1 3727 125 INHIBITION OF PANCREATIC ACINAR MITOCHONDRIAL THIAMIN PYROPHOSPHATE UPTAKE BY THE CIGARETTE SMOKE COMPONENT 4-(METHYLNITROSAMINO)-1-(3-PYRIDYL)-1-BUTANONE. THIAMIN IS ESSENTIAL FOR NORMAL METABOLISM IN PANCREATIC ACINAR CELLS (PAC) AND IS OBTAINED FROM THEIR MICROENVIRONMENT THROUGH SPECIFIC PLASMA-MEMBRANE TRANSPORTERS, CONVERTED TO THIAMIN PYROPHOSPHATE (TPP) IN THE CYTOPLASM, FOLLOWED BY UPTAKE OF TPP BY MITOCHONDRIA THROUGH THE MITOCHONDRIAL TPP (MTPP) TRANSPORTER (MTPPT; PRODUCT OF SLC25A19 GENE). TPP IS ESSENTIAL FOR NORMAL MITOCHONDRIAL FUNCTION. WE EXAMINED THE EFFECT OF LONG-TERM/CHRONIC EXPOSURE OF PAC IN VITRO (PANCREATIC ACINAR 266-6 CELLS) AND IN VIVO (WILD-TYPE OR TRANSGENIC MICE CARRYING THE SLC25A19 PROMOTER) OF THE CIGARETTE SMOKE TOXIN, 4-(METHYLNITROSAMINO)-1-(3-PYRIDYL)-1-BUTANONE (NNK), ON THE MTPP UPTAKE PROCESS. OUR IN VITRO AND IN VIVO FINDINGS DEMONSTRATE THAT NNK NEGATIVELY AFFECTS MTPP UPTAKE AND REDUCED EXPRESSION OF MTPPT PROTEIN, MTPPT MRNA, AND HETEROGENOUS NUCLEAR RNA, AS WELL AS SLC25A19 PROMOTER ACTIVITY. THE EFFECT OF NNK ON SLC25A19 TRANSCRIPTION WAS NEITHER MEDIATED BY CHANGES IN EXPRESSION OF TRANSCRIPTIONAL FACTOR NFY-1 (KNOWN TO DRIVE SLC25A19 TRANSCRIPTION), NOR DUE TO CHANGES IN METHYLATION PROFILE OF THE SLC25A19 PROMOTER. RATHER, IT APPEARS TO BE DUE TO CHANGES IN HISTONE MODIFICATIONS THAT INVOLVE SIGNIFICANT DECREASES IN HISTONE H3K4-TRIMETHYLATION AND H3K9-ACETYLATION (ACTIVATION MARKERS). THE EFFECT OF NNK ON MTPPT FUNCTION IS MEDIATED THROUGH THE NONNEURONAL ALPHA7-NICOTINIC ACETYLCHOLINE RECEPTOR (ALPHA7-NACHR), AS INDICATED BY BOTH IN VITRO (USING THE NACHR ANTAGONIST MECAMYLAMINE) AND IN VIVO (USING AN ALPHA7-NACHR(-/-) MOUSE MODEL) STUDIES. THESE FINDINGS DEMONSTRATE THAT CHRONIC EXPOSURE OF PAC TO NNK NEGATIVELY IMPACTS PAC MTPP UPTAKE. THIS EFFECT APPEARS TO BE EXERTED AT THE LEVEL OF SLC25A19 TRANSCRIPTION, INVOLVE EPIGENETIC MECHANISM(S), AND IS MEDIATED THROUGH THE ALPHA7-NACHR. 2016 2 871 77 CHRONIC ALCOHOL EXPOSURE AFFECTS PANCREATIC ACINAR MITOCHONDRIAL THIAMIN PYROPHOSPHATE UPTAKE: STUDIES WITH MOUSE 266-6 CELL LINE AND PRIMARY CELLS. THIAMIN IS ESSENTIAL FOR NORMAL METABOLIC ACTIVITY OF ALL MAMMALIAN CELLS, INCLUDING THOSE OF THE PANCREAS. CELLS OBTAIN THIAMIN FROM THEIR SURROUNDINGS AND ENZYMATICALLY CONVERT IT INTO THIAMIN PYROPHOSPHATE (TPP) IN THE CYTOPLASM; TPP IS THEN TAKEN UP BY MITOCHONDRIA VIA A SPECIFIC CARRIER THE MITOCHONDRIAL TPP TRANSPORTER (MTPPT; PRODUCT OF THE SLC25A19 GENE). CHRONIC ALCOHOL EXPOSURE NEGATIVELY IMPACTS THE HEALTH OF PANCREATIC ACINAR CELLS (PAC), BUT ITS EFFECT ON PHYSIOLOGICAL/MOLECULAR PARAMETERS OF MTPPT IS NOT KNOWN. WE ADDRESSED THIS ISSUE USING MOUSE PANCREATIC ACINAR TUMOR CELL LINE 266-6 AND PRIMARY PAC OF WILD-TYPE AND TRANSGENIC MICE CARRYING THE SLC25A19 PROMOTER THAT WERE FED ALCOHOL CHRONICALLY. CHRONIC ALCOHOL EXPOSURE OF 266-6 CELLS (BUT NOT TO ITS NONOXIDATIVE METABOLITES ETHYL PALMITATE AND ETHYL OLEATE) LED TO A SIGNIFICANT INHIBITION IN MITOCHONDRIAL TPP UPTAKE, WHICH WAS ASSOCIATED WITH A DECREASED EXPRESSION OF MTPPT PROTEIN, MRNA, AND ACTIVITY OF THE SLC25A19 PROMOTER. SIMILARLY, CHRONIC ALCOHOL FEEDING OF MICE LED TO A SIGNIFICANT INHIBITION IN EXPRESSION OF MTPPT PROTEIN, MRNA, HETEROGENEOUS NUCLEAR RNA, AS WELL AS IN ACTIVITY OF SLC25A19 PROMOTER IN PAC. WHILE CHRONIC ALCOHOL EXPOSURE DID NOT AFFECT DNA METHYLATION OF THE SLC25A19 PROMOTER, A SIGNIFICANT DECREASE IN HISTONE H3 EUCHROMATIN MARKERS AND AN INCREASE IN H3 HETEROCHROMATIN MARKER WERE OBSERVED. THESE FINDINGS SHOW, FOR THE FIRST TIME, THAT CHRONIC ALCOHOL EXPOSURE NEGATIVELY IMPACTS PANCREATIC MTPPT, AND THAT THIS EFFECT IS EXERTED, AT LEAST IN PART, AT THE LEVEL OF SLC25A19 TRANSCRIPTION AND APPEARS TO INVOLVE EPIGENETIC MECHANISM(S). 2015 3 6666 59 UPTAKE OF ASCORBIC ACID BY PANCREATIC ACINAR CELLS IS NEGATIVELY IMPACTED BY CHRONIC ALCOHOL EXPOSURE. VITAMIN C (ASCORBIC ACID, AA) IS INDISPENSABLE FOR NORMAL METABOLISM OF ALL MAMMALIAN CELLS INCLUDING PANCREATIC ACINAR CELLS (PACS). PACS OBTAIN AA FROM THEIR SURROUNDINGS VIA TRANSPORT ACROSS THE CELL MEMBRANE. CHRONIC ALCOHOL EXPOSURE NEGATIVELY AFFECTS BODY AA HOMEOSTASIS; IT ALSO INHIBITS UPTAKE OF OTHER MICRONUTRIENTS INTO PACS, BUT ITS EFFECT ON AA UPTAKE IS NOT CLEAR. WE EXAMINED THIS ISSUE USING BOTH IN VITRO (266-6 CELLS) AND IN VIVO (MICE) MODELS OF CHRONIC ALCOHOL EXPOSURE. FIRST, WE DETERMINED THE RELATIVE EXPRESSION OF THE AA TRANSPORTERS 1 AND 2 [I.E., SODIUM-DEPENDENT VITAMIN C TRANSPORTER-1 (SVCT-1) AND SVCT-2] IN MOUSE AND HUMAN PACS AND FOUND SVCT-2 TO BE THE PREDOMINANT TRANSPORTER. CHRONIC EXPOSURE OF 266-6 