1 1220 105 CRISPR/CAS9-BASED MUTAGENESIS OF HISTONE H3.1 IN SPINAL DYNORPHINERGIC NEURONS ATTENUATES THERMAL SENSITIVITY IN MICE. BURN INJURY IS A TRAUMA RESULTING IN TISSUE DEGRADATION AND SEVERE PAIN, WHICH IS PROCESSED FIRST BY NEURONAL CIRCUITS IN THE SPINAL DORSAL HORN. WE HAVE RECENTLY SHOWN THAT IN MICE, EXCITATORY DYNORPHINERGIC (PDYN) NEURONS PLAY A PIVOTAL ROLE IN THE RESPONSE TO BURN-INJURY-ASSOCIATED TISSUE DAMAGE VIA HISTONE H3.1 PHOSPHORYLATION-DEPENDENT SIGNALING. AS PDYN NEURONS WERE MOSTLY ASSOCIATED WITH MECHANICAL ALLODYNIA, THEIR INVOLVEMENT IN THERMONOCICEPTION HAD TO BE FURTHER ELUCIDATED. USING A CUSTOM-MADE AAV9_MUTH3.1 VIRUS COMBINED WITH THE CRISPR/CAS9 SYSTEM, HERE WE PROVIDE EVIDENCE THAT BLOCKING HISTONE H3.1 PHOSPHORYLATION AT POSITION SERINE 10 (S10) IN SPINAL PDYN NEURONS SIGNIFICANTLY INCREASES THE THERMAL NOCICEPTIVE THRESHOLD IN MICE. IN CONTRAST, NEITHER MECHANOSENSATION NOR ACUTE CHEMONOCICEPTION WAS AFFECTED BY THE TRANSGENIC MANIPULATION OF HISTONE H3.1. THESE RESULTS SUGGEST THAT BLOCKING RAPID EPIGENETIC TAGGING OF S10H3 IN SPINAL PDYN NEURONS ALTERS ACUTE THERMOSENSATION AND THUS EXPLAINS THE INVOLVEMENT OF PDYN CELLS IN THE IMMEDIATE RESPONSE TO BURN-INJURY-ASSOCIATED TISSUE DAMAGE.	2022	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
2 5063  37 PHOSPHORYLATED HISTONE 3 AT SERINE 10 IDENTIFIES ACTIVATED SPINAL NEURONS AND CONTRIBUTES TO THE DEVELOPMENT OF TISSUE INJURY-ASSOCIATED PAIN. TRANSCRIPTIONAL CHANGES IN SUPERFICIAL SPINAL DORSAL HORN NEURONS (SSDHN) ARE ESSENTIAL IN THE DEVELOPMENT AND MAINTENANCE OF PROLONGED PAIN. EPIGENETIC MECHANISMS INCLUDING POST-TRANSLATIONAL MODIFICATIONS IN HISTONES ARE PIVOTAL IN REGULATING TRANSCRIPTION. HERE, WE REPORT THAT PHOSPHORYLATION OF SERINE 10 (S10) IN HISTONE 3 (H3) SPECIFICALLY OCCURS IN A GROUP OF RAT SSDHN FOLLOWING THE ACTIVATION OF NOCICEPTIVE PRIMARY SENSORY NEURONS BY BURN INJURY, CAPSAICIN APPLICATION OR SUSTAINED ELECTRICAL ACTIVATION OF NOCICEPTIVE PRIMARY SENSORY NERVE FIBRES. IN CONTRAST, BRIEF THERMAL OR MECHANICAL NOCICEPTIVE STIMULI, WHICH FAIL TO INDUCE TISSUE INJURY OR INFLAMMATION, DO NOT PRODUCE THE SAME EFFECT. BLOCKING N-METHYL-D-ASPARTATE RECEPTORS OR ACTIVATION OF EXTRACELLULAR SIGNAL-REGULATED KINASES 1 AND 2, OR BLOCKING OR DELETING THE MITOGEN- AND STRESS-ACTIVATED KINASES 1 AND 2 (MSK1/2), WHICH PHOSPHORYLATE S10 IN H3, INHIBIT UP-REGULATION IN PHOSPHORYLATED S10 IN H3 (P-S10H3) AS WELL AS FOS TRANSCRIPTION, A DOWN-STREAM EFFECT OF P-S10H3. DELETING MSK1/2 ALSO INHIBITS THE DEVELOPMENT OF CARRAGEENAN-INDUCED INFLAMMATORY HEAT HYPERALGESIA IN MICE. WE PROPOSE THAT P-S10H3 IS A NOVEL MARKER FOR NOCICEPTIVE PROCESSING IN SSDHN WITH HIGH RELEVANCE TO TRANSCRIPTIONAL CHANGES AND THE DEVELOPMENT OF PROLONGED PAIN.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
3 2470  33 EPIGENETIC TRANSCRIPTIONAL ACTIVATION OF MONOCYTE CHEMOTACTIC PROTEIN 3 CONTRIBUTES TO LONG-LASTING NEUROPATHIC PAIN. A MULTIPLEX ANALYSIS FOR PROFILING THE EXPRESSION OF CANDIDATE GENES ALONG WITH EPIGENETIC MODIFICATION MAY LEAD TO A BETTER UNDERSTANDING OF THE COMPLEX MACHINERY OF NEUROPATHIC PAIN. IN THE PRESENT STUDY, WE FOUND THAT PARTIAL SCIATIC NERVE LIGATION MOST REMARKABLY INCREASED THE EXPRESSION OF MONOCYTE CHEMOTACTIC PROTEIN 3 (MCP-3, KNOWN AS CCL7) A TOTAL OF 33 541 GENES IN THE SPINAL CORD, WHICH LASTED FOR 4 WEEKS. THIS INCREASE IN MCP-3 GENE TRANSCRIPTION WAS ACCOMPANIED BY THE DECREASED TRIMETHYLATION OF HISTONE H3 AT LYS27 AT THE MCP-3 PROMOTER. THE INCREASED MCP-3 EXPRESSION ASSOCIATED WITH ITS EPIGENETIC MODIFICATION OBSERVED IN THE SPINAL CORD WAS ALMOST ABOLISHED IN INTERLEUKIN 6 KNOCKOUT MICE WITH PARTIAL SCIATIC NERVE LIGATION. CONSISTENT WITH THESE FINDINGS, A SINGLE INTRATHECAL INJECTION OF RECOMBINANT PROTEINS OF INTERLEUKIN 6 SIGNIFICANTLY INCREASED MCP-3 MESSENGER RNA WITH A DECREASE IN THE LEVEL OF LYS27 TRIMETHYLATION OF HISTONE H3 AT THE MCP-3 PROMOTER IN THE SPINAL CORD OF MICE. FURTHERMORE, DELETION OF THE C-C CHEMOKINE RECEPTOR TYPE 2 (CCR2) GENE, WHICH ENCODES A RECEPTOR FOR MCP-3, FAILED TO AFFECT THE ACCELERATION OF MCP-3 EXPRESSION IN THE SPINAL CORD AFTER PARTIAL SCIATIC NERVE LIGATION. A ROBUST INCREASE IN MCP-3 PROTEIN, WHICH LASTED FOR UP TO 2 WEEKS AFTER SURGERY, IN THE DORSAL HORN OF THE SPINAL CORD OF MICE WITH PARTIAL SCIATIC NERVE LIGATION WAS SEEN MOSTLY IN ASTROCYTES, BUT NOT MICROGLIA OR NEURONS. ON THE OTHER HAND, THE INCREASES IN BOTH MICROGLIA AND ASTROCYTES IN THE SPINAL CORD BY PARTIAL SCIATIC NERVE LIGATION WERE MOSTLY ABOLISHED IN INTERLEUKIN 6 KNOCKOUT MICE. MOREOVER, THIS INCREASE IN MICROGLIA WAS ALMOST ABOLISHED BY CCR2 GENE