1 641 139 BIOMARKERS OF MAJOR DEPRESSIVE DISORDER: KNOWING IS HALF THE BATTLE. MAJOR DEPRESSIVE DISORDER (MDD) IS A HETEROGENEOUS DISEASE WHICH IS WHY THERE ARE CURRENTLY NO SPECIFIC METHODS TO ACCURATELY TEST THE SEVERITY, ENDOPHENOTYPE OR THERAPY RESPONSE. THIS LACK OF PROGRESS IS PARTLY ATTRIBUTED TO THE COM-PLEXITY AND VARIABILITY OF DEPRESSION, IN ASSOCIATION WITH ANALYTICAL VARIABILITY OF CLINICAL LITERATURE AND THE WIDE NUMBER OF THEORETICALLY COMPLEX BIOMARKERS. THE LITERATURE ACCESSIBLE, INDICATES THAT MARKERS INVOLVED IN INFLAMMATORY, NEURO-TROPHIC AND METABOLIC PROCESSES AND COMPONENTS OF NEUROTRANSMITTERS AND NEUROENDOCRINE SYSTEMS ARE RATHER STRONG INDICATORS TO BE CONSIDERED CLINICALLY AND CAN BE MEASURED THROUGH GENETIC AND EPIGENETIC, TRANSCRIPTOMIC AND PROTEOMIC, METABOLOMICS AND NEUROIMAGING ASSESSMENTS. PROMISING BIOLOGIC SYSTEMS/MARKERS FOUND WERE I.E., GROWTH BIOMARKERS, ENDOCRINE MARKERS, OXIDANT STRESS MARKERS, PROTEOMIC AND CHRONIC INFLAMMATORY MARKERS, ARE DISCUSSED IN THIS REVIEW. SEVERAL LINES OF EVIDENCE SUGGEST THAT A PORTION OF MDD IS A DOPAMINE AGONIST-RESPONSIVE SUBTYPE. THIS REVIEW ANALYZES CONCISE REPORTS ON THE PATHOPHYSIOLOGICAL BIOMARKERS OF MDD AND THERAPEUTIC REACTIONS VIA PERIPHERAL DEVELOPMENTAL FACTORS, INFLAMMATIVE CYTOKINES, ENDOCRINE FACTORS AND METABOLIC MARKERS. VARIOUS LITERATURES ALSO SUPPORT THAT ENDOCRINE AND METABOLISM CHANGES ARE ASSOCIATED WITH MDD. ACCUMULATING EVIDENCE SUGGESTS THAT AT LEAST A PORTION OF MDD PATIENTS SHOW CHARACTERISTICS PATHOLOGICAL CHANGES REGARDING DIFFERENT CLINICAL PATHOLOGICAL BIOMARKERS. BY THIS REVIEW WE SUM UP ALL THE DIFFERENT BIOMARKERS PLAYING AN IMPORTANT ROLE IN THE DETECTION OR TREATMENT OF THE DIFFERENT PATIENTS SUFFERING FROM MDD. THE REVIEW ALSO GIVES AN OVERVIEW OF DIFFERENT BIOMARKER'S PLAYING A POTENTIAL ROLE IN MODULATING EFFECT OF MDD. 2021 2 2231 33 EPIGENETIC MODIFICATIONS OF MAJOR DEPRESSIVE DISORDER. MAJOR DEPRESSIVE DISORDER (MDD) IS A CHRONIC DISEASE WHOSE NEUROLOGICAL BASIS AND PATHOPHYSIOLOGY REMAIN POORLY UNDERSTOOD. INITIALLY, IT WAS PROPOSED THAT GENETIC VARIATIONS WERE RESPONSIBLE FOR THE DEVELOPMENT OF THIS DISEASE. NEVERTHELESS, SEVERAL STUDIES WITHIN THE LAST DECADE HAVE PROVIDED EVIDENCE SUGGESTING THAT ENVIRONMENTAL FACTORS PLAY AN IMPORTANT ROLE IN MDD PATHOPHYSIOLOGY. ALTERATIONS IN EPIGENETICS MECHANISM, SUCH AS DNA METHYLATION, HISTONE MODIFICATION AND MICRORNA EXPRESSION COULD FAVOR MDD ADVANCE IN RESPONSE TO STRESSFUL EXPERIENCES AND ENVIRONMENTAL FACTORS. THE AIM OF THIS REVIEW IS TO DESCRIBE GENETIC ALTERATIONS, AND PARTICULARLY ALTERED EPIGENETIC MECHANISMS, THAT COULD BE DETERMINANTS FOR MDD PROGRESS, AND HOW THESE ALTERATIONS MAY ARISE AS USEFUL SCREENING, DIAGNOSIS AND TREATMENT MONITORING BIOMARKERS OF DEPRESSIVE DISORDERS. 