1 1149 172 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 2 2617 55 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 3 3692 45 INFLAMMATORY BOWEL DISEASES: THE ROLE OF GUT MICROBIOTA. INFLAMMATORY BOWEL DISEASES (IBD) ARE CHRONIC MULTIFACTORIAL DISEASES CHARACTERIZED BY PARTIALLY UNCLEAR PATHOGENIC MECHANISMS INCLUDING CHANGES IN INTESTINAL MICROBIOTA. DESPITE THE MICROBIOTA, ALTERATION IS WELL ESTABLISHED IN IBD PATIENTS, AS REPORTED BY 16RNA SEQUENCING ANALYSIS, AN IMPORTANT GOAL IS TO DEFINE IF IT IS JUST A CONSEQUENCE OF THE DISEASE PROGRESSION OR A TRIGGER FACTOR OF THE DISEASE ITSELF. TO DATE, GUT MICROBIOTA COMPOSITION AND GUT MICROBIOTA-RELATED METABOLITES SEEM TO AFFECT THE HOST HEALTHY STATE BOTH BY MODULATING METABOLIC PATHWAYS OR ACTING ON THE EXPRESSION OF DIFFERENT GENES THROUGH EPIGENETIC EFFECTS. BECAUSE OF THIS, IT HAS BEEN SUGGESTED THAT INTESTINAL MICROBIOTA MIGHT REPRESENT A PROMISING THERAPEUTIC TARGET FOR IBD PATIENTS. THE AIM OF THIS REVIEW IS TO SUMMARIZE BOTH THE MOST RECENT ACQUISITIONS IN THE FIELD OF GUT MICROBIOTA AND ITS INVOLVEMENT IN INTESTINAL INFLAMMATION TOGETHER WITH THE AVAILABLE STRATEGIES FOR THE MODULATION OF MICROBIOTA, SUCH AS PREBIOTICS AND/OR PROBIOTICS ADMINISTRATION OR FECAL MICROBIOTA TRANSPLANTATION. 2020 4 1404 42 DIETARY COMPOSITION AND EFFECTS IN INFLAMMATORY BOWEL DISEASE. DRAMATIC CHANGES IN THE ENVIRONMENT AND HUMAN LIFESTYLE HAVE BEEN ASSOCIATED WITH THE RISE OF VARIOUS CHRONIC COMPLEX DISEASES, SUCH AS INFLAMMATORY BOWEL DISEASE (IBD). A DYSBIOTIC GUT MICROBIOTA HAS BEEN PROPOSED AS A CRUCIAL PATHOGENIC ELEMENT, CONTRIBUTING TO IMMUNE IMBALANCES AND FOSTERING A PROINFLAMMATORY MILIEU, WHICH MAY BE ASSOCIATED WITH DISEASE RELAPSES OR EVEN THE INITIATION OF IBD. IN ADDITION TO REPRESENTING IMPORTANT REGULATORS OF THE MUCOSAL IMMUNITY AND THE COMPOSITION OF THE GUT MICROBIOTA, FOOD COMPONENTS HAVE BEEN SHOWN TO BE POTENTIAL ENVIRONMENTAL TRIGGERS OF EPIGENETIC MODIFICATIONS. IN THE CONTEXT OF CHRONIC INTESTINAL INFLAMMATION, DIETARY HABITS AND SPECIFIC FOOD COMPONENTS HAVE BEEN IMPLICATED AS IMPORTANT MODULATORS OF EPIGENETIC MECHANISMS, INCLUDING DNA METHYLATION, WHICH MAY PREDISPOSE A PERSON TO THE INCREASED RISK OF THE INITIATION AND EVOLUTION OF IBD. THIS REVIEW PROVIDES NOVEL INSIGHTS ABOUT HOW DIETARY FACTORS MAY INTERACT WITH THE INTESTINAL MUCOSA AND MODULATE IMMUNE HOMEOSTASIS BY SHAPING THE INTESTINAL ECOSYSTEM, AS WELL AS THE POTENTIAL INFLUENCE OF DIET IN THE ETIOPATHOGENESIS AND MANAGEMENT OF IBD. 2019 5 1400 37 DIET-REGULATING MICROBIOTA AND HOST IMMUNE SYSTEM IN LIVER DISEASE. THE GUT MICROBIOTA HAS BEEN KNOWN TO MODULATE THE IMMUNE RESPONSES IN CHRONIC LIVER DISEASES. RECENT EVIDENCE SUGGESTS THAT EFFECTS OF DIETARY FOODS ON HEALTH CARE AND HUMAN DISEASES ARE RELATED TO BOTH THE IMMUNE REACTION AND THE MICROBIOME. THE GUT-MICROBIOME AND INTESTINAL IMMUNE SYSTEM PLAY A CENTRAL ROLE IN THE CONTROL OF BACTERIAL TRANSLOCATION-INDUCED LIVER DISEASE. DYSBIOSIS, SMALL INTESTINAL BACTERIAL OVERGROWTH, TRANSLOCATION, ENDOTOXEMIA, AND THE DIRECT EFFECTS OF METABOLITES ARE THE MAIN EVENTS IN THE GUT-LIVER