Objective To investigate the pathogenesis of acute lung injury in rats induced by intra-peritoneally injection of perforative peritonitis ascitic fluids（PPAF） and the role of L-arginine （L-Arg） in acute lung injury in this model. Methods Perforative peritonitis （PP） models were established in 60 rats and PPAF were collected. Forty-eight rats were randomly divided equally into NS group，PPAF group, and L-Arg group. Rats were randomly subjected to death at 7 h and 12 h. Peripheral blood WBC were counted，levels of NO and malondialdehyde （MDA） in serum were examined. Lung injury score and wet/dry ratio were evaluated， and level of myeloperoxidase （MPO） in lung tissues and lung cell apoptosis were tested. Results WBC count of peripheral blood, levels of NO and MDA in serum， level of MPO in lung tissue, lung injury score， wet/dry ratio， and lung cell apoptosis rate in PPAF group were significantly higher than that in NS group at each time point（P＜0.01）. Level of NO in serum in L-Arg group was higher than that in PPAF group （P＜0.01）， but lower level of MDA in serum， lower level of MPO in lung tissue and lung injury score，lower wet/dry ratio， and lung cell apoptosis rate were observed in L-Arg group（P＜0.05）. In PPAF group and L-Arg group， level of NO in serum， wet/dry ratio, and lung cell apoptosis rate were higher at 12 h than that at 7 h（P=0.000）. Serum NO level was in negative correlation with serum MDA level （r=-0.257，P=0.021）， MPO level in lung tissue（r=-0.444， P=0.011），and lung cell apoptosis（r=-0.351， P =0.010） in PPAF group and L-Arg group， but serum MDA level was in positive correlation with cell apoptosis（r=0.969， P＜0.001） in each group. Conclusions Acute lung injury rats model can be established by intra-peritoneally injection of PPAF. Enhanced oxidizing reaction and cell apoptosis take part in the occurrence of acute lung injury. L-Arg plays a protective role in acute lung injury.
Objective To investigate the role of chemokine receptor CXCR7 in the development and progression of pancreatic carcinoma. Methods The short hairpin RNA (shRNA) targeting CXCR7 was designed and delivered into AsPC-1 pancreatic carcinoma cells to knock down CXCR7 expression. The cell proliferation, cell cycle, and apoptosis after CXCR7 knockdown was determined by MTT and flow cytometry, respectively. The invasive ability of pancreatic carcinoma cells was evaluated by using the Transwell system. Results Compared with the blank control group (BC group), transfection of AsPC-1 cells with CXCR7-shRNA resulted in a significantly decreased expression of CXCR7 at both mRNA and protein levels (P<0.05), and the ability of proliferation and invasion significantly decreased (P<0.05). Knockdown of CXCR7 also significantly increase apoptosis (P<0.05), induce cell cycle arrest at G0/G1 phase (P<0.05). Conclusions Taken together, the present study showes that the knockdown of CXCR7 expression may play an important role in pancreatic carcinoma development, invasion, and metastasis, CXCR7 may be a potential therapeutic target for the treatment of pancreatic carcinoma.