2016 3 2572 35 EPIGENETICS OF DEPRESSION. MAJOR DEPRESSIVE DISORDER (MDD) IS A LEADING CAUSE OF DISABILITY WORLDWIDE AND IS ASSOCIATED WITH POOR PSYCHOLOGICAL, MEDICAL, AND SOCIOECONOMIC OUTCOMES. ALTHOUGH MUCH HAS BEEN LEARNED ABOUT THE ETIOLOGY AND TREATMENT OPTIONS OF MDD OVER THE PAST DECADE, THERE REMAIN UNANSWERED QUESTIONS THAT POSE CHALLENGES TO IMPROVING ACUTE AND CHRONIC OUTCOMES FOR THOSE WITH MDD. MDD IS A CLINICALLY HETEROGENEOUS DISORDER. GENETIC STUDIES TO DATE HAVE INDICATED A NUMBER OF GENES, INCLUDING TRANSPORTERS, NEUROTRANSMITTERS, NEUROTROPHINS, AND THEIR ASSOCIATED SIGNALING NETWORKS THAT MAY PREDISPOSE INDIVIDUALS TO MDD AND MAY ALSO PREDICT TREATMENT OUTCOMES. HOWEVER, TWIN STUDIES INDICATE THAT GENES ACCOUNT FOR ONLY A SMALL DEGREE OF THE VARIATION IN MDD. THUS, OTHER MECHANISMS, THROUGH EPIGENETIC MARKS, MAY ACT TO FORM A MOLECULAR MEMORY OF PREVIOUS GENE-TO-ENVIRONMENT INTERACTIONS AND TO ESTABLISH VULNERABILITIES (OR, CONVERSELY, RESISTANCE) TO MDD. CURRENT EVIDENCE SUPPORTS A ROLE FOR PRE-, PERI-, AND EARLY POSTNATAL ADVERSITIES AND STRESSFUL LIFE EVENTS INTO ADULTHOOD AFFECTING EPIGENETIC PATTERNS, PROVIDING A MECHANISTIC FOUNDATION TO DEVELOP EPIGENETIC MARKS AS BIOMARKERS FOR MDD. THIS REVIEW PRESENTS THE EVIDENCE SUPPORTING A ROLE FOR EPIGENETIC EFFECTS IN MDD AND IN TREATMENT RESPONSE. WE ALSO DISCUSS THE CONTROVERSY BEHIND MODULATING EPIGENETIC MECHANISMS IN LONG-TERM ANTIDEPRESSANT PHARMACOTHERAPY. 2014 4 2963 28 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 2526 35 EPIGENETICS APPLIED TO PSYCHIATRY: CLINICAL OPPORTUNITIES AND FUTURE CHALLENGES. PSYCHIATRIC DISORDERS ARE CLINICALLY HETEROGENEOUS AND DEBILITATING CHRONIC DISEASES RESULTING FROM A COMPLEX INTERPLAY BETWEEN GENE VARIANTS AND ENVIRONMENTAL FACTORS. EPIGENETIC PROCESSES, SUCH AS DNA METHYLATION AND HISTONE POSTTRANSLATIONAL MODIFICATIONS, INSTRUCT THE CELL/TISSUE TO CORRECTLY INTERPRET EXTERNAL SIGNALS AND ADJUST ITS FUNCTIONS ACCORDINGLY. GIVEN THAT EPIGENETIC MODIFICATIONS ARE SENSITIVE TO ENVIRONMENT, STABLE, AND REVERSIBLE, EPIGENETIC STUDIES IN PSYCHIATRY COULD REPRESENT A PROMISING APPROACH TO BETTER UNDERSTANDING AND TREATING DISEASE. IN THE PRESENT REVIEW, WE AIM TO DISCUSS THE CLINICAL OPPORTUNITIES AND CHALLENGES ARISING FROM THE EPIGENETIC RESEARCH IN PSYCHIATRY. USING SELECTED EXAMPLES, WE FIRST RECAPITULATE KEY FINDINGS SUPPORTING THE ROLE OF ADVERSE LIFE EVENTS, ALONE OR IN COMBINATION WITH GENETIC RISK, IN EPIGENETIC PROGRAMMING OF NEUROPSYCHIATRIC SYSTEMS. EPIGENETIC STUDIES FURTHER REPORT ENCOURAGING FINDINGS ABOUT THE USE OF METHYLATION CHANGES AS DIAGNOSTIC MARKERS OF DISEASE PHENOTYPE AND PREDICTIVE TOOLS OF PROGRESSION AND RESPONSE TO TREATMENT. THEN WE DISCUSS THE POTENTIAL OF USING TARGETED EPIGENETIC PHARMACOTHERAPY, COMBINED WITH PSYCHOSOCIAL INTERVENTIONS, FOR FUTURE PERSONALIZED MEDICINE FOR PATIENTS. FINALLY, WE REVIEW THE METHODOLOGICAL LIMITATIONS THAT COULD HINDER INTERPRETATION OF EPIGENETIC DATA IN PSYCHIATRY. THEY MAINLY ARISE FROM HETEROGENEITY AT THE INDIVIDUAL AND TISSUE LEVEL AND REQUIRE FUTURE STRATEGIES IN ORDER TO REINFORCE THE BIOLOGICAL RELEVANCE OF EPIGENETIC DATA AND ITS TRANSLATIONAL USE IN PSYCHIATRY. OVERALL, WE SUGGEST THAT EPIGENETICS COULD PROVIDE NEW INSIGHTS INTO A MORE COMPREHENSIVE INTERPRETATION OF MENTAL ILLNESS AND MIGHT EVENTUALLY IMPROVE THE NOSOLOGY, TREATMENT, AND PREVENTION OF PSYCHIATRIC DISORDERS. 