DELETION, WHEREAS THE INCREASE IN ASTROCYTES WAS NOT AFFECTED IN NERVE-LIGATED MICE THAT LACKED THE CCR2 GENE. WE ALSO FOUND THAT EITHER IN VIVO OR IN VITRO TREATMENT WITH MCP-3 CAUSED ROBUST MICROGLIA ACTIVATION. UNDER THESE CONDITIONS, INTRATHECAL ADMINISTRATION OF MCP-3 ANTIBODY SUPPRESSED THE INCREASE IN MICROGLIA WITHIN THE MOUSE SPINAL CORD AND NEUROPATHIC PAIN-LIKE BEHAVIOURS AFTER NERVE INJURY. WITH THE USE OF A FUNCTIONAL MAGNETIC RESONANCE IMAGING ANALYSIS, WE DEMONSTRATED THAT A SINGLE INTRATHECAL INJECTION OF MCP-3 INDUCED DRAMATIC INCREASES IN SIGNAL INTENSITY IN PAIN-RELATED BRAIN REGIONS. THESE FINDINGS SUGGEST THAT INCREASED MCP-3 EXPRESSION ASSOCIATED WITH INTERLEUKIN 6 DEPENDENT EPIGENETIC MODIFICATION AT THE MCP-3 PROMOTER AFTER NERVE INJURY, MOSTLY IN SPINAL ASTROCYTES, MAY SERVE TO FACILITATE ASTROCYTE-MICROGLIA INTERACTION IN THE SPINAL CORD AND COULD PLAY A CRITICAL ROLE IN THE NEUROPATHIC PAIN-LIKE STATE.	2013	

4 4861  31 ORGANIC ANION TRANSPORTER 1 IS AN HDAC4-REGULATED MEDIATOR OF NOCICEPTIVE HYPERSENSITIVITY IN MICE. PERSISTENT PAIN IS SUSTAINED BY MALADAPTIVE CHANGES IN GENE TRANSCRIPTION RESULTING IN ALTERED FUNCTION OF THE RELEVANT CIRCUITS; THERAPIES ARE STILL UNSATISFACTORY. THE EPIGENETIC MECHANISMS AND AFFECTED GENES LINKING NOCICEPTIVE ACTIVITY TO TRANSCRIPTIONAL CHANGES AND PATHOLOGICAL SENSITIVITY ARE UNCLEAR. HERE, WE FOUND THAT, AMONG SEVERAL HISTONE DEACETYLASES (HDACS), SYNAPTIC ACTIVITY SPECIFICALLY AFFECTS HDAC4 IN MURINE SPINAL CORD DORSAL HORN NEURONS. NOXIOUS STIMULI THAT INDUCE LONG-LASTING INFLAMMATORY HYPERSENSITIVITY CAUSE NUCLEAR EXPORT AND INACTIVATION OF HDAC4. THE DEVELOPMENT OF INFLAMMATION-ASSOCIATED MECHANICAL HYPERSENSITIVITY, BUT NEITHER ACUTE NOR BASAL SENSITIVITY, IS IMPAIRED BY THE EXPRESSION OF A CONSTITUTIVELY NUCLEAR LOCALIZED HDAC4 MUTANT. NEXT GENERATION RNA-SEQUENCING REVEALED AN HDAC4-REGULATED GENE PROGRAM COMPRISING MEDIATORS OF SENSITIZATION INCLUDING THE ORGANIC ANION TRANSPORTER OAT1, KNOWN FOR ITS RENAL TRANSPORT FUNCTION. USING PHARMACOLOGICAL AND MOLECULAR TOOLS TO MODULATE OAT1 ACTIVITY OR EXPRESSION, WE CAUSALLY LINK OAT1 TO PERSISTENT INFLAMMATORY HYPERSENSITIVITY IN MICE. THUS, HDAC4 IS A KEY EPIGENETIC REGULATOR THAT TRANSLATES NOCICEPTIVE ACTIVITY INTO SENSITIZATION BY REGULATING OAT1, WHICH IS A POTENTIAL TARGET FOR PAIN-RELIEVING THERAPIES.	2022	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
5 2785  37 EZH2 REGULATES SPINAL NEUROINFLAMMATION IN RATS WITH NEUROPATHIC PAIN. ALTERATION IN GENE EXPRESSION ALONG THE PAIN SIGNALING PATHWAY IS A KEY MECHANISM CONTRIBUTING TO THE GENESIS OF NEUROPATHIC PAIN. ACCUMULATING STUDIES HAVE SHOWN THAT EPIGENETIC REGULATION PLAYS A CRUCIAL ROLE IN NOCICEPTIVE PROCESS IN THE SPINAL DORSAL HORN. IN THIS PRESENT STUDY, WE INVESTIGATED THE ROLE OF ENHANCER OF ZESTE HOMOLOG-2 (EZH2), A SUBUNIT OF THE POLYCOMB REPRESSIVE COMPLEX 2, IN THE SPINAL DORSAL HORN IN THE GENESIS OF NEUROPATHIC PAIN IN RATS INDUCED BY PARTIAL SCIATIC NERVE LIGATION. EZH2 IS A HISTONE METHYLTRANSFERASE, WHICH CATALYZES THE METHYLATION OF HISTONE H3 ON K27 (H3K27), RESULTING IN GENE SILENCING. WE FOUND THAT LEVELS OF EZH2 AND TRI-METHYLATED H3K27 (H3K27TM) IN THE SPINAL DORSAL HORN WERE INCREASED IN RATS WITH NEUROPATHIC PAIN ON DAY 3 AND DAY 10 POST NERVE INJURIES. EZH2 WAS PREDOMINANTLY EXPRESSED IN NEURONS IN THE SPINAL DORSAL HORN UNDER NORMAL CONDITIONS. THE NUMBER OF NEURONS WITH EZH2 EXPRESSION WAS INCREASED AFTER NERVE INJURY. MORE STRIKINGLY, NERVE INJURY DRASTICALLY INCREASED THE NUMBER OF MICROGLIA WITH EZH2 EXPRESSION BY MORE THAN SEVENFOLD. INTRATHECAL INJECTION OF THE EZH2 INHIBITOR ATTENUATED THE DEVELOPMENT AND MAINTENANCE OF MECHANICAL AND THERMAL HYPERALGESIA IN RATS WITH NERVE INJURY. SUCH ANALGESIC EFFECTS WERE CONCURRENTLY ASSOCIATED WITH THE REDUCED LEVELS OF EZH2, H3K27TM, IBA1, GFAP, TNF-ALPHA, IL-1BETA, AND MCP-1 IN THE SPINAL DORSAL HORN IN RATS WITH NERVE INJURY. OUR RESULTS HIGHLY SUGGEST THAT TARGETING THE EZH2 SIGNALING PATHWAY COULD BE AN EFFECTIVE APPROACH FOR THE MANAGEMENT OF NEUROPATHIC PAIN.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
