1 190 148 ACETYL-L-CARNITINE IN PAINFUL PERIPHERAL NEUROPATHY: A SYSTEMATIC REVIEW. ACETYL-L-CARNITINE (ALC) HAS SHOWN A NEUROPROTECTIVE EFFECT IN PATIENTS WITH PERIPHERAL NEUROPATHIES OF DIFFERENT ETIOLOGIES. PRECLINICAL STUDIES DEMONSTRATED A CENTRAL ANTI-NOCICEPTIVE ACTION, BOTH IN NEUROPATHIC AND NOCICEPTIVE PAIN MODELS. THE PRESENT REVIEW AIMS TO PROVIDE THE KNOWLEDGE ON THE EFFICACY OF ALC IN PATIENTS WITH PAINFUL PERIPHERAL NEUROPATHY, BASED ON THE EVIDENCE. CONSISTENT WITH THE PRISMA STATEMENT, AUTHORS SEARCHED PUBMED, EMBASE AND THE COCHRANE DATABASE OF SYSTEMATIC REVIEWS FOR RELEVANT PAPERS, INCLUDING THOSE ISSUED BEFORE APRIL 2018. TWO AUTHORS INDEPENDENTLY SELECTED STUDIES FOR INCLUSION AND DATA EXTRACTION: ONLY TRIALS INCLUDING PATIENTS WITH A DIAGNOSIS OF PERIPHERAL NEUROPATHY AND INVOLVING AT LEAST 10 PATIENTS WERE CONSIDERED FOR THE PURPOSES OF THIS REVIEW. FOURTEEN CLINICAL TRIALS WERE REVISED, TO PROVIDE THE LEVEL OF EVIDENCE FOR NEUROPATHY. TO ASSESS THE GLOBAL EFFICACY OF ALC IN PAINFUL PERIPHERAL NEUROPATHY, A META-ANALYSIS OF FOUR RANDOMIZED CONTROLLED TRIALS WAS PERFORMED. MEAN DIFFERENCE IN PAIN REDUCTION AS MEASURED ON A 10-CM VAS, AND 95% CIS WERE USED FOR POOLING CONTINUOUS DATA FROM EACH TRIAL. FOUR RANDOMIZED CONTROLLED TRIALS TESTED ALC IN PATIENTS WITH NEUROPATHY SECONDARY TO DIABETES AND TO ANTIRETROVIRAL THERAPY FOR HIV. COMPARED TO PLACEBO, ALC PRODUCED A SIGNIFICANT PAIN REDUCTION EQUAL TO 20.2% (95% CI: 8.3%-32.1%, P<0.0001) WITH RESPECT TO BASELINE. CLINICAL TRIALS ALSO SHOWED BENEFICIAL EFFECTS ON NERVE CONDUCTION PARAMETERS AND NERVE FIBER REGENERATION, WITH A GOOD SAFETY PROFILE. THESE DATA INDICATE THAT ALC PROVIDES AN EFFECTIVE AND SAFE TREATMENT IN PATIENTS WITH PAINFUL PERIPHERAL NEUROPATHY. WE RECOMMEND FURTHER STUDIES TO ASSESS THE OPTIMAL DOSE AND DURATION OF THE THERAPEUTIC EFFECT (ALSO AFTER TREATMENT WITHDRAWAL). 2019 2 2108 34 EPIGENETIC FACTORS RELATED TO LOW BACK PAIN: A SYSTEMATIC REVIEW OF THE CURRENT LITERATURE. LOW BACK PAIN (LBP) IS ONE OF THE MOST COMMON CAUSES OF PAIN AND DISABILITY. AT PRESENT, TREATMENT AND INTERVENTIONS FOR ACUTE AND CHRONIC LOW BACK PAIN OFTEN FAIL TO PROVIDE SUFFICIENT LEVELS OF PAIN RELIEF, AND FULL FUNCTIONAL RESTORATION CAN BE CHALLENGING. CONSIDERING THE SIGNIFICANT SOCIO-ECONOMIC BURDEN AND RISK-TO-BENEFIT RATIO OF MEDICAL AND SURGICAL INTERVENTION IN LOW BACK PAIN PATIENTS, THE IDENTIFICATION OF RELIABLE BIOMARKERS SUCH AS EPIGENETIC FACTORS ASSOCIATED WITH LOW BACK PAIN COULD BE USEFUL IN CLINICAL PRACTICE. THE AIM OF THIS STUDY WAS TO REVIEW THE AVAILABLE LITERATURE REGARDING THE EPIGENETIC FACTORS ASSOCIATED WITH LOW BACK PAIN. THIS REVIEW WAS CARRIED OUT IN ACCORDANCE WITH PREFERENTIAL REPORTING ITEMS FOR SYSTEMATIC REVIEWS AND META-ANALYSES (PRISMA) GUIDELINES. THE SEARCH WAS CARRIED OUT IN OCTOBER 2022. ONLY PEER-REVIEWED ARTICLES WERE CONSIDERED FOR INCLUSION. FOURTEEN STUDIES WERE INCLUDED AND SHOWED PROMISING RESULTS IN TERMS OF RELIABLE MARKERS. EPIGENETIC MARKERS FOR LBP HAVE THE POTENTIAL TO SIGNIFICANTLY MODIFY DISEASE MANAGEMENT. MOST RECENT EVIDENCE SUGGESTS THAT EPIGENETICS IS A MORE PROMISING FIELD FOR THE IDENTIFICATION OF FACTORS ASSOCIATED WITH LBP, OFFERING A RATIONALE FOR FURTHER INVESTIGATION IN THIS FIELD WITH THE LONG-TERM GOAL OF FINDING EPIGENETIC BIOMARKERS THAT COULD CONSTITUTE BIOLOGICAL TARGETS FOR DISEASE MANAGEMENT AND TREATMENT. 2023 3 2093 41 EPIGENETIC EFFECTS FOLLOWING ACUTE AND CHRONIC EXERCISE IN CARDIOVASCULAR DISEASE: A SYSTEMATIC REVIEW. INTRODUCTION: ACUTE EXERCISE AND EXERCISE TRAINING MAY CONFER EPIGENETIC MODIFICATIONS IN HEALTHY SUBJECTS. EPIGENETIC EFFECTS AFTER EXERCISE HAVE BEEN SHOWED IN PATIENTS WITH CARDIOVASCULAR DISEASE. THE AIM OF THIS SYSTEMATIC REVIEW WAS TO SUMMARIZE THE EVIDENCE FROM AVAILABLE CLINICAL TRIALS THAT STUDY EPIGENETIC ADAPTATIONS AFTER EXERCISE IN PATIENTS WITH CARDIOVASCULAR DISEASE. METHODS: THE SEARCH STRATEGY WAS PERFORMED IN PUBMED AND CENTRAL DATABASES ON ARTICLES PUBLISHED UNTIL SEPTEMBER 2020. STUDIES WITH TITLES AND ABSTRACTS RELEVANT TO EXERCISE EPIGENETIC MODIFICATION APPLIED TO CARDIOVASCULAR PATIENTS WERE FULLY EXAMINED. INCLUSION AND EXCLUSION CRITERIA WERE UTILIZED FOR STUDIES SCREENING. QUALITY ASSESSMENT WITH PEDRO SCALE AND EVALUATION BY TWO INDEPENDENT REVIEWERS WAS PERFORMED. RESULTS: OF THE 1714 ARTICLES RETRIEVED, 88 ARTICLES WERE ASSESSED FOR