Comparison of IL-8, IL-6 and PGE₂ Formation by Visceral (Omental) Adipose Tissue of Obese Caucasian Compared to African-American Women

Background: One of the key consequences of obesity is an enhanced release of cytokines such as IL-8 and IL-6 by adipose tissue. There may be differences in adiposity, inflammatory markers, and medical co-morbidity between morbidly obese African-American (AA) and Caucasian (CA) women. We hypothesized that there are ethnic differences in inflammatory markers and medical co-morbidities. Methods: We compared the mRNA content in omental fat and the release of IL-8, IL-6 and PGE₂ after a 4-hour incubation of explants of adipose tissue in women undergoing bariatric surgery. In addition, medical co-morbidities and fat measurements were examined and compared. Results: Medication usage differed, with CA women being three times more likely to report taking medication for depression compared to AA women (P≤0.001). IL-8 and PGE₂ release over 4 hours by omental fat in vitro was the same in CA and AA women. Similar results were seen with respect to the COX-2 mRNA and IL-8 mRNA values at the start and at the end of the incubation. In CA and AA women, the IL-6 mRNA content in fat immediately after removal from the patients was the same. Conclusions: In morbidly obese women seeking bariatric surgery, there are little ethnic differences between cytokine release by omental adipose tissue explants in vitro, or the mRNA content in omental adipose tissue of IL-6, IL-8 or COX-2. The only noted difference between AA and CA morbidly obese women was the greater use of antidepressants by CA women.