1  5651 117 SEX DIFFERENCES IN THE EPIGENETIC REGULATION OF CHRONIC VISCERAL PAIN FOLLOWING UNPREDICTABLE EARLY LIFE STRESS. BACKGROUND: WE PREVIOUSLY REPORTED THAT EARLY LIFE STRESS (ELS) DYSREGULATED GLUCOCORTICOID RECEPTOR (GR) AND CORTICOTROPHIN-RELEASING HORMONE (CRH) EXPRESSION IN THE CENTRAL NUCLEUS OF THE AMYGDALA (CEA). EPIGENETIC MODIFICATIONS SERVE AS MEMORIES OF ADVERSE EVENTS THAT OCCURRED DURING EARLY LIFE. THEREFORE, WE HYPOTHESIZED THAT EPIGENETIC MECHANISMS ALTER GR AND CRH EXPRESSION IN THE CEA AND UNDERLIE CHRONIC VISCERAL PAIN AFTER ELS. METHODS: NEONATAL RATS WERE EXPOSED TO UNPREDICTABLE, PREDICTABLE ELS, OR ODOR ONLY (NO STRESS CONTROL) FROM POSTNATAL DAYS 8 TO 12. IN ADULTHOOD, VISCERAL SENSITIVITY WAS ASSESSED OR THE CEA WAS ISOLATED FOR WESTERN BLOT OR CHIP-QPCR TO STUDY HISTONE MODIFICATIONS AT THE GR AND CRH PROMOTERS. FEMALE ADULT RATS UNDERWENT STEREOTAXIC IMPLANTATION OF INDWELLING CANNULAS FOR MICROINJECTIONS OF GARCINOL (HAT INHIBITOR) INTO THE CEA. AFTER 7 DAYS OF MICROINJECTIONS, VISCERAL SENSITIVITY WAS ASSESSED OR THE CEA WAS ISOLATED FOR CHIP-QPCR ASSAYS. RESULTS: UNPREDICTABLE ELS INCREASED VISCERAL SENSITIVITY IN ADULT FEMALE RATS, BUT NOT IN MALE COUNTERPARTS. ELS INCREASED HISTONE 3 LYSINE 9 (H3K9) ACETYLATION IN THE CEA AND H3K9 ACETYLATION LEVELS AT THE GR PROMOTER IN THE CEA OF ADULT FEMALE RATS. AFTER UNPREDICTABLE ELS, H3K9 ACETYLATION WAS INCREASED AND GR BINDING WAS DECREASED AT THE CRH PROMOTER. ADMINISTRATION OF GARCINOL IN THE CEA OF ADULT FEMALES, THAT UNDERWENT UNPREDICTABLE ELS, NORMALIZED H3K9 ACETYLATION AND RESTORED GR BINDING AT THE CRH PROMOTER. CONCLUSION: DYSREGULATED HISTONE ACETYLATION AND GR BINDING AT THE CRH PROMOTER IN THE CEA ARE AN IMPORTANT MECHANISM FOR "MEMORIZING" ELS EVENTS MEDIATING VISCERAL PAIN IN ADULTHOOD.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       
2  2187  78 EPIGENETIC MECHANISMS UNDERLYING STRESS-INDUCED VISCERAL PAIN: RESILIENCE VERSUS VULNERABILITY IN A TWO-HIT MODEL OF EARLY LIFE STRESS AND CHRONIC ADULT STRESS. BACKGROUND: WOMEN WITH A HISTORY OF EARLY LIFE STRESS (ELS) HAVE A HIGHER RISK OF DEVELOPING IRRITABLE BOWEL SYNDROME (IBS). IN ADDITION, CHRONIC STRESS IN ADULTHOOD CAN EXACERBATE IBS SYMPTOMS SUCH AS ABDOMINAL PAIN DUE TO VISCERAL HYPERSENSITIVITY. WE PREVIOUSLY SHOWED THAT SEX AND THE PREDICTABILITY OF ELS DETERMINE WHETHER RATS DEVELOP VISCERAL HYPERSENSITIVITY IN ADULTHOOD. IN FEMALE RATS, UNPREDICTABLE ELS CONFERS VULNERABILITY AND RESULTS IN VISCERAL HYPERSENSITIVITY, WHEREAS PREDICTABLE ELS INDUCES RESILIENCE AND DOES NOT INDUCE VISCERAL HYPERSENSITIVITY IN ADULTHOOD. HOWEVER, THIS RESILIENCE IS LOST AFTER EXPOSURE TO CHRONIC STRESS IN ADULTHOOD LEADING TO AN EXACERBATION OF VISCERAL HYPERSENSITIVITY. EVIDENCE SUGGESTS THAT CHANGES IN HISTONE ACETYLATION AT THE PROMOTER REGIONS OF GLUCOCORTICOID RECEPTOR (GR) AND CORTICOTROPHIN-RELEASING FACTOR (CRF) IN THE CENTRAL NUCLEUS OF THE AMYGDALA (CEA) UNDERLIE STRESS-INDUCED VISCERAL HYPERSENSITIVITY. HERE, WE AIMED TO INVESTIGATE THE ROLE OF HISTONE ACETYLATION IN THE CEA ON VISCERAL HYPERSENSITIVITY IN A TWO-HIT MODEL OF ELS FOLLOWED BY CHRONIC STRESS IN ADULTHOOD. METHODS: MALE AND FEMALE NEONATAL RATS WERE EXPOSED TO UNPREDICTABLE, PREDICTABLE ELS, OR ODOR ONLY (NO STRESS CONTROL) FROM POSTNATAL DAYS 8 TO 12. IN ADULTHOOD, RATS UNDERWENT STEREOTAXIC IMPLANTATION OF INDWELLING CANNULAS. RATS WERE EXPOSED TO CHRONIC WATER AVOIDANCE STRESS (WAS, 1 H/DAY FOR 7 DAYS) OR SHAM STRESS AND RECEIVED INFUSIONS OF VEHICLE, THE HISTONE DEACETYLASE INHIBITOR TRICHOSTATIN A (TSA) OR THE HISTONE ACETYLTRANSFERASE INHIBITOR GARCINOL (GAR) AFTER EACH WAS SESSION. 24 H AFTER THE FINAL INFUSION, VISCERAL SENSITIVITY WAS ASSESSED AND THE CEA WAS REMOVED FOR MOLECULAR EXPERIMENTS. RESULTS: IN THE TWO-HIT MODEL (ELS + WAS), FEMALE RATS PREVIOUSLY EXPOSED TO PREDICTABLE ELS, SHOWED A SIGNIFICANT REDUCTION IN HISTONE 3 LYSINE 9 (H3K9) ACETYLATION AT THE GR PROMOTER AND A SIGNIFICANT INCREASE IN H3K9 ACETYLATION AT THE CRF PROMOTER. THESE EPIGENETIC CHANGES WERE ASSOCIATED WITH CHANGES IN GR AND CRF MRNA EXPRESSION IN THE CEA AND AN EXACERBATION OF STRESS-INDUCED VISCERAL HYPERSENSITIVITY IN FEMALE ANIMALS. TSA INFUSIONS IN THE CEA ATTENUATED THE EXACERBATED STRESS-INDUCED VISCERAL HYPERSENSITIVITY, WHEREAS GAR INFUSIONS ONLY PARTIALLY AMELIORATED ELS+WAS INDUCED VISCERAL HYPERSENSITIVITY. CONCLUSION: THE TWO-HIT MODEL OF ELS FOLLOWED BY WAS IN ADULTHOOD REVEALED THAT EPIGENETIC DYSREGULATION OCCURS AFTER EXPOSURE TO STRESS IN TWO IMPORTANT PERIODS OF LIFE AND CONTRIBUTES TO THE DEVELOPMENT OF VISCERAL HYPERSENSITIVITY. THESE ABERRANT UNDERLYING EPIGENETIC CHANGES MAY EXPLAIN THE EXACERBATION OF STRESS-INDUCED ABDOMINAL PAIN IN IBS PATIENTS.	2023	
                                                                                                                                                                                                                  
