单核细胞趋化蛋白-1在糖尿病前期非肥胖糖尿病（NOD）小鼠的胰岛以及白细胞介素-1β作用下的人及大鼠胰岛细胞中表达。

Monocyte chemoattractant protein-1 is expressed in pancreatic islets from prediabetic NOD mice and in interleukin-1 beta-exposed human and rat islet cells.

作者信息

Chen M C, Proost P, Gysemans C, Mathieu C, Eizirik D L

机构信息

Gene Expression Unit, Diabetes Research Center, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium.

出版信息

Diabetologia. 2001 Mar;44(3):325-32. doi: 10.1007/s001250051622.

DOI:10.1007/s001250051622

PMID:11317664

Abstract

AIMS/HYPOTHESIS: Monocyte chemoattractant protein-1 (MCP-1) attracts monocytes and T lymphocytes, and could thus contribute to mononuclear cell infiltration in Type I (insulin-dependent) diabetes mellitus. Cytokines induce MCP-1 mRNA expression in pancreatic rat beta cells. To investigate this issue, we analysed the signal transduction for IL-1 beta-induced MCP-1 expression in rat beta cells and in vitro MCP-1 mRNA expression and protein release by human islets as well as in vivo islet MCP-1 mRNA expression in prediabetic non-obese diabetic mice.

METHODS

Fluorescence-activated cell sorting-purified rat beta cells were cultured for 6 h with IL-1 beta (30 U/ml) or MAPK inhibitors or both. Human islets were cultured for 6-72 h with the cytokines IL-1 beta, IFN-gamma or the inducible nitric oxide synthase (iNOS) inhibitor NG-methyl-L-arginine or both. We measured MCP-1 mRNA by RT-PCR and protein by ELISA. The MCP-1 mRNA expression in islets from male and female non-obese diabetic mice (2-12 weeks of age) was measured by real time reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

Interleukin-1 beta induced MCP-1 mRNA expression in rat beta cells, with a maximum induction after 6 h. A combination of p38 and ERK1/2 inhibitors decreased MCP-1 expression by 70%. IL-1 beta induced both MCP-1 mRNA expression and a threefold increase in medium MCP-1 protein accumulation in human islet cells. This effect was not prevented by iNOS blockers. In vivo there was an age-related increase in MCP-1 mRNA expression in islets from male and female non-obese diabetic mice, reaching a peak at 8 weeks.

CONCLUSIONS/INTERPRETATION: In rat and human islet cells MCP-1 mRNA is induced by IL-1 beta. Both ERK1/2 and p38 MAPK, but not nitric oxide, contribute to MCP-1 expression. In non-obese diabetic mice MCP-1 mRNA expression increases with age, peaking at the early phases of insulitis. The production of MCP-1 by pancreatic beta cells could contribute to the recruitment of mononuclear cells into pancreatic islets in early Type I diabetes.

摘要

目的/假设：单核细胞趋化蛋白-1（MCP-1）可吸引单核细胞和T淋巴细胞，因此可能在I型（胰岛素依赖型）糖尿病的单核细胞浸润中起作用。细胞因子可诱导大鼠胰腺β细胞中MCP-1 mRNA表达。为研究此问题，我们分析了IL-1β诱导大鼠β细胞中MCP-1表达的信号转导、人胰岛体外MCP-1 mRNA表达和蛋白质释放以及糖尿病前期非肥胖糖尿病小鼠体内胰岛MCP-1 mRNA表达。

方法

用IL-1β（30 U/ml）或丝裂原活化蛋白激酶（MAPK）抑制剂或两者共同培养经荧光激活细胞分选纯化的大鼠β细胞6小时。用人细胞因子IL-1β、干扰素-γ或诱导型一氧化氮合酶（iNOS）抑制剂N-甲基-L-精氨酸或两者共同培养人胰岛6至72小时。我们通过逆转录聚合酶链反应（RT-PCR）检测MCP-1 mRNA，通过酶联免疫吸附测定（ELISA）检测蛋白质。通过实时逆转录聚合酶链反应（RT-PCR）检测雄性和雌性非肥胖糖尿病小鼠（2至12周龄）胰岛中MCP-1 mRNA表达。

结果

白细胞介素-1β诱导大鼠β细胞中MCP-1 mRNA表达，6小时后诱导作用最强。p38和ERK1/2抑制剂联合使用可使MCP-1表达降低70%。IL-1β诱导人胰岛细胞中MCP-1 mRNA表达，并使培养基中MCP-1蛋白质积累增加三倍。iNOS阻滞剂不能阻止这种作用。在体内，雄性和雌性非肥胖糖尿病小鼠胰岛中MCP-1 mRNA表达随年龄增长而增加，在8周时达到峰值。

结论/解读：在大鼠和人胰岛细胞中，IL-1β可诱导MCP-1 mRNA表达。ERK1/2和p38丝裂原活化蛋白激酶均参与MCP-1表达，而一氧化氮不参与。在非肥胖糖尿病小鼠中，MCP-1 mRNA表达随年龄增长而增加，在胰岛炎早期达到峰值。胰腺β细胞产生MCP-1可能有助于I型糖尿病早期单核细胞向胰岛的募集。