Objective To investigate the effect of metformin ( MET) on learning and memory behavior in HFD-induced insulin-resistant rats.Methods Thirty male Sprague-Dawley (SD) rats were divided into three groups to receive either a normal diet (Control group) or a high-fat diet (two HFD groups) for four weeks(HFD+MET).From two HFD groups, one received vehicle ( HFD group ) alone and other MET administration ( HFD+MET group ) .MET was dissolved in drinking water at a concentration of 2 mg/ml.All rats were subjected to the glucose tolerance test ( GTT) and behavioral tests using the elevated plus maze ( EPM ) , open field test ( OFT ) , Morris water maze ( MWM ) test and the step-through passive avoidance test ( PA) after four-week consecutive MET treatment .Blood samples were collected for determination of glucose. Results MET attenuated the glucose resistant condition and improved cognitive behavior in MWM and PA, vs the HFD group. Conclusion MET can improve the impaired learning and memory behavior in HFD-induced insulin-resistant rats.

Urine is not sterile but contains a complex urinary microbiome that is established as early as infancy and gradually refines with age. There are great differences in urinary microbiome of different ages and gender. At present，the core urinary microbiome of children has not reached a consensus. The urinary microbiome plays an important role in maintaining the integrity of urothelium，reducing the overgrowth of pathogenic bacteria，and local immune function. Changes in microbial diversity and composition are associated with various diseases of the urinary system，especially in urinary tract infections. In recent years，research on the relationship between urinary microbiome composition，microbiome，and urinary tract infection in children has been deepening. Therefore，this review aims to provide an overview of the urinary microbiome and its role in urinary tract infection in children，and to summarize the methods of intervening and reshaping the urinary microbiome in children to prevent recurrent urinary tract infections.