1 5873 150 SWEET SUCCESS, BITTER DEFEAT: A TASTE PHENOTYPE PREDICTS SOCIAL STATUS IN SELECTIVELY BRED RATS. FOR SOCIAL OMNIVORES SUCH AS RATS AND HUMANS, TASTE IS FAR MORE THAN A CHEMICAL SENSE ACTIVATED BY FOOD. BY VIRTUE OF EVOLUTIONARY AND EPIGENETIC ELABORATION, TASTE IS ASSOCIATED WITH NEGATIVE AFFECT, STRESS VULNERABILITY, RESPONSES TO PSYCHOACTIVE SUBSTANCES, PAIN, AND SOCIAL JUDGMENT. A CRUCIAL GAP IN THIS LITERATURE, WHICH SPANS BEHAVIOR GENETICS, AFFECTIVE AND SOCIAL NEUROSCIENCE, AND EMBODIED COGNITION, CONCERNS LINKS BETWEEN TASTE AND SOCIAL BEHAVIOR IN RATS. HERE WE SHOW THAT RATS SELECTIVELY BRED FOR LOW SACCHARIN INTAKE ARE SUBORDINATE TO HIGH-SACCHARIN-CONSUMING RATS WHEN THEY COMPETE IN WEIGHT-MATCHED DYADS FOR FOOD, A TASK USED TO MODEL DEPRESSION. STATISTICAL AND EXPERIMENTAL CONTROLS SUGGEST THAT DIFFERENTIAL RESOURCE UTILIZATION WITHIN DYADS IS NOT AN ARTIFACT OF INDIVIDUAL-LEVEL PROCESSES SUCH AS APPARATUS HABITUATION OR INGESTIVE MOTIVATION. TAIL SKIN TEMPERATURE MEASUREMENTS SHOWED THAT LOS RATS DISPLAY LARGER HYPERTHERMIC RESPONSES TO SOCIAL INTERACTION AFTER STATUS IS ESTABLISHED, EVIDENCE LINKING TASTE, SOCIAL STRESS, AUTONOMIC REACTIVITY, AND DEPRESSION-LIKE SYMPTOMS. BASED ON REGRESSION USING EARLY- AND LATE-COMPETITION PREDICTORS TO PREDICT DYADIC DISPARITY IN FINAL COMPETITION SCORES, WE TENTATIVELY SUGGEST THAT HIS RATS EMERGE AS DOMINANT BOTH BECAUSE OF AN "EARLY SURGE" ON THEIR PART AND BECAUSE LOS ACQUIESCE LATER. THESE FINDINGS SHOULD INVIGORATE THE COMPARATIVE STUDY OF INDIVIDUAL DIFFERENCES IN SOCIAL STATUS AND ITS RELATIONSHIP TO MENTAL AND PHYSICAL HEALTH. 2012 2 3714 39 INHERITANCE OF SOCIAL DOMINANCE IS ASSOCIATED WITH GLOBAL SPERM DNA METHYLATION IN INBRED MALE MICE. DOMINANCE RELATIONSHIPS BETWEEN MALES AND THEIR ASSOCIATED TRAITS ARE USUALLY HERITABLE AND HAVE IMPLICATIONS FOR SEXUAL SELECTION IN ANIMALS. IN PARTICULAR, SOCIAL DOMINANCE AND ITS RELATED MALE PHEROMONES ARE HERITABLE IN INBRED MICE; THUS, WE WONDERED WHETHER EPIGENETIC CHANGES DUE TO ALTERED LEVELS OF DNA METHYLATION DETERMINE INHERITANCE. HERE, WE USED C57BL/6 MALE MICE TO ESTABLISH A SOCIAL DOMINANCE-SUBORDINATION RELATIONSHIP THROUGH CHRONIC DYADIC ENCOUNTERS, AND THIS RELATIONSHIP AND PHEROMONE COVARIATION OCCURRED IN THEIR OFFSPRING, INDICATIVE OF HERITABILITY. THROUGH TRANSCRIPTOME SEQUENCING AND WHOLE-GENOME DNA METHYLATION PROFILING OF THE SPERM OF BOTH GENERATIONS, WE FOUND THAT DIFFERENTIAL METHYLATION OF MANY GENES WAS INDUCED BY SOCIAL DOMINANCE-SUBORDINATION IN SIRES AND COULD BE PASSED ON TO THE OFFSPRING. THESE METHYLATED GENES WERE MAINLY RELATED TO GROWTH AND DEVELOPMENT PROCESSES, NEURODEVELOPMENT, AND CELLULAR TRANSPORTATION. THE EXPRESSION OF THE GENES WITH SIMILAR FUNCTIONS IN WHOLE-GENOME METHYLATION/BISULFITE SEQUENCING WAS ALSO DIFFERENTIATED BY SOCIAL DOMINANCE-SUBORDINATION, AS REVEALED BY RNA-SEQ. IN PARTICULAR, THE GENE DENND1A, WHICH REGULATES NEURAL SIGNALING, WAS DIFFERENTIALLY METHYLATED AND EXPRESSED IN THE SPERM AND MEDIAL PREFRONTAL CORTEX IN PAIRED MALES BEFORE AND AFTER DOMINANCE-SUBORDINATION ESTABLISHMENT, SUGGESTING THE POTENTIAL EPIGENETIC CONTROL AND INHERITANCE OF SOCIAL DOMINANCE-RELATED AGGRESSION. WE SUGGEST THAT SOCIAL DOMINANCE MIGHT BE PASSED ON TO MALE OFFSPRING THROUGH SPERM DNA METHYLATION AND THAT THE DIFFERENCES COULD POTENTIALLY AFFECT MALE COMPETITION IN OFFSPRING BY AFFECTING THE DEVELOPMENT OF THE NERVOUS SYSTEM. 2023 3 73 33 A MULTI-GENERATIONAL STUDY ON LOW-DOSE BPA EXPOSURE IN WISTAR RATS: EFFECTS ON MATERNAL BEHAVIOR, FLAVOR INTAKE AND DEVELOPMENT. BISPHENOL A (BPA) IS A COMMON ENDOCRINE DISRUPTOR FOUND AS AN ENVIRONMENTAL AND FOOD CONTAMINANT. IT EXERTS BOTH DEVELOPMENTAL AND BEHAVIORAL EFFECTS, MAINLY WHEN EXPOSURE OCCURS IN EARLY LIFE. THE AIM OF THIS STUDY WAS TO DETERMINE THE MULTI-GENERATIONAL EFFECTS OF CHRONIC, HUMAN-RELEVANT LOW-DOSE EXPOSURE TO BPA ON DEVELOPMENT, MATERNAL BEHAVIOR AND FLAVOR PREFERENCE IN WISTAR RATS. BPA WAS ORALLY ADMINISTERED AT A DAILY DOSE OF 5 MUG/KG BODY WEIGHT TO F0 PREGNANT DAMS FROM THE FIRST DAY OF GESTATION (GD 1) UNTIL THE LAST DAY OF LACTATION (LD 21), AND THEN TO F1 OFFSPRING FROM WEANING (PND 21) TO ADULTHOOD (PND 100). F2 OFFSPRING WERE NOT EXPOSED. DEVELOPMENT AND