Objective
To observe apoptotic and proliferative characteristics of the retinal vascular end othelial cells (RVECs) of the 1～16 weeks diabetic rats and p53 and bcl-2 expressions of the rats,in order to probe the pathogenic mechanism of diabetic retinopathy(DR).
Methods
Models of diabetic Wistar rats were made by alloxan venous injection.The retinal blood vessels were filled by ink,the wholemounts and paraffin-embedded sections of the retinas were made,TUNEL staining and Immunohistochemical ABC staining were used,and light microscopy was taken,in succession.
Results
Apoptosis of the RVECs was not found.Compared with control group,the morphologic features of the RVECs and the structure of the retinal blood vessels remained unchanged.In the period from the 10th to the 16th week,the immunohistochemical stain of PCNA,BrdU,p53,and bcl-2 for RVECs revealed positive results,but there was no any sign of the RVECs stacking and proliferating or new blood vessels forming in the retinas.In control group,the reaction of immunological stain of the aforementioned parameters was negative.
Conclusions
No accelerated apoptosis and proliferation of the RVECs in the 1～16 week diabetic rats happen after alloxan injection.Almost all of the RVECs were stimulated to enter the cell cycle in the 10th week.Expression of p53 and bcl-2 might play an important role in stabilizing the RVECs in early stage of diabetes.
(Chin J Ocul Fundus Dis, 1999, 15: 157-159)
Objective To observe the expression of p53, bcl-2 genes, vascular endothelial cell growth factor（VEGF）, basic fibroblast growth factor（bFGF）, insulin-like growth factor-I （IGF-I）, and the receptors of these factors of retinal vascular endothelial cells (VECs) of 1- to 20-week diabetic rats, and the relationship between the expressions and cell cycle arrest.Methods Retinal sections of diabetic rats induced by alloxan were immunohistochemically stained and observed by light microscopy (LM) and electron microscopy (EM). Dot blotting and Western blotting were used to determine the expression of mRNA, proteins of p53 and bcl-2. Results Under LM, immunohistochemical positive expression of p53 and bcl-2 were found on the vessels of ganglion cell layer and inner nuclear layer of retinae of 8- to 20-week diabetic rats; under EM, these substances were observed depositing in VECs. The retinal VECs also expressed VEGF, bFGF, IGF-I and their receptors. There was no positive expression of other cell types in these retinae, all cell types of retinae in control group, or all cells of retinae of diabetic rats with the course of disease of 1 to 6 weeks. The result of dot blotting revealed that retinal tissue of 20-week diabetic rat expressed p53 and bcl-2 mRNA, and the result of Western blotting revealed that they also expressed p53 and bcl-2 proteins. But retinal tissues of control group did not. Positive expression of bax was not found in the retinae in control group or 1- to 20-week diabetic rats. Conclusion p53, bcl-2 may introduce cell cycle arrest of VECs of retinae in 8- to 20-week diabetic rats. High glucose might stimulate the expression of VEGF, bFGF, IGF-I and their receptors, and the growth factors may keep VECs surviving by self-secretion. (Chin J Ocul Fundus Dis，2003，19：29-33)
Objective
To evaluate glaucoma and anterior chamber angle changes after intravitreal silicone oil injection(SOI).
Methods
The intraocular pressure(IOP) and anterior chamber angles of 34 e yes(33 patients)undergone pars plana vitrectomy and SOI were observed.
Results
Glaucoma occurred in 9 eyes(26%),in which silicone oil glaucoma(SOG) accounted for 77%(7/9).The changes of the superior part of anterior chamber angle were peripheral anterior synechiae in 11 eye(32%) and SO emulsification droplets in 22 eyes(64%) in 1～4.5 months after surgeries.Glaucoma occurred in 6 eyes of 7 eyes undergone peripheral iridectomy at the inferio r part of the iris after the closure of iridectomy holes (plt;0.05).
Conclusion
High incidence of glaucoma was found in this series of patients after intravitreal silicone oil injection,and the main causes of SOG were closure of the inferior iridecomy hole and silicone emulsification.
