1 2866 120 FUNCTIONAL ADULT ACETYLCHOLINE RECEPTOR DEVELOPS INDEPENDENTLY OF MOTOR INNERVATION IN SOL 8 MOUSE MUSCLE CELL LINE. WE HAVE DEFINED CULTURE CONDITIONS, USING A FEEDER LAYER OF CELLS FROM THE EMBRYONIC MESENCHYMAL CELL LINE, 10T1/2 AND A SERUM-FREE MEDIUM, WHICH ALLOW CELLS FROM THE MOUSE MYOGENIC CELL LINE SOL 8 TO FORM CONTRACTING MYOTUBES FOR TWO WEEKS. UNDER THESE CULTURE CONDITIONS, SOL 8 MYOTUBES UNDERGO A MATURATION PROCESS CHARACTERIZED BY A SEQUENTIAL EXPRESSION OF TWO PHENOTYPES. AN EARLY PHENOTYPE IS TYPIFIED BY THE EXPRESSION OF THE NICOTINIC ACETYLCHOLINE RECEPTOR (ACHR) GAMMA-SUBUNIT TRANSCRIPTS AND THE PRESENCE OF LOW CONDUCTANCE ACH-ACTIVATED CHANNELS, TYPICAL OF EMBRYONIC ACHR. A LATE PHENOTYPE IS CHARACTERIZED BY THE EXPRESSION OF ACHR EPSILON-SUBUNIT TRANSCRIPTS, THE DECREASED ACCUMULATION OF GAMMA-SUBUNIT TRANSCRIPTS AND THE APPEARANCE OF HIGH CONDUCTANCE ACH-ACTIVATED CHANNELS, TYPICAL OF ADULT ACHR. THESE RESULTS INDICATE THAT THE EXPRESSION OF FUNCTIONAL ADULT TYPE ACHR DOES NOT REQUIRE THE PRESENCE OF THE MOTOR NERVE AND THEREFORE REPRESENTS AN INTRINSIC FEATURE OF THE SOL 8 MUSCLE CELLS. CHRONIC EXPOSURE OF THE CELLS TO THE VOLTAGE-SENSITIVE NA+ CHANNEL BLOCKING AGENT TETRODOTOXIN DOES NOT AFFECT THE APPEARANCE OF THE ACHR EPSILON-SUBUNIT TRANSCRIPTS BUT PREVENTS THE REDUCTION OF THE STEADY-STATE LEVEL OF THE ACHR GAMMA-SUBUNIT TRANSCRIPTS AND YIELDS A REDUCED PROPORTION OF THE ADULT TYPE CHANNELS. THUS, ACTIVITY SEEMS TO FACILITATE THE SWITCH FROM THE EMBRYONIC TO THE ADULT PHENOTYPE OF THE ACHR PROTEIN. THE SOL 8 CELL SYSTEM MIGHT BE USEFUL TO ANALYSE FURTHER THE GENETIC AND EPIGENETIC REGULATION OF MUSCLE FIBRE MATURATION IN MAMMALS. 1991 2 1475 25 DISTRIBUTION OF H3K27ME3, H3K9ME3, AND H3K4ME3 ALONG AUTOPHAGY-RELATED GENES HIGHLY EXPRESSED IN STARVED ZEBRAFISH MYOTUBES. THE ZEBRAFISH (DANIO RERIO) REMAINS THE TELEOST FISH OF CHOICE FOR BIOLOGICAL INVESTIGATIONS DUE TO THE VAST ARRAY OF MOLECULAR TOOLS AND RESOURCES AVAILABLE. TO BETTER UNDERSTAND THE EPIGENETIC REGULATION OF AUTOPHAGY, WE UTILIZED A PRIMARY MYOTUBE CULTURE SYSTEM GENERATED FROM ISOLATED MYOGENIC PRECURSOR CELLS (MPCS) FROM ZEBRAFISH GROWN UNDER STARVATION CONDITIONS USING A MEDIA DEVOID OF SERUM AND AMINO ACIDS. HERE, WE REPORT STARVATION-INDUCED REGULATION OF SEVERAL AUTOPHAGY-RELATED GENES (ATG) EXPRESSION AND PROFILE THE DISTRIBUTION OF H3K27ME3, H3K9ME3, AND H3K4ME3 MARKS ALONG LC3B, ATG4B AND P62/SQSTM1 LOCI. THESE DATA SUPPORT EPIGENETIC REGULATION OF AUTOPHAGY IN RESPONSE TO STARVATION THAT SUGGESTS A LEVEL OF REGULATION THAT CAN BE SUSTAINED FOR CHRONIC CONDITIONS VIA CHROMATIN MODIFICATION. 2017 3 350 28 ALTERED DYNAMICS OF LIPID METABOLISM IN MUSCLE CELLS FROM PATIENTS WITH IDIOPATHIC INFLAMMATORY MYOPATHY IS AMELIORATED BY 6 MONTHS OF TRAINING. KEY POINTS: REGULAR EXERCISE IMPROVES MUSCLE FUNCTIONAL CAPACITY AND CLINICAL STATE OF PATIENTS WITH IDIOPATHIC INFLAMMATORY MYOPATHY (IIM). IN OUR STUDY, WE USED AN IN VITRO MODEL OF HUMAN PRIMARY MUSCLE CELL CULTURES, DERIVED FROM IIM PATIENTS BEFORE AND AFTER A 6-MONTH INTENSIVE SUPERVISED TRAINING INTERVENTION TO ASSESS THE IMPACT OF DISEASE AND EXERCISE ON LIPID METABOLISM DYNAMICS. WE PROVIDE EVIDENCE THAT MUSCLE CELLS FROM IIM PATIENTS DISPLAY ALTERED DYNAMICS OF LIPID METABOLISM AND IMPAIRED ADAPTIVE RESPONSE TO SATURATED FATTY ACID LOAD COMPARED TO HEALTHY CONTROLS. A 6-MONTH INTENSIVE SUPERVISED EXERCISE TRAINING INTERVENTION IN PATIENTS WITH IIM MITIGATED DISEASE EFFECTS IN THEIR CULTURED MUSCLE CELLS, IMPROVING OR NORMALIZING THEIR CAPACITY TO HANDLE LIPIDS. THESE FINDINGS HIGHLIGHT THE PUTATIVE ROLE OF INTRINSIC METABOLIC DEFECTS OF SKELETAL MUSCLE IN THE PATHOGENESIS OF IIM AND THE POSITIVE IMPACT OF EXERCISE, MAINTAINED IN VITRO BY YET UNKNOWN EPIGENETIC MECHANISMS. ABSTRACT: EXERCISE IMPROVES SKELETAL MUSCLE FUNCTION, CLINICAL STATE AND QUALITY OF LIFE IN PATIENTS WITH IDIOPATHIC INFLAMMATORY MYOPATHY (IIM). OUR AIM WAS TO IDENTIFY DISEASE-RELATED METABOLIC PERTURBATIONS AND THE IMPACT OF EXERCISE IN SKELETAL MUSCLE CELLS OF IIM PATIENTS. PATIENTS UNDERWENT A 6-MONTH INTENSIVE SUPERVISED TRAINING INTERVENTION. MUSCLE FUNCTION, ANTHROPOMETRIC AND METABOLIC PARAMETERS WERE EXAMINED AND MUSCLE CELL CULTURES WERE ESTABLISHED (M. VASTUS LATERALIS; BERGSTROM NEEDLE BIOPSY) BEFORE AND AFTER TRAINING FROM PATIENTS AND SEDENTARY