共查询到20条相似文献，搜索用时 46 毫秒
1.
试验旨在研究胰岛素样生长因子-1（insulin-like growth factor 1,IGF-1）对奶牛乳腺上皮细胞（bovine mammary epithelial cells,BMECs）增殖的影响,为后期利用IGF-1调控乳腺发育奠定理论基础。以奶牛乳腺上皮细胞为材料,首先分4组分别外源添加0（对照组）、10、50、100 μg/mL IGF-1且分别培养12、24、48、72 h,测定抑制BMECs凋亡率的最佳浓度;然后分6组：单纯BMECs组、BMECs+IGF-1组、BMECs+LY294002组、BMECs+IGF-1+LY294002组、BMECs+RAPA组和BMECs+IGF-1+RAPA组,采用流式细胞术测定各组细胞凋亡率。结果表明,外源性添加IGF-1对BMECs凋亡率具有抑制作用,最佳浓度为50 μg/mL;BMECs+IGF-1+LY294002与BMECs+IGF-1+RAPA组细胞凋亡率均极显著高于BMECs+IGF-1组（P<0.01）。推断IGF-1能够活化PI3K/Akt/mTOR信号通路,参与BMECs凋亡的调控作用,进而抑制BMECs细胞凋亡;IGF-1可能会对被抑制PI3K/Akt/mTOR信号通路产生"修复"机制,使其能够重新参与BMECs的生命进程。 相似文献
2.
Insulin-like growth factor-I is involved in mammary gland development, promoting proliferation and inhibiting apoptosis of mammary epithelial cells (MECs). Mitogenic actions of IGF-I are mainly mediated by the phosphatidylinositol-3 kinase (PI3K)/Akt signaling pathway. We have found that in the presence of IGF-I bovine BME-UV1 MECs cultured on reconstituted basement membrane form large spheroids with disrupted polarity and no cavity in the center. These cells showed enhanced phosphorylation of Akt, decreased level of cleaved caspase-3, and sustained proliferative activity throughout the 16-d period of 3-dimensional culture. Inhibition of the PI3K/Akt pathway by a specific inhibitor of PI3K, LY294002, resulted in the restoration of the normal acinar phenotype. However, this effect was noted only when LY294002 was added in the second week of 3-dimensional culture, which corresponded with the time of cell cycle arrest and polarity formation under control conditions. Normal development of acini was also obtained when BME-UV1 cells were treated simultaneously with IGF-I and 17β-estradiol. The addition of 17β-estradiol regulated Akt activation, enabling the subsequent initiation of polarization processes. 17β-Estradiol also increased the level of IGFBP-3 protein in MECs cultured on Matrigel in the presence of IGF-I. The presented results indicate important interactions between signaling pathways activated by estrogen and IGF-I, which regulate alveologenesis in bovine mammary gland. 相似文献
3.
试验旨在研究雌激素对奶牛乳腺上皮细胞（BMECs）凋亡及生长周期的影响。通过添加MAPK/ERK信号通路阻断剂探索雌激素调控BMECs凋亡及生长周期具体的作用机制,采用流式细胞仪检测细胞凋亡及周期的变化情况,实时荧光定量PCR检测Bcl-2、Caspase3及CyclinD1基因mRNA的表达丰度。结果显示,对照组BMECs凋亡率极显著低于BMECs+PD98059、BMECs+E2+PD98059组（P<0.01）,Bcl-2 mRNA表达丰度极显著高于BMECs+PD98059组（P<0.01）,Caspase3 mRNA表达丰度显著低于BMECs+PD98059组（P<0.05）;对照组细胞比例在G1期显著高于BMECs+E2组（P<0.05）,极显著低于BMECs+E2+PD98059组（P<0.01）,S期细胞比例极显著高于BMECs+PD98059、BMECs+E2+PD98059组（P<0.01）,G2期细胞比例极显著低于BMECs+PD98059、BMECs+E2+PD98059组（P<0.01）;对照组CyclinD1 mRNA的表达丰度极显著高于BMECs+PD98059组（P<0.01）;BMECs+E2+PD98059组的Bcl-2 mRNA的表达量极显著高于BMECs+PD98059组（P<0.01）,Caspase3 mRNA的表达量显著低于BMECs+PD98059组（P<0.05）。结果表明,MAPK/ERK信号通路参与BMECs的增殖及细胞生长周期调节的过程,且雌激素可通过MAPK/ERK信号通路抑制BMECs的凋亡,MAPK/ERK信号通路可能参与由雌激素调控的细胞生长周期的进程。 相似文献
4.
