1 2468 148 EPIGENETIC TOXICOLOGY AS TOXICANT-INDUCED CHANGES IN INTRACELLULAR SIGNALLING LEADING TO ALTERED GAP JUNCTIONAL INTERCELLULAR COMMUNICATION. COMMUNICATION MECHANISMS [EXTRA-, INTRA-, AND GAP JUNCTIONAL INTER-CELLULAR COMMUNICATION (GJIC)] CONTROL, FROM THE FERTILIZED EGG, THROUGH EMBRYOGENESIS TO MATURITY AND AGING, WHETHER A CELL PROLIFERATES, DIFFERENTIATES, DIES BY APOPTOSIS, OR IF DIFFERENTIATED, ADAPTIVELY RESPONDS TO ENDOGENOUS AND EXOGENOUS SIGNALS. FROM THE EGG TO THE 100 TRILLION CELLS IN THE HUMAN BODY, HEALTH IS MAINTAINED WHEN THESE COMMUNICATION PROCESSES BETWEEN STEM, PROGENITOR AND TERMINALLY DIFFERENTIATED CELLS ARE INTEGRATED. EACH CELL CHOICE INVOLVES 'EPIGENETIC' MECHANISMS TO ALTER THE EXPRESSION OF GENES AT THE TRANSCRIPTIONAL, TRANSLATIONAL OR POST-TRANSLATIONAL LEVELS. DISRUPTION OF THE COMMUNICATION MECHANISMS CAN BE EITHER ADAPTIVE OR MALADAPTIVE. MODULATION OF EXTRA-CELLULAR COMMUNICATION, EITHER BY GENETIC IMBALANCES OF GROWTH FACTORS, HORMONES OR NEUROTRANSMITTERS OR BY ENVIRONMENTAL, EXOGENOUS CHEMICALS CAN TRIGGER SIGNAL TRANSDUCING INTRA-CELLULAR MECHANISMS. THESE INTRA-CELLULAR SIGNALS CAN MODULATE GENE EXPRESSION AT THE TRANSCRIPTIONAL, TRANSLATIONAL OR POST-TRANSLATIONAL LEVELS WHILE ALSO MODULATING GJIC. UNTIMELY OR CHRONIC DISRUPTION OF GJIC DURING EMBRYONIC OR FETAL DEVELOPMENT COULD LEAD TO EMBRYONIC LETHALITY OR TERATOGENESIS. BY MODULATION OF GJIC, HOMEOSTATIC CONTROL OF CELL GROWTH, DIFFERENTIATION OR APOPTOSIS COULD LEAD TO SPECIFIC DISEASES, SUCH AS NEUROLOGICAL, CARDIOVASCULAR, REPRODUCTIVE OR ENDOCRINOLOGICAL DYSFUNCTION. CHEMICAL MODULATION OR ONCOGENE DOWN-REGULATION OF GJIC IN INITIATED TISSUES HAS BEEN SHOWN TO LEAD TO TUMOR PROMOTION. GENETIC SYNDROMES CARRYING A MUTATED GAP JUNCTION GENE, TOGETHER WITH SOME TRANSGENIC AND KNOCK-OUT GAP JUNCTION GENE MICE, PROVIDE EVIDENCE FOR THE IMPORTANCE OF THIS ORGANELLE FOUND ONLY IN METAZOANS. IMPLICATIONS FOR 'THRESHOLDS' TO TOXICANTS AND FOR RISK ASSESSMENT ARE EVIDENT. 1998 2 312 29 ALCOHOL FEEDING IN MICE PROMOTES COLONIC HYPERPERMEABILITY AND CHANGES IN COLONIC ORGANOID STEM CELL FATE. BACKGROUND: ALCOHOL INCREASES INTESTINAL PERMEABILITY TO PROINFLAMMATORY MICROBIAL PRODUCTS THAT PROMOTE LIVER DISEASE, EVEN AFTER A PERIOD OF SOBRIETY. WE SOUGHT TO TEST THE HYPOTHESIS THAT ALCOHOL AFFECTS INTESTINAL STEM CELLS USING AN IN VIVO MODEL AND EX VIVO ORGANOIDS GENERATED FROM JEJUNUM AND COLON FROM MICE FED CHRONIC ALCOHOL. METHODS: MICE WERE FED A CONTROL OR AN ALCOHOL DIET. INTESTINAL PERMEABILITY, LIVER STEATOSIS-INFLAMMATION, AND STOOL SHORT-CHAIN FATTY ACIDS (SCFAS) WERE MEASURED. JEJUNUM AND COLONIC ORGANOIDS AND TISSUE WERE STAINED FOR STEM CELL, CELL LINEAGE, AND APICAL JUNCTION MARKERS WITH ASSESSMENT OF MRNA BY PCR AND RNA-SEQ. CHIP-PCR ANALYSIS WAS CARRIED OUT FOR NOTCH1 USING AN ANTIBODY SPECIFIC FOR ACETYLATED HISTONE 3. RESULTS: ALCOHOL-FED MICE EXHIBITED COLONIC (BUT NOT SMALL INTESTINAL) HYPERPERMEABILITY, STEATOHEPATITIS, AND DECREASED BUTYRATE/TOTAL SCFA RATIO IN STOOL. STEM CELL, CELL LINEAGE, AND APICAL JUNCTION MARKER STAINING IN TISSUE OR ORGANOIDS FROM JEJUNUM TISSUE WERE NOT IMPACTED BY ALCOHOL. ONLY CHROMOGRANIN A (CHGA) WAS INCREASED IN JEJUNUM ORGANOIDS BY QPCR. HOWEVER, COLONIC TISSUE AND ORGANOID STAINING EXHIBITED AN ALCOHOL-INDUCED SIGNIFICANT DECREASE IN CYTOKERATIN 20+ (KRT20+) ABSORPTIVE LINEAGE ENTEROCYTES, A DECREASE IN OCCLUDIN AND E-CADHERIN APICAL JUNCTION PROTEINS, AN INCREASE IN CHGA, AND AN INCREASE IN THE LGR5 STEM CELL MARKER. QPCR REVEALED AN ALCOHOL-INDUCED DECREASE IN COLONIC ORGANOID AND TISSUE NOTCH1, HES1, AND KRT20 AND INCREASED CHGA, SUPPORTING AN ALTERATION IN STEM CELL FATE DUE TO DECREASED NOTCH1 EXPRESSION. COLONIC TISSUE CHIP-PCR REVEALED ALCOHOL FEEDING SUPPRESSED NOTCH1 MRNA EXPRESSION (VIA DEACETYLATION OF HISTONE H3) AND DECREASED NOTCH1 TISSUE STAINING. CONCLUSIONS: DATA SUPPORT A MODEL FOR ALCOHOL-INDUCED COLONIC HYPERPERMEABILITY VIA EPIGENETIC EFFECTS ON NOTCH1, AND THUS HES1, SUPPRESSION THROUGH A MECHANISM INVOLVING HISTONE H3 DEACETYLATION AT THE NOTCH1 LOCUS. THIS DECREASED ENTEROCYTE AND INCREASED ENTEROENDOCRINE CELL COLONIC STEM CELL FATE AND DECREASED APICAL JUNCTIONAL PROTEINS LEADING TO HYPERPERMEABILITY. 2017 3 4338 28 MICROVASCULAR BARRIER PROTECTION BY MICRORNA-183 VIA FOXO1 REPRESSION: A PATHWAY DISTURBED IN NEUROPATHY AND COMPLEX REGIONAL PAIN SYNDROME. BLOOD NERVE BARRIER DISRUPTION AND EDEMA ARE COMMON IN NEUROPATHIC PAIN AS WELL AS IN COMPLEX REGIONAL PAIN SYNDROME (CRPS). MICRORNAS (MIRNA) ARE EPIGENETIC MULTITARGET SWITCHES CONTROLLING NEURONAL AND NON-NEURONAL CELLS IN PAIN. THE MIR-183 COMPLEX ATTENUATES HYPEREXCITABILITY IN NOCICEPTORS, BUT ADDITIONAL NON-NEURONAL EFFECTS VIA TRANSCRIPTION FACTORS COULD CONTRIBUTE AS WELL. THIS STUDY EXPLORED EXOSOMAL MIR-183 IN CRPS AND MURINE NEUROPATHY, ITS EFFECT ON THE MICROVASCULAR BARRIER VIA TRANSCRIPTION FACTOR FOXO1 AND TIGHT JUNCTION PROTEIN CLAUDIN-5, AND ITS ANTIHYPERALGESIC POTENTIAL. SCIATIC MIR-183 DECREASED AFTER CCI. SUBSTITUTION WITH PERINEURAL MIR-183 MIMIC ATTENUATED MECHANICAL HYPERSENSITIVITY AND RESTORED BLOOD NERVE BARRIER FUNCTION. IN VITRO, SERUM FROM CCI MICE UND CRPS PATIENTS WEAKENED THE MICROVASCULAR BARRIER OF MURINE CEREBELLAR ENDOTHELIAL CELLS, INCREASED ACTIVE FOXO1 AND REDUCED CLAUDIN-5, CONCOMITANT WITH A LACK OF EXOSOMAL MIR-183 IN CRPS PATIENTS. CELLULAR STRESS ALSO COMPROMISED THE MICROVASCULAR BARRIER WHICH WAS RESCUED EITHER BY MIR-183 MIMIC VIA FOXO1 REPRESSION OR BY PRIOR SILENCING OF FOXO1. PERSPECTIVE: LOW MIR-183 LEADING TO BARRIER IMPAIRMENT VIA FOXO1 AND SUBSEQUENT CLAUDIN-5 SUPPRESSION IS A NEW ASPECT IN THE PATHOPHYSIOLOGY OF CRPS AND NEUROPATHIC PAIN. THIS PATHWAY MIGHT HELP UNTANGLE THE WIDE SYMPTOMATIC RANGE OF CRPS AND NURTURE FURTHER RESEARCH INTO MIRNA MIMICS OR FOXO1 INHIBITORS. 