Objective To observe the eotaxin expression of rat airway smooth muscle cells ( ASMCs) induced by serum from asthmatic rats, and explore the possible mechanism. Methods ASMCs isolated fromrat tracheas were cultured in vivo. Then they were treated with serum from asthmatic rats, or treated with serum and dexamethasone simultaneously. The level of eotaxin protein in supernatant and eotaxin mRNA in ASMCs were measured by ELISA and reverse transcription-polymerase chain reaction. The expression of cAMP in ASMCs was examined by radioimmunoassay. Results After the treatment with sensitized serum, the eotaxin level in supernatant and mRNA expression in ASMCs were significantly higher [ ( 107. 09 ±7. 12) ng/L vs. ( 0. 63 ±0. 56) ng/L, P lt; 0. 05; 1. 39 ±0. 04 vs. 0. 05 ±0. 01, P lt;0. 05] , and the level of cAMP in ASMCs was significantly lower compared with the control group [ ( 17. 58 ±3. 62) ng/L vs. ( 32. 39 ±3. 36) ng/L, P lt; 0. 05] . After intervened by the sensitized serum and dexamethasone simultaneously, the protein and mRNA expressions of eotaxin were lower compared with those intervened by sensitized serumalone [ ( 64. 18 ±4. 04) ng/L and 0. 77 ±0. 19] . The level of eotaxin in supernatant was negatively correlated with cAMP level in ASMCs ( r = - 0. 788, P lt; 0. 01) . Conclusions There is anautocrine function in ASMCs as inflammatory cells after stimulation with sensitized serum. Eotaxin may play an important roll in the pathogenesis of asthma via a cAMP-dependent pathway.
Objective To extract and identify primary culture rat pulmonary arterial smooth cells ( PASMCs) , and investigate the effects of hypoxia on the proliferation of PASMCs. Methods Rat PASMCs were separated by the method of tissue block anchorage, and the cellular morphology was observed under light microscope. The cells were identified by projection electron microscopy, and α-smooth muscle actin ( α-SMactin)in the cells was identified by immunohistochemistry and immunofluorescence. The primary cultured PASMCs were exposed to normoxic and/ or hypoxia condition for 2, 6, 12, 24, 48 hours respectively, thenMTT assay and PCNA ( proliferating cell nuclear antigen) immunohistochemistry were used to detect the proliferation of PASMCs. Results The cells tended to be long spindle and grew in the “peak-valley”mode under light microscope. Immunology results showed that endochylema was stained in brownish yellow, and the positive rate was beyond 96% . There were dense patch, dense body and many filaments in endochylema under projection electron microscopy. MTT assay demonstrated that the A values of PASMCs expose to hypoxia were higher than that of nomoxia. Comparing with normoxia, the A values of PASMCs exposed to hypoxia increased after 12 hours ( P lt;0. 05) , significantly increased after 24 hours ( P lt;0. 01) . Compared with 2 hours’exposure to hypoxia, the A values increased after 12 hours( P lt; 0. 05) , markedly increased after 24 hours ( P lt; 0. 01 ) , which after 48 hours was similar with 24 hours. The result of PCNA immunohistochemistry was consistent with that of MTT. Conclusions The tissue explants adherent method is simple and convenient, and can easily obtain rat PASMCs with high purity and stability. Hypoxia canpromote the proliferation of PASMCs.
Abstract: Objective To determine the effects of oxidative stress reaction on intima hyperplasia after autologous vein grafting. Methods Seventy female SpragueDawley(SD) rats were randomly divided into a control group(n=10) and an experimental group (n=60). The experimental group was then divided into six time points of one day; one, two, four, and six weeks; and two months after surgery; with 10 rats for each time point. Autologous vein grafting models were established. At each time point the designated rats were anaesthetized, and the grafts were isolated and stained with HE. The same length of external jugular vein was cut from each rat in the control group. The neointima to tunica media area ratios (I/M) were measured with acomputerized digital image analysis system. Nuclear factorkappa B (NF-κB) and copper zinc superoxide dismutase (CuZnSOD) were detected byimmunohistochemistry. The concentration of malondialdehyde (MDA) in serum was analyzed by colorimetry. Results In the control group, expression levels of NF-κB and CuZnSOD were low. In the experimental group, expression of NF-κB increased after the operation and peaked two weeks later. The plateau was sustained for about one month, and then the level of expression declined gradually, reaching the baseline at the twomonth time point. The expression of CuZnSOD increased gradually after the operation and peaked one week later, then declined to the normal level after 2-3 weeks at the plateau. In the control group, the concentration of serum MDA was 4.966±1.346 nmol/ml. In the experimental -group, the-MDA concentration increased dramatically after the operation, then-declined from its highest level at the oneday time point (21.161±2.174 nmol/ml) to the normal level at two months (6.208±2.908 nmol/ml) after the operation (P＜0.05). In the control group, I/M was 0.2096±0.0253, while in the experimental group, it was higher one week after the operation (0.6806±0.0737) and peaked at four weeks (1.4527±0.0824), falling to 1.0353±00656 at six weeks and 0.9583±0.0516 attwo months (P＜0.05) for the experimental and control groups). Conclusion Endothelial cell injury initiates an oxidative stress reaction after autologous vein grafting and augments inflammation by activating NF-κB, thus playing an important role in inducing restenosis of the grafted vein.
