Gut-muscle axis improves meat quality by regulating energy metabolism

Meat quality in pigs is of notable relevance for human health and the economic development of the livestock industry. In recent years, the establishment of the gut-muscle axis concept has underscored the key role of gut microbiota and their host interactions in regulating skeletal muscle physiology, offering a fresh perspective for elucidating the mechanisms underlying meat quality formation. This review collates the impact of the gut-muscle axis on skeletal muscle energy metabolism and its role in governing the molecular mechanisms that determine pork quality, with a focus on two key intrinsic characteristics of muscle: intramuscular fat (IMF) deposition and muscle fiber type composition. We systematically elaborate on how gut microbiota, their metabolites (short-chain fatty acids, SCFAs; branched-chain amino acids, BCAAs; bile acids, BAs), alongside intestinal barrier function and neuroendocrine pathways, mediate these regulatory effects. On this basis, the review also explores the sustained influence of the gut-muscle axis on post-mortem muscle biological processes, outlining potential pathways through which the axis contributes to improved pork eating quality and delayed muscle deterioration-achieved by mitigating excessive glycolysis, stabilizing pH, enhancing antioxidant capacity, and modulating the formation of flavor-deteriorating substances. Finally, we synthesize current challenges and future research avenues concerning the mechanisms by which this axis regulates metabolism and thereby influences meat quality and spoilage. Our goal is to provide theoretical foundations and practical strategies for producing high-quality and safe pork via nutritional interventions targeting the gut-muscle axis.