Effects of Succinate on Growth Performance, Meat Quality and Lipid Synthesis in Bama Miniature Pigs

Simple Summary: Succinate is an important product of the fermentative metabolism of dietary fiber, and similar to propionate, high levels of succinate in the gut modulate the body's inflammatory response, glucose tolerance, and lipid metabolism. Our study showed that the addition of 1% succinate to pig diets promoted growth and fat deposition capacity without affecting feed intake, remodeled the fatty acid content of the longissimus dorsi muscle, and consequently improved meat quality. Further, we isolated and cultured primary porcine preadipocytes. The results showed that succinate increased the expression of genes related to adipogenic differentiation while decreasing the levels of genes related to lipolysis and promoting the formation of cellular lipid droplets. Mechanistically, dietary supplementation with succinate increases succinylation modification in adipose tissue to promote facilitated lipogenesis. This suggests that it is feasible and important to improve fatty acids and meat quality in porcine muscle through dietary succinate supplementation. Succinate, one of the intermediates of the tricarboxylic acid cycle, is now recognized to play a role in a broad range of physiological and pathophysiological settings, but its role in adipogenesis is unclear. Our study used Bama miniature pigs as a model to explore the effects of succinate on performance, meat quality, and fat formation. The results showed that adding 1% succinate significantly increased the average daily gain, feed/gain ratio, eye muscle area, and body fat content (p < 0.05), but had no effect on feed intake. Further meat quality analysis showed that succinate increased the marbling score and intramuscular fat content of longissimus dorsi muscle (LM), while decreasing the shear force and the cross-sectional area of LM (p < 0.05). Metabolomics analysis of LM revealed that succinate reshaped levels of fatty acids, triglycerides, glycerophospholipids, and sphingolipids in LM. Succinate promotes adipogenic differentiation in porcine primary preadipocytes. Finally, dietary succinate supplementation increased succinylation modification rather than acetylation modification in the adipose tissue pool. This study elucidated the effects of succinate on the growth and meat quality of pigs and its mechanism of action and provided a reference for the role of succinate in the nutrition and metabolism of pigs.