Objective To study the inhibitory effect of RNA interference (RNAi) on bcl-2 expression of vascular smooth muscle cells （VSMCs) in rabbit. Methods The expression vector of bcl-2 gene-targeting small interference RNA (pshRNA-bcl-2) was constructed and was transfected into VSMCs by lipofectamine, and the unloaded vector was used as control. The expression of bcl-2 mRNA was identified by RT-PCR and Western blot, respectively. The growth of the transfected VSMCs was examined by MTT. Results The pshRNA-bcl-2 may inhibit the expression of bcl-2 gene at the levels of transcription and translation. There were significant differences (P＜0.01) of the expressions of bcl-2 mRNA between the VSMCs that were transfected with pshRNA-bcl-2 and the ones in plasmid transfected group and control group, respectively. There was a significant difference (P＜0.01) in the growth of VSMCs between the plasmid transfected and the control groups. Conclusion The plasmid containing the small interference RNA of bcl-2 may have an inhibitory effect on the cell growth and endogenous expression of bcl-2 gene at the levels of transcription and translation in VSMCs.
Objective To investigate the effects of simvastatin on the collagen synthesis of rat pulmonary arterial smooth muscle cells ( PASMCs ) induced by hypoxia. Methods Under hypoxic condition, rat PASMCs were cultured with different concentrations of simvastatin. Collagen synthesis of PASMCs with or without simvastatin were measured by 3H-proline incorporation assay. The mRNA expression of TGF-β1 and the contents of super oxide dismrtase ( SOD) ,malondialdehyde ( MDA) in mediumwere also measured. Results The incorporation data of 3H-TdR in the hypoxia group was significantly increased as compared with that in the control group ( P lt;0. 01) , and simvastatin significantly reduced the incorporation data of 3H-TdR induced by hypoxia. The expression of TGF-β1 mRNA in the hypoxia group was significantly increased as compared with that in the control group ( P lt; 0. 01 ) , and simvastatin could significantly inhibited hypoxia-induced expression of TGF-β1 mRNA in a dose-dependent manner. Compared with the hypoxia group, the expression of TGF-β1 mRNA decreased by 55% in simvastatin( 10 - 6mol /L) group ( P lt; 0. 01) , and by 70% ( P lt; 0. 01) in simvastatin ( 10 - 5mol /L) group. Compared with the control group, the activity of SOD was reduced and the contents of MDA were increased significantly in the hypoxia group. Simvastatin can increase the activity of SOD and reduced the content of MDA in a dose-dependent manner. Conclusions Simvastatin can decreases collagen synthesis of PASMCs. This effect might be explained that simvastatin can reduce lipid peroxide and expression of TGF-β1 mRNA.
ObjectiveTo explore a simple, efficient method for primary culture in vascular smooth muscle cells of diabetic rat, to establish a long-term stable diabetic vascular smooth muscle cell model in vitro, and lay the foundation for the study of diabetes chronic vascular lesions. MethodsTwenty diabetic Wister rats models were self-made by using streptozotocin intraperitoneal injection plus high fat and sugar feeding, the vascular smooth muscle cells in vitro was cultured by a modified enzymatic digestion. ResultsThe diabetic rat models were successfully established, the vascular smooth muscle cells cultured in vitro by modified enzyme digestion grew fast, the cell survival was 96%, it could meet the requirements for cell experiment in vitro. ConclusionComparing with the traditional method, the modified enzymatic digestion method is simple, economic, high survival rate.
Objective To investigate the influence of RNA interference targeting c-Jun gene on the proliferation of rat vascular smooth muscle cells (VSMCs). Methods The experiment was performed with c-Jun siRNA （c-Jun siRNA group）, control reverse sequence siRNA (control siRNA group) or no siRNA (control group). VSMCs were transfected with siRNA targeting c-Jun gene by liposome. Effects of c-Jun siRNA on mRNA and protein expressions of c-Jun were examined by RT-PCR analysis and Western blot respectively. MTT test and 3H-TdR incorporation were used to detect VSMCs proliferation. Cell cycle analysis of VSMCs in vitro was determined by flow cytometer. Results The expression levels of mRNA and protein of c-Jun in c-Jun siRNA group were significantly lower than those in control group （P＜0.05， P＜0.01). There was no significant difference between control group and control siRNA group （Pgt;0.05）. Proliferation activity of VSMCs decreased significantly in c-Jun siRNA group compared with that in control group （P＜0.05） and VSMCs was blocked in the G0/G1 phase of cell cycle significantly （P＜0.05）. There was no significant difference between control group and control siRNA group （Pgt;0.05）. Conclusion c-Jun gene silenced by RNA interference can inhibit VSMCs proliferation effectively in vitro.
