Biological Function of Short-Chain Fatty Acids and Its Regulation on Intestinal Health of Poultry

Abstract

Short-chain fatty acids (SCFAs) are metabolites generated by bacterial fermentation of dietary fiber (DF) in the hindgut. SCFAs are mainly composed of acetate, propionate and butyrate. Many studies have shown that SCFAs play a significant role in the regulation of intestinal health in poultry. SCFAs are primarily absorbed from the intestine and used by enterocytes as a key substrate for energy production. SCFAs can also inhibit the invasion and colonization of pathogens by lowering the intestinal pH. Additionally, butyrate inhibits the expression of nitric oxide synthase (NOS), which encodes inducible nitric oxide synthase (iNOS) in intestinal cells via the PPAR-γ pathway. This pathway causes significant reduction of iNOS and nitrate, and inhibits the proliferation of Enterobacteriaceae to maintain overall intestinal homeostasis. SCFAs can enhance the immune response by stimulating cytokine production (e.g. TNF-α, IL-2, IL-6, and IL-10) in the immune cells of the host. Similarly, it has been established that SCFAs promote the differentiation of T cells into T regulatory cells (Tregs) and expansion by binding to receptors, such as Toll-like receptors (TLR) and G protein-coupled receptors (GPRs), on immune cells. SCFAs have been shown to repair intestinal mucosa and alleviate intestinal inflammation by activating GPRs, inhibiting histone deacetylases (HDACs), and downregulating the expression of pro-inflammatory factor genes. Butyrate improves tight-junction-dependent intestinal barrier function by promoting tight junction (TJ) assembly. In recent years, the demand for banning antibiotics has increased in poultry production. Therefore, it is extremely important to maintain the intestinal health and sustainable production of poultry. Taking nutrition strategies is important to regulate SCFA production by supplementing dietary fiber and prebiotics, SCFA-producing bacteria (SPB), and additives in poultry diet. However, excessive SCFAs will lead to the enteritis in poultry production. There may be an optimal level and proportion of SCFAs in poultry intestine, which benefits to gut health of poultry. This review summarizes the biological functions of SCFAs and their role in gut health, as well as nutritional strategies to regulate SCFA production in the poultry gut.

Alterations in bacterial metabolites, cytokines, and mucosal integrity in the caecum of broilers caused by feed additives and host-related factors

“…This was in line with in several studies indicating the effects of SCFA on intestinal immunity as reviewed by Gasaly et al (2021) . It was proposed that SCFA may regulate cytokine production of the immune or epithelial cells by directly binding to certain receptors such as free fatty acid receptor (or G protein-coupled receptors) and/or by regulating target cell epigenetics after they were taken up into the cells ( Liu et al, 2021 ). Among SCFA, propionate demonstrated a relatively strong positive correlation with most of cytokines analyzed in this study, especially IL-4, IFN-γ and TGF-β2.…”

Structural characteristics of locust bean gum hydrolysate and its alleviating effect on dextran sulfate sodium-induced colitis

“…It has also been reported that SCFAs are closely associated with inflammation. They protect the integrity of the intestinal epithelium and promote the intestinal immune response, thereby protecting the intestinal wall and reducing the incidence of intestinal inflammation ( Liu et al, 2021 ). It has been demonstrated that SCFAs can effectively inhibit the inflammatory response of Caco-2 cells and maintain the tight junctions of intestinal mucosal epithelial cells ( Xi et al, 2022 ).…”

“…The sections were observed under an upright microscope (Eclipse E200, Nikon, Japan) and photographed using ImageView (Pooher, Shanghai, China). The histologic scores were evaluated as described previously (Guo et al, 2021), a score of 0-4 was given depending on the number of lesions in the colon and their severity.…”

COMPOSITION AND METABOLIC POTENTIAL OF THE INTESTINAL MICROBIOME OF Gallus gallus L. BROILERS UNDER EXPERIMENTAL T-2 TOXICOSIS AS INFLUENCED BY FEED ADDITIVES

“…Важная функция Firmicutes -это способность разлагать сложные полисахариды с последующим образованием короткоцепочечных жирных кислот (30). Короткоцепочечные жирные кислоты играют важную роль в энергетическом метаболизме хозяина, способствуя росту и нормальному функционированию клеток кишечника (31).…”

“…По мнению L. Liu с соавт. (31), протеолитические системы и селективный протеолиз рассматриваются в качестве ключевых регуляторов процессов опухолевой прогрессии; процессы протеолиза имеют непосредственное отношение к реакциям воспаления и деструкции тканей.…”