1 3393 177 HOST DETERMINANTS OF PRION STRAIN DIVERSITY INDEPENDENT OF PRION PROTEIN GENOTYPE. PHENOTYPIC DIVERSITY IN PRION DISEASES CAN BE SPECIFIED BY PRION STRAINS IN WHICH BIOLOGICAL TRAITS ARE PROPAGATED THROUGH AN EPIGENETIC MECHANISM MEDIATED BY DISTINCT PRP(SC) CONFORMATIONS. WE INVESTIGATED THE ROLE OF HOST-DEPENDENT FACTORS ON PHENOTYPIC DIVERSITY OF CHRONIC WASTING DISEASE (CWD) IN DIFFERENT HOST SPECIES THAT EXPRESS THE SAME PRION PROTEIN GENE (PRNP). TWO CWD STRAINS THAT HAVE DISTINCT BIOLOGICAL, BIOCHEMICAL, AND PATHOLOGICAL FEATURES WERE IDENTIFIED IN TRANSGENIC MICE THAT EXPRESS THE SYRIAN GOLDEN HAMSTER (SGH) PRNP. THE CKY STRAIN OF CWD HAD A SHORTER INCUBATION PERIOD THAN THE WST STRAIN OF CWD, BUT AFTER TRANSMISSION TO SGH, THE INCUBATION PERIOD OF CKY CWD WAS APPROXIMATELY 150 DAYS LONGER THAN WST CWD. LIMITED PROTEINASE K DIGESTION REVEALED STRAIN-SPECIFIC PRP(SC) POLYPEPTIDE PATTERNS THAT WERE MAINTAINED IN BOTH HOSTS, BUT THE SOLUBILITY AND CONFORMATIONAL STABILITY OF PRP(SC) DIFFERED FOR THE CWD STRAINS IN A HOST-DEPENDENT MANNER. WST CWD PRODUCED PRP(SC) AMYLOID PLAQUES IN THE BRAIN OF THE SGH THAT WERE PARTIALLY INSOLUBLE AND STABLE AT A HIGH CONCENTRATION OF PROTEIN DENATURANT. HOWEVER, IN TRANSGENIC MICE, PRP(SC) FROM WST CWD DID NOT ASSEMBLE INTO PLAQUES, WAS HIGHLY SOLUBLE, AND HAD LOW CONFORMATIONAL STABILITY. SIMILAR STUDIES USING THE HY AND DY STRAINS OF TRANSMISSIBLE MINK ENCEPHALOPATHY RESULTED IN MINOR DIFFERENCES IN PRION BIOLOGICAL AND PRP(SC) PROPERTIES BETWEEN TRANSGENIC MICE AND SGH. THESE FINDINGS INDICATE THAT HOST-SPECIFIC PATHWAYS THAT ARE INDEPENDENT OF PRNP CAN ALTER THE PRP(SC) CONFORMATION OF CERTAIN PRION STRAINS, LEADING TO CHANGES IN THE BIOPHYSICAL PROPERTIES OF PRP(SC), NEUROPATHOLOGY, AND CLINICAL PRION DISEASE. IMPORTANCE: PRIONS ARE MISFOLDED PATHOGENIC PROTEINS THAT CAUSE NEURODEGENERATION IN HUMANS AND ANIMALS. TRANSMISSIBLE PRION DISEASES EXHIBIT A SPECTRUM OF DISEASE PHENOTYPES AND THE BASIS OF THIS DIVERSITY IS ENCODED IN THE STRUCTURE OF THE PATHOGENIC PRION PROTEIN AND PROPAGATED BY AN EPIGENETIC MECHANISM. IN THE PRESENT STUDY, WE INVESTIGATED PRION DIVERSITY IN TWO HOSTS SPECIES THAT EXPRESS THE SAME PRION PROTEIN GENE. WHILE PRIOR REPORTS HAVE DEMONSTRATED THAT PRION STRAIN PROPERTIES ARE STABLE UPON INFECTION OF THE SAME HOST SPECIES AND PRION PROTEIN GENOTYPE, OUR FINDINGS INDICATE THAT CERTAIN PRION STRAINS CAN UNDERGO DRAMATIC CHANGES IN BIOLOGICAL PROPERTIES THAT ARE NOT DEPENDENT ON THE PRION PROTEIN. THEREFORE, HOST FACTORS INDEPENDENT OF THE PRION PROTEIN CAN AFFECT PRION DIVERSITY. UNDERSTANDING HOW HOST PATHWAYS CAN MODIFY PRION DISEASE PHENOTYPES MAY PROVIDE CLUES ON HOW TO ALTER PRION FORMATION AND LEAD TO TREATMENTS FOR PRION, AND OTHER, HUMAN NEURODEGENERATIVE DISEASES OF PROTEIN MISFOLDING. 2015 2 1156 50 CONSIDERING THE USE OF THE TERMS STRAIN AND ADAPTATION IN PRION RESEARCH. EVOLUTIONARY BIOLOGISTS AND DISEASE BIOLOGISTS USE THE TERMS STRAIN AND ADAPTATION IN CHRONIC WASTING DISEASE (CWD) RESEARCH IN DIFFERENT WAYS. IN EVOLUTIONARY BIOLOGY, A STRAIN IS A NASCENT GENETIC LINEAGE THAT CAN BE DESCRIBED BY A GENEALOGY, AND A PHYLOGENETIC NOMENCLATURE CONSTRUCTED TO REFLECT THAT GENEALOGY. PRION STRAINS ARE DESCRIBED AS SHOWING DISTINCT HOST RANGE, CLINICAL PRESENTATION, DISEASE PROGRESSION, AND NEUROPATHOLOGICAL AND PRP BIOCHEMICAL PROFILES, AND LACK INFORMATION THAT WOULD PERMIT PHYLOGENETIC RECONSTRUCTION OF THEIR HISTORY. PRION STRAINS ARE ALTERNATIVE PROTEIN CONFORMATIONS, SOMETIMES DERIVED FROM THE SAME GENOTYPE. I SUGGEST REFERRING TO PRION STRAINS AS ECOTYPES, BECAUSE THE VARIANT PHENOTYPIC CONFORMATIONS ("STRAINS") ARE A FUNCTION OF THE INTERACTION BETWEEN PRNP AMINO ACID GENOTYPE AND THE HOST ENVIRONMENT. IN THE CASE OF CWD, A PRION ECOTYPE IN WHITE-TAILED DEER WOULD BE DESCRIBED BY ITS GENOTYPE AND THE HOST IN WHICH IT OCCURS, SUCH AS THE H95 + ECOTYPE. HOWEVER, AN EVOLUTIONARY NOMENCLATURE IS DIFFICULT BECAUSE NOT ALL INDIVIDUALS WITH THE SAME PRNP GENOTYPE SHOW SIGNS OF CWD, THEREFORE CREATING A NOMENCLATURE REFLECTING AND ONE-TO-ONE RELATIONSHIP BETWEEN PRNP GENEALOGY AND CWD PRESENCE IS DIFFICULT. FURTHERMORE, VERY LITTLE INFORMATION EXISTS ON THE PHYLOGENETIC DISTRIBUTION OF CWD ECOTYPES IN WILD DEER POPULATIONS. ADAPTATION HAS A CLEAR MEANING IN EVOLUTIONARY BIOLOGY, THE DIFFERENTIAL SURVIVAL AND REPRODUCTION OF INDIVIDUAL GENOTYPES. IF A NEW PRION ECOTYPE ARISES IN A PARTICULAR HOST AND KILLS MORE HOSTS OR KILLS AT AN