Ameliorative effect of Panax notoginseng saponins eye drops on non-proliferative diabetic retinopathy in rats
Diabetic retinopathy(DR)is a diabetic ocular complication that can lead to poor vision and blindness.This experiment aimed to investigate the ameliorative effect and its mechanism of Panax notoginseng saponins(PNS)eye drops on streptozotocin(STZ)-induced non-proliferative diabetic retinopathy(NPDR)in rats.All experiments were approved by the Animal Research Committee of Shanghai University of Traditional Chinese Medicine.Animal welfare and the animal experimental protocols were strictly consistent with related ethics regulations of Shanghai University of Traditional Chinese Medicine(No.PZSHUTCM 211115004).Diabetes mellitus was induced by a single intraperitoneal injection of STZ into rats.Two months later,PNS solution was dropped binocular twice per day at 6 h intervals at dose of 20,40,and 80 mg·kg-1 continuously for 1 month.The morphological structure and activation of microglia of the retina were observed by hematoxylin-eosin staining and immunohistochemical assay.The disruption of the blood-retina barrier(BRB)was conducted by the Evans blue dye leakage assay.The number of acellular capillaries in the retina was assessed by digesting and hematoxylin-eosin staining assay.The number of retinal leukocyte adhesion was observed by fluorescein isothiocyanate-coupled concanavalin A lectin labeling assay.The serum expression of inflammatory factors was measured using enzyme-linked immunosorbent assay.Western blot experiments were used to detect the expression of relevant proteins in retinal tissue and transcriptional activation of nuclear factor kappa-B(NF-κB).The results revealed that PNS eye drops significantly increased the thickness of the retina,decreased the number of acellular capillaries,and up-regulated the expression of the tight junction proteins claudin-1 and occludin,thereby alleviating BRB damage.In addition,PNS eye drops were also able to significantly reduce leukocyte adhesion and microglia activation,the expression of inflammatory factors in serum,and the nuclear translocation of retinal p65 proteins,effectively inhibiting the occurrence of retinal inflammation.The above results showed that PNS eye drops played a role in improving NPDR by inhibiting the activation of the NF-κB signaling pathway and reducing inflammation.
NETL
NSTL
万方数据
