The heart is a muscular organ that is about the size of a fist, located just behind, and slightly left of, the breastbone. The heart pumps blood through a network of arteries and veins, comprising the cardiovascular system. Image from http://easyhealthoptions.com/cardiovascular-system-working-overtime/
The heart has four chambers:
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The right atrium receives blood from the veins and pumps it to the right ventricle.
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The right ventricle receives blood from the right atrium and pumps it to the lungs, where it is loaded with oxygen.
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The left atrium receives oxygenated blood from the lungs and pumps it to the left ventricle.
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The left ventricle (the strongest chamber) pumps oxygen-rich blood to the rest of the body. The left ventricle’s vigorous contractions create our blood pressure.
Image from https://en.wikipedia.org/wiki/Heart
Because of the critical function of the heart, any heart disease can cause serious problems. In fact, heart disease has been the major cause of death in the world. The following figure shows the most fatal diseases by country:
Image from http://www.ibtimes.co.uk/new-global-illness-map-charts-countries-most-fatal-diseases-1453251
Myocardial infarction (heart attack) is a relatively common type of heart disease caused by blockage of the coronary artery, the artery which runs along the surface of the heart, and provides oxygen-rich blood to the heart muscle. Image from https://simple.wikipedia.org/wiki/Myocardial_infarction
Cardiac cells will die in a few minutes without blood supply, and unlike skin tissue, the heart can’t generate enough new cells to replace the dead ones. After a heart attack dead cells will be removed, which reduces mechanical support in the myocardial infarct region. In order to compensate for structural and functional changes in the damaged region, the heart will be remodeled to provide enough pressure for maintaining normal blood flow.
Multiple heart damage treatments are under investigation, such as stem cell therapy (R.R. Makkar et al., The Lancet, 2012), cardiomyocyte proliferation (K. Bersell et al., Cell, 2009), and biomaterial scaffolds (S.B. Seif-Naraghi et al., Tissue Engineering, 2014). However, none of them have thus far been accepted as reliable treatments for recovering damaged heart tissue effectively.
Image from E.R. Porrello. microRNAs in cardiac development and regeneration, Clinical Science(2013), 125.
Our lab is interested in extracellular matrix-induced cardiomyocyte proliferation. The growth factors and proteins in myocardial extracellular matrix can facilitate cardiac cell, especially cardiomyocyte, regeneration (C. Williams, et al., Acta Biomaterialia 2014). We expect that further investigation of the extracellular matrix can reveal cues of cardiomyocyte proliferation regulation and help us to develop effective methods for heart repair.Image from A.K. Gaharwar, et al., 3D Biomaterial Microarrays for Regenerative Medicine: Current State-of-the-Art, Emerging Directions and Future Trends, Advanced Materials, 2015.