Green and white teas consumption in the cell proliferation of endometrium of rats

The catechins presents in the green and white teas (originated from Camellia sinensis plant) are associated at reducing of cell proliferation in different kinds of cancers, with prevention of cardiovascular diseases and osteoporosis and they possess antioxidative and antibacterial activity. Despite the benefits of consumption of these teas, their catechins inhibit cell proliferation and steroidogenesis in swine granulosa cells in vitro cultivated. So it is also important to get an insight on the possible reproductive-related consequences of the use of green and white teas. Thus, the aim of this work was to verify the green and white teas influence in the cell proliferation in the endometrium of rats. For this purpose, 90 rats were divided into three groups, control group (CT, which is drinking only water ad libitum); GT group (which is drinking only commercial green tea, Amor a Vida®, Amor a Vida Produtos Naturais, Brazil); and WT group (which is drinking only white, Cha & Cia®, Brazil). The teas were prepared daily at 2.5% for infusion and offered to rats in an experimental situation as realized by Yang et al. (Eur J Cancer Prev, 12:391–395, 2003) e Niwattisaiwong et al. (Drug Metabol Drug Interact., 20:43-56, 2004). The rats were kept in plastic boxes (5 animals per box), under normal conditions, 12 hour light: 12 hour dark lighting schedule, with free access to beverage and food. This study was approved by ethics committee to be realized (numbers protocols 325 and 336). The experiment had last for three months, and in the end of each month, 10 animals of each group were superovulated with 150UI/Kg of eCG (Folligon®, Intervet Schering-Plough, Brazil) and 150UI/Kg of hCG (Vetecor®, Hertape Calier, Brazil) and sacrificed. The uteri were collected in Davidson solution and they were histologically analyzed by AgNor (Argyrophilic Nuclear Organizer Regions) method to detect endometrial cell proliferation. Photos of the uteri slides were taken at 1000x magnification and the areas of nuclear organizer regions (Nor) and nuclear areas were defined using software MOTIC Imageplus 2.0® (MOTIC, China), in 10 different camps of each slide, which 10 nucleus of were measured for camp, totalizing 100 cells for animal. The statistical analysis realized was ANOVA with Tukey, the differences were considered when P < 0.05. The endometrium of rats treated with teas presented minor ratio between nucleus and Nor compared to control in all moments analyzed (P < 0,0001): 30 days (CT = 4,81 ± 0,26a, GT = 3,38 ± 0,22b, WT = 1,44 ± 0,04c); 60 days (CT = 6,10 ± 0,42a, GT = 1,79 ± 0,03b, WT = 2,27 ± 0,40b); 90 days (CT = 6,45 ± 0,62a, GT = 1,92 ± 0,03b, WT = 3,25 ± 0,31b). The conclusion is the green and white teas consumption decreases the endometrial proliferation in rats. Financial support was provided by FAPESP (2010/20583-2).