Cortisol Area Under The Curve Research Articles

18 Influence of Pregnant Cattle Grazing Endophyte-Infected Tall Fescue on Innate Immune Response of Male Offspring

Abstract The objective was to evaluate the influence of dams grazing endophyte-infected tall, toxic, fescue (E+) during gestation on innate immune response of male offspring to an endotoxin challenge. Crossbred pregnant multiparous cows (n = 36) bred to Red Angus sires were housed in replicated E+ or novel endophyte-infected, non-toxic, fescue (NE+) pastures before breeding and through the length of gestation. After parturition, cows and calves were moved to a common bermudagrass pasture until calves were weaned. From this calf-crop, a subset of post-weaned steers (E+ n = 8; NE+ n = 8) were selected for a lipopolysaccharide (LPS) challenge. Steers (302 ± 36 d of age; 261 ± 62 kg body weight) were fitted with jugular vein catheters >7 h before sampling. Blood was collected every 30 min starting 2 h before (Pre-LPS) and 9 h following (Post-LPS) LPS administration (0.5 µg/kg body weight). Sickness behavior score (SBS), cortisol, and glucose were analyzed every 30 min. Complete blood count (CBC) and rectal temperature (RT) were analyzed hourly. Peak concentration, time at peak concentration, baseline, return to baseline, and area under the curve (AUC) were evaluated for cortisol and glucose. Cortisol and glucose were determined by radioimmunoassay and hexokinase colorimetric assay, respectively. The CBC data were analyzed using a Hemavet hemocytology analyzer. Pre-LPS and Post-LPS cortisol, glucose, SBS, RT, and CBC were analyzed using the MIXED procedure of SAS specific for repeated measures with treatment, time, and the interaction as fixed effects and dam sire breed as a random effect. Peak concentration, time at peak concentration, baseline, return to baseline, and AUC for cortisol and glucose were analyzed using the MIXED procedure of SAS with treatment as a fixed effect and dam sire breed as a random effect. There was a Pre-LPS treatment by time interaction for RT (P < 0.05). Pre-LPS monocyte count was lower in offspring of dams grazing E+ relative to NE+ during gestation (P < 0.05). Pre-LPS hematocrit was increased in offspring of dams grazing E+ relative to NE+ during gestation (P < 0.05). There was a Pre-LPS effect of time on SBS (P < 0.05). As expected, Post-LPS cortisol, glucose, RT, WBC, neutrophil count, lymphocyte count, lymphocyte percentage, eosinophils count, eosinophils percentage, hematocrit percentage, RBC, and platelets changed over time in response to LPS (P < 0.05). Post-LPS lymphocyte count and monocyte percentage were decreased in offspring of dams grazing E+ relative to NE+ during gestation (P < 0.05). Post-LPS eosinophils count, eosinophil percentage, and hematocrit were increased in offspring of dams grazing E+ relative to NE+ during gestation (P < 0.05). There was a Post-LPS treatment by time interaction for monocyte count and neutrophil percentage (P < 0.05). Preliminary results suggest an altered innate immune response of male offspring of dams grazing toxic relative to novel fescue during gestation.

Food-induced cortisol secretion is comparable in lean and obese male subjects.

Hypercortisolism is a risk factor for obesity. Cortisol increases in response to food intake in lean subjects. In obese subjects, disturbances of the food-induced cortisol peak were reported, but data from sufficiently powered and well-controlled trials are lacking. Understanding the cortisol response to food is essential as amplified or recurrent cortisol surges could lead to hypercortisolism and contribute to obesity. Therefore, we investigate the cortisol response to food in lean and obese subjects. This is a non-randomized, open-label study. We assessed serum cortisol values after a high-calorie meal in lean and obese male subjects. Cortisol levels were frequently assessed before and for 3 h after food intake. A total of 36 subjects (18 lean and 18 obese) were included. There was no difference in overall cortisol levels between both groups during the study (area under the curve (AUC) obese: 55,409 ± 16,994, lean: 60,334 ± 18,001, P = 0.4). Total cortisol levels reached peak concentrations 20 min after food intake in both groups; the maximum cortisol increase was similar in both groups (cortisol increase obese: 69.6 ± 135.5 nmol/L, lean: 134.7 ± 99.7 nmol/L; P = 0.1). There was no correlation between body mass index and baseline cortisol values (R2 = 0.001, P = 0.83), cortisol increase (R2 = 0.05, P = 0.17), or cortisol AUC (R2 = 0.03, P = 0.28). This study demonstrates that high-calorie food intake causes an immediate and substantial cortisol response in lean and obese subjects and is independent of body weight. This study demonstrates that high-calorie food intake causes an immediate and substantial cortisol response in lean and obese subjects, independent of body weight. In contrast to the current literature, our findings show that the physiological cortisol response to food is intact in obesity. The substantial and prolonged increase further supports the hypothesis that frequent high-calorie meals cause hypercortisolism and aggravate weight gain.

