1 231 116 ADAPTIVE CARDIORESPIRATORY CHANGES TO CHRONIC CONTINUOUS AND INTERMITTENT HYPOXIA. THIS CHAPTER REVIEWS CARDIORESPIRATORY ADAPTATIONS TO CHRONIC HYPOXIA (CH) EXPERIENCED AT HIGH ALTITUDE AND CARDIORESPIRATORY PATHOLOGIES ELICITED BY CHRONIC INTERMITTENT HYPOXIA (CIH) OCCURRING WITH OBSTRUCTIVE SLEEP APNEA (OSA). SHORT-TERM CH INCREASES BREATHING (VENTILATORY ACCLIMATIZATION TO HYPOXIA) AND BLOOD PRESSURE (BP) THROUGH CAROTID BODY (CB) CHEMO REFLEX. HYPERPLASIA OF GLOMUS CELLS, ALTERATIONS IN ION CHANNELS, AND RECRUITMENT OF ADDITIONAL EXCITATORY MOLECULES ARE IMPLICATED IN THE HEIGHTENED CB CHEMO REFLEX BY CH. TRANSCRIPTIONAL ACTIVATION OF HYPOXIA-INDUCIBLE FACTORS (HIF-1 AND 2) IS A MAJOR MOLECULAR MECHANISM UNDERLYING RESPIRATORY ADAPTATIONS TO SHORT-TERM CH. HIGH-ALTITUDE NATIVES EXPERIENCING LONG-TERM CH EXHIBIT BLUNTED HYPOXIC VENTILATORY RESPONSE (HVR) AND REDUCED BP DUE TO DESENSITIZATION OF CB RESPONSE TO HYPOXIA AND IMPAIRED PROCESSING OF CB SENSORY INFORMATION AT THE CENTRAL NERVOUS SYSTEM. VENTILATORY CHANGES EVOKED BY LONG-TERM CH ARE NOT READILY REVERSED AFTER RETURN TO SEA LEVEL. OSA PATIENTS AND RODENTS SUBJECTED TO CIH EXHIBIT HEIGHTENED CB CHEMO REFLEX, INCREASED HYPOXIC VENTILATORY RESPONSE, AND HYPERTENSION. INCREASED GENERATION OF REACTIVE OXYGEN SPECIES (ROS) IS A MAJOR CELLULAR MECHANISM UNDERLYING CIH-INDUCED ENHANCED CB CHEMO REFLEX AND THE ENSUING CARDIORESPIRATORY PATHOLOGIES. ROS GENERATION BY CIH IS MEDIATED BY NONTRANSCRIPTIONAL, DISRUPTED HIF-1 AND HIF-2-DEPENDENT TRANSCRIPTIONS AS WELL AS EPIGENETIC MECHANISMS. 2022 2 444 24 AORTIC AND CAROTID ARTERIAL STIFFNESS AND EPIGENETIC REGULATOR GENE EXPRESSION CHANGES PRECEDE BLOOD PRESSURE RISE IN STROKE-PRONE DAHL SALT-SENSITIVE HYPERTENSIVE RATS. MULTIPLE CLINICAL STUDIES SHOW THAT ARTERIAL STIFFNESS, MEASURED AS PULSE WAVE VELOCITY (PWV), PRECEDES HYPERTENSION AND IS AN INDEPENDENT PREDICTOR OF HYPERTENSION END ORGAN DISEASES INCLUDING STROKE, CARDIOVASCULAR DISEASE AND CHRONIC KIDNEY DISEASE. RISK FACTOR STUDIES FOR ARTERIAL STIFFNESS IMPLICATE AGE, HYPERTENSION AND SODIUM. HOWEVER, CAUSAL MECHANISMS LINKING RISK FACTOR TO ARTERIAL STIFFNESS REMAIN TO BE ELUCIDATED. HERE, WE STUDIED THE CAUSAL RELATIONSHIP OF ARTERIAL STIFFNESS AND HYPERTENSION IN THE NA-INDUCED, STROKE-PRONE DAHL SALT-SENSITIVE (S) HYPERTENSIVE RAT MODEL, AND ANALYZED PUTATIVE MOLECULAR MECHANISMS. STROKE-PRONE AND NON-STROKE-PRONE MALE AND FEMALE RATS WERE STUDIED AT 3- AND 6-WEEKS OF AGE FOR ARTERIAL STIFFNESS (PWV, STRAIN), BLOOD PRESSURE, VESSEL WALL HISTOLOGY, AND GENE EXPRESSION CHANGES. STUDIES SHOWED THAT INCREASED LEFT CAROTID AND AORTIC ARTERIAL STIFFNESS PRECEDED HYPERTENSION, PULSE PRESSURE WIDENING, AND STRUCTURAL WALL CHANGES AT THE 6-WEEK TIME-POINT. INSTEAD, DIFFERENTIAL GENE INDUCTION WAS DETECTED IMPLICATING MOLECULAR-FUNCTIONAL CHANGES IN EXTRACELLULAR MATRIX (ECM) STRUCTURAL CONSTITUENTS, MODIFIERS, CELL ADHESION, AND MATRICELLULAR PROTEINS, AS WELL AS IN ENDOTHELIAL FUNCTION, APOPTOSIS BALANCE, AND EPIGENETIC REGULATORS. IMMUNOSTAINING TESTING HISTONE MODIFIERS EP300, HDAC3, AND PRMT5 LEVELS CONFIRMED CAROTID ARTERY-UPREGULATION IN ALL THREE LAYERS: ENDOTHELIAL, SMOOTH MUSCLE AND ADVENTITIAL CELLS. OUR STUDY RECAPITULATES OBSERVATIONS IN HUMANS THAT GIVEN SALT-SENSITIVITY, INCREASED NA-INTAKE INDUCED ARTERIAL STIFFNESS BEFORE HYPERTENSION, INCREASED PULSE PRESSURE, AND STRUCTURAL VESSEL WALL CHANGES. DIFFERENTIAL GENE EXPRESSION CHANGES ASSOCIATED WITH ARTERIAL STIFFNESS SUGGEST A MOLECULAR MECHANISM LINKING SODIUM TO FULL-VESSEL WALL RESPONSE AFFECTING GENE-NETWORKS INVOLVED IN VASCULAR ECM STRUCTURE-FUNCTION, APOPTOSIS BALANCE, AND EPIGENETIC REGULATION. 2014 3 5124 21 POST-OCCLUSION ADMINISTRATION OF SODIUM BUTYRATE ATTENUATES COGNITIVE IMPAIRMENT IN A RAT MODEL OF CHRONIC CEREBRAL HYPOPERFUSION. CHRONIC CEREBRAL HYPOPERFUSION (CCH) HAS BEEN COMMONLY ASSOCIATED WITH ALZHEIMER'S DISEASE AND OTHER TYPES OF DEMENTIA, BUT THERAPIES THAT CAN IMPROVE CEREBRAL BLOOD FLOW DISPLAYED LITTLE EFFECT ON IMPAIRED COGNITION. EPIGENETIC INTERVENTION WITH HISTONE DEACETYLASE INHIBITORS, SUCH AS SODIUM BUTYRATE (SB), ON THE OTHER HAND HAS BEEN SHOWN TO IMPROVE COGNITION IN SEVERAL ANIMAL MODELS OF DEMENTIA. TO INVESTIGATE THE EFFECT OF SB ON COGNITIVE IMPAIRMENT INDUCED BY CCH IN RATS, ADULT MALE SD RATS WERE GIVEN INTRAPERITONEAL INJECTIONS OF SB AT A DAILY DOSE OF 840MG/KG FOR 4WEEKS, FROM THE 29TH DAY AFTER PERMANENT OCCLUSION OF BILATERAL COMMON CAROTID ARTERIES (2VO). LEARNING AND MEMORY WERE ASSESSED BY MORRIS WATER MAZE AND NOVEL OBJECT RECOGNITION. FOLLOWING BEHAVIORAL TESTS, WESTERN BLOTTING OF HISTONE ACETYLATION, OF TRANSCRIPTION FACTORS, OF NEURONAL/SYNAPTIC PROTEINS, WERE PERFORMED USING RAT HIPPOCAMPUS AND CORTEX. THE DATA SHOWED THAT SB TREATMENT ALLEVIATED HIPPOCAMPAL DEPENDENT SPATIAL LEARNING DISABILITY IN 2VO RATS, AND ALTERED HDAC1/2 MRNA LEVEL, HISTONE H4 ACETYLATION AND NRF2 TRANSCRIPTIONAL ACTIVATION IN RAT HIPPOCAMPUS. ACCORDINGLY, COGNITION-PROTECTIVE EFFECT OF SB APPEARED TO BE PARTIALLY MEDIATED BY ENHANCING HISTONE ACETYLATION AND HENCE BY FACILITATING THE TRANSCRIPTION OF NRF2 DOWNSTREAM GENES IN THE HIPPOCAMPUS. THUS, SB MIGHT BE CONSIDERED FOR PUTATIVE TREATMENT FOR CCH-RELATED COGNITIVE IMPAIRMENT. 