1 3463 137 HYPOTHALAMIC-PITUITARY-ADRENAL AND HYPOTHALAMIC-PITUITARY-GONADAL AXES: SEX DIFFERENCES IN REGULATION OF STRESS RESPONSIVITY. GONADAL HORMONES PLAY A KEY ROLE IN THE ESTABLISHMENT, ACTIVATION, AND REGULATION OF THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS. BY INFLUENCING THE RESPONSE AND SENSITIVITY TO RELEASING FACTORS, NEUROTRANSMITTERS, AND HORMONES, GONADAL STEROIDS HELP ORCHESTRATE THE GAIN OF THE HPA AXIS TO FINE-TUNE THE LEVELS OF STRESS HORMONES IN THE GENERAL CIRCULATION. FROM EARLY LIFE TO ADULTHOOD, GONADAL STEROIDS CAN DIFFERENTIALLY AFFECT THE HPA AXIS, RESULTING IN SEX DIFFERENCES IN THE RESPONSIVITY OF THIS AXIS. THE HPA AXIS INFLUENCES MANY PHYSIOLOGICAL FUNCTIONS MAKING AN ORGANISM'S RESPONSE TO CHANGES IN THE ENVIRONMENT APPROPRIATE FOR ITS REPRODUCTIVE STATUS. ALTHOUGH THE ACUTE HPA RESPONSE TO STRESSORS IS A BENEFICIAL RESPONSE, CONSTANT ACTIVATION OF THIS CIRCUITRY BY CHRONIC OR TRAUMATIC STRESSFUL EPISODES MAY LEAD TO A DYSREGULATION OF THE HPA AXIS AND CAUSE PATHOLOGY. COMPARED TO MALES, FEMALE MICE AND RATS SHOW A MORE ROBUST HPA AXIS RESPONSE, AS A RESULT OF CIRCULATING ESTRADIOL LEVELS WHICH ELEVATE STRESS HORMONE LEVELS DURING NON-THREATENING SITUATIONS, AND DURING AND AFTER STRESSORS. FLUCTUATING LEVELS OF GONADAL STEROIDS IN FEMALES ACROSS THE ESTROUS CYCLE ARE A MAJOR FACTOR CONTRIBUTING TO SEX DIFFERENCES IN THE ROBUSTNESS OF HPA ACTIVITY IN FEMALES COMPARED TO MALES. MOREOVER, GONADAL STEROIDS MAY ALSO CONTRIBUTE TO EPIGENETIC AND ORGANIZATIONAL INFLUENCES ON THE HPA AXIS EVEN BEFORE PUBERTY. CORRESPONDINGLY, CROSSTALK BETWEEN THE HYPOTHALAMIC-PITUITARY-GONADAL (HPG) AND HPA AXES COULD LEAD TO ABNORMALITIES OF STRESS RESPONSES. IN HUMANS, A DYSREGULATED STRESS RESPONSE IS ONE OF THE MOST COMMON SYMPTOMS SEEN ACROSS MANY NEUROPSYCHIATRIC DISORDERS, AND AS A RESULT, SUCH INTERACTIONS MAY EXACERBATE PERIPHERAL PATHOLOGIES. IN THIS REVIEW, WE DISCUSS THE HPA AND HPG AXES AND REVIEW HOW GONADAL STEROIDS INTERACT WITH THE HPA AXIS TO REGULATE THE STRESS CIRCUITRY DURING ALL STAGES IN LIFE. 2017 2 1460 32 DISORDERS OF CONSCIOUSNESS AND PHARMACEUTICALS THAT ACT ON OXYGEN BASED AMINO ACID AND MONOAMINE NEUROTRANSMITTER PATHWAYS OF THE BRAIN. OXYGEN BASED NEUROTRANSMITTERS IN THE SYNAPSES OF THE BRAIN ARE PROPOSED TO PLAY AN IMPORTANT ROLE IN THE GENERATION OF CONSCIOUSNESS. THEY INCLUDE THE AMINO ACIDS GLUTAMATE AND GABA WHICH USE KREBS CYCLE PRECURSORS FOR THEIR SYNTHESIS, AND THE MONOAMINES DOPAMINE, NORADRENALIN, ADRENALIN AND SEROTONIN, WHICH ARE DERIVED FROM TYROSINE AND TRYPTOPHAN. DURING ISCHEMIA AFTER AN ACUTE BRAIN INJURY, A GABA SURGE OFTEN INITIATES BRAIN SUPPRESSION. IT HAS BEEN PROPOSED THAT WITH CHRONIC ISCHEMIA, A SECONDARY, POSSIBLY EPIGENETIC RESPONSE OCCURS WHEN NEUROTRANSMITTERS DEPLETE, A GLUCOSE AND OXYGEN SAVING MECHANISM TERMED NEURODORMANCY THAT MAY INVOKE ALTERNATIVE LONG TERM LOW ENERGY METABOLIC PATHWAYS IN THE BRAIN, ENCOUNTERED IN DISORDERS OF CONSCIOUSNESS. SOME MEDICATIONS CAN REVERSE DISORDERS OF CONSCIOUSNESS IN SOME PATIENTS. VIRTUALLY ALL OF THEM ACT ON NEUROTRANSMITTER SYSTEMS THAT USE OXYGEN AS A BUILDING BLOCK OR AS AN ENERGY SOURCE WITHIN THE BRAIN. PHARMACEUTICALS THAT ACT IN THE OXYGEN BASED AMINO ACID SYSTEMS OF THE BRAIN INCLUDE THE GABAERGIC MEDICATIONS ZOLPIDEM AND BACLOFEN, WHILE THOSE THAT ACT IN THE MONOAMINE AXES INCLUDE THE DOPAMINERGIC MEDICATIONS L DOPA, AMANTADINE, BROMOCRIPTINE, APOMORPHINE AND METHYLPHENIDATE, AND THE NORADRENERGIC AND SEROTONERGIC MEDICATIONS DESIPRAMINE, AMITRIPTYLINE, PROTRIPTYLINE AND FLUOXETINE. ANOTHER GROUP ARE THE CHOLINESTERASE INHIBITORS, RESPONSIBLE FOR INCREASING ACETYLCHOLINE, WHICH IS SYNTHESIZED FROM THE KREBS CYCLE INITIATOR, ACETYL COA. IT APPEARS THAT PHARMACEUTICALS THAT ARE ACTIVE IN THE OXYGEN BASED NEUROTRANSMITTER PATHWAYS OF THE BRAIN ARE SUCCESSFUL TO AROUSE TO CONSCIOUSNESS PATIENTS THAT SUFFER FROM ITS DISORDERS. RESEARCH NEEDS TO BE SUPPORTED AS FOUNDATION TO UNDERSTAND THE BIOCHEMICAL MECHANISMS THAT ARE INVOLVED IN CONSCIOUSNESS DISORDERS AND TO EXPLORE FURTHER THE PHARMACOLOGICAL TREATMENT POSSIBILITIES FOR THESE DEVASTATING NEUROLOGICAL CONDITIONS. 