米诺环素对糖尿病大鼠脊髓小胶质细胞极化的影响

The effects of minocycline on microglial cell polarization in spinal cord of diabetic rats

目的:研究米诺环素对糖尿病大鼠脊髓小胶质细胞极化的影响。方法:27只成年雄性SD大鼠分为对照组(control)、糖尿病组(DM)、米诺环素处理组(minocyline),利用腹腔注射链脲菌素(STZ)方法制备糖尿病大鼠模型,检测大鼠的血糖及体重变化,免疫荧光染色检测大鼠脊髓Iba-1的表达,酶联免疫吸附试验(ELISA)检测大鼠脊髓肿瘤坏死因子α(TNF-α)、白细胞介素6(IL-6)、转化生长因子β(TGF-β)和白细胞介素10(IL-10)的水平变化,Western Blot检测大鼠脊髓CD68、精氨酸酶-1(Arg-1)、髓鞘相关糖蛋白(MAG)和髓鞘碱性蛋白(MBP)的表达变化。结果:STZ注射成功制备了糖尿病大鼠模型;免疫组化染色显示糖尿病模型大鼠脊髓Iba-1阳性细胞增多;ELISA检测结果显示糖尿病组大鼠脊髓组织中M1型小胶质细胞特异性细胞因子(TNF-α和IL-6)水平增加,米诺环素处理组大鼠脊髓组织中M2型小胶质细胞特异性细胞因子(TGF-β和IL-10)水平增加;Western Blot结果显示STZ组大鼠脊髓CD68表达上调,MAG和MBP表达降低,而米诺环素治疗组Arg-1、MAG和MBP表达均增加。结论:糖尿病大鼠脊髓小胶质细胞被激活,米诺环素处理可促使小胶质细胞向M2表型转化并促进髓鞘再生。

Objective:To study the effects of minocycline on microglia polarization in diabetic rats.Methods:Twenty seven adult male SD rats were divided into control group(control)group,diabetes mellitus(DM),minocycline treatment group(minocyline).DM model was prepared by intraperitoneal injection of streptozotocin(STZ).Blood glucose and weight change of rats were detected.The expression of spinal Iba-1 was detected by immunohistochemistry staining.To detect the rat spinal cord The levels of tumor necrosis factorα(TNF-α),interleukin 6(IL-6),IL-10,and transforming growth factor β(TGF-β)were detected by enzyme-linked immunosorbent assay(ELISA).The expressions of CD68,arginase-1(Arg-1),myelin associated glycoprotein(MAG),and myelin basic protein(MBP)were detected by Western Blot.Results:Rat DM model was prepared successfully by STZ injection.The number Iba-1 positive cells increased in the spinal cord of DM rats.M1 microglia-associated cytokines(TNF-α and IL-6)increased in the DM group rats,while M2-microglia-associated cytokines(TGF-β and IL-10)increased in the minocycline group rats.The expression of CD68 was up-regulated,while the expression of MAG and MBP was down-regulated in DM group rats.The expressions of Arg-1,MAG,and MBP were up-regulated in minocycline group rats.Conclusion:Microglia was activated in spinal cord of DM rats.Minocycline treatment can promote microglia to transform into M2 phenotype and myelin regeneration.