Intrapancreatic Adipocyte Deposition in a Mouse Model of the Metabolic Syndrome

Introduction

Obesity is a major risk factor for the development of insulin resistance and type 2 diabetes mellitus [1]. However, due to reactive hyperinsulinemia only a minority of obese and insulin-resistant individuals develop overt diabetes mellitus. The mechanisms causing hyperinsulinemia are not fully understood, but several studies have demonstrated that adipocytes are able to secret signaling molecules to act on β-cells [2]. In line with this, our previous findings have identified Wnt-signaling molecules derived from adipocytes to regulate β-cell proliferation and insulin secretion [3]. However, it is not yet clear whether local intrapancreatic adipocyte depots exist, possibly allowing for paracrine actions of adipocyte-derived hormones. Therefore, the aim of this study was to investigate the presence of local adipocyte deposition within the pancreas of wild-type (C57BL/6) and New Zealand Obese (NZO) mice, the latter representing a model for the metabolic syndrome [4].

In this study we found the deposition of ectopic adipocytes in the pancreas of obese, hyperinsulinemic NZO mice. Furthermore, we showed the proximity of adipocytes to pancreatic islets, potentially allowing for paracrine effects.

References

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