Mechanism of Impaired Nerve Regeneration in Experimental Diabetic Rats

实验性糖尿病大鼠神经再生受损的机制

• 批准号: 08670703
• 负责人: TERADA Masahiko
• 金额: $ 0.9万
• 依托单位: Shiga University of Medical Science
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08670703/
• 关键词: Diabetic neuropathy; Nerve regeneration; Wallerian degeneration; Phosphorylation; Neurofilament; Cdk5; JNK; ERK; アポトーシス; 後根神経節; 坐骨神経; p35; 末梢神経; P35; ERK2; GSK3B; 免疫組織化学; ウエスタンブロット; 糖尿病; ストレプトゾシン; ラット; 形態計測; ウエスタンブッロティング

To clarify the ability of diabetic nerves to regenerate in diabetic neuropathy, we evaluated nerve regeneration after nerve crush and degeneration after nerve transection in diabetic (DM) and age-matched control rats. In nerve crush model, electrophysical examination indicated that the elongation rate of regenerative nerves and their velocity was slower in DM.Morphologically, the number of regenerative nerve was significantly decreased and its diameter was smaller in DM.In nerve transection model, morphometric analysis indicated that WD was delayed in DM.Immunoblot analysis showed a delay in the degradation of neurofilaments (NFs) in DM during WD.Moreover, phosphorylated NFs detected by SMI31 were more recognized in intact diabetic nerves in comparison with control, while the opposite was true for unphosphorylated NFs detected by SMI32.These results suggest that nerve regeneration is impaired in DM.This impairment, in part, might be due to delay of WD, because WD is prerequisite for nerve regeneration. Since it is known that the sensitivity of NF to calpain-mediated proteolysis is modulated by its carboxyl-terminal phosphorylation state and phosphorylated NFs are resistant to calpains, we concluded that abnormal NF phosphorylation state in diabetes could be one of the mechanisms by which axonal degeneration was delayed.The excessive NF phosphorylation in STZ-diabetic rats could be due to an increase in kinase activity. Proline-directed protein kinases, such as Cdk5/p35, GSK3 beta JNK, ERK, and p38, are potential candidates for NF kinases. We confirmed the existence of Cdk5/p35, JNK, and ERK using immunoblot and immunohistochemistry. Moreover, both JNK and ERK were activated in DRG and sciatic nerve of 12 weeks STZ-diabetic rats. These results suggest that JNK and ERK make an important role in hyperphosphorylation of NF in diabetic rats.

为了阐明糖尿病神经在糖尿病神经病中再生的能力，我们评估了神经减伤和神经横向变性后糖尿病（DM）和年龄匹配的对照大鼠的神经再生。在神经镇压模型中，电物理检查表明，再生神经的伸长速率及其速度在dm上较慢，再生神经的数量显着降低，其直径在DM.INEVER TRANSECTION模型中较小，形态分析表明，WD在DM.Immunobot Blabot分析中延迟了延迟的延迟。 (NFs) in DM during WD.Moreover, phosphorylated NFs detected by SMI31 were more recognized in intact diabetic nerves in comparison with control, while the opposite was true for unphosphorylated NFs detected by SMI32.These results suggest that nerve regeneration is impaired in DM.This impairment, in part, might be due to delay of WD, because WD is prerequisite for nerve再生。由于众所周知，NF对钙蛋白酶介导的蛋白水解的敏感性是由其羧基末端磷酸化状态和磷酸化的NF对钙蛋白酶具有抵抗力的调节，因此我们得出结论，糖尿病中异常NF磷酸化状态可能是轴突的机制之一。由于激酶活性的增加。脯氨酸指导的蛋白激酶，例如CDK5/P35，GSK3 Beta JNK，ERK和P38是NF激酶的潜在候选者。我们使用免疫印迹和免疫组织化学证实了CDK5/p35，JNK和ERK的存在。此外，JNK和ERK均在DRG中激活，坐骨神经为12周糖尿病大鼠。这些结果表明，JNK和ERK在NF在糖尿病大鼠中的热磷酸化中发挥了重要作用。

项目成果

Kawai H: "Axonal contact regulates expression of α2 and β2 isoforms of Na^+, K^+-ATPase in Schwann Cells : adhesion molecules and nerve regeneration." J Neurochem. 69. 330-339 (1997)

Kawai H：“轴突接触调节雪旺细胞中 Na^+、K^+-ATP 酶的 α2 和 β2 亚型的表达：粘附分子和神经再生。”J Neurochem 69. 330-339 (1997)

Terada M: "Delayed Wallerian degeneration and increased neurofilament phosphorylation in rat sciatic nerve of streptozocin-induced diabetes." J Neurol Sci. 155. 23-30 (1998)

Terada M：“链佐星诱导的糖尿病大鼠坐骨神经延迟华勒变性和神经丝磷酸化增加。”

Terada M,Yasuda H,Kikkawa R: "Delayed Wallerian degeneration and increased neurofilament phosphorylation in rat sciatic nerve of streptozocin-induced diabetes." J Neurol Sci. 155. 23-30 (1998)

Terada M、Yasuda H、Kikkawa R：“链佐星诱导的糖尿病大鼠坐骨神经延迟华勒变性和神经丝磷酸化增加。”

Terada M,Yasuda H,Kikkawa R,Shigeta Y: "Tolrestat improves nerve regeneration after crush injury in streptozocin-induced diabetic rets." Metabolism. 45 (10). 1189-1195 (1996)

Terada M、Yasuda H、Kikkawa R、Shigeta Y：“托雷司他可改善链脲佐菌素诱导的糖尿病视网膜挤压损伤后的神经再生。”

Kawai H,Yasuda H,Terada M,Omatsu-Kanbe M,Kikkawa R: "Axonal contact regulates expression of alpha2 and beta2 isoforms of Na^+, K^+-ATPase in Schwann cells : adhesion molecules and nerve regeneration." J Neurochem. 69. 330-339 (1997)

Kawai H、Yasuda H、Terada M、Omatsu-Kanbe M、Kikkawa R：“轴突接触调节雪旺细胞中 Na+、K+-ATP 酶的 α2 和 β2 亚型的表达：粘附分子和神经再生。”