Breakthrough could help sufferers of fatal lung disease

For the first time, scientists have identified a molecule which could pave way for new treatments that benefit patients suffering from the fatal lung disease Pulmonary Arterial Hypertension, a condition that affects the blood vessels in the lungs and leads to heart failure.
The ground breaking study has identified that replacing the microRNA molecule can not only stop but reverse the progression of the disease.
For the first time, scientists have identified microRNA molecule, that promotes the progression of the disease which affects 6,500 people in the UK, the University said in a statement today.
Allan Lawrie, from the University's Department of Infection, Immunity and Cardiovascular Disease, who led the research said: "This research opens up a new insight into regulation of gene signalling and PAH. It opens up a much needed new avenue for drug development to treat this condition".

Pulmonary Arterial Hypertension (PAH) is a chronic and debilitating condition that affects the blood vessels in the lungs and leads to heart failure. The devastating disorder, which causes sufferers to be breathless and tired, often affects young people in their 30s' and 40's and is more common in women.
The disease is caused by a sustained construction and a progressive narrowing of small arteries within the lung due to abnormal cell growth called vascular remodelling.

This remodelling causes an elevation in blood pressure within the lungs which places significant strain on the right side of the heart. The strain of the pressure causes fatal right ventricle failure. Current treatments for PAH target the constriction of the arteries but fail to fully reverse the vascular remodelling caused by the condition.

The new study, funded by the Medical Research Council (MRC), identified a specific small Ribonucleic acid (RNA) molecule that is downregulated in the blood of PAH patients - meaning the quality of a cellular component decreases.
The microRNA normally supresses SMURF1, a molecule that degrades the Bone Morphogenetic Protein Receptor 2 (BMPR2) which belongs to a family of genes originally identified for its role in regulating the growth and differentiation of bone and cartilage.
The loss of function in the BMPR2 gene is found to affect 80 per cent of families and around 20 per cent of individuals with idiopathic or familial PAH -- but the mutations of the gene alone do not explain the disease development.

Now, the research team led by Lawrie, a British Heart Foundation Senior Research Fellow, have discovered that the loss of the microRNA promotes the progression of PAH, and the replacement of the microRNA stopped and reversed the progression of disease in experimental models.
The research was published todayin 'The Journal of Clinical Investigation'.