(Chin J Ocul Fundus Dis, 2001,17:105-107)
Objective To probe a selective cultural method for bovine retinal endothelial cells (BREC) and pericytes (BRP) in vitro.Methods With the isolation of active retinal blood vessels, BREC were cultured in a fibronectin coated substrate and Dulbecco’s Modified Eagle’s Medium (DMEM) supplemented with 10% human serum and 100μg/ml heparin, while homogeneous cultures of retinal pericytes were obtained when isolated microvessels were seeded to uncoated dishes and grown in DMEM supplemented with 20% fetal bovine serum. BREC were identified by acetylated-low density lipoprotein (Dil-Ac-LDL) incorporation and immunohistochemical method of Von Willebrand factor, while BRP were identified by the immunohist ochemical method of α-isoform of smooth-muscle actin. Results The purity of selectively cultured BREC and BRP was more than 98%, being reproducible. BREC got together around the microvessel fragments with the small-cyprinoid-like configuration at first，and could phagocytize Dil-Ac-LDL with the expression of fluorescence in cytoplasm. The expressions of Von Wllebrand factor and α-isoform of smooth-muscle actin were positive and negative in BREC respectively, while were negative and positive in BRP respectively.Conclusion BREC and BRP with high purity can be obtained by using selective culture and coated-dishes respectively which are simple and repeatable methods. (Chin J Ocul Fundus Dis，2004，20：23-26)
Objective To investigate the current situation and developing trend of antithrombotic function study of endothelium in vasculartissue engineering. Methods The effect of several elements onthe antithrombotic ability of endothelium, including the source of endothelium,the characteristic of the matrix materials, the cell culture methods, and the endothelium’s gene modification were analyzed. Results The normal antithrombotic function of tissue engineered vascular relied on the source ofendothelium, gene modification of seeding cells, the cell culture methods in vitro, and the characteristic of the scaffolds. Conclusion The establishment of an ideal antithrombotic functional tissue engineering vascular still requires further studies in various aspects including seeding cells, matrix materials, and cell culture methods. Gene modification of vascular endothelium, which improves the antithrombotic ability, deserves more attention.
Purpose
To investigate the status of proliferation and activation of vascular endothelial cells in preretinal neovascular membranes from patients with insulin dependent diabetetes mellitus(IDDM)by means of immunohistochemical techniques.
Methods
Status of vascular endothelial cells in 18 preretinal neovascular membranes from 18 patients with IDDM was studied by double-immunofluorescence technique and the alkaline phosphataes-anti-alkaline phosphatase(APAAP)technique and compared the findings with the main clinical features of the patients.
Results
Of 18 vascularized membranes,16(88.9%)contained proliferating endothelial cells (positive for proliferating vascular endothelial cell marker EN 7/44) and 14 (77.8%) were positive for endothelial cell activation marker anti-VCAM-1;furthermore,by using a double staining technique,we found that in 14 of the 16 cases(87.5%) the proliferating vascular endothelial cells were activated (expressing VCAM-1).
Conclusion
The proliferation and activation of the vascular endothelial cells of the newly formed vessels in preretinal neovascular membranes suggests the significance of the vascular endothelial cells in the pathophysiology and the progress of proliferative diabetic retinopathy.
(Chin J Ocul Fundus Dis,1998,14:141-143)
Objective To evaluate the relative factors of effect of vitrectomy on corneal endothelial cells. Methods Retrospective analysis of the results of corneal endothelium microscopy performed on 213 eyes of 213 patients undergone vetrectomy operations including single vitrectomy (78 eyes), vitrectomy combined with cataract extraction (135 eyes), silicone oil injection (34 eyes), and C3F8 injection (53 eyes) before and after 1 week, 1 and 3 moths of these surgical procedures. Results There was no significant difference between pre- and postoperative corneal endothelium density in single vitrectomy group and vitrectomy combined with cataract extraction with posterior capsule integrity group (Pgt;0.05). The corneal endothelium density significantly decreased postoperatively in C3F8or silicone oil injection group with broken posterior capsule (Plt;0.05). Conclusion C3F8 and silicone oil may damnify corneal endothelium in patients undergo vitrectom y combined with cataract extraction with broken posterior capsule. (Chin J Ocul Fundus Dis，2004，20：101-103)
Objective
To cultivate human retinal capillary endothelial cells (HRECs) and establish two-dimensional model of human retinal vessels in vitro.
Methods
In a fibronectincoated raising pound, HRECs were cultured by non-serum human-endothelial-cells substrate and two-dimensional model of human retinal vessels was established. Horseradish peroxidase was used to detect the permeability. Some of the vascular models were cultivated with 5 ng/ml vascular endothelial growth factor (VEGF), whose changes of permeability was compared with which of the models without cultivation with VEGF. The effect of VEGF on vascular permeability was observed.
Results
Meshy vascular structure came into being due to the confluent HRECs after 2 to 4 days. Comparatively complete two-dimensional vascular model after about 6 days. VEGF increased vascular permeability and promoted the formation of blood vessels.
