首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
AIM To investigate the effect of β1-adrenergic receptor autoantibodies （β1-AA） on the rhythm of autophagy marker microtubule-associated protein 1 light chain 3 （LC3）, and the underlying mechanism of cardiomyocyte death. METHODS The test materials were Sprague-Dawley （SD） rats and H9c2 rat cardiomyocytes. The SD rats were randomly divided into immunization group and control group with 6 rats in each group. The H9c2 cells were randomly divided into control group, β1-AA group, lentivirus （LV）-NC group, and LV-shPer2 group （n=6）. Affinity chromatography was used for purification of β1-AA from rat serum. CCK-8 assay was used to observe the viability of cardiomyocytes treated with β1-AA for 24 h. The cells were synchronized by dexamethasone and then treated with β1-AA. The mRNA and protein levels of LC3 at different time points were determined by real-time PCR and Western blot, respectively. The Per2 protein level at different time points was also determined by by Western blot. JTK_CYCLE algorithm was used to estimate the circadian rhythm parameters. After destruction of LC3 circadian rhythm via LV-shPer2, CCK-8 assay was used to measure the viability of H9c2 cells. RESULTS High level of β1-AA in rat serum was found after active immunization compared with control group （P<0.05）. The viability of H9c2 cells in β1-AA group was significantly lower than that in control group （P<0.05）. The LC3 and Per2 rhythms were both disrupted in H9c2 cells induced by β1-AA （JTK_CYCLE P<0.05）. After LV-shPer2 infection, the LC3 rhythm was disrupted （JTK_CYCLE P<0.05） and the cell viability was reduced （P<0.05）. CONCLUSION β1-AA may induce the destruction of autophagy marker LC3 rhythm in rat cardiomyocytes and then promote cell death.  相似文献   

2.
AIMTo investigate whether adiponectin inhibits the decrease in autophagy of rat H9c2 cardiomy?ocytes induced by β1-adrenergic receptor (β1-AR) autoantibodies (β1-AA), and to explore its mechanism. METH?ODS: SD rats were actively immunized with β1-AR extracellular second loop (β1-AR-ECII) antigen peptide. Affinity chromatography was used to purify β1-AA in serum of the SD rats. The viability of H9c2 cells was measured by CCK-8 assay. The mRNA levels of LC3B and beclin-1 in the H9c2 cells were detected by real-time PCR. The protein levels of LC3-II, P62, AMP-activated protein kinase (AMPK) and phosphorylated AMPK (p-AMPK) were determined by Western blot. RESULTSPretreatment with adiponectin at 10 μg/L for 1 h reversed the decreased viability of H9c2 cells induced by β1-AA. Compared with control group, β1-AA decreased the mRNA expression of LC3B and beclin-1, decreased the protein level of LC3-II, and increased the expression of P62 protein in the H9c2 cells, suggesting that β1-AA decreased the autophagic flux in cardiomyocytes. Adiponectin obviously reversed β1-AA-induced decline in autophagic flux, and up-regulated the phosphorylation level of AMPK decreased by β1-AA. Treatment with AMPK inhibitor Compound C for 30 min, we observed that the mRNA expression of LC3B and beclin-1 and the protein level of LC3-II in the H9c2 cells decreased by β1-AA were not effectively reversed by adiponectin, but the increase in P62 protein expression was still effectively reversed, indicating that adiponectin increased autophagosome production dependent on the AMPK pathway, but increased autophagosome clearance independent on the AMPK pathway. CONCLUSION Adiponectin inhibits the decreased autophagy of H9c2 cardiomyocytes induced by β1-AA.  相似文献   

3.
AIM: To examine the autoantibody against α1-adrenoceptor and its biologic activities during the development of renal hypertension. METHODS: Renal hypertension of rat was achieved by clipped renal artery, the titre of autoantibody to α1-adrenoceptor was detected using ELISA immunoassay. Furthermore, the biological offects of these autoantibodies on cultured cardiomyocytes were also examined. RESULTS: After two weeks of clipping renal arteries, both the frequency of occurrence and the titre of autoantibodies to cardiac α1-adrenergic receptor were significantly increased as compared with the control of pre-treatment. The increased autoantibodies lasted for several weeks and then automatically decreased gradually to the pre-clipping level at 12 weeks. The biological effects of these autoantibodies displayed an "agonistic-like" activities on the beating frequency of cultured neonatal cardiomyocytes. CONCLUSION: Autoantibodies against α1-adrenoceptor may play a role in the elevation of peripheral vascular resistance and in the development of cardiac hypertrophy in rats with renal hypertension.  相似文献   

