Objective To investigate the protective effects of antitumor necrosis factor-α antibody （TNF-αAb） on lung injury after cardiopulmonary bypass （CPB） and their mechanisms. Methods Forty healthy New Zealand white rabbits，weighting 2.0-2.5 kg，male or female，were randomly divided into 4 groups with 10 rabbits in each group. In groupⅠ，the rabbits received CPB and pulmonary arterial perfusion. In group Ⅱ，the rabbits received CPB and pulmonary arterial perfusion with TNF-αAb. In group Ⅲ，the rabbits received CPB only. In group Ⅳ，the rabbits only received sham surgery. Neutrophils count，TNF-α and malondialdehyde （MDA） concentrations of the blood samples from the left and right atrium as well as oxygenation index were examined before and after CPB in the 4 groups. Pathological and ultrastructural changes of the lung tissues were observed under light and electron microscopes. Lung water content，TNF-α mRNA and apoptoticindex of the lung tissues were measured at different time points. Results Compared with group Ⅳ，after CPB，the rabbitsin group Ⅰ to group Ⅲ showed significantly higher blood levels of neutrophils count，TNF-α and MDA（P＜0.05），higherTNF-α mRNA expression，apoptosis index and water content of the lung tissues （P＜0.05），and significantly lower oxyg-enation index （P＜0.05） as well as considerable pathomorphological changes in the lung tissues. Compared with group Ⅱ，after CPB，the rabbits in groups Ⅰ and Ⅲ had significantly higher blood concentrations of TNF-α （5 minutes after aortic declamping，220.43±16.44 pg/ml vs.185.27±11.78 pg/ml，P＜0.05；249.99±14.09 pg/ml vs.185.27±11.78 pg/ml，P＜0.05），significantly higher apoptosis index （at the time of CPB termination，60.7‰±13.09‰ vs. 37.9‰±7.78‰，P＜0.05；59.6‰±7.74‰ vs. 37.9‰±7.78‰，P＜0.05），significantly higher blood levels of neutrophils count and MDA （P＜0.05），significantly higher TNF-α mRNA expression and water content of the lung tissues （P＜0.05），and significantly loweroxygenation index （P＜0.05） as well as considerable pathomorphological changes in the lung tissues. Compared with groupⅠ，rabbits in group Ⅲ had significantly higher above parameters （P＜0.05） but lower oxygenation index （P＜0.05） only at 30 minutes after the start of CPB. Conclusion Pulmonary artery perfusion with TNF-αAb can significantly attenuate inflammatory lung injury and apoptosis of the lung tissues during CPB.
Objective To investigate the preventive and therapeutic effects and the mechanisms of pyrrol idine dithiocarbamate (PDTC) on the atrophy of denervated skeletal muscle. Methods Thirty adult Wistar rats of either gender, weighing (200 ± 10) g were randomly divided into 3 groups: group A (n=6, control group), group B (n=12, denervation group), and group C (n=12, PDTC treatment group). The sciatic nerves of the rats were only exposed without cutting off in group A, and the rats were made denervated gastrocnemius models in groups B and C. PDTC of 100 mg/(kg•d) was injected peritoneally in group C and an intraperitoneal injection of the same amount normal sal ine was given in group B. After 14 and 28 days, the gastrocnemius was harvested to measure the ratio of muscle wet weight; the levels of nuclear factor of κB (NF-κB)p65 protein and the opening of the mitochondrial permeabil ity transition pore (MPTP) in the gastrocnemius were detectedrespectively by Western blot and laser confocal scanning microscope; and the apoptotic cells in atrophic muscle were measured with TUNEL. Results The ratio of muscle wet weight in group A was 1.039 ± 0.115, and it significantly decreased in groups B and C (P lt; 0.05); after 14 and 28 days of operation, the ratio of muscle wet weight in group C significantly increased when compared with those in group B (P lt; 0.05). The expression of NF-κB p65 protein in group A was 0.224 ± 0.041; the expressions of NF-κB p65 in groups B and C significantly increased when compared with that in group A (P lt; 0.05); however, the expression of NF-κB p65 in group C was significantly lower than that in group B (P lt; 0.05). The MPTP fluorescence intensity in group A was 31.582 ± 1.754; the MPTP fluorescence intensity was significantly lower in groups B and C than in group A (P lt; 0.05), and the MPTP fluorescence intensity in group C was significantly higher than that in group B (P lt; 0.05). The rate of apoptosis in group A was 4.542% ± 0.722%; after 14 and 28 days of operation, the rates of apoptosis significantly increased when compared groups B and C with group A, and signiticantly decreased when compared group C with group B (P lt; 0.05). Conclusion PDTC can retard denervated skeletal muscle atrophy, and the effect may have a relationship with its inhibition on NF-κB, the opening of the MPTP, and the ratio of apoptosis.
