ABSTRACT
[ Abstract] Objective To study the effect of sulodexide on the repair of diabetic retinopathy and the regulation of MAPK pathway in rats. Methods Totally 72 rats were randomly divided into normal control group, diabetic retinopathy group, low, middle and high dose of sulodexide group and metformin hydrochloride group. Except normal control group, other rats were intraperitoneally injected with streptozotocin to establish the rat model of diabetic retinopathy. Rats in the low, middle and high dose sulodexide groups were given sulodexide by intragastric administration of 10 mg / kg,20 mg / kg and 40 mg / kg, respectively. Metformin hydrochloride group was given metformin hydrochloride of 200 mg / kg, once a day for 12 weeks. The levels of fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c) and serum levels of advanced glycation end products (AGEs), interleukin-6 (IL-6), IL-1β, and levels of glucose transporter 1 (GLUT-1), glucose transporter 3(GLUT-3), superoxide dismutase (SOD) and malondialdehyde (MDA) in retina were detected. The levels of p38 MAPK and phosphorylated p38 MAPK (p-p38 MAPK) in retina were detected by immunohistochemistry and Western blotting. Retinal pathological changes and ganglion cell count were examined by HE staining. Results The levels of FBG and HbA1c, serum AGEs, IL-6, IL-1 β, GLUT-1, GLUT-3, MDA and p38 MAPK mRNA, p38 MAPK, p-p38 MAPK / p38 MAPK and immunohistochemical integral optical density of retina in sulodexide group were significantly lower than those in diabetic retinopathy group (P < 0. 05), while the SOD level and ganglion cell number in retinal tissue were significantly higher than those in diabetic retinopathy group (P < 0. 05) . Conclusion Sulodexide can regulate blood glucose level and retinal glucose metabolism in diabetic retinopathy rats, and repair retinal pathological damage, and its mechanism may be related to the regulation of MAPK pathway.
ABSTRACT
AIM:To investigate whether ceramide kinase-like protein(CERKL)alleviates oxidative stress injury of retinal pigment epithelial(RPE)cells induced by blue light via activating the silent information regulator 1(SIRT1)/E2F transcription factor 1(E2F1)axis. METHODS:Cultured human retinal pigment epithelial-19(ARPE-19)cells were irradiated with blue light to observe the morphological changes, and the expression of CERKL was detected by PCR and Western blot. ARPE-19 cells were transfected with siRNA-CERKL and pcDNA3.1-CERKL respectively. After exposure to blue light, cell viability was determined by MTT assay, apoptosis was detected by TUNEL assay, content of oxidative stress markers and the expression of SIRT1/E2F1 axis was analyzed. Then siRNA-SIRT1 was transfected into ARPE-19 cells, and the oxidative stress damage of ARPE-19 cells under blue light irradiation was detected again.RESULTS:ARPE-19 cells gradually contracted into spheres and appeared vacuoles after exposure to blue light. Blue light irradiation led to the increase of CERKL expression level(P<0.05), meanwhile, the rate of cell viability was decreased(P<0.05), the rate of the apoptosis was increased(P<0.05), contents of reactive oxygen species, malondialdehyde and 8-hydroxydeoxyguanosine were increased(P<0.05). Silence of CERKL aggravated this phenomenon, while up-regulation of CERKL could alleviate this change(P<0.05). Up-regulation of CERKL also activated the expression of SIRT1 and promoted the deacetylation of E2F1(P<0.05). Silencing SIRT1 could reverse the alleviating effect of up-regulating CERKL on oxidative stress injury of ARPE-19 cells induced by blue light(P<0.05). CONCLUSION: CERKL can reduce oxidative stress damage of ARPE-19 cells induced by blue light via activating SIRT1 expression and promoting the deacetylation of E2F1.