Endocrine Abstracts

Obesity is characterized by hyperactivated endocannabinoid System (ECS) in brain and periphery and by increased levels of circulating endocannabinoids (cECs), anandamide (AEA) and 2-arachidonoylglycerol (2AG). It is still debated whether in absence of obesity cECs are only modulated by adiposity or if they are associated with cardiometabolic parameters.

We recruited 155 healthy normal weight (NW, BMI: 18.5–24.9 kg/m²) drug-free volunteers (18–90 years) that, after informed consent, gave fasted blood. Plasma cECs were measured by a validated liquid chromatography–mass spectrometry method.

In females, (n=94) AEA (P=0.014) and 2AG (P<0.001) increased with age; AEA correlated with BMI (P=0.022), waist circumference (WC, P=0.009), triglycerides (P<0.001) and insulin (P=0.029), while 2AG correlated with diastolic (P=0.010) and systolic (P=0.001) blood pressure (DBP and SBP respectively), glucose (P=0.004) and triglycerides (P<0.001). In males (n=61), 2AG correlated with BMI (P=0.038), glucose (P=0.014), triglycerides (P<0.001), insulin (P=0.028) and both 2AG (P=0.008) and AEA (P=0.031) negatively correlated with HDL. After stepwise-multiple regression, triglycerides independently correlated with AEA (P=0.003) and 2AG (P=0.001) in females and with 2AG in males (P<0.001). In females 2AG independently correlated also with SBP (P=0.016) and glucose (P=0.021), while in males AEA independently correlated with SBP (P=0.038) and negatively correlated with HDL (P=0.047). Subjects were subdivided in healthy and dysmetabolic (HNW/DNW) subgroups (51/43females, 25/36males) according to the absence or presence of at least one alteration, respectively, among WC (≧88/102 cm, females/males), BP (≧130/85 mmHg), triglycerides (≧150 mg/dl), HDL (<50/40 mg/dl females/males), glucose (≧110 mg/dl). Female DNW had higher BMI, WC, BP, triglycerides (all P<0.001) and lower HDL (P=0.014) than HNW, also displaying higher AEA (P=0.005) and 2AG (P=0.003). In males, DNW had higher BP (P<0.001) and triglycerides (P=0.023) than HNW, but similar cECs. Finally, in NW condition cECs are independently associated with cardiometabolic parameters but not with adiposity parameters, and, particularly in females, can be considered biomarkers of metabolic impairments.