Reduction In Cortisol Concentration Research Articles

Thermal comfort of Nelore (Bos indicus) and Canchim (Bos taurus x Bos indicus) bulls kept in an integrated crop-livestock-forestry system in a tropical climate

CONTEXTClimate change presents challenges for livestock productivity and animal health. Thus, management strategies to mitigate the effects of the global temperature increase on livestock production have become progressively relevant. However, the use of integrated crop-livestock-forestry systems to optimize the beef cattle thermal balance has not been examined more deeply. OBJECTIVEThe study aimed to evaluate the microclimate in a non-shaded pasture system (NS) and in an integrated crop-livestock-forestry system (ICLF) and its influence on thermoregulatory and endocrine responses of zebu and composite bulls, during different climatic seasons. METHODSThe experiment was carried out in a tropical region, São Carlos-SP, Brazil (21°57′42″S, 47°50′28″W). Nelore (Bos indicus) and Canchim (5/8 Bos taurus x 3/8 Bos indicus) bulls were equally allocated in a non-shaded system (NS; n = 32) or in an integrated crop-livestock-forestry system (ICLF; n = 32). The animals were monthly evaluated and the data were analyzed using a GLM Model. Means were compared using Tukey test (P < 0.05). RESULTS AND CONCLUSIONSThe ICLF system reduced the air temperature (−0.6 °C; P = 0.0010), the Black Globe Temperature and Humidity Index-BGHI (−3.8; P < 0.0001), and the Radiant Thermal Load (−104 W/m2; P < 0.0001) compared to the NS system. The infrared thermograms of NS bulls were characterized by higher temperatures on the surface of the back and in the trunk, during Autumn and Winter (P < 0.05). In addition, NS bulls presented higher respiratory rate (RR: 35.85 ± 0.88 vs 31.97 ± 0.88 breaths/min; P = 0.0210) and internal body temperature (BT: 39.54 ± 0.05 vs 39.35 ± 0.05 °C; P = 0.0057) during Autumn. There was a significant reduction in cortisol concentration (−12.13 ng/mL; P < 0.05) in both systems throughout the experiment. Nelore bulls had lower RR and BT, lower mean concentration of cortisol, and higher secretion of triiodothyronine than Canchim bulls. The ICLF system was effective in mitigating the microclimate of pastures due to the action of natural shading, providing greater thermal comfort, especially for composite animals, and favored the maintenance of homeothermy in the bulls. SIGNIFICANCEThis thesis has provided a deeper insight into the physiological mechanisms involved in the thermoregulation of cattle raised in integrated crop-livestock-forestry systems. The insights gained from this study may be of assistance to indicate ICLF as a suitable option for increasing animal welfare in tropical climates.

Peripheral fatigue and hormone responses to branched-chain amino acids ingestion and exercise in recovery: a systematic review and meta-analysis.

Branched-chain amino acid (BCAA) can boost anabolism through an increase in the internal concentration of BCAA, which leads to facilitating anabolic hormone release to stimulate the power of the muscles. Studies on administration of BCAA to minimize fatigue substances during long periods of high intensity exercise have been conducted. However, there are disagreements concerning the results of these studies. A comprehensive search was performed on electronic databases up to November 2021 for trials evaluating the effects of BCAA on recovery following exercise. Mean ± standard deviation of follow-up cortisol, insulin, ammonia, and lactate concentrations were extracted to calculate the effect size for meta-analysis. A total of 146 participants for cortisol and 279 participants for lactate were found from the 7 and 15 studies, respectively. The results revealed a significant effect of BCAA supplementation on cortisol concentration during 120≤ min post exercise follow-up. Moreover, without considering follow-up times, an overall analysis showed that BCAA was effective in reducing blood lactate in aerobic exercise and the trained status of athletes. The advantages of BCAA administration relate to a reduction in cortisol concentration after 2h and ameliorated muscle function because of a probable attenuation of fatigue substances immediately after exercise.

