Stable expression of manganese superoxide dismutase (MnSOD) in insulinoma cells prevents IL-1β-induced cytotoxicity and reduces nitric oxide production
Stable expression of manganese superoxide dismutase (MnSOD) in insulinoma cells prevents IL-1β-induced cytotoxicity and reduces nitric oxide production
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DOI：
10.1172/jci1489
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发表时间：
1998-05-01
影响因子：
15.9
通讯作者：
Newgard, CB
中科院分区：
文献类型：
--
作者：
Hohmeier, HE;Thigpen, A;Newgard, CB
产生胰岛素的胰岛β细胞易受炎症细胞因子的细胞毒性作用影响，这一事实代表了使用这些细胞进行胰岛素依赖型糖尿病（IDDM）移植治疗的潜在障碍。在目前的研究中，我们发现IL-1 β诱导了INS-1胰岛素瘤细胞的破坏，而对第二种胰岛素瘤细胞系RIN1046-38及其工程衍生物没有影响，这种差异与在后一种细胞中锰超氧化物歧化酶（MnSOD）的高水平表达有关。INS-1细胞中MnSOD的稳定过表达提供了对IL-1 β介导的细胞毒性的完全保护，并且当这些细胞暴露于激活的人或大鼠PBMC的条件培养基中时，也显著减少了杀伤。此外，在RIN-或ins -1衍生的细胞系中，MnSOD的过表达导致IL-1 β诱导的一氧化氮（NO）产生急剧减少，这一发现与诱导型一氧化氮合酶（iNOS）水平降低有关。用iNOS抑制剂L-NMMA处理INS-1细胞，对lps激活的大鼠PBMC的IL-1 β或上清液提供与MnSOD过表达相同程度的保护，支持MnSOD通过干扰正常IL-1 β介导的iNOS增加来保护INS-1细胞的观点。由于NO及其衍生物已被认为是IDDM中β细胞破坏的关键介质，因此我们得出结论，对MnSOD过表达进行工程化的调节良好的胰岛素瘤细胞系可能是自身免疫性糖尿病中孤立胰岛作为胰岛素替代载体的一个有吸引力的选择。
The fact that insulin-producing islet beta-cells are susceptible to the cytotoxic effects of inflammatory cytokines represents a potential hinderance to the use of such cells for transplantation therapy of insulin-dependent diabetes mellitus (IDDM). In the current study, we show that IL-1 beta induces destruction of INS-1 insulinoma cells, while having no effect on a second insulinoma cell line RIN1046-38 and its engineered derivatives, and that this difference is correlated with a higher level of expression of manganese superoxide dismutase (MnSOD) in the latter cells. Stable overexpression of MnSOD in INS-1 cells provides complete protection against IL-1 beta-mediated cytotoxicity, and also results in markedly reduced killing when such cells are exposed to conditioned media from activated human or rat PBMC. Further, overexpression of MnSOD in either RIN- or INS-1-derived lines results in a sharp reduction in IL-1 beta-induced nitric oxide (NO) production, a finding that correlates with reduced levels of the inducible form of nitric oxide synthase (iNOS). Treatment of INS-1 cells with L-NMMA, an inhibitor of iNOS, provides the same degree of protection against IL-1 beta or supernatants from LPS-activated rat PBMC as MnSOD overexpression, supporting the idea that MnSOD protects INS-1 cells by interfering with the normal IL-1 beta-mediated increase in iNOS. Because NO and its derivatives have been implicated as critical mediators of beta-cell destruction in IDDM, we conclude that well regulated insulinoma cell lines engineered for MnSOD overexpression may be an attractive alternative to isolated islets as vehicles for insulin replacement in autoimmune diabetes.