CLINICAL SIGNS OF TOXICITY WERE ASSESSED DAILY. MATERNAL BEHAVIOR WAS EVALUATED BY OBSERVING NURSING AND PUP-CARING ACTIONS, AS WELL AS "NON-MATERNAL" BEHAVIORS IN F0 AND F1 DAMS FROM PARTURITION UNTIL LD 8. THE FLAVOR PREFERENCES OF F1 AND F2 OFFSPRING WERE EVALUATED BASED ON THE INTAKE OF SWEET, SALT AND FAT SOLUTIONS USING THE TWO-BOTTLE CHOICE TEST ON PND 21-34 AND PND 86-99. BPA EXPOSURE: 1) DECREASED MATERNAL BEHAVIOR IN F1 DAMS, 2) CAUSED DEVELOPMENTAL DEFECTS IN BOTH F1 AND F2 OFFSPRING, WITH A NOTICEABLE DECREASE IN ANOGENITAL DISTANCE IN MALE RATS, AND 3) DID NOT AFFECT FLAVORED SOLUTION INTAKE IN F1, BUT INDUCED CHANGES IN SWEET PREFERENCE IN F2 JUVENILES AND IN SALT AND FAT SOLUTION INTAKES IN F2 ADULTS, AND 4) INDUCED A BODY WEIGHT INCREASE IN THE F2 GENERATION ONLY, WHEREAS FOOD INTAKE AND WATER CONSUMPTION DID NOT CHANGE. TAKEN AS A WHOLE, OUR FINDINGS SHOWED THAT BOTH GESTATIONAL (F0) AND LIFELONG (F1) EXPOSURES TO A HUMAN-RELEVANT DOSE OF BPA COULD INDUCE MULTI-GENERATIONAL EFFECTS ON BOTH DEVELOPMENT AND BEHAVIOR. THESE RESULTS SUGGEST POSSIBLE SELECTIVE NEUROENDOCRINE DEFECTS AND/OR EPIGENETIC CHANGES CAUSED BY BPA EXPOSURE. 2014 4 6894 31 [SOCIAL INEQUALITY AND MENTAL HEALTH]. SOCIAL INEQUALITY REFERS TO THE INEQUITABLE DISTRIBUTION OF SOCIAL PROSPERITY INCLUDING THE RESOURCE OF HEALTH. THE RELATIONSHIP BETWEEN SOCIAL INEQUALITY AND MENTAL HEALTH CAN BE ESTABLISHED BY MEANS OF INDICATORS OF SOCIAL INEQUALITY THROUGHOUT ALL AGE GROUPS IN GERMANY. THERE ARE SOCIAL GRADIENTS OF MENTAL HEALTH ON THE POPULATION LEVEL, I.E. THE LINEAR RELATIONSHIP BETWEEN SOCIAL CLASSES OR STATUS AND STATE OF HEALTH. FUNDAMENTAL DETERMINANTS OF HEALTH DISPARITY ARE CULTURAL, SOCIAL, POLITICAL, AND GEOGRAPHICAL CONDITIONS, WHICH INTERACT WITH THE GENETIC MAKE-UP AND EPIGENETIC PROCESSES. THESE DETERMINANTS ALSO INFLUENCE THE MANAGEMENT OF DEVELOPMENTAL TASKS DURING THE LIFE COURSE AND ARE OF UTMOST IMPORTANCE FOR THE DEVELOPMENT OF MENTAL DISORDERS. THE MALADAPTATION TO CHRONIC STRESS IS AT THE CORE OF HEALTH DISPARITY. INTERVENTIONS AT THE INDIVIDUAL BEHAVIORAL LEVEL SHOULD COMPRISE THE DEVELOPMENT OF STRESS MANAGEMENT AND COPING STRATEGIES. 2019 5 4939 32 PATERNAL NICOTINE EXPOSURE IN RATS PRODUCES LONG-LASTING NEUROBEHAVIORAL EFFECTS IN THE OFFSPRING. STUDIES OF INTERGENERATIONAL EFFECTS OF PARENTAL CHEMICAL EXPOSURE HAVE PRINCIPALLY FOCUSED ON MATERNAL EXPOSURE, PARTICULARLY FOR STUDIES OF ADVERSE NEUROBEHAVIORAL CONSEQUENCES ON THE OFFSPRING. MATERNAL NICOTINE EXPOSURE HAS LONG BEEN KNOWN TO CAUSE ADVERSE NEUROBEHAVIORAL EFFECTS ON THE OFFSPRING. HOWEVER, PATERNAL TOXICANT EXPOSURE HAS ALSO BEEN FOUND TO CAUSE NEUROBEHAVIORAL TOXICITY IN THEIR OFFSPRING. RECENT WORK SUGGESTS THAT PATERNAL NICOTINE EXPOSURE CAN HAVE EPIGENETIC EFFECTS, ALTHOUGH IT REMAINS UNCLEAR WHETHER SUCH CHANGES LEAD TO NEUROBEHAVIORAL EFFECTS. IN THE CURRENT STUDY, WE INVESTIGATED THE EFFECTS OF PATERNAL NICOTINE EXPOSURE ON NEUROBEHAVIORAL DEVELOPMENT OF THEIR OFFSPRING. MALE SPRAGUE-DAWLEY RATS WERE EXPOSED TO 0 OR 2 MG/KG/DAY NICOTINE (SC) FOR 56 CONSECUTIVE DAYS WITH TWO CONSECUTIVE 2ML4 OSMOTIC MINIPUMPS. FOLLOWING TREATMENT, THESE MALES WERE MATED WITH DRUG-NAIVE FEMALE RATS. OFFSPRING OF BOTH SEXES WERE TESTED IN A BEHAVIORAL BATTERY TO ASSESS LOCOMOTION, EMOTIONAL FUNCTION AND COGNITION. PATERNAL NICOTINE EXPOSURE DID NOT IMPACT OFFSPRING VIABILITY, HEALTH OR GROWTH. HOWEVER, BEHAVIORAL FUNCTION OF THE OFFSPRING WAS SIGNIFICANTLY ALTERED BY PATERNAL NICOTINE EXPOSURE. MALE OFFSPRING WITH PATERNAL NICOTINE EXPOSURE EXHIBITED LOCOMOTOR HYPERACTIVITY IN THE FIGURE-8 APPARATUS WHEN TESTED DURING ADOLESCENCE. WHEN RETESTED IN ADULTHOOD AND REGARDLESS OF SEX, OFFSPRING OF THE NICOTINE EXPOSED FATHER SHOWED SIGNIFICANTLY REDUCED HABITUATION OF LOCOMOTOR ACTIVITY OVER THE COURSE OF THE SESSION. COMPARED TO CONTROLS, FEMALE OFFSPRING OF NICOTINE-EXPOSED FATHERS SHOWED SIGNIFICANTLY REDUCED RESPONSE LATENCY IN THE RADIAL ARM MAZE TEST. IN ADDITION TO LOCOMOTOR HYPERACTIVITY, THE OFFSPRING OF NICOTINE-EXPOSED FATHERS ALSO SHOWED SIGNIFICANTLY DIMINISHED HABITUATION IN THE NOVEL OBJECT RECOGNITION TEST. THESE RESULTS INDICATE THAT CHRONIC PATERNAL NICOTINE EXPOSURE CAN IMPACT THE BEHAVIOR OF OFFSPRING, PRODUCING LOCOMOTOR HYPERACTIVITY AND IMPAIRED HABITUATION. 