2014 3 5209 43 PRENATAL XENOBIOTIC EXPOSURE AND INTRAUTERINE HYPOTHALAMUS-PITUITARY-ADRENAL AXIS PROGRAMMING ALTERATION. THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS IS ONE OF THE MOST IMPORTANT NEUROENDOCRINE AXES AND PLAYS AN IMPORTANT ROLE IN STRESS DEFENSE RESPONSES BEFORE AND AFTER BIRTH. PRENATAL EXPOSURE TO XENOBIOTICS, INCLUDING ENVIRONMENTAL TOXINS (SUCH AS SMOKE, SULFUR DIOXIDE AND CARBON MONOXIDE), DRUGS (SUCH AS SYNTHETIC GLUCOCORTICOIDS), AND FOODS AND BEVERAGE CATEGORIES (SUCH AS ETHANOL AND CAFFEINE), AFFECTS FETAL DEVELOPMENT INDIRECTLY BY CHANGING THE MATERNAL STATUS OR DAMAGING THE PLACENTA. CERTAIN XENOBIOTICS (SUCH AS CAFFEINE, ETHANOL AND DEXAMETHASONE) MAY ALSO AFFECT THE FETUS DIRECTLY BY CROSSING THE PLACENTA INTO THE FETUS DUE TO THEIR LIPOPHILIC PROPERTIES AND LOWER MOLECULAR WEIGHTS. ALL OF THESE FACTORS PROBABLY RESULT IN INTRAUTERINE PROGRAMMING ALTERATION OF THE HPA AXIS, WHICH SHOWED A LOW BASAL ACTIVITY BUT HYPERSENSITIVITY TO CHRONIC STRESS. THESE ALTERATIONS WILL, THEREFORE, INCREASE THE SUSCEPTIBILITY TO ADULT NEUROPSYCHIATRIC (SUCH AS DEPRESSION AND SCHIZOPHRENIA) AND METABOLIC DISEASES (SUCH AS HYPERTENSION, DIABETES AND NON-ALCOHOLIC FATTY LIVER DISEASE). THE "OVER-EXPOSURE OF FETUSES TO MATERNAL GLUCOCORTICOIDS" MAY BE THE MAIN INITIATION FACTOR BY WHICH THE FETAL HPA AXIS PROGRAMMING IS ALTERED. MEANTIME, XENOBIOTICS CAN DIRECTLY INDUCE ABNORMAL EPIGENETIC MODIFICATIONS AND EXPRESSION ON THE IMPORTANT FETAL GENES (SUCH AS HIPPOCAMPAL GLUCOCORTICOID RECEPTOR, ADRENAL STEROIDOGENIC ACUTE REGULATORY PROTEIN, ET AL) OR DAMAGE BY IN SITU OXIDATIVE METABOLISM OF FETAL ADRENALS, WHICH MAY ALSO BE CONTRIBUTED TO THE PROGRAMMING ALTERATION OF FETAL HPA AXIS. 2014 4 5450 35 REPRODUCTIVE TOXICITY OF COMBINED EFFECTS OF ENDOCRINE DISRUPTORS ON HUMAN REPRODUCTION. CONFLUENCE OF ENVIRONMENTAL, GENETIC, AND LIFESTYLE VARIABLES IS RESPONSIBLE FOR DETERIORATION OF HUMAN FECUNDITY. ENDOCRINE DISRUPTORS OR ENDOCRINE DISRUPTING CHEMICALS (EDCS) MAY BE FOUND IN A VARIETY OF FOODS, WATER, AIR, BEVERAGES, AND TOBACCO SMOKE. IT HAS BEEN DEMONSTRATED IN EXPERIMENTAL INVESTIGATIONS THAT A WIDE RANGE OF ENDOCRINE DISRUPTING CHEMICALS HAVE NEGATIVE EFFECTS ON HUMAN REPRODUCTIVE FUNCTION. HOWEVER, EVIDENCE ON THE REPRODUCTIVE CONSEQUENCES OF HUMAN EXPOSURE TO ENDOCRINE DISRUPTING CHEMICALS IS SPARSE AND/OR CONFLICTING IN THE SCIENTIFIC LITERATURE. THE COMBINED TOXICOLOGICAL ASSESSMENT IS A PRACTICAL METHOD FOR ASSESSING THE HAZARDS OF COCKTAILS OF CHEMICALS, CO-EXISTING IN THE ENVIRONMENT. THE CURRENT REVIEW PROVIDES A COMPREHENSIVE OVERVIEW OF STUDIES EMPHASIZING THE COMBINED TOXICITY OF ENDOCRINE DISRUPTING CHEMICALS ON HUMAN REPRODUCTION. ENDOCRINE DISRUPTING CHEMICALS INTERACT WITH EACH OTHER TO DISRUPT THE DIFFERENT ENDOCRINE AXES, RESULTING IN SEVERE GONADAL DYSFUNCTIONS. TRANSGENERATIONAL EPIGENETIC EFFECTS HAVE ALSO BEEN INDUCED IN GERM CELLS, MOSTLY THROUGH DNA METHYLATION AND EPIMUTATIONS. SIMILARLY, AFTER ACUTE OR CHRONIC EXPOSURE TO ENDOCRINE DISRUPTING CHEMICALS COMBINATIONS, INCREASED OXIDATIVE STRESS (OS), ELEVATED ANTIOXIDANT ENZYMATIC ACTIVITY, DISRUPTED REPRODUCTIVE CYCLE, AND REDUCED STEROIDOGENESIS ARE OFTEN REPORTED CONSEQUENCES. THE ARTICLE ALSO DISCUSSES THE CONCENTRATION ADDITION (CA) AND INDEPENDENT ACTION (IA) PREDICTION MODELS, WHICH REVEAL THE IMPORTANCE OF VARIOUS SYNERGISTIC ACTIONS OF ENDOCRINE DISRUPTING CHEMICALS MIXTURES. MORE CRUCIALLY, THIS EVIDENCE-BASED STUDY ADDRESSES THE RESEARCH LIMITATIONS AND INFORMATION GAPS, AS WELL AS PARTICULARLY PRESENTS THE FUTURE RESEARCH VIEWS ON COMBINED ENDOCRINE DISRUPTING CHEMICALS TOXICITY ON HUMAN REPRODUCTION. 