Search

Introduction It is now well known that peripheral artery disease, a major health hazard, is primarily associated with impaired blood flow and subsequent ischemia in the hind limb (Hernando and [...], To test if magnitudes of the beneficial actions of C[O.sub.2] water bath therapy on blood flow and vascular density are dependent upon temperature, ischemia in the hind limb of rats was induced by occluding the left femoral artery for 2 weeks and the animals were exposed to water bath therapy with or without C[O.sub.2] at 34 or 41 [degrees]C for 4 weeks (20 min treatment each day for 5 days/week). C[O.sub.2] water bath therapy at 34 [degrees]C increased peak, minimal, and mean blood flow by 190%-600% in the ischemic limb. On the other hand, C[O.sub.2] water bath treatment at 41 [degrees]C increased these parameters of blood flow by 37%, 55%, and 41%, respectively, in the ischemic limb. The small blood vessel count, an index of vascular density, in the ischemic limb was increased by C[O.sub.2] water bath therapy at 34 and 41 [degrees]C by 32% and 122%, respectively. No changes in the ischemic animals by C[O.sub.2] water bath therapy at 34 or 41 [degrees]C were observed in the heart rate, R-R interval, and plasma lipid or glucose levels. These data indicate that the beneficial effect of C[O.sub.2] water bath therapy at 34 [degrees]C on blood flow in the ischemic muscle is greater whereas that on vascular density is smaller than changes in these parameters at 41 [degrees]C. Key words: peripheral ischemia, C[O.sub.2] water bath therapy, blood flow in hind limb, skeletal muscle vascular density, plasma lipids and glucose. En vue d'evaluer si l'importance des bienfaits de l'action du bain therapeutique d'eau au C[O.sub.2] quant a la circulation sanguine et a la densite vasculaire depend de la temperature, nous avons provoque une ischemie dans la patte posterieure de rats par l'occlusion de l'artere femorale gauche pendant 2 semaines et expose les animaux a un bain therapeutique d'eau avec ou sans C[O.sub.2] a 34 ou a 41 [degrees]C sur 4 semaines (exposition sur 20 min une fois par jour, 5 jours/semaine). Le bain therapeutique d'eau au C[O.sub.2] a 34 [degrees]C entrainait une augmentation du flux sanguin maximal, minimal et moyen de 190 % a 600 % dans la patte ischemique. Cependant, le bain therapeutique d'eau au C[O.sub.2] a 41 [degrees]C entrainait une hausse de ces memes parametres du flux sanguin de 37 %, de 55 % et de 41 % respectivement dans la patte ischemique. Le nombre de vaisseaux sanguins de faible calibre, un indice de la densite vasculaire, dans la patte ischemique augmentait avec le bain therapeutique d'eau au C[O.sub.2] a 34 et a 41 [degrees]C de 32 % et de 122 %, respectivement. Chez les animaux porteurs d'une ischemie, nous n'avons observe aucune variation des effets entre les bains therapeutiques d'eau au C[O.sub.2] a 34 [degrees]C ou a 41 [degrees]C sur la frequence cardiaque, l'intervalle R-R, ainsi que sur les lipides plasmatiques ou la glycemie. Ces donnees montrent que les bienfaits du bain therapeutique d'eau au C[O.sub.2] a 34 [degrees]C sont plus importants sur la circulation sanguine dans le muscle ischemique qu'a 41 [degrees]C et moins importants sur la densite vasculaire qu'a 41 [degrees]C. [Traduit par la Redaction] Mots-cles : ischemie peripherique, bain therapeutique d'eau au C[O.sub.2], circulation sanguine dans la patte posterieure, densite vasculaire du muscle squelettique, lipides plasmatiques et glucose.

