Expression And Correlation Of HMGB2 And LEF-1 In Human Lumbar Disc Nucleus Pulposus

Objective: To detect the mRNA and protein expression of high mobility group protein B2(HMGB2),lymphoid enhancer factor-1(LEF-1)and type II collagen(Col II)in nucleus pulposus of lumbar intervertebral disc,and to explore the correlation among HMGB2,LEF-1and Col II.Methods: A total of 35 samples of nucleus pulposus of patients with lumbar disc herniation treated in our hospital from July 10,2020 to December 31,2020 were collected,of which 20 samples were taken into this study.According to the Pfirrmann grading standard,there were 2cases of II grade,8 cases of grade III,6 cases of grade IV and 4 cases of grade V.II grade and III grade were taken as mild degeneration group(n= 10),IV grade and V grade as severe degeneration group(n = 10).The mRNA expression of HMGB2,LEF-1 and Col II in nucleus pulposus of lumbar intervertebral disc in mild degeneration group and severe degeneration group was detected by real-time fluorescence quantitative PCR(q RT-PCR).The protein expression levels of HMGB2,LEF-1 and Col II in lumbar intervertebral disc nucleus pulposus in mild degeneration group and severe degeneration group were detected by western blotting(Western-bolt).The mRNA and protein expression levels of HMGB2,LEF-1 and Col II were compared between the two groups,and the correlation of mRNA expression among HMGB2,LEF-1 and Col II was analyzed by Pearson correlation analysis.Results:1.The results of PCR showed that the relative expression of HMGB2 in severe degenerative nucleus pulposus was significantly lower than that in mild degenerative nucleus pulposus,and the difference was statistically significant(1.4881 ±0.5170 in mild degenerative nucleus pulposus,0.7176 ±0.2522 in severe degenerative nucleus pulposus,P <0.05).Compared with mild degeneration nucleus pulposus tissue,the relative expression of LEF-1 in severe degeneration nucleus pulposus tissue was significantly higher,and the difference was statistically significant(0.7482 ±0.3714 in mild degeneration nucleus pulposus tissue,1.8074 ±0.6428 in severe degeneration nucleus pulposus tissue,P < 0.05).Compared with mild degeneration nucleus pulposus tissue,the relative expression of Col II in severe degeneration nucleus pulposus tissue was significantly lower,and the difference was statistically significant(mild degeneration nucleus pulposus tissue: 2.1455 ±0.5051,severe degeneration nucleus pulposus tissue: 1.3826 ±0.5781,P < 0.05).2.The results of Western-blot showed that the relative expression of HMGB2 in severe degenerative nucleus pulposus tissue was significantly lower than that in mild degenerative nucleus pulposus tissue,and the difference was statistically significant(0.6133 ±0.8737 in mild degeneration nucleus pulposus tissue and 0.1400 ±0.8888 in severe nucleus pulposus degeneration tissue,P < 0.05).Compared with mild degeneration nucleus pulposus tissue,the relative expression of LEF-1 in severe degeneration nucleus pulposus tissue was significantly higher,but the difference was not statistically significant(mild degeneration nucleus pulposus tissue: 0.1667 ±0.2108,severe degeneration nucleus pulposus tissue: 0.4233 ±0.2055,P > 0.05).Compared with mild degeneration nucleus pulposus tissue,the relative expression of Col II in severe degeneration nucleus pulposus tissue was significantly lower,but the difference was not statistically significant(mild degeneration nucleus pulposus tissue: 0.3100 ±0.1300,severe degeneration nucleus pulposus tissue: 0.1267 ±0.2082,P > 0.05).Conclusion: The expression levels of HMGB2 and LEF-1 are different in nucleus pulposus of lumbar intervertebral disc with different degrees of degeneration.The expression levels of mRNA of HMGB2,LEF-1 and Col II are correlated.HMGB2 and LEF-1 may be related to IDD,but the specific mechanism still needs to be further studied.