1 4337 125 MICROTUBULES AS MAJOR REGULATORS OF ENDOTHELIAL FUNCTION: IMPLICATION FOR LUNG INJURY. ENDOTHELIAL DYSFUNCTION HAS BEEN ATTRIBUTED AS ONE OF THE MAJOR COMPLICATIONS IN COVID-19 PATIENTS, A GLOBAL PANDEMIC THAT HAS ALREADY CAUSED OVER 4 MILLION DEATHS WORLDWIDE. THE DYSFUNCTION OF ENDOTHELIAL BARRIER IS CHARACTERIZED BY AN INCREASE IN ENDOTHELIAL PERMEABILITY AND INFLAMMATORY RESPONSES, AND HAS EVEN BROADER IMPLICATIONS IN THE PATHOGENESIS OF ACUTE RESPIRATORY SYNDROMES SUCH AS ARDS, SEPSIS AND CHRONIC ILLNESSES REPRESENTED BY PULMONARY ARTERIAL HYPERTENSION AND INTERSTITIAL LUNG DISEASE. THE STRUCTURAL INTEGRITY OF ENDOTHELIAL BARRIER IS MAINTAINED BY CYTOSKELETON ELEMENTS, CELL-SUBSTRATE FOCAL ADHESION AND ADHESIVE CELL JUNCTIONS. AGONIST-MEDIATED CHANGES IN ENDOTHELIAL PERMEABILITY ARE DIRECTLY ASSOCIATED WITH REORGANIZATION OF ACTOMYOSIN CYTOSKELETON LEADING TO CELL CONTRACTION AND OPENING OF INTERCELLULAR GAPS OR ENHANCEMENT OF CORTICAL ACTIN CYTOSKELETON ASSOCIATED WITH STRENGTHENING OF ENDOTHELIAL BARRIER. THE ROLE OF ACTIN CYTOSKELETON REMODELING IN ENDOTHELIAL BARRIER REGULATION HAS TAKEN THE CENTRAL STAGE, BUT THE IMPACT OF MICROTUBULES IN THIS PROCESS REMAINS LESS EXPLORED AND UNDER-APPRECIATED. THIS REVIEW WILL SUMMARIZE THE CURRENT KNOWLEDGE ON THE CROSSTALK BETWEEN MICROTUBULES DYNAMICS AND ACTIN CYTOSKELETON REMODELING, DESCRIBE THE SIGNALING MECHANISMS MEDIATING THIS CROSSTALK, DISCUSS EPIGENETIC REGULATION OF MICROTUBULES STABILITY AND ITS NEXUS WITH ENDOTHELIAL BARRIER MAINTENANCE, AND OVERVIEW A ROLE OF MICROTUBULES IN TARGETED DELIVERY OF SIGNALING MOLECULES REGULATING ENDOTHELIAL PERMEABILITY AND INFLAMMATION. 2021 2 4116 39 MECHANISMS OF AIRWAY EPITHELIAL INJURY AND ABNORMAL REPAIR IN ASTHMA AND COPD. THE AIRWAY EPITHELIUM COMPRISES OF DIFFERENT CELL TYPES AND ACTS AS A PHYSICAL BARRIER PREVENTING PATHOGENS, INCLUDING INHALED PARTICLES AND MICROBES, FROM ENTERING THE LUNGS. GOBLET CELLS AND SUBMUCOSAL GLANDS PRODUCE MUCUS THAT TRAPS PATHOGENS, WHICH ARE EXPELLED FROM THE RESPIRATORY TRACT BY CILIATED CELLS. BASAL CELLS ACT AS PROGENITOR CELLS, DIFFERENTIATING INTO DIFFERENT EPITHELIAL CELL TYPES, TO MAINTAIN HOMEOSTASIS FOLLOWING INJURY. ADHERENS AND TIGHT JUNCTIONS BETWEEN CELLS MAINTAIN THE EPITHELIAL BARRIER FUNCTION AND REGULATE THE MOVEMENT OF MOLECULES ACROSS IT. IN THIS REVIEW WE DISCUSS HOW ABNORMAL EPITHELIAL STRUCTURE AND FUNCTION, CAUSED BY CHRONIC INJURY AND ABNORMAL REPAIR, DRIVES AIRWAY DISEASE AND SPECIFICALLY ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). IN BOTH DISEASES, INHALED ALLERGENS, POLLUTANTS AND MICROBES DISRUPT JUNCTIONAL COMPLEXES AND PROMOTE CELL DEATH, IMPAIRING THE BARRIER FUNCTION AND LEADING TO INCREASED PENETRATION OF PATHOGENS AND A CONSTANT AIRWAY IMMUNE RESPONSE. IN ASTHMA, THE INFLAMMATORY RESPONSE PRECIPITATES THE EPITHELIAL INJURY AND DRIVES ABNORMAL BASAL CELL DIFFERENTIATION. THIS LEADS TO REDUCED CILIATED CELLS, GOBLET CELL HYPERPLASIA AND INCREASED EPITHELIAL MESENCHYMAL TRANSITION, WHICH CONTRIBUTE TO IMPAIRED MUCOCILIARY CLEARANCE AND AIRWAY REMODELLING. IN COPD, CHRONIC OXIDATIVE STRESS AND INFLAMMATION TRIGGER PREMATURE EPITHELIAL CELL SENESCENCE, WHICH CONTRIBUTES TO LOSS OF EPITHELIAL INTEGRITY AND AIRWAY INFLAMMATION AND REMODELLING. INCREASED NUMBERS OF BASAL CELLS SHOWING DEREGULATED DIFFERENTIATION, CONTRIBUTES TO CILIARY DYSFUNCTION AND MUCOUS HYPERPRODUCTION IN COPD AIRWAYS. DEFECTIVE ANTIOXIDANT, ANTIVIRAL AND DAMAGE REPAIR MECHANISMS, POSSIBLY DUE TO GENETIC OR EPIGENETIC FACTORS, MAY CONFER SUSCEPTIBILITY TO AIRWAY EPITHELIAL DYSFUNCTION IN THESE DISEASES. THE CURRENT EVIDENCE SUGGESTS THAT A CONSTANT CYCLE OF INJURY AND ABNORMAL REPAIR OF THE EPITHELIUM DRIVES CHRONIC AIRWAY INFLAMMATION AND REMODELLING IN ASTHMA AND COPD. MECHANISTIC UNDERSTANDING OF INJURY SUSCEPTIBILITY AND DAMAGE RESPONSE MAY LEAD TO IMPROVED THERAPIES FOR THESE DISEASES. 