1 2207 170 EPIGENETIC MODIFICATIONS AND GLUCOCORTICOID SENSITIVITY IN MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS). BACKGROUND: MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A DEBILITATING IDIOPATHIC DISEASE CHARACTERIZED BY UNEXPLAINED FATIGUE THAT FAILS TO RESOLVE WITH SUFFICIENT REST. DIAGNOSIS IS BASED ON A LIST OF SYMPTOMS AND EXCLUSION OF OTHER FATIGUE-RELATED HEALTH CONDITIONS. DESPITE A HETEROGENEOUS PATIENT POPULATION, IMMUNE AND HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS FUNCTION DIFFERENCES, SUCH AS ENHANCED NEGATIVE FEEDBACK TO GLUCOCORTICOIDS, ARE RECURRING FINDINGS IN ME/CFS STUDIES. EPIGENETIC MODIFICATIONS, SUCH AS CPG METHYLATION, ARE KNOWN TO REGULATE LONG-TERM PHENOTYPIC DIFFERENCES AND PREVIOUS WORK BY OUR GROUP FOUND DNA METHYLOME DIFFERENCES IN ME/CFS, HOWEVER THE RELATIONSHIP BETWEEN DNA METHYLOME MODIFICATIONS, CLINICAL AND FUNCTIONAL CHARACTERISTICS ASSOCIATED WITH ME/CFS HAS NOT BEEN EXAMINED. METHODS: WE EXAMINED THE DNA METHYLOME IN PERIPHERAL BLOOD MONONUCLEAR CELLS (PBMCS) OF A LARGER COHORT OF FEMALE ME/CFS PATIENTS USING THE ILLUMINA HUMANMETHYLATION450 BEADCHIP ARRAY. IN PARALLEL TO THE DNA METHYLOME ANALYSIS, WE INVESTIGATED IN VITRO GLUCOCORTICOID SENSITIVITY DIFFERENCES BY STIMULATING PBMCS WITH PHYTOHAEMAGGLUTININ AND SUPPRESSED GROWTH WITH DEXAMETHASONE. WE EXPLORED DNA METHYLATION DIFFERENCES USING BISULFITE PYROSEQUENCING AND STATISTICAL PERMUTATION. LINEAR REGRESSION WAS IMPLEMENTED TO DISCOVER EPIGENOMIC REGIONS ASSOCIATED WITH SELF-REPORTED QUALITY OF LIFE AND NETWORK ANALYSIS OF GENE ONTOLOGY TERMS TO BIOLOGICALLY CONTEXTUALIZE RESULTS. RESULTS: WE DETECTED 12,608 DIFFERENTIALLY METHYLATED SITES BETWEEN ME/CFS PATIENTS AND HEALTHY CONTROLS PREDOMINANTLY LOCALIZED TO CELLULAR METABOLISM GENES, SOME OF WHICH WERE ALSO RELATED TO SELF-REPORTED QUALITY OF LIFE HEALTH SCORES. AMONG ME/CFS PATIENTS, GLUCOCORTICOID SENSITIVITY WAS ASSOCIATED WITH DIFFERENTIAL METHYLATION AT 13 LOCI. CONCLUSIONS: OUR RESULTS INDICATE DNA METHYLATION MODIFICATIONS IN CELLULAR METABOLISM IN ME/CFS DESPITE A HETEROGENEOUS PATIENT POPULATION, IMPLICATING THESE PROCESSES IN IMMUNE AND HPA AXIS DYSFUNCTION IN ME/CFS. MODIFICATIONS TO EPIGENETIC LOCI ASSOCIATED WITH DIFFERENCES IN GLUCOCORTICOID SENSITIVITY MAY BE IMPORTANT AS BIOMARKERS FOR FUTURE CLINICAL TESTING. OVERALL, THESE FINDINGS ALIGN WITH RECENT ME/CFS WORK THAT POINT TOWARDS IMPAIRMENT IN CELLULAR ENERGY PRODUCTION IN THIS PATIENT POPULATION. 2017 2 107 35 A REVIEW OF PRE-CLINICAL MODELS FOR GULF WAR ILLNESS. GULF WAR ILLNESS (GWI) IS A CHRONIC MULTISYMPTOMATIC DISORDER THAT AFFLICTS OVER 1/3RD OF THE 1991 GW VETERANS. IT SPANS MULTIPLE BODILY SYSTEMS AND PRESENTS ITSELF AS A SYNDROME EXHIBITING DIVERSE SYMPTOMS INCLUDING FATIGUE, DEPRESSION, MOOD, AND MEMORY AND CONCENTRATION DEFICITS, MUSCULOSKELETAL PAIN AND GASTROINTESTINAL DISTRESS IN GW VETERANS. THE ETIOLOGY OF GWI IS COMPLEX AND MANY FACTORS, INCLUDING CHEMICAL, PHYSIOLOGICAL, AND ENVIRONMENTAL STRESSORS PRESENT IN THE GW ARENA, HAVE BEEN IMPLICATED FOR ITS DEVELOPMENT. IT HAS BEEN OVER 30 YEARS SINCE THE END OF THE GW BUT, GWI HAS BEEN PERSISTENT IN SUFFERING VETERANS WHO ARE ALSO DEALING WITH PAUCITY OF EFFECTIVE TREATMENTS. THE MULTIFACTORIAL ASPECT OF GWI ALONG WITH GENETIC HETEROGENEITY AND LACK OF AVAILABLE DATA SURROUNDING WAR-TIME EXPOSURES HAVE PROVED TO BE CHALLENGING IN DEVELOPING PRE-CLINICAL MODELS OF GWI. DESPITE THIS, OVER A DOZEN GWI ANIMAL MODELS EXIST IN THE LITERATURE. IN THIS ARTICLE, FOLLOWING A BRIEF DISCUSSION OF GW HISTORY, GWI DEFINITIONS, AND PROBABLE CAUSES FOR ITS PATHOGENESIS, WE WILL EXPAND UPON VARIOUS EXPERIMENTAL MODELS USED IN GWI LABORATORY RESEARCH. THESE ANIMAL MODELS WILL BE DISCUSSED IN THE CONTEXT OF THEIR ATTEMPTS AT MIMICKING GW-RELATED EXPOSURES WITH REGARDS TO THE VARIATIONS IN CHEMICAL COMBINATIONS, DOSES, AND FREQUENCY OF EXPOSURES. WE WILL DISCUSS THEIR ADVANTAGES AND LIMITATIONS IN MODELING GWI FOLLOWED BY A DISCUSSION OF BEHAVIORAL AND MOLECULAR FINDINGS IN THESE MODELS. THE MECHANISTIC DATA OBTAINED FROM THESE PRECLINICAL STUDIES HAVE OFFERED MULTIPLE MOLECULAR PATHWAYS INCLUDING CHRONIC INFLAMMATION, MITOCHONDRIAL DYSFUNCTION, OXIDATIVE STRESS, LIPID DISTURBANCES, CALCIUM HOMEOSTATIC ALTERATIONS, CHANGES IN GUT MICROBIOTA, AND EPIGENETIC MODIFICATIONS, AMONGST OTHERS FOR EXPLAINING GWI DEVELOPMENT AND ITS PERSISTENCE. FINALLY, THESE FINDINGS HAVE ALSO INFORMED US ON NOVEL DRUGGABLE TARGETS IN GWI. WHILE, IT HAS BEEN DIFFICULT TO CONCEIVE A SINGLE PRE-CLINICAL MODEL THAT COULD EXPRESS ALL THE GWI SIGNS AND EXHIBIT BIOLOGICAL COMPLEXITY REFLECTIVE OF THE CLINICAL PRESENTATION IN GWI, ANIMAL MODELS HAVE BEEN CRITICAL FOR IDENTIFYING MOLECULAR UNDERPINNINGS OF GWI AND