The impact of a stress management intervention including cultural components on stress biomarker levels and mental health indicators among indigenous women

We examined the effectiveness of a 26-week culture-inclusive intervention on reducing salivary stress biomarker levels, and perceived stress, depressive, and post-traumatic stress disorder (PTSD) symptoms measured using scales in 53 Indigenous women in Ontario, Canada. Statistical analyses compared the average biomarker levels, and the area under the curve (AUC) of biomarkers. Differences in biomarkers and mental health scale scores pre- and post-intervention were compared using mixed models with a random intercept. Interaction terms were included between the intervention and age, education, disability, and HIV status, individually, to test for sub-group differences. Cortisol AUC post-intervention was decreased compared to pre-intervention (β -1.29 µg/dL; 95%CI -2.35, -0.23). There was a slight decrease in perceived stress levels (aOR: -2.80; 95%CI -5.09, -0.50). The associations were stronger among women of younger age, higher education, and no disabilities. These interventions can be effective, but future interventions should target Indigenous population sub-groups to address individual needs.

Prediabetes and mild hepatosteatosis are associated with blunted cortisol response to glucagon but not to growth hormone

BackgroundAlthough there is a close relationship between cortisol and growth hormone (GH) levels, glucose intolerance and hepatosteatosis, changes in GH and the hypothalamo-pituitary-adrenal (HPA) axis were not previously studied in prediabetes. The main purpose of the present study was to assess changes in GH and HPA axis and their relationship with hepatosteatosis in prediabetic patients. MethodsForty prediabetic patients, with body-mass index (BMI) 25–35kg/m2, and 23 healthy individuals, with normal glucose tolerance and similar age and BMI, were included. The 75g oral glucose tolerance test and glucagon stimulation test (GST) were used. ResultsNo significant differences were detected between prediabetic patients and healthy individuals in terms of insulin-like growth factor-1 (IGF-1), insulin-like growth factor-binding protein-3 (IGFBP-3), IGF-1/IGFBP3 ratio or adrenocorticotropic hormone (ACTH). GH responses to GST did not differ between groups. On the other hand, peak cortisol and area under the curve (AUC) (cortisol) response on GST were significantly lower in prediabetic patients. Both peak GH and AUC (GH) response on GST correlated negatively with waist circumference and body weight. The degree of hepatosteatosis correlated negatively with peak cortisol, GH, AUC (cortisol) and AUC (GH) response on GST. ConclusionCortisol response to GST is decreased in prediabetic patients, with relatively well conserved GH response. This suggests altered HPA axis responsiveness in prediabetes, as is known in diabetes. Thus, HPA axis changes in patients with diabetes probably start before the development of diabetes as such.

Mild to Moderate Sleep Restriction Does Not Affect the Cortisol Awakening Response in Healthy Adult Males.

The cortisol awakening response (CAR) is a distinct rise in cortisol that occurs upon awakening that is thought to contribute to arousal, energy boosting, and anticipation. There is some evidence to suggest that inadequate sleep may alter the CAR, but the relationship between sleep duration and CAR has not been systematically examined. Healthy males (n = 111; age: 23.0 ± 3.6 yrs) spent 10 consecutive days/nights in a sleep laboratory. After a baseline night (9 h time in bed), participants spent either 5 h (n = 19), 6 h (n = 23), 7 h (n = 16), 8 h (n = 27), or 9 h (n = 26) in bed for seven nights, followed by a 9 h recovery sleep. The saliva samples for cortisol assay were collected at 08:00 h, 08:30 h and 08:45 h at baseline, on experimental days 2 and 5 and on the recovery day. The primary dependent variables were the cortisol concentration at awakening (08:00 h) and the cortisol area under the curve (AUC). There was no effect of time in bed on either the cortisol concentration at awakening or cortisol AUC. In all the time in bed conditions, the cortisol AUC tended to be higher at baseline and lower on experimental day 5. Five consecutive nights of mild to moderate sleep restriction does not appear to affect the CAR in healthy male adults.

