Regulation of pyroptosis by sodium butyrate supplementation mitigates cold stress-induced intestinal damage in Danzhou chicken

Abstract

Cold stress poses a significant threat to intestinal health in young broilers, contributing to economic losses and welfare concerns; however, the underlying mechanisms and effective interventions remain unclear. To investigate these aspects, this study examined the effects of cold stress on intestinal barrier integrity and explored the protective potential of sodium butyrate supplementation. Forty-five-day-old broilers were randomly assigned to either a control group (CON, thermoneutral at 30 ± 1 °C) or a cold stress group (CS, exposed to 10 ± 1 °C) for 48 h. Intestinal tissues were analyzed for histopathology, tight junction protein expression, oxidative stress markers (CAT, MDA, T-SOD, T-AOC), inflammatory cytokines (LITAF, TNF-α, IL-1β, IL-6, IL-8, IL-10), and pyroptosis-related indicators (Caspase-1, NLRP3). Cold stress significantly disrupted intestinal barrier function, as evidenced by histopathological damage and altered expression of tight junction proteins. The CS group exhibited increased oxidative stress, elevated inflammatory cytokines, and enhanced pyroptosis activation. Given sodium butyrate's role as a crucial energy source for intestinal cells and its reported anti-inflammatory properties, we hypothesized it could mitigate cold stress-induced damage. To test this, an in vitro model using chicken macrophage HD11 cells subjected to cold stress was treated with sodium butyrate (1 mM). Sodium butyrate effectively alleviated oxidative stress and suppressed pyroptosis in cold-stressed HD11 cells. Mechanistic analysis revealed that this protection was associated with the inhibition of the NLRP3/Caspase-1 signaling pathway. These findings demonstrate that sodium butyrate supplementation attenuates cold stress-induced intestinal damage in broilers, likely through mitigating oxidative stress and inhibiting NLRP3 inflammasome-mediated pyroptosis, highlighting its potential as a protective dietary intervention.