Researchers at the MRC Laboratory of Medical Sciences (LMS) have extended the lifespan of female fruit flies by boosting the levels of an enzyme which breaks down the reactive oxidant, hydrogen peroxide, inside cells. However, the anti-ageing effects were not due to the antioxidant activity of this enzyme, but because hydrogen peroxide is an important cell signalling molecule.
By Emily Armstrong
June 27, 2025
Time to read: 4 minutes
For a long time, scientists assumed that reactive oxidants were a cause of ageing, by triggering damage to the biological building blocks of our cells, such as DNA, proteins and lipids. Accumulation of this damage was ultimately held responsible for the deterioration of our bodies.
In recent years, a more nuanced understanding of reactive oxidants has emerged, with research revealing the essential role they play in cell biology, a process known as redox signalling. Reactive oxidants, particularly hydrogen peroxide, can transmit cellular messages, thereby controlling the function of proteins. Redox signalling occurs when hydrogen peroxide modifies a specific part of a protein, the amino acid called cysteine.
New research, published online in Nature Communications on 25 June 2025, highlights how redox signalling can affect survival by activating a process called autophagy, our internal biological recycling system that turns cellular ‘waste’ into useful nutrients and building blocks.
Dr Helena Cochemé, who led the work and heads the Redox Metabolism group at the LMS, explains: “Autophagy is recognised as an important longevity assurance mechanism, by helping to clear damage within our cells. From previous work in the ageing field, we know that promoting autophagy can extend lifespan and improve healthspan in a range of animal models. The novelty of our latest study comes from the redox regulation of autophagy in a living organism regulating survival.”
Dr Claudia Lennicke, a postdoctoral researcher in the Redox Metabolism group and first author of the paper, adds: “I find it fascinating how a single cysteine in a protein has such a profound impact on cellular function and physiological outcomes. When a cysteine becomes oxidised, this reaction acts as a molecular switch, which can change the function or activity of a target protein. This is precisely what we found in our study: by manipulating levels of the reactive oxidant hydrogen peroxide, we altered the activity of a protein involved in autophagy. These findings underline how redox modifications can fine-tune key cellular processes, and therefore influence organismal health and ageing.”
This project was a collaboration with Professor Dame Linda Partridge from the Institute of Healthy Ageing at UCL, and former Director of the Max Planck Institute for Biology of Ageing in Cologne, Germany. Linda says: “The fruit fly Drosophila is a valuable model system to help us study ageing. Flies have a shorter lifespan – months compared to years – so we can achieve scientific progress much more rapidly and efficiently. Many metabolic and signalling pathways are strongly conserved between flies and humans, so we can make exciting discoveries in Drosophila that are relevant for humans.”
Ageing is a critical area of research, since advancing age is a major risk factor for many diseases. Indeed, as humans are living longer, age-related diseases – such as cancer, diabetes, neurodegeneration and cardiovascular disorders – are on the rise.
Reflecting on the wider implications of these findings, Helena continues: “If we can understand the biological mechanisms underlying the ageing process itself and intervene, then we could potentially delay or even prevent multiple conditions from arising, therefore supporting humans to stay healthier for longer.”
Work in the Redox Metabolism group will continue to investigate how redox imbalances and disruptions to redox signalling contribute to ageing.
This study was primarily funded by the Medical Research Council and the Max Planck Society.
Read the full publication in Nature Communications: https://doi.org/10.1038/s41467-025-60603-w
About the image: The image at the top of the page is an artistic interpretation of the research. The oil painting by Claudia features a cysteine residue, which functions as a molecular switch in redox signalling. Surrounding the cysteine, digital auras represent membrane vesicles involved in autophagy, the biological process of cell ‘self-eating’. In this study, increasing autophagy by redox control promotes lifespan extension.