Relationship between psychological stress and ghrelin concentrations in pregnant women with overweight or obesity

Exposure to, perception of, and response to stress have all been shown to influence appetite and dietary behaviors in non-pregnancy human and animal studies, mediated in part by the appetite stimulating hormone ghrelin. Yet, the impact of prenatal stress on biological pathways associated with appetite in the context of pregnancy is not well understood. The objective of this study was to assess the relationship between these layered dimensions of stress with fasting and postprandial plasma ghrelin concentrations among Hispanic pregnant women with overweight or obesity, a population known to experience heightened levels of stress. Thirty-three non-diabetic Hispanic women with pre-pregnancy body mass index of 25.0–34.9 kg/m2 participated in a crossover study at 28–32 weeks’ gestation. At each visit, participants provided fasting blood and saliva samples, consumed a standardized mixed-meal, and completed a 15-minute task: friendly conversation (control) or the Trier Social Stress Test (experimental stress exposure). Six timed blood and saliva samples were collected up to 2 h from baseline and assayed for ghrelin and cortisol, respectively, and area-under-the-curve (AUC) values were computed. Day-to-day stress levels were assessed by the Perceived Stress Scale. Physiological and psychological stress reactivity was determined by cortisol AUC and change in self-reported affect state, respectively, during the experimental stress visit. Maternal perceived stress was positively associated with ghrelin concentrations in the fasted (β = 0.06, p = 0.02) and postprandial state (β = 0.05, p = 0.02). Mean ghrelin AUC was not significantly different following acute stress versus control. Measures of acute stress reactivity were not associated with ghrelin AUC. Contrary to our hypothesis, among Hispanic pregnant women with overweight and obesity, exposure to an acute stress induction task did not alter postprandial ghrelin concentrations, and changes in individual psychological and physiological stress reactivity did not associate with postprandial ghrelin. However, our findings suggest that maternal report of general perceived stress over the last month is associated with higher fasting and postprandial ghrelin concentrations. Differences in the effects of short-term stress exposure versus day-to-day perception of stress on appetite and food intake in pregnancy deserves further investigation.

Maternal Chronic Perceived Stress, but Not Acute Stress Exposure, Is Associated With Ghrelin Levels Among Hispanic Pregnant Women With Overweight or Obesity

ObjectivesThe aim of this study is to test the effects of maternal chronic and acute psychological stress on plasma ghrelin levels among pregnant women with overweight or obesity.MethodsN = 33 Hispanic women without diabetes and a pre-pregnancy BMI of 25.0–34.9 Kg/m2 participated in a crossover study at 28–32 weeks’ gestation. Perceived stress levels over the past month were assessed by the Perceived Stress Scale. Women attended the lab in the fasted state on two separate days and consumed a breakfast shake immediately after a fasting blood and saliva sample collection on each visit, followed by a 15 minute task: friendly conversation (control) on visit 1 or the standardized Trier Social Stress Test on visit 2 to elicit acute stress. Six postprandial blood and saliva samples were collected at intervals up to 2 hours post-prandial and assayed for ghrelin and cortisol, respectively. The area-under-the-curve (AUC) for ghrelin and cortisol were computed. Differences in ghrelin AUC between visits were compared by paired t-tests and repeated measures ANOVA adjusting for gestational age at visit 2. Associations between perceived stress scores with fasting and ghrelin AUC, and between cortisol AUC and ghrelin AUC following acute stress exposure were analyzed by linear regression, adjusting for gestational age.ResultsPerceived stress score was positively associated with ghrelin levels both in the fasted (beta = 0.06, p = 0.02, 95% CI = 0.01, 0.12) and postprandial state (beta = 0.05, p = 0.02, 95% CI = 0.01, 0.09), which remained significant after adjusting for gestational age. Mean ghrelin AUC following a meal was lower after acute stress compared to the control condition (10.19 ± 0.37 vs 10.24 ± 0.40, p = 0.03), but this difference was not significant after adjusting for gestational age (p = 0.59). Salivary cortisol reactivity to acute stress was also not associated with ghrelin AUC (beta = −0.02, p = 0.92, 95% CI = −0.38, 0.35).ConclusionsChronic perceived stress in pregnant women with overweight and obesity may contribute to higher ghrelin levels both in the fasted state and after consuming a meal. Postprandial ghrelin is not affected by acute stress exposure in this population of women in the third trimester of pregnancy.Funding SourcesNational Institute of Child Health and Human Development.

