scholarly journals Toxicity of meta-Tyrosine

Plants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2800
Author(s):  
Marcin Tyminski ◽  
Katarzyna Ciacka ◽  
Pawel Staszek ◽  
Agnieszka Gniazdowska ◽  
Urszula Krasuska
Keyword(s):  
Oxidative Stress ◽  
Current Knowledge ◽  
Plant Competition ◽  
Harmful Effect ◽  
General Concept ◽  
Elevated Concentration ◽  
Chemical Weapon ◽  
Animal Cells ◽  
Cellular Redox ◽  
Living Organisms

L-Tyrosine (Tyr) is one of the twenty proteinogenic amino acids and also acts as a precursor for secondary metabolites. Tyr is prone to modifications, especially under conditions of cellular redox imbalance. The oxidation of Tyr precursor phenylalanine leads to the formation of Tyr non-proteinogenic isomers, including meta-Tyr (m-Tyr), a marker of oxidative stress. The aim of this review is to summarize the current knowledge on m-Tyr toxicity. The direct m-Tyr mode of action is linked to its incorporation into proteins, resulting in their improper conformation. Furthermore, m-Tyr produced by some plants as an allelochemical impacts the growth and development of neighboring organisms. In plants, the direct harmful effect of m-Tyr is due to its modification of the proteins structure, whereas its indirect action is linked to the disruption of reactive oxygen and nitrogen species metabolism. In humans, the elevated concentration of m-Tyr is characteristic of various diseases and ageing. Indeed, m-Tyr is believed to play an important role in cancer physiology. Thus, since, in animal cells, m-Tyr is formed directly in response to oxidative stress, whereas, in plants, m-Tyr is also synthesized enzymatically and serves as a chemical weapon in plant–plant competition, the general concept of m-Tyr role in living organisms should be specified.

scholarly journals Understanding Cellular Redox Homeostasis: A Challenge for Precision Medicine

2021 ◽  
Vol 23 (1) ◽  
pp. 106
Author(s):  
Verena Tretter ◽  
Beatrix Hochreiter ◽  
Marie Louise Zach ◽  
Katharina Krenn ◽  
Klaus Ulrich Klein
Keyword(s):  
Oxidative Stress ◽  
Precision Medicine ◽  
Redox Homeostasis ◽  
Reactive Species ◽  
Scientific Field ◽  
Redox Systems ◽  
Cellular Redox ◽  
Redox Biology ◽  
Living Organisms ◽  
Large Repertoire

Living organisms use a large repertoire of anabolic and catabolic reactions to maintain their physiological body functions, many of which include oxidation and reduction of substrates. The scientific field of redox biology tries to understand how redox homeostasis is regulated and maintained and which mechanisms are derailed in diverse pathological developments of diseases, where oxidative or reductive stress is an issue. The term “oxidative stress” is defined as an imbalance between the generation of oxidants and the local antioxidative defense. Key mediators of oxidative stress are reactive species derived from oxygen, nitrogen, and sulfur that are signal factors at physiological concentrations but can damage cellular macromolecules when they accumulate. However, therapeutical targeting of oxidative stress in disease has proven more difficult than previously expected. Major reasons for this are the very delicate cellular redox systems that differ in the subcellular compartments with regard to their concentrations and depending on the physiological or pathological status of cells and organelles (i.e., circadian rhythm, cell cycle, metabolic need, disease stadium). As reactive species are used as signaling molecules, non-targeted broad-spectrum antioxidants in many cases will fail their therapeutic aim. Precision medicine is called to remedy the situation.

scholarly journals The Tumorigenic Roles of the Cellular REDOX Regulatory Systems

2016 ◽  
Vol 2016 ◽  
pp. 1-17 ◽  
Author(s):  
Stéphanie Anaís Castaldo ◽  
Joana Raquel Freitas ◽  
Nadine Vasconcelos Conchinha ◽  
Patrícia Alexandra Madureira
Keyword(s):  
Oxidative Stress ◽  
Cancer Cell ◽  
Current Knowledge ◽  
Redox Homeostasis ◽  
Chemotherapeutic Agents ◽  
Antioxidant Systems ◽  
Cell Integrity ◽  
Cellular Redox ◽  
Regulatory Systems ◽  
Knowledge Of Cancer

