Possible Interaction: Neuropeptide Y and Tretinoin

“Interestingly, some agents, like retinoic acid , have been shown to modulate the expression of both NPY and NPY-Rs in the same direction, thus providing a fine mechanism for the tuning of the system.”

“Moreover, RA treatment for 6 days, but not for 24 h, resulted in a marked stimulation of proNPY processing to mature NPY.”

“The NPY content in cell extracts and the NPY secreted and accumulated in the culture medium were also reduced by exposure to 10 microM RA at 12 and 24 h and at 6 days.”

“These observations suggest that the expression of NPY in SH-SY5Y human neuroblastoma cells is negatively regulated by RA at the level of gene expression, probably by mechanisms involving the interaction of activated RARs with transcription factors (such as AP-1).”

“Treatment with 10 microM RA induced a marked decrease in NPY gene expression after as little as 3-6 h of incubation and resulted in its almost complete suppression at 12-24 h and after a 6-day differentiating treatment.”

“ NPY stimulated growth was significantly attenuated after RA treatment, possibly as a result of decreased NPY receptor expression.”