CELLS TO ALCOHOL SIGNIFICANTLY INHIBITED AA UPTAKE AND CAUSED A MARKED REDUCTION IN SVCT-2 EXPRESSION AT THE PROTEIN, MRNA, AND HETEROGENEOUS NUCLEAR RNA (HNRNA) LEVELS. SIMILARLY, CHRONIC ALCOHOL FEEDING OF MICE SIGNIFICANTLY INHIBITED AA UPTAKE AND CAUSED A MARKED REDUCTION IN LEVEL OF EXPRESSION OF THE SVCT-2 PROTEIN, MRNA, AND HNRNA. THESE FINDINGS SUGGEST POSSIBLE INVOLVEMENT OF TRANSCRIPTIONAL MECHANISM(S) IN MEDIATING CHRONIC ALCOHOL EFFECT ON AA UPTAKE BY PACS. WE ALSO OBSERVED SIGNIFICANT EPIGENETIC CHANGES (HISTONE MODIFICATIONS) IN THE SLC23A2 GENE (REDUCTION IN H3K4ME3 LEVEL AND AN INCREASE IN H3K27ME3 LEVEL) IN THE ALCOHOL-EXPOSED 266-6 CELLS. THESE FINDINGS SHOW THAT CHRONIC ALCOHOL EXPOSURE INHIBITS PAC AA UPTAKE AND THAT THE EFFECT IS MEDIATED, IN PART, AT THE LEVEL OF TRANSCRIPTION OF THE SLC23A2 GENE AND MAY INVOLVE EPIGENETIC MECHANISM(S). 2016 4 873 58 CHRONIC ALCOHOL EXPOSURE INHIBITS BIOTIN UPTAKE BY PANCREATIC ACINAR CELLS: POSSIBLE INVOLVEMENT OF EPIGENETIC MECHANISMS. CHRONIC EXPOSURE TO ALCOHOL AFFECTS DIFFERENT PHYSIOLOGICAL ASPECTS OF PANCREATIC ACINAR CELLS (PAC), BUT ITS EFFECT ON THE UPTAKE PROCESS OF BIOTIN IS NOT KNOWN. WE ADDRESSED THIS ISSUE USING MOUSE-DERIVED PANCREATIC ACINAR 266-6 CELLS CHRONICALLY EXPOSED TO ALCOHOL AND WILD-TYPE AND TRANSGENIC MICE (CARRYING THE HUMAN SLC5A6 5'-PROMOTER) FED ALCOHOL CHRONICALLY. FIRST WE ESTABLISHED THAT BIOTIN UPTAKE BY PAC IS NA(+) DEPENDENT AND CARRIER MEDIATED AND INVOLVES SODIUM-DEPENDENT MULTIVITAMIN TRANSPORTER (SMVT). CHRONIC EXPOSURE OF 266-6 CELLS TO ALCOHOL LED TO A SIGNIFICANT INHIBITION IN BIOTIN UPTAKE, EXPRESSION OF SMVT PROTEIN, AND MRNA AS WELL AS IN THE ACTIVITY OF THE SLC5A6 PROMOTER. SIMILARLY, CHRONIC ALCOHOL FEEDING OF WILD-TYPE AND TRANSGENIC MICE CARRYING THE SLC5A6 PROMOTER LED TO A SIGNIFICANT INHIBITION IN BIOTIN UPTAKE BY PAC, AS WELL AS IN THE EXPRESSION OF SMVT PROTEIN AND MRNA AND THE ACTIVITY OF THE SLC5A6 PROMOTERS EXPRESSED IN THE TRANSGENIC MICE. WE ALSO FOUND THAT CHRONIC ALCOHOL FEEDING OF MICE IS ASSOCIATED WITH A SIGNIFICANT INCREASE IN THE METHYLATION STATUS OF CPG ISLANDS PREDICTED TO BE IN THE MOUSE SLC5A6 PROMOTERS AND A DECREASE IN THE LEVEL OF EXPRESSION OF TRANSCRIPTION FACTOR KLF-4, WHICH PLAYS AN IMPORTANT ROLE IN REGULATING SLC5A6 PROMOTER ACTIVITY. THESE RESULTS DEMONSTRATE, FOR THE FIRST TIME, THAT CHRONIC ALCOHOL EXPOSURE NEGATIVELY IMPACTS BIOTIN UPTAKE IN PAC AND THAT THIS EFFECT IS EXERTED (AT LEAST IN PART) AT THE LEVEL OF TRANSCRIPTION OF THE SLC5A6 GENE AND MAY INVOLVE EPIGENETIC/MOLECULAR MECHANISMS. 2014 5 2395 31 EPIGENETIC REPROGRAMMING IN MIST1(-/-) MICE PREDICTS THE MOLECULAR RESPONSE TO CERULEIN-INDUCED PANCREATITIS. GENE EXPRESSION IS AFFECTED BY MODIFICATIONS TO HISTONE CORE PROTEINS WITHIN CHROMATIN. CHANGES IN THESE MODIFICATIONS, OR EPIGENETIC REPROGRAMMING, CAN DICTATE CELL FATE AND PROMOTE SUSCEPTIBILITY TO DISEASE. THE GOAL OF THIS STUDY WAS TO DETERMINE THE EXTENT OF EPIGENETIC REPROGRAMMING IN RESPONSE TO CHRONIC STRESS THAT OCCURS FOLLOWING ABLATION OF MIST1 (MIST1(-/-) ), WHICH IS REPRESSED IN PANCREATIC DISEASE. CHROMATIN IMMUNOPRECIPITATION FOR TRIMETHYLATION OF LYSINE RESIDUE 4 ON HISTONE 3 (H3K4ME3) IN PURIFIED ACINAR CELLS FROM WILD TYPE AND MIST1(-/-) MICE WAS FOLLOWED BY NEXT GENERATION SEQUENCING (CHIP-SEQ) OR CHIP-QPCR. H3K4ME3-ENRICHED GENES WERE ASSESSED FOR EXPRESSION BY QRT-PCR IN PANCREATIC TISSUE BEFORE AND AFTER INDUCTION OF CERULEIN-INDUCED PANCREATITIS. WHILE MOST OF H3K4ME3-ENRICHMENT IS RESTRICTED TO TRANSCRIPTIONAL START SITES, >25% OF ENRICHMENT SITES ARE FOUND WITHIN, DOWNSTREAM OR BETWEEN ANNOTATED GENES. LESS THAN 10% OF THESE SITES WERE ALTERED IN MIST1(-/-) ACINI, WITH MOST CHANGES IN H3K4ME3 ENRICHMENT NOT REFLECTING ALTERED GENE EXPRESSION. INGENUITY PATHWAY ANALYSIS OF GENES DIFFERENTIALLY-ENRICHED FOR H3K4ME3 REVEALED AN ASSOCIATION WITH PANCREATITIS AND PANCREATIC DUCTAL ADENOCARCINOMA IN MIST1(-/-) TISSUE. MOST OF THESE GENES WERE NOT DIFFERENTIALLY EXPRESSED BUT SEVERAL WERE READILY INDUCED BY ACUTE EXPERIMENTAL PANCREATITIS, WITH SIGNIFICANTLY INCREASED EXPRESSION IN MIST1(-/-) TISSUE RELATIVE TO WILD TYPE MICE. WE SUGGEST THAT THE CHRONIC CELL STRESS OBSERVED IN THE ABSENCE OF MIST1 RESULTS IN EPIGENETIC REPROGRAMMING OF GENES INVOLVED IN PROMOTING PANCREATITIS TO A POISED STATE, THEREBY INCREASING THE SENSITIVITY TO EVENTS THAT PROMOTE DISEASE. 