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We have found that eIF3a plays an important role in bleomycin-induced pulmonary fibrosis, and up-regulation of eIF3a induced by TGF-β1 is mediated via the ERK1/2 pathway. Whether ERK1/2--eIF3a signal pathway is involved in calcitonin gene-related peptide (CGRP)-mediated pathogenesis of bleomycin-induced pulmonary fibrosis remains unknown. Pulmonary fibrosis was induced by intratracheal instillation of bleomycin (5 mg/kg) in rats. Primary pulmonary fibroblasts were cultured to investigate the proliferation by BrdU incorporation method and flow cytometry. Sensory CGRP depletion by capsaicin exacerbated bleomycin-induced pulmonary fibrosis in rats, as shown by a significant disturbed alveolar structure, marked thickening of the interalveolar septa and dense interstitial infiltration by inflammatory cells and fibroblasts, accompanied with increased expression of TGF- β1, eIF3a, phosphorylated ERK1/2, α-SMA collagen I, and collagen III. Exogenous application of CGRP significantly inhibited TGF-β1- induced proliferation and differentiation of pulmonary fibroblasts concomitantly with decreased expression of eIF3a, phosphorylated ERK1/2, α-SMA, collagen I, and collagen III. These effects of CGRP were abolished in the presence of [CGRP.sub.8-37]. These results suggest that endogenous CGRP is related to the development of pulmonary fibrosis induced by bleomycin, and the inhibitory effect of CGRP on proliferation of lung fibroblasts involves the ERK1/2--eIF3a signaling pathway. Key words: calcitonin gene-related peptide, pulmonary fibrosis, pulmonary fibroblasts, eukaryotic translation initiation factor 3a, TGF-β1. Nous avons observe que l'eIF3a (sous-unite A du facteur de demarrage de la traduction eucaryote) joue un role important dans la fibrose pulmonaire induite par la bleomycine et que la regulation a la hausse de l'eIF3a induite par le facteur TGF-β1 est mediee par la voie de signalisation des proteines kinases ERK1/2. On ne sait toujours pas si la voie de signalisation ERK1/2-- eIF3a joue un role dans la pathogenese de la fibrose pulmonaire induite par la bleomycine et mediee par le CGRP (peptide lie au gene de la calcitonine). Nous avons induit une fibrose pulmonaire en instillant de la bleomycine (a 5 mg/kg) par voie intratracheale chez des rats. Nous avons cultive les fibroblastes pulmonaires primaires en vue d'etudier leur proliferation a l'aide de la methode d'incorporation de BrdU et de la cytometrie en flux. La deficience de CGRP sensoriel par la capsaicine a amplifie le phenomene de fibrose pulmonaire induite par la bleomycine chez le rat: nous avons observe une perturbation importante de la structure alveolaire, une augmentation marquee de l'epaisseur des septa interalveolaires et une infiltration dense de cellules inflammatoires et de fibroblastes dans le tissu interstitiel, accompagnees d'une augmentation de l'expression du facteur TGF-β1, de l'eIF3a, des ERK1/2 phosphorylees, de la SMA-α (actine du muscle lisse alpha) ainsi que du collagene I et du collagene III. L'application exogene de CGRP a entraine une nette inhibition de la proliferation induite par le TGF-β1 et de la differentiation des fibroblastes pulmonaires en tandem avec une diminution de l'expression de l'eIF3a, des ERK1/2 phosphorylees, de la SMA-α ainsi que du collagene I et du collagene III. Ces effets du CGRP etaient supprimes en presence de [CGRP.sub.8-37]. Ces resultats laissent entendre que le CGRP endogene serait lie a la formation de la fibrose pulmonaire induite par la bleomycine et que la voie de signalisation ERK1/2--eIF3a jouerait un role dans l'effet inhibiteur du CGRP sur la proliferation des fibroblastes pulmonaires. [Traduit par la Redaction] Mots-cles: peptide lie au gene de la calcitonine, fibrose pulmonaire, fibroblastes pulmonaires, facteur 3a de demarrage de la traduction eucaryote, TGF-β1., Introduction Pulmonary fibrosis (PF) is characterized by fibroblast proliferation and extracellular matrix (ECM) remodeling, which result in irreversible distortion of the lung architecture (Selman et al. 2001; Cook et al. [...]