AGE/SEX/BODY MASS INDEX-MATCHED CONTROLS. [(14) C]PALMITATE WAS USED TO DETERMINE FAT OXIDATION AND LIPID SYNTHESIS (THIN LAYER CHROMATOGRAPHY). CELLS WERE EXPOSED TO A CHRONIC (3 DAYS) AND ACUTE (3 H) METABOLIC CHALLENGE (THE SATURATED FATTY ACID PALMITATE, 100 MUM). REDUCED OXIDATIVE (INTERMEDIATE METABOLITES, -49%, P = 0.034) AND NON-OXIDATIVE (DIGLYCERIDES, -38%, P = 0.013) LIPID METABOLISM WAS IDENTIFIED IN PALMITATE-TREATED MUSCLE CELLS FROM IIM PATIENTS COMPARED TO CONTROLS. THREE DAYS OF PALMITATE EXPOSURE ELICITED DISTINCT REGULATION OF OXIDATIVE PHOSPHORYLATION (OXPHOS) COMPLEX IV AND COMPLEX V/ATP SYNTHASE (P = 0.012/0.005) AND ADIPOSE TRIGLYCERIDE LIPASE IN PATIENTS COMPARED TO CONTROLS (P = 0.045) (IMMUNOBLOTTING). IMPORTANTLY, 6 MONTHS OF TRAINING IN IIM PATIENTS IMPROVED LIPID METABOLISM (CO(2) , P = 0.010; INTERMEDIATE METABOLITES, P = 0.041) AND ACTIVATION OF AMP KINASE (P = 0.007), AND NEARLY NORMALIZED PALMITATE-INDUCED CHANGES IN OXPHOS PROTEINS IN MYOTUBES FROM IIM PATIENTS, IN PARALLEL WITH IMPROVEMENTS OF PATIENTS' CLINICAL STATE. MYOTUBES FROM IIM PATIENTS DISPLAYED ALTERED DYNAMICS OF LIPID METABOLISM AND IMPAIRED RESPONSE TO METABOLIC CHALLENGE WITH SATURATED FATTY ACID. OUR OBSERVATIONS SUGGEST THAT METABOLIC DEFECTS INTRINSIC TO SKELETAL MUSCLE COULD REPRESENT NON-IMMUNE PATHOMECHANISMS, WHICH CAN CONTRIBUTE TO MUSCLE WEAKNESS IN IIM. A 6-MONTH TRAINING INTERVENTION MITIGATED DISEASE EFFECTS IN MUSCLE CELLS IN VITRO, INDICATING THE EXISTENCE OF EPIGENETIC REGULATORY MECHANISMS. 2021 4 3633 30 INCREASE IN HDAC9 SUPPRESSES MYOBLAST DIFFERENTIATION VIA EPIGENETIC REGULATION OF AUTOPHAGY IN HYPOXIA. EXTREMELY REDUCED OXYGEN (O(2)) LEVELS ARE DETRIMENTAL TO MYOGENIC DIFFERENTIATION AND MULTINUCLEATED MYOTUBE FORMATION, AND CHRONIC EXPOSURE TO HIGH-ALTITUDE HYPOXIA HAS BEEN REPORTED TO BE AN IMPORTANT FACTOR IN SKELETAL MUSCLE ATROPHY. HOWEVER, HOW CHRONIC HYPOXIA CAUSES MUSCLE DYSFUNCTION REMAINS UNKNOWN. IN THE PRESENT STUDY, WE FOUND THAT SEVERE HYPOXIA (1% O(2)) SIGNIFICANTLY INHIBITED THE FUNCTION OF C2C12 CELLS (FROM A MYOBLAST CELL LINE). IMPORTANTLY, THE IMPAIRMENT WAS CONTINUOUSLY MANIFESTED EVEN DURING CULTURE UNDER NORMOXIC CONDITIONS FOR SEVERAL PASSAGES. MECHANISTICALLY, WE REVEALED THAT HISTONE DEACETYLASES 9 (HDAC9), A MEMBER OF THE HISTONE DEACETYLASE FAMILY, WAS SIGNIFICANTLY INCREASED IN C2C12 CELLS UNDER HYPOXIC CONDITIONS, THEREBY INHIBITING INTRACELLULAR AUTOPHAGY LEVELS BY DIRECTLY BINDING TO THE PROMOTER REGIONS OF ATG7, BECLIN1, AND LC3. THIS PHENOMENON RESULTED IN THE SEQUENTIAL DEPHOSPHORYLATION OF GSK3BETA AND INACTIVATION OF THE CANONICAL WNT PATHWAY, IMPAIRING THE FUNCTION OF THE C2C12 CELLS. TAKEN TOGETHER, OUR RESULTS SUGGEST THAT HYPOXIA-INDUCED MYOBLAST DYSFUNCTION IS DUE TO ABERRANT EPIGENETIC REGULATION OF AUTOPHAGY, AND OUR EXPERIMENTAL EVIDENCE REVEALS THE POSSIBLE MOLECULAR PATHOGENESIS RESPONSIBLE FOR SOME MUSCLE DISEASES CAUSED BY CHRONIC HYPOXIA AND SUGGESTS A POTENTIAL THERAPEUTIC OPTION. 2019 5 5679 24 SHORT- AND LONG-TERM HINDLIMB IMMOBILIZATION AND RELOADING: PROFILE OF EPIGENETIC EVENTS IN GASTROCNEMIUS. SKELETAL MUSCLE DYSFUNCTION AND ATROPHY ARE CHARACTERISTIC FEATURES ACCOMPANYING CHRONIC CONDITIONS. EPIGENETIC EVENTS REGULATE MUSCLE MASS AND FUNCTION MAINTENANCE. WE HYPOTHESIZED THAT THE PATTERN OF EPIGENETIC EVENTS (MUSCLE-ENRICHED MICRORNAS AND HISTONE ACETYLATION) AND ACETYLATION OF TRANSCRIPTION FACTORS KNOWN TO SIGNAL MUSCLE WASTING MAY DIFFER BETWEEN EARLY- AND LATE-TIME POINTS IN SKELETAL MUSCLES OF MICE EXPOSED TO HINDLIMB IMMOBILIZATION (I) AND RECOVERY FOLLOWING I. BODY AND MUSCLE WEIGHTS, GRIP STRENGTH, MUSCLE-ENRICHED MICRORNAS, HISTONE DEACETYLASES (HDACS), ACETYLATION OF PROTEINS, HISTONES, AND TRANSCRIPTION FACTORS (TF), MYOGENIC TF FACTORS, AND MUSCLE PHENOTYPE WERE ASSESSED IN GASTROCNEMIUS OF MICE EXPOSED TO PERIODS (1, 2, 3, 7, 15, AND 30 DAYS, I GROUPS) OF HINDLIMB IMMOBILIZATION, AND IN THOSE EXPOSED TO RELOADING FOR DIFFERENT PERIODS OF TIME (1, 3, 7, 15, AND 30 DAYS, R GROUPS) FOLLOWING 7-DAY IMMOBILIZATION. COMPARED TO NON-IMMOBILIZED CONTROLS, MUSCLE WEIGHT, LIMB STRENGTH, MICRORNAS, ESPECIALLY MIR-486, SIRT1 LEVELS, AND SLOW- AND FAST-TWITCH CROSS-SECTIONAL AREAS WERE DECREASED IN MICE OF I GROUPS, WHEREAS PAX7 AND ACETYLATED FOXO1 AND FOXO3 LEVELS WERE INCREASED. MUSCLE RELOADING FOLLOWING SPLINT REMOVAL IMPROVED MUSCLE MASS LOSS, STRENGTH, AND FIBER ATROPHY, BY INCREASING MICRORNAS, PARTICULARLY MIR-486, AND SIRT1 CONTENT, WHILE DECREASING ACETYLATED FOXO1 AND FOXO3 LEVELS. IN THIS MOUSE MODEL OF DISUSE MUSCLE ATROPHY, MUSCLE-ENRICHED MICRORNAS, ESPECIALLY MIR-486, THROUGH PAX7 REGULATION DELAYED MUSCLE CELL DIFFERENTIATION FOLLOWING UNLOADING OF GASTROCNEMIUS MUSCLE. ACETYLATION OF FOXO1 AND 3 SEEMED TO DRIVE MUSCLE MASS LOSS AND ATROPHY, WHILE DEACETYLATION OF THESE FACTORS THROUGH SIRT1 WOULD ENABLE THE MUSCLE FIBERS TO REGENERATE. J. CELL. PHYSIOL. 