Objective To investigate the relationship of the expression between heat shock protein (HSP) 70 and 90, and Survivin and its effects on the proliferative activity in retinoblastoma (RB) cells. Methods Expression of Survivin, HSP70 and 90, and Ki-67 in conventional paraffin samples from 43 patients with RB and 6 healthy people was detected by streptavidin-biotin peroxidase (SP) immunohistochemical method. Ki67 labeling index was used to evaluate the proliferative activity in RB. Results In 43 cases of RB, positive expression of HSP70 and 90 and Survivin was found in 28 (65.12%), 37 (86.05%) and 27 (62.79%) cases, respectively. None of the 6 normal retinal tissue expressed HSP70, HSP90 or Survivin. Positive expression of Survivin was more frequent in positive expressions of HSP90 than that in negative expressions of HSP90 (P<0.05). Ki67 labeling index was higher in positive expressions of HSP90 and positive expressions of Survivin than that in their negative expressions respectively (P<0.05). Meanwhile, higher Ki67 labeling index was found in positive HSP90Survivin expressions than that in negative HSP90Survivin expressions and those cases where only HSP90 or Survivin was found (P<0.05). Expression of HSP70 did not correlate with that of Survivin, nor had any significant effect on Ki67 labeling index (P>0.05). Expression of HSPs and Survivin and Ki67 labeling index did not correlate with histological types (P>0.05). Conclusion Expression of HSP90 correlates with that of Survivin in RB. Co-existence of Survivin and HSP90 probably plays an important role in the genesis of RB.
Objective To investigate the expression of induced heat shock protein (HSP) 70 in ratprime;s retinal neurons (RNs) and Muuml;ller cells, and evaluate the protective effect of HSP 70 on RNs injured with glucose deprivation and glutamate. Methods Ratprime;s RNs and Muuml;ller cells cultured in vitro were treated with heat shock (42℃ for 1 hour), and duration of the expression of HSP70 was detected by immunocytochemical techniques. Viability of the cells was measured by methyl thiazolyl tetrazolium (MTT) chromatometry after incitant toxic injury with glucose deprivation (0.56 mmol/L glucose for 6 hours) and glutamate (100 mu;mol/L for 6 hours). Simultaneously, the expression was interdicted by HSP70. Results Hypereffective expression of HSP70 was found in cultured RNs and Muuml;ller cells after heat shock. The viability of RNs pretreated by heat shock after injured with glucose deprivation and glutamate significantly increased which could be interdicted by HSP70 antibody. Conclusion Hypereffective expression of HSP 70 may be induced by heat shock, which enhances the ability of tolerance of RNs to the incitant toxic injury by glucose deprivation and exitotoxicity. (Chin J Ocul Fundus Dis, 2005,21:110-113)
Objective To observe the effects of basic fibroblast growth factor (bFGF) on the expression of heat shock protein 70 (HSP70) in ratrs retina after iscbemia/reperfusion injury.Methods The rat model of experimental retinal ischemia/reperfusion injury was made by increasing the intraocular pressure. Tweenty-four Wistar rats were divided into normal (3 rats) and operation group (21 rats) randomly. The latter group was subdivided into group 0 hour, 4, 8, 12, 24, 48 and 72 hours after reperfusion, in which the left eyes of the rats were in the ischemia/reperfusion groups and the right ones were in the treatment groups (bFGF 2 t~g intracameral injection). The expression of HSP70 was observed by strept avidin-biotin complex (SABC) immunohistochemistry. Results No HSP70 positive cells were found in normal group; a few of HSP70 positive cells were found 0 hour after reperfusion [20.8±4. 5) cells/mm2], and increased gradually until reached the peak 24 hours later [(111.2±4.4) cells/mm2] and then decreased gradually. Few HSP70 positive cells were found 72 hours after reperfusion. The amount of HSP70 positive cells increased in treatment group at all time courses, and the peak time was earlier and longer than that in ischemia group. HSP70 positive cells distributed extensively in retinal ganglion cell layer and inner nucleous layer. The difference of the amount of HSP70 positive cells between the two groups was significant (Plt;0.05) 8, 12, 24, 48 and 72 hours after reperfusion.Conclusion bFGF can enhance the expression of HSP70 in rat’s retina after retinal ischemia/reperfusion injury.(Chin J Ocul Fundus Dis,2004,20:37-39)
ObjectiveTo investigate the effect of heat shock protein B8 (HspB8) downregulation on retinal ganglion cell (RGC) and retinal function in the mice model of optic nerve injury (ONC).MethodsAdeno-Associated Virus (AAV) 2 AAV2-shHspB8-GFP was constructed to knockdown HspB8. 66 adult male C57/BL6 mice were randomly divided into the control group, the ONC group, the AAV2-shHspB8 group, the ONC+AAV2-shHspB8 group, and the ONC+AAV2- GFP group. There were 10, 20, 16, 10 and 10 mice respectively, and both eyes were used as experimental eyes. Western blot was used to evaluate the expression of HspB8 on day 3 and 7 after ONC. By GFP immunofluorescence staining, the efficacy of AAV2-shHspB8-GFP transfer was accessed. Moreover, it was possible to identify functional and RGC survival differences between groups by optomotor response (OMR), dark adapted full-field flash electroretinogram (ff-ERG), oscillatory potentials (OPs), photopic negative response (PhNR) and retinal flat-mount RGC counting 5 days after ONC. Comparisons between two groups were made using Mann-Whitney U test, unpaired t-test, unpaired t-test with Welch’s correction, one-way ANOVA, and Bonferroni t test.ResultsCompared with the control group, the expression of HSPB8 protein in the retina of mice in ONC3 group was significantly increased, and the difference was statistically significant (F=43.63, P<0.01). Compared with the control group, the ONC group showed obviously lower visual acuity (P<0.01), lower a-wave, b-wave, OPs, PhNR amplitude, longer b-wave latency (P<0.05), and the survival rates of RGC in ONC3 group, ONC5 group and ONC7 group decreased in a time-dependent manner(F=384.90, P<0.01). Transfection of AAV2 efficiency was highest on 4 weeks after IVT. Besides, there was no significant differences between the control group and the AAV2-shHspB8 group on visual acuity, ff-ERG, OPs, PhNR and RGC survival (P>0.05). In comparison of the control group, we found that RGC survival of the ONC5+AAV2-shHspB8 group was significantly elevated (F=10.62, P<0.01).ConclusionsExpression of HspB8 on the retina can be induced by ONC. The investigation of RGC counting, visual acuity, and ff-ERG revealed that optic nerve injury destructed functionality of mice retina and resulted to RGC death ultimately. The Most crucial finding of this research is that HspB8 knockdown had a neuroprotective effect in RGC after ONC.