大车前苷通过PI3K/Akt信号通路减轻大鼠肠缺血再灌注损伤

目的 探讨大车前苷通过PI3K/Akt信号通路减轻肠缺血再灌注损伤大鼠细胞凋亡的作用及机制.方法 24只SD大鼠随机分为正常对照组、缺血再灌注损伤组与大车前苷组,每组8只,在建模后大车前苷组灌胃给予大车前苷0.4g/kg.各组于再灌注3 h后,通过湿干重检测肠组织含水率;HE染色检测各组肠组织损伤情况;Western ...     

PI3K/Akt通路介导TRPV1抑制离体小鼠心脏缺血再灌注后的细胞凋亡

目的研究瞬时受体电位香草酸亚型1(TRPV1)对离体小鼠心脏缺血/再灌注(I/R)后心肌细胞凋亡的影响及与PI3K/Akt通路的关系。方法 TRPV1基因敲除(TRPV1~(-/-))和野生型(WT)小鼠各54只,均各随机分为假手术组(sham)、缺血再灌注组(I/R)和LY294002处理组(LY)。建立Langendorff离体心脏灌注模型,检测心功能;灌注结束后,TTC染色法检测心肌梗死面积;TUNEL法检测心肌细胞凋亡;Western blot检测Bcl-2、Bax、Akt和p-Akt的蛋白表达水平。结果 I/R后,TRPV1~(-/-)小鼠较WT小鼠的LVDP明显降低(P0.001),LVEDP明显升高(P0.001),同时心肌梗死面积和心肌凋亡细胞明显增加(P0.01),Bcl-2/Bax和p-Akt表达水平下降(P0.001)。LY294002阻断PI3K后,与相应的I/R组相比,WT小鼠心肌梗死面积明显扩大(P0.001),心肌凋亡细胞明显增加(P0.01),Bcl-2/Bax和p-Akt蛋白表达水平降低(P0.001)。结论 TRPV1可能通过PI3K/Akt通路抑制离体小鼠心脏缺血/再灌注所致的心肌细胞凋亡。     

Quercetin postconditioning attenuates myocardial ischemia/reperfusion injury in rats through the PI3K/Akt pathway

Quercetin (Que), a plant-derived flavonoid, has multiple benefical actions on the cardiovascular system. The current study investigated whether Que postconditioning has any protective effects on myocardial ischemia/reperfusion (I/R) injury in vivo and its potential cardioprotective mechanisms. Male Sprague-Dawley rats were randomly allocated to 5 groups (20 animals/group): sham, I/R, Que postconditioning, Que+{"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002 [a phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway inhibitor], and {"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002+I/R. I/R was produced by 30-min coronary occlusion followed by 2-h reperfusion. At the end of reperfusion, myocardial infarct size and biochemical changes were compared. Apoptosis was evaluated by both TUNEL staining and measurement of activated caspase-3 immunoreactivity. The phosphorylation of Akt and protein expression of Bcl-2 and Bax were determined by Western blotting. Que postconditioning significantly reduced infarct size and serum levels of creatine kinase and lactate dehydrogenase compared with the I/R group (all P<0.05). Apoptotic cardiomyocytes and caspase-3 immunoreactivity were also suppressed in the Que postconditioning group compared with the I/R group (both P<0.05). Akt phosphorylation and Bcl-2 expression increased after Que postconditioning, but Bax expression decreased. These effects were inhibited by {"type":"entrez-nucleotide","attrs":{"text":"LY294002","term_id":"1257998346","term_text":"LY294002"}}LY294002. The data indicate that Que postconditioning can induce cardioprotection by activating the PI3K/Akt signaling pathway and modulating the expression of Bcl-2 and Bax proteins.     