EVALUATING TREATMENT STRATEGIES FOR GWI. 2021 3 351 52 ALTERED ENDOTHELIAL DYSFUNCTION-RELATED MIRS IN PLASMA FROM ME/CFS PATIENTS. MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A COMPLEX DISEASE CHARACTERIZED BY UNEXPLAINED DEBILITATING FATIGUE. ALTHOUGH THE ETIOLOGY IS UNKNOWN, EVIDENCE SUPPORTS IMMUNOLOGICAL ABNORMALITIES, SUCH AS PERSISTENT INFLAMMATION AND IMMUNE-CELL ACTIVATION, IN A SUBSET OF PATIENTS. SINCE THE INTERPLAY BETWEEN INFLAMMATION AND VASCULAR ALTERATIONS IS WELL-ESTABLISHED IN OTHER DISEASES, ENDOTHELIAL DYSFUNCTION HAS EMERGED AS ANOTHER PLAYER IN ME/CFS PATHOGENESIS. ENDOTHELIAL NITRIC OXIDE SYNTHASE (ENOS) GENERATES NITRIC OXIDE (NO) THAT MAINTAINS ENDOTHELIAL HOMEOSTASIS. ENOS IS ACTIVATED BY SILENT INFORMATION REGULATOR 1 (SIRT1), AN ANTI-INFLAMMATORY PROTEIN. DESPITE ITS RELEVANCE, NO STUDY HAS ADDRESSED THE SIRT1/ENOS AXIS IN ME/CFS. THE INTEREST IN CIRCULATING MICRORNAS (MIRS) AS POTENTIAL BIOMARKERS IN ME/CFS HAS INCREASED IN RECENT YEARS. ACCORDINGLY, WE ANALYZE A SET OF MIRS REPORTED TO MODULATE THE SIRT1/ENOS AXIS USING PLASMA FROM ME/CFS PATIENTS. OUR RESULTS SHOW THAT MIR-21, MIR-34A, MIR-92A, MIR-126, AND MIR-200C ARE JOINTLY INCREASED IN ME/CFS PATIENTS COMPARED TO HEALTHY CONTROLS. A SIMILAR FINDING WAS OBTAINED WHEN ANALYZING PUBLIC MIR DATA ON PERIPHERAL BLOOD MONONUCLEAR CELLS. BIOINFORMATICS ANALYSIS SHOWS THAT ENDOTHELIAL FUNCTION-RELATED SIGNALING PATHWAYS ARE ASSOCIATED WITH THESE MIRS, INCLUDING OXIDATIVE STRESS AND OXYGEN REGULATION. INTERESTINGLY, HISTONE DEACETYLASE 1, A PROTEIN RESPONSIBLE FOR EPIGENETIC REGULATIONS, REPRESENTED THE MOST RELEVANT NODE WITHIN THE NETWORK. IN CONCLUSION, OUR STUDY PROVIDES A BASIS TO FIND ENDOTHELIAL DYSFUNCTION-RELATED BIOMARKERS AND EXPLORE NOVEL TARGETS IN ME/CFS. 2021 4 3041 52 GENOME-EPIGENOME INTERACTIONS ASSOCIATED WITH MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME. MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A COMPLEX DISEASE OF UNKNOWN ETIOLOGY. MULTIPLE STUDIES POINT TO DISRUPTIONS IN IMMUNE FUNCTIONING IN ME/CFS PATIENTS AS WELL AS SPECIFIC GENETIC POLYMORPHISMS AND ALTERATIONS OF THE DNA METHYLOME IN LYMPHOCYTES. HOWEVER, POTENTIAL INTERACTIONS BETWEEN DNA METHYLATION AND GENETIC BACKGROUND IN RELATION TO ME/CFS HAVE NOT BEEN EXAMINED. IN THIS STUDY WE EXPLORED THIS ASSOCIATION BY CHARACTERIZING THE EPIGENETIC (~480 THOUSAND CPG LOCI) AND GENETIC (~4.3 MILLION SNPS) VARIATION BETWEEN COHORTS OF ME/CFS PATIENTS AND HEALTHY CONTROLS. WE FOUND SIGNIFICANT ASSOCIATIONS OF DNA METHYLATION STATES IN T-LYMPHOCYTES AT SEVERAL CPG LOCI AND REGIONS WITH ME/CFS PHENOTYPE. THESE METHYLATION ANOMALIES ARE IN CLOSE PROXIMITY TO GENES INVOLVED WITH IMMUNE FUNCTION AND CELLULAR METABOLISM. FINALLY, WE FOUND SIGNIFICANT CORRELATIONS OF GENOTYPES WITH METHYLATION MODIFICATIONS ASSOCIATED WITH ME/CFS. THE FINDINGS FROM THIS STUDY HIGHLIGHT THE ROLE OF EPIGENETIC AND GENETIC INTERACTIONS IN COMPLEX DISEASES, AND SUGGEST SEVERAL GENETIC AND EPIGENETIC ELEMENTS POTENTIALLY INVOLVED IN THE MECHANISMS OF DISEASE IN ME/CFS. 2018 5 6438 35 THERAPEUTIC AND PREVENTIVE INTERVENTIONS FOR POSTULATED VASOACTIVE NEUROPEPTIDE AUTOIMMUNE FATIGUE-RELATED DISORDERS. MAJOR ADVANCES HAVE BEEN MADE IN UNDERSTANDING THE RELATIVELY NOVEL GROUP OF VASOACTIVE (VASODILATORY) NEUROPEPTIDES (VNS) IN HUMANS. VNS COMPRISE A NOVEL BUT EXPANDING GROUP OF SUBSTANCES HAVING IMMUNOREGULATION, INFLAMMATION MODULATION, NEUROTRANSMITTER, NEUROTROPHIC, HORMONAL AND METABOLIC FUNCTIONS. THESE SUBSTANCES MAY CONTROL GENE EXPRESSION FOR MRNA FOR THEMSELVES AND THEIR RECEPTORS. THEY HAVE COMPLEX RELATIONSHIPS WITH GASEOUS AND OTHER NEUROTRANSMITTERS AND XENOBIOTIC SUBSTANCES. THEORETICAL ARGUMENTS HAVE IMPLICATED THESE SUBSTANCES IN AUTOIMMUNE PHENOMENA RESULTING IN FATIGUE-RELATED CONDITIONS SUCH AS CHRONIC FATIGUE SYNDROME (CFS), SUDDEN INFANT DEATH SYNDROME (SIDS), FIBROMYALGIA (FM) AND GULF WAR SYNDROME (GWS) BUT REMAIN UNPROVEN. AS WELL AS POSSIBLY SPONTANEOUS ONSET, THE PRECIPITATING CAUSES OF VN AUTOIMMUNE DYSFUNCTION ARE LIKELY TO BE A COMBINATION OF GENETIC PREDISPOSITION, INFECTION AND XENOBIOTIC SUBSTANCES. THERAPEUTIC AND PREVENTIVE POSSIBILITIES FOR POSTULATED VN AUTOIMMUNE CONDITIONS WILL BE INFLUENCED BY THE COMPLEX PATHOLOPHYSIOLOGY UNDERPINNING THEM. SOME SPECULATIVE POSSIBILITIES ARE VN SUBSTITUTION/REPLACEMENT, PRESERVATION OF BIOLOGICAL EFFECT, EPIGENETIC DNA MODIFICATIONS, PLASMA EXCHANGE, ANTI-CHOLINESTERASES, E.G., PYRIDOSTIGMINE, CORTICOSTEROIDS AND OTHER DRUG TREATMENTS, THYMECTOMY, INTRAVENOUS IMMUNOGLOBULIN AND ANTI-IDIOTYPE ANTIBODIES, AND CPG/DNA VACCINES. PREVENTION AND TREATMENT OF POSSIBLE VN AUTOIMMUNE FATIGUE-RELATED DISORDERS MAY PROVE TO BE IMPORTANT AREAS FOR FUTURE RESEARCH AND DEVELOPMENT. 