Scientists from the University of Manchester have discovered a drug used to treat erectile dysfunction can slow or even reverse the progression of heart failure in sheep. The study, funded by the British Heart Foundation is a breakthrough in the treatment of the disease in which five-year survival rates are lower than most common cancers.
Similar to Viagra, the study of Tadalafil proves that the drug is biologically useful as a treatment for heart failure in sheep. Professor Andrew Trafford, however, who was the lead author, however, argued that the effect is likely also to be shown in humans.
As devastating as heart failure can be, it occurs when the heart is too weak to pump enough blood to meet the needs of the body. Also, it causes a build-up of fluid that backs up into the lungs which result in breathlessness as well as fluid retention causing swelling of different parts of the body. And several of the current treatments are ineffective.
Professor Trafford explained that this discovery is an essential advance in a devastating condition which causes misery for thousands of people across the UK and beyond. He claimed further that scientists had limited evidence from human trials and epidemiological studies that show Tadalafil can be useful in treating heart failure.
Explaining further, he said that this study offers further confirmation, adds mechanistic details and demonstrates that Tadalafil could now be a possible therapy for heart failure. It is entirely possible that some patients taking it for erectile dysfunction have also unwittingly enjoyed a protective effect of their heart.
The team used sheep as the physiology of their hearts is the same as that of human hearts. When the animals had heart failure by induction of pacemakers that was sufficiently advanced to need treatment, the scientists administered the drug. Within a short period, the progressive worsening of the heart failure stopped, and essentially the drug reversed the impacts of heart failure.
The inability of the heart to respond to adrenaline which is the biological cause of breathlessness was almost completely reversed. The sheep received a similar dose used to treat humans for erectile dysfunction.
Tadalafil blocks an enzyme called Phosphodiesterase 5 or PDE5S for short, which regulates how human tissue responds to hormones like adrenaline. The scientists discovered that in heart failure, the drug altered the signaling cascade, a series of chemical reactions in the body, to restore the heart's ability to respond to adrenaline.
Professor Metin Avkiran, Associate Medical Director at the British Heart Foundation, explained that Viagra-type drugs were initially developed as potential treatments for heart disease before they were found to have unexpected benefits in the treatment of erectile dysfunction. Full research is published in the journal Scientific Reports.
