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 cell cycle as a new tool to evaluate the biocompatibility of biomaterials.Methods The cell cycle and the expression of related genes were analyzed by the methods of immunocytochemistry, protein blotting, RT PCR and flow cytometry. Results The physical properteis, chemical properties and topological properities of biomaterials could not only influence cell cycle of the cells attached onto biomaterials but also affect the expression of related genes of target cells. Conclusion As an important extension of routine proliferation epxeriments, the study of cell cycle control will be great help for us to to study the cell group as an organic society. It revealed the balance between cell proliferation, cell differentiation and apotosis. It is suggested that the study of cell cycle control will play a key role in the research of tissue engineering.
【 Abstract 】 Objective To probe into the role of inositol 1, 4, 5-trisphosphate (IP3) and bax gene expression in apoptosis of HepG2 cells induced by genistein (Gen). Methods HepG2 cells were treated with different concentrations including 20, 40, 60 and 80 μ mol/L Gen as HepG2 cells cultured with 0 μmol/L Gen for 72 h was control; HepG2 cells were treated with 60 μmol/L Gen for 6, 12, 24, 48 and 72 h as HepG2 cells treated with 60 μmol/L Gen for 0 h was control. IP3 content, bax mRNA expression and apoptosis rate were assayed by IP3- [ 3H ] Birtrak assay, RT-PCR and flow cytometry, respectively. ResultsHepG2 cells incubated with each concentration of Gen for 72 h , IP3 content was lower than that of control 〔 (17.7 ± 1.3), (11.2 ± 0.9), (4.9 ± 0.5), (4.8 ± 0.3) pmol/106 cells vs (29.4 ± 0.5) pmol/106 cells 〕 , P < 0.01 ; bax mRNA expression (RI which was the gray degree multiply area of bax/the gray degree multiply area of β -actin) was higher than that of control (0.26 ± 0.02, 0.33 ± 0.05, 0.35 ± 0.06, 0.38 ± 0.05 vs 0.09 ± 0.01), P < 0.01 ; The apoptosis rate was higher than that of control 〔 (10.1 ± 0.9)%, (18.7 ± 1.6)%, (28.7 ± 2.5)%, (27.9 ± 2.0)% vs (2.6 ± 0.1)% 〕 , P < 0.01. HepG2 cells were incubated with 60 μ mol/L Gen for 6, 12, 24, 48 and 72 h , IP3 content was lower than that of control 〔 (22.6 ± 0.9), (12.0 ± 1.4), (7.5 ± 0.8), (5.6 ± 0.5), (4.3 ± 0.6) pmol/106 cells vs (29.2 ± 0.6) pmol/106 cells 〕 , P < 0.01 ; bax mRNA expression was higher than that of control incubated with 60 μ mol/L Gen for above 12 h (0.25 ± 0.06, 0.29 ± 0.02, 0.30 ± 0.02, 0.35 ± 0.04 vs 0.09 ± 0.01), P < 0.01 ; The apoptosis rate in groups incubated with 60 μ mol/L Gen for 24, 48 and 72 h was significantly higher than that in control 〔 (7.4 ± 0.5)%, (20.5 ± 2.0)%, (30.7 ± 1.6)% vs (2.6 ± 0.1)% 〕 , P < 0.01. ConclusionGen induces apoptosis of HepG2 cells by reducing IP3 production and increasing bax gene expression.
Objective To detect the cell density, apoptotic rate, and the expressions of BNIP3 in nucleus pulposus of degenerative intervertebral disc of rabbits, so as to further understand the mechanism of intervertebral disc degeneration. Methods Thirty male New Zealand white rabbits, aging 3 months and weighing (2.3 ± 0.2) kg, were divided into sham operation group (control group, n=10) and intervertebral disc degeneration model group (experimental group, n=20). Interbertebral disc degeneration models were establ ished by puncture of L3,4, L4,5, and L5,6 intervertebral discs in the experimental group; intervertebral discs were exposed only and then sutured in the control group. The degree of intervertebral disc degeneration was evaluated according to Pfirrmann classification by MRI at 4 and 8 weeks after establ ishing models. Apototic cells were determined by TUNEL and histological methods, and the immunohistochemical staining was performed to detect the expressions of BNIP3 in nucleus pulposus of intervertebral disc. Results MRI examination showed that the signal intensity decreased gradually at 4 and 8 weeks in the experimental group. There wassignificant difference in the degree of intervertebral disc degeneration between at 4 weeks and at 8 weeks in the experimental group (P lt; 0.05). The histological observation and TUNEL test showed that high density of nucleus pulposus cells and only a few apoptotic cells were observed in the control group; at 4 and 8 weeks, the density of nucleus pulposus cells decreased gradually with more apoptotic cells in the experimental group. There were significant differences in the nucleus pulposus cell density and positive rate of TUNEL staining between 2 groups, and between at 4 weeks and at 8 weeks in the experimental group (P lt; 0.05). The expression of BNIP3 of nucleus pulposus was negative in the control group; however, in the experimental group, the positive expression rates of BNIP3 of nucleus pulposus (the gray values) were 13.45% ± 1.16% and 32.00% ± 1.82% (194.32 ± 4.65 and 117.54 ± 2.11) at 4 and 8 weeks respectively, showing significant differences (P lt; 0.05). Conclusion The decrease of cell density in nucleus pulposus is involved in the development of intervertebral disc degeneration. Cell apoptosis is one of reasons in the decrease of nucleus pulposus cell; BNIP3 is involved in nucleus pulposus cell apoptosis in the degenerative intervertebral disc.