Fluorofenidone (AKF-PD) is a novel pyridone derivate that targets transforming growth factor-β (TGF-[β.sup.1]) signaling. Previous studies have proven that AKF-PD functions as an antifibrotic agent in pulmonary fibrosis and renal fibrosis models. Activated TGF-[β.sub.1] signaling is thought to be a major feature of pulmonary hypertension (PH). TGF-[β.sub.1] exerts powerful proproliferation effects on pulmonary arterial smooth muscle cells (PASMCs), and hence, prompts vascular remodeling. This study is designed to investigate the effect of AKF-PD on vascular remodeling in a rat model of hypoxia-induced PH. PH was induced in rats by 4 weeks of hypoxia. The expression of TGF-[β.sub.1], collagen I, and collagen III was analyzed by ELISA, immunohistochemistry, real-time PCR, or Western blot. Proliferation of cultured PASMCs was determined by the BrdU incorporation method and flow cytometry. The results showed that AKF-PD treatment (0.5 or 1.0 g x (kg body masse x [d.sup.-1]) for 4 weeks attenuated pulmonary vascular remodeling and improved homodynamic parameters. TGF-[β.sub.1] level was significantly down-regulated by AKF-PD both in vivo and in vitro. Furthermore, hypoxia- and TGF-[β.sub.1]-induced PASMC proliferation and collagen expression were both significantly suppressed by AKF-PD. These results suggest that AKF-PD ameliorates the progression of PH induced by hypoxia in rats through its regulation of TGF-[β.sub.1] expression, PASMC proliferation, and the extracellular matrix. Key words: fluorofenidone, pulmonary hypertension, pulmonary artery smooth muscle cells, transforming growth factor- [β.sub.1], collagen. La fluorofenidone (AKF-PD) est un nouveau derive de la pyridone qui cible la signalisation du facteur TGF-[β.sub.1]. Des etudes anterieures ont prouve que le AKF-PD agit comme agent anti-fibrogene dans des modeles de fibroses pulmonaire et renale. L'activation de la signalisation du TGF-[β.sub.1] constitue l'une des caracteristiques principales de l'hypertension pulmonaire (HP). Le TGF-[β.sub.1] exerce un puissant effet pro-proliferatif sur les cellules musculaires lisses de l'artere pulmonaire (CMLAP), favorisant alors le remodelage vasculaire. L'etude presente a ete concue afin d'examiner les effets du AKF-PD sur le remodelage vasculaire dans un modele d'HP induite par l'hypoxie. L'HP a ete induite par une hypoxie de 4 semaine chez des rats, et l'expression du TGF-[β.sub.1], du collagene I et du collagene III a ete analysee par ELISA, immunohistochimie, PCR en temps reel ou buvardage Western. La proliferation des CMLAP en culture a ete determinee par incorporation du BrdU et par cytometrie en flux. Les resultats ont montre que le traitement au AKF-PD (0,5 ou 1,0 g x (kg de masse corporelle) x [d.sup.-1]) pendant 4 semaines attenuait le remodelage vasculaire pulmonaire et ameliorait les parametres hemodynamiques. Le niveau de TGF-[β.sub.1] etait significativement regule a la baisse par le AKF-PD in vivo et in vitro. De plus, la proliferation des CMLAP induite par l'hypoxie et le TGF-[β.sub.1] ainsi que l'expression du collagene etaient toutes deux significativement diminuees par le AKF-PD. Ces resultats suggerent que le AKF-PD ameliore la condition des rats atteints d'HP induite par l'hypoxie au moyen de la regulation de l'expression du TGF-[β.sub.1], de la proliferation des CMLAP et de la matrice extracellulaire. [Traduit par la Redaction] Mots-cles: fluorofenidone, hypertension pulmonaire, cellules musculaires lisses de l'artere pulmonaire, facteur TGF-[β.sub.1], collagene., Introduction Pulmonary hypertension (PH) is a serious syndrome in which obstructed, constricted, small pulmonary arteries, and increased pulmonary vascular resistance can ultimately lead to right-ventricular hypertrophy and failure. Although the [...]

