Objective: To investigate the inhibition effects of par-4 antisense oligodeoxynucleotide on apoptosis of PC12 cell induced by glutamate and its signal transduction mechanism.
Methods: (1) Cationic lipid-mediated par-4 antisense oligodeoxynucleotide (Par-4-AS-ODN) was transfected into PC12 cells before they were treated with glutamate. Mismatch oligodeoxynucleotide (MS-ODN) were also transfected into cells as controls. (2) Morphological observation and the detection of anti-apoptosis effects of par-4-AS-ODN on PC12 cells were done with the Laser Scanning confocal Microscope by double staining the cells with acridine orange/ethidium bromide (AO/EB), addition to with flow cytometry. (3) Western blot was used to detect the protein levels of par-4 and phosphorylated ERK(1/2) at threonine-202 and Tyrosine-204.
Results: (1) Par-4-AS-ODN significantly suppressed up-regulation of the par-4 protein levels induced by glutamate in PC12 cells. (2) Par-4-AS-ODN could resist the decrease of phosphorylated ERK(1/2) (Thr202/Tyr204) induced by glutamate in PC12 cells. (3) Par-4 AS-ODN could inhibit apoptosis of PC12 cells induced by glutamate. But its inhibition effect could be eliminated by PD98059, a selective MEK(1) inhibitor which could inhibit phosphorylation of ERK(1/2).
Conclusion: Par-4 AS-ODN may inhibit apoptosis of PC12 cells induced by glutamate, and its inhibition effects may be medicated by the activation of ERK(1/2).