2023 5 992 36 CHRONIC STRESS AND ADIPOSE TISSUE IN THE ANOREXIC STATE: ENDOCRINE AND EPIGENETIC MECHANISMS. ALTHOUGH ADIPOSE TISSUE METABOLISM IN OBESITY HAS BEEN WIDELY STUDIED, THERE IS LIMITED RESEARCH ON THE ANOREXIC STATE, WHERE THE ENDOCRINE SYSTEM IS DISRUPTED BY REDUCED ADIPOSE TISSUE MASS AND THERE ARE DEPOT-SPECIFIC CHANGES IN ADIPOCYTE TYPE AND FUNCTION. STRESS EXPOSURE AT DIFFERENT STAGES OF LIFE CAN ALTER THE BALANCE BETWEEN ENERGY INTAKE AND EXPENDITURE AND THEREBY CONTRIBUTE TO THE PATHOGENESIS OF ANOREXIA NERVOSA. THIS REVIEW INTEGRATES INFORMATION FROM HUMAN CLINICAL TRIALS TO DESCRIBE ENDOCRINE, GENETIC AND EPIGENETIC ASPECTS OF ADIPOSE TISSUE PHYSIOLOGY IN THE ANOREXIC CONDITION. CHANGES IN THE HYPOTHALAMUS-PITUITARY-THYROID, -ADRENAL, AND -GONADAL AXES AND THEIR RELATIONSHIPS TO APPETITE REGULATION AND ADIPOCYTE FUNCTION ARE DISCUSSED. BECAUSE OF THE ROLE OF STRESS IN TRIGGERING OR MAGNIFYING ANOREXIA, AND THE DYNAMIC BUT ALSO PERSISTENT NATURE OF ENVIRONMENTALLY-INDUCED EPIGENETIC MODIFICATIONS, EPIGENETICS IS LIKELY THE LINK BETWEEN STRESS AND LONG-TERM CHANGES IN THE ENDOCRINE SYSTEM THAT DISRUPT HOMOEOSTATIC FOOD INTAKE AND ADIPOSE TISSUE METABOLISM. HEREIN, WE FOCUS ON THE ADIPOCYTE AND CHANGES IN ITS FUNCTION, INCLUDING ALTERATIONS REINFORCED BY ENDOCRINE DISTURBANCE AND DYSFUNCTIONAL ADIPOKINE REGULATION. THIS INFORMATION IS CRITICAL BECAUSE OF THE POOR UNDERSTANDING OF ANOREXIC PATHOPHYSIOLOGY, DUE TO THE LACK OF SUITABLE RESEARCH MODELS, AND THE COMPLEXITY OF GENETIC AND ENVIRONMENTAL INTERACTIONS. 2020 6 4067 25 MATERNAL AND PEDIATRIC HEALTH AND DISEASE: INTEGRATING BIOPSYCHOSOCIAL MODELS AND EPIGENETICS. THE CONCEPTS OF ALLOSTASIS (STABILITY THROUGH ADAPTATION) AND ACCUMULATED LIFE STRESS (MCEWEN'S ALLOSTATIC LOAD) AIM TO UNDERSTAND CHILDHOOD AND ADULT OUTCOMES. CHRONIC MALNUTRITION, CHANGES IN SOCIAL CONDITION, AND ADVERSE EARLY-LIFE EXPERIENCES MAY PROGRAM PHENOTYPES AND CONTRIBUTE TO LONG-LASTING DISEASE RISK. HOWEVER, INTEGRATION OF LIFE COURSE APPROACHES, SOCIAL AND ECONOMIC CONTEXTS, AND COMPARISON AMONG DIFFERENT BIOPSYCHOSOCIAL MODELS HAS NOT GENERALLY BEEN EXPLORED. THIS REVIEW CRITICALLY EXAMINES THE LITERATURE AND EVALUATES RECENT INSIGHTS INTO HOW ENVIRONMENTAL STRESS CAN ALTER LIFELONG HYPOTHALAMIC-PITUITARY-ADRENAL AXIS AND IMMUNE SYSTEM RESPONSIVENESS AND INDUCE METABOLIC AND NEURODEVELOPMENTAL MALADAPTATION. MODELS OF BIOPSYCHOSOCIAL STRESS OVERLAP BUT MAY CONSIDER DIFFERENT CONDITIONS. CONCEPTS INCLUDE ALLOSTASIS, WHICH INCORPORATES HORMONAL RESPONSES TO PREDICTABLE ENVIRONMENTAL CHANGES, AND GERONIMUS'S "WEATHERING," WHICH AIMS TO EXPLAIN HOW SOCIALLY STRUCTURED, REPEATED STRESS CAN ACCUMULATE AND INCREASE DISEASE VULNERABILITY. WEATHERING EMPHASIZES ROLES OF INTERNALIZED/INTERPERSONAL RACISM IN OUTCOMES DISPARITIES. FOR MEXICAN IMMIGRANTS AND MEXICAN AMERICANS, THE "ACCULTURATION" FRAMEWORK HAS PROVEN ESPECIALLY USEFUL TO EXPLORE DISPARITIES, INCLUDING PRETERM BIRTH AND NEUROPSYCHIATRIC RISKS IN CHILDHOOD. COMPLEXITIES OF STRESS ASSESSMENTS AND RECENT RESEARCH INTO EPIGENETIC MECHANISMS MEDIATING EFFECTS OF PHYSICAL, NUTRITIONAL, PSYCHOLOGICAL, AND SOCIAL STRESS ARE REVIEWED. 2016 7 4797 25 NUTRITIONAL INTERVENTIONS TO IMPROVE BRAIN OUTCOMES IN PRETERM INFANTS. THE LAST 20 YEARS HAVE SEEN DRAMATIC IMPROVEMENTS IN SURVIVAL FOR PRETERM INFANTS IN BOTH HIGH- AND LOW-INCOME SETTINGS. SURVIVAL RATES OF OVER 50% IN INFANTS BORN 16 WEEKS EARLY (24 WEEKS' GESTATION) ARE NOW COMMONPLACE IN WELL-RESOURCED NEONATAL INTENSIVE CARE UNITS. HOWEVER, ENSURING ADEQUATE NUTRIENT INTAKES ESPECIALLY IN THE FIRST FEW DAYS AND WEEKS IS CHALLENGING, AND MANY INFANTS SHOW POOR GROWTH AND NUTRITIONAL STATUS. GOOD NUTRITIONAL MANAGEMENT SHOULD BE SEEN AS THE CORNERSTONE OF GOOD NEONATAL CARE AND IS KEY TO IMPROVING A RANGE OF IMPORTANT OUTCOMES INCLUDING REDUCED RATES OF RETINOPATHY OF PREMATURITY, CHRONIC LUNG DISEASE, NECROTIZING ENTEROCOLITIS (NEC), AND SEPSIS. EQUALLY IMPORTANTLY, IS THAT GOOD NUTRITIONAL STATUS IS ESSENTIAL TO OPTIMIZE BRAIN GROWTH AND DIFFERENTIATION. THERE ARE MULTIPLE POTENTIAL MECHANISMS THAT LINK NUTRITION TO BRAIN OUTCOMES IN PRETERM INFANTS INCLUDING NEEDS FOR TISSUE ACCRETION, ENERGY SUPPLY, SIGNALING ROLES, FUNCTIONAL COMPONENTS IN HUMAN MILK, EPIGENETIC REGULATION, PREVENTION OF NEC AND DISEASE, AND IMPACTS ON THE GUT BRAIN AXES. THIS ARTICLE WILL REVIEW DATA IN SUPPORT OF DIFFERENT MECHANISTIC LINKS FOR THE IMPACT OF NUTRITION ON BRAIN OUTCOMES IN PRETERM INFANTS. 