2005 6 6406 40 THE SEARCH FOR RELIABLE BIOMARKERS OF DISEASE IN MULTIPLE CHEMICAL SENSITIVITY AND OTHER ENVIRONMENTAL INTOLERANCES. WHILST FACING A WORLDWIDE FAST INCREASE OF FOOD AND ENVIRONMENTAL ALLERGIES, THE MEDICAL COMMUNITY IS ALSO CONFRONTED WITH ANOTHER INHOMOGENEOUS GROUP OF ENVIRONMENT-ASSOCIATED DISABLING CONDITIONS, INCLUDING MULTIPLE CHEMICAL SENSITIVITY (MCS), FIBROMYALGIA, CHRONIC FATIGUE SYNDROME, ELECTRIC HYPERSENSITIVITY, AMALGAM DISEASE AND OTHERS. THESE SHARE THE FEATURES OF POLY-SYMPTOMATIC MULTI-ORGAN CUTANEOUS AND SYSTEMIC MANIFESTATIONS, WITH POSTULATED INHERITED/ACQUIRED IMPAIRED METABOLISM OF CHEMICAL/PHYSICAL/NUTRITIONAL XENOBIOTICS, TRIGGERING ADVERSE REACTIONS AT EXPOSURE LEVELS FAR BELOW TOXICOLOGICALLY-RELEVANT VALUES, OFTEN IN THE ABSENCE OF CLEAR-CUT ALLERGOLOGIC AND/OR IMMUNOLOGIC INVOLVEMENT. DUE TO THE LACK OF PROVEN PATHOGENIC MECHANISMS GENERATING MEASURABLE DISEASE BIOMARKERS, THESE ENVIRONMENTAL HYPERSENSITIVITIES ARE GENERALLY IGNORED BY SANITARY AND SOCIAL SYSTEMS, AS PSYCHOGENIC OR "MEDICALLY UNEXPLAINED SYMPTOMS". THE UNCONTROLLED APPLICATION OF DIAGNOSTIC AND TREATMENT PROTOCOLS NOT CORRESPONDING TO ACCEPTABLE LEVELS OF VALIDATION, SAFETY, AND CLINICAL EFFICACY, TO A STEADILY INCREASING NUMBER OF PATIENTS DEMANDING ASSISTANCE, OCCURS IN MANY COUNTRIES IN THE ABSENCE OF EVIDENCE-BASED GUIDELINES. HERE WE REVISE AVAILABLE INFORMATION SUPPORTING THE ORGANIC NATURE OF THESE CLINICAL CONDITIONS. FOLLOWING INTENSE RESEARCH ON GENE POLYMORPHISMS OF PHASE I/II DETOXIFICATION ENZYME GENES, SO FAR STATISTICALLY INCONCLUSIVE, EPIGENETIC AND METABOLIC FACTORS ARE UNDER INVESTIGATION, IN PARTICULAR FREE RADICAL/ANTIOXIDANT HOMEOSTASIS DISTURBANCES. THE FINDING OF RELEVANT ALTERATIONS OF CATALASE, GLUTATHIONE-TRANSFERASE AND PEROXIDASE DETOXIFYING ACTIVITIES SIGNIFICANTLY CORRELATING WITH CLINICAL MANIFESTATIONS OF MCS, HAS RECENTLY REGISTERED SOME PROGRESS TOWARDS THE IDENTIFICATION OF RELIABLE BIOMARKERS OF DISEASE ONSET, PROGRESSION, AND TREATMENT OUTCOMES. 2011 7 639 52 BIOMARKERS FOR MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS): A SYSTEMATIC REVIEW. BACKGROUND: MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A MULTIFACETED CONDITION THAT AFFECTS MOST BODY SYSTEMS. THERE IS CURRENTLY NO KNOWN DIAGNOSTIC BIOMARKER; INSTEAD, DIAGNOSIS IS DEPENDENT ON APPLICATION OF SYMPTOM-BASED CASE CRITERIA FOLLOWING EXCLUSION OF ANY OTHER POTENTIAL MEDICAL CONDITIONS. WHILE THERE ARE SOME STUDIES THAT REPORT POTENTIAL BIOMARKERS FOR ME/CFS, THEIR EFFICACY HAS NOT BEEN VALIDATED. THE AIM OF THIS SYSTEMATIC REVIEW IS TO COLLATE AND APPRAISE LITERATURE PERTAINING TO A POTENTIAL BIOMARKER(S) WHICH MAY EFFECTIVELY DIFFERENTIATE ME/CFS PATIENTS FROM HEALTHY CONTROLS. METHODS: THIS SYSTEMATIC REVIEW WAS CONDUCTED ACCORDING TO THE PREFERRED REPORTING ITEMS FOR SYSTEMATIC REVIEWS AND META-ANALYSES AND COCHRANE REVIEW GUIDELINES. PUBMED, EMBASE AND SCOPUS WERE SYSTEMATICALLY SEARCHED FOR ARTICLES CONTAINING "BIOMARKER" AND "ME/CFS" KEYWORDS IN THE ABSTRACT OR TITLE AND IF THEY INCLUDED THE FOLLOWING CRITERIA: (1) WERE OBSERVATIONAL STUDIES PUBLISHED BETWEEN DECEMBER 1994 AND APRIL 2022; (2) INVOLVED ADULT HUMAN PARTICIPANTS; (3) FULL TEXT IS AVAILABLE IN ENGLISH (4) ORIGINAL RESEARCH; (5) DIAGNOSIS OF ME/CFS PATIENTS MADE ACCORDING TO THE FUKUDA CRITERIA (1994), CANADIAN CONSENSUS CRITERIA (2003), INTERNATIONAL CONSENSUS CRITERIA (2011) OR INSTITUTE OF MEDICINE CRITERIA (2015); (6) STUDY INVESTIGATED POTENTIAL BIOMARKERS OF ME/CFS COMPARED TO HEALTHY CONTROLS. QUALITY AND BIAS WERE ASSESSED USING THE JOANNA BRIGGS INSTITUTE CRITICAL APPRAISAL CHECKLIST FOR CASE CONTROL STUDIES. RESULTS: A TOTAL OF 101 PUBLICATIONS WERE INCLUDED IN THIS SYSTEMATIC REVIEW. POTENTIAL BIOMARKERS RANGED FROM GENETIC/EPIGENETIC (19.8%), IMMUNOLOGICAL (29.7%), METABOLOMICS/MITOCHONDRIAL/MICROBIOME (14.85%), ENDOVASCULAR/CIRCULATORY (17.82%), NEUROLOGICAL (7.92%), ION CHANNEL (8.91%) AND PHYSICAL DYSFUNCTION BIOMARKERS (8.91%). MOST OF THE POTENTIAL BIOMARKERS REPORTED WERE BLOOD-BASED (79.2%). USE OF LYMPHOCYTES AS A MODEL TO INVESTIGATE ME/CFS PATHOLOGY WAS PROMINENT AMONG IMMUNE-BASED BIOMARKERS. MOST BIOMARKERS HAD SECONDARY (43.56%) OR TERTIARY (54.47%) SELECTIVITY, WHICH IS THE ABILITY FOR THE BIOMARKER TO IDENTIFY A DISEASE-CAUSING AGENT, AND A MODERATE (59.40%) TO COMPLEX (39.60%) EASE-OF-DETECTION, INCLUDING THE REQUIREMENT OF SPECIALISED EQUIPMENT. CONCLUSIONS: ALL POTENTIAL ME/CFS BIOMARKERS DIFFERED IN EFFICIENCY, QUALITY, AND TRANSLATABILITY AS A DIAGNOSTIC MARKER. REPRODUCIBILITY OF FINDINGS BETWEEN THE INCLUDED PUBLICATIONS WERE LIMITED, HOWEVER, SEVERAL STUDIES VALIDATED THE INVOLVEMENT OF IMMUNE DYSFUNCTION IN THE PATHOLOGY OF ME/CFS AND THE USE OF LYMPHOCYTES AS A MODEL TO INVESTIGATE THE PATHOMECHANISM OF ILLNESS. THE HETEROGENEITY SHOWN ACROSS MANY OF THE INCLUDED STUDIES HIGHLIGHTS THE NEED FOR MULTIDISCIPLINARY RESEARCH AND UNIFORM PROTOCOLS IN ME/CFS BIOMARKER RESEARCH. 