Manipulating gut microbiota to lower heart disease risk deserves 'greater scientific focus': Review
A high-fat diet has been found to compromise intestinal integrity by causing gut dysbiosis, which in turn leads to the development of heart diseases via two risk factors: atherosclerosis and hypertension.
This is induced by "imbalances in host-microbial interaction", which can activate numerous pathways, resulting in increased heart disease risk.
The review stated that rather than treating cardiovascular disease symptoms, the "newly elucidated connections between dysbiosis and cardiovascular disease pathogenesis present novel opportunities for early intervention".
Among the treatments recommended to correct the dysbiotic gut microbial compositions that promote heart disease is the administration of prebiotics and probiotics to introduce and restore beneficial microbial populations to the gut.
Prebiotics are said to protect the arteries by selectively contributing to the growth of beneficial gut microbiota, thereby lowering heart disease risk.
Plant polyphenols from fruits and vegetables, for instance, have been found to possess prebiotic characteristics, reducing inflammation-induced cholesterol.
Inulin and oligofructose, for example, have been shown to stimulate bifidobacteria growth, which aids in maintaining intestinal barrier integrity.
The review added that "prebiotic administration of inulin-type fructans can promote the restoration of butyrate-producing populations and, in turn, the atheroprotective effects of butyrate".
Probiotics’ effects on dysbiosis are strain-specific; the bacterial bile-salt hydrolase (BSH) activity of lactobacilli, in particular, is said to be beneficial.
The review said: “In addition to possessing a plethora of atheroprotective effects, BSH also detoxifies bile salts to enhance intestinal survivability. This confers lactobacilli strains an advantage in colonising the human gut.”
Furthermore, their ability to lower circulating cholesterol allows them to inhibit the formation, progression and rupture of atherosclerotic plaque.
The researchers said that despite the mixed results of certain human clinical studies on the subject, high-quality RCTs have “highlighted promising strains that elicit lipid-lowering effects”.
The review said microbiota can help re-establish homeostatis, and that future studies should investigate how prebiotics can aid the survival of probiotics to develop efficient symbiotic treatments for dysbiosis-induced heart diseases.
It concluded: "Although therapeutics for metabolic diseases have often targeted the host as an isolated entity, the scientific community should place a greater focus on exploring the therapeutic potential of the microorganisms that reside in the gastrointestinal tract."
"Bridging the Gap between Gut Microbial Dysbiosis and Cardiovascular Diseases"
Authors: Kimberley Lau, et al.