New York, Nov 30 (IANS): Curcumin -- the active compound in turmeric -- may repair exercise intolerance faced by patients with heart failure, suggests a new research.

People with heart failure have a reduced function of the left ventricle -- the chamber of the heart that pumps blood out to the rest of the body -- called reduced ejection fraction. This is linked to decreased ability to exercise.

The findings showed that curcumin treatment improved muscle function, exercise capacity in mice with heart failure and healthy controls.

Curcumin, a chemical that comes from the turmeric plant, has been used as a traditional Asian medicine for centuries, primarily to treat gastrointestinal ailments and skin wounds.

Researchers from the University of Nebraska in the US, theorised that a reduction in the normal signalling of a protein Nrf2 may play a role in the impaired expression of antioxidant enzymes.

The antioxidant enzymes both prevent and repair damage from oxidative stress as well as improve exercise performance.

For the study, published in the Journal of Applied Physiology, the team gave one group of mice with heart failure daily doses of curcumin -- which is known to promote activation of Nrf2 -- for 12 weeks, while another group did not receive treatment.

The results showed that the expression of Nrf2 increased and levels of antioxidant enzymes improved in the animals with heart failure that were given curcumin.

In addition, both groups that received curcumin -- even the animals without heart failure -- had improved exercise capacity when compared with the untreated groups, suggesting the effects of curcumin on skeletal muscle is not exclusive to heart failure.

"These data suggest that activation of Nrf2 in skeletal muscle may represent a novel therapeutic strategy to improve ... quality of life" in people with heart failure with reduced ejection fraction, the researchers noted.