IntroductionSubcutaneous adipose tissue is an interesting source of autologous stem cells with a fundamental role in the pathophysiology of obesity, metabolic syndromes and insulin resistance. We hypothesize that obesity could alter the stromal-vascular fraction (SVF) and adipose stem cell (ASCs) functions, which could compromise its regenerative behavior. Furthermore, we aimed to evaluate whether ASCs derived from post bariatric surgery ex-obese women maintain their functions in a similar fashion as do those from individuals who have never been obese.MethodsThe SVF of subcutaneous adipose tissue from control (n = 6, body mass index – BMI - 27.5 ± 0.5 kg/m2), obese (n = 12, BMI 46.2 ± 5.1 kg/m2) and post bariatric surgery ex-obese (n = 7, initial BMI 47.8 ± 1.3 kg/m2; final BMI 28.1 ± 1.1 kg/m2) women were isolated and evaluated by flow cytometry. ASCs were tested for lipid accumulation by perilipin, adipose differentiation-related protein (ADRP) and Oil Red O staining after adipogenic stimulus. The cytokines secreted by the ASCs and after lipid accumulation induction were also evaluated.ResultsThe subcutaneous adipose tissue of obese and post bariatric surgery ex-obese women was enriched in pericytes (p = 0.0345). The number of supra-adventitial cells was not altered in the obese patients, but it was highly enriched in the post bariatric surgery ex-obese women (p = 0.0099). The ASCs of the post bariatric surgery ex-obese patients secreted more MCP-1 (monocyte chemoattractant protein-1; p = 0.0078). After lipid accumulation induction, the ASCs of the patients in all groups secreted less IL-6 than the ASCs with no adipogenic stimulus (p < 0.0001). Obese ASCs with lipid accumulation secreted the highest amount of IL-6 (p < 0.001) whereas the ASCs from the controls secreted the highest amount of adiponectin (p < 0.0001). The ASCs from the post bariatric surgery ex-obese patients showed the highest levels of lipid accumulation whereas those from the obese women had the lowest levels (p < 0.0001).ConclusionsSVF content and ASC behavior are altered in the subcutaneous adipose tissue of morbid obese women; these changes are not completely restored after bariatric surgery-induced weight loss. The cellular alterations described in this study could affect the regenerative effects of adipose stem cells. Further investigations are required to avoid jeopardizing the development of autologous stem cell-based therapies.

Objectives: To evaluate the prevalence of goiter and nodular disease in patients with class III obesity, and to correlate results with serum leptin levels and insulin resistance (IR) parameters. Subjects and methods: A cross-sectional study was performed to assess thyroid ultrasound (US) patterns, HOMA-IR, serum leptin, and TSH levels in obese patients and controls. Results: Thyroid volume was positively correlated with body mass index (BMI) (r = 0.240, p = 0.039) and with HOMA-IR (r = 0.329; p < 0.01). Thyroid US patterns were similar between groups. However, when data from the male group was considered, greater thyroid volume was detected in the obese group compared with controls (10.8 vs. 8.5 cm 3 ; p = 0.04). Also, nodules were more frequently detected (67% vs. 18%), as were nodules requiring FNAB (33.3% vs. 0%, p ≥ 0.05-0.09), in this group. Conclusion: Although IR did not correlate directly with the presence of nodules, the results support the hypothesis of a direct association between insulin resistance and thyroid volume. Arq Bras Endocrinol Metab. 2013;57(2):120-5 Keywords Obesity; insulin resistance; goiter; thyroid nodule RESUMO Objetivos: Avaliar a prevalência de bócio e doença nodular tireoidiana em pacientes com obesidade grau III e correlacionar os resultados com os níveis de leptina e parâmetros de resistência à ação da insulina (RI). Sujeitos e métodos: Estudo seccional foi desenvolvido realizando ultrassonografia (US) tireoidiana e níveis séricos de HOMA-IR e TSH nos pacien tes obesos e nos controles. Resultados: Volume tireoidiano foi positivamente correlacionado com índice de massa corporal (IMC) (r = 0,240, p = 0,039) e com HOMA (r = 0,329; p < 0,01). Volume tireoidiano e prevalência de doença nodular tireoidiana foram similares entre os grupos. Quando avaliado o subgrupo masculino, maiores volumes tireoidianos foram detectados no grupo dos obesos comparados aos controles (10,8 vs. 8,5 cm 3 ; p = 0,04), nódulos foram mais frequentes (67% vs. 18%), assim como nódulos com indicação de punção (33,3% vs. 0%, p ≥ 0,05-0,09). Conclusão: Embora RI não se correlacione diretamente com a presença de nódulos, os resultados suportam a hipótese da direta associação entre resistência à ação da insulina e volume tireoidiano. Arq Bras Endocrinol Metab.2013;57(2):120-5 Descritores Obesidade; resistência à insulina; bócio; nódulo da glândula tireoide