Conclusion
HRECs can be cultivated successfully with human-endothelial-cells substrate; standard retinal two-dimensional vascular model in vitro can be established by using cellular raising pound and non-serum human-endothelial-cells substrate.
(Chin J Ocul Fundus Dis, 2006, 22: 110-112)
Objective
To investigate the effect of batroxobin on the blood-retinal barrier (BRB) and vascular endothelial growth factors (VEGF) in diabetic rats.
Methods
Sixty Sprague-Dawley rats were used to establish diabetic models by intraperitoneal injecting with streptozotocin (60 mg/kg), and were divided into 3 groups: diabetic group (n=20), batroxobin (40 mg/kg) group (n=20) and batroxobin (20 mg/kg) group (n=20). Twenty-five else rats were in control group. All of the rats were executed 7 days later. The function of BRB was observed by Evans blue method.
Results
concentration of VEGF protein was detected by enzyme-linked immunoabsorbert assay (ELISA). The results of each group were compared. Results The content of BRB leaked into retina was obvious lower in the control group than which in the other 3 diabetic groups（Plt;0.01）. There was no significant difference of the content of Evans blue between the two groups with different dosage of batroxobin (P＞0.05). The content of Evans blue was lower in the 2 diabetic groups with different dosage of batroxobin than which in the control group (Plt;0.05). The content of VEGF in retina was obviously lower in control group and 2 diabetic groups with different dosage of batroxobin than which in the diabetic group (Plt;0.01), and obviously lower in batroxobin (40 mg/kg) diabetic group than which in the control group (P＝0.01). The content of VEGF in control group and batroxobin (20 mg/kg) diabetic group (P＝0.06) didnprime;t differ much, which occurred similarly in batroxobin diabetic groups with different dosage (P＝0.78).
Conclusions
Batroxobin may alleviate the damage of function of BRB in diabetic rats and reduce the expression of VEGF, which suggests that batroxobin can protect the function of BRB to a certain extent.
(Chin J Ocul Fundus Dis, 2006, 22: 16-19)
ObjectiveTo investigate the effects of smoking combined with intermittent hypoxia on the pathophysiology of lung tissue and thoracic aorta, and the endothelial injury.MethodsTwenty-four rats (SPF, female, six weeks old) were divided randomly into 4 groups (n=6). The control group was given false smoking and normal oxygen exposure, the smoking-exposed group was exposed in smoking, the intermittent hypoxia group was exposed in intermittent hypoxia environment, and the overlap group was exposed to smoking and intermittent hypoxia. After 8 weeks, body weight, right ventricular hypertrophy index (RVHI), the pathological changes of lung tissue and thoracic aorta were measured, and the level of endothelin-1 (ET-1), endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) and stromal cell-derived factor-1α (SDF-1α) in serum of rats were evaluated.ResultsRVHI of rats in the smoking-exposed group, intermittent hypoxia group, overlap group were higher than that in the control group. In addition, RVHI in the overlap group was higher than that in the smoking-exposed group, intermittent hypoxia group (all P<0.05). The levels of ET-1, VEGF and SDF-1α in the serum of the smoking-exposed group, intermittent hypoxia group and overlap group were higher than those in the control group, while the level of eNOS was lower than that in the control group, (all P<0.05), the most significant difference was between control group and the overlap group. Pathological observation of lung tissue and thoracic aorta showed obvious emphysema in the smoking-exposed group and overlap group, which was more obvious in the overlap group than that in the smoking-exposed group (all P<0.05). Lung interstitial inflammatory infiltration, bronchial wall lymphocyte hyperplasia and pulmonary fibrosis were shown in different degrees in the smoking-exposed group, intermittent hypoxia group and overlap group, and the pulmonary arteriole wall showed thickening, fibrosis and peripheral inflammatory infiltration also were found in these groups. Thoracic aorta in the smoking-exposed group, intermittent hypoxia group and overlap group showed different degrees of endothelial cell injury, middle membrane thickening, and collagen fiber hyperplasia. The pathological features of the overlap group were most obvious compared to the other two groups.ConclusionsSmoking and intermittent hypoxia exposure can lead to different degrees of lung tissue and vascular endothelial injury and decrease of vascular endothelial protective factors in rats, resulting in dysfunction of vascular endothelial cells, which leads to the structural remodeling of pulmonary arterioles and aorta, such as thickening, fibrosis, etc. Combined smoking and intermittent hypoxia exposure can lead to more serious pathological damage.