AXIS, AND IMMUNE RESPONSES ACT ON EVERY PATHWAYS OF CHRONIC LIVER DISEASE. MICROBIOME-DERIVED METABOLITES OR BACTERIA THEMSELVES REGULATE IMMUNE CELL FUNCTIONS SUCH AS RECOGNITION OR ACTIVATION OF RECEPTORS, THE CONTROL OF GENE EXPRESSION BY EPIGENETIC CHANGE, ACTIVATION OF IMMUNE CELLS, AND THE INTEGRATION OF CELLULAR METABOLISM. HERE, WE REVIEWED RECENT REPORTS ABOUT THE IMMUNOLOGIC ROLE OF GUT MICROBIOTAS IN LIVER DISEASE, HIGHLIGHTING THE ROLE OF DIET IN CHRONIC LIVER DISEASE. 2021 6 5540 47 ROLE OF DIET AND GUT MICROBIOTA ON COLORECTAL CANCER IMMUNOMODULATION. COLORECTAL CANCER (CRC) IS ONE OF THE MOST COMMONLY DIAGNOSED CANCERS, AND IT IS CHARACTERIZED BY GENETIC AND EPIGENETIC ALTERATIONS, AS WELL AS BY INFLAMMATORY CELL INFILTRATION AMONG MALIGNANT AND STROMAL CELLS. HOWEVER, THIS DYNAMIC INFILTRATION CAN BE INFLUENCED BY THE MICROENVIRONMENT TO PROMOTE TUMOR PROLIFERATION, SURVIVAL AND METASTASIS OR CANCER INHIBITION. IN PARTICULAR, THE CANCER MICROENVIRONMENT METABOLITES CAN REGULATE THE INFLAMMATORY CELLS TO INDUCE A CHRONIC INFLAMMATORY RESPONSE THAT CAN BE A PREDISPOSING CONDITION FOR CRC RETENTION. IN ADDITION, SOME NUTRITIONAL COMPONENTS MIGHT CONTRIBUTE TO A CHRONIC INFLAMMATORY CONDITION BY REGULATING VARIOUS IMMUNE AND INFLAMMATORY PATHWAYS. BESIDES THAT, DIET STRONGLY MODULATES THE GUT MICROBIOTA COMPOSITION, WHICH HAS A KEY ROLE IN MAINTAINING GUT HOMEOSTASIS AND IS ASSOCIATED WITH THE MODULATION OF HOST INFLAMMATORY AND IMMUNE RESPONSES. THEREFORE, DIET HAS A FUNDAMENTAL ROLE IN CRC INITIATION, PROGRESSION AND PREVENTION. IN PARTICULAR, FUNCTIONAL FOODS SUCH AS PROBIOTICS, PREBIOTICS AND SYMBIOTICS CAN HAVE A POTENTIALLY POSITIVE EFFECT ON HEALTH BEYOND BASIC NUTRITION AND HAVE ANTI-INFLAMMATORY EFFECTS. IN THIS REVIEW, WE DISCUSS THE INFLUENCE OF DIET ON GUT MICROBIOTA COMPOSITION, FOCUSING ON ITS ROLE ON GUT INFLAMMATION AND IMMUNITY. FINALLY, WE DESCRIBE THE POTENTIAL BENEFITS OF USING PROBIOTICS AND PREBIOTICS TO MODULATE THE HOST INFLAMMATORY RESPONSE, AS WELL AS ITS APPLICATION IN CRC PREVENTION AND TREATMENT. 2019 7 6879 40 [RELATIONSHIP BETWEEN INTESTINAL HYPERPERMEABILITY AND OBESITY]. OBESITY IS A COMBINATION OF GENETIC, ENVIRONMENTAL FACTORS, AND SYSTEMIC INFLAMMATION OF ADIPOSE TISSUE. IN THE LAST DECADE, MORE AND MORE EVIDENCE SUGGESTS THAT INTESTINAL MICROBIOTA IS AN ENVIRONMENTAL FACTOR THAT PLAYS A CRUCIAL ROLE IN OBESITY AND ASSOCIATED METABOLIC DISORDERS. HERE, WE REVIEW THE ASSOCIATION BETWEEN INTESTINAL MICROBIOTA AND OBESITY BASED ON THE LITERATURE DATA AVAILABLE TO US. THE INTESTINAL FLORA, IN THE EQUILIBRIUM STATE OF CONVENTIONAL BACTERIA, PROTECTS THE HEALTH OF THE HOST AND HELPS THE DEVELOPMENT OF THE IMMUNE SYSTEM. THE GENOME, DIET, LIFESTYLE, AND EPIGENETIC CHANGES OF THE HOST CAN PATHOLOGICALLY ALTER THE COMPOSITION OF THE MICROBIOTA. IN DYSBIOSIS, THE DEVELOPMENT OF THE GUT-ASSOCIATED LYMPHOID TISSUE (GALT) ASSOCIATED WITH THE INTESTINAL TRACT IS IMPAIRED AND THE INTEGRITY OF THE INTESTINAL BARRIER IS IMPAIRED. DUE TO THE CONSEQUENT INTESTINAL HYPERPERMEABILITY, COMPONENTS OF PATHOGENIC PATHOGENS SUCH AS LIPOPOLYSACCHARIDES ENTER