Do SCFA have a role in appetite regulation?

Abstract

The recently discovered SCFA-activated G-coupled protein receptors FFA receptor 2 and FFA receptor 3 are co-localised in L-cells with the anorexigenic 'ileal brake' gut hormone peptide YY, and also in adipocytes, with activation stimulating leptin release. Thus, SCFA such as acetate and propionate show promise as a candidate to increase satiety-enhancing properties of food. We therefore postulate SCFA may have a role in appetite regulation and energy homeostasis. SCFA can be delivered either directly within food, or indirectly via the colon by the provision of fermentable non-digestible carbohydrates. A review of studies investigating the effects of oral SCFA ingestion on appetite suggests that while oral SCFA ingestion is associated with enhanced satiety, this may be explained by product palatability rather than a physiological effect of SCFA. Colon-derived SCFA generated during microfloral fermentation have also been suggested to explain satiety-enhancing properties of non-digestible carbohydrates. However, findings are mixed from investigations into the effects of the prebiotic inulintype fructans on appetite. Overall, data presented in this review do not support a role for SCFA in appetite regulation.Acetate: Propionate: Acetic acid: Propionic acid: SCFA: Inulin: Oligofructose: Satiety Human subjects are living in an increasingly 'obesogenic' environment with easily accessed, energy dense foods and sedentary lifestyles. These 'obesogenic' factors can override homeostatic systems resulting in a gradual increase in the population body weight (BW) (1) . The need for strategies to prevent the rise in obesity is therefore becoming increasingly urgent. One strategy is to identify and develop foods that enhance satiety, thereby reducing subsequent energy intake (EI) (2,3) .SCFA have been suggested to have satiety-enhancing properties, with some researchers suggesting SCFA may explain the inverse association between dietary fibre intake and BW found in some observational studies (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16) . This review considers the evidence for SCFA having a role in appetite regulation, starting first with the description of SCFA, followed by a discussion of the SCFA-activated receptors FFA receptor 2 (FFA2) and FFA receptor 3 (FFA3), which provide a rationale that SCFA may have a role in energy homeostasis. Finally, studies that have investigated the effects of orally and colonically delivered SCFA on appetite are reviewed. SCFASCFA are organic fatty acids generated in the colon when non-digestible carbohydrates (NDC) such as dietary fibre, resistant starch and inulin resist digestion and absorption in the small intestine, instead proceeding to the colon to undergo bacterial fermentation. The SCFA formed comprise between one and seven carbon units, with acetate (two carbon units) being the most predominant anion in the colon, followed by propionate (three carbon units) and then Abbreviations: AUC, area under curve; BW, body weight; DP, degree of polymerisation; EI, energy intake; GLP-1, glucago...

Effects of resistant starch on behaviour, satiety-related hormones and metabolites in growing pigs

“…RS escapes enzymatic digestion in the small intestine and is largely fermented in the caecum and colon into short-chain fatty acids (SCFA) (De Leeuw et al, 2005;Darzi et al, 2011). Behavioural studies on pigs suggest that RS prolongs the duration of satiety (Bolhuis et al, 2010;Souza da Silva et al, 2012 and.…”

Effects of a novel propionate-rich sourdough bread on appetite and food intake

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Effects of alginate and resistant starch on feeding patterns, behaviour and performance in ad libitum-fed growing pigs

“…Regmi et al (2011) reported that RS increases absorption of short-chain fatty acids (SCFA) in portal vein-catheterized pigs. Production of SCFA in the colon prolongs the energy supply to the body, which may bridge the energy gap during the interprandial period (Rérat, 1996;Darzi et al, 2011). Throughout the day, a Pigs were observed in their home pen during 1 day at the start of weeks 7 and 12 using 4 min-instantaneous scan sampling (six intervals of 1 h during daytime).…”