2015 4 4197 25 METABOLIC PROFILES IN OVINE CAROTID ARTERIES WITH DEVELOPMENTAL MATURATION AND LONG-TERM HYPOXIA. BACKGROUND: LONG-TERM HYPOXIA (LTH) IS AN IMPORTANT STRESSOR RELATED TO HEALTH AND DISEASE DURING DEVELOPMENT. AT DIFFERENT TIME POINTS FROM FETUS TO ADULT, WE ARE EXPOSED TO HYPOXIC STRESS BECAUSE OF PLACENTAL INSUFFICIENCY, HIGH-ALTITUDE RESIDENCE, SMOKING, CHRONIC ANEMIA, PULMONARY, AND HEART DISORDERS, AS WELL AS CANCERS. INTRAUTERINE HYPOXIA CAN LEAD TO FETAL GROWTH RESTRICTION AND LONG-TERM SEQUELAE SUCH AS COGNITIVE IMPAIRMENTS, HYPERTENSION, CARDIOVASCULAR DISORDERS, DIABETES, AND SCHIZOPHRENIA. SIMILARLY, PROLONGED HYPOXIC EXPOSURE DURING ADULT LIFE CAN LEAD TO ACUTE MOUNTAIN SICKNESS, CHRONIC FATIGUE, CHRONIC HEADACHE, COGNITIVE IMPAIRMENT, ACUTE CEREBRAL AND/OR PULMONARY EDEMA, AND DEATH. AIM: LTH ALSO CAN LEAD TO ALTERATION IN METABOLITES SUCH AS FUMARATE, 2-OXOGLUTARATE, MALATE, AND LACTATE, WHICH ARE LINKED TO EPIGENETIC REGULATION OF GENE EXPRESSION. IMPORTANTLY, DURING THE INTRAUTERINE LIFE, A FETUS IS UNDER A RELATIVE HYPOXIC ENVIRONMENT, AS COMPARED TO NEWBORN OR ADULT. THUS, THE CHANGES IN GENE EXPRESSION WITH DEVELOPMENT FROM FETUS TO NEWBORN TO ADULT MAY BE AS A CONSEQUENCE OF UNDERLYING CHANGES IN THE METABOLIC PROFILE BECAUSE OF THE HYPOXIC ENVIRONMENT ALONG WITH DEVELOPMENTAL MATURATION. TO EXAMINE THIS POSSIBILITY, WE EXAMINED THE METABOLIC PROFILE IN CAROTID ARTERIES FROM NEAR-TERM FETUS, NEWBORN, AND ADULT SHEEP IN BOTH NORMOXIC AND LONG-TERM HYPOXIC ACCLIMATIZED GROUPS. RESULTS: OUR RESULTS DEMONSTRATE THAT LTH DIFFERENTIALLY REGULATED GLUCOSE METABOLISM, MITOCHONDRIAL METABOLISM, NICOTINAMIDE COFACTOR METABOLISM, OXIDATIVE STRESS AND ANTIOXIDANTS, MEMBRANE LIPID HYDROLYSIS, AND FREE FATTY ACID METABOLISM, EACH OF WHICH MAY PLAY A ROLE IN GENETIC-EPIGENETIC REGULATION. 2015 5 2359 48 EPIGENETIC REGULATION OF REDOX STATE MEDIATES PERSISTENT CARDIORESPIRATORY ABNORMALITIES AFTER LONG-TERM INTERMITTENT HYPOXIA. KEY POINTS: THE EFFECTS OF SHORT-TERM (ST; 10 DAYS) AND LONG-TERM (LT; 30 DAYS) INTERMITTENT HYPOXIA (IH) ON BLOOD PRESSURE (BP), BREATHING AND CAROTID BODY (CB) CHEMOSENSORY REFLEX WERE EXAMINED IN ADULT RATS. ST- AND LT-IH TREATED RATS EXHIBITED HYPERTENSION, IRREGULAR BREATHING WITH APNOEA AND AUGMENTED THE CB CHEMOSENSORY REFLEX, WITH ALL THESE RESPONSES BECOMING NORMALIZED DURING RECOVERY FROM ST- BUT NOT FROM LT-IH. THE PERSISTENT CARDIORESPIRATORY RESPONSES TO LT-IH WERE ASSOCIATED WITH ELEVATED REACTIVE OXYGEN SPECIES (ROS) LEVELS IN THE CB AND ADRENAL MEDULLA, WHICH WERE A RESULT OF DNA METHYLATION-DEPENDENT SUPPRESSION OF GENES ENCODING ANTI-OXIDANT ENZYMES (AOES). TREATING RATS WITH DECITABINE EITHER DURING LT-IH OR DURING RECOVERY FROM LT-IH PREVENTED DNA METHYLATION OF AOE GENES, NORMALIZED THE EXPRESSION OF AOE GENES AND ROS LEVELS, REVERSED THE HEIGHTENED CB CHEMOSENSORY REFLEX AND HYPERTENSION, AND ALSO STABILIZED BREATHING. ABSTRACT: RODENTS EXPOSED TO CHRONIC INTERMITTENT HYPOXIA (IH), SIMULATING BLOOD O(2) SATURATION PROFILES DURING OBSTRUCTIVE SLEEP APNOEA (OSA), HAVE BEEN SHOWN TO EXHIBIT A HEIGHTENED CAROTID BODY (CB) CHEMOSENSORY REFLEX AND HYPERTENSION. CB CHEMOSENSORY REFLEX ACTIVATION ALSO RESULTS IN UNSTABLE BREATHING WITH APNOEAS. HOWEVER, THE EFFECT OF CHRONIC IH ON BREATHING IS NOT KNOWN. IN THE PRESENT STUDY, WE EXAMINED THE EFFECTS OF CHRONIC IH ON BREATHING ALONG WITH BLOOD PRESSURE (BP) AND ASSESSED WHETHER THE AUTONOMIC RESPONSES ARE NORMALIZED AFTER RECOVERY FROM CHRONIC IH. STUDIES WERE PERFORMED ON ADULT, MALE, SPRAGUE-DAWLEY RATS EXPOSED TO EITHER SHORT-TERM (ST; 10 DAYS) OR LONG-TERM (LT, 30 DAYS) IH. RATS EXPOSED TO EITHER ST- OR LT-IH EXHIBITED HYPERTENSION, IRREGULAR BREATHING WITH APNOEAS, AN AUGMENTED CB CHEMOSENSORY REFLEX AS INDICATED BY ELEVATED CB NEURAL ACTIVITY AND PLASMA CATECHOLAMINE LEVELS, AND ELEVATED REACTIVE OXYGEN SPECIES (ROS) LEVELS IN THE CB AND ADRENAL MEDULLA (AM). ALL THESE EFFECTS WERE NORMALIZED AFTER RECOVERY FROM ST-IH BUT NOT FROM LT-IH. ANALYSIS OF THE MOLECULAR MECHANISMS UNDERLYING THE PERSISTENT EFFECTS OF LT-IH REVEALED INCREASED DNA METHYLATION OF GENES ENCODING ANTI-OXIDANT ENZYMES (AOES). TREATMENT WITH DECITABINE, A DNA METHYLATION INHIBITOR, EITHER DURING LT-IH OR DURING RECOVERY FROM LT-IH, PREVENTED DNA METHYLATION, NORMALIZED THE EXPRESSION OF AOE GENES, ROS LEVELS, CB CHEMOSENSORY REFLEX AND BP, AND ALSO STABILIZED BREATHING. THESE RESULTS SUGGEST THAT PERSISTENT CARDIORESPIRATORY ABNORMALITIES CAUSED BY LT-IH ARE MEDIATED BY EPIGENETIC RE-PROGRAMMING OF THE REDOX STATE IN THE CB CHEMOSENSORY REFLEX PATHWAY. 