THE BLOODSTREAM. THESE COMPONENTS BIND TO RECEPTORS ON ADIPOSE TISSUE IMMUNE CELLS AS LIGANDS FOR MOLECULAR SAMPLES WITH PATHOGENIC PROPERTIES AND INDUCE ADIPOSE TISSUE DYSFUNCTION. THE SECRETION OF INFLAMMATORY CYTOKINES IN ADIPOSE TISSUE IS INCREASED. THIS INDUCES PERSISTENT LOW CHRONIC INFLAMMATION, WHICH IS RESPONSIBLE FOR THE DEVELOPMENT OF OBESITY. THE DAMAGE TO HEALTH CAUSED BY THE HYPERPERMEABILITY OF THE INTESTINAL BARRIER CAN BE REDUCED BY INTERVENTIONS, OR RESTORED EARLY IN THE PROCESS. KNOWING THE RELATIONSHIPS WILL HELP PREVENT AND TREAT OBESITY. 2022 8 5558 44 ROLE OF GUT MICROBIOTA IN THE AETIOLOGY OF OBESITY: PROPOSED MECHANISMS AND REVIEW OF THE LITERATURE. THE AETIOLOGY OF OBESITY HAS BEEN ATTRIBUTED TO SEVERAL FACTORS (ENVIRONMENTAL, DIETARY, LIFESTYLE, HOST, AND GENETIC FACTORS); HOWEVER NONE OF THESE FULLY EXPLAIN THE INCREASE IN THE PREVALENCE OF OBESITY WORLDWIDE. GUT MICROBIOTA LOCATED AT THE INTERFACE OF HOST AND ENVIRONMENT IN THE GUT ARE A NEW AREA OF RESEARCH BEING EXPLORED TO EXPLAIN THE EXCESS ACCUMULATION OF ENERGY IN OBESE INDIVIDUALS AND MAY BE A POTENTIAL TARGET FOR THERAPEUTIC MANIPULATION TO REDUCE HOST ENERGY STORAGE. SEVERAL MECHANISMS HAVE BEEN SUGGESTED TO EXPLAIN THE ROLE OF GUT MICROBIOTA IN THE AETIOLOGY OF OBESITY SUCH AS SHORT CHAIN FATTY ACID PRODUCTION, STIMULATION OF HORMONES, CHRONIC LOW-GRADE INFLAMMATION, LIPOPROTEIN AND BILE ACID METABOLISM, AND INCREASED ENDOCANNABINOID RECEPTOR SYSTEM TONE. HOWEVER, EVIDENCE FROM ANIMAL AND HUMAN STUDIES CLEARLY INDICATES CONTROVERSIES IN DETERMINING THE CAUSE OR EFFECT RELATIONSHIP BETWEEN THE GUT MICROBIOTA AND OBESITY. METAGENOMICS BASED STUDIES INDICATE THAT FUNCTIONALITY RATHER THAN THE COMPOSITION OF GUT MICROBIOTA MAY BE IMPORTANT. FURTHER MECHANISTIC STUDIES CONTROLLING FOR ENVIRONMENTAL AND EPIGENETIC FACTORS ARE THEREFORE REQUIRED TO HELP UNRAVEL OBESITY PATHOGENESIS. 2016 9 4273 41 MICROBIOTA AND EPIGENETICS: HEALTH IMPACT. EPIGENETIC CHANGES ASSOCIATED WITH DISEASE DEVELOPMENT AND PROGRESSIONS ARE OF INCREASING IMPORTANCE BECAUSE OF THEIR POTENTIAL DIAGNOSTIC AND THERAPEUTIC APPLICATIONS. SEVERAL EPIGENETIC CHANGES ASSOCIATED WITH CHRONIC METABOLIC DISORDERS HAVE BEEN STUDIED IN VARIOUS DISEASES. EPIGENETIC CHANGES ARE MOSTLY MODULATED BY ENVIRONMENTAL FACTORS, INCLUDING THE HUMAN MICROBIOTA LIVING IN DIFFERENT PARTS OF OUR BODIES. THE MICROBIAL STRUCTURAL COMPONENTS AND THE MICROBIALLY DERIVED METABOLITES DIRECTLY INTERACT WITH HOST CELLS, THEREBY MAINTAINING HOMEOSTASIS. MICROBIOME DYSBIOSIS, ON THE OTHER HAND, IS KNOWN TO PRODUCE ELEVATED LEVELS OF DISEASE-LINKED METABOLITES, WHICH MAY DIRECTLY AFFECT A HOST METABOLIC PATHWAY OR INDUCE EPIGENETIC CHANGES THAT CAN LEAD TO DISEASE DEVELOPMENT. DESPITE THEIR IMPORTANT ROLE IN HOST PHYSIOLOGY AND SIGNAL TRANSDUCTION, THERE HAS BEEN LITTLE RESEARCH INTO THE MECHANICS AND PATHWAYS ASSOCIATED WITH EPIGENETIC MODIFICATIONS. THIS CHAPTER FOCUSES ON THE RELATIONSHIP BETWEEN MICROBES AND THEIR EPIGENETIC EFFECTS IN DISEASED PATHOLOGY, AS WELL AS ON THE REGULATION AND METABOLISM OF THE DIETARY OPTIONS AVAILABLE TO THE MICROBES. FURTHERMORE, THIS CHAPTER ALSO PROVIDES A PROSPECTIVE LINK BETWEEN THESE TWO IMPORTANT PHENOMENA, TERMED "MICROBIOME AND EPIGENETICS." 