Inflammation-Modulated Metabolic Reprogramming Is Required for DUOX-Dependent Gut Immunity in Drosophila

Abstract

DUOX, a member of the NADPH oxidase family, acts as the first line of defense against enteric pathogens by producing microbicidal reactive oxygen species. DUOX is activated upon enteric infection, but the mechanisms regulating DUOX activity remain incompletely understood. Using Drosophila genetic tools, we show that enteric infection results in ‘‘pro-catabolic’’ signaling that initiates metabolic reprogramming of enterocytes toward lipid catabolism, which ultimately governs DUOX homeostasis. Infection induces signaling cascades involving TRAF3 and kinases AMPK and WTS, which regulate TOR kinase to control the balance of lipogenesis versus lipolysis. Enhancing lipogenesis blocksDUOXactivity, whereas stimulating lipolysis viaATG1-dependent lipophagy is required for DUOX activation. Drosophila with altered activity inTRAF3-AMPK/WTS-ATG1pathwaycomponents exhibit abolished infection-induced lipolysis, reduced DUOX activation, and enhanced susceptibility to enteric infection. Thus, this work uncovers signaling cascades governing inflammation-induced metabolic reprogramming and provides insight into the pathophysiology of immune-metabolic interactions in the microbe-laden gut epithelia. (c) 2018 Elsevier Inc.