Evaluation of Serum Preptin Levels in Patients With Polycystic Ovary Syndrome

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorders affecting women of reproductive age and is characterized by reproductive, endocrine, and metabolic abnormalities. Although the etiology of PCOS is multifactorial, insulin resistance and compensatory hyperinsulinemia are recognized as key mechanisms contributing to both the reproductive and metabolic manifestations of the syndrome. These metabolic disturbances increase the long-term risk of impaired glucose tolerance, type 2 diabetes mellitus, dyslipidemia, metabolic syndrome, and cardiovascular disease.

Preptin is a 34-amino acid peptide derived from the E-peptide region of pro-insulin-like growth factor II (pro-IGF-II) and is co-secreted with insulin by pancreatic β-cells. Experimental and clinical studies suggest that preptin enhances glucose-mediated insulin secretion and may participate in the regulation of glucose homeostasis. Elevated circulating preptin concentrations have been reported in several metabolic disorders associated with insulin resistance, including obesity and type 2 diabetes mellitus. However, its role in the pathophysiology of PCOS remains poorly understood, and the available evidence is limited and inconsistent.

The present study has been designed to investigate whether serum preptin concentrations differ between women with PCOS and women without PCOS and to explore the potential association between preptin and insulin resistance. By evaluating this novel metabolic peptide, the study seeks to improve understanding of the metabolic mechanisms underlying PCOS and to determine whether preptin may have potential utility as a biomarker associated with the syndrome.

Despite increasing interest in novel metabolic biomarkers, the clinical significance of preptin in PCOS remains unclear because only a limited number of studies have evaluated this peptide in women with PCOS. Furthermore, published findings are inconsistent regarding the relationship between circulating preptin concentrations and insulin resistance. The present study aims to provide additional evidence regarding serum preptin concentrations in women with PCOS and to explore their association with metabolic parameters. A better understanding of preptin biology may contribute to the identification of novel biomarkers involved in the metabolic pathophysiology of PCOS and may support future diagnostic and therapeutic research.

Inclusion criteria

• Female participants aged 18-45 years
• Diagnosis of PCOS according to Rotterdam criteria
• BMI <30 kg/m²
• No PCOS treatment during the previous 6 months
• Not pregnant or breastfeeding
• No active infection
• No rheumatologic or inflammatory disease
• No chronic systemic disease
• Written informed consent

Exclusion criteria

• Age <18 years or >45 years
• Pregnancy or breastfeeding
• PCOS treatment within the previous 6 months
• Active infection
• Rheumatologic or inflammatory disease
• Hypertension
• Diabetes mellitus
• Chronic kidney disease
• Refusal to participate