2023 10 1395 46 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 11 3172 50 GUT MICROBIOTA AND RISK OF DEVELOPING CELIAC DISEASE. GUT MICROBIOTA SHAPES THE DEVELOPMENT OF THE MUCOSAL IMMUNE SYSTEM AND MAY PROVIDE PROTECTION AGAINST IMMUNE-MEDIATED DISEASES. CELIAC DISEASE (CD) IS A CHRONIC INFLAMMATORY CONDITION TRIGGERED BY DIETARY GLUTEN PROTEINS, RECENTLY ASSOCIATED WITH GUT MICROBIOTA ALTERATIONS IN CROSS-SECTIONAL STUDIES COMPARING PATIENTS AND CONTROLS. WHETHER OR NOT THESE DIFFERENCES ARE CAUSALLY RELATED TO THE DISEASE HAS YET TO BE ELUCIDATED, BUT EVALUATION OF SPECIFIC BACTERIA ISOLATED FROM CD PATIENTS IN EXPERIMENTAL MODELS SUGGESTS THAT THEY CAN PROMOTE AN ADVERSE RESPONSE TO DIETARY GLUTEN, WHEREAS OTHER COMMENSAL BACTERIA CAN BE PROTECTIVE. GENETIC AND ENVIRONMENTAL FACTORS ASSOCIATED WITH INCREASED CD RISK HAVE ALSO BEEN LINKED TO SHIFTS IN THE GUT MICROBIOTA COMPOSITION IN INFANTS EARLY IN LIFE. EPIGENETIC MECHANISMS ALSO SEEM TO PLAY AN IMPORTANT ROLE IN MODULATING GUT MICROBIOTA COMPOSITION AND FUNCTION AND, THEORETICALLY, COULD ALSO INFLUENCE CD RISK. HERE, WE REVIEW THE CURRENT KNOWLEDGE ON HOW HOST GENETICS, ENVIRONMENTAL FACTORS, AND EPIGENETIC MODIFICATIONS COULD MODULATE GUT MICROBIOTA FUNCTIONALITY AND HOW THIS MAY INFLUENCE CD RISK. GREATER UNDERSTANDING OF THE ROLE OF THIS TRIAD IN CD ONSET AND PATHOGENESIS WILL BE VALUABLE IN DESIGNING PROOF-OF CONCEPT INTERVENTIONS IN THE GUT ECOSYSTEM, WITH A VIEW TO IMPROVING CD MANAGEMENT. 2016 12 3601 46 IMPORTANCE OF PROBIOTICS IN THE PREVENTION AND TREATMENT OF COLORECTAL CANCER. COLORECTAL CANCER (CRC) REMAINS ONE OF THE MOST COMMON AND DEADLY CANCERS. INTESTINAL GUT MICROFLORA IS IMPORTANT TO MAINTAIN AND CONTRIBUTES TO SEVERAL INTESTINAL FUNCTIONS, INCLUDING THE DEVELOPMENT OF THE MUCOSAL IMMUNE SYSTEM, ABSORPTION OF COMPLEX MACROMOLECULES, SYNTHESIS OF AMINO ACIDS/VITAMINS AND THE PROTECTION AGAINST PATHOGENIC MICROORGANISMS. IT IS WELL KNOWN THAT THE GUT MICROBIOTA CHANGES OR DYSBIOSIS MAY HAVE AN ESSENTIAL IMPACT IN THE INITIATION AND PROMOTION OF CHRONIC INFLAMMATORY PATHWAYS AND ALSO HAVE A PROFOUND DIFFERENT GENETIC AND EPIGENETIC ALTERATIONS LEADING TO DYSPLASIA, CLONAL EXPANSION, AND MALIGNANT TRANSFORMATION. PROBIOTIC BACTERIA HAS ANTITUMOR ACTIVITY WITH VARIOUS MECHANISMS SUCH AS NONSPECIFIC PHYSIOLOGICAL AND IMMUNOLOGICAL MECHANISMS. THIS REVIEW EVALUATES THE EFFECTS OF MICROBIOTA AND PROBIOTICS IN CLINICAL TRIALS, IN VITRO AND ANIMAL MODEL STUDIES THAT HAVE EXPLORED HOW PROBIOTIC AGAINST CANCER DEVELOPMENT AND ALSO DISCUSSES THE POSSIBLE IMMUNOMODULATORY MECHANISMS. SEVERAL MECHANISMS ALTERATION OF THE INTESTINAL MICROFLORA; INACTIVATION OF CANCEROGENIC COMPOUNDS; COMPETITION WITH PUTREFACTIVE AND PATHOGENIC MICROBIOTA; IMPROVEMENT OF THE HOST'S IMMUNE RESPONSE; ANTIPROLIFERATIVE EFFECTS VIA REGULATION OF APOPTOSIS AND CELL DIFFERENTIATION; FERMENTATION OF UNDIGESTED FOOD; INHIBITION OF TYROSINE KINASE; REDUCES THE ENTEROPATHOGENIC COMPLICATIONS BEFORE AND AFTER COLON CANCER SURGERY AND IMPROVE DIARRHEA AND IT'S HAVE BEEN ABLE TO CREATE THE INTEGRITY OF GUT MUCOSAL AND HAVE STIMULATORY EFFECTS ON THE SYSTEMIC IMMUNE SYSTEM AND PREVENT THE CRC METASTASIS. RESEARCH IN CLINICAL TRIALS ENCOURAGING FINDINGS THAT SUPPORT A ROLE OF PROBIOTICS IN CRC PREVENTION AND IMPROVE THE SAFETY AND EFFECTIVENESS OF CANCER THERAPY EVEN THOUGH ADDITIONAL CLINICAL RESEARCH IS STILL NECESSARY. 