MUC5AC and immune system disorder: Other authors have related the increased abundance of Bacteroides to its ability to produce SCFAs other than butyric acid, including succinate, propionate, and acetate, indicating that it might be implicated in the impairment of intestinal barrier function because these metabolites do not induce mucin production (224), resulting in the release of a large number of pro-inflammatory factors outside the intestine and causing immune dysfunction (224).