Hyperglycemia impairs the function of endothelial cells. Sirtuin 1 (SIRT1) is involved in regulating the function of endothelial cells. Resveratrol, a polyphenol found in many plant species, exerts protective effects on endothelial cells through activation of SIRT1. The aims of this work were to explore whether BTM- 0512, a novel derivative of resveratrol, is able to exert beneficial effects on high glucose-induced dysfunction of endothelial cells through regulation of SIRT1. We found that high glucose significantly impaired the function of endothelial cells as shown by reduced tube formation, cell migration, and cell adhesion concomitantly with downregulation of mRNA expression of SIRT1 and vascular endothelial growth factor as well as increased tumor necrosis factor-α release and reactive oxygen species production. These effects of high glucose were inhibited by pretreatment with BTM-0512. The beneficial effects of BTM-0512 on high glucose-induced cell dysfunction were abolished by splitomicin, a specific inhibitor of SIRT1. The regulatory effects of BTM-0512 on high glucose-induced changes in vascular endothelial growth factor mRNA expression and tumor necrosis factor-α release were also abolished by splitomicin. The results suggest that BTM-0512 exerts beneficial effects on high glucose-induced endothelial cell dysfunction through regulation of the SIRT1 - reactive oxygen species - vascular endothelial growth factor - tumor necrosis factor-α pathway. Key words: sirtuin 1, resveratrol derivative, endothelial cell, high glucose. L'hyperglycemie nuit a la fonction des cellules endotheliales. La sirtuine 1 (SIRT1) participe a la regulation de la fonction des cellules endotheliales. D'apres des etudes, le resveratrol qui est un polyphenol present dans de nombreuses especes de plantes exerce un effet prophylactique sur les cellules endotheliales par l'activation de la SIRT1. Cette etude se propose de verifier si un nouveau derive du resveratrol, le BTM-0512, a un effet benefique sur la dysfonction des cellules endotheliales suscitee par une forte dose de glucose via la regulation de la SIRT1. D'apres nos observations, une forte dose de glucose nuit significativement a la fonction des cellules endotheliales comme le revele la diminution de la formation, de la migration et de l'adherence des tubes combinee a la regulation a la baisse de l'expression de l'ARNm de la SIRT1, du facteur de croissance de l'endothelium vasculaire et l'augmentation de la liberation du facteur de necrose tumorale α et de la production des especes reactives de l'oxygene. Les effets attribues a la forte dose de glucose sont annules par l'administration prealable de BTM-0512. Les effets benefiques de BTM-0512 sur la dysfonction des cellules endotheliales suscitee par une forte dose de glucose sont abolis par la splitomicine, un inhibiteur specifique de la SIRT1. Les effets regulateurs de BTM-0512 sur les modifications suscitees par la forte dose de glucose (expression de l'ARNm du facteur de croissance de l'endothelium vasculaire, liberation du facteur de necrose tumorale α) sont aussi abolis par la splitomicine. D'apres ces observations, le BTM-0512 a des effets benefiques sur la dysfonction des cellules endotheliales suscitee par une forte dose de glucose par son action sur la voie suivante : SIRT1 - especes reactives de l'oxygene - facteur de croissance de l'endothelium vasculaire - facteur de necrose tumorale α. Mots-cles : sirtuine 1, derive du resveratrol, cellules endotheliales, concentration elevee de glucose. [Traduit par la Redaction], Introduction Hyperglycemia is a characteristic feature of diabetes mellitus, and hyperglycemia-induced endothelial dysfunction is the primary cause of vascular complications in diabetes. Endothelial dysfunction comprises a number of functional alterations, [...]

