永春佛手茶对溃疡性结肠炎小鼠的辅助保护功能及主要成分分析

Auxiliary Protective Effect of Yongchun Foshou Tea on Ulcerative Colitis in Mice and Analysis of Major Components Involved

为探讨永春佛手茶提取物对溃疡性结肠炎的保护功能和关键功效成分,本实验采用三硝基苯磺酸诱导建立急性溃疡性结肠炎小鼠模型,分别进行清香型、浓香型和陈香型永春佛手乌龙茶提取物灌胃干预(剂量均为200 mg/(kg·d)),研究不同香型永春佛手茶提取物对小鼠体质量、单位长度结肠质量和结肠组织病理情况,以及对小鼠血清白细胞介素(interleukin,IL)-6、IL-10、IL-1β、肿瘤坏死因子α(tumor necrosis factor α,TNF-α)质量浓度的影响。结果表明,与模型组相比,各干预组小鼠体质量、单位长度结肠质量和结肠组织均得到不同程度的改善,其中造模后5~7 d的浓香组和陈香组小鼠体质量相较于造模前无显著差异(P>0.05),清香组和浓香组小鼠单位长度结肠质量显著或极显著降低(P<0.05、P<0.01);不同香型永春佛手茶提取物均降低了小鼠结肠组织炎症程度,抗炎因子IL-10质量浓度均显著或高度显著增加(P<0.05、P<0.001),浓香组小鼠促炎因子IL-1β和IL-6水平显著下降(P<0.05)。对茶叶提取物主要生化成分和炎症因子的相关性分析发现,黄酮糖苷和N-乙基-2-吡咯烷酮取代的黄烷-3-醇类成分含量与3种促炎因子(IL-6、IL-1β和TNF-α)质量浓度呈负相关,茶氨酸、儿茶素类和黄酮糖苷含量与IL-10质量浓度呈显著正相关(P<0.05)。结论:不同香型永春佛手茶提取物对急性溃疡性结肠炎均有不同程度的改善作用,其中浓香型永春佛手茶提取物效果最为明显,可能是提取物中多酚类成分发挥了重要作用。

In order to explore the protective effect of Yongchun Foshou tea extracts on ulcerative colitis(UC) and the key bioactive compounds involved, we established a mouse model of UC induced by 2,4,6-trinitrobenzenesulfonic acid(TNBS) and intragastrically the mice with the water extracts of clean-aroma, strong-aroma and aged-aroma Yongchun Foshou oolong tea(200 mg/(kg·d)). We evaluated the effects of these three tea extracts on body mass, colon mass per unit length and pathological colon tissue as well as the serum levels of interleukin(IL)-6, IL-10, IL-1β, and tumor necrosis factor α(TNF-α) in mice with ulcerative colitis. Compared with the model group, body mass, colon mass per unit length, and pathological colon tissue were improved in the mice treated with each of the three tea extracts. There was no significant difference in body mass in the mice treated with the water extracts of strong-aroma and aged-aroma oolong tea for 5–7 days after UC induction compared with those before UC induction(P > 0.05). The mice treated with clean-aroma and strongaroma tea extracts showed a significant reduction in colon mass per unit length(P < 0.05 and P < 0.01). Each of these tea extracts reduced the degree of inflammation in mouse colon tissue, significantly increasing the concentrations of the antiinflammatory cytokine IL-10(P < 0.05 and P < 0.001). The concentrations of the pro-inflammatory cytokines IL-1β and IL-6 were significantly decreased in the mice treated with strong-aroma tea extract(P < 0.05). The correlation analysis of the major compounds in the tea extracts and inflammatory cytokines revealed that flavone glycosides and N-ethyl-2-pyrrolidinonesubstituted flavan-3-ols(EPSF) were negatively correlated with three pro-inflammatory cytokines(IL-6, IL-1β, and TNF-α). On the other hand, theanine, catechins, and flavone glycosides were significantly positively correlated with IL-10(P < 0.05). In conclusion, the water extracts of the three aroma types of Yongchun Foshou oolong tea have an ameliorative effect on acute ulcerative colitis. Strong-aroma tea extract is the most effective among these extracts, and the polyphenols in the extract may play an important role.