1 3424 215 HUMAN STEM CELLS ISOLATED FROM ADULT SKELETAL MUSCLE DIFFERENTIATE INTO NEURAL PHENOTYPES. MULTIPOTENT NEURAL STEM CELLS HAVE BEEN ISOLATED FROM THE ADULT [KIRSCHENBAUM B, NEDERGAARD M, PREUSS A, BARAMI K, FRASER RA, GOLDMAN SA. IN VITRO NEURONAL PRODUCTION AND DIFFERENTIATION BY PRECURSOR CELLS DERIVED FROM THE ADULT HUMAN FOREBRAIN. CEREB CORTEX 1994;4(6):576-89; LAYWELL ED, KUKEKOV VG, STEINDLER DA. MULTIPOTENT NEUROSPHERES CAN BE DERIVED FROM FOREBRAIN SUBEPENDYMAL ZONE AND SPINAL CORD OF ADULT MICE AFTER PROTRACTED POSTMORTEM INTERVALS. EXP NEUROL 1999;156:430-3; PLUCHINO S, QUATTRINI A, BRAMBILLA E, GRITTI A, SALANI G, DINA G, ET AL. INJECTION OF ADULT NEUROSPHERES INDUCES RECOVERY IN A CHRONIC MODEL OF MULTIPLE SCLEROSIS. NATURE 2003;422:688-94] AND EMBRYONIC [VESCOVI AL, PARATI EA, GRITTI A, POULIN P, FERRARIO M, WANKE E, ET AL. ISOLATION AND CLONING OF MULTIPOTENTIAL STEM CELLS FROM THE EMBRYONIC HUMAN CNS AND ESTABLISHMENT OF TRANSPLANTABLE HUMAN NEURAL STEM CELL LINES BY EPIGENETIC STIMULATION. EXP NEUROL 1999;156:71-83] CENTRAL NERVOUS SYSTEM (CNS). IN ADDITION, NEURAL CELLS CAN BE OBTAINED FROM SOURCES OTHER THAN THE CNS BY DIFFERENTIATING STEM CELLS FROM A NON-NEURAL SOURCE DOWN A NEURAL LINEAGE. THIS HAS PREVIOUSLY BEEN PERFORMED WITH PLURIPOTENT EMBRYONIC STEM CELLS AND ADULT STEM CELLS DERIVED FROM RAT BONE MARROW [WOODBURY D, SCHWARZ EJ, PROCKOP DJ, BLACK IB. ADULT RAT AND HUMAN BONE MARROW STROMAL CELLS DIFFERENTIATE INTO NEURONS. J NEUROSCI RES 2000;61:364-70; WOODBURY D, REYNOLDS K, BLACK IB. ADULT BONE MARROW STROMAL STEM CELLS EXPRESS GERMLINE, ECTODERMAL, ENDODERMAL, AND MESODERMAL GENES PRIOR TO NEUROGENESIS. J NEUROSCI 2002;69(6):908-17] AND SKELETAL MUSCLE [ROMERO-RAMOS M, VOURC'H P, YOUNG HE, LUCAS PA, WU Y, CHIVATAKARN O, ET AL. NEURONAL DIFFERENTIATION OF STEM CELLS ISOLATED FROM ADULT MUSCLE. J NEUROSCI RES 2002;69:894-907]. PREVIOUSLY, WE HAVE ISOLATED ADULT STEM CELLS FROM HUMAN SKELETAL MUSCLE WITH THE POTENTIAL TO DIFFERENTIATE INTO MESODERM, ECTODERM, AND ENDODERM. THE FOLLOWING IN VITRO EXPERIMENTS WERE DESIGNED TO DETERMINE WHETHER HUMAN ADULT STEM CELLS BEHAVED SIMILARLY TO RAT ADULT STEM CELLS WHEN BOTH WERE ISOLATED FROM SKELETAL MUSCLE BY THE SAME PROCEDURE [ROMERO-RAMOS M, VOURC'H P, YOUNG HE, LUCAS PA, WU Y, CHIVATAKARN O, ET AL. NEURONAL DIFFERENTIATION OF STEM CELLS ISOLATED FROM ADULT MUSCLE. J NEUROSCI RES 2002;69:894-907] AND SUBJECTED TO THE SAME PROTOCOLS TO INDUCE NEUROGENESIS. THE NEURAL PHENOTYPES THAT WERE CREATED THROUGH THE NEUROCOCKTAIL OR NEUROSPHERE PROTOCOL WERE ANALYZED FOR NEURAL CHARACTERISTICS THROUGH MORPHOLOGY AND IMMUNOHISTOCHEMISTRY ANTIBODY LABELING FOR PROTEINS TO NEURONS (RT-97, BETA-TUBULIN III, NF-160, NF-200, AND SYNAPSIN), OLIGODENDROCYTES (CNPASE AND RIP), AND ASTROCYTES (GFAP). A CALCIUM UPTAKE ASSAY ALSO SHOWED RESPONSE TO THE NEURONAL EXCITOTOXIC AGENT GLUTAMIC ACID. IN CONCLUSION, THE NEURAL DIFFERENTIATED STEM CELLS DERIVED FROM ADULT SKELETAL MUSCLE MAY BE A LESS INVASIVE ALTERNATIVE FOR THE TREATMENT OF CNS DISORDERS OVER CNS DERIVED NEURAL STEM CELLS. 2006 2 3835 30 IONISING RADIATION INDUCES PROMOTER DNA HYPOMETHYLATION AND PERTURBS TRANSCRIPTIONAL ACTIVITY OF GENES INVOLVED IN MORPHOGENESIS DURING GASTRULATION IN ZEBRAFISH. EMBRYONIC DEVELOPMENT IS PARTICULARLY VULNERABLE TO STRESS AND DNA DAMAGE, AS MUTATIONS CAN ACCUMULATE THROUGH CELL PROLIFERATION IN A WIDE NUMBER OF CELLS AND ORGANS. HOWEVER, THE BIOLOGICAL EFFECTS OF CHRONIC EXPOSURE TO IONISING RADIATION (IR) AT LOW AND MODERATE DOSE RATES (< 6 MGY/H) REMAIN LARGELY CONTROVERSIAL, RAISING CONCERNS FOR ENVIRONMENTAL PROTECTION. THE PRESENT STUDY FOCUSES ON THE MOLECULAR EFFECTS OF IR (0.005 TO 50 MGY/H) ON ZEBRAFISH EMBRYOS AT THE GASTRULA STAGE (6 HPF), AT BOTH THE TRANSCRIPTOMICS AND EPIGENETICS LEVELS. OUR RESULTS SHOW THAT EXPOSURE TO IR MODIFIES THE EXPRESSION OF GENES INVOLVED IN MITOCHONDRIAL ACTIVITY FROM 0.5 TO 50 MGY/H. IN ADDITION, IMPORTANT DEVELOPMENTAL PATHWAYS, NAMELY, THE NOTCH, RETINOIC ACID, BMP AND WNT SIGNALLING PATHWAYS, WERE ALTERED AT 5 AND 50 MGY/H. TRANSCRIPTIONAL CHANGES OF GENES INVOLVED IN THE MORPHOGENESIS OF THE ECTODERM AND MESODERM WERE DETECTED AT ALL DOSE RATES, BUT WERE PROMINENT FROM 0.5 TO 50 MGY/H. AT THE EPIGENETIC LEVEL, EXPOSURE TO IR INDUCED A HYPOMETHYLATION OF DNA IN THE PROMOTER OF GENES THAT COLOCALISED WITH BOTH H3K27ME3 AND H3KME4 HISTONE MARKS AND CORRELATED WITH CHANGES IN TRANSCRIPTIONAL ACTIVITY. FINALLY, PATHWAY ENRICHMENT ANALYSIS DEMONSTRATED THAT THE DNA METHYLATION CHANGES OCCURRED IN THE PROMOTER OF IMPORTANT DEVELOPMENTAL GENES, INCLUDING MORPHOGENESIS OF THE ECTODERM AND MESODERM. TOGETHER, THESE RESULTS SHOW THAT THE TRANSCRIPTIONAL PROGRAM REGULATING MORPHOGENESIS IN GASTRULATING EMBRYOS WAS MODIFIED AT DOSE RATES GREATER THAN OR EQUAL TO 0.5 MGY/H, WHICH MIGHT PREDICT POTENTIAL NEUROGENESIS AND SOMITOGENESIS DEFECTS OBSERVED AT SIMILAR DOSE RATES LATER IN DEVELOPMENT. 