2014 6 2032 31 EPIGENETIC CHANGES IN P21 EXPRESSION IN RENAL CELLS AFTER EXPOSURE TO BROMATE. THIS STUDY TESTED THE HYPOTHESIS THAT BROMATE (KBRO3)-INDUCED RENAL CELL DEATH IS MEDIATED BY EPIGENETIC MECHANISMS. GLOBAL DNA METHYLATION, AS ASSESSED BY 5-METHYLCYTOSINE STAINING, WAS NOT CHANGED IN NORMAL RAT KIDNEY CELLS TREATED WITH ACUTE CYTOTOXIC DOSES OF KBRO3 (100 AND 200 PPM), AS COMPARED WITH CONTROLS. HOWEVER, KBRO3 TREATMENT DID INCREASE P38, P53 AND HISTONE 2AX (H2AX) PHOSPHORYLATION, AND P21 EXPRESSION. TREATMENT OF CELLS WITH INHIBITORS OF DNA METHYLTRANSFERASE (5-AZACYTIDINE OR 5-AZA) AND HISTONE DEACETYLASE (TRICHOSTATIN A OR TSA) IN ADDITION TO KBRO3 INCREASED CYTOTOXICITY, AS COMPARED WITH CELLS EXPOSED TO KBRO3 ALONE. 5-AZA AND TSA CO-TREATMENT DID NOT ALTER P38 OR P53 PHOSPHORYLATION, BUT SLIGHTLY DECREASED H2AX PHOSPHORYLATION AND SIGNIFICANTLY DECREASED P21 EXPRESSION. WE ALSO ASSESSED EPIGENETIC CHANGES IN CELLS TREATED UNDER SUB-CHRONIC CONDITIONS WITH ENVIRONMENTALLY RELEVANT CONCENTRATIONS OF KBRO3. UNDER THESE CONDITIONS (0-10PPM KBRO3 FOR UP TO 18 DAYS), WE DETECTED NO INCREASES IN CELL DEATH OR DNA DAMAGE. IN CONTRAST, SLIGHT ALTERATIONS WERE DETECTED IN THE PHOSPHORYLATION OF H2AX, P38, AND P53. SUB-CHRONIC LOW-DOSE KBRO3 TREATMENT ALSO INDUCED A BIPHASIC RESPONSE IN P21 EXPRESSION, WITH LOWER CONCENTRATIONS INCREASING EXPRESSION, BUT HIGHER CONCENTRATIONS DECREASING EXPRESSION. METHYLATION-SPECIFIC PCR DEMONSTRATED THAT SUB-CHRONIC KBRO3 TREATMENT ALTERED THE METHYLATION OF CYTOSINE BASES IN THE P21 GENE, AS COMPARED WITH CONTROLS, CORRELATING TO ALTERATIONS IN P21 PROTEIN EXPRESSION. COLLECTIVELY, THESE DATA SHOW THE NOVEL FINDING THAT KBRO3-INDUCED RENAL CELL DEATH IS ALTERED BY INHIBITORS OF EPIGENETIC MODIFYING ENZYMES AND THAT KBRO3 ITSELF INDUCES EPIGENETIC CHANGES IN THE P21 GENE. 2014 7 4499 29 MORPHINE WITHDRAWAL PRODUCES ERK-DEPENDENT AND ERK-INDEPENDENT EPIGENETIC MARKS IN NEURONS OF THE NUCLEUS ACCUMBENS AND LATERAL SEPTUM. EPIGENETIC CHANGES SUCH AS COVALENT MODIFICATIONS OF HISTONE PROTEINS REPRESENT COMPLEX MOLECULAR SIGNATURES THAT PROVIDE A CELLULAR MEMORY OF PREVIOUSLY EXPERIENCED STIMULI WITHOUT IRREVERSIBLE CHANGES OF THE GENETIC CODE. IN THIS STUDY WE SHOW THAT NEW GENE EXPRESSION INDUCED IN VIVO BY MORPHINE WITHDRAWAL OCCURS WITH CONCOMITANT EPIGENETIC MODIFICATIONS IN BRAIN REGIONS CRITICALLY INVOLVED IN DRUG-DEPENDENT BEHAVIORS. WE FOUND THAT NALOXONE-PRECIPITATED WITHDRAWAL, BUT NOT CHRONIC MORPHINE ADMINISTRATION, CAUSED A STRONG INDUCTION OF PHOSPHO-HISTONE H3 IMMUNOREACTIVITY IN THE NUCLEUS ACCUMBENS (NAC) SHELL/CORE AND IN THE LATERAL SEPTUM (LS), A CHANGE THAT WAS ACCOMPANIED BY AUGMENTED H3 ACETYLATION (LYS14) IN NEURONS OF THE NAC SHELL. MORPHINE WITHDRAWAL INDUCED THE PHOSPHORYLATION OF THE EPIGENETIC FACTOR METHYL-CPG-BINDING PROTEIN 2 (MECP2) IN SER421 BOTH IN THE LS AND THE NAC SHELL. THESE EPIGENETIC CHANGES WERE ACCOMPANIED BY THE ACTIVATION OF MEMBERS OF THE ERK PATHWAY AS WELL AS INCREASED EXPRESSION OF THE IMMEDIATE EARLY GENES (IEG) C-FOS AND ACTIVITY-REGULATED CYTOSKELETON-ASSOCIATED PROTEIN (ARC/ARG3.1). USING A PHARMACOLOGICAL APPROACH, WE FOUND THAT H3 PHOSPHORYLATION AND IEG EXPRESSION WERE PARTIALLY DEPENDENT ON ERK ACTIVATION, WHILE MECP2 PHOSPHORYLATION WAS FULLY ERK-INDEPENDENT. THESE FINDINGS PROVIDE NEW IMPORTANT INFORMATION ON THE ROLE OF THE ERK PATHWAY IN THE REGULATION OF EPIGENETIC MARKS AND GENE EXPRESSION THAT MAY CONCUR TO REGULATE IN VIVO THE CELLULAR CHANGES UNDERLYING THE ONSET OF THE OPIOID WITHDRAWAL SYNDROME. 2013 8 2030 31 EPIGENETIC CHANGES IN INFLAMMATORY GENES AND THE PROTECTIVE EFFECT OF COOKED RHUBARB ON PANCREATIC TISSUE OF RATS WITH CHRONIC ALCOHOL EXPOSURE. CHRONIC ALCOHOL CONSUMPTION, WHICH IS OBSERVED WORLDWIDE, CAN DAMAGE PANCREATIC TISSUE AND PROMOTE PANCREATITIS. RHUBARB IS A WIDELY USED TRADITIONAL CHINESE HERBAL MEDICINE FOR TREATING PANCREATITIS IN CHINA. HOWEVER, FEW PHARMACOLOGICAL STUDIES HAVE INVESTIGATED ITS EPIGENETIC REGULATION. IN THIS STUDY, WE INVESTIGATED WHETHER CHRONIC EXPOSURE TO ALCOHOL CAN ALTER INFLAMMATORY GENE EXPRESSION AND THE EPIGENETIC REGULATION EFFECT OF COOKED RHUBARB IN THE PANCREATIC TISSUE OF RATS. FIRST, CHANGES IN INFLAMMATORY CYTOKINE DNA METHYLATION (IL-10, IL-1ALPHA, TNF-ALPHA, NF-KAPPAB AND TGF-BETA) WERE DETECTED IN PANCREATIC TISSUE OF SPRAGUE-DAWLEY RATS WITH VARYING ALCOHOL EXPOSURE TIMES (4, 6, 8, OR 12 WEEKS), AND THEN WITH VARYING DOSES OF COOKED RHUBARB TREATMENT (3, 6, OR 12 G/DAY). DNA METHYLATION LEVELS, RELATED RNA CONCENTRATIONS AND PROTEIN EXPRESSION OF SPECIFIC INFLAMMATORY CYTOKINES, AND HISTOPATHOLOGICAL SCORE WERE ANALYSED IN PANCREATIC TISSUE OF SPRAGUE-DAWLEY RATS. THE RESULTS SHOWED THAT CHRONIC ALCOHOL EXPOSURE (8 WEEKS) REDUCED THE LEVEL OF IL-1ALPHA DNA METHYLATION AND INCREASED ITS PROTEIN EXPRESSION IN ACINAR CELLS (P < 0.05). IN THE ACINAR