2021 8 6478 29 TOPICAL REVIEW: THE EMERGING FIELD OF EPIGENETICS: INFORMING MODELS OF PEDIATRIC TRAUMA AND PHYSICAL HEALTH. OBJECTIVE: TRAUMA EXPERIENCED DURING CHILDHOOD AND ADOLESCENCE HAS BEEN LINKED TO A NUMBER OF CHRONIC MEDICAL CONCERNS. WE HIGHLIGHT MAJOR FINDINGS FROM THE PEDIATRIC TRAUMA LITERATURE TO PROVIDE A MODEL FOR UNDERSTANDING THIS ASSOCIATION. METHODS: STUDIES EXAMINING THE EFFECTS OF TRAUMA WERE SYSTEMATICALLY REVIEWED AND SYNTHESIZED INTO A MODEL PROPOSING A CENTRAL ROLE FOR EPIGENETICS IN THE WAYS THAT CHILDHOOD EXPERIENCES CAN AFFECT HEALTH. RESULTS: EARLY HYPOTHALAMIC PITUITARY ADRENAL (HPA) AXIS RESPONSE MAY IMPACT INITIAL TRAUMA EXPERIENCE, WITH DOWNSTREAM EFFECTS ON POSTTRAUMA ADJUSTMENT REFLECTED IN POSTTRAUMA NEUROBIOLOGY, PSYCHOLOGICAL HEALTH, AND PHYSICAL HEALTH. CONCLUSIONS: PROSPECTIVE RESEARCH WITH CHILDREN AND ADOLESCENTS EXPOSED TO TRAUMA IS NEEDED TO BETTER CHARACTERIZE THE GENETIC AND EPIGENETIC INFLUENCES ON THE COURSE OF HPA AND IMMUNE PROCESSES AS RELATED TO POSTTRAUMA PSYCHOLOGICAL AND PHYSICAL HEALTH OUTCOMES. 2016 9 5107 42 POLYCYSTIC OVARY SYNDROME: A BRAIN DISORDER CHARACTERIZED BY EATING PROBLEMS ORIGINATING DURING PUBERTY AND ADOLESCENCE. POLYCYSTIC OVARY SYNDROME (PCOS) IS AN ENDOCRINE CONDITION ASSOCIATED WITH REPRODUCTIVE AND PSYCHIATRIC DISORDERS, AND WITH OBESITY. EATING DISORDERS, SUCH AS BULIMIA AND RECURRENT DIETING, ARE ALSO LINKED TO PCOS. THEY CAN LEAD TO THE EPIGENETIC DYSREGULATION OF THE HYPOTHALAMIC-PITUITARY-GONADAL (HPG) AXIS, THEREBY IMPACTING ON OVARIAN FOLLICULOGENESIS. WE POSTULATE THAT PCOS IS INDUCED BY PSYCHOLOGICAL DISTRESS AND EPISODES OF OVEREATING AND/OR DIETING DURING PUBERTY AND ADOLESCENCE, WHEN BODY DISSATISFACTION AND EMOTIONAL DISTRESS ARE OFTEN PRESENT. WE PROPOSE THAT UPREGULATED ACTIVATION OF THE CENTRAL HPG AXIS DURING THIS PERIOD CAN BE EPIGENETICALLY ALTERED BY PSYCHOLOGICAL STRESSORS AND BY BULIMIA/RECURRENT DIETING, WHICH ARE COMMON DURING ADOLESCENCE AND WHICH CAN LEAD TO PCOS. THIS HYPOTHESIS IS BASED ON EVENTS THAT OCCUR DURING A LARGELY NEGLECTED STAGE OF FEMALE REPRODUCTIVE DEVELOPMENT. TO DATE, MOST RESEARCH INTO THE ORIGINS OF PCOS HAS FOCUSED ON THE PRENATAL INDUCTION OF THIS DISORDER, PARTICULARLY IN UTERO ANDROGENIZATION AND THE ROLE OF ANTI-MULLERIAN HORMONE. ESTABLISHING CAUSALITY IN OUR PERIPUBERTAL MODEL REQUIRES PROSPECTIVE COHORT STUDIES FROM INFANCY. MECHANISTIC STUDIES SHOULD CONSIDER THE ROLE OF THE GUT MICROBIOTA IN ADDITION TO THE EPIGENETIC REGULATION OF (NEURO) HORMONES. FINALLY, CLINICIANS SHOULD CONSIDER THE IMPORTANCE OF UNDERLYING CHRONIC PSYCHOLOGICAL DISTRESS AND EATING DISORDERS IN PCOS. 2020 10 5830 45 STRESS, THYROID DYSREGULATION, AND THYROID CANCER IN CHILDREN AND ADOLESCENTS: PROPOSED IMPENDING MECHANISMS. STRESS IS A POTENTIAL CATALYST FOR THYROID DYSREGULATION THROUGH CROSS-COMMUNICATION OF THE HYPOTHALAMIC-PITUITARY-ADRENAL AND HYPOTHALAMIC-PITUITARY-THYROID (HPT) AXES. STRESS AND STRESSORS EXPOSURE MOTIVATES MOLECULAR MECHANISMS AFFECTING COMPOUND FEEDBACK LOOPS OF THE HPT AXIS. WHILE THERE IS EVIDENCE OF CONNECTION BETWEEN STRESS AND THYROID DYSREGULATION, THE QUESTION WHETHER THIS CONNECTION IS IMPLICATED IN THE DEVELOPMENT OF THYROID CANCER (TC) REMAINS UNANSWERED. IN VIEW OF THE RISING INCIDENCE OF TC IN BOTH ADULTS AND CHILDREN ALONGSIDE THE INCREASING STRESS IN OUR MODERN SOCIETY, THERE IS A NEED TO UNDERSTAND POSSIBLE INTERRELATIONS BETWEEN STRESS, THYROID DYSREGULATION, AND TC. PROLONGED GLUCOCORTICOID SECRETION DUE TO STRESS INTERFERES WITH IMMUNE SYSTEM RESPONSE BY ALTERING THE CYTOKINES, INDUCING LOW-GRADE CHRONIC INFLAMMATION, AND SUPPRESSING FUNCTION OF IMMUNE-PROTECTIVE CELLS. CHRONIC INFLAMMATION IS A RISK FACTOR LINKED TO TC. THE ROLE OF AUTOIMMUNITY HAS BEEN A MATTER OF CONTROVERSY. HOWEVER, THERE IS EPIDEMIOLOGICAL