4.
AIM: To observe the effect of B-HT933, a selective α2-adrenoceptor agonist, on lipopolysaccharide(LPS)-induced TNF-α production in neonatal rat cardiomyocytes and to explore the underlying mechanisms.METHODS: The neonatal rat cardiomyocytes were cultured. The localization of α2A-adrenoceptor in the cardiomyocytes was examined by immunofluorescence staining. The cardiomyocytes were exposed to LPS or/and B-HT933 for different time. The level of TNF-α in the supernatants and the mRNA expression of TNF-α were detected by ELISA and real-time PCR, respectively. In addition, LPS-associated signal molecules in the cardiomyocytes were also examined by Western blotting.RESULTS: Immunofluorescence staining showed that α2A-adrenoceptors were localized in the cardiomyocytes. LPS stimulated TNF-α production in the cardiomyocytes in a dose and time-dependent manner. B-HT933 pretreatment significantly inhibited the expression of TNF-α at mRNA and protein levels in LPS-treated cardiomyocytes. Furthermore, LPS exposure induced IκBα and p38 phosphorylation in cardiomyocytes and only IκBα phosphorylation was prevented by B-HT933 treatment.CONCLUSION: α2A-adrenoceptors are present in neonatal rat cardiomyocytes and its agonist B-HT933 inhibits LPS-induced TNF-α production in cardiomyocytes via suppressing IκBα phosphorylation.  相似文献   

5.
AIM: To investigate the effects of curcumin (Cur) on the expression of High mobility group box 1 protein (HMGB1), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) in amyloid-β (Aβ)-induced primary rat microglial cells. METHODS: Microglia were derived from the cerebral cortices of postnatal rat brains. The cells were identified by immunocytochemistry using mouse anti rat Iba-1 monoclonal antibody. A cell model using primary rat microglial cells incubated with Aβ25-35 as an inflammation model of Alzheimer's disease (AD) was set up. The morphological characters of primary rat microglial cells were observed. The concentration of Aβ25-35 and the treatment concentration of curcumin were selected by CCK-8 assay. Cultured primary rat microglial cells were divided into 5 groups:normal cell group, Aβ25-35 group, Cur group, Aβ25-35+Cur group and Aβ25-35+DMSO group. The expression of HMGB1, NF-κB, and receptor for advanced glycation end products (RAGE) was detected by Western blot. The levels of HMGB1, IL-1β, and TNF-α in the culture supernatant were measured by ELISA. RESULTS: The purity of primary microglias determined by Iba-1 immunofluorescence was more than 95%. The protein levels of HMGB1, RAGE and NF-κB were significantly increased after Aβ25-35 stimulation. After treatment with Cur, the protein levels of HMGB1, RAGE and NF-κB were significantly decreased (P<0.05). The levels of HMGB1, IL-1β and TNF-α in the supernatant were significantly increased after Aβ25-35 stimulation. Cur significantly decreased the level of HMGB1, IL-1β and TNF-α in the supernatant. CONCLUSION: Curcumin significantly inhibits neuroinflammation stimulated by Aβ25-35 in primary rat microglial cells.  相似文献   

6.
AIM:To explore the protective effect of morinda officinalis oligosaccharides monomer HexB on hypoxia/reoxygenation (H/R)-induced injury in human umbilical vein endothelia cells (HUVECs). METHODS:HUVECs were treated with HexB, 4-phenylbutyric acid (4-PBA) and thapsigargin (TG), respectively. The cells were divided into control group, HexB group, H/R group, HexB+H/R group, 4-PBA+H/R group, TG group and HexB+TG group. The cell viability was measured by CCK-8 assay. The apoptotic rate was detected by flow cytometry. Western blot was used to determine the protein levels of endoplasmic reticulum stress (ERS) related molecules chaperone protein glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP), apoptosis-related protein caspase-12 and phosphorylated c-Jun NH2-terminal kinase (p-JNK). RESULTS:The viability of HUVECs was reduced in H/R group and TG group (P<0.05), increased in HexB+H/R, 4-PBA+H/R and HexB+TG group (P<0.05). The apoptotic rate, the protein levels of GRP78, CHOP, caspase-12 and p-JNK were increased in H/R group and TG group (P<0.05), weakened in the HexB+H/R group (P<0.05), 4-PBA+H/R group and HexB+TG group (P<0.05). No significant change in the apoptotic rate, cell viability, protein levels of GRP78, CHOP, caspase-12, p-JNK between HexB+H/R group and 4-PBA+H/R group was observed. CONCLUSION:HexB attenuates HUVECs injury caused by H/R through suppressing ERS and apoptosis. The possible mechanism may be involved in the apoptotic pathways related to GRP78, CHOP, caspase-12 and p-JNK.  相似文献   