CELLS, THE LEVEL OF IL-10 DNA METHYLATION INCREASED, RESULTING IN A REDUCTION OF PROTEIN EXPRESSION (P < 0.05). SIMULTANEOUSLY, CHRONIC ALCOHOL EXPOSURE INCREASED THE PATHOLOGICAL DAMAGE TO THE PANCREAS (P < 0.05). FINALLY, COOKED RHUBARB TREATMENT (3 G/KG/DAY) EFFECTIVELY ALLEVIATED THESE CHANGES IN PANCREATIC TISSUE FROM CHRONIC ALCOHOL EXPOSURE (P < 0.05). THESE RESULTS INDICATE THAT CHRONIC EXPOSURE TO ALCOHOL LEADS TO CHANGES IN DNA METHYLATION AND PROTEIN EXPRESSION OF INFLAMMATORY GENES, AND COOKED RHUBARB MAY HAVE A PROTECTIVE EFFECT ON THE PANCREATIC TISSUE OF RATS. 2022 9 895 33 CHRONIC ETHANOL-MEDIATED HEPATOCYTE APOPTOSIS LINKS TO DECREASED TET1 AND 5-HYDROXYMETHYLCYTOSINE FORMATION. THE 5-HYDROXYMETHYLCYTOSINE (5HMC) IS A NEWLY IDENTIFIED EPIGENETIC MODIFICATION THOUGHT TO BE REGULATED BY THE TET FAMILY OF PROTEINS. LITTLE INFORMATION IS AVAILABLE ABOUT HOW ETHANOL CONSUMPTION MAY MODULATE 5HMC FORMATION AND ALCOHOLIC LIVER DISEASE (ALD) PROGRESSION. A RAT ALD MODEL WAS USED TO STUDY 5HMC IN RELATIONSHIP TO HEPATOCYTE APOPTOSIS. HUMAN ALD LIVER SAMPLES WERE ALSO USED TO VALIDATE THESE FINDINGS. IT WAS FOUND THAT CHRONIC ETHANOL FEEDING SIGNIFICANTLY REDUCED 5HMC FORMATION IN A RAT ALD MODEL. THERE WERE NO SIGNIFICANT CHANGES IN TET2 AND TET3 BETWEEN THE CONTROL- AND ETHANOL-FED ANIMALS. IN CONTRAST, METHYLCYTOSINE DIOXYGENASE TET1 (TET1) EXPRESSION WAS SUBSTANTIALLY REDUCED IN THE ETHANOL-FED RATS AND WAS ACCOMPANIED BY INCREASED HEPATOCYTE APOPTOSIS. SIMILARLY, KNOCKDOWN OF TET1 IN HUMAN HEPATOCYTE-LIKE CELLS ALSO SIGNIFICANTLY PROMOTED APOPTOSIS. DOWN-REGULATION OF TET1 RESULTED IN ELEVATED EXPRESSION OF THE DNA DAMAGE MARKER, SUGGESTING A ROLE FOR 5HMC IN HEPATOCYTE DNA DAMAGE AS WELL. MECHANISTIC STUDIES REVEALED THAT INHIBITION OF TET1 PROMOTED APOPTOTIC GENE EXPRESSION. SIMILARLY, TARGETING TET1 ACTIVITY BY REMOVING COSUBSTRATE PROMOTED APOPTOSIS AND DNA DAMAGE. FURTHERMORE, TREATMENT WITH 5-AZACITIDINE SIGNIFICANTLY MIMICS THESE EFFECTS, SUGGESTING THAT CHRONIC ETHANOL CONSUMPTION PROMOTES HEPATOCYTE APOPTOSIS AND DNA DAMAGE BY DIMINISHING TET1-MEDIATED 5HMC FORMATION AND DNA METHYLATION. IN SUMMARY, THE CURRENT STUDY PROVIDES A NOVEL MOLECULAR INSIGHT THAT TET1-MEDIATED 5HMC IS INVOLVED IN HEPATOCYTE APOPTOSIS IN ALD PROGRESSION.-JI, C., NAGAOKA, K., ZOU, J., CASULLI, S., LU, S., CAO, K. Y., ZHANG, H., IWAGAMI, Y., CARLSON, R. I., BROOKS, K., LAWRENCE, J., MUELLER, W., WANDS, J. R., HUANG, C.-K. CHRONIC ETHANOL-MEDIATED HEPATOCYTE APOPTOSIS LINKS TO DECREASED TET1 AND 5-HYDROXYMETHYLCYTOSINE FORMATION. 2019 10 6294 25 THE PROINFLAMMATORY CYTOKINE TNFALPHA INDUCES DNA DEMETHYLATION-DEPENDENT AND -INDEPENDENT ACTIVATION OF INTERLEUKIN-32 EXPRESSION. IL-32 IS A CYTOKINE INVOLVED IN PROINFLAMMATORY IMMUNE RESPONSES TO BACTERIAL AND VIRAL INFECTIONS. HOWEVER, THE ROLE OF EPIGENETIC EVENTS IN THE REGULATION OF IL-32 GENE EXPRESSION IS UNDERSTUDIED. HERE WE SHOW THAT IL-32 IS REPRESSED BY DNA METHYLATION IN HEK293 CELLS. USING CHIP SEQUENCING, LOCUS-SPECIFIC METHYLATION ANALYSIS, CRISPR/CAS9-MEDIATED GENOME EDITING, AND RT-QPCR (QUANTITATIVE RT-PCR) AND IMMUNOBLOT ASSAYS, WE FOUND THAT SHORT-TERM TREATMENT (A FEW HOURS) WITH THE PROINFLAMMATORY CYTOKINE TUMOR NECROSIS FACTOR ALPHA (TNFALPHA) ACTIVATES IL-32 IN A DNA DEMETHYLATION-INDEPENDENT MANNER. IN CONTRAST, PROLONGED TNFALPHA TREATMENT (SEVERAL DAYS) INDUCED DNA DEMETHYLATION AT THE PROMOTER AND A CPG ISLAND IN THE IL-32 GENE IN A TET (TEN-ELEVEN TRANSLOCATION) FAMILY ENZYME- AND NF-KAPPAB-DEPENDENT MANNER. NOTABLY, THE HYPOMETHYLATION STATUS OF TRANSCRIPTIONAL REGULATORY ELEMENTS IN IL-32 WAS MAINTAINED FOR A LONG TIME (SEVERAL WEEKS), CAUSING ELEVATED IL-32 EXPRESSION EVEN IN THE ABSENCE OF TNFALPHA. CONSIDERING THAT IL-32 CAN, IN TURN, INDUCE TNFALPHA EXPRESSION, WE SPECULATE THAT SUCH FEEDFORWARD EVENTS MAY CONTRIBUTE TO THE TRANSITION FROM AN ACUTE INFLAMMATORY RESPONSE TO CHRONIC INFLAMMATION. 2019 11 3974 31 LONG-TERM CADMIUM EXPOSURE IMPAIRS COGNITIVE FUNCTION BY ACTIVATING LNC-GM10532/M6A/FIS1 AXIS-MEDIATED MITOCHONDRIAL FISSION AND DYSFUNCTION. CADMIUM (CD), A UBIQUITOUS ENVIRONMENTAL CONTAMINANT, IS DEEMED A POSSIBLE AETIOLOGICAL CAUSE OF COGNITIVE DISORDERS IN HUMANS. NEVERTHELESS, THE EXACT MECHANISM BY WHICH CHRONIC EXPOSURE TO CD CAUSES NEUROTOXICITY IS NOT FULLY UNDERSTOOD. IN THIS STUDY, MOUSE NEUROBLASTOMA CELLS (NEURO-2A CELLS) AND PRIMARY HIPPOCAMPAL NEURONS WERE EXPOSED TO LOW-DOSE (1, 2, AND 4 MUM FOR NEURO-2A CELLS OR 0.5, 1, AND 1.5 MUM FOR HIPPOCAMPAL NEURONS) CADMIUM CHLORIDE (CDCL(2)) FOR 72 H (H), AND MALE MICE (C57BL/6J, 8 WEEKS) WERE ORALLY ADMINISTERED CDCL(2) (0.6 