2020 3 2138 23 EPIGENETIC INHERITANCE OF FETAL GENES IN ALLERGIC ASTHMA. ASTHMA HAS BEEN ASSOCIATED WITH AN EXAGGERATED T-HELPER TYPE 2 (TH2) OVER TH1 RESPONSES TO ALLERGIC AND NONALLERGIC STIMULI, WHICH LEADS TO CHRONIC AIRWAY INFLAMMATION AND AIRWAY REMODELING. IN THE PRESENT ARTICLE, WE PROPOSE THAT MANY OF THE GENES INVOLVED IN IGE SYNTHESIS AND AIRWAYS (RE)MODELING IN ASTHMA ARE PERSISTENT OR REMINISCENT FETAL GENES WHICH MAY NOT BE SILENCED DURING EARLY INFANCY (OR LATE PREGNANCY). GENES OF THE EMBRYOLOGIC DIFFERENTIATION OF ECTODERMIC AND ENDODERMIC TISSUES MAY EXPLAIN SOME OF THE PATTERNS OF AIRWAY REMODELING IN ASTHMA. IN UTERO PROGRAMMING LEADS TO GENE EXPRESSION, THE PERSISTENCE OF WHICH MAY BE ASSOCIATED WITH EPIGENETIC INHERITANCE PHENOMENA INDUCED BY NONSPECIFIC ENVIRONMENTAL FACTORS. CLEAR DELINEATION OF THESE ISSUES MAY YIELD NEW INFORMATION ON THE MECHANISMS OF ASTHMA AND NEW TARGETS FOR THERAPEUTIC INTERVENTION AND PRIMARY PREVENTION. 2004 4 4529 22 MULTIGENERATIONAL GRAPHENE OXIDE INTOXICATION RESULTS IN REPRODUCTION DISORDERS AT THE MOLECULAR LEVEL OF VITELLOGENIN PROTEIN EXPRESSION IN ACHETA DOMESTICUS. THE ANTHROPOGENIC ACTIVITIES MAY LEAD TO ACCUMULATION OF GRAPHENE OXIDE (GO) POLLUTION IN THE ENVIRONMENT. ORGANISMS EXPOSED TO CHRONIC OR MULTIGENERATIONAL GO INTOXICATION CAN PRESENT REPRODUCTION DEPLETION. VITELLOGENIN (VG) HAS BEEN USED AS A PARAMETER FOR EVALUATING FEMALE FERTILITY DUE TO ITS IMPORTANCE IN EMBRYO NUTRITION. IN THIS STUDY, WE USED A PROMISING MODEL ORGANISM, ACHETA DOMESTICUS, WHICH WAS INTOXICATED WITH GO IN FOOD FOR THREE GENERATIONS. THE AIM OF THE STUDY WAS TO INVESTIGATE THE PROCESS OF VG SYNTHESIS IN CRICKETS DEPENDING ON THE EXPOSURE TIME, GO CONCENTRATION, AND AGE OF THE FEMALES. THE RESULTS REVEALED THAT CHRONIC GO INTOXICATION HAD ADVERSE EFFECTS ON THE VG EXPRESSION PATTERN. THE 1ST GENERATION OF INSECTS SHOWING LOW VG EXPRESSION WAS MOST AFFECTED. THE 2ND GENERATION OF A. DOMESTICUS PRESENTED A HIGH VG EXPRESSION. THE LAST INVESTIGATED GENERATION SEEMED TO COPE WITH STRESS CAUSED BY GO, AND THE VG EXPRESSION WAS BALANCED. WE SUGGEST THAT THE EPIGENETIC MECHANISMS MAY PLAY A ROLE IN THE INFORMATION TRANSFER TO THE NEXT GENERATIONS ON HOW TO REACT TO THE RISK FACTOR AND KEEP REPRODUCTION AT A HIGH RATE. WE SUSPECT THAT CHRONIC GO INTOXICATION CAN DISTURB THE REGULAR FORMATION OF THE VG QUATERNARY STRUCTURE, RESULTING IN CONSEQUENCES FOR DEVELOPING AN EMBRYO. 2021 5 1116 47 COMPARATIVE ANALYSIS OF NEUROECTODERMAL DIFFERENTIATION CAPACITY OF HUMAN BONE MARROW STROMAL CELLS USING VARIOUS CONVERSION PROTOCOLS. HUMAN ADULT BONE MARROW-DERIVED MESODERMAL STROMAL CELLS (HMSCS) ARE ABLE TO DIFFERENTIATE INTO MULTIPLE MESODERMAL TISSUES, INCLUDING BONE AND CARTILAGE. THERE IS EVIDENCE THAT THESE CELLS ARE ABLE TO BREAK GERM LAYER COMMITMENT AND DIFFERENTIATE INTO CELLS EXPRESSING NEUROECTODERMAL PROPERTIES. THERE IS STILL DEBATE ABOUT WHETHER THIS RESULTS FROM CELL FUSION, ABERRANT MARKER GENE EXPRESSION OR REAL NEUROECTODERMAL DIFFERENTIATION. HERE WE EXTEND OUR WORK ON NEUROECTODERMAL CONVERSION OF ADULT HMSCS IN VITRO BY EVALUATING VARIOUS EPIGENETIC CONVERSION PROTOCOLS USING QUANTITATIVE RT-PCR AND IMMUNOCYTOCHEMISTRY. UNDIFFERENTIATED HMSCS EXPRESSED HIGH LEVELS OF FIBRONECTIN AS WELL AS SEVERAL NEUROECTODERMAL GENES COMMONLY USED TO CHARACTERIZE NEURAL CELL TYPES, SUCH AS NESTIN, BETA-TUBULIN III, AND GFAP, SUGGESTING THAT HMSCS RETAIN THE ABILITY TO DIFFERENTIATE INTO NEUROECTODERMAL CELL TYPES. PROTOCOLS USING A DIRECT DIFFERENTIATION OF HMSCS INTO A NEURAL PHENOTYPE FAILED TO INDUCE SIGNIFICANT CHANGES IN MORPHOLOGY AND/OR EXPRESSION OF MARKERS OF EARLY AND MATURE GLIAL/NEURONAL CELLS TYPES. IN CONTRAST, A MULTISTEP PROTOCOL WITH CONVERSION OF HMSCS INTO A NEURAL STEM CELL-LIKE POPULATION AND SUBSEQUENT TERMINAL DIFFERENTIATION IN MATURE GLIA AND NEURONS GENERATED RELEVANT MORPHOLOGICAL CHANGES AS WELL AS SIGNIFICANT INCREASE OF EXPRESSION LEVELS OF MARKER GENES FOR EARLY AND LATE NEURAL CELL TYPES, SUCH AS NESTIN, NEUROGENIN2, MBP, AND MAP2AB, ACCOMPANIED BY A LOSS OF