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1.
AIM: To investigate the effect of maxadilan, which specifically activates pituitary adenylate cyclase-activating polypeptide type I receptor (PAC1 receptor), on the proliferation, apoptosis and differentiation potential of human adipose-derived stem cells (ASCs). METHODS: ASCs from human adipose tissue were isolated by enzymatic digestion and cultured. ASCs were confirmed by the analysis of the markers for cell phenotypes by flow cytometry (FCM) and adipogenic/osteogenic induction. The effect of maxadilan on ASCs viability was analyzed by CCK-8 assay and FCM. ASCs were irradiated by ultraviolet C (UVC) at 254 nm and the absorbance of apoptotic ASCs induced by various doses of UVC was measured by CCK-8 assay. ASCs were exposed to 702 J/m2 UVC for 24 h to induce apoptosis. The effect of maxadilan on ASC apoptosis was analyzed by FCM and the determination of caspase 3 and caspase 9 levels. RESULTS: Adipose-derived stem cells were confirmed by the detection of the positive expression of cell phenotypes including CD29, CD44, CD59 and CD105 by FCM. The data of CCK-8 assay revealed that ASCs treated with maxadilan (80 nmol/L) had the strongest ability of proliferation. The data of FCM also demonstrated that the addition of 80 nmol/L maxadilan to ASCs in experimental group markedly improved the proliferation capacity of the cells compared with control group (P<0.05). The apoptosis of ASCs exposed to 702 J/m2 UVC was dramatically inhibited by the treatment with maxadilan (80 nmol/L). Such process involved the caspase signaling pathway including caspase 3 and caspase 9. There was statistical significance (P<0.05) between experiment group (ASCs irradiated by UVC and supplemented with maxadilan) and control group (ASCs only irradiated by UVC). Meanwhile, adipogenic and osteogenic differentiation potentials were both positive in experiment group and control group. CONCLUSION: Maxadilan promotes proliferation and inhibits apoptosis of the ASCs. The differentiation potential of ASCs toward adipogenic and osteogenic lineages wouldn't be altered by maxadilan. Maxadilan would benefit to growth and expansion of ASCs in vitro.  相似文献   

2.
AIM: To investigate the effect of insulin at different concentrations on the expression of sterol regulatory element binding protein-1 (SREBP-1), fat acid synthase (FAS) and lipid droplet formation in human renal proximal tubular epithelial cell line (HKC). METHODS: HKC cells were treated with insulin at concentrations of 0 nmol/L, 1 nmol/L, 10 nmol/L, 100 nmol/L and 200 nmol/L respectively for 6 h. The analysis of SREBP-1 and FAS mRNA was performed by RT-PCR and the protein level of SREBP-1 was detected by Western blotting and immunocytochemistry. Oil red O staining was used to determine the cellular lipid droplet formation. RESULTS: Compared to HKC cells under the condition without insulin treatment (0 nmol/L group), the expression of SREBP-1 and FAS mRNA was significantly increased in HKC cells treated with insulin at concentrations of 10 nmol/L, 100 nmol/L or 200 nmol/L. Furthermore, the highest expression of SREBP-1 and FAS mRNA was observed in 100 nmol/L group. The SREBP-1 protein was located in the plasma of the HKC cells and was significantly upregulated in the cells treated with insulin at concentrations of 10 nmol/L, 100 nmol/L or 200 nmol/L. The results of Western blotting showed that the precursor and mature segments of SREBP-1 protein were increased in the cells of 10 nmol/L group, 100 nmol/L group and 200 nmol/L group, and those in 100 nmol/L group were the highest. The result of oil red O staining showed that the markedly deposited lipid droplet was only observed in 100 nmol/L group. CONCLUSION: The results suggest that insulin at high concentration up-regulates SREBP-1 and FAS, resulting in the formation and deposit of cellular lipid droplet in HKC cells, which may play an important role in the pathogenesis of renal lipid accumulation in metabolism syndrome.  相似文献   

