IL6 and Alzheimer disease: Since the cellular senescence of neurons is tightly connected with AD pathogenesis as well as other neurodegenerative diseases (27, 28), we next examined whether PGDHC or Pg-LPS elevated expression of some senescence-associated secretory phenotype (SASP) factors, including β-galactosidase, cathepsin B (CtsB) cysteine, and TNF-α and IL-6 pro-inflammatory cytokines in SH-SY5Y cells in vitro.