The cellular REDOX regulatory systems play a central role in maintaining REDOX homeostasis that is crucial for cell integrity, survival, and proliferation. To date, a substantial amount of data has demonstrated that cancer cells typically undergo increasing oxidative stress as the tumor develops, upregulating these important antioxidant systems in order to survive, proliferate, and metastasize under these extreme oxidative stress conditions. Since a large number of chemotherapeutic agents currently used in the clinic rely on the induction of ROS overload or change of ROS quality to kill the tumor, the cancer cell REDOX adaptation represents a significant obstacle to conventional chemotherapy. In this review we will first examine the different factors that contribute to the enhanced oxidative stress generally observed within the tumor microenvironment. We will then make a comprehensive assessment of the current literature regarding the main antioxidant proteins and systems that have been shown to be positively associated with tumor progression and chemoresistance. Finally we will make an analysis of commonly used chemotherapeutic drugs that induce ROS. The current knowledge of cancer cell REDOX adaptation raises the issue of developing novel and more effective therapies for these tumors that are usually resistant to conventional ROS inducing chemotherapy.

Thiol redox control via thioredoxin and glutaredoxin systems

2005 ◽  
Vol 33 (6) ◽  
pp. 1375-1377 ◽  
Author(s):  
A. Holmgren ◽  
C. Johansson ◽  
C. Berndt ◽  
M.E. Lönn ◽  
C. Hudemann ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Reactive Oxygen Species ◽  
Main Part ◽  
Current Knowledge ◽  
Control Mechanisms ◽  
Oxygen Species ◽  
Redox Control ◽  
Cellular Redox ◽  
Thiol Redox ◽  
Induced Apoptosis

The Trx (thioredoxin) and Grx (glutaredoxin) systems control cellular redox potential, keeping a reducing thiol-rich intracellular state, which on generation of reactive oxygen species signals through thiol redox control mechanisms. Here, we give a brief overview of the human Trx and Grx systems. The main part focuses on our current knowledge about mitochondrial Grx2, which facilitates mitochondrial redox homoeostasis during oxidative stress-induced apoptosis.

scholarly journals MicroRNAs and Oxidative Stress: An Intriguing Crosstalk to Be Exploited in the Management of Type 2 Diabetes

Antioxidants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 802
Author(s):  
Teresa Vezza ◽  
Aranzazu M. de Marañón ◽  
Francisco Canet ◽  
Pedro Díaz-Pozo ◽  
Miguel Marti ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Type 2 Diabetes ◽  
Signaling Pathways ◽  
Current Knowledge ◽  
Critical Role ◽  
Cell Dysfunction ◽  
Non Coding Rnas ◽  
And Oxidative Stress ◽  
Molecular Crosstalk

Type 2 diabetes is a chronic disease widespread throughout the world, with significant human, social, and economic costs. Its multifactorial etiology leads to persistent hyperglycemia, impaired carbohydrate and fat metabolism, chronic inflammation, and defects in insulin secretion or insulin action, or both. Emerging evidence reveals that oxidative stress has a critical role in the development of type 2 diabetes. Overproduction of reactive oxygen species can promote an imbalance between the production and neutralization of antioxidant defence systems, thus favoring lipid accumulation, cellular stress, and the activation of cytosolic signaling pathways, and inducing β-cell dysfunction, insulin resistance, and tissue inflammation. Over the last few years, microRNAs (miRNAs) have attracted growing attention as important mediators of diverse aspects of oxidative stress. These small endogenous non-coding RNAs of 19–24 nucleotides act as negative regulators of gene expression, including the modulation of redox signaling pathways. The present review aims to provide an overview of the current knowledge concerning the molecular crosstalk that takes place between oxidative stress and microRNAs in the physiopathology of type 2 diabetes, with a special emphasis on its potential as a therapeutic target.

scholarly journals Molecular Mechanisms of Obesity-Linked Cardiac Dysfunction: An Up-Date on Current Knowledge

Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 629
Author(s):  
Jorge Gutiérrez-Cuevas ◽  
Ana Sandoval-Rodriguez ◽  
Alejandra Meza-Rios ◽  
Hugo Christian Monroy-Ramírez ◽  
Marina Galicia-Moreno ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Cardiac Dysfunction ◽  
Molecular Mechanisms ◽  
Current Knowledge ◽  
Peroxisome Proliferator ◽  
White Adipocyte ◽  
Peroxisome Proliferator Activated Receptors ◽  
And Oxidative Stress

