Helping patients on feeding tubes

Company aims to improve their diets, health

Feeding tubes are lifesavers — literally.

When someone loses the ability to swallow, these life-giving devices provide essential nourishment to the body. More than 437,000 people in the U.S. depend on them, according to a recent Mayo Clinic study.

However, the treatment is not without side effects. In addition to losing the social component to eating, patients may experience bloating, cramping and GI tract infection. The problems can range from annoying to lifethreatening.

Now a startup company, working to advance research performed at the University of Wisconsin-Madison, may offer a way to alleviate these symptoms with plant extracts — or more specifically the tannins they contain.

Tannins can be found in nuts, grains, teas and especially fruits. Grapes and cranberries are particularly rich in tannins, which can be recognized by the puckering, drying sensation in your mouth when you bite into fruit skin or drink red wine. A single fruit contains many different types of tannins.

Fruits and vegetables are part of a healthy diet but are lacking in the liq- uid diets used in tube feeding formulas, said Christian Krueger, a cofounder of the company, Synesis. “We believe that adding tannin is a major step toward that more complete diet.”

Interestingly, tannins are classified as “non-nutritive” because the body can’t break them down and absorb them. But like fiber, which is known to protect against cardiovascular disease, non-nutritive components in food can still provide health benefits.

The company’s current efforts expand on a 2013 study from UW-Madison that evaluated the effects of tube feeding and cranberry tannins on the small intestines of mice. The small intestines were of particular interest because they absorb nutrients and serve as part of the immune system.

“It’s probably pretty underappreciated that greater than 70% of the body’s immune system is associated with the digestive system,” said Krueger.

In healthy mice (and humans), the plump fingerlike villi that carpet the inside of the small intestines remain packed close together and coated in a thick layer of mucus. The mucus forms a physical and chemical barrier against the 100 trillion naturally occurring gut bacteria, food and any pathogens passing through.

At the end of the UW-

Madison experiment, the intestines of mice that were tube-fed formula had been compromised. Gaps had formed between the villi and mucus production had decreased. These structural changes impaired the organ’s immune response by reducing its ability to function as an effective barrier.

On the other hand, the small intestines of mice that were tubefed formulas containing tannins looked almost indistinguishable from the healthy intestines of mice fed solid food.

More research must be performed to understand exactly how tannins stimulate the small intestine and keep it functioning properly, though Krueger suspects that the effect is partly due to the diversity of tannins found in plants.

“The plant-derived tannin extract is causing the intestine to go on alert,” said Krueger. If the intestine sees the same set of simple nutrients every day, as happens with conventional formulas, it is not ready for a challenge. “If it sees novel things, the guards are forced to pay attention.”

Since obtaining patent approval at the end of 2016, Synesis has started designing a trial to test the effectiveness of tannin extracts in humans who use feeding tubes.

Positive results will allow tannins to be categorized as a “medical food” by the U.S. Food and Drug Administration. Medical foods are prescribed by a doctor but are less regulated than drugs because they are already “generally recognized as safe.”

Even if the trial results are promising, Lynn Koepke, a registered dietitian nutritionist at Home Care Medical Inc., cautions that insurance coverage could limit accessibility to the product. Koepke has worked with patients who require tube feeding for over 25 years.

Medicare and Medicaid base reimbursement on the calories a treatment provides. Since tannins are not digested and do not provide calories, reimbursement could be insufficient to promote its use.

Private insurance coverage can vary, said Koepke. While some plans may treat formula as a medical expense, others “may consider formula no different that groceries.”

Rather than being offered as a stand-alone product, “it would be optimal if the study results provided adequate clinical justification to have the tannins added to commercially-prepared formulas,” Koepke said. Maintaining low production costs will also motivate

formula manufacturers to adopt the extract.

Krueger hopes to have a marketable product in the next 18 months. “We

aim to produce results that are better than what’s on the market. Our goal is to improve health and quality of life.”