Objective To investigate the effects of genistein with different concentration on proliferation and apoptosis of cultured human retinal pigment epithelial (RPE) cells in vitro. Methods The effect of genistein with the concentration of 5，10，25，50，75，and 100 mg·L-1on the proliferation of cultured RPE was examined by tetrazolium salt (MTT) assay and AgNORs staining. The cell apoptosis was detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine 5-triphosphate nick-end labeling (TUNEL) methods, in the mean time, the morphologic changes of cell apoptosis were observed by light microscopy and transmission electronic microscopy, the results of which were compared with the normal RPE cells. Results Genistein with the concentration of 25, 50, 75, and 100 mg·L-1had a dose-dependent and time-dependent antiproliferative effects on RPE cells with the inhibitory rate of 12.0%-64.6% (P＜0.05). The results of AgNORs staining showed that the number of AgNORs in the nucleolus decreased when treated by genistein. In TUNEL staining, the median of percent of apoptotic RPE cells was 7.6%, 9.8%, 13.7% when treated with 50 mg·L-1genistein, 10.3%, 16.4%, 23.4% when treated with 75 mg·L-1genistein, and 15.4%, 21.2%, 35.8% when treated with 100 m g·L-1genistein respectively for 24, 48, and 72 hours. After the treatme nt with 50 mg·L-1genistein for 48 hours, the apoptosis in the nucleolus of RPE cells was found. Conclusions Genistein with different concentrations has a dose-dependent and time-dependent antiproliferative effect on RPE cells. Genistein can induce the apoptosis of RPE cells when it reaches a certain extent of concentration. (Chin J Ocul Fundus Dis，2004，20：241-244)
Objective To observe the histological changes and apoptosis of retinal cells in pigmented rabbits treated by transpupillary thermotherapy (TTT) with different laser power. Methods Fourteen pigmented rabbits (28 eyes) were divided averagely into seven groups（control group, 50, 70, 90, 110, 130, and 150 mW group）according to different laser power of TTT. Light microscopy was performed to observe the histological changes, and TDT-mediated biotin-dUTP nick-end labeling (TUNEL) technique and flow cytometry (FCM) examination were used to detect the apoptotic cells 24 and 48 hours after photocoagulation, respectively. Results The color of retinal burn speckles changed from offwhite to white and super white with the diameter enlarged gradually as the laser power of TTT increased. The results of light microscopy revealed that compared with the control group, the retinal tissue did not change much in 50-70 mW group; in 90-130 mW group, the retinal structure was integrated, but the cone and rod cells became swollen and condensed nuclei and cytoplasmic vacuolization were seen in the inner nuclear layer. The difference of retinal structure in 50-130 mW group 24 and 48 hours after photocoagulation and control group was not significant. In 150 mW group, tumefaction and degeneration were observed in each layer of retina and the inner and outer segments of photoreceptor cells lost 24 hours after photocoagulation, and obvious necrosis and cell loss of retinal tissues were detected hours after photocoagulation. The results of TUNEL examination indicated that positive cells were found in outer nuclear layer in each photocoagulation group which increased as the laser power of TTT was enhanced; the apoptosis gradually involved the inner nuclear layer and ganglion cell layer. The results of flow cytometry (FCM) examination showed the peak of apoptotic cells in each photocoagulation group 24 hours after photocoagulation. Conclusion Under certain subthreshold photocoagulation (50-70 mW), retinal tissue of rabbits does not change much but apoptosis of photoreceptor cells increase significantly. As the laser power of TTT increases, the retinal tissues become swollen, degenerated and even necrotic; cellular apoptosis gradually involves the inner nuclear layer and ganglion cell layer. (Chin J Ocul Fundus Dis, 2006, 22:249-252)
ObjectiveTo evaluate the protective effect of estrogen on survival of retinal ganglion cells (RGCs) after transient retinal ischemia-reperfusion (RIR) in rats.MethodsRIR was induced in 60 ovariectomized adult rats (OVX) by increasing intraocular pressure via an intracameral catheter. All of the rats were divided into two groups randomly: in experimental group, the rats underwent a subcutaneous injection with 17β-estrodiol（100 μg/kg） 2 hours before retinal ischemia; and in the control group, saline water was injected correspondingly. The number of RGCs and the thickness of the inner retinal layers were mesured by HE staining method before and 12, 24, 48, and 72 hours after reperfusion. TdT-mediated biotin-dUTP nick end labelling (TUNEL) staining technique was used to examine the apoptosis of RGCs.ResultsTwenty-four and 48 hours after reperfusion, the number of apoptotic cells in experimental group was obvious lower than that in the control group(Plt;0.05), and the number of RGCs in experimental group was higher than that in the control group(Plt;0.05).ConclusionEstrogen can protect retinal neurons from transient RIR in ovariectomized rats.(Chin J Ocul Fundus Dis, 2005,21:177-179)
Objective To summarize the research progress of microRNA in acute pancreatitis. Methods By reading the domestic and international literatures published in recent years, to summarize the research progress of microRNA in acute pancreatitis. Results In recent years, researches had found that microRNA could be used as a biomarker for acute pancreatitis to predict and determine the occurrence, development, and complications of acute pancreatitis. MicroRNA could regulate the programmed cell death of acute pancreatitis, and played an important role in the development of inflammation and complications, it also could be used as a therapeutic target for acute pancreatitis. Conclusions MicroRNA plays an important role in the development of acute pancreatitis. Researching the mechanism of microRNA in acute pancreatitis is helpful for the treatment and prevention of acute pancreatitis.