THEIR MESENCHYMAL PROPERTIES. OUR DATA PROVIDE AN IMPETUS FOR DIFFERENTIATING HMSCS IN VITRO INTO MATURE NEUROECTODERMAL CELLS. NEUROECTODERMALLY CONVERTED HMSCS MAY THEREFORE ULTIMATELY HELP IN TREATING ACUTE AND CHRONIC NEURODEGENERATIVE DISEASES. ANALYSIS OF MARKER GENE EXPRESSION FOR CHARACTERIZATION OF NEURAL CELLS DERIVED FROM MSCS HAS TO TAKE INTO ACCOUNT THAT SEVERAL EARLY AND LATE NEUROECTODERMAL GENES ARE ALREADY EXPRESSED IN UNDIFFERENTIATED MSCS. 2006 6 2072 40 EPIGENETIC CONVERSION OF HUMAN ADULT BONE MESODERMAL STROMAL CELLS INTO NEUROECTODERMAL CELL TYPES FOR REPLACEMENT THERAPY OF NEURODEGENERATIVE DISORDERS. TISSUE-SPECIFIC STEM CELLS, SUCH AS BONE MARROW-DERIVED MESODERMAL STROMAL CELLS (MSCS), ARE THOUGHT TO BE LINEAGE RESTRICTED AND, THEREFORE, COULD ONLY BE DIFFERENTIATED INTO CELL TYPES OF THE TISSUE OF ORIGIN. SEVERAL RECENT STUDIES, HOWEVER, SUGGEST THAT THESE TYPES OF STEM CELLS MIGHT BE ABLE TO BREAK BARRIERS OF GERM LAYER COMMITMENT AND DIFFERENTIATE IN VITRO AND/OR IN VIVO INTO CELLS OF DIFFERENT TISSUES, SUCH AS NEUROECTODERMAL CELL TYPES. RECENTLY, PROTOCOLS FOR HIGH-YIELD GENERATION OF UNDIFFERENTIATED NEURAL STEM CELL (NSC)-LIKE CELLS FROM MSCS OF PRIMATE AND HUMAN ORIGIN WERE REPORTED. UNDIFFERENTIATED NSCS ARE COMMONLY USED AND ARE MORE SUITABLE FOR NEUROTRANSPLANTATION COMPARED WITH FULLY DIFFERENTIATED NEURAL CELLS, AS DIFFERENTIATED NEURAL CELLS ARE WELL KNOWN TO POORLY SURVIVE DETACHMENT AND SUBSEQUENT TRANSPLANTATION PROCEDURES. THESE HUMAN MSC-DERIVED NSC-LIKE CELLS (MSC-NSCS) GROW IN NEUROSPHERE-LIKE STRUCTURES AND EXPRESS HIGH LEVELS OF EARLY NEUROECTODERMAL MARKERS, BUT LOSE CHARACTERISTICS OF MSCS. IN THE PRESENCE OF SELECTED GROWTH FACTORS, HUMAN MSC-NSCS CAN BE DIFFERENTIATED INTO THE THREE MAIN NEURAL PHENOTYPES: ASTROGLIA, OLIGODENDROGLIA AND NEURONS. COMPARED WITH DIRECT DIFFERENTIATION OF HUMAN MSCS INTO MATURE NEURAL CELLS, THE CONVERSION STEP SEEMS TO BE ESSENTIAL TO GENERATE MATURE FUNCTIONAL NEUROECTODERMAL CELLS. THIS REVIEW DESCRIBES THE TECHNIQUES FOR THE CONVERSION OF HUMAN MSCS INTO NSCS AND SUMMARISES THE DATA ON EPIGENETIC CONVERSION OF HUMAN MSCS INTO IMMATURE NEUROECTODERMAL CELLS. THESE CELLS PROVIDE A POWERFUL TOOL FOR INVESTIGATING THE MOLECULAR MECHANISMS OF NEURAL DIFFERENTIATION, AND MIGHT SERVE AS AN AUTOLOGOUS CELL SOURCE TO TREAT ACUTE AND CHRONIC NEURODEGENERATIVE DISEASES. 2006 7 4073 20 MATERNAL EATING DISORDERS AFFECT OFFSPRING CORD BLOOD DNA METHYLATION: A PROSPECTIVE STUDY. BACKGROUND: EATING DISORDERS (ED) ARE CHRONIC PSYCHIATRIC DISORDERS, COMMON AMONGST WOMEN OF REPRODUCTIVE AGE. ED IN PREGNANCY ARE ASSOCIATED WITH POOR NUTRITION AND ABNORMAL INTRAUTERINE GROWTH. INCREASING EVIDENCE ALSO SHOWS OFFSPRING OF WOMEN WITH ED HAVE ADVERSE DEVELOPMENTAL AND BIRTH OUTCOMES. WE SOUGHT TO CARRY OUT THE FIRST STUDY INVESTIGATING DNA METHYLATION IN OFFSPRING OF WOMEN WITH ED. WE COMPARED CORD BLOOD DNA METHYLATION IN OFFSPRING OF WOMEN WITH ACTIVE ED (N = 21), PAST ED (N = 43) AND AGE- AND SOCIAL CLASS-MATCHED CONTROLS (N = 126) AS PART OF THE AVON LONGITUDINAL STUDY OF PARENTS AND CHILDREN. RESULTS: OFFSPRING OF WOMEN WITH BOTH ACTIVE AND PAST ED HAD LOWER WHOLE-GENOME METHYLATION COMPARED TO CONTROLS (ACTIVE ED 49.1% (95% CONFIDENCE INTERVALS 50.5-47.7%), PAST ED 49.2% (95% CI 50.7-47.7.0%), CONTROLS 52.4% (95% CI 53.0%-51.0%)). AMONGST OFFSPRING OF ED WOMEN, THOSE BORN TO WOMEN WITH RESTRICTIVE-TYPE AND PURGING-TYPE ED HAD LOWER METHYLATION LEVELS COMPARED TO THOSE OF CONTROLS. OFFSPRING OF WOMEN WITH AN ACTIVE RESTRICTIVE ED IN PREGNANCY HAD LOWER WHOLE-GENOME METHYLATION COMPARED TO OFFSPRING OF WOMEN WITH PAST RESTRICTIVE ED. WE OBSERVED DECREASED METHYLATION AT THE DHCR24 LOCUS IN OFFSPRING OF WOMEN WITH ACTIVE PREGNANCY ED (EFFECT SIZE (ES) = - 0.124, P = 6.94 X 10(-8)) AND INCREASED METHYLATION AT THE LGALS2 LOCUS IN OFFSPRING OF WOMEN WITH PAST ED (ES = 0.07, P = 3.74 X 10(-7)) COMPARED TO CONTROLS. CONCLUSIONS: MATERNAL ACTIVE AND PAST ED ARE ASSOCIATED WITH DIFFERENCES IN OFFSPRING WHOLE-GENOME METHYLATION. OUR RESULTS SHOW ALTERED DNA METHYLATION IN LOCI RELEVANT TO METABOLISM; THESE MIGHT BE BIOMARKERS OF DISRUPTED METABOLIC PATHWAYS IN OFFSPRING OF ED MOTHERS. FURTHER WORK IS NEEDED TO EXAMINE POTENTIAL MECHANISMS AND FUNCTIONAL OUTCOMES OF THE OBSERVED METHYLATION PATTERNS. 