共查询到20条相似文献，搜索用时 31 毫秒
1.
AIM: To investigate the effects of gonadotropin-releasing hormone (GnRH) analogue on the growth of breast cancer cell lines MCF-7 and MDA-MB-231 in vitro and to explore the related mechanisms with PI3K/Akt or ERK/MAPK pathways. METHODS: The proliferation of human breast cancer cell lines MCF-7 and MDA-MB-231 treatment with triptorelin was detected by MTT assay and the distribution of the cell cycle was determined by flow cytometry. The phosphorylation of the ERK1/2 and Akt was evaluated by Western blotting. RESULTS: Triptorelin inhibited the proliferation of MCF-7 cells at concentration of 10-5 mol/L after treated for 192 h or at concentration of 10-4 mol/L after treated for 168 h and 192 h. Triptorelin inhibited the proliferation of MDA-MB-231 cells at concentration of 10-4 mol/L after treated for 192 h (P<0.05).Treatment with triptorelin for 192 h at concentration of 10-4 mol/L had no statistical significance effect on phosphorylation of ERK1/2 and Akt(P>0.05).CONCLUSION: Inhibitory effect of GnRH analogue triptorelin on human breast cancer cells is not just the connection with the down-regulation of pituitary hormone, but also a direct inhibitory effect. The role may not be involved in the activation of ERK/MAPK and PI3K/Akt signaling pathways. 相似文献
2.
AIM: The effect of urotensin II (U-II) on proliferation of cultured pulmonary arterial smooth muscle cells (PASMCs) of rabbits and its mechanism are investigated. METHODS: PASMCs were isolated using explant technique. RPASMCs were incubated in serum-free medium with different concentrations of nicardipine, calcimodulin antagonist W7, PKC inhibitor H7 or MAPK inhibitor (PD98059), with or without U-II. RPASMC proliferation was examined by MTT assay and by the increase in [3H]-thymidine incorporation into DNA. RESULTS: U-II (10-9 mol/L-10-7 mol/L) increased A value of PASMCs by MTT assay and [3H]-thymidine incorporation in PASMCs in a dose-dependent manner. U-II induced a maximal effect at a concentration of 10-7 mol/L. A value and [3H]-thymidine incorporation rose 42.9% and 68.5% (P<0.05), respectively. U-II had no effect at a concentration of 10-10 mol/L. Nicardipine, W7, H7, PD98059 (10-7 mol/L-10-5 mol/L) inhibited the effect of U-II in inducing increase of A value and -thymidine incorporation in a dose-dependent manner, with the maximal inhibitory rate of 42.3%, 19.6%, 23.2%, 10.5% (P<0.05) in A value and 46.6%, 9.8%, 21.7%, 14.7% (P<0.05) in [3H]-thymidine incorporation at concentration of 10-5 mol/L, respectively. CONCLUSION: Our results suggest that U-II may induce proliferation of PASMCs of rabbits by Ca2+, CaM, PKC and MAPK signal transduction pathway. 相似文献
3.
AIM:To study the effect of farrerol (Far) on nicotine-induced proliferation of rat pulmonary smooth muscle cells (PASMCs), and further to explore its relationship with voltage-dependent potassium channels (Kv) 1.5 and Kv2.1. METHODS:Firstly, the effect of nicotine on the proliferation of PASMCs was detected by cell counting method, and the optimal concentration of nicotine was selected. Primary cultured PASMCs were randomly divided into 5 groups:normal control group, nicotine (1 μmol/L)group, nicotine (1 μmol/L) + Far (10-6 mol/L, 10-5 mol/L and 10-4 mol/L) Far group. The activity of caspase-3 was measured by apoptosis kit, the cell viability was measured by CCK-8 assay, the apoptotic rate was analyzed by flow cytometry. The expression of Kv1.5 and Kv2.1, and apoptosis-related factors Bcl-2 and Bax at mRNA and protein levels was determined by RT-qPCR and Western blot respectively. RESULTS:Nicotine at 1 μmol/L increased the number of PASMCs to the maximum extent (P<0.01). Nicotine at 1 μmol/L significantly reduced the caspase-3 activity and enhanced the cell viability of the PASMCs (P<0.01). Farrerol at 10-6~10-4 mol/L eliminated the effect of PASMCs induced by nicotine in a concentration dependent manner. Compared with control group, nicotine at 1 μmol/L significantly increased the proliferation and inhibited the apoptotic rate of rat PASMCs (P<0.01). The apoptotic rate of PASMCs in farrerol intervention group was significantly higher than that in nicotine group (P<0.01). Nicotine at 1 μmol/L significantly inhibited the expression of Kv1.5, Kv2.1 and Bax but increased the expression of Bcl-2 in PASMCs (P<0.01). Farrerol at 10-5 mol/L obviously inhibited the effect of PASMCs induced by nicotine. CONCLUSION:Farrerol eliminates nicotine-induced inhibition of caspase-3 and Bax, and enhancement of Bcl-2 in PASMCs by enhancing Kv1.5 and Kv2.1 expression. 相似文献
4.
