Effect of Fas and Bcl-2 DNA Damages Response Expression in Stem Cells on Apoptosis of Nucleus Pulposus of Intervertebral Disc

Abstract

The nucleus pulposus is an elastic jelly composed of crisscross fibrous reticular structures, namely, chondrocytes and proteoglycan mucoid matrix. Embryo and adult SC can resist the accumulation of genetic damage and repair them through various DNA repair mechanisms, thus preventing them from spreading to daughter cells. Fresh medullary tissue was fixed with 10% formaldehyde solution, embedded in paraffin, and sectioned at 4 m. The nucleus pulposus was stained with HE, and its degeneration was observed under light microscope. The average apoptotic index (AI) of 20 denatured nuclei was 50.230, the percentage of Fas-positive cells was 74.255%, and the percentage of Bcl-2-positive cells was 55.370%. The average apoptotic index (AI) was 28.317. The percentage of Fas-positive cells, Fas protein-positive cells, and Bcl-2 protein-positive cells in six normal nuclei was 41.717%, 41.717%, and 27.167%, respectively. The average AI value, Fas protein expression, and Bcl-2 protein expression in the two groups were significantly different ( $P<0.05$ ).