3.
WANG Jing-wen 《园艺学报》2010,26(11):2256-2259
AIM: To investigate the effects of adenosine A1 receptor antagonist DPCPX on the release of cerebral neuronal lactate dehydrogenase (LDH), the activity of calcineurin (CaN) and acetylcholinesterase (AChE), and the level of extracellular amino acid after hypoxia and reoxygenation (H/R).METHODS: Primary cultured rat cerebral cortical neurons were used to establish an H/R injury model. Different concentrations of DPCPX (the final concentrations were as follows: 0, 25, 50 and 100 nmol/L) were added at the same time of hypoxia treatment for 8 h, 12 h or 24 h,followed by reoxygenation for 24 h. The LDH release from the neurons was measured. The effects of DPCPX (100 nmol/L) on the activity of CaN and AChE, and the level of extracellular amino acid in neurons treated with hypoxia for 12 h followed by reoxygenation were observed. RESULTS: Compared to the cells in control groups, the neurons treated with 100 nmol/L DPCPX and exposed to hypoxia for 12 h followed by reoxygenation, showed significantly higher LDH release, higher activity of CaN and AChE, and lower level of extracellular γ-aminobutyric acid.CONCLUSION: These results suggest that DPCPX increases the LDH release and the activity of CaN and AChE, decreases the level of extracellular γ-aminobutyric acid in neurons with H/R.  相似文献   

4.
AIM:To study the effects of gastrin on the migration and invasion of gastric cancer cells in vitro. METHODS:The migration and invasion of gastric cancer AGS and SGC-7901 cells after treated with gastrin at concentrations of 10 nmol/L and 100 nmol/L were studied by wound-healing assay and Transwell migration and invasion assay. The cell proliferation was analyzed by MTT colorimetric method. The concentration of matrix metalloproteinase 2 (MMP-2) in the culture medium was detected by ELISA. The AGS and SGC-7901 cells without treating with gastrin served as control cells. RESULTS:Compared with the control cells, the migration and invasion of AGS cells and SGC-7901 cells were significantly increased after treated with gastrin at concentrations of 10 nmol/L and 100 nmol/L. In control, 10 nmol/L gastrin and 100 nmol/L gastrin groups, the mean numbers of the migrating cells were 56.0, 88.1 and 106.4/view in AGS cells and 52.8, 91.0 and 113.3/view in SGC-7901 cells, and the mean numbers of the invasive cells were 78.4, 118.7 and 141.6/view in AGS cells and 87.3, 124.6 and 147.4/view in SGC-7901 cells, respectively. The numbers of the migrating cells and invasive cells in 100 nmol/L gastrin group were higher than those in 10 nmol/L gastrin group. The cell proliferation rate and the concentration of MMP-2 in the culture medium in gastrin treatment groups were higher than those in control group. CONCLUSION:Gastrin promotes the migration and invasion of gastric cancer cells in a dose-dependent manner by increasing the MMP-2 secretion, which may be the key mechanism in the proliferation, invasion and metastasis of the cancer cells in vivo.  相似文献   

5.
AIM: To investigate the protective effect of sodium selenite (Na2SeO3) on human keratinocytes under ultraviolet-B (UVB) irradiation. METHODS: The cultured HaCaT cells were divided into 4 groups: (1) normal control group; (2) Na2SeO3 group: pretreated with Na2SeO3 at doses of 10 nmol/L, 50 nmol/L, 100 nmol/L, 200 nmol/L and 1 μmol/L for 24 h; (3) UVB group: irradiated with UVB at doses of 300, 600 and 900 J/m2 ; (4) Na2SeO3+UVB group: after pretreated with Na2SeO3 for 24 h, irradiated with UVB at doses of 300, 600 and 900 J/m2 . The cell proliferation was detected by MTT assay. The apoptotic rates of HaCaT cells treated with UVB at dose of 300 J/m2 were assessed by flow cytometry. RESULTS: Compared with normal control group, the cell proliferation activity in UVB group decreased significantly (P<0.05). The cell activity was inversely correlated with the irradiation intensity. No significant difference of the cell activity between Na2SeO3 group and normal control group was observed. The cell proliferation in Na2SeO3+UVB group was higher than that in UVB group significantly (P<0.05). Na2SeO3 at concentration of 100 nmol/L showed the strongest activity to promote cell proliferation. After 300 J/m2 UVB irradiation, the apoptotic rate in Na2SeO3+UVB group decreased significantly (P<0.05) compared with UVB group. The inhibitory effect of Na2SeO3 at concentration of 100 nmol/L on apoptosis was the strongest.CONCLUSION: The damage of human keratinocytes by UVB irradiation is in a dose-dependent manner. The photoprotection performance of Na2SeO3 reduces the damage of human keratinocytes induced by UVB irradiation.  相似文献   