Introduction Lysophosphatidic acid (LPA), a phospholipid with diverse biological functions, is known to play important roles in wound healing, fetal organ development, tumor cell metastasis, and modulating cardiovascular activities (Abdel-Latif [...], Lysophosphatidic acid (LPA) is an important lipid molecule for signal transduction in cell proliferation. Although the effects of LPA on vascular smooth muscle (VSM) cell growth have been reported previously, the underlying mechanisms of its action are not fully understood. The present study was undertaken to investigate the effects of some inhibitors of different protein kinases and other molecular targets on LPA-induced DNA synthesis as well as gene expression in the aortic VSM cells. The DNA synthesis was studied by the [[sup.3]H]thymidine incorporation method and the gene expression was investigated by the real-time PCR technique. It was observed that the LPA-induced DNA synthesis was attenuated by inhibitors of protein kinase C (PKC) (staurosporine, calphostin C, and bisindolylmaleimide), phosphoinositide 3-kinase (PI3K) (wortmannin and LY294002), and ribosomal p70S6 kinase (p70S6K) (rapamycin). The inhibitors of guanine protein coupled receptors (GPCR) (pertussis toxin), phospholipase C (PLC) (U73122 and D609), and sodium-hydrogen exchanger (NHE) (amiloride and dimethyl amiloride) were also shown to depress the LPA-induced DNA synthesis. Furthermore, gene expressions for PLC [beta]1 isoform, PKC [delta] and [epsilon] isoforms, casein kinase II [beta] isoform, and endothelin-1A receptors were elevated by LPA. These results suggest that the LPA-induced proliferation of VSM cells is mediated through the activation of GPCR and multiple protein kinases as well as gene expressions of some of their specific isoforms. Key words: vascular cell proliferation, lysophosphatidic acid, protein kinases, vascular DNA synthesis, vascular gene expression. L'acide lysophosphatidique (ALP) est une molecule lipidique qui est importante pour la transduction du signal dans la proliferation des cellules. Bien que les effets de l'ALP sur la croissance du muscle lisse vasculaire (MLV) aient ete rapportes anterieurement, les modes d'action sous-jacents n'ont pas encore ete completement eclaircis. Les presents travaux ont ete menes en vue d'etudier les effets de certains inhibiteurs de differentes proteines kinases et autres cibles moleculaires sur la synthese de l'ADN, ainsi que l'expression genique engendrees par l'ALP dans les cellules de MLV aortique. Nous avons etudie la synthese de l'ADN a l'aide de la methode d'incorporation de [[sup.3]H]thymidine, et l'expression genique a l'aide de la technique de PCR en temps reel. Nous avons observe que la synthese d'ADN engendree par l'ALP etait attenuee avec des inhibiteurs de la proteine kinase C (PKC) (staurosporine, calphostine C et bisindolylmaleimide), de la phosphoinositide 3-kinase (PI3K) (wortmannine et LY294002) et de la kinase p70S6 ribosomale (p70S6K) (rapamycine). Nous avons aussi observe que les inhibiteurs des recepteurs de la guanine couples a des proteines (GPCR pour << guanine protein coupled receptors >>) (toxine pertussique), de la phospholipase C (PLC) (U73122 et D609) et de l'echangeur sodium-hydrogene (NHE) (amiloride et dimethyl amiloride) entrainent une inhibition de la synthese d'ADN engendree par l'ALP. En outre, l'expression genique pour l'isoforme PLC [beta]1, les isoformes PKC [delta] et [epsilon], l'isoforme caseine kinase II [beta] et les recepteurs de l'endotheline 1A etait plus elevee avec l'ALP. Ces resultats laissent entendre que l'activation de la GPCR et de multiples proteines kinases, ainsi que de l'expression genique de certaines de leurs isoformes specifiques participerait a la mediation de la proliferation des cellules du MLV engendree l'ALP. [Traduit par la Redaction] Mots-cles : proliferation des cellules vasculaires, acide lysophosphatidique, proteines kinases, synthese d'ADN vasculaire, expression genique vasculaire.