3  3600  53 IMPORTANCE OF EPIGENETIC MECHANISMS IN VISCERAL PAIN INDUCED BY CHRONIC WATER AVOIDANCE STRESS. EPIGENETIC MOLECULAR MECHANISMS, WHICH INCLUDE DNA METHYLATION AND HISTONE DEACETYLATION, ARE IMPLICATED IN THE DYSREGULATION OF THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS. PREVIOUSLY, WE DEMONSTRATED THAT REPEATED WATER AVOIDANCE STRESS (WAS), A VALIDATED MODEL OF CHRONIC PSYCHOLOGICAL STRESS, INDUCES HEIGHTENED VISCERAL PAIN BEHAVIORS IN RODENTS THAT RESEMBLE IRRITABLE BOWEL SYNDROME (IBS) SEQUELAE. HOWEVER, THE INVOLVEMENT OF EPIGENETIC MOLECULAR MECHANISMS IN THE PATHOPHYSIOLOGY OF STRESS-INDUCED VISCERAL PAIN HAS NOT BEEN EXPLORED. OUR HYPOTHESIS IS THAT EPIGENETIC MECHANISMS WITHIN THE CENTRAL NERVOUS SYSTEM (CNS) ARE IMPORTANT TO CHRONIC STRESS-INDUCED VISCERAL HYPERSENSITIVITY. ADULT MALE F-344 RATS WITH INTRACEREBROVENTRICULAR (I.C.V.) CANNULAE WERE EXPOSED TO 7 DAYS OF REPEATED WAS. CONTROLS RECEIVED A SHAM STRESS. FOLLOWING THE DAILY 1H STRESSOR, TRICHOSTATIN A (TSA; 100 NG/ML), A POTENT HISTONE DEACETYLASE INHIBITOR, OR VEHICLE (VEH; 0.1% DMSO/SALINE,) AS CONTROL WAS ADMINISTERED VIA THE I.C.V. CANNULA. VISCERAL SENSITIVITY WAS ASSESSED 24H AFTER THE FINAL WAS AND QUANTIFIED THE VISCEROMOTOR RESPONSE (VMR) BY RECORDING THE NUMBER OF ABDOMINAL CONTRACTIONS IN RESPONSE TO GRADED PRESSURES (20-60 MMHG) OF COLORECTAL DISTENSIONS (CRD). FROM A SEPARATE GROUP OF RATS THAT WERE EXPOSED TO REPEATED WAS OR SHAM STRESS, THE AMYGDALA WAS ISOLATED TO ASSESS THE METHYLATION STATUS OF GLUCOCORTICOID RECEPTOR (GR) AND CORTICOTROPIN RELEASING-FACTOR (CRF) GENES VIA BISULFITE SEQUENCING AND VERIFIED BY PYROSEQUENCING. GR AND CRF GENE EXPRESSION WAS QUANTIFIED VIA QRT-PCR. STRESSED RATS EXHIBITED VISCERAL HYPERSENSITIVITY THAT WAS SIGNIFICANTLY ATTENUATED BY TSA. COMPARED TO SHAM CONTROLS, METHYLATION OF THE GR GENE WAS INCREASED FOLLOWING WAS WHILE EXPRESSION OF THE GR GENE WAS DECREASED. METHYLATION OF THE CRF PROMOTER WAS DECREASED WITH WAS WITH A CONCOMITANT INCREASE IN CRF EXPRESSION. THIS STUDY DEMONSTRATES THE INVOLVEMENT OF CENTRAL EPIGENETIC MECHANISMS IN REGULATING STRESS-INDUCED VISCERAL HYPERSENSITIVITY AND PROVIDES A FOUNDATION FOR EXPLORING THE EPIGENETIC MECHANISMS THAT MAY CONTRIBUTE TO IBS-LIKE SYMPTOMATOLOGY.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
4  1163  56 CONTRIBUTION OF AMYGDALA HISTONE ACETYLATION IN EARLY LIFE STRESS-INDUCED VISCERAL HYPERSENSITIVITY AND EMOTIONAL COMORBIDITY. PATIENTS WITH IRRITABLE BOWEL SYNDROME (IBS) EXPERIENCE NOT ONLY ENHANCED VISCERAL PAIN BUT ALSO EMOTIONAL COMORBIDITIES, SUCH AS ANXIETY AND DEPRESSION. EARLY LIFE STRESS (ELS) IS A HIGH-RISK FOR THE DEVELOPMENT OF IBS. LITERATURES HAVE REPORTED AN IMPORTANT EPIGENETIC MODULATION IN SUSTAINING EXTRINSIC PHENOTYPES. THE AMYGDALA IS CLOSELY RELATED TO THE REGULATION OF VISCERAL FUNCTIONS AND EMOTIONAL EXPERIENCES. IN THIS STUDY, WE HYPOTHESIZED THAT ELS-INDUCED REPROGRAMMING INAPPROPRIATE ADAPTATION OF HISTONE ACETYLATION MODIFICATION IN THE AMYGDALA MAY RESULT IN VISCERAL HYPERSENSITIVITY AND ANXIETY-LIKE BEHAVIORS IN ELS RATS. TO TEST THIS HYPOTHESIS, THE MODEL OF ELS RATS WAS ESTABLISHED BY NEONATAL COLORECTAL DILATATION (CRD). VISCERAL HYPERSENSITIVITY WAS ASSESSED BASED ON THE ELECTROMYOGRAPHY RESPONSE OF THE ABDOMINAL EXTERNAL OBLIQUE MUSCLE TO CRD. EMOTIONAL COMORBIDITIES WERE EXAMINED USING THE ELEVATED PLUS MAZE TEST, OPEN FIELD TEST, AND SUCROSE PREFERENCE TEST. TRICHOSTATIN A (TSA) AND C646 WERE MICROINJECTED INTO THE CENTRAL AMYGDALA (CEA) INDIVIDUALLY TO INVESTIGATE THE EFFECTS OF DIFFERENT LEVELS OF HISTONE ACETYLATION MODIFICATION ON VISCERAL HYPERSENSITIVITY AND EMOTION. WE FOUND NEONATAL CRD RESULTED IN VISCERAL HYPERSENSITIVITY AND ANXIETY-LIKE BEHAVIORS AFTER ADULTHOOD. INHIBITING HISTONE DEACETYLASES (HDACS) IN THE CEA BY TSA ENHANCED VISCERAL SENSITIVITY BUT DID NOT AFFECT ANXIETY-LIKE BEHAVIORS, WHEREAS INHIBITING HAT BY C646 ATTENUATED VISCERAL HYPERSENSITIVITY IN ELS RATS. INTERESTINGLY, CEA TREATMENT WITH TSA INDUCED VISCERAL SENSITIVITY AND ANXIETY-LIKE BEHAVIORS IN THE CONTROL RATS. WESTERN BLOT SHOWED THAT THE EXPRESSIONS OF ACETYLATED 9 RESIDUE OF HISTONE 3 (H3K9) AND PROTEIN KINASE C ZETA TYPE (PKMZETA) WERE HIGHER IN THE ELS RATS COMPARED TO THOSE OF THE CONTROLS. THE ADMINISTRATION OF THE PKMZETA INHIBITOR ZIP INTO THE CEA ATTENUATED VISCERAL HYPERSENSITIVITY OF ELS RATS. FURTHERMORE, THE EXPRESSION OF AMYGDALA PKMZETA WAS ENHANCED BY TSA TREATMENT IN CONTROL RATS. FINALLY, WESTERN BLOT AND IMMUNOFLUORESCENCE RESULTS INDICATED THE DECREASE OF HDAC1 AND HDAC2 EXPRESSIONS, BUT NOT HDAC3 EXPRESSION, CONTRIBUTED TO THE ENHANCEMENT OF HISTONE ACETYLATION IN ELS RATS. OUR RESULTS SUPPORT OUR HYPOTHESIS THAT AMYGDALA-ENHANCED HISTONE ACETYLATION INDUCED BY STRESS IN EARLY LIFE RESULTS IN VISCERAL HYPERSENSITIVITY AND ANXIETY-LIKE BEHAVIORS IN ELS RATS, AND REVERSING THE ABNORMAL EPIGENETIC MECHANISMS MAY BE CRUCIAL TO RELIEVE CHRONIC SYMPTOMS IN ELS RATS.	2022	
                                                                                                                                                                                                                                                                                                                                                                                                                                                        
