Aging Heart Cells Offer Clues to Susceptibility of Older People to Severe COVID-19

A study published in the Journal of Molecular and Cellular Cardiology said genes that play a crucial role in allowing SARS-CoV-2 to invade heart cells become more active with age, which could help explain older people's susceptibility to severe COVID-19 infection, according to ScienceDaily . "As the pandemic has progressed, we've seen more and more COVID-19 patients — particularly older patients — affected by heart problems," said Professor Anthony Davenport at the University of Cambridge. "This suggests that the virus is capable of invading and damaging heart cells and that something changes as we age to make this possible." The investigators analyzed cardiomyocytes, which when damaged can affect the ability of the heart muscles to perform. The coronavirus must first penetrate the cardiomyocyte to cause damage, and the virus's spike protein binds to ACE2, a protein receptor on the surface of certain cells. The virus also can invade by compromising other proteins and enzymes, including TMPRSS2 and Cathepsins B and L. In comparing cardiomyocytes from five 19- to 25-year-old men and five men aged 63 to 78, the team found the genes that govern the generation of these proteins were significantly more active in cardiomyocytes from the older subjects — implying a likely increase in the corresponding proteins in aged cardiomyocytes. "The more we learn about the virus and its ability to hijack our cells, the better placed we are to block it, either with existing drugs or by developing new treatments," Davenport said.