Investigating Susceptibility to Diabetes Using Features of the Adipose Tissue in Response to In Utero Polycyclic Aromatic Hydrocarbons Exposure

Diabetes Metab J. 2016 Dec;40(6):494-508. doi: 10.4093/dmj.2016.40.6.494. Epub 2016 Aug 12.

Abstract

Background: In recent times, there has been an increase in the incidence of type 2 diabetes mellitus (T2DM) particularly in children. Adipocyte dysfunction provide a critical link between obesity and insulin resistance resulting in diabetes outcome. Further, environmental chemical exposure during early years of life might be a significant contributing factor to the increase in the incidence of T2DM. This study tests the idea that exposure to environmental contaminants (2-aminoanthracene [2AA]) in utero will show effects in the adipose tissue (AT) that signify T2DM vulnerability. 2AA is a polycyclic aromatic hydrocarbon found in a variety of products.

Methods: To accomplish the study objective, pregnant dams were fed various amounts of 2AA adulterated diets from gestation through postnatal period. The neonates and older offspring were analyzed for diabetic-like genes in the ATs and analysis of serum glucose. Furthermore, weight monitoring, histopathology and immunohistochemical (IHC) staining for CD68 in AT, adipocyte size determination and adiponectin amounts in serum were undertaken.

Results: Up-regulation of adiponectin and interleukin-6 genes were noted in the pups and older rats. Combination of intrauterine 2AA toxicity with moderate high fat diet exhibited gene expression patterns similar to those of the neonates. Elevated serum glucose levels were noted in treated groups. IHC of the AT indicated no significant malformations; however, CD68+ cells were greater in the animals treated to 2AA. Similarly, mean sizes of the adipocytes were larger in treated and combined 2AA and moderate high fat animals. Adiponectin was reduced in 2AA groups.

Conclusion: From the preceding, it appears intrauterine 2AA disturbance, when combined with excess fat accumulation will lead to greater risk for the diabetic condition.

Keywords: 2-Anthramine; Adipocytes; Adiponectin; Diabetes; Gene expression; Interleukin-6; Serum glucose.