CONNECTION BETWEEN AUTOIMMUNE THYROID DISEASE (AITD) AND TC; PATIENTS WITH AITD SHOW INCREASED INCIDENCE IN PAPILLARY THYROID CARCINOMA (PTC), AND THOSE WITH TC SHOW A HIGH PREVALENCE OF INTRATHYROIDAL LYMPHOCYTE INFILTRATION AND THYROID AUTOANTIBODIES. TIMING AND DURATION-DEPENDENT EXPOSURE TO SPECIFIC ENDOCRINE DISRUPTING CHEMICALS (EDCS) HAS AN IMPACT ON THYROID DEVELOPMENT, FUNCTION, AND PROLIFERATION, LEADING TO THYROID DISEASE AND POTENTIALLY CANCER. THYROID HORMONE IMBALANCE, CHRONIC INFLAMMATION, AND EDCS ARE POTENTIAL RISK FACTORS FOR OXIDATIVE STRESS. OXYGEN FREE RADICALS ARE CAPABLE OF CAUSING DNA DAMAGE VIA STIMULATION OF THE MITOGEN-ACTIVATING PROTEIN KINASE OR PHOSPHATIDYLINOSITOL-3-KINASE AND/OR NUCLEAR FACTOR KB PATHWAYS, RESULTING IN TC-ASSOCIATED GENE MUTATIONS SUCH AS RET/PTC, AKAP9-BRAF, NTRK1, RAASF, PIK3CA, AND PTEN. STRESSFUL EVENTS DURING THE CRITICAL PERIODS OF PRENATAL AND EARLY LIFE CAN INFLUENCE NEUROENDOCRINE REGULATION AND INDUCE EPIGENETIC CHANGES. ABERRANT METHYLATION OF TUMOR SUPPRESSOR GENES SUCH AS P16INK4A, RASSF, AND PTEN IS ASSOCIATED WITH PTC; HISTONE H3 ACETYLATION IS SHOWN TO BE HIGHER IN TC, AND THYROID-SPECIFIC NONCODING RNAS ARE DOWNREGULATED IN PTC. THIS REVIEW FOCUSES ON THE ABOVE PROPOSED MECHANISMS THAT POTENTIALLY LEAD TO THYROID TUMORIGENESIS WITH THE AIM TO HELP IN THE DEVELOPMENT OF NOVEL PROGNOSTIC AND THERAPEUTIC STRATEGIES FOR TC. 2023 11 114 24 A SOCIO-BIOLOGICAL EXPLANATION FOR SOCIAL DISPARITIES IN NON-COMMUNICABLE CHRONIC DISEASES: THE PRODUCT OF HISTORY? THIS STUDY PLACES SOCIAL DISPARITIES IN THE MAJOR NON-COMMUNICABLE CHRONIC DISEASES WITHIN THEIR GLOBAL ECONOMIC AND HISTORICAL CONTEXTS. RAPID ECONOMIC TRANSITION OUTSIDE THE DEVELOPED WORLD PROVIDES A UNIQUE OPPORTUNITY TO RE-EXAMINE THE ORIGINS OF, AND BIOLOGICAL MECHANISMS DRIVING, SOCIAL DISPARITIES. GAPS IN PREVAILING THEORIES FOCUSING ON MATERIAL RESOURCES, CIVIC INFRASTRUCTURE AND SOCIAL STRUCTURE ARE IDENTIFIED. USING LONGSTANDING EXPERIMENTAL EVIDENCE AND EPIGENETIC THEORIES, IT IS SUGGESTED THAT EXPOSURE TO ECONOMIC DEVELOPMENT OVER GENERATIONS (IE, IMPROVED LIVING CONDITIONS OVER HISTORICAL TIME) COULD BY ACTING ON DIFFERENT BIOLOGICAL AXES (SOMATOTROPHIC AND GONADOTROPHIC) GENERATE SPECIFIC PATTERNS OF SOCIAL DISPARITIES. MOREOVER, THESE SAME PROCESSES COULD INITIALLY GENERATE A TRANSIENT EPIDEMIC OF DIABETES AS WELL AS A PERMANENT INCREASE IN MALE RISK OF PREMATURE ISCHAEMIC HEART DISEASE. AS SUCH, THIS STUDY DEMONSTRATES THE IMPORTANCE OF CONTEXT, AND IMPLIES THAT CURRENT EVIDENCE FROM THE DEVELOPED WORLD MAY BE LARGELY UNINFORMATIVE FOR PREVENTING OR MITIGATING SOCIAL DISPARITIES IN NON-COMMUNICABLE CHRONIC DISEASES ELSEWHERE, SUGGESTING RESEARCH EFFORTS SHOULD BE FOCUSED ON DEVELOPING COUNTRIES. 2010 12 3405 38 HOW STRESS GETS UNDER THE SKIN: EARLY LIFE ADVERSITY AND GLUCOCORTICOID RECEPTOR EPIGENETIC REGULATION. EARLY LIFE ADVERSITY IS ASSOCIATED WITH BOTH PERSISTENT DISRUPTIONS IN THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS AND PSYCHIATRIC SYMPTOMS. GLUCOCORTICOID RECEPTORS (GRS), WHICH ARE ENCODED BY THE NR3C1 GENE, BIND TO CORTISOL AND OTHER GLUCOCORTICOIDS TO CREATE A NEGATIVE FEEDBACK LOOP WITHIN THE HPA AXIS TO REGULATE THE BODY'S NEUROENDOCRINE RESPONSE TO STRESS. EXCESS METHYLATION OF A PROMOTER SEQUENCE WITHIN NR3C1 THAT ATTENUATES GR EXPRESSION, HOWEVER, HAS BEEN ASSOCIATED WITH BOTH EARLY LIFE ADVERSITY AND PSYCHOPATHOLOGY. AS CRITICAL REGULATORS WITHIN THE HPA AXIS, GRS AND THEIR EPIGENETIC REGULATION MAY MEDIATE THE LINK BETWEEN EARLY LIFE ADVERSITY AND THE ONSET OF PSYCHOPATHOLOGY. THE PRESENT REVIEW DISCUSSES THIS WORK AS ONE MECHANISM BY WHICH STRESS MAY GET UNDER THE SKIN TO DISRUPT HPA FUNCTIONING AT AN EPIGENETIC LEVEL AND CREATE LONG-LASTING VULNERABILITIES IN THE STRESS REGULATORY SYSTEM THAT SUBSEQUENTLY PREDISPOSE INDIVIDUALS TO PSYCHOPATHOLOGY. SPANNING PRENATAL INFLUENCES TO CRITICAL PERIODS OF EARLY LIFE AND ADOLESCENCE, WE DETAIL THE IMPACT THAT EARLY ADVERSITY HAS ON GR EXPRESSION, PHYSIOLOGICAL RESPONSES TO STRESS, AND THEIR IMPLICATIONS FOR LONG-TERM STRESS MANAGEMENT. WE NEXT PROPOSE A DUAL TRANSMISSION HYPOTHESIS REGARDING BOTH GENOMIC AND NON-GENOMIC MECHANISMS BY WHICH CHRONIC AND ACUTE STRESS PROPAGATE THROUGH NUMEROUS GENERATIONS. LASTLY, WE OUTLINE SEVERAL DIRECTIONS FOR FUTURE RESEARCH, INCLUDING POTENTIAL REVERSIBILITY OF METHYLATION PATTERNS AND ITS FUNCTIONAL IMPLICATIONS, VARIATION IN BEHAVIOR DETERMINED SOLELY BY NR3C1, AND CONSENSUS ON WHICH SPECIFIC PROMOTER REGIONS SHOULD BE STUDIED. 