ELIGIBILITY CRITERIA AND 8 ARTICLES MATCHED OUR SEARCH CRITERIA AND FINALLY INCLUDED IN THE SYSTEMATIC ANALYSIS. THE ACUTE EXERCISE EPIGENETIC (MIRNAS) EFFECTS WERE ASSESSED IN THREE STUDIES AND THE CHRONIC EXERCISE TRAINING EFFECTS (MIRNAS AND DNA METHYLATION) IN SIX STUDIES. THE RESULTS HAVE SHOWN THAT THERE IS POSSIBLY AN ACUTE SIGNIFICANT EXERCISE EFFECT ON EPIGENETIC TARGETS WHICH IS MORE EVIDENT AFTER CHRONIC EXERCISE TRAINING. CONCLUSIONS: BY THE PRESENT SYSTEMATIC REVIEW, WE PROVIDE PRELIMINARY EVIDENCE OF BENEFICIAL EPIGENETIC ADAPTATIONS FOLLOWING ACUTE AND CHRONIC EXERCISE IN PATIENTS WITH CARDIOVASCULAR DISEASE. MORE CONTROLLED STUDIES ARE NEEDED TO CONFIRM SUCH EVIDENCE. 2021 4 5129 28 POSTOPERATIVE PAIN AND ANALGESIA: IS THERE A GENETIC BASIS TO THE OPIOID CRISIS? BACKGROUND: MULTIPLE FACTORS HAVE BEEN IMPLICATED IN DETERMINING WHY CERTAIN PATIENTS HAVE INCREASED POSTOPERATIVE PAIN, WITH THE POTENTIAL TO DEVELOP CHRONIC PAIN. THE PURPOSE OF THIS STUDY WAS TO: 1) IDENTIFY AND DESCRIBE GENES THAT AFFECT POSTOPERATIVE PAIN PERCEPTION AND CONTROL; 2) ADDRESS MODIFIABLE RISK FACTORS THAT RESULT IN EPIGENETIC ALTERED RESPONSES TO PAIN; AND 3) CHARACTERIZE DIFFERENCES IN PAIN SENSITIVITY AND THRESHOLDS BETWEEN OPIOID-NAIVE AND OPIOID-DEPENDENT PATIENTS. MATERIALS AND METHODS: THREE ELECTRONIC DATABASES WERE USED TO CONDUCT THE LITERATURE SEARCH: PUBMED, EBSCO HOST, AND SCOPUS. A TOTAL OF 372 ABSTRACTS WERE REVIEWED, OF WHICH 46 STUDIES WERE DEEMED RELEVANT AND ARE INCLUDED IN THIS REVIEW. RESULTS: SPECIFIC GENE ALTERATIONS THAT WERE SHOWN TO AFFECT POSTOPERATIVE PAIN CONTROL INCLUDED SINGLE NUCLEOTIDE POLYMORPHISMS IN THE MU, KAPPA, AND DELTA OPIOID RECEPTORS, ION CHANNEL GENES, CYTOTOXIC T-CELLS, GLUTAMATE RECEPTORS AND CYTOKINE GENES, AMONG OTHERS. ALCOHOLISM, OBESITY, AND SMOKING WERE ALL LINKED WITH GENETIC POLYMORPHISMS THAT ALTERED PAIN SENSITIVITY. OPIOID ABUSE WAS FOUND TO BE ASSOCIATED WITH A POORER RESPONSE TO ANALGESICS POSTOPERATIVELY, AS WELL AS A RISK FOR PRESCRIPTION OVERDOSE. CONCLUSION: ALTHOUGH PAIN PERCEPTION HAS MULTIPLE COMPLEX INFLUENCES, THE GREATEST VARIABILITY SEEN IN RESPONSE TO OPIOIDS AMONG POSTOPERATIVE PATIENTS KNOWN TO DATE CAN BE TRACED TO GENETIC DIFFERENCES IN OPIOID METABOLISM. FURTHER STUDY IS NEEDED TO DETERMINE THE CLINICAL SIGNIFICANCE OF THESE GENETIC ASSOCIATIONS. 2018 5 1998 35 EPIGENETIC AND MIRNA EXPRESSION CHANGES IN PEOPLE WITH PAIN: A SYSTEMATIC REVIEW. ACCUMULATING EVIDENCE SUGGESTS THAT EPIGENETIC MECHANISMS MAY HOLD GREAT POTENTIAL IN THE FIELD OF PAIN. WE SYSTEMATICALLY REVIEWED THE LITERATURE EXPLORING EPIGENETIC MECHANISMS IN PEOPLE WITH PAIN. FOUR DATABASES HAVE BEEN INTERROGATED: MEDLINE, THE COCHRANE CENTRAL REGISTER OF CONTROLLED TRIAL, SCOPUS, AND WEB OF SCIENCE, FOLLOWING PRISMA GUIDELINES IN CONDUCTING STUDY SELECTION AND ASSESSMENT. THIRTY-SEVEN STUDIES WERE INCLUDED. STUDIES EXPLORED EPIGENETICS IN CONDITIONS SUCH AS FIBROMYALGIA, CRPS, NEUROPATHIES, OR OSTEOARTHRITIS. RESEARCH FOCUSSED ON GENOME-WIDE AND GENE-SPECIFIC DNA METHYLATION, AND MIRNA EXPRESSION. BIOINFORMATICS ANALYSES EXPLORING MIRNA-ASSOCIATED MOLECULAR PATHWAYS WERE ALSO PERFORMED. SEVERAL GENES ALREADY KNOWN FOR THEIR ROLE IN PAIN (BDNF, HDAC4, PRKG1, IL-17, TNFRSF13B, ETC.), AND SEVERAL MIRNAS LINKED TO INFLAMMATORY REGULATION, NOCICEPTIVE SIGNALLING AND PROTEIN KINASES FUNCTIONS HAVE BEEN FOUND TO DIFFER SIGNIFICANTLY BETWEEN PEOPLE WITH CHRONIC PAIN AND HEALTHY CONTROLS. ALTHOUGH THE STUDIES INCLUDED WERE CROSS-SECTIONAL IN NATURE, AND NO CONCLUSION ON CAUSAL LINKS BETWEEN EPIGENETIC CHANGES AND PAIN COULD BE DRAWN, WE SUMMARISED THE LARGE AMOUNT OF DATA AVAILABLE IN LITERATURE ON THE TOPIC, HIGHLIGHTING RESULTS THAT HAVE BEEN REPLICATED BY INDEPENDENT INVESTIGATIONS. THE FIELD OF PAIN EPIGENETICS APPEARS VERY EXCITING AND HAS ALL THE POTENTIAL TO LEAD TO REMARKABLE SCIENTIFIC ADVANCES. HOWEVER, HIGH-QUALITY, WELL-POWERED, LONGITUDINAL STUDIES ARE WARRANTED. PERSPECTIVE: THOUGH MORE HIGH-QUALITY RESEARCH IS NEEDED, AVAILABLE RESEARCH EXPLORING EPIGENETIC MECHANISMS OR MIRNAS IN PEOPLE WITH PAIN SHOWS THAT GENES REGULATING SYNAPTIC PLASTICITY AND EXCITABILITY, PROTEIN KINASES, AND ELEMENTS OF THE IMMUNE SYSTEM MIGHT HOLD GREAT POTENTIAL IN UNDERSTANDING THE PATHOPHYSIOLOGY OF DIFFERENT CONDITIONS. 