Green Tea and its Effect on Hemostasis Measured by Thrombelastography

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1 10 AMJ March, 2015 Green Tea and its Effect on Hemostasis Measured by Thrombelastography Bryant Alyzandyr Eumhyn Chua 1, Trully D. Sitorus 2, Nadjwa Zamalek D. 3 1 Faculty of Medicine, 2 Department of Pharmacology and Therapy, Faculty of Medicine, Universitas Padjadjaran, 3 Department of Clinical Pathology, Faculty of Medicine, Universitas Padjadjaran /Dr. Hasan Sadikin General Hospital Bandung Abstract Background: Increasing health problems may come from changes in lifestyle including stressful lifestyles, high calorie diets, and lack of physical activity. Those may also lead to an increase occurrence of abnormal hemostasis. Green tea has been well known for its many benefits, including its antithrombotic effect. The aim of this study was to determine whether the consumption of green tea actually affects hemostasis and to measure changes in hemostatic parameters after its consumption. Methods: A preliminary explorative study was conducted on 3 healthy female subjects aged between 21 to 22 years old for 8 weeks from October to November 2012 in Jatinangor, Sumedang, Indonesia. The subjects were subjected to initial thrombelastography analysis and started drinking green tea twice a day after meals. The solution was made by steeping a teabag in 250ml water of 70 C for 2 minutes. After 8 weeks, another thrombelastography analysis was performed to the subjects. Results: Pre- and post-intervention results of the analysis were averaged and compared according to the parameters. The results of this study showed prolonged R (Reaction-time) and K (K-time), decreased α (angle) and MA (Maximum Amplitude), and increased LY30 (lysis at 30 minutes), showing an overall reduction in coagulability. Conclusions: The consumption of green tea twice a day for 8 weeks affects hemostasis with hemostatic parameters measured by thrombelastography show differences before and after consumption. Keywords: Green tea, hemostasis, thrombelastography Introduction The prevalence cardiovascular diseases are increased in the worldwide including Indonesia due to the changes of lifestyle. This situation results in an increased risk of artherosclerosis which leads to thrombosis. 1,2 Thrombosis is a pathological term for the formation of a blood clot (thrombus) inside a blood vessel. This condition involves disruption of hemostasis including composition of blood (hypercoagulability), quality of vessel wall (endothelial injury) or nature of blood flow(stasis). 3,4 The prevention of thrombosis or the abnormalities in hemostatic parameters can provide a protective benefit to those known to be at risk of cardiovascular diseases, especially coronary heart disease and stroke. A cheaper and safer solution to the problem is the use of traditional medicine as an alternative medicine. 5 Tea or scientifically known as camellia sinensis is vastly grown all over the terrains of Indonesia. It is also affordable and widely available. There are many variety of tea such as: green tea, black tea, and oolong tea. Green tea is made from the tea leaves which undergo minimal oxidation by being immediately heated with either steam heat or dry heat. 6 This method of processing enables the preservation of beneficial properties of its polyphenols in the form of flavonoids like catechins and epigallocatechingallate (EGCG), chlorogenic acid and coumarylquinic acid, theogallin (3-galloylquinic acid), theanine (5-N-ethylglutamine), and also small amounts Correspondence: Bryant Alyzandyr Eumhyn Chua, Faculty of Medicine, Universitas Padjadjaran, Jalan Raya Bandung- Sumedang Km.21, Jatinangor, Sumedang, Indonesia, Phone: alyzandyr@gmail.com