5  5834  40 STRESS-INDUCED VISCERAL PAIN IN FEMALE RATS IS ASSOCIATED WITH EPIGENETIC REMODELING IN THE CENTRAL NUCLEUS OF THE AMYGDALA. STRESS AND ANXIETY CONTRIBUTE TO THE PATHOPHYSIOLOGY OF IRRITABLE BOWEL SYNDROME (IBS), A FEMALE-PREDOMINANT DISORDER OF THE GUT-BRAIN AXIS, CHARACTERIZED BY ABDOMINAL PAIN DUE TO HEIGHTENED VISCERAL SENSITIVITY. IN THE CURRENT STUDY, WE AIMED TO EVALUATE IN FEMALE RATS WHETHER EPIGENETIC REMODELING IN THE LIMBIC BRAIN, SPECIFICALLY IN THE CENTRAL NUCLEUS OF THE AMYGDALA (CEA), IS A CONTRIBUTING FACTOR IN STRESS-INDUCED VISCERAL HYPERSENSITIVITY. OUR RESULTS SHOWED THAT 1 H EXPOSURE TO WATER AVOIDANCE STRESS (WAS) FOR 7 CONSECUTIVE DAYS DECREASED HISTONE ACETYLATION AT THE GR PROMOTER AND INCREASED HISTONE ACETYLATION AT THE CRH PROMOTER IN THE CEA. CHANGES IN HISTONE ACETYLATION WERE MEDIATED BY THE HISTONE DEACETYLASE (HDAC) SIRT-6 AND THE HISTONE ACETYLTRANSFERASE CBP, RESPECTIVELY. ADMINISTRATION OF THE HDAC INHIBITOR TRICHOSTATIN A (TSA) INTO THE CEA PREVENTED STRESS-INDUCED VISCERAL HYPERSENSITIVITY THROUGH BLOCKADE OF SIRT-6 MEDIATED HISTONE ACETYLATION AT THE GR PROMOTER. IN ADDITION, HDAC INHIBITION WITHIN THE CEA PREVENTED STRESS-INDUCED HISTONE ACETYLATION OF THE CRH PROMOTER. OUR RESULTS SUGGEST THAT, IN FEMALES, EPIGENETIC MODIFICATIONS IN THE LIMBIC BRAIN REGULATING GR AND CRH EXPRESSION CONTRIBUTE TO STRESS-INDUCED VISCERAL HYPERSENSITIVITY AND OFFER A POTENTIAL EXPLANATION OF HOW STRESS CAN TRIGGER SYMPTOMS IN IBS PATIENTS.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
6  1920  48 ENVIRONMENTAL ENRICHMENT PREVENTS STRESS-INDUCED EPIGENETIC CHANGES IN THE EXPRESSION OF GLUCOCORTICOID RECEPTOR AND CORTICOTROPHIN RELEASING HORMONE IN THE CENTRAL NUCLEUS OF THE AMYGDALA TO INHIBIT VISCERAL HYPERSENSITIVITY. INTRODUCTION: STRESS IS A KNOWN TRIGGER FOR THE SYMPTOMS OF IRRITABLE BOWEL SYNDROME (IBS), A GASTROINTESTINAL (GI) DISORDER THAT PRESENTS WITH ABNORMAL BOWEL HABITS AND ABDOMINAL PAIN DUE TO VISCERAL HYPERSENSITIVITY. WHILE BEHAVIORAL THERAPIES HAVE BEEN USED TO ATTENUATE IBS SYMPTOMS, THE UNDERLYING MECHANISMS BY WHICH THESE THERAPIES INTERACT WITH STRESS-INDUCED PATHOLOGY REMAINS TO BE DELINEATED. HERE WE USE A RAT MODEL TO TEST THE HYPOTHESIS THAT EXPOSURE TO ENVIRONMENTAL ENRICHMENT (EE) INHIBITS STRESS-INDUCED CHANGES WITHIN THE BRAIN-GUT AXIS TO PREVENT VISCERAL AND SOMATIC HYPERSENSITIVITY AND COLONIC HYPERPERMEABILITY. METHODS: FEMALE RATS (N = 8/GROUP) WERE HOUSED IN EE ONE WEEK BEFORE AND ONE WEEK DURING EXPOSURE TO WATER AVOIDANCE STRESS (WAS) WHILE CONTROLS WERE HOUSED IN STANDARD CAGES (SH). ONE DAY AFTER THE FINAL WAS EXPOSURE, COLONIC AND SOMATIC SENSITIVITY WERE ASSESSED BY THE VISCEROMOTOR RESPONSE (VMR) TO COLORECTAL DISTENSION (CRD) AND WITHDRAWAL THRESHOLD ELICITED BY AN ELECTRONIC VON FREY ON THE HIND PAW OF THE RATS RESPECTIVELY. ALL RATS WERE RETURNED TO SH FOR 3 WEEKS BEFORE COLONIC AND SOMATIC SENSITIVITY WERE REASSESSED ON DAY 28. THE RATS WERE THEN IMMEDIATELY EUTHANIZED AND THE SPINAL CORD WAS COLLECTED TO ASSESS CHANGES IN NEURONAL ACTIVATION (ASSESSED VIA ERK PHOSPHORYLATION) IN RESPONSE TO NOXIOUS CRD. A SEPARATE COHORT OF ANIMALS (N = 8/GROUP) THAT DID NOT UNDERGO BEHAVIORAL ASSESSMENTS WAS EUTHANIZED THE DAY AFTER THE FINAL WAS EXPOSURE AND THE CENTRAL NUCLEUS OF THE AMYGDALA (CEA) WAS COLLECTED TO INVESTIGATE WAS AND EE INDUCED EPIGENETIC CHANGES AT THE GLUCOCORTICOID RECEPTOR (GR) AND CORTICOTROPHIN RELEASING HORMONE (CRH) PROMOTER. THE COLON FROM THESE RATS WAS ALSO COLLECTED TO ASSESS COLONIC PERMEABILITY VIA CHANGES IN TRANSEPITHELIAL ELECTRICAL RESISTANCE (TEER) IN VITRO. RESULTS: EXPOSURE TO STRESS PERSISTENTLY INCREASED VMR TO CRD (P < 0.01) AND DECREASED THE HIND PAW WITHDRAWAL THRESHOLD (P < 0.001) IN FEMALE RATS. WAS ALSO DECREASED TEER IN THE COLON TISSUE OF FEMALE RATS (P = 0.05). IN THE CEA, WAS INDUCED A DECREASE IN HISTONE ACETYLATION AT THE GR PROMOTER BUT INCREASED HISTONE ACETYLATION AT THE CRH PROMOTER AND REDUCED GR-CRH INTERACTIONS IN THE CEA. ANALYSIS OF THE SPINAL CORD SHOWED THAT WAS INCREASED CRD-EVOKED ERK PHOSPHORYLATION IN THE DORSAL HORN. EXPOSURE TO EE PREVENTED WAS-INDUCED CHANGES IN THE CEA, DORSAL HORN AND COLON RESPECTIVELY TO PREVENT VISCERAL AND SOMATIC HYPERSENSITIVITY. CONCLUSION: OUR DATA REVEALS THAT BEHAVIORAL THERAPIES CAN PRODUCE LONG LASTING MOLECULAR AND EPIGENETIC CHANGES THAT CAN PREVENT STRESS-INDUCED PATHOLOGIES EVEN AFTER COMPLETION OF THE THERAPY. THESE RESULTS HIGHLIGHT THE POTENTIAL MECHANISMS BY WHICH BEHAVIORAL THERAPIES MAY AMELIORATE VISCERAL PAIN ASSOCIATED STRESS-RELATED PATHOLOGIES SUCH AS THE IRRITABLE BOWEL SYNDROME.	2021	

7  1740  32 EARLY ENRICHED ENVIRONMENT PREVENTS EPIGENETIC P11 GENE CHANGES INDUCED BY ADULTHOOD STRESS IN MICE. POSITIVE EXPERIENCES IN EARLY LIFE MAY IMPROVE THE CAPACITY TO COPE WITH ADULTHOOD STRESS THROUGH EPIGENETIC MODIFICATION. WE INVESTIGATED WHETHER AN ENRICHED ENVIRONMENT (EE) IN THE POSTNATAL PERIOD AFFECTED EPIGENETIC CHANGES IN THE P11 GENE INDUCED BY CHRONIC UNPREDICTABLE STRESS (CUS) IN ADULT C57BL/6J MICE. EE WAS INTRODUCED FOR 5 WEEKS DURING POSTNATAL DAYS 21-55. AFTER EE, THE MICE WERE SUBJECTED TO CUS FOR 4 WEEKS. EE PREVENTED DEPRESSION-LIKE BEHAVIOR INDUCED BY ADULT CUS. EE PREVENTED A DECREASE IN P11 MRNA AND HISTONE H3 ACETYLATION INDUCED BY CUS, WITH CHANGES IN THE EXPRESSION OF HISTONE DEACETYLASE 5. MOREOVER, EE PREVENTED CHANGES IN TRIMETHYLATION OF HISTONE H3 LYSINE 4 (H3K4) AND H3K27 INDUCED BY CUS. FURTHERMORE, EE HAD POSITIVE EFFECTS ON BEHAVIOR AND EPIGENETIC ALTERATIONS IN ADULT MICE WITHOUT CUS. THESE RESULTS SUGGEST THAT ONE OF THE UNDERLYING MECHANISMS OF EARLY-LIFE EE MAY INVOLVE EPIGENETIC MODIFICATION OF THE HIPPOCAMPAL P11 GENE PROMOTER.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
