Supplementation with Co-enzyme Q10 (CoQ10) has been put to the test in horses, leading to increases in the important compound in skeletal muscle.
The compound is a component of the mitochondrial electron transport chain and plays an important role in aerobic cellular respiration.
In humans, chronic diseases, such as heart failure, hypertension and Parkinson’s disease, are characterised by low plasma CoQ10 concentrations and tissue CoQ10 content.
Supplementation with CoQ10, which is sold for humans as a dietary supplement, has been shown to improve clinical responses to treatment. Healthy human athletes have been found to develop CoQ10 deficiencies, believed to be due to increased metabolic demand.
It is also commonly taken by users of cholesterol-lowering statins who consider it eases a common side-effect of the drugs, muscle pain.
Deficiencies in skeletal muscle CoQ10 are thought to result in less efficient energy transduction due to decreased activity in the electron transport chain and suboptimal Adenosine triphosphate (ATP) production, resulting in reduced effective skeletal muscle contractile function and earlier onset of fatigue.
Professor Lisa Katz and her colleagues, writing in the Journal of Applied Animal Nutrition, say numerous studies have supported CoQ10 supplementation in human athletes to improve exercise capacity, aerobic power and recovery after exercise.
For their study, Katz and her fellow researchers set out to learn more about CoQ10 supplementation in horses.
The study involved 19 clinically healthy and privately owned Thoroughbreds from one farm who had never been in an exercise training programme. The horses comprised 11 intact males and eight females with an average age of 27.1 months.
Each horse acted as its own control, with jugular whole-blood and skeletal muscle biopsy samples taken before supplementation began. Samples were taken again, nine weeks after they had each received a daily oral dose of CoQ10, with food.
The dose was 1.5 milligrams per kilogram of body weight of a CoQ10-β-cyclodextrin inclusion complex in powdered form, containing 26% CoQ10 weight for weight.
The researchers reported that the horses accepted the supplementation with no adverse effects.
Plasma CoQ10 concentrations increased significantly in all horses after supplementation, by an average of 99%.
Concentrations of CoQ10 also increased significantly in the skeletal muscle of 16 of the horses, but in three of the horses, it actually fell a little below baseline values.
The fall seen in three horses potentially indicated an increased requirement for some horses to have higher plasma concentrations to facilitate the movement of CoQ10 into the skeletal muscle mitochondria, the researchers said.
They concluded that additional research is warranted to investigate training and exercise effects on skeletal muscle CoQ10 content in CoQ10 supplemented and un-supplemented Thoroughbreds
It is possible, according to the scientists from University College Dublin, Trinity College Dublin and Irish equine science company Plusvital, that increases in CoQ10 content in the skeletal muscle of horses may result in more efficient energy production.
Plusvital, following earlier research that found differences in CoQ10 activity in muscle from horses with a greater genetic propensity for aerobic exercise, developed a supplement for horses, EnerGene-Q10, which it says contains a highly bioavailable form of CoQ10.
The study was funded by Enterprise Ireland.
Prolonged oral coenzyme Q10-β-cyclodextrin supplementation increases skeletal muscle complex I+III activity in young Thoroughbreds
M.F. Rooney, C.E. Curley, J. Sweeney, M.E. Griffin, R.K. Porter, E.W. Hill and L.M. Katz.
Journal of Applied Animal Nutrition, https://doi.org/10.3920/JAAN2019.0001