2020 6 6458 35 TIME COURSE OF DNA METHYLATION IN PAIN CONDITIONS: FROM EXPERIMENTAL MODELS TO HUMANS. BACKGROUND AND OBJECTIVE: THROUGHOUT THE LAST DECADE, RESEARCH HAS UNCOVERED ASSOCIATIONS BETWEEN PAIN AND EPIGENETIC ALTERATIONS CAUSED BY ENVIRONMENTAL FACTORS. SPECIFICALLY, STUDIES HAVE DEMONSTRATED CORRELATIONS BETWEEN PAIN CONDITIONS AND ALTERED DNA METHYLATION PATTERNS. THUS, DNA METHYLATION HAS BEEN REVEALED AS A POSSIBLE MODULATOR OR CONTRIBUTOR TO PAIN CONDITIONS, PROVIDING A POTENTIAL THERAPEUTIC TARGET FOR TREATMENT BY DNA METHYLATION MODIFICATION. TO DEVELOP SUCH TREATMENTS, IT IS NECESSARY TO CLARIFY A WIDE NUMBER OF ASPECTS ON HOW DNA METHYLATION AFFECTS PAIN PERCEPTION; FIRST AND FOREMOST, THE TEMPORAL DYNAMICS. THE OBJECTIVE OF THE PRESENT REVIEW IS TO PROVIDE AN OVERVIEW OF CURRENT KNOWLEDGE ON TEMPORAL DYNAMICS OF DNA METHYLATION IN RESPONSE TO PAIN, AND TO INVESTIGATE IF A TIMEFRAME CAN BE ESTABLISHED BASED ON THE DATA OF CURRENTLY PUBLISHED STUDIES. DATABASES AND DATA TREATMENT: PUBMED, MEDLINE, GOOGLE SCHOLAR AND EMBASE WERE SEARCHED COMPREHENSIVELY FOR STUDIES OF DNA METHYLATION IN NEUROPATHIC, INFLAMMATORY AND ALTERNATIVE ANIMAL PAIN MODELS, AND IN CHRONIC PAIN PATIENTS INCLUDING COMPLEX REGIONAL PAIN SYNDROME, CHRONIC POSTSURGICAL PAIN, CHRONIC WIDESPREAD PAIN, FIBROMYALGIA AND CROHN'S DISEASE. RESULTS: WE IDENTIFIED 34 ARTICLES HIGHLIGHTING VARIATIONS IN TEMPORAL DYNAMICS OF DNA METHYLATION ACROSS SPECIES AND BETWEEN DIFFERENT TYPES OF PAIN. THESE STUDIES REPRESENT A STARTING POINT TO UNCOVER NEW INSIGHTS IN THE DNA METHYLATION TIME COURSE IN PAIN. CONCLUSIONS: NO TIMEFRAME CAN CURRENTLY BE MADE FOR THE DNA METHYLATION RESPONSE TO PAIN IN ANY OF THE REVIEWED CONDITIONS, HIGHLIGHTING AN IMPORTANT FOCUS AREA FOR FUTURE RESEARCH. 2021 7 5039 29 PHARMACOGENETICS OF CHRONIC PAIN MANAGEMENT. OBJECTIVE: THE EXPERIENCE OF CHRONIC PAIN IS ONE OF THE COMMONEST REASONS INDIVIDUALS SEEK MEDICAL ATTENTION, MAKING THE MANAGEMENT OF CHRONIC PAIN A MAJOR ISSUE IN CLINICAL PRACTICE. DRUG METABOLISM AND RESPONSES ARE AFFECTED BY MANY FACTORS, WITH GENETIC VARIATIONS OFFERING ONLY A PARTIAL EXPLANATION OF AN INDIVIDUAL'S RESPONSE. THERE IS A PAUCITY OF EVIDENCE FOR THE BENEFITS OF PHARMACOGENETIC TESTING IN THE CONTEXT OF PAIN MANAGEMENT. DESIGN AND METHODS: WE REVIEWED THE LITERATURE BETWEEN 2000 AND 2013, AND REFERENCES CITED THEREIN, USING VARIOUS KEYWORDS RELATED TO PAIN MANAGEMENT, PHARMACOLOGY AND PHARMACOGENETICS. RESULTS: OPIOIDS CONTINUE TO BE THE MAINSTAY OF CHRONIC PAIN MANAGEMENT. SEVERAL NON-OPIOID BASED THERAPIES, SUCH AS TREATMENT WITH CANNABINOIDS, GENE THERAPY AND EPIGENETIC-BASED APPROACHES ARE NOW AVAILABLE FOR THESE PATIENTS. ADJUVANT THERAPIES WITH ANTIDEPRESSANTS, BENZODIAZEPINES OR ANTICONVULSANTS CAN ALSO BE USEFUL IN MANAGING PAIN. CURRENTLY, LABORATORY MONITORING OF PAIN MANAGEMENT PATIENTS, IF PERFORMED, IS LARGELY THROUGH URINE DRUG MEASUREMENTS. CONCLUSIONS: DRUG HALF-LIFE CALCULATIONS CAN BE USED AS FUNCTIONAL MARKERS OF THE CUMULATIVE EFFECT OF PHARMACOGENETICS AND DRUG-DRUG INTERACTIONS. ASSESSMENT OF HALF-LIFE AND THERAPEUTIC EFFECTS MAY BE MORE USEFUL THAN GENETIC TESTING IN PREVENTING ADVERSE DRUG REACTIONS TO PAIN MEDICATIONS, WHILE ENSURING EFFECTIVE ANALGESIA. DEFINITIVE, MASS SPECTROMETRY-BASED METHODS, CAPABLE OF MEASURING PARENT DRUG AND METABOLITE LEVELS, ARE THE MOST USEFUL ASSAYS FOR THIS PURPOSE. URINE DRUG MEASUREMENTS DO NOT NECESSARILY CORRELATE WITH SERUM DRUG CONCENTRATIONS OR THERAPEUTIC EFFECTS. THEREFORE, THEY ARE LIMITED IN THEIR USE IN MONITORING EFFICACY AND TOXICITY. 2014 8 191 33 ACETYL-L-CARNITINE: FROM A BIOLOGICAL CURIOSITY TO A DRUG FOR THE PERIPHERAL NERVOUS SYSTEM AND BEYOND. ACETYL-L-CARNITINE (ALC) IS A MOLECULE DERIVED FROM ACETYLATION OF CARNITINE IN THE MITOCHONDRIA. CARNITINE ACETYLATION ENABLES THE FUNCTION OF COA AND FACILITATES ELIMINATION OF OXIDATIVE PRODUCTS. BEYOND THIS METABOLIC ACTIVITY, ALC PROVIDES ACETYL GROUPS FOR ACETYLCHOLINE SYNTHESIS, EXERTS A CHOLINERGIC EFFECT AND OPTIMIZES THE BALANCE OF ENERGY PROCESSES. ACETYLCARNITINE SUPPLEMENTATION INDUCES NEUROPROTECTIVE, NEUROTROPHIC AND ANALGESIC EFFECTS IN THE PERIPHERAL NERVOUS SYSTEM. IN THE RECENT STUDIES, ALC, BY ACTING AS A DONOR OF ACETYL GROUPS TO NF-KB P65/RELA, ENHANCED THE TRANSCRIPTION OF THE GRM2 GENE ENCODING THE MGLU2 RECEPTORS, INDUCING LONG-TERM UPREGULATION OF THE MGLUR2, EVIDENCING THEREFORE THAT ITS LONG-TERM ANALGESIC EFFECTS ARE DEPENDENT ON EPIGENETIC