AIM: To investigate the effects of 1,25-dihydroxyvitamin D3 on the proliferation of passively-sensitized human airway smooth muscle cells (HASMCs), and to explore its potential role in asthmatic airway remodeling.METHODS: HASMCs were passively sensitized with 10% serum from asthmatic patients.1,25-(OH)2D3 was used as the interventor.The effect of 1,25-(OH)2D3 on the cell proliferation and its optimal concentration were determined by MTT colorimetric assay.The cell cycle analysis was performed by flow cytometry.The expression of proliferating cell nuclear antigen (PCNA) was measured by the method of immunocytochemical staining.RESULTS: 1,25-(OH)2D3 at the concentrations of 10-9-10-7 mol/L markedly inhibited the cell proliferation and the maximum effect was observed at the concentration of 10-7 mol/L.This concentration of 1,25-(OH)2D3 markedly suppressed the PCNA-positive rate and hampered the G1/S transition in HASMCs passively-sensitized by asthmatic serum.CONCLUSION: 1,25-(OH)2D3 has direct inhibitory effects on the proliferation of passively-sensitized HASMCs in vitro, which may be concerned with the beneficial role of 1,25-(OH)2D3 on the prevention and therapy of asthmatic airway remodeling. 相似文献
5.
AIM: To investigate the effects of synthetical glucocorticoid dexamethasone(Dex) on the activation of two members of mitogen-activated protein kinase (MAPK) family, extracellular signal-regulated protein kinase1/2(ERK1/2) and p38 MAPK (p38) in human ovarian cancer cell line HO-8910. METHODS: The activation of ERK1/2 and p38 was determined by Western blot. RESULTS: Inhibition of activation of ERK1and ERK2 by10-7 mol/L Dex occurred at 5 min, with maximum up to 41% and 54% respectively at 30min (P<0.01), and sustained until 4 h. On the contrary, p38 activity was rapidly stimulated by 10-7 mol/L Dex, with maximum to 84% at15 min (P<0.01), and sustained till1h. Furthermore, these effects increased with the concentration of Dex(10-10-10-6 mol/L). RU486, an antagonist of glucocorticoid receptor (GR), did not affect these effects. CONCLUSION: Dex can rapidly inhibit ERK1/2 and stimulate p38 activation in a GR-independent manner in HO-8910cells, which might play a role in Dex-mediated growth inhibition in these cells. 相似文献
6.
AIM: To investigate the role of Rho-kinase signal pathway in rat cardiac fibroblasts (CFBs) proliferation and collagen synthesis induced by angiotensinⅡ (AngⅡ). METHODS: CFBs of neonatal Sprague-Dawley (SD) rats were isolated with the method of trypsin digestion and differential anchoring velocity. The CFBs were stimulated with AngⅡto induce fibrosis. Proliferation of CFBs was observed by MTT coloricmetric assay. Synthesis of collagen was detected by the hydroxyproline. The expression of Rho-kinase mRNA was examined using RT-PCR analysis. The extent of phosphorylation of myosin-binding subunit (MBS-P) of myosin phosphatase was quantified by Western blotting analysis, which was used to evaluate the activity of Rho-kinase.RESULTS: (1) Stimulation of neonatal SD rat CFBs with AngⅡ (10-7 mol/L) significantly increased CFBs proliferation and collagen synthesis (P<0.01). (2）Stimulation of neonatal SD rat CFBs with AngⅡ (10-7 mol/L) significantly increased the expression of Rho-kinase mRNA and rapidly activated Rho-kinase in a time-dependent manner. (3) Within a concentration coverage, hydroxyfasudil (H4413), a Rho-kinase inhibitor, effectively inhibited AngⅡ-induced CFBs proliferation and collagen synthesis (P<0.05 or P<0.01).CONCLUSION: Rho-kinase signal pathway may be one of the most important signal transducter for AngⅡ-induced CFBs proliferation and collagen synthesis in neonatal SD rats. 相似文献
7.
