scholarly journals Impaired endothelial dysfunction in diabetes mellitus rats was restored by oral administration of prostaglandin I2 analogue

2002 ◽  
Vol 175 (1) ◽  
pp. 217-223 ◽  
Author(s):  
K Matsumoto ◽  
R Morishita ◽  
N Tomita ◽  
A Moriguchi ◽  
K Yamasaki ◽  
...  

We have previously reported that a decrease in hepatocyte growth factor (HGF), which has many protective functions against endothelial damage by high d-glucose, might be a trigger of endothelial injury. However, the regulation of vascular HGF in diabetes mellitus (DM) has not been clarified in vivo, although vascular disease is frequently observed in DM patients. In addition, our previous report revealed that a prostaglandin I(2) (PGI(2)) analogue prevented endothelial cell death through the induction of vascular HGF production in cultured human epithelial cells. Thus, in this study, we examined the effects of a PGI(2) analogue in the regulation of the local HGF system using DM rats. A PGI(2) analogue (beraprost sodium; 300 and 600 micro g/kg per day) or vehicle was administered to 16-week-old DM rats induced by administration of streptozotocin for 28 days. Endothelial function was evaluated by the vasodilator response to acetylcholine, and the expression of vascular HGF mRNA was measured by Northern blotting. Of importance, expression of HGF mRNA was significantly decreased in the blood vessels of DM rats as compared with non-DM (P<0.01). In addition, the in vitro vasodilator response of the abdominal aorta to acetylcholine was markedly impaired in DM rats. Importantly, the vasodilator response was restored by PGI(2) treatment in a dose-dependent manner (P<0.01), whereas N(omega)-nitro-l-arginine methyl ester inhibited the restoration of endothelial function. Of particular interest, vascular HGF mRNA and protein were significantly increased in the blood vessels of DM rats treated with PGI(2) as compared with vehicle. Similarly, an increase in HGF protein was also confirmed by immunohistochemical analysis. In addition, the specific HGF receptor, c-met, was also increased by PGI(2) treatment. Overall, this study demonstrated that treatment with a PGI(2) analogue restored endothelial dysfunction in DM rats, accompanied by the induction of vascular HGF and c-met expression. Increased local vascular HGF production by a PGI(2) analogue may prevent endothelial injury, potentially resulting in the improvement of endothelial dysfunction.

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Nadia Calabriso ◽  
Antonio Gnoni ◽  
Eleonora Stanca ◽  
Alessandro Cavallo ◽  
Fabrizio Damiano ◽  
...  

Mitochondria are fundamental organelles producing energy and reactive oxygen species (ROS); their impaired functions play a key role in endothelial dysfunction. Hydroxytyrosol (HT), a well-known olive oil antioxidant, exerts health benefits against vascular diseases by improving endothelial function. However, the HT role in mitochondrial oxidative stress in endothelial dysfunction is not clear yet. To investigate the HT effects on mitochondrial ROS production in the inflamed endothelium, we used an in vitro model of endothelial dysfunction represented by cultured endothelial cells, challenged with phorbol myristate acetate (PMA), an inflammatory, prooxidant, and proangiogenic agent. We found that the pretreatment of endothelial cells with HT (1–30 μmol/L) suppressed inflammatory angiogenesis, a crucial aspect of endothelial dysfunction. The HT inhibitory effect is related to reduced mitochondrial superoxide production and lipid peroxidation and to increased superoxide dismutase activity. HT, in a concentration-dependent manner, improved endothelial mitochondrial function by reverting the PMA-induced reduction of mitochondrial membrane potential, ATP synthesis, and ATP5β expression. In PMA-challenged endothelial cells, HT also promoted mitochondrial biogenesis through increased mitochondrial DNA content and expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha, nuclear respiratory factor-1, and mitochondrial transcription factor A. These results highlight that HT blunts endothelial dysfunction and pathological angiogenesis by ameliorating mitochondrial function, thus suggesting HT as a potential mitochondria-targeting antioxidant in the inflamed endothelium.


