Preparation of Lateolabrax maculatus Immune Peptides and Its Bidirectional Immunomodulatory Activity on RAW264.7 Cells(海鲈鱼免疫肽的制备及对RAW264.7细胞双向免疫调节作用研究)
摘要
To study the immune and anti-inflammatory activities of Lateolabrax maculatus immunomodulatory peptides (LIP), the preparation conditions of LIP were optimized by single factor experiments and response surface methodology with the stimulation index of mouse spleen lymphocytes as an indicator. RAW264.7 macrophage model was used to study the immunomodulatory effect of LIP, and anti-inflammatory activity of LIP was explored by constructing a lipopolysaccharide-induced RAW264.7 macrophage inflammatory model. The results showed that the optimal preparation conditions for LIP were as following:solid-liquid ratio 1.0∶3.8 (g/mL), enzyme adding amount 2.14%, papain hydrolysis time 56min. Under this condition, the stimulation index of mouse spleen lymphocytes reached 2.57. The results of macrophage immunoactivity show that LIP exerted immunomodulatory activity. 400μg/mL LIP exerted immunomodulatory effects by promoting the proliferation and phagocytosis capacity, nitric oxide and reactive oxygen species production, nitric oxide synthase (iNOS) mRNA expression, and proinflammatory cytokines secretion. Moreover, 400g/mL LIP also showed effectively anti-inflammatory capacity by downregulating prostaglandin E<sub>2</sub> and proinflammatory cytokines, and reducing excessive secretion of NO via inhibiting overexpression of iNOS and cyclooxygenase-2 mRNA. These results suggested that LIP exerted bidirectional immunomodulatory activity,including “increasing immune response” and “inhibiting excessive immune response”, which provided a theoretical basis for bidirectional immunomodulatory functional foods research.(为探究海鲈鱼免疫调节肽(Lateolabrax maculatus immunomodulatory peptides,LIP)的免疫和抗炎活性,以小鼠脾淋巴细胞刺激指数为指标,通过单因素和响应面优化实验确定LIP的最佳制备条件。利用RAW264.7巨噬细胞模型,探究LIP的免疫调节活性。并构建脂多糖诱导的RAW264.7巨噬细胞炎症模型,探讨LIP的抗炎活性。研究结果表明,LIP的优化制备条件为料液比1.0∶3.8(g/mL)、酶质量分数2.14%、木瓜蛋白酶酶解时间56min,此条件下的LIP对小鼠脾淋巴细胞刺激指数为2.57。巨噬细胞免疫活性研究结果表明,LIP具有良好的免疫调节作用。当LIP质量浓度为400μg/mL时,LIP主要是通过促进了RAW264.7细胞的增殖活性、吞噬能力、一氧化氮和胞内活性氧的生成、一氧化氮合酶表达以及促炎因