Estrogenicity of Outer Scales of Onion on Reproductive functions of Mice

Objectives: This study aimed to investigate the estrogen-like activities of the outer scales of onion and garlic. Methods: This work compared the estrogenic effects induced by estradiol and the plant extract in vivo and in vitro models of immature mice. Uterine wet weight/body weight ratios were determined. Uterotrophic bioassay (increased epithelial cell height, and gland development), immunohistochemical assay for the estrogen receptor and proliferative marker Ki67 and uterine contractility were investigated. Results: Onion extract has the capacity to induce proliferative changes in the uterus that are analogous to those induced by estrogens, it also increased the wet uterine weight, and epithelial cell height. Also the frequency and amplitude of myometrial contractility were significantly increased in the group treated by onion extract. This estrogenic activity is attributed to quercetin and daidzein. Conclusion: Our results support the possible estrogenic properties of the onion extract compounds. INTRODUCTION The importance of estrogens in homeostatic regulation of many cellular and biochemical events is well illustrated by the pathophysiological changes that occur with estrogen deficiency. As a result, natural estrogenic alternatives for the treatment of menopausal pathologies and symptoms are frequently considered, because this offers the hope of improved safety and greater compliance. Onion and garlic worldwide-consumed vegetables are as a rich source of dietary quercetin known as strong anti-oxidant with ability to chelate metals and scavenge free radicals, which in turn inhibits lipid peroxidation. Many studies have presented other biological activities of quercetin that may be beneficial to health. It can inhibit platelet aggregation and/or broad spectrum of enzymes and has been demonstrated to have anti-inflammatory properties. Through these actions quercetin may contribute to protection from aging, vascular diseases and certain forms of cancer what suggests results of numerous epidemiological studies.1 Quercetin, a natural pentahydroxyflavone is believed to exhibit estrogenic and anticancer activity by acting as an effective radical-scavenger against oxidative cell damage. Various epidemiological studies have shown that quercetin and related isoflaEstrogenicity of Outer Scales of Onion on Reproductive functions of Mice Zienab A. ALREFAIE MD Hanan A. MOSTAFA PhD Sabah H. El-Gayed PhD Abdolmonem A. Al-Hayani PhD