Probiotics and their Role in Mitigating Cognitive Decline
Probiotics and their Role in Mitigating Cognitive Decline
Aryan M. Yazdani,1,*
1. Msc. student of Clinical nutrition Shiraz university of medical sciences
Introduction: The gut microbiota, a group of microorganisms residing in our intestines is now acknowledged as playing a crucial role in promoting our general well-being. Within this community, probiotics refer to bacteria and yeasts that particularly support the digestive system. Recent studies have started to suggest a connection, between these gut microorganisms and our brain leading to the notion of the gut-brain axis.
Methods: The Gut-Brain Axis
The gut-brain axis is about the two-way communication between the central nervous system and the enteric nervous system. Recent research indicates that our gut microbiota can influence this axis, which in turn can affect our brain function and behavior. Scientists believe that this impact is caused by factors, such, as the vagus nerve, immune system, gut hormones, and microbial metabolites.
Probiotics and Cognitive Health
Recent studies are suggesting that alterations in the gut microbiota composition and function can influence neurodevelopment, cognition, mood, and behavior). Dysbiosis or imbalance in the gut microbiota has been associated with a variety of neurological and psychiatric disorders, including Alzheimer's disease, Parkinson's disease, depression, and autism spectrum disorde. Therefore, strategies aiming to correct dysbiosis, such as the use of probiotics, are being explored for their potential therapeutic benefits.
Several studies have reported beneficial effects of probiotics on cognitive function. For example, a randomized, double-blind, controlled clinical trial found that a 12-week intervention with a probiotic mix (Lactobacillus and Bifidobacterium strains) improved cognitive function in patients with Alzheimer's disease. Another 12-week randomized controlled trial showed that daily consumption of a fermented milk product containing four probiotic strains could beneficially alter brain activity in healthy women.
Results: Potential Mechanisms
The exact mechanisms by which probiotics may exert their beneficial effects on cognitive function are not yet fully understood. However, several potential mechanisms have been proposed.
One theory is that probiotics may modulate the immune system, reducing the systemic inflammation that is thought to contribute to cognitive disorders such as Alzheimer's disease. Another theory suggests that probiotics may help maintain the integrity of the blood-brain barrier, which becomes compromised in many neurological disorders.
Probiotics may also produce and enhance the bioavailability of neuroactive substances, such as gamma-aminobutyric acid (GABA), serotonin, and dopamine, which can influence mood and cognition. Furthermore, probiotics might modulate the gut-brain axis by interacting with the enteric nervous system, thereby affecting gastrointestinal motility and secretion, and influencing the sensory and motor functions of the central nervous system.
Conclusion: While the research into probiotics and cognitive decline is still in its early stages, the evidence thus far is promising. Probiotics offer a potentially safe and cost-effective strategy to complement traditional therapies for cognitive disorders. However, more rigorous, large-scale clinical trials are needed to confirm these preliminary findings and to clarify the mechanisms by which probiotics may exert their beneficial effects on the brain.
Further research is also required to identify the most effective probiotic strains, as well as the optimal dosage and duration of treatment.