Ascorbic Acid Attenuates Multifidus Muscles Injury And Atrophy After Posterior Lunbar Spine Surgery By Suppressing Inflammation,and Oxidative Stress In A Rat Model

Summary of Background Data.Previous studies show oxidative stress and inflammation are two main molecular mechanisms in multifidus muscle injury and atrophy after posterior lumbar surgery.AA may have a protective effect in postoperative multifidus muscles.Methods.Rats were divided into sham surgery,control surgery,and surgery plus AA groups.Multifidus muscles of the control and AA groups were excised from the osseous structures.The muscles were retracted continuously for 2 hours.In the sham and AA groups,AA was administered via oral gavage daily in the first week.In each group,the oxidative stress was evaluated by measuring malondialdehyde(MDA)and Total superoxide dismutase(T-SOD).The inflammation,fat degeneration,or fibrosis of multifidus muscle were evaluated by quantitative realtime polymerase chain reaction(q-PCR),histology,or immunohistochemical analysis.Results.T-SOD activity was significantly lower in the control group than that in theAA group in the first week.MDA levels were significantly higher in the AA group.Interleukin-6 and tumor necrosis factor-a in multifidus muscles also showed significant differences when treated with AA.The inflammation score on histology was significantly lower in the AA group postoperatively in the first week.In the long run,marker genes for fibrosis and fat degeneration,and fibrosis and fat degeneration scores,were significantly lower in the AA than the control group on days 14 and 28 postoperatively.Conclusion.In conclusion,AA attenuated the oxidative stress and inflammation response in the postoperative multifidus muscles,and remarkable differences were observed from the histological assessment and related marker genes expression.Our results provided important insight into the anti-inflammatory and antioxidative effects of AA in the postoperative multifidus muscles.