Inhibition of PI3K‐Akt‐mTOR signal pathway dismissed the stimulation of glucose on goose liver cell growth 
下载免费PDF全文
下载免费PDF全文 S. Wei C. Han F. He Q. Song B. Kang H. Liu L. Li H. Xu X. Zeng 《Journal of animal physiology and animal nutrition》2017,101(5):e133-e143
In the formation of goose fatty liver induced by a high‐carbohydrate diet, it is characterized by the quick cell growth of liver. The carbohydrate is mostly digested and absorbed in the small intestine by the form of glucose. Recent studies have suggested a crucial role for PI3K‐Akt‐mTOR pathway in regulating cell proliferation, and then we speculate that PI3K‐Akt‐mTOR pathway may mediate glucose‐induced liver cell proliferation. Goose primary hepatocytes were isolated and incubated in either no addition as a control or glucose or PI3K‐Akt‐mTOR pathway inhibitors or cotreatment with glucose and PI3K‐Akt‐mTOR pathway inhibitors. The results firstly showed that 35 mmol/l glucose stimulated the mRNA level and protein content of factors involved in PI3K‐Akt‐mTOR signal pathway in goose primary hepatocytes. Secondly, 35 mmol/l glucose evidently changed the cell cycle PI index and protein expression of cyclin D1. Meanwhile, the upregulation of 35 mmol/l glucose on the DNA synthesis rate, cell cycle PI index, the mRNA expression, protein content and protein expression of factors involved in the cell proliferation was decreased significantly by the inhibitors of PI3K‐Akt‐mTOR pathway, LY294002, rapamycin or NVP‐BEZ235. In summary, glucose could stimulate the cell proliferation, and the PI3K‐Akt‐mTOR pathway inhibitors could dismiss glucose‐induced the upregulation of cell proliferation in goose primary hepatocyte. 相似文献
5.
Background
Phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway, activated during influenza A virus infection, can promote viral replication via multiple mechanisms. Direct binding of NS1 protein to p85β subunit of PI3K is required for activation of PI3K/Akt signaling. Binding and subsequent activation of PI3K is believed to be a conserved character of influenza A virus NS1 protein. Sequence variation of NS1 proteins in different influenza A viruses led us to investigate possible deviation from the conservativeness.Results
In the present study, NS1 proteins from four different influenza A virus subtypes/strains were tested for their ability to bind p85β subunit of PI3K and to activate PI3K/Akt. All NS1 proteins efficiently bound to p85β and activated PI3K/Akt, with the exception of NS1 protein from an H5N1 virus (A/Chicken/Guangdong/1/05, abbreviated as GD05), which bound to p85β but failed to activate PI3K/Akt, implying that as-yet-unidentified domain(s) in NS1 may alternatively mediate the activation of PI3K. Moreover, PI3K inhibitor, LY294002, did not suppress but significantly increased the replication of GD05 virus.Conclusions
Our study indicates that activation of PI3K/Akt by NS1 protein is not highly conserved among influenza A viruses and inhibition of the PI3K/Akt pathway as an anti-influenza strategy may not work for all influenza A viruses. 相似文献6.
7.
