In order to study the expression change of insulin-like growth factor-1 (IGF-1) and its receptor genes in different generations of tendon cell in culture, Dig-labeled synthesized oligonucleotide probes were used to detect the mRNA expression in primary, 6th and 13th generation of tendon cell. The results showed that IGF-1 receptor mRNA was expressed in all of the 3 above generation tendon cells. IGF-1 mRNA was expressed only in primary and 6th generation cells. Tendon cell of 13th generation did not express IGF-1 mRNA. It might suggest that the absence of IGF-1 mRNA expression be one of the causes which led to the decrease of reproductive ability of 13th generation tendon cell.
Objective To evaluate the inhibiting effect of adenosine on rat retinal ganglion cells (RGC) death induced by P2X7 and N-methyl-D-aspartate (NMDA) receptor. Methods (1) Long-Evan neonatal rats were back labeled with aminostilbamidine to identify RGC. The viability of RGC affected by P2X7 excitomotor BzATP (50 mu;mol/L), glutamate receptor excitomotor NMDA (100 mu;mol/L) and adenosine (300 mu;mol/L) was detected. (2) RGC from the retinae of unlabeled neonatal rats were cultured in vitro. After labeled with Fura-2 methyl acetate, an intracellular calcium indicator, the effect of BzATP, NMDA and adenosine on intracellular Ca2+ level was detected byCa2+ imaging system. Results Both BzATP (50 mu;mol/L) and NMDA(100 mu;mol/L) could kill about 30% of the RGC. Cell death was prevented by adenosine (300 mu;mol/L) with the cell viability increased from (68.9plusmn;2.3)% and (69.9plusmn;3.2)% to (91.2plusmn;3.5)% (P<0.001) and (102.1plusmn;3.9)% (P<0.001), respectively. BzATP (50 mu;mol/L) led to a large, sustained increase of intracellular Ca2+ concentration to (1183plusmn;109) nmol/L. After the adenosine intervened, Ca2+ concentration increased slightly to (314plusmn;64) nmol/L (P<0.001). Conclusion Adenosine may prevent RGC death and increase of intracellular Ca2+ concentration from P2X7and NMDA receptor stimulation. (Chin J Ocul Fundus Dis, 2007, 23: 133-136)
Proliferative vitreoretinopathy (PVR) is a common complication and major cause of blindness of ocular trauma. Many cytokines, including vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF), participate in the process of the pathogenesis of traumatic PVR. VEGF competitively inhibits binding of PDGF to its receptor (PDGFRα), enables indirect activation of PDGFRα by non-PDGF ligands, resulting in reduced p53 expression, cell proliferation and migration, which is a key point in the pathogenesis of traumatic PVR.
Objective To investigate the activation and role of signal transduction pathway of epidermal growth factor (EGF)-epidermal growth factor receptor (EGFR)-mitogen activated protein kinase (MAPK) in proliferation of human retinal pigment epithelial (RPE) cells. Methods Human RPE cells were stimulated with 0.1%,10% foetal calfserum (FCS) and EGF(0.1, 1, 10, 50 and 100 ng/ml)in 0.1% FCS Dulbeco′s modified Eagle′s medium (DMEM) and in 10% FCS DMEM for 3 days, respectively. Immunohistochemical staining and in situ hybridization were used to observe the expressions of EGFR protein and EGFR mRNA,respectively. Activation of MAPK was detected by immunohistochemical method with specific anti-phosphorylated ERK 1/2 antibody. Results The optimal concentrations of EGF were 10 ng/ml in 0.1% FCS DMEM and 1 ng/ml in 10% FCS DMEM. After 3 days of stimulation with EGF, phosphorylated ERK 1/2 staining was detectable in nucleus of RPE cells, whereas cells presented immunostaining for phosphorylated ERK 1/2 in the cytoplasm before stimulation. Conclusions EGF may improve the expression of EGFR protein and EGFR mRNA of RPE cells, and induced MAPK nuclear translocation in a concentration-dependent manner. EGF-EGFR-MAPK signal transduction pathway may play a key role in RPE cells proliferation, and serum exerts an important acceclerating function in the process. (Chin J Ocul Fundus Dis,2004,20:67-132)
