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BACKGROUND: Working memory is a fundamental cognitive process that is critically involved in planning, comprehension, reasoning, and problem solving. Acute stress has been shown to impair working memory. This stress-induced working memory deficit has profound implications for cognitive functioning in everyday life as well as for stress-related mental disorders. Here, we tested whether a cognitive training intervention would make working memory more resistant to disruptive effects of acute stress. METHODS: In a preregistered, fully crossed between-subjects design with the factors stress (vs. control) and cognitive training (vs. sham), 123 healthy men and women (ages 18-35 years) completed a daily cognitive training program targeting working memory-related processes or a sham training over a period of 6 weeks. After this 6-week training intervention, participants underwent a standardized stress or control manipulation shortly before their working memory performance was tested. RESULTS: As expected, the exposure to acute stress led to a significant working memory impairment in the sham training group. Critically, although the subjective, autonomic, and endocrine stress responses were comparable in the 2 training groups, this stress-induced working memory impairment was abolished in the intervention training group. CONCLUSIONS: These results are the first to show that a cognitive training intervention directed at prefrontal and hippocampal functioning can prevent the detrimental effects of stressful events on working memory performance.

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BACKGROUND: Sweeteners and sweetness enhancers (S&SE) are used to replace energy yielding sugars and maintain sweet taste in a wide range of products, but controversy exists about their effects on appetite and endocrine responses in reduced or no added sugar solid foods. The aim of the current study was to evaluate the acute (1 day) and repeated (two-week daily) ingestive effects of 2 S&SE vs. sucrose formulations of biscuit with fruit filling on appetite and endocrine responses in adults with overweight and obesity. METHODS: In a randomised crossover trial, 53 healthy adults (33 female, 20 male) with overweight/obesity in England and France consumed biscuits with fruit filling containing 1) sucrose, or reformulated with either 2) Stevia Rebaudioside M (StRebM) or 3) Neotame daily during three, two-week intervention periods with a two-week washout. The primary outcome was composite appetite score defined as [desire to eat + hunger + (100 - fullness) + prospective consumption]/4. FINDINGS: Each formulation elicited a similar reduction in appetite sensations (3-h postprandial net iAUC). Postprandial insulin (2-h iAUC) was lower after Neotame (95% CI (0.093, 0.166); p < 0.001; d = -0.71) and StRebM (95% CI (0.133, 0.205); p < 0.001; d = -1.01) compared to sucrose, and glucose was lower after StRebM (95% CI (0.023, 0.171); p < 0.05; d = -0.39) but not after Neotame (95% CI (-0.007, 0.145); p = 0.074; d = -0.25) compared to sucrose. There were no differences between S&SE or sucrose formulations on ghrelin, glucagon-like peptide 1 or pancreatic polypeptide iAUCs. No clinically meaningful differences between acute vs. two-weeks of daily consumption were found. INTERPRETATION: In conclusion, biscuits reformulated to replace sugar using StRebM or Neotame showed no differences in appetite or endocrine responses, acutely or after a two-week exposure, but can reduce postprandial insulin and glucose response in adults with overweight or obesity. FUNDING: The present study was funded by the Horizon 2020 program: Sweeteners and sweetness enhancers: Impact on health, obesity, safety and sustainability (acronym: SWEET, grant no: 774293).

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Spa therapy consists of multiple techniques based on the healing effects of water, including hydrotherapy, balneotherapy, and mud therapy, often combined with therapeutic exercises, massage, or physical therapy. Balneotherapy is a clinically effective complementary approach in the treatment of low-grade inflammation- and stress-related pathologies, especially rheumatic conditions due to its anti-inflammatory properties. The main objective of this investigation was to conduct a systematic review analyzing the available evidence on the effect of spa therapy on serotonin and dopamine function. The databases PubMed, Web of Science, Scopus, and Cochrane Central Register of Controlled Trials (CENTRAL) were used from June to July 2023. Exclusion criteria were (1) articles not written in English, (2) full text not available, (3) article not related to the objective of the review. JADAD scale was used for methodological quality evaluation. Four studies were included in the systematic review. Two studies were related to serotonin in healthy individuals, one to serotonin in fibromyalgia, and one to dopamine in healthy individuals. One of the studies evaluated hydrotherapy, another one balneotherapy and mud-bath therapy, and the other two assessed balneotherapy interventions. Studies were very heterogeneous, and their methodological quality was low, making it difficult to draw clear conclusions regarding the effect of spa therapy on peripheral serotonin and dopamine function. The findings of this review highlight the lack of studies evaluating these neurotransmitters and hormones in the context of spa therapy. Further research is needed to evaluate the potential effects of these therapies on serotonin or dopamine function.