血必净通过激活PI3K/Akt/mTOR信号通路减轻大鼠睾丸缺血再灌注损伤

目的:探究血必净对缺血再灌注(I/R)损伤大鼠睾丸的保护作用及其相关机制。方法:45只雄性SD大鼠随机分为对照组、模型组、血必净低剂量组、血必净高剂量组和地塞米松组(均n=9);除对照组大鼠外,其它各组大鼠构建睾丸扭转复位模型,术后低、高剂量组及地塞米松组大鼠分别腹腔注射0.5和2 mL·kg^-1·d^-1血必净及0.5 mL·kg^-1·d^-1地塞米松。用药第3、7和14天取各组大鼠左侧睾丸,采用HE染色观察各组大鼠睾丸组织病理学改变;生化检测各组大鼠睾丸组织中丙二醛(MDA)、超氧化物歧化酶(SOD)、内皮素1(ET-1)和一氧化氮(NO)水平,Western blot检测各组大鼠睾丸组织中细胞周期相关蛋白、细胞凋亡相关蛋白以及PI3K/Akt/mTOR信号通路相关蛋白的水平。结果:血必净可显著减轻I/R大鼠睾丸损伤,显著升高I/R大鼠睾丸组织中SOD活性,降低MDA、ET-1和NO的含量,抑制I/R损伤组织中的氧化应激,介导细胞周期和细胞凋亡相关因子的表达,并显著升高I/R大鼠睾丸中p-PI3K、...     

白藜芦醇通过PI3K/Akt通路及线粒体途径抑制软骨肉瘤

 目的：探讨白藜芦醇抑制软骨肉瘤的机制及对线粒体途径和PI3K/Akt通路的影响。方法：SW1353软骨肉瘤细胞培养至对数生长期后设对照组和白藜芦醇处理组,药物处理组用25、50和100 μmol/L白藜芦醇处理24 h、48 h或72 h。采用CCK8法检测SW1353软骨肉瘤细胞的活力,Hoechst 33258荧光染色观察细胞凋亡,Western blotting检测activated caspase-3、Bcl-2、Bax、Akt和p-Akt蛋白在细胞中表达情况,细胞划痕实验观察细胞迁移情况。结果：白藜芦醇处理后细胞活力下降,呈时间-剂量依赖性（P<0.01）。Hoechst  33258染色检测可见药物处理组有明显的细胞凋亡核象。Western blotting检测显示药物处理组activated caspase-3和Bax蛋白表达上调,Bcl-2蛋白和p-Akt蛋白表达下调,总Akt改变不显著。细胞划痕试验显示,白藜芦醇能显著抑制SW1353细胞的迁移。结论：白藜芦醇能够诱导软骨肉瘤凋亡,部分是通过线粒体途径及PI3K/Akt信号通路发挥作用。     

丙泊酚对肝缺血再灌注大鼠肺损伤及PI3K/Akt通路的影响

 目的：通过研究丙泊酚对全肝缺血再灌注大鼠肺组织磷脂酰肌醇3-激酶/蛋白激酶B（PI3K/Akt）信号通路活化的影响,探讨丙泊酚在全肝缺血再灌注肺损伤中的作用机制。方法：SD 大鼠66只,随机分成4组,假手术组(S组,n=6)、肝缺血再灌注组 (IR 组,n=24)、丙泊酚预处理组 (P 组,n=24)和丙泊酚预处理+PI3K阻断剂 wortmannin 组 (P+W组,n=12),IR 组和 P 组按再灌注 1 h、3 h、6 h和12 h 分为 4 个亚组,P+W 组按再灌注 3 h和6 h分为 2 个亚组。S 组仅解剖肝门,不结扎;IR 组采用结扎肝蒂全肝缺血 30 min、再灌注的方法建立大鼠肝缺血再灌注模型;P 组缺血前 10 min 经尾静脉缓慢注射负荷剂量的丙泊酚 20 mg·kg-1,再以 20 mg·kg-1·h-1的速度尾静脉持续泵注直至处死,余同IR 组;P+W组缺血前经尾静脉注射 PI3K 阻断剂 wortmannin 15 μg·kg-1,余同 P 组。各组于再灌注 1 h、3 h、6 h和12 h时处死大鼠取肺组织。采用 Western  blotting 检测大鼠肺组织中总 Akt（t-Akt）、磷酸化 Akt（p-Akt)及 Bcl-2 蛋白表达水平;用 Annexin V-FITC/PI 法检测肺细胞凋亡率。结果：与 S 组比较,IR 组、P 组和 P+W 组肺组织中 p-Akt和 Bcl-2蛋白表达水平和肺细胞凋亡率升高（P<0.05）;与 IR 组比较,P 组 p-Akt 和 Bcl-2 蛋白表达水平升高,肺细胞凋亡率降低（P<0.05）,P+W 组上述指标表达差异无统计学意义（P>0.05）;与 P 组比较,P+W 组 p-Akt 和 Bcl-2蛋白表达水平下降,肺细胞凋亡率升高（P<0.05）;各组中 t-Akt 蛋白表达差异无统计学意义（P>0.05）。结论：丙泊酚可以减轻大鼠肝缺血再灌注诱发的肺损伤,其机制可能与 PI3K/Akt 信号通路的激活进而减轻肺细胞凋亡有关。     

