Loss of IκB kinase β promotes myofibroblast transformation and senescence through activation of the ROS-TGFβ autocrine loop

Using forward and reverse genetics and global gene expression analyses, we explored the crosstalk between the IκB kinase β (IKKβ) and the transforming growth factor β (TGFβ) signaling pathways. We show that in vitro ablation of Ikkβ in fibroblasts led to progressive ROS accumulation and TGFβ activation, and ultimately accelerated cell migration, fibroblast-myofibroblast transformation and senescence. Mechanistically, the basal IKKβ activity was required for anti-oxidant gene expression and redox homeostasis. Lacking this activity, IKKβ-null cells showed ROS accumulation and activation of stress-sensitive transcription factor AP-1/c-Jun. AP-1/c-Jun activation led to up-regulation of the Tgfβ2 promoter, which in turn further potentiated intracellular ROS through the induction of NADPH oxidase (NOX). These data suggest that by blocking the autocrine amplification of a ROS-TGFβ loop IKKβ plays a crucial role in the prevention of fibroblast-myofibroblast transformation and senescence.

BM-MSCs from Wuzhishan mini-pigs delay the progress of renal fibrosis induced by chronic kidney disease through autocrine hepatocyte growth factor in vitro / 中南大学学报(医学版)

To isolate bone marrow mesenchymal stem cells (BM-MSCs) and establish the model of chronic kidney disease (CKD) of Wuzhishan (WZS) mini-pig, and to study the repairment effect of BM-MSCs on CKD-induced renal fibrosis in vitro.
 Methods: Density gradient method was used to isolate and culture BM-MSCs. The cells were verified by morphology, phenotype, differentiation and so on. The left partial ureteral obstruction (LPUUO) was used to establish the CKD model, which was evaluated by B-ultrasound, single-photon emission computed tomography (SPECT), HE and Masson staining. The cells were divided into 3 groups, the tissue plus BM-MSCs group, the tissue group, and the BM-MSCs group, respectively. Seven days later, the supernatants were collected to observe the changes of hepatocyte growth factor (HGF) cumulative release. HE and Masson staining was used to observe the changes of renal tissue.
 Results: The isolated BM-MSCs possessed the features as follow: fibroblast-like adherent growth; positive in CD29 and CD90 expression while negative in CD45 expression; osteogenic induction and alizarin red staining were positive; alcian blue staining were positive after chondrogenic induction. Twelve weeks after the operation of LPUUO, B-ultrasound showed the thin renal cortical with pelvis effusion; SPETCT showed the left kidney delayed filling and renal impairment. The accumulation of HGF in the tissue plus BM-MSCs group was significantly higher than that in the tissue alone group at the 1st, 5th, 6th, 7th day, respectively (P<0.05). HE staining showed the different degree of renal lesions between the tissue plus BM-MSCs+CKD group and the tissue alone group, which was aggravated with the time going. Masson staining showed that the cumulative optical density of blue-stained collagen fibers in tissue plus BM-MSCs group was significantly lower than that in the tissue group at the 5th to 7th day (P<0.05).
 Conclusion: BM-MSCs from WZS mini-pig can inhibit or delay the progress of CKD-induced renal fibrosis through autocrine HGF in vitro.

Platelet-derived growth factor signaling in human malignancies / 癌症

Platelet-derived growth factors (PDGFs) and their receptors were identified and purified decades ago. PDGFs are important during normal development and in human cancers. In particular, autocrine PDGF signaling has been implicated in various types of malignancies such as gliomas and leukemia. In contrast, paracrine signaling was found in cancers that originate from epithelial cells, where it may be involved in stromal cell recruitment, metastasis, and epithelial-mesenchymal transition. This editorial briefly discusses autocrine and paracrine PDGF signaling and their roles in human cancers, and introduces a series of review articles in this issue that address the possible roles of PDGFs in various processes involved in different types of cancers.