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Background: Chemotherapy, used either before or after surgery, has significantly improved survival in early breast cancer. Accurate risk assessment is essential to avoid both overtreatment and undertreatment. This review provides an overview of the evolution of chemotherapy as well as risk factors for tailored systemic therapies in early breast cancer - from pathologic risk factors to gene expression signatures to endocrine response assessment. Summary: Chemotherapy has improved dramatically in recent decades from its beginnings with conventionally dosed cyclophosphamide plus methotexate plus 5-fluorouracil to dose-dense anthracycline- and taxane-containing regimens. Similarly, risk assessment has evolved starting from traditional pathologic risk factors such as tumor size, axillary nodal status, and grading. In recent decades, gene expression signatures have improved prognostic accuracy with a high level of evidence. In turn, these signatures can be further improved by incorporating the aforementioned pathologic factors. As an important step away from this static assessment, dynamic assessment of proliferation factor Ki-67 after short-term preoperative endocrine treatment has gained interest to improve risk assessment in early hormone receptor-positive breast cancer. Key Message: This review highlights advances in chemotherapy and risk assessment in early breast cancer, from pathologic risk factors for recurrence to gene expression signatures and endocrine response assessment. These developments are leading to better risk stratification and thus better adaptation of therapies.

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Global warming is a significant threat to the sustainability and profitability of the dairy sector, not only in tropical or subtropical regions but also in temperate zones where extreme summer temperatures have become a new and challenging reality. Prolonged exposure of dairy cows to high temperatures compromises animal welfare, increases morbidity, and suppresses fertility, resulting in devastating economic losses for farmers. To counteract the deleterious effects of heat stress, cattl e employ various adaptive thermoregulatory mechanisms including molecular, endocrine, physiological, and behavioral responses. These adaptations involve the immediate secretion of heat shock proteins and cortisol, followed by a complex network of disrupted secretion of metabolic and reproductive hormones such as prolactin, ghrelin, ovarian steroid, and pituitary gonadotrophins. While the strategic heat stress mitigation measures can restore milk production through modifications of the microclimate and nutritional interventions, the summer fertility records remain at low levels compared to those of the thermoneutral periods of the year. This is because sustainment of high fertility is a multifaceted process that requires appropriate energy balance, undisrupted mode of various hormones secretion to sustain the maturation and fertilizing competence of the oocyte, the normal development of the early embryo and unhampered maternal-embryo crosstalk. In this review, we summarize the major molecular and endocrine responses to elevated temperatures in dairy cows, as well as the impacts on maturing oocytes and early embryos, and discuss the consequences that heat stress brings about in dairy cattle fertility.

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Various studies on immobilized BALB/c mice to evaluate changes in hormone levels associated with stress responses have advanced the characterization of multiple aspects of the biological actions of extremely low-frequency (ELF) electric fields (EFs). In this study, we aimed to investigate the effect of mouse posture on its stress responses and evaluate the importance of adjusting the stress degree in the model. Mice were immobilized inside centrifuge tubes and exposed to an ELF EF generated between parallel plate electrodes. Blood was collected under anesthesia immediately after EF exposure, and plasma glucocorticoids were assayed. The inhibitory effects of EFs on glucocorticoid elevation by immobilization were reproduced regardless whether mice were in the abdominal or lateral recumbent position, for the EF vector delivered to mice through the sagittal or frontal plane. The effect of ELF EF was reproduced in moderately and mildly stressed mice but not in severely immobilized mice. Hence, adjusting the stress degree is critical to the reproducibility of the results for this model. We characterized the effects of ELF EF on homeostasis, including the stress response, and provided valuable information for the scientific evaluation of the biological risks and medical applications of ELF EF.