Objective To investigate the influence of vascular endothelial growth factor (VEGF) antagonist bevacizumab on the growth of human choroidal melanoma (CM) OCM-1 cell xenografts in nude mice, and to explore the probable mechanism.Methods OCM-1 cells were subcutaneously implanted on 18 nude mice to establish ectopic model of human CM. The nude mice with the tumor of 5 mm in diameter were randomly divided into three groups: untreated group (group A), normal saline （NS） group (group B), drug treated group (group C). Bevacizumab was intraperitoneally injected for 14 consecutive days in group C, and the same volume of NS was used at a same way in group B. The volume and weight of implanted tumor as well as inhibitory rates of drug on tumor were calculated, ki67 and survivin proteins were measured with immunohistochemistry, and the mRNA expression of VEGF and survivin were assessed by RT-PCR.Results The volume and weight of tumor was (598.86plusmn;321.81) mm3, (0.66plusmn;0.15) g; (1 715.15plusmn;278.16) mm3, (1.54plusmn;0.39) g and (1 750.23plusmn;206.36) mm3, (1.54plusmn;0.31) g in groups C, A and B, respectively. There were significant differences between group C and A (F=34.53, P=0.00) and group C and group B (F=8.69, P=0.01). The inhibitory rate of these three groups were 57.14%, 5.31%, 6.25%, respectively, and the proliferation index (PI) of ki67 in these three groups were (51.85plusmn;1.32)%, (46.30plusmn;1.39)%, (27.90plusmn;0.90)%, respectively, there were significant differences in ki67 PI between C group and A or B group (H=15.17, P=0.00). The expression of survivin mRNA was (0.49plusmn;0.02), (0.82plusmn;0.05) and (0.61plusmn;0.05) in groupss C, A and B, respectively, there were significant differences between C group and A or B group (F=15.17, P＜0.05) . The expression of VEGF mRNA was (0.32plusmn;0.08), (0.73plusmn;0.07), (0.80plusmn;0.04) in groups C, A and B, significant difference was found between group C and A or B group (F=12.05，P＜0.05). Conclusion Bevacizumab can inhibit the growth of human CM in nude mice probably by inhibiting the activity of VEGF and downregulating survivin expression of the tumor as well as inhibiting the growth of the tumor.
Objective To observe expression of Caspase-3 and apoptosis around the prosthesis and explore the relationship of the expression and the apoptosis with the periimplant osteolysis. Methods From April 2001 to August 2006, 16 patients (10 males, 6 females) underwent the revision total hip arthroplasty surgery, who had the primary total hip arthroplasty at the ages of 45-67 years and had the revision total hip arthroplasty at the ages of 55-78 years, with the implantation duration of 7-13 years. According to their preoperative X-ray films andthe findings during the operation, the patients were divided into two groups: theloose/osteolytic group (n=8) and the loose/non-osteolytic group (n=8). The interface tissues were obtained from the peri-implant region in the patients. The synovial samples were taken from another 6 patients (2 males, 4 females; age, 54-68years; illness course, 9-15 years), who underwent the primary total hip arthroplasty for osteoarthritis. These 6 patients were used as controls. The tissues were prepared for the immunohistochemical assays to determine the expression of Caspase-3. The TUNEL assays were performed to quantify the apoptotic cells. The quantitative analysis on the positive cells and the correlation with the presence of the particulate wear debris and the severity of osteolysis were also performed. Results The level of the expression for Caspase-3 and the apoptosis index inthe loose/osteolytic group were significantly increased when compared with those in the loose/non-osteolytic group and the control group (P＜0.01). The polyethylene particles were surrounded by more positive cells than the metal particles. The positive cells were present at a higher level in the tissue sections where the high-wear status was present when compared with the areas where the low-wear status was present (P＜0.05). Conclusion There is a statistical correlation of the Caspase-3 expression to the apoptosis index and to the presence of the particulate wear debris and the severity of osteolysis, which may be one of the key points for the bone reconstruction inhibition and the bone resorption at the boneimplant interface under the stimulation of the wear debris. The apoptosis is involved in the pathogenesis of the aseptic loosening, which is closely related to the signal transportation of Caspase-3.