MODIFICATIONS. SEVERAL STUDIES, INCLUDING DOUBLE-BLIND, PLACEBO-CONTROLLED, PARALLEL GROUP STUDIES AND FEW OPEN STUDIES SHOWED THE EFFECT OF ALC IN DISEASES CHARACTERIZED BY NEUROPATHIES AND NEUROPATHIC PAIN: THE STUDIES INCLUDED DIABETIC NEUROPATHY, HIV AND ANTIRETROVIRAL THERAPY-INDUCED NEUROPATHIES, NEUROPATHIES DUE TO COMPRESSION AND CHEMOTHERAPEUTIC AGENTS. DOUBLE-BLINDED STUDIES INVOLVED 1773 PATIENTS. STATISTICAL EVALUATIONS EVIDENCED REDUCTION OF PAIN, IMPROVEMENTS OF NERVE FUNCTION AND TROPHISM. IN CONCLUSION, ALC REPRESENTS A CONSISTENT THERAPEUTIC OPTION FOR PERIPHERAL NEUROPATHIES, AND ITS COMPLEX EFFECTS, NEUROTROPHIC AND ANALGESIC, BASED ON EPIGENETIC MECHANISM, OPEN NEW PATHWAYS IN THE STUDY OF PERIPHERAL NERVE DISEASE MANAGEMENT. 2013 9 4915 27 PAIN, ANALGESIA AND GENETICS. OBJECTIVES: IN THE CLINICAL SETTING, THERE IS MARKED INTERSUBJECT VARIABILITY IN THE INTENSITY OF PAIN REPORTED BY PATIENTS WITH APPARENTLY SIMILAR PAIN STATES, AS WELL AS WIDELY DIFFERING ANALGESIC DOSING REQUIREMENTS BETWEEN INDIVIDUALS TO PRODUCE SATISFACTORY PAIN RELIEF WITH TOLERABLE SIDE-EFFECTS. GENETIC AND ENVIRONMENTAL FACTORS AS WELL AS THEIR INTERACTION ARE IMPLICATED, AND THESE ARE DISCUSSED IN THIS REVIEW. KEY FINDINGS: PIONEERING WORK UNDERTAKEN IN MICE MORE THAN A DECADE AGO, SHOWED A STRONG GENETIC CONTRIBUTION TO LEVELS OF NOCICEPTION/HYPERSENSITIVITY AS WELL AS LEVELS OF ANTINOCICEPTION PRODUCED BY COMMONLY AVAILABLE ANALGESIC AGENTS. TO DATE MORE THAN 300 CANDIDATE 'PAIN' GENES HAVE BEEN IDENTIFIED AS POTENTIALLY CONTRIBUTING TO HERITABLE DIFFERENCES IN PAIN SENSITIVITY AND ANALGESIC RESPONSIVENESS IN ANIMALS AND HUMANS, WITH THIS INFORMATION AVAILABLE IN A PUBLICLY ACCESSIBLE DATABASE HTTP://WWW.JBLDESIGN.COM/JMOGIL/ENTER.HTML. SINCE THEN, MANY GENETIC ASSOCIATION STUDIES HAVE BEEN CONDUCTED IN HUMANS TO INVESTIGATE THE POSSIBILITY THAT SINGLE NUCLEOTIDE POLYMORPHISMS (SNPS) IN AN INDIVIDUAL GENE MAY EXPLAIN DRUG INEFFICACY OR EXCESSIVE TOXICITY EXPERIENCED BY A SMALL SUBSET OF THE WHOLE POPULATION WHO HAVE THE RARE ALLELE FOR A PARTICULAR SNP. SUMMARY: DESPITE THE FACT THAT SNPS IN MORE THAN 20 GENES THAT AFFECT PAIN SENSITIVITY OR CONTRIBUTE TO INTERINDIVIDUAL VARIABILITY IN RESPONSES TO ANALGESIC MEDICATIONS HAVE BEEN IDENTIFIED IN THE HUMAN GENOME, MUCH OF THE DATA IS CONFLICTING. APART FROM DEFICIENCIES IN THE DESIGN AND CONDUCT OF HUMAN GENETIC ASSOCIATION STUDIES, RECENT RESEARCH FROM OTHER FIELDS HAS IMPLICATED EPIGENETIC MECHANISMS THAT FACILITATE DYNAMIC GENE-ENVIRONMENT COMMUNICATION, AS A POSSIBLE EXPLANATION. 2011 10 6159 27 THE GENETICS AND EPIGENETICS OF FATIGUE. FATIGUE IS A COMMON SYMPTOM AND INCLUDES BOTH PHYSICAL AND MENTAL COMPONENTS. IT CAN BE ASSOCIATED WITH A VARIETY OF DIFFERENT SYNDROMES AND DISEASES, BUT IN MANY CASES IS NOT ASSOCIATED WITH OTHER COMORBID CONDITIONS. MOST HUMANS HAVE EXPERIENCED ACUTE FATIGUE IN RELATION TO DIFFERENT STRESSORS. ACUTE FATIGUE TYPICALLY DECREASES AS THE EFFECT OF THE TRIGGERING FACTOR IS REDUCED AND A NORMAL HOMEOSTATIC BALANCE IS RESTORED. FATIGUE THAT PERSISTS FOR 6 MONTHS OR MORE IS TERMED CHRONIC FATIGUE. CHRONIC FATIGUE (CF) IN COMBINATION WITH A MINIMUM OF 4 OF 8 SYMPTOMS AND THE ABSENCE OF DISEASES THAT COULD EXPLAIN THESE SYMPTOMS, CONSTITUTE THE CASE DEFINITION FOR CHRONIC FATIGUE SYNDROME. IN SPITE OF ITS PREVALENCE, THE BIOLOGY OF FATIGUE IS RELATIVELY POORLY UNDERSTOOD AND BIOLOGICAL MARKERS HAVE NOT YET BEEN IDENTIFIED. THIS LITERATURE SEARCH WAS PERFORMED IN PUBMED TO IDENTIFY RESEARCH ON THE GENETICS AND EPIGENETICS OF FATIGUE. PUBLICATIONS WERE INCLUDED IF FATIGUE WAS A MAJOR TOPIC AND THE TOPIC WAS COMBINED WITH GENETIC AND/OR EPIGENETIC MEASUREMENTS IN ADULT HUMANS. A TOTAL OF 40 PUBLICATIONS WERE IDENTIFIED. ALTHOUGH ALTERED FUNCTIONING IN THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS, THE SEROTONERGIC SYSTEM, AND ASSOCIATIONS WITH INFECTIOUS AGENTS HAVE BEEN IDENTIFIED, THE SEARCH FOR GENETIC OR EPIGENETIC MARKERS OF FATIGUE, EITHER IN THE CONTEXT OF CF OR CHRONIC FATIGUE SYNDROME (CFS) HAS BEEN RELATIVELY UNPRODUCTIVE OR, IN THE CASE OF EPIGENETICS, NONEXISTENT. ALTHOUGH SEVERAL STUDIES, BOTH HYPOTHESIS-TESTING AND HYPOTHESIS-GENERATING, HAVE BEEN PERFORMED TO SEARCH FOR BIOMARKERS, THEY HAVE MOSTLY BEEN UNDERPOWERED, RESTRICTED BY THE HETEROGENEITY OF THE PHENOTYPE, OR LIMITED BY AN UNSYSTEMATIC STUDY DESIGN. TO BE ABLE TO CONFIRM THE HYPOTHESIS THAT RISK FOR, OR LEVELS OF, FATIGUE ARE INFLUENCED BY THE GENETIC OR EPIGENETIC BACKGROUND OF AN INDIVIDUAL, STUDIES NEED TO BE BASED ON LARGER SAMPLE SIZES WITH A MORE CLEARLY DEFINED PHENOTYPE. STUDIES NEED TO FOCUS NOT ONLY ON THE INFLUENCE OF A SINGLE ASPECT SUCH AS SINGLE NUCLEOTIDE POLYMORPHISMS (SNPS) OR DIFFERENTIAL GENE EXPRESSION ON DISEASE RISK OR STATE, BUT ALSO ON THE SYSTEMS BIOLOGY BEHIND THE DISEASE IN COMBINATION WITH INFORMATION ON ENVIRONMENTAL INFLUENCES AND VALIDATION OF FINDINGS IN FUNCTIONAL STUDIES. 