The "exposome" concept - how environmental risk factors influence cardiovascular health

There is general consensus that environmental pollution and non-chemical stressors contribute to the in- cidence and prevalence of chronic noncommunicable disease (e.g. cardiovascular, metabolic and mental). Clinical and epidemiological studies support that air pollution and traffic noise are associated with a higher risk for cardiovascular disease and significantly contribute to overall mortality. In this respect, the "exposome" provides a comprehensive description of lifelong exposure history. A recent publication using an updated global exposure-mortality model found that the global all-cause mortality rate attributable to ambient air pollution by PM2.5 and O-3 was 8.79 (95% CI 7.11-10.41) million in 2015 - much higher than previously calculated. For Europe this corresponds to 790,000 premature deaths due to ambient air pollution. Various large scale studies and expert commissions have identified air pollution as the leading health risk factor in the physical environment, followed by water and soil pollution with heavy metals, pesticides, other chemicals and occupational exposures, however neglecting the non-chemical environmental health risk factors: mental stress, light exposure, climatic changes and traffic noise. Especially for traffic noise-related health effects there are numerous clinical and epidemiological studies reporting significant impact on cardiovascular disease. We here provide an in-depth review on the health effects of the external exposome, with emphasis on air pollution and traffic noise and to a lesser degree mental stress and other environmental pollutants. In addition, we summarize our previously published experimental research investigating effects of aircraft noise exposure in mice and provide mechanistic insights on how noise contributes to noncommunicable disease

Development of an Analytical Assay for Electrochemical Detection and Quantification of Protein-Bound 3-Nitrotyrosine in Biological Samples and Comparison with Classical, Antibody-Based Methods.

Reactive oxygen and nitrogen species (RONS) cause oxidative damage, which is associated with endothelial dysfunction and cardiovascular disease, but may also contribute to redox signaling. Therefore, their precise detection is important for the evaluation of disease mechanisms. Here, we compared three different methods for the detection of 3-nitrotyrosine (3-NT), a marker of nitro-oxidative stress, in biological samples. Nitrated proteins were generated by incubation with peroxynitrite or 3-morpholino sydnonimine (Sin-1) and subjected to total hydrolysis using pronase, a mixture of different proteases. The 3-NT was then separated by high performance liquid chromatography (HPLC) and quantified by electrochemical detection (ECD, CoulArray) and compared to classical methods, namely enzyme-linked immunosorbent assay (ELISA) and dot blot analysis using specific 3-NT antibodies. Calibration curves for authentic 3-NT (detection limit 10 nM) and a concentration-response pattern for 3-NT obtained from digested nitrated bovine serum albumin (BSA) were highly linear over a wide 3-NT concentration range. Also, ex vivo nitration of protein from heart, isolated mitochondria, and serum/plasma could be quantified using the HPLC/ECD method and was confirmed by LC-MS/MS. Of note, nitro-oxidative damage of mitochondria results in increased superoxide (O2•-) formation rates (measured by dihydroethidium-based HPLC assay), pointing to a self-amplification mechanism of oxidative stress. Based on our ex vivo data, the CoulArray quantification method for 3-NT seems to have some advantages regarding sensitivity and selectivity. Establishing a reliable automated HPLC assay for the routine quantification of 3-NT in biological samples of cell culture, of animal and human origin seems to be more sophisticated than expected

Jake Wells Enterprises and the Development of Urban Entertainments in the South, 1890-1925