2023 3 1395 34 DIET AND MICROBIOME IN THE BEGINNING OF THE SEQUENCE OF GUT INFLAMMATION. INFLAMMATORY BOWEL DISEASE (IBD) IS A CHRONIC INFLAMMATORY CONDITION OF THE GASTROINTESTINAL TRACT DUE, AT LEAST PARTIALLY, TO AN ABERRANT AND EXCESSIVE MUCOSAL IMMUNE RESPONSE TO GUT BACTERIA IN GENETICALLY-PREDISPOSED INDIVIDUALS UNDER CERTAIN ENVIRONMENTAL FACTORS. THE INCIDENCE OF IBD IS RISING IN WESTERN AND NEWLY INDUSTRIALIZED COUNTRIES, PARALLELING THE INCREASE OF WESTERNIZED DIETARY PATTERNS, THROUGH NEW ANTIGENS, EPITHELIAL FUNCTION AND PERMEABILITY, EPIGENETIC MECHANISMS (E.G., DNA METHYLATION), AND ALTERATION OF THE GUT MICROBIOME. ALTERATION IN THE COMPOSITION AND FUNCTIONALITY OF THE GUT MICROBIOME (INCLUDING BACTERIA, VIRUSES AND FUNGI) SEEMS TO BE A NUCLEAR PATHOGENIC FACTOR. THE MICROBIOME ITSELF IS DYNAMIC, AND THE CHANGES IN FOOD QUALITY, DIETARY HABITS, LIVING CONDITIONS AND HYGIENE OF THESE WESTERN SOCIETIES, COULD INTERACT IN A COMPLEX MANNER AS MODULATORS OF DYSBIOSIS, THEREBY INFLUENCING THE ACTIVATION OF IMMUNE CELLS' PROMOTING INFLAMMATION. THE MICROBIOME PRODUCES DIVERSE SMALL MOLECULES VIA SEVERAL METABOLIC WAYS, WITH THE FIBER-DERIVED SHORT-CHAIN FATTY ACIDS (I.E., BUTYRATE) AS MAIN ELEMENTS AND HAVING ANTI-INFLAMMATORY EFFECTS. THESE METABOLITES AND SOME MICRONUTRIENTS OF THE DIET (I.E., VITAMINS, FOLIC ACID, BETA CAROTENE AND TRACE ELEMENTS) ARE REGULATORS OF INNATE AND ADAPTIVE INTESTINAL IMMUNE HOMEOSTASIS. AN EXCESSIVE AND UNHEALTHY CONSUMPTION OF SUGAR, ANIMAL FAT AND A LOW-VEGETABLE AND -FIBER DIET ARE RISK FACTORS FOR IBD APPEARANCE. FURTHERMORE, METABOLISM OF NUTRIENTS IN INTESTINAL EPITHELIUM AND IN GUT MICROBIOTA IS ALTERED BY INFLAMMATION, CHANGING THE DEMAND FOR NUTRIENTS NEEDED FOR HOMEOSTASIS. THIS ROLE OF FOOD AND A REDUCED GUT MICROBIAL DIVERSITY IN CAUSING IBD MIGHT ALSO HAVE A PROPHYLACTIC OR THERAPEUTIC ROLE FOR IBD. THE RELATIONSHIP BETWEEN DIETARY INTAKE, SYMPTOMS, AND BOWEL INFLAMMATION COULD LEAD TO DIETARY AND LIFESTYLE RECOMMENDATIONS, INCLUDING DIETS WITH ABUNDANT FRUITS, VEGETABLES, OLIVE OIL AND OILY FISH, WHICH HAVE ANTI-INFLAMMATORY EFFECTS AND COULD PREVENT DYSBIOSIS AND IBD. DIETARY MODULATION AND APPROPRIATE EXCLUSION DIETS MIGHT BE A NEW COMPLEMENTARY MANAGEMENT FOR TREATMENT AT DISEASE FLARES AND IN REFRACTORY PATIENTS, EVEN REDUCING COMPLICATIONS, HOSPITALIZATIONS AND SURGERY, THROUGH MODIFYING THE LUMINAL INTESTINAL ENVIRONMENT. 2021 4 2617 35 EPIGENOME TARGETING BY PROBIOTIC METABOLITES. BACKGROUND: THE INTESTINAL MICROBIOTA PLAYS AN IMPORTANT ROLE IN IMMUNE DEVELOPMENT AND HOMEOSTASIS. A DISTURBED MICROBIOTA DURING EARLY INFANCY IS ASSOCIATED WITH AN INCREASED RISK OF DEVELOPING INFLAMMATORY AND ALLERGIC DISEASES LATER IN LIFE. THE MECHANISMS UNDERLYING THESE EFFECTS ARE POORLY UNDERSTOOD BUT ARE LIKELY TO INVOLVE ALTERATIONS IN MICROBIAL PRODUCTION OF FERMENTATION-DERIVED METABOLITES, WHICH HAVE POTENT IMMUNE MODULATING PROPERTIES AND ARE REQUIRED FOR MAINTENANCE OF HEALTHY MUCOSAL IMMUNE RESPONSES. PROBIOTICS ARE BENEFICIAL BACTERIA THAT HAVE THE CAPACITY TO ALTER THE COMPOSITION OF BACTERIAL SPECIES IN THE INTESTINE THAT CAN IN TURN INFLUENCE THE PRODUCTION OF FERMENTATION-DERIVED METABOLITES. PRINCIPAL AMONG THESE METABOLITES ARE THE SHORT-CHAIN FATTY ACIDS BUTYRATE AND ACETATE THAT HAVE POTENT ANTI-INFLAMMATORY ACTIVITIES IMPORTANT IN REGULATING IMMUNE FUNCTION AT THE INTESTINAL MUCOSAL SURFACE. THEREFORE STRATEGIES AIMED AT RESTORING THE MICROBIOTA PROFILE MAY BE EFFECTIVE IN THE PREVENTION OR TREATMENT OF ALLERGIC AND INFLAMMATORY DISEASES. PRESENTATION OF THE HYPOTHESIS: PROBIOTIC BACTERIA HAVE DIVERSE EFFECTS INCLUDING ALTERING MICROBIOTA COMPOSITION, REGULATING EPITHELIAL CELL BARRIER FUNCTION AND MODULATING OF IMMUNE RESPONSES. THE PRECISE MOLECULAR MECHANISMS MEDIATING THESE PROBIOTIC EFFECTS ARE NOT WELL UNDERSTOOD. SHORT-CHAIN FATTY ACIDS SUCH AS BUTYRATE ARE A CLASS OF HISTONE DEACETYLASE INHIBITORS IMPORTANT IN THE EPIGENETIC CONTROL OF HOST CELL RESPONSES. IT IS HYPOTHESIZED THAT THE BIOLOGICAL FUNCTION OF PROBIOTICS MAY BE A RESULT OF EPIGENETIC MODIFICATIONS THAT MAY EXPLAIN THE WIDE RANGE OF EFFECTS OBSERVED. STUDIES DELINEATING THE EFFECTS OF PROBIOTICS ON SHORT-CHAIN FATTY ACID PRODUCTION AND THE EPIGENETIC ACTIONS OF SHORT-CHAIN FATTY ACIDS WILL ASSIST IN UNDERSTANDING THE ASSOCIATION BETWEEN MICROBIOTA AND ALLERGIC OR AUTOIMMUNE DISORDERS. TESTING THE HYPOTHESIS: WE PROPOSE THAT TREATMENT WITH SPECIFIC PROBIOTIC BACTERIA UNDER IN VIVO CONDITIONS WOULD OFFER THE IDEAL CONDITIONS TO EXAMINE THE MICROBIOLOGICAL, IMMUNOLOGICAL AND EPIGENETIC MECHANISMS OF ACTION. ADVANCES IN EPIGENETIC TECHNOLOGY NOW ALLOW INVESTIGATORS TO BETTER UNDERSTAND THE COMPLEX BIOLOGICAL PROPERTIES OF PROBIOTICS AND THEIR METABOLITES. IMPLICATIONS OF THE HYPOTHESIS: DETERMINING THE PRECISE MECHANISMS OF PROBIOTIC ACTION WILL LEAD TO MORE SPECIFIC AND EFFICACIOUS THERAPEUTIC STRATEGIES IN THE PREVENTION OR TREATMENT OF CHRONIC INFLAMMATORY CONDITIONS. 