2022 4 4337 30 MICROTUBULES AS MAJOR REGULATORS OF ENDOTHELIAL FUNCTION: IMPLICATION FOR LUNG INJURY. ENDOTHELIAL DYSFUNCTION HAS BEEN ATTRIBUTED AS ONE OF THE MAJOR COMPLICATIONS IN COVID-19 PATIENTS, A GLOBAL PANDEMIC THAT HAS ALREADY CAUSED OVER 4 MILLION DEATHS WORLDWIDE. THE DYSFUNCTION OF ENDOTHELIAL BARRIER IS CHARACTERIZED BY AN INCREASE IN ENDOTHELIAL PERMEABILITY AND INFLAMMATORY RESPONSES, AND HAS EVEN BROADER IMPLICATIONS IN THE PATHOGENESIS OF ACUTE RESPIRATORY SYNDROMES SUCH AS ARDS, SEPSIS AND CHRONIC ILLNESSES REPRESENTED BY PULMONARY ARTERIAL HYPERTENSION AND INTERSTITIAL LUNG DISEASE. THE STRUCTURAL INTEGRITY OF ENDOTHELIAL BARRIER IS MAINTAINED BY CYTOSKELETON ELEMENTS, CELL-SUBSTRATE FOCAL ADHESION AND ADHESIVE CELL JUNCTIONS. AGONIST-MEDIATED CHANGES IN ENDOTHELIAL PERMEABILITY ARE DIRECTLY ASSOCIATED WITH REORGANIZATION OF ACTOMYOSIN CYTOSKELETON LEADING TO CELL CONTRACTION AND OPENING OF INTERCELLULAR GAPS OR ENHANCEMENT OF CORTICAL ACTIN CYTOSKELETON ASSOCIATED WITH STRENGTHENING OF ENDOTHELIAL BARRIER. THE ROLE OF ACTIN CYTOSKELETON REMODELING IN ENDOTHELIAL BARRIER REGULATION HAS TAKEN THE CENTRAL STAGE, BUT THE IMPACT OF MICROTUBULES IN THIS PROCESS REMAINS LESS EXPLORED AND UNDER-APPRECIATED. THIS REVIEW WILL SUMMARIZE THE CURRENT KNOWLEDGE ON THE CROSSTALK BETWEEN MICROTUBULES DYNAMICS AND ACTIN CYTOSKELETON REMODELING, DESCRIBE THE SIGNALING MECHANISMS MEDIATING THIS CROSSTALK, DISCUSS EPIGENETIC REGULATION OF MICROTUBULES STABILITY AND ITS NEXUS WITH ENDOTHELIAL BARRIER MAINTENANCE, AND OVERVIEW A ROLE OF MICROTUBULES IN TARGETED DELIVERY OF SIGNALING MOLECULES REGULATING ENDOTHELIAL PERMEABILITY AND INFLAMMATION. 2021 5 3864 33 JAK-STAT PATHWAY INHIBITION PARTIALLY RESTORES INTESTINAL HOMEOSTASIS IN HDAC1- AND HDAC2-INTESTINAL EPITHELIAL CELL-DEFICIENT MICE. WE HAVE PREVIOUSLY REPORTED THAT HISTONE DEACETYLASE EPIGENETIC REGULATOR HDAC1 AND HDAC2 DELETION IN INTESTINAL EPITHELIAL CELLS (IEC) DISRUPTS MUCOSAL TISSUE ARCHITECTURE AND BARRIER, CAUSING CHRONIC INFLAMMATION. IN THIS STUDY, PROTEOME AND TRANSCRIPTOME ANALYSIS REVEALED THE IMPORTANCE OF SIGNALING PATHWAYS INDUCED UPON GENETIC IEC-HDAC1 AND HDAC2 DELETION. INDEED, GENE ONTOLOGY BIOLOGICAL PROCESS ANALYSIS OF ENRICHED DEFICIENT IEC RNA AND PROTEINS IDENTIFIED COMMON PATHWAYS, INCLUDING LIPID METABOLIC AND OXIDATION-REDUCTION PROCESS, CELL ADHESION, AND ANTIGEN PROCESSING AND PRESENTATION, RELATED TO IMMUNE RESPONSES, CORRELATING WITH DYSREGULATION OF MAJOR HISTOCOMPATIBILITY COMPLEX (MHC) CLASS II GENES. TOP UPSTREAM REGULATORS INCLUDED REGULATORS ASSOCIATED WITH ENVIRONMENTAL SENSING PATHWAYS TO XENOBIOTICS, MICROBIAL AND DIET-DERIVED LIGANDS, AND ENDOGENOUS METABOLITES. PROTEOME ANALYSIS REVEALED MTOR SIGNALING IEC-SPECIFIC DEFECTS. IN ADDITION TO MTOR, THE STAT AND NOTCH PATHWAYS WERE DYSREGULATED SPECIFICALLY IN JEJUNAL IEC. TO DETERMINE THE IMPACT OF PATHWAY DYSREGULATION ON MUTANT JEJUNUM ALTERATIONS, WE TREATED MUTANT MICE WITH TOFACITINIB, A JAK INHIBITOR. TREATMENT WITH THE INHIBITOR PARTIALLY CORRECTED PROLIFERATION AND TIGHT JUNCTION DEFECTS, AS WELL AS NICHE STABILIZATION BY INCREASING PANETH CELL NUMBERS. THUS, IEC-SPECIFIC HISTONE DEACETYLASES 1 (HDAC1) AND 2 (HDAC2) SUPPORT INTESTINAL HOMEOSTASIS BY REGULATING SURVIVAL AND TRANSLATION PROCESSES, AS WELL AS DIFFERENTIATION AND METABOLIC PATHWAYS. HDAC1 AND HDAC2 MAY PLAY AN IMPORTANT ROLE IN THE REGULATION OF IEC-SPECIFIC INFLAMMATORY RESPONSES BY CONTROLLING, DIRECTLY OR INDIRECTLY, THE JAK/STAT PATHWAY. IEC-SPECIFIC JAK/STAT PATHWAY DEREGULATION MAY BE, AT LEAST IN PART, RESPONSIBLE FOR INTESTINAL HOMEOSTASIS DISRUPTION IN MUTANT MICE. 2021 6 351 28 ALTERED ENDOTHELIAL DYSFUNCTION-RELATED MIRS IN PLASMA FROM ME/CFS PATIENTS. MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A COMPLEX DISEASE CHARACTERIZED BY UNEXPLAINED DEBILITATING FATIGUE. ALTHOUGH THE ETIOLOGY IS UNKNOWN, EVIDENCE SUPPORTS IMMUNOLOGICAL ABNORMALITIES, SUCH AS PERSISTENT INFLAMMATION AND IMMUNE-CELL ACTIVATION, IN A SUBSET OF PATIENTS. SINCE THE INTERPLAY BETWEEN INFLAMMATION AND VASCULAR ALTERATIONS IS WELL-ESTABLISHED IN OTHER DISEASES, ENDOTHELIAL DYSFUNCTION HAS EMERGED AS ANOTHER PLAYER IN ME/CFS PATHOGENESIS. ENDOTHELIAL NITRIC OXIDE SYNTHASE (ENOS) GENERATES NITRIC OXIDE (NO) THAT MAINTAINS ENDOTHELIAL HOMEOSTASIS. ENOS IS ACTIVATED BY SILENT INFORMATION REGULATOR 1 (SIRT1), AN ANTI-INFLAMMATORY PROTEIN. DESPITE ITS RELEVANCE, NO STUDY HAS ADDRESSED THE SIRT1/ENOS AXIS IN ME/CFS. THE INTEREST IN CIRCULATING MICRORNAS (MIRS) AS POTENTIAL BIOMARKERS IN ME/CFS HAS INCREASED IN RECENT YEARS. ACCORDINGLY, WE ANALYZE A SET OF MIRS REPORTED TO MODULATE THE SIRT1/ENOS AXIS USING PLASMA FROM ME/CFS PATIENTS. OUR RESULTS SHOW THAT MIR-21, MIR-34A, MIR-92A, MIR-126, AND MIR-200C ARE JOINTLY INCREASED IN ME/CFS PATIENTS COMPARED TO HEALTHY CONTROLS. A SIMILAR FINDING WAS OBTAINED WHEN ANALYZING PUBLIC MIR DATA ON PERIPHERAL BLOOD MONONUCLEAR CELLS. BIOINFORMATICS ANALYSIS SHOWS THAT ENDOTHELIAL FUNCTION-RELATED SIGNALING PATHWAYS ARE ASSOCIATED WITH THESE MIRS, INCLUDING OXIDATIVE STRESS AND OXYGEN REGULATION. INTERESTINGLY, HISTONE DEACETYLASE 1, A PROTEIN RESPONSIBLE FOR EPIGENETIC REGULATIONS, REPRESENTED THE MOST RELEVANT NODE WITHIN THE NETWORK. IN CONCLUSION, OUR STUDY PROVIDES A BASIS TO FIND ENDOTHELIAL DYSFUNCTION-RELATED BIOMARKERS AND EXPLORE NOVEL TARGETS IN ME/CFS. 2021 7 1501 21 DNA METHYLATION ANALYSIS OF HUMAN TISSUE-SPECIFIC CONNEXIN GENES. CONNEXINS ARE THE STRUCTURAL PROTEINS OF GAP JUNCTIONS AND THEIR FUNCTIONING AS TUMOR SUPPRESSORS IS WELL KNOWN. EPIGENETIC MODIFICATIONS, SUCH AS METHYLATION OF CONNEXIN GENES, PLAY IMPORTANT ROLES IN REGULATING GENE EXPRESSION. OVER THE PAST DECADE, SEVERAL METHODS HAVE BEEN APPLIED TO CHARACTERIZE DNA METHYLATION-SPECIFIC LOCI OF CONNEXIN GENES. THIS CHAPTER DESCRIBES ANALYSIS OF SELECTIVE CONNEXIN32 AND CONNEXIN43 GENE DNA METHYLATION IN HUMAN GASTRIC TISSUES USING METHYLATION-SPECIFIC PCR, BISULFITE-SPECIFIC PCR SEQUENCING AS WELL AS MASSARRAY TECHNIQUES. 