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Adipose tissue is characterized as an endocrine organ that acts as a source of hormones and paracrine factors. In diseases such as cancer, endocrine and paracrine signals from adipose tissue contribute to cancer progression. Young individuals with estrogen receptor-alpha positive (ER-α+) breast cancer (BC) have an increased resistance to endocrine therapies, suggesting that alternative estrogen signaling is activated within these cells. Despite this, the effects of stromal age on the endocrine response in BC are not well defined. To identify differences between young and aged ER-α+ breast tumors, RNA sequencing data were obtained from The Cancer Genome Atlas. Analysis revealed enrichment of matrix and paracrine factors in young (≤40 years old) patients compared to aged (≥65 years old) tumor samples. Adipose-derived stromal/stem cells (ASCs) from noncancerous lipoaspirate of young and aged donors were evaluated for alterations in matrix production and paracrine secreted factors to determine if the tumor stroma could alter estrogen signaling. Young and aged ASCs demonstrated comparable proliferation, differentiation, and matrix production, but exhibited differences in the expression levels of inflammatory cytokines (Interferon gamma, interleukin [IL]-8, IL-10, Tumor necrosis factor alpha, IL-2, and IL-6). Conditioned media (CM)-based experiments showed that young ASC donor age elevated endocrine response in ER-α+ BC cell lines. MCF-7 ER-α+ BC cell line treated with secreted factors from young ASCs had enhanced ER-α regulated genes (PGR and SDF-1) compared to MCF-7 cells treated with aged ASC CM. Western blot analysis demonstrated increased activation levels of p-ER ser-167 in the MCF-7 cell line treated with young ASC secreted factors. To determine if ER-α+ BC cells heightened the cytokine release in ASCs, ASCs were stimulated with MCF-7-derived CM. Results demonstrated no change in growth factors or cytokines when treated with the ER-α+ secretome. In contrast to ER-α+ CM, the ER-α negative MDA-MB-231 derived CM demonstrated increased stimulation of pro-inflammatory cytokines in ASCs. While there was no observed change in the release of selected paracrine factors, MCF-7 cells did induce matrix production and a pro-adipogenic lineage commitment. The adipogenesis was evident by increased collagen content through Sirius Red/Fast Green Collagen stain, lipid accumulation evident by Oil Red O stain, and significantly increased expression in PPARγ mRNA expression. The data from this study provide evidence suggesting more of a subtype-dependent than an age-dependent difference in stromal response to BC, suggesting that this signaling is not heightened by reciprocal signals from ER-α+ BC cell lines. These results are important in understanding the mechanisms of estrogen signaling and the dynamic and reciprocal nature of cancer cell-stromal cell crosstalk that can lead to tumor heterogeneity and variance in response to therapy.

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In BALB/c mice, immobilization-increased plasma glucocorticoid (GC) levels are suppressed by extremely low frequency (ELF) electric fields (EF). The aim of this study was to advance our understanding of the biological effects of ELF-EF, using its suppressive effect on the GC response. Mice were exposed to a 50 Hz EF of 10 kV/m via a parallel plate electrode and immobilized as needed. We examined the suppressive effect of ELF-EF on GC level change after repeated immobilizations, electrode polarization, and EF shielding of different portions of the mouse body parts. Additionally, bodyweight changes owing to stress and EF were examined. Immobilization-induced reduction in the plasma GC levels was reproduced in mice with stress and EF exposure, regardless of the stress episode numbers and electrode polarization. Furthermore, when the head of mice was shielded from the EF, the suppressive effect was possibly relatively lower than that when the abdomen was shielded. The bodyweight of the mice decreased for 3 days after immobilization before recovering; ELF-EF did not affect the bodyweight. Thus, to elicit the biological effects of the EF, not only the size of the area where the EF is distributed but also the area where the field is distributed should be important. The results also confirmed the stableness of the present experimental system, at least in terms of the stress-reducing effect. In addition, the restriction in this study caused weight loss, but ELF-EF was not considered to affect it. The results improve the understanding of the biological effect and medical applications of ELF-EF.

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The sub-lethal toxicity of Captan® on selected haematological (Hemoglobin, Haematocrit, Mean Corpuscular Hemoglobin) growth (Condition factor, Hepatosomatic Index, Specific Growth Rate), biochemical (serum glucose, protein), and endocrine parameters (growth hormone, T3 and T4) in Clarias batrachus was examined under chronic exposures. Captan® was administered at predetermined exposure concentrations (0.53 and 1.06 mg/L) and monitored on days 15, 30, and 45 of the experimental periods. The experimental groups showed significantly lower values (p < 0.05) of haemoglobin content, hematocrit, MCH in Captan® exposed fish compared to control. Serum protein, k-factor and SGR were significantly lower in exposed fish. Endocrine responses (T3 and T4) emerged as the most sensitive biomarker category, depicting modulated responses between sub-chronic exposure at day-15 and chronic responses at day-45. In general, biomarker depictions indicate that Captan® exposures are capable of inducing stress-specific effects at the biochemical and physiological levels negatively impacting the overall health and longevity of such animals.

