Intravitreal injection of ranibizumab and CTGF shRNA improves retinal gene expression and microvessel ultrastructure in a rodent model of diabetes.
Therapeutic modalities targeting vascular endothelial growth factor (VEGF) have been used to treat neovascularization and macular edema. However, anti-VEGF treatment alone may cause up-regulation of connective tissue growth factor (CTGF) in the retina, increasing the risk of fibrosis and tractional retinal detachment. Therefore, in this study, we employ a novel dual-target intervention that involves intravitreal injection of the VEGF inhibitor ranibizumab and a transfection reagent-treated non-viral vector carrying anti-CTGF short hairpin RNA (shRNA) driven by human RNA polymerase III promoter U6. The effects of the dual-target intervention on the expression of VEGF and CTGF and on microvessel ultrastructure were examined in retina of streptozocin-induced diabetic rats. CTGF was significantly up-regulated at week 8 after diabetic induction, whereas VEGF was not up-regulated until week 10. The high expression of both genes was maintained at week 12. Transmission electron microscopy also revealed progressive exacerbation of microvessel ultrastructure during the same period. In addition, ranibizumab significantly lowered VEGF but elevated CTGF mRNA, whereas CTGF shRNA significantly reduced the mRNA levels of both CTGF and VEGF in diabetic retinas. Importantly, dual-target intervention normalized the transcript levels of both target genes and ameliorated retinal microvessel ultrastructural damage better than either single-target intervention. These results suggest the advantages of dual-target over single-target interventions in diabetic retina and reveal a novel therapeutic modality for diabetic retinopathy.
Tianjin Medical University Eye Hospital/Eye Institute, Fukang Rd. 251#, Nankai Dist., Tianjin 300384, China. hbj151617@163.com.
Bojie
B
Hu
Tianjin Medical University Eye Hospital/Eye Institute, Fukang Rd. 251#, Nankai Dist., Tianjin 300384, China. yanzhang9927@163.com.
Yan
Y
Zhang
Tianjin Medical University Eye Hospital/Eye Institute, Fukang Rd. 251#, Nankai Dist., Tianjin 300384, China. m18450073628@163.com.
Qing
Q
Zeng
Tianjin Medical University Eye Hospital/Eye Institute, Fukang Rd. 251#, Nankai Dist., Tianjin 300384, China. hanqian0131@sina.com.
Qian
Q
Han
Tianjin Medical University Eye Hospital/Eye Institute, Fukang Rd. 251#, Nankai Dist., Tianjin 300384, China. zhanglj2004@163.com.
Lijuan
L
Zhang
Tianjin Medical University Eye Hospital/Eye Institute, Fukang Rd. 251#, Nankai Dist., Tianjin 300384, China. tianshi0530@163.com.
Mian
M
Liu
Tianjin Medical University Eye Hospital/Eye Institute, Fukang Rd. 251#, Nankai Dist., Tianjin 300384, China. xiaorli@163.com.
Xiaorong
X
Li
D000818:Animals; D061067:Antibodies, Monoclonal, Humanized / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D055513:Connective Tissue Growth Factor / Q000235:genetics / Q000378:metabolism*; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy* / Q000378:metabolism; D003930:Diabetic Retinopathy / Q000188:drug therapy* / Q000378:metabolism; D057809:HEK293 Cells; D006801:Humans; D056965:Injections, Intraocular; D008297:Male; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D000069579:Ranibizumab; D051381:Rats; D017207:Rats, Sprague-Dawley; D012160:Retina / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure; D012171:Retinal Vessels / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism
D061067:Antibodies, Monoclonal, Humanized; C526316:CCN2 protein, rat; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D042461:Vascular Endothelial Growth Factor A; D055513:Connective Tissue Growth Factor; D000069579:Ranibizumab