Description:
Atherosclerosis is characterized by the narrowing of the arterial lumen due to subendothelial lipid accumulation, with hypercholesterolemia being a major risk factor. Despite the recent advances in effective lipid-lowering therapies, atherosclerosis remains the leading cause of mortality globally, highlighting the need for additional therapeutic strategies. Accumulating evidence suggests that the sympathetic nervous system plays an important role in atherosclerosis. In this article, we reviewed the sympathetic innervation in the vasculature, norepinephrine synthesis and metabolism, sympathetic activity measurement, and common signaling pathways of sympathetic activation. The focus of this paper was to review the effectiveness of pharmacological antagonists or agonists of adrenoceptors (
Description:
Atherosclerosis is characterized by the narrowing of the arterial lumen due to subendothelial lipid accumulation, with hypercholesterolemia being a major risk factor. Despite the recent advances in effective lipid-lowering therapies, atherosclerosis remains the leading cause of mortality globally, highlighting the need for additional therapeutic strategies. Accumulating evidence suggests that the sympathetic nervous system plays an important role in atherosclerosis. In this article, we reviewed the sympathetic innervation in the vasculature, norepinephrine synthesis and metabolism, sympathetic activity measurement, and common signaling pathways of sympathetic activation. The focus of this paper was to review the effectiveness of pharmacological antagonists or agonists of adrenoceptors (
An improved 3-(4,5-dmethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl )-2H-tetrazolium proliferation assay to overcome the interference of hydralazine
Description:
The MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay is one of the most commonly used assays to assess cell proliferation and cytotoxicity, but is subject to interference by testing compounds. Hydralazine, an antihypertensive drug, is commonly investigated in multiple fields such as heart failure, cancer, and blood pressure research. This study reported interference of the MTS assay by hydralazine and a simple modification overcoming this interference. Vascular smooth muscle cells were cultured in the presence or absence of hydralazine (0, 10, 50,100, and 500 mu M) for 2 or 24 h. Cell numbers were analyzed using MTS, trypan blue exclusion, or microscopic assays. A modified version of the standard MTS assay was established, in which an additional step was added replacing the test medium, containing hydralazine, with fresh culture medium immediately before the addition of the MTS reagent. Culture with hydralazine at concentrations of 50, 100, and 500 mu M for 2 h increased absorbance (p< 0.05) in the standard MTS assay, whereas microscopy suggested no change in cell numbers. Culture with 500 mu m hydralazine for 24 h increased absorbance (p< 0.05) in the standard MTS assay, however, trypan blue exclusion and microscopy suggested a decrease in cell numbers. In a cell-free system, hydralazine (>= 10 mu M) increased absorbance in a concentration-dependent manner. The modified MTS assay produced results consistent with trypan blue exclusion and microscopy. In conclusion, a simple modification of the standard MTS assay overcame the interference of hydralazine and may be useful to avoid interference from other tested compounds.
Description:
The MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay is one of the most commonly used assays to assess cell proliferation and cytotoxicity, but is subject to interference by testing compounds. Hydralazine, an antihypertensive drug, is commonly investigated in multiple fields such as heart failure, cancer, and blood pressure research. This study reported interference of the MTS assay by hydralazine and a simple modification overcoming this interference. Vascular smooth muscle cells were cultured in the presence or absence of hydralazine (0, 10, 50,100, and 500 mu M) for 2 or 24 h. Cell numbers were analyzed using MTS, trypan blue exclusion, or microscopic assays. A modified version of the standard MTS assay was established, in which an additional step was added replacing the test medium, containing hydralazine, with fresh culture medium immediately before the addition of the MTS reagent. Culture with hydralazine at concentrations of 50, 100, and 500 mu M for 2 h increased absorbance (p< 0.05) in the standard MTS assay, whereas microscopy suggested no change in cell numbers. Culture with 500 mu m hydralazine for 24 h increased absorbance (p< 0.05) in the standard MTS assay, however, trypan blue exclusion and microscopy suggested a decrease in cell numbers. In a cell-free system, hydralazine (>= 10 mu M) increased absorbance in a concentration-dependent manner. The modified MTS assay produced results consistent with trypan blue exclusion and microscopy. In conclusion, a simple modification of the standard MTS assay overcame the interference of hydralazine and may be useful to avoid interference from other tested compounds.