2017 6 6774 25 [AGE-RELATED VASCULAR CHANGES EXEMPLIFIED BY THE CAROTID ARTERY]. ONE OF THE MAIN RISK FACTORS FOR THE PRESENCE OF CAROTID STENOSIS AND CAROTID-RELATED STROKE IS AGE. THE AIM OF THIS REVIEW ARTICLE IS TO PRESENT THE CURRENT STATE OF KNOWLEDGE ON AGE-RELATED VASCULAR CHANGES USING CAROTID STENOSIS AS AN EXAMPLE.VASCULAR AGING (VASCULAR SENESCENCE) IS A DECREASE OF STRUCTURAL AND FUNCTIONAL PROPERTIES OF THE VESSEL WALL THAT TAKES PLACE ON DIFFERENT LEVELS. AT THE MULTICELLULAR LEVEL AN INCREASE IN VESSEL VOLUME AND DIAMETER AS WELL AS INTIMA MEDIA THICKNESS OCCURS WITH AGE MAINLY DUE TO ATHEROSCLEROTIC CHANGES IN THE VESSEL WALL. AT THE CELLULAR AND EXTRACELLULAR LEVELS THERE IS A DECREASE IN ELASTIN FIBERS, SMOOTH MUSCLE CELLS, AND TOTAL CELLULARITY, AN INCREASE IN LIPID, CHOLESTEROL, AND CALCIUM PHOSPHATE DEPOSITION AS WELL AS NEOVASCULARIZATION. THE CAUSES OF VASCULAR AGING AT THE MOLECULAR LEVEL INCLUDE, IN PARTICULAR OXIDATIVE STRESS, CHRONIC INFLAMMATORY RESPONSE, MITOCHONDRIAL DYSFUNCTION, EPIGENETIC CHANGES, DYSREGULATION OF THE EXPRESSION OF NON-CODING RNAS (NCRNAS), AND THE INCREASE IN SENESCENCE. AGE-RELATED LOSS OF TISSUE HEALING AND REPAIR CAPACITY MAKE PLAQUES MORE VULNERABLE AND, IN THE CASE OF THE CAROTID ARTERY, MORE SUSCEPTIBLE TO ISCHEMIC STROKE.INCREASING KNOWLEDGE OF THE INFLUENCE OF AGING ON THE EPIGENETICS AND NCRNAS IN ATHEROSCLEROTIC PLAQUES CAN IN THE FUTURE MORE ACCURATELY QUANTIFY INDIVIDUAL PATIENT RISK AND CONTRIBUTE TO THE DEVELOPMENT OF TARGETED THERAPEUTIC STRATEGIES; HOWEVER, FURTHER STUDIES ARE NEEDED IN THIS FIELD TO UNDERSTAND THE FULL EXTENT OF VASCULAR AGING AND ITS ASSOCIATED DISEASES SO THAT THESE CAN THEN BE SPECIFICALLY TARGETED. 2022 7 1177 34 CONTROL OF BREATHING AND THE CIRCULATION IN HIGH-ALTITUDE MAMMALS AND BIRDS. HYPOXIA IS AN UNREMITTING STRESSOR AT HIGH ALTITUDES THAT PLACES A PREMIUM ON OXYGEN TRANSPORT BY THE RESPIRATORY AND CARDIOVASCULAR SYSTEMS. PHENOTYPIC PLASTICITY AND GENOTYPIC ADAPTATION AT VARIOUS STEPS IN THE O2 CASCADE COULD HELP OFFSET THE EFFECTS OF HYPOXIA ON CELLULAR O2 SUPPLY IN HIGH-ALTITUDE NATIVES. IN THIS REVIEW, WE WILL DISCUSS THE UNIQUE MECHANISMS BY WHICH VENTILATION, CARDIAC OUTPUT, AND BLOOD FLOW ARE CONTROLLED IN HIGH-ALTITUDE MAMMALS AND BIRDS. ACCLIMATIZATION TO HIGH ALTITUDES LEADS TO SOME CHANGES IN RESPIRATORY AND CARDIOVASCULAR CONTROL THAT INCREASE O2 TRANSPORT IN HYPOXIA (E.G., VENTILATORY ACCLIMATIZATION TO HYPOXIA). HOWEVER, ACCLIMATIZATION OR DEVELOPMENT IN HYPOXIA CAN ALSO MODIFY CARDIORESPIRATORY CONTROL IN WAYS THAT ARE MALADAPTIVE FOR O2 TRANSPORT. HYPOXIA RESPONSES THAT AROSE AS SHORT-TERM SOLUTIONS TO O2 DEPRIVATION (E.G., PERIPHERAL VASOCONSTRICTION) OR REGIONAL VARIATION IN O2 LEVELS IN THE LUNGS (I.E., HYPOXIC PULMONARY VASOCONSTRICTION) ARE DETRIMENTAL AT IN CHRONIC HIGH-ALTITUDE HYPOXIA. EVOLVED CHANGES IN CARDIORESPIRATORY CONTROL HAVE ARISEN IN MANY HIGH-ALTITUDE TAXA, INCLUDING INCREASES IN EFFECTIVE VENTILATION, ATTENUATION OF HYPOXIC PULMONARY VASOCONSTRICTION, AND CHANGES IN CATECHOLAMINE SENSITIVITY OF THE HEART AND SYSTEMIC VASCULATURE. PARALLEL EVOLUTION OF SOME OF THESE CHANGES IN INDEPENDENT HIGHLAND LINEAGES SUPPORTS THEIR ADAPTIVE SIGNIFICANCE. MUCH LESS IS KNOWN ABOUT THE GENOMIC BASES AND POTENTIAL INTERACTIVE EFFECTS OF ADAPTATION, ACCLIMATIZATION, DEVELOPMENTAL PLASTICITY, AND TRANS-GENERATIONAL EPIGENETIC TRANSFER ON CARDIORESPIRATORY CONTROL. FUTURE WORK TO UNDERSTAND THESE VARIOUS INFLUENCES ON BREATHING AND CIRCULATION IN HIGH-ALTITUDE NATIVES WILL HELP ELUCIDATE HOW COMPLEX PHYSIOLOGICAL SYSTEMS CAN BE PUSHED TO THEIR LIMITS TO MAINTAIN CELLULAR FUNCTION IN HYPOXIA. 2015 8 4138 34 MECHANISMS OF MICROGLIAL ACTIVATION IN MODELS OF INFLAMMATION AND HYPOXIA: IMPLICATIONS FOR CHRONIC INTERMITTENT HYPOXIA. CHRONIC INTERMITTENT HYPOXIA (CIH) IS A HALLMARK OF SLEEP APNOEA, A CONDITION ASSOCIATED WITH DIVERSE CLINICAL DISORDERS. CIH AND SLEEP APNOEA ARE CHARACTERIZED BY INCREASED REACTIVE OXYGEN SPECIES FORMATION, PERIPHERAL AND CNS INFLAMMATION, NEURONAL DEATH AND NEUROCOGNITIVE DEFICITS. FEW STUDIES HAVE EXAMINED THE ROLE OF MICROGLIA, THE RESIDENT CNS IMMUNE CELLS, IN MODELS OF CIH. THUS, LITTLE IS KNOWN CONCERNING THEIR DIRECT CONTRIBUTIONS TO NEUROPATHOLOGY OR THE CELLULAR MECHANISMS REGULATING THEIR ACTIVITIES DURING OR FOLLOWING PATHOLOGICAL CIH. IN THIS REVIEW, WE IDENTIFY GAPS IN KNOWLEDGE REGARDING CIH-INDUCED MICROGLIAL ACTIVATION, AND PROPOSE MECHANISMS BASED ON DATA FROM RELATED MODELS OF HYPOXIA AND/OR HYPOXIA-REOXYGENATION. CIH MAY DIRECTLY AFFECT MICROGLIA, OR MAY HAVE INDIRECT EFFECTS VIA THE PERIPHERY OR OTHER CNS CELLS. PERIPHERAL INFLAMMATION MAY INDIRECTLY ACTIVATE MICROGLIA VIA ENTRY OF PRO-INFLAMMATORY MOLECULES INTO THE CNS, AND/OR ACTIVATION OF VAGAL AFFERENTS THAT TRIGGER CNS INFLAMMATION. CIH-INDUCED