Serglycin in human cancers / 癌症

Serglycin belongs to a family of small proteoglycans with Ser-Gly dipeptide repeats, and it is modified with different types of glycosaminoglycan side chains. Intracellular serglycin affects the retention and secretion of proteases, chemokines, or other cytokines by physically binding to these factors in secretory granules. Extracellular serglycin has been found to be released by several types of human cancer cells, and it is able to promote the metastasis of nasopharyngeal carcinoma cells. Serglycin can bind to CD44, which is another glycoprotein located in cellular membrane. Serglycin's function of promoting cancer cell metastasis depends on glycosylation of its core protein, which can be achieved by autocrine as well as paracrine secretion mechanisms. Further investigations are warranted to elucidate serglycin signaling mechanisms with the goal of targeting them to prevent cancer cell metastasis.

Platelet-derived growth factor receptor alpha in glioma: a bad seed / 癌症

Recent collaborative, large-scale genomic profiling of the most common and aggressive brain tumor glioblastoma multiforme(GBM) has significantly advanced our understanding of this disease. The gene encoding platelet-derived growth factor receptor alpha(PDGFRα) was identified as the third of the top 11 amplified genes in clinical GBM specimens. The important roles of PDGFRα signaling during normal brain development also implicate the possible pathologic consequences of PDGFRα over-activation in glioma. Although the initial clinical trials using PDGFR kinase inhibitors have been predominantly disappointing, diagnostic and treatment modalities involving genomic profiling and personalized medicine are expected to improve the therapy targeting PDGFRα signaling. In this review, we discuss the roles of PDGFRαsignaling during development of the normal central nervous system(CNS) and in pathologic conditions such as malignant glioma. We further compare various animal models of PDGF-induced gliomagenesis and their potential as a novel platform of pre-clinical drug testing. We then summarize our recent publication and how these findings will likely impact treatments for gliomas driven by PDGFRα overexpression. A better understanding of PDGFRα signaling in glioma and their microenvironment, through the use of human or mouse models, is necessary to design a more effective therapeutic strategy against gliomas harboring the aberrant PDGFRα signaling.

Epigallocatechin-3-gallate inhibits paracrine and autocrine hepatocyte growth factor/scatter factor-induced tumor cell migration and invasion

Aberrant activation of hepatocyte growth factor/scatter factor (HGF/SF) and its receptor, Met, is involved in the development and progression of many human cancers. In the cell-based screening assay, (-)epigallocatechin-3-gallate (EGCG) inhibited HGF/SF-Met signaling as indicated by its inhibitory activity on HGF/SF-induced cell scattering and uPA activation (IC50 = 15.8 microg/ml). Further analysis revealed that EGCG at low doses specifically inhibited HGF/SF-induced tyrosine phosphorylation of Met but not epidermal growth factor (EGF)-induced phosphorylation of EGF receptor (EGFR). On the other hand, high-dose EGCG decreased both Met and EGFR proteins. We also found that EGCG did not act on the intracellular portion of Met receptor tyrosine kinase, i.e., it inhibited InlB-dependent activation of Met but not NGF-induced activation of Trk-Met hybrid receptor. This inhibition decreased HGF-induced migration and invasion by parental or HGF/SF-transfected B16F10 melanoma cells in vitro in either a paracrine or autocrine manner. Furthermore, EGCG inhibited the invasion/metastasis of HGF/SF-transfected B16F10 melanoma cells in mice. Our data suggest the possible use of EGCG in human cancers associated with dysregulated paracrine or autocrine HGF/SF-Met signaling.

Autocrine effect of vascular endothelial growth factor on the proliferation of HaCaT cells / 浙江大学学报·医学版

