1 3678 153 INFLAMMATION AND REGENERATION IN THE DENTIN-PULP COMPLEX: A DOUBLE-EDGED SWORD. DENTAL TISSUE INFECTION AND DISEASE RESULT IN ACUTE AND CHRONIC ACTIVATION OF THE INNATE IMMUNE RESPONSE, WHICH IS MEDIATED BY MOLECULAR AND CELLULAR SIGNALING. DIFFERENT CELL TYPES WITHIN THE DENTIN-PULP COMPLEX ARE ABLE TO DETECT INVADING BACTERIA AT ALL STAGES OF THE INFECTION. INDEED, AT RELATIVELY EARLY DISEASE STAGES, ODONTOBLASTS WILL RESPOND TO BACTERIAL COMPONENTS, AND AS THE DISEASE PROGRESSES, CORE PULPAL CELLS INCLUDING FIBROBLASTS, STEMS CELLS, ENDOTHELIAL CELLS, AND IMMUNE CELLS WILL BECOME INVOLVED. PATTERN RECOGNITION RECEPTORS, SUCH AS TOLL-LIKE RECEPTORS EXPRESSED ON THESE CELL TYPES, ARE RESPONSIBLE FOR DETECTING BACTERIAL COMPONENTS, AND THEIR LIGAND BINDING LEADS TO THE ACTIVATION OF THE NUCLEAR FACTOR-KAPPA B AND P38 MITOGEN-ACTIVATED PROTEIN (MAP) KINASE INTRACELLULAR SIGNALING CASCADES. SUBSEQUENT NUCLEAR TRANSLOCATION OF THE TRANSCRIPTION FACTOR SUBUNITS FROM THESE PATHWAYS WILL LEAD TO PROINFLAMMATORY MEDIATOR EXPRESSION, INCLUDING INCREASES IN CYTOKINES AND CHEMOKINES, WHICH TRIGGER HOST CELLULAR DEFENSE MECHANISMS. THE COMPLEX MOLECULAR SIGNALING WILL RESULT IN THE RECRUITMENT OF IMMUNE SYSTEM CELLS TARGETED AT COMBATING THE INVADING MICROBES; HOWEVER, THE TRAFFICKING AND ANTIBACTERIAL ACTIVITY OF THESE CELLS CAN LEAD TO COLLATERAL TISSUE DAMAGE. RECENT EVIDENCE SUGGESTS THAT IF INFLAMMATION IS RESOLVED RELATIVELY LOW LEVELS OF PROINFLAMMATORY MEDIATORS MAY PROMOTE TISSUE REPAIR, WHEREAS IF CHRONIC INFLAMMATION ENSUES REPAIR MECHANISMS BECOME INHIBITED. THUS, THE EFFECTS OF MEDIATORS ARE TEMPORAL CONTEXT DEPENDENT. ALTHOUGH CONTAINMENT AND REMOVAL OF THE INFECTION ARE KEYS TO ENABLE DENTAL TISSUE REPAIR, IT IS FEASIBLE THAT THE DEVELOPMENT OF ANTI-INFLAMMATORY AND IMMUNOMODULATORY APPROACHES, BASED ON MOLECULAR, EPIGENETIC, AND PHOTOBIOMODULATORY TECHNOLOGIES, MAY ALSO BE BENEFICIAL FOR FUTURE ENDODONTIC TREATMENTS. 2014 2 5437 39 REMOTE HIND-LIMB ISCHEMIA MECHANISM OF PRESERVED EJECTION FRACTION DURING HEART FAILURE. DURING ACUTE HEART FAILURE (HF), REMOTE ISCHEMIC CONDITIONING (RIC) HAS PROVEN TO BE BENEFICIAL; HOWEVER, IT IS CURRENTLY UNCLEAR WHETHER IT ALSO EXTENDS BENEFITS FROM CHRONIC CONGESTIVE, CARDIOPULMONARY HEART FAILURE (CHF). PREVIOUS STUDIES FROM OUR LABORATORY HAVE SHOWN THREE PHASES DESCRIBING CHF VIZ. (1) HF WITH PRESERVED EJECTION FRACTION (HFPEF), (2) HF WITH REDUCED EF (HFREF), AND (3) HF WITH REVERSED EF. ALTHOUGH RECIPROCAL ORGAN INTERACTION, ABLATION OF SYMPATHETIC, AND CALCIUM SIGNALING GENES ARE ASSOCIATED WITH HFPEF TO HFREF, THE MECHANISM IS UNCLEAR. THE HFREF ENSUES, IN PART, DUE TO REDUCED ANGIOGENESIS, CORONARY RESERVE, AND LEAKAGE OF ENDOCARDIAL ENDOTHELIAL (EE) AND FINALLY BREAKDOWN OF THE BLOOD-HEART BARRIER (BHB) INTEGRITY. IN FACT, OUR HYPOTHESIS STATES THAT A CHANGE IN PHENOTYPE FROM COMPENSATORY HFPEF TO DECOMPENSATORY HFREF IS DETERMINED BY A POTENTIAL DECREASE IN REGENERATIVE, PROANGIOGENIC FACTORS ALONG WITH A CONCOMITANT INCREASE IN EPIGENETIC MEMORY, INFLAMMATION THAT COMBINEDLY CAUSES OXIDATIVE, AND PROTEOLYTIC STRESS RESPONSE. TO TEST THIS HYPOTHESIS, WE CREATED CHF BY AORTA-VENA-CAVA (AV) FISTULA IN A GROUP OF MICE THAT WERE SUBSEQUENTLY TREATED WITH THAT OF HIND-LIMB RIC. HFPEF VS. HFREF TRANSITION WAS DETERMINED BY SERIAL/LONGITUDINAL ECHO MEASUREMENTS. RESULTS REVEALED AN INCREASE IN SKELETAL MUSCLE MUSCLIN CONTENTS, BONE-MARROW (CD71), AND SYMPATHETIC ACTIVATION (BETA2-AR) BY RIC. WE ALSO OBSERVED A DECREASE IN VASCULAR DENSITY AND ATTENUATION OF EE-BHB FUNCTION DUE TO A CORRESPONDING