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Objective To investigate the expression of 6-phosphofructo-2-kinase /fructose-2,6-bisphosphatase-3 (PFKFB3) and sphingosine 1-phosphate receptor 2 (S1 P2) in the retina of rats with type 2 diabetes mellitus (DM) and to explore the correlation of tertiary butylhydroquinone (tBHQ) with PFKFB3 and S1P2.Methods Together 60 male SD rats were divided into normal control group (NC group),diabetes mellitus group (DM group) and tBHQ group.Type 2 DM model was induced in the latter two groups.The rats in tBHQ group were given 10 g · L-1 tBHQ in high-fat and highsugar diet 1 week after successful modeling,while DM rats were fed with high-fat and high-sugar diet continuously.At 4 weeks and 12 weeks after tBHQ intervention,blood samples were taken from the hearts of rats in each group,and serum contents of fasting plasma glucose (FPG) and fasting serum insulin (FINs) were measured.Immunohistochemistry and qRT-PCR were taken to detect the distribution and expression of PFKFB3,S1 P2 and vascular endothehal growth factor (VEGF) mRNA and protein in the retina,and TUNEL methods were used to detect apoptosis index of retinal ganglion cells of rats in each group.Results There were significant difference in the FPG and FINs levels of the three groups at 4 weeks and 12 weeks (all P =0.000).Light microscopy test showed that positive expressions of PFKFB3,S1 P2 and VEGF protein were found in all groups at 4 and 12 weeks,which were mainly located in the retinal ganglion cell layer and the inner nuclear layer.Immunohistochemistry and qRT-PCR showed that the difference in relative expressions of PFKFB3,S1P2,VEGF protein and mRNA in the retina at different times after modeling were statistically significant (all P ＜ 0.05).At 4 and 12 weeks,the expression levels of PFKFB3,S1P2 and VEGF in DM group were higher than those in NC group,but their expressions in tBHQ group were significantly downregulated when compared with DM group,and all differences were statistically significant (all P ＜ 0.05).Compared with 4 weeks,PFKFB3,S1 P2 and VEGF mRNA and protein in DM group were overexpressed at 12 weeks,and the expression level of S1 P2 in tBHQ group at 12 weeks was lower than that at 4 weeks,and the differences were statistically significant (all P ＜ 0.05).TUNEL assays showed that there was significant difference in the apoptotic index (AI) of retinal ganglion cells of rats in each group at different times after modeling (all P ＜ 0.05).DM group had higher AI than NC group (P ＜ 0.05),and tBHQ group was lower than DM group (P ＜ 0.05);Compared with 4 weeks,DM group had increased AI at 12 weeks while tBHQ group had decreased AI (both P ＜ 0.05).Conclusion PFKFB3,S1P2 and VEGF are involved in the pathological process of the retina of type 2 DM rats,which may play a role through the PFKFB3 / VEGF / S1P2 signaling pathway and may be related to the apoptosis of retinal ganglion cells.And it is indicated that tBHQ has a protective effect on the retina of type 2 DM rats.
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BACKGROUND: Repair of tendon interface is a difficulty in orthopedics and sports medicine, and the formation of new bone is conducive to its healing. Calcitonin gene-related peptide (CGRP) plays a critical role in tissue homeostasis and repair, but its effect on the bone-tendon interface repair is unknown. OBJECTIVE: To investigate the effect of CGRP on the expression of osteocalcin and to evaluate the effect of CGRP on the early healing of rotator cuff injury in a mouse model. METHODS: A mouse model of supraspinatus insertion-humerus injury was created. All model mice were then randomized into two groups, and given the injection of 5 nmol/kg CGRP (experimental group) or same volume of normal saline (control group) through the glenohumeral joint immediately after operation, thrice weekly, for 2 weeks. The mice were sacrificed at postoperative 4 and 6 weeks to remove the rotator cuff samples for hematoxylin-eosin staining and biomechanical test. The mRNA and protein expression levels of osteocalcin were surveyed by qRT-PCR, immunohistochemistry, and western blot assay. RESULTS AND CONCLUSION: At postoperative 4 and 6 weeks, the mRNA and protein expression of osteocalcin in the experimental group were significantly higher than those in the control group (P < 0.05). Compared with the control group, there were more fibrocartilages in the experimental group at 4 weeks postoperatively, and more new bone formation in the experimental group at 6 weeks postoperatively. At 4 weeks postoperatively, failure load in the experimental group increased slightly, but it was not significantly different from that in the control group (P > 0.05); at 6 weeks postoperatively, failure load in the experimental group was significantly higher than that in the control group (P<0.05). To conclude, local injection of CGRP can up-regulate the expression of osteocalcin and the formation of new bone at the injury site, which can enhance early healing the injured rotator cuff.