232: 1415-1427, 2017. (C) 2016 WILEY PERIODICALS, INC. 2017 6 2787 32 EZH2-MEDIATED EPIGENETIC MODIFICATION IS REQUIRED FOR ALLOGENEIC T CELL-INDUCED LUPUS DISEASE. BACKGROUND: THE MECHANISMS INVOLVED IN THE PATHOGENESIS OF AUTOIMMUNE DISORDERS, INCLUDING SYSTEMIC LUPUS ERYTHEMATOSUS (SLE), HAVE NOT BEEN FULLY ELUCIDATED. SOME OF THESE MECHANISMS INVOLVE EPIGENETIC REGULATION OF GENE EXPRESSION. THE HISTONE METHYLTRANSFERASE EZH2 CONTRIBUTES TO EPIGENETIC REGULATION OF GENE EXPRESSION, IS HIGHLY EXPRESSED IN GERMINAL CENTER (GC) B CELLS AND FOLLICULAR T HELPER (T(FH)) CELLS, AND MAY BE INVOLVED IN LUPUS PATHOGENESIS. METHODS: THE MURINE BM12 MODEL OF LUPUS-LIKE CHRONIC GRAFT VERSUS HOST DISEASE (CGVHD) WAS INDUCED BY INTRA-PERITONEAL INJECTION OF NEGATIVELY ISOLATED ALLOGENEIC CD4(+) T CELLS. LUPUS-LIKE DISEASE DEVELOPMENT WAS MONITORED BY ELISA DETERMINATION OF SERUM ANTI-DSDNA AND ANTI-CHROMATIN ANTIBODY TITERS. IMMUNE CELL ACTIVATION AND EZH2 EXPRESSION WERE EVALUATED BY FLOW CYTOMETRY AND WESTERN BLOTTING. RESULTS: DECREASED AUTOANTIBODY PRODUCTION AND GC FORMATION ARE OBSERVED WHEN EZH2-DEFICIENT CD4(+) T CELLS ARE USED INSTEAD OF WILD-TYPE (WT) TO INDUCE CGVHD AND WHEN MICE THAT RECEIVE ALLOGENEIC WT DONOR T CELLS TO INDUCE CGVHD ARE TREATED WITH GSK503, AN EZH2-SPECIFIC INHIBITOR. IN THE BM12 CGVHD MODEL, WT DONOR T CELLS ARE NORMALLY FULLY ACTIVATED 1 WEEK AFTER INFUSION INTO AN ALLOGENEIC HOST, EXHIBIT A T(FH) CELL (PD-1(HI)/CXCR5(HI)) PHENOTYPE WITH UPREGULATED EZH2, AND ACTIVATE B CELLS TO FORM GERMINAL CENTERS (GCS). IN CONTRAST, EZH2-DEFICIENT DONOR T CELLS GENERATE FEWER T(FH) CELLS THAT FAIL TO ACTIVATE B CELLS OR PROMOTE GC FORMATION. DESPITE SIMILAR T-INDEPENDENT, LPS-INDUCED B CELL RESPONSES, OVA-IMMUNIZED CD4.EZH2-KO MICE HAD A SKEWED LOW-AFFINITY IGM PHENOTYPE IN COMPARISON TO SIMILARLY TREATED WT MICE. IN ADDITION, EARLY AFTER OVA IMMUNIZATION, MORE CD4(+) T CELLS FROM B6.CD4.EZH2-KO MICE HAD A CD44(LO)/CD62L(LO) PHENOTYPE, WHICH SUGGESTS ARRESTED OR DELAYED ACTIVATION, THAN CD4(+) T CELLS FROM OVALBUMIN-IMMUNIZED B6.WT MICE. CONCLUSION: EZH2 GENE DELETION OR PHARMACOLOGICAL EZH2 INHIBITION SUPPRESSES AUTOANTIBODY PRODUCTION AND GC FORMATION IN BM12 LUPUS-LIKE CGVHD AND DECREASES AFFINITY MATURATION AND ISOTYPE SWITCHING IN RESPONSE TO IMMUNIZATION WITH A T CELL-DEPENDENT ANTIGEN. EZH2 INHIBITION MAY BE USEFUL FOR THE TREATMENT OF LUPUS AND OTHER AUTOIMMUNE DISORDERS. 2020 7 897 28 CHRONIC EXERCISE TRAINING ACTIVATES HISTONE TURNOVER IN MOUSE SKELETAL MUSCLE FIBERS. EPIGENETIC REGULATION OF SKELETAL MUSCLE ADAPTATION TO EXERCISE IS A RECENT TOPIC FOR WHICH THERE IS LIMITED INFORMATION. THIS STUDY INVESTIGATED WHETHER EXERCISE TRAINING ACTIVATES HISTONE TURNOVER IN THE SKELETAL MUSCLE FIBERS OF MICE. EXPERIMENTS USING A TETRACYCLINE-INDUCIBLE H2B-GFP EXPRESSION MODEL DEMONSTRATED THAT 4 WEEKS OF RUNNING TRAINING, BUT NOT 2 WEEKS OF TRAINING, SIGNIFICANTLY PROMOTED THE INCORPORATION OF H2B-GFP INTO NUCLEOSOMES AND THE DISSOCIATION OF HISTONE H3.3 AT BOTH TRANSCRIPTIONALLY UPREGULATED AND NONRESPONSIVE LOCI. MUSCLE-SPECIFIC PGC-1ALPHA-B-OVEREXPRESSING MICE CROSSED WITH H2B-GFP MICE SHOWED A SLIGHT INCREASE IN H2B-GFP INCORPORATION AT TRANSCRIPTIONALLY ACTIVE LOCI, BUT NOT IN THE DISSOCIATION OF H3.3 FROM NUCLEOSOMES. GENE EXPRESSION RESPONSES TO A SINGLE BOUT OF RUNNING WERE SIGNIFICANTLY ENHANCED IN 4-WEEK TRAINED MICE WHEN COMPARED WITH THOSE IN 2-WEEK TRAINED MICE. THE MOST DRASTIC INCREASE IN THE GENE RESPONSE WAS FOUND IN THE EXPRESSION OF HSPA1A AND HSPA1B, IN WHICH THE MAGNITUDE OF UPREGULATION IN RESPONSE TO RUNNING WAS SIGNIFICANTLY ENHANCED FROM 8-FOLD IN 2 WEEK TRAINED MICE TO 97- AND 121-FOLD IN 4 WEEK TRAINED MICE, RESPECTIVELY. IT WAS ALSO FOUND THAT THE HSP70 LEVEL INCREASED DURING THE TRAINING PERIOD. IN A MYONUCLEAR IMMUNOHISTOCHEMICAL ANALYSIS OF CHROMATIN REMODELERS, WE FURTHER FOUND THAT THE LEVEL OF SPT16, AN H2A-H2B-SPECIFIC CHAPERONE, WAS UPREGULATED AFTER RUNNING TRAINING. THESE RESULTS REVEALED THAT 4 WEEKS OF RUNNING TRAINING ACTIVATED HISTONE TURNOVER IN SKELETAL MUSCLE FIBERS. THEY ALSO SUGGESTED THAT HISTONE TURNOVER LED TO LOOSENING OF THE NUCLEOSOMES AND ENHANCED GENE RESPONSES TO EXERCISE. 