INS and obesity due to melanocortin 4 receptor deficiency: Gut commensal Bacteroides acidifaciens has been proved to prevent obesity and enhance insulin sensitivity,57 and the frequency of Bacteroides acidifaciens is negative correlation with inflammation stage.58 In line with the previous studies, irradiated male mice represented lower systemic inflammation stage with s_Bacteroides_acidifaciens as a dominant strain in intestine (Figure S10C, Supporting Information).