2016 8 4470 42 MOLECULAR NEUROPATHOLOGY OF ASTROCYTES AND OLIGODENDROCYTES IN ALCOHOL USE DISORDERS. POSTMORTEM STUDIES REVEAL STRUCTURAL AND MOLECULAR ALTERATIONS OF ASTROCYTES AND OLIGODENDROCYTES IN BOTH THE GRAY AND WHITE MATTER (GM AND WM) OF THE PREFRONTAL CORTEX (PFC) IN HUMAN SUBJECTS WITH CHRONIC ALCOHOL ABUSE OR DEPENDENCE. THESE GLIAL CELLULAR CHANGES APPEAR TO PARALLEL AND MAY LARGELY EXPLAIN STRUCTURAL AND FUNCTIONAL ALTERATIONS DETECTED USING NEUROIMAGING TECHNIQUES IN SUBJECTS WITH ALCOHOL USE DISORDERS (AUDS). MOREOVER, DUE TO THE CRUCIAL ROLES OF ASTROCYTES AND OLIGODENDROCYTES IN NEUROTRANSMISSION AND SIGNAL CONDUCTION, THESE CELLS ARE VERY LIKELY MAJOR PLAYERS IN THE MOLECULAR MECHANISMS UNDERPINNING ALCOHOLISM-RELATED CONNECTIVITY DISTURBANCES BETWEEN THE PFC AND RELEVANT INTERCONNECTING BRAIN REGIONS. THE GLIA-MEDIATED ETIOLOGY OF ALCOHOL-RELATED BRAIN DAMAGE IS LIKELY MULTIFACTORIAL SINCE METABOLIC, HORMONAL, HEPATIC AND HEMODYNAMIC FACTORS AS WELL AS DIRECT ACTIONS OF ETHANOL OR ITS METABOLITES HAVE THE POTENTIAL TO DISRUPT DISTINCT ASPECTS OF GLIAL NEUROBIOLOGY. STUDIES IN ANIMAL MODELS OF ALCOHOLISM AND POSTMORTEM HUMAN BRAINS HAVE IDENTIFIED ASTROCYTE MARKERS ALTERED IN RESPONSE TO SIGNIFICANT EXPOSURES TO ETHANOL OR DURING ALCOHOL WITHDRAWAL, SUCH AS GAP-JUNCTION PROTEINS, GLUTAMATE TRANSPORTERS OR ENZYMES RELATED TO GLUTAMATE AND GAMMA-AMINOBUTYRIC ACID (GABA) METABOLISM. CHANGES IN THESE PROTEINS AND THEIR REGULATORY PATHWAYS WOULD NOT ONLY CAUSE GM NEURONAL DYSFUNCTION, BUT ALSO DISTURBANCES IN THE ABILITY OF WM AXONS TO CONVEY IMPULSES. IN ADDITION, ALCOHOLISM ALTERS THE EXPRESSION OF ASTROCYTE AND MYELIN PROTEINS AND OF OLIGODENDROCYTE TRANSCRIPTION FACTORS IMPORTANT FOR THE MAINTENANCE AND PLASTICITY OF MYELIN SHEATHS IN WM AND GM. THESE CHANGES ARE CONCOMITANT WITH EPIGENETIC DNA AND HISTONE MODIFICATIONS AS WELL AS ALTERATIONS IN REGULATORY MICRORNAS (MIRNAS) THAT LIKELY CAUSE PROFOUND DISTURBANCES OF GENE EXPRESSION AND PROTEIN TRANSLATION. KNOWLEDGE IS ALSO AVAILABLE ABOUT INTERACTIONS BETWEEN ASTROCYTES AND OLIGODENDROCYTES NOT ONLY AT THE NODES OF RANVIER (NR), BUT ALSO IN GAP JUNCTION-BASED ASTROCYTE-OLIGODENDROCYTE CONTACTS AND OTHER FORMS OF CELL-TO-CELL COMMUNICATION NOW UNDERSTOOD TO BE CRITICAL FOR THE MAINTENANCE AND FORMATION OF MYELIN. CLOSE INTERACTIONS BETWEEN ASTROCYTES AND OLIGODENDROCYTES ALSO SUGGEST THAT THERAPIES FOR ALCOHOLISM BASED ON A SPECIFIC GLIAL CELL TYPE PATHOLOGY WILL REQUIRE A BETTER UNDERSTANDING OF MOLECULAR INTERACTIONS BETWEEN DIFFERENT CELL TYPES, AS WELL AS CONSIDERING THE POSSIBILITY OF USING COMBINED MOLECULAR APPROACHES FOR MORE EFFECTIVE THERAPIES. 2018 9 2702 26 EXCITOTOXICITY AND OVERNUTRITION ADDITIVELY IMPAIR METABOLIC FUNCTION AND IDENTITY OF PANCREATIC BETA-CELLS. A SUSTAINED INCREASE IN INTRACELLULAR CA(2+) CONCENTRATION (REFERRED TO HEREAFTER AS EXCITOTOXICITY), BROUGHT ON BY CHRONIC METABOLIC STRESS, MAY CONTRIBUTE TO PANCREATIC BETA-CELL FAILURE. TO DETERMINE THE ADDITIVE EFFECTS OF EXCITOTOXICITY AND OVERNUTRITION ON BETA-CELL FUNCTION AND GENE EXPRESSION, WE ANALYZED THE IMPACT OF A HIGH-FAT DIET (HFD) ON ABCC8 KNOCKOUT MICE. EXCITOTOXICITY CAUSED BETA-CELLS TO BE MORE SUSCEPTIBLE TO HFD-INDUCED IMPAIRMENT OF GLUCOSE HOMEOSTASIS, AND THESE EFFECTS WERE MITIGATED BY VERAPAMIL, A CA(2+) CHANNEL BLOCKER. EXCITOTOXICITY, OVERNUTRITION, AND THE COMBINATION OF BOTH STRESSES CAUSED SIMILAR BUT DISTINCT ALTERATIONS IN THE BETA-CELL TRANSCRIPTOME, INCLUDING ADDITIVE INCREASES IN GENES ASSOCIATED WITH MITOCHONDRIAL ENERGY METABOLISM, FATTY ACID BETA-OXIDATION, AND MITOCHONDRIAL BIOGENESIS AND THEIR KEY REGULATOR PPARGC1A OVERNUTRITION WORSENED EXCITOTOXICITY-INDUCED MITOCHONDRIAL DYSFUNCTION, INCREASING METABOLIC INFLEXIBILITY AND MITOCHONDRIAL DAMAGE. IN ADDITION, EXCITOTOXICITY AND OVERNUTRITION, INDIVIDUALLY AND TOGETHER, IMPAIRED BOTH BETA-CELL FUNCTION AND IDENTITY BY REDUCING EXPRESSION OF GENES IMPORTANT FOR INSULIN SECRETION, CELL POLARITY, CELL JUNCTION, CILIA, CYTOSKELETON, VESICULAR TRAFFICKING, AND REGULATION OF BETA-CELL EPIGENETIC AND TRANSCRIPTIONAL PROGRAM. SEX HAD AN IMPACT ON ALL BETA-CELL RESPONSES, WITH MALE ANIMALS EXHIBITING GREATER METABOLIC STRESS-INDUCED IMPAIRMENTS THAN FEMALES. TOGETHER, THESE FINDINGS INDICATE THAT A SUSTAINED INCREASE IN INTRACELLULAR CA(2+), BY ALTERING MITOCHONDRIAL FUNCTION AND IMPAIRING BETA-CELL IDENTITY, AUGMENTS OVERNUTRITION-INDUCED BETA-CELL FAILURE. 2020 10 6038 37 THE CHEMICAL DEFENSIVE SYSTEM IN THE PATHOBIOLOGY OF IDIOPATHIC ENVIRONMENT-ASSOCIATED DISEASES. CHEMICAL DEFENSIVE SYSTEM CONSISTING OF BIO-SENSORING, TRANSMITTING, AND RESPONSIVE ELEMENTS HAS BEEN EVOLVED TO PROTECT MULTI-CELLULAR ORGANISMS AGAINST ENVIRONMENTAL CHEMICAL INSULTS (XENOBIOTICS) AND TO MAINTAIN HOMEOSTASIS OF ENDOGENOUS LOW MOLECULAR WEIGHT METABOLITES (ENDOBIOTICS). BOTH GENETIC AND EPIGENETIC DEFECTS OF THE SYSTEM IN ASSOCIATION WITH CARCINOGENESIS AND INDIVIDUAL SENSITIVITY TO ANTI-TUMOR THERAPIES HAVE BEEN INTENSELY STUDIED. RECENTLY, SEVERAL NON-TUMOR HUMAN PATHOLOGIES WITH EVIDENT ENVIRONMENTAL COMPONENTS SUCH AS RATHER RARE FUNCTIONAL SYNDROMES (MULTIPLE CHEMICAL SENSITIVITY, CHRONIC FATIGUE, PERSIAN GULF, AND FIBROMYALGIA NOW COLLECTIVELY LABELED AS IDIOPATHIC ENVIRONMENTAL INTOLERANCES) AND COMMON DISEASES (VITILIGO AND SYSTEMIC LUPUS ERYTHEMATOSUS) HAVE BECOME SUBJECTS OF THE RESEARCH ON THE IMPAIRED METABOLISM AND DETOXIFICATION OF XENOBIOTICS AND ENDOGENOUS TOXINS. HERE, WE COLLECTED AND CRITICALLY REVIEWED EPIDEMIOLOGICAL, GENETIC, AND BIOCHEMICAL DATA ON THE INVOLVEMENT AND POSSIBLE ROLE OF CYTOCHROME P450 SUPER FAMILY ENZYMES, GLUTATHIONE-S-TRANSFERASE ISOZYMES, CATECHOL-O-METHYL-TRANSFERASE, UDP-GLUCURONOSYL TRANSFERASES, AND PROTEINS DETOXIFYING INORGANIC AND ORGANIC PEROXIDES (CATALASE, GLUTATHIONE PEROXIDASE, AND PEROXIREDOXIN) IN THE ABOVE PATHOLOGIES. GENETIC PREDISPOSITION ASSESSED MAINLY BY SINGLE NUCLEOTIDE POLYMORPHISM AND GENE EXPRESSION ANALYSES REVEALED CORRELATIONS BETWEEN DEFECTS IN GENES ENCODING XENOBIOTIC-METABOLIZING AND/OR DETOXIFYING ENZYMES AND RISK/SEVERITY OF THESE SYNDROMES/DISEASES. PROTEOME ANALYSIS IDENTIFIED ABNORMAL EXPRESSION OF THE ENZYMES. THEIR FUNCTIONS WERE AFFECTED EPIGENETICALLY LEADING TO METABOLIC IMPAIRMENT AND, AS A CONSEQUENCE, TO THE NEGATIVE HEALTH OUTCOMES SHARED BY SOME OF THESE PATHOLOGIES. DATA OBTAINED SO FAR SUGGEST THAT DISTINCT COMPONENTS OF THE CHEMICAL DEFENSIVE SYSTEM COULD BE SUITABLE MOLECULAR TARGETS FOR FUTURE PATHOGENIC THERAPIES. 