Oxidative stress and epigenetic regulation in ageing and age-related diseases

Recent statistics indicate that the human population is ageing rapidly. Healthy, but also diseased, elderly people are increasing. This trend is particularly evident in Western countries, where healthier living conditions and better cures are available. To understand the process leading to age-associated alterations is, therefore, of the highest relevance for the development of new treatments for age-associated diseases, such as cancer, diabetes, Alzheimer and cardiovascular accidents. Mechanistically, it is well accepted that the accumulation of intracellular damage determined by reactive oxygen species (ROS) might orchestrate the progressive loss of control over biological homeostasis and the functional impairment typical of aged tissues. Here, we review how epigenetics takes part in the control of stress stimuli and the mechanisms of ageing physiology and physiopathology. Alteration of epigenetic enzyme activity, histone modifications and DNA-methylation is, in fact, typically associated with the ageing process. Specifically, ageing presents peculiar epigenetic markers that, taken altogether, form the still ill-defined “ageing epigenome”. The comprehension of mechanisms and pathways leading to epigenetic modifications associated with ageing may help the development of anti-ageing therapies

PROTECTIVE EFFECTS OF ANTHOCYANINS FROM BLACKBERRY IN A RAT MODEL OF ACUTE LUNG INFLAMMATION.

Anthocyanins are a group of naturally occuring phenolic compounds related to the coloring of plants, flowers and fruits. These pigments are important as quality indicators, as chemotaxonomic markers and for their antioxidant activities. Here, we have investigated the therapeutic efficacy of anthocyanins contained in blackberry extract (cyanidin-3-O-glucoside represents about 80% of the total anthocyanin contents) in an experimental model of lung inflammation induced by carrageenan in rats. Injection of carrageenan into the pleural cavity elicited an acute inflammatory response characterized by fluid accumulation which contained a large number of neutrophils as well as an infiltration of polymorphonuclear leukocytes in lung tissues and subsequent lipid peroxidation, and increased production of nitrite/nitrate (NOx) and prostaglandin E2 (PGE2). All parameters of inflammation were attenuated in a dose-dependent manner by anthocyanins (10, 30 mg kg-1 30 min before carrageenan). Furthermore, carrageenan induced an upregulation of the adhesion molecule ICAM-1, nitrotyrosine and poly (ADP-ribose) synthetase (PARS) as determined by immunohistochemical analysis of lung tissues. The degree of staining was lowered by anthocyanins treatment. Thus, the anthocyanins contained in the blackberry extract exert multiple protective effects in carrageenan-induced pleurisy

Свободнорадикальные механизмы повреждения при болезнях органов дыхания

Free radical mechanisms of injury in respiratory disease.Свободнорадикальные механизмы повреждения при болезнях органов дыхания

Carotenoids: Role in Neurodegenerative Diseases Remediation

Numerous factors can contribute to the development of neurodegenerative disorders (NDs), such as Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, Huntington’s disease, and multiple sclerosis. Oxidative stress (OS), a fairly common ND symptom, can be caused by more reactive oxygen species being made. In addition, the pathological state of NDs, which includes a high number of protein aggregates, could make chronic inflammation worse by activating microglia. Carotenoids, often known as “CTs”, are pigments that exist naturally and play a vital role in the prevention of several brain illnesses. CTs are organic pigments with major significance in ND prevention. More than 600 CTs have been discovered in nature, and they may be found in a wide variety of creatures. Different forms of CTs are responsible for the red, yellow, and orange pigments seen in many animals and plants. Because of their unique structure, CTs exhibit a wide range of bioactive effects, such as anti-inflammatory and antioxidant effects. The preventive effects of CTs have led researchers to find a strong correlation between CT levels in the body and the avoidance and treatment of several ailments, including NDs. To further understand the connection between OS, neuroinflammation, and NDs, a literature review has been compiled. In addition, we have focused on the anti-inflammatory and antioxidant properties of CTs for the treatment and management of NDs

Quantitative Proteomic Approaches for the Analysis of Human Lung Samples in Pulmonary Sarcoidosis

