جستجوی مقالات مرتبط با کلیدواژه « green tea » در نشریات گروه « علوم پایه »

The incidence of heart disease increases with age. Green tea is an antioxidant that can prevent cellular senescence. Mitochondria play a vital role in the intracellular pathway of apoptosis. Bax and bcl-2 proteins are the main regulators of mitochondrial apoptosis. Thus, the present study is aimed at investigating the effect of 12 weeks of green tea extract consumption on expression Bax and bcl-2 genes of old rats’ heart tissue in response to acute exhaustive exercise. Thirty-two male rats were randomly assigned to two groups of supplement and non-supplement, each consisting of 16 rats. The supplement group received green tea extract for 12 weeks. At the end of the 12 weeks, each of these groups was further divided into two groups of rest and acute exhaustive exercise. The non-supplement with the rest group was called the control group. The non-supplement with exercise group was called exercise group, the supplement group with rest was called the supplement group and finally, the last group was entitled to supplement with exercise. After 12 weeks of taking green tea extract, one session of the acute exhaustive exercise was held on the treadmill. The real-time PCR method was used to measure the expression of Bax and bcl-2 genes. The results showed that 12 weeks of green tea extract consumption significantly reduced Bax gene expression and Bax to bcl-2 gene expression ratio and significantly increased cardiac tissue bcl-2 gene expression in response to acute exhaustive exercise. About acute exhaustive exercise session, it significantly increased Bax gene expression and Bax to bcl-2 gene expression ratio as well as significantly decreasing bcl-2 gene expression in heart tissue. The study concludes that 12 weeks of green tea extract can reduce Bax gene expression and Bax to bcl-2 gene expression ratio and significantly increase cardiac tissue bcl-2 gene expression at rest and after acute exhaustive exercise

Gastric cancer is second leading cause of cancer related death in the world. Use of herbal drugs because of having fewer side effects is of importance. The anticancer effects of catechin polyphenols in green tea have key role in promoting cancer cells to apoptosis. The aim of this study is to determine the changes in the expression rate of Bax and Bcl_2 genes in AGS cells after treatment with green tea extract.

Concentrations of 800, 1200, 2000  μg /ml of Green Tea extraction were treated in AGS cells as two groups 48 and 72 hours. Extraction of  RNA, synthesis of cDNA and the study of genes expression was performed by Real time PCR and also GAPDH gene was used as reference gene.

The results of Real time PCR data analysis by 2- Ct method shows significant increase expression rate of  Bax / Bcl_2 genes in doses of 800, 1200 and 2000 μg / ml for times of 48 and 72 hours.

Green tea is the reason of increasing Bax/Bcl_2 ratio which it is dependent to concentration and time, and it can lead cancerous cell to programed cell death. This extract can be useful in the treatment of gastric cancer for patients with this cancer. To clarify the effective molecules and their mechanisms, further studies are undertaken on animal models and humans.

Green tea (Camellia sinensis) was considered effective medicine for treating different ailments in ancient Asian folk medicine. It is known for its abundance of antioxidants. Polycystic ovary syndrome (PCOS) is a prevalent endocrinological disorder in reproductive-age women and is often associated with metabolic syndrome. The purpose of the study, the effect of green tea extract on letrozole-induced oxidative stress was investigated on levels of sex hormones of adult female Wistar rats.

In this study, a total of 48 female rats were randomly divided into 8 groups of 6: The normal control group (intact), the healthy experimental group (green tea extract 50, 100 and 200 mg/kg bw, gavage), PCOS control group (letrozole 1 mg/kg bw, gavage), PCOS experimental group (green tea extract 50, 100 and 200 mg/kg bw together letrozole). The animals were euthanized 24 h after the last dose of the treatment on day 29. Blood was immediately obtained after the animals were sacrificed. The serum was used to assay the levels of testosterone, estradiol, FSH and LH.

Our results showed that administration of letrozole significantly increased the levels of testosterone, estradiol, LH and decreased FSH. The results study showed that green tea extract treatment significantly decreased the levels of testosterone, estradiol, LH and increased FSH in PCOS experimental group.

These results provide data supporting the potential clinical use of green tea extract for the treatment of PCOS.

Despite of innumerable potentials of Iran TeaIndustry(ITI) it could not stabilized his production,commerce and processing position in global tea industry.There exist more than 60000 families that involving withITI then codification of ITI strategy and appropriatestructure of that is vital subject to study. The current study has determined weakness, opportunity, threat andstrength of tea industry.Tea is one of the strategic products of the north of the country with a 120-yearhistory. The area under cultivation in Iran is about32,000 hectares, located in more than 900 villages in thecities of Somesara, Fouman, Shaft, Rasht, Lahijan,Astana Ashrafieh, Siahkal, Langrood, Roodsar andAmlash in Guilan province and the cities of Ramsar andTonekabon up to Chalus. The province of Mazandaran has been sporadically disrupted for about 200 kilometers,separated by low and high distances and close to themain road, and now has about 60,000 households incultivation and 8,000 households in the process ofprocessing 183 tea factories, are working. Tea is a perennial and immaculate plant native to Southeast Asiaand its most important commercial species is Camellia.Black and green tea is the most common form of teaproduction in the world and the largest producers areChina, India and Kenya.