Dehorning and welfare indicators in beef cattle: a meta-analysis

Dehorning is a common practice in cattle farming. Researchers suggest that pain during dehorning can be mitigated, although there is no conclusive evidence about the best technique and the best manner of pain relief. A systematic review-meta-analysis was performed to clarify the effect of dehorning on welfare indicators (cortisol concentration or average daily gain or vocalisation) in beef cattle up to 12 months of age. Five electronic databases were systematically searched, as well as conference proceedings and experts were contacted electronically. Pre-defined protocols were applied during all steps of the systematic review process. A random effect meta-analysis was conducted for each indicator separately with the mean of the control and treated groups. Four publications reporting seven studies and 69 trials were included in the MA involving 287 cattle. Heterogeneity between studies was observed for cortisol (I2 = 50.5%), average daily gain (I2 = 70.5%), and vocalisation (I2 = 91.9%). When comparing the non-dehorned group with amputation dehorning, the cortisol concentration was lower 30 min (P &amp;lt; 0.0001) and 120 min (P = 0.023) after procedure (0.767 nmol/L and 0.680 nmol/L, respectively). Local anaesthesia did not show a reduction in cortisol concentration at 30 min after dehorning by amputation. Non-dehorned animals had a tendency to decrease the number of vocalisation (P = 0.081; MD = 0.929) compared with the group dehorned by amputation. These results suggest that dehorning is a painful experience and that local anaesthesia did not alleviate short-term pain following dehorning. Further investigation into pain relief is required to improve confident decision making under practical conditions.

Factors determining the effects of human interaction on the cortisol levels of shelter dogs

The stress experienced by dogs admitted to animal shelters not only impacts welfare, but may lead to behavior that threatens successful adoptions. This stress is reflected in an elevation in the plasma cortisol levels of newly admitted dogs. We previously found 30min of human interaction reduced the plasma cortisol response dogs showed to shelter housing. The goal of the present study was to assess the practicality and effectiveness of the human interaction procedure as a means that volunteers and staff might use to reduce the stress of shelter dogs. We, therefore, investigated several parameters of the effect of human interaction on plasma cortisol concentrations and behavior that were chosen for their relevance to this goal. The current study found that a second day of 30min of petting reduced cortisol levels as effectively as the first (P<0.05) and that 15min of this interaction was as effective as 30min. However, the reduction in cortisol concentrations did not persist when dogs were returned to the home kennel. During petting, signs of excitation (vocalizations) and anxiety (panting) as well as escape attempts were reduced, and social solicitation (tail-wagging) increased (P<0.05 for all behavioral effects). Cortisol reductions were pronounced in dogs admitted as strays (P<0.01), but human interaction did not reduce cortisol levels in a subpopulation relinquished by their owners. We also measured hair cortisol levels to assess stress prior to shelter admittance. Strays and dogs released by their owners showed comparable hair cortisol concentrations that were intermediate to those of pet dogs living in a home and those of dogs diagnosed with Cushing’s disease. These findings show that as little as 15min of human interaction can moderate cortisol levels of shelter dogs. The cortisol reduction is repeatable and associated with positive behavioral change. However the effect is of short duration and appears to vary with the source of the dog. Finally the accumulation of cortisol in hair may be a useful method to estimate the condition of the dog prior to shelter admittance.

ACTH, Cortisol and IL-6 Levels in Athletes following Magnesium Supplementation.