7.
AIM: To observe the expression of Akt/GSK-3β/Snail signaling pathway-related molecules in cisplatin-resistant cell line A549/DDP mediated by transforming growth factor-β1 (TGF-β1), and to explore the association of Akt/GSK-3β/Snail signaling pathway with epithelial-mesenchymal transition (EMT). METHODS: The A549/DDP cells were divided into TGF-β1 (+) group, TGF-β1 (-) group and LY294002 group. The morphological changes of A549/DDP cells treated with TGF-β1 were observed under microscope. The protein expression of E-cadherin and N-cadherin was determined by the methods of immumofluorescence and Western blot. The protein levels of Akt, p-Akt, GSK-3β, p-GSK-3βSer9 and Snail were also detected by Western blot. RESULTS: The A549/DDP cells in TGF-β1 (+) group were dispersive, showed a spindle-like shape and developed pseudopodia. This transformation was conformed to classic EMT markers. Compared with TGF-β1 (-) group, the protein expression of E-cadherin in TGF-β1 (+) group was significantly decreased (P<0.05), and N-cadherin was significantly increased (P<0.05). The protein levels of p-Akt, p-GSK-3βSer9 and Snail were also significantly increased (P<0.05). Compared with TGF-β1 (+) group, the protein levels of p-Akt, p-GSK-3βSer9 and Snail were significantly decreased in LY294002 group (P<0.05). No difference of Akt and GSK-3β expression between TGF-β1 (-) group and TGF-β1 (+) group was observed. CONCLUSION: The mechanism of EMT in A549/DDP cells might be related to Akt/GSK-3β/Snail signaling pathway activated by TGF-β1.  相似文献   

8.
SHAO Qi  CAO Fei  LI Mei  ZHANG Yan 《园艺学报》2016,32(12):2233-2238
AIM: To study the effect of integrin β1 on multidrug resistance in gastric cancer and its possible mechanisms. METHODS: The expression of integrin β1 at mRNA and protein levels in the SGC-7901 cells and SGC-7901/DDP cells was determined by qPCR and Western blot. The expression of integrin β1 in the SGC-7901/DDP cells was silenced by antisense oligodeoxynucleotide. The cell viability was detected by the CCK-8 assay, the cell apoptosis were analyzed by flow cytometry, and the protein levels of integrin β1, Bcl-2/Bax, cleaved caspase-3/caspase-3, cytochrome C (Cyt-C) and p-AKT/AKT were determined by Western blot.RESULTS: The expression of integrin β1 at both mRNA and protein levels was significantly upregulated in SGC-7901/DDP cells. The expression of integrin β1 was increased in SGC-7901 cells treated with chemotherapeutic agents such as cisplatin, paclitaxel and 5-fluorouracil. Knockdown of integrin β1 induced apoptosis of SGC-7901/DDP cells with an increased sensitivity to the chemotherapeutic agents. Meanwhile, knockdown of integrin β1 downregulated the protein levels of Bcl-2/Bax, p-AKTSer473 and p-AKTThr308, while promoted the release of Cyt-C and upregulated the protein level of cleaved caspase-3. CONCLUSION: Knockdown of integrin β1 increases the sensitivity of SGC-7901/DDP cells to the chemotherapeutic agents, and promotes the cell apoptosis via mitochondrial apoptosis pathway. The mechanism may be related to the attenuation of AKT pathway by inhibiting phosphorylations of AKT at Ser473 and Thr308.  相似文献   

