SARS-CoV-2 Inactivation on Hard Non-porous Airplane Cabin Material Surfaces was Limited After Exposure to Far UV-C (222 nm) Radiation.

AIMS: To test the efficacy of 222 nm Far UV-C for surface disinfection of SARS-CoV-2 on inanimate surfaces from airplane cabins. METHODS AND RESULTS: Two far ultraviolet (UV-C) irradiation light systems were evaluated for disinfection of SARS-CoV-2. Materials used for carriers (test surfaces) included polished stainless steel and used airplane materials including seatbelt latches, window dust covers, sidewall laminates, and tray tables. CONCLUSIONS: While demonstrating reasonable efficacy under some experimental conditions, the data indicated that 222 nm Far UV-C disinfection alone does not reliably provide a 3 log10 or 99.9% reduction of SARS-CoV-2 on inanimate surfaces from an airplane cabin. An Ushio (Cypress, CA) 1.7" x 2.3" Care222® 12W 222nm BI lamp module tested in triplicate at a low (⁓ 1.5 mJ cm-2), medium (⁓ 3.0 mJ cm-2), and high (⁓ 6 to 9 mJ cm-2) fluence did not provide a ≥ 3 log10 or 99.9% reduction of SARS-CoV-2. The reduction of SARS-CoV-2 was greatest on stainless steel. The result was a log10 reduction of 2.83, 1.33, 2.58, and 2.21 logs for virus samples containing saline, saline with 2.5 mg BSA, saline with 0.25 mg BSA, and artificial saliva respectively at a dosage of 5 to 9 mJ cm-2. The log10 reduction of SARS-CoV-2 in saline with 2.5 mg bovine serum albumin was lowest with 1.33 for stainless steel, 0.93 for belt latch, and 0.61 for tray table at a dosage of 5 to 6 mJ cm-2.The second UV lighting system tested was a prototype mobile wand with a built-in short-pass filtered krypton-chloride cylindrical lamp. One pass of the wand over a tray holding carriers inoculated with SARS-CoV-2 in artificial saliva at a rate of approximately 1 foot (1') per second (sec) exposed the carriers to 7.3 mJ cm-2. The log10 reductions determined for the single pass were 2.97, 3.75, 1.78, 1.91, and 1.28 logs for stainless steel, belt latch, dust cover, sidewall, and tray table respectively. Two passes of the wand generated 17.2 mJ cm-2 and resulted in log10 reductions of 4.04, 3.74, 4.24, 3.68, and 1.66 logs for stainless steel, belt latch, dust cover, sidewall, and tray table respectively. The combination of higher fluence from multiple passes of the wand, the close proximity (10 cm wand to the carrier), the exposure to elevated temperatures up to 35°C, and ozone from the bulb being blown directly onto the carriers contributed to effective viral inactivation on all surfaces except the airplane tray table. The impact of temperature and ozone on viral inactivation should be determined for future testing of the 222 nm UV-C wand.

Social status alters chromatin accessibility and the gene regulatory response to glucocorticoid stimulation in rhesus macaques.

Low social status is an important predictor of disease susceptibility and mortality risk in humans and other social mammals. These effects are thought to stem in part from dysregulation of the glucocorticoid (GC)-mediated stress response. However, the molecular mechanisms that connect low social status and GC dysregulation to downstream health outcomes remain elusive. Here, we used an in vitro GC challenge to investigate the consequences of experimentally manipulated social status (i.e., dominance rank) for immune cell gene regulation in female rhesus macaques, using paired control and GC-treated peripheral blood mononuclear cell samples. We show that social status not only influences immune cell gene expression but also chromatin accessibility at hundreds of regions in the genome. Social status effects on gene expression were less pronounced following GC treatment than under control conditions. In contrast, social status effects on chromatin accessibility were stable across conditions, resulting in an attenuated relationship between social status, chromatin accessibility, and gene expression after GC exposure. Regions that were more accessible in high-status animals and regions that become more accessible following GC treatment were enriched for a highly concordant set of transcription factor binding motifs, including motifs for the GC receptor cofactor AP-1. Together, our findings support the hypothesis that social status alters the dynamics of GC-mediated gene regulation and identify chromatin accessibility as a mechanism involved in social stress-driven GC resistance. More broadly, they emphasize the context-dependent nature of social status effects on gene regulation and implicate epigenetic remodeling of chromatin accessibility as a contributing factor.