AIM:To investigate the effect of metallothionein(MT) on proliferation of rat vascular smooth muscle cells (VSMCs) stimulated by homocysteine and its mechanism. METHODS:VSMCs proliferation was measured by [3-H]-TdR incorporation, mitogen-activated protein kinase(MAPK)activity were determined by immunoprecipitation method, the intracellular contents of MT and malondialdehyde (MDA)were assayed by -hemoglobin saturation method and TBA reaction, respectively, and lactate dehydrogenase (LDH) leakage was measured by NADH oxidation. RESULTS:Hcy(10-6-10-4 mmol/L) stimulated [3-H]-TdR incorporation by the VSMCs in a concentration-dependent manner. Compared with control, [3-H]-TdR incorporation in VSMCs treated with 0.1 mmol/L Hcy was increased by 4.2 fold (P＜0.01). Meanwhile, Hcy enhanced MAPK activity, MDA formation and LDH release (P＜0.01)in a concentration-dependent manner. Treatment of VSMCs with MT alone did not change above parameters, compared with control. However, MT (10-6-10-4 mol/L)attenuated significantly Hcy-stimulated proliferation of VSMCs (P＜0.01)in a concentration-dependent manner. And MT inhibited obviously Hcy-induced activation of MAPK activity, MDA formation and LDH release. Preincubation of VSMCs with 0.5 mmol/L ZnCl2 for 6 h induced an increase cellular MT content by 5.7-fold (P＜0.01). The MT-overexpressed VSMCs resisted Hcy-stimulating action on MAPK activity, MDA formation and LDH leakage (P＜0.01). CONCLUSION:These results show that MT has an inhibitory effect on Hcy-induced VSMCs proliferation, and that MT could inhibit Hcy-stimulated MAPK activity and lipid peroxidation. 相似文献
8.
AIM: To investigate the effects of leptin on the expression of bile salt export pump (BSEP) and signaling pathway in human hepatocellular carcinoma cell line HepG2. METHODS: HepG2 cells were cultured in vitro. Leptin at concentrations of 10-8, 10-7 and 10-6 mol/L was used as a stimulating factor. The protein levels of adenosine monophosphate-activated protein kinase alpha subunit (AMPKa), phosphorylated AMPKa (p-AMPKa) and BSEP in the HepG2 cells at 24 h, 48 h and 72 h were detected by Western blotting. The optimal culture time and leptin concentration were selected, and compound C at concentration of 10 μmol/L was added to this group. The protein expression of BSEP was detected by Western blotting. RESULTS: Intervention of HepG2 cells with leptin for 72 h increased the protein expression of AMPKa gradually in a concentration-dependent manner, and leptin at concentration of 10-6 mol/L induced the strongest AMPKa expression (P<0.01). Intervention of HepG2 cells with leptin for 24 h increased the phosphorylation level of AMPKa gradually in a dose-dependent manner (P<0.01). The effect of leptin on the increase in the protein expression of p-AMPKa was also in a time-dependent manner (P<0.01). After intervention with different concentrations of leptin for 24 h, the protein expression of BSEP in the HepG2 cells was gradually increased by the stimulation of leptin in a concentration- and time-dependent manner (P<0.01). Compared with NC group, the protein expression of BSEP in 10-6 mol/L leptin group and 10-6 mol/L leptin+10 μmol/L compound C group was increased at 72 h (P<0.01), and that in 10-6 mol/L leptin+10 μmol/L compound C group was lower than that in 10-6 mol/L leptin group at 72 h (P<0.01). CONCLUSION: Leptin promotes the protein expression of BSEP in HepG2 cells by leptin-AMPK-BSEP signaling pathway. Leptin promotes the increases in AMPKa protein and the level of phosphorylation of AMPKa in HepG2 cells. 相似文献
9.