INCREASE IN THE ACTIVITY OF MMP-2, VASCULAR ENDOTHELIAL GROWTH FACTOR (VEGF), CASPASE, AND CALPAIN. THIS DECREASE WAS SUCCESSFULLY MITIGATED BY RIC-RELEASED SKELETAL MUSCLE EXOSOMES THAT CONTAIN MUSCLIN, THE MYOKINE ALONG WITH BONE MARROW, AND SYMPATHETIC ACTIVATION. IN SHORT, BASED ON PROTEOME (OMICS) ANALYSIS, APPROXIMATELY 20 PROTEINS THAT APPEAR TO BE INVOLVED IN SIGNALING PATHWAYS RESPONSIBLE FOR THE SYNTHESIS, CONTRACTION, AND RELAXATION OF CARDIAC MUSCLE WERE FOUND TO BE THE DOMINANT FEATURES. THUS, OUR RESULTS SUPPORT THAT THE CHF PHENOTYPE CAUSES DYSFUNCTION OF CARDIAC METABOLISM, ITS CONTRACTION, AND RELAXATION. INTERESTINGLY, RIC WAS ABLE TO MITIGATE MANY OF THE DELETERIOUS CHANGES, AS REVEALED BY OUR MULTI-OMICS FINDINGS. 2021 3 4271 36 MICROBIAL DYSBIOSIS-INDUCED OBESITY: ROLE OF GUT MICROBIOTA IN HOMOEOSTASIS OF ENERGY METABOLISM. THE GLOBAL OBESITY EPIDEMIC HAS NECESSITATED THE SEARCH FOR BETTER INTERVENTION STRATEGIES INCLUDING THE EXPLOITATION OF THE HEALTH BENEFITS OF SOME GUT MICROBIOTA AND THEIR METABOLIC PRODUCTS. THEREFORE, WE EXAMINED THE GUT MICROBIAL COMPOSITION AND MECHANISMS OF INTERACTION WITH THE HOST IN RELATION TO HOMOEOSTATIC ENERGY METABOLISM AND PATHOPHYSIOLOGY OF DYSBIOSIS-INDUCED METABOLIC INFLAMMATION AND OBESITY. WE ALSO DISCUSSED THE EUBIOTIC, HEALTH-PROMOTING EFFECTS OF PROBIOTICS AND PREBIOTICS AS WELL AS EPIGENETIC MODIFICATIONS ASSOCIATED WITH GUT MICROBIAL DYSBIOSIS AND RISK OF OBESITY. HIGH-FAT/CARBOHYDRATE DIET PROGRAMMES THE GUT MICROBIOTA TO ONE PREDOMINATED BY FIRMICUTES (CLOSTRIDIUM), PREVOTELLA AND METHANOBREVIBACTER BUT DEFICIENT IN BENEFICIAL GENERA/SPECIES SUCH AS BACTEROIDES, BIFIDOBACTERIUM, LACTOBACILLUS AND AKKERMANSIA. ALTERED GUT MICROBIOTA IS ASSOCIATED WITH DECREASED EXPRESSION OF SCFA THAT MAINTAIN INTESTINAL EPITHELIAL BARRIER INTEGRITY, REDUCE BACTERIAL TRANSLOCATION AND INFLAMMATION AND INCREASE EXPRESSION OF HUNGER-SUPPRESSING HORMONES. REDUCED AMOUNTS OF BENEFICIAL MICRO-ORGANISMS ALSO INHIBIT FASTING-INDUCED ADIPOCYTE FACTOR EXPRESSION LEADING TO DYSLIPIDAEMIA. A LOW-GRADE CHRONIC INFLAMMATION (METABOLIC ENDOTOXAEMIA) ENSUES WHICH CULMINATES IN OBESITY AND ITS CO-MORBIDITIES. THE SYNERGY OF HIGH-FAT DIET AND DYSBIOTIC GUT MICROBIOTA INITIATES A RECIPE THAT EPIGENETICALLY PROGRAMMES THE HOST FOR INCREASED ADIPOSITY AND POOR GLYCAEMIC CONTROL. INTERESTINGLY, THESE OBESOGENIC MECHANISTIC PATHWAYS THAT ARE TRANSMITTABLE FROM ONE GENERATION TO ANOTHER CAN BE MODULATED THROUGH THE ADMINISTRATION OF PROBIOTICS, PREBIOTICS AND SYNBIOTICS. THOUGH THE INFLUENCE OF GUT MICROBIOTA ON THE RISK OF OBESITY AND SEVERAL INTERVENTION STRATEGIES HAVE BEEN EXTENSIVELY DEMONSTRATED IN ANIMAL MODELS, APPLICATION IN HUMANS STILL REQUIRES FURTHER ROBUST INVESTIGATION. 2020 4 5429 26 REGULATION OF TYPE I INTERFERON RESPONSES. TYPE I INTERFERONS (IFNS) ACTIVATE INTRACELLULAR ANTIMICROBIAL PROGRAMMES AND INFLUENCE THE DEVELOPMENT OF INNATE AND ADAPTIVE IMMUNE RESPONSES. CANONICAL TYPE I IFN SIGNALLING ACTIVATES THE JANUS KINASE (JAK)-SIGNAL TRANSDUCER AND ACTIVATOR OF TRANSCRIPTION (STAT) PATHWAY, LEADING TO TRANSCRIPTION OF IFN-STIMULATED GENES (ISGS). HOST, PATHOGEN AND ENVIRONMENTAL FACTORS REGULATE THE RESPONSES OF CELLS TO THIS SIGNALLING PATHWAY AND THUS CALIBRATE HOST DEFENCES WHILE LIMITING TISSUE DAMAGE AND PREVENTING AUTOIMMUNITY. HERE, WE SUMMARIZE THE SIGNALLING AND EPIGENETIC MECHANISMS THAT REGULATE TYPE I IFN-INDUCED STAT ACTIVATION AND ISG TRANSCRIPTION AND TRANSLATION. THESE REGULATORY MECHANISMS DETERMINE THE BIOLOGICAL OUTCOMES OF TYPE I IFN RESPONSES AND WHETHER PATHOGENS ARE CLEARED EFFECTIVELY OR CHRONIC INFECTION OR AUTOIMMUNE DISEASE ENSUES. 