SIRT1 attenuates neuropathic pain by epigenetic regulation of mGluR1/5 expressions in type 2 diabetic rats

In this study, we found that spinal SIRT1 expression and activity were downregulated significantly in high-fat-fed/low-dose streptozotocin-induced neuropathic pain rats. SIRT1 localized in spinal neurons but not in astrocytes or microglia. Furthermore, the expressions of metabotropic glutamate receptor (mGluR1) and mGluR5, which play a key role in central sensitization and neuropathic pain, and H3 acetylation levels at Grm1/5 (encoding mGluR1/5) promoter regions were increased in diabetic neuropathic pain rats. SIRT1 activator SRT1720 reversed thermal hyperalgesia and mechanical allodynia and spinal neuronal activation in diabetic neuropathic pain rats. Concurrently, increased expressions of mGluR1/5 and H3 acetylation levels at Grm1/5 promoter regions were reversed by SIRT1 activation. In addition, knockdown of SIRT1 by Ad-SIRT1-shRNA induced pain behaviors and spinal neuronal activation in normal rats, which was accompanied by the increased expressions of mGluR1/5 and H3 acetylation levels at Grm1/5 promoter regions. Therefore, we concluded that SIRT1-mediated epigenetic regulation of mGluR1/5 expressions was involved in the development of neuropathic pain in type 2 diabetic rats.
Source: Pain - Category: Anesthesiology Tags: Research Paper Source Type: research