Decreased blood oxytocin levels in obesity and in patients with newly diagnosed type 2 diabetes

BACKGROUND. Obesity and type 2 diabetes (T2D) are common metabolic disorders. Oxytocin, a hypothalamic neuropeptide, has recently been recognized as a potential regulator of energy balance, appetite, and insulin sensitivity.

OBJECTIVE. To investigate the relationship between circulating oxytocin levels and metabolic parameters in individuals with obesity and newly diagnosed T2D.

MATERIALS AND METHODS. A total of 96 participants were enrolled, including 48 with normal glucose tolerance (NGT) and 48 with newly diagnosed T2D, each subdivided into normal-weight and obese groups. Anthropometric indices, glucose and lipid parameters, insulin, HbA_1c, and high-sensitivity C-reactive protein were measured. Insulin resistance and β-cell function were assessed using the HOMA model.

RESULTS. Circulating oxytocin levels were significantly lower in patients with T2D compared to NGT (p < 0.01), and in obese compared to normal-weight participants (p < 0.01). Low oxytocin was negatively correlated with BMI, waist circumference, HbA1c, glucose, insulin, lipids, and hs-CRP, but positively with β-cell function. Multiple regression analysis identified 2-hour glucose, BMI, and total cholesterol as independent predictors of oxytocin levels.

CONCLUSION. Patients with obesity and newly diagnosed T2D exhibit markedly reduced circulating oxytocin levels, associated with adverse metabolic profiles. These findings highlight oxytocin as a potential biomarker of early metabolic dysregulation and suggest new therapeutic perspectives.

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