2014 5 4769 37 NUCLEAR MORPHOMETRY, NUCLEOMICS AND PROSTATE CANCER PROGRESSION. PROSTATE CANCER (PCA) RESULTS FROM A MULTISTEP PROCESS. THIS PROCESS INCLUDES INITIATION, WHICH OCCURS THROUGH VARIOUS AGING EVENTS AND MULTIPLE INSULTS (SUCH AS CHRONIC INFECTION, INFLAMMATION AND GENETIC INSTABILITY THROUGH REACTIVE OXYGEN SPECIES CAUSING DNA DOUBLE-STRAND BREAKS), FOLLOWED BY A MULTISTEP PROCESS OF PROGRESSION. THESE STEPS INCLUDE SEVERAL GENETIC AND EPIGENETIC ALTERATIONS, AS WELL AS ALTERATIONS TO THE CHROMATIN STRUCTURE, WHICH OCCUR IN RESPONSE TO THE CARCINOGENIC STRESS-RELATED EVENTS THAT SUSTAIN PROLIFERATIVE SIGNALING. EVENTS SUCH AS EVADING GROWTH SUPPRESSORS, RESISTING CELL DEATH, ENABLING REPLICATIVE IMMORTALITY, INDUCING ANGIOGENESIS, AND ACTIVATING INVASION AND METASTASIS ARE READILY OBSERVED. IN ADDITION, IN CONJUNCTION WITH THESE CRITICAL DRIVERS OF CARCINOGENESIS, OTHER FACTORS RELATED TO THE ETIOPATHOGENESIS OF PCA, INVOLVING ENERGY METABOLISM AND EVASION OF THE IMMUNE SURVEILLANCE SYSTEM, APPEAR TO BE INVOLVED. IN ADDITION, WHEN CANCER SPREAD AND METASTASIS OCCUR, THE 'TUMOR MICROENVIRONMENT' IN THE BONE OF PCA PATIENTS MAY PROVIDE A WAY TO SUSTAIN DORMANCY OR SENESCENCE AND EVENTUALLY ESTABLISH A 'SEED AND SOIL' SITE WHERE PCA PROLIFERATION AND GROWTH MAY OCCUR OVER TIME. WHEN PCA IS INITIATED AND PROGRESSION ENSUES, SIGNIFICANT ALTERATIONS IN NUCLEAR SIZE, SHAPE AND HETEROCHROMATIN (DNA TRANSCRIPTION) ORGANIZATION ARE FOUND, AND KEY NUCLEAR TRANSCRIPTIONAL AND STRUCTURAL PROTEINS, AS WELL AS MULTIPLE NUCLEAR BODIES CAN LEAD TO PRECANCEROUS AND MALIGNANT CHANGES. THESE SERIES OF CELLULAR AND TISSUE-RELATED MALIGNANCY-ASSOCIATED EVENTS CAN BE QUANTIFIED TO ASSESS DISEASE PROGRESSION AND MANAGEMENT. 2012 6 4070 31 MATERNAL DIABETES, PROGRAMMING OF BETA-CELL DISORDERS AND INTERGENERATIONAL RISK OF TYPE 2 DIABETES. A SUBSTANTIAL BODY OF EVIDENCE SUGGESTS THAT AN ABNORMAL INTRA-UTERINE MILIEU ELICITED BY MATERNAL METABOLIC DISTURBANCES AS DIVERSE AS MALNUTRITION, PLACENTAL INSUFFICIENCY, DIABETES AND OBESITY MAY BE ABLE TO PROGRAMME SUSCEPTIBILITY OF THE FOETUS TO LATER DEVELOP CHRONIC DEGENERATIVE DISEASES SUCH AS OBESITY, HYPERTENSION, CARDIOVASCULAR DISEASES AND TYPE 2 DIABETES (T2D). AS INSULIN-PRODUCING CELLS HAVE BEEN PLACED CENTRE STAGE IN THE DEVELOPMENT OF T2D, THIS REVIEW EXAMINES DEVELOPMENTAL PROGRAMMING OF THE BETA-CELL MASS (BCM) IN VARIOUS RODENT MODELS OF MATERNAL PROTEIN RESTRICTION, CALORIE RESTRICTION, OVERNUTRITION AND DIABETES. THE MAIN MESSAGE IS THAT WHATEVER THE INITIAL MATERNAL INSULT (F0 GENERATION) AND WHETHER ALONE OR IN COMBINATION, IT GIVES RISE TO THE SAME PROGRAMMED BCM OUTCOME IN THE DAUGHTER GENERATION (F1). THE ALTERED BCM PHENOTYPE IN F1 FEMALES PROHIBITS NORMAL BCM ADAPTATION DURING PREGNANCY AND, THUS, DIABETES (GESTATIONAL DIABETES) ENSUES. THIS GESTATIONAL DIABETES IS THEN PASSED FROM ONE GENERATION (F1) TO THE NEXT (F2, F3 AND SO ON). THIS REVIEW HIGHLIGHTS A NUMBER OF STUDIES THAT HAVE IDENTIFIED EPIGENETIC MECHANISMS THAT MAY CONTRIBUTE TO ALTERED BCM DEVELOPMENT AND BETA-CELL FAILURE, AS OBSERVED IN DIABETES. IN ADDITION TO THEIR ROLE IN INSTILLING THE PROGRAMMED DEFECT, THESE NON-GENOMIC MECHANISMS MAY ALSO BE INVOLVED IN ITS INTERGENERATIONAL TRANSMISSION. 