Objective To investigate the mechanism of the resistance of pancreatic cancer cells to tumor necrosis factor related apoptosis inducing ligand (TRAIL)mediated apoptosis. MethodsThe expression of TRAIL receptor-4 (TRAIL-R4) in normal pancreas tissue and pancreatic cancer was analyzed by using Northern blotting, Western blotting and immunohistochemistry.ResultsTRAIL-R4 mRNA and protein were expressed at moderate to high levels in human pancreatic cancer, but demonstrated weak to negative in the normal pancreas. Moreover, pancreatic cancer cells showed b TRAIL-R4 immunostaining throughout the tumor mass. Conclusion TRAIL-R4 levels are significantly different in pancreatic cancer in comparison to the normal pancreas. These findings give new insights into the resistance mechanisms of pancreatic cancer cells towards TRAILmediated apoptosis.
Objective To investigate the effect of berbamine (BBM) on the proliferation and apoptosis of retinoblastoma (RB) HXO-RB44 cells and its possible mechanism in vitro.Methods RB cells in logarithmic growth phase were divided into BBM treated group and control group. RB cells in BBM treated group were cultured with different concentrations of BBM (2,4,8,16 and 32 mg/L) for 24,48 and 72 hours, respectively. The proliferation was assayed by methyl Thiazolyl tetrazolium (MTT). RB cells were cultured with different concentrations of BBM (4,8 and 16 mg/L) for 24 hours. The early apoptotic rates were detected by flow cytometry; the expression of bcl-2 and Bax were measured by enzyme-linked immunosorbent assay (ELISA) and the activity of Caspase-3 was detected by colorimetric assay.Results BBM could obviously inhibit the proliferation of RB cells in a time and dose dependent manner (24 hours: F=70.547,P＜0.01; 48 hours: F=603.438,P＜0.01; 72 hours: F=577.521,P＜0.01). The IC50 value at 24,48 and 72 hours were 25.26, 10.94 and 6.25 mg/L, respectively. Necrosis rates of control group and BBM treated group were (1.25plusmn;0.45)%, (4.10plusmn;2.95)%, (4.39plusmn;0.21)% and (10.54plusmn;4.38)% respectively; the difference between two groups was statistically significant (F=6.527,P＜0.05). Apoptotic and necrosis rates in advanced stage of control group and BBM treated group were (2.13plusmn;0.71)%, (5.45plusmn;2.31)%, (9.86plusmn;3.18)% and (11.10plusmn;1.70)%, respectively. The difference between two groups was statistically significant (F=10.845,P＜0.05). Early apoptotic rates of control group and BBM treated group were (0.51plusmn;0.26)%, (2.68plusmn;0.35)%, (5.97plusmn;0.50)% and (11.22plusmn;1.17)%, respectively. The difference between two groups was statistically significant (F=144.976,P＜0.01). In addition, BBM dose-dependently reduced bcl-2 level and increased Bax expression, causing the reduction of the bcl-2/Bax protein ratio as well as increased the Caspase-3 activity in RB cells remarkably (bcl-2: F=835.726,P＜0.01; bax: F=111.963, P＜0.01;Caspase-3:F=298.058,P＜0.01).Conclusions BBM can inhibit the proliferation and induce apoptosis or necrosis of RB cells in vitro, down regulating the expression of bcl-2, up regulating the expression of Bax. Along with increased Caspase-3 activity these may be the apoptotic mechanisms.
