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Protein intake and amino acid supplementation regulate exercise recovery and performance through the modulation of mTOR, AMPK, FGF21, and immunity.
Torre-Villalvazo, I, Alemán-Escondrillas, G, Valle-Ríos, R, Noriega, LG
Nutrition research (New York, N.Y.). 2019;:1-17
Abstract
Exercise is considered to be the best approach to improve quality of life, and together with a healthy and adequate dietary pattern, exercise represents the best strategy to reduce the risk of chronic metabolic and inflammatory diseases, such as those related to obesity. The regularity and intensity of exercise is modulated at the molecular level in the skeletal muscle by two protein kinases, the mechanistic target of rapamycin (mTOR) and AMP-activated protein kinase (AMPK), which act as sensors of external stimuli, showing the energy status of muscular fibers. The mTOR pathway is activated by insulin and amino acid availability, and its metabolic actions culminate in increased protein synthesis and reduced autophagy, leading to an increase in muscle mass. In contrast, AMPK activation induces a transcriptional program aimed to increase the mitochondrial content in skeletal muscle, transforming fast-twitch glycolytic fibers to slow-twitch oxidative fibers and increasing resistance to fatigue. In addition, inadequate exercise training induces imbalance in the immune response, generating excessive inflammation and/or immunosuppression. The purpose of this review is to summarize recent studies that provide insight into dietary protein interventions and/or amino acid supplementation that may improve outcomes after exercise by modulating 1) mTOR and AMPK activation during early exercise recovery, leading to increased muscle protein synthesis or increased oxidative capacity; 2) undesirable inflammatory responses; and 3) fibroblast growth factor 21 (FGF21) levels that may have relevant implications in skeletal muscle metabolism, particularly during the exercise recovery and performance of obese subjects.
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2.
Immune Function and Micronutrient Requirements Change over the Life Course.
Maggini, S, Pierre, A, Calder, PC
Nutrients. 2018;(10)
Abstract
As humans age, the risk and severity of infections vary in line with immune competence according to how the immune system develops, matures, and declines. Several factors influence the immune system and its competence, including nutrition. A bidirectional relationship among nutrition, infection and immunity exists: changes in one component affect the others. For example, distinct immune features present during each life stage may affect the type, prevalence, and severity of infections, while poor nutrition can compromise immune function and increase infection risk. Various micronutrients are essential for immunocompetence, particularly vitamins A, C, D, E, B2, B6, and B12, folic acid, iron, selenium, and zinc. Micronutrient deficiencies are a recognized global public health issue, and poor nutritional status predisposes to certain infections. Immune function may be improved by restoring deficient micronutrients to recommended levels, thereby increasing resistance to infection and supporting faster recovery when infected. Diet alone may be insufficient and tailored micronutrient supplementation based on specific age-related needs necessary. This review looks at immune considerations specific to each life stage, the consequent risk of infection, micronutrient requirements and deficiencies exhibited over the life course, and the available evidence regarding the effects of micronutrient supplementation on immune function and infection.
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3.
The developing gut microbiota and its consequences for health.
Butel, MJ, Waligora-Dupriet, AJ, Wydau-Dematteis, S
Journal of developmental origins of health and disease. 2018;(6):590-597
Abstract
The developmental origin of health and disease highlights the importance of the period of the first 1000 days (from the conception to the 2 years of life). The process of the gut microbiota establishment is included in this time window. Various perinatal determinants, such as cesarean section delivery, type of feeding, antibiotics treatment, gestational age or environment, can affect the pattern of bacterial colonization and result in dysbiosis. The alteration of the early bacterial gut pattern can persist over several months and may have long-lasting functional effects with an impact on disease risk later in life. As for example, early gut dysbiosis has been involved in allergic diseases and obesity occurrence. Besides, while it was thought that the fetus developed under sterile conditions, recent data suggested the presence of a microbiota in utero, particularly in the placenta. Even if the origin of this microbiota and its eventual transfer to the infant are nowadays unknown, this placental microbiota could trigger immune responses in the fetus and would program the infant's immune development during fetal life, earlier than previously considered. Moreover, several studies demonstrated a link between the composition of placental microbiota and some pathological conditions of the pregnancy. All these data show the evidence of relationships between the neonatal gut establishment and future health outcomes. Hence, the use of pre- and/or probiotics to prevent or repair any early dysbiosis is increasingly attractive to avoid long-term health consequences.