2014 7 3379 25 HIV LATENCY AND THE NONCODING RNA THERAPEUTIC LANDSCAPE. THE HUMAN IMMUNODEFICIENCY VIRUS (HIV) BELONGS TO THE SUBFAMILY OF LENTIVIRUSES THAT ARE CHARACTERIZED BY LONG INCUBATION PERIODS AND CHRONIC, PERSISTENT INFECTION. THE VIRUS INTEGRATES INTO THE GENOME OF INFECTED CD4+ CELLS AND, IN A SUBPOPULATION OF CELLS, ADOPTS A TRANSCRIPTIONALLY SILENT STATE, A PROCESS REFERRED TO A VIRAL LATENCY. THIS PROPERTY MAKES IT EXCEEDINGLY DIFFICULT TO THERAPEUTICALLY TARGET THE VIRUS AND ERADICATE INFECTION. IF LEFT UNTREATED, THE INEXORABLE DEMISE OF THE INFECTED INDIVIDUAL'S IMMUNE SYSTEM ENSUES, A CAUSAL RESULT OF ACQUIRED IMMUNODEFICIENCY SYNDROME (AIDS). LATENTLY INFECTED CELLS PROVIDE A RESERVOIR THAT MAINTAINS VIRAL INFECTION INDEFINITELY. IN THIS CHAPTER WE EXPLORE THE ROLE OF NONCODING RNAS IN HIV INFECTION AND IN THE ESTABLISHMENT AND MAINTENANCE OF VIRAL LATENCY. BOTH SHORT AND LONG NONCODING RNAS ARE ENDOGENOUS MODULATORS OF EPIGENETIC REGULATION IN HUMAN CELLS AND PLAY AN ACTIVE ROLE IN GENE EXPRESSION. LASTLY, WE EXPLORE THERAPEUTIC MODALITIES BASED ON EXPRESSED RNAS THAT ARE CAPABLE OF COUNTERING INFECTION, TRANSCRIPTIONALLY REGULATING THE VIRUS, AND SUPPRESSING OR ACTIVATING THE LATENT STATE. 2015 8 6502 32 TRAINED IMMUNITY: LONG-TERM ADAPTATION IN INNATE IMMUNE RESPONSES. ADAPTIVE IMMUNE RESPONSES ARE CHARACTERIZED BY ANTIGEN SPECIFICITY AND INDUCTION OF LIFELONG IMMUNOLOGIC MEMORY. RECENTLY, IT HAS BEEN REPORTED THAT INNATE IMMUNE CELLS CAN ALSO BUILD IMMUNE MEMORY CHARACTERISTICS-A PROCESS TERMED TRAINED IMMUNITY. TRAINED IMMUNITY DESCRIBES THE PERSISTENT HYPERRESPONSIVE PHENOTYPE THAT INNATE IMMUNE CELLS CAN DEVELOP AFTER BRIEF STIMULATION. PATHOGENIC STIMULI SUCH AS MICROORGANISMS, AND ALSO ENDOGENOUS MOLECULES INCLUDING URIC ACID, OXIDIZED LDL (LOW-DENSITY LIPOPROTEIN), AND CATECHOLAMINES, ARE CAPABLE OF INDUCING MEMORY IN MONOCYTES AND MACROPHAGES. WHILE TRAINED IMMUNITY PROVIDES FAVORABLE CROSS-PROTECTION IN THE CONTEXT OF INFECTIOUS DISEASES, THE HEIGHTENED IMMUNE RESPONSE CAN BE MALADAPTIVE IN DISEASES DRIVEN BY CHRONIC SYSTEMIC INFLAMMATION, SUCH AS ATHEROSCLEROSIS. TRAINED IMMUNITY IS MAINTAINED BY DISTINCT EPIGENETIC AND METABOLIC MECHANISMS AND PERSISTS FOR AT LEAST SEVERAL MONTHS IN VIVO DUE TO REPROGRAMMING OF MYELOID PROGENITOR CELLS. ADDITIONALLY, CERTAIN NONIMMUNE CELLS ARE ALSO FOUND TO EXHIBIT TRAINED IMMUNITY CHARACTERISTICS. THUS, TRAINED IMMUNITY PRESENTS AN EXCITING FRAMEWORK TO DEVELOP NEW APPROACHES TO VACCINATION AND ALSO NOVEL PHARMACOLOGICAL TARGETS IN THE TREATMENT OF INFLAMMATORY DISEASES. 2021 9 2537 24 EPIGENETICS IN HEART FAILURE PHENOTYPES. CHRONIC HEART FAILURE (HF) IS A LEADING CLINICAL AND PUBLIC PROBLEM POSING A HIGHER RISK OF MORBIDITY AND MORTALITY IN DIFFERENT POPULATIONS. HF APPEARS TO BE IN BOTH PHENOTYPIC FORMS: HF WITH REDUCED LEFT VENTRICULAR EJECTION FRACTION (HFREF) AND HF WITH PRESERVED LEFT VENTRICULAR EJECTION FRACTION (HFPEF). ALTHOUGH BOTH HF PHENOTYPES CAN BE DISTINGUISHED THROUGH CLINICAL FEATURES, CO-MORBIDITY STATUS, PREDICTION SCORE, AND TREATMENT, THE CLINICAL OUTCOMES IN PATIENTS WITH HFREF AND HFPEF ARE SIMILAR. IN THIS CONTEXT, INVESTIGATION OF VARIOUS MOLECULAR AND CELLULAR MECHANISMS LEADING TO THE DEVELOPMENT AND PROGRESSION OF BOTH HF PHENOTYPES IS VERY IMPORTANT. THERE IS EMERGING EVIDENCE THAT EPIGENETIC REGULATION MAY HAVE A CLUE IN THE PATHOGENESIS OF HF. THIS REVIEW REPRESENTS CURRENT AVAILABLE EVIDENCE REGARDING THE IMPLICATION OF EPIGENETIC MODIFICATIONS IN THE DEVELOPMENT OF DIFFERENT HF PHENOTYPES AND PERSPECTIVES OF EPIGENETIC-BASED THERAPIES OF HF. 2016 10 1310 25 DEFINING TRAINED IMMUNITY AND ITS ROLE IN HEALTH AND DISEASE. IMMUNE MEMORY IS A DEFINING FEATURE OF THE ACQUIRED IMMUNE SYSTEM, BUT ACTIVATION OF THE INNATE IMMUNE SYSTEM CAN ALSO RESULT IN ENHANCED RESPONSIVENESS TO SUBSEQUENT TRIGGERS. THIS PROCESS HAS BEEN TERMED 'TRAINED IMMUNITY', A DE FACTO INNATE IMMUNE MEMORY. RESEARCH IN THE PAST DECADE HAS POINTED TO THE BROAD BENEFITS OF TRAINED IMMUNITY FOR HOST DEFENCE BUT HAS ALSO SUGGESTED POTENTIALLY DETRIMENTAL OUTCOMES IN IMMUNE-MEDIATED AND CHRONIC INFLAMMATORY DISEASES. HERE WE DEFINE 'TRAINED IMMUNITY' AS A BIOLOGICAL PROCESS AND DISCUSS THE INNATE STIMULI AND THE EPIGENETIC AND METABOLIC REPROGRAMMING EVENTS THAT SHAPE THE INDUCTION OF TRAINED IMMUNITY. 