2019 6 4949 31 PATERNAL TRANSMISSION OF STRESS-INDUCED PATHOLOGIES. BACKGROUND: THERE HAS BEEN RECENT INTEREST IN THE POSSIBILITY THAT EPIGENETIC MECHANISMS MIGHT CONTRIBUTE TO THE TRANSGENERATIONAL TRANSMISSION OF STRESS-INDUCED VULNERABILITY. HERE, WE FOCUSED ON POSSIBLE PATERNAL TRANSMISSION WITH THE SOCIAL DEFEAT STRESS PARADIGM. METHODS: ADULT MALE MICE EXPOSED TO CHRONIC SOCIAL DEFEAT STRESS OR CONTROL NONDEFEATED MICE WERE BRED WITH NORMAL FEMALE MICE, AND THEIR OFFSPRING WERE ASSESSED BEHAVIORALLY FOR DEPRESSIVE- AND ANXIETY-LIKE MEASURES. PLASMA LEVELS OF CORTICOSTERONE AND VASCULAR ENDOTHELIAL GROWTH FACTOR WERE ALSO ASSAYED. TO DIRECTLY ASSESS THE ROLE OF EPIGENETIC MECHANISMS, WE USED IN VITRO FERTILIZATION (IVF); BEHAVIORAL ASSESSMENTS WERE CONDUCTED ON OFFSPRING OF MICE FROM IVF-CONTROL AND IVF-DEFEATED FATHERS. RESULTS: WE SHOW THAT BOTH MALE AND FEMALE OFFSPRING FROM DEFEATED FATHERS EXHIBIT INCREASED MEASURES OF SEVERAL DEPRESSION- AND ANXIETY-LIKE BEHAVIORS. THE MALE OFFSPRING OF DEFEATED FATHERS ALSO DISPLAY INCREASED BASELINE PLASMA LEVELS OF CORTICOSTERONE AND DECREASED LEVELS OF VASCULAR ENDOTHELIAL GROWTH FACTOR. HOWEVER, MOST OF THESE BEHAVIORAL CHANGES WERE NOT OBSERVED WHEN OFFSPRING WERE GENERATED THROUGH IVF. CONCLUSIONS: THESE RESULTS SUGGEST THAT, ALTHOUGH BEHAVIORAL ADAPTATIONS THAT OCCUR AFTER CHRONIC SOCIAL DEFEAT STRESS CAN BE TRANSMITTED FROM THE FATHER TO HIS MALE AND FEMALE F1 PROGENY, ONLY VERY SUBTLE CHANGES MIGHT BE TRANSMITTED EPIGENETICALLY UNDER THE CONDITIONS TESTED. 2011 7 4937 33 PATERNAL MORPHINE EXPOSURE IN RATS REDUCES SOCIAL PLAY IN ADOLESCENT MALE PROGENY WITHOUT AFFECTING DRUG-TAKING BEHAVIOR IN JUVENILE MALES OR FEMALE OFFSPRING. THE ONGOING OPIOID ADDICTION CRISIS NECESSITATES THE IDENTIFICATION OF NOVEL RISK FACTORS TO IMPROVE PREVENTION AND TREATMENT OF OPIOID USE DISORDER. PARENTAL OPIOID EXPOSURE HAS RECENTLY EMERGED AS A POTENTIAL REGULATOR OF OFFSPRING VULNERABILITY TO OPIOID MISUSE, IN ADDITION TO HERITABLE GENETIC LIABILITY. AN UNDERSTUDIED ASPECT OF THIS "MISSING HERITABILITY" IS THE DEVELOPMENTAL PRESENTATION OF THESE CROSS-GENERATIONAL PHENOTYPES. THIS IS AN ESPECIALLY RELEVANT QUESTION IN THE CONTEXT OF INHERITED ADDICTION-RELATED PHENOTYPES, GIVEN THE PROMINENT ROLE OF DEVELOPMENTAL PROCESSES IN THE ETIOLOGY OF PSYCHIATRIC DISORDERS. PATERNAL MORPHINE SELF-ADMINISTRATION WAS PREVIOUSLY SHOWN TO ALTER THE SENSITIVITY TO THE REINFORCING AND ANTINOCICEPTIVE PROPERTIES OF OPIOIDS IN THE NEXT GENERATION. HERE, PHENOTYPING WAS EXPANDED TO INCLUDE THE ADOLESCENT PERIOD, WITH A FOCUS ON ENDOPHENOTYPES RELATED TO OPIOID USE DISORDERS AND PAIN. PATERNAL MORPHINE EXPOSURE DID NOT ALTER HEROIN OR COCAINE SELF-ADMINISTRATION IN MALE AND FEMALE JUVENILE PROGENY. FURTHER, BASELINE SENSORY REFLEXES RELATED TO PAIN WERE UNALTERED IN MORPHINE-SIRED ADOLESCENT RATS OF EITHER SEX. HOWEVER, MORPHINE-SIRED ADOLESCENT MALES EXHIBITED A REDUCTION IN SOCIAL PLAY BEHAVIOR. OUR FINDINGS SUGGEST THAT, IN MORPHINE-SIRED MALE OFFSPRING, PATERNAL OPIOID EXPOSURE DOES NOT AFFECT OPIOID INTAKE DURING ADOLESCENCE, SUGGESTING THAT THIS PHENOTYPE DOES NOT EMERGE UNTIL LATER IN LIFE. ALTERED SOCIAL BEHAVIORS IN MALE MORPHINE-SIRED ADOLESCENTS INDICATE THAT THE CHANGES IN DRUG-TAKING BEHAVIOR IN ADULTS SIRED BY MORPHINE-EXPOSED SIRES MAY BE DUE TO MORE COMPLEX FACTORS NOT YET FULLY ASSESSED. 2023 8 1005 34 CHRONIC VARIABLE PHYSICAL STRESS DURING THE PERIPUBERTAL-JUVENILE PERIOD CAUSES DIFFERENTIAL DEPRESSIVE AND ANXIOGENIC EFFECTS IN THE NOVELTY-SEEKING PHENOTYPE: FUNCTIONAL IMPLICATIONS FOR HIPPOCAMPAL AND AMYGDALAR BRAIN-DERIVED NEUROTROPHIC FACTOR AND THE MOSSY FIBRE PLASTICITY. EXPERIMENTALLY NAIVE RATS SHOW VARIANCE IN THEIR LOCOMOTOR REACTIVITY TO NOVELTY, SOME DISPLAYING HIGHER (HR) WHILE OTHERS DISPLAYING LOWER (LR) REACTIVITY, ASSOCIATED WITH VULNERABILITY TO STRESS. WE EMPLOYED A CHRONIC VARIABLE PHYSICAL STRESS REGIMEN INCORPORATING INTERMITTENT AND RANDOM EXPOSURES OF PHYSICAL STRESSORS OR CONTROL HANDLING DURING THE PERIPUBERTAL-JUVENILE PERIOD TO ASSESS INTERACTIONS BETWEEN STRESS AND THE LRHR PHENOTYPE IN DEPRESSIVE- AND ANXIETY-LIKE BEHAVIORS ON THE FORCED SWIM AND SOCIAL INTERACTION TESTS, RESPECTIVELY. A