试验旨在探讨无血清条件下脐带间充质干细胞（UC-MSCs）和奶牛乳腺上皮细胞（BMECs）共培养对类胰岛素样生长因子-Ⅰ（IGF-Ⅰ）表达的影响,将UC-MSCs和BMECs按1：2直接共培养,对比单纯培养的两种细胞,48 h时利用ELISA法检测各组上清IGF-Ⅰ浓度水平,再利用Transwell小室将两种细胞分离培养,实时荧光定量 PCR检测各组细胞IGF-ⅠR、IGF-Ⅰ mRNA的表达。结果显示,共培养中IGF-Ⅰ浓度显著高于UC-MSCs组（P < 0.05）,极显著高于BMECs组（P < 0.01）;UC-MSCs/BMECs、BMECs/UC-MSCs组IGF-Ⅰ mRNA表达值均极显著高于单纯培养组（P < 0.01）,BMECs/UC-MSCs组显著高于UC-MSCs/BMECs组（P < 0.05）;UC-MSCs/BMECs、BMECs/UC-MSCs组IGF-ⅠR mRNA表达值显著或极显著高于单纯培养组（P < 0.05;P < 0.01）,BMECs/UC-MSCs组较UC-MSCs/BMECs组差异显著（P < 0.05）。综上,体外无血清培养条件下,UC-MSCs和BMECs共培养可显著提高IGF-ⅠR及IGF-Ⅰ mRNA表达,IGF-Ⅰ浓度水平和IGF-ⅠR mRNA的表达具有一致性,IGF-Ⅰ主要存在于UC-MSCs中。 相似文献
8.
The study was aimed to explore the effect of umbilical cord mesenchymal stem cells(UC-MSCs) and bovine mammary gland epithelial cells (BMECs) under the serum-free co-culturing condition on expression of IGF-Ⅰ. UC-MSCs and BMECs were co-cultured directly at the concentration ratios of 1:2,in control groups, UC-MSCs and BMECs were cultured alone.Using ELISA method to detect the IGF-Ⅰlevels in each group supernatant at 48 h, and two kinds of cells were separated by Transwell Chambers, the IGF-Ⅰ and IGF-ⅠR mRNA expression values of each group were estimated with Real-time PCR. The results showed that the IGF-Ⅰ concentration of UC-MSCs and BMECs mixed co-culture was significantly higher than the UC-MSCs group (P < 0.05),and extremely significantly higher than the BMECs group (P < 0.01); The IGF-Ⅰ mRNA expression of UC-MSCs/BMECs and BMECs/UC-MSCs groups were extremely significantly higher than the control group (P < 0.01),and the IGF-Ⅰ mRNA expression of BMECs/UC-MSCs group was significantly higher than the UC-MSCs/BMECs group (P < 0.05); The IGF-ⅠR mRNA expression of UC-MSCs/BMECs and BMECs/UC-MSCs groups were higher than the control group (P < 0.05;P < 0.01), BMECs/UC-MSCs group had significant difference compared with UC-MSCs/BMECs group (P < 0.05). Conclusively, the co-culture of UC-MSCs and BMECs was able to improve the IGF-ⅠR and IGF-Ⅰ mRNA expression under the serum-free condition in vitro,and the IGF-Ⅰ concentration level was correspondence with the IGF-ⅠR mRNA expression, IGF-Ⅰmainly existed in UC-MSCs. 相似文献
9.
本试验旨在探究Janus激酶/信号转导及转录活化因子(JAK/STAT)信号通路是否参与脐带间充质干细胞(UC-MSCs)通过类胰岛素样生长因子-Ⅰ(IGF-Ⅰ)抑制奶牛乳腺上皮细胞(BMECs)凋亡的调节。将UC-MSCs和BMECs利用TranswellTM小室双层共培养,以BMECs单纯培养为对照,给予类胰岛素样生长因子-Ⅰ受体(IGF-ⅠR)抑制剂AG1024进行干预,并用信号阻断剂AG490处理细胞,24 h后采用实时荧光定量PCR检测各组细胞B细胞淋巴瘤/白血病-2(Bcl-2)、B细胞淋巴瘤/白血病基因伴随蛋白x(Bax)、半胱氨酸蛋白酶3(Caspase-3)基因的相对表达丰度,流式细胞仪检测细胞凋亡情况。结果表明:UC-MSCs和BMECs共培养组BMECs的凋亡率极显著低于其他各组(P0.01);UC-MSCs和BMECs共培养组Bcl-2基因的相对表达丰度较BMECs组极显著上调(P0.01),Caspase-3、Bax基因的相对表达丰度则显著或极显著下调(P0.05或P0.01);AG1024和AG490单独处理或二者共同处理升高了单独培养的BMECs和与UC-MSCs共培养的BMECs的凋亡率,并上调了Bax、Caspase-3基因的相对表达丰度,下调了Bcl-2基因的相对表达丰度,均具有统计学意义(P0.05或P0.01)。由此得出,UC-MSCs能够通过IGF-Ⅰ介导JAK/STAT信号通路调节BMECs凋亡相关基因的表达,降低BMECs的凋亡率。 相似文献
10.
