Evaluation of the Protective Effect of Quercetin on Normal Ovary Cells Viability Induce by Clomiphene Citrate and Correlation with p53 Gene Expression

Infertility is one of the medical problems in the world today. Clomiphene citrate drug is used to treat infertility. One of the side effects of this drug is the formation of tumor tissue in the ovary. Quercetin is a flavonoid found abundantly in nature. Quercetin is found in many fruits, vegetables, leaves, seeds, and grains. Quercetin has the potential to be used in the treatment of cancer. The most well-known and common tumor suppressor gene in humans is the p53 gene. The p53 gene was discovered in 1979 and recognized as a tumor suppressor gene in 1989. This gene was recognized as the guardian of the genome in 1992 due to its role in maintaining the stability of the genome. The p53 gene is the most commonly mutated in human cancers. The purpose of this study is to evaluate the protective effect of quercetin on normal ovary cell viability induced by clomiphene citrate drug and its correlation with p53 gene expression.

In this research, Normal ovarian cells of the CHO cell line were used. Concentrations of 10, 50, 100, 500, and 1000 mg/ml quercetin 50 μM clomiphene citrate drug and 0.29 μg/ml cisplatin were prepared and added to the cultured cells for 24 hours. In this study, Clomiphene Citrate and Cisplatin are both positive controls. Cell viability was evaluated by MTT assay. RNA was extracted and p53 gene expression was analyzed by Real-Time PCR. In this study, the primer used for the p53 gene was designed using NCBI and primer3 sites. In this study, the internal control gene is GAPDH.

Results showed that the concentrations of 50, 100, 500, and 1000 mg/ml of quercetin reduced the toxicity of clomiphene citrate drug and cisplatin (both positive controls). So the higher quercetin concentration leads to a higher number of living cells and at 1000 mg/ml quercetin the number of living cells reached 83%. The results of Real-time PCR showed that Quercetin significantly increased the expression of the p53 gene compared to the positive control group (clomiphene citrate) and negative control (P<0.05). In the concentrations of 500 (P=0.0020) and 1000 (P<0.0001) quercetin compared to clomiphene citrate, this expression increase was more significant. Also, in the concentrations of 500 (P<0.0001) and 1000 (P<0.0001) quercetin compared to the negative control, a substantial increase in p53 gene expression was observed.

The findings of this study showed that the use of quercetin inhibits the cytotoxicity of clomiphene citrate and increases the expression of the p53 gene, and its effectiveness is dose-dependent. However, Our study may partially explain the role of quercetin in the tumorigenesis process in the development of cancer in normal ovarian cells.