6.
AIM: To investigate the influence of C*HSDGIC* (CHC), a cyclopeptide from the cyclization of with disulfide, on the proliferation and apoptosis of cultured human retinal pigment epithelial (RPE) cells induced by ultraviolet B(UVB). METHODS: The expression of PACAP type 1 (PAC1) receptor in human RPE cells was identified by Western blotting. The cells were exposed to UVB irradiation and cultured in fresh medium with or without gradient concentrations (1 nmol/L to 1 mmol/L) of CHC. The viability of the cells was determined by CCK-8 assay. The early apoptosis of the cells was detected by flow cytometry with annexin V and propidium iodide staining.The mitochondrial menbrane potential was detected by flow cytometry with JC-1 staining. RESULTS: The PAC1 receptor in human RPE cells was identified by Western blotting. The best results of CHC on the proliferation and anti-apoptosis of human RPE cells were achieved at the concentration of 100 μmol/L, which increased the viability by (34.23±3.39)% and (20.10±1.48)%, respectively. The percentage of apoptotic cells was decreased by (5.63±1.49)% with CHC treatment (100 μmol/L) after UVB irradiation,and the percentage of mitochondrium-depolarizing cells was decreased by (5.2±0.5)%. CONCLUSION: PAC1 receptor exists in human RPE cells. C*HSDGIC* increases the viability of RPE cells and attenuates UVB-induced apoptosis.  相似文献   

7.
AIM: To study the effects of camptothecin (CPT) on the activation, proliferation and cell-cycle distribution of the mouse T lymphocytes stimulated by concanvalin A (ConA) in vitro. METHODS: A model of T cell activation and proliferation was established by stimulated the cells with Con A. T cells were treated with different concentrations of CPT. The expression of CD69, the early marker of CD3+ T cell activation, was measured by FACS. The proliferation index was determined by carboxyl fluorescin diacetate succinmidyl ester by flow cytometry. The cell-cycle distribution was analyzed by propidium iodide staining. RESULTS: After stimulation with Con A for 6 h, the activation rate of CD69+ T cell in Con A group was (58.88±0.55)%. The percentages of CD69 positive cells were (55.48±0.98)%, (54.67±1.05)%, (50.40±0.82)%, (42.47±1.32)%, correspond to the treatments with different concentrations of CPT (10 nmol/L, 20 nmol/L, 50 nmol/L, 100 nmol/L), respectively. After 48 h treatment with Con A, the proliferation index in different concentrations of CPT treatment (10 nmol/L, 20 nmol/L, 50 nmol/L and 100 nmol/L) exerted a definite inhibitory effect on the proliferation (P<0.01). Moreover, the cell-cycle distribution analysis showed that apoptosis peak was observed in different concentrations of CPT treatment after 48 h cultured with Con A. CONCLUSION: CPT significantly inhibits the early stages of the Con A-induced T cell activation and proliferation, and detents the T lymphocytes in G0/G1 phase.  相似文献   

8.
AIM: To study the effect of estradiol (E2) on the viability of mesenchymal stem cells (MSCs) derived from the decidua of the placenta by regulating the expression of microRNA-16 (miR-16). METHODS: The concentration of E2 in the peripheral blood of normal pregnant women and the patients with severe preeclampsia (PE) was measured. The effects of E2 at different concentrations on the viability of MSCs were analyzed. The effect of E2 at different concentrations on the expression of miR-16 in the MSCs was detected, and which estrogen receptor (ER) mediated the regulatory effect of E2 on miR-16 expression was determined. RESULTS: The concentration of E2 in peripheral blood of the patients with severe PE was significantly decreased (P<0.01). After treatment with E2 at 5, 10 and 100 nmol/L for 48 h, the viability of MSCs was increased (P<0.05). The expression level of miR-16 was down-regulated in the MSCs treated with E2 at 5, 10 and 100 nmol/L for 12 h. After treatment with E2 at 10 nmol/L for different time (0 h, 3 h, 6 h, 12 h and 24 h), the expression level of miR-16 in the MSCs showed a clear time-dependent downward trend. E2 significantly promoted the viability of MSCs, and the cell viability was significantly reversed after miR-16 pretreatment. Pretreatment with estrogen receptor antagonists ICI 182780 and tamoxifen for 6 h attenuated the inhibitory effect of E2 on miR-16 expression. Only ERα agonist propyl pyrazole triol significantly inhibited the expression of miR-16 in MSCs but ERβ agonist diarylpropionitrile did not. CONCLUSION: E2 promotes the growth of decidua-derived MSCs by inhibiting miR-16 via ERα.  相似文献   

