Fibroblast growth factor 2 decreases bleomycin‐induced pulmonary fibrosis and inhibits fibroblast collagen production and myofibroblast differentiation

Fibroblast growth factor (FGF) signaling has been implicated in the pathogenesis of pulmonary fibrosis. Mice lacking FGF2 have increased mortality and impaired epithelial recovery after bleomycin exposure, supporting a protective or reparative function following lung injury. To determine whether FGF2 overexpression reduces bleomycin‐induced injury, we developed an inducible genetic system to express FGF2 in type II pneumocytes. Double‐transgenic (DTG) mice with doxycycline‐inducible overexpression of human FGF2 (SPC‐rtTA;TRE‐hFGF2) or single‐transgenic controls were administered intratracheal bleomycin and fed doxycycline chow, starting at either day 0 or day 7. In addition, wild‐type mice received intratracheal or intravenous recombinant FGF2, starting at the time of bleomycin treatment. Compared to controls, doxycycline‐induced DTG mice had decreased pulmonary fibrosis 21 days after bleomycin, as assessed by gene expression and histology. This beneficial effect was seen when FGF2 overexpression was induced at day 0 or day 7 after bleomycin. FGF2 overexpression did not alter epithelial gene expression, bronchoalveolar lavage cellularity or total protein. In vitro studies using primary mouse and human lung fibroblasts showed that FGF2 strongly inhibited baseline and TGFβ1‐induced expression of alpha smooth muscle actin (αSMA), collagen, and connective tissue growth factor. While FGF2 did not suppress phosphorylation of Smad2 or Smad‐dependent gene expression, FGF2 inhibited TGFβ1‐induced stress fiber formation and serum response factor‐dependent gene expression. FGF2 inhibition of stress fiber formation and αSMA requires FGF receptor 1 (FGFR1) and downstream MEK/ERK, but not AKT signaling. In summary, overexpression of FGF2 protects against bleomycin‐induced pulmonary fibrosis in vivo and reverses TGFβ1‐induced collagen and αSMA expression and stress fiber formation in lung fibroblasts in vitro, without affecting either inflammation or epithelial gene expression. Our results suggest that in the lung, FGF2 is antifibrotic in part through decreased collagen expression and fibroblast to myofibroblast differentiation. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.     

Icariin improves the sexual function of male mice through the PI3K/AKT/eNOS/NO signalling pathway

We aimed to investigate the effect and mechanism of icariin on male sexual function. Forty‐eight Crl:CD1(ICR) male mice were randomly divided into control, low‐, medium‐ and high‐dose icariin group (intragastric administration of 50, 100 and 200 mg/kg/d for 21 days). Mating experiment was then performed at a ratio of 1: 3 (male: female). The mating behaviours of male mice were recorded. The genital indexes and serum testosterone, nitric oxide (NO), hypothalamic dopamine (DA) and 5‐ hydroxy tryptophan (5‐HT) concentrations were measured. The expression of endothelial nitric oxide (eNOS), phosphatidylinositol tallow alcohol 3‐kinase (PI3K) and phosphorylated protein kinase (p‐AKT) in penile tissue was detected by Western blot. All icariin groups exhibited shorter capture latency and ejaculation latency, increased number of capture and ejaculation, higher capture and ejaculation rate, and higher testicular and prostate indexes compared with controls (p < .001). These groups had higher serum testosterone and NO concentrations (p < .001), hypothalamic DA and 5‐HT levels, and eNOS, PI3K and phosphorylated AKT expressions in penile tissue (p < .05). The effect of icariin was dose‐dependently increased. Our study suggests that icariin improves the sexual function of male mice, which might be associated with the hypothalamic–pituitary–gonadal axis and the PI3K/AKT/eNOS/NO signalling pathway.     

Molecular determinants of the physiological adaptation to stress in the cardiomyocyte: a focus on AKT

Cardiomyocytes (CMCs) adapt to physiological or pathological stimuli by undergoing molecular changes which differentiate according to the specificity of the stimulus and eventually generate a phenotype with peculiar molecular characteristics. Here, we review the literature on the molecular mechanisms activated in the CMC during physiologic adaptation to stress, as opposed to maladaptation. The critical role of the IGF-1 receptor/PI3K/Akt signaling pathway during this process is described, including effector targets regulating inotropism and cell size.     