2019 13 3546 41 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 14 3585 45 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 15 566 38 BASES FOR THE ADEQUATE DEVELOPMENT OF NUTRITIONAL RECOMMENDATIONS FOR PATIENTS WITH INFLAMMATORY BOWEL DISEASE. INFLAMMATORY BOWEL DISEASE (IBD) IS A CHRONIC AND RELAPSING INFLAMMATORY CONDITION OF THE GASTROINTESTINAL TRACT; IT IS A HETEROGENEOUS AND MULTIFACTORIAL DISORDER RESULTING FROM A COMPLEX INTERPLAY BETWEEN GENETIC VARIATION, INTESTINAL MICROBIOTA, THE HOST IMMUNE SYSTEM AND ENVIRONMENTAL FACTORS SUCH AS DIET, DRUGS, BREASTFEEDING AND SMOKING. THE INTERACTIONS BETWEEN DIETARY NUTRIENTS AND INTESTINAL IMMUNITY ARE COMPLEX. THERE IS A COMPELLING ARGUMENT FOR ENVIRONMENTAL FACTORS SUCH AS DIET PLAYING A ROLE IN THE CAUSE AND COURSE OF IBD, GIVEN THAT THREE IMPORTANT FACTORS IN THE PATHOGENESIS OF IBD CAN BE MODULATED AND CONTROLLED BY DIET: INTESTINAL MICROBIOTA, THE IMMUNE SYSTEM AND EPITHELIAL BARRIER FUNCTION. THE AIM OF THIS REVIEW IS TO SUMMARIZE THE EPIDEMIOLOGICAL FINDINGS REGARDING DIET AND TO FOCUS ON THE EFFECTS THAT NUTRIENTS EXERT ON THE INTESTINAL MUCOSA-MICROBIOTA-PERMEABILITY INTERACTION. THE NATURE OF THESE INTERACTIONS IN IBD IS INFLUENCED BY ALTERATIONS IN THE NUTRITIONAL METABOLISM OF THE GUT MICROBIOTA AND HOST CELLS THAT CAN INFLUENCE THE OUTCOME OF NUTRITIONAL INTERVENTION. A BETTER UNDERSTANDING OF DIET-HOST-MICROBIOTA INTERACTIONS IS ESSENTIAL FOR UNRAVELLING THE COMPLEX MOLECULAR BASIS OF EPIGENETIC, GENETIC AND ENVIRONMENTAL INTERACTIONS UNDERLYING IBD PATHOGENESIS AS WELL AS FOR OFFERING NEW THERAPEUTIC APPROACHES FOR THE TREATMENT OF IBD. 2019 16 6034 41 THE CHALLENGE BY MULTIPLE ENVIRONMENTAL AND BIOLOGICAL FACTORS INDUCE INFLAMMATION IN AGING: THEIR ROLE IN THE PROMOTION OF CHRONIC DISEASE. THE AGING PROCESS IS DRIVEN BY MULTIPLE MECHANISMS THAT LEAD TO CHANGES IN ENERGY PRODUCTION, OXIDATIVE STRESS, HOMEOSTATIC DYSREGULATION AND EVENTUALLY TO LOSS OF FUNCTIONALITY AND INCREASED DISEASE SUSCEPTIBILITY. MOST AGED INDIVIDUALS DEVELOP CHRONIC LOW-GRADE INFLAMMATION, WHICH IS AN IMPORTANT RISK FACTOR FOR MORBIDITY, PHYSICAL AND COGNITIVE IMPAIRMENT, FRAILTY, AND DEATH. AT ANY AGE, CHRONIC INFLAMMATORY DISEASES ARE MAJOR CAUSES OF MORBIMORTALITY, AFFECTING UP TO 5-8% OF THE POPULATION OF INDUSTRIALIZED COUNTRIES. SEVERAL ENVIRONMENTAL FACTORS CAN PLAY AN IMPORTANT ROLE FOR MODIFYING THE INFLAMMATORY STATE. GENETICS ACCOUNTS FOR ONLY A SMALL FRACTION OF CHRONIC-INFLAMMATORY DISEASES, WHEREAS ENVIRONMENTAL FACTORS APPEAR TO PARTICIPATE, EITHER WITH A CAUSATIVE OR A PROMOTIONAL ROLE IN 50% TO 75% OF PATIENTS. SEVERAL OF THOSE CHANGES DEPEND ON EPIGENETIC CHANGES THAT WILL FURTHER MODIFY THE INDIVIDUAL