2021 8 4057 27 MAPPING THE LINEAGE RELATIONSHIP BETWEEN CXCR5(+) AND CXCR5(-) CD4(+) T CELLS IN HIV-INFECTED HUMAN LYMPH NODES. CXCR5 IS A KEY MARKER OF FOLLICULAR HELPER T (T(FH)) CELLS. USING PRIMARY LYMPH NODES (LNS) FROM HIV-INFECTED PATIENTS, WE IDENTIFIED A POPULATION OF CXCR5(-) CD4(+) T CELLS WITH T(FH)-CELL-LIKE FEATURES. THIS CXCR5(-) SUBSET BECOMES EXPANDED IN SEVERE HIV INFECTION AND IS CHARACTERIZED BY THE UPREGULATION OF ACTIVATION MARKERS AND HIGH PD-1 AND ICOS SURFACE EXPRESSION. INTEGRATED ANALYSES ON THE PHENOTYPIC HETEROGENEITY, FUNCTIONAL CAPACITY, T CELL RECEPTOR (TCR) REPERTOIRE, TRANSCRIPTIONAL PROFILE, AND EPIGENETIC STATE OF CXCR5(-)PD-1(+)ICOS(+) T CELLS REVEALED A SHARED CLONAL RELATIONSHIP WITH T(FH) CELLS. CXCR5(-)PD-1(+)ICOS(+) T CELLS RETAINED A POISED STATE FOR CXCR5 EXPRESSION AND EXHIBITED A MIGRATORY TRANSCRIPTIONAL PROGRAM. TCR SEQUENCE OVERLAP REVEALED A CONTRIBUTION OF LN-DERIVED CXCR5(-)PD-1(+)ICOS(+) T CELLS TO CIRCULATING CXCR5(-) CD4(+) T CELLS WITH B CELL HELP FUNCTION. THESE DATA LINK LN PATHOLOGY TO CIRCULATING T CELLS AND EXPAND THE CURRENT UNDERSTANDING ON THE DIVERSITY OF T CELLS THAT REGULATE B CELL RESPONSES DURING CHRONIC INFLAMMATION. 2019 9 1837 25 EFFECTS OF PALMITATE ON GENOME-WIDE MRNA EXPRESSION AND DNA METHYLATION PATTERNS IN HUMAN PANCREATIC ISLETS. BACKGROUND: CIRCULATING FREE FATTY ACIDS ARE OFTEN ELEVATED IN PATIENTS WITH TYPE 2 DIABETES (T2D) AND OBESE INDIVIDUALS. CHRONIC EXPOSURE TO HIGH LEVELS OF SATURATED FATTY ACIDS HAS DETRIMENTAL EFFECTS ON ISLET FUNCTION AND INSULIN SECRETION. ALTERED GENE EXPRESSION AND EPIGENETICS MAY CONTRIBUTE TO T2D AND OBESITY. HOWEVER, THERE IS LIMITED INFORMATION ON WHETHER FATTY ACIDS ALTER THE GENOME-WIDE TRANSCRIPTOME PROFILE IN CONJUNCTION WITH DNA METHYLATION PATTERNS IN HUMAN PANCREATIC ISLETS. TO DISSECT THE MOLECULAR MECHANISMS LINKING LIPOTOXICITY TO IMPAIRED INSULIN SECRETION, WE INVESTIGATED THE EFFECTS OF A 48 H PALMITATE TREATMENT IN VITRO ON GENOME-WIDE MRNA EXPRESSION AND DNA METHYLATION PATTERNS IN HUMAN PANCREATIC ISLETS. METHODS: GENOME-WIDE MRNA EXPRESSION WAS ANALYZED USING AFFYMETRIX GENECHIP((R)) HUMAN GENE 1.0 ST WHOLE TRANSCRIPT-BASED ARRAY (N = 13) AND GENOME-WIDE DNA METHYLATION WAS ANALYZED USING INFINIUM HUMANMETHYLATION450K BEADCHIP (N = 13) IN HUMAN PANCREATIC ISLETS EXPOSED TO PALMITATE OR CONTROL MEDIA FOR 48 H. A NON-PARAMETRIC PAIRED WILCOXON STATISTICAL TEST WAS USED TO ANALYZE MRNA EXPRESSION. APOPTOSIS WAS MEASURED USING APO-ONE((R)) HOMOGENEOUS CASPASE-3/7 ASSAY (N = 4). RESULTS: WHILE GLUCOSE-STIMULATED INSULIN SECRETION WAS DECREASED, THERE WAS NO SIGNIFICANT EFFECT ON APOPTOSIS IN HUMAN ISLETS EXPOSED TO PALMITATE. WE IDENTIFIED 1,860 DIFFERENTIALLY EXPRESSED GENES IN PALMITATE-TREATED HUMAN ISLETS. THESE INCLUDE CANDIDATE GENES FOR T2D, SUCH AS TCF7L2, GLIS3, HNF1B AND SLC30A8. ADDITIONALLY, GENES IN GLYCOLYSIS/GLUCONEOGENESIS, PYRUVATE METABOLISM, FATTY ACID METABOLISM, GLUTATHIONE METABOLISM AND ONE CARBON POOL BY FOLATE WERE DIFFERENTIALLY EXPRESSED IN PALMITATE-TREATED HUMAN ISLETS. PALMITATE TREATMENT ALTERED THE GLOBAL DNA METHYLATION LEVEL AND DNA METHYLATION LEVELS OF CPG ISLAND SHELVES AND SHORES, 5'UTR, 3'UTR AND GENE BODY REGIONS IN HUMAN ISLETS. MOREOVER, 290 GENES WITH DIFFERENTIAL EXPRESSION HAD A CORRESPONDING CHANGE IN DNA METHYLATION, FOR EXAMPLE, TCF7L2 AND GLIS3. IMPORTANTLY, OUT OF THE GENES DIFFERENTIALLY EXPRESSED DUE TO PALMITATE TREATMENT IN HUMAN ISLETS, 67 WERE ALSO ASSOCIATED WITH BMI AND 37 WERE DIFFERENTIALLY EXPRESSED IN ISLETS FROM T2D PATIENTS. CONCLUSION: OUR STUDY DEMONSTRATES THAT PALMITATE TREATMENT OF HUMAN PANCREATIC ISLETS GIVES RISE TO EPIGENETIC MODIFICATIONS THAT TOGETHER WITH ALTERED GENE EXPRESSION MAY CONTRIBUTE TO IMPAIRED INSULIN SECRETION AND T2D. 2014 10 4210 21 METFORMIN AND VITAMIN D MODULATE INFLAMMATION AND AUTOPHAGY DURING ADIPOSE-DERIVED STEM CELL DIFFERENTIATION. ADIPOSE-DERIVED STEM CELLS (ADSCS) CAME OUT FROM THE REGENERATIVE MEDICINE LANDSCAPE FOR THEIR ABILITY TO DIFFERENTIATE INTO SEVERAL PHENOTYPES, CONTRIBUTING TO TISSUE REGENERATION BOTH IN VITRO AND IN VIVO. DYSREGULATION IN STEM CELL RECRUITMENT AND DIFFERENTIATION DURING ADIPOGENESIS IS LINKED TO A CHRONIC LOW-GRADE INFLAMMATION AND MACROPHAGE INFILTRATION INSIDE THE ADIPOSE TISSUE, INSULIN RESISTANCE, CARDIOVASCULAR DISEASE AND OBESITY. IN THE PRESENT PAPER WE AIMED TO EVALUATE THE ROLE OF METFORMIN AND VITAMIN D, ALONE OR IN COMBINATION, IN MODULATING INFLAMMATION AND AUTOPHAGY IN ADSCS DURING ADIPOGENIC COMMITMENT. ADSCS WERE CULTURED FOR 21 DAYS IN THE PRESENCE OF A SPECIFIC ADIPOGENIC DIFFERENTIATION MEDIUM, TOGETHER WITH METFORMIN, OR VITAMIN D, OR BOTH. WE THEN ANALYZED THE EXPRESSION OF FOXO1 AND HEAT SHOCK PROTEINS (HSP) AND THE SECRETION OF PROINFLAMMATORY CYTOKINES IL-6 AND TNF-ALPHA BY ELISA. AUTOPHAGY WAS ALSO ASSESSED BY SPECIFIC WESTERN BLOT ANALYSIS OF ATG12, LC3B I, AND LC3B II EXPRESSION. OUR RESULTS SHOWED THE ABILITY OF THE CONDITIONED MEDIA TO MODULATE ADIPOGENIC DIFFERENTIATION, FINELY TUNING THE INFLAMMATORY RESPONSE AND AUTOPHAGY. WE OBSERVED A MODULATION IN HSP MRNA LEVELS, AND A SIGNIFICANT DOWNREGULATION IN CYTOKINE SECRETION. TAKEN TOGETHER, OUR FINDINGS SUGGEST THE POSSIBLE APPLICATION OF THESE MOLECULES IN CLINICAL PRACTICE TO COUNTERACT UNCONTROLLED LIPOGENESIS AND PREVENT OBESITY AND OBESITY-RELATED METABOLIC DISORDERS. 2021 11 891 29 CHRONIC EFFECTS OF CLOFIBRIC ACID IN ZEBRAFISH (DANIO RERIO): A MULTIGENERATIONAL STUDY. CLOFIBRIC ACID (CA) IS AN ACTIVE METABOLITE OF THE BLOOD LIPID LOWERING AGENT CLOFIBRATE, A PHARMACEUTICAL DESIGNED TO WORK AS AGONIST OF PEROXISOME PROLIFERATOR-ACTIVATED RECEPTOR ALPHA (PPARA). IT IS THE MOST COMMONLY REPORTED FIBRATE IN AQUATIC ENVIRONMENTS WITH LOW DEGRADATION RATE AND POTENTIAL ENVIRONMENTAL PERSISTENCE. PREVIOUS FISH EXPOSURES SHOWED THAT CA MAY IMPACT SPERMATOGENESIS, GROWTH AND THE EXPRESSION OF FAT BINDING PROTEIN GENES. HOWEVER, THERE ARE LIMITED DATA ON THE EFFECTS OF CHRONIC MULTIGENERATIONAL CA EXPOSURES. HERE, WE ASSESSED CHRONIC MULTIGENERATIONAL EFFECTS OF CA EXPOSURE USING ZEBRAFISH (DANIO RERIO) AS A TELEOST MODEL. ZEBRAFISH WERE EXPOSED THROUGH THE DIET TO CA (1 AND 10MG/G) DURING THEIR WHOLE LIFETIME. GROWTH, REPRODUCTION-RELATED PARAMETERS AND EMBRYONIC DEVELOPMENT WERE ASSESSED IN THE EXPOSED FISH (F1 GENERATION) AND THEIR OFFSPRING (F2 GENERATION), TOGETHER WITH MUSCLE TRIGLYCERIDE CONTENT AND GONAD HISTOLOGY. IN ORDER TO STUDY THE POTENTIAL UNDERLYING MECHANISMS, THE TRANSCRIPTION LEVELS OF GENES CODING FOR ENZYMES INVOLVED IN LIPID METABOLISM PATHWAYS WERE DETERMINED. THE RESULTS SHOW THAT CHRONIC LIFE-CYCLE EXPOSURE TO CA INDUCED A SIGNIFICANT REDUCTION IN GROWTH OF F1 GENERATION AND LOWERED TRIGLYCERIDE MUSCLE CONTENT (10MG/G GROUP). ALSO, AN IMPACT IN MALE GONAD DEVELOPMENT WAS OBSERVED TOGETHER WITH A DECREASE IN THE FECUNDITY (10MG/G GROUP) AND HIGHER FREQUENCY OF EMBRYO ABNORMALITIES IN THE OFFSPRING OF FISH EXPOSED TO THE LOWEST CA DOSE. THE PROFILE OF THE TARGET GENES WAS SEX- AND TISSUE-DEPENDENT. IN F1 AN UP-REGULATION OF MALE HEPATIC PPARAA, PPARB AND ACOX TRANSCRIPT LEVELS WAS OBSERVED, SUGGESTING AN ACTIVATION OF THE FATTY ACID METABOLISM (PROVIDED THAT TRANSCRIPT LEVEL CHANGE INDICATES ALSO A PROTEIN LEVEL CHANGE). INTERESTINGLY, THE F2 GENERATION, RAISED WITH CONTROL DIET, DISPLAYED A RESPONSE PATTERN DIFFERENT FROM THAT OBSERVED IN F1, SHOWING AN INCREASE IN WEIGHT IN THE DESCENDANTS OF CA EXPOSED FISH, IN COMPARISON WITH CONTROL ANIMALS, WHICH POINTS TO A MULTIGENERATIONAL EFFECT. 2015 12 4924 19 PARENTAL HYPOXIC EXPOSURE CONFERS OFFSPRING HYPOXIA RESISTANCE IN ZEBRAFISH (DANIO RERIO). PARENTAL INFLUENCES ARE A POTENTIALLY IMPORTANT COMPONENT OF TRANSGENERATIONAL TRANSFER OF PHENOTYPE IN VERTEBRATES. THIS STUDY EXAMINED HOW CHRONIC HYPOXIC EXPOSURE ON ADULT ZEBRAFISH (DANIO RERIO) AFFECTED THE PHENOTYPE OF THEIR OFFSPRING. SEPARATE ADULT POPULATIONS WERE EXPOSED TO HYPOXIA (13.1 KPA O(2)) OR NORMOXIA (21.1 KPA O(2)) FOR PERIODS RANGING FROM 1 TO 12 WEEKS. ADULTS WERE THEN RETURNED TO NORMOXIA AND BRED WITHIN EXPERIMENTAL GROUPS. ADULT FECUNDITY AND EGG CHARACTERISTICS (VOLUME OF EGG, YOLK AND PERIVITELLINE FLUID) WERE ASSESSED. SUBSEQUENTLY, LARVAL BODY LENGTH, TIME TO LOSS OF EQUILIBRIUM IN SEVERE HYPOXIA (~4 