RELEASE OF DAMAGE-ASSOCIATED MOLECULAR PATTERNS FROM INJURED CNS CELLS MAY ALSO ACTIVATE MICROGLIA VIA INTERACTIONS WITH PATTERN RECOGNITION RECEPTORS EXPRESSED ON MICROGLIA. FOR EXAMPLE, TOLL-LIKE RECEPTORS ACTIVATE MITOGEN-ACTIVATED PROTEIN KINASE/TRANSCRIPTION FACTOR PATHWAYS REQUIRED FOR MICROGLIAL INFLAMMATORY GENE EXPRESSION. ALTHOUGH EPIGENETIC EFFECTS FROM CIH HAVE NOT YET BEEN STUDIED IN MICROGLIA, POTENTIAL EPIGENETIC MECHANISMS IN MICROGLIAL REGULATION ARE DISCUSSED, INCLUDING MICRORNAS, HISTONE MODIFICATIONS AND DNA METHYLATION. EPIGENETIC EFFECTS CAN OCCUR DURING CIH, OR LONG AFTER IT HAS ENDED. A BETTER UNDERSTANDING OF CIH EFFECTS ON MICROGLIAL ACTIVITIES MAY BE IMPORTANT TO REVERSE CIH-INDUCED NEUROPATHOLOGY IN PATIENTS WITH SLEEP DISORDERED BREATHING. 2016 9 1907 23 ENRICHED ENVIRONMENT PRIORS TO TET1 HIPPOCAMPAL ADMINISTRATION FOR REGULATING PSYCHIATRIC BEHAVIORS VIA GLIAL REACTIVITY IN CHRONIC CEREBRAL HYPOPERFUSION MODELS. BACKGROUND: CHRONIC CEREBRAL HYPOPERFUSION (CCH) HAS BEEN GRADUALLY REGARDED AS A COMMON ETIOLOGIC MECHANISM FOR COGNITIVE AND PSYCHIATRIC DISTURBANCES. TEN-ELEVEN TRANSLOCATION METHYLCYTOSINE DIOXYGENASE 1 (TET1) PLAYED AN IMPORTANT ROLE IN ADULT HIPPOCAMPAL NEUROGENESIS (AHN), NEURONAL CIRCUITS FORMATION, COGNITION AND PSYCHIATRIC DISORDERS. ENRICHED ENVIRONMENT (EE) SHOWED A BENEFICIAL EFFECT ON COGNITION AND DEPRESSION VIA EFFECTIVELY REGULATING AHN AND GLIAL REACTIVITY. THIS STUDY AIMED TO ASSESS WHICH STRATEGY WAS FEASIBLE TO IMPROVE COGNITION AND PSYCHIATRIC DISTURBANCES BY COMPARING THE TET1 HIPPOCAMPAL MICROINJECTION AND EE IN CCH MODELS AND TO INVESTIGATE THE POSSIBLE MECHANISMS. METHOD: CCH RATS WERE ESTABLISHED VIA PERMANENT BILATERAL COMMON CAROTID ARTERY OCCLUSION (2-VO). RATS WERE STEREOTAXICALLY INJECTED WITH THE HUMAN CATALYTIC DOMAIN OF TET1 (HTET1) TO OVEREXPRESS THE HTET1 IN THE HIPPOCAMPUS 10 DAYS BEFORE 2-VO. 3 DAYS AFTER 2-VO, RATS WERE SUBJECTED TO STANDARD ENVIRONMENT OR EE WITH FREE ACCESS TO FOOD AND WATER. BEHAVIORAL TESTS WERE USED TO APPRAISE DEPRESSION AND COGNITION BEFORE SACRIFICE. EPIGENETIC MOLECULES, ADULT NEUROGENESIS, SYNAPTIC PROTEINS EXPRESSION, AND GLIAL ACTIVATION WERE ANALYZED USING IMMUNOFLUORESCENT STAINING, QRT-PCR AND WESTERN BLOT. RESULTS: IN THE PRESENT STUDY, WE FOUND BOTH EE AND GENETICAL TREATMENT WITH OVEREXPRESSING HTET1 WERE SUFFICIENT FOR STIMULATING AHN. HOWEVER, PROMOTING ANH COULD NOT DEAL WITH THE COGNITIVE DYSFUNCTION AND DEPRESSIVE-LIKE BEHAVIORS IN CCH RATS. NOTABLY, A HEALTHY LOCAL BRAIN ENVIRONMENT WITH ELEVATED BDNF AND ASTROCYTES WAS CONDUCIVE TO IMPROVING COGNITIVE DYSFUNCTION. MEANWHILE, ASTROCYTES WERE INVOLVED IN THE COGNITIVE REGULATING PROCESS OF NEURONS, PRESYNAPTIC FUNCTION AND MICROGLIA. IN GENERAL, WE HELD THAT DEPRESSIVE DISTURBANCES WERE DETERMINED BY BDNF LEVELS, NEURONAL AND PRESYNAPTIC FUNCTION, AS WELL AS GLIAL ACTIVATION CONTAINING ASTROCYTES AND MICROGLIA. TO FURTHER SUPPORT THIS POINT, WE INVESTIGATED SEVERE DEPRESSIVE SYMPTOMS THAT WERE STRONGLY CORRELATED WITH THE ACTIVATION OF ASTROGLIA AND MICROGLIA. IMPORTANTLY, CAUSAL MEDIATION ANALYSIS SHOWED SIGNIFICANT MEDIATION BY THE PRESENCE OF REACTIVE GLIAL CELLS IN THE RELATION BETWEEN NEURAL PLASTICITY AND DEPRESSIVE SYMPTOMS. FINALLY, WE SHOWED EE PERFORMED BETTER THAN HTET1 TREATMENT FOR COGNITIVE DEFICITS AND DEPRESSION. EE WITH LESS GLIAL REACTIVITY WAS MUCH MORE RESISTANT TO DEPRESSION, WHILE HTET1 WITH MORE GLIAL ACTIVATION WAS MORE VULNERABLE TO DEPRESSIVE DISORDERS. CONCLUSIONS: EE WAS LIKELY TO BE SUPERIOR TO TET1 HIPPOCAMPAL ADMINISTRATION FOR COGNITION AND PSYCHIATRIC BEHAVIORS IN CCH RATS. FURTHERMORE, A HEALTHY LOCAL BRAIN ENVIRONMENT WITH ELEVATED BDNF AND ASTROCYTES WAS CONDUCIVE TO IMPROVING COGNITIVE DYSFUNCTION. MORE GLIAL ACTIVATION, AND MORE VULNERABLE TO DEPRESSIVE DISORDERS. THESE RESULTS WERE IMPORTANT FOR OUR UNDERSTANDING OF DISEASE MECHANISMS AND PROVIDED VALUABLE TOOLS FOR THE OVERALL MANAGEMENT OF CCH PATIENTS. 2022 10 6108 22 THE ENRICHED ENVIRONMENT AMELIORATES CHRONIC UNPREDICTABLE MILD STRESS-INDUCED DEPRESSIVE-LIKE BEHAVIORS AND COGNITIVE IMPAIRMENT BY ACTIVATING THE SIRT1/MIR-134 SIGNALING PATHWAY IN HIPPOCAMPUS. BACKGROUND: CHRONIC UNPREDICTABLE MILD STRESS (CUMS) IS AN IMPORTANT RISK FACTOR FOR DEPRESSION AND COGNITIVE DEFICITS IN HUMANS. ENRICHED ENVIRONMENT (EE) SHOWED A BENEFICIAL EFFECT ON DEPRESSION AND COGNITION BY ENHANCING BRAIN DERIVED NEUROTROPHIC FACTOR (BDNF) EXPRESSION AND SYNAPTIC PLASTICITY. HOWEVER, IT IS STILL NOT CLEARLY UNDERSTOOD WHETHER AN EPIGENETIC MECHANISM IS INVOLVED IN THE BDNF MODULATION AND SYNAPTIC PLASTICITY THAT OCCURS AFTER EE TREATMENT FOR THE DEPRESSIVE-LIKE BEHAVIORS AND COGNITIVE DEFICITS ELICITED BY CUMS. IN THIS STUDY, WE INVESTIGATED THE POSSIBLE MECHANISM OF THE NEUROPROTECTIVE EFFECT OF EE. METHODS: ALL RATS WERE EXPOSED TO THE 5-WEEK CUMS PROCEDURE EXCEPT THE CONTROL