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4.
From Infections to Anthropogenic Inflicted Pathologies: Involvement of Immune Balance.
Lee, F, Lawrence, DA
Journal of toxicology and environmental health. Part B, Critical reviews. 2018;(1):24-46
Abstract
A temporal trend can be seen in recent human history where the dominant causes of death have shifted from infectious to chronic diseases in industrialized societies. Human influences in the current "Anthropocene" epoch are exponentially impacting the environment and consequentially health. Changing ecological niches are suggested to have created health transitions expressed as modifications of immune balance from infections inflicting pathologies in the Holocene epoch (12,000 years ago) to human behaviors inflicting pathologies beginning in the Anthropocene epoch (300 years ago). A review of human immune health and adaptations responding to environmental (biological, chemical, physical, and psychological) stresses, which are influenced by social conditions, emphasize the involvement of fluctuations in immune cell subsets affecting influential gene-environment interactions. The literature from a variety of fields (anthropological, immunological, and environmental) is incorporated to present an expanded perspective on shifts in diseases within the context of immune balance and function and environmental immunology. The influences between historical and contemporary human ecology are examined in relation to human immunity. Several examples of shifts in human physiology and immunity support the premise that increased incidences of chronic diseases are a consequence of human modification of environment and lifestyle. Although the development of better health care and a broader understanding of human health have helped with better life quality and expectancy, the transition of morbidity and mortality rates from infections to chronic diseases is a cause for concern. Combinations of environmental stressors/pollutants and human behaviors and conditions are modulating the immune-neuroendocrine network, which compromises health benefits.
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5.
The Microbiotic Highway to Health-New Perspective on Food Structure, Gut Microbiota, and Host Inflammation.
Hansen, NW, Sams, A
Nutrients. 2018;(11)
Abstract
This review provides evidence that not only the content of nutrients but indeed the structural organization of nutrients is a major determinant of human health. The gut microbiota provides nutrients for the host by digesting food structures otherwise indigestible by human enzymes, thereby simultaneously harvesting energy and delivering nutrients and metabolites for the nutritional and biological benefit of the host. Microbiota-derived nutrients, metabolites, and antigens promote the development and function of the host immune system both directly by activating cells of the adaptive and innate immune system and indirectly by sustaining release of monosaccharides, stimulating intestinal receptors and secreting gut hormones. Multiple indirect microbiota-dependent biological responses contribute to glucose homeostasis, which prevents hyperglycemia-induced inflammatory conditions. The composition and function of the gut microbiota vary between individuals and whereas dietary habits influence the gut microbiota, the gut microbiota influences both the nutritional and biological homeostasis of the host. A healthy gut microbiota requires the presence of beneficial microbiotic species as well as vital food structures to ensure appropriate feeding of the microbiota. This review focuses on the impact of plant-based food structures, the "fiber-encapsulated nutrient formulation", and on the direct and indirect mechanisms by which the gut microbiota participate in host immune function.
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6.
The Transcription Factor EB Links Cellular Stress to the Immune Response
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Nabar, NR, Kehrl, JH
The Yale journal of biology and medicine. 2017;(2):301-315
Abstract
The transcription factor EB (TFEB) is the master transcriptional regulator of autophagy and lysosome biogenesis. Recent advances have led to a paradigm shift in our understanding of lysosomes from a housekeeping cellular waste bin to a dynamically regulated pathway that is efficiently turned up or down based on cellular needs. TFEB coordinates the cellular response to nutrient deprivation and other forms of cell stress through the lysosome system, and regulates a myriad of cellular processes associated with this system including endocytosis, phagocytosis, autophagy, and lysosomal exocytosis. Autophagy and the endolysosomal system are critical to both the innate and adaptive arms of the immune system, with functions in effector cell priming and direct pathogen clearance. Recent studies have linked TFEB to the regulation of the immune response through the endolysosmal pathway and by direct transcriptional activation of immune related genes. In this review, we discuss the current understanding of TFEB's function and the molecular mechanisms behind TFEB activation. Finally, we discuss recent advances linking TFEB to the immune response that positions lysosomal signaling as a potential target for immune modulation.