9.
AIM: To investigate the neuroprotective effect of progesterone against adenosine triphosphate (ATP)-injured human neuroblastoma SH-SY5Y cells.METHODS: The SH-SY5Y cells in the logarithmic phase were divided into different groups according to the progesterone and ATP concentrations. The cell viability was measured by CCK-8 assay. The membrane permeability was detected using fluorescent dye YO-PRO-1. Cytosolic Ca2+ concentration was measured with fluorescent dye Fluo-3/AM. The expression of purinergic P2X7 receptor was assessed by Western blot.RESULTS: The viability of the SH-SY5Y cells was significantly decreased (P<0.05) and YO-PRO-1 uptake was obviously increased (P<0.05) in a concentration-dependent manner compared with control group when SH-SY5Y cells were treated with ATP at 1, 3, 5 and 7 mmol/L for 2 h. The viability reduction of the SH-SY5Y cells induced by ATP was obviously counteracted by treatment with progesterone at 3, 10 and 30 nmol/L for 30 min (P<0.05) as compared with ATP group. YO-PRO-1 fluorescence enhancement induced by ATP in SH-SY5Y cells was significantly reduced (P<0.05) by progesterone (30 nmol/L) or P2X7 receptor antagonist KN-62 (500 nmol/L) pretreatment for 30 min, and no obvious difference between treatments with progesterone and KN-62 was observed. Cytosolic Ca2+ fluorescence intensity in normal group was a little, but that in ATP group was increased (P<0.05). Progesterone or KN-62 pretreatment significantly decreased the cytosolic fluorescence intensity of Ca2+ induced by ATP (P<0.05). However, no obvious difference between treatments with progesterone and KN-62 was found. The expression of P2X7 receptor in ATP group was significantly higher than that in control group (P<0.05), and progesterone inhibited ATP-induced P2X7 receptor expression (P<0.05).CONCLUSION: Progesterone inhibits P2X7 receptor expression, membrane pore formation, intracellular Ca2+ increase and cell death induced by ATP, so progesterone may protect SH-SY5Y cells against ATP-induced injuries.  相似文献   

10.
AIM:To investigate whether Ligustrazine(LTZ) has an effect on the changes of protein kinase C(PKC) signaling pathway induced by inflammatory mediators involved in asthma in normal human peripheral blood lymphocytes (PBL).METHODS:10 mL peripheral venous blood was obtained from each of 63 health humans and treated as follows. The activities of PKC from cytosolic and membrane fractions in PBL were measured by -ATP-catalyzing assay, after PBL had been isolated and performed by following processes: (1) First: three groups treated with 5 g/L LTZ(n=6) or 5 μmol/L Ro31-8220 (n=6); Paired untreated PBL served as control of this group, as well as the negative controls of the following groups(n=6); (2)Second : three groups treated with 100 nmol/L Methacholine (Mch, n=5), 5 g/L LTZ+100nmol/L Mch(n=5)or 5 μmol/L Ro31-8220(a PKC inhibitor)+100 nmol/L Mch(n=5); (3)Third: three groups treated with 100 nmol/L histamine, 5 g/L LTZ+100 nmol/L histamine(n=5) or 5 μmol/L Ro31-8220+100nmol/L histamine(n=5); (4)Fourth: three groups treated respectively with 100nmol/L PMA(a PKC activator, n=5), 5 g/L LTZ+100nmol/L PMA(n=5) or 5 μmol/L Ro31-8220+100nmol/L PMA(n=5).RESULTS:(1)LTZ had no effect on the activities of PKC in inactive PBL in normal humans; (2) Methacholine or histamine resulted in an increase in membrane PKC activity of normal human PBL, which was partly suppressed by LTZ (all P<0.05); (3) PMA caused an increase in membrane PKC activity of normal human PBL, which was partly decreased by LTZ (all P<0.05).CONCLUSION:LTZ has an inhibitory effect on activation of PKC signaling pathway in PBL in normal humans induced by some inflammatory mediators involved in asthma, which may be one of the mechanisms that LTZ plays a role in the prevention and therapy of asthma.  相似文献   