2017 8 2786 20 EZH2 RESTRICTS THE SMOOTH MUSCLE LINEAGE DURING MOUSE LUNG MESOTHELIAL DEVELOPMENT. DURING DEVELOPMENT, THE LUNG MESODERM GENERATES A VARIETY OF CELL LINEAGES, INCLUDING AIRWAY AND VASCULAR SMOOTH MUSCLE. EPIGENETIC CHANGES IN ADULT LUNG MESODERMAL LINEAGES ARE THOUGHT TO CONTRIBUTE TOWARDS DISEASES SUCH AS IDIOPATHIC PULMONARY FIBROSIS AND CHRONIC OBSTRUCTIVE PULMONARY DISEASE, ALTHOUGH THE FACTORS THAT REGULATE EARLY LUNG MESODERM DEVELOPMENT ARE UNKNOWN. WE SHOW IN MOUSE THAT THE PRC2 COMPONENT EZH2 IS REQUIRED TO RESTRICT SMOOTH MUSCLE DIFFERENTIATION IN THE DEVELOPING LUNG MESOTHELIUM. MESODERMAL LOSS OF EZH2 LEADS TO THE FORMATION OF ECTOPIC SMOOTH MUSCLE IN THE SUBMESOTHELIAL REGION OF THE DEVELOPING LUNG MESODERM. LOSS OF EZH2 SPECIFICALLY IN THE DEVELOPING MESOTHELIUM REVEALS A MESOTHELIAL CELL-AUTONOMOUS ROLE FOR EZH2 IN REPRESSION OF THE SMOOTH MUSCLE DIFFERENTIATION PROGRAM. LOSS OF EZH2 DEREPRESSES EXPRESSION OF MYOCARDIN AND TBX18, WHICH ARE IMPORTANT REGULATORS OF SMOOTH MUSCLE DIFFERENTIATION FROM THE MESOTHELIUM AND RELATED CELL LINEAGES. TOGETHER, THESE FINDINGS UNCOVER AN EZH2-DEPENDENT MECHANISM TO RESTRICT THE SMOOTH MUSCLE GENE EXPRESSION PROGRAM IN THE DEVELOPING MESOTHELIUM AND ALLOW APPROPRIATE CELL FATE DECISIONS TO OCCUR IN THIS MULTIPOTENT MESODERM LINEAGE. 2016 9 930 30 CHRONIC IRRADIATION OF HUMAN CELLS REDUCES HISTONE LEVELS AND DEREGULATES GENE EXPRESSION. OVER THE PAST DECADES, THERE HAVE BEEN HUGE ADVANCES IN UNDERSTANDING CELLULAR RESPONSES TO IONISING RADIATION (IR) AND DNA DAMAGE. THESE STUDIES, HOWEVER, WERE MOSTLY EXECUTED WITH CELL LINES AND MICE USING SINGLE OR MULTIPLE ACUTE DOSES OF RADIATION. HENCE, RELATIVELY LITTLE IS KNOWN ABOUT HOW CONTINUOUS EXPOSURE TO LOW DOSE IONISING RADIATION AFFECTS NORMAL CELLS AND ORGANISMS, EVEN THOUGH OUR CELLS ARE CONSTANTLY EXPOSED TO LOW LEVELS OF RADIATION. WE ADDRESSED THIS ISSUE BY EXAMINING THE CONSEQUENCES OF EXPOSING HUMAN PRIMARY CELLS TO CONTINUOUS IONISING GAMMA-RADIATION DELIVERED AT 6-20 MGY/H. ALTHOUGH THESE DOSE RATES ARE ESTIMATED TO INFLICT FEWER THAN A SINGLE DNA DOUBLE-STRAND BREAK (DSB) PER HOUR PER CELL, THEY STILL CAUSED DOSE-DEPENDENT REDUCTIONS IN CELL PROLIFERATION AND INCREASED CELLULAR SENESCENCE. WE CONCOMITANTLY OBSERVED HISTONE PROTEIN LEVELS TO REDUCE BY UP TO 40%, WHICH IN CONTRAST TO PREVIOUS OBSERVATIONS, WAS NOT MAINLY DUE TO PROTEIN DEGRADATION BUT INSTEAD CORRELATED WITH REDUCED HISTONE GENE EXPRESSION. HISTONE REDUCTIONS WERE ACCOMPANIED BY ENLARGED NUCLEAR SIZE PARALLELED BY AN INCREASE IN GLOBAL TRANSCRIPTION, INCLUDING THAT OF PRO-INFLAMMATORY GENES. THUS, CHRONIC IRRADIATION, EVEN AT LOW DOSE-RATES, CAN INDUCE CELL SENESCENCE AND ALTER GENE EXPRESSION VIA A HITHERTO UNCHARACTERISED EPIGENETIC ROUTE. THESE FEATURES OF CHRONIC RADIATION REPRESENT A NEW ASPECT OF RADIATION BIOLOGY. 2020 10 6555 29 TRANSGENERATIONAL EFFECTS OF GAMMA RADIATION DOSE AND DOSE RATE ON DROSOPHILA FLIES IRRADIATED AT AN EARLY EMBRYONAL STAGE. IONIZING RADIATION (IR) KILLS CELLS MAINLY THROUGH INDUCTION OF DNA DAMAGES AND THE SURVIVING CELLS MAY SUFFER FROM MUTATIONS. TRANSGENERATIONAL EFFECTS OF IR ARE WELL DOCUMENTED, BUT THE EXACT MECHANISMS UNDERLYING THEM ARE LESS WELL UNDERSTOOD; THEY INCLUDE INDUCTION OF MUTATIONS IN GERM CELLS AND EPIGENETIC INHERITANCE. PREVIOUSLY, EFFECTS IN THE OFFSPRING OF MICE AND ZEBRAFISH EXPOSED TO IR HAVE BEEN REPORTED. A FEW STUDIES ALSO SHOWED INDICATIONS OF TRANSGENERATIONAL EFFECTS OF RADIATION IN HUMANS, PARTICULARLY IN NUCLEAR POWER WORKERS. IN THE PRESENT PROJECT, SHORT- AND LONG-TERM EFFECTS OF LOW-DOSE-RATE (LDR; 50 AND 97 MGY/H) AND HIGH-DOSE-RATE (HDR; 23.4, 47.1 AND 495 GY/H) IR IN DROSOPHILA EMBRYOS WERE INVESTIGATED. THE EMBRYOS WERE IRRADIATED AT DIFFERENT DOSES AND DOSE RATES AND RADIOSENSITIVITY AT DIFFERENT DEVELOPMENTAL STAGES WAS INVESTIGATED. ALSO, THE SURVIVAL OF LARVAE, PUPAE AND ADULTS DEVELOPED FROM EMBRYOS IRRADIATED AT AN EARLY STAGE (30 MIN AFTER EGG LAYING) WERE STUDIED. THE LARVAL CRAWLING AND PUPATION HEIGHT ASSAYS WERE APPLIED TO INVESTIGATE RADIATION EFFECTS ON LARVAL LOCOMOTION AND PUPATION BEHAVIOR, RESPECTIVELY. IN PARALLEL, THE OFFSPRING FROM 3 GY IRRADIATED EARLY-STAGE EMBRYOS WERE FOLLOWED UP TO 12 GENERATIONS AND ABNORMAL PHENOTYPES WERE STUDIED. ACUTE EXPOSURE OF EMBRYOS AT DIFFERENT STAGES OF DEVELOPMENT SHOWED THAT THE EARLY STAGE EMBRYO IS THE MOST SENSITIVE. THE EFFECTS ON LARVAL LOCOMOTION SHOWED NO SIGNIFICANT DIFFERENCES BETWEEN THE DOSE RATES BUT A SIGNIFICANT DECREASE OF LOCOMOTION ACTIVITY ABOVE 7 GY WAS OBSERVED. THE RESULTS INDICATE THAT EMBRYOS EXPOSED TO THE LOW DOSE RATES HAVE SHORTER ECLOSION TIMES. AT THE SAME CUMULATIVE DOSE (1 UP TO 7 GY), HDR IS MORE EMBRYOTOXIC THAN LDR. WE ALSO FOUND A RADIATION-INDUCED DEPIGMENTATION ON MALES (A5 SEGMENT OF THE DORSAL ABDOMEN, A5PIG(-)) THAT CAN BE TRANSMITTED UP TO 12 GENERATIONS. THE PHENOMENON DOES NOT FOLLOW THE CLASSICAL MENDELIAN LAWS OF SEGREGATION. 