Short-term insulin treatment and aortic expressions of IGF-1 receptor and VEGF mRNA in diabetic rats

2002 ◽  
Vol 283 (5) ◽  
pp. H1761-H1768 ◽  
Author(s):  
Tsuneo Kobayashi ◽  
Katsuo Kamata

We investigated the relationship between the changes in vascular responsiveness and growth factor mRNA expressions induced by 1-wk treatment with high-dose insulin in control and established streptozotocin (STZ)-induced diabetes. Aortas from diabetic rats, but not those from insulin-treated diabetic rats, showed impaired endothelium-dependent relaxation in response to ACh (vs. untreated controls). The ACh-induced nitrite plus nitrate (NOx) level showed no significant difference between controls and diabetics. Insulin treatment increased NOx only in diabetics. In diabetics, insulin treatment significantly increased the aortic expressions of endothelial nitric oxide synthase (eNOS) mRNA and VEGF mRNA. The expression of IGF-1 mRNA was unaffected by diabetes or by insulin treatment. In contrast, the mRNA for the aortic IGF-1 receptor was increased in diabetics and further increased in insulin-treated diabetics. In aortic strips from age-matched control rats, IGF-1 caused a concentration-dependent relaxation. This relaxation was significantly stronger in strips from STZ-induced diabetic rats. These results suggest that in STZ-diabetic rats, short-term insulin treatment can ameliorate endothelial dysfunction by inducing overexpression of eNOS and/or VEGF mRNAs possibly via IGF-1 receptors. These receptors were increased in diabetes, perhaps as result of insulin deficiency.

Nitric Oxide ◽  
2001 ◽  
Vol 5 (3) ◽  
pp. 252-260 ◽  
Author(s):  
Seiichi Oyadomari ◽  
Tomomi Gotoh ◽  
Kazumasa Aoyagi ◽  
Eiichi Araki ◽  
Motoaki Shichiri ◽  
...  

Stroke ◽  
2013 ◽  
Vol 44 (suppl_1) ◽  
Author(s):  
Xu Cui ◽  
Michael Chopp ◽  
Tao Yan ◽  
Ruizhuo Ning ◽  
Cynthia Roberts ◽  
...  

Background: Stroke induced white matter damage is associated with neurological functional deficits, but the underlying mechanisms are not well understood. Endothelial nitric oxide synthase knockout (eNOS-/-) mice exhibited a higher mortality, more severe neurological functional deficit, and decreased neurogenesis, angiogenesis and arteriogenesis after stroke than wild type mice. There are no reports as to whether eNOS is related to the white matter change post-stroke. Methods: Adult male C57BL/6 WT and eNOS -/- mice were subjected to permanent middle cerebral artery occlusion (MCAo) by a filament and sacrificed 7 days after MCAo. Functional evaluation, infarct volume measurement, and immunostaining for analysis of white matter changes were performed. Results: There is no significant difference in the infarction volume between wild type and eNOS -/- (wild type : 23.09%±3.32%; eNOS-/-: 27.83%±4.92%, p=0.436, n=9/group). However, eNOS -/- mice showed significantly decreased functional outcome tested by the singal pellet reaching test (wild type: 38.46%%±1.43%, eNOS-/-: 27.45%±2.41%, p=0.0017). eNOS -/- mice also exhibited increased white matter damage compared to wild type mice, including decrease: 1. Axonal density stained by Bielshowsky Silver in the ipsilateral striatal bundles (wild type: 22.06%±3.0%, eNOS-/-: 13.32%±2.18%,, p=0.031), and in the contralateral striatal bundles (wild type: 65.35%±3.97%, eNOS-/-: 29.38%±5.84%, p=0.02); 2. Density of phasphorylated neurofilament by SMI31-immunoflureoscent staining (wild type: 24.11%±2.06%, eNOS-/-: 7.90%±1.70%, p=0.009); 3. The number of CNPase-positive oligodendrocytes in the ischemic border (wild type: 52.23±5.10, eNOS-/-: 35.59±5.33, p=0.041); 4. The number of NG2-positive oligodendrocyte progenitors in the ischemic border (wild type: 26.22±2.31, eNOS-/-: 18.38±1.95, p=0.0187). There is no significant difference in the density of Luxol fast blue stained myelin in the ipsilateral striatal bundles between wild type and eNOS -/- mice (wild type: 25.21%±3.64%; eNOS-/-: 21.39%±6.29%, p=0.260). Conclusions: We are the first to report that eNOS not only regulates vascular changes and neurogenesis, but also plays an important role in white matter changes after stroke.


1997 ◽  
Vol 17 (10) ◽  
pp. 5719-5726 ◽  
Author(s):  
J Alonso ◽  
L Sánchez de Miguel ◽  
M Montón ◽  
S Casado ◽  
A López-Farré

Changes in endothelial nitric oxide synthase (eNOS) expression may be involved in the endothelium-dependent vasorelaxation dysfunction associated with several vascular diseases. In the present work, we demonstrate that eNOS mRNA contains a previously undescribed cis element in the 3' untranslated region (3' UTR). A U+C-rich segment in the 3' UTR is critical in complex formation with bovine aortic endothelial cell cytosolic proteins. Tumor necrosis factor alpha (TNF-alpha), which destabilizes eNOS mRNA, increased the binding activity of the cytosolic proteins in a time-dependent manner. These data suggest that endothelial cytosolic proteins bind to the 3' UTR of eNOS mRNA. These proteins may play a role in TNF-alpha-induced eNOS mRNA destabilization.