11.
AIM To investigate the regulatory effect of retinoic acid X receptor (RXR) on autophagy induced by hypoxia/reoxygenation (H/R) in rat alveolar type Ⅱ epithelial cells (AEC Ⅱ) and its molecular mechanism. METHODS AEC Ⅱ were cultured in normoxia. The cells growing to logarithmic growth phase were randomly divided into 5 groups: (1) control (Con) group: cells were cultured for 30 h under normal operation; (2) H/R group: cells were cultured in hypoxia condition for 6 h and then in reoxygenation condition for 24 h; (3) DMSO group: cells were pretreated 1.5 h with medium containing less than 0.1% DMSO before modeling, and the rest were treated the same as the H/R group; (4) 9-cis-retinoic acid (9-RA) group: cells were pretreated for 1 h with 9-RA (100 nmol/L) before hypoxia; (5) HX531 group: cells were treated with 9-RA (100 nmol/L) for 0.5 h, then treatment with HX531 (2.5 μmol/L) for 1 h. CCK-8 assay was used to detect the cell viability. Immunofluorescence staining was used to observe the expression of RXRα. Transmission electron microscope was used to observe the changes of intracellular ultrastructure, and the mRNA expression of adenosine AMP-activated protein kinase (AMPK), beclin 1, LC3, mammalian target of rapamycin (mTOR) and P62 was detected by RT-PCR. Western blot was used to detected the protein levels of p-AMPK, beclin 1, LC3-Ⅱ, p-mTOR and P62. RESULTS Compared with Con group, the cell viability in H/R, DMSO, 9-RA and HX531 groups were significantly decreased. The mRNA expression of AMPK, beclin 1 and LC3 was significantly increased, and the protein levels of p-AMPK, beclin 1 and LC3-Ⅱ were also increased. The mRNA expression of mTOR and P62 was decreased, and the protein levels of p-mTOR and P62 were also decreased (P<0.05). The cell injury in 9-RA group was alleviated and autophagy level was significantly lower than that in H/R, DMSO and HX531 groups (P<0.05), and no significant difference among H/R, DMSO and HX531 groups was observed (P>0.05). CONCLUSION H/R induces autophagy of AEC Ⅱ. Activating RXR reduce the damage of AEC Ⅱ cells induced by H/R, and its mechanism may be related to the inhibition of autophagy.  相似文献   

12.
AIMTo investigate the roles of protein phosphatase 4 (PP4) in down-regulation of endothelial nitric oxide synthase (eNOS) Ser633 phosphorylation induced by palmitic acid (PA). METHODSHuman umbilical vein endothelial cells (HUVECs) were treated with PA at 25 μmol/L, 50 μmol/L, 100 μmol/L and 200μmol/L for 36 h, or treated with PA at 100 μmol/L for 12 h, 24 h, 36 h and 48 h. Protein phosphatase 2A (PP2A) family inhibitor fostriecin (FST, 20 nmol/L) or okadaic acid (OA, 5 nmol/L) was selected to pretreat the HUVECs for 30 min. Protein phosphatase 4 catalytic subunit (PP4c) siRNA or protein phosphatase 2A catalytic subunit (PP2Ac) siRNA was transfected into the HUVECs. The protein expression levels of of eNOS, PP4c and PP2Ac, as well as the level of eNOS Ser633 phosphorylation, were detected by Western blot. The intracellular nitric oxide (NO) content was measured by DAF-FM DA. RESULTS(1) Compared with control group, the levels of eNOS Ser633 phosphorylation were decreased in PA groups in which the HUVECs were treated with 25 μmol/L, 50 μmol/L, 100 μmol/L and 200 μmol/L PA for 36 h (P<0.05) and 100 μmol/L PA for 24 h, 36 h and 48 h (P<0.05). No significant difference in the level of total eNOS protein expression among all the groups was observed. (2) Compared with control group, both FST and OA pretreatment reversed the reduction of eNOS Ser633 phosphorylation (P<0.05) and the decrease in intracellular NO content (P<0.05) induced by PA. No significant difference in the level of total eNOS protein expression among all the groups was observed. (3) Compared with si-Control group, the PP4c protein expression was significantly reduced (P<0.05), while the level of eNOS Ser633 phosphorylation was significantly increased in si-PP4c group (P<0.05). Although the levels of PP2Ac protein expression declined significantly (P<0.05), the level of eNOS Ser633 phosphorylation remained unchanged in si-PP2Ac group. No significant differencein the level of total eNOS protein expression among all the groups was found. CONCLUSION PA significantly reduces the level of eNOS Ser633 phosphorylation and the content of NO in the HUVECs, which may be due to PA inducing the activation of the PP2A family member PP4 rather than PP2A.  相似文献   