<p><b>OBJECTIVE</b>To determine the autocrine effect of vascular endothelial growth factor (VEGF) on epidermal keratinocytes HaCaT cells.</p><p><b>METHODS</b>Cultured HaCaT cells were treated with various concentrations of VEGF(165) (0,1,5,10,25,50,100 ng/ml) or Avastin (0,0.063,0.125,0.25,0.50,1.0,2.0 mg/ml) in vitro. HaCaT cell proliferation was determined by MTT assay and the cell migration was measured by migration assay. The effect of VEGF(165) (10 ng/ml) on phosphorylation of ERK1/2 was detected in HaCaT cells pretreated or not pretreated with Avastin (0.5 mg/ml).</p><p><b>RESULTS</b>VEGF enhanced the proliferation and migration of HaCaT cells in a dose-dependent manner, while Avastin inhibited the effects of VEGF also in a dose-dependent manner. VEGF(165) (10 ng/ml) induced the phosphorylation of ERK1/2 in HaCaT cells,but which was blocked by Avastin (0.5 mg/ml).</p><p><b>CONCLUSION</b>VEGF enhanced the proliferation and migration of HaCaT cells in a dose-dependent manner, while Avastin inhibited the effects of VEGF also in a dose-dependent manner. VEGF(165) (10 ng/ml) induced the phosphorylation of ERK1/2 in HaCaT cells,but which was blocked by Avastin (0.5 mg/ml).</p>

Regulatory effect of Ningxin Hongqi Capsule on local ovarian autocrine and paracrine factors in rats during peri-menopausal period / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To explore the regulatory effect and mechanism of Ningxin Hongqi Capsule on local ovarian autocrine and paracrine factors in peri-menopausal rats.</p><p><b>METHODS</b>SD female rats aged 4 months were allocated in a normal control group (A) and those aged 14 months with vagino-cytologic figure of oestrus elongation were allocated in a senile female rat model group (B). Rats in Group B were subdivided into 5 groups randomly as the B1, B2 and B3 subgroups treated respectively with high, moderate and low dose Ningxin Hongqi Capsule, the B4 subgroup treated with estradiol and the B5 subgroup untreated for control. Rats' ovaries were obtained at the end of the experiment for observing the conditions of ovarian growing follicles and corpus luteum by HE staining, determining expressions of ovarian estradiol receptor (ER), progesterone receptor (PR), follicle-stimulating hormone (FSH), luteinizing hormone (LH), inhibin alpha (INHalpha), activin (ACT) alpha-beta, follistatin (FS), and insulin-like growth factor (IGF-1).</p><p><b>RESULTS</b>As compared with Group B5, the ovary index, number of growing follicle were higher and levels of FSH and LH were lower in Group B2 and B3, expression of ER was higher in Group B1 and B4, IGF-1 and INHalpha was higher in Group B2 and B3, and ACTalpha-beta and FS were lower (all P < 0.05).</p><p><b>CONCLUSION</b>Nirigxin Hongqi Capsule could adjust and balance the local ovarian autocrine and paracrine factors to improve the ovarian function.</p>

Autocrine Extracellular Signal-regulated Kinase Activation in Normal Human Keratinocytes is not Interrupted by Calcium Triggering and is Involved in the Control of Cell Cycle at the Early Stage of Calciuminduced Differentiation

Normal human epidermal keratinocytes (NHEK) respond to the autocrine activated extracellular signal-regulated kinase (ERK) signaling pathway, which contributes to the survival of keratinocytes. However, during the condition of calcium-induced differentiation, how the autocrine ERK signaling is regulated and affected is poorly understood. The purpose of this study was to understand and to obtain clues to the possible function of the autocrine ERK activation during the calcium-induced differentiation of NHEK. We demonstrated that the autocrine activated ERK was not interrupted by calcium triggering and that it was sustained for at least one day after changing the medium. We also found that the autocrine ERK activation was associated with the expression of cyclin D1 and the cell cycle regulation at the early stage of calcium triggering by treating the cells with the mitogen-activated protein kinase inhibitor PD98059. However, the PD98059 treatment did not have a significant influence on the expression of involucrin and loricrin. In addition, we demonstrated that autocrine ERK activation was associated with protein kinase C and p38MAPK signaling. We suggest that the activation of autocrine ERK is not interrupted by calcium triggering and it might participate in cell growth during the early stage of calcium-induced differentiation in NHEK.