DECREASE IN IMMOBILITY IN THE FORCED SWIM TEST ALONG WITH A DECREASE IN SOCIAL CONTACT IN THE SOCIAL INTERACTION TEST WERE OBSERVED IN THE JUVENILE HRS, COUPLED WITH INCREASES IN BRAIN-DERIVED NEUROTROPHIC FACTOR (BDNF) MRNA IN THE HIPPOCAMPUS AND IN THE BASOLATERAL AMYGDALA WITH CHRONIC VARIABLE PHYSICAL STRESS. IN CONTRAST, AN INCREASE IN IMMOBILITY IN THE FORCED SWIM TEST AND A DECREASE IN SOCIAL CONTACT WAS OBSERVED IN THE LR COUNTERPARTS COUPLED WITH AN INCREASE IN THE BDNF MRNA IN THE BASOLATERAL AMYGDALA FOLLOWING CHRONIC VARIABLE PHYSICAL STRESS. FURTHERMORE, CHRONIC PHYSICAL STRESS LED TO INCREASED H3 AND H4 ACETYLATION AT THE P2 AND P4 PROMOTERS OF THE HIPPOCAMPAL BDNF GENE IN THE HR RATS THAT IS ASSOCIATED WITH INCREASED SUPRAPYRAMIDAL MOSSY FIBRE (SP-MF) TERMINAL FIELD VOLUME. IN CONTRAST, CHRONIC VARIABLE PHYSICAL STRESS LED TO DECREASED H4 ACETYLATION AT THE P4 PROMOTER, ASSOCIATED WITH DECREASED SP-MF VOLUME IN THE LR RATS. THESE FINDINGS SHOW DISSOCIATION IN DEPRESSIVE- AND ANXIETY-LIKE BEHAVIORS FOLLOWING CHRONIC VARIABLE PHYSICAL STRESS IN THE JUVENILE HR ANIMALS THAT MAY BE MEDIATED BY INCREASED LEVELS OF BDNF IN THE HIPPOCAMPUS AND IN THE AMYGDALA, RESPECTIVELY. MOREOVER, CHRONIC VARIABLE PHYSICAL STRESS DURING THE PERIPUBERTAL-JUVENILE PERIOD RESULTS IN OPPOSITE EFFECTS IN DEPRESSIVE-LIKE BEHAVIOR IN THE LRHR RATS BY WAY OF INDUCING DIFFERENTIAL EPIGENETIC REGULATION OF THE HIPPOCAMPAL BDNF GENE THAT, IN TURN, MAY MEDIATE MOSSY FIBRE SPROUTING. 2011 9 5538 20 ROLE OF CHRONIC ALCOHOLISM CAUSING CANCER IN OMNIVORES AND VEGETARIANS THROUGH EPIGENETIC MODIFICATIONS. ONE OF THE SIGNIFICANT CONSEQUENCES OF ALCOHOL CONSUMPTION IS CANCER FORMATION VIA SEVERAL CONTRIBUTING FACTORS SUCH AS ACTION OF ALCOHOL METABOLITES, VITAMIN DEFICIENCIES, AND OXIDATIVE STRESS. ALL THESE FACTORS HAVE BEEN SHOWN TO CAUSE EPIGENETIC MODIFICATIONS VIA DNA HYPOMETHYLATION, THUS FORMING A BASIS FOR CANCER DEVELOPMENT. SEVERAL PUBLISHED REVIEWS AND STUDIES WERE SYSTEMATICALLY REVIEWED. OMNIVORES AND VEGETARIANS DIFFER IN TERMS OF NUTRITIONAL INTAKE AND DEFICIENCIES. AS FOLATE DEFICIENCY WAS FOUND TO BE COMMON AMONG THE OMNIVORES, CHRONIC ALCOHOLISM COULD POSSIBLY CAUSE DAMAGE AND EVENTUALLY CANCER IN AN OMNIVOROUS INDIVIDUAL VIA DNA HYPOMETHYLATION DUE TO FOLATE DEFICIENCY. FURTHERMORE, AS NIACIN WAS FOUND TO BE DEFICIENT AMONG VEGETARIANS, DAMAGE IN VEGETARIAN CHRONIC ALCOHOLICS COULD BE DUE TO INCREASED NADH/NAD (+) RATIO, THUS SLOWING ALCOHOL METABOLISM IN LIVER LEADING TO INCREASED ALCOHOL AND ACETALDEHYDE WHICH INHIBIT METHYLTRANSFERASE ENZYMES, EVENTUALLY LEADING TO DNA HYPOMETHYLATION. HENCE CORRECTING THE CONCERNED DEFICIENCY AND SUPPLEMENTATION WITH S-ADENOSYL METHIONINE COULD PROVE TO BE PROTECTIVE IN CHRONIC ALCOHOL USE. 2020 10 5008 35 PERIPUBERTAL STRESS WITH SOCIAL SUPPORT PROMOTES RESILIENCE IN THE FACE OF AGING. THE PERIPUBERTAL PERIOD OF DEVELOPMENT IS A SENSITIVE WINDOW, DURING WHICH ADVERSE EXPERIENCES CAN INCREASE THE RISK FOR PRESENTATION OF COGNITIVE AND AFFECTIVE DYSFUNCTION THROUGHOUT THE LIFESPAN, ESPECIALLY IN WOMEN. HOWEVER, SUCH EXPERIENCES IN THE CONTEXT OF A SUPPORTIVE SOCIAL ENVIRONMENT CAN ACTUALLY AMELIORATE THIS RISK, SUGGESTING THAT RESILIENCE CAN BE PROGRAMMED IN EARLY LIFE. AFFECTIVE DISORDERS AND COGNITIVE DEFICITS COMMONLY EMERGE DURING AGING, WITH MANY WOMEN REPORTING INCREASED DIFFICULTY WITH PREFRONTAL CORTEX (PFC)-DEPENDENT EXECUTIVE FUNCTIONS. WE HAVE DEVELOPED A MOUSE MODEL TO EXAMINE THE INTERACTION BETWEEN PERIPUBERTAL EXPERIENCE AND AGE-RELATED CHANGES IN COGNITION AND STRESS REGULATION. FEMALE MICE WERE EXPOSED TO PERIPUBERTAL CHRONIC STRESS, DURING WHICH THEY WERE EITHER INDIVIDUALLY HOUSED OR HOUSED WITH SOCIAL INTERACTION. ONE YEAR AFTER THIS STRESS EXPERIENCE, MICE WERE EXAMINED IN TASKS TO ACCESS THEIR COGNITIVE ABILITY AND FLEXIBILITY IN STRESS REACTIVE MEASURES. IN A TEST OF SPATIAL MEMORY ACQUISITION AND REVERSAL LEARNING WHERE AGED FEMALES NORMALLY DISPLAY A DECREASED PERFORMANCE, THE FEMALES THAT HAD EXPERIENCED STRESS WITH SOCIAL INTERACTION A YEAR EARLIER SHOWED IMPROVED PERFORMANCE IN REVERSAL LEARNING, A MEASURE OF COGNITIVE FLEXIBILITY. BECAUSE PERIPUBERTY IS A TIME OF MAJOR PFC MATURATION, WE PERFORMED TRANSCRIPTOMIC AND BIOCHEMICAL ANALYSIS OF THE AGED PFC, IN WHICH LONG-TERM CHANGES IN MICRORNA EXPRESSION AND IN MYELIN PROTEINS WERE FOUND. THESE DATA SUGGEST THAT STRESS IN THE CONTEXT OF SOCIAL SUPPORT EXPERIENCED OVER THE PUBERTAL WINDOW CAN PROMOTE EPIGENETIC REPROGRAMMING IN THE BRAIN TO INCREASE THE RESILIENCE TO AGE-RELATED COGNITIVE DECLINE IN FEMALES. 