ObjectiveTo investigate the effect of basic fibroblast growth factor (bFGF) on expression of apoptosisrelated genes in retinal ischemiareperfusion injury (RIRI).MethodsTwentyeight rats were divided into normal, ischemia and treatment group randomly; and the latter two groups were subdivided into 6 subgroups according to different time points: 1 hour, 6, 12, 24, 48, and 72 hours after reperfusion. The rats′ model of experimental RIRI was established. After intravitreously injected with bFGF (treatment group) or balanced saline solution (ischemia group), the expressions of wide type p53 (WTp53)，c-fos, and c-jun in each subgroups were detected by streptavidinbiotin complex of immunohistochemistry.ResultIn ischemia group, the expression of WTp53,c-fos and c-jun was found 6 hours after reperfusion, reached the peak at the 24th hour after reperfusion, kept expressing bly at the 48th hour, and decreased obviously at the 72nd hour. In treatment group, the rule of changes of expression of WTp53, c-fos and c-jun was similar to which in ischemia group, except that the expression amount was obvious decreased. There was statistical significance of the expression of WTp53, c-fos and c-jun between the ischemia and treatment group 6-48 hours after reperfusion (P＜0.05）. ConclusionThe expression of WTp53,c-fos,and c-jun in retinal ganglion cell layer and inner nuclear layer may increase led by RIRI；WTp53,c-fos,and c-jun may be involved in the generant mechanisms of RIRI by playing parts in apoptosis；bFGF can inhibit the increase of expression of WTp53,c-fos,and c-jun in RIRI.Thus, which may has therapeutic effect on RIRI.( Chin J Ocul Fundus Dis,2005,21:310-313)
Objective To investigate the damage to the retinal cells and apoptosis of retinal cells of rats after ischemia-reperfusion insult. Methods The retinal ischemia-reperfusion model was developed by increasing intraocular pressure to 109725 mm Hg in rat eyes. Morphological changes of the rat eyes were observed by means of routine histopathology with HE staining. Apoptosis of the retina was assayed by both DNA fragmentation gel-electrophoresis and terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labelling (TUNEL). Results Compared with the normal control, no histopathological changes were revealed in the rat retinas 30 min after the ischemia and then reperfued for 24 h or 48 h. Retinal ganglion cell layer (RGL) and inner plaxiform layer (IPL) of the retina were observed, however, to become significantly thinner 60 min after the ischemia and then reperfued for 24 h or 48 h. Together with the pathological changes DNA ladder pattern was detected in the same group of the rats. Further, immunochemical stain of the eye demonstrated that TUNEL positive cells were localized in RGL and IPL of the retina. Conclusion Ischemia-reperfusion insult of the eye may remarkably damage the retina of the rat eye. The damage to the retinal cells is mainly localized within RGL and IPL and apoptosis is the important mechanism of the retinal disorder. (Chin J Ocul Fundus Dis, 2002, 18: 296-298)
Objective To elucidate the protective effect of leukocyte depletion on the myocardium during the settings of myocardial reperfusion injury. Methods Twenty patients undergoing cardiopulmonary bypass with continuous infusion of blood cardioplegia were randomized into two groups:the control group (n=10) with no leukocyte depletion filter used, and the experimental group (n=10) with the use of leukocyte depletion filter on the bypass circuit. The blood cells count before and after the filtration were measure...
ObjectiveTo study the relationship between hepatocellular apoptosis and glycogen contents during hepatic cold preservationreperfusion and its mechanism.MethodsBased on the model of four groups of rabbit livers with different hepatocellular glycogen contents, hepatocellular apoptosis and bax gene expression were observed during hepatic cold preservationreperfusion.ResultsApoptotic hepatocytes were obviously found in 60 minute reperfusing livers subsequent to 9 hour cold storage, and there was significant difference in the numbers of apoptotic hepatocytes among all the groups. In the same time, there was the close relationship between the levels of bax gene expression and the glycogen contents of hepatocytes.ConclusionIntracellular abundant glycogen may significantly depress the hepatocellular apoptosis during hepatic cold preservationreperfusion by decreasing hepatocellular bax gene expression.
The classical Hippo pathway leads to the phosphorylation of downstream effector molecules Hippo-Yes-associated protein (Yap) and transcriptional coactivator PDZ-binding motif (Taz) serine sites through a kinase response, thereby promoting cell proliferation, controlling cell polarity, changing cytoskeleton, it plays an important regulatory role in various pathophysiological processes such as epithelial-mesenchymal transition and inhibition of cell contact. Studies have shown that Yap/Taz can affect the progression of vitreoretinal diseases, opening up new prospects for the pathogenesis and clinical treatment of diabetic retinopathy, proliferative vitreoretinopathy, and retinal ischemia-reperfusion injury. Exploring the molecular mechanism of Yap/Taz provides a possible therapeutic target for future research in the treatment of retinal fibrosis diseases such as diabetic retinopathy and proliferative vitreoretinopathy. At the same time, regulating the activity of local Yap/Taz in the retina will also become an effective therapeutic target for damage-repair in retinal ischemia-reperfusion injury. However, Yap inhibitors have potential retinal toxicity and are still in the preclinical development stage. Further research on the mechanism of action and clinical safety of Yap inhibitors will provide new methods for the treatment of retinal diseases.
rough the ultramicroscopic observation on muscle and microcirculation, Group A,where a largeamount of DXM combined with heporin was given svstematically and locally into the femoral artery of the severed limb before replantation, and in Group B only heporin was given, and Group C and D ascontrol.The results showed that if the hormone and heparin were administred in large dosage, it wasadvantageous to reduce the tissues from reperfusion injury during delayed replantation.