2023 8 1026 39 CIRCULATING MIRNAS EXPRESSION IN MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME. MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A COMPLEX MULTIFACTORIAL DISEASE THAT CAUSES INCREASING MORBIDITY WORLDWIDE, AND MANY INDIVIDUALS WITH ME/CFS SYMPTOMS REMAIN UNDIAGNOSED DUE TO THE LACK OF DIAGNOSTIC BIOMARKERS. ITS ETIOLOGY IS STILL UNKNOWN, BUT INCREASING EVIDENCE SUPPORTS A ROLE OF HERPESVIRUSES (INCLUDING HHV-6A AND HHV-6B) AS POTENTIAL TRIGGERS. INTERESTINGLY, THE INFECTION BY THESE VIRUSES HAS BEEN REPORTED TO IMPACT THE EXPRESSION OF MICRORNAS (MIRNAS), SHORT NON-CODING RNA SEQUENCES WHICH HAVE BEEN SUGGESTED TO BE EPIGENETIC FACTORS MODULATING ME/CFS PATHOGENIC MECHANISMS. NOTABLY, THE PRESENCE OF CIRCULATING MIRNAS IN PLASMA HAS RAISED THE POSSIBILITY TO USE THEM AS VALUABLE BIOMARKERS FOR DISTINGUISHING ME/CFS PATIENTS FROM HEALTHY CONTROLS. THUS, THIS STUDY AIMED AT DETERMINING THE ROLE OF EIGHT MIRNAS, WHICH WERE SELECTED FOR THEIR PREVIOUS ASSOCIATION WITH ME/CFS, AS POTENTIAL CIRCULATING BIOMARKERS OF THE DISEASE. THEIR PRESENCE WAS QUANTITATIVELY EVALUATED IN PLASMA FROM 40 ME/CFS PATIENTS AND 20 HEALTHY CONTROLS BY SPECIFIC TAQMAN ASSAYS, AND THE RESULTS SHOWED THAT SIX OUT OF THE EIGHT OF THE SELECTED MIRNAS WERE DIFFERENTLY EXPRESSED IN PATIENTS COMPARED TO CONTROLS; MORE SPECIFICALLY, FIVE MIRNAS WERE SIGNIFICANTLY UPREGULATED (MIR-127-3P, MIR-142-5P, MIR-143-3P, MIR-150-5P, AND MIR-448), AND ONE WAS DOWNMODULATED (MIR-140-5P). MIRNA LEVELS DIRECTLY CORRELATED WITH DISEASE SEVERITY, WHEREAS NO SIGNIFICANT CORRELATIONS WERE OBSERVED WITH THE PLASMA LEVELS OF SEVEN PRO-INFLAMMATORY CYTOKINES OR WITH THE PRESENCE/LOAD OF HHV-6A/6B GENOME, AS JUDGED BY SPECIFIC PCR AMPLIFICATION. THE RESULTS MAY OPEN THE WAY FOR FURTHER VALIDATION OF MIRNAS AS NEW POTENTIAL BIOMARKERS IN ME/CFS AND INCREASE THE KNOWLEDGE OF THE COMPLEX PATHWAYS INVOLVED IN THE ME/CFS DEVELOPMENT. 2023 9 5451 32 REPROGRAMMING CELLS FROM GULF WAR VETERANS INTO NEURONS TO STUDY GULF WAR ILLNESS. GULF WAR ILLNESS (GWI), WHICH AFFLICTS AT LEAST 25% OF VETERANS WHO SERVED IN THE 1990-1991 WAR IN THE PERSIAN GULF, IS THOUGHT TO BE CAUSED BY DEPLOYMENT EXPOSURES TO VARIOUS NEUROTOXICANTS, INCLUDING PESTICIDES, ANTI-NERVE GAS PILLS, AND LOW-LEVEL NERVE AGENTS INCLUDING SARIN/CYCLOSARIN. GWI IS A MULTISYMPTOM DISORDER CHARACTERIZED BY FATIGUE, JOINT PAIN, COGNITIVE PROBLEMS, AND GASTROINTESTINAL COMPLAINTS. THE MOST PROMINENT SYMPTOMS OF GWI (MEMORY PROBLEMS, POOR ATTENTION/CONCENTRATION, CHRONIC HEADACHES, MOOD ALTERATIONS, AND IMPAIRED SLEEP) SUGGEST THAT THE DISEASE PRIMARILY AFFECTS THE CNS. DEVELOPMENT OF URGENTLY NEEDED TREATMENTS DEPENDS ON EXPERIMENTAL MODELS APPROPRIATE FOR TESTING MECHANISTIC HYPOTHESES AND FOR SCREENING THERAPEUTIC COMPOUNDS. RODENT MODELS HAVE BEEN USEFUL THUS FAR, BUT ARE LIMITED BY THEIR INABILITY TO ASSESS THE CONTRIBUTION OF GENETIC OR EPIGENETIC BACKGROUND TO THE DISEASE, AND BECAUSE DISEASE-VULNERABLE PROTEINS AND PATHWAYS MAY BE DIFFERENT IN HUMANS RELATIVE TO RODENTS. AS OF YET, NO POSTMORTEM TISSUE FROM THE VETERANS HAS BECOME AVAILABLE FOR RESEARCH. WE ARE MOVING FORWARD WITH A PARADIGM SHIFT IN THE STUDY OF GWI, WHICH UTILIZES CONTEMPORARY STEM CELL TECHNOLOGY TO CONVERT SOMATIC CELLS FROM GULF WAR VETERANS INTO PLURIPOTENT CELL LINES THAT CAN BE DIFFERENTIATED INTO VARIOUS CELL TYPES, INCLUDING NEURONS, GLIA, MUSCLE, OR OTHER RELEVANT CELL TYPES. SUCH CELL LINES ARE IMMORTAL AND WILL BE A RESOURCE FOR GWI RESEARCHERS TO PURSUE MECHANISTIC HYPOTHESES AND THERAPEUTICS. 2017 10 41 36 A COMPARISON OF NEUROIMAGING ABNORMALITIES IN MULTIPLE SCLEROSIS, MAJOR DEPRESSION AND CHRONIC FATIGUE SYNDROME (MYALGIC ENCEPHALOMYELITIS): IS THERE A COMMON CAUSE? THERE IS COPIOUS EVIDENCE OF ABNORMALITIES IN RESTING-STATE FUNCTIONAL NETWORK CONNECTIVITY STATES, GREY AND WHITE MATTER PATHOLOGY AND IMPAIRED CEREBRAL PERFUSION IN PATIENTS AFFORDED A DIAGNOSIS OF MULTIPLE SCLEROSIS, MAJOR DEPRESSION OR CHRONIC FATIGUE SYNDROME (CFS) (MYALGIC ENCEPHALOMYELITIS). SYSTEMIC INFLAMMATION MAY WELL BE A MAJOR ELEMENT EXPLAINING SUCH FINDINGS. INTER-PATIENT AND INTER-ILLNESS VARIATIONS IN NEUROIMAGING FINDINGS MAY ARISE AT LEAST IN PART FROM REGIONAL GENETIC, EPIGENETIC AND ENVIRONMENTAL VARIATIONS IN THE FUNCTIONS OF MICROGLIA AND ASTROCYTES. REGIONAL DIFFERENCES IN NEURONAL RESISTANCE TO OXIDATIVE AND INFLAMMATORY INSULTS AND IN THE PERFORMANCE OF ANTIOXIDANT DEFENCES IN THE CENTRAL NERVOUS SYSTEM MAY ALSO PLAY A ROLE. IMPORTANTLY, REPLICATED