Introduction Peripheral vascular disease is commonly associated with reduction in blood flow and subsequent ischemia in hind limb skeletal muscle (Carmeliet and Jain 2011; Krishna et al. 2015; Dhalla et [...], The effects of C[O.sub.2] water-bath therapy on the hind limb of diabetic animals with or without peripheral ischemia were examined. Diabetes was induced in rats by administering streptozotocin (65 mg x [kg.sup.-1]), and the animals were then divided into 3 groups. After 4 weeks, peripheral ischemia was induced by ligation of the femoral artery for 2 weeks in 2 groups (diabetic ischemic) of diabetic rats, whereas the femoral artery was not occluded in the third group (diabetic). All these animals were subjected to water-bath therapy (with or without C[O.sub.2] mixing; 20 min x [day.sup.-1] for 5 days x [week.sup.-1]) for a period of 4 weeks. Both peak and mean flows, unlike minimal flow, in diabetic ischemic limbs were increased about a twofold by C[O.sub.2] water-bath treatment. Morphological examination of hind limb tissue sections revealed about a twofold increase in the small artery count in diabetic ischemic animals upon C[O.sub.2] water-bath treatment. These results indicate that C[O.sub.2] water-bath therapy augments the blood flow and development of angiogenesis in the skeletal muscle of diabetic ischemic animals and thus may be of some benefit for the treatment of peripheral arterial disease in diabetes. Key words: skeletal muscle angiogenesis, peripheral blood flow, experimental diabetes, peripheral arterial disease, C[O.sub.2] water-bath therapy. Nous avons etudie les effets du traitement en bain d&apos;eau carbogazeuse sur le membre posterieur d&apos;animaux atteints de diabete avec ou sans ischemie peripherique. Nous avons provoque un diabete chez des rats a l&apos;aide de streptozotocine (65 mg x [kg.sup.-1]), et nous avons reparti les animaux dans 3 groupes. Apres 4 semaines, nous avons produit une ischemie peripherique par la ligature de l&apos;artere femorale pendant 2 semaines dans 2 groupes (diabete ischemie) de rats atteints de diabete, alors que l&apos;artere femorale ne subissait pas d&apos;occlusion dans le troisieme groupe (diabete). Nous avons administre un traitement en bain d&apos;eau chez tous ces animaux (avec ou sans melange avec du C[O.sub.2]; 20 min x [jour.sup.-1] pendant 5 jours x [semaine.sup.-1]) pour une periode de 4 semaines. Nous avons observe que, contrairement au flux minimal, les flux maximal et moyen doublaient a peu pres tous 2 dans les membres du groupe diabete ischemie avec bain en eau carbogazeuse. A l&apos;examen morphologique, les coupes de tissu de membre posterieur ont revele que le nombre d&apos;arterioles doublait a peu pres dans le groupe diabete ischemie avec bain en eau carbogazeuse. Ces resultats montrent que le traitement en bain d&apos;eau carbogazeuse permet de faire augmenter le flux sanguin et le developpement de l&apos;angiogenese dans le muscle squelettique d&apos;animaux atteints de diabete avec ischemie, et donc, que ce mode therapeutique pourrait avoir certains avantages dans le traitement de la maladie arterielle peripherique en cas de diabete. [Traduit par la Redaction] Mots-cles : angiogenese dans le muscle squelettique, flux sanguin peripherique, diabete experimental, maladie arterielle peripherique, traitement en bain d&apos;eau carbogazeuse.

