Effect of Zhuangyao Tongluo Formula（壮腰通络方） Containing Serum on TNF-α-mediated Vicious Circle of Pyroptosis of Nucleus Pulposus Cells / 中医杂志

ABSTRACT

ObjectiveTo explore the mechanism of Zhuangyao Tongluo Formula（壮腰通络方，ZTF） in delaying intervertebral disc degeneration. MethodsM1 macrophages were induced from THP-1 cells using LPS， IFN-γ and PMA. The induced M1 macrophages were then co-cultured with nucleus pulposus cells in a transwell system. Fetal bovine serum was used as the control serum， and the effects of different concentrations （5%， 10%， 15%， 20%） of serum from rats treated with ZTF on the activity of M1 macrophages and nucleus pulposus cells were analyzed using MTT assay. Experiment 1 was established， including the nucleus pulposus cell control group， M1 macrophage control group， nucleus pulposus cell + ZTF group， nucleus pulposus cell + TNF control group， nucleus pulposus cell + TNF + ZTF group， co-culture group， and co-culture + ZTF group. The levels of IL-1β， and IL-18 in the culture supernatant were detected using ELISA. The mRNA expression of IL-1β and IL-18 in nucleus pulposus cells was detected using qPCR. Additionally， the expression of GSDMD protein in nucleus pulposus cells was detected using cell immunofluorescence. In experiment 2， co-culture groups were constructed using TNF-α overexpression （OE） or empty vector （EV） plasmids， including co-culture group， TNF-EV + co-culture group， TNF-EV co-culture group + ZTF， co-culture + ZTF group， TNF-OE co-culture group + ZTF， and TNF-OE + co-culture group. The mRNA and protein expression of TNF-α in M1 cells in each group were detected using qPCR and WB. ResultsThe ZTF with 10% serum was selected for subsequent experiments. The results of experiment 1 showed that compared to the control group of nucleus pulposus cells， there was no statistically significant difference in the levels of IL-1β， IL-18， mRNA， and GSDMD expression in the nucleus pulposus cells + ZTF group （P＞0.05）. However， the TNF-α + co-culture group showed a significant increase in IL-1β， IL-18 levels， mRNA， and GSDMD expression （P＜0.01）. When compared to the co-culture group， the ZTF+ co-culture group showed a significant decrease in IL-1β， IL-18 levels， mRNA， and GSDMD expression （P＜0.01）. The results of experiment 2 showed that there was no statistically significant difference in TNF-α mRNA and protein expression between the empty vector plasmids + co-culture group and the co-culture group （P＞0.05）. Compared to the empty vector + co-culture group， the expression of TNF-α mRNA and protein was significantly reduced in the empty vector co-culture + ZTF group （P＜0.01）. Compared to the co-culture group and the empty vector + co-culture group， the expression of TNF-α mRNA and protein was significantly reduced in the co-culture + ZTF group （P＜0.01）. Compared to the co-culture + ZTF group， the expression of TNF-α mRNA and protein significantly increased in the overexpression vector co-culture + ZTF group （P＜0.01）. Compared to the overexpression vector co-culture + ZTF group， the expression of TNF-α mRNA and protein significantly increased in the overexpression vector co-culture group （P＜0.01）. ConclusionZTF serum can inhibit the TNF-α-induced apoptosis of nucleus pulposus cells and delay lumbar disc degeneration by reducing the expression of TNF-α in M1 macrophages.