INS and metabolic syndrome: On the contrary, administration of amoxicillin in HFD-fed mice caused a significant decrease in Lactobacillus, Turicibacter, Desulfovibrio, Oscillospira, Streptococcus, Granulicatella., and a slight decrease in Rothia. Therefore, our data suggest that amoxicillin treatment could positively improve the metabolic syndrome pathology by improving the insulin signalling and maintaining intestinal barrier integrity by decreasing the abundance of microbiota linked to obese related metabolic disorders and gut inflammatory diseases.