Summary Bariatric surgery has been recognized as the gold standard treatment for severe obesity. Although postbariatric surgery patients usually achieve and maintain substantial weight loss, a group of individuals may exhibit weight regain. Several factors are proposed to weight regain, including psychiatric comorbidity. The objective of the study is to conduct a systematic review and meta‐analysis of studies investigating the relationship between psychiatric comorbidity and weight regain. A systematic review through PubMed, Web of Science, Cochrane Library, Scopus, and PsycINFO was performed, following Preferred Reporting Items for Systematic Reviews and Meta‐Analyses (PRISMA). After a stepwise selection, 13 articles were included in the qualitative analysis and 5 were included for a meta‐analysis. Women was majority in most of the studies (87.6%), and a bypass procedure was the bariatric intervention most evaluated (66.8%), followed by gastric banding (32.1%) and sleeve (1.1%). Higher rates of postbariatric surgery eating psychopathology were reported in patients with weight regain. However, the association between general psychopathology and weight regain was not consistent across the studies. In the meta‐analysis, the odds of eating psychopathology in the weight regain group was higher compared with the nonweight regain group (OR = 2.2, 95% CI 1.54‐3.15). Postbariatric surgery eating psychopathology seems to play an important role in weight regain.

Background/ObjectivesThe pathological condition of obesity is accompanied by a dysfunctional adipose tissue. We postulate that subcutaneous, preperitoneal and visceral obese abdominal white adipose tissue depots could have stromal vascular fractions (SVF) with distinct composition and adipose stem cells (ASC) that would differentially account for the pathogenesis of obesity.MethodsIn order to evaluate the distribution of SVF subpopulations, samples of subcutaneous, preperitoneal and visceral adipose tissues from morbidly obese women (n = 12, BMI: 46.2±5.1 kg/m2) were collected during bariatric surgery, enzymatically digested and analyzed by flow cytometry (n = 12). ASC from all depots were evaluated for morphology, surface expression, ability to accumulate lipid after induction and cytokine secretion (n = 3).ResultsA high content of preadipocytes was found in the SVF of subcutaneous depot (p = 0.0178). ASC from the three depots had similar fibroblastoid morphology with a homogeneous expression of CD34, CD146, CD105, CD73 and CD90. ASC from the visceral depot secreted the highest levels of IL-6, MCP-1 and G-CSF (p = 0.0278). Interestingly, preperitoneal ASC under lipid accumulation stimulus showed the lowest levels of all the secreted cytokines, except for adiponectin that was enhanced (p = 0.0278).ConclusionsASC from preperitoneal adipose tissue revealed the less pro-inflammatory properties, although it is an internal adipose depot. Conversely, ASC from visceral adipose tissue are the most pro-inflammatory. Therefore, ASC from subcutaneous, visceral and preperitoneal adipose depots could differentially contribute to the chronic inflammatory scenario of obesity.