Ankyrin repeat and suppressor of cytokine signaling box-containing protein (ASB) 15 is a novel ASB gene family member predominantly expressed in skeletal muscle. We have previously reported that overexpression of ASB15 delays differentiation and alters protein turnover in mouse C(2)C(12) myoblasts. However, the extent of ASB15 regulation of differentiation and molecular pathways underlying this activity are unknown. The extracellular signal-regulated kinase (Erk) 1/2 and phosphatidylinositol-3 kinase-Akt (PI3K/Akt; Akt is also known as protein kinase B) signaling pathways have a role in skeletal muscle growth. Activation (phosphorylation) of the Erk1/2 signaling pathway promotes proliferation, whereas activation of the PI3K/Akt signaling pathway promotes myoblast differentiation. Accordingly, we tested the hypothesis that ASB15 controls myoblast differentiation through its regulation of these kinases. Stably transfected myoblasts overexpressing ASB15 (ASB15+) demonstrated decreased differentiation, whereas attenuation of ASB15 expression (ASB15-) increased differentiation. However, ASB15+ cells had less abundance of the phosphorylated mitogen-activated protein kinase (active) form, despite decreased differentiation relative to control myoblasts (ASB15Con). The mitogen-activated protein kinase kinase inhibitor, U0126, effectively decreased mitogen-activated protein kinase phosphorylation and stimulated differentiation in ASB15- and ASB15Con cells. However, inhibition of the Erk1/2 pathway was unable to overcome the inhibitory effect of overexpressing ASB15 on differentiation (ASB15+), suggesting that the Erk1/2 pathway is likely not the predominant mediator of ASB15 activity on differentiation. Expression of ASB15 also altered phosphorylation of the PI3K/Akt pathway, as ASB15+ and ASB15- cells had decreased and increased Akt phosphorylation, respectively. These data were consistent with observed differences in differentiation. Administration of IGF-I, a PI3K/Akt activator, in ASB15+ was able to partially override the previously observed phenotype of delayed differentiation, whereas administration of the PI3K/ Akt inhibitor, LY294002, decreased phosphorylation of Akt and differentiation of all cell lines similar to the untreated ASB15+ myoblasts. These results provide initial evidence that ASB15 has a role in early myoblast differentiation and that its effects may be mediated in part by the PI3K/Akt signal transduction pathway. 相似文献
11.
奶牛乳腺上皮细胞(BMECs)在奶牛泌乳期代谢旺盛,导致活性氧(ROS)大量产生,从而诱发氧化应激。辣木叶多糖(MLP)能有效清除ROS和自由基,但其是否具有缓解BMECs氧化损伤的潜力尚不清楚。因此,本文以MLP为添加剂,探究其对过氧化氢(H2O2)诱导BMECs氧化损伤的保护作用。本试验首先将分离的BMECs置于含有不同浓度H2O2的培养基中培养2 h建立氧化损伤模型,以确定H2O2的适宜浓度;随后在培养基中加入不同浓度MLP溶液培养BMECs 2 h,以确定MLP适宜浓度;最终选用浓度为500μmol/L的H2O2和4 mg/mL的MLP用于本试验。试验设置4个组,分别为对照组1(BMECs)、对照组2(BMECs+MLP)、损伤组(BMECs+H2O2)、保护组(BMECs+MLP+H2O2),每组3个重复。试验对BMECs中ROS数量、BMECs凋亡以及BMECs中过氧化氢酶(CAT)、谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量进行检测。结果表明:1)ROS检测结果显示,MLP抑制了细胞内ROS的生成。2)Hochest33258染色结果与透射电镜观察结果显示,MLP降低了BMECs的凋亡率,同时保持了细胞膜和细胞结构完整性。3)试剂盒检测结果显示,MLP提高了BMECs中CAT、GSH-Px和SOD活性,同时降低了MDA含量。综上所述,MLP可有效减缓BMECs凋亡,提高其抗氧化能力。 相似文献
12.