Previous studies have shown that growth arrest, dedifferentiation, and loss of original function occur in cells after multiple generations of culture, which are attributed to the lack of stress stimulation. To investigate the effects of multi-modal biomimetic stress (MMBS) on the biological function of human bladder smooth muscle cells (HBSMCs), a MMBS culture system was established to simulate the stress environment suffered by the bladder, and HBSMCs were loaded with different biomimetic stress for 24 h. Then, cell growth, proliferation and functional differentiation were detected. The results showed that MMBS promoted the growth and proliferation of HBSMCs, and 80 cm H2O pressure with 4% stretch stress were the most effective in promoting the growth and proliferation of HBSMCs and the expression level of α-smooth muscle actin and smooth muscle protein 22-α. These results suggest that the MMBS culture system will be beneficial in regulating the growth and functional differentiation of HBSMCs in the construction of tissue engineered bladder.
Objective To observe whether umbilical cord mesenchymal stem cells (UCMSCs) can differentiate into the smooth muscle cells (SMCs) induced by bladder SMCs (BSMCs) conditioned medium so as to seek an alternative seed cells for the repair and reconstruction of the urology system. Methods UCMSCs and BSMCs were harvested from umbilical cord of full-term births and bladder tissues which were obtained from patients who underwent a radical cystectomy. BSMCs conditioned medium was prepared by mixing supernatant of BSMCs at passages 1-5 with complete medium at ratio of 1 ∶ 1. UCMSCs at passage 3 were cultured with BSMCs conditioned medium (induced group, group A) and complete medium (control group, group B), respectively; simple BSMCs served as positive control group (group C). The morphological changes of co-cultured UCMSCs were observed by inverted phase microscope, the expressions of α-smooth muscle actin (α-SMA), Calponin, and smooth muscle myosin heavy chain (SM-MHC) of UCMSCs were tested by immunofluorescence staining and Western blot at 7 and 14 days. Results The morphology of UCMSCs in group A started to change from a polygonal and short spindle shape to a large and spindle shape after co-culture, which was similar to BSMCs morphology; but the morphology of UCMSCs did not change obviously in group B. Immunofluorescence staining showed that the expressions of α-SMA, Calponin, and SM-MHC were positive in group C. At 7 days, the expression of α-SMA could be observed in groups A and B; at 14 days, the positive expression of α-SMA increased gradually in group A, but it did not increase in group B. At 7 days, a positive expression of Calponin could be observed in group A, and positive expression increased obviously at 14 days; the expression of Calponin could not be observed at 7 and 14 days in group B. However, the expression of SM-MHC could not be observed in groups A and B. The results of Western blot showed the expressions of α-SMA, Calponin, and SM-MHC protein were consistent with the results of immunofluorescence staining. Conclusion UCMSCs have the potential of differentiation into SMCs and may be a potential seed cells for bladder tissue engineering.
【Abstract】Objective To investigate the irradiating effect of low intensive microwave (LIM) on pathological process of blood vessel restenosis(RS) and assess the probability of LIM irradiation to prevent was used RS.Methods Fortyfour male healthy New Zealand rabbits were randomly divided into 2 groups. Fogarty catheter traumatize to the tunica intima of iliac artery so as to establish RS models. Two thousand four hundred and fifty MHz microwave with different power of 2 ,5 and 10 mW/cm2 was used, locally to irradiate EIA in irradiating group (1 h/d). Specimens were obtained at different time of 3,7,14 and 28 d after operation. Morphological changes of tissues were observed with HE and EF staining and the area of tunica intima, tunica media and the rate of cavity stenosis were analyzed with image analysis system; apoptosis was detected with TUNEL; phenotype and microstructure of VSMC were observed with TEM. Results After microwave irradiating, inflammatory reaction in early period was suppressed, mural thrombus decreased, the proliferation and migration of VSMC depressed, the area of tunica intima and the rate of cavity stenosis obviously reduced comparing with the control group (P＜0.01). The rate of apoptosis cells showed that there were no obvious differences among each group on 3 d after operation (Pgt;0.05). At other different time, however, the rate of apoptosis cells in irradiating groups obviously increased than that of the control group (P＜0.01), particularly in the one with power of 5 mW/cm2 .The number of synthesis form VSMC in the control group occupied (93.50±3.45)% of the total number of VSMC on 14 d after operation. Most of VSMC appear contractile in irradiating group in which a lot of morphological changes of apoptosis in fibroblast and VSMC existed.Conclusion LIM irradiation could obviously prevented from pathologic procedure of RS. After LIM irradiating, inflammatory reaction in early period is suppressed, the proliferation and migration of VSMC depressed. LIM irradiation promotes cell apoptosis, effectively prohibites the occurring and development of RS. LIM irradiation has had relationship between quantity and effect, power span to effectively prohibit RS, particularly in the one with power of 5 mW/cm2.