2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Rodrigo O. Marañón ◽  
Claudio Joo Turoni ◽  
Maria Sofia Karbiner ◽  
Nicolas Salas ◽  
Maria Peral de Bruno

Nonischemic 5/6 nephrectomized rat (NefR) is a model of chronic kidney disease. However, little is known about vascular dysfunction and its relation with hypertension in NefR.Aims. To evaluate possible alterations of endothelial function, NO-bioavailability, and basal tone in aorta from NefR and the role of oxidative stress. Sprague Dawley rats were divided into sham rats (SR), NefR, and NefR treated with tempol (NefR-T). Mean arterial pressure (MAP) and renal function were determined. In isolated aortic rings the following was measured: 1-endothelial function, 2-basal tone, 3-NO levels, 4-membrane potential (MP), and 5-oxidative stress. NefR increased MAP (SR: 119 ± 4 mmHg;n=7; NefR: 169 ± 6;n=8;P<0.001). Tempol did not modify MAP (NefR-T: 168 ± 10;n=6;P<0.001). NefR showed endothelial dysfunction, increased basal tone and decreased NO levels (SR: 32 ± 2 nA;n=7, NefR: 10 ± 2;n=8;P<0.001). In both in vitro and in vivo tempol improves basal tone, NO levels, and MP. Oxidative stress in NefR was reverted in NefR-T. We described, for the first time, that aorta from NefR presented increased basal tone related to endothelial dysfunction and decreased NO-bioavailability. The fact that tempol improves NO-contents and basal tone, without decrease MAP, indicates that oxidative stress could be implicated early and independently to hypertension, in the vascular alterations.


2016 ◽  
Vol 310 (11) ◽  
pp. L1233-L1242 ◽  
Author(s):  
Jia-Xin Ye ◽  
Shan-Shan Wang ◽  
Min Ge ◽  
Dong-Jin Wang

Endothelial dysfunction plays a principal role in the pathogenesis of pulmonary arterial hypertension (PAH), which is a fatal disease with limited effective clinical treatments. Mitochondrial dysregulation and oxidative stress are involved in endothelial dysfunction. Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α) is a key regulator of cellular energy metabolism and a master regulator of mitochondrial biogenesis. However, the roles of PGC-1α in hypoxia-induced endothelial dysfunction are not completely understood. We hypothesized that hypoxia reduces PGC-1α expression and leads to endothelial dysfunction in hypoxia-induced PAH. We confirmed that hypoxia has a negative impact on endothelial PGC-1α in experimental PAH in vitro and in vivo. Hypoxia-induced PGC-1α inhibited the oxidative metabolism and mitochondrial function, whereas sustained PGC-1α decreased reactive oxygen species (ROS) formation, mitochondrial swelling, and NF-κB activation and increased ATP formation and endothelial nitric oxide synthase (eNOS) phosphorylation. Furthermore, hypoxia-induced changes in the mean pulmonary arterial pressure and right heart hypertrophy were nearly normal after intervention. These results suggest that PGC-1α is associated with endothelial function in hypoxia-induced PAH and that improved endothelial function is associated with improved cellular mitochondrial respiration, reduced inflammation and oxygen stress, and increased PGC-1α expression. Taken together, these findings indicate that PGC-1α may be a new therapeutic target in PAH.