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Background: Despite low aggressiveness in tumor biology and high responsiveness to endocrine therapy, subgroups of patients with estrogen receptor-positive/HER2-negative (ER+/HER2-) breast cancer relapse early in the first two years after initiation of endocrine therapy, indicating potential endocrine resistance. Accordingly, we attempted to establish a scoring system to inform the first-2-year prognosis (F2P Score). Methods: Patients with node-negative ER+/HER2- breast cancer and complete data of gene expressions in a 21-gene panel were retrospectively retrieved from Shanghai Jiao Tong University Breast Cancer Database (SJTU-BCDB). The F2P Score was established based on the clinical and genomic variables associated with the first-2-year relapse after shrinkage correction and validated using the bootstrap resampling method. Model performance was quantified by Harrell's concordance-index (C-index) and Bayesian information criteria (BIC). Results: The F2P Score was established by integrating the clinical (age and tumor size) and genomic (ESR1, PGR, BCL2, CD68, GSTM1, and BAG1) variables with a C-index of 0.71 and BIC of 397.46. Bootstrap C-index was 0.72 (95% CI, 0.62-0.81) and BIC was 396.75 (95% CI, 252.37-541.13). A higher score indicated an increased likelihood of a first-2-year relapse, when used as continuous (HR, 2.94; 95% CI, 1.87-4.61) or categorical (HR, 3.68; 95% CI, 1.70-8.00) predictors in multivariate analysis. Both continuous and categorical F2P Score also remained prognostic for overall survival and other endpoints. No significant interaction was observed between the F2P Score and treatment subgroups. Additionally, the F2P Score outperformed the IHC4, clinical treatment score and 21-gene test in predicting first-2-year relapse. Conclusion: The F2P Score reported herein, integrating the clinicopathological and genomic variables, may inform prognosis and endocrine responsiveness. After the benefits and risks have been considered, treatment escalation may be an alternative strategy for patients with a higher score.

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Invasive lobular breast carcinoma (ILC) accounts for 10% to 15% of breast cancers diagnosed annually. Evidence suggests that some aspects of endocrine treatment response might differ between invasive ductal carcinoma (IDC) and ILC, and that patients with ILC have worse long-term survival. We analyzed The Cancer Genome Atlas dataset and observed lower levels of ESR1 mRNA (P = 0.002) and ERα protein (P = 0.038) in ER+ ILC (n = 137) compared to IDC (n = 554), and further confirmed the mRNA difference in a local UPMC cohort (ILC, n = 143; IDC, n = 877; P < 0.005). In both datasets, the correlation between ESR1 mRNA and ERα protein was weaker in ILC, suggesting differential post-transcriptional regulation of ERα. In vitro, 17ß-estradiol (E2) decreased the rate of degradation and increased the half-life of ERα in ILC cell lines, whereas the opposite was observed in IDC cell lines. Further, E2 failed to induce robust ubiquitination of ERα in ILC cells. To determine the potential clinical relevance of these findings, we evaluated the effect of 2 selective estrogen receptor downregulators (SERDs), ICI 182,780 and AZD9496, on ERα turnover and cell growth. While ICI 182,780 and AZD9496 showed similar effects in IDC cells, in ILC cell lines, AZD9496 was not as effective as ICI 182,780 in decreasing ERα stability and E2-induced proliferation. Furthermore, AZD9496 exhibited partial agonist activity in growth assays in ILC cell lines. Our study provides evidence for a distinct ERα regulation by SERDs in ILC cell lines, and therefore it is important to include ILC models into preclinical and clinical testing of novel SERDs.