2009 11 4116 33 MECHANISMS OF AIRWAY EPITHELIAL INJURY AND ABNORMAL REPAIR IN ASTHMA AND COPD. THE AIRWAY EPITHELIUM COMPRISES OF DIFFERENT CELL TYPES AND ACTS AS A PHYSICAL BARRIER PREVENTING PATHOGENS, INCLUDING INHALED PARTICLES AND MICROBES, FROM ENTERING THE LUNGS. GOBLET CELLS AND SUBMUCOSAL GLANDS PRODUCE MUCUS THAT TRAPS PATHOGENS, WHICH ARE EXPELLED FROM THE RESPIRATORY TRACT BY CILIATED CELLS. BASAL CELLS ACT AS PROGENITOR CELLS, DIFFERENTIATING INTO DIFFERENT EPITHELIAL CELL TYPES, TO MAINTAIN HOMEOSTASIS FOLLOWING INJURY. ADHERENS AND TIGHT JUNCTIONS BETWEEN CELLS MAINTAIN THE EPITHELIAL BARRIER FUNCTION AND REGULATE THE MOVEMENT OF MOLECULES ACROSS IT. IN THIS REVIEW WE DISCUSS HOW ABNORMAL EPITHELIAL STRUCTURE AND FUNCTION, CAUSED BY CHRONIC INJURY AND ABNORMAL REPAIR, DRIVES AIRWAY DISEASE AND SPECIFICALLY ASTHMA AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD). IN BOTH DISEASES, INHALED ALLERGENS, POLLUTANTS AND MICROBES DISRUPT JUNCTIONAL COMPLEXES AND PROMOTE CELL DEATH, IMPAIRING THE BARRIER FUNCTION AND LEADING TO INCREASED PENETRATION OF PATHOGENS AND A CONSTANT AIRWAY IMMUNE RESPONSE. IN ASTHMA, THE INFLAMMATORY RESPONSE PRECIPITATES THE EPITHELIAL INJURY AND DRIVES ABNORMAL BASAL CELL DIFFERENTIATION. THIS LEADS TO REDUCED CILIATED CELLS, GOBLET CELL HYPERPLASIA AND INCREASED EPITHELIAL MESENCHYMAL TRANSITION, WHICH CONTRIBUTE TO IMPAIRED MUCOCILIARY CLEARANCE AND AIRWAY REMODELLING. IN COPD, CHRONIC OXIDATIVE STRESS AND INFLAMMATION TRIGGER PREMATURE EPITHELIAL CELL SENESCENCE, WHICH CONTRIBUTES TO LOSS OF EPITHELIAL INTEGRITY AND AIRWAY INFLAMMATION AND REMODELLING. INCREASED NUMBERS OF BASAL CELLS SHOWING DEREGULATED DIFFERENTIATION, CONTRIBUTES TO CILIARY DYSFUNCTION AND MUCOUS HYPERPRODUCTION IN COPD AIRWAYS. DEFECTIVE ANTIOXIDANT, ANTIVIRAL AND DAMAGE REPAIR MECHANISMS, POSSIBLY DUE TO GENETIC OR EPIGENETIC FACTORS, MAY CONFER SUSCEPTIBILITY TO AIRWAY EPITHELIAL DYSFUNCTION IN THESE DISEASES. THE CURRENT EVIDENCE SUGGESTS THAT A CONSTANT CYCLE OF INJURY AND ABNORMAL REPAIR OF THE EPITHELIUM DRIVES CHRONIC AIRWAY INFLAMMATION AND REMODELLING IN ASTHMA AND COPD. MECHANISTIC UNDERSTANDING OF INJURY SUSCEPTIBILITY AND DAMAGE RESPONSE MAY LEAD TO IMPROVED THERAPIES FOR THESE DISEASES. 2023 12 3884 46 KIDNEY DISEASE IN DIABETES. PERSONS WITH DIABETES MAKE UP THE FASTEST GROWING GROUP OF KIDNEY DIALYSIS AND TRANSPLANT RECIPIENTS IN THE UNITED STATES. IN 1985, WHEN THE FIRST EDITION OF DIABETES IN AMERICA WAS PUBLISHED, 20,961 PERSONS WITH DIABETES WERE RECEIVING RENAL REPLACEMENT THERAPY, REPRESENTING 29% OF ALL NEW CASES OF END-STAGE RENAL DISEASE (ESRD). BY 2012, 239,837 PERSONS WITH DIABETES WERE ON RENAL REPLACEMENT THERAPY, ACCOUNTING FOR 44% OF ALL NEW ESRD CASES. THE INCREASED COUNT REFLECTS GROWTH IN DIABETES PREVALENCE AND INCREASED ACCESS TO DIALYSIS AND TRANSPLANTATION. THOSE WITH A PRIMARY DIAGNOSIS OF DIABETES HAVE LOWER SURVIVAL RELATIVE TO OTHER CAUSES OF ESRD, PRIMARILY BECAUSE OF THE COEXISTENT MORBIDITY ASSOCIATED WITH DIABETES, PARTICULARLY CARDIOVASCULAR DISEASES (CVD). WHILE SURVIVAL ON DIALYSIS HAS SLOWLY IMPROVED ACROSS MODALITIES SINCE THE 1990S, IT REMAINS REDUCED IN PERSONS WITH DIABETES, HALF OF WHOM DIE WITHIN 3 YEARS OF BEGINNING DIALYSIS IN THE UNITED STATES. SIMILAR TO PERSONS WITH ESRD IN GENERAL, THE LEADING CAUSES OF DEATH AMONG ADULTS WITH DIABETES WHO STARTED DIALYSIS IN 1995-2009 WERE CVD (58% OF THE DEATHS) AND INFECTIONS (13% OF THE DEATHS). KIDNEY TRANSPLANT RECIPIENTS WITH DIABETES HAVE MUCH BETTER SURVIVAL THAN THOSE ON DIALYSIS, INDICATING A SIGNIFICANT IMPACT OF THE TYPE OF RENAL REPLACEMENT THERAPY (TRANSPLANT VERSUS DIALYSIS) ON LONG-TERM SURVIVAL. KIDNEY FAILURE AFFECTS ABOUT 1% OF PERSONS WITH DIABETES IN THE UNITED STATES. A CONSIDERABLY HIGHER PROPORTION, ABOUT 40%, HAVE LESS SEVERE KIDNEY DISEASE. SINCE THE SECOND EDITION OF DIABETES IN AMERICA WAS PUBLISHED IN 1995, A WEALTH OF NEW INFORMATION HAS CONTRIBUTED SUBSTANTIALLY TO THE UNDERSTANDING OF KIDNEY DISEASE ASSOCIATED WITH DIABETES. IN 2002, THE NATIONAL KIDNEY FOUNDATION'S KIDNEY DISEASE OUTCOME QUALITY INITIATIVE PUBLISHED A UNIFORM DEFINITION OF CHRONIC KIDNEY DISEASE (CKD) AND CLASSIFICATION OF ITS STAGES IRRESPECTIVE OF UNDERLYING CAUSE, THUS PROVIDING A COMMON LANGUAGE FOR DEFINING BOTH THE SEVERITY AND PROGNOSIS OF KIDNEY DISEASE. THE DEFINITION AND CLASSIFICATION OF CKD WERE SUBSEQUENTLY UPDATED AND REFINED BY THE KIDNEY DISEASE: IMPROVING GLOBAL OUTCOMES IN 2012. ACCORDINGLY, CKD IS CLASSIFIED BASED ON BOTH ALBUMINURIA AND GLOMERULAR FILTRATION RATE (GFR) CATEGORIES, AND TOGETHER WITH KIDNEY FAILURE, THESE CONDITIONS ARE COLLECTIVELY REFERRED TO AS CKD, REGARDLESS OF ETIOLOGY. IN ADDITION, THE KIDNEY DISEASE: IMPROVING GLOBAL OUTCOMES RECOMMENDS USING EQUATIONS TO ESTIMATE GFR (EGFR), WHICH INCLUDE THE ROUTINELY OBTAINED VARIABLES SERUM CREATININE, AGE, SEX, AND RACE/ETHNICITY. THE USE OF SERUM CYSTATIN C, AN ENDOGENOUS FILTRATION MARKER LESS INFLUENCED THAN SERUM CREATININE BY VARIATIONS IN MUSCLE MASS, DIET, AND TUBULAR SECRETION, HAS EMERGED AS AN ALTERNATIVE OR AN ADJUNCT TO SERUM CREATININE-BASED EQUATIONS, PARTICULARLY IN PERSONS WITH DIABETES, IN WHOM EARLY KIDNEY DISEASE IS OFTEN CHARACTERIZED BY ELEVATED