2018 6 2288 44 EPIGENETIC REGULATION IN MAJOR DEPRESSION AND OTHER STRESS-RELATED DISORDERS: MOLECULAR MECHANISMS, CLINICAL RELEVANCE AND THERAPEUTIC POTENTIAL. MAJOR DEPRESSIVE DISORDER (MDD) IS A CHRONIC, GENERALLY EPISODIC AND DEBILITATING DISEASE THAT AFFECTS AN ESTIMATED 300 MILLION PEOPLE WORLDWIDE, BUT ITS PATHOGENESIS IS POORLY UNDERSTOOD. THE HERITABILITY ESTIMATE OF MDD IS 30-40%, SUGGESTING THAT GENETICS ALONE DO NOT ACCOUNT FOR MOST OF THE RISK OF MAJOR DEPRESSION. ANOTHER FACTOR KNOWN TO ASSOCIATE WITH MDD INVOLVES ENVIRONMENTAL STRESSORS SUCH AS CHILDHOOD ADVERSITY AND RECENT LIFE STRESS. RECENT STUDIES HAVE EMERGED TO SHOW THAT THE BIOLOGICAL IMPACT OF ENVIRONMENTAL FACTORS IN MDD AND OTHER STRESS-RELATED DISORDERS IS MEDIATED BY A VARIETY OF EPIGENETIC MODIFICATIONS. THESE EPIGENETIC MODIFICATION ALTERATIONS CONTRIBUTE TO ABNORMAL NEUROENDOCRINE RESPONSES, NEUROPLASTICITY IMPAIRMENT, NEUROTRANSMISSION AND NEUROGLIA DYSFUNCTION, WHICH ARE INVOLVED IN THE PATHOPHYSIOLOGY OF MDD. FURTHERMORE, EPIGENETIC MARKS HAVE BEEN ASSOCIATED WITH THE DIAGNOSIS AND TREATMENT OF MDD. THE EVALUATION OF EPIGENETIC MODIFICATIONS HOLDS PROMISE FOR FURTHER UNDERSTANDING OF THE HETEROGENEOUS ETIOLOGY AND COMPLEX PHENOTYPES OF MDD, AND MAY IDENTIFY NEW THERAPEUTIC TARGETS. HERE, WE REVIEW PRECLINICAL AND CLINICAL EPIGENETIC FINDINGS, INCLUDING DNA METHYLATION, HISTONE MODIFICATION, NONCODING RNA, RNA MODIFICATION, AND CHROMATIN REMODELING FACTOR IN MDD. IN ADDITION, WE ELABORATE ON THE CONTRIBUTION OF THESE EPIGENETIC MECHANISMS TO THE PATHOLOGICAL TRAIT VARIABILITY IN DEPRESSION AND DISCUSS HOW SUCH MECHANISMS CAN BE EXPLOITED FOR THERAPEUTIC PURPOSES. 2023 7 1329 42 DEPRESSION ASSOCIATED WITH DIABETES: FROM PATHOPHYSIOLOGY TO TREATMENT. DIABETES IS A CHRONIC AND PROGRESSIVE SYNDROME COMMONLY ASSOCIATED WITH SEVERAL NEUROPSYCHIATRIC COMORBITIES, OF WHICH DEPRESSION IS THE MOST STUDIED. THE PREVALENCE OF DEPRESSION IS ABOUT TWO OR THREE TIMES HIGHER IN DIABETIC PATIENTS COMPARED TO THE GENERAL POPULATION. IT IS BELIEVED THAT THE DIABETES - DEPRESSION RELATION MAY BE BIDIRECTIONAL, I.E., THE DEPRESSION CAN LEAD TO DIABETES AND CONVERSELY DIABETES COULD FACILITATE THE EMERGENCE OF DEPRESSION. DEPRESSION IS ONE OF THE MOST NEGLECTED SYMPTOMS IN DIABETIC PATIENTS AND IS DIRECTLY LINKED WITH LOWERING OF QUALITY OF LIFE. THE TREATMENT OF DEPRESSION IN THESE PATIENTS IS STILL QUITE INEFFECTIVE AND IN MANY CASES TREATMENTREFRACTORY. FURTHERMORE, SOME OF THE FIRST CHOICE DRUGS USED TO TREAT THE DEPRESSION AFFECT THE BLOOD GLUCOSE CONTROL, AGGRAVATING THE HYPERGLYCEMIC STATE. THESE ISSUES UNDERSCORE THE URGENCY IN STUDIES SEARCHING FOR NEW PHARMACOLOGICAL TARGETS FOR THE TREATMENT OF DEPRESSION ASSOCIATED WITH DIABETES. FOR THIS, A BETTER UNDERSTANDING OF THE PATHOPHYSIOLOGY THAT RELATES THIS COMORBIDITY BECOMES CRITICAL. IN THIS RESPECT, THIS REVIEW WILL FOCUS ON SOME HYPOTHESES THAT HAVE BEEN PROPOSED TO EXPLAIN THE MECHANISMS UNDERLYING DEPRESSION ASSOCIATED WITH DIABETES, HIGHLIGHTING THE TREATMENT OPTIONS CURRENTLY AVAILABLE AND THEIR LIMITATIONS. AMONG THESE HYPOTHESES, WE WILL POINT OUT THE HYPERGLYCEMIA AS A PRIMARY METABOLIC CAUSE OF THE DEPRESSION DEVELOPMENT, THE INVOLVEMENT OF THE DYSREGULATION OF HYPOTHALAMIC PITUITARY-ADRENAL (HPA) AXIS AND OF NEUROTRANSMITTER SYSTEMS, SPECIALLY MONOAMINERGIC SYSTEM. BESIDES, THE ROLE OF OXIDATIVE STRESS, NEUROINFLAMMATION AND CELL DEATH, ESPECIALLY IN HIPPOCAMPUS AND PREFRONTAL CORTEX, BRAIN AREAS IMPORTANT FOR THE MEDIATION AND MODULATION OF EMOTIONAL BEHAVIOR WILL ALSO BE DISCUSSED. FINALLY, WE WILL BRING UP THE INFLUENCE OF THE EPIGENETIC REGULATION WITH RESPECT TO NEUROPSYCHIATRIC DISORDERS. 