CGRP Regulates Nucleus Pulposus Cell Apoptosis and Inflammation via the MAPK/NF-κB Signaling Pathways during Intervertebral Disc Degeneration

Figure 3

CGRP repressed cell proliferation and triggered cell apoptosis in vitro. (a) CGRP changed the cell shape in a dose-dependent manner, which exhibited a long stripe, polygon, and even collapsed shape. (b) CCK 8 analysis indicated that the NP cell viability was concentration-dependently decreased by CGRP. (c) The gene transcription of PCNA in human NP cells dose-dependently decreased after treated with CGRP. (d, e) Human NP cells treated with CGRP showed higher apoptotic percentage, indicating the proapoptotic effect of CGRP on human NP cells. (f) CGRP expedited the gene transcription of C-caspase 3 and Bax and inhibited the gene transcription of Bcl-2 with the concentration above 1 μM. (g) Immunofluorescence results suggested that the protein expression of Cleaved-caspase 3 was elevated in CGRP-treated human NP cells. (h) CGRP could dose-dependently promote cell apoptosis in protein level. , , , and ; ns: no significance.  μm.

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