9.
AIM: To study the correlation between phasic change of the relative quantity of major crystallins with aging in rats. METHODS: Six groups of SD rats (age 1 d， 8 d，2 weeks，8 weeks，8 months and 1.5 years) were raised routinely. Water soluble crystallins were extracted and separated by two－dimensional polyacrylamide gelelectrophoresis. After comassize blue staining，the crystallins patterns were scanned and analyzed. RESULTS: (1) Out of the eighteen water soluble major rat crystallins tested in each group, seven showed gradual phasic changes in relative quantity of crystallins, but there were no significant changes in total quantity of water soluble crystallins. (2) Phasic changes in these crystallins presented four different patterns: increasing (βB4、αB2、αA2、βA1), decreasing (β7、β8、γ2,3、γ5,6),relatively stable(βA3、βB5), and irregular. (3) The ratio of βB4 /αA2 increased gradually with the rat aging process. CONCLUSION: The gradual phasic changes in relative quantity of crystallins reflect the aging status of rat crystalline.  相似文献   

10.
AIM:To investigate the role of endoplasmic reticulum(ER) stress in the process of hypoxia-induced neonatal rat myocardial injury through PERK signal pathway. METHODS:Neonatal rat cardiac myocytes were randomly divided into control group and hypoxia 1 h, 4 h, 8 h, 12 h and 24 h groups. Cell viability was evaluated by determining the intracellular content of ATP. Apoptosis was measured by high-content analysis(HCA) cell imaging system. The protein levels of GRP78, calreticulin, p-PERK, p-eIF2α, ATF4 and CHOP were detected by Western blotting at different time points. The primary cultured neonatal rat cardiac myocytes were treated with an agonist of PERK pathway salubrinal and the cell apoptosis was observed under hypoxia. RESULTS:In the early phase, hypoxia induced an increase in the expression of calreticulin and GPR78. In the middle phase of hypoxia, the levels of p-PERK, p-eIF2α and ATF4 were increased. In the later phase of hypoxia, increased CHOP level was also observed. Salubrinal effectively protected the cardiac myocytes from hypoxic injury. CONCLUSION:Hypoxia activates ER stress in cardiac myocytes and also activates PERK signal pathway. PERK signaling protects cardiac myocytes from hypoxic damage in the early stage and triggers apoptosis of the cells in the later phase.  相似文献   

11.
AIM: To investigate the effect of platelet-derived growth factor (PDGF) on β3 integrin gene expression and the role of β3 integrin on adhesion, migration and proliferation of vascular smooth muscle cells (VSMC) induced by PDGF. METHODS: β3 integxin gene expression was detected by RT-PCr. After β3 integrin extracellular do-main was blocks, VSMC adhesio, migration and proliferation were measured by adhesion assay awound-culture model an [3H]-TSR incorporation respectively.RESULTS: After the interaction between β3 integrin and extracellular matrix was blocked, VSMC proliferation was inhibited in some degree and the rate of [3H]-TdR incorporation into VSMC decreased 39%. The cell adhesion and migration were significantly inhibited when 10 mg/L anti-β3 integrin antibody was added (P＜0.05). When VSMC were treated by PDGF for 6 hours, the expression of β3 integrin gene was 87% higher than that of control. CONCLUSION: PDGF significantly induces expression of β3 integrin gene in VSMC, and the interaction between β3 integrin and ECM protein may play an important role in VSMC adhesion and migration.  相似文献   

12.
AIM: To observe the expression of transforming growth factor β1 (TGF-β1), MAPK1/3 and fibronectin (FN) in the development of renal tubulointerstitial disease. METHODS: Wistar male rats were randomly divided into normal control group, diabetic group of 1week, 2 weeks, 4 weeks and 8 weeks. Diabetic model was induced by peritoneal injection of streptozotocin. Immunohistochemistry was employed to detect the expression of TGF-β1, MAPK1/3 and FN in the kidney. TGF-β1 protein in the renal cortex was checked by Western blot. BG, Scr and UP were analysed by biochemical methods, and the morphological changes in renal tubulointerstitium were also examined under microscopy on sections stained with HE and PAS. RESULTS: The expression of MAPK1/3 and FN was observed, but not the expression of TGF-β1 in normal renal tissue. Positive staining of TGF-β1 was observed in the renal tubulo-interstitium in 1-week diabetic group and thereafter it increased in the course of diabetes. A continuous increase in the expression of MAPK1/3 and FN was also observed in two - week diabetic rats. Chronologically the expression of TGF-β1,MAPK1/3 and FN and the ratio of KW/BW were positively correlative with each other in diabetic animals except one -week diabetic rats. There was also a positive correlation between MAPK1/3 and FN in l -week diabetic rats. CONCLUSION: Our data suggest that TGF-β1 appears in the renal tubulointerstitium in early period of diabetes and then its signal is mediated by MAPK1/3 cascades to accelerate production of FN ,and in turn leads to renal hypertrophy and tubulointerstitial fibrosis.  相似文献   