EARLIER AGE, IT IS THE ANTITHESIS OF THE EVOLUTIONARY DEFINITION OF ADAPTATION. HOWEVER, PRION STRAINS MIGHT BE TRANSMITTED ACROSS GENERATIONS EPIGENETICALLY, BUT WHETHER THIS REPRESENTS ADAPTATION DEPENDS ON THE FITNESS CONSEQUENCES OF THE STRAIN. PROTEIN PHENOTYPES OF PRNP THAT CAUSE TRANSMISSIBLE SPONGIFORM ENCEPHALOPATHIES (TSES), AND CWD, ARE MALADAPTIVE AND WOULD NOT BE PROPAGATED GENETICALLY OR EPIGENETICALLY VIA A PROCESS CONSISTENT WITH AN EVOLUTIONARY VIEW OF ADAPTATION. I SUGGEST TERMING THE PROCESS OF PRION STRAIN ORIGINATION "PHENOTYPIC TRANSFORMATION", AND ONLY ADAPTATION IF EVIDENCE SHOWS THEY ARE NOT MALADAPTIVE AND PERSIST OVER EVOLUTIONARY TIME PERIODS (E.G., THOUSANDS OF GENERATIONS) AND ACROSS DISTINCT SPECIES BOUNDARIES (VIA INHERITANCE). THUS, PRION BIOLOGISTS USE STRAIN AND ADAPTATION, HISTORICALLY EVOLUTIONARY TERMS, IN QUITE DIFFERENT WAYS. 2021 3 5464 36 RESILIENCE IN LONG-TERM VIRAL INFECTION: GENETIC DETERMINANTS AND INTERACTIONS. VIRUS-INDUCED NEUROLOGICAL SEQUELAE RESULTING FROM INFECTION BY THEILER'S MURINE ENCEPHALOMYELITIS VIRUS (TMEV) ARE USED FOR STUDYING HUMAN CONDITIONS RANGING FROM EPILEPTIC SEIZURES TO DEMYELINATING DISEASE. MOUSE STRAINS ARE TYPICALLY CONSIDERED SUSCEPTIBLE OR RESISTANT TO TMEV INFECTION BASED ON VIRAL PERSISTENCE AND EXTREME PHENOTYPES, SUCH AS DEMYELINATION. WE HAVE IDENTIFIED A BROADER SPECTRUM OF PHENOTYPIC OUTCOMES BY INFECTING STRAINS OF THE GENETICALLY DIVERSE COLLABORATIVE CROSS (CC) MOUSE RESOURCE. WE EVALUATED THE CHRONIC-INFECTION GENE EXPRESSION PROFILES OF HIPPOCAMPI AND THORACIC SPINAL CORDS FOR 19 CC STRAINS IN RELATION TO PHENOTYPIC SEVERITY AND TMEV PERSISTENCE. STRAINS WERE CLUSTERED BASED ON SIMILAR PHENOTYPIC PROFILES AND TMEV LEVELS AT 90 DAYS POST-INFECTION, AND WE CATEGORIZED DISTINCT TMEV RESPONSE PROFILES. THE THREE MOST COMMON PROFILES INCLUDED "RESISTANT" AND "SUSCEPTIBLE," AS BEFORE, AS WELL AS A "RESILIENT" TMEV RESPONSE GROUP WHICH EXPERIENCED BOTH TMEV PERSISTENCE AND MILD NEUROLOGICAL PHENOTYPES EVEN AT 90 DAYS POST-INFECTION. EACH PROFILE HAD A DISTINCT GENE EXPRESSION SIGNATURE, ALLOWING THE IDENTIFICATION OF PATHWAYS AND NETWORKS SPECIFIC TO EACH TMEV RESPONSE GROUP. CC FOUNDER HAPLOTYPES FOR GENES INVOLVED IN THESE PATHWAYS/NETWORKS REVEALED CANDIDATE RESPONSE-SPECIFIC ALLELES. THESE ALLELES DEMONSTRATED PLEIOTROPY AND EPIGENETIC (MIRNA) REGULATION IN LONG-TERM TMEV INFECTION, WITH PARTICULAR RELEVANCE FOR RESILIENT MOUSE STRAINS. 2021 4 1162 40 CONTRASTING EFFECTS OF ACUTE AND CHRONIC STRESS ON THE TRANSCRIPTOME, EPIGENOME, AND IMMUNE RESPONSE OF ATLANTIC SALMON. STRESS EXPERIENCED DURING EARLY LIFE MAY HAVE LASTING EFFECTS ON THE IMMUNE SYSTEM, WITH IMPACTS ON HEALTH AND DISEASE DEPENDENT ON THE NATURE AND DURATION OF THE STRESSOR. THE EPIGENOME IS ESPECIALLY SENSITIVE TO ENVIRONMENTAL STIMULI DURING EARLY LIFE AND REPRESENTS A POTENTIAL MECHANISM THROUGH WHICH STRESS MAY CAUSE LONG-LASTING HEALTH EFFECTS. HOWEVER, THE EXTENT TO WHICH THE EPIGENOME RESPONDS DIFFERENTLY TO CHRONIC VS ACUTE STRESSORS IS UNCLEAR, ESPECIALLY FOR NON-MAMMALIAN SPECIES. WE EXAMINED THE EFFECTS OF ACUTE STRESS (COLD-SHOCK DURING EMBRYOGENESIS) AND CHRONIC STRESS (ABSENCE OF TANK ENRICHMENT DURING LARVAL-STAGE) ON GLOBAL GENE EXPRESSION (USING RNA-SEQ) AND DNA METHYLATION (USING RRBS) IN THE GILLS OF ATLANTIC SALMON (SALMO SALAR) FOUR MONTHS AFTER HATCHING. CHRONIC STRESS INDUCED PRONOUNCED TRANSCRIPTIONAL DIFFERENCES, WHILE ACUTE STRESS CAUSED FEW LASTING TRANSCRIPTIONAL EFFECTS. HOWEVER, BOTH ACUTE AND CHRONIC STRESS CAUSED LASTING AND CONTRASTING CHANGES IN THE METHYLOME. CRUCIALLY, WE FOUND THAT ACUTE STRESS ENHANCED TRANSCRIPTIONAL IMMUNE RESPONSE TO A PATHOGENIC CHALLENGE (BACTERIAL LIPOPOLYSACCHARIDE, LPS), WHILE CHRONIC STRESS SUPPRESSED IT. WE IDENTIFIED STRESS-INDUCED CHANGES IN PROMOTER AND GENE-BODY METHYLATION THAT WERE ASSOCIATED WITH ALTERED EXPRESSION FOR A SMALL PROPORTION OF IMMUNE-RELATED GENES, AND EVIDENCE OF WIDER EPIGENETIC REGULATION WITHIN SIGNALLING PATHWAYS INVOLVED IN IMMUNE RESPONSE. OUR RESULTS SUGGEST THAT STRESS CAN AFFECT IMMUNO-COMPETENCE THROUGH EPIGENETIC MECHANISMS, AND HIGHLIGHT THE MARKEDLY DIFFERENT EFFECTS OF CHRONIC LARVAL AND ACUTE EMBRYONIC STRESS. THIS KNOWLEDGE COULD BE USED TO HARNESS THE STIMULATORY EFFECTS OF ACUTE STRESS ON IMMUNITY, PAVING THE WAY FOR IMPROVED STRESS AND DISEASE MANAGEMENT THROUGH EPIGENETIC CONDITIONING. 