A longitudinal study on the effect of obesity upon circulating renin-angiotensin system in normal pregnancy.

BACKGROUND AND AIMS: Obesity is the most common health issue in women of reproductive age, which profoundly affects maternal-fetal health. Despite progress in understanding key inflammatory and metabolic changes, the pathogenesis of the cardiovascular phenotype of obese pregnant women remains to be fully understood. This study aimed at: (i) evaluating the changes of the renin-angiotensin system (RAS) throughout pregnancy in obese vs normal weight (control) women, and (ii) evaluating the presence of any associations between maternal hemodynamic status and RAS changes. METHODS AND RESULTS: Thirty-eight normal weight and nineteen obese pregnant women were included. Clinical assessment, blood samples and maternal hemodynamic evaluation were performed at 12, 20, 30, and 36 weeks, while ultrasound assessment was scheduled at 20, 30, and 36 weeks of gestation. Measurements of sFlt-1, PlGF, Angiotensinogen, Renin, AngII, Ang1-7, ACE and ACE2 were performed by ELISA. Our data show that normotensive obese women had lower placental blood supply, as assessed by UV-Q and UV-Q/EFW, as compared to controls, and significantly higher levels of AngII and AngII/Ang1-7 ratio, which were inversely related to placental blood supply. CONCLUSIONS: Our study shows for the first time that normotensive obese women exhibited a significant progressive increase of AngII and AngII/Ang1-7 throughout pregnancy, which were inversely related to placental blood supply as assessed by UV-Q and UV-Q/EFW. Our data shed light on the early changes in pregnant obese women and suggest that RAS dysregulation is a prerequisite rather than a consequence of hypertensive disorders of pregnancy and other maternal neonatal complications.

Sex Differences in Proatherogenic Cytokine Levels.

BACKGROUND: It has been shown that sex affects immunity, including cytokine production. Given that atherosclerosis is an inflammatory disease promoted by specific cytokines, such as interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α, we aimed at evaluating whether sex could affect the levels of these proatherogenic cytokines in a group of healthy adults. In this analysis, we also included other cytokines and peptides that have been implicated in atherosclerosis development and progression. METHODS: A total of 104 healthy adults were recruited; we measured circulating levels of IL-1ß, IL-6, TNF-α, angiotensins and angiotensin-converting enzyme-2 (ACE2), as well as osteoprotegerin and receptor activator of nuclear factor κB ligand (RANKL). RESULTS: IL-1ß, IL-6, and TNF-α were significantly higher in men as compared to women. They were all associated with testosterone and the testosterone/estradiol ratio. They remained significantly associated with sex (but not with hormones) after being tested for potential confounders. CONCLUSIONS: Sex seems to influence the levels of proatherogenic cytokines. This is consistent not only with sex differences in vulnerability to infections but also with the higher cardiovascular risk exhibited by the male gender as compared to the female gender. Nevertheless, this association is only partly explained by hormone levels.