Neuronostatin regulates proliferation and differentiation of rat brown primary preadipocytes

Neuronostatin suppresses the differentiation of white preadipocytes. However, the role of neuronostatin in brown adipose tissue remains elusive. Therefore, we investigated the impact of neuronostatin on the proliferation and differentiation of isolated rat brown preadipocytes. We report that neuronostatin and its receptor (GPR107) are synthesized in brown preadipocytes and brown adipose tissue. Furthermore, neuronostatin promotes the replication of brown preadipocytes via the AKT pathway. Notably, neuronostatin suppresses the expression of markers associated with brown adipogenesis (PGC‐1α, PPARγ, PRDM16, and UCP1) and reduces cellular mitochondria content. Moreover, neuronostatin impedes the differentiation of preadipocytes by activating the JNK signaling pathway. These effects were not mimicked by somatostatin. Our results suggest that neuronostatin is involved in regulating brown adipogenesis. Neuronostatin stimulates the proliferation of brown preadipocytes via the AKT pathway. Moreover, neuronostatin activates the JNK pathway, which is accompanied by suppression of the expression of markers associated with brown adipogenesis (PGC‐1α, PPARγ, PRDM16, and UCP1). Therefore, neuronostatin stimulates brown preadipocyte proliferation but suppresses differentiation of brown preadipocytes into adipocytes.