1 6728 114 VOLTAGE-GATED CALCIUM CHANNELS AND PARKINSON'S DISEASE. A COMPLEX INTERACTION OF ENVIRONMENTAL, GENETIC AND EPIGENETIC FACTORS COMBINE WITH AGEING TO CAUSE THE MOST PREVALENT OF MOVEMENT DISORDERS PARKINSON'S DISEASE. CURRENT PHARMACOLOGICAL TREATMENTS ONLY TACKLE THE SYMPTOMS AND DO NOT STOP PROGRESSION OF THE DISEASE OR REVERSE THE NEURODEGENERATIVE PROCESS. WHILE SOME INCIDENCES OF PARKINSON'S DISEASE ARISE THROUGH HERITABLE GENETIC DEFECTS, THE CAUSE OF THE MAJORITY OF CASES REMAINS UNKNOWN. LIKEWISE, WHY SOME NEURONAL POPULATIONS ARE MORE SUSCEPTIBLE TO NEURODEGENERATION THAN OTHERS IS NOT CLEAR, BUT AS THE MOLECULAR PATHWAYS RESPONSIBLE FOR THE PROCESS OF CELL DEATH ARE UNRAVELLED, IT IS INCREASINGLY APPARENT THAT DISRUPTED CELLULAR ENERGY METABOLISM PLAYS A CENTRAL ROLE. PRECISE CONTROL OF CELLULAR CALCIUM CONCENTRATIONS IS CRUCIAL FOR MAINTENANCE OF ENERGY HOMEOSTASIS. RECENTLY, DIFFERENTIAL CELLULAR EXPRESSION OF NEURONAL VOLTAGE-GATED CALCIUM CHANNEL (CA(V)) ISOFORMS HAS BEEN IMPLICATED IN THE SUSCEPTIBILITY OF VULNERABLE NEURONS TO NEURODEGENERATION IN PARKINSON'S DISEASE. CA(V) CHANNELS ARE ALSO INVOLVED IN THE SYNAPTIC PLASTICITY RESPONSE TO THE DENERVATION THAT OCCURS IN PARKINSON'S DISEASE AND FOLLOWING CHRONIC TREATMENT WITH ANTI-PARKINSONIAN DRUGS. THIS REVIEW WILL EXAMINE THE PUTATIVE ROLE NEURONAL CA(V) CHANNELS HAVE IN THE PATHOGENESIS AND TREATMENT OF PARKINSON'S DISEASE. 2012 2 4783 31 NUTRIGENOMICS IN PARKINSON'S DISEASE: DIVERSITY OF MODULATORY ACTIONS OF POLYPHENOLS ON EPIGENETIC EFFECTS INDUCED BY TOXINS. ALTHOUGH THE PATHOGENESIS OF PARKINSON'S DISEASE (PD) IS NOT COMPLETELY UNDERSTOOD, THERE IS A CONSENSUS THAT IT CAN BE CAUSED BY MULTIFACTORIAL MECHANISMS INVOLVING GENETIC SUSCEPTIBILITY, EPIGENETIC MODIFICATIONS INDUCED BY TOXINS AND MITOCHONDRIAL DYSFUNCTION. IN THE PAST 20 YEARS, GREAT EFFORTS HAVE BEEN MADE IN ORDER TO CLARIFY MOLECULAR MECHANISMS THAT ARE RISK FACTORS FOR THIS DISEASE, AS WELL AS TO IDENTIFY BIOACTIVE AGENTS FOR PREVENTION AND SLOWING DOWN OF ITS PROGRESSION. NUTRACEUTICAL PRODUCTS HAVE RECEIVED SUBSTANTIAL INTEREST DUE TO THEIR NUTRITIONAL, SAFE AND THERAPEUTIC EFFECTS ON SEVERAL CHRONIC DISEASES. THE AIM OF THIS REVIEW WAS TO GATHER THE MAIN EVIDENCE OF THE EPIGENETIC MECHANISMS INVOLVED IN THE NEUROPROTECTIVE EFFECTS OF PHENOLIC COMPOUNDS CURRENTLY UNDER INVESTIGATION FOR THE TREATMENT OF TOXIN-INDUCED PD. THESE STUDIES CONFIRM THAT THE NEUROPROTECTIVE ACTIONS OF POLYPHENOLS INVOLVE COMPLEX EPIGENETIC MODULATIONS, DEMONSTRATING THAT THE INTAKE OF THESE NATURAL COMPOUNDS CAN BE A PROMISING, LOW-COST, PHARMACOGENOMIC STRATEGY AGAINST THE DEVELOPMENT OF PD. 2023 3 5369 21 RECENT ADVANCES IN UNDERSTANDING NEUROPATHIC PAIN: GLIA, SEX DIFFERENCES, AND EPIGENETICS. NEUROPATHIC PAIN RESULTS FROM DISEASES OR TRAUMA AFFECTING THE NERVOUS SYSTEM. THIS PAIN CAN BE DEVASTATING AND IS POORLY CONTROLLED. THE PATHOPHYSIOLOGY IS COMPLEX, AND IT IS ESSENTIAL TO UNDERSTAND THE UNDERLYING MECHANISMS IN ORDER TO IDENTIFY THE RELEVANT TARGETS FOR THERAPEUTIC INTERVENTION. IN THIS ARTICLE, WE FOCUS ON THE RECENT RESEARCH INVESTIGATING NEURO-IMMUNE COMMUNICATION AND EPIGENETIC PROCESSES, WHICH GAIN PARTICULAR ATTENTION IN THE CONTEXT OF NEUROPATHIC PAIN. SPECIFICALLY, WE ANALYZE THE ROLE OF GLIAL CELLS, INCLUDING MICROGLIA, ASTROCYTES, AND OLIGODENDROCYTES, IN THE MODULATION OF THE CENTRAL NERVOUS SYSTEM INFLAMMATION TRIGGERED BY NEUROPATHY. CONSIDERING EPIGENETICS, WE ADDRESS DNA METHYLATION, HISTONE MODIFICATIONS, AND THE NON-CODING RNAS IN THE REGULATION OF ION CHANNELS, G-PROTEIN-COUPLED RECEPTORS, AND TRANSMITTERS FOLLOWING NEURONAL DAMAGE. THE GOAL WAS NOT ONLY TO HIGHLIGHT THE EMERGING CONCEPTS BUT ALSO TO DISCUSS CONTROVERSIES, METHODOLOGICAL COMPLICATIONS, AND INTRIGUING OPINIONS. 