1995 ◽  
Vol 82 (1) ◽  
pp. 221-235 ◽  
Author(s):  
W. A. Boyle ◽  
G. M. Maher

Background Whether volatile anesthetics produce changes in vascular resistance and blood flow because of direct effects on vascular tissue is unclear. Direct vasoconstricting and vasodilating actions have been demonstrated in isolated conductance arteries in vitro, but there is little information regarding direct effects on the small vessels that mediate resistance and flow changes in vivo. Methods We investigated the actions of halothane on 50-200 microM branches of the rat mesenteric artery that were cannulated and studied in vitro. The vessels were pressurized to 60 mmHg, and vascular dimensions were continuously monitored using a computer-based real-time image analysis system. The vessel bath was perfused with HCO3(-)-buffered saline (37 degrees C) equilibrated with 95% O2/5% CO2 (+/- halothane). The vascular endothelium was mechanically removed before cannulation in some vessels. Results In unstimulated vessels, halothane had a concentration-dependent vasoconstricting action (EC50 = 0.45 mM approximately 1.5 vol% at 37 degrees C) that was largely transient and was similar to that produced by caffeine. Both halothane and caffeine constrictions were unaffected by bath [Ca2+], nifedipine (1 microM) or Cd2+ (100 microM) and were abolished by ryanodine (10 microM). In addition, caffeine responses were attenuated by halothane in a concentration-dependent manner (EC50 = 1.6 mM). In vessels preconstricted with KCl (40 mM) or phenylephrine (10(-6) M), halothane produced transient constriction followed by concentration-dependent vasodilation. Ryanodine, which abolished halothane constrictions, had little effect on the amplitude of KCl- or phenylephrine-induced constrictions or the vasodilating action of halothane. Removal of the endothelium likewise had little effect on the vasoconstricting or the vasodilating actions of halothane in unstimulated, KCl- or phenylephrine-constricted vessels. Halothane completely relaxed KCl and phenylephrine constrictions with EC50 values of 0.36 mM (1.2% at 37 degrees C) and 0.75 mM (2.5%), respectively, in intact vessels before ryanodine; 0.25 mM (0.8%) and 0.59 mM (1.9%) in intact vessels after ryanodine; and 0.52 mM (1.7%) and 0.67 mM (2.2%) in endothelium-denuded vessels. Conclusions Halothane has endothelium-independent vasoconstricting and vasodilating actions in isolated mesenteric resistance blood vessels. The vasoconstricting action appears to involve halothane-induced Ca2+ release from caffeine/ryanodine-sensitive intracellular store(s). The vasodilating action in phenylephrine- or KC1-constricted vessels is independent of the Ca(2+)-releasing action and most likely involves an effect(s) on sarcolemmal-dependent Ca2+ signaling (e.g., extracellular Ca2+ influx) and/or Ca2+ activation of contractile proteins. The magnitude of both the vasoconstricting and the vasodilating actions of halothane in these vessels at clinically relevant concentrations suggests these direct actions contribute to the overall cardiovascular effects of halothane in vivo.


2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Qingsong Jin ◽  
Liangyan Lin ◽  
Tiantian Zhao ◽  
Xiaoyan Yao ◽  
Yaqin Teng ◽  
...  

Abstract Background Diabetes mellitus (DM), a most common chronic disease, is featured with impaired endothelial function and bioavailability of nitric oxide (NO), while E3 ubiquitin ligase appears to alleviate endothelial dysfunction as a promising option for DM treatment. Herein, we aimed to determine whether E3 ubiquitin ligase casitas B-lineage lymphoma (Cbl) alleviates endothelial dysfunction in DM rats by JAK2/STAT4 pathway. Methods A rat model of DM was developed through intraperitoneal injection of streptozotocin, followed by collection of aortic tissues to determine the expression of Cbl, JAK2, runt-related transcription factor 3 (Runx3) and STAT4. Human umbilical vein endothelial cells (HUVECs) were cultured in high glucose (HG) condition to induce DM as an in vitro model. With gain- and loss-function method, we assessed the aberrantly expressed Cb1 on endothelial dysfunction, NO production and apoptosis of HUVECs. Results Cbl was reduced in DM rat tissues and HG-induced HUVECs, where JAK2, Runx3 and STAT4 were elevated. It was found that overexpression of Cbl alleviated endothelial dysfunction by increasing NO production and restoring vasodilation and suppressing apoptosis of HUVECs. Mechanistically, Cb1 enhanced JAK2 ubiquitination and decreased JAK2 and STAT4 expression, where STAT4 improved Runx3 expression by regulating histone H3 lysine 4 trimethylation level. Overexpression of JAK2 and STAT4, or Runx3 increased apoptosis of HUVECs, abrogating the effect of Cb1 on endothelial function. Conclusion In conclusion, Cbl alleviates endothelial dysfunction by inactivation of the JAK2/STAT4 pathway and inhibition of Runx3 expression in DM. These evidence might underlie novel Cbl-based treatment against DM in the future.