EXPERIMENTAL FINDINGS SUGGEST THAT THE USE OF HIGH-RESOLUTION SPECT IMAGING MAY HAVE THE CAPACITY TO DIFFERENTIATE PATIENTS AFFORDED A DIAGNOSIS OF CFS FROM THOSE WITH A DIAGNOSIS OF DEPRESSION. FURTHER RESEARCH INVOLVING THIS FORM OF NEUROIMAGING APPEARS WARRANTED IN AN ATTEMPT TO OVERCOME THE PROBLEM OF AETIOLOGICALLY HETEROGENEOUS COHORTS WHICH PROBABLY EXPLAIN CONFLICTING FINDINGS PRODUCED BY INVESTIGATIVE TEAMS ACTIVE IN THIS FIELD. HOWEVER, THE IONISING RADIATION AND RELATIVE LACK OF SENSITIVITY INVOLVED PROBABLY PRECLUDE ITS USE AS A ROUTINE DIAGNOSTIC TOOL. 2018 11 3496 70 IDENTIFICATION OF MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME-ASSOCIATED DNA METHYLATION PATTERNS. BACKGROUND: MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A COMPLEX CONDITION INVOLVING MULTIPLE ORGAN SYSTEMS AND CHARACTERIZED BY PERSISTENT/RELAPSING DEBILITATING FATIGUE, IMMUNE DYSFUNCTION, NEUROLOGICAL PROBLEMS, AND OTHER SYMPTOMS NOT CURABLE FOR AT LEAST 6 MONTHS. DISRUPTION OF DNA METHYLATION PATTERNS HAS BEEN TIED TO VARIOUS IMMUNE AND NEUROLOGICAL DISEASES; HOWEVER, ITS STATUS IN ME/CFS REMAINS UNCERTAIN. OUR STUDY AIMED AT IDENTIFYING CHANGES IN THE DNA METHYLATION PATTERNS THAT ASSOCIATE WITH ME/CFS. METHODS: WE EXTRACTED GENOMIC DNA FROM PERIPHERAL BLOOD MONONUCLEAR CELLS FROM 13 ME/CFS STUDY SUBJECTS AND 12 HEALTHY CONTROLS AND MEASURED GLOBAL DNA METHYLATION BY ELISA-LIKE METHOD AND SITE-SPECIFIC METHYLATION STATUS USING ILLUMINA METHYLATIONEPIC MICROARRAYS. PYROSEQUENCING VALIDATION INCLUDED 33 ME/CFS CASES AND 31 CONTROLS FROM TWO GEOGRAPHICALLY DISTANT COHORTS. RESULTS: GLOBAL DNA METHYLATION LEVELS OF ME/CFS CASES WERE SIMILAR TO THOSE OF CONTROLS. HOWEVER, MICROARRAY-BASED APPROACH ALLOWED DETECTION OF 17,296 DIFFERENTIALLY METHYLATED CPG SITES IN 6,368 GENES ACROSS REGULATORY ELEMENTS AND WITHIN CODING REGIONS OF GENES. ANALYSIS OF DNA METHYLATION IN PROMOTER REGIONS REVEALED 307 DIFFERENTIALLY METHYLATED PROMOTERS. INGENUITY PATHWAY ANALYSIS INDICATED THAT GENES ASSOCIATED WITH DIFFERENTIALLY METHYLATED PROMOTERS PARTICIPATED IN AT LEAST 15 DIFFERENT PATHWAYS MOSTLY RELATED TO CELL SIGNALING WITH A STRONG IMMUNE COMPONENT. CONCLUSIONS: THIS IS THE FIRST STUDY THAT HAS EXPLORED GENOME-WIDE EPIGENETIC CHANGES ASSOCIATED WITH ME/CFS USING THE ADVANCED ILLUMINA METHYLATIONEPIC MICROARRAYS COVERING ABOUT 850,000 CPG SITES IN TWO GEOGRAPHICALLY DISTANT COHORTS OF ME/CFS CASES AND MATCHED CONTROLS. OUR RESULTS ARE ALIGNED WITH PREVIOUS STUDIES THAT INDICATE A DYSREGULATION OF THE IMMUNE SYSTEM IN ME/CFS. THEY ALSO SUGGEST A POTENTIAL ROLE OF EPIGENETIC DE-REGULATION IN THE PATHOBIOLOGY OF ME/CFS. WE PROPOSE SCREENING OF LARGER COHORTS OF ME/CFS CASES TO DETERMINE THE EXTERNAL VALIDITY OF THESE EPIGENETIC CHANGES IN ORDER TO IMPLEMENT THEM AS POSSIBLE DIAGNOSTIC MARKERS IN CLINICAL SETTING. 2018 12 1556 74 DNA METHYLATION MODIFICATIONS ASSOCIATED WITH CHRONIC FATIGUE SYNDROME. CHRONIC FATIGUE SYNDROME (CFS), ALSO KNOWN AS MYALGIC ENCEPHALOMYELITIS, IS A COMPLEX MULTIFACTORIAL DISEASE THAT IS CHARACTERIZED BY THE PERSISTENT PRESENCE OF FATIGUE AND OTHER PARTICULAR SYMPTOMS FOR A MINIMUM OF 6 MONTHS. SYMPTOMS FAIL TO DISSIPATE AFTER SUFFICIENT REST AND HAVE MAJOR EFFECTS ON THE DAILY FUNCTIONING OF CFS SUFFERERS. CFS IS A MULTI-SYSTEM DISEASE WITH A HETEROGENEOUS PATIENT POPULATION SHOWING A WIDE VARIETY OF FUNCTIONAL DISABILITIES AND ITS BIOLOGICAL BASIS REMAINS POORLY UNDERSTOOD. STABLE ALTERATIONS IN GENE FUNCTION IN THE IMMUNE SYSTEM HAVE BEEN REPORTED IN SEVERAL STUDIES OF CFS. EPIGENETIC MODIFICATIONS HAVE BEEN IMPLICATED IN LONG-TERM EFFECTS ON GENE FUNCTION, HOWEVER, TO OUR KNOWLEDGE, GENOME-WIDE EPIGENETIC MODIFICATIONS ASSOCIATED WITH CFS HAVE NOT BEEN EXPLORED. WE EXAMINED THE DNA METHYLOME IN PERIPHERAL BLOOD MONONUCLEAR CELLS ISOLATED FROM CFS PATIENTS AND HEALTHY CONTROLS USING THE ILLUMINA HUMANMETHYLATION450 BEADCHIP ARRAY, CONTROLLING FOR INVARIANT PROBES AND PROBES OVERLAPPING POLYMORPHIC SEQUENCES. GENE ONTOLOGY (GO) AND NETWORK ANALYSIS OF DIFFERENTIALLY METHYLATED GENES WAS PERFORMED TO DETERMINE POTENTIAL BIOLOGICAL PATHWAYS SHOWING CHANGES IN DNA METHYLATION IN CFS. WE FOUND AN INCREASED ABUNDANCE OF DIFFERENTIALLY METHYLATED GENES RELATED TO THE IMMUNE RESPONSE, CELLULAR METABOLISM, AND KINASE ACTIVITY. GENES ASSOCIATED WITH IMMUNE CELL REGULATION, THE LARGEST COORDINATED ENRICHMENT OF DIFFERENTIALLY METHYLATED PATHWAYS, SHOWED HYPOMETHYLATION WITHIN PROMOTERS AND OTHER GENE REGULATORY ELEMENTS IN CFS. THESE DATA ARE CONSISTENT WITH EVIDENCE OF MULTISYSTEM DYSREGULATION IN CFS AND IMPLICATE THE INVOLVEMENT OF DNA MODIFICATIONS IN CFS PATHOLOGY. 