Using the MAC-T cell line as a model, the effects of insulin-like growth factor (IGF)-1 on the regulation of protein synthesis through the mammalian target of rapamycin complex 1 (mTORC1) signaling in bovine mammary epithelial cells were evaluated. Global rates of protein synthesis increased by 47% within 30 min of IGF-1 treatment. The effect of IGF-1 on protein synthesis was associated with enhanced association of the eukaryotic initiation factor (eIF) 4E with eIF4G and a concomitant reduction of eIF4E association with eIF4E-binding protein-1 (4E-BP1). There was a progressive increase in the phosphorylation state of ribosomal protein S6 kinase-1, a downstream target of mTORC1 in response to IGF-1. In addition, IGF-1 stimulated mTORC1 kinase activity toward 4E-BP1 in vitro. Phosphorylation on Ser473 of Akt was induced by IGF-1 within 5 min and remained elevated throughout a 30-min time course. The effect of IGF-1 on Akt phosphorylation was also concentration dependent. Activation of Akt by IGF-1 led to increased phosphorylation of tuberous sclerosis complex 2 on Thr1426, without any change in its association with tuberous sclerosis complex 1. Phosphorylation of proline-rich Akt substrate of 40-kDa (PRAS40) at Thr246 was stimulated by IGF-1. The amount of PRAS40 associated with mTORC1 decreased in response to IGF-1, and PRAS40 binding to mTORC1 was inversely related to its phosphorylation level. Overall, these results suggest that activation of the PI3K-Akt pathway by IGF-1 stimulated global protein synthesis in bovine mammary epithelial cells through changes in the phosphorylation and association state of components of the mTORC1 signaling pathway. 相似文献
13.
试验旨在探究奶牛乳腺上皮细胞（bovine mammary epithelial cells,BMECs）最佳的冻存液以改善乳腺上皮细胞的冻存质量。BMECs传至第5代后分别加入以下10种不同配方的冻存液。A组：85%DMEM＋10%胎牛血清＋5%DMSO;B组：80%DMEM＋10%胎牛血清＋10%DMSO;C组：75%DMEM＋10%胎牛血清＋15%DMSO;D组：70%DMEM＋10%胎牛血清＋20%DMSO;E组：85%DMEM＋5%胎牛血清＋10%DMSO;F组：75%DMEM＋15%胎牛血清＋10%DMSO;G组：70%DMEM＋20%胎牛血清＋10%DMSO;H组：80%DMEM＋10%胎牛血清＋10%甘油;I组：70%DMEM＋10%胎牛血清＋20%甘油;J组：60%DMEM＋10%胎牛血清＋30%甘油,冻存前统一调整细胞密度到1×106个/mL冻存。分别对复苏后的细胞进行台盼蓝染色计算存活率和PI/Hoechst33258双染计算凋亡率。结果表明,BMECs经不同冻存剂冻存复苏后,细胞活力、形态学及凋亡率表现有所不同,其中B组和G组的活力和24h贴壁率较其他组高,二者的凋亡率较低,二者之间差异无显著性（P〉0.05）;传代后B组细胞的生长状况最好。 相似文献
14.