2018 5 1182 49 CONVERGING AND DIFFERENTIAL BRAIN PHOSPHOLIPID DYSREGULATION IN THE PATHOGENESIS OF REPETITIVE MILD TRAUMATIC BRAIN INJURY AND ALZHEIMER'S DISEASE. REPETITIVE MILD TRAUMATIC BRAIN INJURY (RMTBI) IS A MAJOR EPIGENETIC RISK FACTOR FOR ALZHEIMER'S DISEASE (AD). THE PRECISE NATURE OF HOW RMTBI LEADS TO OR PRECIPITATES AD PATHOLOGY IS CURRENTLY UNKNOWN. NUMEROUS NEUROLOGICAL CONDITIONS HAVE SHOWN AN IMPORTANT ROLE FOR DYSFUNCTIONAL PHOSPHOLIPID METABOLISM AS A DRIVING FACTOR FOR THE PATHOGENESIS OF NEURODEGENERATIVE DISEASES. HOWEVER, THE PRECISE ROLE IN RMTBI AND AD REMAINS ELUSIVE. WE HYPOTHESIZED THAT A DETAILED PHOSPHOLIPID CHARACTERIZATION WOULD REVEAL PROFILES OF RESPONSE TO INJURY IN TBI THAT OVERLAP WITH AGE-DEPENDENT CHANGES IN AD AND THUS PROVIDE INSIGHTS INTO THE TBI-AD RELATIONSHIP. WE EMPLOYED A LIPIDOMIC APPROACH EXAMINING BRAIN PHOSPHOLIPID PROFILES FROM MOUSE MODELS OF RMTBI AND AD. CORTEX AND HIPPOCAMPAL TISSUE WERE COLLECTED AT 24 H, 3, 6, 9, AND 12 MONTHS POST-RMTBI, AND AT AGES REPRESENTING 'PRE', 'PERI' AND 'POST' ONSET OF AMYLOID PATHOLOGY (I.E., 3, 9, 15 MONTHS-OLD). TOTAL LEVELS OF PHOSPHATIDYLCHOLINE (PC), PHOSPHATIDYLETHANOLAMINE (PE), LYSOPE, AND PHOSPHATIDYLINOSITOL (PI), INCLUDING THEIR MONOUNSATURATED, POLYUNSATURATED AND SATURATED FATTY ACID (FA) CONTAINING SPECIES WERE SIGNIFICANTLY INCREASED AT ACUTE AND/OR CHRONIC TIME POINTS POST-INJURY IN BOTH BRAIN REGIONS. HOWEVER, LEVELS OF MOST PHOSPHOLIPID SPECIES IN PS1/APP MICE WERE NOMINAL IN THE HIPPOCAMPUS, WHILE IN THE CORTEX, LEVELS WERE SIGNIFICANTLY DECREASED AT AGES POST-ONSET OF AMYLOID PATHOLOGY. SPHINGOMYELIN AND LYSOPC LEVELS SHOWED COINCIDENTAL TRENDS IN OUR RMTBI AND AD MODELS WITHIN THE HIPPOCAMPUS, AN INCREASE AT ACUTE AND/OR CHRONIC TIME POINTS EXAMINED. THE RATIO OF ARACHIDONIC ACID (OMEGA-6 FA) TO DOCOSAHEXAENOIC ACID (OMEGA-3 FA)-CONTAINING PE SPECIES WAS INCREASED AT EARLY TIME POINTS IN THE HIPPOCAMPUS OF INJURED VERSUS SHAM MICE, AND IN PS1/APP MICE THERE WAS A COINCIDENTAL INCREASE COMPARED TO WILD TYPE LITTERMATES AT ALL TIME POINTS. THIS STUDY DEMONSTRATES SOME OVERLAPPING AND DIVERSE PHOSPHOLIPID PROFILES IN RMTBI AND AD MODELS. FUTURE STUDIES ARE REQUIRED TO CORROBORATE OUR FINDINGS IN HUMAN POST-MORTEM TISSUE. INVESTIGATION OF SECONDARY MECHANISMS TRIGGERED BY ABERRANT DOWNSTREAM ALTERATIONS IN BIOACTIVE METABOLITES OF THESE PHOSPHOLIPIDS, AND THEIR MODULATION AT THE APPROPRIATE TIME-WINDOWS OF OPPORTUNITY COULD HELP FACILITATE DEVELOPMENT OF NOVEL THERAPEUTIC STRATEGIES TO AMELIORATE THE NEURODEGENERATIVE CONSEQUENCES OF RMTBI OR THE POTENTIAL TRIGGERING OF AD PATHOGENESIS BY RMTBI. 2019 6 1174 37 CONTRIBUTION OF TRANSPOSABLE ELEMENTS TO TRANSGENERATIONAL EFFECTS OF CHRONIC RADIOACTIVE EXPOSURE OF NATURAL POPULATIONS OF DROSOPHILA MELANOGASTER LIVING FOR A LONG TIME IN THE ZONE OF THE CHERNOBYL NUCLEAR DISASTER. THE ACCIDENT AT THE CHERNOBYL NUCLEAR POWER PLANT (CHNPP) LED TO THE NEGATIVE IMPACT OF CHRONIC RADIOACTIVE CONTAMINATION ON POPULATIONS OF ORGANISMS ASSOCIATED WITH THE TRANSGENERATIONAL TRANSMISSION OF GENOME INSTABILITY. WHEN THE DESTABILIZATION OF GENOME, DIFFERENT GENETIC DAMAGES OCCUR, THE ACCUMULATION OF WHICH LEADS TO THE FORMATION OF MUTATIONS, MORPHOLOGICAL ANOMALIES, AND MORTALITY IN THE OFFSPRING. THE MECHANISMS UNDERLYING THE MANIFESTATION OF TRANSGENERATIONAL EVENTS IN THE OFFSPRING OF IRRADIATED PARENTS ARE NOT WELL UNDERSTOOD. IN THIS STUDY, FOR THE FIRST TIME, THE FEATURES OF THE INFLUENCE OF TRANSPOSABLE ELEMENTS (TES) ON THE LONG-TERM BIOLOGICAL CONSEQUENCES OF THE CHNPP ARE CONSIDERED. IN THIS WORK, SPECIMENS OF D. MELANOGASTER OBTAINED FROM NATURAL POPULATIONS IN 2007 IN THE AREAS OF THE CHNPP WITH HETEROGENEOUS RADIOACTIVE CONTAMINATION WERE STUDIED. THE DESCENDANTS FROM THESE POPULATIONS WERE MAINTAINED IN LABORATORY (INBRED) CONDITIONS FOR 160 GENERATIONS. A STABLE TRANSGENERATIONAL TRANSMISSION OF DOMINANT LETHAL MUTATIONS (DLMS) TO THE OFFSPRING OF ALL STUDIED POPULATIONS WAS SHOWN. THE DLM FREQUENCIES STRONGLY WERE CORRELATED WITH THE LEVEL OF SURVIVAL OF OFFSPRING. THE MEAN FREQUENCIES OF RECESSIVE SEX-LINKED LETHAL MUTATIONS VARIED AT THE LEVEL OF SPONTANEOUS POINT MUTATIONS. THE SIMULTANEOUS PRESENCE OF P, HOBO AND I ELEMENTS INDICATES THAT THE STUDIED POPULATIONS DO NOT HAVE A DEFINITE CYTOTYPE, THEIR PHENOTYPIC STATUS IS UNSTABLE. THE BEHAVIOR OF TES IN THE GENOMES OF OFFSPRING DEPENDS NOT ONLY ON PARENTAL EXPOSURE, BUT ALSO ON ORIGIN OF POPULATION, DISTANCE TO THE CHNPP, AND INBRED CONDITIONS. THE OBTAINED RESULTS CONFIRM THE HYPOTHESIS THAT TES ARE INVOLVED IN TRANSGENERATIONAL TRANSMISSION AND ACCUMULATION OF MUTATIONS BY THE OFFSPRING OF IRRADIATED PARENTS. THE TES PATTERN PRESENT IN THE CHERNOBYL GENOMES OF D. MELANOGASTER IS A PECULIAR OF EPIGENETIC MECHANISM FOR THE REGULATION OF PLASTICITY AND ADAPTATION OF POPULATIONS LIVING FOR MANY GENERATIONS UNDER CONDITIONS OF A TECHNOGENICALLY CAUSED RADIATION BACKGROUND. 