2014 13 1699 52 DYNAMIC EPIGENETIC CHANGES DURING A RELAPSE AND RECOVERY CYCLE IN MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME. MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A COMPLEX DISEASE WITH VARIABLE SEVERITY. PATIENTS EXPERIENCE FREQUENT RELAPSES WHERE SYMPTOMS INCREASE IN SEVERITY, LEAVING THEM WITH A MARKED REDUCTION IN QUALITY OF LIFE. PREVIOUS WORK HAS INVESTIGATED MOLECULAR DIFFERENCES BETWEEN ME/CFS PATIENTS AND HEALTHY CONTROLS, BUT NOT THE DYNAMIC CHANGES SPECIFIC TO EACH INDIVIDUAL PATIENT. WE APPLIED PRECISION MEDICINE HERE TO MAP GENOMIC CHANGES IN TWO SELECTED ME/CFS PATIENTS THROUGH A PERIOD THAT CONTAINED A RELAPSE RECOVERY CYCLE. DNA WAS ISOLATED FROM TWO PATIENTS AND A HEALTHY AGE/GENDER MATCHED CONTROL AT REGULAR INTERVALS AND CAPTURED THE PATIENT RELAPSE IN EACH CASE. REDUCED REPRESENTATION DNA METHYLATION SEQUENCING PROFILES WERE OBTAINED SPANNING THE RELAPSE RECOVERY CYCLE. BOTH PATIENTS SHOWED A SIGNIFICANTLY LARGER METHYLOME VARIABILITY (10-20-FOLD) THROUGH THE PERIOD OF SAMPLING COMPARED WITH THE CONTROL. DURING THE RELAPSE, CHANGES IN THE METHYLOME PROFILES OF THE TWO PATIENTS WERE DETECTED IN REGULATORY-ACTIVE REGIONS OF THE GENOME THAT WERE ASSOCIATED, RESPECTIVELY, WITH 157 AND 127 DOWNSTREAM GENES, INDICATING DISTURBED METABOLIC, IMMUNE AND INFLAMMATORY FUNCTIONS. SEVERE HEALTH RELAPSES IN THE ME/CFS PATIENTS RESULTED IN FUNCTIONALLY IMPORTANT CHANGES IN THEIR DNA METHYLOMES THAT, WHILE DIFFERING BETWEEN THE TWO PATIENTS, LED TO VERY SIMILAR COMPROMISED PHYSIOLOGY. DNA METHYLATION AS A SIGNATURE OF DISEASE VARIABILITY IN ONGOING ME/CFS MAY HAVE PRACTICAL APPLICATIONS FOR STRATEGIES TO DECREASE RELAPSE FREQUENCY. 2022 14 6375 43 THE ROLE OF NEURO-IMMUNE INTERACTION IN CHRONIC PAIN CONDITIONS; FUNCTIONAL SOMATIC SYNDROME, NEUROGENIC INFLAMMATION, AND PERIPHERAL NEUROPATHY. FUNCTIONAL SOMATIC SYNDROMES ARE INCREASINGLY DIAGNOSED IN CHRONICALLY ILL PATIENTS PRESENTING WITH AN ARRAY OF SYMPTOMS NOT ATTRIBUTED TO PHYSICAL AILMENTS. CONDITIONS SUCH AS CHRONIC FATIGUE SYNDROME, FIBROMYALGIA SYNDROME, OR IRRITABLE BOWEL SYNDROME ARE COMMON DISORDERS THAT BELONG IN THIS BROAD CATEGORY. SUCH SYNDROMES ARE CHARACTERISED BY THE PRESENCE OF ONE OR MULTIPLE CHRONIC SYMPTOMS INCLUDING WIDESPREAD MUSCULOSKELETAL PAIN, FATIGUE, SLEEP DISORDERS, AND ABDOMINAL PAIN, AMONGST OTHER ISSUES. SYMPTOMS ARE BELIEVED TO RELATE TO A COMPLEX INTERACTION OF BIOLOGICAL AND PSYCHOSOCIAL FACTORS, WHERE A DEFINITE AETIOLOGY HAS NOT BEEN ESTABLISHED. THEORIES SUGGEST CAUSATIVE PATHWAYS BETWEEN THE IMMUNE AND NERVOUS SYSTEMS OF AFFECTED INDIVIDUALS WITH SEVERAL RISK FACTORS IDENTIFIED IN PATIENTS PRESENTING WITH ONE OR MORE FUNCTIONAL SYNDROMES. RISK FACTORS INCLUDING STRESS AND CHILDHOOD TRAUMA ARE NOW RECOGNISED AS IMPORTANT CONTRIBUTORS TO CHRONIC PAIN CONDITIONS. EMOTIONAL, PHYSICAL, AND SEXUAL ABUSE DURING CHILDHOOD IS CONSIDERED A SEVERE STRESSOR HAVING A HIGH PREVALENCE IN FUNCTIONAL SOMATIC SYNDROME SUFFERS. SUCH TRAUMA PERMANENTLY ALTERS THE BIOLOGICAL STRESS RESPONSE OF THE SUFFERS LEADING TO NEUROEXCITATORY AND OTHER NERVE ISSUES ASSOCIATED WITH CHRONIC PAIN IN ADULTS. TRAUMATIC AND CHRONIC STRESS RESULTS IN EPIGENETIC CHANGES IN STRESS RESPONSE GENES, WHICH ULTIMATELY LEADS TO DYSREGULATION OF THE HYPOTHALAMIC-PITUITARY AXIS, THE AUTONOMIC NERVOUS SYSTEM, AND THE IMMUNE SYSTEM MANIFESTING IN A BROAD ARRAY OF SYMPTOMS. IMPORTANTLY, THESE SYSTEMS ARE KNOWN TO BE DYSREGULATED IN PATIENTS SUFFERING FROM FUNCTIONAL SOMATIC SYNDROME. FUNCTIONAL SOMATIC SYNDROMES ARE ALSO HIGHLY PREVALENT CO-MORBIDITIES OF PSYCHIATRIC CONDITIONS, MOOD DISORDERS, AND ANXIETY. CONSEQUENTLY, THIS REVIEW AIMS TO PROVIDE INSIGHT INTO THE ROLE OF THE NERVOUS SYSTEM AND IMMUNE SYSTEM IN CHRONIC PAIN DISORDERS ASSOCIATED WITH THE MUSCULOSKELETAL SYSTEM, AND CENTRAL AND PERIPHERAL NERVOUS SYSTEMS. 2022 15 2050 42 EPIGENETIC COMPONENTS OF MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME UNCOVER POTENTIAL TRANSPOSABLE ELEMENT ACTIVATION. PURPOSE: STUDIES TO DETERMINE EPIGENETIC CHANGES ASSOCIATED WITH MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) REMAIN SCARCE; HOWEVER, CURRENT EVIDENCE CLEARLY SHOWS THAT METHYLATION PATTERNS OF GENOMIC DNA AND NONCODING RNA PROFILES OF IMMUNE CELLS DIFFER BETWEEN PATIENTS AND HEALTHY SUBJECTS, SUGGESTING AN ACTIVE ROLE OF THESE EPIGENETIC MECHANISMS IN THE DISEASE. THE PRESENT STUDY COMPARES AND CONTRASTS THE AVAILABLE ME/CFS EPIGENETIC DATA IN AN EFFORT TO EVIDENCE OVERLAPPING PATHWAYS CAPABLE OF EXPLAINING AT LEAST SOME OF THE DYSFUNCTIONAL IMMUNE PARAMETERS LINKED TO THIS DISEASE. METHODS: A SYSTEMATIC SEARCH OF THE LITERATURE EVALUATING THE ME/CFS EPIGENOME LANDSCAPE WAS PERFORMED FOLLOWING THE PREFERRED REPORTING ITEMS FOR SYSTEMATIC REVIEWS AND META-ANALYSES CRITERIA. DIFFERENTIAL DNA METHYLATION AND NONCODING RNA DIFFERENTIAL EXPRESSION