【Abstract】ObjectiveTo explore the protective effect of ligustrazine on the ischemia-reperfusion injury of rat liver. MethodsNinety-six healthy SD rats were divided randomly into three groups: sham operation group, ischemiareperfusion group（I/R group) and ischemia plus ligustrazine reperfusion group(therapy group).The plasm ALT,AST and LDH were measured before operation,at thirty minutes,six hours and twentyfour hours after operation. One week survival and liver pathological change of every group were observed, and the hepatocyte apoptosis index was measured simultaneously.ResultsOne week survival of therapy group was higher than that of I/R group (P＜0.05). The plasm ALT,AST and LDH of therapy group and I/R group were higher than those of the sham operation group significantly (P＜0.05), and those of therapy group were lower than those of the I/R group (P＜0.05). Light microscopy indicated that the liver sinusoid and central veins were congested remarkably after operation, the hepatocyte necrosis in I/R group was more severe than that in therapy group, and the hepatocyte apoptosis index of I/R group was higher than that of therapy group (P＜0.05). ConclusionThe protective effect of ligustrazine on ischemia-reperfusion injury of rat liver is obvious.
Objctive To explore the relationship between the expression of Fas/FasL and the apoptosis occurs in retinal ischemia/reperfusion injury of rats , as well as the therapeutic effects of bFGF on the ischemic retina.Methods Th emodels of retinal ischemia/reperfusion injury was made by transient elevating introcular pressure. A total of 28 rats were divided into normal and operation group.The latter were subdivided into 1 hour, 6, 12, 24, 48 and 72 hours after reperfusion group, in which the left eyes of the rats were in the ischemia/reper fusion groups and the right ones were in the treatment groups (bFGF intracameral injection). Apoptosis was assessed by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labelling (TUNEL) method, and the expression of Fas and Fas ligand was studied by strept avidin-biotin complex （SABC）immunohistochemistry. Results No positive cells were observed in the normal rats′retinae, but there was a significant number of TUNEL positive cells in 6-24 hours after transient ischemia followed by a decrease at the 48th hour. The number of TUNEL positive cells reached a maximum at the 24th hour after ischemia. The expression of Fas gradually increased as early as when it was at the 6th hour, reached a peak at the 24th hour, and then decreased at the 48th hour. Similarly, the expression of Fas ligand was at peak in 24-48 hours in GCL and INL of retina. Conclusions Retinal ischemia-reperfusion after transient elevated IOP induced apoptosis of cells in the retina. Fas/FasL may play an important role in the early events of the apoptotic pathways. bFGF can rescue RGCs from retinal ischemia/reperfusion injury through downregulation of the expression of Fas/FasL and may represent an important mechanism for therapeutic neuroprotection. (Chin J Ocul Fundus Dis，2003，19：160-163)
Objective To study the protective effects of pre-storing glycogen on warm ischemia reperfusion injury during partial hepatectomy. Methods Thirty-eight patients were randomly divided into a trial group (n=19) and a control group (n=19). In the trial group, patients were given high concentration glucose intravenously during the 24 hours before the operation. The hepatic lesion was resected after portal triad clamping in the two groups. Liver function of all patients was measured before the operation and the first and fifth days after the operation. Normal hepatic tissue was biopsied to measured hepatic tissue glycogen contents before the operation and the change of superoxide dismutase (SOD) at the point of pre-ischemia, post-ischemia, and reperfusion 2 hour. Bcl-2 mRNA, a well known anti-apoptotic factor, was also detected using quantitative polymerase chain reaction. Results The hepatic tissue glycogen content of the trial group was significantly higher than that of the control group before the operation (Plt;0.01). Liver function of the trial group was significantly better than that of the control group on the first and fifth day after operation (Plt;0.05). There was significant difference in SOD activity between the two groups at the end of hepatic vascular occlusion and at the point of 2-hour reperfusion (Plt;0.05). Furthermore Bcl-2 mRNA expression of the trial group was notably up-regulated at the point of 2-hour reperfusion compared to the control group. Conclusion Pre-store storing glycogen might protect liver ischemia reperfusion injury caused by hepatic vascular occlusion during partial hepatectomy. The potential mechanism might be that pre-storing glycogen enhances Bcl-2 expression.
Exosomes are nanovesicles actively secreted by cells, which selectively encapsulate biologically active molecules such as proteins, RNA, and cytokines. They play an important role in intercellular communication, immune regulation, and maintenance of homeostasis, which can also be used as carriers for targeted drug delivery. Retinal ischemia-reperfusion injury (RIRI) is a retinopathy that seriously threatens human vision. At present, the clinical treatment of these diseases are symptomatic treatments, and some patients have poor efficacy or even blindness. As extracellular vesicles rich in functional proteins and RNAs, exosomes can not only be used as drugs for the treatment of RIRI, but also be used as carriers for drug delivery to play synergistic therapeutic effects. In the future, with the deepening of the research on the molecular structure, contents and biological functions of exosomes, as well as the continuous development of ophthalmic biology and genetic engineering technology, exosomes are expected to exert their great potential as therapeutic drugs and carriers, and become an important means of treating RIRI.