2010 11 1314 25 DELINEATING CONDITIONS AND SUBTYPES IN CHRONIC PAIN USING NEUROIMAGING. DIFFERENTIATING SUBTYPES OF CHRONIC PAIN STILL REMAINS A CHALLENGE-BOTH FROM A SUBJECTIVE AND OBJECTIVE POINT OF VIEW. PERSONALIZED MEDICINE IS THE CURRENT GOAL OF MODERN MEDICAL CARE AND IS LIMITED BY THE SUBJECTIVE NATURE OF PATIENT SELF-REPORTING OF SYMPTOMS AND BEHAVIORAL EVALUATION. PHYSIOLOGY-FOCUSED TECHNIQUES SUCH AS GENOME AND EPIGENETIC ANALYSES INFORM THE DELINEATION OF PAIN GROUPS; HOWEVER, EXCEPT UNDER RARE CIRCUMSTANCES, THEY HAVE DILUTED EFFECTS THAT AGAIN, SHARE A COMMON RELIANCE ON BEHAVIORAL EVALUATION. THE APPLICATION OF STRUCTURAL NEUROIMAGING TOWARDS DISTINGUISHING PAIN SUBTYPES IS A GROWING FIELD AND MAY INFORM PAIN-GROUP CLASSIFICATION THROUGH THE ANALYSIS OF BRAIN REGIONS SHOWING HYPERTROPHIC AND ATROPHIC CHANGES IN THE PRESENCE OF PAIN. ANALYTICAL TECHNIQUES SUCH AS MACHINE-LEARNING CLASSIFIERS HAVE THE CAPACITY TO PROCESS LARGE VOLUMES OF DATA AND DELINEATE DIAGNOSTICALLY RELEVANT INFORMATION FROM NEUROIMAGING ANALYSIS. THE ISSUE OF DEFINING A "BRAIN TYPE" IS AN EMERGING FIELD AIMED AT INTERPRETING OBSERVED BRAIN CHANGES AND DELINEATING THEIR CLINICAL IDENTITY/SIGNIFICANCE. IN THIS REVIEW, 2 CHRONIC PAIN CONDITIONS (MIGRAINE AND IRRITABLE BOWEL SYNDROME) WITH SIMILAR CLINICAL PHENOTYPES ARE COMPARED IN TERMS OF THEIR STRUCTURAL NEUROIMAGING FINDINGS. INDEPENDENT INVESTIGATIONS ARE COMPARED WITH FINDINGS FROM APPLICATION OF MACHINE-LEARNING ALGORITHMS. FINDINGS ARE DISCUSSED IN TERMS OF DIFFERENTIATING PATIENT SUBGROUPS USING NEUROIMAGING DATA IN PATIENTS WITH CHRONIC PAIN AND HOW THEY MAY BE APPLIED TOWARDS DEFINING A PERSONALIZED PAIN SIGNATURE THAT HELPS SEGREGATE PATIENT SUBGROUPS (EG, MIGRAINE WITH AND WITHOUT AURA, WITH OR WITHOUT NAUSEA; IRRITABLE BOWEL SYNDROME VS OTHER FUNCTIONAL GASTROINTESTINAL DISORDERS). 2019 12 5040 24 PHARMACOGENETICS OF PAIN AND ANALGESIA. PAIN SEVERITY RATINGS AND THE ANALGESIC DOSING REQUIREMENTS OF PATIENTS WITH APPARENTLY SIMILAR PAIN CONDITIONS MAY DIFFER CONSIDERABLY BETWEEN INDIVIDUALS. CONTRIBUTING FACTORS INCLUDE THOSE OF GENETIC AND ENVIRONMENTAL ORIGIN WITH EPIGENETIC MECHANISMS THAT ENABLE DYNAMIC GENE-ENVIRONMENT INTERACTION, MORE RECENTLY IMPLICATED IN PAIN MODULATION. INSIGHT INTO GENETIC FACTORS UNDERPINNING INTER-PATIENT VARIABILITY IN PAIN SENSITIVITY HAS COME FROM RODENT HERITABILITY STUDIES AS WELL AS FAMILIAL AGGREGATION AND TWIN STUDIES IN HUMANS. INDEED, MORE THAN 350 CANDIDATE PAIN GENES HAVE BEEN IDENTIFIED AS POTENTIALLY CONTRIBUTING TO HERITABLE DIFFERENCES IN PAIN SENSITIVITY. A LARGE NUMBER OF GENETIC ASSOCIATION STUDIES CONDUCTED IN PATIENTS WITH A VARIETY OF CLINICAL PAIN TYPES OR IN HUMANS EXPOSED TO EXPERIMENTALLY INDUCED PAIN STIMULI IN THE LABORATORY SETTING, HAVE EXAMINED THE IMPACT OF SINGLE-NUCLEOTIDE POLYMORPHISMS IN VARIOUS TARGET GENES ON PAIN SENSITIVITY AND/OR ANALGESIC DOSING REQUIREMENTS. HOWEVER, THE FINDINGS OF SUCH STUDIES HAVE GENERALLY FAILED TO REPLICATE OR HAVE BEEN ONLY PARTIALLY REPLICATED BY INDEPENDENT INVESTIGATORS. DEFICIENCIES IN STUDY CONDUCT INCLUDING USE OF SMALL SAMPLE SIZE, INAPPROPRIATE STATISTICAL METHODS AND INADEQUATE ATTENTION TO THE POSSIBILITY THAT BETWEEN-STUDY DIFFERENCES IN ENVIRONMENTAL FACTORS MAY ALTER PAIN PHENOTYPES THROUGH EPIGENETIC MECHANISMS, HAVE BEEN IDENTIFIED AS BEING SIGNIFICANT. 