Increased Plasma Cortisol Research Articles

Comparison between properties of dorsal and ventral skin mucus in Senegalese sole: Response to an acute stress

Intensive culture of Senegalese sole, Solea senegalensis, represents an option to diversify Mediterranean aquaculture. As a flatfish species, the fish body presents marked asymmetry between the dorsal or ocular side and the ventral or blind side. Taking into account that different surroundings come into contact with each side, in the present study we aimed to compare the properties of skin mucus from both sides, which is the most external barrier and protection for the fish. Skin mucus has recently been proposed as a novel minimally invasive target for the study of physiological responses. Here, a group of ten Senegalese sole were used to measure basal mucus parameters; then four additional groups of ten specimens each were used to study a hypoxia stress challenge (post-stress groups: 15 min-PS, 1 h-PS, 6 h-PS and 24 h-PS), consisting of a 3-minute air exposure. Physicochemical parameters (viscosity, osmolality, pH and main osmotic ions) were analysed in dorsal and ventral mucus. Thereby, mucus components related to stress responses such as cortisol, glucose, lactate, soluble protein and antioxidant power, were measured and compared between the mucus types and in response to hypoxia. Rheograms revealed similar non-Newtonian behaviour of dorsal and ventral mucus viscosities, which suddenly increased in the 15 min-PS group, thus providing fish with immediate insulating and mechanical protection. However, ventral side viscosity of the 24 h-PS group was lower than basal values and its functionality was compromised. Whereas chemical parameters did not differ between sides or in response to hypoxia, components that are soluble in mucus showed asymmetry with soluble protein and lactate being twofold higher in ventral mucus. The classical stress response of increased plasma cortisol accompanying glucose and lactate release was observed. In parallel, mucus glucose and lactate showed rapid but transitory exudation in the 15 min-PS group, while cortisol was detected at minimal levels in skin mucus, and therefore is not recommended as a mucus indicator for this species. Mucus-soluble protein also rose in the 15 min-PS group, which indicates greater exudation of defensive-related proteins. Finally, the antioxidant power of dorsal mucus increased and accumulated, without returning to basal levels. All these findings indicate that flatfish skin mucus properties depend on animal side, and further studies will be necessary to elucidate whether other mucus defensive parameters show this asymmetry and their relevance in these benthonic species.

Effects of Boxing Matches on Metabolic, Hormonal, and Inflammatory Parameters in Male Elite Boxers.

Background and objectives: Boxing is a popular combat sport that requires high intensity and cooperation. However, there are limited data about the influence of boxing matches on blood parameters. The purpose of the present study was to investigate the match-induced changes in the metabolic, hormonal, and inflammatory status in male elite boxers. Materials and methods: High-level 20 male boxers with more than 5 years experience in boxing voluntarily participated in this study. Venous blood samples of the boxers, before and after combat, were taken for determination of the plasma parameters. Results: Our results indicated that a 9-min boxing match caused significant increases in plasma energy fuels (glucose and lactate), metabolic hormones (insulin, adrenocorticotropic hormone (ACTH), cortisol, and growth hormone), inflammatory markers (interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α)), muscle damage indicators (alanine aminotransferase (ALT) and aspartate aminotransferase (AST)), and oxidative stress marker (SOD). A decrease in total oxidant status (TOS) was also considered. However, there were no significant alterations in the plasma levels of androgenic hormone (free and total testosterone), anabolic hormone (IGF-1), lipids (total cholesterol, triglyceride, high-density lipoprotein (HDL), and low-density lipoprotein (LDL)), kidney function markers (creatinine and urea), and minerals (iron (Fe) and magnesium (Mg)). Conclusion: Elevations in the level of energy fuels and metabolic hormones of the boxers could be taken as a reflection of high-energy turnover during combat performance. The increases in inflammatory and tissue damage indicators may possibly be an indication of traumatic injury. Understanding the biochemical changes that occur during boxing match could be valuable to optimize the performance improvement of the athletes.