GFR. SINCE THE LATE 1990S, NEW MOLECULAR MECHANISMS HAVE BEEN DEFINED THAT ARE HELPING TO EXPLAIN THE DEVELOPMENT AND PROGRESSION OF DIABETIC KIDNEY DISEASE. GLOMERULAR STRUCTURAL LESIONS WERE FOUND TO EXPLAIN 95% OF THE VARIABILITY IN ALBUMIN EXCRETION AND 78% OF GFR VARIABILITY. THE LATTER PERCENTAGE INCREASED TO 92% BY ADDING INDICES OF GLOMERULAR-TUBULAR JUNCTION ABNORMALITIES AND INTERSTITIAL EXPANSION TO THE REGRESSION MODELS. PODOCYTE INJURY APPEARS TO PLAY AN ESSENTIAL ROLE IN THE PROGRESSION OF DIABETIC NEPHROPATHY. IN PERSONS WITH EITHER TYPE 1 OR TYPE 2 DIABETES, PODOCYTE CHANGES MAY OCCUR EVEN BEFORE THE INCREASE IN ALBUMINURIA, SUGGESTING THAT DIABETES ITSELF MAY INDUCE PODOCYTE ALTERATIONS. MUCH HAS ALSO BEEN WRITTEN ABOUT THE PROGNOSTIC IMPLICATIONS OF CKD. ELEVATED ALBUMINURIA AND LOW GFR ARE ASSOCIATED WITH ESRD, FATAL AND NONFATAL CVD, AND ALL-CAUSE MORTALITY. A META-ANALYSIS OF 1,024,977 PARTICIPANTS (NEARLY 13% WITH DIABETES) FROM 30 GENERAL POPULATION AND HIGH-RISK CARDIOVASCULAR COHORTS AND 13 CKD COHORTS INDICATED THAT WHILE THE ABSOLUTE RISKS FOR ALL-CAUSE AND CVD MORTALITY ARE HIGHER IN THE PRESENCE OF DIABETES, THE RELATIVE RISKS OF ESRD OR DEATH BY EGFR AND ALBUMINURIA ARE SIMILAR WITH OR WITHOUT DIABETES. THESE FINDINGS UNDERSCORE THE IMPORTANCE OF KIDNEY DISEASE PER SE AS A PREDICTOR OF IMPORTANT CLINICAL OUTCOMES, REGARDLESS OF THE UNDERLYING CAUSE OF KIDNEY DISEASE. NEW BIOMARKERS OF DIABETIC KIDNEY DISEASE APPEAR TO HAVE ADDITIONAL PROGNOSTIC INFORMATION BEYOND THAT PROVIDED BY ALBUMINURIA. THESE MARKERS INCLUDE KIDNEY INJURY MOLECULE 1, LIVER FATTY ACID-BINDING PROTEIN, N-ACETYL-BETA-D-GLUCOSAMINIDASE, NEUTROPHIL GELATINASE-ASSOCIATED LIPOCALIN, BETA-TRACE PROTEIN, BETA(2)-MICROGLOBULIN, AND TUMOR NECROSIS FACTOR RECEPTORS 1 AND 2. MANY CONCEPTS ABOUT RISK FACTORS FOR CKD ILLUSTRATED IN THIS CHAPTER HAVE NOT CHANGED SINCE 1995, AND WHERE THEY HAVE, THOSE CHANGES ARE DISCUSSED. IN PARTICULAR, MAJOR ADVANCES HAVE BEEN MADE IN ELUCIDATING THE GENETIC AND EPIGENETIC COMPLEXITY OF CKD, WHICH CONTRIBUTED TO DEFINING CELLULAR METABOLIC MEMORY AND THE UNDERSTANDING OF THE LONGLASTING EFFECTS OF STRICT GLYCEMIC CONTROL OBSERVED IN PERSONS WITH TYPE 1 DIABETES OR TYPE 2 DIABETES. IMPROVEMENTS IN THE MANAGEMENT OF PERSONS WITH DIABETES AND CKD HAVE EXTENDED THE TIME COURSE FROM ONSET OF SEVERE ALBUMINURIA TO ESRD AND REDUCED THE OCCURRENCE OF CVD. IN TYPE 1 DIABETES, THE COMBINED DIABETES CONTROL AND COMPLICATIONS TRIAL (DCCT) AND ITS LONG-TERM FOLLOW-UP, THE EPIDEMIOLOGY OF DIABETES INTERVENTIONS AND COMPLICATIONS (EDIC) OBSERVATIONAL STUDY, INDICATED THAT INTENSIVE EARLY METABOLIC CONTROL REDUCED THE RISK OF IMPAIRED GFR BY 50% AND OF CVD OUTCOMES BY 42%, WITH A SPECIFIC 57% DECREASE IN MYOCARDIAL INFARCTION, STROKE, OR DEATH FROM CVD, EFFECTS THAT WERE PARTLY MEDIATED BY THE REDUCED INCIDENCE OF DIABETIC KIDNEY DISEASE. AMONG PERSONS WITH TYPE 2 DIABETES, A META-ANALYSIS OF RANDOMIZED CONTROLLED TRIALS INDICATED THAT MORE INTENSIVE GLYCEMIC CONTROL (GLYCOSYLATED HEMOGLOBIN [A1C] <7%) WAS ASSOCIATED WITH A SIGNIFICANT 10% REDUCTION IN ALBUMINURIA BUT HAD NO EFFECTS ON MORTALITY, KIDNEY FAILURE, OR OTHER VASCULAR OUTCOMES. THE ACTION TO CONTROL CARDIOVASCULAR RISK IN DIABETES (ACCORD) TRIAL, TARGETING AN A1C LEVEL <6.0% IN THE INTENSIVE INTERVENTION ARM, REPORTED AN INCREASED RISK OF CVD DEATH FOR INTENSIVE VERSUS CONVENTIONAL GLYCEMIC CONTROL, ALTHOUGH IT REMAINS UNCLEAR WHETHER THIS EFFECT WAS RELATED TO MORE HYPOGLYCEMIC EPISODES, THE USE OF ADDITIONAL HYPOGLYCEMIC MEDICINES, OR TO THE TARGET GLYCEMIC LEVEL ITSELF. LIKEWISE, THE MODEST GAINS IN INTERMEDIATE OUTCOMES IN THE INTENSIVE TREATMENT ARMS OF THE ACTION IN DIABETES AND VASCULAR DISEASE: PRETERAX AND DIAMICRON MODIFIED RELEASE CONTROLLED EVALUATION (ADVANCE) AND THE VETERANS AFFAIRS DIABETES (VADT) TRIAL WERE COUNTERBALANCED BY A TWOFOLD TO THREEFOLD HIGHER RISK OF SEVERE HYPOGLYCEMIA. TOGETHER, THESE TRIALS INDICATE THAT GLYCEMIC CONTROL IS EXTREMELY USEFUL UP TO A POINT, BUT MORE AGGRESSIVE GLYCEMIC CONTROL MAY BE HARMFUL. SIMILARLY, FOR BLOOD PRESSURE CONTROL, 2014-2015 RECOMMENDATIONS BY THE GUIDELINE-WRITING GROUPS ENDORSE LESS INTENSIVE AND MORE INDIVIDUALIZED BLOOD PRESSURE TARGETS FOR DIABETES AND CKD THAN IN THE PAST. PERSONS WITH DIABETES AND CKD REQUIRE MULTIDISCIPLINARY MANAGEMENT INVOLVING A COMBINATION OF TREATMENTS AND BEHAVIORAL ADJUSTMENTS TO DELAY PROGRESSION OF CKD AND TO PREVENT THE ASSOCIATED COMPLICATIONS. THE STENO-2 STUDY, A LANDMARK PROSPECTIVE, RANDOMIZED TRIAL IN DENMARK, DEMONSTRATED THAT COMPARED WITH CONVENTIONAL TREATMENT, INTENSIVE MULTIFACTORIAL INTERVENTION LED TO 46% LOWER DEATH RATE, 56% LESS SEVERE ALBUMINURIA, 43% LOWER INCIDENCE OF DIABETIC RETINOPATHY, AND 47% LOWER INCIDENCE OF AUTONOMIC NEUROPATHY DURING THE 13.3-YEAR STUDY PERIOD. 2018 13 6540 30 TRANSCRIPTIONAL, EPIGENETIC, AND FUNCTIONAL REPROGRAMMING OF MONOCYTES FROM NON-HUMAN PRIMATES FOLLOWING CHRONIC ALCOHOL DRINKING. CHRONIC HEAVY DRINKING (CHD) OF ALCOHOL IS A KNOWN RISK FACTOR FOR INCREASED SUSCEPTIBILITY TO BACTERIAL AND VIRAL INFECTION AS WELL AS IMPAIRED WOUND HEALING. EVIDENCE SUGGESTS THAT THESE DEFECTS ARE MEDIATED BY A DYSREGULATED INFLAMMATORY RESPONSE ORIGINATING FROM MYELOID CELLS, NOTABLY MONOCYTES AND MACROPHAGES, BUT THE MECHANISMS REMAIN POORLY UNDERSTOOD. OUR ABILITY TO STUDY CHD IS IMPACTED BY THE COMPLEXITIES OF HUMAN DRINKING PATTERNS AND BEHAVIOR AS WELL AS COMORBIDITIES AND CONFOUNDING RISK FACTORS FOR PATIENTS WITH ALCOHOL USE DISORDERS. TO OVERCOME THESE CHALLENGES, WE UTILIZED A TRANSLATIONAL RHESUS MACAQUE MODEL OF VOLUNTARY ETHANOL SELF-ADMINISTRATION THAT CLOSELY RECAPITULATES HUMAN DRINKING PATTERNS AND CHRONICITY. IN THIS STUDY, WE EXAMINED THE EFFECTS OF CHD ON BLOOD MONOCYTES IN CONTROL AND CHD FEMALE MACAQUES AFTER 12 MONTHS OF DAILY ETHANOL CONSUMPTION. WHILE MONOCYTES FROM CHD FEMALE MACAQUES GENERATED A HYPER-INFLAMMATORY RESPONSE TO EX VIVO LPS STIMULATION, THEIR RESPONSE TO E. COLI WAS DAMPENED. IN DEPTH SCRNA-SEQ ANALYSIS OF PURIFIED MONOCYTES REVEALED SIGNIFICANT SHIFTS IN CLASSICAL MONOCYTE SUBSETS WITH ACCUMULATION OF CELLS EXPRESSING MARKERS OF HYPOXIA (HIF1A) AND INFLAMMATION (NFKB SIGNALING PATHWAY) IN CHD MACAQUES. THE INCREASED PRESENCE OF MONOCYTE SUBSETS SKEWED TOWARDS INFLAMMATORY PHENOTYPES WAS COMPLEMENTED BY EPIGENETIC ANALYSIS, WHICH REVEALED HIGHER ACCESSIBILITY OF PROMOTER REGIONS THAT REGULATE GENES INVOLVED IN CYTOKINE SIGNALING PATHWAYS. COLLECTIVELY, DATA PRESENTED IN THIS MANUSCRIPT DEMONSTRATE THAT CHD SHIFTS CLASSICAL MONOCYTE SUBSET COMPOSITION AND PRIMES THE MONOCYTES TOWARDS A MORE HYPER-INFLAMMATORY RESPONSE TO LPS, BUT COMPROMISED PATHOGEN RESPONSE. 