Description:
Ewen et al. recently reported in the journal Hypertension that they investigated, for the first time, the effect of renal denerva tion on blood pressure in 63 patients with isolated systolic hypertension (Ewen et al., 2014). The authors concluded that renal denervation reduced office and ambula- tory blood pressure in patients with iso- lated systolic hypertension (Ewen et al., 2014). However, this conclusion may not be drawn, as renal denervation may not decrease ambulatory blood pressure in these patients. The potential risk of renal denervation may overweigh its benefit in patients with isolated systolic hypertension. Therefore, adjusted drug treatment may be recommended to these patients before renal denervation.
Description:
Ewen et al. recently reported in the journal Hypertension that they investigated, for the first time, the effect of renal denerva tion on blood pressure in 63 patients with isolated systolic hypertension (Ewen et al., 2014). The authors concluded that renal denervation reduced office and ambula- tory blood pressure in patients with iso- lated systolic hypertension (Ewen et al., 2014). However, this conclusion may not be drawn, as renal denervation may not decrease ambulatory blood pressure in these patients. The potential risk of renal denervation may overweigh its benefit in patients with isolated systolic hypertension. Therefore, adjusted drug treatment may be recommended to these patients before renal denervation.
Description:
The association between constipation and cardiovascular risk is unclear. This population-level matched cohort study compared the association of constipation with hypertension and incident cardiovascular events in 541,172 hospitalized patients aged
Description:
The association between constipation and cardiovascular risk is unclear. This population-level matched cohort study compared the association of constipation with hypertension and incident cardiovascular events in 541,172 hospitalized patients aged
Description:
Objective-Sclerostin (SOST) has been identified as an important regulator of bone formation; however, it has not been previously implicated in arterial disease. The aim of this study was to assess the role of SOST in aortic aneurysm (AA) and atherosclerosis using human samples, a mouse model, and in vitro investigations. Approach and Results-SOST protein was downregulated in human and mouse AA samples compared with controls. Transgenic introduction of human SOST in apolipoprotein E-deficient (ApoE(-/-)) mice (SOSTTg. ApoE(-/-)) and administration of recombinant mouse Sost inhibited angiotensin II-induced AA and atherosclerosis. Serum concentrations of several proinflammatory cytokines were significantly reduced in SOSTTg. ApoE(-/-) mice. Compared with controls, the aortas of mice receiving recombinant mouse Sost and SOSTTg. ApoE(-/-) mice showed reduced matrix degradation, reduced elastin breaks, and preserved collagen. Decreased inflammatory cell infiltration and a reduction in the expression of wingless-type mouse mammary virus integration site/beta-catenin responsive genes, including matrix metalloproteinase-9, osteoprotegerin, and osteopontin, were observed in the aortas of SOSTTg. ApoE(-/-) mice. SOST expression was downregulated and the winglesstype mouse mammary virus integration site/beta-catenin pathway was activated in human AA samples. The cytosinephosphate- guanine islands in the SOST gene promoter showed significantly higher methylation in human AA samples compared with controls. Incubation of vascular smooth muscle cells with the demethylating agent 5-azacytidine resulted in upregulation of SOST, suggesting that SOST is epigenetically regulated. Conclusions-This study identifies that SOST is expressed in the aorta and downregulated in human AA possibly because of epigenetic silencing. Upregulating SOST inhibits AA and atherosclerosis development, with potential important implications for treating these vascular diseases.