2022 7 3736 46 INNATE IMMUNE TOLERANCE IN MICROGLIA DOES NOT IMPACT ON CENTRAL NERVOUS SYSTEM PRION DISEASE. PRION DISEASES SUCH AS CREUTZFELDT-JAKOB DISEASE IN HUMANS, BOVINE SPONGIFORM ENCEPHALOPATHY IN CATTLE, AND SCRAPIE IN SHEEP, ARE INFECTIOUS AND CHRONIC NEURODEGENERATIVE DISEASES TO WHICH THERE ARE NO CURES. INFECTION WITH PRIONS IN THE CENTRAL NERVOUS SYSTEM (CNS) ULTIMATELY CAUSES EXTENSIVE NEURODEGENERATION, AND THIS IS ACCOMPANIED BY PROMINENT MICROGLIAL AND ASTROCYTIC ACTIVATION IN AFFECTED REGIONS. THE MICROGLIA ARE THE CNS MACROPHAGES AND HELP MAINTAIN NEURONAL HOMEOSTASIS, CLEAR DEAD OR DYING CELLS AND PROVIDE DEFENSE AGAINST PATHOGENS. THE MICROGLIA ALSO PROVIDE NEUROPROTECTION DURING CNS PRION DISEASE, BUT THEIR PRO-INFLAMMATORY ACTIVATION MAY EXACERBATE THE DEVELOPMENT OF THE NEUROPATHOLOGY. INNATE IMMUNE TOLERANCE INDUCED BY CONSECUTIVE SYSTEMIC BACTERIAL LIPOPOLYSACCHARIDE (LPS) TREATMENT CAN INDUCE LONG-TERM EPIGENETIC CHANGES IN THE MICROGLIA IN THE BRAIN THAT SEVERAL MONTHS LATER CAN DAMPEN THEIR RESPONSIVENESS TO SUBSEQUENT LPS TREATMENT AND IMPEDE THE DEVELOPMENT OF NEURITIC DAMAGE IN A TRANSGENIC MOUSE MODEL OF ALZHEIMER'S DISEASE-LIKE PATHOLOGY. WE THEREFORE REASONED THAT INNATE IMMUNE TOLERANCE IN MICROGLIA MIGHT SIMILARLY IMPEDE THE SUBSEQUENT DEVELOPMENT OF CNS PRION DISEASE. TO TEST THIS HYPOTHESIS GROUPS OF MICE WERE FIRST INFECTED WITH PRIONS BY INTRACEREBRAL INJECTION, AND 35 DAYS LATER GIVEN FOUR CONSECUTIVE SYSTEMIC INJECTIONS WITH LPS TO INDUCE INNATE IMMUNE TOLERANCE. OUR DATA SHOW THAT CONSECUTIVE SYSTEMIC LPS TREATMENT DID NOT AFFECT THE SUBSEQUENT DEVELOPMENT OF CNS PRION DISEASE. OUR DATA SUGGESTS INNATE IMMUNE TOLERANCE IN MICROGLIA DOES NOT INFLUENCE THE SUBSEQUENT ONSET OF PRION DISEASE-INDUCED NEUROPATHOLOGY IN MICE, DESPITE PREVIOUSLY PUBLISHED EVIDENCE OF THIS EFFECT IN AN ALZHEIMER'S DISEASE MOUSE MODEL. 2022 8 2246 29 EPIGENETIC MODULATION OF INFLAMMATION AND SYNAPTIC PLASTICITY PROMOTES RESILIENCE AGAINST STRESS IN MICE. MAJOR DEPRESSIVE DISORDER IS ASSOCIATED WITH ABNORMALITIES IN THE BRAIN AND THE IMMUNE SYSTEM. CHRONIC STRESS IN ANIMALS SHOWED THAT EPIGENETIC AND INFLAMMATORY MECHANISMS PLAY IMPORTANT ROLES IN MEDIATING RESILIENCE AND SUSCEPTIBILITY TO DEPRESSION. HERE, THROUGH A HIGH-THROUGHPUT SCREENING, WE IDENTIFY TWO PHYTOCHEMICALS, DIHYDROCAFFEIC ACID (DHCA) AND MALVIDIN-3'-O-GLUCOSIDE (MAL-GLUC) THAT ARE EFFECTIVE IN PROMOTING RESILIENCE AGAINST STRESS BY MODULATING BRAIN SYNAPTIC PLASTICITY AND PERIPHERAL INFLAMMATION. DHCA/MAL-GLUC ALSO SIGNIFICANTLY REDUCES DEPRESSION-LIKE PHENOTYPES IN A MOUSE MODEL OF INCREASED SYSTEMIC INFLAMMATION INDUCED BY TRANSPLANTATION OF HEMATOPOIETIC PROGENITOR CELLS FROM STRESS-SUSCEPTIBLE MICE. DHCA REDUCES PRO-INFLAMMATORY INTERLEUKIN 6 (IL-6) GENERATIONS BY INHIBITING DNA METHYLATION AT THE CPG-RICH IL-6 SEQUENCES INTRONS 1 AND 3, WHILE MAL-GLUC MODULATES SYNAPTIC PLASTICITY BY INCREASING HISTONE ACETYLATION OF THE REGULATORY SEQUENCES OF THE RAC1 GENE. PERIPHERAL INFLAMMATION AND SYNAPTIC MALADAPTATION ARE IN LINE WITH NEWLY HYPOTHESIZED CLINICAL INTERVENTION TARGETS FOR DEPRESSION THAT ARE NOT ADDRESSED BY CURRENTLY AVAILABLE ANTIDEPRESSANTS. 2018 9 3899 31 LATE NEUROLOGICAL CONSEQUENCES OF ZIKA VIRUS INFECTION: RISK FACTORS AND PHARMACEUTICAL APPROACHES. ZIKA VIRUS (ZIKV) INFECTION WAS HISTORICALLY CONSIDERED A DISEASE WITH MILD SYMPTOMS AND NO MAJOR CONSEQUENCES TO HUMAN HEALTH. HOWEVER, SEVERAL LONG-TERM, LATE ONSET, AND CHRONIC NEUROLOGICAL COMPLICATIONS, BOTH IN CONGENITALLY-EXPOSED BABIES AND IN ADULT PATIENTS, HAVE BEEN REPORTED AFTER ZIKV INFECTION, ESPECIALLY AFTER THE 2015 EPIDEMICS IN THE AMERICAN CONTINENT. THE DEVELOPMENT OR SEVERITY OF THESE CONDITIONS CANNOT BE FULLY PREDICTED, BUT IT IS POSSIBLE THAT GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS MAY CONTRIBUTE TO DETERMINE ZIKV INFECTION OUTCOMES. THIS REINFORCES THE IMPORTANCE THAT INDIVIDUALS EXPOSED TO ZIKV ARE SUBMITTED TO LONG-TERM CLINICAL SURVEILLANCE AND HIGHLIGHTS THE URGENT NEED FOR THE DEVELOPMENT OF THERAPEUTIC APPROACHES TO REDUCE OR ELIMINATE THE NEUROLOGICAL BURDEN OF INFECTION. HERE, WE REVIEW THE EPIDEMIOLOGY OF ZIKV-ASSOCIATED NEUROLOGICAL COMPLICATIONS AND THE ROLE OF FACTORS THAT MAY INFLUENCE DISEASE OUTCOME. MOREOVER, WE DISCUSS EXPERIMENTAL AND CLINICAL EVIDENCE OF DRUGS THAT HAVE SHOWN PROMISING RESULTS IN VITRO OR IN VITRO AGAINST VIRAL REPLICATION AND AND/OR ZIKV-INDUCED NEUROTOXICITY. 