Endocrine Abstracts

Introduction: The adipocyte expansion is a critical process with implications in the pathogenesis of metabolic syndrome and insulin resistance associated to obesity. Impaired adipogenesis leads to dysfunctional, hypertrophic adipocytes, chronic low grade inflammation and insulin resistance.

Methods: Our study included 18 obese patients (13 females and 5 males) mean age 38.76±8.89 years and mean body mass index 46.06±6.48 kg/m2, referred for Laparoscopic Sleeve Gastrectomy procedure. Patients were divided in metabolic healthy obese, MHO (6 patients)and metabolic unhealthy obese, MUHO (12 patients) according to IDF criteria. Antropometric measurements, biochemical and hormonal profile were evaluated. Subcutaneous adipocyte size was assessed using Adiposoft software on microscopic images of formalin fixed adipose tissue. The subcutaneous adipose derived stromal/stem cells (ASCs) were isolated and the mesenchymal origin was demonstrated by cytoskeleton vimentin fluorescent staining. To evaluate the adipogenic capacity of these precursor cells derived from obese patients, the ASCs were grown to confluence and differentiated in vitro for 21±3 days using an adipogenic protocol. We evaluated the lipid accumulation in mature adipocytes by specific lipid dye(Oil Red O). Spectrophotometric analysis of the lipid stain was used to quantify the lipid accumulation and fluorescent nuclear dye with DAPI was used for accurate cell count of mature adipocytes.

Results: Mean adipocyte area was significantly lower in MUHO as compared to MHO(P<0.05) The lipid accumulation in mature adipocytes obtained by isolation, proliferation and differentiation of subcutaneous ASCs was between 12.5% and 108.76%, being significantly higher in the MUHO group(P<0.05) as compared to MHO. For both groups, significant correlations was found between lipid accumulation and HOMA-IR (P=0.01), C peptide (P<0.05) and morning cortisol levels (P<0.05). No significant correlation was found between lipid accumulation and age or body mass index (BMI).

Conclusion: The evaluation of subcutaneous adipocyte size and adipogenic potential of ASCs derived from subcutaneous adipose tissue could be a good predictor of the metabolic risk for obese patients.