Current Issue

Volume 11, Number 2, Jul-Sep 2017 Pages: 105-111

Evaluation of Relationship between Body Mass Index with Vitamin D Receptor Gene Expression and Vitamin D Levels of Follicular Fluid in Overweight Patients with Polycystic Ovary Syndrome


Esmat Aghadavod, Ph.D, 1, Hakimeh Mollaei, M.Sc, 2, 3, Mohammad Nouri, Ph.D, 4, Hamed Hamishehkar, Ph.D, 5, *,
Gametogenesis Research Center, Kashan University of Medical Sciences, Kashan, Iran
Research Center for Pharmaceutical Nanotechnology, Tabriz University of Medical Sciences, Tabriz, Iran
Department of Biology, Science and Research Branch of Islamic Azad University, Tehran, Iran
Women Reproductive Health Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
*Corresponding Address: P.O.Box: 51656-65811 Drug Applied Research Center Tabriz University of Medical Sciences Tabriz Iran Email:Hamishehkarh@tbzmed.ac.ir

Abstract

Background

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder associated with reproductive disorders and metabolic dysfunctions including insulin resistance. The roles of vitamin D in the regulation of metabolic modulations specifically involving insulin and reproduction processing are introduced. In addition, obesity appears to be closely associated with severity of PCOS. The present study is to evaluate the effect of body mass index (BMI) on vitamin D levels in follicular fluid and vitamin D receptor (VDR) expression levels in granulos cells.

Materials and Methods

A comparative study was conducted on 80 women with average age of 20-35 years referred for in vitro fertilization (IVF). Patients were divided into four groups, and serum levels of testosterone and insulin resistance (IR) were evaluated at the puncture time. Also, vitamin D levels of follicular fluid were evaluated. VDR gene expression was assayed by quantified-polymerase chain reaction (PCR) technique. Correlations were evaluated with calculation of the Spearman coefficient, and also independent relationships were assessed by means of multiple regression analysis.

Results

Vitamin D levels of follicular fluid decreased in PCOS patients compared with non-PCOS. Also, over-weight individuals had lower vitamin D levels compared with normal-weight patients. Vitamin D levels of follicular fluid were highly correlated with BMI (r=-0.51, P<0.01). Homeostatic model assessment-IR (HOMA-IR) values were significantly higher in women of PCOS/overweight and PCOS/normal weight in comparison with women of non-PCOS/normal weight (P<0.01). The gene expression data of VDR in granulosa cells were significantly lower in the PCOS/overweight group compared with the non-PCOS/normal weight (P<0.01).

Conclusion

The findings indicated significant differences in VDR gene expression in granulosa cells and vitamin D of follicular fluid in PCOS/overweight patients.