Obesity is defined as excessive body fat accumulation, and worldwide obesity has nearly tripled since 1975. Excess of free fatty acids (FFAs) and triglycerides in obese individuals promote ectopic lipid accumulation in the liver, skeletal muscle tissue, and heart, among others, inducing insulin resistance, hypertension, metabolic syndrome, type 2 diabetes (T2D), atherosclerosis, and cardiovascular disease (CVD). These diseases are promoted by visceral white adipocyte tissue (WAT) dysfunction through an increase in pro-inflammatory adipokines, oxidative stress, activation of the renin-angiotensin-aldosterone system (RAAS), and adverse changes in the gut microbiome. In the heart, obesity and T2D induce changes in substrate utilization, tissue metabolism, oxidative stress, and inflammation, leading to myocardial fibrosis and ultimately cardiac dysfunction. Peroxisome proliferator-activated receptors (PPARs) are involved in the regulation of carbohydrate and lipid metabolism, also improve insulin sensitivity, triglyceride levels, inflammation, and oxidative stress. The purpose of this review is to provide an update on the molecular mechanisms involved in obesity-linked CVD pathophysiology, considering pro-inflammatory cytokines, adipokines, and hormones, as well as the role of oxidative stress, inflammation, and PPARs. In addition, cell lines and animal models, biomarkers, gut microbiota dysbiosis, epigenetic modifications, and current therapeutic treatments in CVD associated with obesity are outlined in this paper.

scholarly journals The Diverse Calpain Family in Trypanosomatidae: Functional Proteins Devoid of Proteolytic Activity?

Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 299
Author(s):  
Vítor Ennes-Vidal ◽  
Marta Helena Branquinha ◽  
André Luis Souza dos Santos ◽  
Claudia Masini d’Avila-Levy
Keyword(s):  
Proteolytic Activity ◽  
Current Knowledge ◽  
Current Therapy ◽  
Calcium Dependent ◽  
Administration Routes ◽  
Life Threatening ◽  
Living Organisms ◽  
Almost All ◽  
Open Question ◽  
Calpain Inhibitors

Calpains are calcium-dependent cysteine peptidases that were originally described in mammals and, thereafter, their homologues were identified in almost all known living organisms. The deregulated activity of these peptidases is associated with several pathologies and, consequently, huge efforts have been made to identify selective inhibitors. Trypanosomatids, responsible for life-threatening human diseases, possess a large and diverse family of calpain sequences in their genomes. Considering that the current therapy to treat trypanosomatid diseases is limited to a handful of drugs that suffer from unacceptable toxicity, tough administration routes, like parenteral, and increasing treatment failures, a repurposed approach with calpain inhibitors could be a shortcut to successful chemotherapy. However, there is a general lack of knowledge about calpain functions in these parasites and, currently, the proteolytic activity of these proteins is still an open question. Here, we highlight the current research and perspectives on trypanosomatid calpains, overview calpain description in these organisms, and explore the potential of targeting the calpain system as a therapeutic strategy. This review gathers the current knowledge about this fascinating family of peptidases as well as insights into the puzzle: are we unable to measure calpain activity in trypanosomatids, or are the functions of these proteins devoid of proteolytic activity in these parasites?

scholarly journals Protective Role of Nrf2 in Renal Disease

Antioxidants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 39
Author(s):  
Melania Guerrero-Hue ◽  
Sandra Rayego-Mateos ◽  
Cristina Vázquez-Carballo ◽  
Alejandra Palomino-Antolín ◽  
Cristina García-Caballero ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Current Knowledge ◽  
Unmet Need ◽  
Kidney Injury ◽  
Protective Role ◽  
Renal Diseases ◽  
Related Factor ◽  
Ckd Progression ◽  
Protective Mechanisms ◽  
Novel Therapeutic Strategies

Chronic kidney disease (CKD) is one of the fastest-growing causes of death and is predicted to become by 2040 the fifth global cause of death. CKD is characterized by increased oxidative stress and chronic inflammation. However, therapies to slow or prevent CKD progression remain an unmet need. Nrf2 (nuclear factor erythroid 2-related factor 2) is a transcription factor that plays a key role in protection against oxidative stress and regulation of the inflammatory response. Consequently, the use of compounds targeting Nrf2 has generated growing interest for nephrologists. Pre-clinical and clinical studies have demonstrated that Nrf2-inducing strategies prevent CKD progression and protect from acute kidney injury (AKI). In this article, we review current knowledge on the protective mechanisms mediated by Nrf2 against kidney injury, novel therapeutic strategies to induce Nrf2 activation, and the status of ongoing clinical trials targeting Nrf2 in renal diseases.