It is proposed that myocardial cell apoptosis causes ventricular remodeling and heart failure. The aim of the present study was to determine the effects of rutaecarpine (Rut) on hypoxia-reoxygenation (H-R)-induced apoptosis in myocardial cell line H9c2, as well as the underlying mechanisms. Cultured H9c2 cells were exposed to hypoxia for 24 h, followed by 12 h reoxygenation. Rut (in concentrations of 0.1, 1, and 10 µmol/L) was added 1 h prior to H-R. Cell viability and lactate dehydrogenase were measured to evaluate the cell injuries. Apoptosis was evaluated by Hoechst 33258 staining and flow cytometry. NADPH oxidase activity was measured by assay kit; intracellular reactive oxygen species (ROS) generation was detected by 2',7'-dichlorofluorescein diacetate; and Nox2, Nox4, and [p47.sup.phox] mRNA and protein expression were analyzed by real-time PCR and Western blotting, respectively. The results showed that H-R significantly decreased cell viability and increased the lactate dehydrogenase release, as well as the apoptotic rate, concomitantly with enhanced NADPH oxidase activity. H-R also upregulated mRNA and protein expressions of Nox2, Nox4, and [p47.sup.phox] and increased ROS production. Treatment with Rut markedly reversed these effects introduced by H-R. These results suggest that the protective effects of Rut against H-R-induced myocardial cell injury and apoptosis might, at least partly, be due to the inhibition of the NADPH oxidase--ROS pathway. Key words: myocardial cell, hypoxia-reoxygenation, rutaecarpine, NADPH oxidase, apoptosis. On considere que l'apoptose des cellules myocardiques est a l'origine du remodelage ventriculaire et de l'insuffisance cardiaque. La presente etude a eu pour but de determiner les effets de la rutoecarpine (Rut) sur l'apoptose induite par hypoxie-reoxygenation (H-R) dans la lignee de cellules myocardiques H9c2, ainsi que les mecanismes sous-jacents. On a expose les cellules H9c2 cultivees a une hypoxie pendant 24 h, puis a une reoxygenation pendant 12 h. On a ajoute; la Rut (0,1, 1 et 10 µmol/L) 1 h avant l'exposition a l'H-R. On a mesure; la viabilite; cellulaire et la lactase dehydrogenase pour eevaluer les lesions cellulaires. On a evaluee l'apoptose apres coloration avec Hoechst 33258 et par cytomeetrie en flux. On a mesure; l'activite; de la NADPH oxydase par un coffret de dosage, de;tecte; la production intracellulaire de formes reactives de l'oxygeene au moyen du 2',7'-dichlorofluoresceine diaceetate, et analyse l'expression de la proteine et de l'ARNm de Nox2, Nox4 et [p47.sup.phox] par PCR en temps re;el et transfert Western, respectivement. Les re;sultats ont montre; que l'H-R a significativement diminue; la viabilite; cellulaire et augmente; la libe;ration de lactase de;shydroge;nase ainsi que l'apoptose, en plus de stimuler l'activite; de la NADPH oxydase, de reguler positivement la proteine de l'ARNm de Nox2, Nox4 et [p47.sup.phox], et d'augmenter la production de formes reactives de l'oxygeene. Le traitement au Rut a renverse de facon marquee les effets produits par l'H-R. Ces resultats donnent a penser que les effets protecteurs de Rut contre la leesion et l'apoptose des cellules myocardiques induites par H-R pourraient, du moins en partie, (etre attribuables a l'inhibition de la voie NADPH oxydase--FRO. Mots-cles: cellule myocardique, hypoxie-reoxygeenation, rutoecarpine, NADPH oxydase, apoptose. [Traduit par la Redaction], Introduction Ischemia-reperfusion injury is a common cause of mortality due to myocardial ischemia, circulatory shock, stroke, and organ transplantation (Becker et al. 2000; Lefer and Lefer 1993; Ratych and Bulkley [...]