Exploring the Preliminary Steps of One County Health Department to Manage the COVID-19 Pandemic.

This case study describes how one county health department in Alabama used the best available evidence to address the needs of its citizens during the first 6 months of the COVID-19 pandemic. The authors explore issues of scope of authority by government officials, individual freedom versus population health, and challenges of health communication during a disease outbreak. Despite the availability of vaccines, boosters, and access to vaccines by children as young as 5 years, COVID-19 cases are on the rise across the United States more than 2 years after the official news broke out of Wuhan, China. Health officials have expressed concerns that backlash against governmental public health during the pandemic will limit public health authorities from responding to the traditional challenges that were present pre-COVID-19 and will remain in a post-COVID-19 world.

Obesogenic diet-associated C-reactive protein predicts reduced central dopamine and corticostriatal functional connectivity in female rhesus monkeys.

Alterations in dopamine (DA) signaling and reductions in functional connectivity (FC; a measure of temporal correlations of activity between different brain regions) within dopaminergic reward pathways are implicated in the etiology of psychopathology and have been associated with increased concentrations of inflammatory markers, including C-reactive protein. Peripheral and central inflammatory cytokines that have been shown to disrupt DA signaling and corticostriatal FC are associated with C-reactive protein, an acute phase reactant that is used translationally as a marker of systemic inflammation. One factor that can significantly increase systemic inflammation to produce neuroadaptations in reward pathways is a diet that results in fat mass accumulation (e.g. obesogenic diet). The current study in female rhesus monkeys maintained in a standard laboratory chow (n = 18) or on obesogenic diet (n = 16) for 12-months tested the hypothesis that an obesogenic diet would alter central DA and homovanillic acid (HVA) concentrations, and be associated with increased CRP concentrations and decreased FC between corticostriatal regions at 12-months following dietary intervention. We specifically assessed FC between the nucleus accumbens (NAcc) and two sub-regions of the prefrontal cortex (PFC) previously associated with CRP concentrations, the ventromedial PFC (vmPFC) and the orbitofrontal cortex (OFC), which are also involved in emotional and motivational salience assessment, and in goal-directed behavior, impulse control and the salience/value of food, respectively. Results showed that CSF DA concentrations were decreased (p = 0.002), HVA:DA ratios were increased (p = 0.016), and body mass index was increased (p = 0.047) over the 12-months of consuming an obesogenic diet. At 12-months, females maintained in the obesogenic diet exhibited higher CRP concentrations than females consuming chow-only (p = 0.008). Linear regression analyses revealed significant CRP by dietary condition interactions on DA concentrations (ß = -5.10; p = 0.017) and HVA:DA ratios (ß = 5.14; p = 0.029). Higher CRP concentrations were associated with lower CSF DA concentrations (r = -0.69; p = 0.004) and greater HVA:DA ratios only in females maintained in the obesogenic dietary condition (r = 0.58; p = 0.024). Resting-state magnetic resonance neuroimaging (rs-fMRI) in a subset of females from each diet condition (n = 8) at 12-months showed that higher CRP concentrations were associated decreased FC between the NAcc and subregions of the prefrontal cortex (PFC; p's < 0.05). Decreased FC between the NAcc and PFC subregions were also associated with lower concentrations of DA and greater HVA:DA ratios (p's < 0.05). Overall, these data suggest that increased inflammatory signaling driving heightened CRP levels may mediate the adverse consequences of obesogenic diets on DA neurochemistry and corticostriatal connectivity.

Methylation of OXT and OXTR genes, central oxytocin, and social behavior in female macaques.