2016 4 2963 29 GENETIC AND EPIGENETIC MECHANISMS LINKING PAIN AND PSYCHIATRIC DISORDERS. THE NEUROPHYSIOLOGICAL LINK BETWEEN NEUROPATHIC PAIN AND DEPRESSION REMAINS UNKNOWN DESPITE EVIDENT HIGH COMORBIDITY OF THESE TWO DISORDERS. HOWEVER, THERE IS CONVINCING EVIDENCE THAT GENOTYPE PLAYS A ROLE IN BOTH PAIN AND DEPRESSION. USING VARIOUS TYPES OF GENETIC ANALYSIS - POPULATION GENETICS, CYTOGENETICS AND MOLECULAR TECHNOLOGIES - SPECIFIC GENES HAVE BEEN IMPLICATED IN MEDIATING ALMOST ALL ASPECTS OF NOCICEPTION AND MOOD DISORDERS. THE CURRENT REVIEW ATTEMPTS TO IDENTIFY SPECIFIC GENES AND EPIGENETIC MECHANISMS COMMON TO BOTH DISORDERS. IT IS CONCLUDED THAT EXTERNAL AND INTERNAL FACTORS (INFLAMMATION, STRESS, GENDER, ETC.) THAT CONTRIBUTE TO THE PATHOLOGIES MAY DO SO THROUGH EPIGENETIC MECHANISMS THAT MAY AFFECT EXPRESSION OF THESE PARTICULAR GENES. THE POSSIBLE INVOLVEMENT OF EPIGENETIC REGULATION IN PAIN AND PSYCHIATRIC DISORDERS SUGGESTS THAT TREATMENTS TARGETING EPIGENETIC MECHANISMS THAT MEDIATE ADVERSE LIFE EVENTS SHOULD BE CONSIDERED. 2015 5 4635 35 NEUROINFLAMMATORY MECHANISMS IN PARKINSON'S DISEASE: POTENTIAL ENVIRONMENTAL TRIGGERS, PATHWAYS, AND TARGETS FOR EARLY THERAPEUTIC INTERVENTION. MOST ACUTE AND CHRONIC NEURODEGENERATIVE CONDITIONS ARE ACCOMPANIED BY NEUROINFLAMMATION; YET THE EXACT NATURE OF THE INFLAMMATORY PROCESSES AND WHETHER THEY MODIFY DISEASE PROGRESSION IS NOT WELL UNDERSTOOD. IN THIS REVIEW, WE DISCUSS THE KEY EPIDEMIOLOGICAL, CLINICAL, AND EXPERIMENTAL EVIDENCE IMPLICATING INFLAMMATORY PROCESSES IN THE PROGRESSIVE DEGENERATION OF THE DOPAMINERGIC (DA) NIGROSTRIATAL PATHWAY AND THEIR POTENTIAL CONTRIBUTION TO THE PATHOPHYSIOLOGY OF PARKINSON'S DISEASE (PD). GIVEN THAT INTERPLAY BETWEEN GENETICS AND ENVIRONMENT ARE LIKELY TO CONTRIBUTE TO RISK FOR DEVELOPMENT OF IDIOPATHIC PD, RECENT DATA SHOWING INTERACTIONS BETWEEN PRODUCTS OF GENES LINKED TO HERITABLE PD THAT FUNCTION TO PROTECT DA NEURONS AGAINST OXIDATIVE OR PROTEOLYTIC STRESS AND INFLAMMATION PATHWAYS WILL BE DISCUSSED. CELLULAR MECHANISMS ACTIVATED OR ENHANCED BY INFLAMMATORY PROCESSES THAT MAY CONTRIBUTE TO MITOCHONDRIAL DYSFUNCTION, OXIDATIVE STRESS, OR APOPTOSIS OF DOPAMINERGIC (DA) NEURONS WILL BE REVIEWED, WITH SPECIAL EMPHASIS ON TUMOR NECROSIS FACTOR (TNF) AND INTERLEUKIN-1-BETA (IL-1BETA) SIGNALING PATHWAYS. EPIGENETIC FACTORS WHICH HAVE THE POTENTIAL TO TRIGGER NEUROINFLAMMATION, INCLUDING ENVIRONMENTAL EXPOSURES AND AGE-ASSOCIATED CHRONIC INFLAMMATORY CONDITIONS, WILL BE DISCUSSED AS POSSIBLE 'SECOND-HIT' TRIGGERS THAT MAY AFFECT DISEASE ONSET OR PROGRESSION OF IDIOPATHIC PD. IF INFLAMMATORY PROCESSES HAVE AN ACTIVE ROLE IN NIGROSTRIATAL PATHWAY DEGENERATION, THEN EVIDENCE SHOULD EXIST TO INDICATE THAT SUCH PROCESSES BEGIN IN THE EARLY STAGES OF DISEASE AND THAT THEY CONTRIBUTE TO NEURONAL DYSFUNCTION AND/OR HASTEN NEURODEGENERATION OF THE NIGROSTRIATAL PATHWAY. THERAPEUTICALLY, IF ANTI-INFLAMMATORY INTERVENTIONS CAN BE SHOWN TO RESCUE NIGRAL DA NEURONS FROM DEGENERATION AND LOWER PD RISK, THEN TIMELY USE OF ANTI-INFLAMMATORY THERAPIES SHOULD BE INVESTIGATED FURTHER IN WELL-DESIGNED CLINICAL TRIALS FOR THEIR ABILITY TO PREVENT OR DELAY THE PROGRESSIVE LOSS OF NIGRAL DA NEURONS IN GENETICALLY SUSCEPTIBLE POPULATIONS. 