ATP released from beta-amyloid-stimulated microglia induces reactive oxygen species production in an autocrine fashion

Present study demonstrated that fibrillar beta-amyloid peptide (fAbeta(1-42)) induced ATP release, which in turn activated NADPH oxidase via the P2X(7) receptor (P2X(7)R). Reactive oxygen species (ROS) production in fAbeta(1-42)-treated microglia appeared to require Ca2+ influx from extracellular sources, because ROS generation was abolished to control levels in the absence of extracellular Ca2+. Considering previous observation of superoxide generation by Ca2+ influx through P2X(7)R in microglia, we hypothesized that ROS production in fAbeta-stimulated microglia might be mediated by ATP released from the microglia. We therefore examined whether fAbeta(1-42)-induced Ca2+ influx was mediated through P2X(7)R activation. In serial experiments, we found that microglial pretreatment with the P2X(7)R antagonists Pyridoxal-phosphate-6-azophenyl-2',4'- disulfonate (100 micrometer) or oxidized ATP (100 micrometer) inhibited fAbeta-induced Ca2+ influx and reduced ROS generation to basal levels. Furthermore, ATP efflux from fAbeta(1-42)-stimulated microglia was observed, and apyrase treatment decreased the generation of ROS. These findings provide conclusive evidence that fAbeta-stimulated ROS generation in microglial cells is regulated by ATP released from the microglia in an autocrine manner.

La prolactina en el sistema inmunológico: aspectos de síntesis y efectos biológicos / Prolactin in the immune system: synthesis and biological effects

Prolactin (PRL) Is a 23 κDa protein hormone that is produced and secreted by the pituitary lactotrophs. Although PRL was initially regarded as an exclusive pituitary hormone, many nonpituitary tissues were later found to contain and produce this hormone. The most established extrapituitary sites that produce PRL are the decidua, the immune system, brain and endometrium. In the immune system, PRL acts as a cytokine where it plays an important role in human immune responses, including in autoimmune diseases. Here, we will discuss the regulation of PRL gene expression in human lymphocytes and review the functions of PRL made by the immune cells, including its involvement in autoimmunity.

La prolactina es una hormona que fue considerada durante mucho tiempo de origen exclusivamente hipofisario, y cuya función más importante era la promoción de la lactancia. Sin embargo, la prolactina no sólo se sintetiza en diversos sitios del organismo, sino que también participa en una amplia variedad de procesos biológicos. Dentro de los sitios de síntesis extrahipofisarios de esta hormona se encuentran diversas células del sistema inmunológico. A este nivel, la prolactina actúa afectando desde la proliferación celular hasta el estado inmune del individuo. En esta revisión presentamos algunos aspectos relativos a la prolactina de origen linfocitario tales como su síntesis, su participación en el sistema inmunológico y su relación con estados de autoinmunidad.

Presence of autocrine hepatocyte growth factor-Met signaling and its role in proliferation and migration of SNU-484 gastric cancer cell line

Autocrine stimulation via coexpression of hepatocyte growth factor (HGF) and its receptor (Met) has been reported in many human sarcomas, but few in carcinomas. In this report, we found that one gastric cancer cell line, SNU-484, among 11 gastric cell lines tested has an autocrine HGF- Met stimulation. RT-PCR, ELISA and scattering assay using MDCK cells revealed that SNU-484 cells secreted a significant amount of active HGF (about 1.25 +/- 0.41 ng/24 h/106 cells) into conditioned medium. Resultantly, Met in this cell line was constitutively phosphorylated. Neutralizing antibodies against HGF reduced the tyrosine phosphorylation of Met, resulting in the inhibition of cell proliferation and migration (P <0.005). To the best of our knowledge, this is the first report on autocrine HGF-Met signaling in a gastric cancer cell line. Our observations with SNU-484 cells suggest that HGF is involved in the development and/or progression of some gastric carcinoma through an autocrine mechanism.

Regulação da síntese e secreção de tireotrofina / Regulation of thyrotropin synthesis and secretion

A secreção de tireotrofina (TSH) é determinada pelo efeito estimulatório do hormônio hipotalâmico estimulador de tireotrofina (TRH) e pela retroalimentação negativa exercida pelos hormônios tireóideos (HT). Superpostos, atuam outros reguladores e aferências do sistema nervoso central. Somatostatina e dopamina inibem a secreção de TSH, já as vias alfa-adrenérgicas centrais são predominantemente estimuladoras e participariam no estímulo da secreção de TSH pelo frio. O estado nutricional modula o eixo através da leptina, por vias diretas e indiretas. O estresse induz redução da secreção de TSH, e discute-se a participação dos glicocorticóides, citocinas e opiáceos. Recentemente, evidenciou-se que fatores locais produzidos na adenohipófise podem atuar de forma autócrina/parácrina, modulando a secreção de TSH. Dentre estes, destacam-se a neuromedina B e o peptídeo liberador de gastrina, que atuam como inibidores locais da secreção de TSH. Discute-se ainda, as alterações do TSH decorrentes da programação neonatal, por hormônios ou desnutrição.