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Atypical antipsychotics (AAP) or second-generation antipsychotics are the clinical option for schizophrenia treatment during acute psychoses, but they are also indicated for maintenance during lifetime, even though they are being used for other psychiatric conditions in clinical practice such as affective disorders and autism spectrum disorder, among others. These drugs are differentiated from typical antipsychotics based on their clinical profile and are a better choice because they cause fewer side effects regarding extrapyramidal symptoms (EPS). Even though they provide clear therapeutic benefits, AAP induce peripheral effects that trigger phenotypic, functional, and systemic changes outside the Central Nervous System (CNS). Metabolic disease is frequently associated with AAP and significantly impacts the patient's quality of life. However, other peripheral changes of clinical relevance are present during AAP treatment, such as alterations in the immune and endocrine systems as well as the intestinal microbiome. These less studied alterations also have a significant impact in the patient's health status. This manuscript aims to revise the peripheral immunological, endocrine, and intestinal microbiome changes induced by AAP consumption recommended in the clinical guidelines for schizophrenia and other psychiatric disorders.

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Adrenal responsiveness was tested in nonpregnant, lactating Holstein dairy cows fed diets supplemented with OmniGen-AF (OG; Phibro Animal Health Corp., Teaneck, NJ), an immune modulator, and in nonsupplemented control (CON) cows following bolus infusions of a combination of corticotropin-releasing hormone (CRH; 0.3 µg/kg of BW) and arginine vasopressin (VP; 1.0 µg/kg of BW) or ACTH (0.1 IU/kg of BW) in 2 environments: thermoneutral [TN; temperature-humidity index (THI) <60] for 24 h/d and heat stress (HS; THI >68 for 17 h/d). Cows (506) were initially fed OG (n = 254) or CON (n = 252) diets for 44 d before selection of a subgroup of cows (n = 12; 6 OG, 6 CON) for the study. The 2 subgroups were balanced for parity, milk yield, and days in milk. All cows were transported to and housed in 2 environmentally controlled rooms at the University of Arizona Agricultural Research Complex (Tucson). Cows were given 3 d to acclimate to the rooms and then underwent 12 d of TN conditions and then 8 d of HS conditions for a total of 24 d on experiment. Cows were infused with CRH-VP on d 9 of TN and on d 1 of HS and with ACTH on d 10 of TN and on d 2 of HS. Hormone infusions took place at 1000 h (0 h) on each infusion day. Blood samples, taken in 30-min intervals, were first collected at 0800 h (-2 h) and were drawn until 1800 h (8 h). Before infusion, serum progesterone was elevated in OG cows compared with CON cows. Infusion of releasing factors (CRH-VP or ACTH) caused increases in serum cortisol and progesterone, but cortisol release was greater in CON cows than in OG cows during HS, whereas progesterone did not differ between the 2 treatments. Serum ACTH increased following infusion of releasing factors, but this increase was greater following CRH-VP infusion than ACTH infusion. Serum bovine corticosteroid-binding globulin also increased following infusion of releasing factors in both treatment groups, but this increase was greater during HS in cows fed OG. The free cortisol index (FCI) increased following CRH-VP and ACTH and was higher in HS than in TN for both OG and CON cows. However, the FCI response was blunted in OG cows compared with CON cows during HS. Heat stress enhanced the adrenal response to releasing factors. Additionally, the adrenal cortisol and FCI response to releasing factors was reduced during acute heat stress in cows fed OG. Collectively, these data suggest that OG supplementation reduced the adrenal responsiveness to factors regulating cortisol secretion during acute HS.

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This study aimed to compare the effects of 2 resistance training (RT) programs with different velocity losses (VLs) allowed in each set: 10% (VL10%) versus 30% (VL30%) on neuromuscular performance and hormonal response. Twenty-five young healthy males were randomly assigned into 2 groups: VL10% (n = 12) or VL30% (n = 13). Subjects followed a velocity-based RT program for 8 weeks (2 sessions per week) using only the full-squat (SQ) exercise at 70%-85% 1-repetition maximum (1RM). Repetition velocity was recorded in all training sessions. A 20-m running sprint, countermovement jump (CMJ), 1RM, muscle endurance, and electromyogram (EMG) during SQ exercise and resting hormonal concentrations were assessed before and after the RT program. Both groups showed similar improvements in muscle strength and endurance variables (VL10%: 7.0%-74.8%; VL30%: 4.2%-73.2%). The VL10% resulted in greater percentage increments in CMJ (9.2% vs. 5.4%) and sprint performance (-1.5% vs. 0.4%) than VL30%, despite VL10% performing less than half of the repetitions than VL30% during RT. In addition, only VL10% showed slight increments in EMG variables, whereas no significant changes in resting hormonal concentrations were observed. Therefore, our results suggest that velocity losses in the set as low as 10% are enough to achieve significant improvements in neuromuscular performance, which means greater efficiency during RT. Novelty The VL10% group showed similar or even greater percentage of changes in physical performance compared with VL30%. No significant changes in resting hormonal concentrations were observed for any training group. Curvilinear relationships between percentage VL in the set and changes in strength and CMJ performance were observed.