13.
AIM: To investigate the influence and the mechanism of recombinant macrophage migration-inhibitory factor (rMIF) on fibroblasts. METHODS: Cultured human embryonic lung fibroblasts (MRC-5 cells) were divided into 2 groups: the cells in treatment group were treated with rMIF (25~100 μg/L) for 24 h or 48 h, and the control cells were without rMIF treatment. The mRNA expression of α-SMA was examined by RT-PCR. The protein level of α-SMA induced by rMIF was quantified by Western blotting. Half an hour before 100 μg/L rMIF challenge, Y27632 was added to the cells of 2 groups. After challenged for 48 h, the total RNA and protein were extracted,and the expression of α-SMA at mRNA and protein levels was determined by means of RT-PCR and Western blotting. After challenged by 100 μg/L rMIF for 6 h, 12 h, 24 h and 48 h, the cell total protein was extracted, and the protein level of α-SMA induced by rMIF was quantified by Western blotting. RESULTS: After stimulation for 24 h, rMIF did not increase the α-SMA mRNA synthesis compared with control. After stimulation for 48 h, rMIF significantly increased the expression of α-SMA mRNA and protein in a dose-dependent manner compared with control (r=0.697 and r=0.957, both P<0.01). Y27632 pretreatment prevented the increase (P<0.01). The amount of phosphorylated MYPT1 increased at 6 h (P<0.01), reached the maximum at 12 h (P<0.01), and decreased but still higher than the control at 24 h and 48 h (P<0.01). CONCLUSION: rMIF increases the α-SMA synthesis in MRC-5 cells and Rho-kinase regulates this process, suggesting that MIF may play important roles in the pathogenesis of airway remodeling.  相似文献   

14.
LI Jia-ying  FENG Lie 《园艺学报》2014,30(6):1088-1092
AIM:To investigate whether trichostatin A (TSA), a new revulsant,can induce mouse mesenchymal stem cells to differentiate into insulin-secreting cells and to explore the appropriate concentration of TSA. METHODS:The mesenchymal stem cell line from C57BL/6 mice was cultured in vitro and divided into 5 groups before treated with different concentrations of TSA, (group A: DMSO; group B~E: treated with 25 nmol/L, 50 nmol/L, 100 nmol/L and 200 nmol/L of TSA, respectively). After exposed to different cultured media for 10 d during the 2 stages, the cells were detected by the following methods: the insulin-secreting cells in each group were identified by dithizone staining and the results were calculated with immunohistochemical half quantitative analysis. The insulin secreted by insulin-secreting cells in each group was identified by immunofluorescence, and the mean fluorescence intensity of insulin was compared. The content of insulin in each group was quantified by ELISA. The appropriate concentration of TSA was determined according to the above results. RESULTS:TSA treatment for 10 d promoted the mouse bone marrow mesenchymal stem cells to differentiate into insulin-secreting cells which produced insulin. The immunohistochemistry and immunofluorescence imaging analysis of insulin-secreting cells showed that the insulin staining positive area, positive ratio, total density of insulin expression and mean fluorescence intensity of insulin in group B were significantly higher than those in the other TSA-treated groups. When the concentrations of TSA gradually increased, the content of insulin reduced accordingly. The content of insulin in group B was significantly higher than that in the other TSA-treated groups. CONCLUSION:TSA treatment for 10 d promotes bone marrow mesenchymal stem cells from C57BL/6 mice to differentiate into insulin-secreting cells and the appropriate concentration of TSA is 25 nmol/L.  相似文献   