Insulin like growth factor-1 increases fatty liver preservation in IGL-1 solution

AIM: To investigate the benefits of insulin like growth factor-1 (IGF-1) supplementation to serum-free institut georges lopez-1 (IGL-1) solution to protect fatty liver against cold ischemia reperfusion injury. METHODS: Steatotic livers were preserved for 24 h in IGL-1  solution supplemented with or without IGF-1 and then perfused "ex vivo " for 2 h at 37℃. We examined the effects of IGF-1 on hepatic damage and function (transaminases, percentage of sulfobromophthalein clearance in bile and vascular resistance). We also studied other factors associated with the poor tolerance of fatty livers to cold ischemia reperfusion injury such as mitochondrial damage, oxidative stress, nitric oxide, tumor necrosis factor-α (TNF-α) and mitogen-activated protein kinases.RESULTS: Steatotic livers preserved in IGL-1 solutionsupplemented with IGF-1 showed lower transaminase levels, increased bile clearance and a reduction in vascular resistance when compared to those preserved in IGL-1solution alone. These benefits are mediated by activation of AKT and constitutive endothelial nitric oxide synthase (eNOS), as well as the inhibition of inflammatory cytokines such as TNF-α. Mitochondrial damage and oxidative stress were also prevented.CONCLUSION: IGL-1  enrichment with IGF-1 increasedfatty liver graft preservation through AKT and eNOS activation, and prevented TNF-α release during normothermic reperfusion.     

葛根素通过PI3K/Akt途径对大鼠缺血再灌注心肌细胞凋亡的抑制

目的 观察葛根素预处理对缺血再灌注(I/R)大鼠心肌细胞凋亡的影响及其与PI3K/Akt信号通路的关系.方法 30只SD大鼠随机分为假手术组(SH组)、缺血再灌注组(I/R组)、葛根素预处理组(PU组)、葛根素预处理+LY294002组(PU+ LY组)及缺血再灌注+LY294002组(I/R+ LY组).除假手术组外,其他各组大鼠均行结扎冠状动脉前降支30 min,再灌注120 min,监测血流动力学,Western印迹法检测心肌组织p-Akt信号蛋白的表达;TUNEL法检测心肌细胞凋亡.结果 与I/R组比较,PU组能够明显改善心功能,抑制心肌细胞凋亡,并增加Akt的磷酸化水平(P<0.05,P<0.01).结论 葛根素预处理能够抑制缺血再灌注所致的心肌细胞凋亡,其作用机制与PI3K/Akt信号通路活化有关.     

AKT2及磷酸化AKT2在非小细胞肺癌中的表达及临床意义

目的 研究AKT2及磷酸化AKT2(p-AKT2)在非小细胞肺癌(NSCLC)组织中的表达及临床意义.方法 应用免疫组织化学法检测137例非小细胞肺癌组织中AKT2和p-AKT2表达,分析AKT2及p-AKT2表达与肺癌预后的关系.结果 非小细胞肺癌组织中AKT2在腺癌及鳞癌组织中的阳性表达率分别为60.5%和54.1%,差异无统计学意义(P>0.05);p-AKT2在腺癌及鳞癌组织中的阳性表达率分别为68.4%和47.5%,差异有统计学意义(P<0.05).同时,本研究发现AKT2和p-AKT2的表达在患者的年龄、性别、肿瘤TNM分期及细胞分化程度等方面差异无统计学意义(P>0.05).生存分析显示,AKT2表达阳性的NSCLC患者5年生存率及中位生存时间与阴性表达者比较差异无统计学意义[36%vs.30%,(33.960±2.485)月vs.(31.338±2.868)月,P>0.05];而p-AKT2表达阳性的患者5年生存率及中位生存时间与阴性表达者比较差异有统计学意义[20%vs.56%,(28.464±2.235)月vs.(39.214±3.075)月,P<0.05].进一步分层分析发现,Ⅰ期NSCLC患者中,AKT2表达阳性者5年中位生存时间与阴性表达者比较差异无统计学意义[(34.778±4.469)月va.(40.133±5.632)月,P>0.05];而p-AKT2表达阳性的NSCLC患者5年中位生存时间与阴性表达者比较差异有统计学意义[(29.808±4.337)月vs.(47.875±4.852)月,P<0.05].结论 p-AKT2在肺腺癌中的表达高于肺鳞癌,且p-AKT2的阳性表达缩短了NsCLC患者的5年中位生存时间.     

