Postbiotics May Prevent Diabetes in Obesity

You’ve likely heard about probiotics—live bacteria with long, colorful names found in your yogurt that help generate a happy gut. You may have even heard of prebiotics, which are compounds that have a beneficial effect on the bacteria in your body. But you’re probably less familiar with postbiotics—factors derived from bacteria that can also have a positive impact on our health.

Researchers at McMaster University who study diabetes and obesity have discovered a postbiotic factor called MDP that prevents pre-diabetic obese mice from developing diabetes. Their surprising results were recently published in Cell Metabolism.

When bacteria in the gut become chronically out of balance—known as intestinal dysbiosis [PDF]—a person can become insulin resistant, or prediabetic. Dysbiosis is often found in people with obesity. “Key markers on the road to diabetes are insulin sensitivity and insulin resistance—how well that hormone can lower blood glucose,” Jon Schertzer, lead study author and assistant professor of biochemistry at McMaster University tells Mental Floss. Insulin’s job is to bring your blood glucose back up to normal after you eat or drink something. If you’re insulin resistant, or improperly sensitive, insulin can’t do its job properly. “What a postbiotic does is allow the insulin to do a better job,” he says.

Schertzer’s team sought to investigate whether postbiotics could have an impact on obesity before a person becomes overtly diabetic. “The focus of this study is prediabetes—the stage before the overt disease has developed and it’s still reversible. Obesity is the biggest risk factor for prediabetes,” he explains.

The team found that a postbiotic called muramyl dipeptide (MDP), derived from a bacterial cell wall, was able to reduce insulin resistance in mouse models—regardless of weight loss or changes in the intestinal microbiome during obesity.

To test this, Schertzer separated mice into two groups. One group was given MDP at the same time as they were fed a high-fat diet intended to cause obesity. In that experiment, the mice were given MDP four days per week for five weeks. The MDP injections improved insulin and glucose tolerance after five weeks—remarkably, without altering body mass or fatty tissue levels.

In the second group, the team fed the mice into a state of obesity over 10 weeks, putting them into a state of prediabetes. Then they injected MDP into the mice three times over three days and saw a rapid improvement in blood glucose by the third day. “It’s not that the injection itself is lowering blood glucose, but those three short duration injections set the program up to allow insulin to work better,” he says.

When the body senses MDP is present, it increases the amount of a protein in fat tissue, called IR4, which sends out signals that lower blood glucose. “We don’t fully understand how it signals the body to lower blood glucose,” he admits. “We do know it reduces inflammation.”

While that may not sound dramatic, he says they were quite surprised, given that the typical immune response is to increase inflammation. “The postbiotic actually reduced inflammation in fat tissue, which are the tissues that control blood glucose,” he says.

While the results are exciting, he’s quick to point out that “we’re interested in discovery. We’ll leave the clinical aspect to clinicians.” They’d like to achieve a version of MDP that could be taken orally and not injected, but more research will be required. Plus, postbiotics can be a finicky area of research. He describes testing a different postbiotic that's a “a close cousin" to MDP, being "a different type of cell wall that was different by only one peptide.” But that postbiotic made glucose tolerance and inflammation much worse.

However, they also tested what’s called an “orphan drug”—approved only for clinical trials but not likely to make the drug company any money—called mifamurtide, typically used in treating bone cancers. Mifamurtide is synthetic, but chemically identical to the MDP postbiotic. It, too, improved blood glucose and insulin tolerance when administered to mice. The promising part about it is that since the drug is already given to humans in clinical trials, “it could make the transition to humans far more rapid,” he says.

One of their next steps is to expand the models they’re using, starting with age-induced diabetes. “Obesity is only one factor that promotes diabetes,” he says.

The most pressing question now, he says, is “to understand what is actually happening in the gut during obesity.” This compound promises a future in which obesity would pose less of a risk factor for diabetes. And postbiotics hold a lot of potential for future research.

“Postbiotics are a new source of drugs. Bacteria have different physiology from us, and can make all kinds of things that we can’t make,” Schertzer says.

Pioneering Heart Surgeon René Favaloro Is Being Honored With a Google Doodle

Dr. René Favaloro (left) pictured with colleague Dr. Mason Sones.
Dr. René Favaloro (left) pictured with colleague Dr. Mason Sones.
The Cleveland Clinic Center for Medical Art & Photography, Wikimedia Commons // CC BY 4.0

Argentinian heart surgeon René Favaloro is the subject of today’s Google Doodle, which features a sketched portrait of the doctor along with an anatomical heart and several medical tools, The Independent reports.

