Relative Hypoleptinemia in Poorly Controlled Patients with Type 1 Diabetes

Introduction

Insulin sensitivity is strictly related to body fat mass. Several studies in type 2 diabetes (T2DM) demonstrated that insulin regulates leptin (Lep) per se, regardless of adiposity [1] [2]. On the contrary, plasma adiponectin (Apn), another molecule specifically secreted from adipocytes, is negatively correlated with insulin resistance and body mass index (BMI) [3] [4]. Unlike the HOMA-IR, an index of insulin resistance, the adiponectin/leptin ratio (A/L ratio) is not influenced by fasting glucose plasma levels and could be considered a sensitive and reliable marker of insulin resistance in T2DM. Type 1 diabetes mellitus (T1DM) is an organ-specific autoimmune disease resulting from the T-cell mediated destruction of pancreatic β-cells, though glycemic control is also related to reduction in insulin sensitivity. Although it is well known that adipocytokines, principally Lep, may influence T-cell function [5] [6], their role in insulin sensitivity has not been sufficiently investigated in Type 1 diabetes.

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Correspondence