Introduction:
Peripheral adiposity is associated with better metabolic health and higher plasma adiponectin (ADPN) levels. Since ADPN is secreted mainly by adipose tissue (AT), it is intriguing that higher visceral adipose tissue (VAT) is associated with lower ADPN levels and poor metabolic health.
Hypothesis:
We hypothesized that various AT depots differ in their ability to secrete ADPN.
Methods:
Paired AT samples (VAT and subcutaneous adipose tissue (SAT)) were collected from 19 subjects (10 women, 15 obese) undergoing elective abdominal surgery. The samples were cultured and the supernatant was collected after 24 hours. ADPN levels released into the supernatant from VAT and SAT were measured using multiplex methods. Subjects were defined as obese or non-obese (NO) based on BMI > or ≤ 30kg/m2 respectively. Obese subjects were further classified as metabolically unhealthy obese (MUO) or metabolically healthy obese (MHO) based on presence or absence of type 2 diabetes mellitus, hypertension, or cardiovascular disease at the time of surgery.
Results:
Mean ADPN secretion levels from SAT and VAT were similar in NO subjects (17.3 ± 3.4 vs. 9.8 ± 13.0 ng/mL/mg, p=0.5) whereas the mean ADPN secretion was lower from VAT among obese subjects (15.9 ± 0.8 vs. 4.5 ± 0.2 ng/mL/mg, p=0.0002). ADPN secretion decreased from VAT (r=-0.16) and increased from SAT (r=0.33) with increased BMI (Fig.1). When MHO and MUO were compared, ADPN secretion from VAT in MHO was reduced only slightly (16.1 ± 8.2 vs. 4.0 ± 2.0 ng/mL/mg, p=0.07) whereas ADPN secretion was significantly reduced in MUO (15.9 ± 5.3 vs. 4.7 ± 4.6 ng/mL/mg, p=0.003).
Conclusions:
Reduced ADPN secretion from VAT in subjects with increasing BMI may explain lower circulating ADPN levels in obese individuals. Higher ADPN production from SAT and the relatively preserved secretion of ADPN from VAT may explain metabolic health in some obese individuals. Futures studies will help identify factors that control ADPN secretion from AT.
Effects of Weight Loss in Metabolically Healthy Obese Subjects after Laparoscopic Adjustable Gastric Banding and Hypocaloric Diet
