Tea Research Institute, Guangdong Academy of Agricultural Sciences, Guangdong Key Laboratory of Tea Resources Innovation & Utilization, Guangzhou 510640, China.
Department of Tea Science, College of Horticulture, South China Agricultural University, Guangzhou 510641, China.
Nutrients. 2022 Feb 24;14(5):972. doi: 10.3390/nu14050972.
Liver injury is a life-threatening condition that is usually caused by excessive alcohol consumption, improperdiet, and stressful lifestyle and can even progress to liver cancer. Tea is a popular beverage with proven health benefits and is known to exert a protective effect on the liver, intestines, and stomach. In this study, we analyzed the therapeutic effects of six kinds of tea on carbon tetrachloride (CCl)-induced liver injury in a mouse model. The mice were injected with 10 mL/kg 5% CCl to induce liver injury and then given oral gavage of green tea, yellow tea, oolong tea, white tea, black tea, and dark tea, respectively. The serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured, and the expression levels of inflammation and oxidative stress-related proteins in the liver tissues were quantified. All six kinds of tea partly reduced the liver index, restored the size of the enlarged liver in the CCl model, and decreased the serum levels of ALT and AST. Furthermore, the highly fermented dark tea significantly reduced the expression levels of NF-κB and the downstream inflammatory factors, whereas the unfermented green tea inhibited oxidative stress by activating the antioxidant Nrf2 pathway. Taken together, tea can protect against liver inflammation, and unfermented tea can improve antioxidant levels. Further studies are needed on the bioactive components of tea to develop drugs against liver injury.
肝损伤是一种危及生命的疾病，通常由过度饮酒、不当饮食、压力过大的生活方式引起，甚至可能进展为肝癌。茶是一种受欢迎的饮料，具有经过证实的健康益处，已知对肝脏、肠道和胃具有保护作用。在这项研究中，我们分析了六种茶对小鼠模型中四氯化碳（CCl）诱导的肝损伤的治疗作用。将小鼠注射 10 mL/kg 的 5% CCl 以诱导肝损伤，然后分别给予绿茶、黄茶、乌龙茶、白茶、红茶和黑茶灌胃。测量血清丙氨酸氨基转移酶（ALT）和天冬氨酸氨基转移酶（AST）水平，并定量测定肝组织中炎症和氧化应激相关蛋白的表达水平。六种茶都部分降低了肝指数，恢复了 CCl 模型中肿大的肝脏大小，降低了 ALT 和 AST 的血清水平。此外，高度发酵的黑茶显著降低了 NF-κB 及其下游炎症因子的表达水平，而未发酵的绿茶通过激活抗氧化 Nrf2 通路抑制氧化应激。综上所述，茶可以预防肝脏炎症，未发酵的茶可以提高抗氧化水平。需要进一步研究茶的生物活性成分，以开发针对肝损伤的药物。