2 Bryant Alyzandyr Eumhyn Chua, Trully D. Sitorus, Nadjwa Zamalek D: Green Tea and its Effect on Hemostasis Measured by Thrombelastography 11 of caffeine and other common methylxanthines, theobromine and theophylline. Green tea has many notable benefits, including its role in reducing the risk for cardiovascular diseases. 7 This was a preliminary study since only a few in depth studies have been conducted on the effect of green tea by using hemostasic parameters as an antithrombotic affect. The aim of this study is to determine whether the consumption of green tea actually affects hemostasis or to measure changes in hemostatic parameters after consumption. Methods A preliminary explorative study was conducted to determine the changes in hemostasis by interpreting thrombelastography patterns in human beings before and after 8 weeks consumption of green tea. This study was conducted over the period of October November 2012 in Jatinangor, Sumedang, Indonesia. The subjects of this study were 3 healthy female students, aged between 21 to 22 years old. The selected subject was considered to be healthy by the following criterias: passed as healthy after undergoing a general physical examination by a certified doctor with normal BMI, nonsmoker, non-alcoholic, consumes a proper and balanced diet daily, and has no history of cardiovascular diseases or hematologic disorders. The subject signed an informed consent form and agreed to follow the routine of green tea consumption for the whole period of study until completed. The green tea used in this research is in the form of packaged tea bags. The tea bags contain green tea leaves which are planted and produced in Central Java, Indonesia. Data and characteristics of the subject were also recorded. The green tea solution was prepared each time before consumption with the following procedures: 1) Water was heated in a kettle at about 70ºC and a thermometer was used to monitor the temperature.8,9 2) 250 ml of hot water was measured using a measuring beaker and transferred to a mug 3) a green tea bag was soaked in the hot water, 4) the green tea was steeped in the hot water for 2 minutes.9, 5) then the tea bag was taken out and the preparation was ready to be consumed. The whole green tea infused water was consumed by the subjects after meals every morning and evening for 8 weeks continuously. A checklist or drinking schedule was also provided to facilitate the subjects to ensure that they would drink regularly according the schedule. Blood specimens from the subjects were collected at least 1 week after the first day of their menstruation periode to avoid bias due to the physiologic clotting process. Blood was withdrawn twice, before and after 8 weeks of green tea consumption. The procedures were as follows 10 : 1) body temperature is taken for 5 minutes to set the analyzer temperature according to the subject s temperature, 2) 2ml of blood was withdrawn from the subject at the superficial vein of the arm, 3) 0.36 ml was then taken from the sample and placed into a pre-warmed cuvette, 4) then the cuvette was then rotated gently and a sensor shaft/pin was inserted into the cup, 5) the blood in the cuvette was allowed to clot upon rotation, 6) the coagulation was detected by the sensor shaft/pin and the profile is displayed by the computer, 7) The pattern shown was printed and recorded. The data was then compared based on R (Reaction-time), K (K-time), α (angle), MA (Maximum Amplitude) and LY30 (lysis at 30 minutes) to determine the hemostatic change(s) Results Most of the subject showed several changes in all parameters but still in normal range, except in subject 1, there was an increased in LY30(%) from normal to high range (Table 1). The average R time was prolonged to its normal limits as compared to the previous, as the average time changed from 8.6 min to 10.0 min. The K time was prolonged within its normal limits, as it showed an average change from 2.9 min to 3.1 min. The α parameter generally decreased within the normal range from an average of 52.6 degrees to 51.9 degrees. The average MA values also decreased from a high value of 64.8 mm to 57.0 mm which was within its normal range. The LY30 parameter showed a general increase within the normal range, which was from 1.3% to 5.37% on average (Table 2). Discussions Initial results of the thrombelastography (TEG) analysis showed hypercogulation in Subject 1. It was caused by the subject s genetic predisposition to have a hypercoagulable condition and increased hemostatic activation.

3 12 AMJ March, 2015 Table 1 Thrombelastograph Pattern Pre & Post Green Tea Consumption Study Subject /Parameters Subject 1 Thrombelastography Results Pre Post Changes R (min) Decreased but remained in low range K (min) Increased but remained in normal range α (deg) Decreased but remained in normal range MA (mm) Decreased from high to normal range LY30 (%) Increased from normal range to high Subject 2 R (min) Increased from low to normal range K (min) Increased but remained in normal range α (deg) Decreased but remained in normal range MA (mm) Decreased but remained in normal range LY30 (%) Decreased but remained in normal range Subject 3 R (min) Increased but remained in normal range K (min) Decreased but remained in normal range α (deg) Increased but remained in normal range MA (mm) Borderline high in normal range LY30 (%) Increased but remained in normal range *R: Reaction Time; K: K-time; α: α Angle; MA: Maximum Amplitude; LY30: Lysis at 30 minutes * Normal Values: R: 9-27; K: 2-9; α: 22-58; MA: 44-64; LY30: 0-8 The initial blood test conducted on the blood of Subject 2 also showed an inclination towards hypercoagulation. This may have also been related to her familial genetics which would lead to continuous hemostasis activation. Subject 3 was also reported having an inclination towards hypercoagulation although all parameters were in normal limits. Related to the characteristics of subject history, it is also found that her family had a history of heart related conditions. The result of the post green tea drinking Table 2 Pre & Post Comparison of the Average Thrombelastography Results According to Parameter Parameters Average Thrombelastography Results Pre Post General Changes R (min) Prolonged to normal range K (min) Prolonged within normal range α (deg) Decreased within normal range MA (mm) Decreased to normal range LY30 (%) Increased within normal range *R: Reaction Time; K: K-time; α: α Angle; MA: Maximum Amplitude; LY30: Lysis at 30 minutes * Normal Values: R: 9-27; K: 2-9; α: 22-58; MA: 44-64; LY30: 0