8  4213  38 METHIONINE MEDIATES RESILIENCE TO CHRONIC SOCIAL DEFEAT STRESS BY EPIGENETIC REGULATION OF NMDA RECEPTOR SUBUNIT EXPRESSION. RATIONALE: PREVIOUS STUDIES SUGGESTED THAT METHIONINE (MET) LEVELS ARE DECREASED IN DEPRESSED PATIENTS. HOWEVER, WHETHER THE DECREASE IN THIS AMINO ACID IS IMPORTANT FOR PHENOTYPIC BEHAVIORS ASSOCIATED WITH DEPRESSION HAS NOT BEEN DECIPHERED. OBJECTIVE: THE RESPONSE OF INDIVIDUALS TO CHRONIC STRESS IS VARIABLE, WITH SOME INDIVIDUALS DEVELOPING DEPRESSION AND OTHERS BECOMING RESILIENT TO STRESS. IN THIS STUDY, OUR OBJECTIVE WAS TO EXAMINE THE EFFECT OF MET ON SUSCEPTIBILITY TO STRESS. METHODS: MALE C57BL/6J MICE WERE SUBJECTED TO DAILY DEFEAT SESSIONS BY A CD1 AGGRESSOR, FOR 10 DAYS. ON DAY 11, THE BEHAVIOR OF MICE WAS ASSESSED USING SOCIAL INTERACTION AND OPEN-FIELD TESTS. MICE RECEIVED MET 4 H BEFORE EACH DEFEAT SESSION. EPIGENETIC TARGETS WERE ASSESSED EITHER THROUGH REAL-RIME RTPCR OR THROUGH WESTERN BLOTS. RESULTS: MET DID NOT MODULATE ANXIETY-LIKE BEHAVIORS, BUT RATHER PROMOTED RESILIENCE TO CHRONIC STRESS, RESCUED SOCIAL AVOIDANCE BEHAVIORS AND REVERSED THE INCREASE IN THE CORTICAL EXPRESSION LEVELS OF N-METHYL-D-ASPARTATE RECEPTOR (NMDAR) SUBUNITS. ACTIVATING NMDAR ACTIVITY ABOLISHED THE ABILITY OF MET TO PROMOTE RESILIENCE TO STRESS AND TO RESCUE SOCIAL AVOIDANCE BEHAVIOR, WHEREAS INHIBITING NMDAR DID NOT SHOW ANY SYNERGISTIC OR ADDITIVE PROTECTIVE EFFECTS. INDEED, MET INCREASED THE CORTICAL LEVELS OF THE HISTONE METHYLTRANSFERASE SETDB1, AND IN TURN, THE LEVELS OF THE REPRESSIVE HISTONE H3 LYSINE (K9) TRIMETHYLATION (ME3). CONCLUSIONS: OUR DATA INDICATE THAT MET RESCUES SUSCEPTIBILITY TO STRESS BY INACTIVATING CORTICAL NMDAR ACTIVITY THROUGH AN EPIGENETIC MECHANISM INVOLVING HISTONE METHYLATION.	2020	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
9  5752  40 SOCIAL ISOLATION AND SOCIAL SUPPORT AT ADULTHOOD AFFECT EPIGENETIC MECHANISMS, BRAIN-DERIVED NEUROTROPHIC FACTOR LEVELS AND BEHAVIOR OF CHRONICALLY STRESSED RATS. EPIGENETIC MODULATION OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) PROVIDES ONE POSSIBLE EXPLANATION FOR THE DYSFUNCTIONS INDUCED BY STRESS, SUCH AS PSYCHIATRIC DISORDERS AND COGNITIVE DECLINE. INTERESTINGLY, SOCIAL SUPPORT CAN BE PROTECTIVE AGAINST SOME OF THESE EFFECTS, BUT THE MECHANISMS OF SOCIAL BUFFERING ARE POORLY UNDERSTOOD. CONVERSELY, EARLY ISOLATION EXACERBATES THE RESPONSES TO STRESSORS, ALTHOUGH ITS EFFECTS IN ADULTHOOD REMAIN UNCLEAR. THIS STUDY INVESTIGATED THE EFFECTS OF SOCIAL ISOLATION AND SOCIAL BUFFERING ON HIPPOCAMPAL EPIGENETIC MECHANISMS, BDNF LEVELS AND BEHAVIORAL RESPONSES OF CHRONICALLY STRESSED YOUNG ADULT RATS. MALE WISTAR RATS (3 MONTHS) WERE ASSIGNED TO ACCOMPANIED (PAIRED) OR ISOLATED HOUSING. AFTER ONE-MONTH HALF OF EACH GROUP WAS SUBMITTED TO A CHRONIC UNPREDICTABLE STRESS (CUS) PROTOCOL FOR 18 DAYS. AMONG ACCOMPANIED ANIMALS, ONLY ONE WAS EXPOSED TO STRESS. BEHAVIORAL ANALYSIS ENCOMPASSED THE OPEN FIELD, PLUS MAZE AND INHIBITORY AVOIDANCE TASKS. HIPPOCAMPAL H3K9 AND H4K12 ACETYLATION, HDAC5 EXPRESSION AND BDNF LEVELS WERE EVALUATED. ISOLATED HOUSING INCREASED HDAC5 EXPRESSION, DECREASED H3K9 AND H4K12 ACETYLATION, REDUCED BDNF LEVELS, AND IMPAIRED LONG-TERM MEMORY. STRESS AFFECTED WEIGHT GAIN, INDUCED ANXIETY-LIKE BEHAVIOR AND DECREASED ACK9H3 LEVELS. INTERACTIONS BETWEEN HOUSING CONDITIONS AND SOCIAL STRESS WERE SEEN ONLY FOR HDAC5 EXPRESSION, WHICH SHOWED A FURTHER INCREASE IN THE ISOLATED + CUS GROUP BUT REMAINED CONSTANT IN ACCOMPANIED ANIMALS. IN CONCLUSION, SOCIAL ISOLATION AT ADULTHOOD INDUCED EPIGENETIC ALTERATIONS AND EXACERBATED THE EFFECTS OF CHRONIC STRESS ON HDAC5. NOTWITHSTANDING, SOCIAL SUPPORT COUNTERACTED THE ADVERSE EFFECTS OF STRESS ON HDAC5 EXPRESSION.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
10  3177  36 H3K9ME2 REGULATION OF BDNF EXPRESSION IN THE HIPPOCAMPUS AND MEDIAL PREFRONTAL CORTEX IS INVOLVED IN THE DEPRESSIVE-LIKE PHENOTYPE INDUCED BY MATERNAL SEPARATION IN MALE RATS. BACKGROUND: EARLY LIFE STRESS (ELS) INDUCES A DEPRESSIVE-LIKE PHENOTYPE AND INCREASES THE RISK OF DEPRESSION. BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) HAS BEEN CONFIRMED TO BE INVOLVED IN THE PATHOPHYSIOLOGY OF DEPRESSION. HOWEVER, THE MECHANISM BY WHICH ELS ALTERS THE EPIGENETIC REGULATION OF BDNF AND CHANGES SUSCEPTIBILITY TO DEPRESSION HAS NOT BEEN FULLY CLARIFIED. METHODS: THE PRESENT STUDY USED MATERNAL SEPARATION (MS) AND CHRONIC UNPREDICTED MILD STRESS (CUMS) TO ESTABLISH AN MS ANIMAL MODEL AND A DEPRESSIVE ANIMAL MODEL. WE ASSESSED DEPRESSIVE-LIKE BEHAVIOURS, INCLUDING ANHEDONIA, LOCOMOTOR ACTIVITY, ANXIETY-LIKE BEHAVIOUR, AND SPATIAL MEMORY, USING THE SUCROSE PREFERENCE TEST, THE OPEN FIELD TEST, THE ELEVATED PLUS MAZE TEST, AND THE MORRIS WATER MAZE TEST. WE ALSO INVESTIGATED BDNF AND H3K9ME2 EXPRESSION IN THE HIPPOCAMPUS AND MEDIAL PREFRONTAL CORTEX (MPFC) BY IMMUNOHISTOCHEMISTRY, WESTERN BLOTTING, AND QPCR ANALYSIS. ADDITIONALLY, WE USED UNC0642, A SMALL MOLECULE INHIBITOR OF HISTONE METHYLTRANSFERASE (G9A), AS AN INTERVENTION. RESULTS: THE RESULTS SHOWED THAT CUMS INDUCED DEPRESSIVE-LIKE BEHAVIOURS IN RATS AND RESULTED IN INCREASED H3K9ME2 EXPRESSION AND DECREASED BDNF EXPRESSION IN THE HIPPOCAMPUS AND MPFC. MORE IMPORTANTLY, ADULT MS RATS EXPERIENCING CUMS HAD MORE SEVERE DEPRESSIVE BEHAVIOURS, HAD HIGHER EXPRESSION OF H3K9ME2 IN THE HIPPOCAMPUS AND MPFC, AND HAD LOWER EXPRESSION OF BDNF IN THE HIPPOCAMPUS AND MPFC. IN ADDITION, ADMINISTRATION OF THE G9A INHIBITOR REVERSED MOST OF THE CHANGES. CONCLUSIONS: OUR STUDY SUGGESTS THAT ELS CHANGED BDNF AND H3K9ME2 EXPRESSION IN THE RAT BRAIN, RESULTING IN A DEPRESSIVE-LIKE PHENOTYPE.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
