AIM:The objective of this study was to investigate the ameliorative effect of Erjing pills(PL)on the functional impairment of the diabetic retinal neurovascular unit(NVU)in rats.METHODS:A diabetic retinopathy(DR)model was established using BN rats,which were then treated with freeze-dried Erjing pills powder.After 12 weeks,various assessments were conducted:retinal thickness was measured using OCT,fundus lesions were evaluated with FFA,and retinal cell structure,arrangement,and layer thickness were analyzed through HE staining.Additionally,transmission electron microscopy was employed to examine ultrastructural changes in retinal ganglion cells(RGCs),and retinal leakage was assessed using EB in vivo perfusion.The expression of ZO-1,a tight junction protein in the retina,was detected via immunohistochemistry,while Western blot analysis quantified the levels of ZO-1,occludin,and claudin-5 proteins in rat retinal tissue.Serum vascular endothelial growth factor(VEGF)levels were measured using an ELISA kit.RESULTS:Results showed that OCT,FFA,HE staining,and transmission electron microscopy indicated a significant reduction in retinal thickness in the MOD group compared to the CON group(P＜0.05).In contrast,the retinal thickness increased in the CDC,PLL,and PLH groups compared to the MOD group,with significant improvement observed in the PLH group(P＜0.05).Additionally,the number of RGCs increased,and sodium fluorescein leakage from fundus mi-crovessels decreased in the CON group relative to the administered groups.Transmission electron microscopy revealed ir-regular deformation of RGC nuclei,mitochondrial reduction and swelling,and organelle loss in the MOD group compared to the CON group.However,the CDC,PLL,and PLH groups demonstrated varying degrees of improvement in cellular layers.EB leakage assay results indicated a significant increase in retinal EB leakage in the MOD group compared to the CON group(P＜0.01).EB leakage was significantly reduced in the CDC group compared to the MOD group(P＜0.01),with some reduction also observed in the PLL and PLH groups(P＜0.05,P＜0.01).Immunohistochemistry and Western blot analyses revealed a significant decrease in the expression of retinal tight junction proteins ZO-1,occludin,and clau-din-5 in the MOD group compared to the CON group(P＜0.05).Protein expression was notably higher in the CDC group compared to the MOD group(P＜0.01),with increases also observed in the PLL and PLH groups(P＜0.05,P＜0.01).ELISA results showed that VEGF levels were significantly higher in the MOD group compared to the CON group(P＜0.01).The CDC,PLL,and PLH groups exhibited varying degrees of reduction in VEGF levels compared to the MOD group(P＜0.05,P＜0.01).CONCLUSION:These findings suggest that PL effectively ameliorates retinal NVU damage in DR rats.

AIM:The objective of this study was to investigate the ameliorative effect of Erjing pills(PL)on the functional impairment of the diabetic retinal neurovascular unit(NVU)in rats.METHODS:A diabetic retinopathy(DR)model was established using BN rats,which were then treated with freeze-dried Erjing pills powder.After 12 weeks,various assessments were conducted:retinal thickness was measured using OCT,fundus lesions were evaluated with FFA,and retinal cell structure,arrangement,and layer thickness were analyzed through HE staining.Additionally,transmission electron microscopy was employed to examine ultrastructural changes in retinal ganglion cells(RGCs),and retinal leakage was assessed using EB in vivo perfusion.The expression of ZO-1,a tight junction protein in the retina,was detected via immunohistochemistry,while Western blot analysis quantified the levels of ZO-1,occludin,and claudin-5 proteins in rat retinal tissue.Serum vascular endothelial growth factor(VEGF)levels were measured using an ELISA kit.RESULTS:Results showed that OCT,FFA,HE staining,and transmission electron microscopy indicated a significant reduction in retinal thickness in the MOD group compared to the CON group(P＜0.05).In contrast,the retinal thickness increased in the CDC,PLL,and PLH groups compared to the MOD group,with significant improvement observed in the PLH group(P＜0.05).Additionally,the number of RGCs increased,and sodium fluorescein leakage from fundus mi-crovessels decreased in the CON group relative to the administered groups.Transmission electron microscopy revealed ir-regular deformation of RGC nuclei,mitochondrial reduction and swelling,and organelle loss in the MOD group compared to the CON group.However,the CDC,PLL,and PLH groups demonstrated varying degrees of improvement in cellular layers.EB leakage assay results indicated a significant increase in retinal EB leakage in the MOD group compared to the CON group(P＜0.01).EB leakage was significantly reduced in the CDC group compared to the MOD group(P＜0.01),with some reduction also observed in the PLL and PLH groups(P＜0.05,P＜0.01).Immunohistochemistry and Western blot analyses revealed a significant decrease in the expression of retinal tight junction proteins ZO-1,occludin,and clau-din-5 in the MOD group compared to the CON group(P＜0.05).Protein expression was notably higher in the CDC group compared to the MOD group(P＜0.01),with increases also observed in the PLL and PLH groups(P＜0.05,P＜0.01).ELISA results showed that VEGF levels were significantly higher in the MOD group compared to the CON group(P＜0.01).The CDC,PLL,and PLH groups exhibited varying degrees of reduction in VEGF levels compared to the MOD group(P＜0.05,P＜0.01).CONCLUSION:These findings suggest that PL effectively ameliorates retinal NVU damage in DR rats.