摘要
Objective To investigate the possible involvement of erythropoietin （EPO）/erythropoietin receptor （EPOR） system in neovascularization and vascular regeneration in diabetic retinopathy （DR）. Methods EPOR positive circulating progenitor cells （CPCs： CD34^＋） and endothelial progenitor cells （EPCs： CD34^＋KDR^＋） were assessed by flow cytometry in type 2 diabetic patients with different stages of DR. The cohort consisted of age- and sex-matched control patients without diabetes （n=7）, non-prolif- erative DR （NPDR, n=7）, proliferative DR （PDR, n=8）, and PDR complicated with diabetic nephropathy （PDR-DN, n=7）. Results The numbers of EPOR^＋ CPCs and EPOR^＋ EPCs were reduced remarkably in NPDR corn pared with the control group （both P（0.01）, whereas rebounded in PDR and PDR-DN groups in varying degrees. Similar changes were observed in respect of the proportion of EPOR^＋ CPCs in CPCs （NPDR vs. control, P（0.01） and that of EPOR^＋ EPCs in EPCs （NPDR vs. control, P〈0.05）. Conclusion Exogenous EPO, mediated via the EPO/EPOR system of EPCs, may alleviate the impaired vascular regeneration in NPDR, whereas it might aggravate retinal neovascularization in PDR due to a rebound of EPOR^＋ EPCs associated with ischemia.
基金
Supported by Sciences and Technology Commission of Shanghai Municipality (08ZR1422100 and 08410701200)
