Acetyl-L-Carnitine Ameliorates Metabolic and Endocrine Alterations in Women with PCOS: A Double-Blind Randomized Clinical Trial

Introduction: Polycystic ovary syndrome (PCOS) is a common endocrine-metabolic disorder and the main cause of infertility in women of reproductive age. Affected women suffer from insulin resistance and present with an intense stress response. Treatment with insulin sensitizers alone and in combination is used to ameliorate the signs and symptoms associated with the disease. This study was designed to compare the endocrine and metabolic parameters as well as subjective and objective measures of stress in women with PCOS before and after treatment with acetyl-L-carnitine (ALC) and metformin plus pioglitazone.

Methods: A total of 147 women with PCOS were randomly assigned into two groups: the combo group (n = 72) received a combination of metformin, pioglitazone, and ALC (500 mg, 15 mg, and 1500 mg, respectively), twice daily; the Met + Pio group (n = 75) received metformin plus pioglitazone (500 mg, 15 mg, respectively) and placebo (citric acid plus calcium carbonate), twice daily for 12 weeks. Medications were discontinued when pregnancy was confirmed. The Perceived Stress Scale (PSS14) and Profile of Mood States (POMS) were employed as subjective measures of stress. The endocrine and metabolic functions of women with PCOS were assessed by measuring insulin, leutinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone, and adiponectin levels in fasting blood samples. Insulin resistance was calculated by Homeostatic Model Assessment of Insulin Resistance (HOMA-IR).

Results: Women at baseline had significantly elevated circulating concentration of insulin and low level of adiponectin. Treatment decreased insulin in both groups; however, the combo group showed a significant decrease (p = 0.001). Serum adiponectin level was raised significantly after treatment in both groups (p < 0.001). HOMA-IR also decreased in both groups (both p < 0.001). Testosterone, FSH, and LH significantly improved in both groups. LH also decreased in both groups; however, the change was significant only in the combo (metformin plus pioglitazone plus ALC) group (p = 0.013). Interestingly, there was a significant improvement in body circumference (p < 0.001) in the combo group. The PSS scores of the patients improved significantly (p < 0.001) in the combo group. Interestingly, regular menstrual cycles were found (97.2%) in the carnitine group, but in only 12.9% of the other group.

Conclusion: We conclude that addition of ALC therapy is superior to metformin plus pioglitazone in ameliorating insulin resistance, polycystic ovaries, menstrual irregularities, and hypoadiponectinemia in women with PCOS.

Trial registration: Trial registration: clinicalTrial.gov NCT04113889. Registered 3 October, 2019. https://clinicaltrials.gov/ct2/show/NCT04113889 .