free radicals

Oxidative Stress

What is Oxidative Stress?

Unpaired electrons in an atom/molecule are known as Reactive Oxygen Species (ROS), or free radicals. ROS / free radicals are naturally produced in the cells of all aerobic organisms. Electrons prefer/need to be in pairs, unpaired electrons are highly reactive and therefore unstable. Free radicals cause damage as they scour tissues trying to find electrons to pair with.

Optimally, an organism maintains a balance between free radicals and the antioxidants that neutralize them. Oxidative stress occurs when the body’s antioxidant defence mechanisms are unable to neutralize enough free radicals, there are too many for the cell/tissue to cope with and it becomes overwhelmed. Oxygen free radicals cause harm to proteins, lipids, DNA and other molecules. The result is oxidative damage in cells, tissues and organs. Lushchak describes it thus: “Oxidative stress is a situation when steady-state ROS concentration is transiently or chronically enhanced, disturbing cellular metabolism and its regulation and damaging cellular constituents” [1]

What Causes Oxidative Stress?

Reactive Oxygen Species including hydrogen peroxide, superoxide and hydroxyl radicals are created during normal life processes such as cellular respiration, lipid synthesis, phagocytosis of foreign bodies, metabolism of metals etc. Any chemical, physical or microbial toxic agent could compromise the delicate balance between antioxidants and reactive oxygen species. We introduce free radicals to our body in our diet (especially fried foods), water, medications, tobacco smoke, alcohol, pesticides and via pollutants in the air. Oxidative stress often occurs when our immune system is activated by invasion of microorganisms, or xenobiotics appear, or when the body is subjected to radiation (e.g. UV).

How Organisms Protect the Integrity of Cells and Tissues

Internal defence mechanisms such as antioxidant compounds and oxygen radical scavenging enzyme systems work to neutralize ROS. Superoxide dismutase, catalase, glutathione and ascorbic acid are just a few of the antioxidant mechanisms within cells and tissues. The immune system cleverly uses reactive oxygen species to attack invading pathogens. Oxidative stress also assists in the regulation of intracellular signal transduction and in physiologic adaptation.

Result of Oxidative Stress Damage

Free radicals scavenging the body looking for electrons to pair with cause oxidative DNA damage, protein damage and lipid peroxidation. Free radical damage is the commonest factor in cytotoxicity and genotoxicity and has been seen to cause carcinogenesis. According to a paper published in the Journal of the Japan Medical Association (Vol. 124, No. 11, 2000, pages 1549–1553), they will bring about a physiologic adaptation phenomena and regulation of intracellular transduction.

The result of oxidative stress is a deterioration in cell function, it has been linked to diseases such as Alzheimer’s, Parkinson’s, cardiovascular disease, hypertension, diabetes mellitus, chronic fatigue syndrome, atherosclerosis, cancer and many others. This makes it such an exciting research area, the potential is great.

Why Research Oxidative Stress?

Oxidative stress has a role to play in many diseases, research is increasing exponentially. Measuring the presence and effects of biomarkers increases our understanding of many lifestyle diseases and how to treat them effectively. Alongside an understanding of genetic profiles, analysing levels of oxidative stress allows us to tackle the problems it causes. Yearly, thousands of researchers study ways to reduce oxidative stress and therefore protect against: cancer, Alzheimer’s disease, Parkinson’s disease, Huntington’s disease, atherosclerosis and many other diseases.

Biorbyt provide the research tools to help you analyse the presence of particular components, establish location and quantity of specific molecules, assess alterations in molecules caused by redox reactions, understand physiological changes and how oxidative stress affects signalling mechanisms. The reliability of your results is dependent upon the quality of the analytical methods and research tools. Biorbyt supply rigorously tested immunoassays, monoclonal and polyclonal antibodies, antibody conjugates, proteins and small molecule inhibitors, so you can depend on our products to produce accurate, robust results.

Featured Oxidative Stress Products

Catalog # Name Reactivity
orb67347 DNA and RNA Damage antibody -
orb55620 DNA Damage (8-OHdG) ELISA Kit -
orb67346 Nitrotyrosine antibody Canine, Human, Rat
orb55623 Nitrotyrosine ELISA Kit -
orb396586 4-Hydroxynonenal antibody All
orb55640 Rat Mn SOD protein Rat
orb152243 SOD1 antibody Human, Mouse, Rat
orb67509 HO-1 antibody Canine, Human, Mouse, Rat
orb55618 HO-1 ELISA Kit Human
orb536203 Cortisol ELISA Kit Fish
orb396748 Dityrosine antibody All


  1. Lushchak V.I. Free radicals, reactive oxygen species, oxidative stress and its classification. Chem. Biol. Interact. 2014;224C:164–175. doi: 10.1016/j.cbi.2014.10.016.