MG/L, APPROXIMATELY EQUAL TO 2.58 MUG/KG.BW/D) FOR 6 MONTHS TO INVESTIGATE THE EFFECTS AND MECHANISM OF CHRONIC CD-INDUCED NEUROTOXICITY. HERE, CHRONIC EXPOSURE TO CD IMPAIRED MITOCHONDRIAL FUNCTION BY PROMOTING EXCESS REACTIVE OXYGEN SPECIES (ROS) PRODUCTION, ALTERING MITOCHONDRIAL MEMBRANE POTENTIAL (DELTAPSIM) AND REDUCING ADENOSINE TRIPHOSPHATE (ATP) CONTENT, CONTRIBUTING TO NEURONAL CELL DEATH. SPECIFICALLY, MICROARRAY ANALYSIS REVEALED THAT THE LONG NONCODING RNA GM10532 (LNC-GM10532) WAS MOST HIGHLY EXPRESSED IN NEURO-2A CELLS EXPOSED TO 4 MUM CDCL(2) FOR 72 H COMPARED WITH CONTROLS, AND INHIBITION OF LNC-GM10532 SIGNIFICANTLY ANTAGONIZED CDCL(2)-INDUCED MITOCHONDRIAL DYSFUNCTION AND NEUROTOXICITY. MECHANISTICALLY, LNC-GM10532 INCREASED FISSION 1 (FIS1) EXPRESSION AND MITOCHONDRIAL FISSION BY RECRUITING THE M6A WRITER METHYLTRANSFERASE-LIKE 14 (METTL14) AND ENHANCING M6A MODIFICATION OF FIS1 MRNA. MOREOVER, LNC-GM10532 WAS ALSO REQUIRED FOR CHRONIC CD-INDUCED MITOCHONDRIAL DYSFUNCTION AND MEMORY DEFICITS IN A RODENT MODEL. THEREFORE, DATA OF THIS STUDY REVEAL A NEW EPIGENETIC MECHANISM OF CHRONIC CD NEUROTOXICITY. 2023 12 2673 35 ETHANOL-INDUCED MODULATION OF GPR55 EXPRESSION IN HUMAN MONOCYTE-DERIVED DENDRITIC CELLS IS ACCOMPANIED BY H4K12 ACETYLATION. INFLAMMATION SUPPORTS THE PROGRESSION OF ALCOHOL-RELATED ORGAN INJURY. RECENT RESEARCH FINDINGS HAVE LINKED ETHANOL EXPOSURE TO CHANGES IN HISTONE ACETYLATION AND DEACETYLATION IN THE BRAIN AND IN PERIPHERAL TISSUES, LEADING TO ETHANOL-DEPENDENCE RELATED DAMAGE. ONE OF THE MECHANISMS THAT HAS BEEN SHOWN TO PLAY A MAJOR ROLE DURING INFLAMMATION IS THE CANNABINOID SYSTEM. PREVIOUS RESEARCH HAS DEMONSTRATED THAT ETHANOL CAN MODULATE CANNABINOID RECEPTORS' FUNCTIONS. OUR LAB HAS SHOWN THAT THE G PROTEIN-COUPLED RECEPTOR (GPR55), A NOVEL CANNABINOID RECEPTOR, IS UPREGULATED IN BINGE DRINKERS AND IN CELLS TREATED ACUTELY WITH ETHANOL. ADDITIONALLY, OUR GROUP HAS ALSO UNCOVERED THAT CHRONIC ETHANOL EXPOSURE LEADS TO AN INCREASE IN HISTONE MODIFICATIONS, SUCH AS ACETYLATION. HOWEVER, THE REGULATORY MECHANISM OF GPR55 WITHIN THE IMMUNE SYSTEM UNDER THE INFLUENCE OF ETHANOL IS POORLY UNDERSTOOD. SINCE CHANGES IN HISTONE MODIFICATIONS MIGHT LEAD TO CHANGES IN GENE EXPRESSION, WE HYPOTHESIZE THAT THE MECHANISM OF ETHANOL-INDUCED UPREGULATION OF GPR55 IS LINKED TO EPIGENETIC CHANGES ON HISTONE PROTEINS. TAKING INTO ACCOUNT PREVIOUS FINDINGS FROM OUR LAB, THE GOAL OF THE PRESENT STUDY WAS TO DETERMINE WHETHER THERE IS ANY RELEVANT ASSOCIATION BETWEEN HISTONE HYPERACETYLATION AND THE REGULATION OF THE NOVEL CANNABINOID RECEPTOR GPR55 IN MONOCYTE-DERIVED DENDRITIC CELLS (MDDCS) OF HUMAN ORIGIN TREATED ACUTELY WITH ETHANOL. THEREFORE, MONOCYTES WERE ISOLATED FROM BUFFY COATS AND ALLOWED TO DIFFERENTIATE INTO MDDCS. THE CELLS WERE TREATED WITH ETHANOL FOR 24 H, HARVESTED, FIXED, AND STAINED WITH ANTIBODIES AGAINST GPR55. AS EXPECTED, BASED ON PREVIOUS FINDINGS, CONFOCAL MICROSCOPY SHOWED THAT ETHANOL EXPOSURE INCREASES GPR55 EXPRESSION. IN ORDER TO DEMONSTRATE THE CORRELATION BETWEEN HISTONE ACETYLATION AND GPR55 EXPRESSION REGULATION, THE CELLS WERE TREATED WITH ETHANOL, HARVESTED, AND THEN THE CHROMATIN WAS EXTRACTED AND FRACTIONATED FOR CHROMATIN IMMUNOPRECIPITATION (CHIP) ASSAY, FOLLOWED BY REAL-TIME QPCR FOR THE ANALYSIS OF DNA FRAGMENTS. THE RESULTS SHOWED AN ENRICHMENT OF THE HISTONE MODIFICATION H4K12AC IN THE GPR55 GENE OF MDDCS TREATED WITH ETHANOL. FURTHERMORE, SIRNA AGAINST THE HISTONE ACETYLTRANSFERASE TIP60 (RESPONSIBLE FOR THE ACETYLATION OF H4K12) RESULTED IN A DOWNREGULATION OF GPR55. IN CONJUNCTION, THESE RESULTS INDICATE THAT IN THE PRESENCE OF ETHANOL, THE UPREGULATION OF GPR55 EXPRESSION IS ACCOMPANIED BY H4K12 ACETYLATION, WHICH MIGHT HAVE A SIGNIFICANT EFFECT IN THE ABILITY OF THIS INNATE IMMUNE SYSTEM'S CELLS TO COPE WITH CELLULAR STRESS INDUCED BY ETHANOL. HOWEVER, THE CAUSALITY OF ETHANOL REGULATION OF H4K12AC IN GPR55 EXPRESSION CHANGES STILL LACKS FURTHER ELUCIDATION; THEREFORE, ADDITIONAL EXPERIMENTAL APPROACHES TO CONFIRM A SIGNIFICANT CAUSALITY BETWEEN H4K12 ACETYLATION AND ETHANOL REGULATION OF GPR55 ARE CURRENTLY UNDERGOING IN OUR LAB. 2018 13 6411 34 THE SITE SPECIFIC DEMETHYLATION IN THE 5'-REGULATORY AREA OF NMDA RECEPTOR 2B SUBUNIT GENE ASSOCIATED WITH CIE-INDUCED UP-REGULATION OF TRANSCRIPTION. BACKGROUND: THE NMDA RECEPTOR REPRESENTS A PARTICULARLY IMPORTANT SITE OF ETHANOL ACTION IN THE CNS. WE RECENTLY REPORTED THAT NMDA RECEPTOR 2B (NR2B) GENE EXPRESSION WAS PERSISTENTLY UP-REGULATED FOLLOWING CHRONIC INTERMITTENT ETHANOL (CIE) TREATMENT. INCREASING EVIDENCE THAT EPIGENETIC MECHANISMS ARE