2019 10 6137 30 THE EPIGENETICS OF PSYCHOSIS: A STRUCTURED REVIEW WITH REPRESENTATIVE LOCI. THE EVIDENCE FOR AN ENVIRONMENTAL COMPONENT IN CHRONIC PSYCHOTIC DISORDERS IS STRONG AND RESEARCH ON THE EPIGENETIC MANIFESTATIONS OF THESE ENVIRONMENTAL IMPACTS HAS COMMENCED IN EARNEST. IN REVIEWING THIS RESEARCH, THE FOCUS IS ON THREE GENES AS MODELS FOR DIFFERENTIAL METHYLATION, MCHR1, AKT1 AND TDO2, EACH OF WHICH HAVE BEEN INVESTIGATED FOR GENETIC ASSOCIATION WITH PSYCHOTIC DISORDERS. ENVIRONMENTAL FACTORS ASSOCIATED WITH PSYCHOTIC DISORDERS, AND WHICH INTERACT WITH THESE MODEL GENES, ARE EXPLORED IN DEPTH. THE LOCATION OF TRANSCRIPTION FACTOR MOTIFS RELATIVE TO KEY METHYLATION SITES IS EVALUATED FOR PREDICTED GENE EXPRESSION RESULTS, AND FOR OTHER SITES, EVIDENCE IS PRESENTED FOR METHYLATION DIRECTING ALTERNATIVE SPLICING. EXPERIMENTAL RESULTS FROM KEY STUDIES SHOW DIFFERENTIAL METHYLATION: FOR MCHR1, IN PSYCHOSIS CASES VERSUS CONTROLS; FOR AKT1, AS A PRE-EXISTING METHYLATION PATTERN INFLUENCING BRAIN ACTIVATION FOLLOWING ACUTE ADMINISTRATION OF A PSYCHOSIS-ELICITING ENVIRONMENTAL STIMULUS; AND FOR TDO2, IN A PATTERN ASSOCIATED WITH A DEVELOPMENTAL FACTOR OF RISK FOR PSYCHOSIS, IN ALL CASES THE PREDICTED EXPRESSION IMPACT BEING HIGHLY DEPENDENT ON LOCATION. METHYLATION INDUCED BY SMOKING, A CONFOUNDING VARIABLE, EXHIBITS AN INTRIGUING PATTERN FOR ALL THREE GENES. FINALLY, HOW DIFFERENTIAL METHYLATION MESHES WITH DARWINIAN PRINCIPLES IS EXAMINED, IN PARTICULAR AS IT RELATES TO THE "FLEXIBLE STEM" THEORY OF EVOLUTION. 2022 11 3465 48 HYPOTHESIS: REGULATION OF NEUROPLASTICITY MAY INVOLVE I-MOTIF AND G-QUADRUPLEX DNA FORMATION MODULATED BY EPIGENETIC MECHANISMS. RECENT STUDIES DEMONSTRATED THE EXISTENCE IN VIVO OF VARIOUS FUNCTIONAL DNA STRUCTURES THAT DIFFER FROM THE DOUBLE HELIX. THE G-QUADRUPLEX (G4) AND INTERCALATED MOTIF (I-MOTIF OR IM) DNA STRUCTURES ARE FORMED AS KNOTS WHERE, CORRESPONDINGLY, GUANINES OR CYTOSINES ON THE SAME STRAND OF DNA BIND TO EACH OTHER. THERE ARE GROUNDS TO BELIEVE THAT G4 AND IM SEQUENCES PLAY A SIGNIFICANT ROLE IN REGULATING GENE EXPRESSION CONSIDERING THEIR TENDENCY TO BE FOUND IN OR NEAR REGULATORY SITES (SUCH AS PROMOTERS, ENHANCERS, AND TELOMERES) AS WELL AS THE CORRELATION BETWEEN THE PREVALENCE OF G4 OR IM CONFORMATIONS AND SPECIFIC PHASES OF CELL CYCLE. NOTABLY, G4 AND IM CAPABLE SEQUENCES TEND TO BE FOUND ON THE OPPOSITE STRANDS OF THE SAME DNA SITE WITH AT MOST ONE OF THE TWO STRUCTURES FORMED AT ANY GIVEN TIME. THE RECENT EVIDENCE THAT K(+), MG(2+) CONCENTRATIONS DIRECTLY AFFECT IM FORMATION (AND LIKELY G4 FORMATION INDIRECTLY) LEAD US TO BELIEVE THAT THESE STRUCTURES MAY PLAY A MAJOR ROLE IN SYNAPTIC PLASTICITY OF NEURONS, AND, THEREFORE, IN A VARIETY OF CENTRAL NERVOUS SYSTEM (CNS) FUNCTIONS INCLUDING MEMORY, LEARNING, HABITUAL BEHAVIORS, PAIN PERCEPTION AND OTHERS. FURTHERMORE, EPIGENETIC MECHANISMS, WHICH HAVE AN IMPORTANT ROLE IN SYNAPTIC PLASTICITY AND MEMORY FORMATION, WERE ALSO SHOWN TO INFLUENCE FORMATION AND STABILITY OF G4S AND IMS. OUR HYPOTHESIS IS THAT NON-CANONICAL DNA AND RNA STRUCTURES COULD BE AN INTEGRAL PART OF NEUROPLASTICITY CONTROL VIA GENE EXPRESSION REGULATION AT THE LEVEL OF TRANSCRIPTION, TRANSLATION AND SPLICING. WE PROPOSE THAT THE REGULATORY ACTIVITY OF DNA IM AND G4 STRUCTURES IS MODULATED BY DNA METHYLATION/DEMETHYLATION OF THE IM AND/OR G4 SEQUENCES, WHICH FACILITATES THE SWITCH BETWEEN CANONICAL AND NON-CANONICAL CONFORMATION. OTHER NEURONAL MECHANISMS INTERACTING WITH THE FORMATION AND REGULATORY ACTIVITY OF NON-CANONICAL DNA AND RNA STRUCTURES, PARTICULARLY G4, IM AND TRIPLEXES, MAY INVOLVE MICRORNAS AS WELL AS ION AND PROTON FLUXES. WE ARE PROPOSING EXPERIMENTS IN ACUTE BRAIN SLICES AND IN VIVO TO TEST OUR HYPOTHESIS. THE PROPOSED STUDIES WOULD PROVIDE NEW INSIGHTS INTO FUNDAMENTAL NEURONAL MECHANISMS IN HEALTH AND DISEASE AND POTENTIALLY OPEN NEW AVENUES FOR TREATING MENTAL HEALTH DISORDERS. 