脂多糖通过PI3K/Akt/mTOR通路调控巨噬细胞自噬*

 目的： 观察脂多糖对巨噬细胞自噬活化的影响及相关信号通路的探讨。方法: 体外培养巨噬细胞株RAW264.7,分为对照组、饥饿状态激活自噬组、单纯脂多糖（LPS）刺激组、LPS+PI3K抑制剂（hVps34）组和LPS+mTOR抑制剂（雷帕霉素）组。构建荧光真核表达载体pcDNA3.1-GFP-LC3,转染巨噬细胞,通过荧光显微镜观察各组细胞中自噬体形成情况。qRT-PCR方法检测各组中与细胞自噬相关的Atg5、Atg7、LC3-II和Bnip3 mRNA表达水平的改变。利用Western blotting检测LC3-II、p-Akt和p-mTOR蛋白在各组中的表达情况,以评价LPS激活巨噬细胞自噬的分子通路。结果: 成功构建稳定表达GFP-LC3的巨噬细胞,在荧光显微镜下可以观察到自噬在饥饿状态组、LPS+hVps34组和LPS+雷帕霉素组均有明显增强;qRT-PCR检测到Atg5、LC3-II和Bnip3 mRNA的表达在饥饿状态组、LPS+hVps34组和LPS+雷帕霉素组均有明显增强,而在LPS组中略微下降;Western blotting 检测发现p-Akt在饥饿状态组、LPS组和LPS+雷帕霉素组中表达明显升高;p-mTOR在饥饿状态组、LPS+hVps34组和LPS+雷帕霉素组表达明显下降;LC3-II的表达在饥饿状态组、LPS+hVps34组和LPS+雷帕霉素组中表达要高于对照组和LPS组。结论: LPS参与巨噬细胞自噬的调控,其可能的信号通路为PI3K/Akt/mTOR通路,但仍存在其它有效的调控通路。     

Cardioprotection induced by hydrogen sulfide preconditioning involves activation of ERK and PI3K/Akt pathways

We previously reported that hydrogen sulfide (H₂S) preconditioning (SP) produces cardioprotective effects against ischemia in rat cardiac myocytes. The present study aims to elucidate the signaling mechanisms involved in SP-induced cardioprotection by investigating the role of extracellular signal regulated kinase (ERK1/2) and phosphatidylinositol 3-kinase (PI3K)/Akt. We found that preconditioning with NaHS (a H₂S donor) for three cycles significantly decreased myocardial infarct size and improved heart contractile function in the isolated rat hearts. NaHS (1–100 μM) concentration-dependently increased cell viability and percentage of rod-shaped cardiac myocytes. Blockade of ERK1/2 with PD 98059 or PI3K/Akt with LY-294002 or Akt inhibitor III during either preconditioning or ischemia periods significantly attenuated the cardioprotection of SP, suggesting that both ERK1/2 and PI3K/Akt triggered and mediated the cardioprotection of SP. Moreover, SP induced ERK1/2 and Akt phosphorylation in isolated hearts. The phosphorylation of ERK1/2 induced by SP was attenuated by either glibenclamide, an ATP-sensitive K⁺ channel (K_ATP) blocker, or chelerythrine, a specific protein kinase C (PKC) blocker. In addition, ischemic-preconditioning-induced ERK1/2 activation was reversed by inhibiting endogenous H₂S production, suggesting that ERK1/2 activation induced by ischemic preconditioning was, at least partly, mediated by endogenous H₂S. In conclusion, K_ATP/PKC/ERK1/2 and PI3K/Akt pathways contributed to SP-induced cardioprotection.     

Alpha-crystallin promotes rat olfactory ensheathing cells survival and proliferation through regulation of PI3K/Akt/mTOR signaling pathways

Transplantation of cultured olfactory ensheathing cells (OECs) into lesions can promote axonal regeneration. However, the acutely injured CNS environment affects the survival and proliferation of OECs which might impair its therapy effects. To investigate whether α-crystallin can promote the survival and proliferation of OECs, OECs were cultured with α-crystallin. The survival of OECs was assessed by counting the numbers of p75-labeled OECs. Cellular proliferative activity was estimated by flow cytometry and quantification of BrdU-labeled cells. Phosphorylated p85, Akt and mammalian target of rapamycin (mTOR) were detected when OECs were culture for 7 days. Our results showed that the numbers of p75-labeled or Brdu-labeled OECs in α-crystallin group were much more than that in control group. And α-crystallin increased the phosphorylation of both p85, Akt and mTOR. LY294002 abrogated the ability of α-crystallin to phosphorylate Akt and mTOR, and decreased the percentage of cells in S and G2/M stage which were treated with α-crystallin. These findings indicated that α-crystallin positively regulated the activation of PI3K/Akt/mTOR signaling pathway and promote the proliferation and survival of cultured OECs.     

