A new study shows that gut bacteria have links to an abnormality in a brain blood vessel that can increase the chances of stroke.

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Researchers have examined the gut microbiome and found connections with a brain blood vessel abnormality.

New research has found a link between cavernous angiomas (CA), a type of brain blood vessel abnormality, and the gut microbiome’s composition.

The study further supports emerging research on the significance of the microbiota-gut-brain axis, which is the relationship between bacteria in the gut and how the brain functions.

According to one article, CA are a type of abnormal blood vessel in a person’s brain. Estimates show that 0.5% of the population has them. Of these, 40% become symptomatic, sometimes due to the vessel hemorrhaging.

Symptoms can include headaches, visual disturbances, seizures, or stroke.

Doctors can monitor CA with frequent magnetic resonance imaging (MRI) scans. Some people may require surgery.

Scientists know that CA have a genetic component, so a person may inherit certain gene variants that make developing CA more likely.

However, previous research on mice has shown that the gut microbiome may also affect CA. The microbiome is the collective genome of approximately 100 trillion micro-organisms, primarily bacteria, that live in a person’s gut.

While scientists have suggested a link between the gut microbiome and CA, more detail about what type of microbiome a person with CA has is not available, and few studies have looked at human subjects.

The authors of the present study, which is available in nature communications, wanted to determine what type of bacteria people with CA have, and whether different types of CA correlated to different gut microbiomes.

To do this research, the authors of the present study conducted an advanced genomic analysis of the stool samples of 122 people with at least one identified CA. They compared these samples to a control group matched for age and sex who did not have any CA.

The study found that the CA group had more gram-negative gut bacteria, whereas the control group had more gram-positive gut bacteria.

Further, the study found that particular types of gut bacteria were more prevalent in people with CA, even after they had accounted for possible confounding factors, such as sex, geographic location, or genetics.

The study also identified that the gut bacteria in the people with CA also produced more lipopolysaccharide molecules. The authors noted a link with the production of CA in mice.

As well as indicating a link between types of bacteria and the presence of CA, the study also demonstrated that the composition of some gut bacteria could help identify how aggressive CA might be.

Finally, the study made clear that analyzing the particular type of microbiomes in combination with blood plasma could help clinicians determine the severity of a person’s brain disorder.

The authors suggest that further research should involve larger cohorts and follow-up assessments. They also suggest that it may be valuable to look at the effects of diet on the microbiome and consequently, on CA.

While the research clarifies a link between the gut microbiome and CA, precisely how the two relate is not yet clear.

The microbiota-gut-brain axis is at the forefront of current health science research, and the relationship between the gut and the brain is complex.

However, the study provides further evidence for the importance of the gut-brain relationship and offers more detail on the specifics of CA in relation to gut bacteria.