Description:
Objective-Sclerostin (SOST) has been identified as an important regulator of bone formation; however, it has not been previously implicated in arterial disease. The aim of this study was to assess the role of SOST in aortic aneurysm (AA) and atherosclerosis using human samples, a mouse model, and in vitro investigations. Approach and Results-SOST protein was downregulated in human and mouse AA samples compared with controls. Transgenic introduction of human SOST in apolipoprotein E-deficient (ApoE(-/-)) mice (SOSTTg. ApoE(-/-)) and administration of recombinant mouse Sost inhibited angiotensin II-induced AA and atherosclerosis. Serum concentrations of several proinflammatory cytokines were significantly reduced in SOSTTg. ApoE(-/-) mice. Compared with controls, the aortas of mice receiving recombinant mouse Sost and SOSTTg. ApoE(-/-) mice showed reduced matrix degradation, reduced elastin breaks, and preserved collagen. Decreased inflammatory cell infiltration and a reduction in the expression of wingless-type mouse mammary virus integration site/beta-catenin responsive genes, including matrix metalloproteinase-9, osteoprotegerin, and osteopontin, were observed in the aortas of SOSTTg. ApoE(-/-) mice. SOST expression was downregulated and the winglesstype mouse mammary virus integration site/beta-catenin pathway was activated in human AA samples. The cytosinephosphate- guanine islands in the SOST gene promoter showed significantly higher methylation in human AA samples compared with controls. Incubation of vascular smooth muscle cells with the demethylating agent 5-azacytidine resulted in upregulation of SOST, suggesting that SOST is epigenetically regulated. Conclusions-This study identifies that SOST is expressed in the aorta and downregulated in human AA possibly because of epigenetic silencing. Upregulating SOST inhibits AA and atherosclerosis development, with potential important implications for treating these vascular diseases.
Description:
Methanol, ethanol and formalin are commonly used as fixatives to preserve biological tissues from decay in the preparation of histological sections. Fixation of the inner layers of the tissue depends on the ability of the fixative to diffuse into the tissue. It is unknown whether methanol penetrates tissues at similar rates to other fixatives. This study aimed to compare the penetration rates of methanol, ethanol and formalin into bovine heart and liver tissues. The penetration distance and tissue shrinkage or expansion were measured by analysing the digital images of tissue before and after immersion in different fixatives for 1, 2, 6 or 10 h. Data were analysed using two-way ANOVA, followed by Bonferroni’s post-hoc test. The penetration distance of methanol was significantly greater in both heart and liver tissues compared with that of ethanol (N=4, P<0.001). Methanol or ethanol immersion led to similar shrinkage of both tissues (P>0.05). The penetration rate of formalin was similar to that of ethanol in both tissues however it was significantly slower than methanol (N=4, P<0.005 in the heart; P<0.001 in the liver). The mean penetration coefficients of methanol, formalin and ethanol in the heart tissue were 2.609, 1.994 and 1.801, respectively, and 3.012, 2.153 and 2.113, respectively, in the liver tissue. The penetration coefficient of methanol was significantly greater than that of ethanol or formalin in both tissues (P<0.001 for each comparison). In conclusion, methanol penetrates tissue significantly faster than ethanol and formalin.
Description:
Methanol, ethanol and formalin are commonly used as fixatives to preserve biological tissues from decay in the preparation of histological sections. Fixation of the inner layers of the tissue depends on the ability of the fixative to diffuse into the tissue. It is unknown whether methanol penetrates tissues at similar rates to other fixatives. This study aimed to compare the penetration rates of methanol, ethanol and formalin into bovine heart and liver tissues. The penetration distance and tissue shrinkage or expansion were measured by analysing the digital images of tissue before and after immersion in different fixatives for 1, 2, 6 or 10 h. Data were analysed using two-way ANOVA, followed by Bonferroni’s post-hoc test. The penetration distance of methanol was significantly greater in both heart and liver tissues compared with that of ethanol (N=4, P<0.001). Methanol or ethanol immersion led to similar shrinkage of both tissues (P>0.05). The penetration rate of formalin was similar to that of ethanol in both tissues however it was significantly slower than methanol (N=4, P<0.005 in the heart; P<0.001 in the liver). The mean penetration coefficients of methanol, formalin and ethanol in the heart tissue were 2.609, 1.994 and 1.801, respectively, and 3.012, 2.153 and 2.113, respectively, in the liver tissue. The penetration coefficient of methanol was significantly greater than that of ethanol or formalin in both tissues (P<0.001 for each comparison). In conclusion, methanol penetrates tissue significantly faster than ethanol and formalin.
