Today we talk about an exciting Spanish discovery in the world of nutrition and neuroscience, which can have a positive impact on the development of new therapies that improve children’s neurodevelopment. A team of experts from the “José Mataix” Institute of Nutrition and Food Technology and the Institute of Neurosciences of the University of Granada (UGR), together with researchers from the prestigious German center Helmholtz-Centre for Environmental Research (Leipzig), have discovered an interesting link between the microorganisms that live in our intestine and our ability to think and remember. This finding focuses on how the intestinal microbiota, that is, the set of microorganisms that inhabit our digestive system, can influence cognition, which includes processes such as intelligence and memory.
This study suggests that certain beneficial microorganisms, known as probiotics, and some products derived from the amino acid histidine, could play a role in the development of these cognitive functions. This research could open the door to new ways to improve brain development in children, possibly through the use of probiotic compounds or microorganisms.
The results of this study, led by Professor Antonio Suárez, professor of Biochemistry and Molecular Biology at the University of Granada, have been published in the scientific journal Cell Host & Microbe. This work represents a significant step in our understanding of how gut health may be linked to brain function.
In the last ten years, various studies have deepened our knowledge about how intestinal microorganisms have a great influence on the brain, demonstrating the existence of what we know as the microbiota-brain axis”, a two-way communication between our intestine and our brain. brain, which is carried out through chemical signals, neuronal connections and the immune system.
These scientific works have revealed that changes or imbalances in the microbiota may be related to brain development diseases, such as autism; neurodegenerative diseases, such as Parkinson’s, Alzheimer’s and multiple sclerosis; or with behavioral problems such as anxiety, depression and attention deficit hyperactivity disorder. However, until now, it was not well understood how the microbiota specifically affected brain development in children.
Colonization by the microbiota in a newborn begins at birth and continues to evolve during the first years of life. This period of maturation of the microbiota occurs simultaneously with physiological and functional changes in the development of the child’s brain, which in this stage experiences rapid growth and begins to develop skills in areas such as language, motor skills, thinking and social interaction. It is in these early years that the foundations of the long-term relationship between the microbiota and the brain are established, known as the microbiota-brain axis. Therefore, any alteration in the normal development of the microbiota during this critical period could have an impact on cognitive functions that are in the process of maturation, with possible consequences that extend throughout life.
Role of probiotics and histidine in cognitive development
In recent research, scientists have made an interesting discovery about the relationship between microorganisms in our gut and mental development in babies. Using the Bailey test, which evaluates aspects such as motor, cognitive, socio-emotional and language development, they found that the composition of the microbiota in 6-month-old babies varies according to their performance in these tests.
Most notably, they identified an enzyme called histidase, present in the microbiota, which appears to be linked to babies’ cognitive ability. This enzyme is related to the metabolism of histidine, an amino acid already associated with cognitive function. They confirmed this relationship by observing that the profiles of metabolites derived from histidine differed depending on the cognitive behavior of the babies.
To test their findings, the researchers carried out an experiment by fecally transplanting the babies’ microbiota into mice that do not have their own microorganisms, known as axenic or germ-free mice. This trial was carried out with the help of the Animal Experimentation Unit of the Scientific Instrumentation Center of the UGR, the only place in Spain that has this type of mice.
Germ-free mice are a unique research tool as they are born and raised without microbes, in a completely sterile environment. This characteristic makes them a valuable resource to study the relationship between the microbiota and the brain. In the absence of microbiota, these mice experience notable changes in various aspects of the brain, such as neurotransmitters, the formation of synaptic connections, and the size of certain brain areas. These changes translate into differences in their movement, behavior and memory compared to normal mice that do have intestinal microbiota as standard.
In one experiment, researchers used an object recognition test, common in mouse studies, to assess memory. Mice that were transplanted with the microbiota from babies with better cognitive performance showed a higher memory capacity than those mice that received the microbiota from babies with lower cognitive ability. Additional analyzes revealed that certain bacteria, specifically from the genera Phocaeicola, Bacteroides, and Bifidobacterium, are positively associated with intelligence and memory.
In addition, differences were observed in the levels of certain metabolites such as urocanate, glutamate and histidine in the perirhinal cortex of the mice, which is a key brain region for memory. These findings help to complete the understanding of the molecular mechanism involved.
With the understanding of this mechanism, the results suggest that certain probiotic bacteria, such as those of the genus Bifidobacterium, and histidine metabolites, either separately or in combination, could improve memory and cognitive ability in children. This is especially relevant in pediatric diseases that involve cognitive deficits, such as autism or hyperactivity disorder.
The microbiota refers to the vast set of microorganisms that live in symbiosis with us, mainly housed in our digestive system. Understanding and maintaining a proper balance of these microorganisms is vital to our health and well-being. They play an essential role in numerous processes in the human body. For example, they aid in the digestion and absorption of nutrients, contribute to the regulation of the immune system and metabolism, participate in energy production, the synthesis of vitamins and neurotransmitters, and in maintaining the barrier function of the intestinal lining. . Additionally, they offer protection against pathogens and play a role in regulating the body’s inflammatory response.
Source: University of Granada