0379 At-home Sample Collection for Identification of Alterations in HPA-axis Activity and Cortisol Area Under the Curve

Abstract Introduction Sleep problems are associated with alterations in diurnal cortisol patterns, reflective of altered hypothalamic-pituitary-axis (HPA) activity. At-home collection of dried samples for measurement of urinary free cortisol are useful for assessment of diurnal rhythms because they do not impose the stress or sleep disruption associated with inpatient studies. The purpose of this analysis was to assess urinary cortisol responses among a large real-world dataset of at-home collection kit users and the potential for utility in identifying alterations in HPA-axis activity. Methods This retrospective analysis evaluated data from 3,966 individuals who used a Sleep and Stress Test (Everlywell, Inc.) between September 2017 and July 2021. Four dried urine spot samples were collected according to habitual sleep patterns: upon waking (T1), two hours after waking (T2), prior to the evening meal (T3), and at bedtime (T4). Urinary free cortisol normalized to creatinine, indicative of HPA-axis activity was assessed (area under the curve (AUC), wake to bedtime diurnal cortisol slope (DCS), mid-morning (T2) and bedtime (T4) cortisol levels). Sample reference ranges were established from two standard deviations above and below the log-transformed mean at each time point, values were reverted to original units for reporting. Results The sample was predominantly female (n=2,832, 71%). Mean age was 42.8 (sd=12.0) years. Seventy-eight individuals had mid-morning (T2) cortisol levels that were higher than the sample reference range (7.0-170.7 ug/g Cr), and 88 individuals below. Bedtime (T4) cortisol levels were elevated in 145 individuals (reference range 1.1-25.0 ug/g Cr). Total AUC for cortisol was high in 93 and low in 81 of individuals. The slope of the diurnal cortisol response was flattened in 20.6% (n=816) of the sample. Conclusion This real-world study demonstrates that at-home dried urine sample collection can be used to characterize normal and atypical HPA-axis activity. Convenient assessment of alterations in diurnal cortisol patterns are critical in identifying and understanding the mechanisms of HPA-axis activity common in sleep disruptions/disorders. Future studies utilizing this methodology may prove useful in identifying subpopulations with altered HPA-axis activity, sleep issues, and potential relationships to cardiometabolic health. Support (If Any)

Meditative practices, stress and sleep among students studying complementary and integrative health: a cross-sectional analysis.

BackgroundThe International Cohort on Lifestyle Determinants of Health (INCLD Health) is an ongoing, prospective cohort study assessing the health behaviours and lifestyles of higher education students, including their use of specialty diets and complementary and integrative health (CIH) practices. Purpose: This cross-sectional analysis of the INCLD Health cohort aims to (1) evaluate the associations between perceived stress, sleep disturbance, and meditative practices with diurnal salivary free cortisol and (2) evaluate the associations of meditative practices as well as mind-body practices with perceived stress and sleep disturbance.MethodsSerial multivariable linear regression models, adjusting for sociodemographic and lifestyle behaviours, were used to assess associations of (1) perceived stress, sleep disturbance, and meditative practices with salivary cortisol, and (2) meditative practices as well as mind-body practices with perceived stress and sleep disturbance. Meditative and mind-body practices were evaluated using a stress-management and self-care survey; perceived stress and sleep disturbance were evaluated using the 10-item Perceived Stress Scale (PSS), and the patient reported outcome measures information system-29 (PROMIS-29) sleep sub-score respectively. Salivary cortisol was collected at 4 time points over a 24-hour period and area under the curve (AUC) calculations conducted.Results82.5% (n = 80) of participants utilized at least monthly meditative practices. Greater disturbed sleep, but not perceived-stress, meditative, nor mind-body practices was independently associated with increased AUC cortisol (b = 0.02, 95% CI: 0.002–0.05, p = 0.03) after adjusting for age, sex, race, ethnicity, and BMI. Neither meditative nor mind-body practices were associated with perceived stress or disturbed sleep.ConclusionsAmong INCLD Health participants, greater sleep disturbance, but not perceived stress or meditative practices were associated with daytime cortisol.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12906-022-03582-5.

The stimulatory effects of glucagon on cortisol and GH secretion occur independently from FGF-21.

Glucagon stimulation test (GST) is used to assess the hypothalamo-pituitary-adrenal (HPA) and growth hormone (GH) axes with an incompletely defined mechanism. We aimed to assess if glucagon acted through fibroblast growth factor-21 (FGF-21) to stimulate cortisol and GH secretion. The secondary outcome was to determine the relationship of FGF-21 with variable GH responses to GST in obesity. A total of 26 healthy participants; 11 obese (body mass index (BMI) > 30 kg/m2) and 15 leans (BMI < 25 kg/m2) were included. Basal pituitary and target hormone levels were measured and GST was performed. During GST, glucose, insulin, cortisol, GH, and FGF-21 responses were measured. The mean age of the participants was 26.3±3.6 years. Glucagon resulted in significant increases in FGF-21, glucose, insulin, cortisol, and GH levels. The levels of basal cortisol, GH, FGF-21, and IGF-1 were similar in the two groups. The peak GH and area under the curve (AUC)(GH) responses to GST in the obese group were lower than those of the normal-weight group with a different pattern of response. There were no differences between the groups in terms of peak cortisol, AUC(cortisol), peak insulin, AUC(insulin), peak FGF-21, and AUC(FGF21). Obesity was associated with significantly increased glucose and insulin responses and slightly decreased FGF-21 response to glucagon. Obesity was associated with blunted and delayed GH, but preserved cortisol responses to GST. This is the first study showing that glucagon stimulates the HPA and GH axis independently from FGF-21. The delayed GH response to GST in obesity does not seem to be related to FGF-21.