2016 8 6676 35 USING EPIGENETIC TOOLS TO INVESTIGATE ANTIDEPRESSANT RESPONSE. MAJOR DEPRESSIVE DISORDER IS A CHRONIC AND DEBILITATING ILLNESS. IT IS MOST COMMONLY TREATED WITH ANTIDEPRESSANT DRUGS, HOWEVER, AS THE MAJORITY OF PATIENTS DO NOT RESPOND ON THEIR FIRST TRIAL OR FOLLOWING SEVERAL ADEQUATE TRIALS, THERE IS GREAT INTEREST IN IDENTIFYING BIOLOGICAL FACTORS THAT MAY HELP SELECT THE MOST APPROPRIATE TREATMENT FOR EACH PATIENT AND IN UNDERSTANDING BIOLOGICAL PROCESSES THAT MEDIATE TREATMENT RESPONSE. EPIGENETIC FACTORS, SUCH AS NON-CODING RNAS (NCRNAS), HOLD POTENTIAL AS BIOMARKERS OF ANTIDEPRESSANT RESPONSE. IN THIS CHAPTER, WE REVIEW KEY METHODOLOGICAL CONSIDERATIONS WHEN INVESTIGATING NCRNA BIOMARKERS, INCLUDING BIOLOGICAL SAMPLES AND TECHNOLOGIES WHICH HAVE BEEN USED IN THESE STUDIES. SECONDLY, WE SUMMARIZE FINDINGS FROM STUDIES INVESTIGATING NCRNAS IN ANTIDEPRESSANT TREATMENT RESPONSE. FINALLY, WE DISCUSS SOME OF THE FUTURE DIRECTIONS WHICH WILL BE NECESSARY FOR THE DEVELOPMENT OF CLINICALLY RELEVANT EPIGENETIC TOOLS. 2018 9 1736 29 EARLY DETECTION AND PREVENTION OF SCHIZOPHRENIC PSYCHOSIS-A REVIEW. PSYCHOTIC DISORDERS OFTEN RUN A CHRONIC COURSE AND ARE ASSOCIATED WITH A CONSIDERABLE EMOTIONAL AND SOCIAL IMPACT FOR PATIENTS AND THEIR RELATIVES. THEREFORE, EARLY RECOGNITION, COMBINED WITH THE POSSIBILITY OF PREVENTIVE INTERVENTION, IS URGENTLY WARRANTED SINCE THE DURATION OF UNTREATED PSYCHOSIS (DUP) SIGNIFICANTLY DETERMINES THE FURTHER COURSE OF THE DISEASE. IN ADDITION TO ESTABLISHED DIAGNOSTIC TOOLS, NEUROBIOLOGICAL FACTORS IN THE DEVELOPMENT OF SCHIZOPHRENIC PSYCHOSES ARE INCREASINGLY BEING INVESTIGATED. IT IS SHOWN THAT NUMEROUS MOLECULAR ALTERATIONS ALREADY EXIST BEFORE THE CLINICAL ONSET OF THE DISEASE. AS SCHIZOPHRENIC PSYCHOSES ARE NOT ELICITED BY A SINGLE MUTATION IN THE DEOXYRIBONUCLEIC ACID (DNA) SEQUENCE, EPIGENETICS LIKELY CONSTITUTE THE MISSING LINK BETWEEN ENVIRONMENTAL INFLUENCES AND DISEASE DEVELOPMENT AND COULD POTENTIALLY SERVE AS A BIOMARKER. THE RESULTS FROM TRANSCRIPTOMIC AND PROTEOMIC STUDIES POINT TO A DYSREGULATED IMMUNE SYSTEM, LIKELY EVOKED BY EPIGENETIC ALTERATIONS. DESPITE THE INCREASING KNOWLEDGE OF THE NEUROBIOLOGICAL MECHANISMS INVOLVED IN THE DEVELOPMENT OF PSYCHOTIC DISORDERS, FURTHER RESEARCH EFFORTS WITH LARGE POPULATION-BASED STUDY DESIGNS ARE NEEDED TO IDENTIFY SUITABLE BIOMARKERS. IN CONCLUSION, A COMBINATION OF BLOOD EXAMINATIONS, FUNCTIONAL IMAGING TECHNIQUES, ELECTROENCEPHALOGRAPHY (EEG) INVESTIGATIONS AND POLYGENIC RISK SCORES SHOULD BE CONSIDERED AS THE BASIS FOR PREDICTING HOW SUBJECTS WILL TRANSITION INTO MANIFEST PSYCHOSIS. 