2016 11 3713 37 INHERITANCE OF ACQUIRED BEHAVIOUR ADAPTATIONS AND BRAIN GENE EXPRESSION IN CHICKENS. BACKGROUND: ENVIRONMENTAL CHALLENGES MAY AFFECT BOTH THE EXPOSED INDIVIDUALS AND THEIR OFFSPRING. WE INVESTIGATED POSSIBLE ADAPTIVE ASPECTS OF SUCH CROSS-GENERATION TRANSMISSIONS, AND HYPOTHESIZED THAT CHRONIC UNPREDICTABLE FOOD ACCESS WOULD CAUSE CHICKENS TO SHOW A MORE CONSERVATIVE FEEDING STRATEGY AND TO BE MORE DOMINANT, AND THAT THESE ADAPTATIONS WOULD BE TRANSMITTED TO THE OFFSPRING. METHODOLOGY/PRINCIPAL FINDINGS: PARENTS WERE RAISED IN AN UNPREDICTABLE (UL) OR IN PREDICTABLE DIURNAL LIGHT RHYTHM (PL, 12:12 H LIGHT:DARK). IN A FORAGING TEST, UL BIRDS PECKED MORE AT FREELY AVAILABLE, RATHER THAN AT HIDDEN AND MORE ATTRACTIVE FOOD, COMPARED TO BIRDS FROM THE PL GROUP. FEMALE OFFSPRING OF UL BIRDS, RAISED IN PREDICTABLE LIGHT CONDITIONS WITHOUT PARENTAL CONTACT, SHOWED A SIMILAR FORAGING BEHAVIOR, DIFFERING FROM OFFSPRING OF PL BIRDS. FURTHERMORE, ADULT OFFSPRING OF UL BIRDS PERFORMED MORE FOOD PECKS IN A DOMINANCE TEST, SHOWED A HIGHER PREFERENCE FOR HIGH ENERGY FOOD, SURVIVED BETTER, AND WERE HEAVIER THAN OFFSPRING OF PL PARENTS. USING CDNA MICROARRAYS, WE FOUND THAT THE DIFFERENTIAL BRAIN GENE EXPRESSION CAUSED BY THE CHALLENGE WAS MIRRORED IN THE OFFSPRING. IN PARTICULAR, SEVERAL IMMUNOGLOBULIN GENES SEEMED TO BE AFFECTED SIMILARLY IN BOTH UL PARENTS AND THEIR OFFSPRING. ESTRADIOL LEVELS WERE SIGNIFICANTLY HIGHER IN EGG YOLK FROM UL BIRDS, SUGGESTING ONE POSSIBLE MECHANISM FOR THESE EFFECTS. CONCLUSIONS/SIGNIFICANCE: OUR FINDINGS SUGGEST THAT UNPREDICTABLE FOOD ACCESS CAUSED SEEMINGLY ADAPTIVE RESPONSES IN FEEDING BEHAVIOR, WHICH MAY HAVE BEEN TRANSMITTED TO THE OFFSPRING BY MEANS OF EPIGENETIC MECHANISMS, INCLUDING REGULATION OF IMMUNE GENES. THIS MAY HAVE PREPARED THE OFFSPRING FOR COPING WITH AN UNPREDICTABLE ENVIRONMENT. 2009 12 5786 35 SPORT AND MALE SEXUALITY. THE RELATIONSHIPS BETWEEN SPORT AND SEXUALITY IN MALES ARE OF GREAT SOCIAL AND CLINICAL INTEREST, BECAUSE OF SPORTS AND MOTOR ACTIVITIES THAT HIGHLY PROMOTE SOCIAL AND SEXUAL RELATIONSHIPS. EVEN IF FEW LITERATURE EXIST, TWO MAIN QUESTIONS SHOULD BE TAKEN INTO ACCOUNT: WHETHER AND HOW PHYSICAL EXERCISE AND SPORT POSITIVELY OR NEGATIVELY INFLUENCE SEXUAL HEALTH AND BEHAVIOR AND/OR WHETHER AND HOW SEXUAL BEHAVIOR MAY AFFECT A SUB-SEQUENT SPORT PERFORMANCE. PHYSICAL EXERCISE AND SPORT PER SE CAN INFLUENCE, POSITIVELY OR NEGATIVELY, THE HYPOTHALAMIC-PITUITARY-TESTICULAR AXIS FUNCTION AND, CONSEQUENTLY, THE INDIVIDUAL'S REPRODUCTIVE AND/OR SEXUAL HEALTH. THIS DEPENDS ON INDIVIDUAL FACTORS SUCH AS GENETIC AND EPIGENETIC ONES AND ON DIFFERENT VARIABLES INVOLVED IN THE PRACTICE OF SPORT ACTIVITIES (TYPE OF SPORT, INTENSITY AND DURATION OF TRAINING, DOPING AND DRUG USE AND ABUSE, NUTRITION, SUPPLEMENTS, PSYCHOLOGICAL STRESS, ALLOSTATIC LOAD, ETC.). IF WELL CONDUCTED, MOTOR AND SPORT ACTIVITIES COULD HAVE BENEFICIAL EFFECTS ON SEXUAL HEALTH IN MALES. AMONG DIFFERENT LIFESTYLE CHANGES, INFLUENCING SEXUAL HEALTH, REGULAR PHYSICAL ACTIVITY IS FUNDAMENTAL TO ANTAGONIZE THE ONSET OF ERECTILE DYSFUNCTION (ED). HOWEVER, COMPETITIVE SPORT CAN LEAD BOTH REPRODUCTIVE AND/OR SEXUAL TRACT DAMAGES AND DYSFUNCTIONS, TRANSIENT (GENITAL PAIN, HYPOESTHESIA OF THE GENITALIA, HYPOGONADISM, DE, ALTERED SEXUAL DRIVE, ETC.) OR PERMANENT (HYPOGONADISM, DE, ETC.), BY ACTING DIRECTLY (TRAUMAS OF THE EXTERNAL GENITALIA, SADDLE-RELATED DISORDERS IN CYCLISTS, ETC.) OR INDIRECTLY (EXERCISE-RELATED HYPOGONADISM, DRUG ABUSE, DOPING, STRESS, ETC.). SEXUAL ACTIVITIES SHORTLY PERFORMED BEFORE A SPORT COMPETITION COULD DIFFERENTLY INFLUENCE SPORT PERFORMANCE. DUE TO THE FEW EXISTING DATA, IT IS ADVISABLE TO AVOID AN ABSOLUTE PRE-COMPETITION SEXUAL ABSTINENCE. 