PATTERNS ASSOCIATED WITH ME/CFS WERE USED TO SCREEN FOR THE PRESENCE OF TRANSPOSABLE ELEMENTS USING THE DFAM BROWSER, A SEARCH PROGRAM NURTURED WITH THE REPBASE REPETITIVE SEQUENCE DATABASE AND THE REPEATMASKER ANNOTATION TOOL. FINDINGS: UNEXPECTEDLY, PARTICULAR ASSOCIATIONS OF TRANSPOSABLE ELEMENTS AND ME/CFS EPIGENETIC HALLMARKS WERE UNCOVERED. A MODEL FOR THE DISEASE EMERGED INVOLVING TRANSCRIPTIONAL INDUCTION OF ENDOGENOUS DORMANT TRANSPOSONS AND STRUCTURED CELLULAR RNA INTERACTIONS, TRIGGERING THE ACTIVATION OF THE INNATE IMMUNE SYSTEM WITHOUT A CONCOMITANT ACTIVE INFECTION. IMPLICATIONS: REPETITIVE SEQUENCE FILTERS (IE, REPEATMASKER) SHOULD BE AVOIDED WHEN ANALYZING TRANSCRIPTOMIC DATA TO ASSESS THE POTENTIAL PARTICIPATION OF REPETITIVE SEQUENCES ("JUNK REPETITIVE DNA"), REPRESENTING >45% OF THE HUMAN GENOME, IN THE ONSET AND EVOLUTION OF ME/CFS. IN ADDITION, TRANSPOSABLE ELEMENT SCREENINGS AIMED AT DESIGNING COST-EFFECTIVE, FOCUSED EMPIRICAL ASSAYS THAT CAN CONFIRM OR DISPROVE THE SUSPECTED INVOLVEMENT OF TRANSPOSON TRANSCRIPTIONAL ACTIVATION IN THIS DISEASE, FOLLOWING THE PILOT STRATEGY PRESENTED HERE, WILL REQUIRE DATABASES GATHERING LARGE ME/CFS EPIGENETIC DATASETS. 2019 16 6159 47 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 17 2816 43 FIBROMYALGIA: PATHOGENESIS, MECHANISMS, DIAGNOSIS AND TREATMENT OPTIONS UPDATE. FIBROMYALGIA IS A SYNDROME CHARACTERIZED BY CHRONIC AND WIDESPREAD MUSCULOSKELETAL PAIN, OFTEN ACCOMPANIED BY OTHER SYMPTOMS, SUCH AS FATIGUE, INTESTINAL DISORDERS AND ALTERATIONS IN SLEEP AND MOOD. IT IS ESTIMATED THAT TWO TO EIGHT PERCENT OF THE WORLD POPULATION IS AFFECTED BY FIBROMYALGIA. FROM A MEDICAL POINT OF VIEW, THIS PATHOLOGY STILL PRESENTS INEXPLICABLE ASPECTS. IT IS KNOWN THAT FIBROMYALGIA IS CAUSED BY A CENTRAL SENSITIZATION PHENOMENON CHARACTERIZED BY THE DYSFUNCTION OF NEURO-CIRCUITS, WHICH INVOLVES THE PERCEPTION, TRANSMISSION AND PROCESSING OF AFFERENT NOCICEPTIVE STIMULI, WITH THE PREVALENT MANIFESTATION OF PAIN AT THE LEVEL OF THE LOCOMOTOR SYSTEM. IN RECENT YEARS, THE PATHOGENESIS OF FIBROMYALGIA HAS ALSO BEEN LINKED TO OTHER FACTORS, SUCH AS INFLAMMATORY, IMMUNE, ENDOCRINE, GENETIC AND PSYCHOSOCIAL FACTORS. A RHEUMATOLOGIST TYPICALLY MAKES A DIAGNOSIS OF FIBROMYALGIA WHEN THE PATIENT DESCRIBES A HISTORY OF PAIN SPREADING IN ALL QUADRANTS OF THE BODY FOR AT LEAST THREE MONTHS AND WHEN PAIN IS CAUSED BY DIGITAL PRESSURE IN AT LEAST 11 OUT OF 18 ALLOGENIC POINTS, CALLED TENDER POINTS. FIBROMYALGIA DOES NOT INVOLVE ORGANIC DAMAGE, AND SEVERAL DIAGNOSTIC APPROACHES HAVE BEEN DEVELOPED IN RECENT YEARS, INCLUDING THE ANALYSIS OF GENETIC, EPIGENETIC AND SEROLOGICAL BIOMARKERS. SYMPTOMS OFTEN BEGIN AFTER PHYSICAL OR EMOTIONAL TRAUMA, BUT IN MANY CASES, THERE APPEARS TO BE NO OBVIOUS TRIGGER. WOMEN ARE MORE PRONE TO DEVELOPING THE DISEASE THAN MEN. UNFORTUNATELY, THE CONVENTIONAL MEDICAL THERAPIES THAT TARGET THIS PATHOLOGY PRODUCE LIMITED BENEFITS. THEY REMAIN LARGELY PHARMACOLOGICAL IN NATURE AND TEND TO TREAT THE SYMPTOMATIC ASPECTS OF VARIOUS DISORDERS REPORTED BY THE PATIENT. THE STATISTICS, HOWEVER, HIGHLIGHT THE FACT THAT 90% OF PEOPLE WITH FIBROMYALGIA ALSO TURN TO COMPLEMENTARY MEDICINE TO MANAGE THEIR SYMPTOMS. 2021 18 812 67 CHANGES IN DNA METHYLATION PROFILES OF MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME PATIENTS REFLECT SYSTEMIC DYSFUNCTIONS. BACKGROUND: MYALGIC ENCEPHALOMYELITIS/CHRONIC FATIGUE SYNDROME (ME/CFS) IS A LIFELONG DEBILITATING DISEASE WITH A COMPLEX PATHOLOGY NOT YET CLEARLY DEFINED. SUSCEPTIBILITY TO ME/CFS INVOLVES GENETIC PREDISPOSITION AND EXPOSURE TO ENVIRONMENTAL FACTORS, SUGGESTING AN EPIGENETIC ASSOCIATION. EPIGENETIC STUDIES WITH OTHER ME/CFS COHORTS HAVE USED ARRAY-BASED TECHNOLOGY TO IDENTIFY DIFFERENTIALLY METHYLATED INDIVIDUAL SITES. CHANGES IN RNA QUANTITIES AND PROTEIN ABUNDANCE HAVE BEEN DOCUMENTED IN OUR PREVIOUS INVESTIGATIONS WITH THE SAME ME/CFS COHORT USED FOR THIS STUDY. RESULTS: DNA FROM A WELL-CHARACTERISED NEW ZEALAND COHORT OF 10 ME/CFS PATIENTS AND 10 AGE-/SEX-MATCHED HEALTHY CONTROLS WAS ISOLATED FROM PERIPHERAL BLOOD MONONUCLEAR (PBMC) CELLS, AND USED TO GENERATE REDUCED GENOME-SCALE DNA METHYLATION MAPS USING REDUCED REPRESENTATION BISULPHITE SEQUENCING (RRBS). THE SEQUENCING DATA WERE ANALYSED UTILISING THE DMAP ANALYSIS PIPELINE TO IDENTIFY DIFFERENTIALLY METHYLATED FRAGMENTS, AND THE METHYLKIT PIPELINE WAS USED TO QUANTIFY METHYLATION DIFFERENCES AT INDIVIDUAL CPG SITES. DMAP IDENTIFIED 76 DIFFERENTIALLY METHYLATED FRAGMENTS AND METHYLKIT IDENTIFIED 394 DIFFERENTIALLY METHYLATED CYTOSINES THAT INCLUDED BOTH HYPER- AND HYPO-METHYLATION. FOUR CLUSTERS WERE IDENTIFIED WHERE DIFFERENTIALLY METHYLATED DNA FRAGMENTS OVERLAPPED WITH OR WERE WITHIN CLOSE PROXIMITY TO