Subclinical Inflammation and Adipose Tissue Lymphocytes in Pregnant Females With Gestational Diabetes Mellitus

Abstract

Context: Gestational diabetes mellitus (GDM) is accompanied by subclinical inflammation; however, little is known about local inflammation in adipose tissue and placenta.

Objective: To analyze systemic and local subclinical inflammation and adipose tissue lymphocyte content and phenotype in pregnant women with and without GDM.

Design: Observational study.

Settings: Academic hospital.

Patients: Twenty-one pregnant women with GDM (GDM group), 16 pregnant women without GDM (non-GDM group) and 15 nonpregnant control women (N group).

Interventions: Serum samples taken at 28 to 32 (visit 1 [V1]) and 36 to 38 (V2) gestational weeks and 6 to 12 months after delivery (V3) in the GDM and non-GDM group and before elective gynecological surgery in the N group. Subcutaneous (SAT) and visceral adipose tissue (VAT) obtained during cesarean delivery or surgery.

Main outcome measures: Serum levels and adipose tissue expression of proinflammatory cytokines, adipose tissue lymphocyte content and phenotype (for a subset of GDM and non-GDM subjects).

Results: Accented proinflammatory state in GDM was documented by increased circulating tumor necrosis factor-α (TNF-α) levels. In both groups of pregnant females total lymphocytes were higher in VAT compared to SAT. In GDM subjects B cells and NKT cells were higher in SAT compared to VAT and T helper cells were increased relative to SAT of non-GDM group, while no intercompartmental adipose tissue differences were seen in non-GDM women.

Conclusions: Pregnant females had higher total lymphocyte count in VAT relative to SAT regardless of GDM. In addition to increased systemic subclinical inflammation, GDM was associated with significant differences in lymphocyte composition between subcutaneous and visceral adipose tissue depots.

Keywords: adipose tissue; gestational diabetes mellitus; lymphocytes; subclinical inflammation.