4 Bryant Alyzandyr Eumhyn Chua, Trully D. Sitorus, Nadjwa Zamalek D: Green Tea and its Effect on Hemostasis Measured by Thrombelastography 13 showed that drinking of green tea for 8 weeks gave changes to the thrombelastography parameters among the study subjects. The most obvious change was seen in Subject 1 who had a low R time and a high LY30, and was reported having primary fibrinolysis. This condition was probably because of the initial hypercoagulation which has overcome the fibrinolysis process. However, after drinking green tea, the coagulation process was reduced thus enabling the fibrinolysis to be more apparent in the post-test results. On the other hand, subject 2 and 3 had all their parameters within normal ranges as shown in their post-test thrombelastography results. It showed that the parameters which were outside of the normal ranges have returned to their physiologic values. The findings from all three subjects may point out the possible effect of green tea in reducing hypercoagulable conditions. The changes can be observed in all of the main parameters by comparing of the averaged pre and post results (Table 2). The comparison of R pointed out a prolongation of reaction time from a shorter than normal time average to an average within the normal range. The time taken for initial fibrin formation increased and showed that there was a reduction in hypercoagulation and also a decreased tendency for hypercoagulation after drinking green tea. K also demonstrated that showed a prolongation in terms of average K-time, meaning that the speed for the clot to reach certain strength was longer than the previous one. This showed an overall increase in the time for the development of a clot. Although the shortened time was still within the normal physiological range, it indicated a reduced coagulation. As for α, which is the measure of clot strengthening, the results showed a decrease in the average value between pre and post analysis. Although the values remained within the normal range, this also indicated a reduction in the process of coagulation. From the results obtained, MA showed a decrease of ultimate strength of the fibrin clot, from a slightly higher than normal value to a value within the normal limits after the drinking of green tea. Therefore, that platelet function/ aggregation was reduced which indicated a reduced tendency for hypercoagulation. The last parameter compared was LY30, the percentage of lysis after 30 minutes. The comparison among the average percentages for LY30 showed increased of clot lysis. This could have indirectly meant that there was an elevation in the compensatory mechanism to lyse the end-product of clot formation. There is no direct comparison to previous researches because no study has been conducted in the same ways, involving the use of thrombelastography analysis. However, there were similar studies conducted to measure the effect of green tea consumption on human health. One of them is a prospective cohort study conducted by Kuriyama et al. 11 This study was conducted for 11 years starting in 1994 among Japanese adults aged 40 to 79 years old. The researchers found that green tea consumption was associated with reduced mortality due to cardiovascular diseases. 11 Besides, a few other studies and journals have suggested the possible theories about the effect of green tea on cardiovascular health which is related to the anti-platelet and anti-thrombotic activity of green tea such as the inhibition of calcium increase; inhibition of acetyl-coa:lysopafacetyltransferase; and suppression of arachidonic acid release and 12, 13 thromboxane A2 synthase activity. It concludes that the consumption of green tea twice daily for 8 weeks affects hemostasis. Moreover, the hemostatic parameters measured by thrombelastography showed differences before and after consumption in terms of: prolonged R and K, decreased α and MA, and increased LY30. This study has several limitations such as inclusion for the subjects were limited due to lack on funding. It is recommended from this study that further research should be conducted involving a larger sample with the use of statistical analysis to obtain results of greater significance. Moreover, bio molecular research should be conducted to determine the precise mechanism in which green tea affects hemostasis and to know the optimal dosage of consumption. References 1. Khor GL. Cardiovascular epidemiology in the Asia Pacific region. Asia Pac J Clin Nutr. 2001:10(2): Ng N, Stenlund H, Bonita R, Hakimi M, Wall S, Weinehall L. Preventable risk factors for noncommunicable diseases in rural Indonesia: prevalence study using WHO STEPS approach. Bull World Health Organ.2006; 84(4): Harmening DM. Clinical hematology and the fundamentals of hemostasis. 5th ed. Philadelphia: F. A. Davis Co; p

5 14 AMJ March, Malone PC, Agutter PS. The aetiology of deep venous thrombosis: a critical, historical and epistemiological survey. Netherlands:Springer; p Miller KL, Liebowitz RS, Newby LK. Complementary and alternative medicine in cardiovascular disease: a review of biologically based approaches. Am Heart J. 2004;147(3): Cabrera C, Artacho R, Gimenez R. Beneficial effects of green tea--a review. J Am Coll Nutr. 2006;25(2): Tanner L. Study unclear on green tea as a barrier to two big killers [downloaded in 17 April 2012]. Available from: nationworld/ci_ Dorman K. What is the difference between brewing tea & steeping tea? [Online Article] [Downloaded in 12 May 2012] Available from: livestrong.com/article/ whatis-the-difference-between-brewing-teasteeping-tea/. 9. Paajanen S. Tea brewing temperature guide. [Online Article] [downloaded in 12 May 2012] Available from: coffeetea.about.com/od/teabrewing/a/ teatemp.htm. 10. Wenker O, Wojciechowski Z, Sheinbaum R, Zisman E. Thrombelastography. The Internet Journal of Anesthesiology. [Online Journal] 1996;1(3). [downloaded in 18 April 2012]. Available at: com/ija/1/3/11391# 11. Kuriyama S, Shimazu T, Ohmori K, Kikuchi N, Nakaya N, Nishino Y, et al. Green tea consumption and mortality due to cardiovascular disease, cancer, and all causes in Japan. JAMA. 2006;296(10): Kang WS, Chung KH, Chung JH, Lee JY, Park JB, Zhang YH, et al. Antiplatelet activity of green tea catechins is mediated by inhibition of cytoplasmic calcium increase. J Cardiovasc Pharmacol. 2001;38(6): Velayutham P, Babu A, Liu D. Green tea catechins and cardiovascular health: an update. Curr Med Chem. 2008;15(18):