Good as new? Scientists target gut microbes to reverse the effects of aging in middle age

16 May 2019 --- Modifying gut microbes through diet can lessen inflammation in the brain of middle-aged male mice and could positively influence brain aging and function, a new study has found. It comes at a time of increasing research into the gut-brain axis, which highlights how gut microbes can regulate brain function, including emotional processing and behavior. The research shows that a diet supplemented with prebiotics reversed microglia activation in the middle-aged mouse brain towards young adult levels.

The findings suggest that prebiotic dietary fibers could be developed as a mechanism to promote healthy aging by protecting brain function and prevent the adverse effects of age-related neuroinflammation.

Scientists examined the possibility that microbes can reverse the effects of aging in middle age, a time of life when various physiological changes occur. This can lead to alterations of brain function, including cognitive impairments, but the mechanisms underpinning such changes are unclear.

The research involved examining prebiotics – non-digestible fibers that promote the growth of beneficial bacteria in the intestines – and, in particular, inulin, a prebiotic found in a multitude of fruit, vegetables (artichokes, asparagus, chicory, leeks and onions), herbs and wheat.

“We wanted to see whether an inulin enriched diet that can modulate the composition of the microbes in the gut could also improve brain health and wellbeing,” says Professor Cryan, leader of this research. “The community of microbes in the gut changes with aging. Many studies in aging focus on very old animals and this may be too late to reverse the age-associated changes. We chose middle age in the hope that we could promote healthy aging.”

“Our research shows that a diet supplemented with prebiotics reversed microglia activation in the middle-aged mouse brain towards young adult levels,” adds Dr. Marcus Boehme. “Moreover, this reversing effect was observed in a key region of the brain which regulates learning and memory, the hippocampus,” he explains. “Microglia are the major immune cells in the brain and have shown to be a key player in neuropsychological and neurodegenerative conditions. Moreover, microglia play a crucial role in brain plasticity and cognition.”

The study is published in the journal Molecular Psychiatry and the research was supported by the Science Foundation Ireland Centre grant to the APC Microbiome Ireland and the European-wide JPI-HDHL-NutriCog project AMBROSIAC.

Other recent research in the gut-brain axis space includes a supplement containing 14 strains of “gut-friendly” bacteria which was shown to significantly reduce both the frequency and severity of migraine headaches in adults.

There is also mounting evidence linking imbalances in the microbial species that make up the gut microbiome to a number of health problems including allergies, autoimmune disorders and psychiatric mood disorders. Probiotics have even been flagged as a potential avenue of treatment to alleviate bipolar and other psychiatric mood disorders, such as depression.

Meanwhile, in February researchers at the European Molecular Biology Laboratory's (EMBL) European Bioinformatics Institute (EBI) and the Wellcome Sanger Institute have identified almost 2,000 gut bacterial species, using a range of computational methods. The objective is that by having a larger “map” of the bacterial species found in the gut, researchers can analyze individual microbiomes much more accurately.

In addition, the importance of fiber is also intimately tied with gut microbes. A healthy, fibrous diet feeds and allows the gut bacteria to thrive. In turn, they increase and enhance the gut microbiome. Fibers are essential for a healthy gut microbe and the more microbes that are in the intestine, the thicker the mucus wall and the better the barrier between the body and the bacterial population.

Essentially, functional fibers can enter a range of markets and applications. As their gut-health benefits are more widely understood, consumers are seeking out food and beverage products that come with the fiber and gut health tag.

NutritionInsight has reached out to UCC for more information.

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