2010 5 375 20 AN ENERGETIC VIEW OF STRESS: FOCUS ON MITOCHONDRIA. ENERGY IS REQUIRED TO SUSTAIN LIFE AND ENABLE STRESS ADAPTATION. AT THE CELLULAR LEVEL, ENERGY IS LARGELY DERIVED FROM MITOCHONDRIA - UNIQUE MULTIFUNCTIONAL ORGANELLES WITH THEIR OWN GENOME. FOUR MAIN ELEMENTS CONNECT MITOCHONDRIA TO STRESS: (1) ENERGY IS REQUIRED AT THE MOLECULAR, (EPI)GENETIC, CELLULAR, ORGANELLAR, AND SYSTEMIC LEVELS TO SUSTAIN COMPONENTS OF STRESS RESPONSES; (2) GLUCOCORTICOIDS AND OTHER STEROID HORMONES ARE PRODUCED AND METABOLIZED BY MITOCHONDRIA; (3) RECIPROCALLY, MITOCHONDRIA RESPOND TO NEUROENDOCRINE AND METABOLIC STRESS MEDIATORS; AND (4) EXPERIMENTALLY MANIPULATING MITOCHONDRIAL FUNCTIONS ALTERS PHYSIOLOGICAL AND BEHAVIORAL RESPONSES TO PSYCHOLOGICAL STRESS. THUS, MITOCHONDRIA ARE ENDOCRINE ORGANELLES THAT PROVIDE BOTH THE ENERGY AND SIGNALS THAT ENABLE AND DIRECT STRESS ADAPTATION. NEURAL CIRCUITS REGULATING SOCIAL BEHAVIOR - AS WELL AS PSYCHOPATHOLOGICAL PROCESSES - ARE ALSO INFLUENCED BY MITOCHONDRIAL ENERGETICS. AN INTEGRATIVE VIEW OF STRESS AS AN ENERGY-DRIVEN PROCESS OPENS NEW OPPORTUNITIES TO STUDY MECHANISMS OF ADAPTATION AND REGULATION ACROSS THE LIFESPAN. 2018 6 2342 28 EPIGENETIC REGULATION OF MACROPHAGE POLARIZATION AND FUNCTION. MACROPHAGE POLARIZATION REFERS TO DEVELOPMENT OF A SPECIFIC PHENOTYPE IMPORTANT FOR TISSUE HOMEOSTASIS OR HOST DEFENSE IN RESPONSE TO ENVIRONMENTAL CUES. ENVIRONMENTAL FACTORS THAT INDUCE MACROPHAGE POLARIZATION INCLUDE CYTOKINES AND MICROBIAL FACTORS PRODUCED BY PATHOGENS OR COMMENSAL MICROBIOTA. SIGNALING PATHWAYS UTILIZED BY THESE POLARIZING FACTORS HAVE BEEN WELL CHARACTERIZED, BUT IT IS LESS CLEAR HOW SIGNALS ARE CONVERTED INTO COMPLEX AND SUSTAINED PATTERNS OF GENE EXPRESSION, AND HOW MACROPHAGES ARE REPROGRAMMED DURING POLARIZATION TO ALTER THEIR RESPONSES TO SUBSEQUENT ENVIRONMENTAL CHALLENGES. EMERGING EVIDENCE, REVIEWED HERE, SUGGESTS AN IMPORTANT ROLE FOR EPIGENETIC MECHANISMS IN MODULATING AND TRANSMITTING SIGNALS DURING MACROPHAGE POLARIZATION AND REPROGRAMMING. DEEPER UNDERSTANDING OF EPIGENETIC REGULATION OF MACROPHAGE PHENOTYPE WILL ENABLE DEVELOPMENT OF GENE-SPECIFIC THERAPEUTIC APPROACHES TO ENHANCE HOST DEFENSE WHILE PRESERVING TISSUE INTEGRITY AND PREVENTING CHRONIC INFLAMMATORY DISEASES. 2013 7 3585 30 IMPACT OF THE EXPOSOME ON THE EPIGENOME IN INFLAMMATORY BOWEL DISEASE PATIENTS AND ANIMAL MODELS. INFLAMMATORY BOWEL DISEASES (IBD) ARE CHRONIC INFLAMMATORY DISORDERS OF THE GASTROINTESTINAL TRACT THAT ENCOMPASS TWO MAIN PHENOTYPES, NAMELY CROHN'S DISEASE AND ULCERATIVE COLITIS. THESE CONDITIONS OCCUR IN GENETICALLY PREDISPOSED INDIVIDUALS IN RESPONSE TO ENVIRONMENTAL FACTORS. EPIGENETICS, ACTING BY DNA METHYLATION, POST-TRANSLATIONAL HISTONES MODIFICATIONS OR BY NON-CODING RNAS, COULD EXPLAIN HOW THE EXPOSOME (OR ALL ENVIRONMENTAL INFLUENCES OVER THE LIFE COURSE, FROM CONCEPTION TO DEATH) COULD INFLUENCE THE GENE EXPRESSION TO CONTRIBUTE TO INTESTINAL INFLAMMATION. WE PERFORMED A SCOPING SEARCH USING MEDLINE TO IDENTIFY ALL THE ELEMENTS OF THE EXPOSOME THAT MAY PLAY A ROLE IN INTESTINAL INFLAMMATION THROUGH EPIGENETIC MODIFICATIONS, AS WELL AS THE UNDERLYING MECHANISMS. THE ENVIRONMENTAL FACTORS EPIGENETICALLY INFLUENCING THE OCCURRENCE OF INTESTINAL INFLAMMATION ARE THE MATERNAL LIFESTYLE (MAINLY DIET, THE OCCURRENCE OF INFECTION DURING PREGNANCY AND SMOKING); BREASTFEEDING; MICROBIOTA; DIET (INCLUDING A LOW-FIBER DIET, HIGH-FAT DIET AND DEFICIENCY IN MICRONUTRIENTS); SMOKING HABITS, VITAMIN D AND DRUGS (E.G., IBD TREATMENTS, ANTIBIOTICS AND PROBIOTICS). INFLUENCED BY BOTH MICROBIOTA AND DIET, SHORT-CHAIN FATTY ACIDS ARE GUT MICROBIOTA-DERIVED METABOLITES RESULTING FROM THE ANAEROBIC FERMENTATION OF NON-DIGESTIBLE DIETARY FIBERS, PLAYING AN EPIGENETICALLY MEDIATED ROLE IN THE INTEGRITY OF THE EPITHELIAL BARRIER AND IN THE DEFENSE AGAINST INVADING MICROORGANISMS. ALTHOUGH THE IMPACT OF SOME ENVIRONMENTAL FACTORS HAS BEEN IDENTIFIED, THE EXPOSOME-INDUCED EPIMUTATIONS IN IBD REMAIN A LARGELY UNDEREXPLORED FIELD. HOW THESE ENVIRONMENTAL EXPOSURES INDUCE EPIGENETIC MODIFICATIONS (IN TERMS OF DURATION, FREQUENCY AND THE TIMING AT WHICH THEY OCCUR) AND HOW OTHER ENVIRONMENTAL FACTORS ASSOCIATED WITH IBD MODULATE EPIGENETICS DESERVE TO BE FURTHER INVESTIGATED. 