Gallic acid inhibits migration and invasion in human osteosarcoma U-2 OS cells through suppressing the matrix metalloproteinase-2/-9, protein kinase B (PKB) and PKC signaling pathways

Advanced cancer is a multifactorial disease which complicates treatment if the cancer cells have metastasized calling for the targeting of multiple cellular pathways. Gallic acid (GA) is known to possess multiple pharmacological activity including antitumor effects. This study investigated the mechanisms for the anticancer properties of GA on migration and invasion of human osteosarcoma U-2 OS cells. The migration and invasion in U-2 OS cells were determined by a Boyden chamber transwell assay. The expression levels and activities of MMP-2 and MMP-9 were measured by Western blotting, real-time PCR and gelatin zymography assays. All examined proteins levels from Western blotting indicated that GA decreased the protein levels of GRB2, PI3K, AKT/PKB, PKC, p38, ERK1/2, JNK, NF-κB p65 in U-2 OS cells. GA also inhibited the activities of AKT, IKK and PKC by in vitro kinase assay. GA suppressed the migration and invasive ability of U-2 OS cells, and it decreased MMP-2 and MMP-9 protein and mRNA levels and secreted enzyme activities in vitro. These results suggest that potential signaling pathways of GA-inhibited migration and invasion in U-2 OS cells may be due to down-regulation of PKC, inhibition of mitogen-activated protein kinase (MAPK) and PI3K/AKT, resulting in inhibition of MMP-2 and MMP-9 expressions.     

游离脂肪酸及葡萄糖对鼠主动脉内皮细胞的影响及作用机制

目的探讨高糖高游离脂肪酸（freefattyacids,FFAs）对内皮细胞增殖和凋亡的影响及其作用机制。方法原代培养大鼠主动脉内皮细胞（rataortaendothelialcell,RAEC）,采用不同浓度的葡萄糖（5．5mmol／L,30mmol／L）及棕榈酸（200μmol／L、400μmol／L、600μmol／L）单独或联合作用于细胞24h、48h、72h。免疫组织化学染色方法鉴定内皮细胞并测定IL-8、Bcl-2、BAX表达水平：MTT比色法检测细胞增殖率。结果FFAs及葡萄糖单独及联合应用均可导致细胞出现凋亡形态学变化,增殖呈剂量-时间依赖性（P〈0．05）,且联合组明显低于单独培养组（P〈0．01）;干预后IL-8、BAX表达增加,Bcl-2蛋白表达逐渐减弱,Bcl-2／BAX比值逐渐减小,联合培养组表达更为明显。结论高浓度FFAs及高糖具有抑制内皮细胞生长、促进其凋亡的作用,其作用机制可能是通过葡萄糖及棕榈酸酯参与P13K／AKT等途径激活氧化应激诱导细胞凋亡。     

胃癌组织中蛋白激酶B和表皮生长因子受体的表达及其临床意义

目的观察胃癌组织中蛋白激酶B(PKB/AKT)和表皮生长因子受体(EGFR)的表达情况并探讨其与胃癌的临床病理特征之间的相关性。方法选取76例胃癌患者癌组织及癌旁正常胃组织,通过免疫组化法检测组织中PKB/AKT和EGFR的表达水平,分析其与患者的临床病理特征之间的相关性。结果胃癌组织中PKB/AKT和EGFR的表达水平与患者的性别、年龄,肿瘤的病理类型、分化程度均无明显相关性(P>0.05);而胃癌组织中PKB/AKT的表达水平与肿瘤大小、T分期、TNM分期存在正相关(P<0.05);EGFR水平与TNM分期存在正相关(P<0.05)。出现淋巴结转移及远处转移患者的胃癌组织中PKB/AKT、EGFR表达水平较无转移者高(P<0.05)。结论胃癌组织中PKB/AKT和EGFR的的表达与肿瘤的大小、分期及转移情况存在一定的相关性,对胃癌的诊断、疾病的分期及生物学行为的判断有重要的参考意义。