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We developed an experimental system to characterize the suppressive effect of extremely low-frequency (ELF) electric fields (EFs) on the stress response. We assessed differences in the EF effects by age and gender. Control, EF-alone, immobilization-alone, and co-treated groups were subjected to an EF (50 Hz, 10 kV/m). Co-treated mice were exposed to the EF for 60 min, with immobilization during the latter half. Our results indicate that the suppressive effects of ELF EFs on the stress response in immobilized mice occur regardless of gender or age. As stress plays an important role in the onset and progression of various diseases, these findings may have broad implications for understanding the efficacy of EFs in animal, and perhaps human, health. Bioelectromagnetics. 2020;41:156-163. © 2019 Bioelectromagnetics Society.

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Landscape disturbances can alter habitat structure and resource availability, often inducing physiological responses by organisms to cope with the changing conditions. Quantifying the endocrine stress response through measurement of glucocorticoids has become an increasingly common method for determining how organisms physiologically respond to challenges imposed by their environment. We tested the hypothesis that Eastern Fence Lizards cope with fire disturbance effects by modulating their secretion of corticosterone (CORT). We measured the baseline and stress-induced plasma CORT of male Eastern Fence Lizards in a chronosequence of fire-altered habitats (recently burned, recovering from burn, and unburned). Although habitat use by lizards differed among burn treatments, including differences in use of canopy cover, leaf litter, and vegetation composition, we did not detect a significant effect of fire-induced habitat alteration on plasma CORT concentration or on body condition. In addition, we found no effect of blood draw treatment (baseline or stress-induced), body temperature, body condition, or time taken to collect blood samples on concentration of plasma CORT. Low intensity burns, which are typical of prescribed fire, may not be a sufficient stressor to alter CORT secretion in Eastern Fence Lizards (at least during the breeding season). Instead, lizards may avoid allostatic overload using behavioral responses and by selecting microsites within their environment that permit thermoregulatory opportunities necessary for optimal performance and energy assimilation.

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High rearing densities are typical conditions of both inland and onshore intensive aquaculture units. Despite obvious drawbacks, this strategy is nonetheless used to increase production profits. Such conditions inflict stress on fish, reducing their ability to cope with disease, bringing producers to adopt therapeutic strategies. In an attempt to overcome deleterious effects of chronic stress, Senegalese sole, Solea senegalensis, held at low (LD) or high density (HD) were fed tryptophan-supplemented diets with final tryptophan content at two (TRP2) or four times (TRP4) the requirement level, as well as a control and non-supplemented diet (CTRL) for 38 days. Fish were sampled at the end of the feeding trial for evaluation of their immune status, and mortalities were recorded following intra-peritoneal infection with Photobacterium damselae subsp. piscicida. Blood was collected for analysis of the hematological profile and innate immune parameters in plasma. Pituitary and hypothalamus were sampled for the assessment of neuro-endocrine-related gene expression. During the feeding trial, fish fed TRP4 and held at LD conditions presented higher mortalities, whereas fish kept at HD seemed to benefit from this dietary treatment, as disease resistance increased over that of CTRL-fed fish. In accordance, cortisol level tended to be higher in fish fed both supplemented diets at LD compared to fish fed CTRL, but was lower in fish fed TRP4 than in those fed TRP2 under HD condition. Together with lower mRNA levels of proopiomelanocortin observed with both supplementation levels, these results suggest that higher levels of tryptophan might counteract stress-induced cortisol production, thereby rendering fish better prepared to cope with disease. Data regarding sole immune status showed no clear effects of tryptophan on leucocyte numbers, but TRP4-fed fish displayed inhibited alternative complement activity (ACH50) when held at LD, as opposed to their HD counterparts whose ACH50 was higher than that of CTRL-fed fish. In conclusion, while dietary tryptophan supplementation might have harmful effects in control fish, it might prove to be a promising strategy to overcome chronic stress-induced disease susceptibility in farmed Senegalese sole.

