Heart disease is the leading cause of death and disability in several countries such as Malaysia, where heart disease remains as the number one cause of death for almost a decade (2005 – 2014). Similarly, in Singapore, heart disease is accountable for 29.5% of deaths in the nation in 2016 – translating to one out of three deaths related to heart failure.

In conjunction with World Heart Day, we have compiled three new studies that aid in curbing the killer disease.

1. Length of telomere may be directly related to heart failure

Telomeres in heart cells of people with heart failure appear to be shorter. Photo credit: Penn Medicine
Telomeres in heart cells of people with heart failure appear to be shorter. Photo credit: Penn Medicine

People with heart failure have cardiomyocytes – cells that make up the heart muscle – with shorter telomeres, according to researchers from Penn Medicine and the University of Connecticut.

The research published in the Journal of the American Heart Association is the first to develop a method for measuring the length of telomeres using human heart tissues.

“We acquired heart tissue samples from patients receiving heart transplants and organ donors in order to evaluate telomere length," said Foteini Mourkioti, PhD, the lead researcher and an assistant professor of Orthopaedic Surgery and Cell and Developmental Biology, and co-director of the Musculoskeletal Regeneration Programme in the Penn Institute for Regenerative Medicine.

Using the samples provided, the team identified crucial information such as age, sex and heart function. The length of telomeres in patients with heart diseases and patients with healthy heart were then measured.

Regardless of age, patients with heart diseases showed shorter telomere lengths in comparison to healthy patients. Patients with the most severely deceased heart function also had the shortest telomeres. Cardiomyocytes were the only heart cells affected by the telomere length in disease samples, while telomeres in other cells remained the same.

Moving forward, the team hopes to carve pathways that target cardiomyocytes to help with disease tracking.

2. Tricking the heart into believing exercise is done

The far-right image shows how a cardiotrophin treatment repaired heart muscle after a heart attack in a rat model. The blue areas are scar tissue and the red sections are healthy heart muscle. Photo Credit: Cell Research
The far-right image shows how a cardiotrophin treatment repaired heart muscle after a heart attack in a rat model. The blue areas are scar tissue and the red sections are healthy heart muscle. Photo Credit: Cell Research

Researchers from The Ottawa Hospital, University of Ottawa have discovered a protein called cardiothropin 1 (CT1) that could promote healthy growth of the heart, directly causing it to pump more blood – just as exercise and pregnancy would do.

The team stated that this growth differs to the harmful enlargement of the heart that is due to heart failure. CT1 can also repair heart damage and improve blood flow, as shown in animal models of heart failure. "When part of the heart dies, the remaining muscles try to adapt by getting bigger, but this happens in a dysfunctional way and it doesn't actually help the heart pump more blood," said Dr Lynn Megeney, senior author of the study and a senior scientist at The Ottawa Hospital and professor at the University of Ottawa.

The team conducted a variety of studies in mice, rats and cells growing in the lab. Besides CT-1, the study also experimented on phenylephrine (PE), a substance known to cause harmful heart growth.

It was found that heart growth stops and returns to its original condition when CT-1 treatment stops however heart growth continues after PE treatment stops. CT-1 also showed to improve heart function in two animal models of heart failure - one caused by a heart attack and one caused by high blood pressure in the lungs.

The team has patents pending for the use of CT-1 to treat heart conditions and hope to trial this protein in patients before making the treatment become widely available to patients.

3. Living nanogels to mend a broken heart

The contents of the stem cell-containing nanogel. Photo credit: ACS Nano
The contents of the stem cell-containing nanogel. Photo credit: ACS Nano

A hydrogel encapsulating stem cells to help heal the muscular walls of the heart, has been developed by an international team of researchers from China, Australia and the US. The research aims to provide a method to repair damage from myocardial infarctions.

The team encapsulated stem cells in nanogels made from heat-sensitive poly(N-isopropylacrylamine-co-acrylic acid). The liquid material turns into a soft gel when at body temperature. The nanogel did not affect stem cell growth or function and the stem cells did not trigger an immune response – a common problem with previous researches.

The nanogels were then injected into mouse and pig hearts and increased stem cell retention and regeneration was observed when the stem cells were encapsulated in nanogels compared to when the stem cells were directly injected without the nanogel.

The muscular walls of mouse and pig hearts also displayed added strength, suggesting that the therapy also promoted recovery after myocardial infarction. The team hopes to try this therapy on patients in the near future. MIMS


Read more:
Heart problems cause one-third of deaths worldwide
The lesser-known factors of cardiovascular disease
"Singheart" molecule: Groundbreaking discovery by Singapore researchers brings hope for heart disease patients worldwide

Sources:
https://medicalxpress.com/news/2017-09-team-telomere-length-heart-failure.html
https://medicalxpress.com/news/2017-08-heart.html
https://www.asianscientist.com/2017/09/in-the-lab/nanogel-heart-attack-stem-cell/
http://www.myheart.org.sg/article/about-the-heart-and-heart-disease/statistics/singapore/75
https://www.dosm.gov.my/v1/index.php?r=column/cthemeByCat&cat=401&bul_id=eTY2NW00S3BLb1dldWJmVFNMW
mphQT09&menu_id=L0pheU43NWJwRWVSZklWdzQ4TlhUUT09