, (-)-epigallocatechin 3-O-gallate, the predominant component of the green tea tannin mixture, exerted an inhibitory effect at a relatively low concentration, suggesting a direct corroboration of the renal effects.