GROUP. AFTER CUMS PROCEDURE, SOME RATS WERE STEREOTAXICALLY INJECTED WITH SIRT1 PHARMACOLOGIC INHIBITOR EX527 OR SIRT1 KNOCKING DOWN LENTIVIRUS (SH-SIRT1) IN THE HIPPOCAMPUS FOLLOWED BY EE TREATMENT FOR 3 WEEKS. OTHER RATS WERE DIRECTLY SUBJECTED TO EE TREATMENT WITHOUT STEREOTAXIC INJECTION. BEHAVIORAL TESTS WERE USED TO APPRAISE DEPRESSION AND COGNITION AFTER EE TREATMENT. THEN EPIGENETIC MOLECULES, SYNAPTIC PROTEINS, DENDRITIC SPINE DENSITY AND BRANCHES, AND SYNAPTIC MORPHOLOGY OF THE DORSAL HIPPOCAMPUS WERE DETERMINED. RESULTS: WE FOUND THAT CUMS INDUCED DEPRESSIVE-LIKE BEHAVIORS INCLUDING DECREASED SUCROSE PREFERENCE RATIO, PROLONGED IMMOBILITY AND REDUCED LOCOMOTOR AND EXPLORATORY ACTIVITY; COGNITIVE DEFICITS INCLUDING SPATIAL LEARNING AND MEMORY IMPAIRMENT; REDUCED DENDRITIC SPINE DENSITY AND NUMBER OF BRANCHES; THINNED POSTSYNAPTIC DENSITY; DOWNREGULATED SIRT1/MICRORNA-134 PATHWAY, DECREASED BDNF AND SYNAPTIC PROTEINS INCLUDING SYNAPTOPHYSIN (SYN) AND POSTSYNAPTIC DENSITY PROTEIN 95 (PSD95) EXPRESSION IN THE HIPPOCAMPUS. HOWEVER, THE CUMS-INDUCED DEPRESSIVE-LIKE BEHAVIORS, COGNITIVE DEFICITS, DENDRITIC SPINE DENSITY AND BRANCH NUMBER REDUCTION, POSTSYNAPTIC DENSITY THINNING, SIRT1/MICRORNA-134 PATHWAY DOWNREGULATION, BDNF AND SYNAPTIC PROTEINS REDUCTION, INCLUDING SYNAPTOPHYSIN (SYN) AND POSTSYNAPTIC DENSITY PROTEIN 95 (PSD95), WERE REVERSED BY EE TREATMENT. HOWEVER, DEPRESSIVE-LIKE BEHAVIORS AND COGNITIVE DEFICITS WERE OBSERVED AGAIN IN RATS SUBJECTED TO STEREOTAXIC INJECTION WITH EX527 OR SH-SIRT1. FURTHERMORE, THIS STUDY ALSO FOUND THAT SIRT1/MICRORNA-134 REGULATES THE DOWNSTREAM MOLECULES BDNF, AND THE SYNAPTIC PROTEINS SYN AND PSD95 IN PRIMARY CULTURED HIPPOCAMPAL NEURONS. CONCLUSIONS: THIS STUDY PROVIDES EVIDENCE FOR THE NEUROPROTECTIVE ROLE OF EE ON DEPRESSION AND COGNITIVE DEFICITS BY ACTIVATING THE SIRT1/MICRORNA-134 PATHWAY, WHICH ACCOUNTS FOR THE REGULATION OF SYNAPTIC PROTEINS, INCLUDING BDNF, PSD95 AND SYN, DENDRITIC REMODELING AND ULTRASTRUCTURE CHANGES OF SYNAPSES IN THE HIPPOCAMPUS. 2019 11 1761 18 EARLY STRESS EVOKES AGE-DEPENDENT BIPHASIC CHANGES IN HIPPOCAMPAL NEUROGENESIS, BDNF EXPRESSION, AND COGNITION. BACKGROUND: ADULT-ONSET STRESSORS EXERT OPPOSING EFFECTS ON HIPPOCAMPAL NEUROGENESIS AND COGNITION, WITH ENHANCEMENT OBSERVED FOLLOWING MILD STRESS AND DYSFUNCTION FOLLOWING SEVERE CHRONIC STRESS. WHILE EARLY LIFE STRESS EVOKES PERSISTENT CHANGES IN ANXIETY, IT IS UNKNOWN WHETHER EARLY STRESS DIFFERENTIALLY REGULATES HIPPOCAMPAL NEUROGENESIS, TROPHIC FACTOR EXPRESSION, AND COGNITION ACROSS THE LIFE SPAN. METHODS: HIPPOCAMPAL-DEPENDENT COGNITIVE BEHAVIOR, NEUROGENESIS, AND EPIGENETIC REGULATION OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) EXPRESSION WAS EXAMINED AT DISTINCT TIME POINTS ACROSS THE LIFE SPAN IN RATS SUBJECTED TO THE EARLY STRESS OF MATERNAL SEPARATION (ES) AND CONTROL GROUPS. WE ALSO EXAMINED THE INFLUENCE OF CHRONIC ANTIDEPRESSANT TREATMENT ON THE NEUROGENIC, NEUROTROPHIC, AND COGNITIVE CHANGES IN MIDDLE-AGED ES ANIMALS. RESULTS: ANIMALS SUBJECTED TO EARLY STRESS OF MATERNAL SEPARATION EXAMINED DURING POSTNATAL LIFE AND YOUNG ADULTHOOD EXHIBITED ENHANCED HIPPOCAMPAL NEUROGENESIS, DECREASED REPRESSIVE HISTONE METHYLATION AT THE BDNF IV PROMOTER ALONG WITH ENHANCED BDNF LEVELS, AND IMPROVED PERFORMANCE ON THE STRESS-ASSOCIATED MORRIS WATER MAZE. STRIKINGLY, OPPOSING CHANGES IN HIPPOCAMPAL NEUROGENESIS AND EPIGENETIC REGULATION OF BDNF IV EXPRESSION, CONCOMITANT WITH IMPAIRMENTS ON HIPPOCAMPAL-DEPENDENT COGNITIVE TASKS, WERE OBSERVED IN MIDDLE-AGED ES ANIMALS. CHRONIC ANTIDEPRESSANT TREATMENT WITH AMITRIPTYLINE ATTENUATED THE MALADAPTIVE NEUROGENIC, EPIGENETIC, TRANSCRIPTIONAL, AND COGNITIVE EFFECTS IN MIDDLE-AGED ES ANIMALS. CONCLUSIONS: OUR STUDY PROVIDES NOVEL INSIGHTS INTO THE SHORT- AND LONG-TERM CONSEQUENCES OF ES, DEMONSTRATING BOTH BIPHASIC AND UNIQUE, AGE-DEPENDENT CHANGES AT THE MOLECULAR, EPIGENETIC, NEUROGENIC, AND BEHAVIORAL LEVELS. THESE RESULTS INDICATE THAT EARLY STRESS MAY TRANSIENTLY ENDOW ANIMALS WITH A POTENTIAL ADAPTIVE ADVANTAGE IN STRESSFUL ENVIRONMENTS BUT ACROSS A LIFE SPAN IS ASSOCIATED WITH LONG-TERM DELETERIOUS EFFECTS. 2013 12 3977 19 LONG-TERM EFFECT OF POST-TRAUMATIC STRESS IN ADOLESCENCE ON DENDRITE DEVELOPMENT AND H3K9ME2/BDNF EXPRESSION IN MALE RAT HIPPOCAMPUS AND PREFRONTAL CORTEX. EXPOSURE TO A HARSH ENVIRONMENT IN EARLY LIFE INCREASES IN THE RISK OF POST-TRAUMATIC STRESS DISORDER (PTSD) OF AN INDIVIDUAL. BRAIN DERIVED NEUROTROPHIC FACTOR (BDNF) PLAYS AN IMPORTANT ROLE IN NEURODEVELOPMENT IN DEVELOPMENTAL STAGES. BOTH CHRONIC AND TRAUMATIC STRESSES INDUCE A DECREASE IN THE LEVEL OF BDNF AND REDUCE NEURAL PLASTICITY, WHICH IS LINKED TO THE PATHOGENESIS OF PTSD. ALSO, STUDIES HAVE SHOWN THAT STRESS ALTERS THE EPIGENETIC MARKER H3K9ME2, WHICH CAN BIND TO THE PROMOTER REGION OF THE BDNF GENE AND REDUCE BDNF PROTEIN LEVEL. HOWEVER, THE LONG-TERM EFFECTS