2007 6 6324 30 THE ROLE OF ALPHA-SYNUCLEIN IN THE PATHOPHYSIOLOGY OF ALCOHOLISM. ALCOHOLISM HAS COMPLEX ETIOLOGY AND THERE IS EVIDENCE FOR BOTH GENETIC AND ENVIRONMENTAL FACTORS IN ITS PATHOPHYSIOLOGY. CHRONIC, LONG-TERM ALCOHOL ABUSE AND ALCOHOL DEPENDENCE ARE ASSOCIATED WITH NEURONAL LOSS WITH THE PREFRONTAL CORTEX BEING PARTICULARLY SUSCEPTIBLE TO NEUROTOXIC DAMAGE. THIS BRAIN REGION IS INVOLVED IN THE DEVELOPMENT AND PERSISTENCE OF ALCOHOL ADDICTION AND NEUROTOXIC DAMAGE IS LIKELY TO EXACERBATE THE REINFORCING EFFECTS OF ALCOHOL AND MAY HINDER TREATMENT. UNDERSTANDING THE MECHANISM OF ALCOHOL'S NEUROTOXIC EFFECTS ON THE BRAIN AND THE GENETIC RISK FACTORS ASSOCIATED WITH ALCOHOL ABUSE ARE THE FOCUS OF CURRENT RESEARCH. BECAUSE OF ITS WELL-ESTABLISHED ROLE IN NEURODEGENERATIVE AND NEUROPSYCHOLOGICAL DISORDERS, AND ITS EMERGING ROLE IN THE PATHOPHYSIOLOGY OF ADDICTION, HERE WE REVIEW THE GENETIC AND EPIGENETIC FACTORS INVOLVED IN REGULATING ALPHA-SYNUCLEIN EXPRESSION AND ITS POTENTIAL ROLE IN THE PATHOPHYSIOLOGY OF CHRONIC ALCOHOL ABUSE. ELUCIDATION OF THE MECHANISMS OF ALPHA-SYNUCLEIN REGULATION MAY PROVE BENEFICIAL IN UNDERSTANDING THE ROLE OF THIS KEY SYNAPTIC PROTEIN IN DISEASE AND ITS POTENTIAL FOR THERAPEUTIC MODULATION IN THE TREATMENT OF SUBSTANCE USE DISORDERS AS WELL AS OTHER NEURODEGENERATIVE DISEASES. 2013 7 2350 36 EPIGENETIC REGULATION OF NEUROINFLAMMATION IN PARKINSON'S DISEASE. NEUROINFLAMMATION IS ONE OF THE MOST SIGNIFICANT FACTORS INVOLVED IN THE INITIATION AND PROGRESSION OF PARKINSON'S DISEASE. PD IS A NEURODEGENERATIVE DISORDER WITH A MOTOR DISABILITY LINKED WITH VARIOUS COMPLEX AND DIVERSIFIED RISK FACTORS. THESE FACTORS TRIGGER MYRIADS OF CELLULAR AND MOLECULAR PROCESSES, SUCH AS MISFOLDING DEFECTIVE PROTEINS, OXIDATIVE STRESS, MITOCHONDRIAL DYSFUNCTION, AND NEUROTOXIC SUBSTANCES THAT INDUCE SELECTIVE NEURODEGENERATION OF DOPAMINE NEURONS. THIS NEURONAL DAMAGE ACTIVATES THE NEURONAL IMMUNE SYSTEM, INCLUDING GLIAL CELLS AND INFLAMMATORY CYTOKINES, TO TRIGGER NEUROINFLAMMATION. THE TRANSITION OF ACUTE TO CHRONIC NEUROINFLAMMATION ENHANCES THE SUSCEPTIBILITY OF INFLAMMATION-INDUCED DOPAMINERGIC NEURON DAMAGE, FORMING A VICIOUS CYCLE AND PROMPTING AN INDIVIDUAL TO PD DEVELOPMENT. EPIGENETIC MECHANISMS RECENTLY HAVE BEEN AT THE FOREFRONT OF THE REGULATION OF NEUROINFLAMMATORY FACTORS IN PD, PROPOSING A NEW DAWN FOR BREAKING THIS VICIOUS CYCLE. THIS REVIEW EXAMINED THE CORE EPIGENETIC MECHANISMS INVOLVED IN THE ACTIVATION AND PHENOTYPIC TRANSFORMATION OF GLIAL CELLS MEDIATED NEUROINFLAMMATION IN PD. WE FOUND THAT EPIGENETIC MECHANISMS DO NOT WORK INDEPENDENTLY, DESPITE BEING COORDINATED WITH EACH OTHER TO ACTIVATE NEUROINFLAMMATORY PATHWAYS. IN THIS REGARD, WE ATTEMPTED TO FIND THE SYNERGIC CORRELATION AND CONTRIBUTION OF THESE EPIGENETIC MODIFICATIONS WITH VARIOUS NEUROINFLAMMATORY PATHWAYS TO BROADEN THE CANVAS OF UNDERLYING PATHOLOGICAL MECHANISMS INVOLVED IN PD DEVELOPMENT. MOREOVER, THIS STUDY HIGHLIGHTED THE DUAL CHARACTERISTICS (NEUROPROTECTIVE/NEUROTOXIC) OF THESE EPIGENETIC MARKS, WHICH MAY COUNTERACT PD PATHOGENESIS AND MAKE THEM POTENTIAL CANDIDATES FOR DEVISING FUTURE PD DIAGNOSIS AND TREATMENT. 