The renowned doctor was born on this day in 1923 in La Plata, the capital of Argentina’s Buenos Aires province, and pursued a degree in medicine at La Plata University. After 12 years as a doctor in La Pampa, where he established the area’s first mobile blood bank, trained nurses, and built his own operating room, Favaloro relocated to the U.S. to specialize in thoracic surgery at the Cleveland Clinic.

In 1967, Favaloro performed coronary bypass surgery on a 51-year-old woman whose right coronary artery was blocked, restricting blood flow to her heart. Coronary bypass surgery involves taking a healthy vein from elsewhere in the body (in this case, Favaloro borrowed from the patient’s leg, but you can also use a vein from the arm or chest), and using it to channel the blood from the artery to the heart, bypassing the blockage. According to the Mayo Clinic, it doesn’t cure whatever heart disease that caused the blocked artery, but it can relieve symptoms like chest pain and shortness of breath, and it gives patients time to make other lifestyle changes to further manage their disease.

Favaloro wasn’t keen on being called the “father” of coronary bypass surgery, but his work brought the procedure to the forefront of the clinical field. He moved back to Argentina in 1971 and launched the Favaloro Foundation to train surgeons and treat a variety of patients from diverse economic backgrounds.

Favaloro died by suicide on July 29, 2000, at the age of 77, by a gunshot wound to the chest. His wife had died several years prior, and his foundation had fallen deeply into debt, which Argentinian hospitals and medical centers declined to help pay, The New York Times reported at the time.

“As a surgeon, Dr. Favaloro will be remembered for his ingenuity and imagination,” his colleague Dr. Denton A. Cooley wrote in a tribute shortly after Favaloro’s death. “But as a man ... he will be remembered for his compassion and selflessness.” Today would have been his 96th birthday.

[h/t The Independent]

Forget Lab-Grown Meat—You Can Now Buy Lab-Grown Ice Cream

Deagreez/iStock via Getty Images
Deagreez/iStock via Getty Images

Even though “dairy-free” doesn’t necessarily mean “healthier,” it’s still a necessary disclaimer for dairy-free people who are screaming for ice cream. And between veganism, lactose intolerance, and other dietary dairy restrictions, the race is on to create an ice cream for the masses that doesn’t taste like chalk, chemicals, or sadness.

Bay Area startup Perfect Day may have just pulled ahead of the competition. Today, Fast Company reports, it released three flavors of dairy-free ice cream—Vanilla Salted Fudge, Milky Chocolate, and Vanilla Blackberry Toffee—that contain the same proteins found in cow dairy, but grown in a lab from engineered yeast and DNA. Since those proteins contribute greatly to the rich texture and taste of ice cream that we love so much, Perfect Day’s products are supposedly indistinguishable from the real thing.


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The co-founders, vegan bioengineers Ryan Pandya and Perumal Gandhi, got the idea from their experience in medicine, where fermentation is used to grow things in a lab all the time. “The two of us started scratching our heads and wondering, what if we just apply that same exact technology that’s been around for half a century to make the world’s most in-demand, highest-quality protein?” Pandya explained to Fast Company.

Their lactose-, dairy-, and gluten-free vegan ice cream, which they’ve been working on for five years, includes the dairy proteins casein and whey, as well as plant-based fats and sugar. If you're dairy-free because of a casein or whey allergy or sensitivity, you should treat this ice cream like you would any other foods containing dairy, and heed the "Contains milk protein" disclaimer on Perfect Day products.

Lab-grown dairy has environmental benefits too, considering that cows and other livestock are major culprits of greenhouse gas emissions. Pandya and Gandhi hope to sell their proteins to large-scale food manufacturers, and have teamed up with Archer Daniels Midland, an Illinois-based food processing company, to increase production.

Though it seems like a scoop or two of this ice cream might be the recipe for a perfect day, that wasn’t the inspiration behind the company’s name—the founders stumbled upon a study in which scientists discovered that cows produced more milk when listening to music, and one of the most successful songs was Lou Reed’s “Perfect Day.” “As a company on a mission to make cows, people, and the planet happier, it seemed like a perfect fit,” the website says.

Can’t wait to taste the magic? You can purchase all three flavors in a three-pint bundle for $60 here.

[h/t Fast Company]

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