Effects of TGF beta1 autocrine blockage on osteosarcoma cells / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To evaluate the effects of transforming growth factor beta1 (TGFbeta1) autocrine blockage on proliferation activity and drug sensitivity of osteosarcoma. METHODS; Northern blot, MTT determination, and 3H thymidine incorporation were used to investigate the effects of antisense TGF beta1 gene on osteosarcoma.</p><p><b>RESULTS</b>The proliferation of osteosarcoma cells transfected by antisense TGF beta1 gene was suppressed markedly, and adriamycin sensitivity was significantly increased.</p><p><b>CONCLUSION</b>Blockage of osteosarcoma cells TGF beta1 autocrine loop inhibits cell proliferation and enhances chemotherapy sensitivity.</p>

Micropartículas plasmáticas: um novo microambiente de sinalização redox transcelular no sistema vascular / Plasmatic microparticles: a novel redox sinaling microenvironment in the vascular system do autor Marcelo de Almeida Pedro

Micropartículas (MP) são estruturas liberadas por células ativadas ou apoptóticas. Artérias de coelhos lesadas por cateter balão liberam MP fosfatidilserina positivas, com atividade NADPH oxidase produtora de O2 após adição de NADPH, inibida DPI , SOD e MnTBAP. Induziram apoptose de células musculares lisas vasculares. Western blot não revelou proteínas responsáveis pela atividade redox (NADPH oxidase e PDI). MP plasmáticas de pacientes após implante de stent coronário não mostraram atividade NADPH oxidase, mas significativa atividade diaforase 24h pós implante, inibida 40-50 por cento por DPI, SOD e catalase / Microparticles (MP) are released by cells upon activation and apoptosis. Balloon injured rabbit arteries released phosphatidilserine positive MP, with O2 producing NADPH oxidase activity upon NADPH addition, inhibited by DPI, SOD and MnTBAP. MP induced cultured vascular smooth muscle cells apoptosis. Western blot did not show redox active proteins (NADPH oxidase and PDI). Plasmatic MP from coronary stented patients did not have NADPH oxidase activity, but had significant diaphorase activity, inhibited 40-50 per cent by DPI, SOD and catalase...

Secreçäo da insulina: efeito autócrito da insulina e modulaçäo por ácidos graxos / Insulin secretion: insulin autocrinous effect and modulation by fatty acids

A insulina exerce um papel central na regulação da homeostase da glicose e atua de maneira coordenada em eventos celulares que regulam os efeitos metabólicos e de crescimento. A sub-unidade 13 do receptor de insulina possui atividade tirosina quinase intrínseca. A autofosforilação do receptor, induzida pela insulina, resulta na fosforilação de substratos protéicos intracelulares, como o substrato-l do receptor de insulina (IRS-1). O IRS-1 fosforilado associa-se a domínios SH2 e SH3 da enzima PI 3-quinase, transmitindo, desta maneira, o sinal insulínico. A insulina parece exercer feedback positivo na sua secreção, pela interação com seu receptor em células B pancreáticas. Alterações nos mecanismos moleculares da via de sinalização insulínica sugerem uma associação entre resistência à insulina e diminuição da secreção deste hormônio, semelhante ao observado em diabetes mellitus tipo 2. Uma das anormalidades associadas à resistência à insulina é a hiperlipidemia. O aumento do pool de ácidos graxos livres circulantes pode modular a atividade de enzimas e de proteínas que participam na exocitose da insulina. Essa revisão descreve também os possíveis mecanismos de modulação da secreção de insulina pelos ácidos graxos em ilhotas pancreáticas.