Adipophilin通过PI3K/Akt通路促进细胞内脂质蓄积

目的:探讨adipophilin促进细胞内脂质蓄积的可能机制,为动脉粥样硬化的防治提供参考。方法:分别通过q PCR、Western blot和油红O染色观察氧化型低密度脂蛋白(ox LDL)处理RAW264.7细胞不同时间后,细胞内Akt、p-Akt和adipophilin的蛋白水平及脂质蓄积情况;并检测PI3K/Akt抑制剂LY294002处理后,上述指标的变化;HEK293细胞过表达adipophilin后,检测Akt的活性;并用免疫共沉淀实验检测adipophilin与Akt之间的相互作用。结果:ox LDL处理细胞后,随着时间的延长,脂滴增多,Akt被活化,adipophilin表达增加,而LY294002处理则可抑制上述变化;过表达adipophilin后,p-Akt水平增高,但adipophilin与Akt之间未见直接相互作用。结论:Adipophilin可通过PI3K/Akt途径促进细胞内脂质蓄积,但可能不是通过直接相互关系发挥作用的。     

Intranasally delivered siRNA targeting PI3K/Akt/mTOR inflammatory pathways protects from aspergillosis

Innate responses combine with adaptive immunity to generate the most effective form of anti-Aspergillus immune resistance. Although some degree of inflammation is required for protection, progressive inflammation may worsen disease and ultimately prevents pathogen eradication. To define molecular pathways leading to or diverting from pathogenic inflammation in infection, we resorted to dendritic cells (DCs), known to activate distinct signaling pathways in response to pathogens. We found that distinct intracellular pathways mediated the sensing of conidia and hyphae by lung DCs in vitro, which translate in vivo in the activation of protective Th1/Treg responses by conidia or inflammatory Th2/Th17 responses by hyphae. In vivo targeting inflammatory (PI3K/Akt/mTOR) or anti-inflammatory (STAT3/IDO) DC pathways by intranasally delivered small interfering RNA (siRNA) accordingly modified inflammation and immunity to infection. Thus, the screening of signaling pathways in DCs through a systems biology approach may be exploited for the development of siRNA therapeutics to attenuate inflammation in respiratory fungal infections and diseases.     

ATP敏感性钾通道开放剂通过PI3K/Akt信号通路对缺血缺氧诱导PC12细胞凋亡发挥保护作用

目的 研究ATP敏感性钾通道(KATP)开放剂对缺血缺氧诱导PC12细胞凋亡及Akt蛋白和mRNA表达的影响.探讨KATP开放剂的保护作用机制.方法 取传代后3d Pc12细胞,分为对照组,缺血缺氧组,KATP通道开放剂组,KATP通道开放剂+阻断剂组.采用Annexin-v FITC/PI双染流式细胞分析仪检测凋亡率...     

Anti-apoptotic PI3K/Akt signaling by sodium/glucose transporter 1 reduces epithelial barrier damage and bacterial translocation in intestinal ischemia