In the study , synergistic effect of green tea (camellia sinesis) extract and treadmill aerobic exercise on wound healing in streptozotocin induced diabetic mice has been investigated.  

The number of 50 male mice with the approximately weight of 30-35 gram health and adult are put in 5 groups: non diabetic – immobile , diabetic - immobile, diabetic exercise - diabetic and  immobile with green tea extract , diabetic with synergism of exercise and green tea extract. After inducing of diabetes using sterptozotocin mice were killed and in days 3-7-14-21 macroscopic and histopathologic analysis were performed.  

The results indicated that in synergistic group of  green tea extract and treadmill exercise , wound area decreased and fibroblast  increased after 7 days significantly compared with other groups (p<0.001).PMN cells decreased after 3 days significantly compared with other groups (p<0.001).  

The results suggest that green tea extract and treadmill exercise have synergistic effect on wound healing in diabetic mice.

Inroduction & Gastric cancer is second leading cause of cancer related death in the world. Use of anticancer herbal drugs because of having fewer side effects is of importance. green tea is one of herbal medicines which contain anticancer effect.The aim of this study has been to investigating changes in gene expression of HER-2 in green tea treated human AGS adenocarcinoma cells lines.
Material and AGS cells were treated with the aqueous extract of green tea in different concentrations including 800,1200 and 2000 μg/ml. After 48 hrs and 72hrs treatment, RNA extraction has been done. Following cDNA synthesis, the rate of expression of HER-2 gene was evaluated using Real time PCR.
The over expression of HER-2 gene has been shown in 800 μg/ml of green tea extract. In dose of 1200 μg/ml and 2000 μg/ml of green tea extract significant reduction in HER-2 gene have been shown and the most reduction has been observed in 72 hours treatment and the concentration of 2000 μg/ml green tea extract.
Green tea extract in high concentrations, is the reason of decreasing the rate of HER2 gene expression and this factor can prevent the development and progression of gastric cancer cells.

The use of exercise along with herbal supplements is one of the proposed methods for controlling obesity and the complications of obesity, since there are variety of training programs and plant material. However, their exact efficacy is not yet clearly proven. Therefore, the aim of this study was to investigate the effects of aerobic training and green tea supplementation on heart rate and blood pressure among overweight. Thirty overweight healthy female subjects were selected in the age range of 35-25 years. Then, after similarization the groups based on body mass index (BMI) and age, they randomly named to one of three groups: aerobic exercise follow supplementation with green tea group (N=10), green tea supplementation group only (N=10), and exercise group were just aerobics (N=10). Aerobic exercises have been done for 7 weeks in 3 times per week and green tea supplementation was consumed during seven weeks in three times a week in the amount of 2 g after meals. Before and after the intervention period, heart rate, blood pressure and weight of the subjects were measured. One-way ANOVA were used. The results showed that systolic blood pressure follow aerobic training program combined with supplementation of green tea significantly reduced. However, heart rate was reduced in the aerobic exercise group only compared to the green tea supplement group.

The aim of the present study was to stereological evaluate the protective effect of green tea extract on the morphological changes of seminiferous tubules following sodium arsenite exposure in mice. 24 adult male NMRI mice were randomly divided into four groups including control، sodium arsenite (5mg/kg/day)، green tea extract (100 mg/kg/day) and finally sodium arsenite+green tea extract. Mice were (orally) treated for 34 days. At the end، mice were sacrificed and their right testis were taken out، fixed، processed and stained with heidenhain'' azan method. The morphological and changes of testicular tissue was examined using stereological methods. Data were analyzed using one way ANOVA and means difference was considered significant at P<0. 05. Sodium arsenite treatment caused a significant decrease in the mean seminiferous tubules diameter (p<0. 008)، germinal epithelium height (p<0. 001) and the basement membrane thickness (p<0. 011) as well as in the number of spermatocyte (p<0. 003)، round spematid (p<0. 028)، long spermatid (p<0. 011) and sertoli (p<0. 03) cells compared to the control group. The above changes increased to the control level in sodium arsenite+green tea exteract group. The results indicate that green tea extract may be useful in reducing the toxic effects induced by sodium arsenite.

Aquaporin4 (AQP4) is the main water channel in the brain that has important role in water transport across blood- brain- barrier. It has been proved that intracranial pressure and also expression of AQP4 increase in some disorders such as Hydrocephalus, Hyponatremia, cytotoxic oedema and brain tumours and drugs that can decrease the expression of this AQP can offer some treatment for these disorders. The aim of this study was to determine whether green tea extract (GTE) can down regulate the Aquaporin4 protein level in brain cortex. This research is a laboratory experimental study. 40 Wister rats (4-6 weeks) were randomly divided into 4 groups as follows: untreated control group, sham group treated intra peritoneally (IP) with 200 μl saline (solvent GTE), experimental1&2treated IP with 100& 200 mg/kg GTE dissolved in 200 μl saline. After 6 hours, expression of AQP4 in control, sham, and experimental groups were tested by immunohistochemistry and western blotting. Results from immunohistochemistry and western blotting showed that GTE can down regulate the AQP4 expression level on dose-dependent manner in brain cortex. It is suggested that GTE has potential to reduce the level of AQP4 protein in brain cortex and it can be useful as a herbal medicine to reduce intracranial pressure in diseases such as hyponatremia, cytotoxic oedema, brain tumours and etc.