Objective To investigate inhibited effects of melatonin (MLT) on proliferative activity of retinoblastoma cell line HXORB44 and its related mechanism. Methods HXO-RB44 cells were treated by MLT of different concentration (10-10, 10-9, 10-8, 10-7 mmol/L. Cell counting and tetrazolium dyereduction assay (MTT) were used to determine the effect of MLT on the survival and proliferation of HXO-RB44 cells. Apoptotic nuclei were further analyzed by HoechstPI fluorescence staining. Flow cytometry was used to measure the fluorescent intensity of ROS, cell cycle distribution and apoptosis. Results 10 -6 mmol/L (or exceed) of MLT could inhibit the proliferation of HXO-RB44cells in vitro while 10-7 mmol/L (or below) of MLT couldn't. With the increase of MLT concentration from 10-10 mmol/L to 10-7 mmol/L, HXO-RB44 cells gradually increased the expression of ROS. Hoechst staining showed that 4, 8, 12 and 24 hours after the incubation with MLT, the nuclear pyknosis and nuclear fragmentation increased in HXORB44 cells. The extent of apoptosis was proportional to the concentrations of MLT. Flow cytometry revealed that with the increasing of MLT concentration, G0/G1 and G2/M phase cells increased, S phase cells decreased. The apoptotic rate was also increased. Conclusion 10 -6 M of MLT could inhibit the proliferation of HXO-RB44 cells. This effect may relate to the increased ROS expression, cell cycle arrest at G0/G1 phase and apoptosis of HXO-RB44 cells.
Objective To explore the expression and significance of hypoxia-inducible factor 1α (HIF-1α) in endplate chondrocytes, and to study the relations between HIF-1α expression and endplate chondrocytes apoptosis. Methods Eight Sprague Dawley rats were selected to obtain the L1-5 intervertebral disc endplate; the endplate chondrocytes were isolated by enzyme digestion method, and the endplate chondrocytes at passage 3 were cultured under 20% O2 condition (group A), and under 0.5% O2 condition (group B). Cell morphology was observed by inverted phase contrast microscope and cell apoptosis was detected using flow cytometry after cultured for 24 hours; the mRNA expression of HIF-1α was detected by real-time fluorescent quantitative PCR, the protein expressions of HIF-1α, Bax, and Bcl-2 by Western blot. Gene clone technology to design and synthesize two siRNAs based on the sequence of HIF-1α mRNA. HIF-1α specific RNAi sequence compound was constructed and transfected into cells. The transfected endplate chondrocytes at passage 3 were cultured under 0.5% O2 condition in group C and group D (HIF-1α gene was silenced). After cultured for 24 hours, cells were observed via immunofluorescence staining of HIF-1α, and cell apoptosis was detected using flow cytometry. Meanwhile, the mRNA expressions of HIF-1α, collagen type II (COL II), Aggrecan, and SOX9 were detected by real-time fluorescent quantitative PCR, and the protein expressions of HIF-1α, Bax, and Bcl-2 by Western blot. Results At 24 hours after culture, small amount of vacuoles necrotic cells could be observed in group A and group B; there was no significant difference in apoptosis rate between groups A and B (t=1.026,P=0.471), and HIF-1α mRNA and protein expressions in group B were significantly higher than those in group A (t=22.672,P=0.015;t=18.396,P=0.013), but, there was no significant difference in protein expressions of Bax and Bcl-2 between groups A and B (t=0.594,P=0.781;t=1.251,P=0.342). The number of vacuolar necrosis cells in group D was significantly higher than that in group C, and HIF-1α positive cells were observed in group D. The apoptosis rate of group D was significantly higher than that of group C (t=27.143,P=0.002). The mRNA expressions of HIF-1α, COL II, Aggrecan, and SOX9 in group D were significantly lower than those in group C (t=21.097,P=0.015;t=34.829,P=0.002;t=18.673,P=0.022;t=31.949,P=0.007). The protein expressions of HIF-1α and Bcl-2 in group D were significantly lower than those in group C (t=37.648,P=0.006;t=16.729,P=0.036), but the protein expression of Bax in group D was significantly higher than that in group C (t=25.583,P=0.011). Conclusion HIF-1α mRNA expression is up-regulated under hypoxia condition, which will increase the hypoxia tolerance of endplate chondrocytes. Cell apoptosis is suppressed by the activation of HIF-1α in endplate chondrocytes under hypoxia condition.
目的:探讨白藜芦醇对人脑胶质瘤U251细胞的凋亡相关因子caspase-3的作用。方法:应用RT-PCR方法和Western-blot分别检测凋亡因子caspase-3的RNA和蛋白水平的表达。结果:白藜芦醇能明显促进U251细胞的凋亡相关因子caspase-3的表达,存在剂量依赖与时间依赖性。结论:白藜芦醇能通过caspase－3途径诱导U251细胞的凋亡。