scholarly journals NAD(P)H oxidase-derived reactive oxygen species contribute to age-related impairments of endothelium-dependent dilation in rat soleus feed arteries

2011 ◽  
Vol 110 (5) ◽  
pp. 1171-1180 ◽  
Author(s):  
Daniel W. Trott ◽  
John W. Seawright ◽  
Meredith J. Luttrell ◽  
Christopher R. Woodman

We tested the hypothesis that age-related endothelial dysfunction in rat soleus muscle feed arteries (SFA) is mediated in part by NAD(P)H oxidase-derived reactive oxygen species (ROS). SFA from young (4 mo) and old (24 mo) Fischer 344 rats were isolated and cannulated for examination of vasodilator responses to flow and acetylcholine (ACh) in the absence or presence of a superoxide anion (O2−) scavenger (Tempol; 100 μM) or an NAD(P)H oxidase inhibitor (apocynin; 100 μM). In the absence of inhibitors, flow- and ACh-induced dilations were attenuated in SFA from old rats compared with young rats. Tempol and apocynin improved flow- and ACh-induced dilation in SFA from old rats. In SFA from young rats, Tempol and apocynin had no effect on flow-induced dilation, and apocynin attenuated ACh-induced dilation. To determine the role of hydrogen peroxide (H2O2), dilator responses were assessed in the absence and presence of catalase (100 U/ml) or PEG-catalase (200 U/ml). Neither H2O2 scavenger altered flow-induced dilation, whereas both H2O2 scavengers blunted ACh-induced dilation in SFA from young rats. In old SFA, catalase improved flow-induced dilation whereas PEG-catalase improved ACh-induced dilation. Compared with young SFA, in response to exogenous H2O2 and NADPH, old rats exhibited blunted dilation and constriction, respectively. Immunoblot analysis revealed that the NAD(P)H oxidase subunit gp91phox protein content was greater in old SFA compared with young. These results suggest that NAD(P)H oxidase-derived reactive oxygen species contribute to impaired endothelium-dependent dilation in old SFA.

1999 ◽  
Vol 45 (4, Part 2 of 2) ◽  
pp. 69A-69A
Author(s):  
Charles V Smith ◽  
Sanjiv Gupta ◽  
Richard S Husser ◽  
Robert S Geske ◽  
Stephen E Welty

2016 ◽  
Vol 371 (1700) ◽  
pp. 20150434 ◽  
Author(s):  
Michael J. Berridge

Vitamin D is a hormone that maintains healthy cells. It functions by regulating the low resting levels of cell signalling components such as Ca 2+ and reactive oxygen species (ROS). Its role in maintaining phenotypic stability of these signalling pathways depends on the ability of vitamin D to control the expression of those components that act to reduce the levels of both Ca 2+ and ROS. This regulatory role of vitamin D is supported by both Klotho and Nrf2. A decline in the vitamin D/Klotho/Nrf2 regulatory network may enhance the ageing process, and this is well illustrated by the age-related decline in cognition in rats that can be reversed by administering vitamin D. A deficiency in vitamin D has also been linked to two of the major diseases in man: heart disease and Alzheimer's disease (AD). In cardiac cells, this deficiency alters the Ca 2+ transients to activate the gene transcriptional events leading to cardiac hypertrophy and the failing heart. In the case of AD, it is argued that vitamin D deficiency results in the Ca 2+ landscape that initiates amyloid formation, which then elevates the resting level of Ca 2+ to drive the memory loss that progresses to neuronal cell death and dementia. This article is part of the themed issue ‘Evolution brings Ca 2+ and ATP together to control life and death’.


2011 ◽  
Vol 300 (6) ◽  
pp. H2035-H2043 ◽  
Author(s):  
Julie Favre ◽  
Ji Gao ◽  
An Di Zhang ◽  
Isabelle Remy-Jouet ◽  
Antoine Ouvrard-Pascaud ◽  
...  

The deleterious effects of aldosterone excess demonstrated in cardiovascular diseases might be linked in part to coronary vascular dysfunction. However, whether such vascular dysfunction is a cause or a consequence of the changes occurring in the cardiomyocytes is unclear. Moreover, the possible link between mineralocorticoid receptor (MR)-mediated effects on the cardiomyocyte and the coronary arteries is unknown. Thus we used a mouse model with conditional, cardiomyocyte-specific overexpression of human MR (hMR) and observed the effects on endothelial function in isolated coronary segments. hMR overexpression decreased the nitric oxide (NO)-mediated relaxing responses to acetylcholine in coronary arteries (but not in peripheral arteries), and this was prevented by a 1-mo treatment either with an MR antagonist, vitamin E/vitamin C, or a NADPH oxidase inhibitor. hMR overexpression did not affect coronary endothelial NO synthase content nor its level of phosphorylation on serine 1177, but increased cardiac levels of reactive oxygen species, cardiac NADPH oxidase (NOX) activity, and expression of the NOX subunit gp91phox, which was limited to endothelial cells. Thus an increase in hMR activation, restricted to cardiomyocytes, is sufficient to induce a severe coronary endothelial dysfunction. We suggest a new paracrine mechanism by which cardiomyocytes trigger a NOX-dependent, reactive oxygen species-mediated coronary endothelial dysfunction.


Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3003
Author(s):  
Yun Haeng Lee ◽  
Ji Yun Park ◽  
Haneur Lee ◽  
Eun Seon Song ◽  
Myeong Uk Kuk ◽  
...  

Mitochondria are one of organelles that undergo significant changes associated with senescence. An increase in mitochondrial size is observed in senescent cells, and this increase is ascribed to the accumulation of dysfunctional mitochondria that generate excessive reactive oxygen species (ROS). Such dysfunctional mitochondria are prime targets for ROS-induced damage, which leads to the deterioration of oxidative phosphorylation and increased dependence on glycolysis as an energy source. Based on findings indicating that senescent cells exhibit mitochondrial metabolic alterations, a strategy to induce mitochondrial metabolic reprogramming has been proposed to treat aging and age-related diseases. In this review, we discuss senescence-related mitochondrial changes and consequent mitochondrial metabolic alterations. We assess the significance of mitochondrial metabolic reprogramming for senescence regulation and propose the appropriate control of mitochondrial metabolism to ameliorate senescence. Learning how to regulate mitochondrial metabolism will provide knowledge for the control of aging and age-related pathologies. Further research focusing on mitochondrial metabolic reprogramming will be an important guide for the development of anti-aging therapies, and will provide novel strategies for anti-aging interventions.


Author(s):  
Farhan Rizvi ◽  
Claudia C. Preston ◽  
Larisa Emelyanova ◽  
Mohammed Yousufuddin ◽  
Maria Viqar ◽  
...  

Background Age‐related heart diseases are significant contributors to increased morbidity and mortality. Emerging evidence indicates that mitochondria within cardiomyocytes contribute to age‐related increased reactive oxygen species (ROS) generation that plays an essential role in aging‐associated cardiac diseases. Methods and Results The present study investigated differences between ROS production in cardiomyocytes isolated from adult (6 months) and aged (24 months) Fischer 344 rats, and in cardiac tissue of adult (18–65 years) and elderly (>65 years) patients with preserved cardiac function. Superoxide dismutase inhibitable ferricytochrome c reduction assay (1.32±0.63 versus 0.76±0.31 nMol/mg per minute; P =0.001) superoxide and H 2 O 2 production, measured as dichlorofluorescein diacetate fluorescence (1646±428 versus 699±329, P =0.04), were significantly higher in the aged versus adult cardiomyocytes. Similarity in age‐related alteration between rats and humans was identified in mitochondrial‐electron transport chain‐complex‐I‐associated increased oxidative‐stress by MitoSOX fluorescence (53.66±18.58 versus 22.81±12.60; P =0.03) and in 4‐HNE adduct levels (187.54±54.8 versus 47.83±16.7 ng/mg protein, P =0.0063), indicative of increased peroxidation in the elderly. These differences correlated with changes in functional enrichment of genes regulating ROS homeostasis pathways in aged human and rat hearts. Functional merged collective network and pathway enrichment analysis revealed common genes prioritized in human and rat aging‐associated networks that underlay enriched functional terms of mitochondrial complex I and common pathways in the aging human and rat heart. Conclusions Aging sensitizes mitochondrial and extramitochondrial mechanisms of ROS buildup within the heart. Network analysis of the transcriptome highlights the critical elements involved with aging‐related ROS homeostasis pathways common in rat and human hearts as targets.


2019 ◽  
Author(s):  
Jesse G. Meyer ◽  
Thelma Garcia ◽  
Birgit Schilling ◽  
Bradford W. Gibson ◽  
Deepak A. Lamba

AbstractAge-related macular degeneration (AMD) is the leading cause of blindness in developed countries, and is characterized by slow retinal degeneration linked to chronic oxidative stress in the retinal pigmented epithelium (RPE). The exact molecular mechanisms that lead to RPE death and dysfunction in response to chronic reactive oxygen species (ROS) are still unclear. In this work, human stem cell-derived RPE samples were treated with a low dose of paraquat (PQ) for 1 week or 3 weeks to induce chronic reactive oxygen species (ROS) stress. Cells were then harvested and both the intracellular and secreted RPE proteomes were quantified by mass spectrometry. Inside the RPE, chronic ROS caused concerted increase of glycolytic proteins but decreased mitochondrial proteins, as well as decreased extracellular matrix proteins and membrane proteins required for endocytosis. From the secreted proteins, we found that stressed RPE secrete over 1,000 detectable proteins, and the composition of the proteins secreted from RPE changes due to chronic ROS. Notably, secreted APOE is decreased 4-fold due to 3 weeks of chronic ROS stress, and urotensin-II, the strongest known vasoconstrictor, doubles. Further, secreted TGF-beta is increased, and its cognate signaler BMP1 decreased in the secretome. Together, these alterations of the RPE proteome and protein secretome paint a detailed molecular picture of the retinal stress response in space and time.


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