AIM: To study the contribution of tonicity response element binding protein(Ton EBP) in retinal ganglion cell(RGC) death of diabetic retinopathy(DR).METHODS: Diabetes was induced in C57BL/6 mice by five consecutive in...AIM: To study the contribution of tonicity response element binding protein(Ton EBP) in retinal ganglion cell(RGC) death of diabetic retinopathy(DR).METHODS: Diabetes was induced in C57BL/6 mice by five consecutive intraperitoneal injections of 55 mg/kg streptozotocin(STZ). Control mice received vehicle(phosphate-buffered saline). All mice were killed 2mo after injections, and the extent of cell death and the protein expression levels of Ton EBP and aldose reductase(AR) were examined.RESULTS: The Ton EBP and AR protein levels and the death of RGC were significantly increased in the retinas of diabetic mice compared with controls 2mo after the induction of diabetes. Terminal deoxynucleotidyl transferase(Td T)-mediated d UTP nick end labeling(TUNEL)-positive signals co-localized with Ton EBP immunoreactive RGC. These changes were increased in the diabetic retinas compared with controls.CONCLUSION: The present data show that AR and Ton EBP are upregulated in the DR and Ton EBP may contribute to apoptosis of RGC in the DR.展开更多
AIM:To investigate the retinal toxicity and pharmacokinetics of simvastatin intravitreally injected into mice.METHODS:Forty-eight 6-8-week-old C57BL/6J mice were used in this study.Simvastatin was intravitreally inj...AIM:To investigate the retinal toxicity and pharmacokinetics of simvastatin intravitreally injected into mice.METHODS:Forty-eight 6-8-week-old C57BL/6J mice were used in this study.Simvastatin was intravitreally injected into the right eye of each mouse;the left eye was injected with vehicle and was used as a control.Bilateral dark-adapted electroretinography(ERG)was performed 1 and 7d following injection.Histology was examined using a combination of light,fluorescence and electron microscopy.Highperformance liquid chromatography(HPLC)was used to determine the decay in the retinal simvastatin concentration.RESULTS:ERG revealed no significant changes in the simvastatin-injected eyes compared to control.Histologic studies showed normal retinal morphology in eyes injected with simvastatin up to a final vitreal concentration of 200μmol/L.No significant changes in the number of photoreceptors,bipolar cells or ganglion cells were found.The retinal simvastatin concentration decayed exponentially,with a half-life of 1.92-2.41h.CONCLUSION:Intravitreal injection of up to 200μmol/L simvastatin produced no signs of adverse effects in the mouse retina.Simvastatin reaches the retina shortly after intravitreal injectionand has a short half-life.展开更多
基金Supported by the Basic Research Program of the Korea Science & Engineering Foundation (No. 2009-0068732)the Basic Research Program of the National Research Foundation of Korea (No.2011-0020163)+1 种基金the Bio-Industry Technology Development Program funded by the Korea Institute of Planning & Evaluation for Technology in Food, Agriculture Forestry & Fisheries (No.112005-3)the BK21 Program and by the MRC program of KRF (R13-2005-012-01001-1)
文摘AIM: To study the contribution of tonicity response element binding protein(Ton EBP) in retinal ganglion cell(RGC) death of diabetic retinopathy(DR).METHODS: Diabetes was induced in C57BL/6 mice by five consecutive intraperitoneal injections of 55 mg/kg streptozotocin(STZ). Control mice received vehicle(phosphate-buffered saline). All mice were killed 2mo after injections, and the extent of cell death and the protein expression levels of Ton EBP and aldose reductase(AR) were examined.RESULTS: The Ton EBP and AR protein levels and the death of RGC were significantly increased in the retinas of diabetic mice compared with controls 2mo after the induction of diabetes. Terminal deoxynucleotidyl transferase(Td T)-mediated d UTP nick end labeling(TUNEL)-positive signals co-localized with Ton EBP immunoreactive RGC. These changes were increased in the diabetic retinas compared with controls.CONCLUSION: The present data show that AR and Ton EBP are upregulated in the DR and Ton EBP may contribute to apoptosis of RGC in the DR.
基金Supported by the National Institute of Health under Award Number R01 EY004446&R01 EY019908NIH Vision Core EY02520+1 种基金the Retina Research Foundation(Houston),Research to Prevent Blindness Inc.Hong Kong Polytechnic University grants G-UA7J and G-YBQT
文摘AIM:To investigate the retinal toxicity and pharmacokinetics of simvastatin intravitreally injected into mice.METHODS:Forty-eight 6-8-week-old C57BL/6J mice were used in this study.Simvastatin was intravitreally injected into the right eye of each mouse;the left eye was injected with vehicle and was used as a control.Bilateral dark-adapted electroretinography(ERG)was performed 1 and 7d following injection.Histology was examined using a combination of light,fluorescence and electron microscopy.Highperformance liquid chromatography(HPLC)was used to determine the decay in the retinal simvastatin concentration.RESULTS:ERG revealed no significant changes in the simvastatin-injected eyes compared to control.Histologic studies showed normal retinal morphology in eyes injected with simvastatin up to a final vitreal concentration of 200μmol/L.No significant changes in the number of photoreceptors,bipolar cells or ganglion cells were found.The retinal simvastatin concentration decayed exponentially,with a half-life of 1.92-2.41h.CONCLUSION:Intravitreal injection of up to 200μmol/L simvastatin produced no signs of adverse effects in the mouse retina.Simvastatin reaches the retina shortly after intravitreal injectionand has a short half-life.