AIM: To investigate the mechanism that insulin-like growth factor binding protein 7 (IGFBP7) inhibits proliferation of human breast cancer cell line MCF-7. METHODS: Plasmid pCMV6-IGFBP7 or empty plasmid was transfected into MCF-7 cells. The expression of IGFBP7 in MCF-7 cells after transfection was detected by Western blotting. The effects of IGFBP7 on the colony-forming efficiency and the cell cycle were studied by soft agar colony formation assay and flow cytometry,respectively. The effects of IGFBP7 on the expression of ERK1/2, p-ERK1/2, cyclin D1, CDK4, cyclin E, CDK2, p21CIP1/WAF1, p27KIP1, p53, Rb and p-Rb in MCF-7 cells were detected by Western blotting. RESULTS: Only the transfectant of pCMV6-IGFBP7 expressed IGFBP7. IGFBP7 remarkably reduced colony-forming efficiency (P<0.01) and G0/G1 arrest (P<0.01), inhibited phosphorylation of ERK1/2 (P<0.01), down-regulated cyclin D1 and cyclin E (P<0.01), up-regulated p27KIP1, p21CIP1/WAF1 and p53 (P<0.01), and inhibited phosphorylation of Rb (P<0.01) in MCF-7 cells. PD98059, an inhibitor of MEK1 and MEK2, imitated part of the tumor-suppressing activity of IGFBP7. CONCLUSION: IGFBP7 inhibits the proliferation of human breast cancer cell line MCF-7 by down-regulating cyclin D1 and cyclin E, up-regulating p27KIP1, p21CIP1/WAF1 and p53 and inhibiting phosphorylation of Rb. ERK1/2 signaling pathway might be involved in the regulation of cyclin D1 and p27KIP1 by IGFBP7. 相似文献
10.
EGF in mouse neurons LI Juan WANG Li CHEN Rong LIU Xiao-yan MEI Zhi-qiang HE Tao 《园艺学报》2011,27(4):779-782
AIM: To explore the mechanism of signaling transduction and cross talk between cholecystokinin octapeptide (CCK8) and epidermal growth factor (EGF) in mouse neurons and to observe the effect of CCK8 in coordination with EGF on neuron growth and cell viability. METHODS: For determining which kind of CCK receptor mediated the phosphorylation of EGF receptor, the cultured neurons were randomly divided into control group, CCK8 stimulation group, CCKA receptor antagonist group, CCKB receptor antagonist group, and CCKA+CCKB receptor antagonist group. Control and stimulation groups were stimulated with DMEM and CCK8 (10-7 mol/L) for 5 min, respectively, while antagonist groups were pre-incubated with different types of receptor antagonists (10-8 mol/L) for 10 min and followed by stimulating the neurons with CCK8. For observing the effect of CCK8 and EGF on the phosphorylation of EGFR in neurons and on neuron growth and cell viability, the cultured neurons were randomly divided into control group, CCK8 stimulation group, EGF stimulation group and CCK8+EGF stimulation group, which were stimulated with DMEM, CCK8 (10-7 mol/L), EGF (40 μg/L) and CCK8+EGF for 5 min, respectively. Reactions were terminated by freezing the neurons in liquid nitrogen and the phosphorylated EGFR was detected by Western blotting. Meanwhile, the viability of the neurons was observed by MTT method after stimulated for 24 h, 48 h, 72 h and 96 h. RESULTS: The phosphorylation levels of EGFR were decreased in the neurons treated with either of the two CCK receptor antagonists, and more obvious decrease was observed when the two CCK receptor antagonists were used in combination. Compared with control group, the phosphorylation levels of EGFR in the neurons were significantly increased(P<0.05) after stimulated with CCK8 or EGF, and the increase was more remarkable in CCK8+EGF stimulation group. CCK8 or EGF improved the viability and prolonged the life span of the neuron, and synergism of these two reagents was observed. CONCLUSION: Both CCKA and CCKB receptors are involved in the phosphorylation of EGFR in the neurons stimulated by CCK8, and the type A receptor may play a more important role. There is cross-talk between CCK8 and EGF signaling pathways in neurons. The signaling cross-talk between CCK8 and EGF may be the underlying molecular mechanism responsible for the synergistic effect on the neuron growth and viability in vitro. 相似文献
11.