Oxytocin (OXT) and its receptor (OXTR) are encoded by OXT and OXTR, respectively. Variable methylation of these genes has been linked to variability in sociability and neuroendophenotypes. Here we examine whether OXTR or OXT methylation in blood predicts concentrations of OXT in cerebrospinal fluid (CSF) (n = 166) and social behavior (n = 207) in socially-housed female rhesus macaques. We report a similarity between human and rhesus CpG sites for OXT and OXTR and a putative negative association between methylation of two OXTR CpG units with aggressive behavior (both P = 0.003), though this finding does not survive the most stringent correction for multiple comparison testing. We did not detect a statistically significant association between methylation of any CpG sites and CSF OXT concentrations, either. Because none of the tested associations survived statistical corrections, if there is any relationship between blood-derived methylation of these genes and the behavioral and physiological outcomes measured here, the effect size is too small to be detected reliably with this sample size. These results do not support the hypothesis that blood methylation of OXT or OXTR is robustly associated with CSF OXT concentration or social behavior in rhesus. It is possible, though, that methylation of these loci in the brain or in cheek epithelia may be associated with central OXT release and behavior. Finally, we consider the limitations of this exploratory study in the context of statistical power.

Social affiliation predicts mitochondrial DNA copy number in female rhesus macaques.

In many social mammals, social adversity predicts compromised health and reduced fitness. These effects are thought to be driven in part by chronic social stress, but their molecular underpinnings are not well understood. Recent work suggests that chronic stress can affect mitochondrial copy number, heteroplasmy rates and function. Here, we tested the first two possibilities for the first time in non-human primates. We manipulated dominance rank in captive female rhesus macaques ( n = 45), where low rank induces chronic social stress, and measured mitochondrial DNA (mtDNA) copy number and heteroplasmy in five peripheral blood mononuclear cell types from each study subject. We found no effect of dominance rank on either mtDNA copy number or heteroplasmy rates. However, grooming rate, a measure of affiliative social behaviour predicted by high social status, was positively associated with mtDNA copy number in B cells, cytotoxic T cells and monocytes. Our results suggest that social interactions can influence mtDNA regulation in immune cells. Further, they indicate the importance of considering both affiliative and competitive interactions in investigating this relationship.

Social status predicts response to dietary cycling in female rhesus monkeys.

With the prevalence of obesity among women the United States surpassing 40%, it is critical to understand how environmental factors influence appetite, body fat accumulation, and the ability to lose weight and maintain weight loss. Psychosocial stress exposure is a risk factor for increased consumption of calorically dense diets (CDD), which are high in fat and sugars and promote both increased food intake and weight gain. However, it remains unclear how appetite is affected by psychosocial factors when people striving to lose weight restrict intake of unhealthy, calorically dense foods. Using a translational non-human primate model of chronic psychosocial stressor exposure in females (n = 16), mediated by social subordination, we examined ad libitum food intake, weight change, and social behavior during three consecutive, 15-week dietary conditions: 1) obesogenic, dietary choice; 2) chow-only; and 3) a switch back to dietary choice. Data showed that a choice dietary environment that includes both chow and CDD promotes increased calorie consumption of CDD in subordinate female rhesus monkeys during the baseline choice and back-to-choice phases (p = 0.016). Removal of the CDD during the chow-only phase resulted in mild inappetence (p = 0.005) and a loss in body weight (p < 0.001) in subordinate females. Reintroduction of the CDD to subordinate, but not dominant, females was associated with increased calorie intake that surpassed baseline intake (p < 0.001), and greater body weight gain (p = 0.026). There were no effects of diet cycling on total food intake and body weight change in dominant females (p's > 0.05). Overall, our results suggest that adverse psychosocial experience is associated with increased preference for highly palatable, calorically dense food in a choice dietary environment.

Social subordination stress and serotonin transporter polymorphisms: associations with brain white matter tract integrity and behavior in juvenile female macaques.

We examined the relationship between social rank and brain white matter (WM) microstructure, and socioemotional behavior, and its modulation by serotonin (5HT) transporter (5HTT) polymorphisms in prepubertal female macaques. Using diffusion tensor imaging and tract-based spatial statistics, social status differences were found in medial prefrontal cortex (mPFC) WM and cortico-thalamic tracts, with subordinates showing higher WM structural integrity (measured as fractional anisotropy, FA) than dominant animals. 5HTT genotype-related differences were detected in the posterior limb of the internal capsule, where s-variants had higher FA than l/l animals. Status by 5HTT interaction effects were found in (1) external capsule (middle longitudinal fasciculus), (2) parietal WM, and (3) short-range PFC tracts, with opposite effects in dominant and subordinate animals. In most regions showing FA differences, opposite differences were detected in radial diffusivity, but none in axial diffusivity, suggesting that differences in tract integrity likely involve differences in myelin. These findings highlight that differences in social rank are associated with differences in WM structural integrity in juveniles, particularly in tracts connecting prefrontal, sensory processing, motor and association regions, sometimes modulated by 5HTT genotype. Differences in these tracts were associated with increased emotional reactivity in subordinates, particularly with higher submissive and fear behaviors.

