Rats fed pea protein hydrolysate extracted from the yellow garden pea experienced a 20 per cent drop in blood pressure when compared to rats on a normal diet, scientists from the University of Manitoba told attendees at the American Chemical Society's 237th National Meeting.
"In people with high blood pressure, our protein could potentially delay or prevent the onset of kidney damage," said Rotimi Aluko, PhD. "In people who already have kidney disease, our protein may help them maintain normal blood pressure levels so they can live longer."
The study was performed in collaboration with Nutri-Pea Ltd., a private Canadian company, and funded by the Canadian government. Dr Aluki said that, if studies continue to show promise, the extract could hit the consumer market within the next two to three years.
Dr Aluko told NutraIngredients.com that the first market would be North America. “I expect that if the product is successfully established in North America, then it could be introduced into other markets very soon thereafter,” he said.
The extract could be made into a soluble powder that can be added to foods and beverages or it could be developed into a pill, added the scientists.
The study, which is yet to be published in a peer-review journal, involved feeding small daily doses of the protein to laboratory rats with polycystic kidney disease, a severe form of kidney disease used as a model for research on chronic kidney disease (CKD), a condition that has been affecting an increasing number of people in the US and elsewhere.
After eight weeks, Dr Aluko told attendees at the ACS meeting that the protein-fed rats with kidney disease showed a 20 per cent decrease in blood pressure when compared to diseased rats on a normal diet.
"This is significant because a majority of CKD patients actually die from cardiovascular complications that arise from the high blood pressure associated with kidney malfunction," noted Dr Aluko.
The researchers also report that consumption of the pea extract produced a 30 per cent increase in urine production in the diseased rats, bringing their urine to within normal levels.
Commenting on other studies in this area, Dr Aluko told this website: “There has been some work on in vitro effects of pea protein hydrolysate but ours is the first to demonstrate actual lowering of blood pressure in an animal model.”
The researchers are currently doing a clinical trial with mildly hypertensive human volunteers, with results expected in the autumn, he said.
“The rat model we used had both CKD and hypertension. Results from the current clinical trial will let us know whether the product works in hypertensive individuals,” he added.
The mechanism of action is not currently known, said the scientists, but proposed that the pea extract may boost production of cyclooxygenase-1 (COX-1), a protein that boosts kidney function.
Not any old pea
The new research focused on the yellow garden pea, but noted that consumption of the peas in their natural state would not produce the same potential health benefits as the purified protein extract. The potentially beneficial proteins exist in an inactive state in natural peas, and must be activated by treatment with special enzymes.
Furthermore, fears over flatulence would be unfounded since the purified proteins don't contain the complex plant-sugars found in fresh beans that are known to trigger flatulence. The extract itself does not appear to have any unpleasant taste or odour, he added.
“We have not published the results due to intellectual property issues,” said Dr Aluko. “However, we are nearing filing of a patent application and will submit the work for peer-review journal publication before the end of this year.”