Rodent study once again spotlights role of arginase in hypertension

U. of Missouri's William Durante

A new project at the University of Missouri has added a fresh set of animal data to back up earlier studies that spotlighted the enzyme arginase as a likely trigger for hypertension.

Focusing on the link between arginase and hypertension caused by obesity, William Durante, a professor of medical pharmacology and physiology at the University of Missouri School of Medicine and lead author of the study, says that arginase depletes arginine in the arteries and blood. The body uses arginine to create nitric oxide which lowers blood pressure. Without it, blood vessels constrict and blood pressure shoots up.

In the animal study, Durante both added the amino acid L-arginine to diets and blocked the action of arginase in obese rodents. Both methods worked, but the use of arginine as a supplement has caused problems in the past. That led Durante to conclude that the best approach for treating obesity-related hypertension could be finding the right therapy to inhibit arginase.

This isn't the first time arginase has been linked to hypertension. Several studies have been carried out, including one in 2013 that linked arginase to hypertension in metabolic disease. Another rat study on arginase and hypertension dates back to 2010.

"Blocking arginase activity offers a more specific approach in treating hypertension, because you are directly targeting the underlying biochemical defect in obesity," Durante said. "L-arginine is a natural amino acid commonly found in red meat, poultry, fish and dairy products. It is also manufactured and used as a nutritional supplement or medication. However, a dietary approach using L-arginine may not be the best treatment option. Yes, arginine increases nitric oxide, but it also exerts other biological effects, and it can be converted by arginase to alternative compounds that counteract its benefits to the circulation."

- here's the release