Molecules ◽  
2019 ◽  
Vol 24 (7) ◽  
pp. 1259 ◽  
Author(s):  
Kayo Horie ◽  
Naoki Nanashima ◽  
Hayato Maeda

Phytoestrogens are plant-derived chemicals that are found in many foods and have estrogenic activity. We previously showed that blackcurrant extract (BCE) and anthocyanins have phytoestrogenic activity mediated via estrogen receptors (ERs), and anthocyanins may improve vascular function. BCE contains high levels of anthocyanins, but their health-promoting effects are unclear. This study examined the effects of BCE on the regulation of endothelial nitric oxide synthase (eNOS) expression and nitric oxide (NO) synthesis in human endothelial cells as key regulators in cardiovascular disease. The results showed that eNOS mRNA levels were significantly upregulated in BCE- or anthocyanin-treated human vascular endothelial cells but decreased in cells treated with fulvestrant, an ER antagonist. These results corresponded with NO levels, suggesting that BCE and anthocyanin may regulate NO synthesis via eNOS expression. Thus, the phytoestrogenic effects exerted by BCE via ERs influenced eNOS mRNA expression and NO synthesis. In vivo, we investigated whether anthocyanin-rich BCE upregulated eNOS protein expression in ovariectomized (OVX) rats, a widely used animal model of menopause. Our results showed that anthocyanin-rich BCE significantly upregulated eNOS mRNA levels and NO synthesis through phytoestrogenic activity and therefore promoted blood vessel health in OVX rats as a postmenopausal model.


2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Yuehong Wang ◽  
Zizhuo Li ◽  
Yu Zhang ◽  
Wei Yang ◽  
Jiantao Sun ◽  
...  

Long-term heavy alcohol consumption is considered to be one of the main causes of left ventricular dysfunction in alcoholic cardiomyopathy (ACM). As previously suggested, high-dose alcohol induces oxidation stress and apoptosis of cardiomyocytes. However, the underlying mechanisms are yet to be elucidated. In this study, we found that high-dose alcohol treatment stimulated expression and activity of Pin1 in mouse primary cardiomyocytes. While siRNA-mediated knockdown of Pin1 suppressed alcohol-induced mouse cardiomyocyte apoptosis, overexpression of Pin1 further upregulated the numbers of apoptotic mouse cardiomyocytes. We further demonstrated that Pin1 promotes mitochondria oxidative stress and loss of mitochondrial membrane potential but suppresses endothelial nitric oxide synthase (eNOS) expression in the presence of alcohol. Taken together, our results revealed a pivotal role of Pin1 in regulation of alcohol-induced mouse cardiomyocytes apoptosis by promoting reactive oxygen species (ROS) accumulation and repressing eNOS expression, which could be potential therapeutic targets for ACM.


2002 ◽  
Vol 80 (8) ◽  
pp. 777-782 ◽  
Author(s):  
Masa-aki Hattori ◽  
Yukio Kato ◽  
Noboru Fujihara

The presence of endothelial nitric oxide synthase (eNOS) has been found in porcine oocytes, but its mRNA and protein levels remain relatively constant during hormonal stimulation. The present study was designed to determine the effect of retinoic acid on eNOS regulation in porcine oocytes during follicle-stimulating hormone (FSH) stimulation. Cumulus–oocyte complexes (COCs), prepared from small antral follicles of immature porcine ovaries, were cultured for 15 h and treated with FSH for an additional 48 h. eNOS mRNA and its protein were analyzed by reverse transcription – polymerase chain reaction and Western blotting, respectively. Retinoic acid had an inhibitory effect on the level of oocyte eNOS mRNA in a dose-dependent manner if COCs were exposed to retinoic acid before FSH stimulation. The inhibition of FSH action was reflected in a decrease in expression of c-fos mRNA. eNOS protein also decreased to approximately 50% of the control after exposure to 10 μM retinoic acid. However, the ability of NO synthesis was abolished in the oocytes prepared from retinoic acid pretreated COCs. These results suggest that retinoic acid has a strong inhibitory action on eNOS mRNA level and NO synthesis in the porcine oocyte.Key words: oocyte, retinoic acid, NO synthesis, eNOS, RT–PCR.


2007 ◽  
Vol 293 (6) ◽  
pp. H3532-H3541 ◽  
Author(s):  
Antonio L'Abbate ◽  
Danilo Neglia ◽  
Cecilia Vecoli ◽  
Michela Novelli ◽  
Virginia Ottaviano ◽  
...  