2018 13 3092 39 GENOMIC AND EPIGENOMIC MECHANISMS OF GLUCOCORTICOIDS IN THE BRAIN. FOLLOWING THE DISCOVERY OF GLUCOCORTICOID RECEPTORS IN THE HIPPOCAMPUS AND OTHER BRAIN REGIONS, RESEARCH HAS FOCUSED ON UNDERSTANDING THE EFFECTS OF GLUCOCORTICOIDS IN THE BRAIN AND THEIR ROLE IN REGULATING EMOTION AND COGNITION. GLUCOCORTICOIDS ARE ESSENTIAL FOR ADAPTATION TO STRESSORS (ALLOSTASIS) AND IN MALADAPTATION RESULTING FROM ALLOSTATIC LOAD AND OVERLOAD. ALLOSTATIC OVERLOAD, WHICH CAN OCCUR DURING CHRONIC STRESS, CAN RESHAPE THE HYPOTHALAMIC-PITUITARY-ADRENAL AXIS THROUGH EPIGENETIC MODIFICATION OF GENES IN THE HIPPOCAMPUS, HYPOTHALAMUS AND OTHER STRESS-RESPONSIVE BRAIN REGIONS. GLUCOCORTICOIDS EXERT THEIR EFFECTS ON THE BRAIN THROUGH GENOMIC MECHANISMS THAT INVOLVE BOTH GLUCOCORTICOID RECEPTORS AND MINERALOCORTICOID RECEPTORS DIRECTLY BINDING TO DNA, AS WELL AS BY NON-GENOMIC MECHANISMS. FURTHERMORE, GLUCOCORTICOIDS SYNERGIZE BOTH GENOMICALLY AND NON-GENOMICALLY WITH NEUROTRANSMITTERS, NEUROTROPHIC FACTORS, SEX HORMONES AND OTHER STRESS MEDIATORS TO SHAPE AN ORGANISM'S PRESENT AND FUTURE RESPONSES TO A STRESSFUL ENVIRONMENT. HERE, WE DISCUSS THE MECHANISMS OF GLUCOCORTICOID ACTION IN THE BRAIN AND REVIEW HOW GLUCOCORTICOIDS INTERACT WITH STRESS MEDIATORS IN THE CONTEXT OF ALLOSTASIS, ALLOSTATIC LOAD AND STRESS-INDUCED NEUROPLASTICITY. 2017 14 4909 35 PAIN AND STRESS IN A SYSTEMS PERSPECTIVE: RECIPROCAL NEURAL, ENDOCRINE, AND IMMUNE INTERACTIONS. THIS PAPER ADVANCES A PSYCHOPHYSIOLOGICAL SYSTEMS VIEW OF PAIN IN WHICH PHYSICAL INJURY, OR WOUNDING, GENERATES A COMPLEX STRESS RESPONSE THAT EXTENDS BEYOND THE NERVOUS SYSTEM AND CONTRIBUTES TO THE EXPERIENCE OF PAIN. THROUGH A COMMON CHEMICAL LANGUAGE COMPRISING NEUROTRANSMITTERS, PEPTIDES, ENDOCANNABINOIDS, CYTOKINES, AND HORMONES, AN ENSEMBLE OF INTERDEPENDENT NERVOUS, ENDOCRINE, AND IMMUNE PROCESSES OPERATES IN CONCERT TO COPE WITH THE INJURY. THESE PROCESSES ACT AS A SINGLE AGENT AND COMPRISE A SUPERSYSTEM. ACUTE PAIN IN ITS MULTIPLE DIMENSIONS, AND THE RELATED SYMPTOMS THAT COMMONLY OCCUR WITH IT, ARE PRODUCTS OF THE SUPERSYSTEM. CHRONIC PAIN CAN DEVELOP AS A RESULT OF UNUSUAL STRESS. SOCIAL STRESSORS CAN COMPOUND THE STRESS RESULTING FROM A WOUND OR ACT ALONE TO DYSREGULATE THE SUPERSYSTEM. WHEN THE SUPERSYSTEM SUFFERS DYSREGULATION, HEALTH, FUNCTION, AND SENSE OF WELL-BEING SUFFER. SOME CHRONIC PAIN CONDITIONS ARE THE PRODUCT OF SUPERSYSTEM DYSREGULATION. INDIVIDUALS VARY AND ARE VULNERABLE TO DYSREGULATION AND DYSFUNCTION IN PARTICULAR ORGAN SYSTEMS DUE TO THE UNIQUE INTERACTIONS OF GENETIC, EPIGENETIC AND ENVIRONMENTAL FACTORS, AS WELL AS THE PAST EXPERIENCES THAT CHARACTERIZE EACH PERSON. PERSPECTIVE: ACUTE TISSUE INJURY ACTIVATES AN ENSEMBLE OF INTERDEPENDENT NERVOUS, ENDOCRINE, AND IMMUNE PROCESSES THAT OPERATE IN CONCERT AND COMPRISE A SUPERSYSTEM. SOME CHRONIC PAIN CONDITIONS RESULT FROM SUPERSYSTEM DYSREGULATION. INDIVIDUALS VARY AND ARE VULNERABLE TO DYSREGULATION DUE TO THE UNIQUE INTERACTIONS OF GENETIC, EPIGENETIC, AND ENVIRONMENTAL FACTORS AND PAST EXPERIENCES THAT CHARACTERIZE EACH PERSON. THIS PERSPECTIVE CAN POTENTIALLY ASSIST CLINICIANS IN ASSESSING AND MANAGING CHRONIC PAIN PATIENTS. 