2021 8 676 35 BRAIN AGING: A IANUS-FACED PLAYER BETWEEN HEALTH AND NEURODEGENERATION. NEURODEGENERATIVE DISEASES ARE INCURABLE DEBILITATING DISORDERS CHARACTERIZED BY STRUCTURAL AND FUNCTIONAL NEURONAL LOSS. APPROXIMATELY 30 MILLION PEOPLE ARE AFFECTED WORLDWIDE, AND THIS NUMBER IS PREDICTED TO REACH MORE THAN 150 MILLION BY 2050. NEURODEGENERATIVE DISORDERS INCLUDE ALZHEIMER'S, PARKINSON'S, AND PRION DISEASES AMONG OTHERS. THESE DISORDERS ARE CHARACTERIZED BY THE ACCUMULATION OF AGGREGATING PROTEINS FORMING AMYLOID, RESPONSIBLE FOR THE DISEASE-ASSOCIATED PATHOLOGICAL LESIONS. THE AGGREGATION OF AMYLOIDOGENIC PROTEINS CAN RESULT EITHER IN GAINING OF TOXIC FUNCTIONS, DERIVED FROM THE DAMAGE PROVOKED BY THESE DEPOSITS IN AFFECTED TISSUE, OR IN A LOSS OF FUNCTIONS, DUE TO THE SEQUESTRATION AND THE CONSEQUENT INABILITY OF THE AGGREGATING PROTEIN TO ENSURE ITS PHYSIOLOGICAL ROLE. WHILE IT IS WIDELY ACCEPTED THAT AGING REPRESENTS THE MAIN RISK FACTOR FOR NEURODEGENERATION, THERE IS STILL NO CLEAR CUT-OFF LINE BETWEEN THE TWO CONDITIONS. INDEED, MANY OF THE PATHWAYS THAT ARE COMMONLY ALTERED IN NEURODEGENERATION-MISFOLDED PROTEIN ACCUMULATION, CHRONIC INFLAMMATION, MITOCHONDRIAL DYSFUNCTION, IMPAIRED IRON HOMEOSTASIS, EPIGENETIC MODIFICATIONS-HAVE BEEN OFTEN CORRELATED ALSO WITH HEALTHY AGING. THIS OVERLAP COULD BE EXPLAINED BY THE FACT THAT THE CONTINUOUS ACCUMULATION OF CELLULAR DAMAGES, TOGETHER WITH A PROGRESSIVE DECLINE IN METABOLIC EFFICIENCY DURING AGING, MAKES THE NEURONS MORE VULNERABLE TO TOXIC INJURIES. WHEN A GIVEN THRESHOLD IS EXCEEDED, ALL THESE ALTERATIONS MIGHT GIVE RISE TO PATHOLOGICAL PHENOTYPES THAT ULTIMATELY LEAD TO NEURODEGENERATION. 2020 9 6701 26 VASCULAR FACTORS AND EPIGENETIC MODIFICATIONS IN THE PATHOGENESIS OF ALZHEIMER'S DISEASE. ALZHEIMER'S DISEASE (AD) IS A DEBILITATING ILLNESS WITH NO KNOWN CURE. NOWADAYS ACCUMULATING EVIDENCE SUGGESTED THAT THE VASCULAR ENDOTHELIUM AND CHRONIC HYPOPERFUSION MAY PLAY IMPORTANT ROLE IN PATHOBIOLOGY OF AD. THE VASCULAR ENDOTHELIUM WHICH REGULATES THE PASSAGE OF MACROMOLECULES AND CIRCULATING CELLS FROM BLOOD TO TISSUE, IS A MAJOR TARGET OF OXIDATIVE STRESS, PLAYING A CRITICAL ROLE IN THE PATHOPHYSIOLOGY OF VASCULAR DISEASES. SINCE THE VASCULAR ENDOTHELIUM, NEURONS AND GLIA ARE ALL ABLE TO SYNTHESIZE, STORE AND RELEASE REACTIVE OXYGEN SPECIES (ROS) AND VASCULAR ACTIVE SUBSTANCES IN RESPONSE TO CERTAIN STIMULI, THEIR CONTRIBUTION TO THE PATHOPHYSIOLOGY OF AD CAN BE VERY IMPORTANT. NEW EVIDENCE INDICATES THAT CONTINUOUS FORMATION OF FREE ROS INDUCES CELLULAR DAMAGE AND DECREASES ANTIOXIDANT DEFENSES. SPECIFICALLY, OXIDATIVE STRESS INCREASES VASCULAR ENDOTHELIAL PERMEABILITY AND PROMOTES LEUKOCYTE ADHESION. WE SUMMARIZE THE REPORTS THAT SPORADIC, LATE-ONSET OF AD RESULTS FROM VASCULAR ETIOLOGY. RECENTLY AN INVOLVEMENT OF EPIGENETIC ALTERATIONS IN THE ETIOLOGY OF AD IS ALSO INTENSIVELY INVESTIGATED. GAINING A MORE COMPLETE UNDERSTANDING OF THE ESSENTIAL COMPONENTS AND UNDERLYING MECHANISMS INVOLVED IN EPIGENETIC REGULATION COULD LEAD TO NOVEL TREATMENTS FOR A NUMBER OF NEUROLOGICAL AND PSYCHIATRIC CONDITIONS. 2012 10 6807 19 [EPIGENETICS AND PAIN]. CHRONIC PAIN AFFECTS APPROXIMATELY 20 % OF ADULTS WORLDWIDE AND IS OFTEN ASSOCIATED WITH A DECREASE IN THE QUALITY OF LIFE AND VARIOUS COMORBIDITIES. CONVENTIONAL ANALGESIC THERAPIES ARE FREQUENTLY INSUFFICIENT AND SOMETIMES LEAD TO SEVERE SIDE EFFECTS. THEREFORE, GREAT EFFORTS ARE STILL BEING MADE TO ELUCIDATE THE SIGNALLING PATHWAYS IN PAIN AND TO DEVELOP NEW, SAFE AND EFFECTIVE THERAPIES. EPIGENETIC MECHANISMS WHICH INTERFERE WITH THE REGULATION OF GENE EXPRESSION ARE INVOLVED IN THE PATHOGENESIS OF SEVERAL DISEASES AND ARE GAINING INCREASING IMPETUS IN MEDICAL RESEARCH. AS THEY ARE ALSO INVOLVED IN PAIN PROCESSING, A MODULATION OF THESE MECHANISMS MIGHT REPRESENT A NOVEL OPTION FOR THE THERAPY OF PAIN PATIENTS. 