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OBJECTIVES: The present study verified the effect of moderate-to-high-intensity aerobic exercise on the endocrine response profile and adipose tissue in young healthy men with different phenotype characteristics. DESIGN: Eighteen men were divided into three experimental groups with defined body components and specific physical fitness: Endurance phenotype - EP (n = 6; low body mass; low fat content; aerobic endurance trained), Athletic phenotype - AP (n = 6; high body mass; low fat content, resistance trained), Obesity phenotype - OP (n = 6; high body mass; high fat content, untrained). METHODS: The participants performed an progressive exercise protocol on a treadmill (30% VO2max, 50% VO2max, 70% VO2max), separated by 45 s of passive rest for blood collection. RESULTS: Plasma glucose oxidation increased in relation to exercise intensity, but to a greater extent in the AP group. The free fatty acids' plasma level decreased with a rise in exercise intensity, but with different kinetics in particular phenotypes. Plasma growth hormone increased after the cessation of exercise and was significantly higher in all groups 45 min into recovery compared to resting values. Plasma insulin decreased during exercise in all groups, but in the OP, the decrease was blunted. CONCLUSIONS: The results indicate that the rate of lipolysis, hormonal and metabolic response to aerobic exercise depends on the individuals' phenotype. Thus, exercise type, duration and intensity have to be strictly individualized in relation to phenotype in order to reach optimal metabolic benefits.

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The pituitary is a central organ of the neuro-endocrine system in fish that plays critical roles in various physiological processes, including stress response and behavior. Although it is known that pituitary hormones can have a direct or indirect influence stimulating or suppressing the immune responses, whether there is a local immune response in the pituitary or what is the effect of the immune stimulus on the pituitary function in fish is unknown. With the aim to understand the interaction between the immune responses and the endocrine axes at the pituitary level, particularly the Hypothalamus-Pituitary-Interrenal (HPI) axis, pituitaries of rainbow trout (Oncorhynchus mykiss) were cultured in vitro, incubated with bacterin, or bacterin plus CRH, cortisol, human recombinant IL1ß, or spleen medium for 3 h, and then genes involved in pro-inflammation (il1ß, il8, tnfα1, ifnγ), anti-inflammation (tgfß1b, il10), immune modulation (mhcIIa, c3, mif) and stress response (crhbp, pomca, pomcb, gr1) were tested. Data showed that, incubation with bacterin alone and bacterin plus recombinant IL1ß or CRH, as well as medium from bacterin treated spleen caused significant up-regulation of pro-inflammatory genes il1ß and il8, while down-regulated the anti-inflammatory gene tgfß1b. Besides, recombinant IL1ß plus bacterin or alone caused raise of mhcIIa and tnfa, respectively. On the contrary, just a slight or even no alteration was recorded in the expression of stress response genes including crhbp, pomca, pomcb and gr1 in the in vitro cultured trout pituitary following this stimulation. These results suggest a local immune gene equipment in the pituitary of fish, and the potential for fish pituitary to develop both innate and adaptive immune responses, whereas that immune stimulation was not able to evoke a significant endocrine stress response in vitro.

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BACKGROUND: Stress can be defined as an acute threat to the homeostasis of an organism, and in order to manage stress, and maintain stability, the allostatic systems activate an adaptive response. Stress has been shown to have both short - and long-term effects on the function of the gastrointestinal tract, but long-term exposure to stress is more likely to cause endocrine disorders. OBJECTIVE: The aim of this study was to investigate the endocrine response to stress, and evaluate the relationship between somatization and gastrointestinal symptoms. METHODS: A systematic literature search was conducted on several academic databases, which included, Pubmed, EBSCO and Science Direct. The search was performed using the keywords, "endocrine response to stress", "somatization" and "gastrointestinal symptoms". RESULTS: The hypothalamic-pituitary-adrenal (HPA) axis is essential in controlling physiological stress responses. Dysfunction is related to several mental disorders, including anxiety and depression, or somatization. Symptoms associated with genetic, or other traumatic experiences of individuals under stress, can lead to a maladaptive response to stress. These stressful life events were found to be associated with digestive system-related chronic diseases. Gastrointestinal disorders significantly affect millions of people worldwide. CONCLUSION: This study examined how the endocrine system responds to stress, and the effect this has in causing stress-related gastrointestinal distresses. Our findings indicate that stress-related psychological disorders are strongly associated with the severity of gastrointestinal symptoms.

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