The effect of cesarean delivery on the neonatal gut microbiome in an under-resourced population in the Bronx, NY, USA.

BACKGROUND: Neonatal and early-life gut microbiome changes are associated with altered cardiometabolic and immune development. In this study, we explored Cesarean delivery effects on the gut microbiome in our high-risk, under-resourced Bronx, NY population. RESULTS: Fecal samples from the Bronx MomBa Health Study (Bronx MomBa Health Study) were categorized by delivery mode (vaginal/Cesarean) and analyzed via 16 S rRNA gene sequencing at four timepoints over the first two years of life. Bacteroidota organisms, which have been linked to decreased risk for obesity and type 2 diabetes, were relatively reduced by Cesarean delivery, while Firmicutes organisms were increased. Organisms belonging to the Enterococcus genus, which have been tied to aberrant immune cell development, were relatively increased in the Cesarean delivery microbiomes. CONCLUSION: Due to their far-reaching impact on cardiometabolic and immune functions, Cesarean deliveries in high-risk patient populations should be carefully considered.

Downregulation of the kidney glucagon receptor, essential for renal function and systemic homeostasis, contributes to chronic kidney disease.

The glucagon receptor (GCGR) in the kidney is expressed in nephron tubules. In humans and animal models with chronic kidney disease, renal GCGR expression is reduced. However, the role of kidney GCGR in normal renal function and in disease development has not been addressed. Here, we examined its role by analyzing mice with constitutive or conditional kidney-specific loss of the Gcgr. Adult renal Gcgr knockout mice exhibit metabolic dysregulation and a functional impairment of the kidneys. These mice exhibit hyperaminoacidemia associated with reduced kidney glucose output, oxidative stress, enhanced inflammasome activity, and excess lipid accumulation in the kidney. Upon a lipid challenge, they display maladaptive responses with acute hypertriglyceridemia and chronic proinflammatory and profibrotic activation. In aged mice, kidney Gcgr ablation elicits widespread renal deposition of collagen and fibronectin, indicative of fibrosis. Taken together, our findings demonstrate an essential role of the renal GCGR in normal kidney metabolic and homeostatic functions. Importantly, mice deficient for kidney Gcgr recapitulate some of the key pathophysiological features of chronic kidney disease.