Effect Of Bu Shen Yi Jing Fang On Rescuing Dry Age-related Macular Degeneration By Motivating Endogenous Bone Marrow-derived Stem Cells

Objective:Dry age-related macular degeneration is the main blinding eye disease in developed countries for people above 65 years.It belongs to the category of retinal degenerative diseases.The pathology of retinal degeneration is the irreversible damage of retinal neurons,and there is no effective treatment available currently.In recent years,the emergence of cell replacement therapy makes it possible to rescue retinal degenerative diseases.New research shows that mobilized endogenous BMCs can also repair tissue damage,and the method is more safe and feasible compared with cell transplantation.Therefore,promoting the mobilization of BMCs,its homing and directional differentiation at damage area may become new strategies of stem cell therapy.Bu Shen Yi Jing Fang is the commonly used basic formula for dry AMD treatment.This project is designed on the basis of clinical observation to thoroughly investigate the effect and effect targets of Bu Shen Yi Jing Fang on repairing retinal degeneration damage through motivating endogenous bone marrow stem cells,thus to supply reliable and scientific evidence for clinical application.Methods:1.Sodium iodate induced dry-AMD C57 mouse was used as an animal model.The model mice were randomly divided into two groups:the control group(distilled water)and the BSYJ group(14.17g/kg),while normal C57 mice were used as normal control group.Start intragastric administration at the first day after modeling,the electroretinograms(ERGs)and HE staining were used to measure the functional and histopathological changes of the retina at 7d,14d and 28d after treated,respectively.2.Modeling,grouping and administrative methods are as same as part 1.Fluorescence-activated cell sorting(FACS)was used to measure the number of BMCs in peripheral blood(PB),while ELISA assay kits were used to detect the levels of G-CSF,SDF-la and CXCR-4 in PB at 7d,14d and 28d after treated.3.Modeling,grouping and administrative methods are as same as part 1.At the first day after modeling,give intravenous injection of mouse bone marrow stem cells(BMCs)marked with green fluorescent protein(GFP).ELISA assay employed to detect the levels of SDF-1?and CXCR-4 both in PB and retina.Western blot assay was used to measure the protein expression of ICAM-1 and FN in retina,and the GFP-BMCs were observed in mice flatmount retinas.4.Modeling,grouping and administrative methods are as same as part 3.RT-PCR was used to detect the mRNA expression of bFGF,CNTF and BDNF in retin.Results:1.ERGs results showed that BSYJ groups showed significant improvements of amplitudes of photopic ERG at 7d,14d and 28d(P<0.05),while amplitudes of scotopic ERG,Ops and 3.0 flicker improved significantly at 28d(P<0.05).HE results showed the morphology and quantity of retinal photoreceptor cells were significantly improved after treatment for 14d and 28d(P<0.05).2.FACS of BMCs in PB showed the number of BMCs increased significantly at 7 d after BSYJ treated(P<0.05).ELISA results showed the levels of G-CSF,SDF-la and CXCR-4 in serum increased significantly at 7d,14d and 28d after BSYJ treated(P<0.05).3.In flatmount retinas,the number of GFP-BMCs significantly increased at 7d,14d and 28d after BSYJ treated(P?0.01).ELISA results indicated the levels of SDF-1a and CXCR-4 increased significantly both in PB and retina at 14d and 28d after BSYJ treatments(P<0.01).Western blot analysis showed a significant increase of ICAM-1 expression in the retina at 7d,14d and 28d after BSYJ treatments(P<0.05),while the expression of FN increased at 14d and 28d as well(P<0.05).4.RT-PCR analysis showed there was a significant increase of CNTF in the retina of mouse that received BSYJ for 7d,14d and 28d(P<0.05),while BDNFand bFGF was also significantly increased at 7d,14d and 28d after treated of BSYJ(P<0.05).Conclusion:1.BSYJ has a protective effect on dry-AMD and can delay the progression of it.2.BSYJ has the mobilization effect on BMCs in sodium iodate induced dry-AMD mice model,which may be related to increased C-GSF expression and activation of the SDF-1/CXCR-4 signal axis.3.BSYJ can promote BMCs homing to the injury of the retina,that is probably due to the increase of adhesion molecule ICAM-1 and FN expression.4.BSYJ can delay the dry-AMD pathological changes,which may be related to increased homing of BMCs and secretion of CNTF,BDNF and bFGF.