Social environment is associated with gene regulatory variation in the rhesus macaque immune system.

Variation in the social environment is a fundamental component of many vertebrate societies. In humans and other primates, adverse social environments often translate into lasting physiological costs. The biological mechanisms associated with these effects are therefore of great interest, both for understanding the evolutionary impacts of social behavior and in the context of human health. However, large gaps remain in our understanding of the mechanisms that mediate these effects at the molecular level. Here we addressed these questions by leveraging the power of an experimental system that consisted of 10 social groups of female macaques, in which each individual's social status (i.e., dominance rank) could be experimentally controlled. Using this paradigm, we show that dominance rank results in a widespread, yet plastic, imprint on gene regulation, such that peripheral blood mononuclear cell gene expression data alone predict social status with 80% accuracy. We investigated the mechanistic basis of these effects using cell type-specific gene expression profiling and glucocorticoid resistance assays, which together contributed to rank effects on gene expression levels for 694 (70%) of the 987 rank-related genes. We also explored the possible contribution of DNA methylation levels to these effects, and identified global associations between dominance rank and methylation profiles that suggest epigenetic flexibility in response to status-related behavioral cues. Together, these results illuminate the importance of the molecular response to social conditions, particularly in the immune system, and demonstrate a key role for gene regulation in linking the social environment to individual physiology.

Understanding the control of ingestive behavior in primates.

This article is part of a Special Issue "Energy Balance". Ingestive behavior in free-ranging populations of nonhuman primates is influenced by resource availability and social group organization and provides valuable insight on the evolution of ecologically adaptive behaviors and physiological systems. As captive populations were established, questions regarding proximate mechanisms that regulate food intake in these animals could be more easily addressed. The availability of these captive populations has led to the use of selected species to understand appetite control or metabolic physiology in humans. Recognizing the difficulty of quantitating food intake in free-ranging groups, the use of captive, singly-housed animals provided a distinct advantage though, at the same time, produced a different social ecology from the animals' natural habitat. However, the recent application of novel technologies to quantitate caloric intake and energy expenditure in free-feeding, socially housed monkeys permits prospective studies that can accurately define how food intake changes in response to any number of interventions in the context of a social environment. This review provides an overview of studies examining food intake using captive nonhuman primates organized into three areas: a) neurochemical regulation of food intake in nonhuman primates; b) whether exposure to specific diets during key developmental periods programs differences in diet preferences or changes the expression of feeding related neuropeptides; and c) how psychosocial factors influence appetite regulation. Because feeding patterns are driven by more than just satiety and orexigenic signals, appreciating how the social context influences pattern of feeding in nonhuman primates may be quite informative for understanding the biological complexity of feeding in humans.

Small changes in meal patterns lead to significant changes in total caloric intake. Effects of diet and social status on food intake in female rhesus monkeys.

Social subordination in macaques is a well-established model to study the adverse effects of psychosocial stress on a number of health outcomes, including stress-induced eating. The present analysis was conducted to empirically define a meal among free-feeding female rhesus monkeys and to examine the roles of meal patterning (e.g., meal size, meal frequency, and snacking patterns) in findings from a previous study demonstrating that psychosocial stress increases overall caloric intake among subordinate animals with access to a highly palatable diet. Results indicate that all animals, regardless of social status, consumed more frequent meals, larger meals, and more calories in the form of snacks when a highly palatable diet was available. Additional findings suggest that subordinate animals consumed significantly larger meals compared to their dominant counterparts regardless of the dietary environment. Additionally, subordinate females with a history of exposure to the palatable diet consumed significantly more snack calories than both dominant and subordinate animals without previous exposure to the palatable diet when these females were returned to a standard laboratory diet. These findings illustrate how small changes in meal patterns can lead to significant increases in total caloric intake, which if prolonged, could promote the emergence of an obese phenotype.