2014 11 6347 28 THE ROLE OF EPIGENETICS IN NEUROINFLAMMATORY-DRIVEN DISEASES. NEURODEGENERATIVE DISORDERS ARE CHARACTERIZED BY THE PROGRESSIVE LOSS OF CENTRAL AND/OR PERIPHERAL NERVOUS SYSTEM NEURONS. WITHIN THIS CONTEXT, NEUROINFLAMMATION COMES UP AS ONE OF THE MAIN FACTORS LINKED TO NEURODEGENERATION PROGRESSION. IN FACT, NEUROINFLAMMATION HAS BEEN RECOGNIZED AS AN OUTSTANDING FACTOR FOR ALZHEIMER'S DISEASE (AD), AMYOTROPHIC LATERAL SCLEROSIS (ALS), PARKINSON'S DISEASE (PD), AND MULTIPLE SCLEROSIS (MS). INTERESTINGLY, NEUROINFLAMMATORY DISEASES ARE CHARACTERIZED BY DRAMATIC CHANGES IN THE EPIGENETIC PROFILE, WHICH MIGHT PROVIDE NOVEL PROGNOSTIC AND THERAPEUTIC FACTORS TOWARDS NEUROINFLAMMATORY TREATMENT. DEEP CHANGES IN DNA AND HISTONE METHYLATION, ALONG WITH HISTONE ACETYLATION AND ALTERED NON-CODING RNA EXPRESSION, HAVE BEEN REPORTED AT THE ONSET OF INFLAMMATORY DISEASES. THE AIM OF THIS WORK IS TO REVIEW THE CURRENT KNOWLEDGE ON THIS FIELD. 2022 12 6124 33 THE EPIGENETIC MECHANISMS INVOLVED IN CHRONIC PAIN IN RODENTS: A MINI- REVIEW. CHRONIC PAIN IS A COMMON DISTRESSING NEUROLOGICAL DISORDER AND ABOUT 30% OF THE GLOBAL POPULATION SUFFERS FROM IT. IN ADDITION TO BEING HIGHLY PREVALENT, CHRONIC PAIN CAUSES A HEAVY ECONOMIC AND SOCIAL BURDEN. ALTHOUGH SUBSTANTIAL PROGRESS HAS BEEN ACHIEVED TO DISSECT THE UNDERLYING MECHANISM OF CHRONIC PAIN IN THE PAST FEW DECADES, THE INCIDENCE AND TREATMENT OF THIS NEUROLOGICAL ILLNESS IS YET NOT PROPERLY MANAGED IN CLINICAL PRACTICE. WHILE NERVE INJURY-, CHEMOTHERAPY- OR INFLAMMATION-INDUCED FUNCTIONAL REGULATION OF GENE EXPRESSION IN THE DORSAL ROOT GANGLION AND SPINAL CORD ARE EXTENSIVELY REPORTED TO BE INVOLVED IN THE PATHOGENIC PROCESS OF CHRONIC PAIN, THE SPECIFIC MECHANISM OF THESE ALTERED TRANSCRIPTIONAL PROFILE STILL REMAINS UNCLEAR. RECENT STUDIES HAVE SHOWN THAT EPIGENETIC MECHANISMS, INCLUDING DNA/RNA METHYLATION, HISTONE MODIFICATION AND CIRCULAR RNAS REGULATION, ARE INVOLVED IN THE OCCURRENCE AND DEVELOPMENT OF CHRONIC PAIN. IN THIS REVIEW, WE PROVIDE A DESCRIPTION OF RESEARCH ON THE ROLE OF EPIGENETIC MECHANISM IN CHRONIC PAIN, SUMMARIZE THE LATEST CLINICAL AND PRECLINICAL ADVANCE IN THIS FIELD, AND PROPOSE THE POTENTIAL DIRECTIONS FOR FURTHER RESEARCH TO ELUCIDATE THE MOLECULAR MECHANISM UNDERLYING THE PATHOGENESIS OF CHRONIC PAIN. 2022 13 6257 26 THE MOLECULAR BASIS OF TOLERANCE. TOLERANCE IS DEFINED AS THE DIMINISHED RESPONSE TO ALCOHOL OR OTHER DRUGS OVER THE COURSE OF REPEATED OR PROLONGED EXPOSURE. THIS MECHANISM ALLOWS PHYSIOLOGICAL PROCESSES TO ACHIEVE STABILITY IN A CONSTANTLY CHANGING ENVIRONMENT. THE ONSET OF TOLERANCE MAY OCCUR WITHIN MINUTES, DURING A SINGLE EXPOSURE TO ALCOHOL (I.E., ACUTE TOLERANCE), OR OVER LONGER TIMEFRAMES AND WITH PROLONGED EXPOSURE TO ALCOHOL (I.E., RAPID OR CHRONIC TOLERANCE). CHANGES IN TOLERANCE INDUCED BY ALCOHOL MAY AFFECT SEVERAL PROCESSES AT THE MOLECULAR, CELLULAR, OR BEHAVIORAL LEVEL. THESE EFFECTS OFTEN ARE INTERRELATED AND MAY BE DIFFICULT TO SEPARATE. THIS ARTICLE DESCRIBES CHANGES AT THE MOLECULAR LEVEL THAT ARE RELATED TO THE ONSET OF ACUTE, RAPID, OR CHRONIC TOLERANCE. IT FOCUSES ON NEURONAL MEMBRANE-BOUND CHANNELS AND THE FACTORS THAT AFFECT THEIR FUNCTION AND PRODUCTION, SUCH AS MODIFICATION OF PROTEIN SYNTHESIS AND ACTIVITY, INTERACTION WITH THE MEMBRANE LIPID MICROENVIRONMENT, EPIGENETIC EFFECTS ON CYTOPLASMIC REGULATION, AND GENE TRANSCRIPTION. ALSO CONSIDERED IS THE GENETICS OF TOLERANCE. 