Objective To observe the effect of visible light on apoptosis of cultured human retinal pigment epithelium (RPE) cells. Methods Being the light source,500lx,(2 000±500)lx and (3 400±200)lx cold white light were used. The duration of exposure was 0,6,12 and 24 hours respectively. Apoptosis was detected by terminal deoxynucleotidyl transferase mediated dUTP nick end labelling, Annexin V-flunorescein isothiocyanate/Propidium iodium labelling and flow cytometry. Results Apoptosis and necrosis were found in cultured human RPE cells which were exposed to visible light.(1)A significant increase in apoptotic and necrotic percentages was consistent with a higher light intensity.(2)Apoptosis was the main response to shorter (6 h and 12 h) exposure duration,while necrosis was more pronounced correlated to the prolongation of post-exposure culture (P＜0.05),and the longer the post-exposure period was, the more apoptotic necrosis were seen.Thirty-six hours after exposure the necrotic percentages were more pronounced (P＜0.01). Conclusions Visible light (＞500 lx) increases the proportion of apoptosis and necrosis of human RPE cells in vitro.The extent is related to exposure intensity and duration. It demonstrates that the lower intensity and the shorter duration of exposure to light are, the more pronounced apoptotic percentages are observed,otherwise necrosis. (Chin J Ocul Fundus Dis, 2002, 18: 227-230)
Objective To investigate the correlation of ascorbic acid distribution and retinal susceptibility to iron toxicity of the retina.Methods Autoclaved iron particles of 5 mg and 15 mg were implanted into the vitreous cavities of 32 Spragu-Dawley (SD) rats and 9 rabbits, respectively. The retinal sections of rats and rabbits were examined after hemotoxylin-eosin (HE) staining. Apoptos is of rabbits′retinal neurons was investigated by TdT-mediated dUTP-biotin nick-end labeling (TUNEL). Chinoy′s method was used to observe the distribution of as corbic acid in the retinae of the 2 kinds of animals.Results In rats, histological and structural densification was observed only in the photoreceptor cells after implantation of the iron particles. In rabbits, however, histological and structural destruction as well as TUNEL-positive nuclei were observed in all neuronal layers of the retina 3 days after the implantation of the iron particles. Silver granules reduced by ascorbic acid from silver nitrate were observed only in the outer nuclear layer in normal rats retinae, while they were observed evenly throu ghout all layers of rabbits′retinae. Conclusions The suscept ibility of retina to iron toxicity is correlated to the distribution of ascorbic acid in retina. (Chin J Ocul Fundus Dis，2003，19：269-332)
ObjectiveTo understand the current progress of programmed cell death in the pathogenesis of acute pancreatitis, and to provide reference for the pathogenesis and treatment of acute pancreatitis.MethodThe research progress of acute pancreatitis and programmed cell death in recent years was reviewed by reading relevant literatures at home and abroad in recent years.ResultsProgrammed cell death was defined as controlled cell death performed by intracellular procedures, including apoptosis, autophagy, programmed necrosis, and coronation. The pattern of death of pancreatic acinar cells mainly includes apoptosis and programmed necrosis. Although the pathogenesis of acute pancreatitis had not yet been fully clarified, it was known that through the study of programmed cell death, it could help us to understand the pathogenesis and pathogenesis of acute pancreatitis and provide more effective treatment methods.ConclusionsProgrammed cell death is very important for acute pancreatitis. The mechanism of programmed cell death in acute pancreatitis is necessary for the treatment and prevention of it.
Objective To investigate the correlation of expression of Fas/Fas ligand (FasL) and apoptosis in retinoblastoma (RB)． Methods The expression and distribution of Fas/FasL were detected by using immunohistochemical staining in 32 cases of RB． Light microsc opy (32 cases), electron microscopy (4 cases) and TdT mediated biotin-d UTP nick-end labeling (TUNEL) (12 cases) were used to study apoptosis in RB． Results Apoptotic RB cells mostly located at RB regress area． Chromatin margination and apoptotic bodies were found in RB． TUNEL posi tive labeling cells especially located in tumor regress area． Positive immunola beling for Fas and FasL was found in all RB specimens． There was a highly signi ficant and positive correlation between the expression of Fas/FasL and apoptotic indices (AI) (Plt;0.01 or 0.001)． Conclusion The results suggest that apoptotic cell death is prevalent in RB and it may be one type of the most dominant cell death． Fas system may play an important role in oncogenesis and progression of RB, and the up-regulation of Fas system expression might induce RB cell apoptosis． (Chin J Ocul Fundus Dis, 2001,17:21-23)