Currently, 50% of women of reproductive age are obese, and one in seven live births is affected by hyperglycemia in mothers with gestational diabetes. To examine the impact of intrauterine overnutrition on the kidneys of the offspring, we generated a novel mouse model by feeding female C57BL6J mice with either control diet (CD) or high-fat diet (HFD, 60% Lipid) during gestation and feeding the male offspring with CD after weaning, allocated to two groups of male offspring, CD and HFD. CD and HFD had similar body weights, blood pressure and urinary albumin levels, but lower serum creatinine levels in HFD (CD; n=17, HFD; n=11, p<0.001), which might be due to renal hyperfiltration. Histologically, HFD presented renal tubular vacuolation at 4 weeks of age and glomerulosclerosis and intrarenal arteriosclerotic lesions at 15 weeks of age. Moreover, perirenal beige fat phenotype was lost in HFD at 4 week of age, presenting white adipose cells unlike the small adipose cells in CD, suggesting that maternal overnutrition induced systemic metabolic abnormality in offspring. Synchrotron phase-contrast micro-CT showed that HFD at 14.5 dpc showed asignificant increase in total kidney volume (CD; n=4, HFD; n=6, p<0.001). On the contrary, no significant difference in renal artery diameter was observed (p=0.52). Blood flow is determined by the supplying vascular diameter due to Murrays’ minimum energy hypothesis. Therefore, we studied the ratio of blood flow as the 3rd power of the diameter of fetal renal artery per renal volume, indicating no significant difference between CD and HFD (p=0.42). Despite of preserved blood supply, the protein expression of HIF-1α, the key hypoxic transcription factor, was higher in HFD than that in CD, suggesting increased oxygen demand due to maternal overnutrition-induced renal metabolism. Maternal overnutrition induces supply-demand mismatch leading to renal hypoxia in the fetus, which persists into adulthood in the offspring, which might promote susceptibility to diabetic nephropathy. Disclosure T.Takiyama: None. Y.Takiyama: None. R.Bessho: None. H.Kitsunai: None. Y.Takiyama: Research Support; Boehringer Ingelheim Japan, Inc., Taisho Pharmaceutical Holdings Co., Ltd., Ono Pharmaceutical Co., Ltd., Abbott Japan Co., Ltd., Roche Diabetes Care, MSD Life Science Foundation, Japan Society for the Promotion of Science, Teijin Pharma Limited, Kyowa Kirin Co., Ltd., Sumitomo Dainippon Pharma Co., Ltd., Eli Lilly Japan K.K.
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