2020 11 5326 42 PULP INNATE IMMUNE DEFENSE: TRANSLATIONAL OPPORTUNITIES. INTRODUCTION: THE IMPROVEMENT OF REGENERATIVE ENDODONTIC PROCEDURES REQUIRES AN UNDERSTANDING OF THE KEY CLINICAL QUESTIONS COMBINED WITH A FUNDAMENTAL BIOLOGICAL KNOWLEDGE OF HOW THE DENTAL TISSUES BEHAVE DURING HEALTH, DISEASE, AND REPAIR. THEREFORE, PARTNERSHIPS BETWEEN CLINICIANS AND BASIC SCIENTISTS ARE ESSENTIAL TO DRIVE THE FIELD FORWARD AND IMPROVE PATIENT OUTCOMES. METHODS: THIS REVIEW AIMED TO PROVIDE A BACKGROUND TO DENTIN-PULP BIOLOGY AND THE INTERACTION BETWEEN INFECTION, INFLAMMATION, AND REGENERATION. RESULTS: WE HAVE HIGHLIGHTED HOW THE RELEASE OF NEUTROPHIL EXTRACELLULAR TRAPS (NETS) WITHIN THE PULP ARE DOUBLE-EDGED; WHILE THEY AIM TO LIMIT THE BACTERIAL INFECTION, THEY MAY ACTUALLY EXACERBATE CELL DEATH AND CHRONIC INFLAMMATION. ABERRANT LEVELS OF THESE STRUCTURES MAY OCCUR BECAUSE OF INEFFECTIVE HOST IMMUNOLOGIC PROCESSES, VIRAL INFECTIONS, OR IMPAIRED CLEARANCE CAUSED BY BACTERIAL VIRULENCE FACTORS. WE ALSO POSTULATE A PROINFLAMMATORY LINK IN THE PULP BETWEEN NETS AND THE INFLAMMASOME ACTIVATED BY PATHOGEN-ASSOCIATED MOLECULAR PATTERNS AND DAMAGE-ASSOCIATED MOLECULAR PATTERNS. SUBSEQUENTLY, WE DISCUSS AREAS POTENTIALLY FRUITFUL FOR FUTURE CLINICAL EXPLOITATION INVOLVING NET INHIBITORS, INFLAMMASOME MODULATORS, PHOTOTHERAPIES, AND NOVEL EPIGENETIC APPROACHES. CONCLUSIONS: SUSTAINED SCIENTIST-CLINICIAN RESEARCH PARTNERSHIPS ALONG WITH AN INCREASED UNDERSTANDING OF THE ASSOCIATION BETWEEN INFLAMMATION AND REGENERATION WITHIN THE DENTIN-PULP COMPLEX WILL LEAD TO FUTURE PATIENT BENEFIT. 2020 12 6504 39 TRAINED INNATE IMMUNITY AND ITS IMPLICATIONS FOR MUCOSAL IMMUNITY AND INFLAMMATION. THE LONG-STANDING DOGMA THAT IMMUNOLOGICAL MEMORY IS THE EXCLUSIVE PREROGATIVE OF THE ADAPTIVE IMMUNE SYSTEM HAS BEEN CHALLENGED BY EMERGING EVIDENCE THAT INNATE IMMUNITY CAN ALSO MAINTAIN MEMORY OF PAST EVENTS. SUCH IMMUNOLOGICAL IMPRINTING TAKES TWO FORMS, TRAINED INNATE IMMUNITY AND TOLERANCE. TRAINED IMMUNITY INVOLVES METABOLIC AND EPIGENETIC ADAPTATIONS IN INNATE IMMUNE CELLS AND THEIR PROGENITORS IN THE BONE MARROW UPON EXPOSURE TO CERTAIN MICROBIAL AND/OR INFLAMMATORY STIMULI SO THAT THE "TRAINED" CELLS WOULD BE POISED TO RESPOND MUCH FASTER AND STRONGER TO A SUBSEQUENT CHALLENGE (E.G., A NEW INFECTION THAT IS NOT NECESSARILY THE SAME AS THE EARLIER ONE). CONVERSELY, TOLERANCE LEADS TO ATTENUATED IMMUNE RESPONSES TO SECONDARY STIMULI. THIS REVIEW FOCUSES ON TRAINED IMMUNITY AND DISCUSSES EVIDENCE FOR ITS EXISTENCE FROM LOWER ORGANISMS TO HUMANS, ITS MECHANISTIC UNDERPINNINGS, AND ITS TRANSLATIONAL RAMIFICATIONS. ALTHOUGH TRAINED IMMUNITY CAN BE CONSIDERED AS AN EVOLUTIONARILY CONSERVED BENEFICIAL RESPONSE AGAINST REINFECTIONS, IN THE SETTING OF MODERN SOCIETIES WITH HIGH PREVALENCE OF CHRONIC MUCOSAL AND SYSTEMIC INFLAMMATORY DISEASES, TRAINED IMMUNITY COULD ALSO PROMOTE MALADAPTIVE IMMUNE RESPONSES THAT AGGRAVATE PATHOLOGY. THUS, DEPENDING ON CONTEXT, INNATE IMMUNE MEMORY COULD BE THERAPEUTICALLY MANIPULATED USING DEFINED AGONISTS TO EITHER PROMOTE INNATE IMMUNE RESPONSES (PARTICULARLY USEFUL FOR THE TREATMENT OF INFECTIONS OR CHEMOTHERAPY-INDUCED MYELOSUPPRESSION) OR SUPPRESS EXCESSIVE INFLAMMATION IN INFLAMMATORY AND AUTOIMMUNE DISEASES. 