MULTIPLE DIFFERENTIALLY METHYLATED INDIVIDUAL CYTOSINES. THESE CLUSTERS IDENTIFIED REGULATORY REGIONS FOR 17 PROTEIN ENCODING GENES RELATED TO METABOLIC AND IMMUNE ACTIVITY. ANALYSIS OF DIFFERENTIALLY METHYLATED GENE BODIES (EXONS/INTRONS) IDENTIFIED 122 UNIQUE GENES. COMPARISON WITH OTHER STUDIES ON PBMCS FROM ME/CFS PATIENTS AND CONTROLS WITH ARRAY TECHNOLOGY SHOWED 59% OF THE GENES IDENTIFIED IN THIS STUDY WERE ALSO FOUND IN ONE OR MORE OF THESE STUDIES. FUNCTIONAL PATHWAY ENRICHMENT ANALYSIS IDENTIFIED 30 ASSOCIATED PATHWAYS. THESE INCLUDED IMMUNE, METABOLIC AND NEUROLOGICAL-RELATED FUNCTIONS DIFFERENTIALLY REGULATED IN ME/CFS PATIENTS COMPARED TO THE MATCHED HEALTHY CONTROLS. CONCLUSIONS: MAJOR DIFFERENCES WERE IDENTIFIED IN THE DNA METHYLATION PATTERNS OF ME/CFS PATIENTS THAT CLEARLY DISTINGUISHED THEM FROM THE HEALTHY CONTROLS. OVER HALF FOUND IN GENE BODIES WITH RRBS IN THIS STUDY HAD BEEN IDENTIFIED IN OTHER ME/CFS STUDIES USING THE SAME CELLS BUT WITH ARRAY TECHNOLOGY. WITHIN THE ENRICHED FUNCTIONAL IMMUNE, METABOLIC AND NEUROLOGICAL PATHWAYS, A NUMBER OF ENRICHED NEUROTRANSMITTER AND NEUROPEPTIDE REACTOME PATHWAYS HIGHLIGHTED A DISTURBED NEUROLOGICAL PATHOPHYSIOLOGY WITHIN THE PATIENT GROUP. 2020 19 1637 45 DOES DYSREGULATION OF KEY EPIGENETIC AND BIOCHEMICAL PATHWAYS OCCUR IN POSTULATED VASOACTIVE NEUROPEPTIDE AUTOIMMUNE DISORDERS? AUTOIMMUNE DYSFUNCTION OF CERTAIN VASOACTIVE NEUROPEPTIDES (VNS) HAS BEEN POSTULATED AS A CONTRIBUTING CAUSE OF SUDDEN INFANT DEATH SYNDROME (SIDS), CHRONIC FATIGUE SYNDROME (CFS), GULF WAR SYNDROME (GWS) AND OTHER FATIGUE-RELATED DISORDERS. THIS FAMILY OF VNS INCLUDES PITUITARY ADENYLATE CYCLASE ACTIVATING POLYPEPTIDE (PACAP), VASOACTIVE INTESTINAL PEPTIDE (VIP) AND CALCITONIN GENE RELATED PEPTIDE (CGRP). THE POSTULATED MECHANISM IS COMPROMISE OF ADENYLATE CYCLASE ACTIVATION, A VITAL AND UNIQUE STEP IN CYCLIC AMP PRODUCTION FROM ATP, THROUGH AUTOIMMUNE DYSFUNCTION OF VNS, THEIR RECEPTORS OR THEIR GENES POSSIBLY INVOLVING CYTOSINE-PHOSPHATE-GUANINE (CPG) FRAGMENTS. CPG FRAGMENTS ARE IMMUNOMODULATORY DINUCLEOTIDES SERVING AS 'FRIEND OR FOE' RECOGNITION SYSTEMS TO DIFFERENTIATE BACTERIAL AND VIRAL (HYPOMETHYLATED CPG) FROM MAMMALIAN (METHYLATED CPG) DNA. HOWEVER HYPOMETHYLATION DISORDERS AFFECTING THESE FRAGMENTS IN MAMMALS MAY CONVERT THEM TO DYSFUNCTIONAL STATES BY PROMOTING AUTOIMMUNE INFLAMMATORY REACTIONS. EPIGENETIC MECHANISMS ACTING ON GENE PROMOTER REGIONS MAY CONTRIBUTE TO THE DEVELOPMENT OF VN AUTOIMMUNE FATIGUE-RELATED DISORDERS THROUGH CPG FRAGMENTS LOCATED IN VITAL SEGMENTS OF VN/RECEPTOR GENES BY CAUSING SIGNALLING DEFECTS WITH PROFOUND IMPLICATIONS FOR VN FUNCTION. NEUROTRANSMITTER DYSFUNCTION PARTICULARLY GLUTAMATERGIC TRANSMISSION COULD ALSO RESULT WITH DISRUPTION OF NEURONAL CELLULAR BIOCHEMICAL FUNCTIONS SUCH AS AMMONIA REGULATION. ENDOSOMAL ACIDITY AND MITOCHONDRIAL MEMBRANE POTENTIAL MODIFIERS SUCH AS CHLOROQUINE, TOGETHER WITH IMMUNOREGULATORY THERAPIES, MAY HAVE THERAPEUTIC IMPLICATIONS IN PROTECTING AGAINST THESE APPARENT AUTOIMMUNE DISORDERS. THIS PAPER EXAMINES SPECIFIC EPIGENETIC AND BIOCHEMICAL MECHANISMS POSSIBLY MEDIATED BY VN OR RECEPTOR GENES RESULTING IN POSTULATED VN AUTOIMMUNE FATIGUE-RELATED DISORDERS. THESE MECHANISMS MAY HAVE IMPLICATIONS FOR TREATMENT AND PREVENTION OPTIONS FOR VN AUTOIMMUNE DISORDERS. VN AUTOIMMUNE PROCESSES HAVE IMPLICATIONS FOR MILITARY MEDICINE WHERE RADIOLOGICAL, CHEMICAL AND BIOLOGICAL AGENTS MAY PLAY AN IMPORTANT ROLE IN PATHOGENESIS. 2005 20 5280 25 PROMOTING SYMPATHOVAGAL BALANCE IN MULTIPLE SCLEROSIS; PHARMACOLOGICAL, NON-PHARMACOLOGICAL, AND SURGICAL STRATEGIES. ACCUMULATED EVIDENCE SUGGESTS THAT CARDIOVASCULAR AUTONOMIC NERVOUS SYSTEM (ANS) DYSFUNCTION MAY BE THE UNDERLYING CAUSE OF MANY MS CLINICAL PRESENTATIONS, INCLUDING NEURODEGENERATION AND REDUCED RESPONSE TO IMMUNOMODULATORY THERAPIES, DEPRESSION, FATIGUE AND SLEEP DISORDERS, MIGRAINE, OSTEOPOROSIS, AND CHRONIC CEREBROSPINAL VENOUS INSUFFICIENCY, THE NEWER MS VASCULAR ETIOLOGY. WE HAVE RECENTLY DESCRIBED THE GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS WITH THE POTENTIAL INFLUENCING ANS ACTIVITY, AND THE INTERACTIONS AMONG THESE FACTORS. THIS REVIEW EXPANDS UPON PREVIOUS ONES, DESCRIBING THE PHARMACOLOGICAL, NON-PHARMACOLOGICAL, AND SURGICAL STRATEGIES THAT COULD BE ADOPTED TO PREVENT AND MINIMIZE THE DETERIORATION IN ANS FUNCTION, PROMOTING A STATE OF SYMPATHOVAGAL BALANCE. HOWEVER, THESE STRATEGIES SHOULD NOT BE APPLIED AS "ONE SIZE FITS ALL", BUT SHOULD TAKE INTO ACCOUNT THE NATURE AND THE DEGREE OF ANS DYSFUNCTION. THESE STRATEGIES WOULD BE EFFECTIVE IN IMPROVING ANS FUNCTION NOT ONLY IN MS, BUT ALSO IN OTHER AUTOIMMUNE AND NEURODEGENERATIVE DISEASES, WHERE THE DYSFUNCTION OF THIS SYSTEM PLAYS A ROLE. 2016