2008 15 23 36 60 YEARS OF NEUROENDOCRINOLOGY: REDEFINING NEUROENDOCRINOLOGY: STRESS, SEX AND COGNITIVE AND EMOTIONAL REGULATION. THE DISCOVERY OF STEROID HORMONE RECEPTORS IN BRAIN REGIONS THAT MEDIATE EVERY ASPECT OF BRAIN FUNCTION HAS BROADENED THE DEFINITION OF 'NEUROENDOCRINOLOGY' TO INCLUDE THE RECIPROCAL COMMUNICATION BETWEEN THE BRAIN AND THE BODY VIA HORMONAL AND NEURAL PATHWAYS. THE BRAIN IS THE CENTRAL ORGAN OF STRESS AND ADAPTATION TO STRESS BECAUSE IT PERCEIVES AND DETERMINES WHAT IS THREATENING, AS WELL AS THE BEHAVIORAL AND PHYSIOLOGICAL RESPONSES TO THE STRESSOR. THE ADULT AND DEVELOPING BRAIN POSSESS REMARKABLE STRUCTURAL AND FUNCTIONAL PLASTICITY IN RESPONSE TO STRESS, INCLUDING NEURONAL REPLACEMENT, DENDRITIC REMODELING, AND SYNAPSE TURNOVER. STRESS CAUSES AN IMBALANCE OF NEURAL CIRCUITRY SUBSERVING COGNITION, DECISION-MAKING, ANXIETY AND MOOD THAT CAN ALTER EXPRESSION OF THOSE BEHAVIORS AND BEHAVIORAL STATES. THIS IMBALANCE, IN TURN, AFFECTS SYSTEMIC PHYSIOLOGY VIA NEUROENDOCRINE, AUTONOMIC, IMMUNE AND METABOLIC MEDIATORS. IN THE SHORT TERM, AS FOR INCREASED FEARFUL VIGILANCE AND ANXIETY IN A THREATENING ENVIRONMENT, THESE CHANGES MAY BE ADAPTIVE. BUT, IF THE DANGER PASSES AND THE BEHAVIORAL STATE PERSISTS ALONG WITH THE CHANGES IN NEURAL CIRCUITRY, SUCH MALADAPTATION MAY NEED INTERVENTION WITH A COMBINATION OF PHARMACOLOGICAL AND BEHAVIORAL THERAPIES, AS IS THE CASE FOR CHRONIC ANXIETY AND DEPRESSION. THERE ARE IMPORTANT SEX DIFFERENCES IN THE BRAIN RESPONSES TO STRESSORS THAT ARE IN URGENT NEED OF FURTHER EXPLORATION. MOREOVER, ADVERSE EARLY-LIFE EXPERIENCE, INTERACTING WITH ALLELES OF CERTAIN GENES, PRODUCE LASTING EFFECTS ON BRAIN AND BODY OVER THE LIFE-COURSE VIA EPIGENETIC MECHANISMS. WHILE PREVENTION IS MOST IMPORTANT, THE PLASTICITY OF THE BRAIN GIVES HOPE FOR THERAPIES THAT TAKE INTO CONSIDERATION BRAIN-BODY INTERACTIONS. 2015 16 4622 30 NEUROBIOLOGICAL DEVELOPMENT IN THE CONTEXT OF CHILDHOOD TRAUMA. NEUROBIOLOGICAL SYSTEMS MAY BE PARTICULARLY SUSCEPTIBLE TO DELETERIOUS IMPACT OF CHILDHOOD TRAUMA, AND THE IMPACT OF CHILDHOOD TRAUMA ON DEVELOPMENT AND SUBSEQUENT FUNCTIONAL OUTCOMES ACROSS THE LIFESPAN HAS BEEN WELL-DOCUMENTED. THE CURRENT REVIEW ADDRESSES THE NEUROBIOLOGICAL IMPACT OF EXPOSURE TO INTERPERSONAL TRAUMA IN CHILDHOOD IN THE CONTEXT OF EXECUTIVE FUNCTION, EMOTION REGULATION, AND DISSOCIATION/INTEROCEPTIVE AWARENESS. SUBSEQUENT RISK FOR PTSD AND DEPRESSION IS ALSO DISCUSSED. THE PATHWAY OF RISK FROM CHILDHOOD TRAUMA TO THESE COGNITIVE, EMOTIONAL, AND PSYCHIATRIC OUTCOMES IS ADDRESSED IN TERMS OF POTENTIAL STRUCTURAL AND FUNCTIONAL ALTERATIONS WITHIN THE HIPPOCAMPUS, PREFRONTAL CORTEX, AND AMYGDALA RESULTING FROM CHRONIC OR REPEATED ACTIVATION OF THE HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS AND ITS INTERACTION WITH AND INFLUENCE ON GENETIC AND EPIGENETIC PROCESSES DURING SENSITIVE PERIODS OF DEVELOPMENT. IMPLICATIONS FOR PRACTICE ARE DISCUSSED. 2017 17 5197 30 PRENATAL GLUCOCORTICOIDS EXPOSURE AND FETAL ADRENAL DEVELOPMENTAL PROGRAMMING. CLINICALLY, WE APPLY SYNTHETIC GLUCOCORTICOIDS TO TREAT FETAL AND MATERNAL DISEASES, SUCH AS PREMATURE LABOR AND AUTOIMMUNE DISEASES. ALTHOUGH ITS CLINICAL EFFICACY IS POSITIVE, THE FETUS WILL BE EXPOSED TO EXOGENOUS SYNTHETIC GLUCOCORTICOIDS. PRENATAL ADVERSE ENVIRONMENTS (SUCH AS XENOBIOTICS EXPOSURE, MALNUTRITION, INFECTION, HYPOXIA AND STRESS) CAN CAUSE FETUSES OVEREXPOSURE TO EXCESSIVE ENDOGENOUS MATERNAL GLUCOCORTICOIDS. THE LEVEL OF GLUCOCORTICOIDS IS THE KEY TO FETAL TISSUE MATURATION AND POSTNATAL FATE. A LARGE NUMBER OF STUDIES HAVE FOUND THAT PRENATAL GLUCOCORTICOIDS EXPOSURE CAN LEAD TO FETAL ADRENAL DYSPLASIA AND DYSFUNCTION, CONTINUING AFTER BIRTH AND EVEN INTO ADULTHOOD. AS THE CORE ORGAN OF FETAL-ORIGINATED ADULT DISEASES, FETAL ADRENAL DYSPLASIA IS CLOSELY RELATED TO THE SUSCEPTIBILITY AND OCCURRENCE OF MULTIPLE CHRONIC DISEASES, AND THERE ARE ALSO OBVIOUS GENDER DIFFERENCES. HOWEVER, ITS INTRAUTERINE PROGRAMMING MECHANISMS HAVE NOT BEEN FULLY ELUCIDATED. THIS REVIEW SUMMARIZES RECENT ADVANCES IN PRENATAL GLUCOCORTICOIDS EXPOSURE AND FETAL ADRENAL DEVELOPMENTAL PROGRAMMING ALTERATIONS, WHICH IS OF GREAT SIGNIFICANCE FOR EXPLAINING ADRENAL DEVELOPMENTAL TOXICITY AND THE INTRAUTERINE ORIGIN OF FETAL-ORIGINATED ADULT DISEASES. 