This study was designed to explore the role of asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthesis, in platelet aggregation in hypertension and its possible mechanisms. Spontaneously hypertensive rats (SHR) and L-NAME-induced hypertensive rats were orally administered with L-arginine (1 g/(kg-day) for 14 days. Systolic blood pressure, platelet aggregation, and plasma tissue factor (TF) level and activity were measured. The plasma concentration of ADMA in SHR was determined. In vitro, platelet-rich plasma isolated from Wistar rats was prepared in order to observe the effect of exogenous ADMA on platelet aggregation and TF level and (or) activity in platelet-rich plasma. In both types of hypertensive rats, systolic blood pressure, platelet aggregation, and the level and activity of plasma TF were elevated compared with corresponding control animals. Plasma ADMA level was also increased in SHR. Treatment with L-arginine, a competitor of ADMA, lowered blood pressure and inhibited platelet aggregation concomitantly with a decrease in plasma TF level and activity in both types of hypertensive rats. We also found that exogenous ADMA promoted platelet aggregation and increased TF level and (or) activity in platelet-rich plasma, an effect that was inhibited by pretreatment with L-arginine. Importantly, the enhanced platelet aggregation induced by exogenous ADMA was reduced by pretreatment with anti-TF antibody. The results suggest that endogenous ADMA may be involved in platelet hyperaggregation status in hypertension, and the facilitation of platelet aggregation by ADMA is related to upregulation of the level and activity of plasma TF. Key words: asymmetric dimethylarginine, L-arginine, hypertensive rats, platelet aggregation, tissue factor. La presente etude a eu pour objectif d'examiner le role de la dimethylarginine asymetrique (ADMA), un inhibiteur endogene de la synthese du monoxyde d'azote, dans l'agregation plaquettaire lors d'hypertension et ses possibles meecanismes. On a administre; de la L-arginine (1 g/(kgjour)) par voie orale, pendant 14 jours a des rats spontanement hypertendus (RSH) et a des rats rendus hypertensifs par L-NAME. On a mesure la pression arterielle systolique, l'agregation plaquettaire, de mieme que le taux et l'activite du facteur tissulaire (FT) plasmatique. On a determine la concentration plasmatique d'ADMA chez les RSH. On a prepare in vitro du plasma riche en plaquettes, isole de rats Wistar, pour observer l'effet de l'ADMA exogeme sur l'agregation plaquettaire et le taux et (ou) l'activite; du FT dans le plasma. Chez les deux types de rats hypertendus, la pression arterielle systolique, l'agregation plaquettaire ainsi que le taux et l'activite; du FT plasmatique ont augmente; comparativement a ceux des animaux temoins. Le taux d'ADMA plasmatique a aussi augmente; chez les RSH. Le traitement a la L-arginine, un compeetiteur d'ADMA, a abaisse la pression arterielle, et inhibe l'agregation plaquettaire tout en diminuant le taux et l'activite du FT chez les deux types de rats. L'ADMA exogene a favorise; l' agre;gation plaquettaire et augmente; le taux et (ou) l'activite; du FT dans le plasma riche en plaquettes, un effet qui a ete inhibee par un pretraitement a la L-arginine. Fait important, l'augmentation de l'agregation plaquettaire induite par l'ADMA endogeene a ete reduite par un pretraitement avec un anticorps anti-FT. Les resultats suggerent que l'ADMA endogeene pourrait (etre impliqueee dans l'eetat d'hyperagreegation plaquettaire lors d'hypertension, et la facilitation de l'agregation plaquettaire par l'ADMA est associeeea la regulation positive du taux et de l'activite du FT. Mots-cles: dimethylarginine asymetrique, L-arginine, rats hypertendus, agregation plaquettaire, facteur tissulaire. [Traduit par la Redaction], Introduction Hypertension has many risks and complications, especially cardiovascular ones (Bonderman et al. 2007; Rodriguez-Porcel et al. 2003). It has been shown that the major complications, such as coronary heart [...]