2019 13 6503 32 TRAINED IMMUNITY: REPROGRAMMING INNATE IMMUNITY IN HEALTH AND DISEASE. TRADITIONALLY, THE INNATE AND ADAPTIVE IMMUNE SYSTEMS ARE DIFFERENTIATED BY THEIR SPECIFICITY AND MEMORY CAPACITY. IN RECENT YEARS, HOWEVER, THIS PARADIGM HAS SHIFTED: CELLS OF THE INNATE IMMUNE SYSTEM APPEAR TO BE ABLE TO GAIN MEMORY CHARACTERISTICS AFTER TRANSIENT STIMULATION, RESULTING IN AN ENHANCED RESPONSE UPON SECONDARY CHALLENGE. THIS PHENOMENON HAS BEEN CALLED TRAINED IMMUNITY. TRAINED IMMUNITY IS CHARACTERIZED BY NONSPECIFIC INCREASED RESPONSIVENESS, MEDIATED VIA EXTENSIVE METABOLIC AND EPIGENETIC REPROGRAMMING. TRAINED IMMUNITY EXPLAINS THE HETEROLOGOUS EFFECTS OF VACCINES, WHICH RESULT IN INCREASED PROTECTION AGAINST SECONDARY INFECTIONS. HOWEVER, IN CHRONIC INFLAMMATORY CONDITIONS, TRAINED IMMUNITY CAN INDUCE MALADAPTIVE EFFECTS AND CONTRIBUTE TO HYPERINFLAMMATION AND PROGRESSION OF CARDIOVASCULAR DISEASE, AUTOINFLAMMATORY SYNDROMES, AND NEUROINFLAMMATION. IN THIS REVIEW WE SUMMARIZE THE CURRENT STATE OF THE FIELD OF TRAINED IMMUNITY, ITS MECHANISMS, AND ITS ROLES IN BOTH HEALTH AND DISEASE. 2021 14 3544 33 IMMUNOMETABOLIC CONTROL OF TRAINED IMMUNITY. INNATE IMMUNE CELLS CAN ADOPT LONG-TERM INFLAMMATORY PHENOTYPES FOLLOWING BRIEF ENCOUNTERS WITH EXOGENOUS (MICROBIAL) OR ENDOGENOUS STIMULI. THIS PHENOMENON IS NAMED TRAINED IMMUNITY AND CAN IMPROVE HOST DEFENSE AGAINST (RECURRENT) INFECTIONS. IN CONTRAST, TRAINED IMMUNITY CAN ALSO BE MALADAPTIVE IN THE CONTEXT OF CHRONIC INFLAMMATORY DISORDERS, SUCH AS ATHEROSCLEROSIS. KEY TO FUTURE THERAPEUTIC EXPLOITATION OF THIS MECHANISM IS THOROUGH KNOWLEDGE OF THE MECHANISMS DRIVING TRAINED IMMUNITY, WHICH CAN BE USED AS PHARMACOLOGICAL TARGETS. THESE MECHANISMS INCLUDE PROFOUND CHANGES IN INTRACELLULAR METABOLISM, WHICH ARE CLOSELY INTERTWINED WITH EPIGENETIC REPROGRAMMING AT THE LEVEL OF HISTONE MODIFICATIONS. GLYCOLYSIS, GLUTAMINE REPLENISHMENT OF THE TRICARBOXYLIC ACID CYCLE WITH ACCUMULATION OF FUMARATE, AND THE MEVALONATE PATHWAY HAVE ALL BEEN IDENTIFIED AS CRITICAL PATHWAYS FOR TRAINED IMMUNITY IN MONOCYTES AND MACROPHAGES. IN THIS REVIEW, WE PROVIDE A STATE-OF-THE-ART OVERVIEW OF HOW THESE METABOLIC PATHWAYS INTERACT WITH EPIGENETIC PROGRAMS TO DEVELOP TRAINED IMMUNITY. 2021 15 6571 30 TRANSPOSABLE ELEMENTS CROSS KINGDOM BOUNDARIES AND CONTRIBUTE TO INFLAMMATION AND AGEING: SOMATIC ACQUISITION OF FOREIGN TRANSPOSABLE ELEMENTS AS A CATALYST OF GENOME INSTABILITY, EPIGENETIC DYSREGULATION, INFLAMMATION, SENESCENCE, AND AGEING. THE DE-REPRESSION OF TRANSPOSABLE ELEMENTS (TES) IN MAMMALIAN GENOMES IS THOUGHT TO CONTRIBUTE TO GENOME INSTABILITY, INFLAMMATION, AND AGEING, YET IS VIEWED AS A CELL-AUTONOMOUS EVENT. IN CONTRAST TO MAMMALIAN CELLS, PROKARYOTES CONSTANTLY EXCHANGE GENETIC MATERIAL THROUGH TES, CROSSING BOTH CELL AND SPECIES BARRIERS, CONTRIBUTING TO RAPID MICROBIAL EVOLUTION AND DIVERSITY IN COMPLEX COMMUNITIES SUCH AS THE MAMMALIAN GUT. HERE, IT IS PROPOSED THAT TES RELEASED FROM PROKARYOTES IN THE MICROBIOME OR FROM PATHOGENIC INFECTIONS REGULARLY CROSS THE KINGDOM BARRIER TO THE SOMATIC CELLS OF THEIR EUKARYOTIC HOSTS. IT IS PROPOSED THIS HORIZONTAL TRANSFER OF TES FROM MICROBE TO HOST IS A STOCHASTIC, ONGOING CATALYST OF GENOME DESTABILIZATION, RESULTING IN STRUCTURAL AND EPIGENETIC VARIATIONS, AND ACTIVATION OF WELL-EVOLVED HOST DEFENSE MECHANISMS CONTRIBUTING TO INFLAMMATION, SENESCENCE, AND BIOLOGICAL AGEING. IT IS PROPOSED THAT INNATE IMMUNITY PATHWAYS DEFEND AGAINST THE HORIZONTAL ACQUISITION OF MICROBIAL TES, AND THAT ACTIVATION OF THIS PATHWAY DURING HORIZONTAL TRANSPOSON TRANSFER PROMOTES CHRONIC INFLAMMATION DURING AGEING. FINALLY, IT IS SUGGESTED THAT HORIZONTAL ACQUISITION OF PROKARYOTIC TES INTO MAMMALIAN GENOMES HAS BEEN MASKED AND SUBSEQUENTLY UNDER-REPORTED DUE TO FLAWS IN CURRENT SEQUENCING PIPELINES, AND NEW STRATEGIES TO UNCOVER THESE EVENTS ARE PROPOSED. 