# Effects of combined oral contraceptives and metformin on paraoxonase 1 lactonase activity and status in patients with polycystic ovary syndrome and insulin resistance

## TL;DR

This study examines how combined oral contraceptives and metformin affect antioxidant activity and insulin resistance in women with PCOS.

## Contribution

The study reveals how COCs and metformin together influence PON1 lactonase activity and oxidative stress in PCOS patients.

## Key findings

- Treatment increased PON1 lactonase activity and improved antioxidant capacity in HDL.
- BMI, insulin resistance, and hyperandrogenism were significantly reduced after treatment.
- PON1 activity correlated with metabolic and oxidative stress markers.

## Abstract

To investigate the effects of combined oral contraceptives (COCs) and metformin treatment on the lactonase activity and status of paraoxonase 1 (PON1), and oxidative stress levels in patients with polycystic ovary syndrome (PCOS) and insulin resistance (IR).

A prospective, self-controlled study.

Sixty patients diagnosed with PCOS and IR underwent three months of comprehensive therapy, including lifestyle modification, oral metformin (1000–1500 mg/day), and a COC (3 mg drospirenone and 20 µg ethinyl estradiol). Clinical data and blood samples were collected at baseline and after three months of treatment. PON1 levels, lactonase activity, and normalized lactonase activity (NLA), along with PON1 Q192R and C-108T genetic polymorphisms, oxidative stress markers, hormonal profiles, and metabolic parameters, were analyzed.

After treatment, significant decreases were observed in body mass index (BMI), Global Acne Grading System scores, androstenedione, fasting insulin, the homeostasis model assessment of insulin resistance index, and total antioxidant capacity (P < 0.05). In contrast, serum PON1 lactonase activity, apolipoprotein (apo)A1, triglycerides, and 2-h glucose levels were significantly increased (P < 0.05). Spearman’s correlation analysis showed that lactonase activity and PON1 status were correlated with serum apoA1, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol, total oxidant status, and the oxidative stress index (P < 0.05). Moreover, the group with improved NLA showed higher PON1 lactonase activity and HDL-C levels, whereas the group without improved NLA showed higher PON1 levels after treatment.

Treatment with COCs and metformin enhanced the antioxidant capacity of circulating HDL and improved BMI, glycolipid metabolism, IR, and hyperandrogenism in patients with PCOS and IR.

https://www.chictr.org.cn/showproj.html?proj=152682, identifier ChiCTR2200057114.