Intestinal ischemia/reperfusion (I/R) causes mucosal barrier damage and bacterial translocation (BT), leading to septic complications. Previous in vitro studies showed that activation of sodium/glucose transporter 1 (SGLT1) prevented the epithelial apoptosis and permeability rise induced by microbial products. Our aim was to investigate whether luminal glucose uptake by SGLT1 protects against ischemia-induced epithelial cell death and barrier dysfunction, and to explore the glucose-mediated cellular survival pathways in vivo. Rat jejunum was luminally instilled with either vehicle, a pancaspase inhibitor ZVAD, or glucose prior to I/R challenge (occlusion of the superior mesenteric artery for 20?min and reperfusion for 60?min). Histopathology and apoptosis in the jejunum were examined by TUNEL staining and caspase-3 cleavage. Intestinal permeability was evaluated using in vivo assays measuring luminal-to-blood passage of fluorescein-dextran and portal drainage of enterally administered gadodiamide by magnetic resonance imaging. BT was determined by culturing liver and spleen homogenates. Immunofluorescent analysis and kinase assay were used to study PI3K/Akt signaling pathways. Intestinal I/R caused enterocyte apoptosis and villous destruction. Intestinal infusion with ZVAD decreased the I/R-triggered gut permeability rise and BT, suggesting that the barrier damage was partly dependent on cell apoptosis. Enteral instillation of glucose attenuated the epithelial apoptosis, barrier damage, and mucosal inflammation caused by I/R. Phloridzin (a SGLT1 inhibitor) reduced the protective effect of glucose in a dose-dependent manner. Enteral glucose increased the mucosal Akt kinase activity as evidenced by the augmented phosphorylation of exogenous GSK3. Enhanced membrane translocation and phosphorylation of Akt in epithelial cells were associated with elevated phosphorylation of mTOR, Bad, and FoxO1/3a following glucose uptake. Inhibition of PI3K/Akt signaling by LY294002 and wortmannin partially blocked the glucose-mediated rescue of cell apoptosis and barrier damage. In conclusion, SGLT1 glucose uptake alleviated I/R-induced barrier dysfunction and BT, partly by inhibiting epithelial apoptosis via activation of PI3K/Akt signaling.     

Insulin regulates Presenilin 1 localization via PI3K/Akt signaling

Recently, insulin signaling has been highlighted in the pathology of Alzheimer's disease (AD). Although the association between insulin signaling and Tau pathology has been investigated in several studies 0065, 0110 and 0115, the interaction between insulin signaling and Presenilin 1 (PS1), a key molecule of amyloid β (Aβ) pathology, has not been elucidated so far. In this study, we demonstrated that insulin inhibited PS1 phosphorylation at serine residues (serine 353, 357) via phosphatidylinositol 3-kinase (PI3K)/Akt signal pathway and strengthened the trimeric complex of PS1/N-cadherin/β-catenin, consequently relocalizing PS1 to the cell surface. Since our recent report suggests that PS1/N-cadherin/β-catenin complex regulates Aβ production [28], it is likely that insulin signaling affects Aβ pathology by regulating PS1 localization.     

紫草素通过PI3K/Akt通路抑制氧糖剥夺诱导的大鼠原代皮层神经元凋亡

目的:探讨紫草素对氧糖剥夺(OGD)损伤模型中大鼠原代皮层神经元的作用及机制。方法:用不同浓度(0. 02、0. 2、2和20μmol/L)紫草素对大鼠原代皮层神经元经进行预处理,再经OGD损伤处理,用乳酸脱氢酶(LDH)释放法和荧光素二乙酸酯/碘化丙啶(FDA/PI)双染法分别检测神经元活性和凋亡情况,选择最适紫草素浓度。然后,在加入紫草素之前提前加入LY294002(PI3K/Akt信号通路抑制剂,1μmol/L),用Wesern blot法检测神经元p-Akt(Ser473)水平变化,用LDH法和FDA/PI双染法检测神经元活性和凋亡率变化。结果:0. 2、2及20μmol/L的紫草素可显著提高神经元存活率(P 0. 05),同时还可使神经元内p-Akt(Ser473)水平显著升高(P 0. 05); LY294002可显著阻断紫草素对神经元p-Akt(Ser473)水平和凋亡率的影响(P 0. 05)。结论:紫草素可通过激活PI3K/Akt通路来减少OGD诱导的大鼠原代皮层神经元凋亡。     

Picroside II protects cardiomyocytes from hypoxia/reoxygenation-induced apoptosis by activating the PI3K/Akt and CREB pathways

Picroside II, an iridoid glucoside found in the root of Picrorhiza scrophulariiflora Pennell (Scrophulariaceae), has been demonstrated to reduce apoptosis in neuronal cells and other cell types. However, whether picroside II has a protective effect against cardiomyocyte apoptosis is poorly understood. In the present study, we investigated the cardioprotective role of picroside II and the underlying mechanisms in hypoxia/reoxygenation-induced cardiomyocyte apoptosis. The pretreatment with picroside II markedly attenuated hypoxia/reoxygenation-induced cell damage dose-dependently, which was evident by the increased cell viability and the corresponding decrease in lactate dehydrogenase release (LDH). The pretreatment with picroside II inhibited apoptosis confirmed by Annexin V-FITC staining, Hoechst 33258 nuclear staining and by assessment of caspase-3 activity. In addition, we found that picroside II not only increased the expression of Bcl-2, while decreasing Bax expression, but also augmented Akt and cAMP response element-binding protein (CREB) phosphorylation and ultimately inhibited hypoxia/reoxygenation-induced apoptosis. Furthermore, the protective effects of picroside II were abrogated by pretreatment of the cells with wortmannin or LY294002, a specific PI3K inhibitor. The present study suggests that picroside II inhibits hypoxia/reoxygenation-induced apoptosis in cardiomyocytes by activating the PI3K/Akt and CREB pathways and modulating expression of Bcl-2 and Bax.     

