A newly developed virus that introduces a blood pressure-lowering gene into cells and enables that gene to maintain blood pressure at healthy levels for four months promises to take gene therapy for the disorder a step closer to reality, said researchers at Baylor College of Medicine in a report released online in the Proceedings of the National Academy of Sciences.
"High blood pressure is one of the leading causes of death and disability in adults worldwide," said Dr. Bert O'Malley, chair of the BCM department of molecular and cellular biology. "A therapy that could control blood pressure could have important benefits for individuals and for the health of the world's population as well."
The gene in question -- atrial natriuretic peptide or ANP -- promises to control blood pressure through a variety of effects on key areas involved in the problem of hypertension, including the relaxation of smooth muscle cells in blood vessels, increasing the vessels' diameters, and reducing the manner in which the vessels react to agents that can constrict those vessels. ANP also improves the manner in which the kidney eliminates sodium or salt from the body and inhibits other systems, such as the sympathetic nervous system, believed linked to development of high blood pressure.
"This makes ANP an attractive agent for use in treating blood pressure," said O'Malley. "However, its use is limited by the fact that it has such short-lived activity in the blood system."
Its activity is halved 30 seconds after it enters the blood stream.
Gene therapy can make cells generate more ANP. In previous studies, however, this kind of gene reduced blood pressure to dangerously low levels, said O'Malley. Obviously, a method of controlling the gene and the amount of ANP a cell makes was needed.