INVOLVED IN DYNAMIC AND LONG-LASTING REGULATION OF GENE EXPRESSION IN MULTIPLE NEUROADAPTIVE PROCESSES PROMPTED US TO INVESTIGATE THE ROLE OF DNA METHYLATION IN MEDIATING CIE-INDUCED UP-REGULATION OF NR2B GENE TRANSCRIPTION. TO DISSECT THE CHANGES OF DNA METHYLATION IN THE NR2B GENE, WE HAVE SCREENED A LARGE NUMBER OF CPG SITES WITHIN ITS 5'-REGULATORY AREA FOLLOWING CIE TREATMENT. METHODS: PRIMARY CORTICAL CULTURED NEURONS WERE SUBJECTED TO ETHANOL TREATMENT IN A CIE PARADIGM. BISULFITE CONVERSION FOLLOWED BY PYROSEQUENCING WAS USED FOR QUANTITATIVE MEASUREMENT AND ANALYSIS OF CPG METHYLATION STATUS WITHIN THE 5'-REGULATORY AREA OF THE NR2B GENE; CHROMATIN IMMUNOPRECIPITATION (CHIP) ASSAY WAS USED TO EXAMINE DNA LEVELS ASSOCIATED WITH METHYLATION AND TRANSCRIPTION FACTOR BINDING. ELECTROPHORETIC MOBILITY SHIFT ASSAY (EMSA) AND IN VITRO DNA METHYLATION ASSAYS WERE PERFORMED TO DETERMINE THE DIRECT IMPACT OF DNA METHYLATION ON THE INTERACTION BETWEEN DNA AND TRANSCRIPTION FACTOR AND PROMOTER ACTIVITY. RESULTS: ANALYSIS OF INDIVIDUAL CPG METHYLATION SITES WITHIN THE NR2B 5'REGULATORY AREA REVEALED THREE REGIONS WITH CLUSTERS OF SITE-SPECIFIC CPG DEMETHYLATION FOLLOWING CIE TREATMENT AND WITHDRAWAL. THIS WAS CONFIRMED BY CHIP SHOWING SIMILAR DECREASES OF METHYLATED DNA IN THE SAME REGIONS. THE CIE-INDUCED DEMETHYLATION IS CHARACTERIZED BY BEING LOCATED NEAR CERTAIN TRANSCRIPTION FACTOR BINDING SEQUENCES, AP-1 AND CRE, AND OCCURRED DURING TREATMENT AS WELL AS AFTER ETHANOL WITHDRAWAL. FURTHERMORE, THE INCREASE IN VITRO OF METHYLATED DNA DECREASED TRANSCRIPTION FACTOR BINDING ACTIVITY AND PROMOTER ACTIVITY. AN ADDITIONAL CHIP ASSAY INDICATED THAT THE CIE-INDUCED DNA DEMETHYLATION IS ACCOMPANIED BY INCREASED OCCUPATION BY TRANSCRIPTION FACTORS. CONCLUSIONS: THESE RESULTS SUGGEST AN IMPORTANT ROLE OF DNA DEMETHYLATION IN MEDIATING CIE-INDUCED NR2B GENE UP-REGULATION, THUS IMPLICATING A NOVEL MOLECULAR SITE OF ALCOHOL ACTION. 2010 14 3306 30 HIGH-PHOSPHATE-INDUCED CALCIFICATION IS RELATED TO SM22ALPHA PROMOTER METHYLATION IN VASCULAR SMOOTH MUSCLE CELLS. HYPERPHOSPHATEMIA IS CLOSELY RELATED TO VASCULAR CALCIFICATION IN PATIENTS WITH CHRONIC KIDNEY DISEASE. VASCULAR SMOOTH MUSCLE CELLS (VSMCS) EXPOSED TO HIGH PHOSPHATE CONCENTRATIONS IN VITRO UNDERGO PHENOTYPIC TRANSITION TO OSTEOBLAST-LIKE CELLS. MECHANISMS UNDERLYING THIS TRANSDIFFERENTIATION ARE NOT CLEAR. IN THIS STUDY WE USED TWO IN VITRO MODELS, HUMAN AORTIC SMOOTH MUSCLE CELLS AND RAT AORTIC RINGS, TO INVESTIGATE THE PHENOTYPIC TRANSITION OF VSMCS INDUCED BY HIGH PHOSPHATE. WE FOUND THAT HIGH PHOSPHATE CONCENTRATION (3.3 MMOL/L) IN THE MEDIUM WAS ASSOCIATED WITH INCREASED DNA METHYLTRANSFERASE ACTIVITY AND METHYLATION OF THE PROMOTER REGION OF SM22ALPHA. THIS WAS ACCOMPANIED BY LOSS OF THE SMOOTH MUSCLE CELL-SPECIFIC PROTEIN SM22ALPHA, GAIN OF THE OSTEOBLAST TRANSCRIPTION FACTOR CBFA1, AND INCREASED ALKALINE PHOSPHATASE ACTIVITY WITH THE SUBSEQUENT IN VITRO CALCIFICATION. THE ADDITION OF A DEMETHYLATING AGENT (PROCAINE) TO THE HIGH-PHOSPHATE MEDIUM REDUCED DNA METHYLTRANSFERASE ACTIVITY AND PREVENTED METHYLATION OF THE SM22ALPHA PROMOTER, WHICH WAS ACCOMPANIED BY AN INCREASE IN SM22ALPHA EXPRESSION AND LESS CALCIFICATION. ADDITIONALLY, DOWNREGULATION OF SM22ALPHA, EITHER BY SIRNA OR BY A METHYL GROUP DONOR (S-ADENOSYL METHIONINE), RESULTED IN OVEREXPRESSION OF CBFA1. IN CONCLUSION, WE DEMONSTRATE THAT METHYLATION OF SM22ALPHA PROMOTER IS AN IMPORTANT EVENT IN VASCULAR SMOOTH MUSCLE CELL CALCIFICATION AND THAT HIGH PHOSPHATE INDUCES THIS EPIGENETIC MODIFICATION. THESE FINDINGS UNCOVER A NEW INSIGHT INTO MECHANISMS BY WHICH HIGH PHOSPHATE CONCENTRATION PROMOTES VASCULAR CALCIFICATION. 2010 15 3813 38 INTRAUTERINE GROWTH RESTRICTION INHIBITS EXPRESSION OF EUKARYOTIC ELONGATION FACTOR 2 KINASE, A REGULATOR OF PROTEIN TRANSLATION. NUTRIENT DEPRIVATION SUPPRESSES PROTEIN SYNTHESIS BY BLOCKING PEPTIDE ELONGATION. TRANSCRIPTIONAL UPREGULATION AND ACTIVATION OF EUKARYOTIC ELONGATION FACTOR 2 KINASE (EEF2K) BLOCKS PEPTIDE ELONGATION BY PHOSPHORYLATING EUKARYOTIC ELONGATION FACTOR 2. PREVIOUS STUDIES EXAMINING PLACENTAS FROM INTRAUTERINE GROWTH RESTRICTED (IUGR) NEWBORN INFANTS SHOW DECREASED EEF2K EXPRESSION AND ACTIVITY DESPITE CHRONIC NUTRIENT DEPRIVATION. HOWEVER, THE EFFECT OF IUGR ON HEPATIC EEF2K EXPRESSION IN THE FETUS IS UNKNOWN. WE, THEREFORE, EXAMINED THE TRANSCRIPTIONAL REGULATION OF HEPATIC EEF2K GENE EXPRESSION IN A SPRAGUE-DAWLEY RAT MODEL OF IUGR. WE FOUND DECREASED HEPATIC EEF2K MRNA AND PROTEIN LEVELS IN IUGR OFFSPRING AT BIRTH COMPARED WITH CONTROL, CONSISTENT WITH PREVIOUS PLACENTAL OBSERVATIONS. FURTHERMORE, THE CPG ISLAND WITHIN THE EEF2K PROMOTER DEMONSTRATED INCREASED METHYLATION AT A CRITICAL USF 1/2 TRANSCRIPTION FACTOR BINDING SITE. IN VITRO METHYLATION OF THIS BINDING SITE CAUSED NEAR COMPLETE LOSS OF EEF2K PROMOTER ACTIVITY, DESIGNATING THIS PROMOTER AS METHYLATION SENSITIVE. THE EEF2K PROMOTOR IN IUGR OFFSPRING ALSO LOST THE PROTECTIVE HISTONE COVALENT MODIFICATIONS ASSOCIATED WITH UNMETHYLATED CGIS. IN ADDITION, THE +1 NUCLEOSOME WAS DISPLACED 3' AND RNA POLYMERASE LOADING WAS REDUCED AT THE IUGR EEF2K PROMOTER. OUR FINDINGS PROVIDE EVIDENCE TO EXPLAIN WHY IUGR-INDUCED CHRONIC NUTRIENT DEPRIVATION DOES NOT RESULT IN THE UPREGULATION OF EEF2K GENE TRANSCRIPTION. 2016 16 2246 25 EPIGENETIC MODULATION OF INFLAMMATION AND SYNAPTIC PLASTICITY PROMOTES RESILIENCE AGAINST STRESS IN MICE. MAJOR DEPRESSIVE DISORDER IS ASSOCIATED WITH ABNORMALITIES IN THE BRAIN AND THE IMMUNE SYSTEM. CHRONIC STRESS IN ANIMALS SHOWED THAT EPIGENETIC AND INFLAMMATORY MECHANISMS PLAY IMPORTANT ROLES IN MEDIATING RESILIENCE AND SUSCEPTIBILITY TO DEPRESSION. HERE, THROUGH A HIGH-THROUGHPUT SCREENING, WE IDENTIFY TWO PHYTOCHEMICALS, DIHYDROCAFFEIC ACID (DHCA) AND MALVIDIN-3'-O-GLUCOSIDE (MAL-GLUC) THAT ARE EFFECTIVE IN PROMOTING RESILIENCE AGAINST STRESS BY MODULATING BRAIN SYNAPTIC PLASTICITY AND PERIPHERAL INFLAMMATION. DHCA/MAL-GLUC ALSO SIGNIFICANTLY REDUCES DEPRESSION-LIKE PHENOTYPES IN A MOUSE MODEL OF INCREASED SYSTEMIC INFLAMMATION INDUCED BY TRANSPLANTATION OF HEMATOPOIETIC PROGENITOR CELLS FROM STRESS-SUSCEPTIBLE MICE. DHCA REDUCES PRO-INFLAMMATORY INTERLEUKIN 6 (IL-6) GENERATIONS BY INHIBITING DNA METHYLATION AT THE CPG-RICH IL-6 SEQUENCES INTRONS 1 AND 3, WHILE MAL-GLUC MODULATES SYNAPTIC PLASTICITY BY INCREASING HISTONE ACETYLATION OF THE REGULATORY SEQUENCES OF THE RAC1 GENE. PERIPHERAL INFLAMMATION AND SYNAPTIC MALADAPTATION ARE IN LINE WITH NEWLY HYPOTHESIZED CLINICAL INTERVENTION TARGETS FOR DEPRESSION THAT ARE NOT ADDRESSED BY CURRENTLY AVAILABLE ANTIDEPRESSANTS. 2018 17 918 29 CHRONIC HYPERGRAVITY INDUCES A MODIFICATION OF HISTONE H3 LYSINE 27 TRIMETHYLATION AT TCRBETA LOCUS IN MURINE THYMOCYTES. GRAVITY CHANGES ARE MAJOR STRESSORS ENCOUNTERED DURING SPACEFLIGHT THAT AFFECT THE IMMUNE SYSTEM. WE PREVIOUSLY EVIDENCED THAT HYPERGRAVITY EXPOSURE DURING GESTATION AFFECTS THE TCRBETA REPERTOIRE OF NEWBORN PUPS. TO IDENTIFY THE MECHANISMS UNDERLYING THIS OBSERVATION, WE STUDIED POST-TRANSLATIONAL HISTONE MODIFICATIONS. WE FIRST SHOWED THAT AMONG THE FOUR STUDIED POST-TRANSLATIONAL HISTONE H3 MODIFICATIONS, ONLY LYSINE 27 TRIMETHYLATION (H3K27ME3) IS DOWNREGULATED IN THE THYMUS OF MICE EXPOSED TO 2X G FOR 21 DAYS. WE THEN ASKED WHETHER THE TCRBETA LOCUS CHROMATIN STRUCTURE IS ALTERED BY HYPERGRAVITY EXPOSURE. CHIP STUDIES PERFORMED ON FOUR VBETA SEGMENTS OF THE MURINE DOUBLE-NEGATIVE SCIET27 THYMIC CELL LINE, WHICH CORRESPONDS TO THE LAST MATURATION STAGE BEFORE V(D)J RECOMBINATION, REVEALED INCREASES IN H3K27ME3 AFTER 2X G EXPOSURE. FINALLY, WE EVALUATED THE IMPLICATION FOR THE EZH2 METHYLTRANSFERASE IN THE REGULATION OF THE H3K27ME3 LEVEL AT THESE VBETA SEGMENTS BY TREATING SCIET27 CELLS WITH THE GSK126-SPECIFIC INHIBITOR. THESE EXPERIMENTS SHOWED THAT THE DOWNREGULATION OF H3K27ME3 CONTRIBUTES TO THE REGULATION OF THE VBETA GERMLINE TRANSCRIPT EXPRESSION THAT PRECEDES V(D)J RECOMBINATION. THESE DATA SHOW THAT MODIFICATIONS OF H3K27ME3 AT THE TCRBETA LOCUS LIKELY CONTRIBUTE TO AN EXPLANATION OF WHY THE TCR REPERTOIRE IS AFFECTED BY GRAVITY CHANGES AND IMPLY, FOR THE FIRST TIME, EZH2 IN THE REGULATION OF THE TCRBETA LOCUS CHROMATIN STRUCTURE. 2022 18 6132 29 THE EPIGENETIC REGULATORS BMI1 AND RING1B ARE DIFFERENTIALLY REGULATED IN PANCREATITIS AND PANCREATIC DUCTAL ADENOCARCINOMA. CHRONIC PANCREATITIS AND PANCREATIC DUCTAL ADENOCARCINOMA (PDAC) ARE ASSOCIATED WITH MAJOR CHANGES IN CELL DIFFERENTIATION. THESE CHANGES MAY BE AT THE BASIS OF THE INCREASED RISK FOR PDAC AMONG PATIENTS WITH CHRONIC PANCREATITIS. POLYCOMB PROTEINS ARE EPIGENETIC SILENCERS EXPRESSED IN ADULT STEM CELLS; UP-REGULATION OF POLYCOMB PROTEINS HAS BEEN REPORTED TO OCCUR IN A VARIETY OF SOLID TUMOURS SUCH AS COLON AND BREAST CANCER. WE HYPOTHESIZED THAT POLYCOMB MIGHT PLAY A ROLE IN PRENEOPLASTIC STATES IN THE PANCREAS AND IN TUMOUR DEVELOPMENT/PROGRESSION. TO TEST THESE IDEAS, WE DETERMINED THE EXPRESSION OF PRC1 COMPLEX PROTEINS (BMI1 AND RING1B) DURING PANCREATIC DEVELOPMENT AND IN PANCREATIC TISSUE FROM MOUSE MODELS OF DISEASE: ACUTE AND CHRONIC PANCREATIC INJURY, DUCT LIGATION, AND IN K-RAS(G12V) CONDITIONAL KNOCK-IN AND CAERULEIN-TREATED K-RAS(G12V) MICE. THE STUDY WAS EXTENDED TO HUMAN PANCREATIC TISSUE