6 3833  37 INVOLVEMENT OF THE DYNORPHIN/KOR SYSTEM ON THE NOCICEPTIVE, EMOTIONAL AND COGNITIVE MANIFESTATIONS OF JOINT PAIN IN MICE. JOINT PAIN IS A MAJOR CLINICAL PROBLEM MAINLY ASSOCIATED TO OSTEOARTHRITIS, AND CHARACTERIZED BY ARTICULAR CARTILAGE DEGRADATION RESULTING IN A COMPLEX CHRONIC PAIN STATE THAT INCLUDES NOCICEPTIVE, EMOTIONAL AND COGNITIVE MANIFESTATIONS. MEMORY IMPAIRMENT, DEPRESSIVE- AND ANXIETY-LIKE SYMPTOMS HAVE BEEN REPORTED TO BE ASSOCIATED WITH CHRONIC PAIN, LEADING TO A DECREASE OF LIFE QUALITY. IN THIS STUDY, WE EVALUATED THE INVOLVEMENT OF THE ENDOGENOUS DYNORPHIN/KAPPA OPIOID RECEPTOR (KOR) SYSTEM ON THE NOCICEPTIVE, EMOTIONAL, COGNITIVE, NEUROCHEMICAL AND EPIGENETIC MANIFESTATIONS OF JOINT PAIN. THE MURINE MODEL OF MONOSODIUM IODOACETATE (MIA) WAS USED TO INDUCE JOINT PAIN IN KNOCKOUT MICE FOR KOR (KOR-KO), PRODYNORPHIN (PDYN-KO) AND THEIR WILD-TYPE (WT) LITTERMATES. KOR-KO AND PDYN-KO MICE DEVELOPED MECHANICAL ALLODYNIA AFTER INTRA-ARTICULAR INJECTION OF MIA. THIS ALLODYNIA WAS SIGNIFICANTLY INCREASED IN BOTH KOR-KO AND PDYN-KO WHEN COMPARED TO WT MICE. ACCORDINGLY, BOTH MUTANTS SHOWED INCREASED MICROGLIAL ACTIVATION ON THE LUMBAR SECTION OF THE SPINAL CORD AFTER MIA. THE EMOTIONAL RESPONSES WERE EVALUATED BY MEASURING ANXIETY-LIKE BEHAVIOUR IN THE ELEVATED PLUS MAZE AND ANHEDONIA AS DEPRESSIVE-LIKE BEHAVIOUR, AND COGNITIVE ALTERATIONS IN THE OBJECT RECOGNITION PARADIGM. EMOTIONAL AND COGNITIVE IMPAIRMENTS AFTER JOINT PAIN WERE DIFFERENTLY MODIFIED IN KOR-KO AND PDYN-KO MICE. ALTERATIONS OF CORTICOTROPIN-RELEASING FACTOR (CRF) ON THE AMYGDALA AND HIPPOCAMPUS AND DOWN REGULATION OF HISTONE 3 ACETYLATION ON THE AMYGDALA SUGGEST A POSSIBLE MECHANISM TO EXPLAIN THESE EMOTIONAL AND COGNITIVE MANIFESTATIONS. OUR RESULTS REVEAL A SPECIFIC INVOLVEMENT OF THE DYNORPHIN/KOR SYSTEM ON JOINT PAIN MANIFESTATIONS THAT ARE USUALLY ASSOCIATED TO OSTEOARTHRITIS.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
7 5851  37 SUBEROYLANILIDE HYDROXAMIC ACID TRIGGERS AUTOPHAGY BY INFLUENCING THE MTOR PATHWAY IN THE SPINAL DORSAL HORN IN A RAT NEUROPATHIC PAIN MODEL. HISTONE ACETYLATION LEVELS CAN BE UPREGULATED BY TREATING CELLS WITH HISTONE DEACETYLASE INHIBITORS (HDACIS), WHICH CAN INDUCE AUTOPHAGY. AUTOPHAGY FLUX IN THE SPINAL CORD OF RATS FOLLOWING THE LEFT FIFTH LUMBER SPINAL NERVE LIGATION (SNL) IS INVOLVED IN THE PROGRESSION OF NEUROPATHIC PAIN. SUBEROYLANILIDE HYDROXAMIC ACID (SAHA), ONE OF THE HDACIS CAN INTERFERE WITH THE EPIGENETIC PROCESS OF HISTONE ACETYLATION, WHICH HAS BEEN SHOWN TO EASE NEUROPATHIC PAIN. RECENT RESEARCH SUGGEST THAT SAHA CAN STIMULATE AUTOPHAGY VIA THE MAMMALIAN TARGET OF RAPAMYCIN (MTOR) PATHWAY IN SOME TYPES OF CANCER CELLS. HOWEVER, LITTLE IS KNOWN ABOUT THE ROLE OF SAHA AND AUTOPHAGY IN NEUROPATHIC PAIN AFTER NERVE INJURY. IN THE PRESENT STUDY, WE AIM TO INVESTIGATE AUTOPHAGY FLUX AND THE ROLE OF THE MTOR PATHWAY ON SPINAL CELLS AUTOPHAGY ACTIVATION IN NEUROPATHIC PAIN INDUCED BY SNL IN RATS THAT RECEIVED SAHA TREATMENT. AUTOPHAGY-RELATED PROTEINS AND MTOR OR ITS ACTIVE FORM WERE ASSESSED BY USING WESTERN BLOT, IMMUNOHISTOCHEMISTRY, DOUBLE IMMUNOFLUORESCENCE STAINING AND TRANSMISSION ELECTRON MICROSCOPY (TEM). WE FOUND THAT SAHA DECREASED THE PAW MECHANICAL WITHDRAWAL THRESHOLD (PMWT) OF THE LOWER COMPARED WITH SNL. AUTOPHAGY FLUX WAS MAINLY DISRUPTED IN THE ASTROCYTES AND NEURONAL CELLS OF THE SPINAL CORD DORSAL HORN ON POSTSURGICAL DAY 28 AND WAS REVERSED BY DAILY INTRATHECAL INJECTION OF SAHA (N = 100 NMOL/DAY OR N = 200 NMOL/DAY). SAHA ALSO DECREASED MTOR AND PHOSPHORYLATED MTOR (P-MTOR) EXPRESSION, ESPECIALLY P-MTOR EXPRESSION IN ASTROCYTES AND NEURONAL CELLS OF THE SPINAL DORSAL HORN. THESE RESULTS SUGGEST THAT SAHA ATTENUATES NEUROPATHIC PAIN AND CONTRIBUTES TO AUTOPHAGY FLUX IN ASTROCYTES AND NEURONAL CELLS OF THE SPINAL DORSAL HORN VIA THE MTOR SIGNALING PATHWAY.	2019	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
8 4742  25 NOVEL HISTONE MODIFICATIONS IN MICROGLIA DERIVED FROM A MOUSE MODEL OF CHRONIC PAIN. AS THE RESIDENT IMMUNE CELLS IN THE CENTRAL NERVOUS SYSTEM, MICROGLIA PLAY AN IMPORTANT ROLE IN THE MAINTENANCE OF ITS HOMEOSTASIS. DYSREGULATION OF MICROGLIA HAS BEEN ASSOCIATED WITH THE DEVELOPMENT AND MAINTENANCE OF CHRONIC PAIN. HOWEVER, THE RELEVANT MOLECULAR PATHWAYS REMAIN POORLY DEFINED. IN THIS STUDY, WE USED A MASS SPECTROMETRY-BASED PROTEOMIC APPROACH TO SCREEN POTENTIAL CHANGES OF HISTONE PROTEIN MODIFICATIONS IN MICROGLIA ISOLATED FROM THE BRAIN OF CONTROL AND CISPLATIN-INDUCED NEUROPATHIC PAIN ADULT C57BL/6J MALE MICE. WE IDENTIFIED SEVERAL NOVEL MICROGLIAL HISTONE MODIFICATIONS ASSOCIATED WITH PAIN, INCLUDING STATISTICALLY SIGNIFICANTLY DECREASED HISTONE H3.1 LYSINE 27 MONO-METHYLATION (H3.1K27ME1, 54.8% OF CONTROL) AND H3 LYSINE 56 TRI-METHYLATION (7.5% OF CONTROL), AS WELL AS A TREND SUGGESTING INCREASED H3 TYROSINE 41 NITRATION. WE FURTHER INVESTIGATED THE FUNCTIONAL ROLE OF H3.1K27ME1 AND FOUND THAT TREATMENT OF CULTURED MICROGLIAL CELLS FOR 4 CONSECUTIVE DAYS WITH 1-10 MUM OF NCDM-64, A POTENT AND SELECTIVE INHIBITOR OF LYSINE DEMETHYLASE 7A, AN ENZYME RESPONSIBLE FOR THE DEMETHYLATION OF H3K27ME1, DOSE-DEPENDENTLY ELEVATED ITS LEVELS WITH A GREATER THAN A TWO-FOLD INCREASE OBSERVED AT 10 MUM COMPARED TO VEHICLE-TREATED CONTROL CELLS. MOREOVER, PRETREATMENT OF MICE WITH NCDM-64 (10 OR 25 MG/KG/DAY, I.P.) PRIOR TO CISPLATIN TREATMENT PREVENTED THE DEVELOPMENT OF NEUROPATHIC PAIN IN MICE. THE IDENTIFICATION OF SPECIFIC CHROMATIN MARKS IN MICROGLIA ASSOCIATED WITH CHRONIC PAIN MAY YIELD CRITICAL INSIGHT INTO THE CONTRIBUTION OF MICROGLIA TO THE DEVELOPMENT AND MAINTENANCE OF PAIN, AND OPENS NEW AVENUES FOR THE DEVELOPMENT OF NOVEL NONOPIOID THERAPEUTICS FOR THE EFFECTIVE MANAGEMENT OF CHRONIC PAIN.	2022	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