This thesis is focused on the analysis of protein expression profiles from the airways of sarcoidosis patients using quantitative proteomics. Sarcoidosis is a multisystemic inflammatory disorder of unknown etiology characterized by the presence of noncaseating granulomas in the affected organs. Previous findings in proteomics have reported identification of several proteins that certainly reflect the ongoing inflammation response but that did not have any specificity for sarcoidosis disease. The overall aim of these studies was therefore to continue searching for new protein candidates that could help us to determine the possible mechanisms behind sarcoidosis. We first investigated the total protein profile in the lung lumen from two granulomatous disorders, sarcoidosis (HLA-DRB1*15 positive), characterized to present an unresolved chronic inflammation disease and chronic beryllium disease (CBD) by collecting the bronchoalveolar soluble proteins and applying differential gel electrophoresis (DIGE) coupled to mass spectrometry (MS) (paper I). This led to the identification of fourteen proteins with altered profiles, some of these related to inflammation (β2-microglobulin, annexin II, complement C3, apolipoprotein A1, IgG kappa chain and heat shock protein 70) and the oxidative response (peroxiredoxin 5, hemopexin, α1-antitrypsin and superoxide dismutase), hence reflecting the persistent inflammation state in those granulomatous diseases. Gel-based 2DE techniques have been claimed to be unreliable in quantitative proteomics. The introduction of differential gel electrophoresis (DIGE) in 2DE approches has greatly improves gel-to-gel variation and the reproducibility; however, other sources of variance have been highlighted. In a 2D experimental-related study, we investigated the different sources of variance that were intrinsic to gel-based proteomics. We measured the technical variance related to background subtraction algorithms [4-8%] and the experimental variance related to the 1 st and 2 nd dimension of 2DE workflow (~30%). In addition, we reported the improvement of the 4 th generation image software program SameSpots TM in terms of reduced levels of variance introduced from background algorithms, higher levels of accurate spot-matching and most importantly an improved objectivity of the analysis (paper II). To further evaluate the protein changes in sarcoidosis we investigated the protein profiles from purified alveolar macrophages (AM). With the intention to improve both the protein resolution we applied two complementary proteomic approaches. First, all soluble AM proteins were resolved using the DIGE technique (paper III). Second all membrane-associated proteins (MAP) were then identified and quantified using the shotgun proteomic, liquid chromatography couple to mass spectrometry LC-MS/MS approach (paper IV). We found similar results from these parallel studies, including several pathways altered in sarcoidosis (papers III & IV). In addition, by applying multivariate regression analysis we could also identify a robust model with a set of 13 proteins able to discriminate sarcoidosis from the healthy group (paper IV). Taken together, improvements in gel-based image software and clinical sample pre-treatment allow more accurate and quantitative analysis, revealing deeper insight into the proteome. The biological findings presented in this thesis give new perspectives in understanding AM and their role in sarcoidosis disease as well as the possibility to search for disease biomarker

The Multifaceted Therapeutic Role of N-Acetylcysteine (NAC) in Disor-ders Characterized by Oxidative Stress

Oxidative stress, which results in the damage of diverse biological molecules, is a ubiquitous cellular process implicated in the etiology of many illnesses. The sulfhydryl-containing tripeptide glutathione (GSH), which is synthesized and maintained at high concentrations in all cells, is one of the mechanisms by which cells protect themselves from oxidative stress. N-acetylcysteine (NAC), a synthetic derivative of the endogenous amino acid L-cysteine and a precursor of GSH, has been used for several decades as a mucolytic and as an antidote to acetaminophen (paracetamol) poisoning. As a mucolytic, NAC breaks the disulfide bonds of heavily cross-linked mucins, thereby reducing mucus viscosity. In vitro, NAC has antifibrotic effects on lung fibroblasts. As an antidote to acetaminophen poisoning, NAC restores the hepatic GSH pool depleted in the drug detoxification process. More recently, improved knowledge of the mechanisms by which NAC acts has expanded its clinical applications. In particular, the discovery that NAC can modulate the homeostasis of glutamate has prompted studies of NAC in neuropsychiatric diseases characterized by impaired glutamate homeostasis. This narrative review provides an overview of the most relevant and recent evidence on the clinical application of NAC, with a focus on respiratory diseases, acetaminophen poisoning, disorders of the central nervous system (chronic neuropathic pain, depression, schizophrenia, bipolar disorder, and addiction), cardiovascular disease, contrast-induced nephropathy, and ophthalmology (retinitis pigmentosa). </jats:sec

Effect of posttranslational modification on the Na+, K+ ATPase kinetics

The Na+, K+ ATPase is an essential membrane protein in eukaryotic cells, which transports Na+ out of the cell in exchange for K+ into the cell. For this transport it hydrolyses one molecule of ATP for each cycle. The partial reactions of the ATPase cycle and the effects of posttranslational modifications on ATPase activity have been studied extensively. However, amalgamation of the reported rate constants for the partial reactions along with the effect of posttranslational modifications have never been attempted. We have designed a simplified four-state mathematical model of the Na+, K+ ATPase using published results for the partial reactions. We have incorporated the effect of the Na+ allosteric site and poise dependent glutathionylation and attempted to replicate K+ activated transient currents reported in voltage clamped cardiomyocytes. Our voltage clamped cardiomyocyte results indicate the K+ activated transient is an effect of poise dependent glutathionylation rather than the Na+ subsarcolemmal space. These results can be replicated to some extent by the proposed kinetic model. This is the first kinetic model of the Na+, K+ ATPase that incorporates both partial rate constants and a reported posttranslational modification which is able to reproduce voltage clamped cardiomyocyte data

Effect of posttranslational modification on the Na+, K+ ATPase kinetics

The Na+, K+ ATPase is an essential membrane protein in eukaryotic cells, which transports Na+ out of the cell in exchange for K+ into the cell. For this transport it hydrolyses one molecule of ATP for each cycle. The partial reactions of the ATPase cycle and the effects of posttranslational modifications on ATPase activity have been studied extensively. However, amalgamation of the reported rate constants for the partial reactions along with the effect of posttranslational modifications have never been attempted. We have designed a simplified four-state mathematical model of the Na+, K+ ATPase using published results for the partial reactions. We have incorporated the effect of the Na+ allosteric site and poise dependent glutathionylation and attempted to replicate K+ activated transient currents reported in voltage clamped cardiomyocytes. Our voltage clamped cardiomyocyte results indicate the K+ activated transient is an effect of poise dependent glutathionylation rather than the Na+ subsarcolemmal space. These results can be replicated to some extent by the proposed kinetic model. This is the first kinetic model of the Na+, K+ ATPase that incorporates both partial rate constants and a reported posttranslational modification which is able to reproduce voltage clamped cardiomyocyte data