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7.
Bacterial Colonization of the Newborn Gut, Immune Development, and Prevention of Disease.
Walker, WA
Nestle Nutrition Institute workshop series. 2017;:23-33
Abstract
We now know that the fetus does not reside in a sterile intrauterine environment but is exposed to commensal bacteria from the maternal gut which cross the placenta and infiltrate the amniotic fluid. This exposure to colonizing bacteria continues at birth and during the first year of life, and it has a profound influence on lifelong health. Why is this important? Cross talk with colonizing bacteria in the developing neonatal intestine helps in the initial adaptation of the infant to extrauterine life, particularly in acquiring immune homeostasis, and provides protection against disease expression (e.g., allergy, autoimmune disease, and obesity) later in life. Colonizing intestinal bacteria are critical to the development of host defense during the neonatal period. Disrupted colonization (dysbiosis) due to cesarean section delivery, perinatal antibiotics, or premature delivery may adversely affect the development of host defense mechanisms in the gut and predispose to inflammation leading to increased susceptibility to disease later in life. Clinical evidence suggests that babies born by cesarean section have higher incidence rates of allergy, type 1 diabetes, and obesity. Infants given repeated antibiotic regimens are more likely to have asthma as adolescents. This observation helps to explain the disease paradigm shift in children from developed countries.
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8.
Dysbiosis and Immune Dysregulation in Outer Space.
Cervantes, JL, Hong, BY
International reviews of immunology. 2016;(1):67-82
Abstract
In space, the lifestyle, relative sterility of spaceship and extreme environmental stresses, such as microgravity and cosmic radiation, can compromise the balance between human body and human microbiome. An astronaut's body during spaceflight encounters increased risk for microbial infections and conditions because of immune dysregulation and altered microbiome, i.e. dysbiosis. This risk is further heightened by increase in virulence of pathogens in microgravity. Health status of astronauts might potentially benefit from maintaining a healthy microbiome by specifically managing their diet on space in addition to probiotic therapies. This review focuses on the current knowledge/understanding of how spaceflight affects human immunity and microbiome.
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9.
Physiological Role of Gut Microbiota for Maintaining Human Health.
Andoh, A
Digestion. 2016;(3):176-81
Abstract
BACKGROUND The human body is colonized by an extremely complex and abundant aggregation of microbes, collectively referred to as the gut microbiota. Recent studies have focused on the link between these microbes and our health. SUMMARY Diet contributes to shaping the gut microbial structure and influences metabolic functions of the host. Alteration of the microbial structure and function (dysbiosis) is associated with the pathogenesis of various disorders. Fermentation is the process by which anaerobic bacteria (Firmicutes and Bacteroidetes) break down indigestible carbohydrates to short-chain fatty acids (SCFAs; acetate, propionate and butyrate), collaborating with species specialized in oligosaccharide fermentation (e.g. Bifidobacteria). Butyrate and propionate can regulate intestinal physiology and immune function, while acetate acts as a substrate for lipogenesis and gluconeogenesis. The gut microbiota regulates immune homeostasis via the induction of regulatory T cells and Th17 cells. In addition, butyrate has strong anti-inflammatory effects possibly through the inhibition of histone deacetylase activity. Metabolic products generated by the gut microbiota, such as SCFAs, GABA, tryptophan, serotonin and catecholamine, transmit a signal to resident cells in the gut. KEY MESSAGE Advances made in the DNA sequencing technology and bioinformatics have revolutionized our understanding of the microbes in the gut.
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10.
Ocular Immunity and Inflammation.
Albini, TA, Davis, JL
Developments in ophthalmology. 2016;:38-45
Abstract
Complex immunologic mechanisms are involved in multiple intraocular diseases. The field of immunology has aided greatly in better understanding and treating inflammation in the posterior segment. While traditional therapy has relied on drugs such as corticosteroids and antimetabolites that exert there effects by multiple mechanisms, the more recently developed biologic immune modulators involve specific mechanisms of action with the potential to significantly reduce side effects relative to more traditional agents. Better understanding of diseases such as age-related macular degeneration or diabetic retinopathy has led to the appreciation of immune mechanisms involved in these diseases and has suggested potential targets for therapy.