Objective Aseptic loosening of prosthesis is associated with peri prosthetical osteolysis caused by osteoclast activation. Receptor activator of nuclear factor kappa B (NF-κB) l igand (RANKL)/receptor activator of NF-κB (RANK) signalpathway is fundamental in osteoclast activation. To determine whether RANKL antibody can inhibit inflammatory osteolysis in a osteolysis model of mouse. Methods Sixty female BALB/c mice (aged 8-10 weeks, weighing 18-20 g) were selected. The skull bone piece was harvested from 20 mice as the donor of bone graft; the subcutaneous air pouches (2 cm × 2 cm) models were established on the back of the other 40 mice and the skull bone piece was inserted into the air pouches. The 40 mice were equally divided into groups A (negative control group), B (positive control group), C (low-dose RANKL antibody group), and D (high-dose RANKL antibody group). At 1 day after bone graft, 0.5 mL PBS was injected into the pouch of group A, 0.5 mL PBS containing titanium particle into groups B, C, and D. At 2 days before the titanium particle was injected, RANKL antibody (0.1 mL) were injected into the pouch of group C (50 μg/mL) and group D (500 μg/mL), respectively every day for 2 days, and 0.1 mL PBS into groups A and B. At 14 days after bone implantation, the pouchmembranes containing implanted bone were harvested for gross observation and histological analyse. Results All mice survived to the end of experiment, and incisions healed well. The gross observation showed that inflammatory responses, exudation, and vascular proliferation were obvious in group B, and were inconspicuous in groups A, C, and D. The histological analysis showed that significantly more infiltration of inflammatory cells, more obvious bone resorption, more bone collagen loss, and more positive staining area were observed in group B than in groups A, C, and D. There were significant differences in inflammatory cell number, pouch membrane thickness, bone collagen loss, and osteoclast content between group B and groups A, C, and D (P lt; 0.05). Conclusion RANKL antibody can directly blockRANKL/RANK signal pathway, which is an efficient therapy to inhibit bone absorption associated with implant wearing particles.
Objective To observe the expression of erythropoietin (EPO) and EPO receptor (EPOR) in detached retina in rat model. Methods Fourty-eight male SD rats were randomly divided into control group and retinal detachment (RD) groups (1 hour, 3, 6, 12, 24, 48, and 72 hours group) with 6 rats (12 eyes) in each group. 1.4% hyaluronic acid was slowly injected into the subretinal space to induce the detachment of the upper retina to set up the RD model. The expression levels of mRNA and protein of EPO and EPOR were measured by RT-PCR and western-blotting analysis. Meanwhile, the locations of EPO and EPOR in retina were checked by immunohistochemistry. Results Both of the mRNA and protein levels of EPO and EPOR increased after RD, and reached the peak at the 48th hour after RD. The mRNA levels of EPO and EPOR were significantly higher in the 6 and 12 hours group than that in the control group(Plt;0.05). The protein levels of EPO and EPOR were significantly higher in 3 hours group than that in the control group(Plt;0.05). Immunohistochemistry indicated weak expression of EPO from ganglion cell layer to inner and outer segment of photoreceptor cells, and b expression in the corresponding location was found 48 hours after RD. Expression of EPOR from ganglion cell layer to inner segment of photoreceptor cells in the normal retina was detected, and b expression in the corresponding location was found 48 hours after RD. Conclusion The expression of EPO and EPOR in retina increases gradually after RD, and reaches the peak at the 48th hour; most of the layers of neural retina can express EPO and EPOR.
As most patients of central serous retinopathy (CSC), the symptoms of acute onset will alleviate by oneself after 4-6 months. About 30%-50% of patients with CSC experience chronic or recurrent cases. Resulting in persistent neurosensory detachments and subretinal fluid, causing significant vision loss. Mineralocorticoid receptor (MR) is a kind of nuclear hormone receptors, plays a role in theregulation of water and electrolyte balance. Excessive MR signaling is associated with many diseases. Study found that MR antagonists decreased the thickness of the retina and improved in vision, there was no serious adverse reactions during the period of treatment for chronic CSC. Initial dose of MR antagonists was 25 mg per day, 1 week later, dosage was increased to 50 mg per day, and treatment for about 3 months. There is no conclusive effective treatment and the dosage are still unknown. MR antagonists may be a safe and effective way to treat chronic CSC, though evidence is scant. Prospective, multicenter, large-scale trials is required.
