Medical University of South Carolina researchers have uncovered mechanisms by which high levels of the hormone FGF23 reduces brain health. High levels of fibroblast growth factor 23 were associated with structural changes in the frontal lobes of the brain. High levels are thought to lead to vascular calcification seen in chronic kidney disease. The study shows that such a process may affect brains of those without chronic kidney disease with elevated cardiovascular risk factors, according to Leonardo Bonilha, M.D., Ph.D.
FGF23 is produced in the bone, and typically works in the kidneys and gut to regulate levels of calcium and phosphate within the body. Levels are thought to be increased with diets high in phosphates which are often found in foods with preservatives. In people with such diets or chronic kidney disease FGF23 may be the reason for calcification of the arteries that leads to stroke or heart attack.
To determine if cardiovascular risk factors combined with high FGF23 levels present in those without chronic kidney disease was an indicator of problems in the brain the team recruited 50 patients to conduct this study, half of which had elevated cardiovascular risks and half didn’t; and all had normal kidney function.
Magnetic resonance imaging was used to examine connectomes in participants brains to see how different regions were connected, allowing examination of white matter that is more vulnerable to the type of stress that can occur with calcified vessels as frontal lobes have a high density of white matter. Modularity was looked for to reveal how well brain regions were connected as those with abnormally high modularity have higher levels of disconnection which may indicate problems with mental health in those areas. It was found that subjects with high levels of FGF23 and cardiovascular risk factors also had high modularity; subjects without cardiovascular risk factors FGF23 levels were not associated with increased modularity. Meaning that FGF23 is associated with brain health problems in those who already have high blood pressure, diabetes, or high cholesterol and as a result FGF levels may lead to structural damage in parts of the brain that may increase risks for stroke or problem with stroke recovery.
Results may have found a potential disparity in stroke recovery via highlighting vulnerability in those with high levels of FGF23 which is an important step to lead to strategies to improve dietary habits and improved brain health. Next the researchers hope to determine whether lowering the levels in those with cardiovascular risk factors will lead to improved brain health and/or better outcomes following stroke.