11  2745  29 EXPRESS: HISTONE HYPERACETYLATION MODULATES SPINAL TYPE II METABOTROPIC GLUTAMATE RECEPTOR ALLEVIATING STRESS-INDUCED VISCERAL HYPERSENSITIVITY IN FEMALE RATS. STRESS IS OFTEN A TRIGGER TO EXACERBATE CHRONIC PAIN INCLUDING VISCERAL HYPERSENSITIVITY ASSOCIATED WITH IRRITABLE BOWEL SYNDROME, A FEMALE PREDOMINANT FUNCTIONAL BOWEL DISORDER. EPIGENETIC MECHANISMS THAT MEDIATE STRESS RESPONSES ARE A POTENTIAL TARGET TO INTERFERE WITH VISCERAL PAIN. THE PURPOSE OF THIS STUDY WAS TO EXAMINE THE EFFECT OF A HISTONE DEACETYLASE INHIBITOR, SUBEROYLANILIDE HYDROXAMIC ACID, ON VISCERAL HYPERSENSITIVITY INDUCED BY A SUBCHRONIC STRESSOR IN FEMALE RATS AND TO INVESTIGATE THE INVOLVEMENT OF SPINAL GLUTAMATE RECEPTORS. THREE DAILY SESSIONS OF FORCED SWIM INDUCED VISCERAL HYPERSENSITIVITY. INTRATHECAL SUBEROYLANILIDE HYDROXAMIC ACID PREVENTED OR REVERSED THE STRESS-INDUCED VISCERAL HYPERSENSITIVITY, INCREASED SPINAL HISTONE 3 ACETYLATION AND INCREASED MGLUR2 AND MGLUR3 EXPRESSION. CHROMATIN IMMUNOPRECIPITATION (CHIP) ANALYSIS REVEALED ENRICHMENT OF H3K9AC AND H3K18AC AT SEVERAL PROMOTER GRM2 AND GRM3 REGIONS. THE MGLUR2/3 ANTAGONIST LY341495 REVERSED THE INHIBITORY EFFECT OF SUBEROYLANILIDE HYDROXAMIC ACID ON THE STRESS-INDUCED VISCERAL HYPERSENSITIVITY. IN SURPRISING CONTRAST, STRESS AND/OR SUBEROYLANILIDE HYDROXAMIC ACID HAD NO EFFECT ON SPINAL NMDA RECEPTOR EXPRESSION OR FUNCTION. THESE DATA REVEAL HISTONE MODIFICATION MODULATES MGLUR2/3 EXPRESSION IN THE SPINAL CORD TO ATTENUATE STRESSINDUCED VISCERAL HYPERSENSITIVITY. HDAC INHIBITORS MAY PROVIDE A POTENTIAL APPROACH TO RELIEVE VISCERAL HYPERSENSITIVITY ASSOCIATED WITH IRRITABLE BOWEL SYNDROME.	2016	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
12  2321  38 EPIGENETIC REGULATION OF GENES THAT MODULATE CHRONIC STRESS-INDUCED VISCERAL PAIN IN THE PERIPHERAL NERVOUS SYSTEM. BACKGROUND & AIMS: CHRONIC STRESS ALTERS THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS, INCREASES GUT MOTILITY, AND INCREASES THE PERCEPTION OF VISCERAL PAIN. WE INVESTIGATED WHETHER EPIGENETIC MECHANISMS REGULATE CHRONIC STRESS-INDUCED VISCERAL PAIN IN THE PERIPHERAL NERVOUS SYSTEMS OF RATS. METHODS: MALE RATS WERE SUBJECTED TO 1 HOUR OF WATER AVOIDANCE STRESS EACH DAY, OR GIVEN DAILY SUBCUTANEOUS INJECTIONS OF CORTICOSTERONE, FOR 10 CONSECUTIVE DAYS. L4-L5 AND L6-S2 DORSAL ROOT GANGLIA (DRG) WERE COLLECTED AND COMPARED BETWEEN STRESSED AND CONTROL RATS (PLACED FOR 1 HOUR EACH DAY IN A TANK WITHOUT WATER). LEVELS OF CANNABINOID RECEPTOR 1 (CNR1), DNA (CYTOSINE-5-)-METHYLTRANSFERASE 1 (DNMT1), TRANSIENT RECEPTOR POTENTIAL VANILLOID TYPE 1 (TRPV1), AND EP300 WERE KNOCKED DOWN IN DRG NEURONS IN SITU WITH SMALL INTERFERING RNAS. WE MEASURED DNA METHYLATION AND HISTONE ACETYLATION AT GENES ENCODING THE GLUCOCORTICOID RECEPTOR (NR3C1), CNR1, AND TRPV1. VISCERAL PAIN WAS MEASURED IN RESPONSE TO COLORECTAL DISTENTION. RESULTS: CHRONIC STRESS WAS ASSOCIATED WITH INCREASED METHYLATION OF THE NR3C1 PROMOTER AND REDUCED EXPRESSION OF THIS GENE IN L6-S2, BUT NOT L4-L5, DRGS. STRESS ALSO WAS ASSOCIATED WITH UP-REGULATION IN DNMT1-ASSOCIATED METHYLATION OF THE CNR1 PROMOTER AND DOWN-REGULATION OF GLUCOCORTICOID-RECEPTOR-MEDIATED EXPRESSION OF CNR1 IN L6-S2, BUT NOT L4-L5, DRGS. CONCURRENTLY, CHRONIC STRESS INCREASED EXPRESSION OF THE HISTONE ACETYLTRANSFERASE EP300 AND INCREASED HISTONE ACETYLATION AT THE TRPV1 PROMOTER AND EXPRESSION OF THE TRPV1 RECEPTOR IN L6-S2 DRG NEURONS. KNOCKDOWN OF DNMT1 AND EP300 IN L6-S2 DRG NEURONS OF RATS REDUCED DNA METHYLATION AND HISTONE ACETYLATION, RESPECTIVELY, AND PREVENTED CHRONIC STRESS-INDUCED INCREASES IN VISCERAL PAIN. CONCLUSIONS: CHRONIC STRESS INCREASES DNA METHYLATION AND HISTONE ACETYLATION OF GENES THAT REGULATE VISCERAL PAIN SENSATION IN THE PERIPHERAL NERVOUS SYSTEM OF RATS. BLOCKING EPIGENETIC REGULATORY PATHWAYS IN SPECIFIC REGIONS OF THE SPINAL CORD MIGHT BE DEVELOPED TO TREAT PATIENTS WITH CHRONIC ABDOMINAL PAIN.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