9  804  30 CENTRAL ENDOTHELIN-1 CONFERS ANALGESIA BY TRIGGERING SPINAL NEURONAL HISTONE DEACETYLASE 5 (HDAC5) NUCLEAR EXCLUSION IN PERIPHERAL NEUROPATHIC PAIN IN MICE. THE RATIONALE OF SPINAL ADMINISTRATION OF ENDOTHELIN-1(ET-1) MEDIATED ANTI-NOCICEPTIVE EFFECT HAS NOT BEEN ELUCIDATED. ET-1 IS REPORTED TO PROMOTE NUCLEAR EFFLUXION OF HISTONE DEACETYLASE 5 (HDAC5) IN MYOCYTES, AND SPINAL HDAC5 IS IMPLICATED IN MODULATION OF PAIN PROCESSING. IN THIS STUDY, WE AIMED TO INVESTIGATE WHETHER CENTRAL ET-1 PLAYS AN ANTI-NOCICEPTIVE ROLE BY FACILITATING SPINAL HDAC5 NUCLEAR SHUTTLING UNDER NEUROPATHIC PAIN. HERE, WE DEMONSTRATE THAT UPREGULATING SPINAL ET-1 ATTENUATED THE NOCICEPTION INDUCED BY PARTIAL SCIATIC NERVE LIGATION SURGERY AND THIS ANALGESIC EFFECT MEDIATED BY ET-1 WAS ATTENUATED BY INTRATHECAL INJECTION OF ENDOTHELIN A RECEPTOR SELECTIVE INHIBITOR (BQ123) OR BY BLOCKING THE EXPORTATION OF NUCLEAR HDAC5 BY ADENO-ASSOCIATED VIRUSES TARGETING NEURONAL HDAC5 (AVV-HDAC5 S259/498A MUTANT). NOTABLY, ET-1 ADMINISTRATION INCREASED SPINAL GLUTAMATE ACID DECARBOXYLASES (GAD65/67) EXPRESSION VIA INITIATING HDAC5 NUCLEAR EXPORTATION AND INCREASED THE ACETYLATION OF HISTONE 3 AT LYSINE 9 (ACETYL-H3K9) IN THE PROMOTOR REGIONS OF SPINAL GAD1 AND GAD2 GENES. THIS WAS REVERSED BY BLOCKING ENDOTHELIN A RECEPTOR FUNCTION OR BY INHIBITING THE SPINAL NEURONAL NUCLEAR EXPORTATION OF HDAC5. THEREFORE, INDUCING SPINAL GABAERGIC NEURONAL HDAC5 NUCLEAR EXPORTATION MAY BE A NOVEL THERAPEUTIC APPROACH FOR MANAGING NEUROPATHIC PAIN. PERSPECTIVE: NEUROPATHIC PAIN IS INTRACTABLE IN A CLINICAL SETTING, AND EPIGENETIC REGULATION IS CONSIDERED TO CONTRIBUTE TO THIS PROCESSING. CHARACTERIZING THE ANTI-NOCICEPTIVE EFFECT OF ET-1 AND INVESTIGATING THE ASSOCIATED EPIGENETIC MECHANISMS IN ANIMAL MODELS MAY LEAD TO THE DEVELOPMENT OF NEW THERAPEUTIC STRATEGIES AND TARGETS FOR TREATING NEUROPATHIC PAIN.	2021	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            
10 4499  24 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	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
11 3194  27 HDAC INHIBITORS ATTENUATE THE DEVELOPMENT OF HYPERSENSITIVITY IN MODELS OF NEUROPATHIC PAIN. HISTONE DEACETYLASE INHIBITORS (HDACIS) INTERFERE WITH THE EPIGENETIC PROCESS OF HISTONE ACETYLATION AND ARE KNOWN TO HAVE ANALGESIC PROPERTIES IN MODELS OF CHRONIC INFLAMMATORY PAIN. THE AIM OF THIS STUDY WAS TO DETERMINE WHETHER THESE COMPOUNDS COULD ALSO AFFECT NEUROPATHIC PAIN. DIFFERENT CLASS I HDACIS WERE DELIVERED INTRATHECALLY INTO RAT SPINAL CORD IN MODELS OF TRAUMATIC NERVE INJURY AND ANTIRETROVIRAL DRUG-INDUCED PERIPHERAL NEUROPATHY (STAVUDINE, D4T). MECHANICAL AND THERMAL HYPERSENSITIVITY WAS ATTENUATED BY 40% TO 50% AS A RESULT OF HDACI TREATMENT, BUT ONLY IF STARTED BEFORE ANY INSULT. THE DRUGS GLOBALLY INCREASED HISTONE ACETYLATION IN THE SPINAL CORD, BUT APPEARED TO HAVE NO MEASURABLE EFFECTS IN RELEVANT DORSAL ROOT GANGLIA IN THIS TREATMENT PARADIGM, SUGGESTING THAT ANY POTENTIAL MECHANISM SHOULD BE SOUGHT IN THE CENTRAL NERVOUS SYSTEM. MICROARRAY ANALYSIS OF DORSAL CORD RNA REVEALED THE SIGNATURE OF THE SPECIFIC COMPOUND USED (MS-275) AND SUGGESTED THAT ITS MAIN EFFECT WAS MEDIATED THROUGH HDAC1. TAKEN TOGETHER, THESE DATA SUPPORT A ROLE FOR HISTONE ACETYLATION IN THE EMERGENCE OF NEUROPATHIC PAIN.	2013	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
12 5954  33 TBI-INDUCED NOCICEPTIVE SENSITIZATION IS REGULATED BY HISTONE ACETYLATION. CHRONIC PAIN AFTER TRAUMATIC BRAIN INJURY (TBI) IS VERY COMMON, BUT THE MECHANISMS LINKING TBI TO PAIN AND THE PAIN-RELATED INTERACTIONS OF TBI WITH PERIPHERAL INJURIES ARE POORLY UNDERSTOOD. IN THESE STUDIES WE PURSUED THE HYPOTHESIS THAT TBI PAIN SENSITIZATION IS ASSOCIATED WITH HISTONE ACETYLATION IN THE RAT LATERAL FLUID PERCUSSION MODEL. SOME ANIMALS RECEIVED HINDPAW INCISIONS IN ADDITION TO TBI TO MIMIC POLYTRAUMA. NEUROPATHOLOGICAL ANALYSIS OF BRAIN TISSUE FROM SHAM AND TBI ANIMALS REVEALED EVIDENCE OF BLEEDING, BREAKDOWN OF THE BLOOD BRAIN BARRIER, IN THE CORTEX, HIPPOCAMPUS, THALAMUS AND OTHER STRUCTURES RELATED TO PAIN SIGNAL PROCESSING. MECHANICAL ALLODYNIA WAS MEASURED IN THESE ANIMALS FOR UP TO EIGHT WEEKS POST-INJURY. INHIBITORS OF HISTONE ACETYLTRANSFERASE (HAT) AND HISTONE DEACETYLASE (HDAC) WERE USED TO PROBE THE ROLE OF HISTONE ACETYLATION IN SUCH PAIN PROCESSING. WE FOLLOWED SERUM MARKERS INCLUDING GLIAL FIBRILLARY ACIDIC PROTEIN (GFAP), NEURON-SPECIFIC ENOLASE 2 (NSE) MYELIN BASIC PROTEIN (MBP) AND S100BETA TO GAUGE TBI INJURY SEVERITY. OUR RESULTS SHOWED THAT TBI CAUSED MECHANICAL ALLODYNIA IN THE HINDPAWS OF THE RATS LASTING SEVERAL WEEKS. HINDPAWS CONTRALATERAL TO TBI SHOWED MORE RAPID AND PROFOUND SENSITIZATION THAN IPSILATERAL HINDPAWS. THE INHIBITION OF HAT USING CURCUMIN 50 MG/KG S.C REDUCED MECHANICAL SENSITIZATION WHILE THE HDAC INHIBITOR SUBEROYLANILIDE HYDROXAMIC ACID 50 MG/KG I.P. PROLONGED SENSITIZATION IN THE TBI RATS. IMMUNOHISTOCHEMICAL ANALYSES OF SPINAL CORD TISSUE LOCALIZED CHANGES IN THE LEVEL OF ACETYLATION OF THE H3K9 HISTONE MARK TO DORSAL HORN NEURONS. TAKEN TOGETHER, THESE FINDINGS DEMONSTRATE THAT TBI INDUCES SUSTAINED NOCICEPTIVE SENSITIZATION, AND CHANGES IN SPINAL NEURONAL HISTONE PROTEINS MAY PLAY AN IMPORTANT ROLE.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
13 6172  33 THE HDAC1/C-JUN COMPLEX IS ESSENTIAL IN THE PROMOTION OF NERVE INJURY-INDUCED NEUROPATHIC PAIN THROUGH JNK SIGNALING. HISTONE DEACETYLASE INHIBITORS (HDACIS) INTERFERE WITH THE EPIGENETIC PROCESS OF HISTONE ACETYLATION AND ARE KNOWN TO HAVE ANALGESIC PROPERTIES IN MODELS OF CHRONIC INFLAMMATORY PAIN. ADMINISTRATION OF A SELECTIVE HDAC1 INHIBITOR (LG325) IN SNI-SUBJECTED MICE SIGNIFICANTLY ATTENUATED BEHAVIOR RELATED TO INJURY-INDUCED PAIN. UNDERSTANDING THE HDAC1 PATHWAY IN EPIGENETIC REGULATION OF PATHOLOGICAL PAIN IS OF GREAT MEDICAL RELEVANCE. SPARED NERVE INJURY (SNI) MICE SHOWED A SIGNIFICANT INCREASE IN THE HDAC1 PROTEIN LEVELS WITHIN SPINAL CORD IN COINCIDENCE WITH THE NOCICEPTIVE PHENOTYPE AT 1 AND 3 WEEKS AFTER NERVE INJURY. NO VARIATION IN HDAC3, DNMT3A, ACH3, MBD3 AND MECP2 LEVELS WAS DETECTED. INCREASED EXPRESSION OF HDAC1 IS ACCOMPANIED BY ACTIVATION OF THE JNK-C-JUN SIGNALING PATHWAY. A ROBUST SPINAL JNK-1 OVERPHOSPHORYLATION WAS OBSERVED POST NERVE-INJURY ALONG WITH A SELECTIVE JNK-DEPENDENT INCREASE IN P-C-JUN AND HDAC1 PROTEIN LEVELS. CO-IMMUNOPRECIPITATION EXPERIMENTS SHOWED THE PRESENCE OF A HETERODIMERIC COMPLEX BETWEEN HDAC1 AND C-JUN IN SNI MICE INDICATING THAT THESE TRANSCRIPTION FACTORS CAN ACT TOGETHER TO REGULATE TRANSCRIPTION THROUGH HETERODIMERIZATION. STIMULATION OF C-JUN PHOSPHORYLATION WAS PREVENTED BY THE SELECTIVE HDAC1 INHIBITOR LG325. WE FOUND THAT HDAC1 WAS ASSOCIATED WITH C-JUN IN NUCLEI OF SPINAL DORSAL HORN ASTROCYTES EXPRESSING JNK. ON THE OTHER HAND, THE PRESENCE OF HDAC1 AND C-JUN INTERACTION WAS NOT DETECTED IN CONTROL MICE. THESE FINDINGS PROVIDE NEW INSIGHTS INTO THE MECHANISMS UNDERLYING THE ANTI-NOCICEPTIVE ACTIVITY OF HDAC INHIBITORS. TAKEN TOGETHER, THESE DATA SUPPORT A ROLE FOR HISTONE DEACETYLASE IN THE EMERGENCE OF NEUROPATHIC PAIN.	2018	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  
14 4851  36 OPIOIDS ENHANCE CXCL1 EXPRESSION AND FUNCTION AFTER INCISION IN MICE. CHRONIC OPIOID CONSUMPTION INCREASES POSTOPERATIVE PAIN. EPIGENETIC CHANGES RELATED TO CHRONIC OPIOID USE AND SURGICAL INCISION MAY BE PARTIALLY RESPONSIBLE FOR THIS ENHANCEMENT. THE CXCL1/CXCR2 SIGNALING PATHWAY, IMPLICATED IN SEVERAL PAIN MODELS, IS KNOWN TO BE EPIGENETICALLY REGULATED VIA HISTONE ACETYLATION. THE CURRENT STUDY WAS DESIGNED TO INVESTIGATE THE ROLE OF CXCL1/CXCR2 SIGNALING IN OPIOID-ENHANCED INCISIONAL SENSITIZATION AND TO ELUCIDATE THE POSSIBLE EPIGENETIC MECHANISM UNDERLYING CXCL1/CXCR2 PATHWAY-MEDIATED REGULATION OF NOCICEPTIVE SENSITIZATION IN MICE. CHRONIC MORPHINE TREATMENT GENERATED MECHANICAL AND THERMAL NOCICEPTIVE SENSITIZATION AND ALSO SIGNIFICANTLY EXACERBATED INCISION-INDUCED MECHANICAL ALLODYNIA. PERIPHERAL BUT NOT CENTRAL MESSENGER RNA LEVELS OF CXCL1 AND CXCR2 WERE INCREASED AFTER INCISION. THE SOURCE OF PERIPHERAL CXCL1 APPEARED TO BE WOUND AREA NEUTROPHILS. HISTONE H3 SUBUNIT ACETYLATED AT THE LYSINE 9 POSITION (ACH3K9) WAS INCREASED IN INFILTRATING DERMAL NEUTROPHILS AFTER INCISION AND WAS FURTHER INCREASED IN MICE WITH CHRONIC MORPHINE TREATMENT. THE ASSOCIATION OF ACH3K9 WITH THE PROMOTER REGION OF CXCL1 WAS ENHANCED IN MICE AFTER CHRONIC MORPHINE TREATMENT. THE INCREASE IN CXCL1 NEAR WOUNDS CAUSED BY CHRONIC MORPHINE PRETREATMENT WAS MIMICKED BY PHARMACOLOGIC INHIBITION OF HISTONE DEACETYLATION. FINALLY, LOCAL INJECTION OF CXCL1 INDUCED MECHANICAL SENSITIVITY IN NAIVE MICE, WHEREAS BLOCKING CXCR2 REVERSED MECHANICAL HYPERSENSITIVITY AFTER HIND PAW INCISION. PERSPECTIVE: PERIPHERAL CXCL1/CXCR2 SIGNALING HELPS TO CONTROL NOCICEPTIVE SENSITIZATION AFTER INCISION, AND EPIGENETIC REGULATION OF CXCL1 EXPRESSION EXPLAINS IN PART OPIOID-ENHANCED INCISIONAL ALLODYNIA IN MICE. THESE RESULTS SUGGEST THAT TARGETING CXCL1/CXCR2 SIGNALING MAY BE USEFUL IN TREATING NOCICEPTIVE SENSITIZATION, PARTICULARLY FOR POSTOPERATIVE PAIN IN CHRONIC OPIOID-CONSUMING PATIENTS.	2014	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
15 5708  29 SIRT1 ATTENUATES NEUROPATHIC PAIN BY EPIGENETIC REGULATION OF MGLUR1/5 EXPRESSIONS IN TYPE 2 DIABETIC RATS. ACCUMULATING EVIDENCE HAS DEMONSTRATED THAT EPIGENETIC MODIFICATION-MEDIATED CHANGES IN PAIN-RELATED GENE EXPRESSIONS PLAY AN IMPORTANT ROLE IN THE DEVELOPMENT AND MAINTENANCE OF NEUROPATHIC PAIN. SIRTUIN 1 (SIRT1), A NICOTINAMIDE ADENINE DINUCLEOTIDE (NAD)-DEPENDENT DEACETYLASE, IS INVOLVED IN THE DEVELOPMENT OF CHRONIC PAIN. MOREOVER, SIRT1 MAY BE A NOVEL THERAPEUTIC TARGET FOR THE PREVENTION OF TYPE 2 DIABETES MELLITUS (T2DM). BUT THE ROLE OF SIRT1 IN T2DM-INDUCED NEUROPATHIC PAIN REMAINS UNKNOWN. IN THIS STUDY, WE FOUND THAT SPINAL SIRT1 EXPRESSION AND ACTIVITY WERE DOWNREGULATED SIGNIFICANTLY IN HIGH-FAT-FED/LOW-DOSE STREPTOZOTOCIN-INDUCED NEUROPATHIC PAIN RATS. SIRT1 LOCALIZED IN SPINAL NEURONS BUT NOT IN ASTROCYTES OR MICROGLIA. FURTHERMORE, THE EXPRESSIONS OF METABOTROPIC GLUTAMATE RECEPTOR (MGLUR1) AND MGLUR5, WHICH PLAY A KEY ROLE IN CENTRAL SENSITIZATION AND NEUROPATHIC PAIN, AND H3 ACETYLATION LEVELS AT GRM1/5 (ENCODING MGLUR1/5) PROMOTER REGIONS WERE INCREASED IN DIABETIC NEUROPATHIC PAIN RATS. SIRT1 ACTIVATOR SRT1720 REVERSED THERMAL HYPERALGESIA AND MECHANICAL ALLODYNIA AND SPINAL NEURONAL ACTIVATION IN DIABETIC NEUROPATHIC PAIN RATS. CONCURRENTLY, INCREASED EXPRESSIONS OF MGLUR1/5 AND H3 ACETYLATION LEVELS AT GRM1/5 PROMOTER REGIONS WERE REVERSED BY SIRT1 ACTIVATION. IN ADDITION, KNOCKDOWN OF SIRT1 BY AD-SIRT1-SHRNA INDUCED PAIN BEHAVIORS AND SPINAL NEURONAL ACTIVATION IN NORMAL RATS, WHICH WAS ACCOMPANIED BY THE INCREASED EXPRESSIONS OF MGLUR1/5 AND H3 ACETYLATION LEVELS AT GRM1/5 PROMOTER REGIONS. THEREFORE, WE CONCLUDED THAT SIRT1-MEDIATED EPIGENETIC REGULATION OF MGLUR1/5 EXPRESSIONS WAS INVOLVED IN THE DEVELOPMENT OF NEUROPATHIC PAIN IN TYPE 2 DIABETIC RATS.	2017	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
16 1706  26 DYNORPHIN/KOP AND NOCICEPTIN/NOP GENE EXPRESSION AND EPIGENETIC CHANGES BY COCAINE IN RAT STRIATUM AND NUCLEUS ACCUMBENS. COCAINE INDUCES NEUROCHEMICAL CHANGES OF ENDOGENOUS PRODYNORPHIN-KAPPA OPIOID RECEPTOR (PDYN-KOP) AND PRONOCICEPTIN/ORPHANINFQ-NOCICEPTIN RECEPTOR (PN/OFQ-NOP) SYSTEMS. BOTH SYSTEMS PLAY AN IMPORTANT ROLE IN REWARDING MECHANISMS AND ADDICTIVE STIMULUS PROCESSING BY MODULATING DRUG-INDUCED DOPAMINERGIC ACTIVATION IN THE MESOCORTICO-LIMBIC BRAIN AREAS. THEY ARE ALSO INVOLVED IN REGULATING STRESS MECHANISMS RELATED TO ADDICTION. THE AIM OF THIS STUDY WAS TO INVESTIGATE POSSIBLE CHANGES OF GENE EXPRESSION OF THE DYNORPHINERGIC AND NOCICEPTINERGIC SYSTEM COMPONENTS IN THE NUCLEUS ACCUMBENS (NA) AND IN MEDIAL AND LATERAL CAUDATE PUTAMEN (MCPU AND LCPU, RESPECTIVELY) OF RATS, FOLLOWING CHRONIC SUBCUTANEOUS INFUSION OF COCAINE. IN ADDITION, THE EPIGENETIC HISTONE MODIFICATIONS H3K4ME3 AND H3K27ME3 (AN ACTIVATING AND A REPRESSIVE MARKER, RESPECTIVELY) AT THE PROMOTER LEVEL OF THE PDYN, KOP, PN/OFQ AND NOP GENES WERE INVESTIGATED. RESULTS SHOWED THAT COCAINE INDUCED PDYN GENE EXPRESSION UP-REGULATION IN THE NA AND LCPU, AND ITS DOWN-REGULATION IN THE MCPU, WHEREAS KOP MRNA LEVELS WERE UNCHANGED. MOREOVER, COCAINE EXPOSURE DECREASED PN/OFQ GENE EXPRESSION IN THE NA AND LCPU, WHILE NOP MRNA LEVELS APPEARED SIGNIFICANTLY INCREASED IN THE NA AND DECREASED IN THE LCPU. SPECIFIC CHANGES OF THE H3K4ME3 AND H3K27ME3 LEVELS WERE FOUND AT PDYN, PN/OFQ, AND NOP GENE PROMOTER, CONSISTENT WITH THE OBSERVED GENE EXPRESSION ALTERATIONS. THE PRESENT FINDINGS CONTRIBUTE TO BETTER DEFINE THE ROLE OF ENDOGENOUS PDYN-KOP AND PN/OFQ-NOP SYSTEMS IN NEUROPLASTICITY MECHANISMS FOLLOWING CHRONIC COCAINE TREATMENT. THE EPIGENETIC HISTONE MODIFICATIONS UNDERLYING THE GENE EXPRESSION CHANGES LIKELY MEDIATE THE EFFECTS OF COCAINE ON TRANSCRIPTIONAL REGULATION OF SPECIFIC GENE PROMOTERS THAT RESULT IN LONG-LASTING DRUG-INDUCED PLASTICITY.	2014	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
17 6148  31 THE EXPRESSION OF TRANSCRIPTION FACTORS MECP2 AND CREB IS MODULATED IN INFLAMMATORY PELVIC PAIN. EARLY ACTIVATION OF TRANSCRIPTION FACTORS IS ONE OF THE EPIGENETIC MECHANISMS CONTRIBUTING TO THE INDUCTION AND MAINTENANCE OF CHRONIC PAIN STATES. PREVIOUS STUDIES IDENTIFIED THE CHANGES IN A NUMBER OF NOCICEPTION-RELATED GENES, SUCH AS CALCITONIN GENE-RELATED PEPTIDE (CGRP), SUBSTANCE P (SP), AND BRAIN-DERIVED NEUROTROPIC FACTOR (BDNF) IN THE PELVIC ORGANS AFTER TRANSIENT COLONIC INFLAMMATION. THE GENE AND PROTEIN EXPRESSION OF THESE NEUROPEPTIDES COULD BE MODULATED BY TRANSCRIPTION FACTORS METHYL-CPG-BINDING PROTEIN 2 (MECP2) AND CAMP RESPONSE ELEMENT-BINDING PROTEIN (CREB). IN THIS STUDY, WE AIMED TO EVALUATE TIME-DEPENDENT CHANGES IN THE EXPRESSION LEVELS OF MECP2 AND CREB IN THE LUMBOSACRAL (LS) SPINAL CORD AND SENSORY GANGLIA AFTER INFLAMMATION-INDUCED PELVIC PAIN IN RAT. ADULT SPRAGUE-DAWLEY RATS WERE TREATED WITH 2,4,6-TRINITROBENZENESULFONIC ACID (TNBS) TO INDUCE TRANSIENT COLONIC INFLAMMATION. LS (L6-S2) SPINAL CORD SEGMENTS AND RESPECTIVE DORSAL ROOT GANGLIAS (DRGS) WERE ISOLATED FROM CONTROL AND EXPERIMENTAL ANIMALS AT 1, 2, 6, 24 H AND 3 DAYS POST-TNBS TREATMENT. IMMUNOHISTOCHEMICAL (IHC) LABELING AND WESTERN BLOTTING EXPERIMENTS WERE PERFORMED TO ASSESS THE EXPRESSION OF MECP2, CREB AND THEIR PHOSPHORYLATED FORMS. TOTAL MECP2 EXPRESSION, BUT NOT PHOSPHORYLATED P-MECP2 (PS421MECP2) EXPRESSION WAS DETECTED IN THE CELLS OF THE SPINAL DORSAL HORN UNDER CONTROL CONDITIONS. COLONIC INFLAMMATION TRIGGERED A SIGNIFICANT DECREASE IN THE NUMBER OF MECP2-EXPRESSING NEURONS IN PARALLEL WITH ELEVATED NUMBERS OF PS421MECP2-EXPRESSING CELLS AT 2 H AND 6 H POST-TNBS. THE MAJORITY OF MECP2-POSITIVE CELLS (80 +/- 6%) CO-EXPRESSED CREB. TNBS TREATMENT CAUSED A TRANSIENT UP-REGULATION OF CREB-EXPRESSING CELLS AT 1 H POST-TNBS ONLY. THE NUMBER OF CELLS EXPRESSING PHOSPHORYLATED CREB (PS133CREB) DID NOT CHANGE AT 1 H AND 2 H POST-TNBS, BUT WAS DOWN-REGULATED BY THREE FOLDS AT 6 H POST-TNBS. ANALYSIS OF DRG SECTIONS REVEALED THAT THE NUMBER OF MECP2-POSITIVE NEURONS WAS UP-REGULATED BY TNBS TREATMENT, REACHING THREE-FOLD INCREASE AT 2 H POST-TNBS, AND EIGHT-FOLD INCREASE AT 6 H POST-TNBS (P </= 0.05 TO CONTROL). THESE DATA SHOWED EARLY CHANGES IN MECP2 AND CREB EXPRESSION IN THE DORSAL HORN OF THE SPINAL CORD AND SENSORY GANGLIA AFTER COLONIC INFLAMMATION, SUGGESTING A POSSIBLE CONTRIBUTION MECP2 AND CREB SIGNALING IN THE DEVELOPMENT OF VISCERAL HYPERALGESIA AND PELVIC PAIN FOLLOWING PERIPHERAL INFLAMMATION.	2018	
                                                                                                                                                                                                                            
18  743  27 CANNABINOID TYPE 2 RECEPTOR SYSTEM MODULATES PACLITAXEL-INDUCED MICROGLIAL DYSREGULATION AND CENTRAL SENSITIZATION IN RATS. PACLITAXEL INDUCES MICROGLIAL ACTIVATION AND PRODUCTION OF PROINFLAMMATORY MEDIATORS IN THE DORSAL HORN, WHICH CONTRIBUTE TO THE DEVELOPMENT AND MAINTENANCE OF CENTRAL SENSITIZATION AND PAIN BEHAVIOR. MDA7, 1-([3-BENZYL-3-METHYL-2,3-DIHYDRO-1-BENZOFURAN-6-YL]CARBONYL) PIPERIDINE, IS A NOVEL HIGHLY SELECTIVE CANNABINOID TYPE 2 (CB2) AGONIST. WE TESTED THE HYPOTHESIS THAT ACTIVATION OF CB2 RECEPTOR BY MDA7 MODULATES MICROGLIAL DYSREGULATION, SUPPRESSES THE OVEREXPRESSION OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) IN MICROGLIA IN THE DORSAL HORN, AND ATTENUATES THE CENTRAL SENSITIZATION AND PAIN BEHAVIOR INDUCED BY PACLITAXEL. FOR 4 CONSECUTICE DAYS, GROUPS OF RATS RANDOMLY RECEIVED SALINE OR 1.0 MG/KG OF PACLITAXEL DAILY INTRAPERITONEALLY FOR A TOTAL CUMULATIVE DOSE OF 4 MG/KG. MDA7 15 MG/KG INTRAPERITONEALLY OR VEHICLE WERE ADMINISTERED 15 MIN BEFORE ADMINISTERING PACLITAXEL FOR 4 DAYS AND THEN CONTINUED FOR ANOTHER 10 DAYS. BEHAVIORAL AND MOLECULAR STUDIES WERE PERFORMED. PACLITAXEL INDUCED THE EXPRESSION OF CB2 RECEPTORS AND PRODUCTION OF INTERLEUKIN (IL)-6 IN MICROGLIA IN THE DORSAL HORN. MDA7 ATTENUATED THE EXPRESSION OF IL-6 AND PROMOTED THE EXPRESSION OF IL-10. PACLITAXEL INDUCED EPIGENETIC UPREGULATION OF IRF8 AND P2X PURINOCEPTOR 4 (P2X4) IN MICROGLIA AND SUBSEQUENTLY INCREASED THE EXPRESSION OF ALPHA ISOFORM OF CALCIUM/CALMODULIN-DEPENDENT PROTEIN KINASE II (CAMKIIALPHA), TRANSCRIPTIONAL FACTORS P-CREB AND DELTAFOSB, LEADING TO THE OVERPRODUCTION OF BDNF IN MICROGLIA. PACLITAXEL ALSO UPREGULATED THE EXPRESSION OF GLUTAMATE RECEPTOR SUBUNITS GLUR1 AND NR2B, DECREASED THE EXPRESSION OF K(+)-CL(-) COTRANSPORTER, AND INDUCED MECHANICAL ALLODYNIA IN RATS. ALL OF THE AFOREMENTIONED MOLECULAR CHANGES WERE ATTENUATED BY MDA7. OUR DATA SHOW THAT MDA7 ATTENUATED PACLITAXEL-INDUCED MOLECULAR AND BEHAVIORAL CHANGES IN RATS. PERSPECTIVE: THIS STUDY PROVIDES EVIDENCE THAT PACLITAXEL INDUCED MICROGLIA DYSREGULATION AND EPIGENETICALLY UPREGULATED THE MICROGLIAL EXPRESSION OF BDNF, WHICH LED TO SENSITIZATION OF DORSAL HORN NEURONS AND MECHANICAL ALLODYNIA IN RATS. THE CB2 AGONIST MDA7 ALLEVIATED THESE PATHOLOGICAL PROCESSES. MDA7 REPRESENTS AN INNOVATIVE THERAPEUTIC APPROACH FOR TREATMENT OF CHEMOTHERAPY-INDUCED NEUROPATHY.	2019	
                                                                                                                                                                                                                                                                                                                                                                                             
19 5781  29 SPINAL SIRT1 ACTIVATION ATTENUATES NEUROPATHIC PAIN IN MICE. ABNORMAL HISTONE ACETYLATION OCCURS DURING NEUROPATHIC PAIN THROUGH AN EPIGENETIC MECHANISM. SILENT INFORMATION REGULATOR 1 (SIR2 OR SIRT1), A NAD-DEPENDENT DEACETYLASE, PLAYS COMPLEX SYSTEMIC ROLES IN A VARIETY OF PROCESSES THROUGH DEACETYLATING ACETYLATED HISTONE AND OTHER SPECIFIC SUBSTRATES. BUT THE ROLE OF SIRT1 IN NEUROPATHIC PAIN IS NOT WELL ESTABLISHED YET. THE PRESENT STUDY WAS INTENDED TO DETECT SIRT1 CONTENT AND ACTIVITY, NICOTINAMIDE (NAM) AND NICOTINAMIDE ADENINE DINUCLEOTIDE (NAD) IN THE SPINAL CORD USING IMMUNOBLOTTING OR MASS SPECTROSCOPY OVER TIME IN MICE FOLLOWING CHRONIC CONSTRICTION INJURY (CCI) OR SHAM SURGERY. IN ADDITION, THE EFFECT OF INTRATHECAL INJECTION OF NAD OR RESVERATROL ON THERMAL HYPERALGESIA AND MECHANICAL ALLODYNIA WAS EVALUATED IN CCI MICE. FINALLY, WE INVESTIGATED WHETHER SIRT1 INHIBITOR EX-527 COULD REVERSE THE ANTI-NOCICEPTIVE EFFECT OF NAD OR RESVERATROL. IT WAS FOUND THAT SPINAL SIRT1 EXPRESSION, DEACETYLASE ACTIVITY AND NAD/NAM DECREASED SIGNIFICANTLY 1, 3, 7, 14 AND 21 DAYS AFTER CCI SURGERY AS COMPARED WITH SHAM GROUP. IN ADDITION, DAILY INTRATHECAL INJECTION OF 5 MICROL 800 MM NAD 1 H BEFORE AND 1 DAY AFTER CCI SURGERY OR SINGLE INTRATHECAL INJECTION OF 5 MICROL 90 MM RESVERATROL 1 H BEFORE CCI SURGERY PRODUCED A TRANSIENT INHIBITORY EFFECT ON THERMAL HYPERALGESIA AND MECHANICAL ALLODYNIA IN CCI MICE. FINALLY, AN INTRATHECAL INJECTION OF 5 MICROL 1.2 MM EX-527 1 H BEFORE NAD OR RESVERATROL ADMINISTRATION REVERSED THE ANTI-NOCICEPTIVE EFFECT OF NAD OR RESVERATROL. THESE DATA INDICATE THAT THE REDUCTION IN SIRT1 DEACETYLASE ACTIVITY MAY BE A FACTOR CONTRIBUTING TO THE DEVELOPMENT OF NEUROPATHIC PAIN IN CCI MICE. OUR FINDINGS SUGGEST THAT THE ENHANCEMENT OF SPINAL NAD/NAM AND/OR SIRT1 ACTIVITY MAY BE A POTENTIALLY PROMISING STRATEGY FOR THE PREVENTION OR TREATMENT OF NEUROPATHIC PAIN.	2014	
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
20 3141  26 GLOBAL GENE EXPRESSION AND CHROMATIN ACCESSIBILITY OF THE PERIPHERAL NERVOUS SYSTEM IN ANIMAL MODELS OF PERSISTENT PAIN. BACKGROUND: EFFORTS TO UNDERSTAND GENETIC VARIABILITY INVOLVED IN AN INDIVIDUAL'S SUSCEPTIBILITY TO CHRONIC PAIN SUPPORT A ROLE FOR UPSTREAM REGULATION BY EPIGENETIC MECHANISMS. METHODS: TO EXAMINE THE TRANSCRIPTOMIC AND EPIGENETIC BASIS OF CHRONIC PAIN THAT RESIDES IN THE PERIPHERAL NERVOUS SYSTEM, WE USED RNA-SEQ AND ATAC-SEQ OF THE RAT DORSAL ROOT GANGLION (DRG) TO IDENTIFY NOVEL MOLECULAR PATHWAYS ASSOCIATED WITH PAIN HYPERSENSITIVITY IN TWO WELL-STUDIED PERSISTENT PAIN MODELS INDUCED BY CHRONIC CONSTRICTION INJURY (CCI) OF THE SCIATIC NERVE AND INTRA-PLANTAR INJECTION OF COMPLETE FREUND'S ADJUVANT (CFA) IN RATS. RESULTS: OUR RNA-SEQ STUDIES IDENTIFY A VARIETY OF BIOLOGICAL PROCESS RELATED TO SYNAPSE ORGANIZATION, MEMBRANE POTENTIAL, TRANSMEMBRANE TRANSPORT, AND ION BINDING. INTERESTINGLY, GENES THAT ENCODE TRANSCRIPTIONAL REGULATORS WERE DISPROPORTIONATELY DOWNREGULATED IN BOTH MODELS. OUR ATAC-SEQ DATA PROVIDE A COMPREHENSIVE MAP OF CHROMATIN ACCESSIBILITY CHANGES IN THE DRG. A TOTAL OF 1123 REGIONS SHOWED CHANGES IN CHROMATIN ACCESSIBILITY IN ONE OR BOTH MODELS WHEN COMPARED TO THE NAIVE AND 31 SHARED DIFFERENTIALLY ACCESSIBLE REGIONS (DAR)S. FUNCTIONAL ANNOTATION OF THE DARS IDENTIFIED DISPARATE MOLECULAR FUNCTIONS ENRICHED FOR EACH PAIN MODEL WHICH SUGGESTS THAT CHROMATIN STRUCTURE MAY BE ALTERED DIFFERENTLY FOLLOWING SCIATIC NERVE INJURY AND HIND PAW INFLAMMATION. MOTIF ANALYSIS IDENTIFIED 17 DNA SEQUENCES KNOWN TO BIND TRANSCRIPTION FACTORS IN THE CCI DARS AND 33 IN THE CFA DARS. TWO MOTIFS WERE SIGNIFICANTLY ENRICHED IN BOTH MODELS. CONCLUSIONS: OUR IMPROVED UNDERSTANDING OF THE CHANGES IN CHROMATIN ACCESSIBILITY THAT OCCUR IN CHRONIC PAIN STATES MAY IDENTIFY REGULATORY GENOMIC ELEMENTS THAT PLAY ESSENTIAL ROLES IN MODULATING GENE EXPRESSION IN THE DRG.	2021