This dissertation explores the development of commercial entertainments and film exhibition in the urban South around the turn of the last century through the growth and decline of Jake Wells Enterprises. A former professional baseball player, Wells invested in a wide variety of public amusements, with the core of his early business centered on establishing and organizing a string of vaudeville, popularly priced, and legitimate theaters throughout the largest cities in the region, a network he later transitioned to showing exclusively motion pictures. A thorough analysis of period newspapers, trade journals, and some business records covering Wells’ career provides much-needed evidence for film and cultural historians wishing to understand the genesis and evolution of public amusements in the region, and its negotiation of traditional social and cultural institutions. In the 1890s, Wells played and managed several professional baseball teams in the South. The sport educated players and spectators alike to both the values and creed of New South progress, and to rising tensions confronting the intersection of modern and traditional forms of culture. Using his experiences and contacts gained in baseball, Wells helped foster a culture of entrepreneurship and innovation required for the progress of media industries in the region, establishing social networks of knowledge and improving distribution flows of entertainment. The dissertation explores how race and the genteel emerged as regional characteristics most influential to the success of this conversion in many urban areas. Protestants and evangelical culture served as the bulkhead supporting opposition to new amusements. Wells’ expansion plans and violations of Sabbath day laws evoked a “spatial” battle between commercialism and religion where political, social, and cultural power drawn from place and identity were challenged and reconfigured. Another chapter explores the exhibition and reception of early Civil War films in the region. Wells and other exhibitors were influential in their production and circulation nationwide, and positioned cinema as an alternative shrine to commemorate the Lost Cause in many communities. The last chapter shows how Wells failed to meet local demands and consumer desires in competition with the rise of national chain theaters and Hollywood’s vertical integration

Oxidative stress and vascular function

Many drug-induced complications and diseases are known to be associated with or even based on a dysequilibrium between the formation of reactive oxygen or nitrogen species (RONS) and the expression/activity of antioxidant enzymes that catalyze the breakdown of these harmful reactive species. The “kindling radical” concept is based on the initial formation of RONS that in turn activate additional sources of RONS in certain pathological conditions. Recently, we and others have demonstrated such “cross-talk” between NADPH oxidases and mitochondria in the setting of nitroglycerin-induced nitrate tolerance, the aging process and angiotensin-II triggered arterial hypertension via redox pathways compromising the mitochondrial, ATP-sensitive potassium channel (mKATP), the mitochondrial permeability transition pore (mPTP), cSrc and protein kinases and the NADPH oxidase isoform Nox2 (and eventually Nox1). This review will focus on the uncoupling of endothelial nitric oxide synthase (eNOS) by initially formed “kindling radicals” (RONS) and on the different “redox switches” that are involved in the uncoupling process of eNOS. S-glutathionylation of the eNOS reductase domain, adverse phosphorylation of eNOS, and of course the oxidative depletion of tetrahydrobiopterin (BH4) will be highlighted as potential “redox switches” in eNOS. In addition, RONS-triggered increases in levels of asymmetric dimethylarginine (ADMA) and L-arginine depletion will be discussed as alternative reasons for dysfunctional eNOS. Finally, we present the clinical perspectives of eNOS uncoupling (and dysfunction) for the development and progression of cardiovascular disease and discuss the important prognostic value of the measurement of endothelial function (e.g. by flow-mediated dilation or forearm plethysmography) for patients with cardiovascular disease

New Therapeutic Implications of Endothelial Nitric Oxide Synthase (eNOS) Function/Dysfunction in Cardiovascular Disease

The Global Burden of Disease Study identified cardiovascular risk factors as leading causes of global deaths and life years lost. Endothelial dysfunction represents a pathomechanism that is associated with most of these risk factors and stressors, and represents an early (subclinical) marker/predictor of atherosclerosis. Oxidative stress is a trigger of endothelial dysfunction and it is a hall-mark of cardiovascular diseases and of the risk factors/stressors that are responsible for their initiation. Endothelial function is largely based on endothelial nitric oxide synthase (eNOS) function and activity. Likewise, oxidative stress can lead to the loss of eNOS activity or even “uncoupling” of the enzyme by adverse regulation of well-defined “redox switches” in eNOS itself or up-/down-stream signaling molecules. Of note, not only eNOS function and activity in the endothelium are essential for vascular integrity and homeostasis, but also eNOS in perivascular adipose tissue plays an important role for these processes. Accordingly, eNOS protein represents an attractive therapeutic target that, so far, was not pharmacologically exploited. With our present work, we want to provide an overview on recent advances and future therapeutic strategies that could be used to target eNOS activity and function in cardiovascular (and other) diseases, including life style changes and epigenetic modulations. We highlight the redox-regulatory mechanisms in eNOS function and up- and down-stream signaling pathways (e.g., tetrahydrobiopterin metabolism and soluble guanylyl cyclase/cGMP pathway) and their potential pharmacological exploitation