Meimei Wang Yan Li Yanxia Gao Qiufeng Li Yufeng Cao Yizhao Shen Panliang Chen Jinling Yan Jianguo Li 《Reproduction in domestic animals》2021,56(8):1066-1084
High-yield dairy cows are usually subject to high-intensive cell metabolism and produce excessive reactive oxygen species (ROS). Once ROS is beyond the threshold of scavenging ability, it can induce oxidative stress, imperilling the reproductive performance of cows. The study was to investigate the effects of vitamin E (VE) on H2O2-induced proliferation and apoptosis of bovine granulosa cells and the underlying molecular mechanism. Granulosa cells were pretreated with VE for 24 hr and then treated with H2O2 for 6 hr. The results showed that VE treatment decreased the intracellular ROS levels, increased the MDA content, and improved the antioxidant enzyme activity in a dose-dependent manner. Furthermore, VE treatment promoted the proliferation and inhibited apoptosis in granulosa cells by up-regulation of CCND1 and BCL2 levels and down-regulation of P21, BAX, and CASP3 levels. The cytoprotective effects of VE were attributed to the activation of the NRF2 signalling pathway. Knockdown of the NRF2 impaired the cytoprotective effects of VE on granulosa cells. Besides, the PI3K/AKT and ERK1/2, but not the p38 signalling pathway is involved in the regulation of VE-mediated cell proliferation and apoptosis. The PI3K/AKT inhibitor LY294002 and ERK1/2 inhibitor SCH772984 inhibited the VE-induced granulosa cell proliferation and promoted apoptosis, whereas the p38 inhibitor SB203580 had the opposite effects. These results were confirmed by proliferation and apoptosis-related gene expression at mRNA and protein levels. The results also showed that the PI3K/AKT inhibitor LY294002 and ERK1/2 inhibitor SCH772984 inhibited VE-induced NRF2, GCLC, GCLM, and HO-1 expression, whereas the p38 inhibitor SB203580 not. Overall, the results demonstrated that VE-regulated granulosa cell proliferation and apoptosis via NRF2-mediated defence system by activating the PI3K/AKT and ERK1/2 signalling pathway. 相似文献
15.
Hyun Sun Cho Seung Hee Chang Youn Sun Chung Ji Young Shin Sung Jin Park Eun Sun Lee Soon Kyung Hwang Jung Taek Kwon Arash Minai Tehrani Minah Woo Mi Sook Noh Huda Hanifah Hua Jin Cheng Xiong Xu Myung Haing Cho 《Journal of veterinary science (Suw?n-si, Korea)》2009,10(1):23-28
Tetrandrine (TET), a bis-benzylisoquinoline alkaloid from the root of Stephania tetrandra, is known to have anti-tumor activity in various malignant neoplasms. However, the precise mechanism by which TET inhibits tumor cell growth remains to be elucidated. The present studies were performed to characterize the potential effects of TET on phosphoinositide 3-kinase/Akt and extracellular signal-regulated kinase (ERK) pathways since these signaling pathways are known to be responsible for cell growth and survival. TET suppressed cell proliferation and induced apoptosis in A549 human lung carcinoma cells. TET treatment resulted in a down-regulation of Akt and ERK phosphorylation in both time-/concentration-dependent manners. The inhibition of ERK using PD98059 synergistically enhanced the TET-induced apoptosis of A549 cells whereas the inhibition of Akt using LY294002 had a less significant effect. Taken together, our results suggest that TET: i) selectively inhibits the proliferation of lung cancer cells by blocking Akt activation and ii) increases apoptosis by inhibiting ERK. The treatment of lung cancers with TET may enhance the efficacy of chemotherapy and radiotherapy and increase the apoptotic potential of lung cancer cells. 相似文献
16.
It has been reported that phosphatidylinositol 3-kinase (PI3K)-protein kinase B (PKB) pathway plays a crucial role in the meiotic resumption and progression to the metaphase II (MII) stage of oocytes. However, the role of this pathway in meiotic arrest at the MII stage (cytostatic activity) is not well understood. In this study the effect of a PI3K inhibitor, LY294002, on the MAPK and p34cdc2 kinase activities of matured porcine oocytes was examined. After maturation culture, both the MAPK and p34cdc2 kinase activities in the oocytes were gradually decreased in a time-dependent manner. Although 25 µmol/L LY294002 did not affect either the MAPK or p34cdc2 kinase activities, 50 µmol/L LY294002 suppressed the PKB phosphorylation and slightly decreased MAPK activity, but not the p34cdc2 kinase activity. Therefore the effect of 10 µmol/L Ca2+ ionophore which was reported as inducing a transient decrease of p34cdc2 kinase but not MAPK activities, was also examined in LY294002-treated oocytes. By additional treatment with LY294002 after Ca2+ ionophore, both the MAPK and p34cdc2 kinase activities were decreased in a time-dependent manner, concomitantly with improvement of pronuclear formation. Therefore, we concluded that PI3K is involved in the maintenance of MAPK activity in matured porcine oocytes. 相似文献
17.