Transport and Recovery of Gilthead Seabream (Sparus aurata L.) Sedated With Clove Oil and MS-222: Effects on Stress Axis Regulation and Intermediary Metabolism.

Transport processes between aquaculture facilities activate the stress response in fish. To deal with these situations, the hypothalamic-pituitary-interrenal (HPI) axis releases cortisol, leading to an increase in circulating energy resources to restore homeostasis. However, if the allostatic load generated exceeds fish tolerance limits, stress-related responses will compromise health and welfare of the animals. In this context, anesthetics have arisen as potential agents aiming to reduce negative effects of stress response. Here we assessed the effects of a sedative dose of clove oil (CO) and MS-222 on hallmarks involved in HPI axis regulation and energy management after simulated transport, and further recovery, in gilthead seabream (Sparus aurata L.) juveniles. Fish were placed in a mobile setup of water tanks where transport conditions were simulated for 6 h. Sedation doses of either CO (2.5 mg L−1) or MS-222 (5 mg L−1) were added in the water tanks. A control group without anesthetics was also included in the setup. Half of the animals (n = 12 per group) were sampled immediately after transport, while remaining animals were allowed to recover for 18 h in clean water tanks and then sampled. Our results showed that the HPI axis response was modified at peripheral level, with differences depending on the anesthetic employed. Head kidney gene-expressions related to cortisol production (star and cyp11b1) matched concomitantly with increased plasma cortisol levels immediately after transport in CO-sedated fish, but these levels remained constant in MS-222-sedated fish. Differential changes in the energy management of carbohydrates, lipids and amino acids, depending on the anesthetic employed, were also observed. The use of CO stimulated amino acids catabolism, while MS-222-sedated fish tended to consume liver glycogen and mobilize triglycerides. Further studies, including alternative doses of both anestethics, as well as the assessment of time-course HPI activation and longer recovery periods, are necessary to better understand if the use of clove oil and MS-222 is beneficial for S. aurata under these circumstances.

Rosemary leaf powder improved growth performance, immune and antioxidant parameters, and crowding stress responses in common carp (Cyprinus carpio) fingerlings

The present study aimed to investigate the beneficial effects of dietary rosemary leaf powder (RLP) as growth promotor and immunostimulant on plasma immunity as well as stress responses in common carp (Cyprinus carpio) fingerlings. In a 65-day feeding trial, fish were fed on experimental diets containing RLP (0, 1, 2 and 3%). At the end of the experiment, fish performance, survival rate, and proximate composition were investigated. Thereafter, blood samples were collected from treatments for investigation of biochemical and humoral immune parameters. Then, fish were subjected to net-confinement crowding stress for 3 h. Blood samples were collected before and after stress pressure, to measure plasma cortisol and glucose levels. The obtained results showed that fish growth increased along with the increase of dietary RLP levels up to 3%. But proximate composition indices were not influenced by dietary RLP treatments. The RLP-supplemented fish had significantly higher plasma total protein, albumin, globulin, lysozyme, and ACH50 compared to the control group. WBC values were significantly higher in the 2 and 3% RLP-treatments compared to those of the control one. Whereas, fish treated with 3% RLP showed highest plasma total Ig levels. CAT and SOD activities were significantly higher in RLP-supplemented groups than in the control group. Cortisol and glucose levels in all groups were significantly affected by stress; nevertheless, the RLP administration significantly mitigated the stress-induced increase in plasma cortisol and glucose levels. The present results confirmed that the oral administration of RLP has the potential to promote growth performance, enhance antioxidant and immunological parameters, and mitigate the negative effects of crowding stress on common carp fingerlings.