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AIM: To establish an experimental model of high intraocular pressure in mice by laser photocoagulation and to prepare for future research. METHODS: Experimental model of high intraocular pressure was induced unilaterally in 44 C57BL/6 mice. The fellow eye served as a control. TONO-PEN AVIA Tonomter was used to measure intraocular pressure (IOP) to guarantee IOP value at 1, 2, 4, 8wk. Slit-lamp biomicroscopy was performed throughout the period and the structural changes were assessed histologically. And then, their eyes were enucleated, postfixed, cryoprotected, and embedded in optimal cutting temperature medium. After hematoxylin and eosin stain ( HE stain ) , cryosections of the retina were observed under light microscope. TdT-mediated biotin-dUTP nick end labeling ( TUNEL ) was performed on the retinal sections to determine apoptosis rate. RESULTS: IOP of laser-treated eyes was significantly higher than that of control eyes from 1-8wk (P CONCLUSION: The laser photocoagulation of limbus causes chronic elevation of IOP and this method may be a promising experimental model for the investigation of biological mechanisms of glaucomatous retinal ganglion cell damage.
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AlM:To construct recombination eukaryotic expression plasmid of human thyrotropin receptor extracellular domain encapsulated with cationic liposomes. METHODS:We amplified the target gene of shuttle vector PHMCMVTSHR289, conjugated the target gene and eukaryotic expression plasmid pcDNA3. 1 +, and accredited whether pcDNA3. 1+/TSHR289 was connected or not by enzymatic digestion and sequencing. Cationic liposomes encapsulated the recombination plasmid pcDNA3. 1+/TSHR289. RESULTS: Recombination plasmid pcDNA3. 1+/TSHR289 digested with enzyme Hindlll and the fragment through 0. 8% gel electrophoresis showed 512bp strip. Recombination plasmid pcDNA3. 1+/TSHR289 were found synonymous mutation through forward ( AAC to AAT ) and reverse sequencing ( GCG to GCT) . The volume ratio of cationic liposomes and recombinant plasmid was 3:1. CONCLUSlON: lt is successful to construct the recombination plasmid pcDNA3. 1+/TSHR289 by accredit it through enzymatic digestion and sequencing.
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Background As one of the most common microvascular complication of diabetes in eyes,diabetic retinopathy (DR) is one of the most important cause of blindness.Nuclear factor-kappa B (NF-κB) is involved in the occurrence and development of the disease through the activation of a series of inflammatory cytokines.Objective The present study was to investigate the effects of peroxisome proliferator-activated receptor-gamma (PPAR-γ) excitomotor,rosiglitazone,on NF-κB expression and apoptosis of the retinal ganglion cells (RGCs) in the retina with diabetes mellitus. Methods Ninety SPF male Wistar rats were randomized into normal control group,diabetic control group and rosiglitazone group.Diabetes mellitus was induced by intraperitoneal injection of 50 mg/kg streptozotocin(STZ).Then 3 mg/kg rosiglitazone was intragastricly administered once per day in the rosiglitazonegroup,and the same volume of saline solution was used at the same way in the normal control group and diabetic control group from 3 days after modeling.The rats were sacrificed and the eye cups specimen was made at 4,8 and 12 weeks after usage of drugs.Retinal histopathological examination was performed by hematine-eosin staining,and expression of NF-κB p65 protein in retina and apoptotic index(AI) of RGCs were detected by immunohistochemistry and TUNEL assay,respectively in different time points mentioned above.The use of the animals complied with the Regulations for the Administration of Affairs Concerning Experimental Animals by State and Technology Commission.Results The blood glucose level was significantly elevated at various time points in the diabetic control group and rosiglitazone group compared with normal control group (P＜0.01 ),and that of the rosiglitazone group was significantly declined in comparison to the diabetic control group (q =0.81,0.82,1.23,P＞ 0.05 ).Normal retinal structure was seen in the normal control group,and edema retinal cell and disorder of retinal layers were exhibited in the diabetic control group.Retinal structure was almost normal in the rosiglitazone group.The NF-κB p65 was expressed weakly in the retina of normal control group,but the expression of NF-κB p65 was significantly elevated in the diabetic control group and rosiglitazone group compared with the normal control group(P＜0.01 ).However,the expression of NF-κB p65(A value)was significantly decreased in the rosiglitazone group compared with diabetic control group at 8 weeks and 12 weeks( q=17.77,15.30,P＜0.01 ).There were a few apoptotic cells in rat retina of the normal control group.Compared with the normal control group,the AI of the diabetic control group and rosiglitazone group was significantly reduced(P＜0.01 ).However,the AI of RGCs in the rosiglitazone group was significantly lower than that of diabetic control group in various time points (q =19.28,27.39,49.92,P＜0.01 ). Conclusions As one of the PPAR-γexcitomotors,rosiglitazone can inhibit apoptosis of RGCs through downregulating the expression of NF-κB in rat retina with diabetes mellitus,indicating a protective effect of rosiglitazone on retina in diabetic rat.