2019 12 491 34 ASSESSING THE IMPACT OF POLYETHYLENE NANO/MICROPLASTIC EXPOSURE ON HUMAN VAGINAL KERATINOCYTES. THE GLOBAL RISE OF SINGLE-USE THROW-AWAY PLASTIC PRODUCTS HAS ELICITED A MASSIVE INCREASE IN THE NANO/MICROPLASTICS (N/MPLS) EXPOSURE BURDEN IN HUMANS. RECENTLY, IT HAS BEEN DEMONSTRATED THAT DISPOSABLE PERIOD PRODUCTS MAY RELEASE N/MPLS WITH USAGE, WHICH REPRESENTS A POTENTIAL THREAT TO WOMEN'S HEALTH WHICH HAS NOT BEEN SCIENTIFICALLY ADDRESSED YET. BY USING POLYETHYL ENE (PE) PARTICLES (200 NM TO 9 MUM), WE SHOWED THAT ACUTE EXPOSURE TO A HIGH CONCENTRATION OF N/MPLS INDUCED CELL TOXICITY IN VAGINAL KERATINOCYTES AFTER EFFECTIVE CELLULAR UPTAKE, AS VIABILITY AND APOPTOSIS DATA SUGGEST, ALONG WITH TRANSMISSION ELECTRON MICROSCOPY (TEM) OBSERVATIONS. THE INTERNALISED N/MPLS ALTERED THE EXPRESSION OF JUNCTIONAL AND ADHERENCE PROTEINS AND THE ORGANISATION OF THE ACTIN CORTEX, INFLUENCING THE LEVEL OF GENES INVOLVED IN OXIDATIVE STRESS SIGNALLING PATHWAYS AND THAT OF MIRNAS RELATED TO EPITHELIAL BARRIER FUNCTION. WHEN THE EXPOSURE TO PE N/MPLS WAS DISCONTINUED OR BECAME CHRONIC, CELLS WERE ABLE TO RECOVER FROM THE NEGATIVE EFFECTS ON VIABILITY AND DIFFERENTIATION/PROLIFERATION GENE EXPRESSION IN A FEW DAYS. HOWEVER, IN ALL CASES, PE N/MPL EXPOSURE PROMPTED A SUSTAINED ALTERATION OF DNA METHYLTRANSFERASE AND DNA DEMETHYLASE EXPRESSION, WHICH MIGHT IMPACT EPIGENETIC REGULATION PROCESSES, LEADING TO ACCELERATED CELL AGEING AND INFLAMMATION, OR THE OCCURRENCE OF MALIGNANT TRANSFORMATION. 2023 13 2776 47 EXTRAUTERINE GROWTH RESTRICTION ON PULMONARY VASCULAR ENDOTHELIAL DYSFUNCTION IN ADULT MALE RATS: THE ROLE OF EPIGENETIC MECHANISMS. OBJECTIVE: EARLY POSTNATAL LIFE IS CONSIDERED AS A CRITICAL TIME WINDOW FOR THE DETERMINATION OF LONG-TERM METABOLIC STATES AND ORGAN FUNCTIONS. EXTRAUTERINE GROWTH RESTRICTION (EUGR) CAUSES THE DEVELOPMENT OF ADULT-ONSET CHRONIC DISEASES, INCLUDING PULMONARY HYPERTENSION. HOWEVER, THE EFFECTS OF NUTRITIONAL DISADVANTAGES DURING THE EARLY POSTNATAL PERIOD ON PULMONARY VASCULAR CONSEQUENCES IN LATER LIFE ARE NOT FULLY UNDERSTOOD. OUR STUDY WAS DESIGNED TO TEST WHETHER EPIGENETICS DYSREGULATION MEDIATES THE CELLULAR MEMORY OF THIS EARLY POSTNATAL EVENT. METHODS AND RESULTS: TO TEST THIS HYPOTHESIS, WE ISOLATED PULMONARY VASCULAR ENDOTHELIAL CELLS BY MAGNETIC-ACTIVATED CELL SORTING FROM EUGR AND CONTROL RATS. A POSTNATAL INSULT, NUTRITIONAL RESTRICTION-INDUCED EUGR CAUSED DEVELOPMENT OF AN INCREASED PULMONARY ARTERY PRESSURE AT 9 WEEKS OF AGE IN MALE SPRAGUE-DAWLEY RATS. METHYL-DNA IMMUNE PRECIPITATION CHIP, GENOME-SCALE MAPPING STUDIES TO SEARCH FOR DIFFERENTIALLY METHYLATED LOCI BETWEEN CONTROL AND EUGR RATS, REVEALED SIGNIFICANT DIFFERENCE IN CYTOSINE METHYLATION BETWEEN EUGR AND CONTROL RATS. EUGR CHANGES THE CYTOSINE METHYLATION AT APPROXIMATELY 500 LOCI IN MALE RATS AT 9 WEEKS OF AGE, PRECEDING THE DEVELOPMENT OF PULMONARY HYPERTENSION AND THESE REPRESENT THE CANDIDATE LOCI FOR MEDIATING THE PATHOGENESIS OF PULMONARY VASCULAR DISEASE THAT OCCURS LATER IN LIFE. GENE ONTOLOGY ANALYSIS ON DIFFERENTIALLY METHYLATED GENES SHOWED THAT HYPERMETHYLATED GENES IN EUGR ARE VASCULAR DEVELOPMENT-ASSOCIATED GENES AND HYPOMETHYLATED GENES IN EUGR ARE LATE-DIFFERENTIATION-ASSOCIATED AND SIGNAL TRANSDUCTION GENES. WE VALIDATED CANDIDATE DYSREGULATED LOCI WITH THE QUANTITATIVE ASSAYS OF CYTOSINE METHYLATION AND GENE EXPRESSIONS. CONCLUSION: THESE RESULTS DEMONSTRATE THAT EPIGENETICS DYSREGULATION IS A STRONG MECHANISM FOR PROPAGATING THE CELLULAR MEMORY OF EARLY POSTNATAL EVENTS, CAUSING CHANGES IN THE EXPRESSION OF GENES AND LONG-TERM SUSCEPTIBILITY TO PULMONARY HYPERTENSION, AND FURTHER PROVIDING A NEW INSIGHT INTO THE PREVENTION AND TREATMENT OF EUGR-RELATED PULMONARY HYPERTENSION. 2014 14 3418 37 HUMAN HEALTH CONSEQUENCES OF ENVIRONMENTALLY-MODULATED GENE EXPRESSION: POTENTIAL ROLES OF ELF-EMF INDUCED EPIGENETIC VERSUS MUTAGENIC MECHANISMS OF DISEASE. IN ORDER TO DETERMINE IF THERE MIGHT BE BIOLOGICAL AND HEALTH CONSEQUENCES AFTER EXPOSURES TO EXTREMELY-LOW FREQUENCY ELECTROMAGNETIC FIELDS (ELF-EMF), EITHER EXPERIMENTALLY OR EPIDEMIOLOGICALLY, MECHANISTIC UNDERSTANDING OF THE POTENTIAL MEANS BY WHICH ANY ENVIRONMENTAL AGENT CAN AFFECT CELLS IN A MULTICELLULAR ORGANISM HAS TO BE REVIEWED. THE GOAL OF THIS LIMITED REVIEW IS TO DEMONSTRATE THAT, WHILE THE PREVAILING PARADIGM OF THE ENVIRONMENTALLY-INDUCED ACUTE AND CHRONIC DISEASES INVOLVES EITHER CELL KILLING (CYTOTOXICITY) OR GENE/CHROMOSOME MUTATIONS (GENOTOXICITY), ALTERATION OF THE EXPRESSION OF GENETIC INFORMATION AT THE TRANSCRIPTIONAL (TURNING GENES "ON" OR "OFF"), TRANSLATIONAL (STABILIZING OR DE-STABILIZING THE GENETIC MESSAGE), OR POSTTRANSLATIONAL (ALTERING THE GENE PRODUCT OR PROTEIN) LEVELS HAS THE POTENTIAL TO CONTRIBUTE TO VARIOUS DISEASES. THIS LATTER MECHANISM, "EPIGENETIC" TOXICITY, UNLIKE THE FORMER TWO WHICH ARE IRREVERSIBLE, IS CHARACTERIZED BY THRESHOLD-LIKE ACTION, MULTIPLE BIOCHEMICAL PATHWAYS AND CHRONIC, REGULAR EXPOSURES TO BE EFFECTIVE. ULTIMATELY, EPIGENETIC TOXICANTS AFFECT ONE OF FOUR POTENTIAL CELL STATES, NAMELY ALTERATION OF CELL PROLIFERATION, CELL DIFFERENTIATION, PROGRAMMED CELL DEATH (APOPTOSIS) OR ADAPTIVE RESPONSES OF DIFFERENTIATED CELLS. 