18.
Berenice L. Sanz Ressel Adriana R. Massone Claudio G. Barbeito 《Veterinary and comparative oncology》2019,17(4):522-527
Cutaneous papillomas (CP) are one of the most common skin neoplasms in dogs. Different murine models have shown that persistent activation of the phosphatidylinositol 3‐kinase/Akt/mammalian target of rapamycin (PI3K/Akt/mTOR) pathway has a central role in the development and progression of CP. The purpose of this study were to evaluate the immunohistochemical expression pattern of two key molecules involved in the PI3K/Akt/mTOR signalling pathway, pAktSer473, and pS6Ser235/236, on 36 canine specimens of CP using a tissue microarray. The results show that the PI3K/Akt/mTOR signalling pathway is persistently activated in CP of dogs, pointing to this pathway as a potential therapeutic target. 相似文献
19.
本试验旨在探讨催乳素对奶牛乳腺上皮细胞(BMECs)乳脂和乳蛋白合成相关基因表达的影响。选取中国荷斯坦奶牛BMECs为试验材料,经纯化培养后,培养基中添加不同浓度催乳素[0(对照)、100、300、500和1 000 ng/m L],继续培养24 h。通过四甲基偶氮唑盐(MTT)比色法检测细胞活力;利用试剂盒检测胞内甘油三酯的含量;采用实时定量PCR法检测乳脂和乳蛋白合成相关基因的表达。结果表明:1)催乳素浓度为100、300 ng/m L时,BMECs相对增殖率显著高于对照组与其他试验组(P0.05)。2)与对照组相比,300 ng/m L催乳素能够显著提高BM ECs乙酰辅酶A羧化酶(ACC)、二酰甘油酰基转移酶(DG AT)、脂肪酸结合蛋白3(FABP3)基因表达量及甘油三酯的含量(P0.05),硬脂酰辅酶A去饱和酶(SCD)、过氧化物酶体增殖物激活受体γ(PPARγ)基因表达量有增加的趋势。3)与对照组相比,100、300 ng/m L催乳素能够显著提高哺乳动物雷帕霉素靶蛋白(m TOR)、催乳素受体(PRLR)基因表达量(P0.05);300 ng/m L催乳素能显著提高αS1酪蛋白(CSN1 S1)基因表达量(P0.05)。综上所述,100~300 ng/m L的催乳素对BM ECs乳脂和乳蛋白合成有较好的促进效果。 相似文献
20.
Zhu L Ding X Zhu X Meng S Wang J Zhou H Duan Q Tao J Schifferli DM Zhu G 《Veterinary research》2011,42(1):57
ABSTRACT: Many viruses have been known to control key cellular signaling pathways to facilitate the virus infection. The possible involvement of signaling pathways in bovine herpesvirus type 1 (BoHV-1) infection is unknown. This study indicated that infection of MDBK cells with BoHV-1 induced an early-stage transient and a late-stage sustained activation of both phosphatidylinositol 3-kinase (PI3K)/Akt and mitogen activated protein kinases/extracellular signal-regulated kinase 1/2 (MAPK/Erk1/2) signaling pathways. Analysis with the stimulation of UV-irradiated virus indicated that the virus binding and/or entry process was enough to trigger the early phase activations, while the late phase activations were viral protein expression dependent. Biphasic activation of both pathways was suppressed by the selective inhibitor, Ly294002 for PI3K and U0126 for MAPK kinase (MEK1/2), respectively. Furthermore, treatment of MDBK cells with Ly294002 caused a 1.5-log reduction in virus titer, while U0126 had little effect on the virus production. In addition, the inhibition effect of Ly294002 mainly occurred at the post-entry stage of the virus replication cycle. This revealed for the first time that BoHV-1 actively induced both PI3K/Akt and MAPK/Erk1/2 signaling pathways, and the activation of PI3K was important for fully efficient replication, especially for the post-entry stage. 相似文献