National Food Research Institute, National Agriculture and Food Research Organization, 2-1-12 Kannondai, Tsukuba, Ibaraki 305-8462, Japan, 2-1-12 Kannondai, Tsukuba, Ibaraki 305-8462, Japan.
Curr Pharm Des. 2013;19(34):6148-55. doi: 10.2174/1381612811319340009.
Many previous epidemiological studies have revealed that green tea or green tea catechins contributed to the preveintion of lifestyle-related diseases. Several cohort studies on the relationship between green tea consumption and cardiovascular disease (CVD) risk/type 2 diabetes mellitus risk have been conducted. The results showed that green tea consumption (5 or more cups/day) was inversely associated with mortality from CVD and all causes. Within CVD mortality, the strongest inverse association was observed for stroke mortality. Furthermore, consumption of green tea, coffee, and total caffeine was associated with a reduced risk for type 2 diabetes. On the other hand, the analysis of randomized clinical trial (RCT) studies showed that the administration of green tea beverages or extracts resulted in significant reductions in serum total cholesterol and LDL-cholesterol concentrations, but had no apparent effect on HDL-cholesterol. Green tea reduced fasting blood glucose levels in a small intervention trial, although no improvements in HbA1c levels were seen. Continuous intake of green tea containing catechins and caffeine (5 or more cups per day) may be beneficial for body weight management, vascular disease risk reduction via LDL-cholesterol improvement, and type 2 diabetes risk reduction through the lowering of fasting blood glucose levels. Epigallocatechin-3-O-(3-O-methyl) gallate (EGCG3"Me) isolated from cv. "Benifuuki" green tea has been shown to strongly inhibit mast cell activation and histamine release after FcepsilonRI cross-linking through the suppression of tyrosine phosphorylation (Lyn) of cellular protein kinase, and the suppression of myosin light chain phosphorylation and high-affinity IgE receptor expression via the binding to 67 kDa laminin receptors. A double-blind clinical study on subjects with Japanese cedar pollinosis was carried out. At the eleventh week after starting intake, which was coincident with the most severe period of cedar pollen-scattering, symptoms such as nose blowing and eye itching were significantly relieved in the Benifuuki group compared with the placebo group. Six weeks of intake of Benifuuki green tea containing O-methylated catechins was useful for reducing some of the symptoms derived from Japanese cedar pollinosis, and did not affect any of the normal immune responses in the subjects with Japanese cedar pollinosis. Based on an investigation into the effects of the cultivars, tea seasons of crops and manufacturing methods, it was concluded that green or semi-fermented tea made from fully-matured Benifuuki in the second crop season should be consumed.
许多先前的流行病学研究表明，绿茶或绿茶儿茶素有助于预防与生活方式相关的疾病。已经进行了几项关于绿茶消费与心血管疾病 (CVD) 风险/2 型糖尿病风险之间关系的队列研究。结果表明，每天饮用 5 杯或更多杯绿茶与 CVD 死亡率和全因死亡率呈负相关。在 CVD 死亡率中，与中风死亡率的相关性最强。此外，绿茶、咖啡和总咖啡因的消耗与 2 型糖尿病风险降低有关。另一方面，对随机临床试验 (RCT) 研究的分析表明，饮用绿茶饮料或提取物可显著降低血清总胆固醇和 LDL-胆固醇浓度，但对 HDL-胆固醇没有明显影响。在一项小型干预试验中，绿茶降低了空腹血糖水平，尽管 HbA1c 水平没有改善。连续摄入含有儿茶素和咖啡因的绿茶（每天 5 杯或更多杯）可能有益于体重管理，通过改善 LDL-胆固醇降低血管疾病风险，通过降低空腹血糖水平降低 2 型糖尿病风险。从 cv.“Benifuuki”绿茶中分离出的表没食子儿茶素-3-O-(3-O- 甲基)没食子酸酯 (EGCG3"Me) 已被证明可通过抑制细胞蛋白激酶酪氨酸磷酸化 (Lyn) 以及通过与 67 kDa 层粘连蛋白受体结合来抑制肌球蛋白轻链磷酸化和高亲和力 IgE 受体表达，强烈抑制 FcepsilonRI 交联后的肥大细胞活化和组胺释放。对患有日本扁柏花粉症的受试者进行了一项双盲临床试验。在开始摄入后的第 11 周，恰逢扁柏花粉飞扬最严重的时期，与安慰剂组相比，Benifuuki 组的打喷嚏和眼睛瘙痒等症状明显缓解。6 周的 Benifuuki 含 O-甲基化儿茶素的绿茶摄入有助于减轻一些来自日本扁柏花粉症的症状，并且对患有日本扁柏花粉症的受试者的任何正常免疫反应都没有影响。基于对品种、作物茶季和制造方法的影响的调查，得出的结论是，应食用第二茶季完全成熟的 Benifuuki 制成的绿色或半发酵茶。