SummaryBackgroundPhysical exercise activates the hypothalamo-pituitary-adrenal (HPA) axis and induces the body’s inflammatory response. Due to contemporary dietary habits and increased energy expenditure, athletes are susceptible to depletion of magnesium ions. The aim of our study was to investigate, through assessment of plasma ACTH, serum IL-6, and salivary/serum cortisol levels, if chronic magnesium supplementation might reduce damaging stress effects in amateur rugby players.MethodsRugby players (N=23) were randomly assigned to intervention and control group. Basal samples were collected before intervention group started a 4-week-long supplementation with magnesium (500 mg Mg/d). Blood and saliva sampling were done a day before the match (Day-1), on the morning of competition (Game), and during a six-day-long recovery period (Day1, Day3 and Day6). ACTH, serum/salivary cortisol, IL-6 and total/differential leukocytes counts were determined at each time point.ResultsThere was a statistically significant increase in ACTH concentration in intervention group compared to control group, while reductions in cortisol concentrations between the two groups were the greatest at Day-1 (p < 0.01) and at the day of competition (Game) (p < 0.01). Our results revealed that magnesium completely abolished the increase in IL-6 level noted in control group on Day1 and Day3 vs. Day-1 (p < 0.01) and also diminished the rise in neutrophil/lymphocyte ratio in intervention group vs. control group (p < 0.01).ConclusionsThese results suggest the possibly important influence magnesium supplementation might have on the change of parameters of HPA axis activity and reduction of immune response activation following strenuous physical exercise such as a rugby game.

Evidence Based Alternative Medicines in Pain Management.

Evidence Based Alternative Medicines in Pain Management.

Inoculation of dogs with a recombinant ACTH vaccine

To determine whether inoculation of healthy dogs with a recombinant peptide containing 3 copies of ACTH would result in the production of antibodies against ACTH and whether this would affect pituitary-adrenocortical function. 8 healthy dogs. A recombinant peptide consisting of 3 copies of ACTH fused to a T-helper cell epitope was produced in Escherichia coli. The protein was inoculated into 4 dogs at 4-week intervals (total of 3 inoculations/dog). Four control dogs received inoculations of PBS solution mixed with adjuvant. Blood samples were collected for determination of antibody titers against ACTH and for measurement of basal and ACTH-stimulated plasma cortisol concentrations. Inoculation with the ACTH vaccine resulted in production of anti-ACTH antibodies in all 4 dogs. Titers were initially high but declined by 15 weeks after the initial inoculation. Basal cortisol concentrations were unaffected by inoculation with the ACTH vaccine. Plasma cortisol concentrations in response to ACTH stimulation were reduced at 12 weeks, but not at 15 weeks, after the first inoculation. Inoculation of dogs with a recombinant ACTH vaccine resulted in the production of antibodies against the hormone. Anti-ACTH titers were initially high but were not sustained. The only detectable endocrine effect in treated dogs was a reduction in cortisol concentration in response to ACTH stimulation in 2 of 4 dogs at 12 weeks after the first inoculation. The effect of vaccine administration on the pituitary-adrenal system was subtle and transient.

Effect of tapering period on plasma hormone concentrations, mood state, and performance of elite male cyclists

In this study, we investigated the effect of 1- and 3-week tapering periods on concentrations of plasma testosterone (T), cortisol (C), T/C ratio, mood state, and performance in elite male cyclists. After 8 weeks of progressive training, cyclists were randomly assigned to a control group (n=12) who continued performing intense training for a further 3 weeks, or a taper group (n=12) who continued with a 50% reduction in training volume. Blood testosterone and cortisol concentrations were assayed and the T/C ratio calculated from analysis obtained via standard ELISA. Mood state was determined using the Profile of Mood States (POMS) questionnaire. All data were collected immediately after a 40-km time-trial performed before, during, and after the 8-week training protocol and after the 1- and 3-week tapering/training periods. In the taper group, 40-km time-trial time decreased significantly (P<0.01) and equally for both the 1- and 3-week taper periods relative to the control group. There were significant elevations in T/C ratio (P<0.001) and reductions in cortisol concentrations and POMS scores in the taper group relative to the control groups at the end of both the 1- and 3-week tapering periods. Hence, taper periods are effective in improving performance and mood state and elevating the blood T/C ratio.

