Effect of high‐fat diet (HFD) on blood pressure and placental levels of tumor necrosis factor (TNF)‐α and soluble fms‐like tyrosine kinase (sFlt)‐1 in pregnant rats

Abstract

During preeclampsia (PE), placental ischemia increases circulating levels of inflammatory and anti‐angiogenic factors that ultimately leads to hypertension and proteinuria. While obesity is a leading risk factor for developing PE, the mechanisms whereby obesity increases this risk are unclear. Our aims were to examine the effects of HFD on cardiovascular and metabolic systems of normal pregnant rats. Twelve‐week‐old Sprague‐Dawley female rats were fed a normal diet (ND, 13% fat kcal; n=12) or HFD (40% fat kcal). After 9 weeks, rats receiving HFD were grouped in obese prone (OP, weight gain=78.6±2.2 g; n=10) and obese resistant (OR, wg=57.4±2.0 g; n=11) (vs. ND wg=53.6±3.2 g; P<0.05). Rats were then allowed to breed, and mean arterial pressure (MAP) was measured by carotid catheters and tissues were harvested at gestational day 19. Body weight/litter size and visceral fat mass were similar in ND, OR and OP (32.0±2.6 vs. 32.7±2.6 vs. 30.0±1.4 g and 10.9±0.6 vs. 12.2±0.6 vs. 13.2±1.0 g; P>;0.05). MAP was also similar in ND, OR and OP (112±7 vs. 108±3 vs. 110±4 mmHg; P>;0.05). Placental levels of TNFα and sFlt1 were comparable between ND, OR and OP (1.0±0.1 vs. 1.5±0.2 vs. 1.2±0.1 ng/μg and 0.8±0.1 vs.0.9±0.1 vs. 0.9±0.1 pg/μg; P>;0.05). In summary, while HFD increases body weight in OP virgin rats, HFD in OP pregnant rats had no effect on blood pressure regulation or placental levels of TNFα and sFlt1. Funding: HL51971 and HL105324.