2022 11 80 39 A NEW ROLE FOR THE P2Y-LIKE GPR17 RECEPTOR IN THE MODULATION OF MULTIPOTENCY OF OLIGODENDROCYTE PRECURSOR CELLS IN VITRO. OLIGODENDROCYTE PRECURSOR CELLS (OPCS, ALSO CALLED NG2 CELLS) ARE SCATTERED THROUGHOUT BRAIN PARENCHYMA, WHERE THEY FUNCTION AS A RESERVOIR TO REPLACE LOST OR DAMAGED OLIGODENDROCYTES, THE MYELIN-FORMING CELLS. THE HYPOTHESIS THAT, UNDER SOME CIRCUMSTANCES, OPCS CAN ACTUALLY BEHAVE AS MULTIPOTENT CELLS, THUS GENERATING ASTROCYTES AND NEURONS AS WELL, HAS ARISEN FROM SOME IN VITRO AND IN VIVO EVIDENCE, BUT THE MOLECULAR PATHWAYS CONTROLLING THIS ALTERNATIVE FATE OF OPCS ARE NOT FULLY UNDERSTOOD. THEIR IDENTIFICATION WOULD OPEN NEW OPPORTUNITIES FOR NEURONAL REPLACE STRATEGIES, BY FOSTERING THE INTRINSIC ABILITY OF THE BRAIN TO REGENERATE. HERE, WE SHOW THAT THE ANTI-EPILEPTIC EPIGENETIC MODULATOR VALPROIC ACID (VPA) CAN PROMOTE THE GENERATION OF NEW NEURONS FROM NG2(+) OPCS UNDER NEUROGENIC PROTOCOLS IN VITRO, THROUGH THEIR INITIAL DE-DIFFERENTIATION TO A STEM CELL-LIKE PHENOTYPE THAT THEN EVOLVES TO "HYBRID" CELL POPULATION, SHOWING OPC MORPHOLOGY BUT EXPRESSING THE NEURONAL MARKER BETAIII-TUBULIN AND THE GPR17 RECEPTOR, A KEY DETERMINANT IN DRIVING OPC TRANSITION TOWARDS MYELINATING OLIGODENDROCYTES. UNDER THESE CONDITIONS, THE PHARMACOLOGICAL BLOCKADE OF THE P2Y-LIKE RECEPTOR GPR17 BY CANGRELOR, A DRUG RECENTLY APPROVED FOR HUMAN USE, PARTIALLY MIMICS THE EFFECTS MEDIATED BY VPA THUS ACCELERATING CELLS' NEUROGENIC CONVERSION. THESE DATA SHOW A CO-LOCALIZATION BETWEEN NEURONAL MARKERS AND GPR17 IN VITRO, AND SUGGEST THAT, BESIDES ITS INVOLVEMENT IN OLIGODENDROGENESIS, GPR17 CAN DRIVE THE FATE OF NEURAL PRECURSOR CELLS BY INSTRUCTING PRECURSORS TOWARDS THE NEURONAL LINEAGE. BEING A MEMBRANE RECEPTOR, GPR17 REPRESENTS AN IDEAL "DRUGGABLE" TARGET TO BE EXPLOITED FOR INNOVATIVE REGENERATIVE APPROACHES TO ACUTE AND CHRONIC BRAIN DISEASES. 2016 12 1850 27 ELECTROACUPUNCTURE AMELIORATES DEPRESSION-LIKE BEHAVIORS COMORBID TO CHRONIC NEUROPATHIC PAIN VIA TET1-MEDIATED RESTORATION OF ADULT NEUROGENESIS. ALTHOUGH ELECTROACUPUNCTURE (EA) STIMULATION IS A WIDELY USED THERAPY FOR CHRONIC PAIN AND COMORBID PSYCHIATRIC DISORDERS, ITS LONG-TERM EFFECTS ON CHRONIC NEUROPATHIC PAIN-INDUCED DEPRESSION AND THE UNDERLYING MECHANISMS REMAIN ELUSIVE. IN THE PRESENT STUDY, WE FOUND THAT EA STIMULATION WAS ABLE TO RESTORE ADULT NEUROGENESIS IN THE VENTRAL DENTATE GYRUS (DG), BY BOTH INCREASING NEURONAL DIFFERENTIATION AND RESTORING THE NORMAL MORPHOLOGY OF NEWBORN DENDRITES, IN MICE WITH SPARED NERVE INJURY SURGERY. BY ABLATING THE NESTIN+ NEURAL STEM CELLS (NSCS) VIA DIPHTHERIA TOXIN FRAGMENT A EXPRESSION, WE FURTHER PROVED THAT NEUROGENESIS IN THE VENTRAL DG WAS CRUCIAL TO THE LONG-TERM, BUT NOT THE IMMEDIATE ANTIDEPRESSANT EFFECT OF EA, NOR WAS IT ASSOCIATED WITH NOCICEPTION. FURTHERMORE, WE FOUND THAT THE RESTORATION OF NEUROGENESIS WAS DEPENDENT ON TET1-MEDIATED EPIGENETIC MODIFICATION UPON EA TREATMENT. TET1 COULD BIND TO THE PROMOTER OF THE PROX1 GENE, THUS CATALYZING ITS DEMETHYLATION AND FACILITATING ITS EXPRESSION, WHICH FINALLY CONTRIBUTED TO THE RESTORATION OF NEUROGENESIS AND AMELIORATION OF DEPRESSION-LIKE BEHAVIORS INDUCED BY CHRONIC NEUROPATHIC PAIN. THUS, WE CONCLUDE THAT EA STIMULATION RESTORES INHIBITED TET1 EXPRESSION IN HIPPOCAMPAL NSCS OF MICE WITH CHRONIC NEUROPATHIC PAIN, AND INCREASED TET1 EXPRESSION AMELIORATES HYPERMETHYLATION OF PROX1 AND RESTORES NORMAL ADULT NEUROGENESIS IN THE VENTRAL DG, WHICH CONTRIBUTES TO THE LONG-TERM ANTIDEPRESSANT EFFECT OF EA. 2023 13 892 42 CHRONIC ETHANOL EXPOSURE ALTERS DNA METHYLATION IN NEURAL STEM CELLS: ROLE OF MOUSE STRAIN AND SEX. PRENATAL ALCOHOL EXPOSURE (PAE) IS CONSIDERED AS A RISK FACTOR FOR THE DEVELOPMENT OF FETAL ALCOHOL SPECTRUM DISORDERS (FASD). EVIDENCE INDICATES THAT PAE AFFECTS EPIGENETIC MECHANISMS (SUCH AS DNA METHYLATION) AND ALTERS THE NORMAL DIFFERENTIATION AND DEVELOPMENT OF NEURAL STEM CELLS (NSC) IN THE FETAL BRAIN. HOWEVER, PAE EFFECTS DEPEND ON SEVERAL FACTORS SUCH AS SEX AND STRAIN OF THE STUDIED SUBJECTS. HERE, WE INVESTIGATED WHETHER MURINE SEX AND STRAIN CONTRIBUTE TO THE EFFECTS OF CHRONIC ETHANOL EXPOSURE ON DNA METHYLATION MACHINERY OF DIFFERENTIATING NSC. FURTHER, THE EFFECTS OF PAE ON GLIAL LINEAGE (INCLUDING