Objective To investigate the inhibitory effect of survivin antisense oligonucleotides (ASODN) on proliferation of pancreatic cancer cells PANC-1. Methods The ASODN and sense oligodeoxynucleotides (SODN) were complementary to survivin sequences. FAM-marked ASODN was transfected into PANC-1 cells mediated by positive ion liposome as ASODN group. Blank control group (normal cells), negative control group (normal medium)， and SODN group were established for comparison. The transfection efficiency was detected by flow cytometry (FCM) after transfection; MTT assay was used to detect cytotoxicity; Cell morphological changes were examined by transmission electron microscopy; The cell cycle and apoptotic rate were analyzed by FCM; Immunohistochemical staining techniques were used, and the expressions of survivin were observed under light microscopy, examined and analysed by computer image. Results ①The transfection efficiency was 31.9%, 37.4%, 41.4%, 52.6%, 24.2%, 11.4%, 16.1%, and 15.5% when the transfecting concentration of ASODN was 50, 100, 150, 200, 250, 400, 600, and 800 nmol/L, respectively; The transfection efficiency was 12.0%, 50.8%, and 11.2% when the inoculated cells was 2×104/well, 2×105/well, and 2×106/well, respectively; The transfection efficiency was 58.8%, 34.0%, and 23.6% when 2 μl, 3 μl, and 4 μl liposome was used during transfection, respectively. ②Cell gap was oversize, morphous was round, adherent cells were less after transfection under fluorescence microscope. ③The inhibition rate in the ASODN group was higher than that in each control group (Plt;0.05) on 24, 36, 48 h after treating by survivin ASODN, which increased as time prolonged (Plt;0.05). ④The apoptosis showed a ladder-shaped line in the ASODN group. ⑤Apoptotic morphology was demonstrated in the ASODN group, such as apoptotic cells with nuclear chromatin highly concentrated, crescent nuclear staining aggregated by the side nuclear membrane, nucleolus disappeared by AO and EB stains. ⑥The apoptotic rate 〔（38.1±3.4）%〕 in the ASODN group was higher than that in the SODN group 〔（4.16±1.7）%〕, Plt;0.05. ⑦G2/M cell cycle arrested in the ASODN group. ⑧After transfection, the expression of survivin protein in the ASODN group was significantly lower than that of each control group (Plt;0.05). Conclusions The optimal transfection conditions are as following: the cell count of 2×105/well, concentration of ASODN 200 nmol/L, and cationic liposome oligofectamine 2 μl, respectively. Survivin ASODN can inhibit the proliferation of pancreatic cancer cells and induce their apoptosis.
ObjectiveThis study is aimed to determine the expression of ubiquitin-specific peptidase 39 (USP39) protein in the colorectal cancer (CRC) tissues, and the effect of silencing USP39 gene on the cell growth and cell cycle distribution of CRC cells.Methods① The expressions of USP39 protein in CRC tissues and its paracancerous tissues were determined by immunohistochemical staining method. ② By lentiviral infection, Lv-shUSP39 (KD-1 and KD-2 group) and Lv-shCon (shCon group) were transferred into SW1116 and HCT116 cells, and cells of blank control group did not received any treatment (Con group). To determine the role of USP39 gene in cell growth, MTT assay was performed to draw growth curve, and cell cycle distribution of CRC cells in the 4 groups were determined by flow cytometer.Results① The expression of USP39 protein was higher in CRC tissues compared to adjacent tissues (P=0.007). ② For SW1116 and HCT116 cells, the cell proliferation ability of KD-1 and KD-2 groups were remarkably decreased than those in corresponding shCon and Con groups on 3, 4, and 5-day (P<0.05). ③ Flow cytometry assay showed that, the percentage of G0/G1 phase cells were decreased obviously (P<0.05), while increased significantly in percentage of G2/M phase and number of sub-G1 phase cells in KD-1 group compared with that in the Con group and shCon group of SW1116 and HCT116 cells (P<0.05).ConclusionsThe expression of USP39 protein is highly expressed in CRC tissues. Knockdowning of USP39 gene can inhibit cell proliferation and promote cell apoptosis.
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.
