Hormone replacement therapy improves muscle function

This is a modelling of fiber and myonuclear domains (blue), as (A) an elliptical cylinder and (B) 3D representation of organization Credit: The Physiological Society, 2013

Hormone replacement therapy (HRT) significantly improves muscle function – down to the muscle fibre level – in postmenopausal women, a new study published today in The Journal of Physiology shows.

Some studies published over the last decade have led to negative publicity around HRT, a treatment used to relieve symptoms of menopause, resulting in many women being reluctant to use it. However this new study offers a positive outcome from the treatment.

Previous studies, monitoring and jumping height, have suggested that HRT reduces the impacts of age-related decline in muscle mass and strength. This new study is the first to explore these effects at cellular and molecular levels. The research team observed pairs of postmenopausal identical twins – of whom only one of each pair was receiving HRT – in order to rule out genetic differences, and then performed close examination of taken from them.

Dr Lars Larsson, from Uppsala University Hospital Sweden, who led the study, said:

"We found that even though individual muscle fibres did not change in size, the muscles of HRT users showed greater strength by generating a higher maximum force compared to non-HRT users. It is thought that using HRT, at least in part, reduces modifications of muscle contractile proteins that are linked to ageing."

HRT improves muscle function
This is a confocal microscopy showing myonuclei (blue) in an individual muscle fiber (red). Credit: The Physiological Society, 2013

"HRT is also associated with a more efficient organisation of myonuclei, which are essential components for muscle fibre function. In HRT users, the different myonuclei arrangement optimises cellular level that leads to improved ."

"Fall and fall-related injuries are common among elderly individuals, with significant socioeconomic consequences for individuals and society, and women are affected more than men due to the decrease in female sex hormone production."

"Future studies are focusing on the underlying the ageing-related changes in skeletal muscle and the specific effects of HRT on the structure and function of the dominant protein in skeletal muscle, called myosin, which generates force and movement."

These findings open up possibilities for future pharmacological interventions aimed at enhancing muscle mass and function in old age, and improving quality of life.

More information: Hormone replacement therapy improves contractile function and myonuclear organization of single muscle fibres from postmenopausal monozygotic female twin pairs. Rizwan Qaisar, Guillaume Renaud, Yvette Hedstrom, Eija Pöllänen, Paula Ronkainen, Jaakko Kaprio, Markku Alen, Sarianna Sipilä, Konstantin Artemenko, Jonas Bergquist, Vuokko Kovanen, and Lars Larsson. Journal of Physiology, May 1, 2013 591 (9) 2333-2344; doi:10.1113/jphysiol.2012.250092

add to favorites email to friend print save as pdf

Related Stories

HRT increases likelihood of hip and knee replacement

Oct 28, 2008

(PhysOrg.com) -- Having more children and using hormone replacement therapy (HRT) increases the likelihood that women will have joint replacement surgery, a large Oxford University-led study has shown.

Recommended for you

The impact of bacteria in our guts

13 hours ago

The word metabolism gets tossed around a lot, but it means much more than whether you can go back to the buffet for seconds without worrying about your waistline. In fact, metabolism is the set of biochemical ...

Stem cell therapies hold promise, but obstacles remain

14 hours ago

(Medical Xpress)—In an article appearing online today in the journal Science, a group of researchers, including University of Rochester neurologist Steve Goldman, M.D., Ph.D., review the potential and ch ...

New hope in fight against muscular dystrophy

15 hours ago

Research at Stockholm's KTH Royal Institute of Technology offers hope to those who suffer from Duchenne muscular dystrophy, an incurable, debilitating disease that cuts young lives short.

Biologists reprogram skin cells to mimic rare disease

Aug 21, 2014

Johns Hopkins stem cell biologists have found a way to reprogram a patient's skin cells into cells that mimic and display many biological features of a rare genetic disorder called familial dysautonomia. ...

User comments