BOTH ASTROCYTES AND OLIGODENDROCYTES) IN A SEX- AND STRAIN-DEPENDENT MANNER HAVE NOT BEEN STUDIED YET. TO EXAMINE THE EFFECTS OF CHRONIC ETHANOL EXPOSURE ON GLIOGENESIS, WE EXPOSED DIFFERENTIATING NSC TO GLIO-INDUCTIVE CULTURE CONDITIONS. APPLYING A STANDARD IN VITRO MODEL SYSTEM, WE TREATED MALE AND FEMALE DIFFERENTIATING NSC (OBTAINED FROM THE FOREBRAIN OF CD1 AND C57BL/6 EMBRYOS AT EMBRYONIC DAY 14.5) WITH CHRONIC ETHANOL EXPOSURE (70 MM) FOR 8 DAYS. WE SHOW THAT ETHANOL INDUCES GLOBAL DNA HYPOMETHYLATION, WHILE ALTERING THE EXPRESSION OF DNA METHYLATION-RELATED GENES IN A SEX- AND STRAIN-SPECIFIC MANNER. THE OBSERVED CHANGE IN CELLULAR DNA METHYLATION LEVELS WAS ASSOCIATED WITH ALTERED EXPRESSION OF GLIAL MARKERS CNPASE, GFAP, AND OLIG2 IN CD1 (BUT NOT C57BL/6) CELLS. WE CONCLUDE THAT THE IMPACT OF ETHANOL EFFECT ON DNA METHYLATION IS DEPENDENT ON CELLULAR SEX AND STRAIN. ALSO, ETHANOL IMPACT ON NEURAL STEM CELL FATE COMMITMENT WAS ONLY DETECTED IN CELLS ISOLATED FROM CD1 MOUSE STRAIN, BUT NOT IN C57BL/6 CELLS. THE RESULTS OF THE CURRENT STUDY PROVIDE EVIDENCE THAT SEX AND STRAIN OF RODENTS (C57BL/6 AND CD1) DURING GESTATION ARE IMPORTANT FACTORS, WHICH AFFECT ALCOHOL EFFECTS ON NSC DIFFERENTIATION AND DNA METHYLATION. RESULTS OF THIS STUDY MAY ALSO HELP IN INTERPRETING DATA ON THE DEVELOPMENTAL TOXICITY OF MANY COMPOUNDS DURING THE GESTATIONAL PERIOD. 2020 14 6758 23 WNT SIGNALING IN STEM CELL BIOLOGY AND REGENERATIVE MEDICINE. WNT FAMILY MEMBERS ARE SECRETED-TYPE GLYCOPROTEINS TO ORCHESTRATE EMBRYOGENESIS, TO MAINTAIN HOMEOSTASIS, AND TO INDUCE PATHOLOGICAL CONDITIONS. FZD1, FZD2, FZD3, FZD4, FZD5, FZD6, FZD7, FZD8, FZD9, FZD10, LRP5, LRP6, AND ROR2 ARE TRANSMEMBRANE RECEPTORS TRANSDUCING WNT SIGNALS BASED ON LIGAND-DEPENDENT PREFERENTIALITY FOR CAVEOLIN- OR CLATHRIN-MEDIATED ENDOCYTOSIS. WNT SIGNALS ARE TRANSDUCED TO CANONICAL PATHWAY FOR CELL FATE DETERMINATION, AND TO NON-CANONICAL PATHWAYS FOR REGULATION OF PLANAR CELL POLARITY, CELL ADHESION, AND MOTILITY. MYC, CCND1, AXIN2, FGF20, WISP1, JAG1, DKK1 AND GLUCAGON ARE TARGET GENES OF CANONICAL WNT SIGNALING CASCADE, WHILE CD44, VIMENTIN AND STX5 ARE TARGET GENES OF NON-CANONICAL WNT SIGNALING CASCADES. HOWEVER, TARGET GENES OF WNT SIGNALING CASCADES ARE DETERMINED IN A CONTEXT-DEPENDENT MANNER DUE TO EXPRESSION PROFILE OF TRANSCRIPTION FACTORS AND EPIGENETIC STATUS. WNT SIGNALING CASCADES NETWORK WITH NOTCH, FGF, BMP AND HEDGEHOG SIGNALING CASCADES TO REGULATE THE BALANCE OF STEM CELLS AND PROGENITOR CELLS. HERE WNT SIGNALING IN EMBRYONIC STEM CELLS, NEURAL STEM CELLS, MESENCHYMAL STEM CELLS, HEMATOPOIETIC STEM CELLS, AND INTESTINAL STEM CELLS WILL BE REVIEWED. WNT3, WNT5A AND WNT10B ARE EXPRESSED IN UNDIFFERENTIATED HUMAN EMBRYONIC STEM CELLS, WHILE WNT6, WNT8B AND WNT10B IN ENDODERM PRECURSOR CELLS. WNT6 IS EXPRESSED IN INTESTINAL CRYPT REGION FOR STEM OR PROGENITOR CELLS. TNF/ALPHA-WNT10B SIGNALING IS A NEGATIVE FEEDBACK LOOP TO MAINTAIN HOMEOSTASIS OF ADIPOSE TISSUE AND GASTROINTESTINAL MUCOSA WITH CHRONIC INFLAMMATION. RECOMBINANT WNT PROTEIN OR WNT MIMETIC (CIRCULAR PEPTIDE, SMALL MOLECULE COMPOUND, OR RNA APTAMER) IN COMBINATION WITH NOTCH MIMETIC, FGF PROTEIN, AND BMP PROTEIN OPENS A NEW WINDOW TO TISSUE ENGINEERING FOR REGENERATIVE MEDICINE. 2008 15 2882 38 G-PROTEIN-COUPLED RECEPTOR GPR17 REGULATES OLIGODENDROCYTE DIFFERENTIATION IN RESPONSE TO LYSOLECITHIN-INDUCED DEMYELINATION. OLIGODENDROCYTES ARE THE MYELIN-PRODUCING CELLS OF THE CENTRAL NERVOUS SYSTEM (CNS). A VARIETY OF BRAIN DISORDERS FROM "CLASSICAL" DEMYELINATING DISEASES, SUCH AS MULTIPLE SCLEROSIS, STROKE, SCHIZOPHRENIA, DEPRESSION, DOWN SYNDROME AND AUTISM, ARE SHOWN MYELINATION DEFECTS. OLIGODENDROCYTE MYELINATION IS REGULATED BY A COMPLEX INTERPLAY OF INTRINSIC, EPIGENETIC AND EXTRINSIC FACTORS. GPR17 (G PROTEIN-COUPLED RECEPTOR 17) IS A G PROTEIN-COUPLED RECEPTOR, AND HAS BEEN IDENTIFIED TO BE A REGULATOR FOR OLIGODENDROCYTE DEVELOPMENT. HERE, WE DEMONSTRATE THAT THE ABSENCE OF GPR17 ENHANCES REMYELINATION IN VIVO WITH A TOXIN-INDUCED MODEL WHEREBY FOCAL DEMYELINATED LESIONS ARE GENERATED IN SPINAL CORD WHITE MATTER OF ADULT MICE BY LOCALIZED INJECTION OF LPC(L-A-LYSOPHOSPHATIDYLCHOLINE). THE INCREASED EXPRESSION OF THE ACTIVATED FORM OF ERK1/2 (PHOSPHO-ERK1/2) IN LESION AREAS SUGGESTED THE POTENTIAL ROLE OF ERK1/2 ACTIVITY ON THE GPR17-DEPENDENT MODULATION OF MYELINATION. THE ABSENCE OF GPR17 ENHANCES REMYELINATION IS CORRELATE WITH THE ACTIVATED ERK1/2 (PHOSPHO-ERK1/2).BEING A MEMBRANE RECEPTOR, GPR17 REPRESENTS AN IDEAL DRUGGABLE TARGET TO BE EXPLOITED FOR INNOVATIVE REGENERATIVE APPROACHES TO ACUTE AND CHRONIC CNS DISEASES. 