2000 15 3591 21 IMPAIRED ONE CARBON METABOLISM AND DNA METHYLATION IN ALCOHOL TOXICITY. EXCESSIVE ALCOHOL CONSUMPTION IS A PROMINENT PROBLEM AND ONE OF THE MAJOR CAUSES OF MORTALITY AND MORBIDITY AROUND THE WORLD. LONG-TERM, HEAVY ALCOHOL CONSUMPTION IS ASSOCIATED WITH A NUMBER OF DELETERIOUS HEALTH CONSEQUENCES, SUCH AS CANCER, HEART AND LIVER DISEASE, A VARIETY OF NEUROLOGICAL, COGNITIVE, AND BEHAVIORAL DEFICITS. ALCOHOL CONSUMPTION IS ALSO ASSOCIATED WITH DEVELOPMENTAL DEFECTS. THE CAUSES OF ALCOHOL-INDUCED TOXICITY ARE PRESENTLY UNCLEAR. ONE OF THE MECHANISMS UNDERLYING ALCOHOL TOXICITY HAS TO DO WITH ITS INTERACTION WITH FOLIC ACID/HOMOCYSTEINE OR ONE-CARBON METABOLISM (OCM). OCM IS A MAJOR DONOR OF METHYL GROUPS FOR METHYLATION, PARTICULARLY DNA METHYLATION CRITICAL FOR EPIGENETIC REGULATION OF GENE EXPRESSION, AND ITS DISTURBANCE MAY COMPROMISE DNA METHYLATION, THEREBY AFFECTING GENE EXPRESSION. OCM DISTURBANCE MEDIATED BY NUTRIENT DEFICITS IS A WELL-KNOWN RISK FACTOR FOR VARIOUS DISORDERS AND DEVELOPMENTAL DEFECTS (E.G., NEURAL TUBE DEFECTS). IN THIS REVIEW, WE SUMMARIZE THE ROLE OF OCM DISTURBANCE AND ASSOCIATED EPIGENETIC ABERRATIONS IN CHRONIC ALCOHOL-INDUCED TOXICITY. IN THIS REVIEW, WE SUMMARIZE THE ROLE OF ONE-CARBON METABOLISM (OCM) ABERRATIONS IN CHRONIC ALCOHOL-INDUCED TOXICITY. OCM IS A MAJOR DONOR OF METHYL GROUPS FOR METHYLATION REACTIONS, PARTICULARLY DNA METHYLATION CRITICAL FOR EPIGENETIC REGULATION OF GENE EXPRESSION. ALCOHOL INTERFERENCE WITH OCM AND CONSEQUENT REDUCED AVAILABILITY OF METHYL GROUPS, IMPROPER DNA METHYLATION, AND ABERRANT GENE EXPRESSION CAN PLAY A CAUSATIVE ROLE IN ALCOHOL TOXICITY. 2014 16 6464 26 TISSUE MISREPAIR HYPOTHESIS FOR RADIATION CARCINOGENESIS. DOSE-RESPONSE CURVES FOR CHRONIC LEUKEMIA IN A-BOMB SURVIVORS AND LIVER TUMORS IN PATIENTS GIVEN THOROTRAST (COLLOIDAL THORIUM DIOXIDE) SHOW LARGE THRESHOLD EFFECTS. THE EXISTENCE OF THESE THRESHOLD EFFECTS CAN BE EXPLAINED BY THE FOLLOWING HYPOTHESIS. A HIGH DOSE OF RADIATION CAUSES A PERSISTENT WOUND IN A CELL-RENEWABLE TISSUE. DISORDER OF THE INJURED CELL SOCIETY PARTLY FREES THE COMPONENT CELLS FROM TERRITORIAL RESTRAINTS ON THEIR PROLIFERATION, ENABLING THEM TO CONTINUE DEVELOPMENT OF THEIR CELLULAR FUNCTIONS TOWARD ADVANCED AUTONOMY. THIS PROGRESSION MIGHT BE ACHIEVED BY CONTINUED EPIGENETIC AND GENETIC CHANGES AS A RESULT OF OCCASIONAL ERRORS IN THE OTHERWISE CONCERTED HEALING ACTION OF VARIOUS ENDOGENOUS FACTORS RECRUITED FOR TISSUE REPAIR. CARCINOGENESIS IS NOT SIMPLY A SINGLE-CELL PROBLEM BUT A CELL-SOCIETY PROBLEM. THEREFORE, IT IS NOT WARRANTED TO ESTIMATE RISK AT LOW DOSES BY LINEAR EXTRAPOLATION FROM CANCER DATA AT HIGH DOSES WITHOUT KNOWLEDGE OF THE MECHANISM OF RADIATION CARCINOGENESIS. 1991 17 2597 34 EPIGENETICS OF SUBCELLULAR STRUCTURE FUNCTIONING IN THE ORIGIN OF RISK OR RESILIENCE TO COMORBIDITY OF NEUROPSYCHIATRIC AND CARDIOMETABOLIC DISORDERS. MECHANISMS CONTROLLING MITOCHONDRIAL FUNCTION, PROTEIN FOLDING IN THE ENDOPLASMIC RETICULUM (ER) AND NUCLEAR PROCESSES SUCH AS TELOMERE LENGTH AND DNA REPAIR MAY BE SUBJECT TO EPIGENETIC CUES THAT RELATE THE GENOMIC EXPRESSION AND ENVIRONMENTAL EXPOSURES IN EARLY STAGES OF LIFE. THEY MAY ALSO BE INVOLVED IN THE COMORBID APPEARANCE OF CARDIOMETABOLIC (CMD) AND NEUROPSYCHIATRIC DISORDERS (NPD) DURING ADULTHOOD. MITOCHONDRIAL FUNCTION AND PROTEIN FOLDING IN THE ENDOPLASMIC RETICULUM ARE ASSOCIATED WITH OXIDATIVE STRESS AND ELEVATED INTRACELLULAR CALCIUM LEVELS AND MAY ALSO UNDERLIE THE VULNERABILITY FOR COMORBID CMD AND NPD. MITOCHONDRIA PROVIDE KEY METABOLITES SUCH AS NICOTINAMIDE ADENINE DINUCLEOTIDE (NAD+), ATP, ALPHA-KETOGLUTARATE AND ACETYL COENZYME A THAT ARE REQUIRED FOR MANY TRANSCRIPTIONAL AND EPIGENETIC PROCESSES. THEY ARE ALSO A SOURCE OF FREE RADICALS. ON THE OTHER HAND, EPIGENETIC MARKERS IN NUCLEAR DNA DETERMINE MITOCHONDRIAL BIOGENESIS. THE ER IS THE SUBCELLULAR ORGANELLE IN WHICH SECRETORY PROTEINS ARE FOLDED. MANY