2022 8 6374 31 THE ROLE OF MITOCHONDRIA IN MYOCARDIAL DAMAGE CAUSED BY ENERGY METABOLISM DISORDERS: FROM MECHANISMS TO THERAPEUTICS. MYOCARDIAL DAMAGE IS THE MOST SERIOUS PATHOLOGICAL CONSEQUENCE OF CARDIOVASCULAR DISEASES AND AN IMPORTANT REASON FOR THEIR HIGH MORTALITY. IN RECENT YEARS, BECAUSE OF THE HIGH PREVALENCE OF SYSTEMIC ENERGY METABOLISM DISORDERS (E.G., OBESITY, DIABETES MELLITUS, AND METABOLIC SYNDROME), COMPLICATIONS OF MYOCARDIAL DAMAGE CAUSED BY THESE DISORDERS HAVE ATTRACTED WIDESPREAD ATTENTION. ENERGY METABOLISM DISORDERS ARE INDEPENDENT OF TRADITIONAL INJURY-RELATED RISK FACTORS, SUCH AS ISCHEMIA, HYPOXIA, TRAUMA, AND INFECTION. AN IMBALANCE OF MYOCARDIAL METABOLIC FLEXIBILITY AND MYOCARDIAL ENERGY DEPLETION ARE USUALLY THE INITIAL CHANGES OF MYOCARDIAL INJURY CAUSED BY ENERGY METABOLISM DISORDERS, AND ABNORMAL MORPHOLOGY AND FUNCTIONAL DESTRUCTION OF THE MITOCHONDRIA ARE THEIR IMPORTANT FEATURES. SPECIFICALLY, MITOCHONDRIA ARE THE CENTERS OF ENERGY METABOLISM, AND RECENT EVIDENCE HAS SHOWN THAT DECREASED MITOCHONDRIAL FUNCTION, CAUSED BY AN IMBALANCE IN MITOCHONDRIAL QUALITY CONTROL, MAY PLAY A KEY ROLE IN MYOCARDIAL INJURY CAUSED BY ENERGY METABOLISM DISORDERS. UNDER CHRONIC ENERGY STRESS, MITOCHONDRIA UNDERGO PATHOLOGICAL FISSION, WHILE MITOPHAGY, MITOCHONDRIAL FUSION, AND BIOGENESIS ARE INHIBITED, AND MITOCHONDRIAL PROTEIN BALANCE AND TRANSFER ARE DISTURBED, RESULTING IN THE ACCUMULATION OF NONFUNCTIONAL AND DAMAGED MITOCHONDRIA. CONSEQUENTLY, DAMAGED MITOCHONDRIA LEAD TO MYOCARDIAL ENERGY DEPLETION AND THE ACCUMULATION OF LARGE AMOUNTS OF REACTIVE OXYGEN SPECIES, FURTHER AGGRAVATING THE IMBALANCE IN MITOCHONDRIAL QUALITY CONTROL AND FORMING A VICIOUS CYCLE. IN ADDITION, IMPAIRED MITOCHONDRIA COORDINATE CALCIUM HOMEOSTASIS IMBALANCE, AND EPIGENETIC ALTERATIONS PARTICIPATE IN THE PATHOGENESIS OF MYOCARDIAL DAMAGE. THESE PATHOLOGICAL CHANGES INDUCE RAPID PROGRESSION OF MYOCARDIAL DAMAGE, EVENTUALLY LEADING TO HEART FAILURE OR SUDDEN CARDIAC DEATH. TO INTERVENE MORE SPECIFICALLY IN THE MYOCARDIAL DAMAGE CAUSED BY METABOLIC DISORDERS, WE NEED TO UNDERSTAND THE SPECIFIC ROLE OF MITOCHONDRIA IN THIS CONTEXT IN DETAIL. ACCORDINGLY, PROMISING THERAPEUTIC STRATEGIES HAVE BEEN PROPOSED. WE ALSO SUMMARIZE THE EXISTING THERAPEUTIC STRATEGIES TO PROVIDE A REFERENCE FOR CLINICAL TREATMENT AND DEVELOPING NEW THERAPIES. 2023 9 4379 32 MITOCHONDRIAL DYSFUNCTION AND AGING: INSIGHTS FROM THE ANALYSIS OF EXTRACELLULAR VESICLES. THE PROGRESSIVE DECLINE OF CELL FUNCTION AND INTEGRITY, MANIFESTING CLINICALLY AS INCREASED VULNERABILITY TO ADVERSE OUTCOMES AND DEATH, IS CORE TO BIOLOGICAL AGING. MITOCHONDRIAL DYSFUNCTION, OXIDATIVE STRESS, ALTERED INTERCELLULAR COMMUNICATION (INCLUDING CHRONIC LOW-GRADE INFLAMMATION), GENOMIC INSTABILITY, TELOMERE ATTRITION, LOSS OF PROTEOSTASIS, ALTERED NUTRIENT SENSING, EPIGENETIC ALTERATIONS, AND STEM CELL EXHAUSTION HAVE BEEN PROPOSED AS HALLMARKS OF AGING. THESE "AGING PILLARS" ARE NOT MUTUALLY EXCLUSIVE, MAKING THE MATTER INTRICATE AND LEAVING NUMEROUS UNANSWERED QUESTIONS. THE CHARACTERIZATION OF CIRCULATING EXTRACELLULAR VESICLES (EVS) HAS RECENTLY ALLOWED SPECIFIC SECRETORY PHENOTYPES ASSOCIATED WITH AGING TO BE IDENTIFIED. AS SUCH, EVS MAY SERVE AS NOVEL BIOMARKERS FOR CAPTURING THE COMPLEXITY OF AGING. BESIDES THE MITOCHONDRIAL(-)LYSOSOMAL AXIS, EV TRAFFICKING HAS BEEN PROPOSED AS AN ADDITIONAL LAYER IN MITOCHONDRIAL QUALITY CONTROL. INDEED, DISRUPTION OF THE MITOCHONDRIAL(-)LYSOSOMAL AXIS COUPLED WITH ABNORMAL EV SECRETION MAY PLAY A ROLE IN THE PATHOGENESIS OF AGING AND SEVERAL DISEASE CONDITIONS. HERE, WE DISCUSS (1) THE MECHANISMS OF EV GENERATION; (2) THE RELATIONSHIP BETWEEN THE MITOCHONDRIAL(-)LYSOSOMAL AXIS AND EV TRAFFICKING IN THE SETTING OF MITOCHONDRIAL QUALITY CONTROL; AND (3) THE PROSPECT OF USING EVS AS AGING BIOMARKERS AND AS DELIVERY SYSTEMS FOR THERAPEUTICS AGAINST AGE-RELATED CONDITIONS. 