Scavenging free radicals improves endothelial dysfunction in human coronary arteries in vivo

Fasudil Ameliorates Osteoporosis Following Myocardial Infarction by Regulating Cardiac Calcitonin Secretion

We hypothesis that Rho kinase inhibitor fasudil ameliorates osteoporosis following myocardial infarction (MI) by regulating cardiac calcitonin secretion. A mice model of MI and cultured neonatal cardiomyocytes exposed to hypoxia and serum deprivation (H/SD), and fibroblasts exposed to TGF-β were used, respectively. Cardiac function in vivo was assessed with echocardiography. Osteoporosis in vivo was assessed with X-ray and micro-CT. In vivo and in vitro studies used histological and immunohistochemical techniques, along with western blots. In mice post-MI, fasudil ameliorates the microstructure and bone metabolism of the lumbar, improved cardiac function, and attenuated myocardial fibrosis. In vitro, fasudil or αCGRP could effectively inhibit the proliferation of primary fibroblasts treated with TGF-β. Moreover, fasudil ameliorates the cardiac calcitonin secretion induced by MI in vivo or by H/SD in vitro. Our findings suggest that fasudil improved MI-induced osteoporosis by promoting cardiac secreting calcitonin.

A community-based study of the relationship between coronary artery disease and osteoporosis in Chinese postmenopausal women

BACKGROUND

Menopause is associated with an increased risk for osteoporosis (OP) and coronary artery disease (CAD). The goal of this study was to seek the possible relationship between CAD and OP in Chinese postmenopausal women.

PATIENTS AND METHODS

The total of 1825 participants with complete records were available for data analysis in this study. CAD was diagnosed if any one of the following was present: (i) history and/or treatment for angina and/or myocardial infarction; (ii) history of coronary artery revascularization procedures and/or coronary angiography with 50% or more stenosis in one or more of the major coronary arteries; and (iii) regional wall-motion abnormalities on rest echocardiography. OP was defined as T-score less than -2.5. Multiple regression models after controlling for confounding factors were performed to detect their relationships.

RESULTS

The multiple variable linear regression analyses failed to show a significant association between CAD and T-score. However, the multivariate logistic regression analyses after adjustment for relevant confounding factors detected significant associations between CAD and OP.

CONCLUSION

The present study provided data suggesting that CAD was independently and significantly associated with OP. The prevalence of OP was more frequent in Chinese postmenopausal women with CAD.

Telmisartan inhibits the proinflammatory effects of homocysteine on human endothelial cells through activation of the peroxisome proliferator-activated receptor-δ pathway

The aim of this study was to investigate the inhibition capacity of telmisartan to endothelial inflammation induced by homocysteine (Hcy) and discuss the proposed mechanism in vitro. Human umbilical vein endothelial cells (HUVECs) were prepared by collagenase digestion and cultured in vitro. An increase in monocyte chemoattractant protein-1 (MCP-1) and vascular cell adhesion molecule-1 (VCAM-1) was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) as markers of Hcy-induced endothelial inflammation. HL-60 cell adhesion to HUVECs was measured by rose bengal staining. Nuclear, cytosolic and total nuclear transcription factor-κB (NF-κB) p65 levels were analyzed by western blotting. Peroxisome proliferator-activated receptor-δ (PPARδ) expression by HUVECs exposed to Hcy with or without telmisartan pretreatment was analyzed by RT-PCR and western blotting. Hcy significantly increased the levels of MCP-1 mRNA, VCAM-1 mRNA and monocyte binding to HUVECs. These effects were significantly attenuated by pretreatment with telmisartan and PPARδ agonists. The effect of telmisartan was inhibited by PPARδ antagonists. The Hcy-mediated downregulation of PPARδ mRNA and protein of HUVECs was inhibited by telmisartan. Hcy-mediated upregulation of NF-κB p65 protein levels in nuclear extracts was inhibited by telmisartan and PPARδ agonists. In conclusion, telmisartan exerts potent anti-inflammatory effects in endothelial cells, probably via a binary mechanism involving PPARδ activation and inhibition of the nuclear translocation of NF-κB.

The efficacy of edaravone (radicut), a free radical scavenger, for cardiovascular disease

Edaravone was originally developed as a potent free radical scavenger, and has been widely used to treat acute ischemic stroke in Japan since 2001. Free radicals play an important role in the pathogenesis of a variety of diseases, such as cardiovascular diseases and stroke. Therefore, free radicals may be targets for therapeutic intervention in these diseases. Edaravone shows protective effects on ischemic insults and inflammation in the heart, vessel, and brain in experimental studies. As well as scavenging free radicals, edaravone has anti-apoptotic, anti-necrotic, and anti-cytokine effects in cardiovascular diseases and stroke. Edaravone has preventive effects on myocardial injury following ischemia and reperfusion in patients with acute myocardial infarction. Edaravone may represent a new therapeutic intervention for endothelial dysfunction in the setting of atherosclerosis, heart failure, diabetes, or hypertension, because these diseases result from oxidative stress and/or cytokine-induced apoptosis. This review evaluates the potential of edaravone for treatment of cardiovascular disease, and covers clinical and experimental studies conducted between 1984 and 2013. We propose that edaravone, which scavenges free radicals, may offer a novel option for treatment of cardiovascular diseases. However, additional clinical studies are necessary to verify the efficacy of edaravone.