SASH1 inhibits proliferation and invasion of thyroid cancer cells through PI3K/Akt signaling pathway

The SASH1 (SAM- and SH3-domain containing 1) gene, a member of the SLY-family of signal adapter proteins, has an important regulatory role in tumorigenesis, but its implication in thyroid carcinoma has not been yet investigated. In this study, we investigated the role of SASH1 in proliferation and invasion of thyroid cancer cells and the underlying mechanism. Our results demonstrated that SASH1 is down-regulated in thyroid cancer cells. Overexpression of SASH1 inhibits thyroid cancer cell proliferation, migration and invasion with decreased epithelial-mesenchymal transition (EMT). Mechanistically, overexpression of SASH1 inhibits thyroid cancer cell proliferation and invasion through down-regulation of PI3K and Akt phosphorylation. Taken together, the present study showed that the loss or inhibition of SASH1 expression may play an important role in thyroid cancer development, invasion, and metastasis and that SASH1 may be a potential therapeutic target for the treatment of thyroid cancer.     

参芎化瘀胶囊通过磷脂酰肌醇激酶/蛋白激酶B信号通路抑制全脑缺血大鼠神经细胞凋亡

目的:探讨参芎化瘀胶囊对大鼠脑缺血/再灌注损伤神经细胞凋亡的影响.方法:雄性SD大鼠被分成假手术组,模型组,参芎化瘀胶囊高、低剂量组,以改良的Pulsineli 4血管阻断(4-VO)法制作全脑缺血模型.免疫组织化学法检测海马区磷脂酰肌醇3-激酶(PI3-K)、蛋白激酶B(PKB/Akt)的表达.原位缺口末端标记法(TUNEL)检测凋亡细胞.结果:与假手术组比较,模型组中PI3-K、Akt表达增高,凋亡神经细胞数量增多;与模型组比较,参芎化瘀胶囊组中PI3-K、Akt表达进一步增多,凋亡神经细胞数量减少,上述变化在高剂量参芎化瘀胶囊组更为明显.结论:参芎化瘀胶囊可抑制全脑缺血大鼠神经细胞凋亡,其机制与PI3-K/Akt信号通路有关.     

Ang II attenuates IGF-1-stimulated Na+, K(+)-ATPase activity via PI3K/Akt pathway in vascular smooth muscle cells

We have investigated the role of phosphatidylinositol 3-kinase (PI3K) and serine/threonine protein kinase B (Akt) in mediating vascular smooth muscle cells (VSMC) sodium pump (Na+, K(+)-ATPase) regulatory interactions between insulin-like growth factor-1 (IGF-1) and angiotensin II (Ang II). Treatment with IGF-1 (100 nM) for 30 min or Ang II (100 nM) for 10 min increased sodium pump activity. Pretreatment with Ang II for 10 min, abolished IGF-1 increased sodium pump activity. Given separately for 6 h, Ang II and IGF-1 stimulated alpha1 mRNA accumulation. Phosphorylation on Ser473 of Akt was increased after treatment with both IGF-1 and Ang II. Pretreatment with 100 nM of PI3K inhibitor Wortmannin (WT) for 30 min decreased: IGF-1 and Ang II-stimulated pump activity, phosphorylation of Akt and PI3K protein expression. Pretreatment with Ang II attenuated IGF-1-stimulated sodium pump activity, phosphorylation of Akt and PI3K protein expression. IGF-1 increased the association between IRS-1 and p85, and Ang II as well as PI3K inhibition decreased this IGF-1 effect. These results suggest that Ang II, which increases pump activity alone, reduces the IGF-1 stimulation of sodium pump activity by attenuating PI3K/Akt signaling. These results implicate PI3K/Akt pathways in Ang II/IGF-1 regulation of the sodium pump in VSMC.