Researchers in Australia have demonstrated that a specially designed fermentable fiber can lower blood pressure in hypertensive patients. It has been shown to lower blood pressure in hypertensive patients as effectively as other drugs.
Physicians have long suggested dietary changes as the first option for treating high blood pressure in their patients. This intervention is known as DASH (diet to stop hypertension) and has proven to be very effective in lowering blood pressure in many patients.
However, there is still a lot of research being done on how DASH lowers blood pressure. The most common hypothesis is that diet produces beneficial changes in the gut microbiome, increasing production of short-chain fatty acids (SCFAs), which in turn improves blood pressure.
Francine Marques of the Monash University School of Biological Sciences has been investigating the relationship between these SCFA metabolites and blood pressure for several years. Previous preclinical studies have shown that acetate and butyrate, in particular, can lower blood pressure in animal models.
“These metabolites have untapped translational potential,” explains Marques. “In our previous study, we found that two microbial SCFAs, acetate and butyrate, lowered blood pressure in mice. and is not suitable for humans.”
As such, Marques and colleagues wondered if a type of artificial fiber could be deployed to help gut microbes provide consistently high levels of beneficial SCFAs. We turned to a fiber known as high-amylose corn starch, which can be modified to incorporate both butyrate and amylose. The final product is called HAMSAB (Acetylated and Butyrylated High Amylose Corn Starch).
When our gut microbes ferment HAMSAB, it releases large amounts of acetate and butyrate into the colon. The question this clinical trial sought to answer was whether HAMSAB supplementation in hypertensive patients could effectively lower blood pressure.
Twenty participants with untreated hypertension were recruited. For three weeks, the participant took her HAMSAB or placebo supplement daily. After a 3-week washout period, the placebo and HAMSAB groups switched supplements, so all 20 participants had tried both interventions by the end of the experiment.
“In hypertensive patients treated with HAMSAB, 24-hour systolic blood pressure decreased by 6.1 mmHg,” Dr. Marques announced. “This is the equivalent of a drug that lowers blood pressure and has important clinical implications.”
Blood tests revealed that HAMSAB supplementation significantly increased circulating levels of acetate and butyrate.
Additionally, the researchers confirmed that HAMSAB supplementation altered the composition of each patient’s gut microbiota, increasing levels of acetate- and butyrate-producing bacteria. According to Marques, the findings support a hypothesis that suggests that SCFAs produced by the microbiome play a role in regulating blood pressure in humans.
“This supports clinical and experimental findings that alterations in the gut microbiota, particularly depletion of SCFA-producing cells, may be a precursor to hypertension,” added Marques. “Therefore, fermentable fibers like HAMSAB may reconstitute SCFA-producing gut microbial communities.”
The new study is apparently based on only a small cohort of human subjects, so there is a lot of work to be done before something like this becomes clinically available.HAMSAB supplements will be the focus of future research. Although it is unclear whether or not, modulation of SCFA levels via the gut microbiome has been shown to effectively treat hypertension.
new research published Nature cardiovascular research.
Source: Monash University