2008 14 6866 32 [PAIN AND EMOTIONAL DYSREGULATION: CELLULAR MEMORY DUE TO PAIN]. GENETIC FACTORS ARE INVOLVED IN DETERMINANTS FOR THE RISK OF PSYCHIATRIC DISORDERS, AND NEUROLOGICAL AND NEURODEGENERATIVE DISEASES. CHRONIC PAIN STIMULI AND INTENSE PAIN HAVE EFFECTS AT A CELLULAR AND/OR GENE EXPRESSION LEVEL, AND WILL EVENTUALLY INDUCE "CELLULAR MEMORY DUE TO PAIN", WHICH MEANS THAT TISSUE DAMAGE, EVEN IF ONLY TRANSIENT, CAN ELICIT EPIGENETICALLY ABNORMAL TRANSCRIPTION/TRANSLATION AND POST-TRANSLATIONAL MODIFICATION IN RELATED CELLS DEPENDING ON THE DEGREE OR KIND OF INJURY OR ASSOCIATED CONDITIONS. SUCH CELL MEMORY/TRANSFORMATION DUE TO PAIN CAN CAUSE AN ABNORMALITY IN A FUNDAMENTAL INTRACELLULAR RESPONSE, SUCH AS A CHANGE IN THE THREE-DIMENSIONAL STRUCTURE OF DNA, TRANSCRIPTION, OR TRANSLATION. ON THE OTHER HAND, PAIN IS A MULTIDIMENSIONAL EXPERIENCE WITH SENSORY-DISCRIMINATIVE AND MOTIVATIONAL-AFFECTIVE COMPONENTS. RECENT HUMAN BRAIN IMAGING STUDIES HAVE EXAMINED DIFFERENCES IN ACTIVITY IN THE NUCLEUS ACCUMBENS BETWEEN CONTROLS AND PATIENTS WITH CHRONIC PAIN, AND HAVE REVEALED THAT THE NUCLEUS ACCUMBENS PLAYS A ROLE IN PREDICTING THE VALUE OF A NOXIOUS STIMULUS AND ITS OFFSET, AND IN THE CONSEQUENT CHANGES IN THE MOTIVATIONAL STATE. IN THIS REVIEW, WE PROVIDE A VERY BRIEF OVERVIEW OF A COMPREHENSIVE UNDERSTANDING OF CHRONIC PAIN ASSOCIATED WITH EMOTIONAL DYSREGULATION DUE TO TRANSCRIPTIONAL REGULATION, EPIGENETIC MODIFICATION AND MIRNA REGULATION. 2015 15 5811 31 STRESS - (SELF) EATING: EPIGENETIC REGULATION OF AUTOPHAGY IN RESPONSE TO PSYCHOLOGICAL STRESS. AUTOPHAGY IS A CONSTITUTIVE AND CYTOPROTECTIVE CATABOLIC PROCESS. ABERRATIONS IN AUTOPHAGY LEAD TO A MULTITUDE OF DEGENERATIVE DISORDERS, WITH NEURODEGENERATION BEING ONE OF THE MOST WIDELY STUDIED AUTOPHAGY-RELATED DISORDERS. WHILE THE FIELD HAS LARGELY BEEN FOCUSING ON THE CYTOSOLIC CONSTITUENTS AND PROCESSES OF AUTOPHAGY, RECENT STUDIES ARE INCREASINGLY APPRECIATING THE ROLE OF CHROMATIN MODIFICATIONS AND EPIGENETIC REGULATION IN AUTOPHAGY MAINTENANCE. AUTOPHAGY HAS BEEN IMPLICATED IN THE REGULATION OF NEUROGENESIS, AND DISRUPTION OF NEUROGENESIS IN RESPONSE TO PSYCHOLOGICAL STRESS IS A PROXIMAL RISK FACTOR FOR DEVELOPMENT OF NEUROPSYCHIATRIC DISORDERS SUCH AS MAJOR DEPRESSIVE DISORDER (MDD). IN THIS REVIEW, WE WILL DISCUSS THE REGULATION OF AUTOPHAGY IN NORMAL NEUROGENESIS AS WELL AS DURING CHRONIC PSYCHOLOGICAL STRESS, FOCUSING ON THE EPIGENETIC CONTROL OF AUTOPHAGY IN THESE CONTEXTS, AND ALSO HIGHLIGHT THE LACUNAE IN OUR UNDERSTANDING OF THIS PROCESS. THE SYSTEMATIC STUDY OF THESE REGULATORY MECHANISMS WILL PROVIDE A NOVEL THERAPEUTIC STRATEGY, BASED ON THE USE EPIGENETIC REGULATORS OF AUTOPHAGY TO ENHANCE NEUROGENESIS AND POTENTIALLY ALLEVIATE STRESS-RELATED BEHAVIORAL DISORDERS. 2019 16 3404 31 HOW EPIGENETICS IMPACTS ON HUMAN DISEASES. EPIGENETICS IS A RAPIDLY GROWING FIELD OF BIOLOGY THAT STUDIES THE CHANGES IN GENE EXPRESSION THAT ARE NOT DUE TO ALTERATIONS IN THE DNA SEQUENCE BUT RATHER THE CHEMICAL MODIFICATIONS OF DNA AND ITS ASSOCIATED PROTEINS. EPIGENETIC MECHANISMS CAN PROFOUNDLY INFLUENCE GENE EXPRESSION, CELL DIFFERENTIATION, TISSUE DEVELOPMENT, AND DISEASE SUSCEPTIBILITY. UNDERSTANDING EPIGENETIC CHANGES IS ESSENTIAL TO ELUCIDATE THE MECHANISMS UNDERLYING THE INCREASINGLY RECOGNIZED ROLE OF ENVIRONMENTAL AND LIFESTYLE FACTORS IN HEALTH AND DISEASE AND THE INTERGENERATIONAL TRANSMISSION OF PHENOTYPES. RECENT STUDIES SUGGEST EPIGENETICS MAY BE CRITICAL IN VARIOUS DISEASES, FROM CARDIOVASCULAR DISEASE AND CANCER TO NEURODEVELOPMENTAL AND NEURODEGENERATIVE