2019 10 4082 27 MATERNAL MODIFIERS OF THE INFANT GUT MICROBIOTA: METABOLIC CONSEQUENCES. TRANSMISSION OF METABOLIC DISEASES FROM MOTHER TO CHILD IS MULTIFACTORIAL AND INCLUDES GENETIC, EPIGENETIC AND ENVIRONMENTAL INFLUENCES. EVIDENCE IN RODENTS, HUMANS AND NON-HUMAN PRIMATES SUPPORT THE SCIENTIFIC PREMISE THAT EXPOSURE TO MATERNAL OBESITY OR HIGH-FAT DIET DURING PREGNANCY CREATES A LONG-LASTING METABOLIC SIGNATURE ON THE INFANT INNATE IMMUNE SYSTEM AND THE JUVENILE MICROBIOTA, WHICH PREDISPOSES THE OFFSPRING TO OBESITY AND METABOLIC DISEASES. IN NEONATES, GASTROINTESTINAL MICROBES INTRODUCED THROUGH THE MOTHER ARE NOTED FOR THEIR ABILITY TO SERVE AS DIRECT INDUCERS/REGULATORS OF THE INFANT IMMUNE SYSTEM. NEONATES HAVE A LIMITED CAPACITY TO INITIATE AN IMMUNE RESPONSE. THUS, DISRUPTION OF MICROBIAL COLONIZATION DURING THE EARLY NEONATAL PERIOD RESULTS IN DISRUPTED POSTNATAL IMMUNE RESPONSES THAT HIGHLIGHT THE NEONATAL PERIOD AS A CRITICAL DEVELOPMENTAL WINDOW. ALTHOUGH THE MECHANISMS ARE POORLY UNDERSTOOD, INCREASING EVIDENCE SUGGESTS THAT MATERNAL OBESITY OR POOR DIET INFLUENCES THE DEVELOPMENT AND MODULATION OF THE INFANT LIVER AND OTHER END ORGANS THROUGH DIRECT COMMUNICATION VIA THE PORTAL SYSTEM, METABOLITE PRODUCTION, ALTERATIONS IN GUT BARRIER INTEGRITY AND THE HEMATOPOIETIC IMMUNE CELL AXIS. THIS REVIEW WILL FOCUS ON HOW MATERNAL OBESITY AND DIETARY INTAKE INFLUENCE THE COMPOSITION OF THE INFANT GUT MICROBIOTA AND HOW AN IMBALANCE OR MALADAPTATION IN THE MICROBIOTA, INCLUDING CHANGES IN EARLY PIONEERING MICROBES, MIGHT CONTRIBUTE TO THE PROGRAMMING OF OFFSPRING METABOLISM WITH SPECIAL EMPHASIS ON MECHANISMS THAT PROMOTE CHRONIC INFLAMMATION IN THE LIVER. COMPREHENSION OF THESE PATHWAYS AND MECHANISMS WILL ELUCIDATE OUR UNDERSTANDING OF DEVELOPMENTAL PROGRAMMING AND MAY EXPAND THE AVENUE OF OPPORTUNITIES FOR NOVEL THERAPEUTICS. 2017 11 6169 28 THE GUT MICROBIOTA AND HEALTHY AGING: A MINI-REVIEW. THE GUT MICROBIOTA SHOWS A WIDE INTER-INDIVIDUAL VARIATION, BUT ITS WITHIN-INDIVIDUAL VARIATION IS RELATIVELY STABLE OVER TIME. A FUNCTIONAL CORE MICROBIOME, PROVIDED BY ABUNDANT BACTERIAL TAXA, SEEMS TO BE COMMON TO VARIOUS HUMAN HOSTS REGARDLESS OF THEIR GENDER, GEOGRAPHIC LOCATION, AND AGE. WITH ADVANCING CHRONOLOGICAL AGE, THE GUT MICROBIOTA BECOMES MORE DIVERSE AND VARIABLE. HOWEVER, WHEN MEASURES OF BIOLOGICAL AGE ARE USED WITH ADJUSTMENT FOR CHRONOLOGICAL AGE, OVERALL RICHNESS DECREASES, WHILE A CERTAIN GROUP OF BACTERIA ASSOCIATED WITH FRAILTY INCREASES. THIS HIGHLIGHTS THE IMPORTANCE OF CONSIDERING BIOLOGICAL OR FUNCTIONAL MEASURES OF AGING. STUDIES USING MODEL ORGANISMS INDICATE THAT AGE-RELATED GUT DYSBIOSIS MAY CONTRIBUTE TO UNHEALTHY AGING AND REDUCED LONGEVITY. THE GUT MICROBIOME DEPENDS ON THE HOST NUTRIENT SIGNALING PATHWAYS FOR ITS BENEFICIAL EFFECTS ON HOST HEALTH AND LIFESPAN, AND GUT DYSBIOSIS DISRUPTING THE INTERDEPENDENCE MAY DIMINISH THE BENEFICIAL EFFECTS OR EVEN HAVE REVERSE EFFECTS. GUT DYSBIOSIS CAN TRIGGER THE INNATE IMMUNE RESPONSE AND CHRONIC LOW-GRADE INFLAMMATION, LEADING TO MANY AGE-RELATED DEGENERATIVE PATHOLOGIES AND UNHEALTHY AGING. THE GUT MICROBIOTA COMMUNICATES WITH THE HOST THROUGH VARIOUS BIOMOLECULES, NUTRIENT SIGNALING-INDEPENDENT PATHWAYS, AND EPIGENETIC MECHANISMS. DISTURBANCE OF THESE COMMUNICATIONS BY AGE-RELATED GUT DYSBIOSIS CAN AFFECT THE HOST HEALTH AND LIFESPAN. THIS MAY EXPLAIN THE IMPACT OF THE GUT MICROBIOME ON HEALTH AND AGING. 2018 12 5631 28 SENESCENCE-INFLAMMATORY REGULATION OF REPARATIVE CELLULAR REPROGRAMMING IN AGING AND CANCER. THE INABILITY OF ADULT TISSUES TO TRANSITORILY GENERATE CELLS WITH FUNCTIONAL STEM CELL-LIKE PROPERTIES IS A MAJOR OBSTACLE TO TISSUE SELF-REPAIR. NUCLEAR REPROGRAMMING-LIKE PHENOMENA THAT INDUCE A TRANSIENT ACQUISITION OF EPIGENETIC PLASTICITY AND PHENOTYPE MALLEABILITY MAY CONSTITUTE A REPARATIVE ROUTE THROUGH WHICH HUMAN TISSUES RESPOND TO INJURY, STRESS, AND DISEASE. HOWEVER, TISSUE REJUVENATION SHOULD INVOLVE NOT ONLY THE TRANSIENT EPIGENETIC REPROGRAMMING OF DIFFERENTIATED CELLS, BUT ALSO THE COMMITTED RE-ACQUISITION OF THE ORIGINAL OR ALTERNATIVE COMMITTED CELL FATE. CHRONIC OR UNRESTRAINED EPIGENETIC PLASTICITY WOULD DRIVE AGING PHENOTYPES BY IMPAIRING THE REPAIR OR THE REPLACEMENT OF DAMAGED CELLS; SUCH UNCONTROLLED PHENOMENA OF IN VIVO REPROGRAMMING MIGHT ALSO GENERATE CANCER-LIKE CELLULAR