SAMPLES. TO OBTAIN MECHANISTIC INSIGHTS, BMI1 EXPRESSION IN CELLS UNDERGOING IN VITRO EXOCRINE CELL METAPLASIA AND THE EFFECTS OF BMI1 DEPLETION IN AN ACINAR CANCER CELL LINE WERE STUDIED. WE FOUND THAT BMI1 AND RING1B ARE EXPRESSED IN PANCREATIC EXOCRINE PRECURSOR CELLS DURING EARLY DEVELOPMENT AND IN DUCTAL AND ISLET CELLS-BUT NOT ACINAR CELLS-IN THE ADULT PANCREAS. BMI1 EXPRESSION WAS INDUCED IN ACINAR CELLS DURING ACUTE INJURY, IN ACINAR-DUCTAL METAPLASTIC LESIONS, AS WELL AS IN PANCREATIC INTRAEPITHELIAL NEOPLASIA (PANIN) AND PDAC. IN CONTRAST, RING1B EXPRESSION WAS ONLY SIGNIFICANTLY AND PERSISTENTLY UP-REGULATED IN HIGH-GRADE PANINS AND IN PDAC. BMI1 KNOCKDOWN IN CULTURED ACINAR TUMOUR CELLS LED TO CHANGES IN THE EXPRESSION OF VARIOUS DIGESTIVE ENZYMES. OUR RESULTS SUGGEST THAT BMI1 AND RING1B ARE MODULATED IN PANCREATIC DISEASES AND COULD CONTRIBUTE DIFFERENTLY TO TUMOUR DEVELOPMENT. 2009 19 5713 33 SIRT2 INHIBITION REVERSES ANHEDONIA IN THE VGLUT1+/- DEPRESSION MODEL. SOME HISTONE DEACETYLASE (HDACS) ENZYMES HAVE BEEN PROPOSED AS EPIGENETIC TARGETS INVOLVED IN THE PATHOPHYSIOLOGY OF DEPRESSION AND ANTIDEPRESSANT-LIKE ACTION. AMONG THEM, WE HAVE RECENTLY IDENTIFIED SIRT2, A CLASS III NAD(+)-DEPENDENT HDAC, AS BEING OPPOSITELY REGULATED BY STRESS AND ANTIDEPRESSANTS. MOREOVER, SIRT2 INHIBITION HAS SHOWN ANTIANHEDONIC-LIKE ACTION IN THE CHRONIC MILD STRESS MODEL OF DEPRESSION. HERE WE HAVE EXTENDED THE STUDY USING AN ALTERNATIVE MODEL OF DEPRESSION BASED IN A GENETIC MANIPULATION OF GLUTAMATE FUNCTION. SPECIFICALLY, MICE HETEROZYGOUS FOR THE VESICULAR GLUTAMATE TRANSPORTER 1 (VGLUT1+/-) WERE USED. FIRSTLY, MRNA EXPRESSION OF THE DIFFERENT MEMBERS OF THE HDAC SUPERFAMILY IN THE PREFRONTAL CORTEX (PFC) OF VGLUT1+/- MICE AND WT LITTERMATES WERE STUDIED BY RT-PCR. SECONDLY, THE EFFECT OF REPEATED TREATMENT WITH THE SELECTIVE SIRT2 INHIBITOR 33I AND THE ANTIDEPRESSANT IMIPRAMINE ON ANHEDONIC BEHAVIOUR OF VGLUT1+/- MICE WAS STUDIED BY WEEKLY MONITORING OF SUCROSE INTAKE. FURTHER, THE INTERACTION OF 33I TOWARDS SPECIFIC MONOAMINERGIC TARGETS SUCH AS SEROTONIN OR NORADRENALINE TRANSPORTERS AS WELL AS THE MONOAMINOOXIDASE ENZYME WAS STUDIED. THE MRNA OCCURANCE OF THE DIFFERENT MEMBERS OF HDAC SUPERFAMILY WAS NOT ALTERED IN THE PFC OF VGLUT1+/- MICE. WHILE REPEATED IMIPRAMINE SHOWED AN ANTI-ANHEDONIC ACTION IN BOTH VGLUT1+/- AND WT, THE SELECTIVE SIRT2 INHIBITOR 33I FULLY REVERSED ANHEDONIA OF VGLUT1+/-. FURTHER, 33I SHOWED NO INTERACTION WITH THE ABOVE MENTIONED MONOAMINERGIC MOLECULAR TARGETS. THESE RESULTS CONFIRM THAT SIRT2 INHIBITION IS ABLE TO REVERSE ANHEDONIA IN DIFFERENT ANIMAL MODELS AND HIGHLIGHT THE NEED TO FURTHER INVESTIGATE THE ROLE OF SIRT2 INHIBITORS AS NEW ANTIDEPRESSANT AGENTS. 2017 20 1191 33 CORRELATION BETWEEN THE EPIGENETIC MODIFICATION OF HISTONE H3K9 ACETYLATION OF NR2B GENE PROMOTER IN RAT HIPPOCAMPUS AND ETHANOL WITHDRAWAL SYNDROME. PATIENTS WITH ALCOHOL USE DISORDER MAY DEVELOP ACUTE ETHANOL WITHDRAWAL SYNDROME (EWS). PREVIOUS STUDIES SHOWED THAT AN EPIGENETIC MODIFICATION OF THE N-METHYL-D-ASPARTATE (NMDA) RECEPTOR, ESPECIALLY NMDA RECEPTOR 2B SUBUNIT (NR2B), WAS INVOLVED IN THE PATHOLOGICAL PROCESS OF EWS. HOWEVER, THE RELATIONSHIP BETWEEN THE EPIGENETIC REGULATION OF THE NR2B GENE IN THE RAT HIPPOCAMPUS REGION AND EWS WERE INCONSISTENT. THE PURPOSE OF THIS STUDY WAS TO EXPLORE THE ROLE OF THE HISTONE H3K9 ACETYLATION OF THE NR2B GENE IN THE RAT HIPPOCAMPUS REGION IN EWS. A RAT MODEL OF CHRONIC ETHANOL EXPOSURE WAS ESTABLISHED. EWS SCORE AND THE BEHAVIORAL CHANGES WERE RECORDED AT DIFFERENT TIME POINTS. THE NR2B EXPRESSION LEVELS AND THE HISTONE H3K9 ACETYLATION LEVEL IN THE NR2B GENE PROMOTER REGION WERE MEASURED USING QRT-PCR, WESTERN BLOT, IMMUNOFLUORESCENCE, AND CHROMATIN IMMUNOPRECIPITATION, RESPECTIVELY. FINALLY, THE RELATIONSHIP BETWEEN THE EPIGENETIC MODIFICATION OF HISTONE H3K9 ACETYLATION OF NR2B GENE PROMOTER AND EWS WERE EXAMINED. OUR ULTIMATE RESULTS SHOWED THAT THE EWS SCORE WAS INCREASED AT 2 H, PEAKED AT 6 H AFTER WITHDRAWAL OF ETHANOL, AND REDUCED TO THE LEVEL PARALLEL TO THE NORMAL CONTROL GROUP AT DAY 3 AFTER ETHANOL WITHDRAWAL. THE NR2B MRNA EXPRESSION AND PROTEIN LEVELS SHOWED SIMILAR PATTERNS. FURTHER CORRELATION ANALYSES INDICTED THAT BOTH HISTONE H3K9 ACETYLATION IN NR2B GENE PROMOTER AND THE EXPRESSION LEVELS OF NR2B WERE POSITIVELY ASSOCIATED WITH EWS. OUR RESULTS SUGGEST THAT CHRONIC ETHANOL EXPOSURE MAY RESULT IN EPIGENETIC MODIFICATION OF HISTONE H3K9 ACETYLATION IN NR2B GENE PROMOTER IN RAT HIPPOCAMPUS, AND THE EXPRESSION LEVELS OF NR2B WERE FOUND TO BE POSITIVELY CORRELATED WITH ETHANOL WITHDRAWAL SYNDROME. 2019