OF TRAUMATIC STRESS DURING ADOLESCENCE ON H3K9ME2, BDNF EXPRESSION AND DENDRITE DEVELOPMENT ARE NOT WELL-KNOWN. THE PRESENT STUDY ESTABLISHED A MODEL OF PTSD IN ADOLESCENT RATS USING AN INESCAPABLE FOOT SHOCK (IFS) PROCEDURE. ANXIETY-LIKE BEHAVIORS, SOCIAL INTERACTION BEHAVIOR AND MEMORY FUNCTION WERE ASSESSED BY THE OPEN FIELD TEST, ELEVATED PLUS MAZE TEST, THREE-CHAMBER SOCIABILITY TEST AND MORRIS WATER MAZE TEST. IN ADDITION, NEURONAL DEVELOPMENT AND H3K9ME2/BDNF EXPRESSION IN HIPPOCAMPUS (HIP) AND PREFRONTAL CORTEX (PFC) WERE EVALUATED BY GOLGI STAINING, WESTERN BLOTTING, QRT-PCR ANALYSIS AND CHIP-QPCR ANALYSIS. ADDITIONALLY, THE UNC0642, A SMALL MOLECULE INHIBITOR OF HISTONE METHYLTRANSFERASE (EHMT2) WAS USED FOR INTERVENTION. THE RESULTS SHOWED THAT THE IFS PROCEDURE INDUCED THE PTSD-LIKE BEHAVIORS IN RATS, RESULTED IN FEWER DENDRITE BRANCHES AND SHORTER DENDRITE LENGTH IN CA1 OF HIP AND PFC, INCREASED H3K9ME2 LEVEL AND DECREASED BDNF EXPRESSION IN HIP AND PFC. ALSO, ALTHOUGH ALL THE CHANGES CAN PERSIST TO ADULTHOOD, UNC0642 ADMINISTRATION RELIEVED MOST OF ALTERATIONS. OUR STUDY SUGGESTS THAT TRAUMATIC STRESS IN ADOLESCENCE LEADS TO IMMEDIATE AND LONG-TERM MENTAL DISORDERS, NEURONAL MORPHOLOGICAL CHANGES, LOWER BDNF LEVEL AND INCREASED H3K9ME2 LEVEL IN THE HIP AND PFC, INDICATING THAT H3K9ME2/BDNF DYSFUNCTION PLAYS A KEY ROLE IN PATHOGENESIS OF PTSD. 2020 13 219 21 ACUTE IMMOBILIZATION STRESS FOLLOWING CONTEXTUAL FEAR CONDITIONING REDUCES FEAR MEMORY: TIMING IS ESSENTIAL. BACKGROUND: HISTONE ACETYLATION IS REGULATED IN RESPONSE TO STRESS AND PLAYS AN IMPORTANT ROLE IN LEARNING AND MEMORY. CHRONIC STRESS IS KNOWN TO DETERIORATE COGNITION, WHEREAS ACUTE STRESS FACILITATES MEMORY FORMATION. HOWEVER, WHETHER ACUTE STRESS FACILITATES MEMORY FORMATION WHEN IT IS APPLIED AFTER FEAR STIMULATION IS NOT YET KNOWN. THEREFORE, THIS STUDY AIMED TO INVESTIGATE THE EFFECT OF ACUTE STRESS APPLIED AFTER FEAR TRAINING ON MEMORY FORMATION, MRNA EXPRESSION OF BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF), EPIGENETIC REGULATION OF BDNF EXPRESSION, AND CORTICOSTERONE LEVEL IN MICE IN VIVO. METHODS: MICE WERE SUBJECTED TO ACUTE IMMOBILIZATION STRESS FOR 30 MIN AT 60 OR 90 MIN AFTER CONTEXTUAL FEAR CONDITIONING TRAINING, AND ACETYLATION OF HISTONE 3 AT LYSINE 14 (H3K14) AND LEVEL OF CORTICOSTERONE WERE MEASURED USING WESTERN BLOT ANALYSIS AND ENZYME-LINKED IMMUNOSORBENT ASSAY (ELISA), RESPECTIVELY. A FREEZING BEHAVIOR TEST WAS PERFORMED 24 H AFTER TRAINING, AND MRNA EXPRESSION OF BDNF WAS MEASURED USING REAL-TIME POLYMERASE CHAIN REACTIONS. DIFFERENT GROUPS OF MICE WERE USED FOR EACH TEST. RESULTS: FREEZING BEHAVIOR SIGNIFICANTLY DECREASED WITH THE DOWN-REGULATION OF BDNF MRNA EXPRESSION CAUSED BY ACUTE IMMOBILIZATION STRESS AT 60 MIN AFTER FEAR CONDITIONING TRAINING OWING TO THE REDUCTION OF H3K14 ACETYLATION. HOWEVER, BDNF MRNA EXPRESSION AND H3K14 ACETYLATION WERE NOT REDUCED IN ANIMALS SUBJECTED TO IMMOBILIZATION STRESS AT 90 MIN AFTER THE TRAINING. FURTHER, THE CORTICOSTERONE LEVEL WAS SIGNIFICANTLY HIGH IN MICE SUBJECTED TO IMMOBILIZATION STRESS AT 60 MIN AFTER THE TRAINING. CONCLUSION: ACUTE IMMOBILIZATION STRESS FOR 30 MIN AT 60 MIN AFTER FEAR CONDITIONING TRAINING IMPAIRED MEMORY FORMATION AND REDUCED BDNF MRNA EXPRESSION AND H3K14 ACETYLATION IN THE HIPPOCAMPUS OF MICE OWING TO THE HIGH LEVEL OF CORTICOSTERONE. 2016 14 4092 20 MATERNAL REPETITIVE HYPOXIA PRIOR TO MATING CONFERS EPIGENETIC RESILIENCE TO MEMORY IMPAIRMENT IN MALE PROGENY. WE SHOWED PREVIOUSLY IN A MOUSE MODEL OF VASCULAR COGNITIVE IMPAIRMENT AND DEMENTIA INVOLVING CHRONIC CEREBRAL HYPOPERFUSION (CCH) THAT REPETITIVE HYPOXIC CONDITIONING (RHC) OF BOTH PARENTS RESULTS IN THE EPIGENETIC, INTERGENERATIONAL TRANSMISSION OF RESILIENCE TO RECOGNITION MEMORY LOSS IN ADULT PROGENY, AS ASSESSED BY THE NOVEL OBJECT RECOGNITION TEST. THE PRESENT STUDY WAS UNDERTAKEN IN THE SAME MODEL TO DETERMINE WHETHER RHC TREATMENT OF ONE OR BOTH PARENTS IS REQUIRED TO CONFER DEMENTIA RESILIENCE INTERGENERATIONALLY. WE FOUND INHERITED RESILIENCE TO 3 MONTHS OF CCH IN MALES IS MATERNALLY MEDIATED (P = .006). STATISTICALLY, WE OBSERVED A STRONG TREND FOR THE PATERNAL GERMLINE TO CONTRIBUTE AS WELL (P = .052). WE ALSO FOUND THAT, IN CONTRAST TO WHAT IS WIDELY OBSERVED IN MALES, FEMALES DISPLAY INTACT RECOGNITION MEMORY (P = .001) AFTER 3 MONTHS OF CCH, REVEALING A HERETOFORE UNIDENTIFIED SEXUAL DIMORPHISM WITH RESPECT TO COGNITIVE IMPACT DURING DISEASE PROGRESSION. OVERALL, RESULTS OF OUR STUDY STRONGLY IMPLICATE EPIGENETIC CHANGES IN MATERNAL GERM CELLS, INDUCED BY OUR REPETITIVE SYSTEMIC HYPOXIC STIMULUS, CONTRIBUTING TO A MODIFIED DIFFERENTIATION PROGRAM CAPABLE OF ESTABLISHING A DEMENTIA-RESILIENT PHENOTYPE IN ADULT MALE FIRST-GENERATION PROGENY. (PSYCINFO DATABASE RECORD (C) 2023 APA, ALL RIGHTS RESERVED). 