Ruihua Zhang1, Dan-Ning Hu1,2, Richard Rosen1,2. 1. Eye and Vision Research Institute, Department of Ophthalmology, Icahn School of Medicine at Mount Sinai, New York 10029, USA. 2. Department of Ophthalmology, New York Eye and Ear Infirmary of Mount Sinai, New York 10003, USA.
Abstract
AIM: To test our hypothesis that activation of protein kinase A (PKA) signal pathway by β-adrenergic agonist plays an important role in the protecting of cultured retinal pigment epithelial (RPE) cells against the hydroxychloroquine (HCQ) toxicity. METHODS: Cultured human RPE cells were treated with 1) HCQ, 2) HCQ with salbutamol (a β2-adrenergic receptor agonist), and 3) HCQ with salbutamol and a PKA inhibitor, and compared these to 4) untreated cells (controls). After treated for 24h, cell vacuolation, cells viability, PKA and PKA kinase activity levels were determined by the measurement of the size of vacuoles using Image J software, the cell counting with a dye-exclusion testing, Western blot and PKA kinase detection, respectively. RESULTS: Cell vacuolation and cell death of cultured RPE cells were significantly increased by the treatment of HCQ. Salbutamol significantly elevated PKA and PKA activity levels and this was associated with the inhibition of the vacuolation and cell death. The PKA inhibitor significantly decreased the PKA levels and eliminated the protective effects of salbutamol on HCQ-treated RPE cells. CONCLUSION: The PKA pathway plays an important role in the protective effects of β2-adrenergic agonist on the RPE cells against HCQ toxicity. These findings reveal a novel potential strategy against HCQ retinopathy by treatment with PKA activating medications. International Journal of Ophthalmology Press.
AIM: To test our hypothesis that activation of protein kinase A (PKA) signal pathway by β-adrenergic agonist plays an important role in the protecting of cultured retinal pigment epithelial (RPE) cells against the hydroxychloroquine (HCQ) toxicity. METHODS: Cultured human RPE cells were treated with 1) HCQ, 2) HCQ with salbutamol (a β2-adrenergic receptor agonist), and 3) HCQ with salbutamol and a PKA inhibitor, and compared these to 4) untreated cells (controls). After treated for 24h, cell vacuolation, cells viability, PKA and PKA kinase activity levels were determined by the measurement of the size of vacuoles using Image J software, the cell counting with a dye-exclusion testing, Western blot and PKA kinase detection, respectively. RESULTS: Cell vacuolation and cell death of cultured RPE cells were significantly increased by the treatment of HCQ. Salbutamol significantly elevated PKA and PKA activity levels and this was associated with the inhibition of the vacuolation and cell death. The PKA inhibitor significantly decreased the PKA levels and eliminated the protective effects of salbutamol on HCQ-treated RPE cells. CONCLUSION: The PKA pathway plays an important role in the protective effects of β2-adrenergic agonist on the RPE cells against HCQtoxicity. These findings reveal a novel potential strategy against HCQretinopathy by treatment with PKA activating medications. International Journal of Ophthalmology Press.
Authors: Sonia Guha; Gabriel C Baltazar; Leigh-Anne Tu; Ji Liu; Jason C Lim; Wennan Lu; Arthur Argall; Kathleen Boesze-Battaglia; Alan M Laties; Claire H Mitchell Journal: J Neurochem Date: 2012-06-27 Impact factor: 5.372
Authors: Ji Liu; Wennan Lu; Sonia Guha; Gabriel C Baltazar; Erin E Coffey; Alan M Laties; Ronald C Rubenstein; William W Reenstra; Claire H Mitchell Journal: Am J Physiol Cell Physiol Date: 2012-05-09 Impact factor: 4.249