13  6559  25 TRANSGENERATIONAL INFLUENCE OF PARENTAL MORPHINE EXPOSURE ON PAIN PERCEPTION, ANXIETY-LIKE BEHAVIOR AND PASSIVE AVOIDANCE MEMORY AMONG MALE AND FEMALE OFFSPRING OF WISTAR RATS. ACCUMULATING EVIDENCE SUGGESTS THAT EPIGENETIC MECHANISMS PLAY AN IMPORTANT ROLE IN THE FORMATION AND MAINTENANCE OF MEMORY WITHIN THE BRAIN. MOREOVER, THE EFFECT OF PARENTAL DRUG-EXPOSURE BEFORE GESTATION ON BEHAVIORAL STATE OF OFFSPRING HAS BEEN LITTLE STUDIED. THE MAIN OBJECTIVE OF THE CURRENT STUDY IS TO EVALUATE THE EFFECT OF PARENTAL MORPHINE EXPOSURE ON AVOIDANCE MEMORY, MORPHINE PREFERENCE AND ANXIETY-LIKE BEHAVIOR OF OFFSPRING. THE TOTAL OF 32 MALES AND 32 FEMALES WERE USED FOR MATING. THE ANIMALS WERE TREATED WITH MORPHINE. THE OFFSPRING ACCORDING TO THEIR PARENTAL MORPHINE TREATMENT WAS DIVIDED INTO FOUR GROUPS (N=16) INCLUDING PATERNALLY TREATED, MATERNALLY TREATED, BOTH OF PARENTS TREATED AND NAIVE ANIMALS. THE PAIN PERCEPTION, ANXIETY-LIKE BEHAVIOR, AND AVOIDANCE MEMORY WERE EVALUATED IN THE OFFSPRING. IN THE CURRENT STUDY, THE TOTAL OF 256 OFFSPRING WAS USED FOR THE EXPERIMENTS (4 TASKS X 4 GROUPS OF OFFSPRING X 8 FEMALE OFFSPRING X 8 MALE OFFSPRING). THE FINDING REVEALED THAT THE AVOIDANCE MEMORY AND VISCERAL PAIN WERE REDUCED SIGNIFICANTLY IN MALE AND FEMALE OFFSPRING WITH AT LEAST ONE MORPHINE-TREATED PARENT. MOREOVER, ANXIETY-LIKE BEHAVIOR WAS REDUCED SIGNIFICANTLY IN THE MALE OFFSPRING WITH AT LEAST ONE MORPHINE-TREATED PARENT. WHILE ANXIETY-LIKE BEHAVIOR WAS INCREASED SIGNIFICANTLY IN FEMALE OFFSPRING THAT WERE TREATED BY MORPHINE EITHER MATERNALLY OR BOTH OF PARENTS. THE DATA REVEALED THAT THE ENDOGENOUS OPIOID SYSTEM MAY BE ALTERED IN THE OFFSPRING OF MORPHINE-TREATED PARENT(S), AND EPIGENETIC ROLE COULD BE IMPORTANT. HOWEVER, ANALYSIS OF VARIANCE SIGNIFIED THE IMPORTANT ROLE OF MATERNAL INHERITANCE.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
14  2358  25 EPIGENETIC REGULATION OF RAC1 INDUCES SYNAPTIC REMODELING IN STRESS DISORDERS AND DEPRESSION. DEPRESSION INDUCES STRUCTURAL AND FUNCTIONAL SYNAPTIC PLASTICITY IN BRAIN REWARD CIRCUITS, ALTHOUGH THE MECHANISMS PROMOTING THESE CHANGES AND THEIR RELEVANCE TO BEHAVIORAL OUTCOMES ARE UNKNOWN. TRANSCRIPTIONAL PROFILING OF THE NUCLEUS ACCUMBENS (NAC) FOR RHO GTPASE-RELATED GENES, WHICH ARE KNOWN REGULATORS OF SYNAPTIC STRUCTURE, REVEALED A SUSTAINED REDUCTION IN RAS-RELATED C3 BOTULINUM TOXIN SUBSTRATE 1 (RAC1) EXPRESSION AFTER CHRONIC SOCIAL DEFEAT STRESS. THIS WAS ASSOCIATED WITH A REPRESSIVE CHROMATIN STATE SURROUNDING THE PROXIMAL PROMOTER OF RAC1. INHIBITION OF CLASS 1 HISTONE DEACETYLASES (HDACS) WITH MS-275 RESCUED BOTH THE DECREASE IN RAC1 TRANSCRIPTION AFTER SOCIAL DEFEAT STRESS AND DEPRESSION-RELATED BEHAVIOR, SUCH AS SOCIAL AVOIDANCE. WE FOUND A SIMILAR REPRESSIVE CHROMATIN STATE SURROUNDING THE RAC1 PROMOTER IN THE NAC OF SUBJECTS WITH DEPRESSION, WHICH CORRESPONDED WITH REDUCED RAC1 TRANSCRIPTION. VIRAL-MEDIATED REDUCTION OF RAC1 EXPRESSION OR INHIBITION OF RAC1 ACTIVITY IN THE NAC INCREASES SOCIAL DEFEAT-INDUCED SOCIAL AVOIDANCE AND ANHEDONIA IN MICE. CHRONIC SOCIAL DEFEAT STRESS INDUCES THE FORMATION OF STUBBY EXCITATORY SPINES THROUGH A RAC1-DEPENDENT MECHANISM INVOLVING THE REDISTRIBUTION OF SYNAPTIC COFILIN, AN ACTIN-SEVERING PROTEIN DOWNSTREAM OF RAC1. OVEREXPRESSION OF CONSTITUTIVELY ACTIVE RAC1 IN THE NAC OF MICE AFTER CHRONIC SOCIAL DEFEAT STRESS REVERSES DEPRESSION-RELATED BEHAVIORS AND PRUNES STUBBY SPINES. TAKEN TOGETHER, OUR DATA IDENTIFY EPIGENETIC REGULATION OF RAC1 IN THE NAC AS A DISEASE MECHANISM IN DEPRESSION AND REVEAL A FUNCTIONAL ROLE FOR RAC1 IN RODENTS IN REGULATING STRESS-RELATED BEHAVIORS.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
15  6108  33 THE ENRICHED ENVIRONMENT AMELIORATES CHRONIC UNPREDICTABLE MILD STRESS-INDUCED DEPRESSIVE-LIKE BEHAVIORS AND COGNITIVE IMPAIRMENT BY ACTIVATING THE SIRT1/MIR-134 SIGNALING PATHWAY IN HIPPOCAMPUS. BACKGROUND: CHRONIC UNPREDICTABLE MILD STRESS (CUMS) IS AN IMPORTANT RISK FACTOR FOR DEPRESSION AND COGNITIVE DEFICITS IN HUMANS. ENRICHED ENVIRONMENT (EE) SHOWED A BENEFICIAL EFFECT ON DEPRESSION AND COGNITION BY ENHANCING BRAIN DERIVED NEUROTROPHIC FACTOR (BDNF) EXPRESSION AND SYNAPTIC PLASTICITY. HOWEVER, IT IS STILL NOT CLEARLY UNDERSTOOD WHETHER AN EPIGENETIC MECHANISM IS INVOLVED IN THE BDNF MODULATION AND SYNAPTIC PLASTICITY THAT OCCURS AFTER EE TREATMENT FOR THE DEPRESSIVE-LIKE BEHAVIORS AND COGNITIVE DEFICITS ELICITED BY CUMS. IN THIS STUDY, WE INVESTIGATED THE POSSIBLE MECHANISM OF THE NEUROPROTECTIVE EFFECT OF EE. METHODS: ALL RATS WERE EXPOSED TO THE 5-WEEK CUMS PROCEDURE EXCEPT THE CONTROL GROUP. AFTER CUMS PROCEDURE, SOME RATS WERE STEREOTAXICALLY INJECTED WITH SIRT1 PHARMACOLOGIC INHIBITOR EX527 OR SIRT1 KNOCKING DOWN LENTIVIRUS (SH-SIRT1) IN THE HIPPOCAMPUS FOLLOWED BY EE TREATMENT FOR 3 WEEKS. OTHER RATS WERE DIRECTLY SUBJECTED TO EE TREATMENT WITHOUT STEREOTAXIC INJECTION. BEHAVIORAL TESTS WERE USED TO APPRAISE DEPRESSION AND COGNITION AFTER EE TREATMENT. THEN EPIGENETIC MOLECULES, SYNAPTIC PROTEINS, DENDRITIC SPINE DENSITY AND BRANCHES, AND SYNAPTIC MORPHOLOGY OF THE DORSAL HIPPOCAMPUS WERE DETERMINED. RESULTS: WE FOUND THAT CUMS INDUCED DEPRESSIVE-LIKE BEHAVIORS INCLUDING DECREASED SUCROSE PREFERENCE RATIO, PROLONGED IMMOBILITY AND REDUCED LOCOMOTOR AND EXPLORATORY ACTIVITY; COGNITIVE DEFICITS INCLUDING SPATIAL LEARNING AND MEMORY IMPAIRMENT; REDUCED DENDRITIC SPINE DENSITY AND NUMBER OF BRANCHES; THINNED POSTSYNAPTIC DENSITY; DOWNREGULATED SIRT1/MICRORNA-134 PATHWAY, DECREASED BDNF AND SYNAPTIC PROTEINS INCLUDING SYNAPTOPHYSIN (SYN) AND POSTSYNAPTIC DENSITY PROTEIN 95 (PSD95) EXPRESSION IN THE HIPPOCAMPUS. HOWEVER, THE CUMS-INDUCED DEPRESSIVE-LIKE BEHAVIORS, COGNITIVE DEFICITS, DENDRITIC SPINE DENSITY AND BRANCH NUMBER REDUCTION, POSTSYNAPTIC DENSITY THINNING, SIRT1/MICRORNA-134 PATHWAY DOWNREGULATION, BDNF AND SYNAPTIC PROTEINS REDUCTION, INCLUDING SYNAPTOPHYSIN (SYN) AND POSTSYNAPTIC DENSITY PROTEIN 95 (PSD95), WERE REVERSED BY EE TREATMENT. HOWEVER, DEPRESSIVE-LIKE BEHAVIORS AND COGNITIVE DEFICITS WERE OBSERVED AGAIN IN RATS SUBJECTED TO STEREOTAXIC INJECTION WITH EX527 OR SH-SIRT1. FURTHERMORE, THIS STUDY ALSO FOUND THAT SIRT1/MICRORNA-134 REGULATES THE DOWNSTREAM MOLECULES BDNF, AND THE SYNAPTIC PROTEINS SYN AND PSD95 IN PRIMARY CULTURED HIPPOCAMPAL NEURONS. CONCLUSIONS: THIS STUDY PROVIDES EVIDENCE FOR THE NEUROPROTECTIVE ROLE OF EE ON DEPRESSION AND COGNITIVE DEFICITS BY ACTIVATING THE SIRT1/MICRORNA-134 PATHWAY, WHICH ACCOUNTS FOR THE REGULATION OF SYNAPTIC PROTEINS, INCLUDING BDNF, PSD95 AND SYN, DENDRITIC REMODELING AND ULTRASTRUCTURE CHANGES OF SYNAPSES IN THE HIPPOCAMPUS.	2019	
                                                                                                                                            