2021 10 4321 28 MICRORNAS IN MAJOR DEPRESSIVE DISORDER. MAJOR DEPRESSIVE DISORDER (MDD) IS A SEVERE AND CHRONIC PSYCHIATRIC DISORDER WITH A HIGH PREVALENCE IN THE POPULATION. ALTHOUGH OUR UNDERSTANDING OF ITS PATHOPHYSIOLOGICAL MECHANISMS HAS SIGNIFICANTLY INCREASED OVER THE YEARS, AVAILABLE TREATMENTS STILL PRESENT SEVERAL LIMITATIONS AND ARE NOT EFFECTIVE TO ALL MDD PATIENTS. EPIGENETIC MECHANISMS HAVE RECENTLY BEEN SUGGESTED TO PLAY KEY ROLES IN MDD PATHOGENESIS AND TREATMENT, INCLUDING THE EFFECTS OF SMALL NONCODING RNAS KNOWN AS MICRORNAS (MIRNAS). MIRNAS CAN MODULATE GENE EXPRESSION POSTTRANSCRIPTIONALLY BY INTERFERING WITH THE STABILITY AND TRANSLATION OF MESSENGER RNA MOLECULES AND ARE ALSO KNOWN TO CROSS-TALK WITH OTHER EPIGENETIC MECHANISMS. IN THIS REVIEW, WE WILL SUMMARIZE AND DISCUSS RECENT FINDINGS OF ALTERATIONS IN MIRNAS IN TISSUES OF PATIENTS WITH MDD AND EVIDENCE OF TREATMENT-INDUCED EFFECTS IN THESE MOLECULES. 2019 11 6260 28 THE MOLECULAR NEUROBIOLOGY OF CHRONIC PAIN-INDUCED DEPRESSION. THE INCREASING NUMBER OF INDIVIDUALS WITH COMORBIDITIES POSES AN URGENT NEED TO IMPROVE THE MANAGEMENT OF PATIENTS WITH MULTIPLE CO-EXISTING DISEASES. AMONG THESE COMORBIDITIES, CHRONIC PAIN AND MOOD DISORDERS, TWO LONG-LASTING DISABLING CONDITIONS THAT SIGNIFICANTLY REDUCE THE QUALITY OF LIFE, COULD BE CITED FIRST. THE RECENT DEVELOPMENT OF ANIMAL MODELS ACCELERATED THE STUDIES FOCUSING ON THE UNDERLYING MECHANISMS OF THE CHRONIC PAIN AND DEPRESSION/ANXIETY COMORBIDITY. THIS REVIEW PROVIDES AN OVERVIEW OF CLINICAL AND PRE-CLINICAL STUDIES PERFORMED OVER THE PAST TWO DECADES ADDRESSING THE MOLECULAR ASPECTS OF THE COMORBID RELATIONSHIP OF CHRONIC PAIN AND DEPRESSION. WE THUS FOCUSED ON THE STUDIES THAT INVESTIGATED THE MOLECULAR CHARACTERISTICS OF THE COMORBID RELATIONSHIP BETWEEN CHRONIC PAIN AND MOOD DISORDERS, ESPECIALLY MAJOR DEPRESSIVE DISORDERS, FROM THE GENETIC AND EPIGENETIC POINT OF VIEW TO KEY NEUROMODULATORS WHICH HAVE BEEN SHOWN TO PLAY AN IMPORTANT ROLE IN THIS COMORBIDITY. 2019 12 6791 27 [DOES THE NUMBER OF PATIENTS WITH AUTOIMMUNE DISORDERS AND THE FREQUENCY OF AUTOIMMUNE DISEASES INCREASE?]. AUTOIMMUNE DISEASES GENERALLY BELONG TO THE RARE DISEASES, HOWEVER, SOME OF THEM ARE FREQUENT IN THE POPULATION. IN THE PRESENT WORK THE AUTHORS ANALYSE WHETHER CAN ANY INCREASE BE OBSERVED IN THE NUMBER OF PATIENTS SUFFERING FROM AUTOIMMUNE DISEASES AND WHETHER DO THE FREQUENCY OF CERTAIN AUTOIMMUNE DISORDERS INCREASE. DUE MAINLY TO EPIGENETIC FACTORS THE INCIDENCE OF AUTOIMMUNE DISEASES ARE INCREASING, THEREFORE THERE ARE MORE PATIENTS RECOGNISED WITH PARTICULAR DISORDERS. ON THE OTHER HAND THE INCIDENCE IS INCREASED BY IMPROVING DIAGNOSTIC POSSIBILITIES, BY THE USE OF MORE SPECIFIC AND SENSITIVE CLASSIFICATION CRITERIA AND MORE SOPHISTICATED LABORATORY TESTS, RESULTED IN THE RECOGNITION OF MILDER AND ATYPICAL DISEASE VARIANTS AS WELL. THE PREVALENCE IS ALSO INCREASING IN CONSEQUENCE OF NOVEL IMMUNE SUPPRESSIVE THERAPEUTIC POSSIBILITIES AND THE CONSEQUENT IMPROVEMENT OF SURVIVAL IN THE MOST OF THESE DISEASES. BESIDES, MORE AND MORE DISEASES HAVE BEEN REVEALED TO HAVE AUTOIMMUNE BACKGROUND, AND LOT OF NEW AUTOIMMUNE SYNDROMES, DISEASES HAVE BEEN CHARACTERISED RECENTLY. THIS INCREASES THE NUMBER OF THE KNOWN AUTOIMMUNE RHEUMATIC DISORDERS WITH A CONSEQUENT INCREASE IN THE NUMBER OF AUTOIMMUNE PATIENTS. ASSIGNED TO THE INCREASING NUMBER OF VARIABLE CHRONIC AUTOIMMUNE DISORDERS, AND THE INCREASING NUMBER OF DISABLED PATIENTS WITH SUCH DISEASES INCREASING MEDICAL AND SOCIAL ATTENTION HAS TO BE FOCUSED ON. 2007 13 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 