Medical

Probiotics and antibiotics team up against deadly superbugs

Probiotics and antibiotics tea...
Probiotics and antibiotics have formed an uneasy alliance against superbugs
Probiotics and antibiotics have formed an uneasy alliance against superbugs
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Left, probiotics (red) wrapped in a protective bubble of alginate, and right, a close-up of one sphere with the good bacteria tagged green
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Left, probiotics (red) wrapped in a protective bubble of alginate, and right, a close-up of one sphere with the good bacteria tagged green
Probiotics and antibiotics have formed an uneasy alliance against superbugs
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Probiotics and antibiotics have formed an uneasy alliance against superbugs

We're currently locked in an arms race against bacteria, and the bugs are winning as they continue to evolve resistance to our best drugs. Luckily, we have some double agents in the war – probiotics, or "good" bacteria that help keep bad bugs at bay. And now, MIT researchers have found a way to combine probiotics and antibiotic drugs into an uneasy alliance that seems to work better than either treatment alone.

As important as antibiotics have been for medicine over the past century, relying too heavily on them is proving to be dangerous. Overuse is speeding up the natural evolution process to the point where even our last line of defense is beginning to fail, threatening to return us to "the dark ages of medicine" where routine procedures and illnesses become potentially deadly again.

Although new antibiotics and alternative treatments are in development, there are still ways to squeeze more use out of existing technology, like supercharging old antibiotics or combining "failed" ones. In this case, the MIT team took a commercially-available probiotic called Bio-K+ and combined it with a regularly-used antibiotic called tobramycin.

Each of these ingredients is effective against a different superbug. Bio-K+ contains three species of Lactobacillus bacteria, often found in yogurt, which is able to kill a particularly nasty bug called methicillin-resistant Staphylococcus aureus (MRSA). Researchers aren't sure exactly how the probiotic kills MRSA, but it might have something to do with the lactic acid, peptides or other proteins they produce.

Meanwhile, tobramycin was chosen because it's effective against Pseudomonas aeruginosa. These two bacteria species often occur together in wound infections, meaning applying either Bio-K+ or tobramycin alone isn't usually enough to clear out everything.

The problem, of course, is that the antibiotic would also kill the probiotic. To overcome that, the researchers encapsulated the Bio-K+ in a compound called alginate, which forms part of the biofilm that colonies of bacteria build to protect themselves. As a bonus, alginate is already often used in wound dressings.

Left, probiotics (red) wrapped in a protective bubble of alginate, and right, a close-up of one sphere with the good bacteria tagged green
Left, probiotics (red) wrapped in a protective bubble of alginate, and right, a close-up of one sphere with the good bacteria tagged green

To test the unlikely duo, the MIT team added the mix to a lab dish containing Pseudomonas and MRSA, and found that it completely eradicated all bacteria. When they didn't bother wrapping the Bio-K+ in alginate, the antibiotic killed the probiotic as expected, which in turn meant the MRSA survived the attack.

"When we just used one component, either antibiotics or probiotics, they couldn't eradicate all the pathogens," says Zhihao Li, lead author of the study. "That's something which can be very important in clinical settings where you have wounds with different bacteria, and antibiotics are not enough to kill all the bacteria."

The researchers say the next step is to test the combo in animals and humans. After that, the treatment could be put to work in bandages that can help fight these kinds of infections in wounds. Alginate and the probiotic are already FDA-approved for human use, so that's one less hurdle in the way.

The research was published in the journal Advanced Materials.

Source: MIT

3 comments
BrianK56
A good healthy microbiome system in our bodies should be enough to eradicate most any bacteria with adequate time. In fact the first line of defenses is putting any foreign invaders in check before they can multiply.
EZ
Maybe the "Dark Ages of Medicine" weren't so dark after all. I've been dealing with a skin infection for the past 11 years that I think is a MRSA infection. For years, I've tried to get help from mainstream fake medicine, to no avail. I eventually turned to herbal compounds and think I've found the solution or, at least some good progress toward killing the infection. I believe I got the infection from a 10 hour head wound incident(observational) in a local hospital. It's a long story but, at least, the Dark Age stuff seems to be working better than all the synthetic stuff they threw at me--for years.
ljaques
Perhaps if we didn't continue to ruin our microbiome with pesticides, insecticides, and unwholesome foods, we'd regenerate those lovely immune systems our great grandparents had.