Objective To investigate the role of adenosine A2A receptor plays in retinal pathological neovascularization in mice. Methods A total of 202 mice were divided into room-air group (n=66) and oxygen induced retinopathy (OIR) group (n=136). Among room-air group, there were 18 A2A knock-out (KO) mice (KO subgroup) and 24 C57BL/6 mice as wide type (wide type subgroup). OIR group were divided into OIR control subgroup (n=48), A2A-OIR subgroup (n=24) and Caffeine-OIR subgroup (n=64). The retinal neovascularization of OIR group was induced by oxygen. The pathological neovascularization was determined by retinal sections. Fluorescent quantitative polymerase chain reaction (PCR) was used to measure the mRNA expression of A2A and vascular endothelial growth factor (VEGF). 0.1, 0.3, 1.0 g/L Caffeine was dissolve in drinking water of lactating females in Caffeine-OIR subgroup, non-perfusion areas of retina in mice at the age of 0 - 17, 0 - 7, 7- 17, 7-12, and 12- 17 days were analyzed in different dosage and when the dosage as 1.0 g/L. Results Compared with OIR control subgroup, the retinal non-perfusion areas and the numbers of endothelial cell nuclei breaking through the internal limiting membrane in A2A- OIR subgroup were reduced significantly (t=7.694, 7.747;P<0.001). Compared with wide type subgroup, the level of A2A and VEGF mRNA in OIR control subgroup increased significantly (t=4.036, 2.230;P<0.05). Compared with OIR control subgroup, the level of VEGF mRNA in A2A- OIR subgroup decreased significantly (t=3.122,P<0.01). Compared with OIR control subgroup, the retinal non-perfusion areas in mice at the dosage of 0.1 and 1.0 g/L (t=2.397, 4.533) and at the age of 0 -17, 0 -7 days when the dosage as 1.0 g/L (t=4.070, 2.399) were reduced significantly (P<0.05). Conclusions The expression of adenosine A2A receptor increases in oxygen-induced retinal pathological neovascularization. Adenosine A2A receptor may regulate the expression of VEGF. A2A receptor inactivation can inhibit oxygen-induced retinal pathological neovascularization.
【Abstract】ObjectiveTo investigate the effects of cholecystokinin (CCK) on diabetes mellitus with cholecystolithiasis. MethodsRelevant literatures of recent years were reviewed. ResultsCCK exists widely in human body.On the one hand, CCK enhances cholecystolithiasis by causing diabetes. On the other hand, its pathological changes can also lead to cholecystolithiasis. Besides, it is possibility that the CCKrelated gene abnormality is the common cause of diabetes and cholecystolithiasis. ConclusionCCK plays an important role in diabetes mellitus complicated with cholecystolithiasis. However, there is much yet to be known about CCK.
ObjectiveTo investigate the effects of migration and expression from chemokine receptor 4 (chemokine receptor-4, CXCR4) of rat bone marrow mesenchymal stem cells (BMSCs) which were pretreated by atorvastatin (ATV) in vitro.MethodsIsolated, cultivated, identified the BMSCs, pretreated P4-P6 of BMSCs with different concentrations of ATV for 12 hours. The experimental group was divided into control group, 0.1 nM/L (group 0.1 nM), 1 nM/L (1 nM group), 10 nM/L (10 nM group), 100 nM/L (100 nM group), 1 000 nM/L (1 000 nM group). The mRNA and protein of CXCR4 were determined by real time-polymerase chain reaction and Western blot. Immunofluoreseence assay were used to detect the expression levels of CXCR4. The migration ability of BMSCs were measured by transwell chamber.ResultsImmunofluoreseence assay showed the protein level of CXCR4 of group 1 nM and 10 nM were significantly higher than the other group. RT-PCR and Western blot showed the protein and mRNA level of CXCR4 in 10 nM was higher than that in group 1 nM. The migration ability of group 10 nM was higher than 1 nM and control group.ConclusionsATV can be dose-dependent promote expression levels of CXCR4 of BMSCs cultivated in vitro.