scholarly journals The Role of Oxidative Stress in NAFLD–NASH–HCC Transition—Focus on NADPH Oxidases

Biomedicines ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 687
Author(s):  
Daniela Gabbia ◽  
Luana Cannella ◽  
Sara De De Martin
Keyword(s):  
Oxidative Stress ◽  
Liver Disease ◽  
Fatty Liver ◽  
Fatty Liver Disease ◽  
Current Knowledge ◽  
Mechanisms Of Action ◽  
Nadph Oxidases ◽  
Alcoholic Fatty Liver ◽  
Alcoholic Fatty Liver Disease

A peculiar role for oxidative stress in non-alcoholic fatty liver disease (NAFLD) and its transition to the inflammatory complication non-alcoholic steatohepatitis (NASH), as well as in its threatening evolution to hepatocellular carcinoma (HCC), is supported by numerous experimental and clinical studies. NADPH oxidases (NOXs) are enzymes producing reactive oxygen species (ROS), whose abundance in liver cells is closely related to inflammation and immune responses. Here, we reviewed recent findings regarding this topic, focusing on the role of NOXs in the different stages of fatty liver disease and describing the current knowledge about their mechanisms of action. We conclude that, although there is a consensus that NOX-produced ROS are toxic in non-neoplastic conditions due to their role in the inflammatory vicious cycle sustaining the transition of NAFLD to NASH, their effect is controversial in the neoplastic transition towards HCC. In this regard, there are indications of a differential effect of NOX isoforms, since NOX1 and NOX2 play a detrimental role, whereas increased NOX4 expression appears to be correlated with better HCC prognosis in some studies. Further studies are needed to fully unravel the mechanisms of action of NOXs and their relationships with the signaling pathways modulating steatosis and liver cancer development.

scholarly journals Reactive Oxygen Species-Mediated Control of Mitochondrial Biogenesis

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Edgar D. Yoboue ◽  
Anne Devin
Keyword(s):  
Oxidative Stress ◽  
Mitochondrial Biogenesis ◽  
Redox State ◽  
Mitochondrial Genomes ◽  
Oxygen Species ◽  
Mitochondrial Content ◽  
Cellular Redox ◽  
High Importance ◽  
Complex Process ◽  
Long Time

Mitochondrial biogenesis is a complex process. It necessitates the contribution of both the nuclear and the mitochondrial genomes and therefore crosstalk between the nucleus and mitochondria. It is now well established that cellular mitochondrial content can vary according to a number of stimuli and physiological states in eukaryotes. The knowledge of the actors and signals regulating the mitochondrial biogenesis is thus of high importance. The cellular redox state has been considered for a long time as a key element in the regulation of various processes. In this paper, we report the involvement of the oxidative stress in the regulation of some actors of mitochondrial biogenesis.

scholarly journals Developmental Origins of Kidney Disease: Why Oxidative Stress Matters?

Antioxidants ◽  
2020 ◽  
Vol 10 (1) ◽  
pp. 33
Author(s):  
Chien-Ning Hsu ◽  
You-Lin Tain
Keyword(s):  
Oxidative Stress ◽  
Kidney Disease ◽  
Current Knowledge ◽  
Future Research ◽  
Antioxidant Systems ◽  
Developmental Origins ◽  
Adult Onset ◽  
Functional Changes ◽  
Health And Disease ◽  
Developing Kidney

The “developmental origins of health and disease” theory indicates that many adult-onset diseases can originate in the earliest stages of life. The developing kidney has emerged as being particularly vulnerable to adverse in utero conditions leading to morphological and functional changes, namely renal programming. Emerging evidence indicates oxidative stress, an imbalance between reactive oxygen/nitrogen species (ROS/RNS) and antioxidant systems, plays a pathogenetic role in the developmental programming of kidney disease. Conversely, perinatal use of antioxidants has been implemented to reverse programming processes and prevent adult-onset diseases. We have termed this reprogramming. The focus of this review is twofold: (1) To summarize the current knowledge on oxidative stress implicated in renal programming and kidney disease of developmental origins; and (2) to provide an overview of reprogramming effects of perinatal antioxidant therapy on renal programming and how this may prevent adult-onset kidney disease. Although early-life oxidative stress is implicated in mediating renal programming and adverse offspring renal outcomes, and animal models provide promising results to allow perinatal antioxidants applied as potential reprogramming interventions, it is still awaiting clinical translation. This presents exciting new challenges and areas for future research.

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