13.
AIM: To investigate whether transforming growth factor-β1 (TGF-β1) participates in hypoxia-induced bronchial epithelial-mesenchymal transition (EMT) through lysyl oxidase (LOX). METHODS: Sprague-Dawley (SD) rats were exposed to hypoxia to establish the animal model and were treated with LOX inhibitor β-aminopropionitrile (β-APN). Furthermore, primary rat bronchial epithelial cells were cultured in vitro and exposed either to normoxia or to hypoxia. TGF-β1, TGF-β1 receptor inhibitor (SB431542) or β-APN was used in the cell experiments. The content of collagen was measured by colorimetric method. The expression of TGF-β1, LOX, and 2 EMT-related proteins (namely, the epithelial marker E-cadherin and the mesenchymal marker vimentin) were determined by immunohistochemistry and We-stern blot, respectively. RESULTS: The expression of TGF-β1, vimentin and LOX and cross-linking of collagen were enhanced in hypoxia-exposed rat and in hypoxia-exposed bronchial epithelial cells, but the enhancement was impaired by the treatment with β-APN. In contrast, the expression of E-cadherin was reduced in hypoxia-exposed rat, and was reversed by treatment with β-APN. In vitro experiments demonstrated that TGF-β1 and hypoxia led to the morphological phenotype characteristic of EMT in rat bronchial epithelial cells, in which the morphology of rat bronchial epithelial cells was switched from cobble-stone shape in normoxia-exposed group to spindle fibroblast-like morphology in hypoxia-or TGF-β1-exposed group (P<0.01). Additionally, both β-APN and SB431542 partially prevented TGF-β1 and hypoxia induced EMT in rat bronchial epithelial cells. TGF-β1was able to dose-dependently up-regulate LOX expression in rat bronchial epithelial cells, which was blocked by concurrent incubation with SB431542. The up-regulation of TGF-β1, vimentin, LOX and cross-linking of collagen and down-regulation of E-cadherin in hypoxia-exposed rat bronchial epithelial cells was significantly reversed by incubation with SB431542. CONCLUSION: TGF-β1 regulates hypoxia-induced EMT in bronchial epithelial cells via activation of the LOX.  相似文献   

14.
AIM:To explore the effects of different β-adrenergic receptors (β-AR) on the left and right ventricular systolic and diastolic functions in rats under acute hypoxic stress. METHODS:The healthy male SD rats were randomly divided into 4 groups (n=7):control group, non-selected β-AR blocker propranolol group, selected β1-AR blocker atenolol group and selected β2-AR blocker ICI 118,551 group, and then the rats were exposed to normoxia (20.9% O2, 79.1% N2) and hypoxia (15.0% O2, 85.0% N2) condition respectively at the altitude of 2 260 m (Xining, China). The heart rate (HR), the left ventricular systolic pressure (LVSP), the right ventricular systolic pressure (RVSP), and the maximum raise/decline rate of left and right ventricular pressure (±dp/dtmax) were monitored, and the arterial blood gas in normoxia and hypoxia condition were compared to explore the effect of β-AR on the left and right ventricular systolic and diastolic functions in acute hypoxic stress rats. RESULTS:Under normoxia condition, the LVSP, ±dp/dtmax of left ventricular were decreased in propranolol group, atenolol group and ICI 118,551 group, the RVSP and ±dp/dtmax of right ventricle were decreased in propranolol group and atenolol group (P<0.05). Under hypoxia condition, the PaO2, LVSP, ±dp/dtmax of left ventricle were decreased in all groups compared with the normoxia group, and the ±dp/dtmax of right ventricle was increased in all groups (P<0.05), also the degree of index change in control group was more obvious than that in propranolol group and atenolol group. CONCLUSION:The activation of β1-AR is an important compensatory regulation for heart function during hypoxic stress. However, the compensatory enhancement of right heart function under acute hypoxia condition which through tonogenic dilation is more significant for maintaining the normal circulating blood flow.  相似文献   

