Do Melatonin Levels Affect Pulmonary Arterial Hypertension? - Chromatography Investigates

Pulmonary hypertension is a severe disease. It is a relatively rare condition, but it is more common in people who have had a previous heart or lung condition. If it is allowed to progress without treatment it can lead to heart failure. There is currently no cure for pulmonary hypertension, and it can be difficult to get a correct diagnosis as its symptoms are like other heart and lung conditions.

With no cure, treatment involves delaying the disease’s progression. It has been shown in some animal models that exogenous melatonin might be beneficial for the treatment of pulmonary hypertension. A paper recently published in the Journal of Clinical Medicine has investigated the role of endogenous melatonin in patients with pulmonary hypertension and found that melatonin levels are linked to disease progression in patients with pulmonary hypertension.

What is pulmonary hypertension?

Pulmonary hypertension is high blood pressure in the blood vessels that supply blood to the lungs – the pulmonary arteries carry deoxygenated blood from the heart to the lungs to be oxygenated before delivery to the organs of the body. The walls of the pulmonary artery grow thick which means that they cannot expand to allow blood to flow through. The reduced blood flow means that the heart must work harder to pump blood to the lungs and then through the arteries to the other organs. As the heart must work harder it becomes weaker and this can lead to heart failure.

Pulmonary hypertension can be caused by changes in the pulmonary arteries including heart conditions, lung diseases or blood clots causing a narrowing or blockage in the pulmonary artery. Generally, treatments will first address underlying conditions to prevent the arteries from being permanently damaged. Then drugs can be used to prevent the blood from thickening or to widen the blood vessels.

Melatonin could affect pulmonary hypertension

Melatonin is a hormone that we synthesize in the pineal gland and helps us to regulate our circadian rhythm – when we wake and sleep. Studies have shown that melatonin exerts other benefits though, with studies suggesting links to protecting against cardiovascular disease and cancers amongst others. But although animal studies have shown that exogenous melatonin might be beneficial for patients with pulmonary hypertension, the clinical effect of endogenous melatonin levels are still unknown.

In the paper referenced above, researchers analysed the melatonin levels in patients with pulmonary hypertension and control patients to see if there was any clinical significance to the melatonin levels. Plasma levels of melatonin were measured using liquid chromatography and tandem mass spectrometry – an analytical technique discussed in the article, Analysis of Fenfluramine and Norfenfluramine in Mouse Brain and Cerebellum by Liquid Chromatography Tandem Mass Spectrometry using a Novel Solid-Supported Liquid Extraction. The group was followed for over three years and the study suggests lower melatonin levels are associated with a poorer longer-term survival for patients with some types of pulmonary hypertension.