Mannose antagonizes GSDME-mediated pyroptosis through AMPK activated by metabolite GlcNAc-6P

Pyroptosis is a type of regulated cell death executed by gasdermin family members. However, how gasdermin-mediated Pyroptosis is negatively regulated remains unclear. Here, we demonstrate that mannose, a hexose, inhibits GSDME-mediated Pyroptosis by activating AMP-activated protein kinase (AMPK). Mechanistically, mannose metabolism in the hexosamine biosynthetic pathway increases levels of the metabolite N-acetylglucosamine-6-phosphate (GlcNAc-6P), which binds AMPK to facilitate AMPK phosphorylation by LKB1. Activated AMPK then phosphorylates GSDME at Thr6, which leads to blockade of caspase-3-induced GSDME cleavage, thereby repressing Pyroptosis. The regulatory role of AMPK-mediated GSDME phosphorylation was further confirmed in AMPK knockout and GSDME^T6E or GSDME^T6A knock-in mice. In mouse primary Cancer Models, mannose administration suppressed Pyroptosis in small intestine and kidney to alleviate cisplatin- or oxaliplatin-induced tissue toxicity without impairing antitumor effects. The protective effect of mannose was also verified in a small group of patients with gastrointestinal Cancer who received normal chemotherapy. Our study reveals a novel mechanism whereby mannose antagonizes GSDME-mediated Pyroptosis through GlcNAc-6P-mediated activation of AMPK, and suggests the utility of mannose supplementation in alleviating chemotherapy-induced side effects in clinic applications.