Introduction Intracellular free [Ca.sup.2+] concentration ([[[Ca.sup.2+]].sub.i]) plays an important role in the regulation of cardiovascular function, cell growth, and apoptosis under both physiological and pathological conditions (Dhalla et al. 1982; [...], Although plasma levels of lysophosphatidylglycerol (LPG) are increased in hypertension, its role in the pathogenesis of vascular defects is not clear. In view of the importance of [Ca.sup.2+] overload in causing vascular smooth muscle (VSM) dysfunction, the action of LPG on [[[Ca.sup.2+]].sub.i] in cultured A10 VSM cell line was examined by using Fura 2-AM acetoxymethyl ester technique. LPG was found to induce a concentration-dependent increase in [[[Ca.sup.2+]].sub.i] in VSM cells. This change was dependent both on the extracellular and intracellular [Ca.sup.2+] sources, as it was reduced by 30% by EGTA, an extracellular [Ca.sup.2+] chelator, and 70% by thapsigargin, a sarcoplasmic reticulum (SR) [Ca.sup.2+]-pump inhibitor. However the increase in [[[Ca.sup.2+]].sub.i] due to LPG was not altered by caffeine or ryanodine, which affect [Ca.sup.2+]-release through the ryanodine receptors in the SR. On the other hand, LPG-induced change in [[[Ca.sup.2+]].sub.i] was suppressed by 2-nitro-4-carboxyphenyl N,N- diphenylcarbamate, a phospholipase C (PLC) inhibitor, as well as by xestospongin and 2-aminoethoxydiphenyl borate, two inositol trisphosphate (IP3) receptor inhibitors in the SR. These observations support the view that LPG-induced increase in [[[Ca.sup.2+]].sub.i] in VSM cells is mainly a result of [Ca.sup.2+] release from [Ca.sup.2+] pool in the SR through PLC/IP3-sensitive signal transduction mechanism. Furthermore, it is suggested that the elevated level of LPG may induce intracellular [Ca.sup.2+] overload and thus play a critical role in the development of vascular abnormalities. Key words: lysophosphatidylglycerol, vascular smooth muscle cells, intracellular calcium, sarcoplasmic reticulum, vascular abnormalities. Meme si les taux plasmatiques de lysophosphatidylglycerol (LPG) augmentent en cas d&apos;hypertension, son role dans la pathogenese des defectuosites vasculaires demeure a clarifier. Etant donne l&apos;importance de la surcharge en ions [Ca.sup.2+] dans l&apos;apparition d&apos;un dysfonctionnement du muscle lisse vasculaire (MLV), nous avons etudie l&apos;action du LPG sur les concentrations intracellulaires de [Ca.sup.2+] ([[[Ca.sup.2+]].sub.i]) de lignees cellulaires A10 de MLV en culture a l&apos;aide de la technique de Fura 2-AM acetoxymethyl ester. Nous avons observe que le LPG entraine une augmentation--proportionnelle a la concentration--de [[[Ca.sup.2+]].sub.i] dans les cellules de MLV. Cette variation etait dependante des sources extracellulaires comme intracellulaires de [Ca.sup.2+], car celles-ci diminuaient de 30 % avec l&apos;EGTA, un chelateur du [Ca.sup.2+] extracellulaire, et de 70 % avec la thapsigargine, un inhibiteur de la pompe a [Ca.sup.2+] dans le reticulum sarcoplasmique (RS). Cependant, l&apos;augmentation de [[[Ca.sup.2+]].sub.i] qu&apos;entraine le LPG n&apos;etait pas modifiee par la cafeine ni par la ryanodine, lesquelles ont des effets sur la liberation du [Ca.sup.2+] par l&apos;intermediaire des recepteurs de la ryanodine dans le RS. Par contre, les variations de la [[[Ca.sup.2+]].sub.i] qu&apos;entraine le LPG etaient inhibees par le 2-nitro- 4-carboxyphenyl N,N-diphenylcarbamate, un inhibiteur de la phospholipase C (PLC), ainsi que par la xestospongine et le 2 aminoethoxydiphenyl borate, deux inhibiteurs des recepteurs de l&apos;inositol trisphosphate (IP3) dans le RS. Ces observations viennent appuyer la notion selon laquelle l&apos;augmentation de [[[Ca.sup.2+]].sub.i] qu&apos;entraine le LPG dans les cellules du MLV provient principalement de la liberation de [Ca.sup.2+] du<>de [Ca.sup.2+] dans le RS qui suit un mode d&apos;action dependant de la transduction de signaux sensible au systeme PLC/IP3. De plus, il est pressenti que l&apos;augmentation des taux de LPG pourrait entrainer une augmentation de la surcharge en ions [Ca.sup.2+] et, par le fait meme, jouer un role crucial dans la formation d&apos;anomalies vasculaires. [Traduit par la Redaction] Mots-cles: lysophosphatidylglycerol, cellules musculaires lisses vasculaires, calcium intracellulaire, reticulum sarcoplasmique, anomalies vasculaires.

