Highlights

  • A probiotic isolated from centenarians called LTL1361 mixed with dietary fiber alleviates age-related cognitive impairment and protects the brain of healthy aging mice.
  • This probiotic and dietary fiber combination also improves gut function and reduces inflammation in the blood and colon.
  • These findings suggest the LTL1361 and dietary fiber mixture as a novel and promising anti-aging agent in humans.

Accumulating evidence indicates that gut microbiota regulates host health. This microorganism population can be manipulated in multiple ways: with probiotics to change the variety and with dietary nutrients or fiber to supply specific compounds. While studies have focused on the anti-aging effects within a particular disease, the evidence is limited for the anti-aging effects of centenarian-sourced probiotics combined with a dietary fiber complex.

Researchers from Guangxi University in China reveal the anti-aging effects of an isolated probiotic strain from healthy centenarians’ feces mixed with dietary fiber. With three months of treatment, this combination improved learning and memory ability, antioxidant capacity, and inflammation markers in aged mice. Published in the journal Nutrients, the researchers suggest that probiotics and dietary fiber combination might be used as a novel and promising anti-aging synbiotic agent in humans.

Fighting Aging with Feces-Sourced Probiotics and Fiber

As aging is inevitable and its relative negative symptoms are complicated, we tend to pursue anti-aging treatments, ranging from diets to drugs. Accumulating evidence has indicated that prebiotics and probiotics could affect our health by regulating our gut microbiota.

Prebiotics — a form of dietary fiber that feeds the “friendly” bacteria in your gut — are resistant to digestion and absorption during passage through the stomach and small intestine but can be fermented in the large intestine by gut bacteria. This dietary fiber can influence our gut bacteria to produce beneficial metabolites, such as short-chain fatty acids (SCFAs). But data indicate that daily dietary fiber intake for the elderly is roughly 40% below the recommended adequate intake. For example, concentrations of SCFAs, which may promote weight loss and provide various health benefits, are less optimal in the elderly.

Live microorganisms called probiotics — like the ones advertised in cultured dairy products (e.g., yogurt and kefir) — administered in adequate amounts exert health benefits to the host. Probiotic strains derived from the elderly exhibit excellent antioxidant, cholesterol-lowering, and immune-regulating activities. Lactobacillus is the largest probiotic group with a high possibility of developing functional food. However, individual bacterial strains always exhibit unique bioactivities that require experimental confirmation. Several Lactobacillus strains have been reported to have anti-aging effects due to their radical-scavenging activity and oxidation stress-attenuating ability.

Centenarian-Sourced Probiotic and Dietary Fiber Improve Aging in Mice

Previously, the Guangxi University research team isolated a strain of Lactobacillus — which they named LTL1361 — from the feces of healthy centenarians living in Bama, China, and demonstrated its potential probiotic properties in preliminary research in cultured cells. In this study, Ren and colleagues examined the anti-aging effects of the LTL1361 strain and dietary fiber on learning and memory ability, antioxidant capacity, inflammation markers, and SCFAs in natural aging mice.

Using the Morris water maze test of spatial memory, the Guangxi University researchers evaluated the effects of dietary fiber and LTL1361 on cognitive abilities in aged mice. Researchers used the Morris water maze to study spatial memory and learning. In this test, animals are repeatedly placed in an opaque pool of water surrounded by environmental cues, where they are tracked as they learn to find a hidden escape platform. The researchers observed a reduction in the time it took aged mice treated with dietary fiber or LTL136 to find the platform. The results revealed that the combination of dietary fiber and centenarian-sourced LTL1361 significantly improved learning and memory ability.


(Ren et al., 2022 | Nutrients) The effects of dietary fiber and Lactobacillus LTL1361 on swimming performance in the spatial memory test. The Morris water maze (MWM) is a test of spatial learning for rodents that relies on distal cues to navigate from start locations around the perimeter of an open swimming arena to locate a submerged escape platform. These plots show several parameters measured during the spatial memory test: (A) escape latency; (B) the number that crossed platform; (C) time in the target quadrant. DFC, dietary fiber complex; LTL1361, Lactobacillus strain from centenarians.

In addition to improving learning and memory, Ren and colleagues showed that the combination of dietary fiber and Lactobacillus LTL1361 protected intestinal wall function and areas of the brain associated with cognition (pyramidal neurons) and learning/memory (hippocampus). Furthermore, LTL1361 and dietary fiber decreased oxidative stress and inflammation and increased the availability of SCFAs in the small intestine.

Can Probiotics and Fiber Improve Human Aging?

The combination of dietary fiber and Lactobacillus LTL1361, which is a  synbiotic (mixture of probiotics and prebiotics) seems like a promising treatment for cognitive decline in the elderly. Nevertheless, further studies are required to clarify the biological connection between our gut, the microorganisms living within our gut, and how they affect our brain during aging. 

Most of the latest clinical research has focused on applying commercial probiotics (one strain or a cocktail) to healthy older people. The results indicate that probiotic consumption may positively impact by increasing the levels of specific beneficial gut microbe populations or modifying subpopulations of Lactobacillus. These studies show that probiotics can enhance the immune response and improve bowel movements, among other beneficial effects.

Other studies have shown that the health benefits of probiotics are related to their ability to revert age-related increases of opportunistic pathogens, such as Clostridium difficile, which are involved in antibiotic-associated diarrhea that impact nutrition and inflammatory status. In the elderly, C. difficile-associated diarrhea was linked to a reduction in the number of Bifidobacteria. For this reason, therapies based on the use of probiotics to correct the microbiota imbalance seem promising. However, current guidelines do not recommend their administration. Notwithstanding the promising results, other studies reported controversial ones, most of them having no significant effects.