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Antibiotics could extend your life by culling older cells that can no longer divide

Antibiotics may hold promise in extending your life – and not by ridding you of killer infections.

Researchers claim the drugs may cull older cells that have lost the ability to divide and are linked to age-related disorders.

The senescent cells are thought to be the root cause of diseases including cancer, heart disease and even dementia.

Salford University scientists made the discovery using azithromycin, which treats infections ranging from gonorrhoea to Lyme disease. 

The antibiotic azithromycin was found to ‘cull’ old cells that can no longer divide 

The study comes amid fears of antibiotic resistance, driven by the unnecessary doling out of the drugs, which has fueled once harmless bacteria to become superbugs.

The World Health Organization (WHO) has previously warned if nothing is done the world is heading for a ‘post-antibiotic’ era. 

The researchers, led by Professor Michael Lisanti, exposed both normal cells and ‘old’ ones from human skin and lung tissue to a DNA-damaging agent.

They then added the antibiotics azithromycin and roxithromycin to compare their ability to remove the older cells.

Results showed that a single low-dose of azithromycin killed 97 per cent of the old cell. And the healthy cells still thrived. 

‘We may have unearthed a very inexpensive and readily available method of eliminating ageing cells that are toxic to the body,’ Professor Lisanti said.

‘It was an astonishing result and one that got us thinking about the implications for treating or preventing a variety of ageing-associated diseases.


Antibiotics have been doled out unnecessarily by GPs and hospital staff for decades, fueling once harmless bacteria to become superbugs. 

The World Health Organization (WHO) has previously warned if nothing is done the world is heading for a ‘post-antibiotic’ era.

It claimed common infections, such as chlamydia, will become killers without immediate solutions to the growing crisis.

Bacteria can become drug resistant when people take incorrect doses of antibiotics or if they are given out unnecessarily. 

Chief medical officer Dame Sally Davies claimed in 2016 that the threat of antibiotic resistance is as severe as terrorism.

Figures estimate that superbugs will kill 10 million people each year by 2050, with patients succumbing to once harmless bugs.

Around 700,000 people already die yearly due to drug-resistant infections including tuberculosis (TB), HIV and malaria across the world. 

Concerns have repeatedly been raised that medicine will be taken back to the ‘dark ages’ if antibiotics are rendered ineffective in the coming years.

In addition to existing drugs becoming less effective, there have only been one or two new antibiotics developed in the last 30 years.

In September, the WHO warned antibiotics are ‘running out’ as a report found a ‘serious lack’ of new drugs in the development pipeline.

Without antibiotics, C-sections, cancer treatments and hip replacements will become incredibly ‘risky’, it was said at the time.

‘Azithromycin is a relatively mild antibiotic that has been proven to extend lifespan in cystic fibrosis patients by several years.

‘Originally, the thinking was azithromycin is killing harmful bacteria in cystic fibrosis patients – but our tests now shed a new light on what might be actually going on.

‘Our new interpretation is the antibiotic is probably eliminating the senescent cells that are normally associated with ageing.’ 

Senescent cells may drive inflammation, with CF being associated with chronic inflammation in lung tissue, which shortens a sufferer’s lifespan.

Azithromycin is thought to force old cells to ‘kill themselves’ and shut off their energy supply. 

The results, published in the journal Aging, further suggested roxithromycin killed 70 per cent of the senescent cells by working in the same way as azithromycin, but also targeted some of the healthy ones.

‘If we consider our results and then we also consider what results have been achieved in clinical trials with cystic fibrosis patients, we are probably looking at the same mechanism(s), whereby antibiotics are removing inflammatory senescent cells and boosting healthy ones,’ co-lead author Professor Federica Sotgia said.

‘Undoubtedly, our results have significant implications for potentially alleviating or reversing tissue dysfunction and slowing the development of many ageing-associated diseases.’ 

Inflammation caused by senescent cells may be associated with the onset of cancer, as well as the disease’s recurrence and spread, the researchers wrote.

Previous studies have shown azithromycin removes cells that cause lung inflammation in mice who have been exposed to radiation.

While roxithromycin – which treats tonsilitis and pneumonia – is associated with hair regrowth. This may involve removing nearby old cells.

Cells are thought to age due to the accumulation of so-called senescent cells.

These are older, deteriorated cells that do not function as well as they should and spread such effects to the cells that surround them. 

Cells are thought to become senescent due to DNA damage or inflammation, as well as an inability to turn genes on and off at the right time.