Effects of social rank and pubertal delay on brain structure in female rhesus macaques.

Adverse social experience during childhood and adolescence leads to developmental alterations in emotional and stress regulation and underlying neurocircuits. We examined the consequences of social subordination (low social rank) in juvenile female rhesus monkeys, as an ethologically valid model of chronic social stressor exposure, on brain structural and behavioral development through the pubertal transition. Adolescence is a developmental period of extensive brain remodeling and increased emotional and stress reactivity. Puberty-induced increases in gonadal hormones, particularly estradiol (E2), are likely involved due to its organizational effects on the brain and behavior. Thus, we also examined how experimentally delaying pubertal onset with Lupron (gonadotropin releasing hormone -GnRH- agonist used clinically to delay early puberty) interacted with social rank (dominant vs. subordinate) to affect brain and behavioral outcomes. Using a longitudinal experimental design, structural MRI (sMRI) scans were collected on socially housed juvenile female rhesus monkeys living in indoor-outdoor enclosures prior to the onset of puberty (18-25 months), defined as menarche or the initial occurrence of perineal swelling and coloration, and again at 29-36 months, when all control animals had reached puberty but none of the Lupron-treated had. We examined the effects of both social rank and pubertal delay on overall structural brain volume (i.e. intracranial, grey matter (GM) and white matter (WM) volumes), as well as on cortico-limbic regions involved in emotion and stress regulation: amygdala (AMYG), hippocampus (HC), and prefrontal cortex (PFC). Measures of stress physiology, social behavior, and emotional reactivity were collected to examine functional correlates of the brain structural effects. Apart from expected developmental effects, subordinates had bigger AMYG volumes than dominant animals, most notably in the right hemisphere, but pubertal delay with Lupron-treatment abolished those differences, suggesting a role of gonadal hormones potentiating the brain structural impact of social stress. Subordinates also had elevated baseline cortisol, indicating activation of stress systems. In general, Lupron-treated subjects had smaller AMYG and HC volume than controls, but larger total PFC (driven by bigger GM volumes), and different, region-specific, developmental patterns dependent on age and social rank. These findings highlight a region-specific effect of E2 on structural development during female adolescence, independent of those due to chronological age. Pubertal delay and AMYG volume, in turn, predicted differences in emotional reactivity and social behavior. These findings suggest that exposure to developmental increases in E2 modifies the consequences of adverse social experience on the volume of cortico-limbic regions involved in emotional and stress regulation during maturation. But, even more importantly, they indicate different brain structural effects of chronological age and pubertal developmental stage in females, which are very difficult to disentangle in human studies. These findings have additional relevance for young girls who experience prolonged pubertal delays or for those whose puberty is clinically arrested by pharmacological administration of Lupron.

Social subordination impairs hypothalamic-pituitary-adrenal function in female rhesus monkeys.

Linear dominance hierarchies organize and maintain stability in female rhesus macaque (Macaca mulatta) social groups regardless of group size. As a consequence of their low social status, subordinate females suffer from an array of adverse outcomes including reproductive compromise, impaired immune function, and poor cardiovascular health. However, data that differentiate limbic-hypothalamic-pituitary-adrenal axis (LHPA) parameters between dominant from subordinate female monkeys are inconsistent, bringing into question whether social subordination alters the LHPA axis in female macaques. One difficulty in examining LHPA function in macaques may be the confounding effects of cycling ovarian steroids that are known to modulate LHPA activity. The current study used ovariectomized dominant and subordinate female rhesus monkeys to examine the effect that social subordination has on LHPA function by measuring morning and diurnal serum cortisol levels, dexamethasone (Dex) suppression of cortisol, metabolic clearance of Dex, and ACTH stimulation of adrenal cortisol release and cortisol response following exposure to acute social isolation. Compared to dominant females, subordinate females showed diminished morning peak cortisol secretion, weakened glucocorticoid negative feedback, and decreased adrenal cortisol response to an ACTH challenge as well as a restrained cortisol response following social isolation. However, the metabolism of Dex did not account for differences in Dex suppression between dominant and subordinate females. These results indicate that the ability to mount and limit glucocorticoid release is significantly reduced by psychosocial stress in female rhesus macaques, suggesting a hyporesponsive LHPA phenotype which resembles that observed in several human psychopathologies.