2021 14 6406 34 THE SEARCH FOR RELIABLE BIOMARKERS OF DISEASE IN MULTIPLE CHEMICAL SENSITIVITY AND OTHER ENVIRONMENTAL INTOLERANCES. WHILST FACING A WORLDWIDE FAST INCREASE OF FOOD AND ENVIRONMENTAL ALLERGIES, THE MEDICAL COMMUNITY IS ALSO CONFRONTED WITH ANOTHER INHOMOGENEOUS GROUP OF ENVIRONMENT-ASSOCIATED DISABLING CONDITIONS, INCLUDING MULTIPLE CHEMICAL SENSITIVITY (MCS), FIBROMYALGIA, CHRONIC FATIGUE SYNDROME, ELECTRIC HYPERSENSITIVITY, AMALGAM DISEASE AND OTHERS. THESE SHARE THE FEATURES OF POLY-SYMPTOMATIC MULTI-ORGAN CUTANEOUS AND SYSTEMIC MANIFESTATIONS, WITH POSTULATED INHERITED/ACQUIRED IMPAIRED METABOLISM OF CHEMICAL/PHYSICAL/NUTRITIONAL XENOBIOTICS, TRIGGERING ADVERSE REACTIONS AT EXPOSURE LEVELS FAR BELOW TOXICOLOGICALLY-RELEVANT VALUES, OFTEN IN THE ABSENCE OF CLEAR-CUT ALLERGOLOGIC AND/OR IMMUNOLOGIC INVOLVEMENT. DUE TO THE LACK OF PROVEN PATHOGENIC MECHANISMS GENERATING MEASURABLE DISEASE BIOMARKERS, THESE ENVIRONMENTAL HYPERSENSITIVITIES ARE GENERALLY IGNORED BY SANITARY AND SOCIAL SYSTEMS, AS PSYCHOGENIC OR "MEDICALLY UNEXPLAINED SYMPTOMS". THE UNCONTROLLED APPLICATION OF DIAGNOSTIC AND TREATMENT PROTOCOLS NOT CORRESPONDING TO ACCEPTABLE LEVELS OF VALIDATION, SAFETY, AND CLINICAL EFFICACY, TO A STEADILY INCREASING NUMBER OF PATIENTS DEMANDING ASSISTANCE, OCCURS IN MANY COUNTRIES IN THE ABSENCE OF EVIDENCE-BASED GUIDELINES. HERE WE REVISE AVAILABLE INFORMATION SUPPORTING THE ORGANIC NATURE OF THESE CLINICAL CONDITIONS. FOLLOWING INTENSE RESEARCH ON GENE POLYMORPHISMS OF PHASE I/II DETOXIFICATION ENZYME GENES, SO FAR STATISTICALLY INCONCLUSIVE, EPIGENETIC AND METABOLIC FACTORS ARE UNDER INVESTIGATION, IN PARTICULAR FREE RADICAL/ANTIOXIDANT HOMEOSTASIS DISTURBANCES. THE FINDING OF RELEVANT ALTERATIONS OF CATALASE, GLUTATHIONE-TRANSFERASE AND PEROXIDASE DETOXIFYING ACTIVITIES SIGNIFICANTLY CORRELATING WITH CLINICAL MANIFESTATIONS OF MCS, HAS RECENTLY REGISTERED SOME PROGRESS TOWARDS THE IDENTIFICATION OF RELIABLE BIOMARKERS OF DISEASE ONSET, PROGRESSION, AND TREATMENT OUTCOMES. 2011 15 2772 44 EXTRACELLULAR ATP AND NEURODEGENERATION. ATP IS A POTENT SIGNALING MOLECULE ABUNDANTLY PRESENT IN THE CNS. IT ELICITS A WIDE ARRAY OF PHYSIOLOGICAL EFFECTS AND IS REGARDED AS THE PHYLOGENETICALLY MOST ANCIENT EPIGENETIC FACTOR PLAYING CRUCIAL BIOLOGICAL ROLES IN SEVERAL DIFFERENT TISSUES. THESE CAN RANGE FROM NEUROTRANSMISSION, SMOOTH MUSCLE CONTRACTION, CHEMOSENSORY SIGNALING, SECRETION AND VASODILATATION, TO MORE COMPLEX PHENOMENA SUCH AS IMMUNE RESPONSES, PAIN, MALE REPRODUCTION, FERTILIZATION AND EMBRYONIC DEVELOPMENT. ATP IS RELEASED INTO THE EXTRACELLULAR SPACE EITHER EXOCYTOTICALLY OR FROM DAMAGED AND DYING CELLS. IT IS OFTEN CO-RELEASED WITH OTHER NEUROTRANSMITTERS AND IT CAN INTERACT WITH GROWTH FACTORS AT BOTH RECEPTOR- AND/OR SIGNAL TRANSDUCTION-LEVEL. ONCE IN THE EXTRACELLULAR ENVIRONMENT, ATP BINDS TO SPECIFIC RECEPTORS TERMED P2. BASED ON PHARMACOLOGICAL PROFILES, ON SELECTIVITY OF COUPLING TO SECOND-MESSENGER PATHWAYS AND ON MOLECULAR CLONING, TWO MAIN SUBCLASSES WITH MULTIPLE SUBTYPES HAVE BEEN DISTINGUISHED. THEY ARE P2X, I.E. FAST CATION-SELECTIVE RECEPTOR CHANNELS (NA+, K+, CA2+), POSSESSING LOW AFFINITY FOR ATP AND RESPONSIBLE FOR FAST EXCITATORY NEUROTRANSMISSION, AND P2Y, I.E. SLOW G PROTEIN-COUPLED METABOTROPIC RECEPTORS, POSSESSING HIGHER AFFINITY FOR THE LIGAND. IN THE NERVOUS SYSTEM, THEY ARE BROADLY EXPRESSED IN BOTH NEURONS AND GLIAL CELLS AND CAN MEDIATE DUAL EFFECTS: SHORT-TERM SUCH AS NEUROTRANSMISSION, AND LONG-TERM SUCH AS TROPHIC ACTIONS. SINCE MASSIVE EXTRACELLULAR RELEASE OF ATP OFTEN OCCURS AFTER METABOLIC STRESS, BRAIN ISCHEMIA AND TRAUMA, PURINERGIC MECHANISMS ARE ALSO CORRELATED TO AND INVOLVED IN THE ETIOPATHOLOGY OF MANY NEURODEGENERATIVE CONDITIONS. FURTHERMORE, EXTRACELLULAR ATP PER SE IS TOXIC FOR PRIMARY NEURONAL DISSOCIATED AND ORGANOTYPIC CNS CULTURES FROM CORTEX, STRIATUM AND CEREBELLUM AND P2 RECEPTORS CAN MEDIATE AND AGGRAVATE HYPOXIC SIGNALING IN MANY CNS NEURONS. CONVERSELY, SEVERAL P2 RECEPTOR ANTAGONISTS ABOLISH THE CELL DEATH FATE OF PRIMARY NEURONAL CULTURES EXPOSED TO EXCESSIVE GLUTAMATE, SERUM/POTASSIUM DEPRIVATION, HYPOGLYCEMIA AND CHEMICAL HYPOXIA. IN PARALLEL WITH THESE DETRIMENTAL EFFECTS, ALSO TROPHIC FUNCTIONS HAVE BEEN EXTENSIVELY DESCRIBED FOR EXTRACELLULAR PURINES (BOTH FOR NEURONAL AND NON-NEURONAL CELLS), BUT THESE MIGHT EITHER AGGRAVATE OR AMELIORATE THE NORMAL CELLULAR CONDITIONS. IN SUMMARY, EXTRACELLULAR ATP PLAYS A VERY COMPLEX ROLE NOT ONLY IN THE REPAIR, REMODELING AND SURVIVAL OCCURRING IN THE NERVOUS SYSTEM, BUT EVEN IN CELL DEATH AND THIS CAN OCCUR EITHER AFTER NORMAL DEVELOPMENTAL CONDITIONS, AFTER INJURY, OR ACUTE AND CHRONIC DISEASES. 