2023 15 4109 29 MECHANISMS AND DRUG THERAPY OF PULMONARY HYPERTENSION AT HIGH ALTITUDE. PULMONARY VASOCONSTRICTION REPRESENTS A PHYSIOLOGICAL ADAPTIVE MECHANISM TO HIGH ALTITUDE. IF EXAGGERATED, HOWEVER, IT IS ASSOCIATED WITH IMPORTANT MORBIDITY AND MORTALITY. RECENT MECHANISTIC STUDIES USING SHORT-TERM ACUTE HIGH ALTITUDE EXPOSURE HAVE PROVIDED INSIGHT INTO THE IMPORTANCE OF DEFECTIVE VASCULAR ENDOTHELIAL AND RESPIRATORY EPITHELIAL NITRIC OXIDE (NO) SYNTHESIS, INCREASED ENDOTHELIN-1 BIOAVAILABILITY, AND OVERACTIVATION OF THE SYMPATHETIC NERVOUS SYSTEM IN CAUSING EXAGGERATED HYPOXIC PULMONARY HYPERTENSION IN HUMANS. BASED ON THESE STUDIES, DRUGS THAT INCREASE NO BIOAVAILABILITY, ATTENUATE ENDOTHELIN-1 INDUCED PULMONARY VASOCONSTRICTION, OR PREVENT EXAGGERATED SYMPATHETIC ACTIVATION HAVE BEEN SHOWN TO BE USEFUL FOR THE TREATMENT/PREVENTION OF EXAGGERATED PULMONARY HYPERTENSION DURING ACUTE SHORT-TERM HIGH ALTITUDE EXPOSURE. THE MECHANISMS UNDERPINNING CHRONIC PULMONARY HYPERTENSION IN HIGH ALTITUDE DWELLERS ARE LESS WELL UNDERSTOOD, BUT RECENT EVIDENCE SUGGESTS THAT THEY DIFFER IN SOME ASPECTS FROM THOSE INVOLVED IN SHORT-TERM ADAPTATION TO HIGH ALTITUDE. THESE DIFFERENCES HAVE CONSEQUENCES FOR THE CHOICE OF THE TREATMENT FOR CHRONIC PULMONARY HYPERTENSION AT HIGH ALTITUDE. FINALLY, RECENT DATA INDICATE THAT FETAL PROGRAMMING OF PULMONARY VASCULAR DYSFUNCTION IN OFFSPRING OF PREECLAMPSIA AND CHILDREN GENERATED BY ASSISTED REPRODUCTIVE TECHNOLOGIES REPRESENTS A NOVEL AND FREQUENT CAUSE OF PULMONARY HYPERTENSION AT HIGH ALTITUDE. IN ANIMAL MODELS OF FETAL PROGRAMMING OF HYPOXIC PULMONARY HYPERTENSION, EPIGENETIC MECHANISMS PLAY A ROLE, AND TARGETING OF THESE MECHANISMS WITH DRUGS LOWERS PULMONARY ARTERY PRESSURE. IF EPIGENETIC MECHANISMS ALSO ARE OPERATIONAL IN THE FETAL PROGRAMMING OF PULMONARY VASCULAR DYSFUNCTION IN HUMANS, SUCH DRUGS MAY BECOME NOVEL TOOLS FOR THE TREATMENT OF HYPOXIC PULMONARY HYPERTENSION. 2013 16 1839 17 EFFECTS OF PRENATAL NICOTINE EXPOSURE ON HEPATIC GLUCOSE AND LIPID METABOLISM IN OFFSPRING RATS AND ITS HEREDITABILITY. PRENATAL NICOTINE EXPOSURE (PNE) COULD INDUCE AN INCREASED SUSCEPTIBILITY TO MULTIPLE CHRONIC DISEASES IN ADULT OFFSPRING, THAT MAINLY CAUSED BY INTRAUTERINE MATERNAL GLUCOCORTICOID (GC) OVER-EXPOSURE. WE INVESTIGATED THE CHANGES AND INHERITABILITY OF HEPATIC GLUCOSE AND LIPID METABOLISM CAUSED BY PNE, TO DECIPHER THE POSSIBLE INTRAUTERINE PROGRAMMING MECHANISM. PREGNANT WISTAR RATS WERE ADMINISTERED SUBCUTANEOUSLY WITH 2 MG/KG.D NICOTINE FROM GESTATIONAL DAY (GD) 9 APPROXIMATELY 20, AND SECOND-GENERATION (F2) WERE SET ACCORDING TO THE MATING BETWEEN CONTROL FEMALES AND PNE MALES. THE RESULTS SHOWED THAT SERUM PHENOTYPES AND HEPATIC ENZYMES OF GLUCOSE AND LIPID METABOLISM WERE LOWER IN F1 FETAL RATS OF PNE BUT HIGHER IN THE F1 ADULT RATS. MEANWHILE, THE ACTIVATED STATES OF HEPATIC GLUCOCORTICOID-ACTIVATION SYSTEM, INCLUDING TYPE 1 AND TYPE 2 11BETA-HYDROXYSTEROID DEHYDROGENASES (HSD11B1/2), NUCLEAR RECEPTOR SUBFAMILY 3, GROUP C, MEMBER 1 (NR3C1) AND CCAAT ENHANCER BINDING PROTEIN ALPHA (CEBPA), WERE POSITIVELY CORRELATED WITH SERUM CORTICOSTERONE LEVELS BUT NEGATIVELY CORRELATED WITH THE HISTONE ACETYLATION (H3K27AC) AND EXPRESSION LEVELS OF INSULIN-LIKE GROWTH FACTOR 1 (IGF1) BEFORE AND AFTER BIRTH. FURTHERMORE, SERUM PHENOTYPES AND HEPATIC ENZYMES OF GLUCOSE AND LIPID METABOLISM WERE LOWER IN BOTH F2 FETAL AND ADULT RATS OF PNE, WHICH WERE CONSISTENT WITH THE HEPATIC CHANGES OF GC-IGF1 AXIS AND THE GLUCOCORTICOID-ACTIVATION SYSTEM. IN CONCLUSION, PNE COULD LEAD TO INHERITABLE CHANGES OF HEPATIC GLUCOSE AND LIPID METABOLISM, WHICH ARE RELATED TO THE INTRAUTERINE PROGRAMMING OF GC-IGF1 AXIS INDUCED BY THE GLUCOCORTICOID-ACTIVATION SYSTEM. 2020 17 5207 21 PRENATAL STRESS INDUCES SPATIAL MEMORY DEFICITS AND EPIGENETIC CHANGES IN THE HIPPOCAMPUS INDICATIVE OF HETEROCHROMATIN FORMATION AND REDUCED GENE EXPRESSION. STRESS DURING PREGNANCY HAS A WIDE VARIETY OF NEGATIVE EFFECTS IN BOTH HUMAN [1] AND ANIMAL OFFSPRING [2]. THESE EFFECTS ARE ESPECIALLY APPARENT IN VARIOUS FORMS OF LEARNING AND MEMORY SUCH AS OBJECT RECOGNITION [3] AND SPATIAL MEMORY [4]. THE COGNITIVE EFFECTS OF PRENATAL STRESS (PNS) MAY BE MEDIATED THROUGH EPIGENETIC CHANGES SUCH AS HISTONE ACETYLATION AND DNA METHYLATION [5]. AS SUCH, THE PRESENT STUDY INVESTIGATED THE EFFECTS OF CHRONIC UNPREDICTABLE PNS ON MEMORY AND EPIGENETIC MEASURES IN ADULT OFFSPRING. MICE THAT UNDERWENT PNS EXHIBITED IMPAIRED SPATIAL MEMORY IN THE MORRIS WATER MAZE, AS WELL AS SEX-SPECIFIC CHANGES IN LEVELS OF DNA METHYLTRANSFERASE (DNMT) 1 PROTEIN, AND ACETYLATED HISTONE H3 (ACH3) IN THE HIPPOCAMPUS, AND SERUM CORTICOSTERONE. MALE MICE EXPOSED TO PNS EXHIBITED DECREASED HIPPOCAMPAL ACH3, WHEREAS FEMALE PNS MICE DISPLAYED A FURTHER REDUCTION IN ACH3, AS WELL AS HEIGHTENED HIPPOCAMPAL DNMT1 PROTEIN LEVELS AND CORTICOSTERONE LEVELS. THESE DATA SUGGEST THAT PNS MAY EPIGENETICALLY REDUCE TRANSCRIPTION IN THE HIPPOCAMPUS, PARTICULARLY IN FEMALES IN WHOM THIS EFFECT MAY BE RELATED TO INCREASED BASELINE STRESS HORMONE LEVELS, AND WHICH MAY UNDERLIE THE SEXUAL DIMORPHISM IN RATES OF MENTAL ILLNESS IN HUMANS. 