Researchers discovered a blood pressure switch for certain cells that can transform their function to help control blood pressure.
These cells are smooth muscle cells, they line our arteries. Normally, smooth muscle cells help control blood pressure by contracting and relaxing. But they work in a different way when blood pressure levels decrease significantly and for long periods. The smooth muscle cells in the kidney, and some other kidney cell types, take on a whole new job. They start producing renin. It is a substance typically manufactured in specialized cells in the kidneys to help maintain blood pressure.
The blood pressure switch
The UVA researchers identified a crucial biological “switch” that controls the changeover from their regular function to production of renin. This explains the cells’ secret superpower.
“Discovering how the switch works will help us understand how our bodies control blood pressure,” said Dr. R. Ariel Gomez, MD, of UVA’s Child Health Research Center. “Knowing how vascular cells change their identity could help develop new medications to treat high blood pressure and vascular diseases.”
The UVA team identified several biological mechanisms involved in this transformation. The researchers identified nine genes. They play key roles in the three biological “pathways” that regulate renin production. These genes are responsible for causing smooth muscle cells to stop producing renin. They trigger the cells to resume when needed. Hence, these cells can stop producing renin naturally. However, they remain “poised” to jump back into action.
Further, the scientists discovered factors that trigger the genes to resume renin production. This “epigenetic” switch is the key to understanding how renin production is controlled.
“We expected to find the region in your genome where this gene is located to be inaccessible when renin is turned off, but it turns out this spot stays generally accessible in cells that are ready to be called into action when more renin is needed,” Smith said. “Ultimately, since renin is so critical for our own health, a better understanding of how our bodies control its production may prove foundational to how we treat hypertension and the long-term effects of common blood pressure medications on kidney function and disease.”
The study’s significance
The UVA researchers’ work provides a comprehensive map of renin regulation. The findings give important direction to future research. Targeting the renin-control processes may lead to new treatments for high blood pressure.
“Now we want to identify markers and potential targets to mitigate and hopefully control unwanted effects of chronic stimulation of the renin cells,” Sequeira-Lopez said. “It is crucial to understand the basic secrets of our cells to design more and more effective therapies with less or no adverse effects.”
Findings Published
The researchers have published their findings in the scientific journal Hypertension. The research team consisted of Smith, Robert Paxton, Silvia Medrano, Nathan C. Sheffield, Sequeira-Lopez and Gomez.