2003 16 5815 32 STRESS AND GLUCOCORTICOID RECEPTOR TRANSCRIPTIONAL PROGRAMMING IN TIME AND SPACE: IMPLICATIONS FOR THE BRAIN-GUT AXIS. BACKGROUND: CHRONIC PSYCHOLOGICAL STRESS IS ASSOCIATED WITH ENHANCED ABDOMINAL PAIN AND ALTERED INTESTINAL BARRIER FUNCTION THAT MAY RESULT FROM A PERTURBATION IN THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS. THE GLUCOCORTICOID RECEPTOR (GR) EXPLOITS DIVERSE MECHANISMS TO ACTIVATE OR SUPPRESS CONGENERIC GENE EXPRESSION, WITH REGULATORY VARIATION ASSOCIATED WITH STRESS-RELATED DISORDERS IN PSYCHIATRY AND GASTROENTEROLOGY. PURPOSE: DURING ACUTE AND CHRONIC STRESS, CORTICOTROPIN-RELEASING HORMONE DRIVES SECRETION OF ADRENOCORTICOTROPIC HORMONE FROM THE PITUITARY, ULTIMATELY LEADING TO THE RELEASE OF CORTISOL (HUMAN) AND CORTICOSTERONE (RODENT) FROM THE ADRENAL GLANDS. CORTISOL BINDS WITH THE GR IN THE CYTOSOL, TRANSLOCATES TO THE NUCLEUS, AND ACTIVATES THE NR3C1 (NUCLEAR RECEPTOR SUBFAMILY 3, GROUP C, MEMBER 1 [GR]) GENE. THIS REVIEW FOCUSES ON THE RAPIDLY DEVELOPING OBSERVATIONS THAT CORTISOL IS RESPONSIBLE FOR DRIVING CIRCADIAN AND ULTRADIAN BURSTS OF TRANSCRIPTIONAL ACTIVITY IN THE CLOCK (CLOCK CIRCADIAN REGULATOR) AND PER (PERIOD CIRCADIAN CLOCK 1) GENE FAMILIES, AND THIS RHYTHM IS DISRUPTED IN MAJOR DEPRESSIVE DISORDER, BIPOLAR DISORDER, AND STRESS-RELATED GASTROINTESTINAL AND IMMUNE DISORDERS. GLUCOCORTICOID RECEPTOR REGULATES DIFFERENT SETS OF TRANSCRIPTS IN A TISSUE-SPECIFIC MANNER, THROUGH PULSATILE WAVES OF GENE EXPRESSION THAT INCLUDES OCCUPANCY OF GLUCOCORTICOID RESPONSE ELEMENTS LOCATED WITHIN CONSTITUTIVELY OPEN SPATIAL DOMAINS IN CHROMATIN. EMERGING EVIDENCE SUPPORTS A POTENTIALLY PIVOTAL ROLE FOR EPIGENETIC REGULATION OF HOW GR INTERACTS WITH OTHER CHROMATIN REGULATORS TO CONTROL THE EXPRESSION OF ITS TARGET GENES. DYSREGULATION OF THE CENTRAL AND PERIPHERAL GR REGULOME HAS POTENTIALLY SIGNIFICANT CONSEQUENCES FOR STRESS-RELATED DISORDERS AFFECTING THE BRAIN-GUT AXIS. 2016 17 169 28 ABNORMALITIES OF AMPK ACTIVATION AND GLUCOSE UPTAKE IN CULTURED SKELETAL MUSCLE CELLS FROM INDIVIDUALS WITH CHRONIC FATIGUE SYNDROME. BACKGROUND: POST EXERTIONAL MUSCLE FATIGUE IS A KEY FEATURE IN CHRONIC FATIGUE SYNDROME (CFS). ABNORMALITIES OF SKELETAL MUSCLE FUNCTION HAVE BEEN IDENTIFIED IN SOME BUT NOT ALL PATIENTS WITH CFS. TO TRY TO LIMIT POTENTIAL CONFOUNDERS THAT MIGHT CONTRIBUTE TO THIS CLINICAL HETEROGENEITY, WE DEVELOPED A NOVEL IN VITRO SYSTEM THAT ALLOWS COMPARISON OF AMP KINASE (AMPK) ACTIVATION AND METABOLIC RESPONSES TO EXERCISE IN CULTURED SKELETAL MUSCLE CELLS FROM CFS PATIENTS AND CONTROL SUBJECTS. METHODS: SKELETAL MUSCLE CELL CULTURES WERE ESTABLISHED FROM 10 SUBJECTS WITH CFS AND 7 AGE-MATCHED CONTROLS, SUBJECTED TO ELECTRICAL PULSE STIMULATION (EPS) FOR UP TO 24H AND EXAMINED FOR CHANGES ASSOCIATED WITH EXERCISE. RESULTS: IN THE BASAL STATE, CFS CULTURES SHOWED INCREASED MYOGENIN EXPRESSION BUT DECREASED IL6 SECRETION DURING DIFFERENTIATION COMPARED WITH CONTROL CULTURES. CONTROL CULTURES SUBJECTED TO 16 H EPS SHOWED A SIGNIFICANT INCREASE IN BOTH AMPK PHOSPHORYLATION AND GLUCOSE UPTAKE COMPARED WITH UNSTIMULATED CELLS. IN CONTRAST, CFS CULTURES SHOWED NO INCREASE IN AMPK PHOSPHORYLATION OR GLUCOSE UPTAKE AFTER 16 H EPS. HOWEVER, GLUCOSE UPTAKE REMAINED RESPONSIVE TO INSULIN IN THE CFS CELLS POINTING TO AN EXERCISE-RELATED DEFECT. IL6 SECRETION IN RESPONSE TO EPS WAS SIGNIFICANTLY REDUCED IN CFS COMPARED WITH CONTROL CULTURES AT ALL TIME POINTS MEASURED. CONCLUSION: EPS IS AN EFFECTIVE MODEL FOR ELICITING MUSCLE CONTRACTION AND THE METABOLIC CHANGES ASSOCIATED WITH EXERCISE IN CULTURED SKELETAL MUSCLE CELLS. WE FOUND FOUR MAIN DIFFERENCES IN CULTURED SKELETAL MUSCLE CELLS FROM SUBJECTS WITH CFS; INCREASED MYOGENIN EXPRESSION IN THE BASAL STATE, IMPAIRED ACTIVATION OF AMPK, IMPAIRED STIMULATION OF GLUCOSE UPTAKE AND DIMINISHED RELEASE OF IL6. THE RETENTION OF THESE DIFFERENCES IN CULTURED MUSCLE CELLS FROM CFS SUBJECTS POINTS TO A GENETIC/EPIGENETIC MECHANISM, AND PROVIDES A SYSTEM TO IDENTIFY NOVEL THERAPEUTIC TARGETS. 2015 18 837 43 CHEMICALLY INDUCED RENAL TUBULE TUMORS IN THE LABORATORY RAT AND MOUSE: REVIEW OF THE NCI/NTP DATABASE AND CATEGORIZATION OF RENAL CARCINOGENS BASED ON MECHANISTIC INFORMATION. THE INCIDENCE OF RENAL TUBULE CARCINOGENESIS IN MALE AND FEMALE RATS OR MICE WITH 69 CHEMICALS FROM THE 513 BIOASSAYS CONDUCTED TO DATE BY THE NCI/NTP HAS BEEN COLLATED, THE CHEMICALS CATEGORIZED, AND THE RELATIONSHIP BETWEEN CARCINOGENESIS AND RENAL TUBULE HYPERPLASIA AND EXACERBATION OF THE SPONTANEOUS, AGE-RELATED RODENT DISEASE CHRONIC PROGRESSIVE NEPHROPATHY (CPN) EXAMINED. WHERE INFORMATION ON MECHANISM OR MODE OF ACTION EXISTS, THE CHEMICALS HAVE BEEN CATEGORIZED BASED ON THEIR ABILITY TO DIRECTLY OR INDIRECTLY INTERACT WITH RENAL DNA, OR ON THEIR ACTIVITY VIA EPIGENETIC PATHWAYS INVOLVING EITHER DIRECT OR INDIRECT CYTOTOXICITY WITH REGENERATIVE HYPERPLASIA, OR EXACERBATION OF CPN. NINE CHEMICALS WERE IDENTIFIED AS DIRECTLY INTERACTING WITH DNA, WITH SIX OF THESE PRODUCING RENAL TUBULE TUMORS AT HIGH INCIDENCE IN RATS OF BOTH SEXES, AND IN SOME CASES ALSO IN MICE. OCHRATOXIN A WAS THE MOST POTENT COMPOUND IN THIS GROUP, PRODUCING A HIGH TUMOR INCIDENCE AT VERY LOW DOSES, OFTEN WITH METASTASIS. THREE CHEMICALS WERE DISCUSSED IN THE CONTEXT OF INDIRECT DNA DAMAGE MEDIATED BY AN OXIDATIVE FREE RADICAL MECHANISM, ONE OF THESE BEING FROM THE NTP DATABASE. A THIRD CATEGORY INCLUDED FOUR CHEMICALS THAT HAD THE POTENTIAL TO CAUSE DNA DAMAGE FOLLOWING CONJUGATION WITH GLUTATHIONE AND SUBSEQUENT ENZYMATIC ACTIVATION TO A REACTIVE SPECIES, USUALLY A THIOL-CONTAINING ENTITY. TWO CHEMICALS WERE ALLOCATED INTO THE CATEGORY INVOLVING A DIRECT CYTOTOXIC ACTION ON THE RENAL TUBULE FOLLOWED BY SUSTAINED COMPENSATORY CELL PROLIFERATION, WHILE NINE WERE INCLUDED IN A GROUP WHERE THE CELL LOSS AND SUSTAINED INCREASE IN RENAL TUBULE CELL TURNOVER WERE DEPENDENT ON LYSOSOMAL ACCUMULATION OF THE MALE RAT-SPECIFIC PROTEIN, ALPHA2MU-GLOBULIN. IN A SIXTH CATEGORY, MORPHOLOGIC EVIDENCE ON TWO CHEMICALS INDICATED THAT THE RENAL TUMORS WERE A CONSEQUENCE OF EXACERBATED CPN. FOR THE REMAINING CHEMICALS, THERE WERE NO PERTINENT DATA ENABLING ASSIGNMENT TO A MECHANISTIC CATEGORY. ACCORDINGLY, THESE CHEMICALS, ACTING THROUGH AN AS YET UNKNOWN MECHANISM, WERE GROUPED AS EITHER BEING ASSOCIATED WITH