ObjectiveTo observe the influence of heat shock protein 27 (HSP27) sensibilization to retinal ganglion cells (RGC) apoptosis of rats. MethodsThirty-five female Wistar rats were randomly divided into HSP27 sensibilization group (15 rats), borate buffer solution (BBS) control group (15 rats) and normal group (5 rats). The rats in HSP27 sensibilization group were received hypodermic injection in rear limb with 100 μg HSP27 and complete freund adjuvant, intraperitoneal injection with 1 μg pertussis toxin. The BBS control group received the same volume of BBS at the same site. The normal group received no intervention. The intraocular pressure was measured 3 days before injection and 1, 2, 4, 6, 8 weeks after injection. Four, 6 and 8 weeks after injection, the retinal frozen sections was made to observe RGC apoptosis by terminal-deoxynucleoitidyl transferase mediated nick end labeling. The anti-HSP27 level in serum and cerebrospinal fluid were detected by enzyme linked immunosorbent assay. ResultsThere was no obvious change of intraocular pressure in rats in 3 groups before injection (P>0.05). RGC apoptosis was observed in HSP27 sensibilization group 4 weeks after injection, and increased significantly at 6 weeks after injection. There was no RGC apoptosis in BBS control group and normal group. The level of anti-HSP27 in serum and cerebrospinal fluid of HSP27 sensibilization group occurred at 4 and 6 weeks after injection respectively, decreased with prolongation of injection time. Compared with BBS control group and normal group, the RGC apoptosis rate, anti-HSP27 level in serum and cerebrospinal fluid of HSP27 sensibilization group were significantly increased (P<0.05). There was no significant difference of the RGC apoptosis rate, anti-HSP27 level in serum and cerebrospinal fluid between BBS control group and normal group (P>0.05). ConclusionsHSP27 sensibilization could promote the RGC apoptosis. The variation trend of anti-HSP27 level in cerebrospinal fluid is consistent with the RGC apoptosis.
Objective To investigate the effect of ursolic acid on the proliferation and apoptosis of human osteosarcoma cell line U2-OS and analyze its mechanism. Methods Human osteosarcoma cell line U2-OS was divided into 4 groups, which was cultured with ursolic acid of 0, 10, 20, and 40 μmol/L, respectively. At 0, 24, 48, and 72 hours after being cultured, the cell proliferation ability was detected by cell counting kit 8 (CCK-8). At 48 hours, the effects of ursolic acid on cell cycle and apoptosis of U2-OS cells were measured by flow cytometry. Besides, the expressions of cyclin D1 and Caspase-3 were detected by real-time fluorescent quantitative PCR and Western blot. Results CCK-8 tests showed that the absorbance (A) value of each group was not significant at 0 and 24 hours (P>0.05); but the differences between groups were significant at 48 and 72 hours (P<0.05). Flow cytometry results showed that, with the ursolic acid concentration increasing, the G1 phase of U2-OS cells increased, the S phase and G2/M phase decreased, and cell apoptosis rate increased gradually. There were significant differences between groups (P<0.05). Compared with the 0 μmol/L group, the relative expressions of cyclin D1 mRNA and protein in 10, 20, and 40 μmol/L groups significantly decreased (P<0.05); whereas, there was no significant difference in relative expression of Caspase-3 mRNA between groups (P>0.05). However, with the ursolic acid concentration increasing, the relative expressions of pro-Caspase-3 protein decreased and the relative expressions of activated Caspase-3 increased; there were significant differences between groups (P<0.05). Conclusion Ursolic acid can effectively inhibit the proliferation of osteosarcoma cell line U2-OS, induce the down-regulation of cyclin D1 expression leading to G0/G1 phase arrest, increase the activation of Caspase-3 and promote cell apoptosis.
ObjectiveTo introduce the relationship between the apoptosis hepatocyte and its genic mediation and the ischemia of portal vein. MethodsThe combination of related literatures and our research findings were made.ResultsPortal vein ischemia may induced hepatocyte apoptosis, p53 and bcl2 gene alternatively adjust hepatocyte apoptosis. Expression of p53 gene is enhanced in hepatic tissue when hepatocyte apoptosis is not obvious, but after 24-72 h of portal vein ischemia, when hepatocyte apoptosis is obvious, enhanced expression of p53 gene or reduced expression of bcl2 gene occur. There exists close relationship between portal vein ischemia and hepatocyte apoptosis. Conclusion Apoptosis hepatocyte is involved in organic atrophy after ischemia of portal vein, and p53 and bcl2 gene alternatively adjust hepatocyte apoptosis. At present, the mechanism of apoptosis of hepatocyte induced by ischemia of portal vein is not clear, which needs further study.