Comparison of Mitochondrial Superoxide Detection Ex Vivo/In Vivo by mitoSOX HPLC Method with Classical Assays in Three Different Animal Models of Oxidative Stress

Background: Reactive oxygen and nitrogen species (RONS such as H2O2, nitric oxide) are generated within the organism. Whereas physiological formation rates confer redox regulation of essential cellular functions and provide the basis for adaptive stress responses, their excessive formation contributes to impaired cellular function or even cell death, organ dysfunction and severe disease phenotypes of the entire organism. Therefore, quantification of RONS formation and knowledge of their tissue/cell/compartment-specific distribution is of great biological and clinical importance. Methods: Here, we used a high-performance/pressure liquid chromatography (HPLC) assay to quantify the superoxide-specific oxidation product of the mitochondria-targeted fluorescence dye triphenylphosphonium-linked hydroethidium (mitoSOX) in biochemical systems and three animal models with established oxidative stress. Type 1 diabetes (single injection of streptozotocin), hypertension (infusion of angiotensin-II for 7 days) and nitrate tolerance (infusion of nitroglycerin for 4 days) was induced in male Wistar rats. Results: The usefulness of mitoSOX/HPLC for quantification of mitochondrial superoxide was confirmed by xanthine oxidase activity as well as isolated stimulated rat heart mitochondria in the presence or absence of superoxide scavengers. Vascular function was assessed by isometric tension methodology and was impaired in the rat models of oxidative stress. Vascular dysfunction correlated with increased mitoSOX oxidation but also classical RONS detection assays as well as typical markers of oxidative stress. Conclusion: mitoSOX/HPLC represents a valid method for detection of mitochondrial superoxide formation in tissues of different animal disease models and correlates well with functional parameters and other markers of oxidative stress

Adverse cardiovascular effects of traffic noise with a focus on nighttime noise and the new WHO noise guidelines

Exposure to traffic noise is associated with stress and sleep disturbances. The World Health Organization (WHO) recently concluded that road traffic noise increases the risk for ischemic heart disease and potentially other cardiometabolic diseases, including stroke, obesity, and diabetes. The WHO report focused on whole-day noise exposure, but new epidemiological and translational field noise studies indicate that nighttime noise, in particular,is an important risk factor for cardiovascular disease (CVD) through increased levels of stress hormones and vascular oxidative stress, leading to endothelial dysfunction and subsequent development of various CVDs. Novel experimental studies found noise to be associated with oxidative stress-induced vascular and brain damage, mediated by activation of the NADPH oxidase, uncoupling of endothelial and neuronal nitric oxide synthase, and vascular/brain infiltration with inflammatory cells. Noise-induced pathophysiology was more pronounced in response to nighttime as compared with daytime noise. This review focuses on the consequences of nighttime noise

NOX2ko Mice Show Largely Increased Expression of a Mutated NOX2 mRNA Encoding an Inactive NOX2 Protein

Background: The superoxide-generating enzyme nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (NOX2 or gp91phox, the phagocytic isoform) was reported as a major source of oxidative stress in various human diseases. Genetic deletion is widely used to study the impact of NOX2-derived reactive oxygen species (ROS) on disease development and progression in various animal models. Here, we investigate why NOX2 knockout mice show no NOX2 activity but express NOX2 mRNA and protein. Methods and Results: Oxidative burst (NOX2-dependent formation of ROS) was measured by L-012-based chemiluminescence and was largely absent in whole blood of NOX2 knockout mice. Protein expression was still detectable in different tissues of the NOX2 knockout mice, at the expected and a slightly lower molecular weight (determined by Western blot). The NOX2 gene was even largely enhanced at its expressional level in NOX2 knockout mice. RNA sequencing revealed a modified NOX2 mRNA in the knockout mice that is obviously translated to a truncated inactive mutant enzyme. Conclusion: Although the commercial NOX2 knockout mice display no considerable enzymatic NOX2 activity, expression of the NOX2 gene (when using standard primers) and protein (when using antibodies binding to the carboxy-terminal end) can still be detected, which may lead to confusion among investigators