STATES. WE HEREIN PROPOSE THAT THE ABILITY OF SENESCENCE-ASSOCIATED INFLAMMATORY SIGNALING TO REGULATE IN VIVO REPROGRAMMING CYCLES OF TISSUE REPAIR OUTLINES A THRESHOLD MODEL OF AGING AND CANCER. THE DEGREE OF SENESCENCE/INFLAMMATION-ASSOCIATED DEVIATION FROM THE HOMEOSTATIC STATE MAY DELINEATE A TYPE OF THRESHOLDING ALGORITHM DISTINGUISHING BENEFICIAL FROM DELETERIOUS EFFECTS OF IN VIVO REPROGRAMMING. FIRST, TRANSIENT ACTIVATION OF NF-KAPPAB-RELATED INNATE IMMUNITY AND SENESCENCE-ASSOCIATED INFLAMMATORY COMPONENTS (E.G., IL-6) MIGHT FACILITATE REPARATIVE CELLULAR REPROGRAMMING IN RESPONSE TO ACUTE INFLAMMATORY EVENTS. SECOND, PARA-INFLAMMATION SWITCHES MIGHT PROMOTE LONG-LASTING BUT REVERSIBLE REFRACTORINESS TO REPARATIVE CELLULAR REPROGRAMMING. THIRD, CHRONIC SENESCENCE-ASSOCIATED INFLAMMATORY SIGNALING MIGHT LOCK CELLS IN HIGHLY PLASTIC EPIGENETIC STATES DISABLED FOR REPARATIVE DIFFERENTIATION. THE CONSIDERATION OF A CELLULAR REPROGRAMMING-CENTERED VIEW OF EPIGENETIC PLASTICITY AS A FUNDAMENTAL ELEMENT OF A TISSUE'S CAPACITY TO UNDERGO SUCCESSFUL REPAIR, AGING DEGENERATION OR MALIGNANT TRANSFORMATION SHOULD PROVIDE CHALLENGING STOCHASTIC INSIGHTS INTO THE CURRENT DETERMINISTIC GENETIC PARADIGM FOR MOST CHRONIC DISEASES, THEREBY INCREASING THE SPECTRUM OF THERAPEUTIC APPROACHES FOR PHYSIOLOGICAL AGING AND CANCER. 2017 13 601 23 BETA-GLUCAN "TRAINED IMMUNITY" IMMUNOMODULATORY PROPERTIES POTENTIATE TISSUE WOUND MANAGEMENT AND ACCELERATE FITNESS RECOVER. INTRODUCTION: IT IS WELL ESTABLISHED THAT MODERATE PHYSICAL ACTIVITY CAN IMPROVE THE IMMUNE STATUS, RATHER EXCESS OR HIGH-INTENSITY PHYSICAL EXERCISE CAN CAUSE DAMAGE TO THE IMMUNE SYSTEM. IN ADDITION, MUSCLE INJURIES RESULTING FROM INCREASED FREQUENCY AND INTENSITY OF EXERCISES COMPROMISE INNATE IMMUNE ACTIVITY AND MAY DECREASE TISSUE REGENERATION. THUS, BETA-GLUCANS, A NATURAL COMPOUND, MAY REPRESENT AN IMPORTANT SUBSTANCE WITH STRONG IMMUNOMODULATORY PROPERTIES ACTING AS AN IMMUNOSTIMULANT THERAPY KNOWN AS "TRAINED IMMUNITY". THIS IMMUNE STIMULATING THERAPEUTIC IS AN IMMUNOLOGICAL MEMORY PHENOMENON LINKED TO THE INNATE IMMUNE SYSTEM, TRIGGERING CELLULAR CHANGES AT EPIGENETIC, TRANSCRIPTIONAL, AND FUNCTIONAL LEVELS, TO REGULATE THE IMMUNE SYSTEM AND RECOVER ITS HOMEOSTASIS WITH CLINICAL BENEFITS. CONCLUSION: THIS NARRATIVE REVIEW WORKS WITH THE CURRENT EVIDENCE REGARDING BETA-GLUCANS AS A POSSIBLE ALTERNATIVE THERAPY FOR WOUND HEALING AND ITS SAFETY AND EFFICACY IN THE TREATMENT OF MUSCLE INJURIES AND PHYSICAL RECOVERY INCLUDING OTHER CHRONIC CONDITIONS AND DISEASES. 2022 14 3920 23 LINKING IMMUNITY, EPIGENETICS, AND CANCER IN INFLAMMATORY BOWEL DISEASE. MOST OF WHAT IS KNOWN ABOUT THE PATHOGENESIS OF INFLAMMATORY BOWEL DISEASE (IBD) PERTAINS TO COMPLEX INTERPLAY BETWEEN HOST GENETICS, IMMUNITY, AND ENVIRONMENTAL FACTORS. EPIGENETIC MODIFICATIONS PLAY PIVOTAL ROLES IN INTESTINAL IMMUNITY AND MUCOSAL HOMEOSTASIS AS WELL AS MEDIATING GENE-ENVIRONMENT INTERACTIONS. IN THIS ARTICLE, WE PROVIDE A HISTORICAL ACCOUNT OF EPIGENETIC RESEARCH EITHER DIRECTLY RELATED OR PERTINENT TO THE PATHOGENESIS AND MANAGEMENT OF IBD. WE FURTHER COLLATE EMERGING EVIDENCE SUPPORTING ROLES FOR EPIGENETIC MECHANISMS IN RELEVANT ASPECTS OF IBD BIOLOGY, INCLUDING DEREGULATED IMMUNITY, HOST-PATHOGEN RECOGNITION AND MUCOSAL INTEGRITY. FINALLY, WE HIGHLIGHT KEY EPIGENETIC MECHANISMS THAT LINK CHRONIC INFLAMMATION TO SPECIFIC IBD COMORBIDITIES, INCLUDING COLITIS-ASSOCIATED CANCER AND DISCUSS THEIR POTENTIAL UTILITY AS NOVEL BIOMARKERS OR PHARMACOLOGIC TARGETS IN IBD THERAPY. 2014 15 4620 24 NEURO-IMMUNE DYSFUNCTION DURING BRAIN AGING: NEW INSIGHTS IN MICROGLIAL CELL REGULATION. MICROGLIA, THE RESIDENT IMMUNE CELLS OF THE BRAIN, ARE AT THE CENTER OF COMMUNICATION BETWEEN THE CENTRAL NERVOUS SYSTEM AND IMMUNE SYSTEM. WHILE THESE BRAIN-IMMUNE INTERACTIONS ARE BALANCED IN HEALTHY ADULTHOOD, THE ABILITY TO MAINTAIN HOMEOSTASIS DURING AGING IS IMPAIRED. MICROGLIA DEVELOP A LOSS OF INTEGRATED REGULATORY NETWORKS INCLUDING ABERRANT SIGNALING FROM OTHER BRAIN CELLS, IMMUNE SENSORS, AND EPIGENETIC MODIFIERS. THE LOW-GRADE CHRONIC NEUROINFLAMMATION ASSOCIATED WITH THIS DYSFUNCTIONAL ACTIVITY LIKELY CONTRIBUTES TO COGNITIVE DEFICITS AND SUSCEPTIBILITY TO AGE-RELATED PATHOLOGIES. A BETTER UNDERSTANDING OF THE UNDERLYING MECHANISMS RESPONSIBLE FOR NEURO-IMMUNE DYSREGULATION WITH AGE IS CRUCIAL FOR PROVIDING TARGETED THERAPEUTIC STRATEGIES TO SUPPORT BRAIN REPAIR AND HEALTHY AGING. 