Objective: Metabolic syndrome (MS) is a cluster of metabolic abnormalities associated with obesity, insulin resistance (IR), dyslipidemia, and hypertension in which inflammation plays an important role. Few studies have addressed the role played by T cell-derived cytokines in MS. The aim of the study was to look at the T-helper (Th) 1 (interleukin [IL]-12, IL-2, and interferon-γ [IFN-γ]) and Th2 (IL-4, IL-5, and IL-13) cytokines in MS in the high-risk Asian Indian population.
Research design and methods: Study subjects were recruited from the Chennai Urban Rural Epidemiology Study. MS was defined using National Cholesterol Education Program-Adult Treatment Panel III criteria modified for waist according to World Health Organization Asia Pacific guidelines. Serum cytokine profile was determined by multiplex cytokine assay in subjects with (n = 21) and without (n = 33) MS.
Results: Both Th1 and Th2 cytokines showed up-regulation in MS. IL-12 (5.40 pg/mL in MS vs. 3.24 pg/mL in non-MS; P < 0.01), IFN-γ (6.8 pg/mL in MS vs. 4.7 pg/mL in non-MS; P < 0.05), IL-4 (0.61 pg/mL in MS vs. 0.34 pg/mL in non-MS; P < 0.001), IL-5 (4.39 pg/mL in MS vs. 2.36 pg/mL in non-MS; P < 0.001), and IL-13 (3.42 pg in MS vs. 2.72 pg/mL in non-MS; P < 0.01) were significantly increased in subjects with MS compared with those without. Both Th1 and Th2 cytokines showed a significant association with fasting plasma glucose level even after adjusting for age and gender. The Th1 and Th2 cytokines also showed a negative association with adiponectin and a positive association with the homeostasis model of assessment of IR and high-sensitivity C-reactive protein.
Conclusions: Apart from pro-inflammatory cytokines, Th cytokines might play an important role in inflammation, IR, and MS.