2012 13 3881 40 KETOGENIC DIETS AND THE NERVOUS SYSTEM: A SCOPING REVIEW OF NEUROLOGICAL OUTCOMES FROM NUTRITIONAL KETOSIS IN ANIMAL STUDIES. OBJECTIVES: KETOGENIC DIETS HAVE REPORTED EFFICACY FOR NEUROLOGICAL DYSFUNCTIONS; HOWEVER, THERE ARE LIMITED PUBLISHED HUMAN CLINICAL TRIALS ELUCIDATING THE MECHANISMS BY WHICH NUTRITIONAL KETOSIS PRODUCES THERAPEUTIC EFFECTS. THE PURPOSE OF THIS PRESENT STUDY WAS TO INVESTIGATE ANIMAL MODELS THAT REPORT VARIATIONS IN NERVOUS SYSTEM FUNCTION BY CHANGING FROM A STANDARD ANIMAL DIET TO A KETOGENIC DIET, SYNTHESISE THESE INTO BROAD THEMES, AND COMPARE THESE WITH MECHANISMS REPORTED AS TARGETS IN PAIN NEUROSCIENCE TO INFORM HUMAN CHRONIC PAIN TRIALS. METHODS: AN ELECTRONIC SEARCH OF SEVEN DATABASES WAS CONDUCTED IN JULY 2020. TWO INDEPENDENT REVIEWERS SCREENED STUDIES FOR ELIGIBILITY, AND DESCRIPTIVE OUTCOMES RELATING TO NERVOUS SYSTEM FUNCTION WERE EXTRACTED FOR A THEMATIC ANALYSIS, THEN SYNTHESISED INTO BROAD THEMES. RESULTS: IN TOTAL, 170 STUDIES FROM EIGHTEEN DIFFERENT DISEASE MODELS WERE IDENTIFIED AND GROUPED INTO FOURTEEN BROAD THEMES: ALTERATIONS IN CELLULAR ENERGETICS AND METABOLISM, BIOCHEMICAL, CORTICAL EXCITABILITY, EPIGENETIC REGULATION, MITOCHONDRIAL FUNCTION, NEUROINFLAMMATION, NEUROPLASTICITY, NEUROPROTECTION, NEUROTRANSMITTER FUNCTION, NOCICEPTION, REDOX BALANCE, SIGNALLING PATHWAYS, SYNAPTIC TRANSMISSION AND VASCULAR SUPPLY. DISCUSSION: THE MECHANISMS PRESENTED CENTRED AROUND THE REDUCTION OF INFLAMMATION AND OXIDATIVE STRESS AS WELL AS A REDUCTION IN NERVOUS SYSTEM EXCITABILITY. GIVEN THE MULTIPLE POTENTIAL MECHANISMS PRESENTED, IT IS LIKELY THAT MANY OF THESE ARE INVOLVED SYNERGISTICALLY AND UNDERGO ADAPTIVE PROCESSES WITHIN THE HUMAN BODY, AND CONTROLLED ANIMAL MODELS THAT LIMIT THE INVESTIGATION TO A PARTICULAR PATHWAY IN ISOLATION MAY REACH DIFFERING CONCLUSIONS. ATTENTION IS REQUIRED WHEN TRANSLATING THIS INFORMATION TO HUMAN CHRONIC PAIN POPULATIONS OWING TO THE LIMITATIONS OUTLINED FROM THE ANIMAL RESEARCH. 2022 14 5038 20 PHARMACOGENETICS OF CHRONIC PAIN AND ITS TREATMENT. THIS PAPER REVIEWS THE IMPACT OF GENETIC VARIABILITY OF DRUG METABOLIZING ENZYMES, TRANSPORTERS, RECEPTORS, AND PATHWAYS INVOLVED IN CHRONIC PAIN PERCEPTION ON THE EFFICACY AND SAFETY OF ANALGESICS AND OTHER DRUGS USED FOR CHRONIC PAIN TREATMENT. SEVERAL CANDIDATE GENES HAVE BEEN IDENTIFIED IN THE LITERATURE, WHILE THERE IS USUALLY ONLY LIMITED CLINICAL EVIDENCE SUBSTANTIATING FOR THE PENETRATION OF THE TESTING FOR THESE CANDIDATE BIOMARKERS INTO THE CLINICAL PRACTICE. FURTHER, THE PAIN-PERCEPTION REGULATION AND MODULATION ARE STILL NOT FULLY UNDERSTOOD, AND THUS MORE COMPLEX KNOWLEDGE OF GENETIC AND EPIGENETIC BACKGROUND FOR ANALGESIA WILL BE NEEDED PRIOR TO THE CLINICAL USE OF THE CANDIDATE GENETIC BIOMARKERS. 2013 15 6112 49 THE EPIGENETIC CLOCK AS A PREDICTOR OF DISEASE AND MORTALITY RISK: A SYSTEMATIC REVIEW AND META-ANALYSIS. BACKGROUND: AGEING IS ONE OF THE PRINCIPAL RISK FACTORS FOR MANY CHRONIC DISEASES. HOWEVER, THERE IS CONSIDERABLE BETWEEN-PERSON VARIATION IN THE RATE OF AGEING AND INDIVIDUAL DIFFERENCES IN THEIR SUSCEPTIBILITY TO DISEASE AND DEATH. EPIGENETIC MECHANISMS MAY PLAY A ROLE IN HUMAN AGEING, AND DNA METHYLATION AGE BIOMARKERS MAY BE GOOD PREDICTORS OF AGE-RELATED DISEASES AND MORTALITY RISK. THE AIMS OF THIS SYSTEMATIC REVIEW WERE TO IDENTIFY AND SYNTHESISE THE EVIDENCE FOR AN ASSOCIATION BETWEEN PERIPHERALLY MEASURED DNA METHYLATION AGE AND LONGEVITY, AGE-RELATED DISEASE, AND MORTALITY RISK. METHODS: A SYSTEMATIC SEARCH WAS CONDUCTED IN LINE WITH THE PREFERRED REPORTING ITEMS FOR SYSTEMATIC REVIEWS AND META-ANALYSES (PRISMA) GUIDELINES. USING RELEVANT SEARCH TERMS, MEDLINE, EMBASE, COCHRANE CENTRAL REGISTER OF CONTROLLED TRIALS, AND PSYCHINFO DATABASES WERE SEARCHED TO IDENTIFY ARTICLES MEETING THE INCLUSION CRITERIA. STUDIES WERE ASSESSED FOR BIAS USING JOANNA BRIGGS INSTITUTE CRITICAL APPRAISAL CHECKLISTS. DATA WAS EXTRACTED FROM STUDIES MEASURING AGE ACCELERATION AS A PREDICTOR OF AGE-RELATED DISEASES, MORTALITY OR LONGEVITY, AND THE FINDINGS FOR SIMILAR OUTCOMES COMPARED. USING REVIEW MANAGER 5.3 SOFTWARE, TWO META-ANALYSES (ONE PER EPIGENETIC CLOCK) WERE CONDUCTED ON STUDIES MEASURING ALL-CAUSE MORTALITY. RESULTS: TWENTY-THREE RELEVANT ARTICLES WERE IDENTIFIED, INCLUDING A TOTAL OF 41,607 PARTICIPANTS. FOUR STUDIES FOCUSED ON AGEING AND LONGEVITY, 11 ON AGE-RELATED DISEASE (CANCER, CARDIOVASCULAR DISEASE, AND DEMENTIA), AND 11 ON MORTALITY. THERE WAS SOME, ALTHOUGH INCONSISTENT, EVIDENCE FOR AN ASSOCIATION BETWEEN INCREASED DNA METHYLATION AGE AND RISK OF DISEASE. META-ANALYSES INDICATED THAT EACH 5-YEAR INCREASE IN DNA METHYLATION AGE WAS ASSOCIATED AN 8 TO 15% INCREASED RISK OF MORTALITY. CONCLUSION: DUE TO THE SMALL NUMBER OF STUDIES AND HETEROGENEITY IN STUDY DESIGN AND OUTCOMES, THE ASSOCIATION BETWEEN DNA METHYLATION AGE AND AGE-RELATED DISEASE AND LONGEVITY IS INCONCLUSIVE. INCREASED EPIGENETIC AGE WAS ASSOCIATED WITH MORTALITY RISK, BUT POSITIVE PUBLICATION BIAS NEEDS TO BE CONSIDERED. FURTHER RESEARCH IS NEEDED TO DETERMINE THE EXTENT TO WHICH DNA METHYLATION AGE CAN BE USED AS A CLINICAL BIOMARKER. 