Neuroprotective effects of electro-acupuncture in spinal cord injury rats via up-regulation of DUSP14

Abstract

Purpose: To study the effect and mechanism of action of electro-acupuncture (EA) on nerve regeneration by analyzing the behavior, inflammation and cell death in spinal cord injury (SCI) rat model.
 Methods: SCI model was established according to Allen’s falling strike method. Electroacupuncture was performed on Jiaji (EX-B2)/Mingmen (GV4) acupoint with a 1 mA current intermittent wave at a frequency of 2Hz for 20 min daily. Interleukin (IL-6) and tumor necrosis factor-α (TNF-α) levels were measured using ELISA kits. Apoptosis-induced DNA strand breaks were evaluated by TUNEL assay while relative mRNA expression was assessed by quantitative real-time polymerase chain reaction (qRT-PCR). Protein levels were measured by western blot.
 Results: Relative mRNA and protein expressions of DUSP14 decreased in SCI rats with time but increased by EA treatment. Further, partial locomotor functional recovery was presented in SCI rats by EA treatment. Moreover, intraspinal injection of DUSP14 over-expression viral supernatants/EA treatment ameliorated inflammation and apoptosis in SCI rats. Meanwhile, the protein levels of NF-κB p65 (nucleus) and phosphorylated TGF-activated kinase 1 (p-TAK1) increased in SCI rats following EA treatment but were decreased by EA treatment and intraspinal injection of DUSP14 over-expression viral supernatants.
 Conclusion: EA acupoint treatment exerts neuroprotective effects in SCI rats via the reduction of inflammation and apoptosis, and induction of DUSP14.

Oxidative DNA Damage in the Pathophysiology of Spinal Cord Injury: Seems Obvious, but Where Is the Evidence?

“…DNA gel electrophoresis and TUNEL assays have been performed on SCI tissue since 1999 and are still being performed to date. With such techniques, it has been repeatedly found that DNA fragmentation occurs in the spinal cord following injury at 1 to 7 dpi [ 17 , 23 , 26 , 48 , 56 , 61 , 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 ]. Though one cannot distinguish in these experiments between strand breaks in viable cells that can be resolved by DNA repair and DNA fragmentation as a consequence of apoptosis, the data add to the evidence of strand breaks occurring post-SCI.…”