PYY and obesity due to melanocortin 4 receptor deficiency: -Acetate, propionate and butyrate administration in mice protect against diet-induced obesity and insulin resistance.-Propionate and butyrate but not acetate induce gut hormones and reduces food intake.-Butyrate had minor effect in stimulation of GLP-1 through FFAR3.-FFAR3 KO mice shows normal body weight and glucose homeostasis, indicating some additional mediators are involves in these mechanism.-FFAR3 KO mice shows impair GLP-1 synthesis with altered in mRNA expression of Glucagon, PYY and active GLP-1 peptide.