RESPONSE TO ADDITIONAL STIMULI. THE INTERACTION BETWEEN INFLAMMATION AND THE ENVIRONMENT OFFERS IMPORTANT INSIGHTS ON AGING AND HEALTH. THESE CONDITIONS, OFTEN DEPENDING ON THE INDIVIDUAL'S SEX, APPEAR TO LEAD TO DECREASED LONGEVITY AND PHYSICAL AND COGNITIVE DECLINE. IN ADDITION TO BIOLOGICAL FACTORS, THE ENVIRONMENT IS ALSO INVOLVED IN THE GENERATION OF PSYCHOLOGICAL AND SOCIAL CONTEXT LEADING TO STRESS. POOR PSYCHOLOGICAL ENVIRONMENTS AND OTHER SOURCES OF STRESS ALSO RESULT IN INCREASED INFLAMMATION. HOWEVER, THE MECHANISMS UNDERLYING THE ROLE OF ENVIRONMENTAL AND PSYCHOSOCIAL FACTORS AND NUTRITION ON THE REGULATION OF INFLAMMATION, AND HOW THE RESPONSE ELICITED FOR THOSE FACTORS INTERACT AMONG THEM, ARE POORLY UNDERSTOOD. WHEREAS CERTAIN DELETERIOUS ENVIRONMENTAL FACTORS RESULT IN THE GENERATION OF OXIDATIVE STRESS DRIVEN BY AN INCREASED PRODUCTION OF REACTIVE OXYGEN AND NITROGEN SPECIES, ENDOPLASMIC RETICULUM STRESS, AND INFLAMMATION, OTHER FACTORS, INCLUDING NUTRITION (POLYUNSATURATED FATTY ACIDS) AND BEHAVIORAL FACTORS (EXERCISE) CONFER PROTECTION AGAINST INFLAMMATION, OXIDATIVE AND ENDOPLASMIC RETICULUM STRESS, AND THUS AMELIORATE THEIR DELETERIOUS EFFECT. HERE, WE DISCUSS PROCESSES AND MECHANISMS OF INFLAMMATION ASSOCIATED WITH ENVIRONMENTAL FACTORS AND BEHAVIOR, THEIR LINKS TO SEX AND GENDER, AND THEIR OVERALL IMPACT ON AGING. 2020 17 6251 45 THE MICROBIOLOGICAL MEMORY, AN EPIGENETIC REGULATOR GOVERNING THE BALANCE BETWEEN GOOD HEALTH AND METABOLIC DISORDERS. IF THE TRANSMISSION OF BIOLOGICAL INFORMATION FROM ONE GENERATION TO THE NEXT IS BASED ON DNA, MOST HERITABLE PHENOTYPIC TRAITS SUCH AS CHRONIC METABOLIC DISEASES, ARE NOT LINKED TO GENETIC VARIATION IN DNA SEQUENCES. NON-GENETIC HERITABILITY MIGHT HAVE SEVERAL CAUSES INCLUDING EPIGENETIC, PARENTAL EFFECT, ADAPTIVE SOCIAL LEARNING, AND INFLUENCE OF THE ECOLOGICAL ENVIRONMENT. DISTINGUISHING AMONG THESE CAUSES IS CRUCIAL TO RESOLVE MAJOR PHENOTYPIC ENIGMAS. STRONG EVIDENCE INDICATES THAT CHANGES IN DNA EXPRESSION THROUGH VARIOUS EPIGENETIC MECHANISMS CAN BE LINKED TO PARENT-OFFSPRING RESEMBLANCE IN TERMS OF SENSITIVITY TO METABOLIC DISEASES. AMONG NON-GENETIC HERITABLE TRAITS, EARLY NUTRITION COULD ACCOUNT FOR A LONG TERM DEVIANT PROGRAMMING OF GENES EXPRESSION RESPONSIBLE FOR METABOLIC DISEASES IN ADULTHOOD. NUTRITION COULD SHAPE AN INADEQUATE GUT MICROBIOTA (DYSBIOSIS), TRIGGERING EPIGENETIC DEREGULATION OF TRANSCRIPTION WHICH CAN BE OBSERVED IN CHRONIC METABOLIC DISEASES. WE REVIEW HEREIN THE EVIDENCE THAT DYSBIOSIS MIGHT BE A MAJOR CAUSE OF HERITABLE EPIGENETIC PATTERNS FOUND TO BE ASSOCIATED WITH METABOLIC DISEASES. BY TAKING INTO ACCOUNT THE RECENT ADVANCES ON THE GUT MICROBIOME, WE HAVE AGGREGATED TOGETHER DIFFERENT OBSERVATIONS SUPPORTING THE HYPOTHESIS THAT THE GUT MICROBIOTA COULD PROMOTE THE MOLECULAR CROSSTALK BETWEEN BACTERIA AND SURROUNDING HOST CELLS WHICH CONTROLS THE PATHOLOGICAL EPIGENETIC SIGNATURE. WE INTRODUCE FOR THE FIRST TIME THE CONCEPT OF "MICROBIOLOGICAL MEMORY" AS THE MAIN REGULATOR OF THE EPIGENETIC SIGNATURES, THEREBY INDICATING THAT DIFFERENT CAUSES OF NON-GENETIC HERITABILITY CAN INTERACT IN COMPLEX PATHWAYS TO PRODUCE INHERITANCE. 