Social status modifies estradiol activation of sociosexual behavior in female rhesus monkeys.

Estrogen (E2) has activational effects on sexual motivation and mitigating effects on anxiety-like behaviors that can be attenuated with chronic exposure to psychosocial stress. Some studies suggest that this attenuation can be overcome by higher doses of E2, while others show that chronic psychosocial stress may alter the mechanisms of E2 function, thus reducing any positive benefit from higher doses of E2. To determine the interaction between psychosocial stress and E2 dose on behavior, we examined the scope of attenuation across a suite of socioemotional behaviors, including reproduction, affiliation, aggression, submission, and anxiety-like behaviors on 36 ovariectomized female rhesus monkeys. Females were exposed to graded psychosocial stress, established by an intrinsic female dominance hierarchy, where subordinate animals receive high amounts of harassment. Our data show that E2 dose-dependently increased sexual motivation and male-affiliation in dominant (e.g. low-stress) females, while subordinate females showed no positive effects of E2, even at higher doses. In addition, contact aggression was attenuated in dominant females, while non-contact aggression was attenuated in both dominant and middle-ranking females. These results suggest that the stress-induced attenuation of E2's activational effects on sexual behavior and affiliation with males may not be overcome with higher doses of E2. Furthermore, the observed behavioral consequences of psychosocial stress and E2 dose may be dependent on the behaviors of all the females in the social-group, and better resolution on these effects depends on isolating treatment to individuals within the group to minimize alterations in social-group interactions.

Sex and social status modify the effects of fluoxetine on socioemotional behaviors in Syrian hamsters and rhesus macaques.

Social subordination increases risk for psychiatric disorders, while dominance increases resilience to these disorders. Fluoxetine, a selective serotonin (5HT) reuptake inhibitor whose actions are mediated in part by the 5HT1A receptor (5HT1AR), has sex- and social status-specific effects on socioemotional behavior and aggressive behavior. However, the impact of social status on these sex-specific effects remains unclear. The current study evaluated the impact of acute fluoxetine treatment and social status on dominance-related behaviors in female and male hamsters, and the impact of chronic fluoxetine treatment on socioemotional behavior and 5HT1AR binding potential (5HT1ARBP) in female rhesus macaques. We hypothesized that sex differences in the effects of fluoxetine on aggression in hamsters would be diminished in dominant and enhanced in subordinate males and that aggression in female hamsters would be enhanced in dominants and diminished in subordinates. In female rhesus macaques, we hypothesized that chronic fluoxetine would alter socioemotional behaviors and site-specific 5HT1ARBP in a status-dependent manner. Male (n = 46) and female (n = 56) hamsters were paired with conspecifics for three days to establish social rank. Hamsters received a single dose of 20 mg/kg fluoxetine or vehicle two-hours prior to a test with a non-aggressive intruder. Female rhesus monkeys (n = 14) housed were administered fluoxetine (2.8 mg/kg/day) or vehicle injections chronically for 14-days, separated by a three-week washout period. On Day 15, positron emission tomography neuroimaging for 5HT1ARBP was conducted. Fluoxetine treatment decreased aggression in subordinate female monkeys and subordinate female hamsters but not in dominant females of either species. Fluoxetine decreased aggression in dominant but not in subordinate male hamsters. Fluoxetine also reduced and increased prefrontal 5HT1ARBP in dominant and subordinate females, respectively. Taken together, these results provide cross-species evidence that social status and sex impact how increased 5HT modulates agonistic behavior.

Estradiol effects on behavior and serum oxytocin are modified by social status and polymorphisms in the serotonin transporter gene in female rhesus monkeys.