KPA O(2)), AND CRITICAL THERMAL MINIMA (CT(MIN)) AND MAXIMA (CT(MAX)) WERE MEASURED AT 6, 9, 12, 15, 18, 21 AND 60 DAYS POST-FERTILIZATION (D.P.F.). ADULT FECUNDITY WAS DEPRESSED BY HYPOXIC EXPOSURE. EGG COMPONENT VOLUMES WERE ALSO DEPRESSED IN ADULTS EXPOSED TO 1-2 WEEKS OF HYPOXIA, BUT RETURNED TO CONTROL LEVELS FOLLOWING LONGER HYPOXIC EXPOSURE. ADULT HYPOXIC EXPOSURES OF >1 WEEK RESULTED IN LONGER BODY LENGTHS IN THEIR LARVAL OFFSPRING. TIME TO LOSS OF EQUILIBRIUM IN SEVERE HYPOXIA (I.E. HYPOXIC RESISTANCE) IN CONTROL LARVAE DECREASED FROM 6 TO 12 D.P.F., REMAINING CONSTANT THEREAFTER. NOTABLY, HYPOXIC RESISTANCE FROM 6 TO 18 D.P.F. WAS ~15% LOWER IN LARVAE WHOSE PARENTS WERE EXPOSED TO JUST 1 WEEK OF CHRONIC HYPOXIA, BUT RESISTANCE WAS SIGNIFICANTLY INCREASED BY ~24-30% IN 6-18 D.P.F. LARVAE FROM ADULTS EXPOSED TO 2, 3 OR 4 WEEKS OF HYPOXIA. CT(MIN) (~10-12 DEGREES C) AND CT(MAX) (~39.5 DEGREES C) WERE UNCHANGED BY PARENTAL HYPOXIC EXPOSURE. THIS STUDY DEMONSTRATES THAT PARENTAL HYPOXIC EXPOSURE IN ADULT ZEBRAFISH HAS PROFOUND EPIGENETIC EFFECTS ON THE MORPHOLOGICAL AND PHYSIOLOGICAL PHENOTYPE OF THEIR OFFSPRING. 2012 13 4253 23 METHYLOME OF HUMAN SKELETAL MUSCLE AFTER ACUTE & CHRONIC RESISTANCE EXERCISE TRAINING, DETRAINING & RETRAINING. DNA METHYLATION IS AN IMPORTANT EPIGENETIC MODIFICATION THAT CAN REGULATE GENE EXPRESSION FOLLOWING ENVIRONMENTAL ENCOUNTERS WITHOUT CHANGES TO THE GENETIC CODE. USING INFINIUM METHYLATIONEPIC BEADCHIP ARRAYS (850,000 CPG SITES) WE ANALYSED FOR THE FIRST TIME, DNA ISOLATED FROM UNTRAINED HUMAN SKELETAL MUSCLE BIOPSIES (VASTUS LATERALIS) AT BASELINE (REST) AND IMMEDIATELY FOLLOWING AN ACUTE (SINGLE) BOUT OF RESISTANCE EXERCISE. IN THE SAME PARTICIPANTS, WE ALSO ANALYSED THE METHYLOME FOLLOWING A PERIOD OF MUSCLE GROWTH (HYPERTROPHY) EVOKED VIA CHRONIC (REPEATED BOUTS-3 SESSIONS/WK) RESISTANCE EXERCISE (RE) (TRAINING) OVER 7-WEEKS, FOLLOWED BY COMPLETE EXERCISE CESSATION FOR 7-WEEKS RETURNING MUSCLE BACK TO BASELINE LEVELS (DETRAINING), AND FINALLY FOLLOWED BY A SUBSEQUENT 7-WEEK PERIOD OF RE-INDUCED HYPERTROPHY (RETRAINING). THESE VALUABLE METHYLOME DATA SETS DESCRIBED IN THE PRESENT MANUSCRIPT AND DEPOSITED IN AN OPEN-ACCESS REPOSITORY CAN NOW BE SHARED AND RE-USED TO ENABLE THE IDENTIFICATION OF EPIGENETICALLY REGULATED GENES/NETWORKS THAT ARE MODIFIED AFTER ACUTE ANABOLIC STIMULI AND HYPERTROPHY, AND FURTHER INVESTIGATE THE PHENOMENON OF EPIGENETIC MEMORY IN SKELETAL MUSCLE. 2018 14 3339 31 HISTONE DEACETYLASE ISOFORMS DIFFERENTIALLY MODULATE INFLAMMATORY AND AUTOANTIBODY RESPONSES IN A MOUSE MODEL OF MYASTHENIA GRAVIS. MYASTHENIA GRAVIS (MG) IS AN AUTOIMMUNE DISEASE CHARACTERIZED BY CHRONIC MUSCLE FATIGUE AND WEAKNESS CAUSED BY AUTOANTIBODIES AND COMPLEMENT-MEDIATED DAMAGE AT NEUROMUSCULAR JUNCTIONS. HISTONE DEACETYLASES (HDACS) ARE CRUCIAL EPIGENETIC REGULATORS OF PROINFLAMMATORY GENE EXPRESSION; HOWEVER, IT IS UNCLEAR WHETHER HDACS MODULATE CHRONIC INFLAMMATION OR AUTOANTIBODY PRODUCTION ASSOCIATED WITH MG PATHOGENESIS. WE EXAMINED EXPRESSION PROFILES AND SERUM LEVELS OF KEY INFLAMMATORY CYTOKINES (IL-6 AND IL-21) AND ACETYLCHOLINE RECEPTOR (ACHR)-SPECIFIC AUTOANTIBODIES FOLLOWING PHARMACOLOGICAL INHIBITION OF KEY HDAC ISOFORMS IN A MOUSE MODEL OF MG. WE FOUND THAT HDAC INHIBITION SIGNIFICANTLY REDUCED THE PRODUCTION OF IL-6, BUT NOT IL-21, IN ACHR-STIMULATED PBMCS AND SPLENOCYTES (N = 5 PER GROUP). TRICHOSTATIN (PAN-HDAC INHIBITOR) TREATMENT OF MG-PBMCS (N = 2) ALSO EXHIBITED REDUCED PRODUCTION OF INDUCED IL-6. ALTHOUGH HDAC1 INHIBITION LOWERED IL-6 LEVELS THE MOST, HDAC2 INHIBITION DEPLETED INTRACELLULAR IL-6 AND MARKEDLY REDUCED SERUM ANTI-ACHR IGG2B IN EAMG MICE. THE TRANSCRIPTOMIC PROFILING AND PATHWAY MAPPING ALSO REVEALED THAT AUTOIMMUNITY-LINKED, MAJOR CELL SIGNALING PATHWAYS WERE DIFFERENTIALLY ALTERED BY HDAC1/2 INHIBITION. HDAC INHIBITION-MEDIATED REDUCTION IN IL-6 AND AUTOANTIBODY LEVELS ALSO CORRELATED WITH MILDER DISEASE AND PRESERVATION OF MUSCLE ACHR IN THE TREATED MICE. OVERALL, OUR FINDINGS REVEALED ISOFORM-SPECIFIC FUNCTIONAL VARIANCE OF HDACS IN REDUCING INFLAMMATION AND IDENTIFIED HDAC-REGULATED MANY GENES UNDERLYING SPECIFIC INFLAMMATORY AND AUTOANTIBODY PATHWAYS IN EAMG. THUS, THE STUDY PROVIDES A RATIONALE FOR FURTHER RESEARCH TO EVALUATE THE HDACS OR THEIR GENE TARGETS AS A POTENTIAL ADJUNCT TREATMENT FOR MG. 2021 15 3281 