16  3318  39 HISTONE ACETYLATION AND EXPRESSION OF MONO-AMINERGIC TRANSMITTERS SYNTHETASES INVOLVED IN CUS-INDUCED DEPRESSIVE RATS. HISTONE ACETYLATION HAS BEEN LINKED TO DEPRESSION, THE ETIOLOGY OF WHICH INVOLVES MANY FACTORS SUCH AS GENETICS, ENVIRONMENTS, AND EPIGENETICS. THE AIM OF THE PRESENT STUDY WAS TO INVESTIGATE WHETHER IT WAS ASSOCIATED WITH EPIGENETIC HISTONE MODIFICATION AND GENE EXPRESSION OF ENZYMES RESPONSIBLE FOR THE BIOSYNTHESIS OF NOREPINEPHRINE AND SEROTONIN IN RAT DEPRESSION MODEL INDUCED BY CHRONIC UNPREDICTABLE STRESS (CUS). EIGHT-WEEK-OLD MALE SPRAGUE-DAWLEY RATS WERE EXPOSED TO CUS OVER 28 DAYS. IT WAS SHOWN THAT THE CUS-INDUCED RATS DISPLAYED REMARKED ANXIETY- AND DEPRESSION-LIKE BEHAVIOR WITH WEAKENED LOCOMOTOR ACTIVITY IN OPEN FIELD TEST AND PROLONGED IMMOBILITY IN FORCED SWIMMING TEST. WESTERN BLOT REVEALED THAT CUS LED TO SIGNIFICANT DECREASE IN ACETYLATION OF H3 AT LYSINE 9 (K9) AND H4 AT LYSINE 12 (K12) WITH OBVIOUSLY INCREASING HISTONE DEACETYLASES 5 (HDAC5) EXPRESSION IN HIPPOCAMPUS OF CUS-INDUCED RATS. MEANWHILE, THERE WAS AN OBVIOUSLY DECREASED EXPRESSION OF TYROSINE HYDROXYLASE (TH) AND TRYPTOPHAN HYDROXYLASE (TPH) BOTH AT PROTEIN AND MRNA LEVELS. ADMINISTRATION OF SODIUM VALPROATE (VPA), A HISTONE DEACETYLASE 5 (HDAC5) INHIBITOR, NOT ONLY SIGNIFICANTLY RELIEVED THE ANXIETY- AND DEPRESSION-LIKE BEHAVIORS OF CUS-INDUCED RATS BUT ALSO CLEARLY BLUNTED DECREASE OF H3(K9) AND H4(K12) ACETYLATION AND EXPRESSION OF TH AND TPH, AND PREVENTED INCREASE OF HDAC5 EXPRESSION. THE RESULTS INDICATE THAT THERE EXISTS POSSIBLE INTERRELATION BETWEEN TH AND TPH GENE EXPRESSION AND EPIGENETIC HISTONE ACETYLATION IN CUS-INDUCED DEPRESSIVE RATS, WHICH AT LEAST PARTLY CONTRIBUTES TO THE ETIOLOGY OF DEPRESSION.	2014	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
17  5559  28 ROLE OF HIPPOCAMPAL CIRCKCNK9 IN VISCERAL HYPERSENSITIVITY AND ANXIETY COMORBIDITY OF IRRITABLE BOWEL SYNDROME. IRRITABLE BOWEL SYNDROME (IBS) IS A COMMON GASTROINTESTINAL DISORDER CHARACTERIZED BY RECURRENT VISCERAL PAIN AND ALTERED BOWEL HABITS (DIARRHEA OR CONSTIPATION). HOWEVER, THE MOLECULAR AND PATHOLOGICAL MECHANISMS ARE POORLY UNDERSTOOD. THIS STUDY FOUND NEONATAL COLORECTAL DISTENSION TO INDUCE VISCERAL HYPERSENSITIVITY AND ANXIETY. THE EXPRESSION OF HIPPOCAMPAL CIRCKCNK9, A NOVEL CIRCRNA, WAS SIGNIFICANTLY INCREASED IN IBS-LIKE RATS. INTERESTINGLY, CA1 SHCIRCKCNK9 TREATMENT INHIBITED LONG-TERM POTENTIATION (LTP) AND ALLEVIATED VISCERAL HYPERSENSITIVITY AND ANXIETY IN IBS-LIKE RATS, WHEREAS OVEREXPRESSION OF CA1 CIRCKCNK9 INDUCED LTP, VISCERAL HYPERSENSITIVITY, AND ANXIETY IN CONTROLS. SEVERAL EXPERIMENTS INDICATED THAT INCREASED CA1 CIRCKCNK9 ACTED AS A MIR-124-3P SPONGE, WHICH RESULTED IN THE INHIBITORY EFFECT OF MIR-124-3P ON GENE SILENCING. THERE WAS A NEGATIVE CORRELATION BETWEEN CIRCKCNK9 AND MIR-124-3P EXPRESSION. AS EXPECTED, CA1 ADMINISTRATION OF AGOMIR-124-3P DECREASED CA1 LTP, VISCERAL HYPERSENSITIVITY, AND ANXIETY IN THE IBS-LIKE RATS. IN CONTRAST, CA1 TREATMENT WITH ANTAGOMIR-124-3P INDUCED LTP, VISCERAL HYPERSENSITIVITY, AND ANXIETY IN THE CONTROLS. FURTHERMORE, BIOINFORMATIC ANALYSIS AND EXPERIMENTAL DATA SHOWED THAT EZH2 IS A CIRCKCNK9/MIR-124-3P TARGET GENE, AND INCREASED EZH2 EXPRESSION WAS INVOLVED IN VISCERAL HYPERSENSITIVITY AND ANXIETY IN IBS-LIKE RATS BY ENHANCING HIPPOCAMPAL SYNAPTIC PLASTICITY. IN CONCLUSION, EARLY LIFE STRESS INDUCES INCREASED EXPRESSION OF CIRCKCNK9 IN THE CA1 OF IBS-LIKE RATS. INCREASED CIRCKCNK9 EXPRESSION REGULATES SYNAPTIC TRANSMISSION AND ENHANCES LTP, LEADING TO VISCERAL HYPERSENSITIVITY AND ANXIETY IN IBS-LIKE RATS. THE UNDERLYING CIRCKCNK9 SIGNALING PATHWAY IS MIR124-3P/EZH2. INCREASED CIRCKCNK9 REINFORCES ITS SPONGING OF MIR124-3P AND STRONGLY SUPPRESSES MIR124-3P ACTIVITY, RESULTING IN INCREASED EXPRESSION OF THE TARGET GENE EZH2. THIS STUDY PROVIDES A NEW EPIGENETIC MECHANISM FOR VISCERAL HYPERSENSITIVITY AND ANXIETY IN IBS-LIKE RATS.	2022	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
