Oxidative Stress, Genomic Integrity, and Liver Diseases

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

Excess reactive oxygen species production and free radical formation can lead to oxidative stress that can damage cells, tissues, and organs. Cellular oxidative stress is defined as the imbalance between ROS production and antioxidants. This imbalance can lead to malfunction or structure modification of major cellular molecules such as lipids, proteins, and DNAs. During oxidative stress conditions, DNA and protein structure modifications can lead to various diseases. Various antioxidant-specific gene expression and signal transduction pathways are activated during oxidative stress to maintain homeostasis and to protect organs from oxidative injury and damage. The liver is more vulnerable to oxidative conditions than other organs. Antioxidants, antioxidant-specific enzymes, and the regulation of the antioxidant responsive element (ARE) genes can act against chronic oxidative stress in the liver. ARE-mediated genes can act as the target site for averting/preventing liver diseases caused by oxidative stress. Identification of these ARE genes as markers will enable the early detection of liver diseases caused by oxidative conditions and help develop new therapeutic interventions. This literature review is focused on antioxidant-specific gene expression upon oxidative stress, the factors responsible for hepatic oxidative stress, liver response to redox signaling, oxidative stress and redox signaling in various liver diseases, and future aspects.

Related collections

Most cited references 186

Record: found
Abstract: found
Article: not found

ROS function in redox signaling and oxidative stress.

Michael Schieber, Navdeep S. Chandel (2014)

Oxidative stress refers to elevated intracellular levels of reactive oxygen species (ROS) that cause damage to lipids, proteins and DNA. Oxidative stress has been linked to a myriad of pathologies. However, elevated ROS also act as signaling molecules in the maintenance of physiological functions--a process termed redox biology. In this review we discuss the two faces of ROS--redox biology and oxidative stress--and their contribution to both physiological and pathological conditions. Redox biology involves a small increase in ROS levels that activates signaling pathways to initiate biological processes, while oxidative stress denotes high levels of ROS that result in damage to DNA, protein or lipids. Thus, the response to ROS displays hormesis, given that the opposite effect is observed at low levels compared with that seen at high levels. Here, we argue that redox biology, rather than oxidative stress, underlies physiological and pathological conditions. Copyright © 2014 Elsevier Ltd. All rights reserved.

0 comments Cited 1278 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Oxidative Stress and Antioxidant Defense

Esra Birben, Umit Murat Sahiner, Cansin Sackesen … (2012)

Abstract Reactive oxygen species (ROS) are produced by living organisms as a result of normal cellular metabolism and environmental factors, such as air pollutants or cigarette smoke. ROS are highly reactive molecules and can damage cell structures such as carbohydrates, nucleic acids, lipids, and proteins and alter their functions. The shift in the balance between oxidants and antioxidants in favor of oxidants is termed “oxidative stress.” Regulation of reducing and oxidizing (redox) state is critical for cell viability, activation, proliferation, and organ function. Aerobic organisms have integrated antioxidant systems, which include enzymatic and nonenzymatic antioxidants that are usually effective in blocking harmful effects of ROS. However, in pathological conditions, the antioxidant systems can be overwhelmed. Oxidative stress contributes to many pathological conditions and diseases, including cancer, neurological disorders, atherosclerosis, hypertension, ischemia/perfusion, diabetes, acute respiratory distress syndrome, idiopathic pulmonary fibrosis, chronic obstructive pulmonary disease, and asthma. In this review, we summarize the cellular oxidant and antioxidant systems and discuss the cellular effects and mechanisms of the oxidative stress.

0 comments Cited 748 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: not found

Mitochondrial formation of reactive oxygen species.

Julio Turrens (2003)

The reduction of oxygen to water proceeds via one electron at a time. In the mitochondrial respiratory chain, Complex IV (cytochrome oxidase) retains all partially reduced intermediates until full reduction is achieved. Other redox centres in the electron transport chain, however, may leak electrons to oxygen, partially reducing this molecule to superoxide anion (O2-*). Even though O2-* is not a strong oxidant, it is a precursor of most other reactive oxygen species, and it also becomes involved in the propagation of oxidative chain reactions. Despite the presence of various antioxidant defences, the mitochondrion appears to be the main intracellular source of these oxidants. This review describes the main mitochondrial sources of reactive species and the antioxidant defences that evolved to prevent oxidative damage in all the mitochondrial compartments. We also discuss various physiological and pathological scenarios resulting from an increased steady state concentration of mitochondrial oxidants.