Objective To review the current researches about tumor necrosis factor-related apoptosis ligand (TRAIL) and its receptors in gastric carcinoma. Methods Relevant articles of researches on TRAIL and its receptors in gastric carcinoma were searched in electronic databases of PUB-MEDLINE and Chinese Journal Fulltext Database. Results The reported TRAIL expression level of gastric carcinoma was diverse, which was highly correlated to the histological differentiation degree, serosa invasion and lymph node metastasis. Its receptors DR4 and DR5 were both positive in gastric carcinoma tissue, while some researches reported DcR1 and DcR2 were also positive expressed. caspase-3, -8 and survivin were the important factors for regulation of TRAIL signal pathway. 5-Aza-CdR, doxorubicin, 5-fluorouracil, α-TOS and X-ray irradiation might enhance the TRAIL-induced apoptosis of gastric carcinoma cells. Conclusion Gastric carcinoma may be potentially sensitive to TRAIL targeting therapy, but the mechanism of TRAIL-induced apoptosis is quite complex and is regulated by multi-factors. Up to now, there are still many issues to research further, such as how to efficiently enhance and regulate the TRAIL-induced apoptosis of gastric carcinoma, whether any potential toxicities existing, etc.
Objective To investigate the expression of miR-31a-5p in myocardial infarction (MI) mice and its potential mechanism. Methods A dataset was downloaded from the gene expression database, and miR-31a-5p and its predicted target gene hypoxia-inducible factor-1α (HIF-1α) were screened using bioinformatics methods. The MI model was established by ligating the left anterior descending branch of the coronary artery in C57BL/6J male mice which were randomly divided into sham and MI groups (n=6 in each group). The in vitro hypoxic cell model was induced by treatment of H9c2 cells with cobalt chloride (CoCl2) and divided into a control group, a model group, a NC group, a miR-31a-5p mimic group and a miR-31a-5p inhibitor group. The degree of myocardial tissue fibrosis was stained by Masson and analyzed. The expression levels of miR-31a-5p and HIF-1α mRNA in mouse myocardial tissues and H9c2 cells were detected by qRT-PCR. Western blotting was used to detect the expression levels of B-cell lymphoma 2 (Bcl-2), cleaved-caspase 3 apoptotic protein in mouse myocardial tissues and HIF-1α and apoptotic protein in H9c2 cells, respectively. The dual luciferase reporter gene assay was used to verify the targeting relationship between miR-31a-5p and HIF-1α. Results Masson staining showed significantly increased fibrosis in MI mice (P<0.000 1); miR-31a-5p, cleaved-caspase 3 were significantly elevated and Bcl-2 was decreased in MI mice and CoCl2 treated H9c2 (P<0.05). The results of dual luciferase reporter assay showed that the relative luciferase activity of miR-31a-5p mimic cotransfected with HIF-1α-3'-UTR WT plasmid was reduced (P<0.000 1); miR-31a-5p mimic decreased HIF-1α expression and increased apoptotic protein levels in CoCl2 induced H9c2 cells (both P<0.05), while miR-31a-5p exerted the opposite effect. Conclusion miR-31a-5p can aggravate apoptosis in myocardial ischemia by targeting HIF-1α.
Objective To review the literature reports on research progress of Heme oxygenase 1 (HO-1) modified mesenchymal stem cells (MSCs). Methods The significance, effects, and related mechanism of HO-1 modification of MSCs were summarized by consulting the related literatures and reports of HO-1 modification of MSCs. Results HO-1 modification of MSCs has important research value. It can effectively enhance the anti-oxidative stress and anti-apoptotic properties of MSCs in complex internal environment after transplantation into vivo. It can also effectively enhance the immune regulation function of MSCs. It can improve the anti-injury, repair, and immune regulation effect of MSCs in various disease models and research fields. Conclusion The basic research of HO-1 modified MSCs has made remarkable progress, which is expected to be applied in clinical trials and provide theoretical basis and reference value for stem cell therapy.