The stimulatory effects of glucagon on cortisol and GH secretion occur independently from FGF-21

Glucagon stimulation test (GST) is used to assess the hypothalamo-pituitary-adrenal (HPA) and growth hormone (GH) axes with an incompletely defined mechanism. We aimed to assess if glucagon acted through fibroblast growth factor-21 (FGF-21) to stimulate cortisol and GH secretion. The secondary outcome was to determine the relationship of FGF-21 with variable GH responses to GST in obesity. A total of 26 healthy participants; 11 obese (body mass index (BMI) > 30 kg/m2) and 15 leans (BMI < 25 kg/m2) were included. Basal pituitary and target hormone levels were measured and GST was performed. During GST, glucose, insulin, cortisol, GH, and FGF-21 responses were measured. The mean age of the participants was 26.3±3.6 years. Glucagon resulted in significant increases in FGF-21, glucose, insulin, cortisol, and GH levels. The levels of basal cortisol, GH, FGF-21, and IGF-1 were similar in the two groups. The peak GH and area under the curve (AUC)(GH) responses to GST in the obese group were lower than those of the normal-weight group with a different pattern of response. There were no differences between the groups in terms of peak cortisol, AUC(cortisol), peak insulin, AUC(insulin), peak FGF-21, and AUC(FGF21). Obesity was associated with significantly increased glucose and insulin responses and slightly decreased FGF-21 response to glucagon. Obesity was associated with blunted and delayed GH, but preserved cortisol responses to GST. This is the first study showing that glucagon stimulates the HPA and GH axis independently from FGF-21. The delayed GH response to GST in obesity does not seem to be related to FGF-21.

Curvilinear associations between family income in early childhood and the cortisol awakening response in adolescence

Previous evidence on cortisol output and socioeconomic status (SES) has been mixed, with studies finding that lower SES can be associated with higher or lower cortisol output, and null associations have also been reported. We hypothesized that these inconsistencies may be due to an underlying curvilinear, inverted-U pattern of association, such that low income is related to increased likelihood of both low and high cortisol output. We tested these curvilinear links among family income and cortisol indices in the Avon Longitudinal Study of Parents and Children (N = 803). Maternal reports of family income when the study children were 33 and 47 months of age were averaged to estimate early-childhood family income. Three cortisol indices were derived from samples collected in adolescence (15.5 years of age): the cortisol awakening response (CAR), area under the curve (AUC) cortisol, and the diurnal cortisol slope. As hypothesized, the CAR exhibited a curvilinear, inverted-U relation with childhood income, with low childhood income being associated with both the lowest and the highest CARs. These findings suggest that discrepancies in prior findings on low SES and the CAR may be due to curvilinear patterns of association. However, childhood income was not significantly associated with adolescent cortisol diurnal slope or AUC. Future work should clarify the factors that might predispose to high versus low CAR given equivalent low SES in childhood.

Cortisol Responses to a Laboratory Challenge: The Moderating Role of Cognitive Performance

Recent theoretical and empirical studies have considered higher cognitive performance as a protective factor with respect to reactivity, recovery and habituation to acute stressors. The goal of our study was to examine the individual role of inhibition, working memory, processing speed, reasoning, and category fluency in the regulation of the cortisol response to a laboratory challenge. Younger, middle-aged, and older participants (N =109, aged 22-84, M=55.90, SD=16.35) were invited to a laboratory session comprising a driving simulation and a set of cognitive tasks. At least one week in advance, baseline cognitive performance was measured using the Brief Test of Adult Cognition by Telephone (BTACT). Throughout the lab session, five saliva samples were taken, which allowed for the computation of a global measure of cortisol release (area under the curve (AUC)). Cortisol AUC was regressed on the individual BTACT cognitive tests, while controlling for age, sex, education, body mass index, physical activity, and time since awakening. The results revealed that inhibition and working memory significantly accounted for the cortisol response. These associations remained significant when other factors such as smoking, caffeine consumption, and medication use were included as covariates. The contributions of reasoning and speed of processing approached significance. Our findings contribute to the emerging evidence that cognitive functioning modulates stress responses to acute stressors. The findings are discussed in the context of cognitive interventions with transfers and implications for stress processes and healthy aging.

