Media Releases

Turning back the clock on aging muscles?

February 18, 2014

New study supports the possibility of localized rejuvenation

TORONTO, ON – A study co-pub­lished in Nature Med­i­cine this week by Uni­ver­si­ty of Toron­to researcher Pen­ney Gilbert has deter­mined a stem cell-based method for restor­ing strength to dam­aged skele­tal mus­cles of the elder­ly.

Skele­tal mus­cles are some of the most impor­tant mus­cles in the body, sup­port­ing func­tions such as sit­ting, stand­ing, blink­ing and swal­low­ing. In aging indi­vid­u­als, the func­tion of these mus­cles sig­nif­i­cant­ly decreas­es.

“You lose fif­teen per­cent of mus­cle mass every sin­gle year after the age of 75, a trend that is irre­versible,” cites Gilbert, Assis­tant Pro­fes­sor at the Insti­tute of Bio­ma­te­ri­als & Bio­med­ical Engi­neer­ing (IBBME) and the Don­nel­ly Cen­tre for Cel­lu­lar & Bio­mol­e­c­u­lar Research (CCBR). The study orig­i­nates from Gilbert’s post­doc­tor­al research at Stan­ford University’s Bax­ter Lab­o­ra­to­ry for Stem Cell Biol­o­gy.

Through trac­ing the sig­nal­ing path­ways of the cells, the researchers – includ­ing lead author, Pro­fes­sor Helen Blau, and post­doc­tor­al researcher Ben Cos­grove – deter­mined that dur­ing aging, a sub­pop­u­la­tion of stem cells begin to express a mod­i­fi­ca­tion of a pro­tein that inhibits their abil­i­ty to grow and make new stem cells.

“But if we instead treat­ed those cells out­side the body with a drug that pre­vent­ed that pro­tein mod­i­fi­ca­tion from occur­ring, in com­bi­na­tion with cul­tur­ing the cells on some­thing soft that is rem­i­nis­cent of soft skele­tal tis­sue, like a hydro­gel bio­ma­te­r­i­al, the com­bi­na­tion allowed the aged cells to grow and make more copies of them­selves,” Gilbert describes.

The reju­ve­nat­ed cell cul­tures were then trans­plant­ed into injured and aged tis­sues, with remark­able results: the trans­plant­ed cells returned strength to the dam­aged and aged tis­sues to lev­els match­ing a young, healthy state. 

“We’ve now shown that mus­cle stem cells pro­gres­sive­ly lose their stem cell func­tion dur­ing aging,” Cos­grove said in a state­ment. “This treat­ment does not turn the clock back on dys­func­tion­al stem cells in the aged pop­u­la­tion. Rather, it stim­u­lates stem cells from old mus­cle tis­sues that are still func­tion­al to begin divid­ing and self-renew­ing.”

“An impor­tant thing to stress here is that this is not a panacea for aging in gen­er­al,” warns Dr. Blau. The stem cell treat­ment would only be used to repair local­ized defects in rel­a­tive­ly small mus­cles found in the hip area, the throat, or the mus­cles in the eye.

One of the sig­nif­i­cant chal­lenges to elder­ly indi­vid­u­als who receive hip trans­plants, for instance, is the chal­lenge of repair­ing skele­tal mus­cles around the hip joint injured dur­ing surgery. The study points to the poten­tial for future post-surgery ther­a­pies that could leave elder­ly hip replace­ment patients spry in a frac­tion of the time.

“Even a small, local­ized trans­plan­ta­tion could have a huge impact on qual­i­ty of life,” Blau said, adding, “One big advan­tage is that because the cells would come from the person’s own mus­cles there would be no prob­lem with an immune response.”

“It’s a real­ly new, excit­ing field,” says Gilbert, who argues that the mus­cle stem cell field, which only began to iso­late mus­cle stem cells for study with­in the last five years, is espe­cial­ly “wide open” in Toron­to where “there are real­ly impas­sioned clin­i­cian researchers who are inter­est­ed in restor­ing strength in aging and dis­ease.



The Insti­tute of Bio­ma­te­ri­als and Bio­med­ical Engi­neer­ing (IBBME) is a cut­ting-edge inter­dis­ci­pli­nary unit sit­u­at­ed between three Fac­ul­ties at the Uni­ver­si­ty of Toron­to: Applied Sci­ence & Engi­neer­ing, Den­tistry and Med­i­cine. The Insti­tute pur­sues research in four areas: neur­al, sen­so­ry sys­tems and reha­bil­i­ta­tion engi­neer­ing; bio­ma­te­ri­als, tis­sue engi­neer­ing and regen­er­a­tive med­i­cine; mol­e­c­u­lar imag­ing and bio­med­ical nan­otech­nol­o­gy; med­ical devices and clin­i­cal tech­nolo­gies.

Media con­tact:

Erin Vol­lick
Senior Com­mu­ni­ca­tions, Media & Alum­ni Rela­tions Offi­cer
Insti­tute of Bio­ma­te­ri­als and Bio­med­ical Engi­neer­ing (IBBME), Uni­ver­si­ty of Toron­toP: (416) 946‑8019  | E: | W: