1 6697 167 VARICELLA-ZOSTER VIRUS HUMAN GANGLIONIC LATENCY: A CURRENT SUMMARY. VARICELLA-ZOSTER VIRUS (VZV) IS A UBIQUITOUS HUMAN HERPES VIRUS TYPICALLY ACQUIRED IN CHILDHOOD WHEN IT CAUSES VARICELLA (CHICKENPOX), FOLLOWING WHICH THE VIRUS ESTABLISHES A LATENT INFECTION IN TRIGEMINAL AND DORSAL ROOT GANGLIA THAT LASTS FOR THE LIFE OF THE INDIVIDUAL. VZV SUBSEQUENTLY REACTIVATES, SPONTANEOUSLY OR AFTER SPECIFIC TRIGGERING FACTORS, TO CAUSE HERPES ZOSTER (SHINGLES), WHICH MAY BE COMPLICATED BY POSTHERPETIC NEURALGIA AND SEVERAL OTHER NEUROLOGICAL COMPLICATIONS INCLUDING VASCULOPATHY. OUR UNDERSTANDING OF VZV LATENCY LAGS BEHIND OUR KNOWLEDGE OF HERPES SIMPLEX VIRUS TYPE 1 (HSV-1) LATENCY PRIMARILY DUE TO THE DIFFICULTY IN PROPAGATING THE VIRUS TO HIGH TITERS IN A CELL-FREE STATE, AND THE LACK OF A SUITABLE SMALL-ANIMAL MODEL FOR STUDYING VIRUS LATENCY AND REACTIVATION. IT IS NOW ESTABLISHED BEYOND DOUBT THAT LATENT VZV IS PREDOMINANTLY LOCATED IN HUMAN GANGLIONIC NEURONS. VIRUS GENE TRANSCRIPTION DURING LATENCY IS EPIGENETICALLY REGULATED, AND APPEARS TO BE RESTRICTED TO EXPRESSION OF AT LEAST SIX GENES, WITH EXPRESSION OF GENE 63 BEING THE HALLMARK OF LATENCY. HOWEVER, VIRAL GENE TRANSCRIPTION MAY BE MORE EXTENSIVE THAN PREVIOUSLY THOUGHT. THERE IS ALSO EVIDENCE FOR SEVERAL VZV GENES BEING EXPRESSED AT THE PROTEIN LEVEL, INCLUDING VZV GENE 63-ENCODED PROTEIN, BUT RECENT EVIDENCE SUGGESTS THAT THIS MAY NOT BE A COMMON EVENT. THE NATURE AND EXTENT OF THE CHRONIC INFLAMMATORY RESPONSE IN LATENTLY INFECTED GANGLIA IS ALSO OF CURRENT INTEREST. THERE REMAIN SEVERAL QUESTIONS CONCERNING THE VZV LATENCY PROCESS THAT STILL NEED TO BE RESOLVED UNAMBIGUOUSLY AND IT IS LIKELY THAT THIS WILL REQUIRE THE USE OF NEWLY DEVELOPED MOLECULAR TECHNOLOGIES, SUCH AS GEXPS MULTIPLEX POLYMERASE CHAIN REACTION (PCR) FOR VIRUS TRANSCRIPTIONAL ANALYSIS AND CHIP-SEQ TO STUDY THE EPIGENETIC OF LATENT VIRUS GENOME ( LIU ET AL, 2010 , BMC BIOL 8: 56). 2010 2 40 67 A COMPARISON OF HERPES SIMPLEX VIRUS TYPE 1 AND VARICELLA-ZOSTER VIRUS LATENCY AND REACTIVATION. HERPES SIMPLEX VIRUS TYPE 1 (HSV-1; HUMAN HERPESVIRUS 1) AND VARICELLA-ZOSTER VIRUS (VZV; HUMAN HERPESVIRUS 3) ARE HUMAN NEUROTROPIC ALPHAHERPESVIRUSES THAT CAUSE LIFELONG INFECTIONS IN GANGLIA. FOLLOWING PRIMARY INFECTION AND ESTABLISHMENT OF LATENCY, HSV-1 REACTIVATION TYPICALLY RESULTS IN HERPES LABIALIS (COLD SORES), BUT CAN OCCUR FREQUENTLY ELSEWHERE ON THE BODY AT THE SITE OF PRIMARY INFECTION (E.G. WHITLOW), PARTICULARLY AT THE GENITALS. RARELY, HSV-1 REACTIVATION CAN CAUSE ENCEPHALITIS; HOWEVER, A THIRD OF THE CASES OF HSV-1 ENCEPHALITIS ARE ASSOCIATED WITH HSV-1 PRIMARY INFECTION. PRIMARY VZV INFECTION CAUSES VARICELLA (CHICKENPOX) FOLLOWING WHICH LATENT VIRUS MAY REACTIVATE DECADES LATER TO PRODUCE HERPES ZOSTER (SHINGLES), AS WELL AS AN INCREASINGLY RECOGNIZED NUMBER OF SUBACUTE, ACUTE AND CHRONIC NEUROLOGICAL CONDITIONS. FOLLOWING PRIMARY INFECTION, BOTH VIRUSES ESTABLISH A LATENT INFECTION IN NEURONAL CELLS IN HUMAN PERIPHERAL GANGLIA. HOWEVER, THE DETAILED MECHANISMS OF VIRAL LATENCY AND REACTIVATION HAVE YET TO BE UNRAVELLED. IN BOTH CASES LATENT VIRAL DNA EXISTS IN AN 'END-LESS' STATE WHERE THE ENDS OF THE VIRUS GENOME ARE JOINED TO FORM STRUCTURES CONSISTENT WITH UNIT LENGTH EPISOMES AND CONCATEMERS, FROM WHICH VIRAL GENE TRANSCRIPTION IS RESTRICTED. IN LATENTLY INFECTED GANGLIA, THE MOST ABUNDANTLY DETECTED HSV-1 RNAS ARE THE SPLICED PRODUCTS ORIGINATING FROM THE PRIMARY LATENCY ASSOCIATED TRANSCRIPT (LAT). THIS PRIMARY LAT IS AN 8.3 KB UNSTABLE TRANSCRIPT FROM WHICH TWO STABLE (1.5 AND 2.0 KB) INTRONS ARE SPLICED. TRANSCRIPTS MAPPING TO 12 VZV GENES HAVE BEEN DETECTED IN HUMAN GANGLIA REMOVED AT AUTOPSY; HOWEVER, IT IS DIFFICULT TO ASCRIBE THESE AS TRANSCRIPTS PRESENT DURING LATENT INFECTION AS EARLY-STAGE VIRUS REACTIVATION MAY HAVE TRANSPIRED IN THE POST-MORTEM TIME PERIOD IN THE GANGLIA. NONETHELESS, LOW-LEVEL TRANSCRIPTION OF VZV ORF63 HAS BEEN REPEATEDLY DETECTED IN MULTIPLE GANGLIA REMOVED AS CLOSE TO DEATH AS POSSIBLE. THERE IS INCREASING EVIDENCE THAT HSV-1 AND VZV LATENCY IS EPIGENETICALLY REGULATED. IN VITRO MODELS THAT PERMIT PATHWAY ANALYSIS AND IDENTIFICATION OF BOTH EPIGENETIC MODULATIONS AND GLOBAL TRANSCRIPTIONAL MECHANISMS OF HSV-1 AND VZV LATENCY HOLD MUCH PROMISE FOR OUR FUTURE UNDERSTANDING IN THIS COMPLEX AREA. THIS REVIEW SUMMARIZES THE MOLECULAR BIOLOGY OF HSV-1 AND VZV LATENCY AND REACTIVATION, AND ALSO PRESENTS FUTURE DIRECTIONS FOR STUDY. 2015 3 4645 27 NEUROPATHIC PAIN: FROM MECHANISMS TO TREATMENT. NEUROPATHIC PAIN CAUSED BY A LESION OR DISEASE OF THE SOMATOSENSORY NERVOUS SYSTEM IS A COMMON CHRONIC PAIN CONDITION WITH MAJOR IMPACT ON QUALITY OF LIFE. EXAMPLES INCLUDE TRIGEMINAL NEURALGIA, PAINFUL POLYNEUROPATHY, POSTHERPETIC NEURALGIA, AND CENTRAL POSTSTROKE PAIN. MOST PATIENTS COMPLAIN OF AN ONGOING OR INTERMITTENT SPONTANEOUS PAIN OF, FOR EXAMPLE, BURNING, PRICKING, SQUEEZING QUALITY, WHICH MAY BE ACCOMPANIED BY EVOKED PAIN, PARTICULAR TO LIGHT TOUCH AND COLD. ECTOPIC ACTIVITY IN, FOR EXAMPLE, NERVE-END NEUROMA, COMPRESSED NERVES OR NERVE ROOTS, DORSAL ROOT GANGLIA, AND THE THALAMUS MAY IN DIFFERENT CONDITIONS UNDERLIE THE SPONTANEOUS PAIN. EVOKED PAIN MAY SPREAD TO NEIGHBORING AREAS, AND THE UNDERLYING PATHOPHYSIOLOGY INVOLVES PERIPHERAL AND CENTRAL SENSITIZATION. MALADAPTIVE STRUCTURAL CHANGES AND A NUMBER OF CELL-CELL INTERACTIONS AND MOLECULAR SIGNALING UNDERLIE THE SENSITIZATION OF NOCICEPTIVE PATHWAYS. THESE INCLUDE ALTERATION IN ION CHANNELS, ACTIVATION OF IMMUNE CELLS, GLIAL-DERIVED MEDIATORS, AND EPIGENETIC REGULATION. THE MAJOR CLASSES OF THERAPEUTICS INCLUDE DRUGS ACTING ON ALPHA(2)DELTA SUBUNITS OF CALCIUM CHANNELS, SODIUM CHANNELS, AND DESCENDING MODULATORY INHIBITORY PATHWAYS. 2021 4 3280 36 HERPES ZOSTER OPHTHALMICUS FOLLOWING ONABOTULINUMTOXINA ADMINISTRATION FOR CHRONIC MIGRAINE: A CASE REPORT AND LITERATURE REVIEW. BACKGROUND: THERE IS A GROWING BODY OF LITERATURE DOCUMENTING LOCAL HERPES ZOSTER OUTBREAK FOLLOWING PROCEDURES. THE MECHANISM UNDERLYING THESE OUTBREAKS REMAINS ELUSIVE. WE PRESENT A CASE OF ZOSTER FOLLOWING ONABOTULINUMTOXINA (BTX) FOR MIGRAINE AND A LITERATURE REVIEW. METHODS: CHART AND LITERATURE REVIEW. CASE: A 72-YEAR-OLD WOMAN WITH CHRONIC MIGRAINE RECEIVED BTX INJECTIONS FOR 3 YEARS WITHOUT INCIDENT. SHE HAD A HISTORY OF THORACIC ZOSTER WITH SUBSEQUENT POST-HERPETIC NEURALGIA. IN AUGUST 2013, 48 HOURS AFTER RECEIVING BTX INJECTIONS, SHE DEVELOPED A PAINFUL RASH IN THE RIGHT V1 DISTRIBUTION CONSISTENT WITH HERPES ZOSTER OPHTHALMICUS. ONE WEEK LATER THE RASH HAD RESOLVED WITHOUT TREATMENT. LITERATURE REVIEW: WE IDENTIFIED 65 (INCLUDING 2 FROM JUEL-JENSON) CASES OF ZOSTER REACTIVATION FOLLOWING MINOR PROCEDURES. THESE CASES TEND TO BE IN YOUNG PATIENTS WITHOUT SPECIFIC RISK FACTORS. OUTBREAKS CHARACTERISTICALLY OCCUR AT THE LEVEL OF EXPOSURE TO LOCAL TRAUMA. DISCUSSION: OUR REVIEW SUGGESTS THAT LOCAL TRAUMA, REGARDLESS OF THE NATURE OF STIMULI, MAY BE SUFFICIENT FOR ZOSTER REACTIVATION. WE HYPOTHESIZE THAT THE STRESSORS IN THESE REPORTED CASES EXERT A LOCAL EPIGENETIC INFLUENCE ON VIRAL TRANSCRIPTION, ALLOWING FOR VIRAL REACTIVATION. CONCLUSION: ZOSTER IS A POTENTIAL COMPLICATION OF BTX ADMINISTRATION FOR CHRONIC MIGRAINE IN ADULTS. PHYSICIAN AWARENESS CAN REDUCE THE SIGNIFICANT MORBIDITY ASSOCIATED WITH THIS DISEASE. 2015 5 4708 35 NO ASSOCIATION OF POLYMORPHISMS IN NAV1.7 OR NERVE GROWTH FACTOR RECEPTOR GENES WITH TRIGEMINAL NEURALGIA. OBJECTIVE: TRIGEMINAL NEURALGIA IS DEFINED AS A SUDDEN SEVERE SHOCK-LIKE PAIN WITHIN THE DISTRIBUTION OF THE TRIGEMINAL NERVE. PAIN IS A SUBJECTIVE EXPERIENCE THAT IS INFLUENCED BY GENDER, CULTURE, ENVIRONMENT, PSYCHOLOGICAL TRAITS, AND GENES. SODIUM CHANNELS AND NERVE GROWTH FACTOR PLAY IMPORTANT ROLES IN THE TRANSMISSION OF NOCICEPTIVE SIGNALS AND PAIN. THE AIM OF THIS STUDY WAS TO INVESTIGATE THE OCCURRENCE OF NAV1.7 SODIUM CHANNEL AND NERVE GROWTH FACTOR RECEPTOR TRKA GENE POLYMORPHISMS (SCN9A/RS6746030 AND NTRK1/RS633, RESPECTIVELY) IN TRIGEMINAL NEURALGIA PATIENTS. METHODS: NINETY-SIX SUBJECTS FROM PAIN SPECIALTY CENTERS IN THE SOUTHEASTERN REGION OF BRAZIL WERE DIVIDED INTO 2 GROUPS: 48 WITH CLASSICAL TRIGEMINAL NEURALGIA DIAGNOSIS AND 48 CONTROLS. PAIN WAS EVALUATED USING THE VISUAL ANALOG SCALE AND MULTIDIMENSIONAL MCGILL PAIN QUESTIONNAIRE. GENOMIC DNA WAS OBTAINED FROM ORAL SWABS IN ALL INDIVIDUALS AND WAS ANALYZED BY REAL-TIME POLYMERASE CHAIN REACTION. RESULTS: NO ASSOCIATION WAS OBSERVED BETWEEN EVALUATED POLYMORPHISMS AND TRIGEMINAL NEURALGIA. FOR ALLELE ANALYSES, PATIENTS AND CONTROLS HAD SIMILAR FREQUENCIES FOR BOTH GENES. GENOTYPE DISTRIBUTION OR ALLELE FREQUENCIES OF POLYMORPHISMS ANALYZED HERE DID NOT CORRELATE TO PAIN SCORES. CONCLUSIONS: ALTHOUGH NO ASSOCIATION OF EVALUATED POLYMORPHISMS AND TRIGEMINAL NEURALGIA DIAGNOSIS OR PAIN SEVERITY WAS OBSERVED, OUR DATA DO NOT EXCLUDE THE POSSIBILITY THAT OTHER GENOTYPES AFFECTING THE EXPRESSION OF NAV1.7 OR TRKA ARE ASSOCIATED WITH THE DISEASE. FURTHER STUDIES SHOULD INVESTIGATE DISTINCT GENETIC POLYMORPHISMS AND EPIGENETIC FACTORS THAT MAY BE IMPORTANT IN EXPRESSION OF THESE MOLECULES. 2019 6 1881 26 EMERGING TREATMENTS FOR NEUROPATHIC PAIN. NEUROPATHIC PAIN IS A SERIES OF WELL-KNOWN CONDITIONS CAUSED BY DISEASES OR LESIONS TO THE SOMATOSENSORY SYSTEM. DUE TO THE BETTER UNDERSTANDING OF THE PATHOPHYSIOLOGY OF NEUROPATHIC PAIN, PREVIOUSLY UNEXPLORED THERAPIES HAVE BEEN USED WITH ENCOURAGING RESULTS. AS SUCH, ACETYL-L-CARNITINE (ALC), ALPHA-LIPOIC-ACID (ALA), CANNABINOIDS, CLONIDINE, EMA401, BOTULINUM TOXIN TYPE A, AND NEW VOLTAGE-GATED SODIUM CHANNEL BLOCKERS, CAN BE CITED. FURTHERMORE, NEW MODALITIES IN NEUROMODULATION SUCH AS HIGH-FREQUENCY SPINAL CORD STIMULATION, BURST STIMULATION, DORSAL ROOT GANGLION STIMULATION, TRANSCRANIAL DIRECT CURRENT STIMULATION, AND MANY OTHERS HAVE BEEN SHOWING EXCITING RESULTS. BESIDES, CHANGING PARADIGMS MAY OCCUR WITH THE ADVENT OF OPTOGENETICS AND A BETTER UNDERSTANDING OF EPIGENETIC REGULATION. THIS ARTICLE REVIEWS THE PUBLISHED LITERATURE ON THE TREATMENT OF NP. DESPITE THE INTERESTING RESULTS, RANDOMIZED CONTROLLED TRIALS ARE DEMANDED FOR THE MAJORITY OF THE THERAPIES PREVIOUSLY MENTIONED. 2015 7 5600 25 ROLES OF VOLTAGE-DEPENDENT SODIUM CHANNELS IN NEURONAL DEVELOPMENT, PAIN, AND NEURODEGENERATION. BESIDES INITIATING AND PROPAGATING ACTION POTENTIALS IN ESTABLISHED NEURONAL CIRCUITS, VOLTAGE-DEPENDENT SODIUM CHANNELS SCULPT AND BOLSTER THE FUNCTIONAL NEURONAL NETWORK FROM EARLY IN EMBRYONIC DEVELOPMENT THROUGH ADULTHOOD (E.G., DIFFERENTIATION OF OLIGODENDROCYTE PRECURSOR CELLS INTO OLIGODENDROCYTES, MYELINATING AXON; COMPETITION BETWEEN NEIGHBORING EQUIPOTENTIAL NEURITES FOR DEVELOPMENT INTO A SINGLE AXON; ENHANCING AND OPPOSING FUNCTIONAL INTERACTIONS WITH ATTRACTIVE AND REPULSIVE MOLECULES FOR AXON PATHFINDING; EXTENDING AND RETRACTING TERMINAL ARBORIZATION OF AXON FOR CORRECT SYNAPSE FORMATION; EXPERIENCE-DRIVEN COGNITION; NEURONAL SURVIVAL; AND REMYELINATION OF DEMYELINATED AXONS). SURPRISINGLY, DIFFERENT PATTERNS OF ACTION POTENTIALS DIRECT HOMEOSTASIS-BASED EPIGENETIC SELECTION FOR NEUROTRANSMITTER PHENOTYPE, THUS EXCITABILITY BY SODIUM CHANNELS SPECIFYING EXPRESSION OF INHIBITORY NEUROTRANSMITTERS. MECHANISMS FOR THESE PLEIOTROPIC EFFECTS OF SODIUM CHANNELS INCLUDE RECIPROCAL INTERACTIONS BETWEEN NEURONS AND GLIA VIA NEUROTRANSMITTERS, GROWTH FACTORS, AND CYTOKINES AT SYNAPSES AND AXONS. SODIUM CHANNELOPATHIES CAUSING PAIN (E.G., ALLODYNIA) AND NEURODEGENERATION (E.G., MULTIPLE SCLEROSIS) DERIVE FROM 1) ELECTROPHYSIOLOGICAL DISTURBANCES BY INSULTS (E.G., ISCHEMIA/HYPOXIA, TOXINS, AND ANTIBODIES); 2) LOSS-OF-PHYSIOLOGICAL FUNCTION OR GAIN-OF-PATHOLOGICAL FUNCTION OF MUTANT SODIUM CHANNEL PROTEINS; 3) SPATIOTEMPORAL INAPPROPRIATE EXPRESSION OF NORMAL SODIUM CHANNEL PROTEINS; OR 4) DE-REPRESSED EXPRESSION OF OTHERWISE SILENT SODIUM CHANNEL GENES. NA(V)1.7 PROVED TO ACCOUNT FOR PAIN IN HUMAN ERYTHERMALGIA AND INFLAMMATION, BEING THE CONVINCING MOLECULAR TARGET OF PAIN TREATMENT. 2006 8 4644 23 NEUROPATHIC PAIN TREATMENT: STILL A CHALLENGE. NEUROPATHIC PAIN (NP) IS THE RESULT OF A SERIES OF CONDITIONS CAUSED BY DISEASES OR LESIONS TO THE SOMATOSENSORY SYSTEM. DUE TO THE BETTER UNDERSTANDING OF NP PATHOPHYSIOLOGY PREVIOUSLY UNEXPLORED THERAPIES HAVE BEEN USED WITH ENCOURAGING RESULTS. IN THIS GROUP, ACETYL-L-CARNITINE, ALPHA-LIPOIC-ACID, CANNABINOIDS, CLONIDINE, EMA401, BOTULINUM TOXIN TYPE A AND NEW VOLTAGE-GATED SODIUM CHANNEL BLOCKERS, CAN BE INCLUDED. BESIDES, CHANGING PARADIGMS MAY OCCUR WITH THE ADVENT OF OPTOGENETICS AND A BETTER UNDERSTANDING OF EPIGENETIC REGULATION. WE REVIEWED THE PUBLISHED LITERATURE ON THE PHARMACOLOGICAL TREATMENT OF NP. DESPITE THE INTERESTING RESULTS, RANDOMIZED CONTROLLED TRIALS ARE DEMANDED THE MAJORITY OF THE THERAPIES PREVIOUSLY MENTIONED. IN SPITE OF SEVERAL STUDIES FOR THE RELIEF OF NP, PAIN CONTROL CONTINUES BEING A CHALLENGE. 2016 9 803 34 CENTRAL CONTROL OF VISCERAL PAIN AND URINARY TRACT FUNCTION. AFFERENT INPUT FROM ADELTA AND C-FIBRES INNERVATING THE URINARY BLADDER ARE PROCESSED DIFFERENTLY BY THE BRAIN, AND HAVE DIFFERENT ROLES IN SIGNALING BLADDER SENSATION. ADELTA FIBRES THAT SIGNAL BLADDER FILLING ACTIVATE A SPINO-BULBO-SPINAL LOOP, WHICH RELAYS IN THE MIDBRAIN PERIAQUEDUCTAL GREY (PAG) AND PONTINE MICTURITION CENTRE (PMC). THE EXCITABILITY OF THIS CIRCUITRY IS REGULATED BY TONIC GABAERGIC INHIBITORY PROCESSES. IN HUMANS AND SOCIALISED ANIMALS MICTURITION IS NORMALLY UNDER VOLITIONAL CONTROL AND INFLUENCED BY A HOST OF PSYCHOSOCIAL FACTORS. HIGHER NERVOUS DECISION-MAKING IN A SOCIAL CONTEXT TO 'GO NOW' OR 'DO NOT GO' PROBABLY RESIDES IN FRONTAL CORTICAL AREAS, WHICH ACT AS A CENTRAL CONTROL SWITCH FOR MICTURITION. EXPOSURE TO PSYCHOSOCIAL STRESS CAN HAVE PROFOUNDLY DISRUPTIVE INFLUENCE ON THE PROCESS AND LEAD TO MALADAPTIVE CHANGES IN THE BLADDER. DURING SLEEPING THE VOIDING REFLEX THRESHOLD APPEARS TO BE RESET TO A HIGHER LEVEL TO PROMOTE URINARY CONTINENCE. UNDER PHYSIOLOGICAL CONDITIONS C-FIBRE BLADDER AFFERENTS ARE NORMALLY SILENT BUT ARE ACTIVATED IN INFLAMMATORY BLADDER STATES AND BY INTENSE DISTENDING PRESSURE. FOLLOWING PROLONGED STIMULATION VISCERAL NOCICEPTORS SENSITISE, LEADING TO A LOWERED THRESHOLD AND HEIGHTENED SENSITIVITY. IN ADDITION, SENSITIZATION MAY OCCUR WITHIN THE CENTRAL PAIN PROCESSING CIRCUITRY, WHICH OUTLASTS THE ORIGINAL NOCICEPTIVE INSULT. VISCERAL NOCICEPTION MAY ALSO BE INFLUENCED BY GENETIC AND ENVIRONMENTAL INFLUENCES. A PERIOD OF CHRONIC STRESS CAN PRODUCE INCREASED SENSITIVITY TO VISCERAL PAIN THAT LASTS FOR MONTHS. ADVERSE EARLY LIFE EVENTS CAN PRODUCE EVEN LONGER LASTING EPIGENETIC CHANGES, WHICH INCREASE THE INDIVIDUAL'S SUSCEPTIBILITY TO DEVELOPING VISCERAL PAIN STATES IN ADULTHOOD. 2016 10 2565 30 EPIGENETICS INVOLVEMENT IN OXALIPLATIN-INDUCED POTASSIUM CHANNEL TRANSCRIPTIONAL DOWNREGULATION AND HYPERSENSITIVITY. PERIPHERAL NEUROPATHY IS THE MOST FREQUENT DOSE-LIMITING ADVERSE EFFECT OF OXALIPLATIN. ACUTE PAIN SYMPTOMS THAT ARE INDUCED OR EXACERBATED BY COLD OCCUR IN ALMOST ALL PATIENTS IMMEDIATELY FOLLOWING THE FIRST INFUSIONS. EVIDENCE HAS SHOWN THAT OXALIPLATIN CAUSES ION CHANNEL EXPRESSION MODULATIONS IN DORSAL ROOT GANGLIA NEURONS, WHICH ARE THOUGHT TO CONTRIBUTE TO PERIPHERAL HYPERSENSITIVITY. MOST DYSREGULATED GENES ENCODE ION CHANNELS INVOLVED IN COLD AND MECHANICAL PERCEPTION, NOTEWORTHY MEMBERS OF A SUB-GROUP OF POTASSIUM CHANNELS OF THE K2P FAMILY, TREK AND TRAAK. DOWNREGULATION OF THESE K2P CHANNELS HAS BEEN IDENTIFIED AS AN IMPORTANT TUNER OF ACUTE OXALIPLATIN-INDUCED HYPERSENSITIVITY. WE INVESTIGATED THE MOLECULAR MECHANISMS UNDERLYING THIS PERIPHERAL DYSREGULATION IN A MURINE MODEL OF NEUROPATHIC PAIN TRIGGERED BY A SINGLE OXALIPLATIN ADMINISTRATION. WE FOUND THAT OXALIPLATIN-MEDIATED TREK-TRAAK DOWNREGULATION, AS WELL AS DOWNREGULATION OF OTHER K(+) CHANNELS OF THE K2P AND KV FAMILIES, INVOLVES A TRANSCRIPTION FACTOR KNOWN AS THE NEURON-RESTRICTIVE SILENCER FACTOR (NRSF) AND ITS EPIGENETIC CO-REPRESSORS HISTONE DEACETYLASES (HDACS). NRSF KNOCKDOWN WAS ABLE TO PREVENT MOST OF THESE K(+) CHANNEL MRNA DOWNREGULATION IN MICE DORSAL ROOT GANGLION NEURONS AS WELL AS OXALIPLATIN-INDUCED ACUTE COLD AND MECHANICAL HYPERSENSITIVITY. INTERESTINGLY, PHARMACOLOGICAL INHIBITION OF CLASS I HDAC REPRODUCES THE ANTINOCICEPTIVE EFFECTS OF NRSF KNOCKDOWN AND LEADS TO AN INCREASED K(+) CHANNEL EXPRESSION IN OXALIPLATIN-TREATED MICE. 2021 11 3955 27 LONG MARCH TOWARD SAFE AND EFFECTIVE ANALGESIA BY ENHANCING GENE EXPRESSION OF KCC2: FIRST STEPS TAKEN. LOW INTRANEURONAL CHLORIDE IN SPINAL CORD DORSAL HORN PAIN RELAY NEURONS IS CRITICAL FOR PHYSIOLOGIC TRANSMISSION OF PRIMARY PAIN AFFERENTS BECAUSE LOW INTRANEURONAL CHLORIDE DICTATES WHETHER GABA-ERGIC AND GLYCIN-ERGIC NEUROTRANSMISSION IS INHIBITORY. IF THE NEURONAL CHLORIDE ELEVATES TO PATHOLOGIC LEVELS, THEN SPINAL CORD PRIMARY PAIN RELAY BECOMES LEAKY AND EXHIBITS THE BEHAVIORAL HALLMARKS OF PATHOLOGIC PAIN, NAMELY HYPERSENSITIVITY AND ALLODYNIA. LOW CHLORIDE IN SPINAL CORD DORSAL HORN NEURONS IS MAINTAINED BY PROPER GENE EXPRESSION OF KCC2 AND SUSTAINED PHYSIOLOGIC FUNCTION OF THE KCC2 CHLORIDE EXTRUDING ELECTRONEUTRAL TRANSPORTER. PERIPHERAL NERVE INJURY AND OTHER FORMS OF NEURAL INJURY EVOKE GREATLY DIMINISHED KCC2 GENE EXPRESSION AND SUBSEQUENT CORRUPTION OF INHIBITORY NEUROTRANSMISSION IN THE SPINAL CORD DORSAL HORN, THUS CAUSING DERAILMENT OF THE GATE FUNCTION FOR PAIN. HERE I REVIEW KEY DISCOVERIES THAT HAVE HELPED US UNDERSTAND THESE FUNDAMENTALS, AND FOCUS ON RECENT INSIGHTS RELATING TO THE DISCOVERY OF KCC2 GENE EXPRESSION ENHANCING COMPOUNDS VIA COMPOUND SCREENS IN NEURONS. ONE SUCH STUDY CHARACTERIZED THE KINASE INHIBITOR, KENPAULLONE, MORE IN-DEPTH, REVEALING ITS FUNCTION AS A ROBUST AND LONG-LASTING ANALGESIC IN PRECLINICAL MODELS OF NERVE INJURY AND CANCER BONE PAIN, ALSO ELUCIDATING ITS MECHANISM OF ACTION VIA GSK3BETA INHIBITION, DIMINISHING DELTA-CATENIN PHOSPHORYLATION, AND FACILITATING ITS NUCLEAR TRANSFER AND SUBSEQUENT ENHANCEMENT OF KCC2 GENE EXPRESSION BY DE-REPRESSING KAISO EPIGENETIC TRANSCRIPTIONAL REGULATOR. FUTURE DIRECTIONS RE KCC2 GENE EXPRESSION ENHANCEMENT ARE DISCUSSED, NAMELY COMBINATION WITH OTHER ANALGESICS AND ANALGESIC METHODS, SUCH AS SPINAL CORD STIMULATION AND ELECTROACUPUNCTURE, GENE THERAPY, AND LEVERAGING KCC2 GENE EXPRESSION-ENHANCING NANOMATERIALS. 2022 12 1390 14 DIAGNOSING NOCIPLASTIC PAIN IN CANCER SURVIVORS: A MAJOR STEP FORWARD. NOCIPLASTIC PAIN SYNDROMES INCLUDE PARTICULAR FIBROMYALGIA, IRRITABLE BOWEL SYNDROME, HEADACHE, COMPLEX REGIONAL PAIN SYNDROME, AND IDIOPATHIC OROFACIAL PAIN. SEVERAL MECHANISMS HAVE BEEN PROPOSED TO ACCOUNT FOR NOCIPLASTIC PAIN INCLUDING CENTRAL SENSITISATION, ALTERATIONS OF PAIN MODULATORY CONTROLS, EPIGENETIC CHANGES, AND PERIPHERAL MECHANISMS. IMPORTANTLY, NOCIPLASTIC PAIN MIGHT ALSO BE PRESENT IN PATIENTS WITH CANCER PAIN, PARTICULARLY THOSE WITH PAIN RELATED TO COMPLICATIONS OF CANCER TREATMENT. INCREASED AWARENESS OF NOCIPLASTIC PAIN ASSOCIATED WITH CANCER SHOULD HAVE IMPORTANT IMPLICATIONS FOR MONITORING AND MANAGING SUCH PATIENTS. 2023 13 4616 30 NERVE INJURY INCREASES BRAIN-DERIVED NEUROTROPHIC FACTOR LEVELS TO SUPPRESS BK CHANNEL ACTIVITY IN PRIMARY SENSORY NEURONS. ABNORMAL HYPEREXCITABILITY OF PRIMARY SENSORY NEURONS CONTRIBUTES TO NEUROPATHIC PAIN DEVELOPMENT AFTER NERVE INJURY. NERVE INJURY PROFOUNDLY REDUCES THE EXPRESSION OF BIG CONDUCTANCE CA(2+) -ACTIVATED K(+) (BK) CHANNELS IN THE DORSAL ROOT GANGLION (DRG). HOWEVER, LITTLE IS KNOWN ABOUT HOW NERVE INJURY AFFECTS BK CHANNEL ACTIVITY IN DRG NEURONS. IN THIS STUDY, WE DETERMINED THE CHANGES IN BK CHANNEL ACTIVITY IN DRG NEURONS IN A RAT MODEL OF NEUROPATHIC PAIN AND THE CONTRIBUTION OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) TO REDUCED BK CHANNEL ACTIVITY. THE BK CHANNEL ACTIVITY WAS PRESENT PREDOMINANTLY IN SMALL AND MEDIUM DRG NEURONS, AND LIGATION OF L5 AND L6 SPINAL NERVES PROFOUNDLY DECREASED THE BK CURRENT DENSITY IN THESE NEURONS. BLOCKING BK CHANNELS SIGNIFICANTLY INCREASED NEURONAL EXCITABILITY IN SHAM CONTROL, BUT NOT IN NERVE-INJURED, RATS. THE BDNF CONCENTRATION IN THE DRG WAS SIGNIFICANTLY GREATER IN NERVE-INJURED RATS THAN IN CONTROL RATS. BDNF TREATMENT LARGELY REDUCED BK CURRENTS IN DRG NEURONS IN CONTROL RATS, WHICH WAS BLOCKED BY EITHER ANTI-BDNF ANTIBODY OR K252A, A TRK RECEPTOR INHIBITOR. FURTHERMORE, EITHER ANTI-BDNF ANTIBODY OR K252A REVERSED REDUCTION IN BK CURRENTS IN INJURED DRG NEURONS. BDNF TREATMENT REDUCED THE MRNA LEVELS OF BKALPHA1 SUBUNIT IN DRG NEURONS, AND ANTI-BDNF ANTIBODY ATTENUATED THE REDUCTION IN THE BKALPHA1 MRNA LEVEL IN INJURED DRG NEURONS. THESE FINDINGS SUGGEST THAT NERVE INJURY PRIMARILY DIMINISHES THE BK CHANNEL ACTIVITY IN SMALL AND MEDIUM DRG NEURONS. INCREASED BDNF LEVELS CONTRIBUTE TO REDUCED BK CHANNEL ACTIVITY IN DRG NEURONS THROUGH EPIGENETIC AND TRANSCRIPTIONAL MECHANISMS IN NEUROPATHIC PAIN. 2012 14 3839 33 IPSC-DERIVED NEURAL PRECURSOR CELLS: POTENTIAL FOR CELL TRANSPLANTATION THERAPY IN SPINAL CORD INJURY. A NUMBER OF STUDIES HAVE DEMONSTRATED THAT TRANSPLANTATION OF NEURAL PRECURSOR CELLS (NPCS) PROMOTES FUNCTIONAL RECOVERY AFTER SPINAL CORD INJURY (SCI). HOWEVER, THE NPCS HAD BEEN MOSTLY HARVESTED FROM EMBRYONIC STEM CELLS OR FETAL TISSUE, RAISING THE ETHICAL CONCERN. YAMANAKA AND HIS COLLEAGUES ESTABLISHED INDUCED PLURIPOTENT STEM CELLS (IPSCS) WHICH COULD BE GENERATED FROM SOMATIC CELLS, AND THIS INNOVATIVE DEVELOPMENT HAS MADE RAPID PROGRESSION IN THE FIELD OF SCI REGENERATION. WE AND OTHER GROUPS SUCCEEDED IN PRODUCING NPCS FROM IPSCS, AND DEMONSTRATED BENEFICIAL EFFECTS AFTER TRANSPLANTATION FOR ANIMAL MODELS OF SCI. IN PARTICULAR, EFFICACY OF HUMAN IPSC-NPCS IN NON-HUMAN PRIMATE SCI MODELS FOSTERED MOMENTUM OF CLINICAL APPLICATION FOR SCI PATIENTS. AT THE SAME TIME, HOWEVER, ARTIFICIAL INDUCTION METHODS IN IPSC TECHNOLOGY CREATED ALTERNATIVE ISSUES INCLUDING GENETIC AND EPIGENETIC ABNORMALITIES, AND TUMORIGENICITY AFTER TRANSPLANTATION. TO OVERCOME THESE PROBLEMS, IT IS CRITICALLY IMPORTANT TO SELECT ORIGINS OF SOMATIC CELLS, USE INTEGRATION-FREE SYSTEM DURING TRANSFECTION OF REPROGRAMMING FACTORS, AND THOROUGHLY INVESTIGATE THE CHARACTERISTICS OF IPSC-NPCS WITH RESPECT TO QUALITY MANAGEMENT. MOREOVER, SINCE MOST OF THE PREVIOUS STUDIES HAVE FOCUSED ON SUBACUTE PHASE OF SCI, ESTABLISHMENT OF EFFECTIVE NPC TRANSPLANTATION SHOULD BE EVALUATED FOR CHRONIC PHASE HEREAFTER. OUR GROUP IS CURRENTLY PREPARING CLINICAL-GRADE HUMAN IPSC-NPCS, AND WILL MOVE FORWARD TOWARD CLINICAL STUDY FOR SUBACUTE SCI PATIENTS SOON IN THE NEAR FUTURE. 2018 15 6828 27 [GLOBAL UNDERSTANDING OF PAIN]. CLINICALLY, IT IS WELL-KNOWN THAT CHRONIC PAIN INDUCES DEPRESSION, ANXIETY, AND REDUCED QUALITY OF LIFE. NEUROPATHIC PAIN, WHICH IS CHARACTERIZED BY SPONTANEOUS BURNING PAIN, HYPERALGESIA AND ALLODYNIA, IS THE MOST DIFFICULT PAIN TO MANAGE IN THE PAIN CLINIC. HOWEVER, THE COMPLICATED PATHOPHYSIOLOGY OF NEUROPATHIC PAIN IS NOT YET UNDERSTOOD. A BETTER UNDERSTANDING OF ITS PATHOPHYSIOLOGY HAS GIVEN US MORE INSIGHT INTO ITS VARIOUS MECHANISMS AND POSSIBLE TREATMENT OPTIONS. THIS REVIEW WILL EXPLORE THE MOST CURRENT ISSUES IN THE FIELD OF PAIN, WITH A FOCUS ON TRANSCRIPTIONAL RESEARCH, EPIGENETIC RESEARCH AND POST-TRANSCRIPTIONAL RESEARCH. FOR A GLOBAL UNDERSTANDING OF THE PAIN, IT IS NECESSARY TO ANALYZE THE CORRELATION BETWEEN THESE TEMPORAL PARAMETERS AND PHENOMICS. 2012 16 3968 29 LONG-LASTING ANALGESIA VIA TARGETED IN SITU REPRESSION OF NA(V)1.7 IN MICE. CURRENT TREATMENTS FOR CHRONIC PAIN RELY LARGELY ON OPIOIDS DESPITE THEIR SUBSTANTIAL SIDE EFFECTS AND RISK OF ADDICTION. GENETIC STUDIES HAVE IDENTIFIED IN HUMANS KEY TARGETS PIVOTAL TO NOCICEPTIVE PROCESSING. IN PARTICULAR, A HEREDITARY LOSS-OF-FUNCTION MUTATION IN NA(V)1.7, A SODIUM CHANNEL PROTEIN ASSOCIATED WITH SIGNALING IN NOCICEPTIVE SENSORY AFFERENTS, LEADS TO INSENSITIVITY TO PAIN WITHOUT OTHER NEURODEVELOPMENTAL ALTERATIONS. HOWEVER, THE HIGH SEQUENCE AND STRUCTURAL SIMILARITY BETWEEN NA(V) SUBTYPES HAS FRUSTRATED EFFORTS TO DEVELOP SELECTIVE INHIBITORS. HERE, WE INVESTIGATED TARGETED EPIGENETIC REPRESSION OF NA(V)1.7 IN PRIMARY AFFERENTS VIA EPIGENOME ENGINEERING APPROACHES BASED ON CLUSTERED REGULARLY INTERSPACED SHORT PALINDROMIC REPEATS (CRISPR)-DCAS9 AND ZINC FINGER PROTEINS AT THE SPINAL LEVEL AS A POTENTIAL TREATMENT FOR CHRONIC PAIN. TOWARD THIS END, WE FIRST OPTIMIZED THE EFFICIENCY OF NA(V)1.7 REPRESSION IN VITRO IN NEURO2A CELLS AND THEN, BY THE LUMBAR INTRATHECAL ROUTE, DELIVERED BOTH EPIGENOME ENGINEERING PLATFORMS VIA ADENO-ASSOCIATED VIRUSES (AAVS) TO ASSESS THEIR EFFECTS IN THREE MOUSE MODELS OF PAIN: CARRAGEENAN-INDUCED INFLAMMATORY PAIN, PACLITAXEL-INDUCED NEUROPATHIC PAIN, AND BZATP-INDUCED PAIN. OUR RESULTS SHOW EFFECTIVE REPRESSION OF NA(V)1.7 IN LUMBAR DORSAL ROOT GANGLIA, REDUCED THERMAL HYPERALGESIA IN THE INFLAMMATORY STATE, DECREASED TACTILE ALLODYNIA IN THE NEUROPATHIC STATE, AND NO CHANGES IN NORMAL MOTOR FUNCTION IN MICE. WE ANTICIPATE THAT THIS LONG-LASTING ANALGESIA VIA TARGETED IN VIVO EPIGENETIC REPRESSION OF NA(V)1.7 METHODOLOGY WE DUB PAIN LATER, MIGHT HAVE THERAPEUTIC POTENTIAL IN MANAGEMENT OF PERSISTENT PAIN STATES. 2021 17 2066 21 EPIGENETIC CONTROL OF ION CHANNEL EXPRESSION AND CELL-SPECIFIC SPLICING IN NOCICEPTORS: CHRONIC PAIN MECHANISMS AND POTENTIAL THERAPEUTIC TARGETS. ION CHANNELS UNDERLIE ALL FORMS FOR ELECTRICAL SIGNALING INCLUDING THE TRANSMISSION OF INFORMATION ABOUT HARMFUL EVENTS. VOLTAGE-GATED CALCIUM ION CHANNELS HAVE DUAL FUNCTION, THEY SUPPORT ELECTRICAL SIGNALING AS WELL AS INTRACELLULAR CALCIUM SIGNALING THROUGH EXCITATION-DEPENDENT CALCIUM ENTRY ACROSS THE PLASMA MEMBRANE. MECHANISMS THAT REGULATE ION CHANNEL FORMS AND ACTIONS ARE ESSENTIAL FOR MYRIAD CELL FUNCTIONS AND THESE ARE TARGETED BY DRUGS AND THERAPEUTICS. WHEN DISRUPTED, THE CELLULAR MECHANISMS THAT CONTROL ION CHANNEL ACTIVITY CAN CONTRIBUTE TO DISEASE PATHOPHYSIOLOGY. FOR EXAMPLE, ALTERNATIVE PRE-MRNA SPLICING IS A MAJOR STEP IN DEFINING THE PRECISE COMPOSITION OF THE TRANSCRIPTOME ACROSS DIFFERENT CELL TYPES FROM EARLY CELLULAR DIFFERENTIATION TO PROGRAMMED APOPTOSIS. AN ESTIMATED 30% OF DISEASE-CAUSING MUTATIONS ARE ASSOCIATED WITH ALTERED ALTERNATIVE SPLICING, AND MIS-SPLICING IS A FEATURE OF NUMEROUS HIGHLY PREVALENT DISEASES INCLUDING NEURODEGENERATIVE, CANCER, AND CHRONIC PAIN. HERE WE DISCUSS THE IMPORTANT ROLE OF EPIGENETIC REGULATION OF GENE EXPRESSION AND CELL-SPECIFIC ALTERNATIVE SPLICING OF CALCIUM ION CHANNELS IN NOCICEPTORS, WITH EMPHASIS ON HOW THESE PROCESSES ARE DISRUPTED IN CHRONIC PAIN, THE POTENTIAL THERAPEUTIC BENEFIT OF CORRECTING OR COMPENSATING FOR ABERRANT ION CHANNEL SPLICING IN CHRONIC PAIN. 2021 18 2179 34 EPIGENETIC MECHANISMS OF NEURAL PLASTICITY IN CHRONIC NEUROPATHIC PAIN. NEUROPATHIC PAIN IS A CHALLENGING CLINICAL PROBLEM AND REMAINS DIFFICULT TO TREAT. ALTERED GENE EXPRESSION IN PERIPHERAL SENSORY NERVES AND NEURONS DUE TO NERVE INJURY IS WELL DOCUMENTED AND CONTRIBUTES CRITICALLY TO THE SYNAPTIC PLASTICITY IN THE SPINAL CORD AND THE INITIATION AND MAINTENANCE OF CHRONIC PAIN. HOWEVER, OUR UNDERSTANDING OF THE EPIGENETIC MECHANISMS REGULATING THE TRANSCRIPTION OF PRO-NOCICEPTIVE (E.G., NMDA RECEPTORS AND ALPHA2DELTA-1) AND ANTINOCICEPTIVE (E.G., POTASSIUM CHANNELS AND OPIOID AND CANNABINOID RECEPTORS) GENES ARE STILL LIMITED. IN THIS REVIEW, WE SUMMARIZE RECENT STUDIES DETERMINING THE ROLES OF HISTONE MODIFICATIONS (INCLUDING METHYLATION, ACETYLATION, AND UBIQUITINATION), DNA METHYLATION, AND NONCODING RNAS IN NEUROPATHIC PAIN DEVELOPMENT. WE REVIEW THE EPIGENETIC WRITER, READER, AND ERASER PROTEINS THAT PARTICIPATE IN THE TRANSCRIPTIONAL CONTROL OF THE EXPRESSION OF KEY ION CHANNELS AND NEUROTRANSMITTER RECEPTORS IN THE DORSAL ROOT GANGLION AFTER TRAUMATIC NERVE INJURY, WHICH IS COMMONLY USED AS A PRECLINICAL MODEL OF NEUROPATHIC PAIN. A BETTER UNDERSTANDING OF EPIGENETIC REPROGRAMMING INVOLVED IN THE TRANSITION FROM ACUTE TO CHRONIC PAIN COULD LEAD TO THE DEVELOPMENT OF NEW TREATMENTS FOR NEUROPATHIC PAIN. 2022 19 55 34 A GAIN-OF-FUNCTION SODIUM CHANNEL BETA2-SUBUNIT MUTATION IN PAINFUL DIABETIC NEUROPATHY. DIABETES MELLITUS IS A GLOBAL CHALLENGE WITH MANY DIVERSE HEALTH SEQUELAE, OF WHICH DIABETIC PERIPHERAL NEUROPATHY IS ONE OF THE MOST COMMON. A SUBSTANTIAL NUMBER OF PATIENTS WITH DIABETIC PERIPHERAL NEUROPATHY DEVELOP CHRONIC PAIN, BUT THE GENETIC AND EPIGENETIC FACTORS THAT PREDISPOSE DIABETIC PERIPHERAL NEUROPATHY PATIENTS TO DEVELOP NEUROPATHIC PAIN ARE POORLY UNDERSTOOD. RECENT TARGETED GENETIC STUDIES HAVE IDENTIFIED MUTATIONS IN ALPHA-SUBUNITS OF VOLTAGE-GATED SODIUM CHANNELS (NA(V)S) IN PATIENTS WITH PAINFUL DIABETIC PERIPHERAL NEUROPATHY. MUTATIONS IN PROTEINS THAT REGULATE TRAFFICKING OR FUNCTIONAL PROPERTIES OF NA(V)S COULD EXPAND THE SPECTRUM OF PATIENTS WITH NA(V)-RELATED PERIPHERAL NEUROPATHIES. THE AUXILIARY SODIUM CHANNEL BETA-SUBUNITS (BETA1-4) HAVE BEEN REPORTED TO INCREASE CURRENT DENSITY, ALTER INACTIVATION KINETICS, AND MODULATE SUBCELLULAR LOCALIZATION OF NA(V). MUTATIONS IN BETA-SUBUNITS HAVE BEEN ASSOCIATED WITH SEVERAL DISEASES, INCLUDING EPILEPSY, CANCER, AND DISEASES OF THE CARDIAC CONDUCTING SYSTEM. HOWEVER, MUTATIONS IN BETA-SUBUNITS HAVE NEVER BEEN SHOWN PREVIOUSLY TO CONTRIBUTE TO NEUROPATHIC PAIN. WE REPORT HERE A PATIENT WITH PAINFUL DIABETIC PERIPHERAL NEUROPATHY AND NEGATIVE GENETIC SCREENING FOR MUTATIONS IN SCN9A, SCN10A, AND SCN11A-GENES ENCODING SODIUM CHANNEL ALPHA-SUBUNIT THAT HAVE BEEN PREVIOUSLY LINKED TO THE DEVELOPMENT OF NEUROPATHIC PAIN. GENETIC ANALYSIS REVEALED AN ASPARTIC ACID TO ASPARAGINE MUTATION, D109N, IN THE BETA2-SUBUNIT. FUNCTIONAL ANALYSIS USING CURRENT-CLAMP REVEALED THAT THE BETA2-D109N RENDERED DORSAL ROOT GANGLION NEURONS HYPEREXCITABLE, ESPECIALLY IN RESPONSE TO REPETITIVE STIMULATION. UNDERLYING THE HYPEREXCITABILITY INDUCED BY THE BETA2-SUBUNIT MUTATION, AS EVIDENCED BY VOLTAGE-CLAMP ANALYSIS, WE FOUND A DEPOLARIZING SHIFT IN THE VOLTAGE DEPENDENCE OF NA(V)1.7 FAST INACTIVATION AND REDUCED USE-DEPENDENT INHIBITION OF THE NA(V)1.7 CHANNEL. 2019 20 821 31 CHARACTERIZATION OF ACETYLATION OF HISTONE H3 AT LYSINE 9 IN THE TRIGEMINAL GANGLION OF A RAT TRIGEMINAL NEURALGIA MODEL. TRIGEMINAL NEURALGIA (TN) IS A CHRONIC NEUROPATHIC PAIN DISORDER CHARACTERIZED BY SPONTANEOUS AND ELICITED PAROXYSMS OF ELECTRIC-SHOCK-LIKE OR STABBING PAIN IN A REGION OF THE FACE. THE EPIGENETIC REGULATION OF TN IS STILL OBSCURE. IN CURRENT STUDY, A RAT TN MODEL SUBJECT TO CARBAMAZEPINE (CBZ) TREATMENT WAS ESTABLISHED, AND TRANSCRIPTOME- AND GENOME-SCALE PROFILING OF H3K9AC AND HDAC3 WAS PERFORMED BY RNA-SEQ AND CHIP-SEQ. WE OBSERVED THAT H3K9AC LEVELS IN THE TRIGEMINAL GANGLION WERE LOWER IN THE TN RATS COMPARED WITH THOSE IN THE CONTROL, AND CBZ TREATMENT LED TO RECOVERY OF H3K9AC LEVELS. FURTHER, WE FOUND THAT HDAC3 WAS OVERACTIVATED, WHICH INTERFERED WITH H3K9 ACETYLATION DUE TO HIGHER PHOSPHORYLATION IN TN COMPARED WITH THAT IN THE CONTROL. FINALLY, THE PHOSPHOKINASE LEUCINE-RICH REPEAT KINASE 2 (LRRK2) WAS DEMONSTRATED TO CONTRIBUTE TO HDAC3 ACTIVITY VIA THE MAPK SIGNALING PATHWAY. TAKEN TOGETHER, WE IDENTIFIED A REGULATORY MECHANISM IN WHICH THE PHOSPHATE GROUPS TRANSFERRED FROM ACTIVATED ERK AND LRRK2 TO HDAC3 CAUSED GENOME-SCALE DEACETYLATION AT H3K9 AND RESULTED IN THE SILENCING OF A LARGE NUMBER OF GENES IN TN. THE KINASES OR IMPORTANT ENZYMES WITHIN THIS REGULATORY AXIS MAY REPRESENT IMPORTANT TARGETS FOR TN THERAPY AND PREVENTION. 2022