15.
AIM:To investigate the effect of tenuigenin(TEN) on hyperphosphorylation of tau protein in neurons of amyloid β-peptide1-40(Aβ1-40) -induced Alzheimer disease(AD) rats. METHODS:Aβ1-40 was injected into hippocampus CA1 region of the rats to establish AD model. TEN at different doses(18.5 mg/kg, 37.0 mg/kg and 74.0 mg/kg) was intragastrically administered. The protein expression of protein kinase A(PKA),protein phosphatase 2A(PP2A), total tau and p-tau(Ser396) in the neurons was observed by the method of immunohistochemistry. The protein content of total tau and p-tau(Ser396), and the expression level of PKA and PP-2A were detected by Western blotting analysis. RESULTS:In Aβ1-40 group, the level of total tau, the phosphorylation of tau protein and the expression of PKA were significantly increased compared with those in sham operation group. Meanwhile, the expression of PP2A in Aβ1-40 group was lower than that in sham operation group. In TEN treatment group, the level of total tau, the phosphorylation of tau protein and the expression of PKA were markedly decreased, and the expression of PP2A was increased as compared with Aβ1-40 group. CONCLUSION:TEN may protect the neurons from the toxic effect of Aβ1-40 and reduce the hyperphosphorylation of tau(Ser396) in the neurons of AD rats by activating the expression of PP2A and inhibiting the expression of PKA.  相似文献   

16.
AIM: To investigate the effect of enhancer of zeste homolog 2 (EZH2) regulating Wnt/β-catenin signaling pathway on the apoptosis of brain glioma cell lines. METHODS: The expression level of EZH2 in glioma cell lines U87, H4 and U251 and normal human astrocytes (NHA) was detected by RT-qPCR and Western blot. The EZH2 siRNA and siRNA control were transfected into the H4 cells. The cell viability was measured by MTT assay. The apoptosis was analyzed by flow cytometry. Caspase-3 activity was detected by spectrophotometry. The expression levels of the key protein β-catenin of the Wnt/β-catenin signaling pathway and the downstream target molecule c-Myc were determined by Western blot. After the H4 cells transfected with EZH2 siRNA were treated with an activator of Wnt/β-catenin signaling pathway, the apoptosis rate was measured by flow cytometry, and the expression of β-catenin and c-Myc was determined by Western blot. RESULTS: The mRNA and protein expression levels of EZH2 in the glioma cell lines U87, H4 and U251 were significantly higher than those in NHA (P<0.05). The expression of EZH2 at mRNA and protein levels in the H4 cells was higher than that in U87 cells and U251 cells (P<0.05). EZH2 siRNA obviously inhibited the expression of EZH2 at mRNA and protein levels in the H4 cells. Knockdown of EZH2 expression decreased the viability of H4 cells, the apoptotic rate was significantly increased, and the activity of caspase-3 was significantly increased in the cells (P<0.05). Knockdown of EZH2 expression also inhibited the expression of β-catenin and c-Myc. The activator of Wnt/β-catenin signaling pathway reduced the apoptosis rate of H4 cells induced by down-regulation of EZH2, and reduced the activity of caspase-3 in the cells. CONCLUSION: EZH2 is over-expressed in glioma cells. Down-regulation of EZH2 expression induces apoptosis of glioma cells by inhibiting the activation of Wnt/β-catenin signaling pathway.  相似文献   

17.
XU Qi  DONG Er-dan  CHEN Kai  HAN Qi-de 《园艺学报》2002,18(12):1544-1547
β3-adrenergic receptor is the third subtype of β-adrenergic receptors. The genetic structure and pharmacological property of β3-adrenergic receptor are markedly distinguished from β1-and β2-adrenergic receptor subtypes. Recently studies show that myocardial β3-adrenergic receptor mediates negative inotropic effect through Gi-protein/NO/cGMP pathway, the expression of β3-adrenergic receptor and negative inotropic effect mediated by β3-adrenergic receptor are increased in heart failure. However, because of the low expression of β3-adrenergic receptor in the heart, the actual pathophysiological significance of β3-adrenergic receptor remains unknown.  相似文献   