Transient reduction in coronary perfusion pressure in the isolated mouse heart increases microvascular resistance (paradoxical vasoconstriction) by an endothelium-mediated mechanism. To assess the presence and extent of paradoxical vasoconstriction in hearts from normal and diabetic rats and to determine whether increased heme oxygenase (HO)-1 expression and HO activity, using cobalt protoporphyrin (CoPP), attenuates coronary microvascular response, male Wistar rats were rendered diabetic with nicotinamide/streptozotocin for 2 wk and either CoPP or vehicle was administered by intraperitoneal injection weekly for 3 wk (0.5 mg/100 g body wt). The isolated beating nonworking heart was submitted to transient low perfusion pressure (20 mmHg), and coronary resistance (CR) was measured. During low perfusion pressure, CR increased and was associated with increased lactate release. In diabetic rats, CR was higher, HO-1 expression and endothelial nitric oxide synthase were downregulated, and inducible nitric oxide synthase and O2− were upregulated. After 3 wk of CoPP treatment, HO activity was significantly increased in the heart. Upregulation of HO-1 expression and HO activity by CoPP resulted in the abolition of paradoxical vasoconstriction and a reduction in oxidative ischemic damage. In addition, there was a marked increase in serum adiponectin. Elevated HO-1 expression was associated with increased expression of cardiac endothelial nitric oxide synthase, B-cell leukemia/lymphoma extra long, and phospho activator protein kinase levels and decreased levels of inducible nitric oxide synthase and malondialdehyde. These results suggest a critical role for HO-1 in microvascular tone control and myocardial protection during ischemia in both normal and mildly diabetic rats through the modulation of constitutive and inducible nitric oxide synthase expression and activity, and an increase in serum adiponectin.


2001 ◽  
Vol 280 (5) ◽  
pp. R1269-R1275 ◽  
Author(s):  
Michael J. Solhaug ◽  
Usa Kullaprawithaya ◽  
Xui Q. Dong ◽  
Ke-Wen Dong

The postnatal pattern of renal endothelial nitric oxide synthase (eNOS) is unknown. The purpose of this study was to characterize eNOS expression during maturation and compare this to neuronal NOS (nNOS). The experiments measured whole kidney eNOS mRNA expression by RT-PCR and protein content by Western blot, as well as cortical and medullary protein content in piglets at selected postnatal ages and in adult pigs. Whole kidney eNOS mRNA was compared with nNOS. Whole kidney eNOS expression decreased from the newborn to its lowest at 7 days, returning by 14 days to adult levels. This eNOS mRNA pattern contrasted with nNOS, which was highest at birth, and progressively decreased to its lowest level in the adult. At birth, cortical eNOS protein was greater than medullary, contrasting with the adult pattern of equivalent levels. In conclusion eNOS is developmentally regulated during early renal maturation and may critically participate in renal function during this period. The eNOS developmental pattern differs from nNOS, suggesting that these isoforms may have different regulatory factors and functional contributions in the postnatal kidney.


2003 ◽  
Vol 285 (3) ◽  
pp. R674-R681 ◽  
Author(s):  
Eva Cediel ◽  
David Sanz-Rosa ◽  
M. Pilar Oubiña ◽  
Natalia de las Heras ◽  
Francisco R. González Pacheco ◽  
...  

The study investigated whether the amelioration of endothelial dysfunction by candesartan (2 mg·kg-1·day-1; 10 wk) in spontaneously hypertensive rats (SHR) was associated with modification of hepatic redox system. Systolic arterial pressure (SAP) was higher ( P < 0.05) in SHR than in Wistar-Kyoto rats (WKY) and was reduced ( P < 0.05) by candesartan in both strains. Acetylcholine (ACh) relaxations were smaller ( P < 0.05) and contractions induced by ACh + NG-nitro-l-arginine methyl ester (l-NAME) were greater ( P < 0.05) in SHR than in WKY. Treatment with candesartan enhanced ( P < 0.05) ACh relaxations in SHR and reduced ( P < 0.05) ACh + l-NAME contractions in both strains. Expression of aortic endothelial nitric oxide synthase (eNOS) mRNA was similar in WKY and SHR, and candesartan increased ( P < 0.05) it in both strains. Aortic mRNA expression of the subunit p22phox of NAD(P)H oxidase was higher ( P < 0.05) in SHR than in WKY. Treatment with candesartan reduced ( P < 0.05) p22phox expression only in SHR. Malonyl dialdehyde (MDA) levels were higher ( P < 0.05), and the ratio reduced/oxidized glutathione (GSH/GSSG) as well as glutathione peroxidase activity (GPx) were lower ( P < 0.05) in liver homogenates from SHR than from WKY. Candesartan reduced ( P < 0.05) MDA and increased ( P < 0.05) GSH/GSSG ratio without affecting GPx. Vessel, lumen, and media areas were bigger ( P < 0.05) in SHR than in WKY. Candesartan treatment reduced ( P < 0.05) media area in SHR without affecting vessel or lumen area. The results suggest that hypertension is not only associated with elevation of vascular superoxide anions but with alterations of the hepatic redox system, where ANG II is clearly involved. The results further support the key role of ANG II via AT1 receptors for the functional and structural vascular alterations produced by hypertension.


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