AIM: To investigate the effect of interleukin-2(IL-2) on the intracellular calcium in electrically stimulated adult rat ventricular myocytes during anoxia and reoxygenation. METHODS: The isolated cardiac ventricular myocytes were exposed to 5 min anoxia followed by 10 min reoxygenation. Chemical anoxia was introduced by Krebs-Henseleit(K-H) solution containing 10-3 mol/L sodium dithionite. The spectrofluorometric method was used to verify intracellular calcium transient with fura-2/AM as calcium fluorescence probe. RESULTS: It was shown that during anoxia, the amplitude of Ca2+ transient was decreased, diastolic [Ca2+]i, time to peak and time to relaxation of Ca2+ transient were increased. All the parameters were got back but did not returned to the pre-anoxia level during reoxygenation. IL-2 at 2×105 U/L administrated during anoxia aggravated the effect of rexoxygenation on [Ca2+]i transient. Pretreatment with a specific κ opioid antagonist, nor-BNI(10-8 mol/L), abolished the effect induced by IL-2 during anoxia on the [Ca2+]i transients, whereas specific δ opioid antagonist, naltrindole(10-6 mol/L), did not cancel the effect. CONCLUSION: It is concluded that administration of IL-2 during anoxia aggravated the effect of reoxygenation on the [Ca2+]i transients of isolated ventricular myocytes, which was mediated by cardiac κ opioid receptor pathway. 相似文献
12.
HU Jing-jing ZHANG Yu-jie LI Rong-qiao LIANG Tai-gang YANG Cai-hong LI Qing-shan 《园艺学报》2018,34(10):1778-1783
AIM: To investigate the effects of Rho-associated kinase (ROCK) and protein kinase C (PKC) on the relaxation of isolated rat aortic rings induced by nifedipine and the mechanisms. METHODS: The changes of tension in vascular rings induced by nifedipine under the basic condition and pre-contracted by norepinephrine (NE, 10-6 mol/L) or KCl (60 mmol/L) were observed. The effects of ROCK and PKC on the vasodilation induced by nifedipine were studied using the vascular ring perfusion device. RESULTS: Nifedipine (10-10 mol/L, 10-9 mol/L, 10-8 mol/L, 10-7 mol/L, 10-6 mol/L and 10-5 mol/L) had no significant relaxation effect on isolated aortic rings under basic condition. Nifedipine induced dose-dependent relaxation in both endothelium-intact and endothelium-denuded aortic rings pre-contracted by 10-6 mol/L NE and 60 mmol/L KCl (P<0.05). No obvious difference between endothelium-intact group and endothelium-denuded group was observed. After incubation of the PKC inhibitor staurosporine (STA, 10-8 mol/L) and PKC agonist phorbol 12-myristate 13-acetate (PMA, 10-7 mol/L), STA increased the relaxation induced by nifedipine, while PMA reduced the effect of nifedipine on blood vessels (P<0.05). After the incubation of the ROCK inhibitor fasudil (10-6 mol/L) and ROCK agonist angiotensin Ⅱ (Ang-Ⅱ, 10-9 mol/L), fasudil increased the relaxation induced by nifedipine, while Ang-Ⅱ reduced the effect of nifedipine on blood vessels (P<0.05). The relaxation induced by nifedipine was not statistically inhibited by BaCl2 (10-4 mol/L), tetraethylammonium (10-3 mol/L), glibenclamide (10-5 mol/L) and 4-aminopyridine (10-3 mol/L). In calcium-free and high-potassium solution, pre-treatment with nifedipine (10-9 mol/L, 5×10-8 mol/L and 10-6 mol/L) inhibited calcium-induced contraction of the aortic rings (P<0.05). However, nifedipine pre-treatment did not affect the contraction induced by NE in Ca2+-free medium. CONCLUSION: Nifedipine exhibits vasodilatation effect in a dose-dependent manner and the vasodilatation activity is endothelium-independent. The vasodilatation effect of nifedipine may be related to the inhibition of extracellular calcium influx, and inhibition of PKC and ROCK enhances the vasodilatation effect of nifedipine. 相似文献
13.