Change in blood stress and antioxidant markers and hydromineral balance of common carp (Cyprinus carpio) anaesthetized with citronellal and linalool: Comparison with eugenol

The present study aimed to investigate the effects of anaesthesia with citronellal and linalool on stress, antioxidant and hydromineral responses of common carp. Eugenol was used as control anaesthetic, as it is a common anaesthetic in aquaculture. The fish (110 ± 5.65 g) were exposed to 406 mg/L citronellal, 982 mg/L linalool or 43 mg/L eugenol within 5 min (short-term anaesthesia) or 10 and 20 mg/L of each anaesthetic for 3 hr (long-term exposure), before blood sampling. The results showed that the short-term anaesthesia had no significant effects on plasma lactate, sodium, chloride and phosphorus levels and blood catalase (CAT) and superoxide dismutase activities. The short-term anaesthesia with linalool led to higher stress responses (increased cortisol and glucose levels) and oxidative stress (increased malondialdehyde [MDA] level and decreased total antioxidant capacity [TAC] and glutathione peroxidase [GPx] activity) compared to the eugenol and citronellal. Citronellal group had significantly higher cortisol and lower TAC level and GPx activity compared to eugenol group. Under the long-term exposure, increase in anaesthetic concentration led to significant increase in plasma cortisol, glucose and phosphorus levels. The linalool-treated fish had significantly higher cortisol and MDA levels compared to the other groups. The eugenol group had significantly higher lactate and phosphorus and lower TAC levels compared to the other groups. Although citronellal causes slight increase in plasma cortisol level, it induces lower tissue damages compared to eugenol. Thus, citronellal might be an alternative anaesthetic for carp anaesthesia based on the present tested parameters.

Effects of dietary arginine supplementation on growth, biochemical, and immunological responses of common carp (Cyprinus carpio L.), stressed by stocking density

The present study aimed to investigate interaction effects of dietary arginine and stocking density on common carp (Cyprinus carpio) growth performance, stress response, innate immunity and immune gene expression. Three diets with deficient (4.1% of dietary protein; DA), optimum (5.3% of dietary protein; OA) and surplus (8.1% of dietary protein; SA) arginine levels were formulated. The diets were offered for 30 days to common carp reared at two different stocking densities, 10 or 20 g/L. Then blood leukocyte count, and plasma cortisol, glucose, total protein, globulin, total immunoglobulin (Ig), lysozyme and complement (ACH50), and head kidney interleukin-1 beta (IL-1beta), interleukin-8 (IL-8) and tumor necrosis factor-alpha (TNF-a) were determined. Results showed that increased stocking density led to decreased growth performance; similarly, both DA and SA groups had significantly lower growth performance compared to the OA group. Increased stocking density led to increased plasma cortisol, glucose, lysozyme, proteins and ACH50 and decreased plasma total Ig and blood WBC, and the head kidney’ cytokine genes expression. Both DA and SA groups had significantly higher plasma cortisol and glucose, and lower plasma lysozyme, proteins, ACH50, and head kidney's cytokine gene expression compared to the OA treatment; the SA group had more adverse effects on these parameters than the DA group. Dietary arginine at optimum level significantly inhibited the stress-induced cortisol and lysozyme elevation and mitigated the stress-induced IL-1beta and IL-8 genes down-regulation. In conclusion, dietary arginine deficient or surplus levels significantly impair common carp growth performance and health conditions. Moreover, surplus dietary arginine level has no benefit on the fish growth and health under high stocking density condition.

Investigation of Antistress Activity of Operculina Terpethum Roots using Various Experimental Models

The root part of Operculina terpethum has been widely used in Ayurveda to treat variety of common and stress related disorders. The antistress effect of a seven-days treatment (100 and 200 mg / kg, p.o.) of the 80% ethanolic extract of Operculina terpethum root (OTRE) was evaluated by using the swimming endurance test, anoxic tolerance test, and biochemical changes in the cold-restraint stress test. The immunomodulatory activity was also evaluated for the same doses, and treatment of OTRE using the hem agglutination test. Diazepam 1 mg/kg was used as reference standard for the comparison. Both the doses of OTRE showed anti stress activity in all the tested models. 7 days pretreatment of OTRE (100 and 200 mg / kg, p.o.) treated animals showed a decrease in immobility time and an increase in anoxic tolerance time in swimming endurance and the anoxic tolerance tests, respectively. Pretreatment with OTRE significantly ameliorated the cold restraint stress induced variation in biochemical level such as increase in plasma cholesterol, triglyceride, glucose, total protein, and cortisol. Further, OTRE treatment significantly inhibited cold restraint stress induced alteration in brain noradrenaline, dopamine and serotonin levels. In mice immunized with sheep red blood cells, the treatment groups subjected to restraint stress prevented the humoral immune response to the antigen. The immune stimulating activity of the OTRE was indicated by an increase in the antibody titer in mice pre-immunized with sheep red blood cells and subjected to restraint stress. The findings of the present investigations indicate that the OTRE has significant anti stress activity, which may be due to the immune stimulating property and increased resistance, nonspecifically, against all experimental stress conditions.

