Adiponectin and leptin: Potential tools in the differential diagnosis of pediatric diabetes?

Abstract

The incidence of type 1 and type 2 diabetes mellitus in the pediatric population has increased over the past decade. The practitioner is often faced with the challenge of differentiating between type 1 and type 2 diabetes at the time of initial diagnosis because of the overlap of clinical and laboratory characteristics between these two entities. Adipokines are proteins secreted by the adipose tissue. Leptin and adiponectin are two adipokines that have been extensively studied in vitro, in animal studies, and in human subjects with type 1 and type 2 diabetes. Leptin and adiponectin play a significant role in the regulation of lipid and carbohydrate metabolism. Adiponectin increases insulin sensitivity in both the liver and skeletal muscle. Leptin decreases appetite, increases energy expenditure, suppresses insulin synthesis and secretion and increases insulin sensitivity. Changes in the secretion or sensitivity to leptin and adiponectin may contribute to the development of type 1 and type 2 diabetes. Adiponectin is higher in adult and pediatric patients with type 1 diabetes compared to those with type 2 diabetes. Data regarding leptin levels are contradictory. Most studies report decreased serum leptin at the time of diagnosis in type 1 diabetes compared to type 2 diabetes subjects and non-diabetic controls. This paper will review basic research and clinical evidence supporting the role of adiponectin and leptin in the development of type 1 and type 2 diabetes and discuss their potential use as tools in the differential diagnosis of pediatric diabetes.

Serum Adipokine Levels in Type 1 Diabetic Patients: Association with Carotid Intima Media Thickness

“…Thus, increased resistin in type 1 DM patients seems to be suggestive of subclinical atherosclerosis. Because serum resistin levels are generally unrelated to markers of insulin resistance 15,16 and the association of adiponectin and leptin with insulin resistance seems to be more evident, 5,6,9,10 the sole relationship of resistin with CIMT in this population of type 1 DM patients raises a question about the association of insulin resistance with macrovascular complications.…”

Serum adipokines and vitamin D levels in patients with type 1 diabetes mellitus

“…In contrast to type 2 diabetes, involvement of adipose tissue in the low-grade systemic inflammation observed in T1DM has been investigated far less. Indeed, alterations in circulating levels of adipokines in T1DM indicate adipose tissue involvement in T1DM pathogenesis [8]. …”

Leptin-to-Adiponectin, Adiponectin-to-Leptin Ratios, and Insulin Are Specific and Sensitive Markers Associated with Polycystic Ovary Syndrome: A Case–Control Study from Bahrain

“…10 On the other hand, it has been suggested that adiponectin increases tissue fat oxidation, leading to reduced levels of fatty acids and tissue triglyceride content, thus increasing insulin sensitivity. 11 Therefore, leptin and adiponectin with respective proatherogenic and antiatherogenic properties, and changes in their secretion or sensitivity may contribute to the development of type 2 diabetes and coronary artery disease; they can be important mediators linking adiposity and atherosclerosis to PCOS. 12 Recent studies highlight the importance of leptin-toadiponectin (L/A) and adiponectin-to-leptin (A/L) ratios related to obesity, IR, coronary artery disease, and stroke in different populations in Europe and Asia.…”