Therapeutic time window for edaravone treatment of traumatic brain injury in mice

Traumatic brain injury (TBI) is a major cause of death and disability in young people. No effective therapy is available to ameliorate its damaging effects. Our aim was to investigate the optimal therapeutic time window of edaravone, a free radical scavenger which is currently used in Japan. We also determined the temporal profile of reactive oxygen species (ROS) production, oxidative stress, and neuronal death. Male C57Bl/6 mice were subjected to a controlled cortical impact (CCI). Edaravone (3.0 mg/kg), or vehicle, was administered intravenously at 0, 3, or 6 hours following CCI. The production of superoxide radicals (O₂^∙−) as a marker of ROS, of nitrotyrosine (NT) as an indicator of oxidative stress, and neuronal death were measured for 24 hours following CCI. Superoxide radical production was clearly evident 3 hours after CCI, with oxidative stress and neuronal cell death becoming apparent after 6 hours. Edaravone administration after CCI resulted in a significant reduction in the injury volume and oxidative stress, particularly at the 3-hour time point. Moreover, the greatest decrease in O₂^∙− levels was observed when edaravone was administered 3 hours following CCI. These findings suggest that edaravone could prove clinically useful to ameliorate the devastating effects of TBI.

Suppression of high lipid diet induced by atherosclerosis sarpogrelate

Sarpogrelate (SP), a serotonin (5-HT2A) receptor antagonist, is used as an anti-platelet agent for the treatment of some vascular diseases. SP has been reported to inhibit 5-HT induced coronary artery spasm, increase in intracellular calcium and smooth muscle cells proliferation. This study was undertaken to test that SP suppresses the development of atherosclerosis due to high cholesterol diet (HCD) by decreasing blood viscosity and oxidative stress. For this purpose, 29 rabbits were divided into four groups: control group (normal diet); normal diet group with SP at the dose of 5 mg/kg/day; HCD group fed 1% cholesterol; and HCD group with SP at the dose of 5 mg/kg/day. After 90 days of the experiment, blood samples were collected and the animals were killed; the thoracic aorta was stained by the Oil Red O staining method. The results indicate that plasma levels of cholesterol, triglycerides and malondialdehyde were increased in rabbits fed HCD. Plasma viscosity and whole blood viscosity were also higher in the HCD group than that in normal diet group. Treatment with SP prevented these alterations induced by HCD whereas this agent had no significant effect in rabbits fed normal diet. Morphological examination of the aorta revealed that SP treatment prevented the formation of foam cells and atherosclerotic plaque. It is suggested that the beneficial effects of SP in atherosclerosis may be due to actions on blood viscosity, lipid levels and oxidative stress.

Edaravone increases regional cerebral blood flow after traumatic brain injury in mice

Traumatic brain injury (TBI) is a major cause of preventable death and serious morbidity, with subsequent low cerebral blood flow (CBF) considered to be associated with poor prognosis. In the present study, we demonstrated the effect of the free radical scavenger edaravone on regional CBF (rCBF) after TBI. Male mice (C57/BL6) were subjected to TBI using a controlled cortical impactor device. Immediately after TBI, the animals were intravenously administered 3.0 mg/kg of edaravone or a vehicle saline solution. Two-dimensional rCBF images were acquired before and 24 h post-TBI, and were quantified in the ipsilateral and contralateral hemispheres (n = 5 animals per group). CBF in the vehicle-treated animals decreased broadly over the ipsilateral hemisphere, with the region of low rCBF spreading from the frontal cortex to the occipital lobe. The zone of lowest rCBF matched that of the contusion area. The mean rCBF at 24 h for a defined elliptical region between the bregma and lambda was 73.7 ± 5.8 %. In comparison, the reduction of rCBF in edaravone-treated animals was significantly attenuated (93.4 ± 5.7 %, p < 0.05). The edaravone-treated animals also exhibited higher rCBF in the contralateral hemisphere compared with that seen in -vehicle-treated animals. It is suggested that edaravone reduces neuronal damage by scavenging reactive oxygen species (ROS) and by maintaining intact the autoregulation of the cerebral vasculature.