2020 16 6376 32 THE ROLE OF NEUTROPHILS IN TRAINED IMMUNITY. THE PRINCIPLE OF TRAINED IMMUNITY REPRESENTS INNATE IMMUNE MEMORY DUE TO SUSTAINED, MAINLY EPIGENETIC, CHANGES TRIGGERED BY ENDOGENOUS OR EXOGENOUS STIMULI IN BONE MARROW (BM) PROGENITORS (CENTRAL TRAINED IMMUNITY) AND THEIR INNATE IMMUNE CELL PROGENY, THEREBY TRIGGERING ELEVATED RESPONSIVENESS AGAINST SECONDARY STIMULI. BM PROGENITORS CAN RESPOND TO MICROBIAL AND STERILE SIGNALS, THEREBY POSSIBLY ACQUIRING TRAINED IMMUNITY-MEDIATED LONG-LASTING ALTERATIONS THAT MAY SHAPE THE FATE AND FUNCTION OF THEIR PROGENY, FOR EXAMPLE, NEUTROPHILS. NEUTROPHILS, THE MOST ABUNDANT INNATE IMMUNE CELL POPULATION, ARE PRODUCED IN THE BM FROM COMMITTED PROGENITOR CELLS IN A PROCESS DESIGNATED GRANULOPOIESIS. NEUTROPHILS ARE THE FIRST RESPONDERS AGAINST INFECTIOUS OR INFLAMMATORY CHALLENGES AND HAVE VERSATILE FUNCTIONS IN IMMUNITY. TOGETHER WITH OTHER INNATE IMMUNE CELLS, NEUTROPHILS ARE EFFECTORS OF PERIPHERAL TRAINED IMMUNITY. HOWEVER, GIVEN THE SHORT LIFETIME OF NEUTROPHILS, THEIR ABILITY TO ACQUIRE IMMUNOLOGICAL MEMORY MAY LIE IN THE CENTRAL TRAINING OF THEIR BM PROGENITORS RESULTING IN GENERATION OF REPROGRAMMED, THAT IS, "TRAINED", NEUTROPHILS. ALTHOUGH TRAINED IMMUNITY MAY HAVE BENEFICIAL EFFECTS IN INFECTION OR CANCER, IT MAY ALSO MEDIATE DETRIMENTAL OUTCOMES IN CHRONIC INFLAMMATION. HERE, WE REVIEW THE EMERGING RESEARCH AREA OF TRAINED IMMUNITY WITH A PARTICULAR EMPHASIS ON THE ROLE OF NEUTROPHILS AND GRANULOPOIESIS. 2023 17 6494 30 TRAINED IMMUNITY AS A NOVEL THERAPEUTIC STRATEGY. RECENT STUDIES HAVE SHOWN THAT UPON CERTAIN VACCINATIONS OR INFECTIONS HUMAN INNATE IMMUNE CELLS CAN UNDERGO EXTENSIVE METABOLIC AND EPIGENETIC REPROGRAMMING, WHICH RESULTS IN ENHANCED IMMUNE RESPONSES UPON HETEROLOGOUS RE-INFECTION, A PROCESS TERMED TRAINED IMMUNITY. TRAINED IMMUNITY HAS ALSO BEEN SHOWN TO BE INAPPROPRIATELY ACTIVATED IN INFLAMMATORY DISEASES. THIS PROVIDES THE POTENTIAL FOR IDENTIFYING NOVEL THERAPEUTIC TARGETS: POTENTIATION OF TRAINED IMMUNITY COULD PROTECT FROM SECONDARY INFECTIONS AND REVERSE IMMUNOTOLERANT STATES, WHILE INHIBITION OF TRAINED IMMUNITY MIGHT REDUCE EXCESSIVE IMMUNE ACTIVATION IN CHRONIC INFLAMMATORY CONDITIONS. BY TARGETING SPECIFIC MECHANISMS OF TRAINED IMMUNITY ON EITHER IMMUNOLOGIC, METABOLIC OR EPIGENETIC LEVEL, NOVEL THERAPEUTIC APPROACHES COULD BE DEVELOPED. 2018 18 6497 31 TRAINED IMMUNITY IN ATHEROSCLEROTIC CARDIOVASCULAR DISEASE. TRAINED IMMUNITY, ALSO KNOWN AS INNATE IMMUNE MEMORY, IS A PERSISTENT HYPER-RESPONSIVE FUNCTIONAL STATE OF INNATE IMMUNE CELLS. ACCUMULATING EVIDENCE IMPLICATES TRAINED IMMUNITY AS AN UNDERLYING MECHANISM OF CHRONIC INFLAMMATION IN ATHEROSCLEROTIC CARDIOVASCULAR DISEASE. IN THIS CONTEXT, TRAINED IMMUNITY IS INDUCED BY ENDOGENOUS ATHEROSCLEROSIS-PROMOTING FACTORS, SUCH AS MODIFIED LIPOPROTEINS OR HYPERGLYCAEMIA, CAUSING BROAD METABOLIC AND EPIGENETIC REPROGRAMMING OF THE MYELOID CELL COMPARTMENT. IN ADDITION TO TRADITIONAL CARDIOVASCULAR RISK FACTORS, LIFESTYLE FACTORS, INCLUDING UNHEALTHY DIETS, SEDENTARY LIFESTYLE, SLEEP DEPRIVATION AND PSYCHOSOCIAL STRESS, AS WELL AS INFLAMMATORY COMORBIDITIES, HAVE BEEN SHOWN TO ACTIVATE TRAINED IMMUNITY-LIKE MECHANISMS IN BONE MARROW HAEMATOPOIETIC STEM