2018 16 5032 26 PERTURBED TRANSCRIPTIONAL PROFILES AFTER CHRONIC LOW DOSE RATE RADIATION IN MICE. ADVERSE HEALTH OUTCOMES OF IONIZING RADIATION GIVEN CHRONICALLY AT LOW DOSE RATES ARE HIGHLY DEBATED, A CONTROVERSY ALSO RELEVANT FOR OTHER STRESSORS. INCREASED KNOWLEDGE IS NEEDED FOR A MORE COMPREHENSIVE UNDERSTANDING OF THE DAMAGING POTENTIAL OF IONIZING RADIATION FROM ALL DOSE RATES AND DOSES. THERE IS A LACK OF RELEVANT LOW DOSE RATE DATA THAT IS PARTLY ASCRIBED TO THE RARITY OF EXPOSURE FACILITIES ALLOWING CHRONIC LOW DOSE RATE EXPOSURES. USING THE FIGARO FACILITY, WE ASSESSED EARLY (ONE DAY POST-RADIATION) AND LATE (RECOVERY TIME OF 100-200 DAYS) HEPATIC GENOME-WIDE TRANSCRIPTIONAL PROFILES IN MALE MICE OF TWO STRAINS (CBA/CAOLAHSD AND C57BL/6NHSD) EXPOSED CHRONICALLY TO A LOW DOSE RATE (2.5 MGY/H; 1200H, LDR), A MID-DOSE RATE (10 MGY/H; 300H, MDR) AND ACUTELY TO A HIGH DOSE RATE (100 MGY/H; 30H, HDR) OF GAMMA IRRADIATION, GIVEN TO AN EQUIVALENT TOTAL DOSE OF 3 GY. DOSE-RATE AND STRAIN-SPECIFIC TRANSCRIPTIONAL RESPONSES WERE IDENTIFIED. DIFFERENTLY MODULATED TRANSCRIPTIONAL RESPONSES ACROSS ALL DOSE RATE EXPOSURE GROUPS WERE EVIDENT BY THE REPRESENTATION OF FUNCTIONAL BIOLOGICAL PATHWAYS. EVIDENCE OF CHANGED EPIGENETIC REGULATION (GLOBAL DNA METHYLATION) WAS NOT DETECTED. A PERIOD OF RECOVERY MARKEDLY REDUCED THE NUMBER OF DIFFERENTIALLY EXPRESSED GENES. USING ENRICHMENT ANALYSIS TO IDENTIFY THE FUNCTIONAL SIGNIFICANCE OF THE MODULATED GENES, PERTURBED SIGNALING PATHWAYS ASSOCIATED WITH BOTH CANCER AND NON-CANCER EFFECTS WERE OBSERVED, SUCH AS LIPID METABOLISM AND INFLAMMATION. THESE PATHWAYS WERE SEEN AFTER CHRONIC LOW DOSE RATE AND WERE NOT RESTRICTED TO THE ACUTE HIGH DOSE RATE EXPOSURE. THE TRANSCRIPTIONAL RESPONSE INDUCED BY CHRONIC LOW DOSE RATE IONIZING RADIATION SUGGESTS CONTRIBUTION TO CONDITIONS SUCH AS CARDIOVASCULAR DISEASES. WE CONTRIBUTE WITH NOVEL GENOME WIDE TRANSCRIPTIONAL DATA HIGHLIGHTING DOSE-RATE-SPECIFIC RADIATION RESPONSES AND EMPHASIZE THE IMPORTANCE OF CONSIDERING BOTH DOSE RATE, DURATION OF EXPOSURE, AND VARIABILITY IN SUSCEPTIBILITY WHEN ASSESSING RISKS FROM IONIZING RADIATION. 2021 17 2856 35 FROM METHYLATION TO MYELINATION: EPIGENOMIC AND TRANSCRIPTOMIC PROFILING OF CHRONIC INACTIVE DEMYELINATED MULTIPLE SCLEROSIS LESIONS. IN THE PROGRESSIVE PHASE OF MULTIPLE SCLEROSIS (MS), THE HAMPERED DIFFERENTIATION CAPACITY OF OLIGODENDROCYTE PRECURSOR CELLS (OPCS) EVENTUALLY RESULTS IN REMYELINATION FAILURE. WE HAVE PREVIOUSLY SHOWN THAT DNA METHYLATION OF ID2/ID4 IS HIGHLY INVOLVED IN OPC DIFFERENTIATION AND REMYELINATION. IN THIS STUDY, WE TOOK AN UNBIASED APPROACH BY DETERMINING GENOME-WIDE DNA METHYLATION PATTERNS WITHIN CHRONICALLY DEMYELINATED MS LESIONS AND INVESTIGATED HOW CERTAIN EPIGENETIC SIGNATURES RELATE TO OPC DIFFERENTIATION CAPACITY. WE COMPARED GENOME-WIDE DNA METHYLATION AND TRANSCRIPTIONAL PROFILES BETWEEN CHRONICALLY DEMYELINATED MS LESIONS AND MATCHED NORMAL-APPEARING WHITE MATTER (NAWM), MAKING USE OF POST-MORTEM BRAIN TISSUE (N = 9/GROUP). DNA METHYLATION DIFFERENCES THAT INVERSELY CORRELATED WITH MRNA EXPRESSION OF THEIR CORRESPONDING GENES WERE VALIDATED FOR THEIR CELL-TYPE SPECIFICITY IN LASER-CAPTURED OPCS USING PYROSEQUENCING. THE CRISPR-DCAS9-DNMT3A/TET1 SYSTEM WAS USED TO EPIGENETICALLY EDIT HUMAN-IPSC-DERIVED OLIGODENDROCYTES TO ASSESS THE EFFECT ON CELLULAR DIFFERENTIATION. OUR DATA SHOW HYPERMETHYLATION OF CPGS WITHIN GENES THAT CLUSTER IN GENE ONTOLOGIES RELATED TO MYELINATION AND AXON ENSHEATHMENT. CELL TYPE-SPECIFIC VALIDATION INDICATES A REGION-DEPENDENT HYPERMETHYLATION OF MBP, ENCODING FOR MYELIN BASIC PROTEIN, IN OPCS OBTAINED FROM WHITE MATTER LESIONS COMPARED TO NAWM-DERIVED OPCS. BY ALTERING THE DNA METHYLATION STATE OF SPECIFIC CPGS WITHIN THE PROMOTOR REGION OF MBP, USING EPIGENETIC EDITING, WE SHOW THAT CELLULAR DIFFERENTIATION AND MYELINATION CAN BE BIDIRECTIONALLY MANIPULATED USING THE CRISPR-DCAS9-DNMT3A/TET1 SYSTEM IN VITRO. OUR DATA INDICATE THAT OPCS WITHIN CHRONICALLY DEMYELINATED MS LESIONS ACQUIRE AN INHIBITORY PHENOTYPE, WHICH TRANSLATES INTO HYPERMETHYLATION OF CRUCIAL MYELINATION-RELATED GENES. ALTERING THE EPIGENETIC STATUS OF MBP CAN RESTORE THE DIFFERENTIATION CAPACITY OF OPCS AND POSSIBLY BOOST (RE)MYELINATION. 