14 5164 36 PRECLINICAL AND CLINICAL EVIDENCE OF DNA METHYLATION CHANGES IN RESPONSE TO TRAUMA AND CHRONIC STRESS. EXPOSURE TO CHRONIC STRESS, EITHER REPEATED SEVERE ACUTE OR MODERATE SUSTAINED STRESS, IS ONE OF THE STRONGEST RISK FACTORS FOR THE DEVELOPMENT OF PSYCHOPATHOLOGIES SUCH AS POST-TRAUMATIC STRESS DISORDER AND DEPRESSION. CHRONIC STRESS IS LINKED WITH SEVERAL LASTING BIOLOGICAL CONSEQUENCES, PARTICULARLY TO THE STRESS ENDOCRINE SYSTEM BUT ALSO AFFECTING INTERMEDIATE PHENOTYPES SUCH AS BRAIN STRUCTURE AND FUNCTION, IMMUNE FUNCTION, AND BEHAVIOR. ALTHOUGH GENETIC PREDISPOSITION CONFERS A PROPORTION OF THE RISK, THE MOST RELEVANT MOLECULAR MECHANISMS DETERMINING THOSE SUSCEPTIBLE AND RESILIENT TO THE EFFECTS OF STRESS AND TRAUMA MAY BE EPIGENETIC. EPIGENETICS REFERS TO THE MECHANISMS THAT REGULATE GENOMIC INFORMATION BY DYNAMICALLY CHANGING THE PATTERNS OF TRANSCRIPTION AND TRANSLATION OF GENES. MOUNTING EVIDENCE FROM PRECLINICAL RODENT AND CLINICAL POPULATION STUDIES STRONGLY SUPPORT THAT EPIGENETIC MODIFICATIONS CAN OCCUR IN RESPONSE TO TRAUMATIC AND CHRONIC STRESS. HERE, WE DISCUSS THIS LITERATURE EXAMINING STRESS-INDUCED EPIGENETIC CHANGES IN PRECLINICAL MODELS AND CLINICAL COHORTS OF STRESS AND TRAUMA OCCURRING EARLY IN LIFE OR IN ADULTHOOD. WE HIGHLIGHT THAT A COMPLEX RELATIONSHIP BETWEEN THE TIMING OF ENVIRONMENTAL STRESSORS AND GENETIC PREDISPOSITIONS LIKELY MEDIATE THE RESPONSE TO CHRONIC STRESS OVER TIME, AND THAT A BETTER UNDERSTANDING OF EPIGENETIC CHANGES IS NEEDED BY FURTHER INVESTIGATIONS IN LONGITUDINAL AND POSTMORTEM BRAIN CLINICAL COHORTS. 2017 15 6211 35 THE INTERPLAY BETWEEN OXIDATIVE STRESS, EXERCISE, AND PAIN IN HEALTH AND DISEASE: POTENTIAL ROLE OF AUTONOMIC REGULATION AND EPIGENETIC MECHANISMS. OXIDATIVE STRESS CAN BE INDUCED BY VARIOUS STIMULI AND ALTERED IN CERTAIN CONDITIONS, INCLUDING EXERCISE AND PAIN. ALTHOUGH MANY STUDIES HAVE INVESTIGATED OXIDATIVE STRESS IN RELATION TO EITHER EXERCISE OR PAIN, THE LITERATURE PRESENTS CONFLICTING RESULTS. THEREFORE, THIS REVIEW CRITICALLY DISCUSSES EXISTING LITERATURE ABOUT THIS TOPIC, AIMING TO PROVIDE A CLEAR OVERVIEW OF KNOWN INTERACTIONS BETWEEN OXIDATIVE STRESS, EXERCISE, AND PAIN IN HEALTHY PEOPLE AS WELL AS IN PEOPLE WITH CHRONIC PAIN, AND TO HIGHLIGHT POSSIBLE CONFOUNDING FACTORS TO KEEP IN MIND WHEN REFLECTING ON THESE INTERACTIONS. IN ADDITION, AUTONOMIC REGULATION AND EPIGENETIC MECHANISMS ARE PROPOSED AS POTENTIAL MECHANISMS OF ACTION UNDERLYING THE INTERPLAY BETWEEN OXIDATIVE STRESS, EXERCISE, AND PAIN. THIS REVIEW HIGHLIGHTS THAT THE RELATION BETWEEN OXIDATIVE STRESS, EXERCISE, AND PAIN IS POORLY UNDERSTOOD AND NOT STRAIGHTFORWARD, AS IT IS DEPENDENT ON THE CHARACTERISTICS OF EXERCISE, BUT ALSO ON WHICH POPULATION IS INVESTIGATED. TO BE ABLE TO COMPARE STUDIES ON THIS TOPIC, STRICT GUIDELINES SHOULD BE DEVELOPED TO LIMIT THE EFFECT OF SEVERAL CONFOUNDING FACTORS. THIS WAY, THE TRUE INTERPLAY BETWEEN OXIDATIVE STRESS, EXERCISE, AND PAIN, AND THE UNDERLYING MECHANISMS OF ACTION CAN BE REVEALED AND VALIDATED VIA INDEPENDENT STUDIES. 