Ultrashortwave Radiation Promotes The Recovery Of Spinal Cord Injury By Inhibiting Inflammation Via Suppression Of The MK2/TNF-? Pathway

Objective:Traumatic spinal cord injury?SCI? was a problematic central nervous system disease that resulted in a substantial burden on human society,and had a marked effect on the mind and body of patients.At present,the traditional treatment methods for SCI mainly included surgical anastomosis and decompression,functional rehabilitation,symptomatic drug treatment,and acupuncture.These methods mainly prevented the disease from worsening,control the secondary injury,apply enzyme preparation to inhibit and eliminate connective tissue scars,etc.However,since spinal nerve cells did not have self-repairing ability,the traditional treatment of spinal cord injury cannot produce the expected clinical effect,and it still inevitably caused paraplegia.Ultrashort wave?USW? treatment had received increasing attention in the clinic.USW had a wide range of functions,can expand local blood vessels,improved local blood circulation and tissue nutrition,but also anti-inflammatory and analgesic,improved neuromuscular excitability and biological activity.USW had been reported to have a protective effect on SCI.Inflammatory was an important part of the secondary injury of SCI.It usually lasted for a long time and has a wide range of damage.The most common inflammatory factors were TNF-? and IL-1?,which play a very important role in cytotoxicity.Mitogen-activated protein kinase?MAPK?-activated protein kinase 2?MK2? was a novel molecular target for the inflammatory response in SCI.MK2 was involved in the regulation of cell cycle,cell migration,actin remodeling,and inflammatory responses.MK2 was also involved in the inflammatory process of arthritis,hypertension,atherosclerosis,Alzheimer's disease,acute pancreatitis,and psoriasis.The present study focused on the effect of USW radiation on astrocyte inflammation.Using H2O2-treated astrocyte SCI cell models and construction of an SCI rat model,it was revealed that USW radiation inhibited the MK2-mediated inflammatory response and promoted the repair of SCI.The findings of the present study provided an improved understanding of USW radiation in the treatment of SCI.Methods:Serum samples from 20 patients with acute SCI and 20 normal serum samples without SCI were collected.The expression of MK2 was detected by Realtime PCR and Western Blot.A cell model of C8-D1A astrocytes was used to simulate the post-SCI inflammatory response using H₂O₂.The expression of TNF-?and IL-1?was detected by Realtime PCR and Western Blot.The expression of MK2 was detected by Realtime PCR,Western Blot and immunofluorescence,and the expression of MK2/TNF-?pathway in SCI was determined.USW was used to intervene in SCI cell model,and the expression of MK2,TNF-?and IL-1?was detected by Realtime PCR and Western Blot,and apoptosis was detected by TUNEL.The pcDNA3.1-MK2 overexpression plasmid was transfected,and the expression of MK2 was detected by Realtime PCR,Western Blot and immunofluorescence.The expression of TNF-?and IL-1?was detected by Realtime PCR and Western Blot.The apoptosis was detected by TUNEL.To clarify the effect of USW on SCI and the effect of USW on MK2/TNF-?pathway in vitro.USW was used to intervene in SCI rat model,Basso Beatlie Bresnahan scores was used to detect the effect of USW on functional recovery of SCI rats.Immunohistochemistry,Realtime PCR and Western Blot were used to detect the expression of MK2,TNF-?and IL-1?,and TUNEL was used to detect apoptosis.To determine the effect of USW on functional recovery,apoptosis and MK2/TNF-?pathway in SCI rats.Results:1.The mRNA and protein expression level of MK2 in serum samples from patients with SCI were higher than those in non-SCI patients?P<0.01?.2.The mRNA and protein expressions of MK2,TNF-?and IL-1?in H₂O₂-treated C8-D1A astrocytes were significantly higher than those in the control group?P<0.01?.3.In the cell model in vitro,the mRNA and protein expression levels of MK2,TNF-? and IL-1? in the H₂O₂ group and the H₂O₂+USW group were significantly increased?P<0.01?.Compared with the H₂O₂ group,the mRNA and protein expression levels of MK2,TNF-? and IL-1?in the H₂O₂+USW group were significantly decreased?P<0.05?.Compared with the control group,the apoptosis level of H₂O₂ group and H2O2+USW group was significantly increased?P<0.01?.Compared with the H₂O₂ group,the apoptosis level of the H₂O₂+USW group was significantly decreased?P<0.01?.4.After overexpression of MK2,it was found that the mRNA and protein expression levels of MK2,TNF-?and IL-1?in H₂O₂+USW+pcDNA3.1 group were significantly lower than those in H₂O₂+pcDNA3.1 group,and compared with H₂O₂+USW+pcDNA3.1 group,the expression of MK2,TNF-?and IL-1?in H₂O₂+USW+pcDNA3.1-MK2 group was significantly increased?P<0.01?.Compared with H₂O₂+pcDNA3.1 group,the apoptosis level of H₂O₂+USW+pcDNA3.1 group was significantly decreased?P<0.01?.Compared with the H₂O₂+USW+pcDNA3.1 group,the apoptosis level of H₂O₂+USW+pcDNA3.1-MK2 group was significantly increased?P<0.01?.5.In the animal model in vivo,the BBB score of the USW group was significantly higher than that of the control group?SCI rats?,and the expression of MK2,TNF-?and IL-1?in the USW group was significantly lower than that of the control group?P<0.01?,the number of apoptotic cells was also significantly reduced?P<0.01?.Conclusion:1.In this study,it was confirmed that the inflammatory response is an important process in the process of spinal cord injury in vitro and in vivo animal experiments,and USW could promote the functional recovery of SCI.2.After SCI,MK2/TNF-?pathway was activated,MK2,TNF-?and IL-1?were increased,which could aggravate the inflammatory response and lead to further damage of the spinal cord.3.USW could inhibit the expression of MK2,TNF-?and IL-1?,inhibit the inflammatory response,and promotes the recovery of spinal cord function by inhibiting the MK2/TNF-?pathway after SCI.4.USW could also prevent further damage of SCI by inhibiting apoptosis,and promote the recovery of neurological function of SCI.