The Repair Mechanism Of AKBA On Sciatic Nerve Injury In Rats Based On Genomics

In recent years,with the rapid development of small animal clinical medicine,cases of peripheral nerve injury in small animals have increased year by year,and the treatment of peripheral nerve injury has become the focus of veterinarians.Therefore,the search for the development of repair drugs for the treatment of peripheral nerve damage has become an urgent need for small animals.In this test,the active component of the blood-activating and blood-stasis-reducing drug Frankincense,11-carbonyl-β-acetyl boswellic acid(AKBA),was used as a test drug to study its repairing effect on sciatic nerve injury,and to develop small New ideas and methods for the treatment of peripheral nerve injury in animals.The experiment selected 180～220 g male SD rats,randomly divided into blank group,sham operation group,model control group,AKBA medication group and methylcobalamin control group.In the blank group,the rats were not treated.In the sham operation group,the rats were surgically exposed to the sciatic nerve,but the sciatic nerve was not treated.The other three groups were surgically exposed to the sciatic nerve,and the sciatic nerve was extruded using vascular forceps to make the sciatic nerve injury model.The test was administered by intragastric administration.The blank group(normal saline),sham operation group(normal saline),model control group(normal saline),AKBA medication group(10 mg/kg),and methylcobalamin control group(1 mg/kg)were administered for 30 days.The sciatic functional index(SFI)and toe pinch tests were performed on the 10 th,20th,and 30 th days of the experiment.On the 30 th day,all rats were killed and sampled,and the repair of sciatic nerve myelin sheath was observed by transmission electron microscope.Luxol fast blue(LFB)stained myelin sheath,silver-plated stained nerve fibers,and observed the repair after injury.Immunohistochemical detection of myelin basic protein(MBP)and β3Tubulin(Tuj1).Transcriptome test was performed using second-generation gene sequencing.The original sequence was obtained using Fast QC software.Raw reads were detected by the Trim Galore method.Data were filtered,and the filtered clean reads were compared to the rat transcriptome database using HISAT2 software.Real-time quantitative polymerase chain reaction(q RTPCR)technology and Western blot(WB)technology to verify the genomics results,and then clarify the AKBA drug group rats sciatic nerve injury repair mechanism.Results: Sciatic nerve function index showed that the sciatic nerve function of the AKBA medication group and the methylcobalamin control group gradually recovered,but the model control group had poor recovery of sciatic nerve function.Toe pain test results showed that the pain response of the AKBA group and the mecobalamin control group was higher than the model control group at the10 th,20th and 30 th day.Transmission electron microscopy results showed that the number of myelin sheaths in the AKBA group and the methylcobalamin control group was significantly increased compared with the model control group,and the myelin sheaths were clear and densely arranged.The LFB staining of the sciatic nerve showed that,in the model group,a large number of myelin sheaths were dissolved,forming a large number of lipid vacuoles,and the shape of the myelin sheath was different.But compare with the model group,the rich in quantity of myelin sheaths,without lipid vacuoles of the AKBA group and the mecobalamin control group.The sciatic nerve silver-plated staining results showed that the model control group had incomplete nerve fibers,disordered axons,uneven thickness,and more separated axons at the broken ends.while the nerve fibers were intact,the thickness of the axon is uniform,in the AKBA group and methylcobalamin group.The immunohistochemical results of MBP showed that compared with the model control group,the MBP expression level of the blank control group,the sham operation group and the AKBA group increased significantly(P <0.01),while the MBP expression level of the methylcobalamin control group increased(P<0.05).The Immunohistochemical results of β3Tubulin showed that compared with the model control group,the β3Tubulin expression in the blank control group and the AKBA drug group was significantly increased(P<0.01),while the sham operation group was increased in β3Tubulin expression(P<0.05).Genomics results showed that the model control group had 189 genes up-regulated and 69 genes down-regulated compared with the AKBA group;the AKBA group had 194 genes up-regulated and 161 genes down-regulated compared with the sham operation group,and the model control group compared with the sham operation group There were 171 up-regulated genes and 239 down-regulated genes.Comparison of the differentially expressed genes in GO analysis showed that among the different groups,the AKBA group accounted for the largest proportion in the biological process(BP).KEGG pathway analysis revealed that the phagocytic pathway showed the most abundant gene expression in the AKBA and model groups.Moreover,the brain-derived neurotrophic factor(BDNF)and nerve growth factor receptor(NGFR)genes are important in the NGF signaling pathway.According to the results of genomics,q RTPCR verification of BDNF,NGFR,NGF and phagocytic pathway(MPO)related to sciatic nerve injury was performed.The results showed that compared with the model control group,the NGFR,NGF and BDNF gene expression levels of the AKBA group and the methylcobalamin group increased significantly(P<0.01).Compared with the model control group,the MPO gene expression level of the AKBA group and the methylcobalamin group was significantly reduced(P<0.01).At the same time,the protein levels of these genes were also tested,and the results showed that: compared with the model control group,the protein content of AKBA group in BDNF,NGFR,NGF increased significantly(P<0.05 or P<0.01),MPO protein content was significantly reduced(P<0.01).Conclusion: AKBA can promote the recovery of motor function and sensory function of injured sciatic nerve in rats,and promote the repair of nerve fiber and myelin injury.AKBA can increase the gene expression and protein content of BDNF,NGFR,and NGF in the neurotrophic factor pathway,and also can reduce the protein content of MPO in the signaling pathway of the phagocytic pathway and promote the repair of rat sciatic nerve injury.