Redox signalling at a glance What it is: cells using small, controlled amounts of reactive oxygen and related molecules to pass messages The main messenger: hydrogen peroxide, working at very low concentrations How messages are read: reversible chemical changes to sulphur-containing cysteine sites on proteins A famous example: nitric oxide, whose signalling role in blood … Read more
The biology of ageing at a glance The framework: twelve hallmarks of ageing, set out by leading researchers in 2013 and updated in 2023 The common thread: damage builds up faster than cells can repair it, and the body’s responses gradually become part of the problem Genes versus life: recent large studies suggest genes explain … Read more
A circular RNA that lives inside mitochondria appears to act as a local stress sensor, ramping up antioxidant defences when cells detect oxidative damage. This discovery reveals how cells manage chemical threats at the precise location where they arise.
LL-37, a peptide produced by immune cells, acts as a redox sensor that coordinates cellular defence responses to oxidative stress. Researchers are discovering how this tiny messenger bridges immune defence and metabolic adaptation by responding differently to varying levels of reactive oxygen species.
Cells detect oxidative stress through a gene called KEAP1, which triggers production of proteins that prevent damaged proteins from clumping together. This surveillance system represents one of the cell’s most fundamental defence mechanisms.
Thioredoxin glutathione reductase is a specialised enzyme that recycles spent antioxidant molecules, allowing cells to defend against oxidative stress far more efficiently than if they had to synthesise new antioxidants constantly. Its structure encodes the ability to transfer electrons from NADPH to two separate antioxidant systems simultaneously.
When cells recover from low oxygen, hydrogen peroxide spikes and rewires their oxygen sensing pathways. This molecule acts not just as waste but as an active signal, helping cells transition between stress and recovery states.
When mitochondria fail to produce ATP, neurons lose the energy needed to run their antioxidant defence systems, triggering a cascade of oxidative damage. This mechanism appears central to understanding neurodegeneration.
NAC supports blood vessel function by boosting glutathione production, which protects nitric oxide from oxidative damage. This preservation helps maintain the endothelium’s ability to signal blood vessels to dilate properly.
Plant compounds from foods like berries and green tea directly interact with cellular repair enzymes after exercise, helping muscles recover faster. These phytochemicals work by modifying enzyme activity and triggering genetic pathways that boost antioxidant production during the critical recovery window.
The retina consumes more oxygen per gram than almost any tissue in the body, making it exquisitely sensitive to redox imbalance. When oxidative stress overwhelms antioxidant defences, retinal neurons begin dying in patterns seen in major eye diseases.
Thioredoxin is a small but powerful protein that acts like a cellular repair crew, fixing oxidised proteins and maintaining redox balance in every cell. This molecular battery can charge and discharge repeatedly, working with over 300 different proteins to keep cellular machinery running smoothly.