2019 18 1754 40 EARLY LIFE STRESS, THE DEVELOPMENT OF AGGRESSION AND NEUROENDOCRINE AND NEUROBIOLOGICAL CORRELATES: WHAT CAN WE LEARN FROM ANIMAL MODELS? EARLY LIFE STRESS (CHILD AND ADOLESCENT ABUSE, NEGLECT AND TRAUMA) INDUCES ROBUST ALTERATIONS IN EMOTIONAL AND SOCIAL FUNCTIONING RESULTING IN ENHANCED RISK FOR THE DEVELOPMENT OF PSYCHOPATHOLOGIES SUCH AS MOOD AND AGGRESSIVE DISORDERS. HERE, AN OVERVIEW IS GIVEN ON RECENT FINDINGS IN PRIMATE AND RODENT MODELS OF EARLY LIFE STRESS, DEMONSTRATING THAT CHRONIC DEPRIVATION OF EARLY MATERNAL CARE AS WELL AS CHRONIC DEPRIVATION OF EARLY PHYSICAL INTERACTIONS WITH PEERS ARE PROFOUND RISK FACTORS FOR THE DEVELOPMENT OF INAPPROPRIATE AGGRESSIVE BEHAVIORS. ALTERATIONS IN THE HYPOTHALAMIC-PITUITARY-ADRENOCORTICAL (HPA), VASOPRESSIN AND SEROTONIN SYSTEMS AND THEIR RELEVANCE FOR THE REGULATION OF AGGRESSION ARE DISCUSSED. DATA SUGGEST THAT SOCIAL DEPRIVATION-INDUCED INAPPROPRIATE FORMS OF AGGRESSION ARE ASSOCIATED WITH HIGH OR LOW HPA AXIS (RE)ACTIVITY AND A GENERALLY LOWER FUNCTIONING OF THE SEROTONIN SYSTEM IN ADULTHOOD. MOREOVER, GENETIC AND EPIGENETIC MODIFICATIONS IN HPA AND SEROTONIN SYSTEMS INFLUENCE THE OUTCOME OF EARLY LIFE STRESS AND MAY EVEN MODERATE ADVERSE EFFECTS OF EARLY SOCIAL DEPRIVATION ON AGGRESSION. A MORE COMPREHENSIVE STUDY OF AGGRESSION, NEUROENDOCRINE, NEUROBIOLOGICAL AND (EPI)GENETIC CORRELATES OF EARLY LIFE STRESS USING ANIMAL MODELS IS NECESSARY TO PROVIDE A BETTER UNDERSTANDING OF THE INVASIVE AGGRESSIVE DEFICITS OBSERVED IN HUMANS EXPOSED TO CHILD MALTREATMENT. 2009 19 1750 27 EARLY LIFE STRESS AND PEDIATRIC POSTTRAUMATIC STRESS DISORDER. TRAUMATIC STRESS EXPOSURE DURING CRITICAL PERIODS OF DEVELOPMENT MAY HAVE ESSENTIAL AND LONG-LASTING EFFECTS ON THE PHYSICAL AND MENTAL HEALTH OF INDIVIDUALS. TWO THIRDS OF YOUTH ARE EXPOSED TO POTENTIALLY TRAUMATIC EXPERIENCES BY THE AGE OF 17, AND APPROXIMATELY 5% OF ADOLESCENTS MEET LIFETIME CRITERIA FOR POSTTRAUMATIC STRESS DISORDER (PTSD). THE ROLE OF THE STRESS SYSTEM IS THE MAINTENANCE OF HOMEOSTASIS IN THE PRESENCE OF REAL/PERCEIVED AND ACUTE/CHRONIC STRESSORS. EARLY-LIFE STRESS (ELS) HAS AN IMPACT ON NEURONAL BRAIN NETWORKS INVOLVED IN STRESS REACTIONS, AND COULD EXERT A PROGRAMMING EFFECT ON GLUCOCORTICOID SIGNALING. STUDIES ON PEDIATRIC PTSD REVEAL DIVERSE NEUROENDOCRINE RESPONSES TO ADVERSE EVENTS AND RELATED LONG-TERM NEUROENDOCRINE AND EPIGENETIC ALTERATIONS. NEUROENDOCRINE, NEUROIMAGING, AND GENETIC STUDIES IN CHILDREN WITH PTSD AND ELS EXPERIENCES ARE CRUCIAL IN UNDERSTANDING RISK AND RESILIENCE FACTORS, AND ALSO THE NATURAL HISTORY OF PTSD. 2020 20 6026 35 THE BIOLOGY OF STRESS INTOLERANCE IN PATIENTS WITH CHRONIC PAIN-STATE OF THE ART AND FUTURE DIRECTIONS. STRESS HAS BEEN CONSISTENTLY LINKED TO NEGATIVE IMPACTS ON PHYSICAL AND MENTAL HEALTH. MORE SPECIFICALLY, PATIENTS WITH CHRONIC PAIN EXPERIENCE STRESS INTOLERANCE, WHICH IS AN EXACERBATION OR OCCURRENCE OF SYMPTOMS IN RESPONSE TO ANY TYPE OF STRESS. THE PATHOPHYSIOLOGICAL MECHANISMS UNDERLYING THIS PHENOMENON REMAIN UNSOLVED. IN THIS STATE-OF-THE-ART PAPER, WE SUMMARISED THE ROLE OF THE AUTONOMIC NERVOUS SYSTEM (ANS) AND HYPOTHALAMUS-PITUITARY-ADRENAL (HPA) AXIS, THE TWO MAJOR STRESS RESPONSE SYSTEMS IN STRESS INTOLERANCE. WE PROVIDED INSIGHTS INTO SUCH MECHANISMS BASED ON EVIDENCE FROM CLINICAL STUDIES IN BOTH PATIENTS WITH CHRONIC PAIN, SHOWING DYSREGULATED STRESS SYSTEMS, AND HEALTHY CONTROLS SUPPORTED BY PRECLINICAL STUDIES, HIGHLIGHTING THE LINK BETWEEN THESE SYSTEMS AND SYMPTOMS OF STRESS INTOLERANCE. FURTHERMORE, WE EXPLORED THE POSSIBLE REGULATING ROLE FOR (EPI)GENETIC MECHANISMS INFLUENCING THE ANS AND HPA AXIS. THE LINK BETWEEN STRESS AND CHRONIC PAIN HAS BECOME AN IMPORTANT AREA OF RESEARCH AS IT HAS THE POTENTIAL TO INFORM THE DEVELOPMENT OF INTERVENTIONS TO IMPROVE THE QUALITY OF LIFE FOR INDIVIDUALS LIVING WITH CHRONIC PAIN. AS STRESS HAS BECOME A PREVALENT CONCERN IN MODERN SOCIETY, UNDERSTANDING THE CONNECTION BETWEEN STRESS, HPA AXIS, ANS, AND CHRONIC HEALTH CONDITIONS SUCH AS CHRONIC PAIN IS CRUCIAL TO IMPROVE PUBLIC HEALTH AND WELL-BEING. 2023