Page 81 - Petelin, Ana, ur. 2021. Zdravje starostnikov / Health of the Elderly. Zbornik povzetkov z recenzijo / Book of Abstracts. Koper: Založba Univerze na Primorskem/University of Primorska Press
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gut microbiota in the elderly prehrana in zdravje starejših odraslih | nutrition and health of the elderly
Karin Šik Novak; Zala Jenko Pražnikar
University of Primorska, Faculty of Health Sciences, Izola, Slovenia
Introduction. The human gastrointestinal tract represents the biggest microbial
community in the human body. Gut bacteria regulate extraction, synthesis and
absorption of many nutrients and metabolites, such as bile acids, lipids, amino
acids, vitamins, and short-chain fatty acids. Aging is a genetically-determined
process that leads to a decline of physiological functions. One of the most rec-
ognized effects of aging is the age-associated immune deregulation. Gut dysbio-
sis can trigger the immune response and chronic low-grade inflammation, lead-
ing to age-related degenerative pathologies and unhealthy aging. An adequate
nutritional status is important to maintain the functionality of the immune sys-
tem and preventing frailty and cognitive function impairment in the elderly.
Methods. A scientific literature search was performed by accessing the data-
bases PubMed, GoogleScholar and ScienceDirect using the following keywords
and their combinations: »gut microbiota«, »elderly«, »longevity«, »Alzheimer’s
disease«, »nutrition«, limiting the search to the last 10 years. The review was
focused on the changes of gut microbiota during aging, the effect of nutrition
and its link to pathologies.
Results. Gut microbiota diversity increases from birth and at about the age of
three, the gut microbiota composition is mostly mature. In the elderly, chang-
es in dietary habits, digestion, nutrient absorption and immune activity can af-
fect gut microbiota composition. The microbiota-gut-brain axis is a bidirec-
tional communication system that is connected via neural, immune, endocrine,
and metabolic pathways and plays a key role in the modulation of brain func-
tions. Research shows a link between the gut microbiota and Alzheimer’s dis-
ease (AD), which is characterized by the accumulation of amyloid-β and tau in
the brain, leading to cognitive impairment. The increased gut and blood-brain
barrier permeability induced by gut dysbiosis may affect pathogenesis of AD
and other neurodegenerative disorders. Nutritional strategies aiming at micro-
biota and immune modulation in the elderly are especially relevant due to their
higher susceptibility to disease, malnutrition, impairment of the gut microbio-
ta and a pro-inflammatory status of the immune system. Animal studies show
that interventions with antibiotics, microbial infections, prebiotics, probiotics
and fecal microbiota transplantation not only affect gut microbiota composi-
tion, but also influence cognitive impairment related to AD. Analysis of the gut
microbiota and its potential for modulation to improve health are important el-
ements in the process of improving health of the elderly.
Discussion and conclusions. Nutritional strategies for the elderly should consider
the nutritional deficiencies and needs, but also the gut microbiota, the immune
system and cognitive function. More research is needed to better understand
the changes in gut microbiota over the lifespan and associated pathologies.
Keywords: microbiota, elderly, health
79
Karin Šik Novak; Zala Jenko Pražnikar
University of Primorska, Faculty of Health Sciences, Izola, Slovenia
Introduction. The human gastrointestinal tract represents the biggest microbial
community in the human body. Gut bacteria regulate extraction, synthesis and
absorption of many nutrients and metabolites, such as bile acids, lipids, amino
acids, vitamins, and short-chain fatty acids. Aging is a genetically-determined
process that leads to a decline of physiological functions. One of the most rec-
ognized effects of aging is the age-associated immune deregulation. Gut dysbio-
sis can trigger the immune response and chronic low-grade inflammation, lead-
ing to age-related degenerative pathologies and unhealthy aging. An adequate
nutritional status is important to maintain the functionality of the immune sys-
tem and preventing frailty and cognitive function impairment in the elderly.
Methods. A scientific literature search was performed by accessing the data-
bases PubMed, GoogleScholar and ScienceDirect using the following keywords
and their combinations: »gut microbiota«, »elderly«, »longevity«, »Alzheimer’s
disease«, »nutrition«, limiting the search to the last 10 years. The review was
focused on the changes of gut microbiota during aging, the effect of nutrition
and its link to pathologies.
Results. Gut microbiota diversity increases from birth and at about the age of
three, the gut microbiota composition is mostly mature. In the elderly, chang-
es in dietary habits, digestion, nutrient absorption and immune activity can af-
fect gut microbiota composition. The microbiota-gut-brain axis is a bidirec-
tional communication system that is connected via neural, immune, endocrine,
and metabolic pathways and plays a key role in the modulation of brain func-
tions. Research shows a link between the gut microbiota and Alzheimer’s dis-
ease (AD), which is characterized by the accumulation of amyloid-β and tau in
the brain, leading to cognitive impairment. The increased gut and blood-brain
barrier permeability induced by gut dysbiosis may affect pathogenesis of AD
and other neurodegenerative disorders. Nutritional strategies aiming at micro-
biota and immune modulation in the elderly are especially relevant due to their
higher susceptibility to disease, malnutrition, impairment of the gut microbio-
ta and a pro-inflammatory status of the immune system. Animal studies show
that interventions with antibiotics, microbial infections, prebiotics, probiotics
and fecal microbiota transplantation not only affect gut microbiota composi-
tion, but also influence cognitive impairment related to AD. Analysis of the gut
microbiota and its potential for modulation to improve health are important el-
ements in the process of improving health of the elderly.
Discussion and conclusions. Nutritional strategies for the elderly should consider
the nutritional deficiencies and needs, but also the gut microbiota, the immune
system and cognitive function. More research is needed to better understand
the changes in gut microbiota over the lifespan and associated pathologies.
Keywords: microbiota, elderly, health
79