ZHOU Zhen-hai LI You-ji CHEN Yun-xian LI Xiao-ying YU Xue-qing LI Juan LUO Shao-kai YUAN Yao-guang 《园艺学报》2003,19(9):1257-1260
AIM:To study the effect of Bene Jones protein (BJP) from multiple myeloma(MM) patient and TGF-β1 on cultured renal proximal tubular cell(PTC) proliferation.METHODS:[H3]TdR incorporation was used to study the effect of λBJP and TGF-β1 on cultured rat NRK.52E PTC proliferation, the expression of TGF-β1 in the supernatant of PTC cultured with BJP was assessed with ELISA.RESULTS:① [H3]TdR incorporation of PTC was inhibited by BJP in a dose-dependent manner, when co-cultured with 100-800 μmol/L BJP and 2.0 μg/L TGF-β1, the [H3]TdR incorporation was lower than that of BJP alone, especially when BJP≥400 μmol/L;②The expression of TGF-β1 in the supernatant of PTC cultured with BJP was increased, especially when BJP≥400 μmol/L(P＜0.05);③ The [H3]TdR incorporation of PTC was also inhibited by exogenous TGF-β1 in a dose-dependent manner.CONCLUSION:λBJP has antiproliferative effect on rat PTC in vitro, The effect is related with stimulating the PTC to produce excessive TGF-β1, which also has antiproliferative effect on PTC in some degree. 相似文献
14.
AIM: To investigate the possibility that epidermal growth factor receptor pathway participates in the growth promotion by growth hormone (GH) of growth plate chondrocytes cultured in vitro from adolescent rats treated with gonadotropin-releasing hormone analogue (GnRHa). METHODS: The chondrocytes from tibial growth plate of 5-8 female Sprague-Dawley (SD) rats treated with GnRHa were cultured in monolayer. Specific pharmacological inhibitor of Janus kinase (JAK2 tyrphostin AG490, 1, 10, 100 nmol/L), EGFR kinase inhibitor AG1478 (0.1, 1, 10 nmol/L) and neutralizing antibodies against EGF (0.1, 1, 10 mg/L) were added before GH stimulation. The proliferation of chondrocytes was investigated by the methods of MTT and immunohistochemical staining for PCNA. Phosphorylations of ERK1/2 and EGFR were detected by Western blotting. RESULTS: GH enhanced the proliferation of chondrocytes and the levels of ERK1/2 and EGFR phosphorylation in a dose dependent manner. The effect peaked at the concentration of 100 μg/L. Pretreatment with tyrphostin AG490 and AG1478 almost completely inhibited the proliferation of chondrocytes and phosphorylation of ERK1/2 and EGFR by GH. However, the neutralizing antibodies against EGF only partially inhibited the effects of GH.CONCLUSION: GH achieves its direct effect on the promotion of cell proliferation by the activation of JAK2 pathway and the downstream end of MAPK-ERK signaling molecules. The promotion of cell proliferation can be mediated by activation of EGFR pathway. The results suggest that there is signaling cross-talk between GH and EGF-EGFR pathway. 相似文献
15.
AIM: To investigate whether leukotriene D4(LTD4) would stimulates proliferation of cultured human airway smooth muscle (ASMC). METHOD: Human ASMC were isolated and subcultured, varying concentration of LTD4 were added to the media. Cell counts were obtained, -thymidine([3H]-TdR) incorporation and inositol 1, 4, 5-trisphosphate (IP3) accumulation were measured. RESULTS: LTD4(0.1nmol·L-1~10 nmol·L-1) increased cell number and also increased incorporation of[3H]-TdR and accumulation of IP3 in a concentration dependent manner(P＜0.01). The latter response was blocked by phospholipase C inhibition with neomycin (1 μmoL·L-1(P＜0.01). However, neomycin had no effect on the promitogenic action of LTD4. CONCLUSION: LTD4 stimulates proliferation of cultured human ASMC and may play a role in airway remodeling of asthma. 相似文献
16.
