Subclinical Inflammation and Lymphocytes in Subcutaneous and Visceral Adipose Tissue—The Influence of Pregnancy and Gestational Diabetes Mellitus

Abstract

Obesity and type 2 diabetes mellitus are accompanied by low-grade inflammation and changed immune cell composition in adipose tissue. However, little is known about subclinical inflammation in gestational diabetes mellitus (GDM). The aim of our study was to analyse lymphocyte populations in subcutaneous (SAT) and visceral adipose tissue (VAT) together with systemic levels and mRNA expression of selected inflammatory markers in these depots and placenta. Thirty-seven pregnant females - 21 with GDM (GDM group) and 16 without GDM (P group) - were included into the study. Blood samples were taken in 28th-32th and 36th-38th gestational week and 6-12 months after delivery and SAT, VAT and placental samples were obtained during delivery. Lymphocytes were assessed as percent of CD45+ cells measured by flow cytometry. In both groups CD45+ lymphocytes were higher in VAT compared to SAT (19.2 ± 2.2 vs. 6.5 ± 0.7%, p<0.001 for GDM and 18.3 ± 3.4 vs.7.8 ±1.6, p=0.0for P, respectively). In GDM group T helper (CD4+) cells were higher in SAT compared to VAT (37.6 ± 2.4 vs. 28.6 ± 2.6%, p=0.019), resulting in a higher ratio of CD4+/CD8+ cells. Similarly, the amount of B (CD19+) and NKT (CD16/56+CD3+) cells was higher in SAT relative to VAT in GDM group, but not in P group. In contrast, NK (CD15/56+CD3-) cells were increased in VAT compared with SAT in GDM group (17.9 ± 3.1 vs. 9.1 ± 1.3%, p=0.015), while no difference was seen in P group. CRP levels did not differ between GDM and P group, while TNF-α concentrations were higher in GDM throughout the study (7.92 ± 0.69 vs. 4.59 ± 0.61 pg/ml, p=0.001). Placental mRNA expression of IL-10 and IL-8 was elevated in GDM vs. P group with no difference between SAT and VAT depots. Taken together GDM is associated with increased systemic TNF-α levels and changed lymphocyte content in different adipose tissue depots. These changes could be in part responsible for increased risk of complications for both mother and child during and after pregnancy. Disclosure A. Cinkajzlova: None. K. Anderlová: None. P. Simjak: None. Z. Lacinová: None. J. Klouckova: None. H. Kratochvilova: None. H. Krejci: None. M. Mraz: None. M. Haluzik: None. M. Krsek: None.