2017 13 4938 21 PATERNAL NICOTINE ENHANCES FEAR MEMORY, REDUCES NICOTINE ADMINISTRATION, AND ALTERS HIPPOCAMPAL GENETIC AND NEURAL FUNCTION IN OFFSPRING. NICOTINE USE REMAINS HIGHLY PREVALENT WITH TOBACCO AND E-CIGARETTE PRODUCTS CONSUMED WORLDWIDE. HOWEVER, INCREASING EVIDENCE OF TRANSGENERATIONAL EPIGENETIC INHERITANCE SUGGESTS THAT NICOTINE USE MAY ALTER BEHAVIOR AND NEUROBIOLOGY IN SUBSEQUENT GENERATIONS. WE TESTED THE EFFECTS OF CHRONIC PATERNAL NICOTINE EXPOSURE IN C57BL6/J MICE ON FEAR CONDITIONING IN F1 AND F2 OFFSPRING, AS WELL AS CONDITIONED FEAR EXTINCTION AND SPONTANEOUS RECOVERY, NICOTINE SELF-ADMINISTRATION, HIPPOCAMPAL CHOLINERGIC FUNCTIONING, RNA EXPRESSION, AND DNA METHYLATION IN F1 OFFSPRING. PATERNAL NICOTINE EXPOSURE WAS ASSOCIATED WITH ENHANCED CONTEXTUAL AND CUED FEAR CONDITIONING AND SPONTANEOUS RECOVERY OF EXTINGUISHED FEAR MEMORIES. FURTHER, NICOTINE REINFORCEMENT WAS REDUCED IN NICOTINE-SIRED MICE, AS ASSESSED IN A SELF-ADMINISTRATION PARADIGM. THESE BEHAVIORAL PHENOTYPES WERE COUPLED WITH ALTERED RESPONSE TO NICOTINE, UPREGULATED HIPPOCAMPAL NICOTINIC ACETYLCHOLINE RECEPTOR BINDING, REDUCED EVOKED HIPPOCAMPAL CHOLINERGIC CURRENTS, AND ALTERED METHYLATION AND EXPRESSION OF HIPPOCAMPAL GENES RELATED TO NEURAL DEVELOPMENT AND PLASTICITY. GENE EXPRESSION ANALYSIS SUGGESTS MULTIGENERATIONAL EFFECTS ON BROADER GENE NETWORKS POTENTIALLY INVOLVED IN NEUROPLASTICITY AND MENTAL DISORDERS. THE CHANGES IN FEAR CONDITIONING SIMILARLY SUGGEST PHENOTYPES ANALOGOUS TO ANXIETY DISORDERS SIMILAR TO POST-TRAUMATIC STRESS. 2021 14 5311 39 PSYCHOLOGICAL AND BIOLOGICAL RESILIENCE MODULATES THE EFFECTS OF STRESS ON EPIGENETIC AGING. OUR SOCIETY IS EXPERIENCING MORE STRESS THAN EVER BEFORE, LEADING TO BOTH NEGATIVE PSYCHIATRIC AND PHYSICAL OUTCOMES. CHRONIC STRESS IS LINKED TO NEGATIVE LONG-TERM HEALTH CONSEQUENCES, RAISING THE POSSIBILITY THAT STRESS IS RELATED TO ACCELERATED AGING. IN THIS STUDY, WE EXAMINE WHETHER RESILIENCE FACTORS AFFECT STRESS-ASSOCIATED BIOLOGICAL AGE ACCELERATION. RECENTLY DEVELOPED "EPIGENETIC CLOCKS" SUCH AS GRIMAGE HAVE SHOWN UTILITY IN PREDICTING BIOLOGICAL AGE AND MORTALITY. HERE, WE ASSESSED THE IMPACT OF CUMULATIVE STRESS, STRESS PHYSIOLOGY, AND RESILIENCE ON ACCELERATED AGING IN A COMMUNITY SAMPLE (N = 444). CUMULATIVE STRESS WAS ASSOCIATED WITH ACCELERATED GRIMAGE (P = 0.0388) AND STRESS-RELATED PHYSIOLOGIC MEASURES OF ADRENAL SENSITIVITY (CORTISOL/ACTH RATIO) AND INSULIN RESISTANCE (HOMA). AFTER CONTROLLING FOR DEMOGRAPHIC AND BEHAVIORAL FACTORS, HOMA CORRELATED WITH ACCELERATED GRIMAGE (P = 0.0186). REMARKABLY, PSYCHOLOGICAL RESILIENCE FACTORS OF EMOTION REGULATION AND SELF-CONTROL MODERATED THESE RELATIONSHIPS. EMOTION REGULATION MODERATED THE ASSOCIATION BETWEEN STRESS AND AGING (P = 8.82E-4) SUCH THAT WITH WORSE EMOTION REGULATION, THERE WAS GREATER STRESS-RELATED AGE ACCELERATION, WHILE STRONGER EMOTION REGULATION PREVENTED ANY SIGNIFICANT EFFECT OF STRESS ON GRIMAGE. SELF-CONTROL MODERATED THE RELATIONSHIP BETWEEN STRESS AND INSULIN RESISTANCE (P = 0.00732), WITH HIGH SELF-CONTROL BLUNTING THIS RELATIONSHIP. IN THE FINAL MODEL, IN THOSE WITH POOR EMOTION REGULATION, CUMULATIVE STRESS CONTINUED TO PREDICT ADDITIONAL GRIMAGE ACCELERATION EVEN WHILE ACCOUNTING FOR DEMOGRAPHIC, PHYSIOLOGIC, AND BEHAVIORAL COVARIATES. THESE RESULTS DEMONSTRATE THAT CUMULATIVE STRESS IS ASSOCIATED WITH EPIGENETIC AGING IN A HEALTHY POPULATION, AND THESE ASSOCIATIONS ARE MODIFIED BY BIOBEHAVIORAL RESILIENCE FACTORS. 2021 15 4402 30 MODULATION OF NOCICEPTION BY SOCIAL FACTORS IN RODENTS: CONTRIBUTION OF THE OPIOID SYSTEM. RATIONALE: THE OPIOID SYSTEM IS INVOLVED IN THE REGULATION OF SEVERAL BEHAVIORAL AND PHYSIOLOGICAL RESPONSES, CONTROLLING PAIN, REWARD, AND ADDICTIVE BEHAVIORS. OPIOID ADMINISTRATION, DEPENDING ON DRUGS AND DOSES, USUALLY AFFECTS SOCIABILITY REDUCING INTERACTIONS BETWEEN CONSPECIFICS, WHEREAS SOME AFFILIATIVE BEHAVIORS SUCH AS SEXUAL ACTIVITY, SOCIAL GROOMING, AND PLAY BEHAVIOR INCREASE THE ENDOGENOUS OPIOID ACTIVITY. OBJECTIVES: THE POSSIBLE INTERACTION BETWEEN ENDOGENOUS OPIOIDS RELEASED DURING SOCIO/SEXUAL BEHAVIOR AND THEIR ANALGESIC EFFECT ON PAIN RESPONSE IS REVIEWED IN THE RODENT LITERATURE. RESULTS: DIRECT EVIDENCE FOR SOCIALLY MEDIATED OPIOID CHANGES RESULTING IN INCREASE IN NOCICEPTIVE THRESHOLD DERIVES FROM STUDIES EXPLORING THE EFFECTS OF DEFEAT EXPERIENCES, SOCIAL ISOLATION, MATERNAL, SEXUAL