【Abstract】 Objective To investigate the effect of verapamil on apoptosis, calcium and expressions of bcl-2 and c-myc of pancreatic cells in ischemia-reperfusion rat model. Methods Wistar rats were randomly divided into three groups: control group (n=10); ischemia-reperfusion group (n=10); verapamil treatment group (n=10). The anterior mesenteric artery and the celiac artery of rats in both ischemia-reperfusion group and verapamil treatment group were occluded for 15 min followed by 12-hour reperfusion. Verapamil (1 mg/kg) was injected via caudal vein to the rats in verapamil treatment group 15 min before occlusion and 1 hour after the initiation of reperfusion, respectively; and ischemia-reperfusion group was given the same volume of salient twice intravenously. Pancreatic tissues were collected from the dead rats after twelve hours since the reperfusion. The pathologic characters of pancreatic tissue were observed under light microscope; The level of calcium in the tissue was measured by atomic absorption spectrometer; TUNEL was used to detect apoptosis of pancreatic cells; and the expressions of c-myc and bcl-2 in the cells were also analyzed by immunohistochemistry technique and flow cytometry. Results The pathologic change in verapamil treatment group was less conspicuous than that of ischemia-reperfusion group. Both the calcium level and the number of apoptotic cells in verapamil treatment group were less than those of ischemia-reperfusion group 〔(411.1±55.8) μg/g dry weight vs (470.9±31.9) μg/g dry weight, P<0.05 and (9.5±2.9)% vs (18.4±3.1)% 〕, P<0.05. After taking verapamil, the number of apoptotic cells decreased, whereas the expressions of bcl-2 and c-myc increased. The fluorescent indexes of bcl-2 and c-myc in verapamil treatment group were significantly higher than those of ischemia-reperfusion group (1.72±0.11 vs 1.41±0.07, P<0.05; 1.76±0.19 vs 1.55±0.13, P<0.05. Conclusion Ischemia-reperfusion injury can induce apoptosis of pancreatic cells. Verapamil could protect the injured pancreatic tissue by reducing the level of calcium, stimulating the expressions of bcl-2 and c-myc and inhibiting apoptosis of pancreatic cells.
【Abstract】Objective To research relation of apoptosis muscular cell in 103Pd radioactive stent of dog biliary muscular formation and inhibition of biliary ductal stricture. Methods Twelve dogs were randomly divided into two groups, which were general stent group and 103Pd radioactive stent group. General stent and 103Pd radioactive stent were respectively put into extrahepatic biliary tract of two groups. After 30 days all dogs were killed, and biliary tract were taken out. Apoptotic cells were detected by immunohistochemical methodsand agar electrophoresis, and nucleus browyellow was positive cell. Dog biliary duct cross-sections were stained by hematoxylin-erosin; area and perimeter of lumen,thickness of inner membrane and stenosis degree in bile duct were analysed by image analysis software of computer.Results The apoptotic biliary duct smooth muscle cell [(87.9±7.96)/cm2] was more significantly increased in the 103Pd radioactive stent group than in the general stent group [(5.6±0.51)/cm2], P<0.05; and comparing with the general stent group, the 103Pd radioactive stent significantly reduced biliary muscular formation thickness. Conclusion The result shows that 103Pd radioactive stent can inhibit proliferation of biliary ductal smooth muscle cell.
Objective To observe the structural changes of urinary center and the expression of Bcl-2 after conus medullaris injury in rats brain so as to explore the possible influence factors of degeneration in brain. Methods Thirty-six adult Sprague-Dawley rats were randomly divided into experimental group (n=30) and control group (n=6). In the experimental group, the conus medullaris injury model was established by cutting off the spinal nerve below L4, and no treatment was done in the control group. The modeling operations in the experimental group were successful, and 2 rats died at 3 months and 5 months after modeling operation respectively, which may be caused by renal failure or urinary tract infection. In the experimental group, 6, 6, 6, 5, and 5 rats were killed at 1 day, 1 week, and 1, 3, 6 months after operation respectively, and 1 rat was killed at each time point in the control group. The dorsolateral tissue of the pontine tegmentum was harvested to perform HE staining and Bcl-2 immunohistochemical SP staining. Results HE staining showed that there was no obvious difference between the experimental group and the control group at 1 day after operation, the neurons were densely packed, arranged neatly, and the nucleoli were clear; at 1 week, the space between the neurons in the experimental group were slightly widened; at 1 month, nucleus retraction in some neurons happened in the experimental group; at 3 and 6 months, the nuclei in the experimental group were more and more condensed, and even some cells disappeared. Bcl-2 immunohistochemical SP staining showed that the expression of Bcl-2 in the control group was weakly positive. The positive expression of Bcl-2 was found at 1 day after operation in the experimental group; the positive expression of Bcl-2 at 7 days after operation was significantly higher than that in the control group, and reached the peak; the positive expression of Bcl-2 decreased gradually at 1, 3, and 6 months after modeling operation, but it was still higher than that of the control group. Conclusion The urinary center appears structure degeneration and necrocytosis after conus medullaris injury in rats brain. The elevated expression of Bcl-2 may be associated with brain tissue repair and function remodeling.