Study: Vitamin E supplementation may decrease muscle injury

A new study published​​ in the journal Nutrition ​suggests that vitamin E supplementation may be developed into an antioxidant therapy for dystrophinopathies, a common yet severe form of muscular weakness.

“The use of antioxidants as a therapeutic agent has recently gained renewed interest,” ​wrote the researchers from the State University of Campinas in Sao Paulo, Brazil. “Several studies have demonstrated positive outcomes regarding some diseases such as cardiovascular disease, atherosclerosis, allergic disease, neuromuscular disease, and muscular dystrophies.”​

They argued that, because vitamin E deficiency in human beings has been associated to muscle weakness, it is possible for the micronutrient to promote the reduction of oxidative stress and membrane repair in impaired muscles.

Study design​

Mice used in this study were specifically bred to mimic a muscular impairment condition in humans known as Duchenne muscular dystrophy. The mice were divided into two groups, one supplemented with 40 mg/kg daily vitamin E (from Nature Made), and the other, a control group, receiving only saline.

In this study, the vitamin E used represented eight fat-soluble compounds (four types of tocopherols and four types of tocotrienols) synthesized in plants.

Both mice received their supplementation by oral gavage for 14 days. At the end of the study, the animals were anaesthetized and blood samples taken for biochemical assessment of muscle fiber degeneration and inflammatory response.

Results and observations​

The vitamin E supplemented group had significantly reduced creatine kinase levels—an enzyme in which high levels indicate muscle fiber degeneration.

Membrane repair could be the mechanism involved in this vitamin E effect, according to the researchers, because of its lipid solubility. “Vitamin E partitions into the hydrophobic core of the plasma membrane bilayer, resulting in bilayer physical alterations such as fluidity, which increased at the bilayer surface of liposomes and decreased in the interior,” ​they wrote.

Another benefit may have come from vitamin E’s therapeutic effect on inflammation biomarkers, because it reduced the histologic and molecular inflammatory parameters.

Though previous similar studies conducted on human participants exhibited no improvement on antioxidant supplementation on muscle injury, the researchers argued that it did agree in conclusions of potential timing for such supplementation.

“Our research suggests that a vitamin E antioxidant strategy adapted to start before the muscular degeneration cycles begin may be a relevant therapeutic approach for DMD disease,”​ they wrote.

Source: ​Nutrition

Published online ahead of print, https://doi.org/10.1016/j.nut.2017.07.003​

Vitamin E treatment decreases muscle injury in mdx mice​

Authors:​ Rafael Dias Mancio, et al.