2019 16 6323 30 THE ROLE OF A POTENTIAL BIOMARKER IN PATIENTS WITH MIGRAINE: REVIEW AND NEW INSIGHTS. INTRODUCTION: THE SEARCH FOR AN IDEAL BIOMARKER FOR MIGRAINE HAS PERSISTED FOR A LONG TIME. THERE IS PLENTIFUL EVIDENCE OF POTENTIAL BIOMARKERS FOR MIGRAINE FOUND IN CEREBROSPINAL FLUID, BLOOD, AND SALIVA.AREAS COVERED: HEREIN, THE AUTHORS HIGHLIGHT AND DISCUSS THE MOST PROMISING CANDIDATES IN THE LITERATURE. AN ELECTRONIC SEARCH WAS PERFORMED FOR STUDIES PUBLISHED BETWEEN 2010 AND 2020 IN MEDLINE, PUBMED, AND EMBASE, RELATED TO POTENTIAL BIOMARKERS IN MIGRAINE PATIENTS, FOUND IN CEREBROSPINAL FLUID, SALIVA, AND SERUM, FOCUSING ON BIOMARKERS THAT CAN BE RELATED TO TREATMENT AND CLINICAL OUTCOMES.EXPERT OPINION: AN IDEAL BIOMARKER, OR A PANEL OF BIOMARKERS, COULD REVOLUTIONIZE THE WAY WE ADDRESS AND PROPOSE TREATMENTS FOR THIS DISEASE. ONCE SEVERE PRESENTATIONS AND PHENOTYPES HAVE BEEN IDENTIFIED USING A RELIABLE BIOMARKER, PATIENTS COULD BE TREATED AT EARLIER DISEASE STAGES WITH MORE SPECIFIC MEDICATIONS. THE MOST IMPORTANT BIOMARKERS WITH THE MOST SIGNIFICANT LEVELS OF EVIDENCE COMPRISED CALCITONIN GENE-RELATED PEPTIDE (CGRP), GLUTAMATE, NERVE GROWTH FACTOR, SOME INFLAMMATORY (CRP, TNF-ALPHA, INTERLEUKINS) AND OXIDATIVE STRESS MARKERS. CGRP WAS ASSOCIATED WITH EPISODIC, CHRONIC MIGRAINE AND RESPONSE TO TREATMENT. PITUITARY ADENYLATE CYCLASE-ACTIVATING POLYPEPTIDE IS AN EMERGING NEUROPEPTIDE INVOLVED IN MIGRAINE DIAGNOSTICS AND SEVERITY. NEW GENETIC AND EPIGENETIC BIOMARKERS WILL BE CANDIDATES FOR FUTURE RESEARCH. 2021 17 6524 35 TRANSCRIPTIONAL AND EPIGENETIC RESPONSE TO SEDENTARY BEHAVIOR AND PHYSICAL ACTIVITY IN CHILDREN AND ADOLESCENTS: A SYSTEMATIC REVIEW. BACKGROUND: THE LINKS OF SEDENTARY BEHAVIOR AND PHYSICAL ACTIVITY WITH HEALTH OUTCOMES IN CHILDREN AND ADOLESCENTS IS WELL KNOWN. HOWEVER, THE MOLECULAR MECHANISMS INVOLVED ARE POORLY UNDERSTOOD. WE AIMED TO SYNTHESIZE THE CURRENT KNOWLEDGE OF THE ASSOCIATION OF SEDENTARY BEHAVIOR AND PHYSICAL ACTIVITY (ACUTE AND CHRONIC EFFECTS) WITH GENE EXPRESSION AND EPIGENETIC MODIFICATIONS IN CHILDREN AND ADOLESCENTS. METHODS: PUBMED, WEB OF SCIENCE, AND SCOPUS DATABASES WERE SYSTEMATICALLY SEARCHED UNTIL APRIL 2022. A TOTAL OF 15 ARTICLES WERE ELIGIBLE FOR THIS REVIEW. THE RISK OF BIAS ASSESSMENT WAS PERFORMED USING THE JOANNA BRIGGS INSTITUTE CRITICAL APPRAISAL TOOL FOR SYSTEMATIC REVIEWS AND/OR A MODIFIED VERSION OF THE DOWNS AND BLACK CHECKLIST. RESULTS: THIRTEEN STUDIES USED CANDIDATE GENE APPROACH, WHILE ONLY 2 STUDIES PERFORMED HIGH-THROUGHPUT ANALYSES. THE CANDIDATE GENES SIGNIFICANTLY LINKED TO SEDENTARY BEHAVIOR OR PHYSICAL ACTIVITY WERE: FOXP3, HSD11B2, IL-10, TNF-ALPHA, ADRB2, VEGF, HSP70, SOX, AND GPX. NON-CODING RIBONUCLEIC ACIDS (RNAS) REGULATED BY SEDENTARY BEHAVIOR OR PHYSICAL ACTIVITY WERE: MIRNA-222, MIRNA-146(A), MIRNA-16, MIRNA-126, MIR-320(A), AND LONG NON-CODING RNA MALAT1. THESE MOLECULES ARE INVOLVED IN INFLAMMATION, IMMUNE FUNCTION, ANGIOGENIC PROCESS, AND CARDIOVASCULAR DISEASE. TRANSCRIPTOMICS ANALYSES DETECTED THOUSANDS OF GENES THAT WERE ALTERED FOLLOWING AN ACUTE BOUT OF PHYSICAL ACTIVITY AND ARE LINKED TO GENE PATHWAYS RELATED TO IMMUNE FUNCTION, APOPTOSIS, AND METABOLIC DISEASES. CONCLUSION: THE EVIDENCE FOUND TO DATE IS RATHER LIMITED. MULTIDISCIPLINARY STUDIES ARE ESSENTIAL TO CHARACTERIZE THE MOLECULAR MECHANISMS IN RESPONSE TO SEDENTARY BEHAVIOR AND PHYSICAL ACTIVITY IN THE PEDIATRIC POPULATION. LARGER COHORTS AND RANDOMIZED CONTROLLED TRIALS, IN COMBINATION WITH MULTI-OMICS ANALYSES, MAY PROVIDE THE NECESSARY DATA TO BRING THE FIELD FORWARD. SYSTEMATIC REVIEW REGISTRATION: [WWW.CLINICALTRIALS.GOV], IDENTIFIER [CRD42021235431]. 