18    69  28 A MEDIAL PREFRONTAL CORTEX-NUCLEUS ACUMENS CORTICOTROPIN-RELEASING FACTOR CIRCUITRY FOR NEUROPATHIC PAIN-INCREASED SUSCEPTIBILITY TO OPIOID REWARD. RECENT STUDIES HAVE SHOWN THAT PERSISTENT PAIN FACILITATES THE RESPONSE TO MORPHINE REWARD. HOWEVER, THE CIRCUIT MECHANISM UNDERLYING THIS PROCESS REMAINS AMBIGUOUS. IN THIS STUDY, USING CHRONIC CONSTRICTION INJURY (CCI) OF THE SCIATIC NERVE IN MICE, WE FOUND THAT PERSISTENT NEUROPATHIC PAIN REDUCED THE MINIMUM NUMBER OF MORPHINE CONDITIONING SESSIONS REQUIRED TO INDUCE CONDITIONED PLACE PREFERENCE (CPP) BEHAVIOR. THIS DOSE OF MORPHINE HAD NO EFFECT ON THE PAIN THRESHOLD. IN THE MEDIAL PREFRONTAL CORTEX (MPFC), WHICH IS INVOLVED IN BOTH PAIN AND EMOTION PROCESSING, CORTICOTROPIN-RELEASING FACTOR (CRF) EXPRESSING NEURONAL ACTIVITY WAS INCREASED IN CCI MICE. CHEMOGENETIC INHIBITION OF MPFC CRF NEURONS REVERSED CCI-INDUCED MORPHINE CPP FACILITATION. FURTHERMORE, THE NUCLEUS ACUMENS (NAC) RECEIVED MPFC CRF FUNCTIONAL PROJECTIONS THAT EXERTED EXCITATORY EFFECTS ON NAC NEURONS. OPTOGENETIC INHIBITION OF MPCF NEURONAL TERMINALS OR LOCAL INFUSION OF THE CRF RECEPTOR 1 (CRFR1) ANTAGONIST IN THE NAC RESTORED THE EFFECTS OF NEUROPATHIC PAIN ON MORPHINE-INDUCED CPP BEHAVIOR, BUT NOT IN NORMAL MICE. ON A MOLECULAR LEVEL, IN CCI MICE, CRFR1 PROTEIN EXPRESSION WAS INCREASED IN THE NAC BY A HISTONE DIMETHYLTRANSFERASE G9A-MEDIATED EPIGENETIC MECHANISM. LOCAL G9A KNOCKDOWN INCREASED THE EXPRESSION OF CRFR1 AND MIMICKED CCI-INDUCED HYPERSENSITIVITY TO ACQUIRING MORPHINE CPP. TAKEN TOGETHER, THESE FINDINGS DEMONSTRATE A PREVIOUSLY UNKNOWN AND SPECIFIC MPFC CRF ENGAGEMENT OF NAC NEURONAL CIRCUITS, THE SENSITIZATION OF WHICH FACILITATES BEHAVIORAL RESPONSES TO MORPHINE REWARD IN NEUROPATHIC PAIN STATES VIA CRFR1S.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         
19  2482  34 EPIGENETIC UPREGULATION OF METABOTROPIC GLUTAMATE RECEPTOR 2 IN THE SPINAL CORD ATTENUATES OESTROGEN-INDUCED VISCERAL HYPERSENSITIVITY. OBJECTIVE: EPIGENETIC MECHANISMS ARE POTENTIAL TARGETS TO RELIEVE SOMATIC PAIN. HOWEVER, LITTLE IS KNOWN WHETHER EPIGENETIC REGULATION INTERFERES WITH VISCERAL PAIN. PREVIOUS STUDIES SHOW THAT OESTROGEN FACILITATES VISCERAL PAIN. THIS STUDY AIMED TO DETERMINE WHETHER HISTONE HYPERACETYLATION IN THE SPINAL CORD COULD ATTENUATE OESTROGEN-FACILITATED VISCERAL PAIN. DESIGN: THE EFFECT OF THE HISTONE DEACETYLASE INHIBITOR SUBEROYLANILIDE HYDROXAMIC ACID (SAHA) ON THE MAGNITUDE OF THE VISCEROMOTOR RESPONSE (VMR) TO COLORECTAL DISTENTION WAS EXAMINED IN OVARIECTOMISED RATS WITH/WITHOUT OESTROGEN REPLACEMENT. AN ADDITIONAL INTERACTION WITH THE METABOTROPIC GLUTAMATE RECEPTOR 2/3 (MGLUR2/3) ANTAGONIST LY341495 WAS TESTED. THE LEVELS OF ACETYLATED HISTONE AND MGLUR2 MRNA AND PROTEIN WERE ANALYSED. THE BINDING OF ACETYLATED H3 AND OESTROGEN RECEPTOR ALPHA (ERALPHA) TO THE GRM2 PROMOTER WAS MEASURED BY CHROMATIN IMMUNOPRECIPITATION COUPLED WITH QPCR. RESULTS: IN OVARIECTOMISED RATS, 17BETA-ESTRADIOL (E2), BUT NOT SAFFLOWER OIL, INCREASED THE MAGNITUDE OF THE VMR TO COLORECTAL DISTENTION. SAHA ATTENUATED THE E2-FACILITATED VMR, BUT HAD NO EFFECT IN SAFFLOWER OIL-TREATED RATS. SUBSEQUENT SPINAL ADMINISTRATION OF LY341495 REVERSED THE ANTINOCICEPTIVE EFFECT OF SAHA IN E2 RATS. IN ADDITION, SAHA INCREASED MGLUR2 MRNA AND PROTEIN IN THE SPINAL DORSAL HORN FOLLOWING E2, BUT NOT VEHICLE, TREATMENT. IN CONTRAST, NEITHER E2 NOR SAHA ALONE ALTERED MGLUR2 MRNA. SAHA INCREASED BINDING OF H3K9AC AND ERALPHA TO THE SAME REGIONS OF THE GRM2 PROMOTER IN E2-SAHA-TREATED ANIMALS. CONCLUSIONS: HISTONE HYPERACETYLATION IN THE SPINAL CORD ATTENUATES THE PRONOCICEPTIVE EFFECTS OF OESTROGEN ON VISCERAL SENSITIVITY, SUGGESTING THAT EPIGENETIC REGULATION MAY BE A POTENTIAL APPROACH TO RELIEVE VISCERAL PAIN.	2015	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
20  1808  39 EFFECTS OF ADOLESCENT SOCIAL STRESS AND ANTIDEPRESSANT TREATMENT ON COGNITIVE INFLEXIBILITY AND BDNF EPIGENETIC MODIFICATIONS IN THE MPFC OF ADULT MICE. ADOLESCENT SOCIAL STRESS (ASS) CAN INCREASE SUSCEPTIBILITY TO DEPRESSION IN ADULTHOOD. HOWEVER, THE UNDERLYING PSYCHOLOGICAL AND NEURAL MECHANISMS REMAIN UNCLEAR. CORTICALLY MEDIATED COGNITIVE DYSFUNCTIONS ARE INCREASINGLY RECOGNIZED AS AN INDEPENDENT AND IMPORTANT RISK FACTOR OF DEPRESSION. USING SOCIAL DEFEAT STRESS, A CLASSICAL ANIMAL MODEL OF DEPRESSION, OUR PREVIOUS STUDIES FOUND THAT MICE SUBJECTED TO THIS FORM OF STRESS DURING EARLY ADOLESCENCE DISPLAYED COGNITIVE INFLEXIBILITY (CI) IN ADULTHOOD. THIS CHANGE WAS ACCOMPANIED BY A DOWN-REGULATION OF BDNF GENE EXPRESSION IN THE MEDIAL PREFRONTAL CORTEX (MPFC); THIS GENE ENCODES A KEY MOLECULE INVOLVED IN DEPRESSION AND ANTIDEPRESSANT ACTION. IN THE PRESENT PAPER, WE IDENTIFIED EPIGENETIC MODIFICATION OF BDNF AS A POSSIBLE MECHANISM UNDERLYING THE BEHAVIORAL AND MOLECULAR CHANGES. ASS INDUCED A SET OF DEPRESSIVE PHENOTYPES, INCLUDING INCREASED SOCIAL AVOIDANCE AND CI, AS WELL AS REDUCED LEVELS OF TOTAL BDNF AND ISOFORM IV BUT NOT ISOFORM I OR VI TRANSCRIPTS IN THE MPFC. IN PARALLEL WITH CHANGES IN BDNF GENE EXPRESSION, PREVIOUSLY STRESSED ADULT MICE SHOWED INCREASED LEVELS OF DIMETHYLATION OF HISTONE H3 AT LYSINE K9 (H3K9ME2) IMMEDIATELY DOWNSTREAM OF THE BDNF IV PROMOTER. ON THE OTHER HAND, NO DIFFERENCES WERE FOUND IN TRIMETHYLATION OF HISTONE H3 AT LYSINE K4 (H3K4ME3) OR IN ACETYLATION OF HISTONE H3 AT LYSINE K9 (H3K9AC) OR AT K4 (H3K4AC) IN THE BDNF IV PROMOTER. LIKEWISE, NO ALTERATIONS WERE FOUND IN DNA METHYLATION OF THE BDNF IV PROMOTER. ADDITIONALLY, TREATMENT WITH THE CHRONIC ANTIDEPRESSANT TRANYLCYPROMINE REVERSED BDNF EPIGENETIC CHANGES AND RELATED GENE TRANSCRIPTION WHILE ALSO REVERSING CI, BUT NOT SOCIAL AVOIDANCE, IN PREVIOUSLY STRESSED ADULT MICE. THESE RESULTS SUGGEST THAT EPIGENETIC CHANGES TO THE BDNF GENE IN THE MPFC AFTER ADOLESCENT SOCIAL ADVERSITY MAY BE INVOLVED IN THE REGULATION OF COGNITIVE DYSFUNCTION IN DEPRESSION AND ANTIDEPRESSANT ACTION IN ADULTHOOD.	2018