DISORDERS. EPIGENETIC MODIFICATIONS ARE POTENTIALLY REVERSIBLE AND COULD PROVIDE NEW THERAPEUTIC AVENUES FOR TREATING THESE DISEASES USING EPIGENETIC MODULATORS. MOREOVER, EPIGENETICS PROVIDE INSIGHT INTO DISEASE PATHOGENESIS AND BIOMARKERS FOR DISEASE DIAGNOSIS AND RISK STRATIFICATION. NEVERTHELESS, EPIGENETIC INTERVENTIONS HAVE THE POTENTIAL FOR UNINTENDED CONSEQUENCES AND MAY POTENTIALLY LEAD TO INCREASED RISKS OF UNEXPECTED OUTCOMES, SUCH AS ADVERSE DRUG REACTIONS, DEVELOPMENTAL ABNORMALITIES, AND CANCER. THEREFORE, RIGOROUS STUDIES ARE ESSENTIAL TO MINIMIZE THE RISKS ASSOCIATED WITH EPIGENETIC THERAPIES AND TO DEVELOP SAFE AND EFFECTIVE INTERVENTIONS FOR IMPROVING HUMAN HEALTH. THIS ARTICLE PROVIDES A SYNTHETIC AND HISTORICAL VIEW OF THE ORIGIN OF EPIGENETICS AND SOME OF THE MOST RELEVANT ACHIEVEMENTS. 2023 17 2194 30 EPIGENETIC MODIFICATION IN NEUROPATHIC PAIN. NEUROPATHIC PAIN IS CHARACTERIZED BY COMPLICATED COMBINATION OF POSITIVE (E.G., HYPERALGESIA AND ALLODYNIA) AND NEGATIVE (E.G., HYPOESTHESIA AND HYPOALGESIA) SYMPTOMS, AND IS OFTEN REFRACTORY TO CONVENTIONAL PHARMACOLOGICAL AGENTS, INCLUDING MORPHINE. ALTHOUGH THE MOLECULAR MECHANISMS FOR POSITIVE SYMPTOMS ARE EXTENSIVELY STUDIED, THOSE FOR NEGATIVE SYMPTOMS ARE POORLY UNDERSTOOD. THERE IS CONVINCING EVIDENCE THAT ALTERED GENE EXPRESSION WITHIN PERIPHERAL AND CENTRAL NERVOUS SYSTEMS IS A KEY MECHANISM FOR NEUROPATHIC PAIN; HOWEVER, ITS TRANSCRIPTIONAL MECHANISMS ARE POORLY UNDERSTOOD. EPIGENETIC MODIFICATIONS, SUCH AS DNA METHYLATION AND HISTONE MODIFICATIONS (E.G., ACETYLATION, METHYLATION, AND PHOSPHORYLATION), ARE KNOWN TO CAUSE STABLE GENE EXPRESSION VIA CHROMATIN REMODELING. THESE MECHANISMS HAVE A ROLE NOT ONLY IN THE DETERMINATION OF DEVELOPMENTAL CELL FATES, BUT ALSO IN THE PHYSIOLOGICAL AND PATHOLOGICAL PROCESSES IN NERVOUS SYSTEM. MOREOVER, EPIGENETIC THERAPIES USING EPIGENETIC MODIFYING COMPOUNDS ARE PROGRESSIVELY ADVANCED IN THE TREATMENTS OF DIVERSE DISEASES, INCLUDING CANCER AND NEUROLOGICAL DISEASES. IMPORTANTLY, THERE IS EMERGING EVIDENCE THAT A VARIETY OF GENES UNDERGO EPIGENETIC REGULATION VIA DNA METHYLATION AND HISTONE MODIFICATIONS WITHIN PERIPHERAL AND CENTRAL NERVOUS SYSTEMS, THEREBY CONTRIBUTING TO THE ALTERATIONS IN BOTH PAIN SENSITIVITY AND PHARMACOLOGICAL EFFICACY IN NEUROPATHIC PAIN. IN THIS REVIEW, WE WILL HIGHLIGHT THE EPIGENETIC GENE REGULATION UNDERLYING NEUROPATHIC PAIN, ESPECIALLY FOCUSING ON THE NEGATIVE SYMPTOMS. MOREOVER, WE WILL DISCUSS WHETHER EPIGENETIC MECHANISMS CAN SERVE AS A POTENTIAL TARGET TO TREAT NEUROPATHIC PAIN. 2015 18 2611 23 EPIGENETICS: A PROMISING PARADIGM FOR BETTER UNDERSTANDING AND MANAGING PAIN. EPIGENETIC REGULATION OF GENE EXPRESSION IS A RAPIDLY GROWING AREA OF RESEARCH. CONSIDERING THE LONGEVITY AND PLASTICITY OF NEURONS, THE STUDIES ON EPIGENETIC PATHWAYS IN THE NERVOUS SYSTEM SHOULD BE OF SPECIAL INTEREST FOR BOTH EPIGENETICISTS AND NEUROSCIENTISTS. ACTIVATION OR INACTIVATION OF DIFFERENT EPIGENETIC PATHWAYS BECOMES MORE PRONOUNCED WHEN THE CELLS EXPERIENCE RAPID CHANGES IN THEIR ENVIRONMENT, AND SUCH CHANGES CAN BE EASILY CAUSED BY INJURY AND INFLAMMATION, RESULTING IN PAIN PERCEPTION OR DISTORTION OF PAIN PERCEPTION (EG, HYPERALGESIA). THEREFORE, IN THIS REGARD, THE FIELD OF PAIN IS AT AN ADVANTAGE TO STUDY THE EPIGENETIC PATHWAYS. MORE IMPORTANTLY, UNDERSTANDING PAIN FROM AN EPIGENETICS POINT OF VIEW WOULD PROVIDE A NEW PARADIGM FOR DEVELOPING DRUGS OR STRATEGIES FOR PAIN MANAGEMENT. IN THIS REVIEW, WE INTRODUCE BASIC CONCEPTS OF