Author Interviews, Heart Disease, JACC / 10.04.2019
Collagen Biomarker Associated With Atrial Fibrillation and Heart Failure Risk
MedicalResearch.com Interview with:
Susana Ravassa PhD
Program of Cardiovascular Diseases, CIMA
University of Navarra, and IdiSNA
Navarra Institute for Health Research
Pamplona, Spain
MedicalResearch.com: What is the background for this study?
Response: Atrial fibrillation (AF) is an evolving epidemic responsible for substantial morbidity, mortality and health-care expenditure. In particular, when AF and heart failure (HF) occur in combination, clinical evolution is particularly poor. Left atrial (LA) myocardial interstitial fibrosis (MIF) is the main structural lesion in AF and considered as the main factor responsible for the perpetuation of this pathology. In addition, it is known that MIF is associated with a lower effectiveness of the treatment of AF by pulmonary vein isolation with catheter ablation. Therefore, the identification of biomarkers related to MIF, as an affordable and minimally invasive approach, is of great interest to detect patients at risk of AF, as well as to monitor their response to the LA ablation therapy.
We had previously demonstrated that the deleterious impact of MIF in the heart is due to alterations in both the quality (i.e., extent of cross-linking among collagen fibrils and type of collagen fibers that determine their rigidity and resistance to degradation [collagen cross-linking or CCL]) and the quantity (i.e., extent of collagen fibers that occupy the myocardial tissue [collagen deposition or CD]) of fibrotic tissue. We have shown that certain circulating biomarkers related to collagen type I metabolism are associated with CCL and CD. On the one hand, the serum carboxy-terminal propeptide of procollagen type I (PICP), released during the conversion of procollagen type I into fibril-forming mature collagen type I, is directly correlated with myocardial CD.
On the other hand, the ratio of serum carboxy-terminal telopeptide of collagen type I to serum matrix metalloproteinase-1 (serum CITP:MMP-1 ratio) is inversely correlated with myocardial CCL, as the higher is the cross-linking among collagen type I fibrils the lower will be the cleavage of CITP by MMP-1 during the process of degradation of the fiber. Interestingly, we have previously reported that the combination of these biomarkers identifies patients with heart failure presenting with a complex pattern of MIF characterized by both increased CCL and CD (CCL+CD+) showing a higher risk of adverse clinical evolution as compared with heart failure patients without this combination of biomarkers. As both increased CCL and CD have been found in the left atrial myocardium in patients with AF, we designed this investigation to explore whether the CCL+CD+ combination of biomarkers is associated with AF.



Dr. Zhong[/caption]
Victor Wenze Zhong, Ph.D.
Postdoctoral fellow
Department of Preventive Medicine
Feinberg School of Medicine
Northwestern University
Chicago, IL 60611
MedicalResearch.com: What is the background for this study?
Response: Dietary cholesterol is a common nutrient in human diet. Eggs, specially egg yolks, are the single richest source of dietary cholesterol among all commonly consumed foods. The associations between dietary cholesterol consumption and cardiovascular disease and mortality remain controversial despite decades of research. Eating less than 300 mg of dietary cholesterol per day was the guideline recommendation before 2015. However, the most recent 2015-2020 Dietary Guidelines for Americans no longer include a daily consumption limit for dietary cholesterol and recommend weekly egg consumption as part of the healthy US-style eating pattern. Whether these recommendations are appropriate have been intensely debated.

Joanne B. Newbury, PhD
ESRC Postdoctoral Fellow
King’s College London
Social, Genetic & Developmental Psychiatry Centre
Institute of Psychiatry, Psychology & Neuroscience
London, United Kingdom
MedicalResearch.com: What is the background for this study?
Response: Urban living is one of the most well-established risk factors for adult psychotic disorders such as schizophrenia. However, less is known about the role of the urban environment in subclinical psychotic experiences in childhood and adolescence, such as hearing voices and extreme paranoia. These early psychotic experiences are a developmental risk factor for adult psychotic disorders and a range of other serious mental health problems such as depression and anxiety.
It is therefore important that we understand what factors might contribute to the development of early psychotic experiences so that we might be able to intervene and prevent their onset and progression.
In a cohort of over 2000 UK-born children (The Environmental Risk Longitudinal Twin Study), we have previously shown that subclinical psychotic experiences are also around twice as common among children and teenagers raised in urban versus rural settings. We have also shown that this appears to be partly explained by social features in urban neighbourhoods such as higher crime levels and lower levels of social cohesion.
However, no studies have examined the potential link between air pollution and psychotic experiences. This is despite air pollution being a major health problem worldwide (particularly in cities), and despite emerging evidence linking air pollution to the brain.