Capsaicin Impairs Proliferation of Neural Progenitor Cells and Hippocampal Neurogenesis in Young Mice

Abstract

Capsaicin (N-vanillyl–8–methyl–1–nonenamide) is a major pungent ingredient in hot peppers and induces apoptosis in malignant carcinoma cell lines. However, the adverse effects of capsaicin on neuronal development have not been fully explored. The aim of this study was to determine whether capsaicin affected murine-derived cerebellar multi-potent neural progenitor cells (NPC) or adult hippocampal neurogenesis in vivo. Capsaicin dose-dependently suppressed NPC proliferation, and higher concentrations were cytotoxic. Capsaicin decreased the activation of extracellular signal-regulated kinases (ERK) without markedly affecting p38 kinases. Capsaicin reduced the number of newly generated cells in the dentate gyrus of the hippocampus but did not significantly alter learning and memory performance in young adult mice. Interestingly, capsaicin decreased ERK activation in the hippocampus, suggesting that reduced ERK signaling may be involved in the capsaicin-mediated regulation of hippocampal neurogenesis.

This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (no. 2009–0067608). The authors thank Dr. C. Cepko at Harvard University, Boston, for kindly providing the C17.2 cell line. We are thankful to the Aging Tissue Bank for providing aging research resources.

Notes

Kyoung Hye Kong and Hyun Kyu Kim contributed equally to this work