Induction of neutral endopeptidase and angiotensin-converting enzyme activity of SK-N-SH cells in vitro by quercetin and resveratrol.

Quercetin and resveratrol are weak inhibitors of neutral endopeptidase (NEP) and angiotensin-converting enzyme (ACE) activity of the neuroblastoma cell line SK-N-SH. The long term incubation of the cells for 4 days with quercetin, resveratrol and a combination of both substances in concentrations lower than necessary for inhibition of NEP and ACE activity induced the cellular enzyme activity of NEP and ACE associated with an inhibition of cellular proliferation. The long term treatment of neuroblastoma cells with quercetin and resveratrol enhanced the differentiation state of the cells. Taking into account the significance of NEP and ACE for the degradation of amyloid beta peptides, the effect of quercetin and resveratrol as constituents of red wine for a neuroprotective activity is discussed.