Bu Shen Yi Jing Fang Recruitment of Peripheral Blood Stem Cells to the Retina of RCS Rats and Expression of Retinal Ciliary Neurotrophic Factor

Abstract

Objective: To measure recruitment of bone marrow-derived mesenchymal stem cells from peripheral blood to the retina of royal college of surgeon (RCS) rats and the expression of ciliary neurotrophic factor (CNTF). We also investigated the mechanism by which Bu Shen Yi Jing Fang (BSYJ) could treat retinal degenerative diseases. Methods: This was an experimental study. RCS rats were injected with 1×107 green fluorescent protein- (GFP-) labeled bone marrow-derived mesenchymal stem cells (GFP-MSCs). The injected rats were assigned to a distilled water group or a BSYJ group according to selection from a random number table, and 39 rats in each group. Each rat in the respective groups was gavaged with either distilled water or BSYJ solution one day after injection. Normal SD rats were treated routinely as the control group. At 7, 14, and 28 days after treatment, retina flat mounts were prepared to assess the recruitment of GFP-MSCs to the retina. Quantitative polymerase chain reaction (Q-PCR) and immunofluorescence double labeling were used to determine the effect of BSYJ on expression of ciliary neurotrophic factor (CNTF) in the retina. Apoptosis of retinal cells was measured by the TUNEL method. Data were analyzed using ANOVA. Results: At 7, 14, and 28 days after treatment, the numbers of GFP-MSCs in the distilled water group were less than in the BSYJ group, and the difference was significant at 28 days (t =2.71, P=0.001). At 7, 14, and 28 days after treatment, CNTF mRNA expression in the BSYJ group was significantly higher than in the distilled water group (F=5.763, P=0.003; F=3.165, P=0.042; F=4.839, P=0.004). At 7 and 28 days after treatment, the apoptosis rate of retinal cells in BSYJ group was significantly less than in the distilled water group (F=0.002, P=0.001; F=0.307, P=0.004). Conclusions: BSYJ improved recruitment of peripheral blood stem cells to the retina and increased CNTF expression. The recruitment of stem cells by BSYJ may delay progression of retinal cell apoptosis and degeneration in RCS rats. Key words: Bu Shen Yi Jing Fang; marrow-derived mesenchymal stem cells; ciliary neurotrophic factor; retinitis pigmentosa