Introduction Peripheral artery disease, a major health hazard worldwide, is normally associated with obstruction of blood supply to the limb mainly as a consequence of atherosclerosis and thrombosis leading to [...], In this study, we investigated the effects of C[O.sub.2] water-bath therapy on blood flow and angiogenesis in the ischemic hind limb, as well as some plasma angiogenic factors in peripheral ischemic model. The hind limb ischemia was induced by occluding the femoral artery for 2 weeks in rats and treated with or without C[O.sub.2] water-bath therapy at 37 [degrees]C for 4 weeks (20 min treatment every day for 5 days per week). The peak blood flow and minimal and mean blood flow in the ischemic skeletal muscle were markedly increased by the C[O.sub.2] water-bath therapy. This increase in blood flow was associated with development of angiogenesis in the muscle, as well as reduction in the ischemia-induced increase in plasma malondialdehyde levels. Although plasma vascular endothelial growth factor and nitric oxide levels were increased in animals with peripheral ischemia, the changes in these biomarkers were not affected by C[O.sub.2] water-bath therapy. These results suggest that augmentation of blood flow in the ischemic hind limb by C[O.sub.2] water-bath therapy may be due to the development of angiogenesis and reduction in oxidative stress. Key words: C[O.sub.2] water-bath therapy, peripheral artery disease, angiogenesis, vascular blood flow, oxidative stress. Dans les presents travaux, nous avons etudie les effets des bains en eau carbogazeuse sur la circulation sanguine et l&apos;angiogenese dans le membre posterieur ischemique, ainsi que certains facteurs angiogeniques dans un modele d&apos;ischemie peripherique. L&apos;ischemie du membre posterieur a ete provoquee par l&apos;occlusion de l&apos;artere femorale pendant 2 semaines chez des rats traites ou non par des bains en eau carbogazeuse a 37 [degrees]C pendant 4 semaines (20 min de traitement quotidien, 5 jours par semaine). Les bains en eau carbogazeuse permettaient d&apos;augmenter de facon marquee le flux sanguin maximal et le flux sanguin minimal ainsi que le flux sanguin moyen dans le muscle squelettique ischemique. Cette augmentation de la circulation sanguine etait associee a la formation d&apos;une angiogenese dans le muscle ainsi qu&apos;a une reduction de l&apos;augmentation des taux plasmatiques de malondialdehyde provoquee par l&apos;ischemie. Meme si les taux plasmatiques de VEGF (pour<>) et d&apos;oxyde nitrique augmentaient chez les animaux presentant une ischemie peripherique, les variations de taux de ces biomarqueurs n&apos;etaient pas affectees par les bains en eau carbogazeuse. Ces resultats laissent entendre que l&apos;augmentation de la circulation sanguine dans le membre posterieur ischemique par les bains en eau carbogazeuse pourrait etre causee par la formation d&apos;une angiogenese et la reduction du stress oxydatif. [Traduit par la Redaction] Mots-cles: bains en eau carbogazeuse, insuffisance arterielle peripherique, angiogenese, flux sanguin vasculaire, stress oxydatif.

Previously, it was shown that both blood flow and angiogenesis in the ischemic hind limb of diabetic rats were increased upon CO2 treatment for 4 weeks. In the present study, we have compared the effects of 6 weeks CO2 therapy in diabetic rats with or without peripheral ischemia. Diabetes was induced in rats by a tail vein injection of streptozotocin (65 mg/kg body weight), whereas peripheral ischemia was produced by occluding the femoral artery at 2 weeks of inducing diabetes. Both diabetic and diabetic-ischemic animals were treated with or without CO2 water-bath at 37 °C for 6 weeks (30 min/day; 5 days/week) starting at 2 weeks, after the induction of ischemia. CO2 treatment did not affect heart rate and R-R interval as well as plasma levels of creatine kinase, glucose, cholesterol, triglycerides and high density lipoproteins. Unlike the levels of plasma Ox-LDL, MDA and TNF-α, the levels of NO in diabetic group were increased by CO2 water-bath treatment. On the other hand, the levels of plasma Ox-LDL and MDA were decreased whereas that of NO was increased without any changes in TNF-α level in diabetic-ischemic animals upon CO2 therapy. Treatment of diabetic animals with CO2 increased peak, mean and minimal blood flow by 20, 49 and 43% whereas these values were increased by 53, 26 and 80% in the diabetic-ischemic group by CO2 therapy, respectively. Blood vessel count in diabetic and diabetic-ischemic skeletal muscles was increased by 73 and 136% by CO2 therapy, respectively. These data indicate that peripheral ischemia augmented the increase in blood flow and development of angiogenesis in diabetic skeletal muscle upon CO2 therapy. It is suggested that greater beneficial effects of CO2 therapy in diabetic-ischemic animals in comparison to diabetic group may be a consequence of difference of changes in the redox-sensitive signal transduction mechanisms. [ABSTRACT FROM AUTHOR]