Caspase-1 inhibitor Ac-YVAD-CHO attenuates quinolinic acid-induced increases in p53 and apoptosis in rat striatum

Aim: To study the effects of the Caspase-1 inhibitor Ac-YVAD-CHO on quinolinic acid (QA)-induced Apoptosis.

Methods: Rats were pre-treated with intrastriatal infusion of Ac-YVAD-CHO (2-8 microg) before intrastriatal injection of QA (60 nmol). Striatal total proteins, genomic DNA, and nuclear proteins were isolated. The effects of Ac-YVAD-CHO on QA-induced Caspase-1 activity, internucleosomal DNA fragmentation, IkappaB-alpha degradation, NF-kappaB, and AP-1 activation, and increases in p53 protein levels were measured with Enzyme assays, Agarose gel electrophoresis, electrophoresis mobility shift assays, and Western blot analysis.

Results: Pre-treatment with Ac-YVAD-CHO inhibited QA-induced internucleosomal DNA fragmentation. Ac-YVAD-CHO inhibited QA-induced increases in Caspase-1 activity and p53 protein levels, but had no effect on QA-induced IkappaB-alpha degradation, NF-kappaB or AP-1 activation.

Conclusion: Caspase-1 is involved in QA-induced p53 upregulation but not IkappaB-alpha degradation. Inhibition of Caspase-1 attenuates QA-induced Apoptosis in rat striatum.