AIM: To study the effects of Chinese herbal monomer naringin (NG) on the MAPK signal pathway in bone marrow mesenchymal stem cells (MSCs) derived from SD rats during the differentiation into osteoblasts in vitro . METHODS: The changes of evaluating indicators alkaline phosphatase (ALP), bone gla protein (BGP) and type I collagen (Col I) in MSCs were observed under the conditions of normal, adding p38 pathway inhibitor SB203580, adding extracellular signal-regulated kinase (ERK) pathway inhibitor PD98059, adding c-Jun N-terminal kinase (JNK) pathway inhibitor SP600125, and adding SB203580, PD98059 and SP600125 together. The protein phosphorylation of p38, ERK1/2 and JNK was measured by Western blotting. The mRNA expression levels of transforming growth factor beta 1 (TGF-β1), bone morphogenetic protein 2 (BMP-2) and core binding factor α1 (Cbfα1) were measured by fluorescence quantitative PCR. RESULTS: The most effective concentration of NG to promote the differentiation of MSCs into osteoblasts was 10-7 mol/L. The highest expression levels of both ALP and BGP were observed in NG group (P<0.05), while the expression of Col I did not reveal significant difference (P>0.05). Compared with NG group, the expression levels of ALP, BGP and Col I decreased differently after adding different inhibitors. Compared with control group, the protein phosphorylation of JNK was increased (P<0.05), and the phosphorylation of p38 was decreased (P<0.05), while the phosphorylation of ERK1/2 did not reveal significant difference (P>0.05) in NG group. Compared with NG group, the protein phosphorylation of p38, ERK1/2 and JNK showed fluctuation with some increasing and others decreasing. Compared with control group, the expression of BMP-2 was increased (P<0.05), and the expression of Cbfα1 was decreased(P<0.05), while the expression of TGF-β1 did not reveal significant difference (P>0.05) in NG group. Compared with NG group, the mRNA expression levels of TGF-β1, BMP-2 and Cbfα1 decreased differently after adding different inhibitors. CONCLUSION: Activation of ERK/JNK signaling and up-regulation of BMP-2 expression may be the main mechanism of NG to promote the differentiation of MSCs into osteoblasts. NG has strong impact on p38 pathway to improve the expression of BMP-2 in MSCs. 相似文献
17.
AIM:To evaluate effects of inhaled nitric oxide(iNO) on adhesion molecule CD11b expression on lung neutrophils in experimental meconium aspiration syndrome(MAS) rabbits treated with conventional mechanical ventilation under room air or 100%O2. METHODS:Animals were randomly allocated to 8 groups(n=48) of 6 each: two MAS model groups(under room air or 100%O2 without iNO treatment), 6 treatment groups were treated with continuous NO inhalation at a dose of 0.2×10-6mol/L, 0.33×10-6mol/L or 0.67×10-6mol/L respectively for 12 hours under room air or 100%O2. Mean systemic arterial pressure(SAP) and methemoglobin (MeHb) were performed at basement time, 0, 2, 4, 12 hours. Expression of CD11b on neutrophils in the bronchoalveolar lavage fluid(BALF) was detected with flow cytometry. RESULTS:SAP, MeHb at different time among different groups were within the normal scale. CD11b expression on the neutrophils in the BALF significantly decreased in groups of inhalation 0.33×10-6 mol/L or 0.67×10-6 mol/L NO, compared with the two MAS model groups. (x±s: under 21%O2, 0.33×10-6 mol/L NO, 121±20 υs 392±204; 0.67×10-6 mol/L NO, 112±30 υs 392±204;under 100%O2, 0.33×10-6 mol/L NO, 113±24υs293±65; 0.67×10-6 mol/L 102±114 υs293±65, P<0.05). 0.2×10-6mol/L NO inhalation did no effect on CD11b expression. (x±s:21%O2, 190±101 υs 392±204; 100%O2, 222±85 υs 293±65; P>0.05). No statistic difference was observed between groups inhaled 0.33×10-6 mol/L NO and 0.67×10-6mol/L NO. CONCLUSION:0.33×10-6 mol/L or 0.67×10-6 mol/L NO inhalation down-regulated the CD11b expression on the neutrophils in BALF to reduce the sequestration of neutrophils in rabbit lung. 相似文献
18.