22 HETEROGENEOUS TFH CELL POPULATIONS THAT DEVELOP DURING ENTERIC HELMINTH INFECTION PREDICT THE QUALITY OF TYPE 2 PROTECTIVE RESPONSE. T FOLLICULAR HELPER (TFH) CELLS ARE AN IMPORTANT COMPONENT OF GERMINAL CENTER (GC)-MEDIATED HUMORAL IMMUNITY. YET, HOW A CHRONIC TYPE 1 VERSUS PROTECTIVE TYPE 2 HELMINTH INFECTION MODULATES TFH-GC RESPONSES REMAINS POORLY UNDERSTOOD. HERE, WE EMPLOY THE HELMINTH TRICHURIS MURIS MODEL AND DEMONSTRATE THAT TFH CELL PHENOTYPES AND GC ARE DIFFERENTIALLY REGULATED IN ACUTE VERSUS CHRONIC INFECTION. THE LATTER FAILED TO INDUCE TFH-GC B CELL RESPONSES, WITH TFH CELLS EXPRESSING TAU-BET AND INTERFERON-GAMMA. IN CONTRAST, INTERLEUKIN-4-PRODUCING TFH CELLS DOMINATE RESPONSES TO AN ACUTE, RESOLVING INFECTION. HEIGHTENED EXPRESSION AND INCREASED CHROMATIN ACCESSIBILITY OF T HELPER (TH)1- AND TH2 CELL-ASSOCIATED GENES ARE OBSERVED IN CHRONIC AND ACUTE INDUCED TFH CELLS, RESPECTIVELY. BLOCKADE OF THE TH1 CELL RESPONSE BY T-CELL-INTRINSIC T-BET DELETION PROMOTED TFH CELL EXPANSION DURING CHRONIC INFECTION, POINTING TO A CORRELATION BETWEEN A ROBUST TFH CELL RESPONSE AND PROTECTIVE IMMUNITY TO PARASITES. FINALLY, BLOCKADE OF TFH-GC INTERACTIONS IMPAIRED TYPE 2 IMMUNITY, REVEALING THE CRITICAL PROTECTIVE ROLE OF GC-DEPENDENT TH2-LIKE TFH CELL RESPONSES DURING ACUTE INFECTION. COLLECTIVELY, THESE RESULTS PROVIDE NEW INSIGHTS INTO THE PROTECTIVE ROLES OF TFH-GC RESPONSES AND IDENTIFY DISTINCT TRANSCRIPTIONAL AND EPIGENETIC FEATURES OF TFH CELLS THAT EMERGE DURING RESOLVING OR CHRONIC T. MURIS INFECTION. 2023 16 6471 28 TNF-ALPHA REGULATES DIABETIC MACROPHAGE FUNCTION THROUGH THE HISTONE ACETYLTRANSFERASE MOF. A CRITICAL COMPONENT OF WOUND HEALING IS THE TRANSITION FROM THE INFLAMMATORY PHASE TO THE PROLIFERATION PHASE TO INITIATE HEALING AND REMODELING OF THE WOUND. MACROPHAGES ARE CRITICAL FOR THE INITIATION AND RESOLUTION OF THE INFLAMMATORY PHASE DURING WOUND REPAIR. IN DIABETES, MACROPHAGES DISPLAY A SUSTAINED INFLAMMATORY PHENOTYPE IN LATE WOUND HEALING CHARACTERIZED BY ELEVATED PRODUCTION OF INFLAMMATORY CYTOKINES, SUCH AS TNF-ALPHA. PREVIOUS STUDIES HAVE SHOWN THAT AN ALTERED EPIGENETIC PROGRAM DIRECTS DIABETIC MACROPHAGES TOWARD A PROINFLAMMATORY PHENOTYPE, CONTRIBUTING TO A SUSTAINED INFLAMMATORY PHASE. MALES ABSENT ON THE FIRST (MOF) IS A HISTONE ACETYLTRANSFERASE (HAT) THAT HAS BEEN SHOWN BE A COACTIVATOR OF TNF-ALPHA SIGNALING AND PROMOTE NF-KAPPAB-MEDIATED GENE TRANSCRIPTION IN PROSTATE CANCER CELL LINES. BASED ON MOF'S ROLE IN TNF-ALPHA/NF-KAPPAB-MEDIATED GENE EXPRESSION, WE HYPOTHESIZED THAT MOF INFLUENCES MACROPHAGE-MEDIATED INFLAMMATION DURING WOUND REPAIR. WE USED MYELOID-SPECIFIC MOF-KNOCKOUT (LYZ2CRE MOFFL/FL) AND DIET-INDUCED OBESE (DIO) MICE TO DETERMINE THE FUNCTION OF MOF IN DIABETIC WOUND HEALING. MOF-DEFICIENT MICE EXHIBITED REDUCED INFLAMMATORY CYTOKINE GENE EXPRESSION. FURTHERMORE, WE FOUND THAT WOUND MACROPHAGES FROM DIO MICE HAD ELEVATED MOF LEVELS AND HIGHER LEVELS OF ACETYLATED HISTONE H4K16, MOF'S PRIMARY SUBSTRATE OF HAT ACTIVITY, ON THE PROMOTERS OF INFLAMMATORY GENES. WE FURTHER IDENTIFIED THAT MOF EXPRESSION COULD BE STIMULATED BY TNF-ALPHA AND THAT TREATMENT WITH ETANERCEPT, AN FDA-APPROVED TNF-ALPHA INHIBITOR, REDUCED MOF LEVELS AND IMPROVED WOUND HEALING IN DIO MICE. THIS REPORT IS THE FIRST TO OUR KNOWLEDGE TO DEFINE AN IMPORTANT ROLE FOR MOF IN REGULATING MACROPHAGE-MEDIATED INFLAMMATION IN WOUND REPAIR AND IDENTIFIES TNF-ALPHA INHIBITION AS A POTENTIAL THERAPY FOR THE TREATMENT OF CHRONIC INFLAMMATION IN DIABETIC WOUNDS. 2020 17 169 31 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 18 545 22 ATTENUATED EPIGENETIC SUPPRESSION OF MUSCLE STEM CELL NECROPTOSIS IS REQUIRED FOR EFFICIENT REGENERATION OF DYSTROPHIC MUSCLES. SOMATIC STEM CELLS EXPAND MASSIVELY DURING TISSUE REGENERATION, WHICH MIGHT REQUIRE CONTROL OF CELL FITNESS, ALLOWING ELIMINATION OF NON-COMPETITIVE, POTENTIALLY HARMFUL CELLS. HOW OR IF SUCH CELLS ARE REMOVED TO RESTORE ORGAN FUNCTION IS NOT FULLY UNDERSTOOD. HERE, WE SHOW THAT A SUBSTANTIAL FRACTION OF MUSCLE STEM CELLS (MUSCS) UNDERGO NECROPTOSIS BECAUSE OF EPIGENETIC REWIRING DURING CHRONIC SKELETAL MUSCLE REGENERATION, WHICH IS REQUIRED FOR EFFICIENT REGENERATION OF DYSTROPHIC MUSCLES. INHIBITION OF NECROPTOSIS STRONGLY ENHANCES SUPPRESSION OF MUSC EXPANSION IN A NON-CELL-AUTONOMOUS MANNER. PREVENTION OF NECROPTOSIS IN MUSCS OF HEALTHY MUSCLES IS MEDIATED BY THE CHROMATIN REMODELER CHD4, WHICH DIRECTLY REPRESSES THE NECROPTOTIC EFFECTOR RIPK3, WHILE CHD4-DEPENDENT RIPK3 REPRESSION IS DRAMATICALLY ATTENUATED IN DYSTROPHIC MUSCLES. LOSS OF RIPK3 REPRESSION BY INACTIVATION OF CHD4 CAUSES MASSIVE NECROPTOSIS OF MUSCS, ABOLISHING REGENERATION. OUR STUDY DEMONSTRATES HOW PROGRAMMED CELL DEATH IN MUSCS IS TIGHTLY CONTROLLED TO ACHIEVE OPTIMAL TISSUE REGENERATION. 