樱桃李多酚抗氧化活性及对肥胖小鼠肝脏的保护作用

该研究探讨了樱桃李多酚抗氧化活性及对肥胖小鼠肝脏的保护作用，为樱桃李果实的开发、利用提供理论基础。试验以醇提法获得樱桃李多酚为材料，在测定多酚含量基础上，测定提取物体外抗氧化活性。进一步建立肥胖小鼠模型，采用不同剂量多酚灌药处理，8周后，处死小鼠，取肝脏，计算肝脏指数，测定肝脏中TG浓度、T-CHO浓度、SOD活性、MDA浓度，荧光定量PCR测定炎症相关基因的表达。结果发现，樱桃李果实多酚提取物总多酚、总黄酮、总酚酸、总黄烷醇含量分别为439.17、186.37、168.27、68.86 mg/g，樱桃李总多酚含量较高，多酚中主要成分为黄酮类；DPPH自由基清除率为97.42%，FRAP法、ABTS法测得抗氧化活性分别为4.36 mmoL/mL、0.48 mmoL/mL Trolox，体外具有较强的抗氧化活性；多酚处理能显著降低肥胖小鼠肝脏TG，T-CHO、MDA含量，增加肝脏SOD含量，下调肝脏炎症因子IL-1β、TNF-α、IL-6基因表达。研究表明，樱桃李多酚能够提高抗氧化能力，减少高脂饮食引起的肝脏脂肪堆积和肝脏炎症，对小鼠肝脏具有保护作用。

Antioxidant Activities of Prunus cerasifera Polyphenols and Their Protective Effects on the Livers of Obese Mice

This study was aimed at evaluating the antioxidant activities of Prunus cerasifera polyphenols and their protective effects on the livers of obese mice, thereby providing a theoretical basis for the development and utilization of P. cerasifera fruits. First, polyphenols were obtained from P. cerasifera fruits via alcohol extraction. After polyphenol content determination, DPPH, FRAP, and ABTS methods were used to measure the in vitro antioxidant activities of the extracted polyphenols. Next, obese mice models were established and treated with different doses of polyphenols. After eight weeks of treatment, the mice were sacrificed to remove their livers. The liver index was calculated, and the TG, T-CHO, SOD, and MDA concentration in the livers were determined. Moreover, the expression levels of inflammation-related genes were measured via fluorescence quantitative PCR. The results revealed that the total polyphenol, flavonoid, phenolic acid, and flavanol contents in the extracted polyphenols were 439.17, 186.37, 168.27, 68.86 mg/g, respectively. Hence, the total polyphenol content in Prunus cerasifera is relatively high, and the main components are flavonoids. The corresponding DPPH free radical scavenging rate was 97.42%, and the antioxidant activities measured using the FRAP and ABTS methods were 4.36 mmoL/mL and 0.48 mmoL/mL Trolox, respectively, which indicates that the extracted polyphenols had strong in vitro antioxidant activities. Both low and high doses of polyphenols significantly reduced the TG, T-CHO, and MDA contents and enhanced the SOD activity in the livers of obese mice. Furthermore, the polyphenols down regulated the expression of the inflammatory factors interleukin-1 beta, tumor necrosis factor-alpha, and interleukin-6 in the liver tissues. These findings suggest that P. cerasifera polyphenols can improve the antioxidant capacity of the liver, reduce fat accumulation and liver inflammation induced by a high-fat diet, and protect the liver in mice.