15.
AIM:To study the role of ghrelin in cell protection by up-regulating heat shock protein 70 (HSP70) and inhibiting apoptosis induced by oxidative stress through extracellular regulated protein kinases 1/2 (ERK1/2) signaling pathway in the PC12 cells. METHODS:Sodium nitoprusside (SNP) was used to induce oxidative stress injury in the PC12 cells. The cultured PC12 cells were divided into SNP-injured group (incubated with SNP at 0.5 mmol/L for 6, 12, 18 and 24 h), ghrelin pretreatment group (ghrelin at 100 nmol/L was given 30 min before adding SNP); HSP70 inhibitor group (quercetin at 10 μmol/L was added 60 min before ghrelin treatment), ERK inhibitor group (ERK 1/2 inhibitor PD98059 was added 60 min before ghrelin treatment) and control group (added same amount of culture medium only). The apoptotic rate was detected by flow cytometry. The protein expression was determined by Western blot and immunocytochemistry. RESULTS:Compared with control group, the apoptotic rate of PC12 cells in SNP-injured group was significantly increased (P<0.05). Compared with SNP-injured group, ghrelin (100 nmol/L) pretreatment significantly inhibited SNP-induced apoptosis of PC12 cells (P<0.05), and significantly up-regulated the protein expression of HSP70 (P<0.05). Time-effect analysis showed that ghrelin had the most significant effect at 18 h after SNP injury. Quercetin, an inhibitor of HSP 70, significantly reduced the anti-apoptotic effect of ghrelin (P<0.05). Ghrelin pretreatment promoted the phosphorylation of ERK1/2. ERK1/2 inhibitor PD98059 significantly inhibited the effects of ghrelin on up-regulation of HSP70 expression (P<0.05). CONCLUSION:Ghrelin upregulates the expression of HSP70 and inhibits the apoptosis in the PC12 cells induced by oxidative stress by promoting the phosphorylation of ERK1/2.  相似文献   

16.
AIM: To investigate the effect of AG490 on the expression of VEGF and HIF-1α, and the capacity of invasion in human erythroleukemia (HEL) cells. METHODS: The HEL cells were treated with AG490 at different concentrations. The cell viability was detected by CCK-8 assay. The apoptosis was detected by Hoechst staining. The apoptosis and the cell cycle were analyzed by flow cytometry. The capacity of migration was evaluated by Transwell assay. The mRNA expression level of JAK2 was measured by RT-PCR. The protein levels of p-JAK2, VEGF and HIF-1α were determined by Western blot. RESULTS: The HEL cell viabilities were 88%, 75%, 48%, 10% and 0.12% after treated with AG490 at 20, 40, 60, 80 and 100 μmol/L for 48 h, respectively. The results of Hoechst staining showed that brilliant blue cells in 80 μmol/L AG490 group was significantly increased compared with control group for 48 h. The apoptosis rate of 80 μmol/L AG490 group was significantly increased compared with control group at 48 h after AG490 treatment. The number of membrane-permeating HEL cells in 20 μmol/L AG490 group at 24 h after AG490 treatment was significantly lower than that in control group (P<0.05). The mRNA level of JAK2 decreased in a concentration-dependent manner after the HEL cells were treated with different concentrations of AG490 for 48 h. The protein levels of p-JAK2, VEGF and HIF-1α were lower in AG490 treatment groups than those in control group (P<0.05). CONCLUSION: AG490 inhibits the expression of VEGF and HIF-1α in HEL cells by inhibiting JAK2 pathway.  相似文献   