2020 19 3615 27 IN VITRO FOLATE DEFICIENCY INDUCES DEOXYNUCLEOTIDE POOL IMBALANCE, APOPTOSIS, AND MUTAGENESIS IN CHINESE HAMSTER OVARY CELLS. THE GENETIC AND EPIGENETIC EFFECTS OF NUTRITIONAL FOLATE DEFICIENCY WERE STUDIED IN TWO CHINESE HAMSTER OVARY (CHO) CELL LINES. THE CHO-AA8 CELL LINE (HEMIZYGOUS AT THE APRT LOCUS) AND CHO-UV5 (DNA REPAIR-DEFICIENT MUTANT OF AA8) WERE CULTURED IN HAM'S F-12 MEDIUM OR IN CUSTOM-PREPARED HAM'S F-12 MEDIUM LACKING FOLIC ACID, THYMIDINE, AND HYPOXANTHINE. CELLS CULTURED ACUTELY IN THE FOLATE DEFICIENT MEDIUM EXHIBITED INITIAL GROWTH ARREST, FOLLOWED BY MASSIVE CELL DEATH AND DNA FRAGMENTATION INTO NUCLEOSOMAL MULTIMERS CHARACTERISTIC OF APOPTOSIS. ALTHOUGH PROLONGED CULTURE IN THE FOLATE DEFICIENT MEDIUM WAS CYTOSTATIC AND LETHAL TO THE MAJORITY CELLS, MINOR SUBPOPULATIONS IN BOTH CELL LINES FAILED TO INITIATE CELL DEATH, EXHIBITED PHENOTYPIC ABNORMALITIES, AND ADAPTED A SELECTIVE GROWTH ADVANTAGE UNDER MARGINAL FOLATE CONDITIONS. THESE "RESISTANT" CLONES EXHIBITED MAJOR ALTERATIONS IN DEOXYNUCLEOTIDE POOLS ASSOCIATED WITH AN INCREASE IN MUTANT FREQUENCY AT THE APRT LOCUS AS DETECTED BY RESISTANCE TO CYTOTOXICITY IN 8-AZAADENOSINE. THE MUTATION FREQUENCY IN THE DNA REPAIR-DEFICIENT CHO-UV5 CELLS WAS APPROXIMATELY 100-FOLD GREATER THAN THAT IN THE PARENTAL AA8 CLONES, UNDERSCORING THE IMPORTANCE OF DNA REPAIR UNDER CONDITIONS OF FOLATE DEFICIENCY AND NUCLEOTIDE POOL IMBALANCE. THE ENHANCED MUTATION FREQUENCY IN THE DNA REPAIR-COMPETENT FOLATE-DEFICIENT CHO-AA8 CELLS SUGGESTS THAT DNA REPAIR ACTIVITY IS LESS EFFECTIVE UNDER FOLATE-DEFICIENT CONDITIONS. THESE RESULTS ADD TO THE ACCUMULATING CLINICAL AND EXPERIMENTAL EVIDENCE RELATING CHRONIC FOLATE DEFICIENCY TO GENOMIC INSTABILITY AND CARCINOGENESIS. 1994 20 4042 29 MACROPHAGES ACQUIRE A TNF-DEPENDENT INFLAMMATORY MEMORY IN ALLERGIC ASTHMA. BACKGROUND: INFECTIOUS AGENTS CAN REPROGRAM OR "TRAIN" MACROPHAGES AND THEIR PROGENITORS TO RESPOND MORE READILY TO SUBSEQUENT INSULTS. HOWEVER, WHETHER SUCH AN INFLAMMATORY MEMORY EXISTS IN TYPE 2 INFLAMMATORY CONDITIONS SUCH AS ALLERGIC ASTHMA WAS NOT KNOWN. OBJECTIVE: WE SOUGHT TO DECIPHER MACROPHAGE-TRAINED IMMUNITY IN ALLERGIC ASTHMA. METHODS: WE USED A COMBINATION OF CLINICAL SAMPLING OF HOUSE DUST MITE (HDM)-ALLERGIC PATIENTS, HDM-INDUCED ALLERGIC AIRWAY INFLAMMATION IN MICE, AND AN IN VITRO TRAINING SETUP TO ANALYZE PERSISTENT CHANGES IN MACROPHAGE EICOSANOID, CYTOKINE, AND CHEMOKINE PRODUCTION AS WELL AS THE UNDERLYING METABOLIC AND EPIGENETIC MECHANISMS. TRANSCRIPTIONAL AND METABOLIC PROFILES OF PATIENT-DERIVED AND IN VITRO TRAINED MACROPHAGES WERE ASSESSED BY RNA SEQUENCING OR METABOLIC FLUX ANALYSIS AND LIQUID CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY ANALYSIS, RESPECTIVELY. RESULTS: WE FOUND THAT MACROPHAGES DIFFERENTIATED FROM BONE MARROW OR BLOOD MONOCYTE PROGENITORS OF HDM-ALLERGIC MICE OR ASTHMA PATIENTS SHOW INFLAMMATORY TRANSCRIPTIONAL REPROGRAMMING AND EXCESSIVE MEDIATOR (TNF-ALPHA, CCL17, LEUKOTRIENE, PGE(2), IL-6) RESPONSES UPON STIMULATION. MACROPHAGES FROM HDM-ALLERGIC MICE INITIALLY EXHIBITED A TYPE 2 IMPRINT, WHICH SHIFTED TOWARD A CLASSICAL INFLAMMATORY TRAINING OVER TIME. HDM-INDUCED ALLERGIC AIRWAY INFLAMMATION ELICITED A METABOLICALLY ACTIVATED MACROPHAGE PHENOTYPE, PRODUCING HIGH AMOUNTS OF 2-HYDROXYGLUTARATE (2-HG). HDM-INDUCED MACROPHAGE TRAINING IN VITRO WAS MEDIATED BY A FORMYL PEPTIDE RECEPTOR 2-TNF-2-HG-PGE(2)/PGE(2) RECEPTOR 2 AXIS, RESULTING IN AN M2-LIKE MACROPHAGE PHENOTYPE WITH HIGH CCL17 PRODUCTION. TNF BLOCKADE BY ETANERCEPT OR GENETIC ABLATION OF TNF IN MYELOID CELLS PREVENTED THE INFLAMMATORY IMPRINTING OF BONE MARROW-DERIVED MACROPHAGES FROM HDM-ALLERGIC MICE. CONCLUSION: ALLERGEN-TRIGGERED INFLAMMATION DRIVES A TNF-DEPENDENT INNATE MEMORY, WHICH MAY PERPETUATE AND EXACERBATE CHRONIC TYPE 2 AIRWAY INFLAMMATION AND THUS REPRESENTS A TARGET FOR ASTHMA THERAPY. 2022