By AMERICAN HEART ASSOCIATION NEWS
ORLANDO, Florida — Modified probiotics taken orally may one day treat pulmonary hypertension, according to a study presented Thursday at the American Heart Association’s Council on Hypertension 2016 Scientific Sessions.
In the study, the probiotic Lactobacillus reduced blood pressure, improved heart contractility and reduced heart wall thickness in rats, researchers said.
“If the animal data holds true in clinical trials, probiotic consumption, as well as the use of genetically-modified probiotics, may emerge as a novel therapeutic approach for pulmonary hypertension therapy — either as standalone treatment or in conjunction with other medical therapies,” said Mohan Raizada, Ph.D., principal investigator of the study.
Pulmonary hypertension — high blood pressure in the lungs — makes the heart work harder to pump blood through the arteries of the lungs, which puts added strain on the heart. Risk factors for pulmonary hypertension include family history, congenital heart defects, cocaine use and chronic lung disease.
“It is known that the peptide Angiotensin-(1-7), or Ang-(1-7), is beneficial for the treatment of pulmonary hypertension in animal experiments,” said Colleen Cole Jeffrey, M.S., study author and graduate research assistant in the department of Physiology and Functional Genomics at the University of Florida in Gainesville. “But taking this peptide orally hasn’t been effective because it’s easily degraded in the stomach. To overcome this obstacle, we genetically engineered strains of Lactobacillus, a probiotic bacteria, to express and secrete Ang-(1-7).
Researchers measured the thickness of the rat heart wall, the ability of the heart to contract and the systolic blood pressure in the right side of the heart, which is a marker for pulmonary hypertension.
“All the animals with pulmonary hypertension had elevated blood pressure, increased heart wall thickness and decreased cardiac contractility compared to normal animals,” Cole Jeffrey said. “However, the group of pulmonary hypertensive animals that were fed with the Ang-(1-7) probiotic had a 43 percent reduction in blood pressure, a 33 percent reduction in heart wall thickness and a significant improvement in heart contractility, compared to the untreated animals with pulmonary hypertension.”