Effects of Mindfulness-Based Stress Reduction on Experimental Pain Sensitivity and Cortisol Responses in Women With Early Life Abuse: A Randomized Controlled Trial.

Early life abuse (ELAb) initiates pathophysiological cascades resulting in long-term maladaptive stress responsivity, hyperalgesia, and an increased risk of psychopathology. Mindfulness-based stress reduction (MBSR) is effective in modifying psychological and somatic symptoms; thus, we predicted that MBSR would be particularly efficacious for women with ELAb. Medically healthy women (mean age = 31 years) with or without a history of early (≤13 years) physical or sexual abuse provided self-report measures and were tested in the laboratory before and after randomization to standard MBSR (n = 52) or social support (SSG) (n = 60) for 8 weeks. The laboratory procedure involved pain testing using the cold pressor and temporal summation of heat pain (indexing central sensitization) procedures, and exposure to the Trier Social Stress Test. Plasma cortisol in response to the experimental protocol was assessed as area under the curve (AUC). The interventions differentially impacted pain sensitivity and cortisol AUC for women with ELAb, as MBSR increased the temporal summation of heat pain intensity ratings (p = .024) and reduced cortisol AUC (p = .004). For women without ELAb, MBSR decreased cold pressor tolerance (p = .045) and decreased the temporal summation of heat pain intensity ratings relative to SSG (p = .024). Both MBSR and SSG improved depression symptoms and emotion regulation abilities (p values < .001); however, MBSR was associated with greater benefits in describing emotions (p = .008) and impulse control (p = .017) for women with ELAb. Women with ELAb benefited from MBSR-specific improvements in central sensitization, mindfulness skills, and emotion regulation abilities. This is the first study to examine the efficacy of MBSR in modifying affective and somatic symptoms based on ELAb status and provides evidence for considering ELAb in tailoring treatment approaches.Trial Registration: ClinicalTrials.gov Identifier: NCT01995916; https://clinicaltrials.gov/ct2/show/NCT01995916.

Behavioral and cortisol responses to feeding frequency in pregnant sows under isocaloric intake.

The study focused on behavioral and cortisol responses to feeding frequency in pregnant sows under isocaloric intake. Twenty-four sows [(Landrace × Yorkshire); BW 216.70 ± 3.98 kg; parity 3.04 ± 0.53] were balanced for parity and randomly assigned to 1 of 3 feeding frequency regimes. Sows were fed corn–soybean meal-based diet 1× [0730 (Control), T1], 2× [half ration at 0730 and 1530 hours, T2], or 3× [one-third portion at 0730, 1130, and 1530 hours, T3] from days 30 to 60 of gestation. Sows received 7055 kcal ME/d during gestation from 2.21 kg of diet formulated to contain SID Lys/ME of 1.71 g/Mcal. Saliva samples were collected every 2 hr from 0630 to 1830 hours on day 52 and assayed for cortisol using ELISA procedure. Behavior data were collected for 7 d from day 53 of gestation by affixing a remote insights ear tag to each sow. Each sow had 120,960 data points categorized into: “Active”, “Feed,” or “Dormant”. Because of housing constraint, all sows were housed in individual stalls in the same room presenting a potential limitation of the study. The data were analyzed using PROC MIXED and GLIMMIX procedures of SAS 9.4 for cortisol and behavior count data, respectively. Sow was the experimental unit. The area under the curve (AUC) is quantitative evaluation of response as threshold varies over all possible values. The T2 sows had reduced 12-hr cortisol AUC compared with control sows (P = 0.024) and T3 sows (P = 0.004), respectively. The T2 sows had lower 3 hr (P = 0.039) and 5 hr (P = 0.015) postfeeding cortisol AUC compared with control sows. Feed anticipatory activity (FAA), 24-hr total activity, and feeding activities (eating and/or sham chewing) were reduced for T2 sows relative to the control and T3 sows (P < 0.01). Consequently, T2 sows had lower 24-hr total activity (P < 0.001) and feeding activities (P < 0.001) AUC compared with both the control and T3 sows, respectively. The T3 sows had greater FAA (P < 0.001) and 24-hr total activity AUC (P = 0.010) compared with control sows. Our data although inconclusive due to small sample size, twice daily feeding appears to be the threshold that reduces sows’ total activity AUC, feeding activity AUC, and activation of hypothalamic–pituitary–adrenal axis, reduced hunger, and exhibit potential to improve sow welfare in relation to once and thrice daily feeding regimes under isocaloric intake per kilogram live metabolic weight.

