饲料中维生素D_3添加水平对黄鳝外周免疫相关组织细胞增殖和凋亡的影响

Effects of Vitamin D_3 Supplemental Level on Cell Proliferation and Apoptosis of Peripheral Immune Related Tissues in Monopterus albus

本试验旨在探索维生素D3添加水平对黄鳝(Monopterus albus)外周免疫相关组织细胞增殖和凋亡的影响。挑选体质健康、平均体重为(21.7±2.1)g的黄鳝360尾,随机分为6组,每组2个重复,每个重复30尾。6组黄鳝分别饲喂在基础饲料中添加0(对照)、250、500、1 000、2 000和4 000 IU/kg维生素D3的试验饲料。试验期60 d。饲养试验结束后,从各组随机选择6尾黄鳝,分别采集其肝胰脏、脾脏、头肾和后肠组织,采用流式细胞术检测样品细胞的增殖和凋亡情况。结果表明:饲料中维生素D3添加水平对脾脏、后肠和头肾3种组织细胞增殖和凋亡的影响变化趋势基本一致,即1 000 IU/kg组细胞增殖指数(PI)最高,凋亡指数(AI)最低,与对照组和4 000 IU/kg组差异显著(P<0.05)。肝胰脏细胞PI随饲料中维生素D3添加水平的增加而降低,以4 000 IU/kg组最低,显著低于对照组(P<0.05);肝胰脏细胞AI以1 000 IU/kg组最低,显著低于对照组和4 000 IU/kg组(P<0.05)。由此得出,饲料中添加1 000 IU/kg维生素D3可降低黄鳝外周免疫相关组织细胞凋亡,促进脾脏、头肾和后肠细胞增殖,有利于外周淋巴器官生长;饲料中添加4 000 IU/kg维生素D3可致黄鳝外周免疫相关组织细胞增殖受阻,细胞凋亡加快,引起机体免疫功能抑制。

This experiment was conducted to study the effects of vitamin D3 supplemental level on cell proliferation and apoptosis of peripheral immune related tissues in Monopterus albus. A total of 360 healthy M. albus with an average body weight of （21.7？2.1） g were randomly assigned to 6 groups with 2 replicates per group and 30 M. albus per replicate. The M. albus in the 6 groups were fed the basal diet supplemented with 0 （control）, 250, 500, 1 000, 2 000 and 4 000 IU/kg vitamin D3, respectively. The experiment lasted for 60 days, and the hepatopancreas, head kidney, spleen and hindgut of 6 M. albus in each group were collected after feeding experiment. The proliferation and apoptosis of cells in each sample were tested by flow cytometry. The results showed as follows： the change trends of the cell proliferation and apoptosis of spleen, hindgut and head kidney tissues were basically identical with the vitamin D3 supplemental level increasing, which presented as the 1 000 IU/kg group had the highest cell proliferating index （PI） and the lowest cell apoptotic index （AI）, and there were significant differences between 1 000 IU/kg group and control group, 4 000 IU/kg group （P〈0.05）. The PI of hepatopancreas cells was decreased with the increase of vitamin D3 supplemental level, and the lowest PI was found in 4 000 IU/kg group, in which the cell PI was significantly lower than that in the control group （P〈0.05）. The lowest AI of hepatopancreas cells was found in 1 000 IU/kg group, in which the cell AI was significantly lower than that in control group and 4 000 IU/kg group （P〈0.05）. It can be concluded that 1 000 IU/kg vitamin D3 supplementation reduces the cell apoptosis of peripheral immune related tissues, promotes the cell proliferation of head kidney, spleen and hindgut, and it is beneficial for the development of peripheral lymphoid organs in M. albus; 4 000 IU/kg of vitamin D3 supplementation hinders the cell proliferation and accelerates the cell apoptosis of peripheral immune related tissues, and induces the inhibition of immune function in M. albus.