Despite the well-documented relation between estradiol (E2) and behavior, exposure to stressors may modify sensitivity to E2. The effects of E2 on behavior are, in part, likely related to their modulation of the serotonin (5HT) and oxytocin systems. The short allele (s-variant) polymorphism found in the promoter region of the SLC6A4 gene that encodes the 5HT transporter (5HTT) modulates responsivity to stressors. The current study used ovariectomized adult female rhesus monkeys to evaluate how exposure to the psychosocial stressor of social subordination and polymorphisms in the gene encoding 5HTT influence the behavioral effects of E2 and immunoreactive serum oxytocin. Dominant females had higher levels of oxytocin than subordinate animals even though E2 increased immunoreactive serum oxytocin in all females. E2 increased affiliative behaviors in all animals, with even more of these prosocial behaviors directed at dominant females. S-variant females, regardless of social status, were more aggressive toward more subordinate cage mates and these behaviors too were increased by E2. Subordinate s-variant females are most often involved in agonistic behavior, less affiliative behavior, and were less responsive to the anxiolytic action of E2. The results show that the short allele of the 5HTT gene synergizes with psychosocial stress exposure to affect the behavioral efficacy of E2 while confirming the actions of E2 for producing generalized behavioral arousal in females. Whether differences in the central action of 5HT and/or oxytocin are responsible for this effect requires further study.

Chronic psychosocial stress and experimental pubertal delay affect socioemotional behavior and amygdala functional connectivity in adolescent female rhesus macaques.

In females, pubertal onset appears to signal the opening of a window of increased vulnerability to the effects of stress on neurobehavioral development. What is the impact of pubertal timing on this process? We assessed the effects of pubertal timing and stress on behavior and amygdala functional connectivity (FC) in adolescent female macaques, whose social hierarchy provides an ethologically valid model of chronic psychosocial stress. Monkeys experienced puberty spontaneously (n = 34) or pubertal delay via Lupron treatment from age 16-33 months (n = 36). We examined the effects of stress (continuous dimension spanning dominant/low-stress to subordinate/high-stress) and experimental pubertal delay (Lupron-treated vs. Control) on socioemotional behavior and FC at 43-46 months, after all animals had begun puberty. Regardless of treatment, subordinate monkeys were more submissive and less affiliative, and exhibited weaker FC between amygdala and dorsolateral prefrontal cortex and stronger FC between amygdala and temporal pole. Regardless of social rank, Lupron-treated monkeys were also more submissive and less affiliative but were less anxious and exhibited less displacement behavior in a "Human Intruder" task than untreated monkeys; they exhibited stronger FC between amygdala and orbitofrontal cortex. No interactions between rank and Lupron treatment were observed. These similar behavioral outcomes may reflect the common factor of delayed puberty - whether this is stress-related (untreated subordinate animals) or pharmacologically-induced (treated animals). In the brain, however, delayed puberty and subordination stress had separable effects, suggesting that the overlapping socioemotional outcomes may be mediated by distinct neuroplastic mechanisms. To gain further insights, additional longitudinal studies are required.

Evaluation of the molecular response of corpora lutea to manganese-amino acid complex supplementation in gilts.

Porcine pregnancy establishment and maintenance are dependent on the formation of functional corpora lutea (CL). Manganese (Mn) is critical for CL function as it is a cofactor for Mn superoxide dismutase and enzymes involved in cholesterol synthesis. Previously, we have shown that luteal Mn content increased and luteal progesterone (P4) concentration decreased in the CL of gilts fed diets supplemented with an Mn-amino acid complex (Availa-Mn; Zinpro Corporation) compared with controls fed Mn sulfate. Importantly, serum P4 increased from 0 (estrus onset) to 12 d post estrus (dpe), as expected, but P4 abundance in circulation was not affected by dietary Mn source (P = 0.15). We hypothesized that a more bioavailable Mn source (which results in increased luteal Mn content) would alter the luteal proteome and abundance of mRNA associated with steroid biogenesis during the mid-luteal phase of the estrous cycle. Postpubertal gilts (n = 32) were assigned to one of the four gestation diets. The control diet (CON) contained 20 ppm of supplemental Mn in the form of Mn sulfate. Three additional diets included 20 (TRT1), 40 (TRT2), or 60 (TRT3) ppm of supplemental Mn in the form of a Mn-amino acid complex instead of Mn sulfate. Dietary treatment began at estrus synchronization (approximately 20 d before estrus) and continued through 12 dpe when gilts were euthanized and tissues were collected. Protein and total RNA extracts from the CL were used for proteomic analysis via label-free liquid chromatography with tandem mass spectrometry to assess global protein abundance and quantitative real-time polymerase chain reaction (qRT-PCR) to assess specific mRNA abundance, respectively. Compared with CON, 188, 382, and 401 proteins were differentially abundant (P < 0.10) in TRT1, TRT2, and TRT3, respectively. Gene Ontology enrichment software revealed that proteins involved in P4 signaling and cholesterol synthesis were downregulated in CL of gilts fed Mn-amino acid complex compared with controls. Quantitative RT-PCR showed that relative transcript abundance of genes encoding steroidogenic enzymes (CYP11A1 and StAR) in CL tissue was decreased in gilts from TRT2 compared with CON (P = 0.02), but TRT1 and TRT3 were not affected (P ≥ 0.30). Collectively, these data support our hypothesis that a more bioavailable dietary Mn source may influence luteal function by altering the abundance of protein and mRNA involved in steroidogenesis.