AN ENHANCEMENT OF CPN (CATEGORY 7, 16 CHEMICALS), OR NOT ASSOCIATED WITH ENHANCED CPN (CATEGORY 8, 4 CHEMICALS). A NINTH CATEGORY DEALT WITH 11 CHEMICALS THAT WERE REGARDED AS PRODUCING INCREASES IN RENAL TUBULE TUMORS THAT DID NOT REACH STATISTICAL SIGNIFICANCE. A 10TH CATEGORY DISCUSSED 6 CHEMICALS THAT INDUCED RENAL TUMORS IN MICE BUT NOT IN RATS, PLUS 8 CHEMICALS THAT PRODUCED A LOW INCIDENCE OF RENAL TUBULE TUMORS IN MICE THAT DID NOT REACH STATISTICAL SIGNIFICANCE. AS MORE MECHANISTIC DATA ARE GENERATED, SOME CHEMICALS WILL INEVITABLY BE PLACED IN DIFFERENT GROUPS, PARTICULARLY THOSE FROM CATEGORIES 7 AND 8. A LARGE NUMBER OF CHEMICALS IN THE SERIES EXACERBATED CPN, BUT THOSE IN CATEGORY 7 ESPECIALLY MAY BE CANDIDATES FOR INCLUSION IN CATEGORY 6 WHEN FURTHER INFORMATION IS GLEANED FROM THE RELEVANT NTP STUDIES. ALSO, NEW DATA ON SPECIFIC CHEMICALS WILL PROBABLY EXPAND CATEGORY 5 AS CYTOTOXICITY AND CELL REGENERATION ARE IDENTIFIED AS OBLIGATORY STEPS IN RENAL CARCINOGENESIS IN MORE CASES. ADDITIONAL CONFIRMATORY OUTCOMES ARISING FROM THIS REVIEW ARE THAT METASTASES FROM RENAL TUBULE TUMORS, WHILE ENCOUNTERED WITH CHEMICALS CAUSING DNA DAMAGE, ARE RARE WITH THOSE ACTING THROUGH AN EPIGENETIC PATHWAY, WITH THE EXCEPTION BEING FUMONISIN B1; THAT MALE RATS AND MICE ARE GENERALLY MORE SUSCEPTIBLE THAN FEMALE RATS AND MICE TO CHEMICAL INDUCTION OF RENAL TUBULE TUMORS; AND THAT A BACKGROUND OF ATYPICAL TUBULE HYPERPLASIA IS A USEFUL INDICATOR REFLECTING A CHEMICALLY ASSOCIATED RENAL TUBULE TUMOR RESPONSE. WITH RESPECT TO RENAL TUBULE TUMORS AND HUMAN RISK ASSESSMENT, CHEMICALS IN CATEGORIES 1 AND 2, AND POSSIBLY 3, WOULD CURRENTLY BE JUDGED BY LINEAR DEFAULT METHODS; CHEMICALS IN CATEGORY 4 (AND PROBABLY SOME IN CATEGORY 3) AS EXHIBITING A THRESHOLD OF ACTIVITY WARRANTING THE BENCHMARK APPROACH; AND THOSE IN CATEGORIES 5 AND 6 AS REPRESENTING MECHANISMS THAT HAVE NO RELEVANCE FOR EXTRAPOLATION TO HUMANS. 2004 19 3287 52 HIERARCHICAL AND CYBERNETIC NATURE OF BIOLOGIC SYSTEMS AND THEIR RELEVANCE TO HOMEOSTATIC ADAPTATION TO LOW-LEVEL EXPOSURES TO OXIDATIVE STRESS-INDUCING AGENTS. DURING EVOLUTION IN AN AEROBIC ENVIRONMENT, MULTICELLULAR ORGANISMS SURVIVED BY ADAPTIVE RESPONSES TO BOTH THE ENDOGENOUS OXIDATIVE METABOLISM IN THE CELLS OF THE ORGANISM AND THE CHEMICALS AND LOW-LEVEL RADIATION TO WHICH THEY HAD BEEN EXPOSED. THE DEFENSE REPERTOIRE EXISTS AT ALL LEVELS OF THE BIOLOGICAL HIERARCHY--FROM THE MOLECULAR AND BIOCHEMICAL LEVEL TO THE CELLULAR AND TISSUE LEVEL TO THE ORGAN AND ORGAN SYSTEM LEVEL. CELLS CONTAIN PREVENTIVE ANTIOXIDANTS TO SUPPRESS OXIDATIVE DAMAGE TO MEMBRANES. CELLS ALSO CONTAIN PROTEINS AND DNA; BUILT-IN REDUNDANCIES FOR DAMAGED MOLECULES AND ORGANELLES; TIGHTLY COUPLED REDOX SYSTEMS; POOLS OF REDUCTANTS; ANTIOXIDANTS; DNA REPAIR MECHANISMS AND SENSITIVE SENSOR MOLECULES SUCH AS NUCLEAR FACTOR KAPPA BETA; AND SIGNAL TRANSDUCTION MECHANISMS AFFECTING BOTH TRANSCRIPTION AND POST-TRANSLATIONAL MODIFICATION OF PROTEINS NEEDED TO COPE WITH OXIDATIVE STRESS. THE BIOLOGIC CONSEQUENCES OF THE LOW-LEVEL RADIATION THAT EXCEEDS THE BACKGROUND LEVEL OF OXIDATIVE DAMAGE COULD BE NECROSIS OR APOPTOSIS, CELL PROLIFERATION, OR CELL DIFFERENTIATION. THESE EFFECTS ARE TRIGGERED BY OXIDATIVE STRESS-INDUCED SIGNAL TRANSDUCTION MECHANISMS--AN EPIGENETIC, NOT GENOTOXIC, PROCESS. IF THE END POINTS OF CELL PROLIFERATION, DIFFERENTIATION, OR CELL DEATH ARE NOT SEEN AT FREQUENCIES ABOVE BACKGROUND LEVELS IN AN ORGANISM, IT IS UNLIKELY THAT LOW-LEVEL RADIATION WOULD PLAY A ROLE IN THE MULTISTEP PROCESSES OF CHRONIC DISEASES SUCH AS CANCER. THE MECHANISM LINKED TO HOMEOSTATIC REGULATION OF PROLIFERATION AND ADAPTIVE FUNCTIONS IN A MULTICELLULAR ORGANISM COULD PROVIDE PROTECTION OF ANY ONE CELL RECEIVING DEPOSITED ENERGY BY THE RADIATION TRACT THROUGH THE SHARING OF REDUCTANTS AND BY TRIGGERING APOPTOSIS OF TARGET STEM CELLS. EXAMPLES OF THE ROLE OF GAP JUNCTIONAL INTERCELLULAR COMMUNICATION IN THE ADAPTIVE RESPONSE OF CELLS AND THE BYSTANDER EFFECT ILLUSTRATE HOW THE INTERACTION OF CELLS CAN MODULATE THE EFFECT OF RADIATION ON THE SINGLE CELL. 1998 20 1556 29 DNA METHYLATION MODIFICATIONS ASSOCIATED WITH CHRONIC FATIGUE SYNDROME. CHRONIC FATIGUE SYNDROME (CFS), ALSO KNOWN AS MYALGIC ENCEPHALOMYELITIS, IS A COMPLEX MULTIFACTORIAL DISEASE THAT IS CHARACTERIZED BY THE PERSISTENT PRESENCE OF FATIGUE AND OTHER PARTICULAR SYMPTOMS FOR A MINIMUM OF 6 MONTHS. SYMPTOMS FAIL TO DISSIPATE AFTER SUFFICIENT REST AND HAVE MAJOR EFFECTS ON THE DAILY FUNCTIONING OF CFS SUFFERERS. CFS IS A MULTI-SYSTEM DISEASE WITH A HETEROGENEOUS PATIENT POPULATION SHOWING A WIDE VARIETY OF FUNCTIONAL DISABILITIES AND ITS BIOLOGICAL BASIS REMAINS POORLY UNDERSTOOD. STABLE ALTERATIONS IN GENE FUNCTION IN THE IMMUNE SYSTEM HAVE BEEN REPORTED IN SEVERAL STUDIES OF CFS. EPIGENETIC MODIFICATIONS HAVE BEEN IMPLICATED IN LONG-TERM EFFECTS ON GENE FUNCTION, HOWEVER, TO OUR KNOWLEDGE, GENOME-WIDE EPIGENETIC MODIFICATIONS ASSOCIATED WITH CFS HAVE NOT BEEN EXPLORED. WE EXAMINED THE DNA METHYLOME IN PERIPHERAL BLOOD MONONUCLEAR CELLS ISOLATED FROM CFS PATIENTS AND HEALTHY CONTROLS USING THE ILLUMINA HUMANMETHYLATION450 BEADCHIP ARRAY, CONTROLLING FOR INVARIANT PROBES AND PROBES OVERLAPPING POLYMORPHIC SEQUENCES. GENE ONTOLOGY (GO) AND NETWORK ANALYSIS OF DIFFERENTIALLY METHYLATED GENES WAS PERFORMED TO DETERMINE POTENTIAL BIOLOGICAL PATHWAYS SHOWING CHANGES IN DNA METHYLATION IN CFS. WE FOUND AN INCREASED ABUNDANCE OF DIFFERENTIALLY METHYLATED GENES RELATED TO THE IMMUNE RESPONSE, CELLULAR METABOLISM, AND KINASE ACTIVITY. GENES ASSOCIATED WITH IMMUNE CELL REGULATION, THE LARGEST COORDINATED ENRICHMENT OF DIFFERENTIALLY METHYLATED PATHWAYS, SHOWED HYPOMETHYLATION WITHIN PROMOTERS AND OTHER GENE REGULATORY ELEMENTS IN CFS. THESE DATA ARE CONSISTENT WITH EVIDENCE OF MULTISYSTEM DYSREGULATION IN CFS AND IMPLICATE THE INVOLVEMENT OF DNA MODIFICATIONS IN CFS PATHOLOGY. 2014