A new study has found that oxytocin, nicknamed the “love hormone” and “love drug”, can literally help heal the human heart.

The study, published in Frontiers in Cell and Development Biology, tested zebrafish and human cells and discovered that the “love drug” may promote critical organ regeneration following a heart attack.

During a heart attack, specialized cells responsible for heart contractions (called cardiomyocytes) die off and cannot replenish themselves. However, a subset of cells in the outer layer of the heart can reprogram themselves and become stem-like cells.

They are called Epicardium-derived Progenitor Cells (EpiPCs) and they are vital because they can regenerate into different types of heart cells, including cardiomyocytes.

Human production of EpiPCs is normally inefficient for heart regeneration, so scientists turned to zebrafish to test the effects of oxytocin on EpiPCs.

Once the zebrafish heart was injured, the messenger RNA expression for oxytocin increased in the brain by 20-fold. The oxytocin then traveled to the outer layers of the zebrafish heart and bonded to the oxytocin receptor, which triggered local cells to develop into EpiPCs. These EpiPCs then entered the middle layer of the heart and became cardiomyocytes.

The research team went one step further and tested 15 neurohormones on human tissue in vitro. Of those, only oxytocin was found to stimulate the production of EpiPCs. The team also showed a correlation between the stimulation of EpiPCs and oxytocin to regulate the migration, growth, and differentiation of cells.

Next, the team will conduct pre-clinical trials in animals and clinical trials in humans. While the study does show that oxytocin can help heart cells regrow, it may be a while before humans feel the love.