The risk of heart disease is the focus of researchers. Scientists have discovered a lot about the various factors that contribute to heart disease, but there are also many factors unknown. Firstly, measuring inflammatory mediators and inflammatory levels in the body is a much better way of assessing cardiovascular risk and secondly known that proteins GlycA and CRP are found to be involved on inflammation, researcher conduct many studies. A recent study completed by experts from the Intermountain Medical Center Heart Institute in Salt Lake City discovered that two new biomarkers such as glycoprotein acetylation (GlycA) and C-reactive protein (CRP) both are associated with an increased risk of heart attack or stroke. Inflammation of the artery walls is a contributing factor to heart attack and stroke because it increases the likelihood that plaque on the arterial walls will rupture, induce clot formation and block blood flow.
Previous studied have shown GlycA as an indicator of chronic inflammation and a predictor of long-term risk of severe infection. Elevated GlycA corresponded to elevation of myriad inflammatory cytokines, as well as a gene co expression network indicative of increased neutrophil activity, suggesting that individuals with high GlycA may be in a state of chronic inflammatory response. Accordingly, analysis of infection-related hospitalization and death records showed that increased GlycA increased long-term risk of severe non-localized and respiratory infections, particularly septicaemia and pneumonia. In total, this study demonstrates that GlycA is a biomarker for chronic inflammation, neutrophil activity, and risk of future severe infection. 

C Reactive Protein (CRP) is produced by the liver and released from here in response to acute tissue damage and inflammation.  It is activated by macrophages and adipocytes in order to bind phosphocholine expressed on the surface of dead or dying cells in order to activate the C1Q complement part of the immune system.  This means that it helps drive up inflammatory activity in the body. CRP is one of the major inflammatory markers that should be measured when assessing inflammatory levels and risk of heart disease.

The study that led to the identification of GlycA and CRP started with a collection of plasma samples obtained by the Intermountain Heart Collaborative Study. The presence of high levels of GlycA, use identify by using a test developed by LipoScience known as NMR spectroscopy. Researchers measured lipoprotein particles and GlycA in 2,848 patients whose average age was 63 years old. Sixty-six percent of the patients were male and 65 percent had coronary artery disease. GlycA signals were quantified from signal amplitudes generated from the automated proton (H1) NMR LipoProfile test at the CLIA-certified LipoScience, Inc. (now LabCorp, Raleigh, NC) clinical laboratory. The GlycA signal is centered at 2.00±0.01 ppm in H1 NMR spectra of plasma, and only N‐acetylglucosamine with specific glycosidic linkage, that is, β (1→2) or β (1→6) with a preceding mannose residue, contributes to the GlycA signal. NMR signal amplitudes originating from the N-acetyl methyl group protons of the N-acetylglucosamine moieties located on the bi-, tri-, and tetra-antennary branches of specific serum proteins (mainly α1-acid glycoprotein, haptoglobin, α1-antitrypsin, α1-antichymotrypsin, and transferrin) were used to calculate the concentrations of GlycA expressed in μmol/L of N-acetyl methyl groups.

They found that GlycA could be a new marker of inflammation. But GlycA didn't predict coronary artery disease nearly as well. CRP is known to predict adverse heart events and coronary artery disease. Researchers are currently seeking to determine if C-reactive protein and GlycA are completely independent of each other in terms of their impact on inflammation and heart disease.

Using the results from the assay, researchers compared the value of GlycA and CRP in predicting heart attacks, stroke, and death. They also followed about three thousand patients undergoing coronary angiography, a procedure that identifies blood clots in the coronary arteries caused by plaque buildup from atherosclerosis..

 “The two proteins independently predicted future risk, and if you had both, it was the worst scenario completely,” explained lead author of the new study, J. Brent Muhlestein, MD.

These studies demostread that people with high levels of good cholesterol, or high-density lipoprotein, are not as safe from heart disease when high levels of a newly identified biomarker of inflammation in the arteries are also found in their bloodstream.

 

COPYRIGHT: This article is property of We Speak Science, a non profit institution co-fonded by Dr. Detina Zalli (Harvard University) and Dr. Argita Zalli (Imperial College London). The article is written by MSc. Gjena Dura (Molecular biologist, University of Tirana).

REFERENCES:

  • Intermountain Medical Center. "Elevated levels of inflammation marker offsets benefits of good cholesterol." ScienceDaily. ScienceDaily, 3 April 2016. <www.sciencedaily.com/releases/2016/04/160403152116.htm>.
  • Ridker PM, Hennekens CH, Buring JE, Rifai N. C-reactive protein and other markers of inflammation in the prediction of cardiovascular disease in women. N Engl J Med. 2000;342: 836–843. 
  • Otvos JD, Shalaurova I, Wolak-Dinsmore J, Connelly MA, Mackey RH, Stein JH, et al. GlycA: A Composite Nuclear Magnetic Resonance Biomarker of Systemic Inflammation. Clin Chem. 2015;61: 714–723. doi: 10.1373/clinchem.2014.232918
  • Akinkuolie AO, Buring JE, Ridker PM, Mora S. A novel protein glycan biomarker and future cardiovascular disease events. J Am Heart Assoc. 2014;3: e001221 doi: 10.1161/JAHA.114.001221
  • Ormseth MJ, Chung CP, Oeser AM, Connelly MA, Sokka T, Raggi P, et al. Utility of a novel inflammatory marker, GlycA, for assessment of rheumatoid arthritis disease activity and coronary atherosclerosis. 2015;17: 117. 
  • https://www.sciencedaily.com/releases/2016/04/160403152116.htm

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