MAR 05, 2020 12:24 PM PST

Researchers Learn How Gut Microbes Can Promote Heart Disease

WRITTEN BY: Carmen Leitch

The microbes in our gastrointestinal tract, collectively known as the gut microbiome, have a powerful impact on our health and well-being. Researchers are starting to learn more about the effect of specific strains of microbes, the genes they carry, and the molecules they produce and secrete. New work by scientists at the Cleveland Clinic has shown that phenylacetylglutamine (PAG), which is made by gut microbes, is connected to cardiovascular disease development, and heart attacks, strokes, and death it can cause. The findings have been reported in Cell.

Many foods contain an amino acid phenylalanine, including meat, beans, and soy. When microbes encounter phenylalanine in the gut, they break the compound down and in the process, generate a metabolite that ends up in the blood as PAG.

"Over the past decade there has been an increasing amount of data to suggest that gut microbes play a role in health, especially as it relates to heart disease," said Stanley Hazen, M.D., Ph.D., who holds multiple appointments including chair of the Department of Cardiovascular & Metabolic Sciences at Lerner Research Institute. "We found that blood levels of PAG contribute to cardiovascular disease risk in a couple of different ways."

In this work, the researchers assessed samples that were collected during a three-year period from over 5,000 patients. Elevated levels of PAG were found in patients that experienced strokes or heart attacks, and in type 2 diabetics. Diabetes is considered a risk factor for cardiovascular illness. When PAG was transplanted into animal models, the effects suggested that PAG can drive cardiovascular disease.

In an animal model of arterial injury, PAG was able to encourage the reactivity of platelets and boost clotting. That may be raising the likelihood that blood clots will form and lead to adverse cardiac events.
 
"Part of the reason we were so interested to have made this discovery is because we found that PAG binds to the same receptors as beta blockers, which are drugs commonly prescribed to help treat cardiac diseases." noted Hazen.

Cleveland Clinic researchers, led by Stanley Hazen, MD, PhD, have identified a gut microbe generated byproduct - phenylacetylglutamine (PAG) -that is linked to development of cardiovascular disease, including heart attack, stroke and death.  / Credit: Cleveland Clinic

When beta blockers were given to animals that had high levels of PAG, the negative cardiovascular effects were reduced. When gene editing was employed to stop PAG activity, clotting activity was significantly reduced.

"We believe our findings suggest that some of the benefits of beta blockers may be attributed to preventing PAG-related activity," said Hazen. "Beta blockers have been widely studied and are prescribed to many cardiac patients, but, to our knowledge, this is the first time that this mechanism has been suggested as an explanation for some of their benefits."

Sources: AAAS/Eurekalert! via Cleveland Clinic, Cell
 

About the Author
  • Experienced research scientist and technical expert with authorships on over 30 peer-reviewed publications, traveler to over 70 countries, published photographer and internationally-exhibited painter, volunteer trained in disaster-response, CPR and DV counseling.
You May Also Like
OCT 05, 2020
Plants & Animals
Bacteria Caused the Deaths of Hundreds of Elephants
OCT 05, 2020
Bacteria Caused the Deaths of Hundreds of Elephants
African elephants are a threatened species that are increasing in some areas but at risk in many others. There are proba ...
OCT 22, 2020
Microbiology
SARS-CoV-2 Has Multiple Routes Into Cells
OCT 22, 2020
SARS-CoV-2 Has Multiple Routes Into Cells
Since the pandemic virus SARS-CoV-2 emerged on the scene late last year, it's left a trail of devastation around the glo ...
NOV 05, 2020
Clinical & Molecular DX
Painless Microneedle Patch Diagnoses Malaria in Minutes
NOV 05, 2020
Painless Microneedle Patch Diagnoses Malaria in Minutes
It looks like a Band-Aid — a small, adhesive patch that is applied directly to the skin. This simple, low-cost dia ...
NOV 16, 2020
Microbiology
Using the Microbiome to Diagnose or Treat Autism
NOV 16, 2020
Using the Microbiome to Diagnose or Treat Autism
Autism is a complex disorder that has sent researchers searching for what is causing it, as the rates continue to rise. ...
DEC 08, 2020
Clinical & Molecular DX
"Honey, I Shrunk the PCR."
DEC 08, 2020
"Honey, I Shrunk the PCR."
In the 1530s, hundreds of years before microscopes and Petri dishes, an Italian physician called Girolamo Fracastoro wro ...
JAN 12, 2021
Microbiology
Connecting Gut Microbes, Diet, and Health
JAN 12, 2021
Connecting Gut Microbes, Diet, and Health
Advances in genetic technologies have revolutionized biomedical research in recent years. One example is the discovery t ...
Loading Comments...