Probiotics for your vision? Healthy gut bacteria could help stop dry eyes

HOUSTON — A recent study suggests that gut bacteria could potentially alleviate dry eyes. Commonly, eye drops, gels, or ointments are the preferred treatments for individuals suffering from dry eyes. However, a group of scientists has discovered that certain bacteria residing in the intestinal tract might offer a new solution.

The intestinal tract comprises the organs through which food and drink pass when they are consumed, digested, absorbed, and subsequently excreted from the body.

A team from the Baylor College of Medicine stumbled upon this discovery when they conducted an experiment with mice, using two different kinds of gut bacteria to observe their effects. They used bacteria from humans afflicted with Sjögren syndrome, a condition causing severe dry eyes, and bacteria from healthy individuals.

The mice that received the bacteria from the Sjögren syndrome patients developed a more severe eye disease under dry conditions compared to those given healthy gut bacteria. These findings suggest that gut bacteria from healthy individuals may have the potential to protect the eye’s surface in dry conditions.

In light of these results, the team concluded that a probiotic bacterial treatment could provide a similar protective effect. To verify this, they conducted another experiment using a dry eye mouse model and an orally administered probiotic bacterial strain named Limosilactobacillus reuteri DSM17938.

Batido de desayuno hecho con yogur probiótico y plátano. (Crédito: 72Point)

DSM17938, a human-derived probiotic bacterial strain, is commercially available and has shown protective effects on the gut and immune system in both humans and mice, although it hasn’t been tested in the context of eye health.

In the experiment, the mice were first treated with antibiotics to eliminate much of the gut’s “friendly” bacteria. The mice were then exposed to extremely dry conditions and given daily doses of either the probiotic bacteria or a saline solution.

After five days, the mice’s eyes were examined for any signs of disease. Those that were fed the probiotic bacteria ended up with significantly healthier eyes than those that were not. These mice also had an increased number of goblet cells, specialized cells that produce mucin, a vital component of tears, in their eye tissue.

Dry eye, a condition where the tears produced by the eye are insufficient to keep the eye properly lubricated, affects around one in 20 people in the United States. Symptoms include eye stinging and burning, inflammation, blurry vision, and light sensitivity. In extreme cases, if left untreated, it can lead to damage to the eye’s surface.

Dr. Laura Schaefer, from Baylor College of Medicine in Texas, suggests that these results indicate that the appropriate oral probiotic could potentially assist in treating and managing dry eye symptoms.

“The ‘friendly’ bacteria that live in the human gastrointestinal tract have been linked to health and protection against disease in many parts of the body, including the gut, brain and lung. It’s therefore not surprising that the gut microbiome also has effects on our eyes,” Schaefer says in a media release.

The findings were presented at the ASM Microbe 2023, the annual meeting of the American Society for Microbiology.

You might also be interested in:

South West News Service writer Alice Clifford contributed to this report.

YouTube video