ENVIRONMENTAL FACTORS STOP THE ABILITY OF CELLS TO PROPERLY FOLD PROTEINS AND MODIFY POST-TRANSLATIONALLY SECRETORY AND TRANSMEMBRANE PROTEINS LEADING TO ENDOPLASMIC RETICULUM STRESS AND OXIDATIVE STRESS. ER FUNCTIONING MAY BE EPIGENETICALLY DETERMINED. CHRONIC ER STRESS IS EMERGING AS A KEY CONTRIBUTOR TO A GROWING LIST OF HUMAN DISEASES, INCLUDING CMD AND NPD. TELOMERE LOSS CAUSES CHROMOSOMAL FUSION, ACTIVATION OF THE CONTROL OF DNA DAMAGE-RESPONSES, UNSTABLE GENOME AND ALTERED STEM CELL FUNCTION, WHICH MAY UNDERLIE THE COMORBIDITY OF CMD AND NPD. THE LENGTH OF TELOMERES IS RELATED TO OXIDATIVE STRESS AND MAY BE EPIGENETICALLY PROGRAMMED. PATHWAYS INVOLVED IN DNA REPAIR MAY BE EPIGENETICALLY PROGRAMMED AND MAY CONTRIBUTE TO DISEASES. IN THIS PAPER, WE DESCRIBE SUBCELLULAR MECHANISMS THAT ARE DETERMINED BY EPIGENETIC MARKERS AND THEIR POSSIBLE RELATION TO THE DEVELOPMENT OF INCREASED SUSCEPTIBILITY TO DEVELOP CMD AND NPD. 2018 18 6642 29 UNRAVELING THE PATHOGENESIS OF ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE OVERLAP: FOCUSING ON EPIGENETIC MECHANISMS. ASTHMA AND COPD OVERLAP (ACO) IS CHARACTERIZED BY PATIENTS PRESENTING WITH PERSISTENT AIRFLOW LIMITATION AND FEATURES OF BOTH ASTHMA AND COPD. IT IS ASSOCIATED WITH A HIGHER FREQUENCY AND SEVERITY OF EXACERBATIONS, A FASTER LUNG FUNCTION DECLINE, AND A HIGHER HEALTHCARE COST. SYSTEMIC INFLAMMATION IN COPD AND ASTHMA IS DRIVEN BY TYPE 1 T HELPER (TH1) AND TH2 IMMUNE RESPONSES, RESPECTIVELY, BOTH OF WHICH MAY CONTRIBUTE TO AIRWAY REMODELING IN ACO. ACO-RELATED BIOMARKERS CAN BE CLASSIFIED INTO FOUR CATEGORIES: NEUTROPHIL-MEDIATED INFLAMMATION, TH2 CELL RESPONSES, ARACHIDONIC ACID-EICOSANOIDS PATHWAY, AND METABOLITES. GENE-ENVIRONMENT INTERACTIONS ARE KEY CONTRIBUTORS TO THE COMPLEXITY OF ACO AND ARE REGULATED BY EPIGENETIC MECHANISMS, INCLUDING DNA METHYLATION, HISTONE MODIFICATIONS, AND NON-CODING RNAS. THUS, THIS REVIEW FOCUSES ON THE LINK BETWEEN EPIGENETICS AND ACO, AND OUTLINES THE FOLLOWING: (I) INHERITING EPIGENOTYPES WITHOUT CHANGE WITH ENVIRONMENTAL STIMULI, OR EPIGENETIC CHANGES IN RESPONSE TO LONG-TERM EXPOSURE TO INHALED PARTICLES PLUS INTERMITTENT EXPOSURE TO SPECIFIC ALLERGENS; (II) EPIGENETIC MARKERS DISTINGUISHING ACO FROM COPD AND ASTHMA; (III) POTENTIAL EPIGENETIC DRUGS THAT CAN REVERSE OXIDATIVE STRESS, GLUCOCORTICOID INSENSITIVITY, AND CELL INJURY. IMPROVED UNDERSTANDING OF THE EPIGENETIC REGULATIONS HOLDS GREAT VALUE TO GIVE DEEPER INSIGHT INTO THE MECHANISMS, AND CLARIFY THEIR IMPLICATIONS FOR BIOMEDICAL RESEARCH IN ACO. 2022 19 4736 42 NOVEL EPIGENETIC BIOMARKERS MEDIATING BISPHENOL A EXPOSURE AND METABOLIC PHENOTYPES IN FEMALE MICE. THERE IS COMPELLING EVIDENCE THAT EPIGENETIC MODIFICATIONS LINK DEVELOPMENTAL ENVIRONMENTAL INSULTS TO ADULT DISEASE SUSCEPTIBILITY. ANIMAL STUDIES HAVE ASSOCIATED PERINATAL BISPHENOL A (BPA) EXPOSURE TO ALTERED DNA METHYLATION, BUT THESE STUDIES ARE OFTEN LIMITED TO CANDIDATE GENE AND GLOBAL NON-LOCI-SPECIFIC APPROACHES. BY USING AN EPIGENOME-WIDE DISCOVERY PLATFORM, WE ELUCIDATED EPIGENETIC ALTERATIONS IN LIVER TISSUE FROM ADULT MICE OFFSPRING (10 MONTHS) FOLLOWING PERINATAL BPA EXPOSURE AT HUMAN PHYSIOLOGICALLY RELEVANT DOSES (50-NG, 50-MUG, AND 50-MG BPA/KG DIET). BIOLOGICAL PATHWAY ANALYSIS IDENTIFIED AN ENRICHMENT OF SIGNIFICANT DIFFERENTIALLY METHYLATED REGIONS IN METABOLIC PATHWAYS AMONG FEMALES. FURTHERMORE, THROUGH THE USE OF TOP ENRICHED BIOLOGICAL PATHWAYS, 4 CANDIDATE GENES WERE CHOSEN TO ASSESS DNA METHYLATION AS A MEDIATING FACTOR LINKING THE ASSOCIATION OF PERINATAL BPA EXPOSURE TO METABOLIC PHENOTYPES PREVIOUSLY OBSERVED IN FEMALE OFFSPRING. DNA METHYLATION STATUS AT JANUS KINASE-2 (JAK-2), RETINOID X RECEPTOR (RXR), REGULATORY FACTOR X-ASSOCIATED PROTEIN (RFXAP), AND TRANSMEMBRANE PROTEIN 238 (TMEM238) WAS USED WITHIN A MEDIATIONAL REGRESSION ANALYSIS. DNA METHYLATION IN ALL FOUR OF THE CANDIDATE GENES WAS IDENTIFIED AS A MEDIATOR IN THE MECHANISTIC PATHWAY OF DEVELOPMENTAL BPA EXPOSURE AND FEMALE-SPECIFIC ENERGY EXPENDITURE, BODY WEIGHT, AND BODY FAT PHENOTYPES. DATA GENERATED FROM THIS STUDY ARE CRUCIAL FOR DECIPHERING THE MECHANISTIC ROLE OF EPIGENETICS IN THE PATHOGENESIS OF CHRONIC DISEASE AND THE DEVELOPMENT OF EPIGENETIC-BASED PREVENTION AND THERAPEUTIC STRATEGIES FOR COMPLEX HUMAN DISEASE. 2017 20 4019 35 LOW-DOSE OR LOW-DOSE-RATE IONIZING RADIATION-INDUCED BIOEFFECTS IN ANIMAL MODELS. ANIMAL EXPERIMENTAL STUDIES INDICATE THAT ACUTE OR CHRONIC LOW-DOSE IONIZING RADIATION (LDIR) (