Butyrate attenuates sympathetic activation in rats with chronic heart failure by inhibiting microglial inflammation in the paraventricular nucleus

• Butyrate supplementation significantly improves cardiac function and reduces sympathetic activation in rats with chronic heart failure. • The protective effects of butyrate are mediated by enhancing intestinal barrier integrity and reducing systemic inflammation. • Butyrate attenuates microglial inflammation and M1 polarization in the paraventricular nucleus, decreasing NMDA receptor expression. • These findings suggest that gut microbiota-derived butyrate may serve as a potential therapeutic target for heart failure management.