EPIGENETICS, INCLUDING CHROMATIN DYNAMICS, HISTONE MODIFICATIONS, DNA METHYLATION, AND RNA-INDUCED GENE SILENCING. IN ADDITION, WE PROVIDE EVIDENCE FROM PUBLISHED STUDIES SUGGESTING WIDE IMPLICATION OF DIFFERENT EPIGENETIC PATHWAYS WITHIN PAIN PATHWAYS. PERSPECTIVE: THIS ARTICLE PROVIDES A BRIEF OVERVIEW OF EPIGENETIC PATHWAYS FOR GENE REGULATION AND HIGHLIGHTS THEIR INVOLVEMENT IN PAIN. OUR GOAL IS TO EXPOSE THE READERS TO THESE CONCEPTS SO THAT PAIN-RELATED PHENOTYPES CAN BE INVESTIGATED FROM THE EPIGENETIC POINT OF VIEW. 2013 19 2523 35 EPIGENETICS AND THE TRANSITION FROM ACUTE TO CHRONIC PAIN. OBJECTIVE: THE OBJECTIVE OF THIS STUDY WAS TO REVIEW THE EPIGENETIC MODIFICATIONS INVOLVED IN THE TRANSITION FROM ACUTE TO CHRONIC PAIN AND TO IDENTIFY POTENTIAL TARGETS FOR THE DEVELOPMENT OF NOVEL, INDIVIDUALIZED PAIN THERAPEUTICS. BACKGROUND: EPIGENETICS IS THE STUDY OF HERITABLE MODIFICATIONS IN GENE EXPRESSION AND PHENOTYPE THAT DO NOT REQUIRE A CHANGE IN GENETIC SEQUENCE TO MANIFEST THEIR EFFECTS. ENVIRONMENTAL TOXINS, MEDICATIONS, DIET, AND PSYCHOLOGICAL STRESSES CAN ALTER EPIGENETIC PROCESSES SUCH AS DNA METHYLATION, HISTONE ACETYLATION, AND RNA INTERFERENCE. AS EPIGENETIC MODIFICATIONS POTENTIALLY PLAY AN IMPORTANT ROLE IN INFLAMMATORY CYTOKINE METABOLISM, STEROID RESPONSIVENESS, AND OPIOID SENSITIVITY, THEY ARE LIKELY KEY FACTORS IN THE DEVELOPMENT OF CHRONIC PAIN. ALTHOUGH OUR KNOWLEDGE OF THE HUMAN GENETIC CODE AND DISEASE-ASSOCIATED POLYMORPHISMS HAS GROWN SIGNIFICANTLY IN THE PAST DECADE, WE HAVE NOT YET BEEN ABLE TO ELUCIDATE THE MECHANISMS THAT LEAD TO THE DEVELOPMENT OF PERSISTENT PAIN AFTER NERVE INJURY OR SURGERY. DESIGN: THIS IS A FOCUSED LITERATURE REVIEW OF EPIGENETIC SCIENCE AND ITS RELATIONSHIP TO CHRONIC PAIN. RESULTS: SIGNIFICANT LABORATORY AND CLINICAL DATA SUPPORT THE NOTION THAT EPIGENETIC MODIFICATIONS ARE AFFECTED BY THE ENVIRONMENT AND LEAD TO DIFFERENTIAL GENE EXPRESSION. SIMILAR TO MECHANISMS INVOLVED IN THE DEVELOPMENT OF CANCER, NEURODEGENERATIVE DISEASE, AND INFLAMMATORY DISORDERS, THE LITERATURE ENDORSES AN IMPORTANT POTENTIAL ROLE FOR EPIGENETICS IN CHRONIC PAIN. CONCLUSIONS: EPIGENETIC ANALYSIS MAY IDENTIFY MECHANISMS CRITICAL TO THE DEVELOPMENT OF CHRONIC PAIN AFTER INJURY, AND MAY PROVIDE NEW PATHWAYS AND TARGET MECHANISMS FOR FUTURE DRUG DEVELOPMENT AND INDIVIDUALIZED MEDICINE. 2012 20 5926 26 TARGETING EPIGENETIC MECHANISMS FOR CHRONIC PAIN: A VALID APPROACH FOR THE DEVELOPMENT OF NOVEL THERAPEUTICS. CHRONIC PAIN IS A MULTIFACETED AND COMPLEX CONDITION. BROADLY CLASSIFIED INTO SOMATIC, VISCERAL, OR NEUROPATHIC PAIN, IT IS POORLY MANAGED DESPITE ITS PREVALENCE. CURRENT DRUGS USED FOR THE TREATMENT OF CHRONIC PAIN ARE LIMITED BY TOLERANCE WITH LONG-TERM USE, ABUSE POTENTIAL, AND MULTIPLE ADVERSE SIDE EFFECTS. THE PERSISTENT NATURE OF PAIN SUGGESTS THAT EPIGENETIC MACHINERY MAY BE A CRITICAL FACTOR DRIVING CHRONIC PAIN. IN THIS REVIEW, WE DISCUSS THE LATEST INSIGHTS INTO EPIGENETIC PROCESSES, INCLUDING DNA METHYLATION, HISTONE MODIFICATIONS, AND MICRORNAS, AND WE DESCRIBE THEIR INVOLVEMENT IN THE PATHOPHYSIOLOGY OF CHRONIC PAIN AND WHETHER EPIGENETIC MODIFICATIONS COULD BE APPLIED AS FUTURE THERAPEUTIC TARGETS FOR CHRONIC PAIN. WE PROVIDE EVIDENCE FROM EXPERIMENTAL MODELS AND TRANSLATIONAL RESEARCH IN HUMAN TISSUE THAT HAVE ENHANCED OUR UNDERSTANDING OF EPIGENETIC PROCESSES MEDIATING NOCICEPTION, AND WE THEN SPECULATE ON THE POTENTIAL FUTURE USE OF MORE SPECIFIC AND SELECTIVE AGENTS THAT TARGET EPIGENETIC MECHANISMS TO ATTENUATE PAIN. 2016