【Abstract】ObjectiveTo explore the effects of p38 mitogenactivated protein kinase (MAPK) on apoptosis of small intestinal epithelial cells after transplantation in rats. MethodsSmall intestinal transplantation was performed in SD and Wistar rats. The recipients were divided into three groups: isograft group (Wistar→Wistar group), allograft group (SD→Wistar group) and allograft+cyclosporine A group (SD→Wistar+CsA group). The grafts were harvested on day 1, 3, 5 and 7 after operation. All graft samples were subjected to histological examination. The apoptosis of graft epithelial cells was detected by TUNEL method. p38 MAPK was measured by Westernblotting method and serum TNFα was determined by ELISA. ResultsMild, moderate and severe rejection reaction occurred in the SD→Wistar group, it was showed that the number of apoptotic cells increased with the severity of the rejection reaction by TUNEL. In SD→Wistar group, the numbers of apoptotic cells were significantly higher than those of the other two groups （P＜0.01）. The severity of rejection reaction in SD→Wistar+CsA group was less than that of SD→Wistar group and the number of apoptotic cells increased with the severity of the rejection reaction (P＜0.01). The level of serum TNFα varied with the apoptotic degree of small intestinal epithelial cells in SD→Wistar group and SD→Wistar+CsA group （P＜0.01）. The expression of p38 MAPK increased with the number of the apoptotic cells in SD→Wistar group and SD→Wistar+CsA group （P＜0.01）, but there was no evident change in Wistar→Wistar group （Pgt;0.05）. The expression of p38 MAPK and the level of serum TNFα were positively correlated with apoptosis in small intestinal rejection after transplantation （r=0.875， P＜0.01； r=0.837， P＜0.01）. p38 MAPK and TNFα were also positively correlated （r=0.826，P＜0.01）. ConclusionApoptosis plays an important role in small intestinal rejection. p38 MAPK is involved in apoptosis and is an important regulator in signal pathway of cell apoptosis.
ObjectiveTo research the biological characteristics of different generations of rabbit nucleus pulposus cells (NPCs) that were cultured with natural culture and subculture method.MethodsThe thoracolumbar segments of New Zealand white rabbits (6-8 weeks old and weighing 1.5-2.5 kg) were obtained and nucleus pulposus were isolated from disc regions. And NPCs were harvested by enzymatic digestion from nucleus pulposus. Primary NPCs were counted as P0 generation. Then, NPCs were passaged by trypsin and counted as P1, P2, P3 with a totle of 4 generations. P0 to P3 generations NPCs were separately examined by observation of cell morphology and proliferation time, detection of apoptosis rates of cells by flow cytometry, and detection of hypoxia-inducible factor 1α (HIF-1α), matrix metalloproteinases 2 (MMP-2), Aggrecan, and collagen type Ⅱ proteins by immunofluorescence and Western blot.ResultsThe morphology of NPCs transformed from triangular or polygonal in P0 generation to spindle in P3 generation; the characteristic vacuolated cells gradually disappeared; and the cell volume and cell proliferation time increased. The cell apoptosis rates were 5.47%±0.91%, 13.77%±2.42%, 33.46%±1.82%, and 38.76%±1.50% from P0 to P3 generations, with the increase of culture time, and there were significant differences between 4 generations (P<0.05). Immunofluorescence staining showed that with the increase of cells generation, the fluorescence intensity of HIF-1α, collagen type Ⅱ, and Aggrecan decreased, and the fluorescence intensity of MMP-2 increased. Western blot results showed that the relative expression of HIF-1α protein was high in P0 generation, the P1 generation has a rising trend, and then gradually decreased; the differences between generations were significant (P<0.05). The relative expression of collagen type Ⅱ protein decreased from P0 to P3 generations and there were significant differences between generations (P<0.05). The relative expression of Aggrecan protein decreased from P0 to P2 generations and there were significant differences between generations (P<0.05); but no significant difference was found between P2 and P3 generations (P>0.05). The relative expression of MMP-2 protein increased significantly in P3 generation; except that the difference between P0 and P2 generations was not significant (P>0.05), the significant differences were found between the other generations (P<0.05).ConclusionRabbit NPCs degeneration model was successfully established by the natural culture and subculture method. Transforming of NPCs morphology, increasing of cell apoptosis rates, decreasing of anabolism, and increasing of catabolism were presented in NPCs degeneration model.