2022 18 344 30 ALTERED BDNF METHYLATION IN PATIENTS WITH CHRONIC MUSCULOSKELETAL PAIN AND HIGH BIOPSYCHOSOCIAL COMPLEXITY. PURPOSE: THE INTERMED INSTRUMENT, WHICH WAS DEVELOPED TO MEASURE PATIENT'S BIOPSYCHOSOCIAL (BPS) COMPLEXITY, REPRESENTS A POWERFUL DIAGNOSTIC AND THERAPEUTIC TOOL. EPIGENETIC CHANGES ARE THE INTERFACE BETWEEN SIGNALS FROM THE ENVIRONMENT AND GENETIC MODIFICATIONS, AFFECTING GENE EXPRESSION, IN PARTICULAR, BY DNA METHYLATION OF CPG DINUCLEOTIDES IN PROMOTOR REGIONS OF THE CORRESPONDING GENES. THE BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) GENE PLAYS A CRUCIAL ROLE IN THE CENTRAL SENSITIZATION (CS) OF PAIN. IN THIS STUDY, WE HYPOTHESIZED THAT CHRONIC PAIN MODIFIES THE METHYLATION LEVELS OF THE BDNF GENE IN A MANNER THAT IS INTERCONNECTED WITH THE BPS STATUS. PATIENTS AND METHODS: FIFTY-EIGHT CHRONIC MUSCULOSKELETAL PAIN PATIENTS (CMSP) WERE ENROLLED IN THE STUDY. DNA WAS EXTRACTED FROM BLOOD SAMPLES, THE METHYLATION LEVELS OF 13 CPG SITES IN THE BDNF PROMOTER WERE MEASURED BY PYROSEQUENCING, AND ASSOCIATION STUDIES WITH VARIOUS PATIENT PARAMETERS AND THE INTERMED SCORES WERE PERFORMED. RESULTS: INTERESTINGLY, A NEGATIVE CORRELATION (-0.40) WAS FOUND BETWEEN THE TOTAL INTERMED SCORES AND THE AVERAGE CPG METHYLATION VALUES OF THE BDNF GENE, BUT NO CORRELATION WAS OBSERVED WITH THE SEVERITY OF PAIN, DEGREE OF ANXIETY, DEPRESSION, OR KINESIOPHOBIA AND CATASTROPHISM. MOREOVER, THE ASSOCIATION WAS INDEPENDENT OF AGE, SEX AND LEVEL OF COMORBIDITIES. CONCLUSION: THIS RESULT SHOWS THAT CMSP, IN ASSOCIATION WITH ITS BIOPSYCHOSOCIAL CONTEXT, EPIGENETICALLY DECREASES THE DEGREE OF METHYLATION OF THE BDNF PROMOTER AND SHOULD THEREFORE INCREASE THE LEVEL OF BDNF TRANSCRIPTION. IT ALSO SUGGESTS A ROLE OF THE INTERMED TOOL TO DETECT A RELATIONSHIP BETWEEN THE BPS COMPLEXITY AND THE EPIGENETIC CONTROL OF A TARGET GENE. THE POSSIBLE UPREGULATION OF BDNF EXPRESSION MIGHT BE, AT LEAST IN PART, THE SIGNAL FOR CHRONIC PAIN-INDUCED CENTRAL SENSITIZATION (CS). THIS COULD PARTLY EXPLAIN WHY PATIENTS WITH A HIGHER LEVEL OF COMPLEXITY FEEL MORE PAIN THAN THOSE WITH LOWER COMPLEXITY. 2020 19 3652 27 INDIVIDUAL DNA METHYLATION PATTERN SHIFTS IN NANOPARTICLES-EXPOSED WORKERS ANALYZED IN FOUR CONSECUTIVE YEARS. A DNA METHYLATION PATTERN REPRESENTS AN ORIGINAL PLAN OF THE FUNCTION SETTINGS OF INDIVIDUAL CELLS AND TISSUES. THE BASIC STRATEGIES OF ITS DEVELOPMENT AND CHANGES DURING THE HUMAN LIFETIME ARE KNOWN, BUT THE DETAILS RELATED TO ITS MODIFICATION OVER THE YEARS ON AN INDIVIDUAL BASIS HAVE NOT YET BEEN STUDIED. MOREOVER, CURRENT EVIDENCE SHOWS THAT ENVIRONMENTAL EXPOSURE COULD GENERATE CHANGES IN DNA METHYLATION SETTINGS AND, SUBSEQUENTLY, THE FUNCTION OF GENES. IN THIS STUDY, WE ANALYZED THE EFFECT OF CHRONIC EXPOSURE TO NANOPARTICLES (NP) IN OCCUPATIONALLY EXPOSED WORKERS REPEATEDLY SAMPLED IN FOUR CONSECUTIVE YEARS (2016-2019). A DETAILED METHYLATION PATTERN ANALYSIS OF 14 PERSONS (10 EXPOSED AND 4 CONTROLS) WAS PERFORMED ON AN INDIVIDUAL BASIS. A MICROARRAY-BASED APPROACH USING CHIPS, ALLOWING THE ASSESSMENT OF MORE THAN 850 K CPG LOCI, WAS USED. INDIVIDUAL DNA METHYLATION PATTERNS WERE COMPARED BY PRINCIPAL COMPONENT ANALYSIS (PCA). THE RESULTS SHOW THE SHIFT IN DNA METHYLATION PATTERNS IN INDIVIDUAL YEARS IN ALL THE EXPOSED AND CONTROL SUBJECTS. THE OVERALL RANGE OF DIFFERENCES VARIED BETWEEN THE YEARS IN INDIVIDUAL PERSONS. THE DIFFERENCES BETWEEN THE FIRST AND LAST YEAR OF EXAMINATION (A THREE-YEAR TIME PERIOD) SEEM TO BE CONSISTENTLY GREATER IN THE NP-EXPOSED SUBJECTS IN COMPARISON WITH THE CONTROLS. THE SELECTED 14 MOST DIFFERENTLY METHYLATED CG LOCI WERE RELATIVELY STABLE IN THE CHRONICALLY EXPOSED SUBJECTS. IN SUMMARY, THE SPECIFIC TYPE OF LONG-TERM EXPOSURE CAN CONTRIBUTE TO THE FIXING OF RELEVANT EPIGENETIC CHANGES RELATED TO A SPECIFIC ENVIRONMENT AS, E.G., NP INHALATION. 2021 20 3503 24 IDENTIFICATION OF POTENTIAL DIFFERENTIALLY METHYLATED GENE-RELATED BIOMARKERS IN ENDOMETRIOSIS. AIM: TO IDENTIFY EPIGENETIC ALTERATIONS OF DIFFERENTIALLY EXPRESSED GENES AND SCREEN OUT TARGETED THERAPEUTIC DRUGS IN ENDOMETRIOSIS. METHODS: BASED ON THE GENE EXPRESSION OMNIBUS DATABASE AND A SERIES OF BIOLOGICAL INFORMATION ANALYSIS TOOLS, SUPPLEMENTED BY VALIDATION OF CLINICAL SAMPLES, ABERRANT DNA METHYLATION-DRIVEN GENES AND THEIR FUNCTIONS WERE EXPLORED, AS WELL AS POSSIBLE TARGETED DRUGS. RESULTS: THIS STUDY SCREENED OUT A RANGE OF DNA METHYLATION-DRIVEN GENES THAT WERE ASSOCIATED WITH POWERFUL PROPERTIES AND CORRESPONDING PATHWAYS. AMONG THEM, BDNF AND CCL2 WERE KEY GENES IN THE DEVELOPMENT OF ENDOMETRIOSIS. FOUR CHEMICAL AGENTS HAVE BEEN FLAGGED AS POTENTIAL TREATMENTS FOR ENDOMETRIOSIS. CONCLUSION: THESE CANDIDATE GENES AND SMALL-MOLECULE AGENTS MAY BE FURTHER EXPLORED AS POTENTIAL TARGETS AND DRUGS FOR ENDOMETRIOSIS DIAGNOSIS AND THERAPY, RESPECTIVELY. 2022