Mirtazapine Acutely Inhibits Salivary Cortisol Concentrations in Depressed Patients

Mirtazapine has been shown to acutely inhibit cortisol secretion in healthy subjects. In the current study, the impact of mirtazapine treatment on salivary cortisol secretion was investigated in 12 patients with major depression (DSM-IV criteria). Patients were treated with mirtazapine for 3 weeks, receiving 15 mg of mirtazapine on day 0, 30 mg on day 1, and 45 mg per day from day 2 to the end of the study (day 21). Response to mirtazapine treatment was defined by a reduction of at least 50% in the Hamilton Rating Scale for Depression after 3 weeks of therapy. Salivary cortisol concentrations were measured before treatment (day -1), at the beginning of treatment (day 0), after 1 week (day 7), and after 3 weeks (day 21) of treatment with mirtazapine. Saliva samples were collected hourly from 8 am to 8 pm. A significant reduction in cortisol concentrations was already noted after 1 day of mirtazapine treatment which was comparable in responders and in nonresponders. Mirtazapine therefore appears to be an effective in decreasing hypercortisolism in depression. However, the importance of the acute inhibitory effects of mirtazapine on cortisol secretion for its antidepressant efficacy has to be further clarified.

Relationship between systemic corticosteroid exposureand growth velocity: development and validation of a pharmacokinetic/pharmacodynamic model

Background: Use of high-dose oral corticosteroids (CSs) can reduce growth velocity (GV) in children, whereas use of low-dose topical CSs has either no effect or transient effects on short-term growth and no effect on final adult height Despite the large body of literature on this topic, some fundamental questions remain concerning the relationship between CS exposure and growth effects. Objectives: The aims of this study were to determine the relationship between CS exposure and GV in children receiving CS therapy for asthma or rhinitis, and to examine whether there is likely to be a link between GV and cortisol suppression. Methods: Data from 32 published studies of the effect on growth of inhaled, intranasal, and oral CSs, includingdelivery by dry powder inhaler, metered-dose inhaler, and aqueous nasal spray, were consolidated by expressing CS exposure in cortisol equivalents using a physiologically based pharmacokinetic/pharmacodynamic approach. The relationship between change in GV and CS exposure in cortisol equivalents was described using a nonlinear sigmoid maximum-effect (E max) model with the following parameters: E max = −5.9 cm/y; steady-state unbound AUC for 50% reduction in GV, in cortisol equivalents = 20,000 ng-h/L; Hill constant= 1.2; and change in GV at zero systemic exposure = 0.06 cm/y. Validation was achieved by comparing the model's predictions with data from 5 studies that were not included in the model development The model was also used to predict the potential of various CS regimens to reduce GV Results: Exploratory data analysis established that change in GV was highly correlated with exposure in cortisol equivalents ( P < 0.001). CSs with high systemic bioavailability by the intranasal route were predicted to have short-term growth effects exceeding the clinical equivalence limit for change in GV (±0.8 cm/y), whereas those with lower bioavailability were predicted to produce systemic exposures below the threshold for significant effects on GV The findings were similar for inhaled CSs and for regimens combining delivery by the intranasal and inhaled routes. In descending order, the model predicted the following ranking of the potential of the various intranasal, inhaled, and oral regimens to reduce GV, expressed as fractions or multiples of the pediatric dose (in μg/d): oral prednisolone 5000 μg/d, 0.14; inhaled beclomethasone dipropionate metered-dose inhaler 400 μg/d, 0.54; inhaled budesonide dry powder inhaler 400 μg/d, 0.66; intranasal triamcinolone acetonide aqueous nasal spray 220 μg/d, 0.74; inhaled triamcinolone acetonide metered-dose inhaler 400 μg/d, 0.75; intranasal beclomethasone dipropionate aqueous nasal spray 336 pg/d, 0.89; inhaled mometasone furoate dry powder inhaler 200 μg/d, 2.4; intranasal budesonide aqueous nasal spray 128 μg/d, 2.5; inhaled fluticasone propionate dry powder inhaler 200 μg/d, 2.6; intranasal mometasone furoate aqueous nasal spray 100 μg/d, 120; and intranasal fluticasone propionate aqueous nasal spray 100 pg/d, 150. Values >1 are predictive of no significant effect on GV The model predicted that a 10% to 15% reduction in plasma cortisol concentration should be detectable at the lower equivalence limit for growth reduction (−0.8 cm/y). The validation procedure showed that the model was capable of predicting the results of the 5 comparative growth studies not included in model development with a correlation coefficient of 0.98. Conclusions: Growth effects appear to be nonlinearly related to CS exposure; therefore, no-effect exposure should be possible for CSs with low systemic exposure. Growth inhibition appears unlikely to occur in the absence of detectable reductions in cortisol concentrations.