2020 16 3676 37 INFLAMMATION AND NEUTROPHIL IMMUNOSENESCENCE IN HEALTH AND DISEASE: TARGETED TREATMENTS TO IMPROVE CLINICAL OUTCOMES IN THE ELDERLY. DESPITE INCREASING LONGEVITY, MANY OLD PEOPLE ARE NOT IN GOOD HEALTH. THERE HAS BEEN AN INCREASE IN THE PREVALENCE OF AGE-ASSOCIATED MULTI-MORBIDITY (TWO OR MORE CHRONIC CONDITIONS IN THE SAME PERSON). ALSO, SEVERE INFECTIONS, SUCH AS PNEUMONIA, REMAIN SIGNIFICANT CAUSES OF MORTALITY AND MORBIDITY IN THIS AGING GROUP. MANY CHRONIC HEALTH CONDITIONS SHARE RISK FACTORS SUCH AS INCREASING AGE, SMOKING, A SEDENTARY LIFE STYLE AND BEING PART OF A LOWER SOCIOECONOMIC GROUP. HOWEVER, DESPITE THIS, MULTI-MORBIDITIES OFTEN CO-OCCUR MORE COMMONLY THAN WOULD BE PREDICTED. THIS HAS LED TO THE HYPOTHESIS THAT THEY SHARE COMMON UNDERLYING MECHANISMS. THIS IS AN IMPORTANT CONCEPT, FOR IF IT WERE TRUE, TREATMENTS COULD BE DEVISED WHICH TARGET THESE COMMON PATHWAYS AND IMPROVE A NUMBER OF AGE-ASSOCIATED HEALTH CONDITIONS. MANY CHRONIC ILLNESSES ASSOCIATED WITH MULTI-MORBIDITY AND SEVERE INFECTIONS ARE CHARACTERIZED BY AN ABNORMAL AND SUSTAINED INFLAMMATORY RESPONSE, WITH NEUTROPHILS BEING KEY EFFECTOR CELLS IN THE PATHOLOGICAL PROCESS. STUDIES HAVE DESCRIBED ABERRANT NEUTROPHIL FUNCTIONS ACROSS THESE CONDITIONS, AND SOME HAVE HIGHLIGHTED POTENTIAL MECHANISMS FOR ALTERED CELL BEHAVIOURS WHICH APPEAR SHARED ACROSS DISEASE STATES. IT HAS BEEN SUGGESTED THAT ALTERED FUNCTIONS MAY REPRESENT NEUTROPHIL "SENESCENCE". THIS REVIEW CONSIDERS HOW AND WHY NEUTROPHIL FUNCTIONS CHANGE AS THE CELL AGES, AND HOW AND WHY NEUTROPHIL FUNCTIONS CHANGE AS THE HOST AGES IN HEALTH AND DISEASE AND DISCUSSES WHETHER NEUTROPHIL FUNCTIONS COULD BE TARGETED TO IMPROVE HEALTH OUTCOMES IN OLDER ADULTS. 2018 17 738 29 CANCER SUSCEPTIBILITY: EPIGENETIC MANIFESTATION OF ENVIRONMENTAL EXPOSURES. CANCER IS A DISEASE THAT RESULTS FROM BOTH GENETIC AND EPIGENETIC CHANGES. DISCORDANT PHENOTYPES AND VARYING INCIDENCES OF COMPLEX DISEASES SUCH AS CANCER IN MONOZYGOTIC TWINS AS WELL AS GENETICALLY IDENTICAL LABORATORY ANIMALS HAVE LONG BEEN ATTRIBUTED TO DIFFERENCES IN ENVIRONMENTAL EXPOSURES. ACCUMULATING EVIDENCE INDICATES, HOWEVER, THAT DISPARITIES IN GENE EXPRESSION RESULTING FROM VARIABLE MODIFICATIONS IN DNA METHYLATION AND CHROMATIN STRUCTURE IN RESPONSE TO THE ENVIRONMENT ALSO PLAY A ROLE IN DIFFERENTIAL SUSCEPTIBILITY TO DISEASE. DESPITE A GROWING CONSENSUS ON THE IMPORTANCE OF EPIGENETICS IN THE ETIOLOGY OF CHRONIC HUMAN DISEASES, THE GENES MOST PRONE TO EPIGENETIC DYSREGULATION ARE INCOMPLETELY DEFINED. MOREOVER, NEITHER THE ENVIRONMENTAL AGENTS MOST STRONGLY AFFECTING THE EPIGENOME NOR THE CRITICAL WINDOWS OF VULNERABILITY TO ENVIRONMENTALLY INDUCED EPIGENETIC ALTERATIONS ARE ADEQUATELY CHARACTERIZED. THESE MAJOR DEFICITS IN KNOWLEDGE MARKEDLY IMPAIR OUR ABILITY TO UNDERSTAND FULLY THE ETIOLOGY OF CANCER AND THE IMPORTANCE OF THE EPIGENOME IN DIAGNOSING AND PREVENTING THIS DEVASTATING DISEASE. 