Stress-Induced Suppression of Food Intake in Overweight and Obese Adolescents.

Overweight adolescents exhibit greater cortisol reactivity in response to acute stress and are more likely to eat in response to emotional cues, which suggest an increased susceptibility to stress-induced eating. The purpose of this study was to examine the biological (cortisol and α-amylase reactivity) and behavioral (caloric intake) responses to an acute stressor in overweight adolescents. Fifty-one adolescents ages 14 to 19 years (47% female, 55% white; body mass index, 31.2 ± 0.8 kg/m) were exposed to the Trier Social Stress Test and a control condition on separate days. Immediately after each condition, participants were provided with snacks to eat at their leisure. Reactivity was assessed via salivary cortisol and α-amylase area under the curve (AUC), and adolescents were categorized as high or low reactors. Cortisol AUC was higher during the stress condition (19.6 ± 0.2 μg/dl · min) compared with the control condition (11.4 ± 0.9 μg/dl · min, p < .001). α-Amylase AUC was not different during the stress condition (9999 ± 987 U/ml · min) compared with the control condition (8762 ± 865 U/ml · min, p = .145). Overall, adolescents consumed fewer calories during the stress condition (488 ± 51 kcal) compared with the control condition (637 ± 42 kcal, p = .007). High cortisol reactors decreased their calorie consumption from the control condition (716 ± 52 kcal) to the stress condition (457 ± 53 kcal, p = .001), whereas low cortisol reactors did not change their consumption (stress: 518 ± 87 kcal versus control: 561 ± 62 kcal, p = .574). High cortisol reactivity in overweight adolescents resulted in decreased calorie consumption after an acute stressor. Further research is needed to understand the mechanisms underlying stress-induced suppression of food intake in overweight adolescents.

9 Behavioral and stress responses to feeding frequency in pregnant sows under isocaloric conditions

Abstract The objective of this study was to investigate behavioral and stress responses to feeding frequency in pregnant sows under isocaloric conditions. Eighteen sows (Landrace × Yorkshire); BW 226.10 ± 1.29 kg; parity 3.1 ± 0.42); were blocked by parity and randomly assigned to 1 of 3 feeding frequency regimes. Sows were fed corn-soybean meal-based diet 1× [0730 (Control, T1), 2× “[half ration at 0730 and 1530 h (T2)]” and then “[one-third portion at 0730, 1130, and 1530 h (T3)]”. On average, sows received 7190 kcal ME d−1 during gestation from 2.25 kg of diet formulated to contain SID Lys/ME of 1.71 g/Mcal. Saliva samples were collected from 0630 to 1830 h, 2 hrs apart and assayed for cortisol using ELISA technique. Behavior data were collected for 7 d from d 53 of gestation by affixing a Remote Insights ear tag to each sow. Each sow had 120,960 data points categorized into: “Active,” “Feed” or “Dormant”. The data were analyzed using GLIMMIX procedure of SAS 9.4 with treatment as fixed effect and sow as random effect. Results were considered statistically significant when P &lt; 0·05 and were considered as trends when P ≤ 0·10. Sow was the experimental unit. A 24 h area under the curve (AUC) was calculated by trapezoidal method. The P-values were adjusted for multiplicity based on Tukey Kramer’s method. A 24 h total activity and total feeding activity AUC were reduced in sows fed 2× daily compared with sows fed 1× and 3× daily (P &lt; 0.01). A 12 h cortisol AUC was lower for sows fed 2× daily relative to treatment groups fed 1× and 3× daily (P &lt; 0.02). In conclusion, feeding pregnant sows twice daily may improve sow welfare by reducing feeding activity, total activity, and the activation of hypothalamic-pituitary-adrenal (HPA) axis.