2016 16 2812 29 FIBROBLAST MEMORY IN DEVELOPMENT, HOMEOSTASIS AND DISEASE. FIBROBLASTS ARE THE MAJOR CELL POPULATION IN THE CONNECTIVE TISSUE OF MOST ORGANS, WHERE THEY ARE ESSENTIAL FOR THEIR STRUCTURAL INTEGRITY. THEY ARE BEST KNOWN FOR THEIR ROLE IN REMODELLING THE EXTRACELLULAR MATRIX, HOWEVER MORE RECENTLY THEY HAVE BEEN RECOGNISED AS A FUNCTIONALLY HIGHLY DIVERSE CELL POPULATION THAT CONSTANTLY RESPONDS AND ADAPTS TO THEIR ENVIRONMENT. BIOLOGICAL MEMORY IS THE PROCESS OF A SUSTAINED ALTERED CELLULAR STATE AND FUNCTIONS IN RESPONSE TO A TRANSIENT OR PERSISTENT ENVIRONMENTAL STIMULUS. WHILE IT IS WELL ESTABLISHED THAT FIBROBLASTS RETAIN A MEMORY OF THEIR ANATOMICAL LOCATION, HOW OTHER ENVIRONMENTAL STIMULI INFLUENCE FIBROBLAST BEHAVIOUR AND FUNCTION IS LESS CLEAR. THE ABILITY OF FIBROBLASTS TO RESPOND AND MEMORISE DIFFERENT ENVIRONMENTAL STIMULI IS ESSENTIAL FOR TISSUE DEVELOPMENT AND HOMEOSTASIS AND MAY BECOME DYSREGULATED IN CHRONIC DISEASE CONDITIONS SUCH AS FIBROSIS AND CANCER. HERE WE SUMMARISE THE FOUR EMERGING KEY AREAS OF FIBROBLAST ADAPTATION: POSITIONAL, MECHANICAL, INFLAMMATORY, AND METABOLIC MEMORY AND HIGHLIGHT THE UNDERLYING MECHANISMS AND THEIR IMPLICATIONS IN TISSUE HOMEOSTASIS AND DISEASE. 2021 17 1275 31 DAMAGE-ASSOCIATED MOLECULAR PATTERNS IN INFLAMMATORY BOWEL DISEASE: FROM BIOMARKERS TO THERAPEUTIC TARGETS. THE CHRONIC INFLAMMATORY PROCESS UNDERLYING INFLAMMATORY BOWEL DISEASE (IBD), COMPRISING CROHN'S DISEASE AND ULCERATIVE COLITIS, DERIVES FROM THE INTERPLAY OF SEVERAL COMPONENTS IN A GENETICALLY SUSCEPTIBLE HOST. THESE COMPONENTS INCLUDE ENVIRONMENTAL ELEMENTS AND GUT MICROBIOTA A DYSBIOSIS. FOR DECADES, IMMUNE ABNORMALITIES HAVE BEEN INVESTIGATED AS CRITICALLY IMPORTANT IN IBD PATHOGENESIS, AND ATTEMPTS TO DEVELOP EFFECTIVE THERAPIES HAVE PREDOMINANTLY TARGETED THE IMMUNE SYSTEM. NEVERTHELESS, IMMUNE EVENTS REPRESENT ONLY ONE OF THE CONSTITUENTS CONTRIBUTING TO IBD PATHOGENESIS WITHIN THE CONTEXT OF THE COMPLEX CELLULAR AND MOLECULAR NETWORK UNDERLYING CHRONIC INTESTINAL INFLAMMATION. THESE FACTORS NEED TO BE APPRECIATED WITHIN THE MILIEU OF NON-IMMUNE COMPONENTS. DAMAGE-ASSOCIATED MOLECULAR PATTERNS (DAMPS), WHICH ARE ESSENTIALLY ENDOGENOUS STRESS PROTEINS EXPRESSED OR RELEASED AS A RESULT OF CELL OR TISSUE DAMAGE, HAVE BEEN SHOWN TO ACT AS DIRECT PRO-INFLAMMATORY MEDIATORS. EXCESSIVE OR PERSISTENT SIGNALLING MEDIATED BY SUCH MOLECULES CAN UNDERLIE SEVERAL CHRONIC INFLAMMATORY DISORDERS, INCLUDING IBD. THE RELEASE OF ENDOGENOUS DAMPS AMPLIFIES THE INFLAMMATORY RESPONSE DRIVEN BY IMMUNE AND NON-IMMUNE CELLS AND PROMOTES EPIGENETIC REPROGRAMMING IN IBD. THE EFFECTS DETERMINE PATHOLOGIC CHANGES, WHICH MAY SUSTAIN CHRONIC INTESTINAL INFLAMMATION AND ALSO UNDERLIE SPECIFIC DISEASE PHENOTYPES. IN ADDITION TO HIGHLIGHTING THE POTENTIAL USE OF DAMPS SUCH AS CALPROTECTIN AS BIOMARKERS, RESEARCH ON DAMPS MAY REVEAL NOVEL MECHANISTIC ASSOCIATIONS IN IBD PATHOGENESIS AND IS EXPECTED TO UNCOVER PUTATIVE THERAPEUTIC TARGETS. 2018 18 3546 30 IMMUNOMODULATORY DIET IN PEDIATRIC AGE. IN THE LAST FEW DECADES, THE IMPORTANCE OF A FUNCTIONING IMMUNE SYSTEM AND HEALTH STATUS HAS BECOME MORE EVIDENT. MULTIPLE FACTORS ARE ABLE TO INFLUENCE THE DEVELOPMENT OF CHRONIC DISEASES AND DIET IS ONE OF THE MOST IMPORTANT ENVIRONMENTAL FACTORS. EVIDENCE DEMONSTRATES THAT DIETARY PATTERNS HIGH IN FAT AND LOW IN FIBER ARE ASSOCIATED WITH THE DEVELOPMENT OF NON-COMMUNICABLE DISEASES. MOREOVER, OPTIMAL NUTRITIONAL STATUS CAN MODULATE IMMUNE MATURATION AND RESPONSE TO INFLAMMATION. DURING INFLAMMATORY CONDITIONS, NUTRITIONAL DEFICIENCIES MAY OCCUR, ESTABLISHING A VICIOUS CIRCLE, CONSEQUENTLY A BALANCED NUTRITIONAL STATUS IS ESSENTIAL TO PREVENT AND COUNTERACT INFECTIONS. DIETARY DIVERSITY CAN PREVENT ALLERGIC DISEASES AND NUTRIENTS SUCH AS DHA, ARGININE, VITAMINS AND TRACE ELEMENTS HAVE AN IMPACT ON PHYSICAL BARRIERS (SUCH AS GUT MUCOSAL BARRIER AND SKIN), ON THE IMMUNE SYSTEM RESPONSE AND ON MICROBIOME MODULATION. PROTEIN DEFICIENCIES CAN COMPROMISE INNATE AND ADAPTIVE IMMUNE FUNCTIONS; ARGININE AVAILABILITY CAN AFFECT THE IMMUNE RESPONSE IN INJURED STATES