Dysfunction of capsaicin-sensitive sensory nerves is involved in cardiac remodeling, and rutaecarpine has been shown to exert a beneficial effect on cardiac function through activating the sensory nerves. This study was conducted to explore the potential inhibitory effect of rutaecarpine on cardiac remodeling and the underlying mechanisms. A rat cardiac remodeling model was established by injection of isoprenaline (5 mg/kg per day, s.c.) for 10 days. Rutaecarpine (10 or 40 mg/kg, i.g.) was coadministrated with isoprenaline to evaluate the effect of rutaecarpine on cardiac remodeling. After echocardiographic analysis was performed, blood samples were collected to quantify calcitonin gene-related peptide (CGRP), dorsal root ganglia were isolated for examining CGRP mRNA expression, and the hearts were weighed and saved for evaluating the parameters related to apoptosis and hypertrophy. Isoprenaline significantly increased the ratio of left ventricle weight to body weight, the cross-sectional area of cardiomyocytes, cardiac apoptosis, and collagen deposition concomitantly with decreased CGRP production, which were reversed by rutaecarpine treatment. The beneficial effects of rutaecarpine were attenuated by pretreatment with capsaicin, which selectively depleted CGRP. These results suggest that rutaecarpine was able to reverse isoprenaline-induced cardiac remodeling through stimulating CGRP production. Key words: rutaecarpine, calcitonin gene-related peptide, cardiac remodeling, isoprenaline. Le dysfonctionnement des nerfs sensitifs sensibles a la capsalcine est implique dans le remodelage cardiaque. Par ailleurs, des travaux ont montre que la rutEecarpine a des effets beenefiques sur la fonction cardiaque en activant les nerfs sensitifs. La presente etude a eu pour but d'examiner l'effet inhibiteur potentiel de la rutaecarpine sur le remodelage cardiaque et les mecanismes sous-jacents. On a realise; un modele de remodelage cardiaque chez le rat injection d'isoprenaline (5 mg/kg s.c. par jour.) pendant 10 jours. On a coadministre la rutEecarpine (10 ou 40 mg/kg i.g.) et l'isoprenaline pour evaluer l'effet de la rutEecarpine sur le remodelage. Apres une analyse echocardiographique, on a preleve des echantillons de sang pour quantifier le peptide relie au gene de la calcitonine (CGRP), isole les ganglions des racines dorsales pour examiner l'expression de l'ARNm du CGRP, pese et conserve; les coeurs pour evaluer les parametres associeesa l'apoptose et a l'hypertrophie. L'isoprenaline a augmente de manieere significative le rapport ventricule gauche/poids corporel, l'aire de section des cardiomyocytes, l'apoptose cardiaque et le depot de collage;ne, et diminuee la production de CGRP; le traitement a la rutaecarpine a renverse ces effets. Les effets benefiques de la rutaecarpine ont eete; attends par un preetraitement a la capsalcine, qui a appauvri selectivement les CGRP. Ces reesultats donnent a penser que la rutaecarpine a pu renverser le remodelage cardiaque induit par l'isoprenaline en stimulant la production de CGRP. Mots-cles: rutEecarpine, peptide relie au gene de la calcitonine, remodelage cardiaque, isoprenaline. [Traduit par la Redaction], Introduction Cardiac remodeling is a pathological condition that ultimately progresses into heart failure if not treated properly (Lips et al. 2003). It is characterized by cardiac hypertrophy, apoptosis, and accumulation [...]

Transforming growth factor (TGF)-[[beta].sub.1] is one of the most pleiotropic and multifunctional peptides known. While the cardioprotective effect of TGF-[[beta].sub.1] during ischemia is well known, the specific role of TGF-[[beta].sub.1] in altering the cardiac remodeling process remains unclear. This study was designed to examine the regulation of hypoxia-reoxygenation-mediated collagen type I expression and activity of matrix metalloproteinases (MMPs) by overexpression of TGF-[[beta].sub.1] in cultured HL-1 mouse cardiomyocytes. TGF-[[beta].sub.1] was overexpressed in cardiomyocytes by transfection with adeno-associated virus (AAV)/TGF-[[beta].sup.Latent.sub.1] or with AAV/TGF-[[beta].sup.ACT.sub.1] (active TGF-[[beta].sub.1]). Twenty-four hours of hypoxia followed by 3 h of reoxygenation (H-R) markedly enhanced (pro)collagen type I expression and activity of MMPs concomitant with an increase in reactive oxygen species (ROS) release and LOX-I expression. Over-expression of TGF-[[beta].sub.1] reduced these alterations induced by H-R. TGF-[[beta].sub.1] overexpression also blocked H-R-mediated p38 and p44/42 MAPK activation. Transfection with AAV/TGF-[[beta].sup.ACT.sub.1] was superior to that with AAV/TGF-[[beta].sup.Latent.sub.1]. These data for the first time demonstrate that H-R induces signals for cardiac remodeling in cardiomyocytes and TGF-[[beta].sub.1] can modulate, possibly via antioxidant mechanism, these signals. These findings contribute to further understanding of the role of TGF-[[beta].sub.1] in the cardiac remodeling process. transforming growth factor-[[beta].sub.1]; HL-1 adult murine cardiomyocytes; metalloproteinases

Abstract: Asymmetric dimethylarginine (ADMA), the endogenous nitric oxide synthase inhibitor, is thought to be a key factor contributing to endothelial dysfunction. Tea catechins can cause an endothelium-dependent vasorelaxation. The present [...]