A comprehensive insight into effects of green tea extract in polycystic ovary syndrome: a systematic review

Vahid Maleki,Jalal Moludi,Mohammad Alizadeh,Fatemeh Pourteymour Fard Tabrizi,Parisa Varshosaz,Ehsaneh Taheri,Mahdi Shadnoush,Seyed Hossein Yahyazadeh Jabbari,Mehri Seifoleslami,Hamed Jafari-Vayghan

doi:10.1186/s12958-021-00831-z

Abstract

BackgroundPolycystic ovary syndrome (PCOS), as the most common endocrine disorder in reproductive-aged women, is characterized by oxidative stress and ovarian tissue inflammation. Green tea extract (GTE) potentially possesses therapeutic effects for PCOS because of the antioxidant and anti-inflammatory compounds. This systematic review evaluates the potential roles of GTE on metabolic variables, hormone levels, and ovarian function in PCOS.MethodsA systematic review was conducted of published studies reporting the effects of GTE on PCOS. Several major databases, including PubMed, SCOPUS, and Google Scholar, were searched up from inception to April 2021. Clinical trials and animal studies that assessed the effects of GTE on PCOS were eligible for inclusion.ResultsOf 314 articles found in the search, four human studies and four animal studies were included. All studies in humans showed the effects of GTE on weight loss. GTE’s effect on decreasing testosterone levels in humans and LH levels in animals were also reported. In addition, increases in FSH and progesterone levels in animal models were observed. Although GTE improved fasting blood sugar and insulin levels, the effect of GTE on inflammatory parameters, such as TNF-alpha and IL-6 and antioxidant status, was limited to animal studies.ConclusionTherefore, this review suggests that GTE could be considered a potential agent to attenuate PCOS complications mainly due to its effect on weight loss and glycemic levels. However, more studies are needed to formulate conclusions about the effects and mechanisms of GTE in PCOS.

Highlights

Polycystic ovary syndrome (PCOS), as the most common endocrine disorder in reproductive-aged women, is characterized by oxidative stress and ovarian tissue inflammation
Mombaini et al reported that body weight, Body mass index (BMI), waist circumstance (WC), and body fat percentage decreased statistically significantly after green tea extract (GTE) 500 mg/day for 45 days in women with PCOS (P < 0.05) [25]
42 Wistar female rats were divided into 7 equal groups: control, PCOS control, PCOS treated with aqueous extract of green tea (50 and 100 mg/kg, PCOS treated with catechin (50 and 100 mg/kg) and PCOS treated with clomiphene citrate (1.5 mg/kg, 24 days)

Summary

Introduction

Polycystic ovary syndrome (PCOS), as the most common endocrine disorder in reproductive-aged women, is characterized by oxidative stress and ovarian tissue inflammation. Green tea extract (GTE) potentially pos‐ sesses therapeutic effects for PCOS because of the antioxidant and anti-inflammatory compounds. Polycystic ovarian syndrome (PCOS) affects about 5-20% of women of reproductive ages [1] and is one of the most common and complicated hormonal disorders. This condition is accompanying by clinical symptoms, including irregular menstruation, increased androgens, Maleki et al Reprod Biol Endocrinol (2021) 19:147 resistance and hyperinsulinemia [7]. Studies have shown that green tea extract (GTE), as a strong antioxidant compound, has anti-obesity [15], anti-diabetes [16], anti-cardiovascular [17], anti-angiogenesis [18], anticancer [19] and neuroprotective properties [20]

Methods

Results

Discussion

Conclusion