Increased T-helper interferon-γ-secreting cells in obese children

Abstract

Objective: Leptin, an adipocyte-secreted hormone, has emerged as a potential candidate for the link between obesity and the proinflammatory state. Specifically, leptin modulates T-helper (Th) cells toward a Th1 phenotype, with the secretion of proinflammatory cytokines. The aim of this study was to evaluate the Th1/Th2 balance in obese children and its relation with hormonal and metabolic features. Study design: In 50 obese children and 20 control children, we measured the CD4-positive Th cells that secrete interferon (IFN)-g or interleukin (IL)-2 (taken as an index of Th1 cells), and IL-4 (taken as an index of Th2 cells) as well as serum glucose, insulin, insulin resistance (IR) index (as homeostasis model assessment model (HOMA)), lipid profile, aminotransferases, leptin and ghrelin. Obese children also underwent dual energy X-ray absorptiometry scan measurements, and liver ultrasound scanning. Results: Geometric mean percentages of IL-2-and IL-4-CD4 secreting cells in obese children were not significantly different from those found in control children. However, the geometric mean percentage of CD4-positive T cells secreting IFN-g was significantly higher in the obese than in the control (P , 0.0001, t-test) group. Within the entire group of study children, the percentage of IFN-g-positive cells was positively associated with leptin (P ¼ 0.002), insulin (P , 0.00 005), and HOMA-IR values (P , 0.00 005). However, when these associations were restricted to the group of obese subjects, insulin and HOMA-IR values, but not leptin, retained statistical significance. Yet, in the obese group, the percentage of IFN-g-positive cells was associated with nonalcoholic steatohepatitis (NASH) (P ¼ 0.001), but not with body mass index-standard deviation score and total body fat mass. Conclusions: In obese children, a shift to Th1-cytokine profile dominated by the production of IFN-g is related to insulin resistance as well as to NASH independently of anthropometric features and other metabolic characteristics. The prevalent Th1 pattern of secreted cytokines may be regarded as a mechanism contributing to inflammation in obesity.European Journal of Endocrinology 154 691-697

Levels of Antibodies to Microorganisms Implicated in Atherosclerosis and of C-Reactive Protein among Atomic Bomb Survivors

“…In general, both CD4 T-and B-cell counts and percentages are higher in obese individuals than in lean individuals, and these increases are associated with risk factors of metabolic diseases, e.g., higher triglyceride and lower high-density lipoprotein (HDL) cholesterol levels. It has also been reported that peripheral T cells in obese individuals are somewhat activated, displaying increased expression levels of surface CD25 (a subunit of the IL2 receptor) and polarization towards a pro-inflammatory type-1 (T H 1) phenotype (10)(11)(12). It should be noted here that metabolic abnormalities, including serum levels of high triglyceride, low HDL cholesterol and fatty liver development, have been reported in association with radiation dose among A-bomb survivors (13)(14)(15).…”

Increased activity of interleukin-23/interleukin-17 proinflammatory axis in obese women

“…This seems to be in contrast with the findings showing that the systemic immune response in obese children is skewed to Th1 profile, as demonstrated by an increase in numbers of IFN-gsecreting helper T cells. 10 In addition to the possibility that the increase in Th1 response in obesity might be age-and/or gender-related, it should be noted that it can also occur through downregulation of Th1 counter-regulatory Th2 response characterized by IL-4 secretion, 12 which was not assessed in our study.…”

“…8 Moreover, some recent findings suggest that inflammation-related tissue damage in organ-specific autoimmunity could be associated with the IL-23/IL-17-dependent T-helper cell response (that is, Th17 response), rather than with the activity of IL-12/IFN-g cytokine axis as the main driving power behind the so-called Th1 response. 9 Although there are some data indicating that Th1 response might be reduced in malnourished and increased in obese children, [10][11][12] IL-23…”

Vitamin A supplementation reduces the Th17-Treg – Related cytokines in obese and non-obese women

“…(31) found no significant difference between baseline concentrations of IFN-γ in obese versus nonobese women; whereas, Pacifico and cols. (32) showed that obesity is associated with increased T-helper IFN-γ secreting cells in obese children. This inconsistency might be explained by age and sex related response of immune cells or it can also occur because of counterregulatory mechanisms of Th1 versus Th2 immune cell response as revealed by Sumarac-Dumanovic and cols.…”