Description:
The rupture of an abdominal aortic aneurysm (AAA) causes about 200,000 deaths worldwide each year. However, there are currently no effective drug therapies to prevent AAA formation or, when present, to decrease progression and rupture, highlighting an urgent need for more research in this field. Increased vascular inflammation and enhanced apoptosis of vascular smooth muscle cells (VSMCs) are implicated in AAA formation. Here, we investigated whether hydralazine, which has anti-inflammatory and anti-apoptotic properties, inhibited AAA formation and pathological hallmarks. In cultured VSMCs, hydralazine (100
Description:
The rupture of an abdominal aortic aneurysm (AAA) causes about 200,000 deaths worldwide each year. However, there are currently no effective drug therapies to prevent AAA formation or, when present, to decrease progression and rupture, highlighting an urgent need for more research in this field. Increased vascular inflammation and enhanced apoptosis of vascular smooth muscle cells (VSMCs) are implicated in AAA formation. Here, we investigated whether hydralazine, which has anti-inflammatory and anti-apoptotic properties, inhibited AAA formation and pathological hallmarks. In cultured VSMCs, hydralazine (100
Description:
Objective: This study aimed to investigate the association of S1 hypertension, classified according to the 2017 American College of Cardiology/American Heart Association blood pressure (BP) guideline, with cardiovascular disease (CVD) mortality in adults with or without diabetes from the general United States population.Methods:This cohort study included 40 518 United States adults (including 3555 with diabetes) naive to antihypertensive drugs who attended the National Health and Nutrition Examination Surveys from 1988 to 2014.Results:Participants were followed up for 489 679 person-years (mean follow-up, 12.1 years) with 1569 CVD deaths being recorded. S1 hypertension was neither associated with an increased CVD mortality risk in the whole cohort nor in participants with or without diabetes after full adjustment. In age-stratified analyses, compared with normal BP, S1 hypertension was associated with increased CVD mortality in young adults, unrelated to CVD mortality in midlife, and associated with lower CVD mortality in the elderly. In older participants (
Description:
Objective: This study aimed to investigate the association of S1 hypertension, classified according to the 2017 American College of Cardiology/American Heart Association blood pressure (BP) guideline, with cardiovascular disease (CVD) mortality in adults with or without diabetes from the general United States population.Methods:This cohort study included 40 518 United States adults (including 3555 with diabetes) naive to antihypertensive drugs who attended the National Health and Nutrition Examination Surveys from 1988 to 2014.Results:Participants were followed up for 489 679 person-years (mean follow-up, 12.1 years) with 1569 CVD deaths being recorded. S1 hypertension was neither associated with an increased CVD mortality risk in the whole cohort nor in participants with or without diabetes after full adjustment. In age-stratified analyses, compared with normal BP, S1 hypertension was associated with increased CVD mortality in young adults, unrelated to CVD mortality in midlife, and associated with lower CVD mortality in the elderly. In older participants (
Description:
•Postabsorptive HOMA-IR was associated with CVD mortality.•Postabsorptive HOMA-IR was associated with diabetes mortality.•Postabsorptive HOMA-IR was associated with all-cause mortality. This study aimed to investigate associations of postabsorptive homeostasis model assessment for insulin resistance (HOMA-IR) with mortality. This cohort study included 13,927 US adults, among which 5,552 and 8,375 were examined at the postabsorptive and fasting state, respectively. Mortality outcomes were ascertained by linkage to the National Death Index records. The medians of postabsorptive and fasting HOMA-IR were 2.0 and 2.2, respectively. This cohort was followed up for 271,652 person-years with a mean follow-up of 19.5 years. During the follow-up, 5,235, 1,580, and 493 deaths from all causes, cardiovascular disease (CVD), and diabetes were recorded, respectively. A 1-natural-log-unit increase in postabsorptive HOMA-IR was associated with higher multivariate-adjusted risks for CVD mortality (HR, 1.30 95% CI, 1.12–1.50) and all-cause mortality (HR, 1.35 95% CI, 1.25–1.47). Similarly, a 1-natural-log-unit increase in fasting HOMA-IR was associated with higher multivariate-adjusted risks for CVD mortality (HR, 1.30 95% CI, 1.14–1.48) and all-cause mortality (HR, 1.27 95% CI, 1.19–1.36). Postabsorptive homeostasis model assessment for insulin resistance is a reliable biomarker for CVD mortality and all-cause mortality.