AND OTHER DISEASE PROCESSES; EPA AND DHA CAN MODULATE BOTH INNATE AND ADAPTIVE IMMUNITY; PREBIOTICS HAVE A BENEFICIAL EFFECT ON THE FUNCTIONING OF THE IMMUNE SYSTEM. ZINC, COPPER, SELENIUM AND IRON ARE INVOLVED IN THE CORRECT DEVELOPMENT AND FUNCTION OF THE IMMUNE SYSTEM. VITAMINS D, E, A, B AND C HAVE A ROLE ON IMMUNE SYSTEM THROUGH DIFFERENT MECHANISMS OF ACTION. SINCE A COMPLEX INTERPLAY EXISTS BETWEEN DIET, MICROBIOME AND EPIGENETIC FACTORS WHICH DETERMINE NUTRIENT-INDUCED CHANGES ON THE IMMUNE FUNCTION, THE EFFECT OF EACH SINGLE NUTRIENT MAY BE DIFFICULT TO STUDY. WELL-DESIGNED INTERVENTION STUDIES, INVESTIGATING THE EFFECTS OF WHOLE DIETARY PATTERN, SHOULD BE PERFORMED TO CLARIFY IMPACT OF FOODS ON THE IMMUNE FUNCTION AND DISEASE RISK. 2021 19 1149 32 CONNECTING THE IMMUNE SYSTEM, SYSTEMIC CHRONIC INFLAMMATION AND THE GUT MICROBIOME: THE ROLE OF SEX. UNRESOLVED LOW GRADE SYSTEMIC INFLAMMATION REPRESENTS THE UNDERLYING PATHOLOGICAL MECHANISM DRIVING IMMUNE AND METABOLIC PATHWAYS INVOLVED IN AUTOIMMUNE DISEASES (AID). MECHANISTIC STUDIES IN ANIMAL MODELS OF AID AND OBSERVATIONAL STUDIES IN PATIENTS HAVE FOUND ALTERATIONS IN GUT MICROBIOTA COMMUNITIES AND THEIR METABOLITES, SUGGESTING A MICROBIAL CONTRIBUTION TO THE ONSET OR PROGRESSION OF AID. THE GUT MICROBIOTA AND ITS METABOLITES HAVE BEEN SHOWN TO INFLUENCE IMMUNE FUNCTIONS AND IMMUNE HOMEOSTASIS BOTH WITHIN THE GUT AND SYSTEMATICALLY. MICROBIAL DERIVED-SHORT CHAIN FATTY ACID (SCFA) AND BIO-TRANSFORMED BILE ACID (BA) HAVE BEEN SHOWN TO INFLUENCE THE IMMUNE SYSTEM ACTING AS LIGANDS SPECIFIC CELL SIGNALING RECEPTORS LIKE GPRCS, TGR5 AND FXR, OR VIA EPIGENETIC PROCESSES. SIMILARLY, INTESTINAL PERMEABILITY (LEAKY GUT) AND BACTERIAL TRANSLOCATION ARE IMPORTANT CONTRIBUTORS TO CHRONIC SYSTEMIC INFLAMMATION AND, WITHOUT REPAIR OF THE INTESTINAL BARRIER, MIGHT REPRESENT A CONTINUOUS INFLAMMATORY STIMULUS CAPABLE OF TRIGGERING AUTOIMMUNE PROCESSES. RECENT STUDIES INDICATE GENDER-SPECIFIC DIFFERENCES IN IMMUNITY, WITH THE GUT MICROBIOTA SHAPING AND BEING CONCOMITANTLY SHAPED BY THE HORMONAL MILIEU GOVERNING DIFFERENCES BETWEEN THE SEXES. A BI-DIRECTIONAL CROSS-TALK BETWEEN MICROBIOTA AND THE ENDOCRINE SYSTEM IS EMERGING WITH BACTERIA BEING ABLE TO PRODUCE HORMONES (E.G. SEROTONIN, DOPAMINE AND SOMATOSTATINE), RESPOND TO HOST HORMONES (E.G. ESTROGENS) AND REGULATE HOST HORMONES' HOMEOSTASIS (E.G BY INHIBITING GENE PROLACTIN TRANSCRIPTION OR CONVERTING GLUCOCORTICOIDS TO ANDROGENS). WE REVIEW HEREIN HOW GUT MICROBIOTA AND ITS METABOLITES REGULATE IMMUNE FUNCTION, INTESTINAL PERMEABILITY AND POSSIBLY AID PATHOLOGICAL PROCESSES. FURTHER, WE DESCRIBE THE DYSBIOSIS WITHIN THE GUT MICROBIOTA OBSERVED IN DIFFERENT AID AND SPECULATE HOW RESTORING GUT MICROBIOTA COMPOSITION AND ITS REGULATORY METABOLITES BY DIETARY INTERVENTION INCLUDING PREBIOTICS AND PROBIOTICS COULD HELP IN PREVENTING OR AMELIORATING AID. FINALLY, WE SUGGEST THAT, GIVEN CONSISTENT OBSERVATIONS OF MICROBIOTA DYSBIOSIS ASSOCIATED WITH AID AND THE ABILITY OF SCFA AND BA TO REGULATE INTESTINAL PERMEABILITY AND INFLAMMATION, FURTHER MECHANISTIC STUDIES, EXAMINING HOW DIETARY MICROBIOTA MODULATION CAN PROTECT AGAINST AID, HOLD CONSIDERABLE POTENTIAL TO TACKLE INCREASED INCIDENCE OF AID AT THE POPULATION LEVEL. 2018 20 2344 25 EPIGENETIC REGULATION OF MACROPHAGES: FROM HOMEOSTASIS MAINTENANCE TO HOST DEFENSE. MACROPHAGES ARE CRUCIAL MEMBERS OF THE INNATE IMMUNE RESPONSE AND IMPORTANT REGULATORS. THE DIFFERENTIATION AND ACTIVATION OF MACROPHAGES REQUIRE THE TIMELY REGULATION OF GENE EXPRESSION, WHICH DEPENDS ON THE INTERACTION OF A VARIETY OF FACTORS, INCLUDING TRANSCRIPTION FACTORS AND EPIGENETIC MODIFICATIONS. EPIGENETIC CHANGES ALSO GIVE MACROPHAGES THE ABILITY TO SWITCH RAPIDLY BETWEEN CELLULAR PROGRAMS, INDICATING THE ABILITY OF EPIGENETIC MECHANISMS TO AFFECT PHENOTYPE PLASTICITY. IN THIS REVIEW, WE FOCUS ON KEY EPIGENETIC EVENTS ASSOCIATED WITH MACROPHAGE FATE, HIGHLIGHTING EVENTS RELATED TO THE MAINTENANCE OF TISSUE HOMEOSTASIS, RESPONSES TO DIFFERENT STIMULI AND THE FORMATION OF INNATE IMMUNE MEMORY. FURTHER UNDERSTANDING OF THE EPIGENETIC REGULATION OF MACROPHAGES WILL BE HELPFUL FOR MAINTAINING TISSUE INTEGRITY, PREVENTING CHRONIC INFLAMMATORY DISEASES AND DEVELOPING THERAPIES TO ENHANCE HOST DEFENSE. 2020