2000 ◽  
Vol 278 (3) ◽  
pp. R628-R639 ◽  
Author(s):  
Zhi-Wei Yang ◽  
Asefa Gebrewold ◽  
Maja Nowakowski ◽  
Bella T. Altura ◽  
Burton M. Altura

In vitro extracellular Mg2+ concentration ([Mg2+]0) produces endothelium-dependent and endothelium-independent relaxations in rat aorta in a concentration-dependent manner. These relaxant effects of Mg2+ on intact rat aortic rings, but not denuded rat aortic rings, were suppressed by either N G-monomethyl-l-arginine (l-NMMA), N ω-nitro-l-arginine methyl ester (l-NAME), or methylene blue. The inhibitory effects of l-NMMA and l-NAME could be reversed partly by l-arginine. [Mg2+]0-induced dilatation in vivo in rat mesenteric arterioles and venules was almost completely inhibited by N G-nitro-l-arginine andl-NMMA. Removal of extracellular Ca2+concentration ([Ca2+]0) or buffering intracellular Ca2+ concentration in endothelial cells, with 10 μM 1,2-bis(2-aminophenoxy)ethane- N, N, N′, N′-tetraacetic acid-AM, markedly attenuated the relaxant effects of Mg2+. Mg2+ produced nitric oxide (NO) release from the intact aortic rings in a concentration-dependent manner. Removal of [Ca2+]0 diminished the increased NO release induced by elevated levels of [Mg2+]0. In vivo infusion of increasing doses (1–30 μM/min) of MgSO4, directly into the femoral veins of anesthetized rats, elicited significant concentration-dependent sustained increases in serum total Mg and concomitant decreases in arterial blood pressure. Before and after employment of various doses of MgSO4, intravenous administration of either l-NMMA (10 mg/kg) orl-NAME (10 mg/kg) increased (i.e., reversed) the MgSO4-lowered blood pressure markedly, and intravenous injection of l-arginine restored partially the increased blood pressure effects of both l-NMMA andl-NAME. Our results suggest that 1) small blood vessels are very dependent on NO release for Mg2+dilatations and 2) the endothelium-dependent relaxation induced by extracellular Mg2+ is mediated by release of endothelium-derived relaxing factor-NO from the endothelium, and requires Ca2+ and formation of guanosine 3′,5′-cyclic monophosphate.


2003 ◽  
Vol 305 (1) ◽  
pp. 114-122 ◽  
Author(s):  
S. Dhein ◽  
A. Kabat ◽  
A. Olbrich ◽  
P. Rösen ◽  
H. Schröder ◽  
...  

1986 ◽  
Vol 113 (1_Suppl) ◽  
pp. S120-S121
Author(s):  
TH. LINN ◽  
H. GERMANN ◽  
B. HERING ◽  
R. BRETZEL ◽  
K. FEDERLIN

2019 ◽  
Vol 26 (7) ◽  
pp. 494-501 ◽  
Author(s):  
Sameer Suresh Bhagyawant ◽  
Dakshita Tanaji Narvekar ◽  
Neha Gupta ◽  
Amita Bhadkaria ◽  
Ajay Kumar Gautam ◽  
...  

