Research on Tamoxifen for Muscle Paralysis Treatment

Overview of Myotubular Myopathy

Researchers from Geneva and Strasbourg have recently explored the potential of tamoxifen, a medication primarily used for breast cancer, as a treatment for myotubular myopathy. This genetic disorder leads to muscle paralysis from birth, with no known treatments available. Tragically, most infants affected by this condition do not survive beyond the age of two.

Properties of Tamoxifen

Tamoxifen has antioxidant and antifibrotic properties that can help protect muscle fibers. These characteristics, combined with previous studies on muscular dystrophy, prompted a team from the University of Geneva and the University of Strasbourg to investigate the effects of tamoxifen on myotubular myopathy. Their findings were published in the journal Nature Communications.

Study Findings

In their study, researchers administered different dosages of tamoxifen to mice diagnosed with myotubular myopathy. The results revealed a significant increase in life expectancy. Mice receiving the lowest dose of tamoxifen saw their average life expectancy double, while those on intermediate doses experienced a tripling of life span. Notably, mice given the highest dose lived an average of 290 days, which is up to six times longer than untreated counterparts.

Impact on Paralysis and Muscle Strength

Beyond extending life expectancy, tamoxifen also slowed the progression of paralysis and tripled the muscle strength of the treated mice. The research team hypothesizes that administering tamoxifen earlier could enhance its effectiveness in treating myotubular myopathy. In the study, the treatment began when the mice first exhibited signs of hindleg paralysis. However, initiating treatment before symptoms appear may prevent the onset of the disease. Supporting evidence for this approach comes from a study conducted with younger mice at Toronto’s Sick Kids Hospital.

Future Directions

The researchers are optimistic about the potential for clinical trials in humans in the coming years.

References

Gayi E et al. Tamoxifen prolongs survival and alleviates symptoms in mice with fatal X-linked myotubular myopathy. Nat Commun. 2018 Nov 19;9(1):4848. doi: 10.1038/s41467-018-07058-4.
Université de Genève. A molecule for fighting muscular paralysis. EurekAlert! https://www.eurekalert.org/pub_releases/2018-11/udg-amf111618.php

Written by Agustin Dominguez Iino, BSc.