Institute of Biology, College of Science, University of the Philippines, Diliman, Quezon City 1101, Philippines.
J Ethnopharmacol. 2011 Jan 27;133(2):613-20. doi: 10.1016/j.jep.2010.10.044. Epub 2010 Oct 28.
Crude extract of Uncaria perrottetii (A. Rich.) Merr. vinebark was evaluated for its immunomodulating activity in Balb/C mice. Initially, the immunomodulatory potential of the plant extract was evaluated using in vitro immune response assays at different concentrations of the plant extract (10 μg/mL, 20 μg/mL, 50 μg/mL and 100 μg/mL). Using the optimum concentration determined in the in vitro assays, the protective effect of the plant extract was assessed against drug-induced immunosuppression in vivo.
For the in vivo experiment, thirty-six (36) mice were divided into 3 groups of 12 mice each: (1) cyclophosphamide drug-induced (30 mg/kg BW) immunosuppressed mice (Cy group) served as the positive control; (2) Uncaria perrottetii extract and Cy-treated mice (U+Cy); and (3) PBS-injected mice as the negative control group [(-) CTRL].
The optimum concentration was determined to be 50 μg/mL in the in vitro assays. At this concentration, Uncaria perrottetii extract stimulated peritoneal phagocyte activation, produced a significant increase in the activity of phagocytic cells from the spleen and promoted splenic cellular proliferation with or without lipopolysaccharide (LPS) when compared with the PBS-treated cells (negative control). Moreover, cells treated with 50 μg/mL of Uncaria perrottetii increased macrophage respiratory burst activity that was comparable to that of the phorbol myristate acetate-stimulated splenic macrophages. In all immune assays undertaken in the in vivo experiment, the Cy-treated mice showed significantly lower response when compared with the PBS-treated mice. Significant improvement in peritoneal cell activation, phagocytic activity and cellular proliferation was exhibited by the U+Cy-treated mice when compared with Cy-injected mice. The extract from Uncaria perrottetii also significantly enhanced respiratory burst and plasma lysozyme activity compared with the Cy-injected mice.
Based on the results of both in vitro and in vivo trials, Uncaria perrottetii extract has immunopotentiating activities on the innate immunity of Balb/C mice and the extract could potentially reverse the immunosuppressive effects of Cy. However, the potential of the plant as source of bioactive products and metabolites for drug development still has to be fully investigated.
评估钩藤（A. Rich。） Merr. 藤皮的粗提取物在 Balb/C 小鼠中的免疫调节活性。最初，使用不同浓度的植物提取物（10 μg/mL、20 μg/mL、50 μg/mL 和 100 μg/mL）在体外免疫反应测定中评估植物提取物的免疫调节潜力。使用在体外测定中确定的最佳浓度，评估植物提取物对体内药物诱导的免疫抑制的保护作用。
对于体内实验，将 36 只（36）只小鼠分为 3 组，每组 12 只：（1）环磷酰胺药物诱导（30 mg/kg BW）免疫抑制小鼠（Cy 组）作为阳性对照；（2）钩藤提取物和 Cy 处理的小鼠（U+Cy）；和（3）PBS 注射的小鼠作为阴性对照组[（-）CTRL]。
在体外测定中确定最佳浓度为 50 μg/mL。在该浓度下，与 PBS 处理的细胞（阴性对照）相比，钩藤提取物刺激腹腔吞噬细胞活化，显著增加脾吞噬细胞的活性，并促进脾细胞增殖，无论是在脂多糖（LPS）存在下还是不存在 LPS 时。此外，用 50 μg/mL 钩藤提取物处理的细胞增加了巨噬细胞呼吸爆发活性，与佛波醇肉豆蔻酸乙酸刺激的脾巨噬细胞相当。在体内实验中进行的所有免疫测定中，与 PBS 处理的小鼠相比，Cy 处理的小鼠显示出明显较低的反应。与 Cy 注射的小鼠相比，U+Cy 处理的小鼠表现出明显改善的腹腔细胞活化、吞噬活性和细胞增殖。与 Cy 注射的小鼠相比，钩藤提取物还显著增强了呼吸爆发和血浆溶菌酶活性。
基于体外和体内试验的结果，钩藤提取物对 Balb/C 小鼠的固有免疫具有免疫增强作用，并且提取物可能逆转 Cy 的免疫抑制作用。然而，植物作为生物活性产品和代谢物来源用于药物开发的潜力仍有待充分研究。