AIM:To study the effect of insulin on proliferation and hypertrophy of cardiac myocytes and its role in the induction of cardiac hypertrophy. METHODS:1. The neonatal rat cardiac myocytes and cardiac fibroblasts were cultured respectively and identified with light microscopy, electron microscopy and immunocytochemistry. 2. Cell proliferation was measured with cell number, metabolic activity and DNA synthesis (with WST-1, BrdU enzyme-linked immunosorbent assay ) and the percentage of S+G2+M in cell cycle (by flow cytometry ). 3.Cell hypertrophy was evaluated by cell protein content (Coomassie Briliant Blue's method). RESULTS:1. The cultured cells showed the characteristic of cardiac myocytes and cardiac fibroblasts, respectively. 2. After being treated with insulin, the cell number, absorbance of BrdU incorporation and WST-1 cleavage products and the percentage of S+G2+M of cardiac fibroblasts increased significantly (P＜0.01 orP＜0.05), while the above parameters of cardiac myocytes remained unchanged (P＞0.05). 3. Protein content of cardiac myocytes increased significantly in a dose-dependent manner (P＜0.01 orP＜0.05) in insulin treated groups (10-10 mol/L-10-7 mol/L). CONCLUSION:Insulin promoted cardiac fibroblast proliferation and increased myocytes protein content(induced myocyte hypertrophy)in vitroand may play an important role in pathogenesis of cardiac hypertrophyin vivo. 相似文献
19.
AIM: To study the effects of cyproheptadine (Cyp) and anisodamine (Ani) on the changes of intracellular free Ca2+ concentration ([Ca2+]i) induced by tumor necrosis factor (TNFα) in single endothelial cells, and to explore the mechanisms of TNFα mediated shock and antishock actions of Cyp and Ani. METHODS: Human umbilical vein endothelial cell strains (ECV304) were seed in 35 mm tissue culture dish with 2 mL DMEM culture medium. The cultured cells were loaded by Fluo-3/AM. The spatial distribution and the dynamic changes of [Ca2+]i in single endothelial cell was determined by laser scanning confocal microscopy (LSCM). RESULTS: [Ca2+]i in single endothelial cell after stimulation of TNFα rapidly increased in a dose-dependent manner and approached the peak value within 60 seconds, afterwards, decreased and kept above the basal level. The confocal scanning image showed that [Ca2+]i elevation was more obvious in nuclear than in cytoplasma, and decreased slowly. Cyp (3×10-5, 6×10-5 mol/L) and Ani (2×10-5, 4×10-5 mol·L-1) markedly inhibited TNFα (1.2×10-9 mol·L-1)-induced [Ca2+]i elevation. CONCLUSIONS: TNFα markedly induces elevation of [Ca2+]i in single endothelial cell, it may be an important mechanism of TNFα-induced shock and tissue injury. Cyp and Ani obviously suppress TNFα-induced [Ca2+]i elevation, which probably is one of the mechanisms of their antishock effects. 相似文献
20.
JIANG Ping Polat·Tuersun LI Jun-hong Xuehereti·Enayeti NIE Yong-mei Aynur·Galilee ZHANG Shun-jie SHEN Yue-liang 《园艺学报》2010,26(12):2321-2326
AIM: To elucidate the effect of caveolin-1 on the down-regulation of LPS-induced monocyte chemotactic protein 1 (MCP-1) by 17β-estradiol (E2) in vascular smooth muscle cells (VSMCs).METHODS: The primary-cultured VSMCs were exposed to E2 at concentrations of 10-9-10-6 mol/L. LPS-induced MCP-1 production was assayed by ELISA. The protein expression of caveolin-1 was determined by Western blotting and was silenced by β-methyl cyclodextrin(β-MCD) or caveolin-1 specific siRNA. RESULTS: LPS significantly enhanced MCP-1 production. E2 at concentrations of 10-9-10-6 mol/L inhibited LPS-induced MCP-1 production. The use of caveolin-1 inhibitor β-MCD or silencing the protein expression of caveolin-1 by specific siRNA largely impaired LPS-enhanced MCP-1 production, while E2 markedly inhibited caveolin-1 expression. CONCLUSION: Inhibition of LPS-induced MCP-1 production by E2 is related to the suppression of caveolin-1. 相似文献