2023 18 1488 21 DNA DAMAGE RECOGNITION IN THE RAT ZYGOTE FOLLOWING CHRONIC PATERNAL CYCLOPHOSPHAMIDE EXPOSURE. THE DETRIMENTAL EFFECTS OF PRECONCEPTIONAL PATERNAL EXPOSURE TO THE ALKYLATING ANTICANCER AGENT, CYCLOPHOSPHAMIDE, INCLUDE ABERRANT EPIGENETIC PROGRAMMING, DYSREGULATED ZYGOTIC GENE ACTIVATION, AND ABNORMALITIES IN THE OFFSPRING THAT ARE TRANSMITTED TO THE NEXT GENERATION. THE ADVERSE DEVELOPMENTAL CONSEQUENCES OF GENOMIC INSTABILITIES TRANSMITTED VIA THE SPERMATOZOON EMPHASIZE THE NEED TO ELUCIDATE THE MECHANISMS BY WHICH THE EARLY EMBRYO RECOGNIZES DNA DAMAGE IN THE PATERNAL GENOME. LITTLE INFORMATION EXISTS ON DNA DAMAGE DETECTION IN THE ZYGOTE. WE ASSESSED THE IMPACT OF PATERNAL CYCLOPHOSPHAMIDE EXPOSURE ON PHOSPHORYLATED H2AX (GAMMAH2AX) AND POLY(ADP-RIBOSE) POLYMERASE-1(PARP-1), BIOMARKERS OF DNA DAMAGE, TO DETERMINE THE CAPACITY IN THE RAT ZYGOTE TO RECOGNIZE GENOMIC DAMAGE AND INITIATE A RESPONSE TO DNA LESIONS. AN AMPLIFIED BIPHASIC GAMMAH2AX RESPONSE WAS TRIGGERED IN THE PATERNAL PRONUCLEUS IN ZYGOTES SIRED BY DRUG-TREATED MALES; THE MATERNAL GENOME WAS NOT AFFECTED. PARP-1 IMMUNOREACTIVITY WAS SUBSTANTIALLY ELEVATED IN BOTH PARENTAL GENOMES, COINCIDENT WITH THE SECOND PHASE OF GAMMAH2AX INDUCTION IN EMBRYOS SIRED BY CYCLOPHOSPHAMIDE-EXPOSED SPERMATOZOA. THUS, PATERNAL EXPOSURE TO A DNA DAMAGING AGENT RAPIDLY ACTIVATES SIGNALS IMPLEMENTAL FOR DNA DAMAGE RECOGNITION IN THE ZYGOTE. INEFFICIENT REPAIR OF DNA LESIONS MAY LEAD TO PERSISTENT ALTERATIONS OF THE HISTONE CODE AND CHROMATIN INTEGRITY, RESULTING IN ABERRANT EMBRYOGENESIS. WE PROPOSE THAT THE RESPONSE OF THE EARLY EMBRYO TO DISTURBANCES IN SPERMATOZOAL GENOMIC INTEGRITY PLAYS A VITAL ROLE IN DETERMINING ITS OUTCOME. 2007 19 2117 21 EPIGENETIC HISTONE METHYLATION MODULATES FIBROTIC GENE EXPRESSION. TGF-BETA1-INDUCED EXPRESSION OF EXTRACELLULAR MATRIX (ECM) GENES PLAYS A MAJOR ROLE IN THE DEVELOPMENT OF CHRONIC RENAL DISEASES SUCH AS DIABETIC NEPHROPATHY. ALTHOUGH MANY KEY TRANSCRIPTION FACTORS ARE KNOWN, MECHANISMS INVOLVING THE NUCLEAR CHROMATIN THAT MODULATE ECM GENE EXPRESSION REMAIN UNCLEAR. HERE, WE EXAMINED THE ROLE OF EPIGENETIC CHROMATIN MARKS SUCH AS HISTONE H3 LYSINE METHYLATION (H3KME) IN TGF-BETA1-INDUCED GENE EXPRESSION IN RAT MESANGIAL CELLS UNDER NORMAL AND HIGH-GLUCOSE (HG) CONDITIONS. TGF-BETA1 INCREASED THE EXPRESSION OF THE ECM-ASSOCIATED GENES CONNECTIVE TISSUE GROWTH FACTOR, COLLAGEN-ALPHA1[IOTA], AND PLASMINOGEN ACTIVATOR INHIBITOR-1. INCREASED LEVELS OF CHROMATIN MARKS ASSOCIATED WITH ACTIVE GENES (H3K4ME1, H3K4ME2, AND H3K4ME3), AND DECREASED LEVELS OF REPRESSIVE MARKS (H3K9ME2 AND H3K9ME3) AT THESE GENE PROMOTERS ACCOMPANIED THESE CHANGES IN EXPRESSION. TGF-BETA1 ALSO INCREASED EXPRESSION OF THE H3K4 METHYLTRANSFERASE SET7/9 AND RECRUITMENT TO THESE PROMOTERS. SET7/9 GENE SILENCING WITH SIRNAS SIGNIFICANTLY ATTENUATED TGF-BETA1-INDUCED ECM GENE EXPRESSION. FURTHERMORE, A TGF-BETA1 ANTIBODY NOT ONLY BLOCKED HG-INDUCED ECM GENE EXPRESSION BUT ALSO REVERSED HG-INDUCED CHANGES IN PROMOTER H3KME LEVELS AND SET7/9 OCCUPANCY. TAKEN TOGETHER, THESE RESULTS SHOW THE FUNCTIONAL ROLE OF EPIGENETIC CHROMATIN HISTONE H3KME IN TGF-BETA1-MEDIATED ECM GENE EXPRESSION IN MESANGIAL CELLS UNDER NORMAL AND HG CONDITIONS. PHARMACOLOGIC AND OTHER THERAPIES THAT REVERSE THESE MODIFICATIONS COULD HAVE POTENTIAL RENOPROTECTIVE EFFECTS FOR DIABETIC NEPHROPATHY. 2010 20 1445 29 DIFFUSE PEDIATRIC-TYPE HIGH-GRADE GLIOMA ARISING IN AN OVARIAN MATURE CYSTIC TERATOMA. IMMATURE NEUROECTODERMAL TISSUE CAN BE FOUND IN THE OVARY AS PART OF AN IMMATURE TERATOMA OR AS PART OF A TERATOMA WITH MALIGNANT NEUROECTODERMAL TRANSFORMATION. SUCH LESIONS MAY CLOSELY RESEMBLE CENTRAL NERVOUS SYSTEM TUMORS, BUT THEIR BIOLOGIC SIMILARITY IS UNCLEAR. WE DESCRIBE AN 18-YR-OLD FEMALE WHO PRESENTED WITH ABDOMINAL PAIN CAUSED BY AN OVARIAN MASS WITH WIDESPREAD METASTASES. HISTOLOGY SHOWED A PRIMITIVE, HIGH-GRADE TUMOR ARISING IN THE BACKGROUND OF A MATURE TERATOMA. THE TUMOR WAS SOX10 POSITIVE, WITH FOCAL EXPRESSION OF GFAP, S100, NSE, AND SYNAPTOPHYSIN. MOLECULAR ANALYSIS DEMONSTRATED CO-AMPLIFICATION OF PDGFRA AND KIT, ALTERATIONS COMMON IN HIGH-GRADE GLIOMAS. BY WHOLE-GENOME METHYLATION PROFILING, IT CLUSTERED INTO THE "DIFFUSE PEDIATRIC-TYPE HIGH-GRADE GLIOMA, RTK1 SUBTYPE, SUBCLASS C" GROUP. DESPITE PROGRESSING THROUGH 2 LINES OF CHEMOTHERAPY WITH WIDESPREAD METASTATIC DISEASE, SHE ACHIEVED AN EXCELLENT RESPONSE TO CHEMOTHERAPY DIRECTED TOWARD AGGRESSIVE GERM CELL TUMORS. THIS CASE EMPHASIZES THE IMPORTANCE OF IMMUNOHISTOCHEMICAL, GENOMIC, AND EPIGENETIC ANALYSES TO ACCURATELY CLASSIFY THESE EXCEEDINGLY RARE TUMORS AND DETERMINE THE OPTIMAL THERAPY. 2023