Adipose stem cells enhance myoblast proliferation via acetylcholine and ERK1/2 signaling

Introduction We investigated the interaction between adipose tissue derived stem cells (ASCs) and myoblasts in co-culture experiments. Methods Specific inductive media were used to differentiate ASCs in vitro into a Schwann cell-like phenotype (dASCs), and subsequently the expression of acetylcholine (ACh) related machinery was determined. Furthermore, the expression of muscarinic ACh receptors (mAChRs) was examined in denervated rat gastrocnemius muscles. Results In contrast to undifferentiated ASCs, dASCs expressed more choline acetyltransferase (ChAT) and vesicular acetylcholine transporter (VAChT). When co-cultured with myoblasts, dASCs enhanced the proliferation rate, as did ACh administration alone. Western blotting and pharmacological inhibitor studies showed that p-ERK1/2 signaling mediated these effects. Additionally, denervated muscle showed higher expression of mAChRs than control muscle. Discussion These results suggest that dASCs promote proliferation of myoblasts through paracrine secretion of ACh, which could explain some of their regenerative capacity in vivo. This article is protected by copyright. All rights reserved.