Tension might not be fun for us, but it looks like it’s critical for our hearts. So much so that without a little tension heart cells in the lab fail to develop normally.
This is a finding that took a mechanical engineer looking at a biological problem to solve. For many years now scientists have been able to mature stem cells into beating clumps of cells in the lab. But although those cells could beat, they didn’t do it very well. They don’t produce much force, can’t maintain a steady rhythm and would be a failure at pumping actual blood.
Beth Pruitt, PhD, a Stanford mechanical engineer, realized that in our bodies heart cells are under considerable tension, and thought that might be critical to how the cells develop.
She and postdoctoral scholar Alexandre Ribeiro started investigating how heart cells matured in different shapes and under different amounts of tension. They found a combination that produces normal looking cells with strong contractions.
The work could be useful for scientists hoping to replace animal heart cells as the gold standard for identifying heart-related side effects of drugs. Those cells are quite different from our own and often fail to detect side effects that could damage hearts in people taking the drug.
In my story about the work, I quote Ribeiro saying, “We hope this can be a drop-in replacement for animal cells, and potentially instead of having to do individual recordings from each cell we could use video analysis."
Previously: A new era for stem cells in cardiac medicine? A simple, effective way to generate patient-specific heart muscle cells and "Clinical trial in a dish" may make common medicines safer, say Stanford scientists
Photo by Alexandre Ribeiro