Fig. 2

MSC-derived IL-6 suppresses the autophagy pathway in injured hippocampal neurons in Alzheimer’s disease through the downregulation of the AMPK (mitogen-activated protein kinase) signaling pathway. The AMPK signaling pathway is a downstream target of IL-6. IL-6 binds to the gp130-IL-6R receptor complex and induces a downregulation in the AMPK signaling pathway. IL-6 can induce mTOR, a pivotal factor in the autophagic signaling pathway, in an AMPK-dependent and STAT3-independent manner, leading to decreasing autophagy-associated proteins like Beclin 1 and LC3 II. The images depicted in the figure are designed by authors