2015 18 4069 16 MATERNAL CHRONIC FOLATE SUPPLEMENTATION AMELIORATES BEHAVIOR DISORDERS INDUCED BY PRENATAL HIGH-FAT DIET THROUGH METHYLATION ALTERATION OF BDNF AND GRIN2B IN OFFSPRING HIPPOCAMPUS. SCOPE: MATERNAL CONSUMPTION OF A HIGH-FAT DIET (HFD) DURING PREGNANCY INCREASES THE RISK OF BEHAVIORAL PROBLEMS. FOLATE PLAYS AN IMPORTANT ROLE IN NEUROPLASTICITY AND THE PRESERVATION OF NEURONAL INTEGRITY. THIS STUDY AIMS AT DETERMINING THE INFLUENCE OF DIETS SUPPLEMENTED WITH FOLATE ON OFFSPRING BEHAVIOR, AND THE MECHANISMS INVOLVED. METHODS AND RESULTS: FEMALE MICE WERE FED A CONTROL DIET, AN HFD, CONTROL DIET SUPPLEMENTED WITH FOLATE, OR AN HFD SUPPLEMENTED WITH FOLATE FOR 5 WEEKS BEFORE MATING. OPEN FIELD TASK AND ELEVATED PLUS MAZE ARE USED TO EVALUATE THE OFFSPRING BEHAVIORS. RESULTS SHOWED THAT OFFSPRING COGNITIVE PERFORMANCE AND ANXIETY-RELATED BEHAVIORS, INCLUDING THOSE RELATED TO OPEN FIELD EXPLORATION AND ELEVATED PLUS MAZE, WERE SIGNIFICANTLY IMPROVED WHEN DAMS WERE TREATED WITH FOLATE IN PREGNANCY. MOREOVER, THE MATERNAL FOLATE SUPPLEMENT DECREASED BDNF AND GRIN2B METHYLATION AND UPREGULATED THEIR EXPRESSIONS IN THE BRAIN OF OFFSPRING, WHICH WERE ASSOCIATED WITH DECREASING THE EXPRESSION OF DNA METHYLTRANSFERASES COMPARED WITH THOSE DAMS WERE TREATED ONLY HFD IN PREGNANCY. CONCLUSION: MATERNAL FOLATE SUPPLEMENTATION AMELIORATES BEHAVIOR DISORDERS INDUCED BY PRENATAL HIGH-FAT DIET. THE BENEFICIAL EFFECTS WERE ASSOCIATED WITH METHYLATION AND EXPRESSION ALTERATION OF BDNF AND GRIN2B GENES. 2017 19 443 29 AORTA MACROPHAGE INFLAMMATORY AND EPIGENETIC CHANGES IN A MURINE MODEL OF OBSTRUCTIVE SLEEP APNEA: POTENTIAL ROLE OF CD36. OBSTRUCTIVE SLEEP APNEA (OSA) AFFECTS 8-10% OF THE POPULATION, IS CHARACTERIZED BY CHRONIC INTERMITTENT HYPOXIA (CIH), AND CAUSALLY ASSOCIATES WITH CARDIOVASCULAR MORBIDITIES. IN CIH-EXPOSED MICE, CLOSELY MIMICKING THE CHRONICITY OF HUMAN OSA, INCREASED ACCUMULATION AND PROLIFERATION OF PRO-INFLAMMATORY METABOLIC M1-LIKE MACROPHAGES HIGHLY EXPRESSING CD36, EMERGED IN AORTA. TRANSCRIPTOMIC AND MEDIP-SEQ APPROACHES IDENTIFIED ACTIVATION OF PRO-ATHEROGENIC PATHWAYS INVOLVING A COMPLEX INTERPLAY OF HISTONE MODIFICATIONS IN FUNCTIONALLY-RELEVANT BIOLOGICAL PATHWAYS, SUCH AS INFLAMMATION AND OXIDATIVE STRESS IN AORTA MACROPHAGES. DISCONTINUATION OF CIH DID NOT ELICIT SIGNIFICANT IMPROVEMENTS IN AORTA WALL MACROPHAGE PHENOTYPE. HOWEVER, CIH-INDUCED AORTA CHANGES WERE ABSENT IN CD36 KNOCKOUT MICE, OUR RESULTS PROVIDE MECHANISTIC INSIGHTS SHOWING THAT CIH EXPOSURES DURING SLEEP IN ABSENCE OF CONCURRENT PRO-ATHEROGENIC SETTINGS (I.E., GENETIC PROPENSITY OR DIETARY MANIPULATION) LEAD TO THE RECRUITMENT OF CD36(+)(HIGH) MACROPHAGES TO THE AORTIC WALL AND TRIGGER ATHEROGENESIS. FURTHERMORE, LONG-TERM CIH-INDUCED CHANGES MAY NOT BE REVERSIBLE WITH USUAL OSA TREATMENT. 2017 20 2827 17 FLUOXETINE INCREASES HIPPOCAMPAL NEUROGENESIS AND INDUCES EPIGENETIC FACTORS BUT DOES NOT IMPROVE FUNCTIONAL RECOVERY AFTER TRAUMATIC BRAIN INJURY. THE SELECTIVE SEROTONIN REUPTAKE INHIBITOR FLUOXETINE INDUCES HIPPOCAMPAL NEUROGENESIS, STIMULATES MATURATION AND SYNAPTIC PLASTICITY OF ADULT HIPPOCAMPAL NEURONS, AND REDUCES MOTOR/SENSORY AND MEMORY IMPAIRMENTS IN SEVERAL CNS DISORDERS. IN THE SETTING OF TRAUMATIC BRAIN INJURY (TBI), ITS EFFECTS ON NEUROPLASTICITY AND FUNCTION HAVE YET TO BE THOROUGHLY INVESTIGATED. HERE WE EXAMINED THE EFFICACY OF FLUOXETINE AFTER A MODERATE TO SEVERE TBI, PRODUCED BY A CONTROLLED CORTICAL IMPACT. THREE DAYS AFTER TBI OR SHAM SURGERY, MICE WERE TREATED WITH FLUOXETINE (10 MG/KG/D) OR VEHICLE FOR 4 WEEKS. TO EVALUATE THE EFFECTS OF FLUOXETINE ON NEUROPLASTICITY, HIPPOCAMPAL NEUROGENESIS AND EPIGENETIC MODIFICATION WERE STUDIED. STEREOLOGIC ANALYSIS OF THE DENTATE GYRUS REVEALED A SIGNIFICANT INCREASE IN DOUBLECORTIN-POSITIVE CELLS IN BRAIN-INJURED ANIMALS TREATED WITH FLUOXETINE RELATIVE TO CONTROLS, A FINDING CONSISTENT WITH ENHANCED HIPPOCAMPAL NEUROGENESIS. EPIGENETIC MODIFICATIONS, INCLUDING AN INCREASE IN HISTONE 3 ACETYLATION AND INDUCTION OF METHYL-CPG-BINDING PROTEIN, A TRANSCRIPTION FACTOR INVOLVED IN DNA METHYLATION, WERE LIKEWISE SEEN BY IMMUNOHISTOCHEMISTRY AND QUANTITATIVE WESTERN IMMUNOBLOTS, RESPECTIVELY, IN BRAIN-INJURED ANIMALS TREATED WITH FLUOXETINE. TO DETERMINE IF FLUOXETINE IMPROVES NEUROLOGICAL OUTCOMES AFTER TBI, GAIT FUNCTION AND SPATIAL LEARNING AND MEMORY WERE ASSESSED BY THE CATWALK-ASSISTED GAIT TEST AND BARNES MAZE TEST, RESPECTIVELY. NO DIFFERENCES IN THESE PARAMETERS WERE SEEN BETWEEN FLUOXETINE- AND VEHICLE-TREATED ANIMALS. THUS WHILE FLUOXETINE ENHANCED NEUROPLASTICITY IN THE HIPPOCAMPUS AFTER TBI, ITS CHRONIC ADMINISTRATION DID NOT RESTORE LOCOMOTOR FUNCTION OR AMELIORATE MEMORY DEFICITS. 2011