2018 18 838 46 CHEMISTRY MEETS BIOLOGY IN COLITIS-ASSOCIATED CARCINOGENESIS. THE INTESTINE COMPRISES AN EXCEPTIONAL VENUE FOR A DYNAMIC AND COMPLEX INTERPLAY OF NUMEROUS CHEMICAL AND BIOLOGICAL PROCESSES. HERE, MULTIPLE CHEMICAL AND BIOLOGICAL SYSTEMS, INCLUDING THE INTESTINAL TISSUE ITSELF, ITS ASSOCIATED IMMUNE SYSTEM, THE GUT MICROBIOTA, XENOBIOTICS, AND METABOLITES MEET AND INTERACT TO FORM A SOPHISTICATED AND TIGHTLY REGULATED STATE OF TISSUE HOMOEOSTASIS. DISTURBANCE OF THIS HOMEOSTASIS CAN CAUSE INFLAMMATORY BOWEL DISEASE (IBD)-A CHRONIC DISEASE OF MULTIFACTORIAL ETIOLOGY THAT IS STRONGLY ASSOCIATED WITH INCREASED RISK FOR CANCER DEVELOPMENT. THIS REVIEW ADDRESSES RECENT DEVELOPMENTS IN RESEARCH INTO CHEMICAL AND BIOLOGICAL MECHANISMS UNDERLYING THE ETIOLOGY OF INFLAMMATION-INDUCED COLON CANCER. BEGINNING WITH A GENERAL OVERVIEW OF REACTIVE CHEMICAL SPECIES GENERATED DURING COLONIC INFLAMMATION, THE MECHANISTIC INTERPLAY BETWEEN CHEMICAL AND BIOLOGICAL MEDIATORS OF INFLAMMATION, THE ROLE OF GENETIC TOXICOLOGY, AND MICROBIAL PATHOGENESIS IN DISEASE DEVELOPMENT ARE DISCUSSED. WHEN POSSIBLE, WE SYSTEMATICALLY COMPARE EVIDENCE FROM STUDIES UTILIZING HUMAN IBD PATIENTS WITH EXPERIMENTAL INVESTIGATIONS IN MICE. THE COMPARISON REVEALS THAT MANY STRONG PATHOLOGICAL AND MECHANISTIC CORRELATES EXIST BETWEEN MOUSE MODELS OF COLITIS-ASSOCIATED CANCER, AND THE CLINICALLY RELEVANT SITUATION IN HUMANS. WE ALSO SUMMARIZE SEVERAL EMERGING ISSUES IN THE FIELD, SUCH AS THE CARCINOGENIC POTENTIAL OF NOVEL INFLAMMATION-RELATED DNA ADDUCTS AND GENOTOXIC MICROBIAL FACTORS, THE SYSTEMIC DIMENSION OF INFLAMMATION-INDUCED GENOTOXICITY, AND THE COMPLEX ROLE OF GENOME MAINTENANCE MECHANISMS DURING THESE PROCESSES. TAKEN TOGETHER, CURRENT EVIDENCE POINTS TO THE INDUCTION OF GENETIC AND EPIGENETIC ALTERATIONS BY CHEMICAL AND BIOLOGICAL INFLAMMATORY STIMULI ULTIMATELY LEADING TO CANCER FORMATION. 2013 19 6252 36 THE MICROBIOME AND CANCER: IMPLICATIONS FOR ONCOLOGY NURSING SCIENCE. BACKGROUND: APPROXIMATELY 1.6 MILLION AMERICANS WERE DIAGNOSED WITH CANCER IN 2014. TO COMBAT THEIR DISEASE, MANY INDIVIDUALS RECEIVED EITHER CURATIVE OR PALLIATIVE TREATMENTS THAT PRODUCED UNDESIRED SYMPTOMS. THESE SYMPTOMS, WHICH OFTEN CAUSE SIGNIFICANT DISTRESS FOR INDIVIDUALS COPING WITH CANCER, MAY SHARE BIOLOGIC UNDERPINNINGS SUCH AS EPIGENETIC CHANGES AND IMMUNE DYSREGULATION. ALTERATIONS IN THE NORMAL FLORA OF THE GUT MAY ALSO INFLUENCE CANCER SYMPTOMS. OBJECTIVE: THE AIM OF THIS REVIEW IS TO DESCRIBE THE EMERGING ROLE FOR THE GUT MICROBIOME IN CANCER RESEARCH, ESPECIALLY THE POTENTIAL RELATIONSHIP BETWEEN THE GUT MICROBIOME AND CANCER SYMPTOMS. METHODS: EXTANT LITERATURE WAS REVIEWED AND SYNTHESIZED. RESULTS: THE MAJORITY OF STUDIES LINKING THE GUT MICROBIOTA AND CANCER ARE ANIMAL MODELS AND FOCUS ON THE RELATIONSHIP BETWEEN DYSBIOSIS AND COLORECTAL CANCER. EMERGING EVIDENCE SUPPORTS THAT THE "GUT-BRAIN" CONNECTION IS A PLAUSIBLE MECHANISM FOR "PSYCHONEUROLOGICAL" CANCER SYMPTOMS SUCH AS DEPRESSION, PAIN, AND FATIGUE. CONCLUSIONS: THERE IS COMPELLING EVIDENCE THAT