BEHAVIOR, AND SOCIAL REUNION AMONG KIN OR FAMILIAR ANIMALS IN LABORATORY RODENTS. INDIRECT EVIDENCE FOR ENDOGENOUS ACTIVATION OF THE OPIOID SYSTEM, POSSIBLY AFFECTING PAIN SENSITIVITY, DERIVES FROM STUDIES INVESTIGATING THE RELEVANCE OF NATURAL SOCIAL REWARD USING THE CONDITIONED PLACE PREFERENCE PROTOCOLS OR ANALYZING ULTRASONIC VOCALIZATIONS ASSOCIATED TO POSITIVE AFFECTIVE CONTEXTS. FINALLY, GENETIC AND EPIGENETIC FACTORS THAT AFFECT THE OPIOID SYSTEM DURING DEVELOPMENT ARE REPORTED TO BE INVOLVED IN MODULATING THE RESPONSE TO SOCIAL STIMULI AS WELL AS NOCICEPTION. CONCLUSIONS: ALL STUDIES HIGHLIGHT THE RELEVANCE OF AFFILIATIVE CONTACT BEHAVIOR BETWEEN CONSPECIFICS THAT IS RESPONSIBLE FOR THE ACTIVATION OF THE ENDOGENOUS MU-OPIOID SYSTEM, INDUCING NOCICEPTIVE THRESHOLD INCREASE. 2012 16 5465 36 RESILIENCE TO STRESS: LESSONS FROM RODENTS ABOUT NATURE VERSUS NURTURE. INDIVIDUAL DIFFERENCES IN HUMAN TEMPERAMENT INFLUENCE HOW WE RESPOND TO STRESS AND CAN CONFER VULNERABILITY (OR RESILIENCE) TO EMOTIONAL DISORDERS. FOR EXAMPLE, HIGH LEVELS OF BEHAVIORAL INHIBITION IN CHILDREN PREDICT INCREASED RISK OF MOOD AND ANXIETY DISORDERS IN LATER LIFE. THE BIOLOGICAL UNDERPINNINGS OF TEMPERAMENT ARE UNKNOWN, ALTHOUGH IMPROVED UNDERSTANDING CAN OFFER INSIGHT INTO THE PATHOGENESIS OF EMOTIONAL DISORDERS. OUR LABORATORY HAS USED A RAT MODEL OF TEMPERAMENTAL DIFFERENCES TO STUDY NEURODEVELOPMENTAL FACTORS THAT LEAD TO A HIGHLY INHIBITED, STRESS VULNERABLE PHENOTYPE. SELECTIVE BREEDING FOR HIGH VERSUS LOW BEHAVIORAL RESPONSE TO NOVELTY CREATED TWO RAT STRAINS THAT EXHIBIT DRAMATIC BEHAVIOR DIFFERENCES OVER MULTIPLE DOMAINS RELEVANT TO EMOTIONAL DISORDERS. LOW NOVELTY RESPONDER (BLR) RATS EXHIBIT HIGH LEVELS OF BEHAVIORAL INHIBITION, PASSIVE STRESS COPING, ANHEDONIA, DECREASED SOCIABILITY AND VULNERABILITY TO CHRONIC STRESS COMPARED TO HIGH NOVELTY RESPONDERS (BHRS). ON THE OTHER HAND, BHRS EXHIBIT HIGH LEVELS OF BEHAVIORAL DIS-INHIBITION, ACTIVE COPING, AND AGGRESSION. THIS REVIEW ARTICLE SUMMARIZES OUR WORK WITH THE BHR/BLR MODEL SHOWING THE DEVELOPMENTAL EMERGENCE OF THE BHR/BLR PHENOTYPES, THE ROLE THE ENVIRONMENT PLAYS IN SHAPING IT, AND THE INVOLVEMENT OF EPIGENETIC PROCESSES SUCH AS DNA METHYLATION THAT MEDIATE DIFFERENCES IN EMOTIONALITY AND STRESS REACTIVITY. 2022 17 5077 31 PHYSIOLOGICAL PATHWAYS TO RAPID PROSOCIAL EVOLUTION. DOGS (CANIS LUPUS FAMILIARIS) DESCEND FROM WOLVES (CANIS LUPUS) SHARING THE SAME ECOLOGICAL NICHE OF COOPERATIVE HUNTERS, AS HUMANS. INITIALLY, HUMANS AND WOLVES WERE COMPETITORS STARTING INTERSPECIFIC COMMUNICATION IN ORDER TO AVOID RISK OF INJURY. THE EVOLUTIONARY CONTINUITY OF MAMMALIAN BRAINS ENABLED INTERSPECIFIC PROSOCIAL CONTACTS BETWEEN BOTH OF THEM, WHICH REDUCED STRESS, AND ENABLED BEHAVIORAL CULTURES LEADING TO GENETIC ISOLATION OF THOSE WOLVES. DOGS ARE THE FIRST DOMESTICATED ANIMAL LIVING TOGETHER WITH HUMANS FOR ABOUT 25,000 YEARS. DOMESTICATION MEANS DECREASED AGGRESSION AND FLIGHT DISTANCE TOWARD HUMANS, THUS CHANGES IN THE STRESS AXIS ARE CRUCIAL. THE HYPOTHESIS OF ACTIVE SOCIAL DOMESTICATION CONSIDERS GENETIC SELECTION AS A NECESSARY PREDICTION BUT NOT A SUFFICIENT EXPLANATION OF DOG DOMESTICATION. IN ADDITION, DOG DOMESTICATION IS SUGGESTED TO BE AN EPIGENETIC DISCLOSURE. DUE TO CHANGED STRESS ACTIVITY, EPIGENETIC MECHANISMS AFFECT CEREBRAL RECEPTOR ACTIVITY AND REGULATE TRANSPOSON EXPRESSIONS, THUS SHAPING BRAIN FUNCTION AND BEHAVIOR. INTERSPECIFIC PROSOCIAL CONTACTS INITIATED VIA SEROTONIN RELEASE AN ENZYMATIC CASCADE ENHANCING, EPIGENETI-CALLY, THE GLUCOCORTICOID NEGATIVE FEEDBACK LOOP. REDUCED CHRONIC STRESS IMPROVED SOCIAL LEARNING CAPABILITY AND INHIBITORY CONTROL. OVER TIME, THOSE WOLVES COULD INTEGRATE THEMSELVES INTO HUMAN SOCIAL STRUCTURES, THUS BECOMING DOGS. IN ANALOGY, HUMAN MENTAL SKILLS, SUCH AS CREATING ART AND CULTURE, MIGHT HAVE ALSO IMPROVED DURING THE UPPER PALEOLITHIC. 