2007 18 3108 24 GENOMICS OF PAIN IN OSTEOARTHRITIS. OSTEOARTHRITIS (OA) ACCOUNTS FOR THE MAJORITY OF THE DISEASE BURDEN FOR MUSCULOSKELETAL DISORDERS AND IS ONE OF THE LEADING CAUSES OF DISABILITY WORLDWIDE. THIS DISABILITY IS THE RESULT NOT OF THE CARTILAGE LOSS THAT DEFINES OA RADIOGRAPHICALLY, BUT OF THE CHRONIC PAIN WHOSE PRESENCE DEFINES SYMPTOMATIC OA. IT IS BECOMING CLEAR THAT MANY GENES, EACH WITH A SMALL EFFECT SIZE, CONTRIBUTE TO THE RISK OF DEVELOPING OA. HOWEVER, THE GENETICS OF OA PAIN ARE ONLY JUST STARTING TO BE EXPLORED. THIS REVIEW WILL DESCRIBE THE FIRST GENES TO HAVE BEEN IDENTIFIED IN GENOMIC STUDIES OF OA PAIN, AS WELL AS THE POSSIBLE DUAL ROLES OF GENES PREVIOUSLY IDENTIFIED IN GENOMIC STUDIES OF OA IN THE CONTEXT OF PAIN. DIFFICULTIES ASSOCIATED WITH ATTEMPTING TO CHARACTERISE THE GENETICS OF OA PAIN WILL BE DISCUSSED AND PROMISING FUTURE AVENUES OF RESEARCH INTO GENETIC AND EPIGENETIC FACTORS AFFECTING OA PAIN DESCRIBED. 2013 19 2404 33 EPIGENETIC RESEARCH IN MULTIPLE SCLEROSIS: PROGRESS, CHALLENGES, AND OPPORTUNITIES. MULTIPLE SCLEROSIS (MS) IS A CHRONIC INFLAMMATORY AND DEMYELINATING DISEASE OF THE CENTRAL NERVOUS SYSTEM. MS LIKELY RESULTS FROM A COMPLEX INTERPLAY BETWEEN PREDISPOSING CAUSAL GENE VARIANTS (THE STRONGEST INFLUENCE COMING FROM HLA CLASS II LOCUS) AND ENVIRONMENTAL RISK FACTORS SUCH AS SMOKING, INFECTIOUS MONONUCLEOSIS, AND LACK OF SUN EXPOSURE/VITAMIN D. HOWEVER, LITTLE IS KNOWN ABOUT THE MECHANISMS UNDERLYING MS DEVELOPMENT AND PROGRESSION. MOREOVER, THE CLINICAL HETEROGENEITY AND VARIABLE RESPONSE TO TREATMENT REPRESENT ADDITIONAL CHALLENGES TO A COMPREHENSIVE UNDERSTANDING AND EFFICIENT TREATMENT OF DISEASE. EPIGENETIC PROCESSES, SUCH AS DNA METHYLATION AND HISTONE POSTTRANSLATIONAL MODIFICATIONS, INTEGRATE INFLUENCES FROM THE GENES AND THE ENVIRONMENT TO REGULATE GENE EXPRESSION ACCORDINGLY. STUDYING EPIGENETIC MODIFICATIONS, WHICH ARE STABLE AND REVERSIBLE, MAY PROVIDE AN ALTERNATIVE APPROACH TO BETTER UNDERSTAND AND MANAGE DISEASE. WE HERE AIM TO REVIEW FINDINGS FROM EPIGENETIC STUDIES IN MS AND FURTHER DISCUSS THE CHALLENGES AND CLINICAL OPPORTUNITIES ARISING FROM EPIGENETIC RESEARCH, MANY OF WHICH APPLY TO OTHER DISEASES WITH SIMILAR COMPLEX ETIOLOGY. A GROWING BODY OF EVIDENCE SUPPORTS A ROLE OF EPIGENETIC PROCESSES IN THE MECHANISMS UNDERLYING IMMUNE PATHOGENESIS AND NERVOUS SYSTEM DYSFUNCTION IN MS. HOWEVER, DISPARITIES BETWEEN STUDIES SHED LIGHT ON THE NEED TO CONSIDER POSSIBLE CONFOUNDERS AND METHODOLOGICAL LIMITATIONS FOR A BETTER INTERPRETATION OF THE DATA. NEVERTHELESS, TRANSLATIONAL USE OF EPIGENETICS MIGHT OFFER NEW OPPORTUNITIES IN EPIGENETIC-BASED DIAGNOSTICS AND THERAPEUTIC TOOLS FOR A PERSONALIZED CARE OF MS PATIENTS. 2017 20 2107 31 EPIGENETIC FACTORS IN SCHIZOPHRENIA: MECHANISMS AND EXPERIMENTAL APPROACHES. SCHIZOPHRENIA IS A CHRONIC MENTAL DISORDER THAT IS STILL POORLY UNDERSTOOD DESPITE DECADES OF STUDY. MANY FACTORS HAVE BEEN FOUND TO CONTRIBUTE TO THE PATHOGENESIS, INCLUDING NEURODEVELOPMENTAL DISTURBANCE, GENETIC RISK, AND ENVIRONMENTAL INSULT, BUT NO SINGLE ROOT CAUSE HAS EMERGED. WHILE EVIDENCE FROM TWIN STUDIES SUGGESTS A STRONG HERITABLE COMPONENT, FEW INDIVIDUAL LOCI HAVE BEEN IDENTIFIED IN GENOMEWIDE SCREENS, SUGGESTING A ROLE FOR EPIGENETIC EFFECTS. RATHER, LARGE NUMBERS OF WEAKLY ACTING LOCI MAY CUMULATIVELY INCREASE DISEASE RISK, INCLUDING SEVERAL MAPPING TO EPIGENETIC PATHWAYS. IN THIS REVIEW, WE DISCUSS MECHANISMS OF EPIGENETIC REGULATION AND EVIDENCE FOR AN EPIGENETIC CONTRIBUTION TO DISEASE PHENOTYPE. WE FURTHER DESCRIBE THE RANGE OF EXPERIMENTAL TOOLS CURRENTLY AVAILABLE TO STUDY EPIGENETIC EFFECTS ASSOCIATED WITH THE DISEASE. 2019