Study On The Role And Mechanism Of α-MSH In Brain Protection In Rats With Severe Traumatic Brain Injury

Objective: A severe traumatic brain injury(STBI)model was established in rats to observe the interleukin-6 beta(IL-6beta)and tumor necrosis factor-α)expression and the proportion of positive cells of nuclear factor-κB,TRPM2,and Casepase-9,changes in brain tissue water content,and explore the brain protective effect of α-MSH on post-STBI brain injury and its mechanism.Methods: 56 adult male SD rats of clean grade were selected as subjects of this study,Build a model by improving Feeney’s method,and were divided into 4 groups according to the random number table method.The sham operation group(sham gorup),severe traumatic brain injury group(STBI gorup),and post-cranial-injury α-MSH treatment group(α-MSH group)were selected.14 rats in the placebo group after STBI.The weight of each SD male rat ranged from 280 g to 300 g.The sham-operated group was treated by scalp incision after chloral hydrate anesthesia and drilled.In the injured group(STBI),an anesthesia was performed and a hole was punched.After cranial injury,α-MSH(1 mg/ml)was administered to the α-MSH-treated group(α-MSH group)by tail vein injection at 1 mg/kg.Treatment with 0.9%sodium chloride was performed in the placebo group(0.9% Nacl group)after severe traumatic brain injury.Six hours and 12 hours after the injury,the children were scored for behavior and scored at the end of 24 hours to determine the brain tissue at the brain injury.Wet and dry weighing methods were used to measure the inflammatory cytokines by ELISA.Interleukin-6β,tumor necrosis factor-α content,and the ratio of the number of nuclear factor-κB-positive cells decreased.Results: 1.The 6-hour and 12-hour behavioral scores of craniocerebral injury in α-MSH group were significantly lower than those in STBI group,and 0.9% Nacl group(P<0.05).The difference was statistically significant in the α-MSH group at 6 hours and 12 hours after injury.Hours of behavioral score higher;Compared with Sham group,P>0.05,the difference was not statistically significant.2.The brain tissue water content in α-MSH group after craniocerebral injury was significantly lower than that in STBI group,and 0.9% Nacl group(P<0.05).The brain tissue water content was lower in α-MSH group;Compared with Sham group,P>0.05,the difference was not statistically significant.3.The content of IL-6β and TNF-α in α-MSH group after craniocerebral injury was significantly lower than that in STBI group,and 0.9% Nacl group(P<0.05).Lower content of IL-6β and TNF-α were found in α-MSH group;Compared with Sham group,P>0.05,the difference was not statistically significant.4.After craniocerebral injury,the number of NF-κB positive cells inα-MSH group was significantly lower than that in STBI group,and 0.9% Nacl group(P<0.05).The proportion of NF-κB positive cells in α-MSH group was decreased obviously;Compared with Sham group,P>0.05,the difference was not statistically significant.5.The expression of TRPM2 positive cells in α-MSH group was significantly lower than that in STBI group,and 0.9% Nacl group after craniocerebral injury(P<0.05).The positive expression of TRPM2 was lowerin α-MSH group;Compared with Sham group,P>0.05,the difference was not statistically significant.6.The positive expression of Casepase-9 in α-MSH group after craniocerebral injury was significantly higher than that in STBI group,and0.9% Nacl group(P<0.05).The positive expression of Casepase-9 in α-MSH group was more obviously lower;Compared with Sham group,P>0.05,the difference was not statistically significant.Conclusion: 1.It is simple and convenient to use the improved Feeney’s method to establish the model,and it has good repeatability and controllability;2.Increased water content of damaged brain tissue after STBI treatment can reduce cerebral edema in rats after α-MSH treatment3.after severe traumatic brain injury treated with alpha MSH can improve the severe traumatic brain injury experimental animal ethology score,reduce interleukin-6 beta,tumor necrosis factor alpha cells,inflammatory factors such as expression,reduce nuclear factor-kappa B cell activation ratio predominate,and reduce TRPM2 positive cells expression and the positive cells expressing Casepase-9.4.The effect of α-MSH in treatment of severe craniocerebral injury is effective and can effectively protect the damaged brain tissue.