Turn back the biological clock

A way to reverse ageing has been discovered, allowing withered muscle to rebuild itself, writes The Press Association.

The breakthrough could lead to new treatments that rejuvenate and strengthen ageing bodies or combat degenerative diseases, according to researchers from the University of Copenhagen’s Institute of Sports Medicine and Centre of Healthy Ageing and from the University of California.

Their findings, detailed in the European journal EMBO Molecular Medicine, underline the importance of staying active for older people, since this reduced age-related muscle loss.

Biochemical rejuvenation

»Our study shows that the ability of old human muscle to be maintained and repaired by muscle stem cells can be restored to youthful vigour given the right mix of biochemical signals,« says Professor Irina Conboy, from the University of California at Berkeley.

The effect has already been demonstrated on human muscle tissue in the laboratory.

Previously the same team had shown that molecular ‘messages’ from muscle cells alter with age to affect tissue repair.

Atrophy then exercise

The researchers compared muscle tissue samples from around 30 healthy men, surgically removing samples from the participants’ thighs.

The leg from which the biopsy was taken was immobilised in a cast for two weeks so that the muscles atrophied.

After the casts were removed, the men exercised with weights to rebuild their wasted muscles.

Old muscle recovers poorly

The scientists found that during the exercise period the muscles of younger volunteers had four times more regenerative stem cells engaged in tissue repair than those of older participants.

»The old muscle also didn’t recover as well with exercise,« says Morgan Carlson, UC Berkeley researcher and the study’s lead author, »this emphasizes the importance of older populations staying active because the evidence is that for their muscle, long periods of disuse may irrevocably worsen the stem cells’ regenerative environment.«

luci@adm.ku.dk