17.
AIM: To investigate the effects of simvastatin on cigarette smoke extract (CSE)-induced expression levels of soluble endothelial cell protein C receptor (sEPCR) and membrane-associated endothelial cell protein C receptor (mEPCR ) in human umbilical vein endothelial cells (HUVECs). METHODS: Cultured HUVECs at passage 4 to 6 were randomly divided into control group, 5% CSE group, simvastatin groups and simvastatin+CSE groups. In simvastatin groups, HUVECs were incubated with simvastatin at the concentrations of 50, 100 and 200 μmol/L for 24 h. In simvastatin+CSE groups, the cells were treated with simvastatin at the concentrations of 50, 100 and 200 μmol/L for 2 h, and then exposed to CSE for 24 h. The protein level of sEPCR in the culture supernatants was measured by ELISA. The cells were collected for determining the mRNA expression of mEPCR by real-time PCR. RESULTS: Compared with control group, the protein level of sEPCR was significantly increased, and the mRNA expression of mEPCR was significantly decreased in 5% CSE group (both P<0.05). The protein levels of sEPCR were significantly increased, and the mRNA expression of mEPCR was significantly decreased in 100 μmol/L and 200 μmol/L simvastatin groups. However, the protein levels of sEPCR were lower, and the mRNA expression of mEPCR was significantly higher in 100 μmol/L and 200 μmol/L simvastatin groups than those in 5% CSE group. Compared with 5% CSE group, the protein levels of sEPCR in simvastatin+CSE groups were significantly decreased, but higher than those in control group and simvastatin group with corresponding concentration. On the contrary, the mRNA expression of mEPCR in simvastatin+CSE groups was significantly increased, but lower than that in control group and simvastatin group with corresponding concentration (all P<0.05). CONCLUSION: Simvastatin obviously increases the mRNA expression of mEPCR, decreases the protein level of sEPCR, and attenuates the CSE-induced endothelial injury in vitro .  相似文献   

18.
19.
AIM: To investigate the influence and mechanism of recombinant macrophage migration inhibitory factor (rMIF) on fibroblasts. METHODS: MRC-5 fibroblasts were divided into two groups: the treated group was treated with rMIF (25-100 μg/L, 12 h, 24 h or 48 h) and the control was non-rMIF treatment. The activity of proliferation in both groups was investigated and compared by CCK-8 means. Synthesis of collagen in the culture supernatants was detected by the hydroxyproline. The expression of collagen type I mRNA was examined using RT-PCR analysis. The level of collagen type I protein induced by rMIF was quantified by Western blotting. RESULTS: The production of proliferation ratio of fibroblasts treated with 50 μg/L and 100 μg/L rMIF at 24 h or 48 h were increased obviously (P<0.05 or P<0.01). The collagen synthesis significantly increased after stimulation with 100 μg/L rMIF for 48 h (P<0.01). rMIF significantly increased the expression of collagen type I mRNA and protein in a dose dependent manner compared with control (P<0.05 or P<0.01). CONCLUSION: rMIF upregulates the proliferation of fibroblasts and has an effect on the production of collagen. These results suggest that MIF may play important roles in the pathogenesis of airway remodeling.  相似文献   

20.
AIM: To investigate the effect of quercetin on endothelin-1-induced T-type calcium channel(TCC) expression in primary cultured human umbilical arterial smooth muscle cells for exploring the protective role of quercetin in cardiovascular system. METHODS: Human umbilical arterial smooth muscle cells were verified by immunocytochemistry. The cells in 2-3 passages were used and randomly divided into control group, quercetin alone group, model group and experimental group. The cells in control group were cultured without any drugs for 24 h. The cells in quercetin alone group were cultured with 80 μmol/L quercetin for 24 h. The cells in model group were cultured with ET-1 at the concentration of 100 nmol/L for 24 h. The cells in experimental groups were pretreated with quercetin for 1 h, then coincubated with 100 nmol/L ET-1 for 24 h. The concentrations of quercetin used in this study were 20, 40and 80 μmol/L, respectively. The expression of α1G, a TCC major subunit, was assayed at mRNA and protein levels by RT-PCR and Western blotting, respectively. The TCC currents(IcaT) were detected by the technique of whole-cell patch-clamp. RESULTS: Compared with control and experimental group, ICaT density (P<0.01) and the expression of α1G at mRNA (P<0.05) and protein (P<0.01) levels in model group were significantly increased. No significant difference in the results of quercetin alone group and control group was observed. CONCLUSION: The protective roles of quercetin in cardiovascular functions are related to the depressive effects of quercetin on ET-1-induced increase in both ICaT density and the expression of α1G at mRNA and protein levels in cultured human vascular smooth muscle cells.  相似文献   

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