CELLS. IN THIS REVIEW, WE DISCUSS THE MOLECULAR AND CELLULAR MECHANISMS OF TRAINED IMMUNITY, ITS SYSTEMIC REGULATION THROUGH HAEMATOPOIETIC PROGENITOR CELLS IN THE BONE MARROW, AND THE ACTIVATION OF THESE MECHANISMS BY CARDIOVASCULAR DISEASE RISK FACTORS. WE ALSO HIGHLIGHT OTHER TRAINED IMMUNITY FEATURES THAT ARE RELEVANT FOR ATHEROSCLEROTIC CARDIOVASCULAR DISEASE, INCLUDING THE DIVERSE CELL TYPES THAT SHOW MEMORY CHARACTERISTICS AND TRANSGENERATIONAL INHERITANCE OF TRAINED IMMUNITY TRAITS. FINALLY, WE PROPOSE POTENTIAL STRATEGIES FOR THE THERAPEUTIC MODULATION OF TRAINED IMMUNITY TO MANAGE ATHEROSCLEROTIC CARDIOVASCULAR DISEASE. 2023 19 6495 31 TRAINED IMMUNITY AS A POTENTIAL TARGET FOR THERAPEUTIC IMMUNOMODULATION IN DUCHENNE MUSCULAR DYSTROPHY. DYSREGULATED INFLAMMATION INVOLVING INNATE IMMUNE CELLS, PARTICULARLY OF THE MONOCYTE/MACROPHAGE LINEAGE, IS A KEY CONTRIBUTOR TO THE PATHOGENESIS OF DUCHENNE MUSCULAR DYSTROPHY (DMD). TRAINED IMMUNITY IS AN EVOLUTIONARILY ANCIENT PROTECTIVE MECHANISM AGAINST INFECTION, IN WHICH EPIGENETIC AND METABOLIC ALTERATIONS CONFER NON-SPECIFIC HYPERRESPONSIVENESS OF INNATE IMMUNE CELLS TO VARIOUS STIMULI. RECENT WORK IN AN ANIMAL MODEL OF DMD (MDX MICE) HAS SHOWN THAT MACROPHAGES EXHIBIT CARDINAL FEATURES OF TRAINED IMMUNITY, INCLUDING THE PRESENCE OF INNATE IMMUNE SYSTEM "MEMORY". THE LATTER IS REFLECTED BY EPIGENETIC CHANGES AND DURABLE TRANSMISSIBILITY OF THE TRAINED PHENOTYPE TO HEALTHY NON-DYSTROPHIC MICE BY BONE MARROW TRANSPLANTATION. MECHANISTICALLY, IT IS SUGGESTED THAT A TOLL-LIKE RECEPTOR (TLR) 4-REGULATED, MEMORY-LIKE CAPACITY OF INNATE IMMUNITY IS INDUCED AT THE LEVEL OF THE BONE MARROW BY FACTORS RELEASED FROM THE DAMAGED MUSCLES, LEADING TO EXAGGERATED UPREGULATION OF BOTH PRO- AND ANTI-INFLAMMATORY GENES. HERE WE PROPOSE A CONCEPTUAL FRAMEWORK FOR THE INVOLVEMENT OF TRAINED IMMUNITY IN DMD PATHOGENESIS AND ITS POTENTIAL TO SERVE AS A NEW THERAPEUTIC TARGET. 2023 20 3734 38 INNATE IMMUNE MEMORY IN MONOCYTES AND MACROPHAGES: THE POTENTIAL THERAPEUTIC STRATEGIES FOR ATHEROSCLEROSIS. ATHEROSCLEROSIS IS A COMPLEX METABOLIC DISEASE CHARACTERIZED BY THE DYSFUNCTION OF LIPID METABOLISM AND CHRONIC INFLAMMATION IN THE INTIMAL SPACE OF THE VESSEL. AS THE MOST ABUNDANT INNATE IMMUNE CELLS, MONOCYTE-DERIVED MACROPHAGES PLAY A PIVOTAL ROLE IN THE INFLAMMATORY RESPONSE, CHOLESTEROL METABOLISM, AND FOAM CELL FORMATION. IN RECENT DECADES, IT HAS BEEN DEMONSTRATED THAT MONOCYTES AND MACROPHAGES CAN ESTABLISH INNATE IMMUNE MEMORY (ALSO TERMED TRAINED IMMUNITY) VIA ENDOGENOUS AND EXOGENOUS ATHEROGENIC STIMULI AND EXHIBIT A LONG-LASTING PROINFLAMMATORY PHENOTYPE. THE IMPORTANT CELLULAR METABOLISM PROCESSES, INCLUDING GLYCOLYSIS, OXIDATIVE PHOSPHORYLATION (OXPHOS), THE TRICARBOXYLIC ACID (TCA) CYCLE, FATTY ACID SYNTHESIS, AND CHOLESTEROL SYNTHESIS, ARE REPROGRAMMED. TRAINED MONOCYTES/MACROPHAGES WITH INNATE IMMUNE MEMORY CAN BE PERSISTENTLY HYPERACTIVATED AND CAN UNDERGO EXTENSIVE EPIGENETIC REWIRING, WHICH CONTRIBUTES TO THE PATHOPHYSIOLOGICAL DEVELOPMENT OF ATHEROSCLEROSIS VIA INCREASED PROINFLAMMATORY CYTOKINE PRODUCTION AND LIPID ACCUMULATION. HERE, WE PROVIDE AN OVERVIEW OF THE REGULATION OF CELLULAR METABOLIC PROCESSES AND EPIGENETIC MODIFICATIONS OF INNATE IMMUNE MEMORY IN MONOCYTES/MACROPHAGES AS WELL AS THE POTENTIAL ENDOGENOUS AND EXOGENOUS STIMULATIONS INVOLVED IN THE PROGRESSION OF ATHEROSCLEROSIS THAT HAVE BEEN REPORTED RECENTLY. THESE ELUCIDATIONS MIGHT BE BENEFICIAL FOR FURTHER UNDERSTANDING INNATE IMMUNE MEMORY AND THE DEVELOPMENT OF THERAPEUTIC STRATEGIES FOR INFLAMMATORY DISEASES AND ATHEROSCLEROSIS. 2022