Swallowing a pill isn’t always the best delivery method for some drugs — for instance, they may not survive the trip through the stomach’s acids, or they might be delivered all at once instead of gradually over time.
To circumvent those challenges, some scientists are aiming to genetically modify microbes that would take up residence in your intestines and churn out the drugs themselves.
Scientists have, for instance, modified gut microbes in mice to produce vitamin A and to stave off obesity.
And now, University of Florida researchers have genetically modified the gut microbe Lactobacillus paracasei to deliver a protein to treat high blood pressure.
In the study, one group of hypertensive mice got bacteria carrying the protein, another group got just the bacteria, and a third group received no treatment at all. After four weeks of twice-a-day treatment, the researchers found that mice getting the tweaked probiotic had reduced blood pressure, reduced heart wall thickness, and better heart contraction than either the untreated group or the group that received only bacteria.
Researchers presented their results, which haven’t yet been peer-reviewed, earlier this month at the American Heart Association Council on Hypertension meeting.
Probiotics have some important advantages over medications traditionally used to treat pulmonary hypertension — a type of high blood pressure affecting the lungs and heart — said lead researcher Mohan Raizada, professor of physiology at the University of Florida.
“It’s easier to make and easier to take,” he said. “One of the biggest problems in drug manufacturing is cost — of processing, of making sure it’s pure. But here, you just grow some bugs and you have it. And if this works, the probiotic could be given like yogurt. People could just eat it.”
Other ways of using the microbiome to treat disease are being tried. Fecal transplants, and their equivalent in pill form, are being used for some intractable infections such as Clostridium difficile. Probiotic pills and powders promise to re-seed the ecosystem of the intestines with “good bacteria,” though the evidence of whether they work is shaky. Other researchers are developing drugs that are targeted not at our own cells but at our microbes, to change the way they behave.
Still, genetically modified yogurt that lowers your blood pressure is a ways off.
“We’re not doing human studies because we have a lot more animal studies to do, focusing on other metabolic diseases, like diabetes,” said Raizada.
