Obesity may induce RAAS activation in children

Obesity appears to play a major role in the activation of the renin‒angiotensin‒aldosterone system (RAAS), with a noticeable rise of angiotensin-converting enzyme (ACE) and ACE activities during childhood, reveals a recent study. In addition, sex differences are present in the association of ACE and ACE2 activities with blood pressure (BP).

A research team conducted this cross-sectional study in 313 children aged 8‒9 years who were included in the birth cohort Generation XXI (Portugal). They performed anthropometric measurements and 24-h ambulatory BP monitoring, as well as quantified ACE and ACE2 activities using fluorometric methods.

Children with overweight/obesity have significantly increased ACE and ACE2 activities relative to their normal weight counterparts (median, ACE: 39.48 vs 42.90 vs 43.38 mU/ml; p_trend=0.009; ACE2: 10.41 vs 21.56 vs 29.00 pM/min per ml; p_trend<0.001 in normal weight, overweight, and obesity, respectively).

In girls, night-time systolic (p<0.001) and diastolic BP (p=0.002) increased across tertiles of ACE activity. ACE2 activity correlated with higher night-time systolic (p=0.037) and diastolic BP (p=0.048) in girls with overweight/obesity and night-time diastolic BP in the body mass index z-score girl adjusted model (p=0.018).

Notably, median ACE2 levels were significantly greater among nondipper girls (16.7 vs 11.6 pM/min per ml; p=0.009).

“Our work shows that obesity is associated with activation of the renin−angiotensin−aldosterone system, with significant increase of ACE and ACE2 activities already in childhood,” the researchers said. “Also, we report sex differences in the association of ACE and ACE2 activities with BP.”