18.
AIM: To investigate the role of α1 and β2 adrenoceptors(α1AR and β2AR) in the proliferation of hypoxic pulmonary artery smooth muscle cells (PASMCs).METHODS: PASMCs were isolated by an explant method from neonatal bovine pulmonary arteries. The cultured PASMCs were exposed to 6.6% O2 for 6 h, 12 h and 24 h. The method of -TdR incorporation was used to measure the proliferation of PASMCs. i was assayed with Fura-2/AM. The mRNA expression of α1AR, β2AR, c-fos and c-myc was determined by Northern blotting. The effects of activation of α1AR and β2AR, and inhibition of α1AR on the above indexes were observed by treating PASMCs with different AR agonists and antagonists under hypoxic condition.RESULTS: Significant increase in TdR incorporation in hypoxic PASMCs with α1AR activation was observed, and marked decrease in that was induced by α1AR inhibition. However, no significant change was found after β2AR activation. i , the mRNA expression of c-fos, c-myc, α1AR and β2AR in PASMCs were increased after hypoxia.CONCLUSION: Hypoxia induces the increase in i and mRNA expression of c-fos and c-myc, leading to the proliferation of PASMCs. The hypoxic proliferation of PASMCs is intervened by α1AR, but not β2AR. The remodeling of pulmonary arteriole and pulmonary hypertension may be involved in the processes of pulmonary arteriole constriction and proliferation induced by hypoxia through up-regulation of α1AR.  相似文献   

19.
LIU Xiu-ping  L&#  Ling-yun  LI Xia-chun 《园艺学报》2018,34(12):2215-2220
AIM:To investigate the inhibitory effect of 4-phenylbutyric acid (4-PBA), an aromatic short-chain fatty acid with the functions of endoplasmic reticulum (ER) molecule chaperon, on ER stress-induced decreases in both dendritic spine density and synaptic protein expression. METHODS:Primary hippocampal neurons were cultured from neonatal rats. The primary hippocampal neurons were transfected with enhanced green fluorescent protein plasmids at DIV (day in vitro) 5~7. At DIV 20, the neurons were divided into DMSO group, tunicamycin group and tunicamycin+4-PBA (treated with 4-PBA 1 h before tunicamycin) group. The expression levels of ER stress marker protein BiP and synaptic proteins were detected by Western blot. After immunofluorescence staining, the neurons were morphologically observed under confocal laser scanning microscope, and the density of dendritic spines was analyzed. At last, the cell viability was measured by MTT assay. RESULTS:Tunicamycin induced ER stress in the primary hippocampal neurons, characterized by significantly increased level of BiP in tunicamycin group, which was reduced in tunicamycin+4-PBA group (P<0.05). 4-PBA inhibited tunicamycin-induced decreases in both dendritic spine density and synaptic protein expression in the primary hippocampal neurons. 4-PBA attenuated tunicamycin-induced decrease in the cell viability. CONCLUSION:4-PBA not only attenuates ER stress of primary hippocampal neurons but also inhibits the decreases in both dendritic spine density and synaptic protein expression induced by tunicamycin.  相似文献   

20.
YANG Yi  TANG Xiao-li  LIU Yue  FANG Fang 《园艺学报》2019,35(11):2028-2034
AIM: To explore whether the damage of neurons induced by amyloid β-protein (Aβ) is related to the regulation of autophagy and its mechanism based on Akt/mTOR pathway. METHODS: SH-SY5Y cells were incubated with Aβ25-35 (5 μmol/L, 10 μmol/L, 15 μmol/L, 20 μmol/L and 25 μmol/L) for 24 h, and the cell viability was measured by MTT assay. The protein levels of LC3-I, LC3-II, Akt, p-Akt, mTOR and p-mTOR in the SH-SY5Y cells were determined by Western blot. After the SH-5Y5Y cells were incubated with autophagy inducer rapamycin (Rapa) or autophagy inhibitor 3-methyladenine (3-MA) combined with Aβ25-35 for 24 h, the cell viability and related protein expression were detected by the same methods above mentioned. RESULTS: Each concentration of Aβ25-35 damaged SH-SY5Y cells and decreased the viability of SH-SY5Y cells. Aβ25-35 increased the expression of autophagy marker protein LC3-II, increased the level of LC3-II/LC3-I, and down-regulated the phosphorylation level of Akt and mTOR proteins (P<0.05). When combined with autophagy inducer Rapa, the cell viability was not significantly affected, the expression of LC3-II protein was increased, LC3-II/LC3-I was increased significantly, and p-mTOR/mTOR level was decreased (P<0.05). When combined with autophagy inhibitor 3-MA, the protein expression of LC3-II and the level of LC3-II/LC3-I showed a downward trend, while the level of p-Akt/Akt was decreased (P<0.05). CONCLUSION: Aβ25-35 may induce SH-SY5Y cell autophagy and injury by down-regulating phosphorylation levels of Akt and mTOR proteins.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号