Background: Diabetes and hypertension are the major health concern and alleged to be of epidemic proportions. This has made it a numero uno subject at various levels of investigation. Glucosidase inhibitor provides the reasonable option in treatment of Diabetes Mellitus (DM) as it specifically targets post prandial hyperglycemia. The Angiotensin Converting Enzyme (ACE) plays an important role in hypertension. Therefore, inhibition of ACE in treatment of elevated blood pressure attracts special interest of the scientific community. Chickpea is a food legume and seeds contain carbohydrate binding protein- a lectin. Some of the biological properties of this lectin hitherto been elucidated. Methods: Purified by ion exchange chromatography, chickpea lectin was tested for its in vitro antioxidant, ACE-I inhibitory and anti-diabetic characteristic. Results: Lectin shows a characteristic improvement over the synthetic drugs like acarbose (oral anti-diabetic drug) and captopril (standard antihypertensive drug) when, their IC50 values are compared. Lectin significantly inhibited α-glucosidase and α-amylase in a concentration dependent manner with IC50 values of 85.41 ± 1.21 ҝg/ml and 65.05 ± 1.2 µg/ml compared to acarbose having IC50 70.20 ± 0.47 value of µg/ml and 50.52 ± 1.01 µg/ml respectively. β-Carotene bleaching assay showed antioxidant activity of lectin (72.3%) to be as active as Butylated Hydroxylanisole (BHA). In addition, lectin demonstrated inhibition against ACE-I with IC50 value of 57.43 ± 1.20 µg/ml compared to captopril. Conclusion: Lectin demonstrated its antioxidant character, ACE-I inhibition and significantly inhibitory for α-glucosidase and α-amylase seems to qualify as an anti-hyperglycemic therapeutic molecule. The biological effects of chickpea lectin display potential for reducing the parameters of medically debilitating conditions. These characteristics however needs to be established under in vivo systems too viz. animals through to humans.


Cells ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1731
Author(s):  
Yu Maw Htwe ◽  
Huashan Wang ◽  
Patrick Belvitch ◽  
Lucille Meliton ◽  
Mounica Bandela ◽  
...  

Lung endothelial dysfunction is a key feature of acute lung injury (ALI) and clinical acute respiratory distress syndrome (ARDS). Previous studies have identified the lipid-generating enzyme, group V phospholipase A2 (gVPLA2), as a mediator of lung endothelial barrier disruption and inflammation. The current study aimed to determine the role of gVPLA2 in mediating lung endothelial responses to methicillin-resistant Staphylococcus aureus (MRSA, USA300 strain), a major cause of ALI/ARDS. In vitro studies assessed the effects of gVPLA2 inhibition on lung endothelial cell (EC) permeability after exposure to heat-killed (HK) MRSA. In vivo studies assessed the effects of intratracheal live or HK-MRSA on multiple indices of ALI in wild-type (WT) and gVPLA2-deficient (KO) mice. In vitro, HK-MRSA increased gVPLA2 expression and permeability in human lung EC. Inhibition of gVPLA2 with either the PLA2 inhibitor, LY311727, or with a specific monoclonal antibody, attenuated the barrier disruption caused by HK-MRSA. LY311727 also reduced HK-MRSA-induced permeability in mouse lung EC isolated from WT but not gVPLA2-KO mice. In vivo, live MRSA caused significantly less ALI in gVPLA2 KO mice compared to WT, findings confirmed by intravital microscopy assessment in HK-MRSA-treated mice. After targeted delivery of gVPLA2 plasmid to lung endothelium using ACE antibody-conjugated liposomes, MRSA-induced ALI was significantly increased in gVPLA2-KO mice, indicating that lung endothelial expression of gVPLA2 is critical in vivo. In summary, these results demonstrate an important role for gVPLA2 in mediating MRSA-induced lung EC permeability and ALI. Thus, gVPLA2 may represent a novel therapeutic target in ALI/ARDS caused by bacterial infection.


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