Journal of Molecular Neuroscience

, Volume 50, Issue 1, pp 98–108 | Cite as

Neuroprotective Effect of Protease-Activated Receptor-2 in the Hypoxia-Induced Apoptosis of Rat RGC-5 Cells



Hypoxia-induced apoptosis of retinal ganglion cells (RGCs) is regarded as a pivotal pathological process in various ocular diseases. Protease-activated receptor-2 (PAR-2) is involved in the regulation of cell inflammation, differentiation, and apoptosis in many cell types and tissues, but the role of PAR-2 in RGCs under pathological conditions remains unknown. The purpose of this study was to investigate the role of PAR-2 in the apoptosis of RGCs under hypoxic stress. An immortalized rat RGC line (RGC-5) was exposed to hypoxia (5 % O2). The expression and location of PAR-2 in RGC-5 cells under hypoxia stress were investigated using real-time PCR, western blotting and immunocytochemistry. Cell viability was determined using the Cell Counting Kit-8 assay. Apoptosis was detected using Hoechst 33342 staining and AnnexinV-FITC/PI assays. The role of Bcl-2, Bax, and the active subunit of caspase-3 was also investigated. The results showed that PAR-2 was functionally expressed in RGC-5 cells and up-regulated at both mRNA and protein levels under hypoxic stress. The PAR-2 selective agonist, SLIGRL, rescued RGC-5 cells from hypoxia-induced apoptosis through up-regulation of the Bcl-2/Bax ratio and down-regulation of caspase-3 activation. This study provides the first evidence that PAR-2 has a protective effect against the hypoxia-induced apoptosis of RGC-5 cells.


Protease-activated receptor-2 RGC-5 cells Hypoxia Apoptosis Caspase-3 Bcl-2/Bax ratio 


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Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Southwest Hospital, Southwest Eye HospitalThird Military Medical UniversityChongqingChina
  2. 2.Key Lab of Visual Damage and Regeneration & Restoration of ChongqingChongqingChina
  3. 3.The second affiliated Hospital of Chongqing Medical UniversityChongqingChina
  4. 4.State Key Laboratory of Trauma, Burns and Combined Injury, Institute of Burns, Southwest Hospital, Third Military Medical UniversityChongqingChina

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