Impact of manganese amino acid complex on tissue-specific trace mineral distribution and corpus luteum function in gilts.

Functional corpora lutea (CL) are required for pregnancy establishment and gestational maintenance in swine, and CL function is susceptible to environmental influences. Manganese (Mn) could be critical in regulating CL function since it is a component of the antioxidant enzyme Mn superoxide dismutase (MnSOD) as well as enzymes involved in cholesterol and steroid hormone synthesis. We hypothesized that a more bioavailable dietary Mn source would increase Mn content in the CL thereby influencing luteal function during the mid-luteal phase of the estrous cycle. Postpubertal gilts (n = 32) were assigned to one of four gestation diets. The control diet (CON) met or exceeded National Research Council (2012) requirements and was formulated to contain 20 parts per million (ppm) of added Mn in the form of Mn sulfate. Three additional diets included 20 (treatment [TRT]1), 40 (TRT2), or 60 (TRT3) ppm of added Mn from a Mn-amino acid complex (Availa-Mn; Zinpro Corporation) instead of Mn sulfate. Dietary treatment began at estrus synchronization onset and continued through 12 days post estrus (dpe) of the ensuing estrous cycle. Blood samples were collected at estrus onset, which was assigned as 0 dpe, as well as 4, 8, and 12 dpe. Gilts were euthanized and tissues were collected at 12 dpe. Serum progesterone (P4) increased (P < 0.01) from 0 to 12 dpe but was unaffected by dietary treatment (P = 0.15) and there was no effect of the interaction between day and treatment (P = 0.85). Luteal Mn content increased (P ≤ 0.05) by 19%, 21%, and 24% in gilts fed TRT1, TRT2, and TRT3, respectively, compared to CON. Luteal P4 concentrations decreased (P = 0.03) 25%, 26%, and 32% in gilts fed TRT1, TRT2, and TRT3, respectively, compared to CON. Relative to CON gilts, CL calcium content decreased (P = 0.02) by 36%, 24%, and 34% for TRT1, TRT2, and TRT3 gilts, respectively. Collectively, these data support the hypothesis that feeding a more bioavailable Mn source increases Mn accumulation in CL tissue. If and how this influences CL function may be related to altered luteal P4 concentrations.

Social subordination alters estradiol-induced changes in cortico-limbic brain volumes in adult female rhesus monkeys.

Women have a higher risk of developing stress-related disorders compared to men and the experience of a stressful life event is a potent risk-factor. The rodent literature suggests that chronic exposure to stressors as well as 17ß-estradiol (E2) can result in alterations in neuronal structure in corticolimbic brain regions, however the translation of these data to humans is limited by the nature of the stressor experienced and issues of brain homology. To address these limitations, we used a well-validated rhesus monkey model of social subordination to examine effects of E2 treatment on subordinate (high stress) and dominant (low stress) female brain structure, including regional gray matter and white matter volumes using structural magnetic resonance imaging. Our results show that one month of E2 treatment in ovariectomized females, compared to control (no) treatment, decreased frontal cortex gray matter volume regardless of social status. In contrast, in the cingulate cortex, an area associated with stress-induced emotional processing, E2 decreased grey matter volume in subordinates but increased it in dominant females. Together these data suggest that physiologically relevant levels of E2 alter cortical gray matter volumes in females after only one month of treatment and interact with chronic social stress to modulate these effects on brain structure.