Endotoxemia-induced lymphocyte apoptosis is augmented by a hyperinsulinemic-euglycemic clamp
Endotoxemia-induced lymphocyte apoptosis is augmented by a hyperinsulinemic-euglycemic clamp
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DOI：
10.1097/00000542-200504000-00012
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发表时间：
2005-04-01
期刊：
影响因子：
8.8
通讯作者：
Tonnesen, E
中科院分区：
文献类型：
--
作者：
Nielsen, JS;Larsson, A;Tonnesen, E
背景：脓毒症和内毒素血症与淋巴细胞凋亡有关。这被认为是有害的，有助于在已经免疫受损的患者中进一步抑制免疫。由于血糖正常化可改善危重患者的预后，作者推测胰岛素和降血糖的作用之一是抑制淋巴细胞凋亡。因此，在猪的这项实验研究中，作者研究了急性内毒素血症和高胰岛素-正葡萄糖钳夹（HEC）对淋巴细胞凋亡的单独和联合作用。稳定60 min后，38只麻醉和机械通气的猪（体重，35-40 kg）被分成（通过在实验前进行的随机化）四组，然后研究570 min。第2组接受HEC（5 mm p-葡萄糖，胰岛素输注速率为0.6 mU中心点kg（-1）中心点min（-1））570 min。第3组接受脂多糖输注180 min。第4组给予HEC和脂多糖输注的组合。在570分钟的研究期后，将猪处死，从脾脏中取样组织并冷冻。在每个样品的四个切片中，使用体视学方法分析B和T淋巴细胞的凋亡：通过荧光免疫组织化学用抗活性半胱天冬酶-3和抗CD 21（B淋巴细胞）或抗CD 3 γ（T淋巴细胞）估计凋亡的B和T细胞的数量。结果：内毒素血症可诱导脾脏B淋巴细胞（P < 0.001）和T淋巴细胞（P = 0.016）凋亡，且这种作用与钳夹（高胰岛素血症和正常胰岛素）无关。内毒素血症和非内毒素血症猪脾组织中B和T淋巴细胞的凋亡细胞比率分别为2.4（置信区间，1.7-3.4）和1.6（置信区间，1.1-2.2）。与内毒素输注无关，HEC增加了凋亡淋巴细胞的数量（对于B和T淋巴细胞，分别为P = 0.029和P = 0.038）。在猪处理和未处理HEC的脾细胞凋亡的数量的比率分别为1.5（置信区间，1.0-2.1）和1.5（置信区间，1.0 -2.1）为B和T lymphocyte，foresee.Conclusion：在这个猪模型中，内毒素血症和HEC增加了脾中的凋亡B和T淋巴细胞的数量。与我们的假设相反，淋巴细胞凋亡在急性内毒素血症增加了HEC。
Background: Sepsis and endotoxemia are associated with lymphocyte apoptosis. This has been regarded as harmful, contributing to further immune suppression in already immune-compromised patients. Because normalization of blood glucose improves outcome in critically ill patients, the authors hypothesized that one of the effects of insulin and normoglycemia would be inhibition of lymphocyte apoptosis. Therefore, in this experimental study in pigs, the authors examined the separate and combined effects of acute endotoxemia and a hyperinsulinemic-euglycemic clamp (HEC) on lymphocyte apoptosis.Methods: After 60 min of stabilization, 38 anesthetized and mechanically ventilated pigs (weight, 35-40 kg) were divided (by randomization performed before the experiment) into four groups and were then studied for 570 min. Group 1 received no intervention. Group 2 received a HEC (5 mm p-glucose, insulin infusion rate of 0.6 mU center dot kg(-1) center dot min(-1)) for 570 min. Group 3 received a lipopolysaccharide infusion for 180 min. Group 4 was given a combination of a HEC and a lipopolysaccharide infusion. After the 570-min study period, the pigs were killed, and tissue was sampled from the spleen and frozen. In four sections of each sample, the apoptosis of B and T lymphocytes were analyzed using stereologic methods: The number of apoptotic B and T cells was estimated by fluorescence immunohistochemistry with anti-active caspase-3 and either anti-CD21 (B lymphocytes) or anti-CD3 epsilon (T lymphocytes). The number of apoptotic B and T lymphocytes was then compared using two-way analysis of variance, and the interaction between endotoxemia and the clamp (hyperinsulinemia and euglycemia) was investigated.Results: Endotoxemia induced apoptosis of B (P < 0.001) and T lymphocytes (P = 0.016) in the spleen, and this effect was independent of the clamp. The ratios of apoptotic cells in the spleen tissue of pigs with and without endotoxemia were 2.4 (confidence interval, 1.7-3.4) and 1.6 (confidence interval, 1.1-2.2) for B and T lymphocytes, respectively. independent of endotoxin infusion, HEC increased the number of apoptotic lymphocytes (P = 0.029 and P = 0.038 for B and T lymphocytes, respectively). The ratios of the number of apoptotic spleen cells in pigs treated and not treated with HEC were 1.5 (confidence interval, 1.0-2.1) and 1.5 (confidence interval, 1.0-2.1) for B and T lymphocytes, respectively.Conclusion: In this porcine model, both endotoxemia and a HEC increased the number of apoptotic B and T lymphocytes in the spleen. Contrary to our hypothesis, lymphocyte apoptosis during acute endotoxemia was augmented by a HEC.