2019 18 2949 35 GENETIC AND EPIGENETIC CONSEQUENCE OF EARLY-LIFE SOCIAL STRESS ON DEPRESSION: ROLE OF SEROTONIN-ASSOCIATED GENES. EARLY-LIFE ADVERSITY CAUSED BY POOR SOCIAL BONDING AND DEPRIVED MATERNAL CARE IS KNOWN TO AFFECT MENTAL WELLBEING AND PHYSICAL HEALTH. IT IS A FORM OF CHRONIC SOCIAL STRESS THAT PERSISTS BECAUSE OF A NEGATIVE ENVIRONMENT, AND THE CONSEQUENCES ARE LONG-LASTING ON MENTAL HEALTH. THE PRESENCE OF SOCIAL STRESS DURING EARLY LIFE CAN HAVE AN EPIGENETIC EFFECT ON THE BODY, POSSIBLY RESULTING IN MANY COMPLEX MENTAL DISORDERS, INCLUDING DEPRESSION IN LATER LIFE. HERE, WE REVIEW THE EVIDENCE FOR EARLY-LIFE SOCIAL STRESS-INDUCED EPIGENETIC CHANGES THAT MODULATE JUVENILE AND ADULT SOCIAL BEHAVIOR (DEPRESSION AND ANXIETY). THIS REVIEW HAS A PARTICULAR EMPHASIS ON THE INTERACTION BETWEEN EARLY-LIFE SOCIAL STRESS AND GENETIC VARIATION OF SEROTONIN ASSOCIATE GENES INCLUDING THE SEROTONIN TRANSPORTER GENE (5-HTT; ALSO KNOWN AS SLC6A4), WHICH ARE KEY MOLECULES INVOLVED IN DEPRESSION. 2020 19 4064 36 MATERNAL AND EARLY-LIFE CIRCADIAN DISRUPTION HAVE LONG-LASTING NEGATIVE CONSEQUENCES ON OFFSPRING DEVELOPMENT AND ADULT BEHAVIOR IN MICE. MODERN LIFE INVOLVES CHRONIC CIRCADIAN DISRUPTION THROUGH ARTIFICIAL LIGHT AND THESE DISRUPTIONS ARE ASSOCIATED WITH NUMEROUS MENTAL AND PHYSICAL HEALTH MALADIES. BECAUSE THE DEVELOPING NERVOUS SYSTEM IS PARTICULARLY VULNERABLE TO PERTURBATION, WE HYPOTHESIZED THAT EARLY-LIFE CIRCADIAN DISRUPTION WOULD NEGATIVELY IMPACT OFFSPRING DEVELOPMENT AND ADULT FUNCTION. PREGNANT MICE WERE SUBJECTED TO CHRONIC CIRCADIAN DISRUPTION FROM THE TIME OF UTERINE IMPLANTATION THROUGH WEANING. TO DISSOCIATE IN UTERO FROM POSTNATAL EFFECTS, A SUBSET OF LITTERS WAS CROSS-FOSTERED AT BIRTH FROM DISRUPTED DAMS TO CONTROL DAMS AND VICE VERSA. POSTNATAL CIRCADIAN DISRUPTION WAS ASSOCIATED WITH REDUCED ADULT BODY MASS, SOCIAL AVOIDANCE, AND HYPERACTIVITY. IN UTERO DISRUPTION RESULTED IN MORE PRONOUNCED SOCIAL AVOIDANCE AND HYPERACTIVITY, PHENOTYPES NOT ABROGATED BY CROSS-FOSTERING TO CONTROL MOTHERS. TO EXAMINE WHETHER CIRCADIAN DISRUPTION AFFECTS DEVELOPMENT BY ACTING AS AN EARLY LIFE STRESSOR, WE EXAMINED BIRTHWEIGHT, LITTER SIZE, MATERNAL CANNIBALISM, AND EPIGENETIC MODIFICATIONS. NONE OF THESE VARIABLES DIFFERED BETWEEN CONTROL AND DISRUPTED DAMS, OR RESEMBLED PATTERNS SEEN FOLLOWING EARLY-LIFE STRESS. OUR FINDINGS INDICATE THAT DEVELOPMENTAL CHRONIC CIRCADIAN DISRUPTION PERMANENTLY AFFECTS SOMATIC AND BEHAVIORAL DEVELOPMENT IN A STAGE-OF-LIFE-DEPENDENT MANNER, INDEPENDENT OF EARLY LIFE STRESS MECHANISMS, UNDERSCORING THE IMPORTANCE OF TEMPORAL STRUCTURE DURING DEVELOPMENT, BOTH IN UTERO AND EARLY POSTNATAL LIFE. 2017 20 5466 33 RESILIENCE: SAFETY IN THE AFTERMATH OF TRAUMATIC STRESSOR EXPERIENCES. THE RELATIONSHIP BETWEEN ADVERSE EXPERIENCES AND THE EMERGENCE OF PATHOLOGY HAS OFTEN FOCUSED ON CHARACTERISTICS OF THE STRESSOR OR OF THE INDIVIDUAL (STRESSOR APPRAISALS, COPING STRATEGIES). THESE FEATURES ARE THOUGHT TO INFLUENCE MULTIPLE BIOLOGICAL PROCESSES THAT FAVOR THE DEVELOPMENT OF MENTAL AND PHYSICAL ILLNESSES. LESS OFTEN HAS ATTENTION FOCUSED ON THE AFTERMATH OF TRAUMATIC EXPERIENCES, AND THE IMPORTANCE OF SAFETY AND REASSURANCE THAT IS NECESSARY FOR LONGER-TERM WELL-BEING. IN SOME CASES (E.G., POST-TRAUMATIC STRESS DISORDER) THIS MAY BE REFLECTED BY A FAILURE OF FEAR EXTINCTION, WHEREAS IN OTHER INSTANCES (E.G., HISTORICAL TRAUMA), THE UNCERTAINTY ABOUT THE FUTURE MIGHT FOSTER CONTINUED ANXIETY. IN ESSENCE, THE QUESTION BECOMES ONE OF HOW INDIVIDUALS ATTAIN FEELINGS OF SAFETY WHEN IT IS FULLY UNDERSTOOD THAT THE WORLD IS NOT NECESSARILY A SAFE PLACE, UNCERTAINTIES ABOUND, AND FEELINGS OF AGENCY ARE OFTEN ILLUSORY. WE CONSIDER HOW INDIVIDUALS ACQUIRE RESILIENCE IN THE AFTERMATH OF TRAUMATIC AND CHRONIC STRESSORS. IN THIS RESPECT, WE REVIEW CHARACTERISTICS OF STRESSORS THAT MAY TRIGGER PARTICULAR BIOLOGICAL AND BEHAVIORAL COPING RESPONSES, AS WELL AS FACTORS THAT UNDERMINE THEIR EFFICACY. TO THIS END, WE EXPLORE STRESSOR DYNAMICS AND SOCIAL PROCESSES THAT FOSTER RESILIENCE IN RESPONSE TO SPECIFIC TRAUMATIC, CHRONIC, AND UNCONTROLLABLE STRESSOR CONTEXTS (INTIMATE PARTNER ABUSE; REFUGEE MIGRATION; COLLECTIVE HISTORICAL TRAUMA). WE POINT TO RESILIENCE FACTORS THAT MAY COMPRISE NEUROBIOLOGICAL CHANGES, SUCH AS THOSE RELATED TO VARIOUS STRESSOR-PROVOKED HORMONES, NEUROTROPHINS, INFLAMMATORY IMMUNE, MICROBIAL, AND EPIGENETIC PROCESSES. THESE BEHAVIORAL AND BIOLOGICAL STRESS RESPONSES MAY INFLUENCE, AND BE INFLUENCED BY, FEELINGS OF SAFETY THAT COME ABOUT THROUGH RELATIONSHIPS WITH OTHERS, SPIRITUAL AND PLACE-BASED CONNECTIONS. 2020