THE GUT MICROBIOTA AFFECTS CANCER VIA SEVERAL MECHANISMS, INCLUDING MICROBIAL DIVERSITY AND NUMBER, METABOLISM, AND/OR IMMUNE INITIATION. HOWEVER, MORE RESEARCH IS NECESSARY TO ELUCIDATE THESE MECHANISMS, PARTICULARLY AMONG A VARIETY OF CANCERS AND CANCER-RELATED SYMPTOMS. IMPLICATIONS FOR PRACTICE: A BETTER UNDERSTANDING OF THE ROLE OF THE GUT MICROBIOTA IN CANCER SYMPTOMS MAY LEAD TO THE DEVELOPMENT OF TARGETED INDIVIDUALIZED INTERVENTIONS AFFECTING THE GUT MICROBIOTA THAT PREVENT OR AMELIORATE DYSBIOSIS, THEREBY REDUCING SYMPTOMS. THESE INTERVENTIONS MAY EMPHASIZE SELF-CARE MANAGEMENT STRATEGIES ESSENTIAL FOR WELLNESS, SUCH AS DIET, NUTRITION, AND STRESS REDUCTION. 2016 20 1168 50 CONTRIBUTION OF EPITHELIAL AND GUT MICROBIOME INFLAMMATORY BIOMARKERS TO THE IMPROVEMENT OF COLORECTAL CANCER PATIENTS' STRATIFICATION. IN ORDER TO ENSURE THAT PRIMARY ENDPOINTS OF CLINICAL STUDIES ARE ATTAINED, THE PATIENTS' STRATIFICATION IS AN IMPORTANT ASPECT. SELECTION CRITERIA INCLUDE AGE, GENDER, AND ALSO SPECIFIC BIOMARKERS, SUCH AS INFLAMMATION SCORES. THESE CRITERIA ARE NOT SUFFICIENT TO ACHIEVE A STRAIGHTFORWARD SELECTION, HOWEVER, IN CASE OF MULTIFACTORIAL DISEASES, WITH UNKNOWN OR PARTIALLY IDENTIFIED MECHANISMS, OCCASIONALLY INCLUDING HOST FACTORS, AND THE MICROBIOME. IN THESE CASES, THE EFFICACY OF INTERVENTIONS IS DIFFICULT TO PREDICT, AND AS A RESULT, THE SELECTION OF SUBJECTS IS OFTEN RANDOM. COLORECTAL CANCER (CRC) IS A HIGHLY HETEROGENEOUS DISEASE, WITH VARIABLE CLINICAL FEATURES, OUTCOMES, AND RESPONSE TO THERAPY; THE CRC ONSET AND PROGRESS INVOLVES MULTIPLE SEQUENTIAL STEPS WITH ACCUMULATION OF GENETIC ALTERATIONS, NAMELY, MUTATIONS, GENE AMPLIFICATION, AND EPIGENETIC CHANGES. THE GUT MICROBES, EITHER EUBIOTIC OR DYSBIOTIC, COULD INFLUENCE THE CRC EVOLUTION THROUGH A COMPLEX AND VERSATILE CROSSTALK WITH THE INTESTINAL AND IMMUNE CELLS, PERMANENTLY CHANGING THE TUMOR MICROENVIRONMENT. THERE HAVE BEEN SIGNIFICANT ADVANCES IN THE DEVELOPMENT OF PERSONALIZED APPROACHES FOR CRC SCREENING, TREATMENT, AND POTENTIAL PREVENTION. ADVANCES IN MOLECULAR TECHNIQUES BRING NEW CRITERIA FOR PATIENTS' STRATIFICATION-MUTATIONAL ANALYSIS AT THE TIME OF DIAGNOSIS TO GUIDE TREATMENT, FOR EXAMPLE. GUT MICROBIOME HAS EMERGED AS THE MAIN TRIGGER OF GUT MUCOSAL HOMEOSTASIS. THIS MAY IMPACT CANCER SUSCEPTIBILITY THROUGH MAINTENANCE OF THE EPITHELIAL/MUCUS BARRIER AND PRODUCTION OF PROTECTIVE METABOLITES, SUCH AS SHORT-CHAIN FATTY ACIDS (SCFAS) VIA INTERACTIONS WITH THE HOSTS' DIET AND METABOLISM. MICROBIOME DYSBIOSIS LEADS TO THE ENRICHMENT OF CANCER-PROMOTING BACTERIAL POPULATIONS, LOSS OF PROTECTIVE POPULATIONS OR MAINTAINING AN INFLAMMATORY CHRONIC STATE, ALL OF WHICH CONTRIBUTE TO THE DEVELOPMENT AND PROGRESSION OF CRC. MEANWHILE, VARIATIONS IN PATIENT RESPONSES TO ANTI-CANCER IMMUNO- AND CHEMOTHERAPIES WERE ALSO LINKED TO INTER-INDIVIDUAL DIFFERENCES IN INTESTINE MICROBIOMES. THE AUTHORS AIM TO HIGHLIGHT THE CONTRIBUTION OF EPITHELIAL AND GUT MICROBIOME INFLAMMATORY BIOMARKERS IN THE IMPROVEMENT OF CRC PATIENTS' STRATIFICATION TOWARDS A PERSONALIZED APPROACH OF EARLY DIAGNOSIS AND TREATMENT. 2021