Longevity Protein rejuvenates muscles

One of the unpleasant manifestations of aging is the loss of muscle tissue's ability to recover from damage. Researchers at the University of Pittsburgh, working under the guidance of Associate Professor Fabrisia Ambrosio, have found that the so-called "longevity protein" Klotho is both the cause of this and a potential therapeutic target.The authors demonstrated that in young mice, the expression of Klotho in muscle progenitor cells increases sharply after damage to muscle tissue, whereas in older animals it remains stable. Based on this, they came to the conclusion that genetically modified mice with Klotho deficiency can be used as a model of age-related extinction of regenerative abilities of muscle tissue. Such animals are also characterized by pathological ultrastructure of mitochondria, a decrease in their energy, damage to mitochondrial DNA, as well as increased entry of cells into the phase of physiological aging.

Assuming that Klotho acts by disrupting mitochondrial function, the authors introduced SS-31, a drug targeting mitochondria, currently undergoing phase 3 clinical trials, to animals with a deficiency of this protein. As a result of therapy, more new muscle tissue was formed in animals in the area of injury than in control group mice injected with saline. At the same time, their muscle strength after recovery was comparable to the muscle strength of genetically normal mice. At the same time, the administration of SS-31 to normal animals had no effect on the recovery of muscle damage.

At the final stage of the experiment, the authors demonstrated that the systemic administration of the exogenous Klotho protein rejuvenates the bioenergetics of muscle progenitor cells for a certain time and stimulates the regeneration of muscle fibers of old animals.

In general, the data obtained by the authors indicate that the Klotho transcription factor plays an important role in the regulation of mitochondrial function of muscle progenitor cells, as well as in the ability of skeletal muscles to regenerate. From a clinical point of view, the results obtained can be used in the therapy of elderly people with muscle injuries, as well as those who have undergone surgical interventions that damage muscle tissue. The administration of Klotho to such patients at a certain point in time will stimulate regeneration and increase the effectiveness of recovery.

Article by A. Sahu et al. Age-related declines in alpha-Klotho drive progenitor cell mitochondrial dysfunction and impacted muscle regeneration is published in the journal Nature Communications.

Evgenia Ryabtseva, portal "Eternal Youth" http://vechnayamolodost.ru based on the materials of the University of Pittsburgh: 'Longevity Protein' Rejuvenates Muscle Healing in Old Mice.