5 Effect of feeding time on behavioral and stress responses in gestation sows under isocaloric conditions

Abstract Investigated the effect of feeding time on behavior and stress responses in pregnant sows under isocaloric conditions. Eighteen sows (Landrace × Yorkshire); BW 248.6 ± 2.8 kg; parity 3.30 ± 0.39); were blocked by parity and randomly assigned to 1 of 3 feeding times. Corn-soybean meal-based diet was fed once at: 0730 (Control, T1), 1130 (T2), and 1530 h (T3). On average, sows received 7190 kcal ME d−1 during gestation from 2.25 kg of diet formulated to contain SID Lys/ME of 1.71 g/Mcal. Saliva samples were collected every 2 h for 12 h in stalls on d 52 of pregnancy and assayed for cortisol using ELISA technique. Behavior data were collected 24 h for 7 d from d 53 of gestation by affixing a Remote Insights ear tag to each sow after 21 d adaptation period. Each sow had 120,960 data points categorized into: “Active,” “Feed” or “Dormant”. Data were analyzed using GLIMMIX procedure of SAS 9.4. Statistical significance was set at P ≤ 0.05, and a trend as 0.05 &lt; P ≤ 0.10. Sow was the experimental unit. A 24 h area under the curve (AUC) was estimated by trapezoidal summation method. Adjustment for multiple comparisons was based on Tukey Kramer’s method. Sows fed daily at 0730 had both lower feeding and total activity compared with sows fed at 1130 h (P &lt; 0.02) but similar to sows fed at 1530 h (P &gt; 0.05). Feeding sows at 1130 h daily resulted in reduced cortisol AUC compared with 1530 h fed sows (P &lt; 0.04) but similar to sows fed at 0730 h (P &gt; 0.05). In conclusion, feeding sows daily at 1130 resulted in increased feed and total activity but reduced cortisol concentration, suggesting that elevated sow activity might not necessary indicate activation of hypothalamic-pituitary-adrenal (HPA) axis.

Early life adversity and depressive symptoms predict cortisol in pregnancy.

Evidence suggests that exposure to early life adversity (ELA) programs the hypothalamic-pituitary-adrenal (HPA) axis to influence responses to later adversity and predisposes women to depression. However, few studies have examined whether ELA moderates the HPA cortisol response to adulthood adversity and depressive symptoms in pregnant women. The aims of this study were to determine (a) whether ELA, adulthood adversity, and depressive symptoms differentially predict patterns of cortisol and (b) whether ELA moderates the relationship of adulthood adversity or depressive symptoms to cortisol. This was a descriptive, cross-sectional study of pregnant women (N = 58, mean = 26.5weeks gestation). Participants completed the Stress and Adversity Inventory and Edinburgh Depression Scale and collected salivary cortisol five times per day for 3days to assess cortisol awakening response (CAR), diurnal cortisol slope, and cortisol area under the curve (AUC). ELA predicted a larger CAR, while depressive symptoms predicted a blunted CAR and higher cortisol AUC. Adulthood adversity predicted a blunted CAR and steeper diurnal slope, but only in women with high ELA. ELA also moderated the effect of depressive symptoms on diurnal slope. Early adversity and depressive symptoms appear to have significant effects on the HPA axis during pregnancy, with early adversity also moderating effects of depressive symptoms and adulthood adversity on cortisol regulation. Early adversity may be an important factor in identifying unique HPA phenotypes and risk for HPA axis dysregulation in pregnancy.

Multiple adrenocortical steroid response to administration of exogenous adrenocorticotropic hormone to hospitalized foals.

BackgroundThe hypothalamic‐pituitary‐adrenal axis regulates the response to sepsis‐associated stress. Relative adrenal insufficiency or adrenocorticotropic hormone (ACTH):cortisol imbalance, defined as a poor cortisol response to administration of ACTH, is common and associated with death in hospitalized foals. However, information on other adrenal steroid response to ACTH stimulation in sick foals is minimal.ObjectiveTo investigate the response of multiple adrenocortical steroids to administration of ACTH in foals.AnimalsHospitalized (n = 34) and healthy (n = 13) foals.MethodsIn this prospective study, hospitalized foals were categorized into 2 groups using cluster analysis based on adrenal steroids response to ACTH stimulation: Cluster 1 (n = 11) and Cluster 2 (n = 23). After baseline blood sample collection, foals received 10 μg of ACTH with additional samples collected at 30 and 90 minutes after ACTH. Steroid and ACTH concentrations were determined by immunoassays. The area under the curve (AUC) and Delta0‐30 were calculated for each hormone.ResultsThe AUC for cortisol, aldosterone, androstenedione, pregnenolone, 17α‐OH‐progesterone, and progesterone were higher in critically ill (Cluster 1) compared to healthy foals (P < .01). Delta0‐30 for cortisol and 17α‐OH‐progesterone was lower in Cluster 1 (24%, 26.7%) and Cluster 2 (16%, 11.2%) compared to healthy foals (125%, 71%), respectively (P < .05). Foals that died had increased AUC for endogenous ACTH (269 versus 76.4 pg/mL/h, P < .05) accompanied by a low AUC for cortisol (5.5 versus 15.5 μg/dL/h, P < .05), suggesting adrenocortical dysfunction.Conclusion and Clinical ImportanceThe 17α‐OH‐progesterone response to administration of ACTH was a good predictor of disease severity and death in hospitalized foals.