The effects of short-term resistance training on endocrine function in men and women.

This investigation examined hormonal adaptations to acute resistance exercise and determined whether training adaptations are observed within an 8-week period in untrained men and women. The protocol consisted of a 1-week pre-conditioning orientation phase followed by 8 weeks of heavy resistance training. Three lower-limb exercises for the quadriceps femoris muscle group (squat, leg press, knee extension) were performed twice a week (Monday and Friday) with every other Wednesday used for maximal dynamic 1 RM strength testing. Blood samples were obtained pre-exercise (Pre-Ex), immediately post-exercise (IP), and 5 min post-exercise (5-P) during the first week of training (T-1), after 6 weeks (T-2) and 8 weeks (T-3) of training to determine blood concentrations of whole-blood lactate (LAC), serum total testosterone (TT), sex-hormone binding globulin (SHBG), cortisol (CORT) and growth hormone (GH). Serum TT concentrations were significantly (P < or = 0.05) higher for men at all time points measured. Men did not demonstrate an increase due to exercise until T-2. An increase in pre-exercise concentrations of TT were observed both for men and women at T-2 and T-3. No differences were observed for CORT between men and women; increases in CORT above pre-exercise values were observed for men at all training phases and at T-2 and T-3 for women. A reduction in CORT concentrations at rest was observed both in men and women at T-3. Women demonstrated higher pre-exercise GH values than men at all training phases; no changes with training were observed for GH concentrations. Exercise-induced increases in GH above pre-exercise values were observed at all phases of training. Women demonstrated higher serum concentrations of SHBG at all time points. No exercise-induced increases were observed in men over the training period but women increased SHBG with exercise at T-3. SHBG concentrations in women were also significantly higher at T-2 and T-3 when compared to T-1 values. Increases in LAC concentrations due to exercise were observed both for men and women for all training phases but no significant differences were observed with training. These data illustrate that untrained individuals may exhibit early-phase endocrine adaptations during a resistance training program. These hormonal adaptations may influence and help to mediate other adaptations in the nervous system and muscle fibers, which have been shown to be very responsive in the early phase of strength adaptations with resistance training.

Cortisol concentrations in serum of borderline hypertensive men exposed to a novel experimental setting

We tested the effect of repeated exposure to a novel experimental setting on resting, morning blood cortisol concentrations in borderline hypertensive men. Borderline hypertension is thought to be accompanied by increased central nervous system activation, which would predict enhanced anticipation and cortisol secretion in a novel experimental situation. Twenty-two borderline hypertensive and 23 normotensive male volunteers were tested in four sessions all separated by 2 or more days. Borderline hypertensives had higher cortisol concentrations than normotensives during the first and second days ( p < .005) but not on the third and fourth days. Significant reductions in cortisol concentrations across days were noticed in borderline hypertensives but not in normotensives. All subjects reported feeling more activated on the first day than on any other day ( p < .01). These results indicate that exposure to a novel experimental situation may enhance secretion of stress related hormones such as cortisol in borderline hypertensives.