Effects of temperament on growth, plasma cortisol concentrations and puberty attainment in Nelore beef heifers

Excitable temperament disrupts physiological events required for reproductive development in cattle, but no research has investigated the impacts of temperament on growth and puberty attainment in Bos indicus females. Hence, this experiment evaluated the effects of temperament on growth, plasma cortisol concentrations and puberty attainment in B. indicus heifers. A total of 170 Nelore heifers, weaned 4 months before the beginning of this experiment (days 0 to 91), were managed in two groups of 82 and 88 heifers each (mean ± SE; initial BW=238±2 kg, initial age=369±1 days across groups). Heifer temperament was evaluated via exit velocity on day 0. Individual exit score was calculated within each group by dividing exit velocity into quintiles and assigning heifers with a score from 1 to 5 (1=slowest; 5=fastest heifer). Heifers were classified according to exit score as adequate (ADQ, n=96; exit score⩽3) or excitable temperament (EXC, n=74; exit score>3). Heifer BW, body condition score (BCS) and blood samples were obtained on days 0, 31, 60 and 91. Heifer exit velocity and score were recorded again on days 31, 60 and 91. Ovarian transrectal ultrasonography was performed on days 0 and 10, 31 and 41, 60 and 70, 81 and 91 for puberty evaluation. Heifer was declared pubertal at the first 10-day interval in which a corpus luteum was detected. Exit velocity and exit score obtained on day 0 were correlated (r⩾0.64, P<0.01) with evaluations on days 31, 60 and 91. During the experiment, ADQ had greater (P<0.01) mean BCS and BW gain, and less (P<0.01) mean plasma cortisol concentration compared with EXC heifers. Temperament × time interactions were detected (P<0.01) for exit velocity and exit score, which were always greater (P<0.01) in EXC v. ADQ heifers. A temperament × time interaction was also detected (P=0.03) for puberty attainment, which was delayed in EXC v. ADQ heifers. At the end of the experiment, a greater (P<0.01) proportion of ADQ were pubertal compared with EXC heifers. In summary, B. indicus heifers classified as EXC had reduced growth, increased plasma cortisol concentrations and hindered puberty attainment compared to ADQ heifers. Moreover, exit velocity may serve as temperament selection criteria to optimize development of B. indicus replacement heifers.

Oxygen Uptake and Osmotic Balance of Atlantic Salmon in Relation to Exercise and Salinity Acclimation

The fish gill is subject to an osmorespiratory compromise in physiologically demanding situations where conditions that favour gas exchange may compromise osmotic balance, especially when large gradients between the blood and the aquatic environment are present. Fish in isosmotic water should therefore be less restricted by an osmorespiratory compromise, which should improve aerobic performance. To investigate this hypothesis, Atlantic salmon were acclimated to freshwater, near isosmotic brackish water or sea water, and tested in groups of 10 in a large swim tunnel respirometer to assess metabolic rates, swimming capacity and haematological parameters. Oxygen uptake rates and the critical swimming speed were similar between treatments. However, osmolality and plasma [ions] before and after swim trials, and subsequent recovery differed. Fish in sea water experienced a substantially larger osmotic disturbance in the swim trials, which had increased further 3 hours post-fatigue, while fish in lower salinities were approaching full recovery. Swim trials increased plasma cortisol levels, which may modulate increased gas transfer and facilitate beneficial ion regulation in both low and high salinities. Swimming also increased haematocrit and haemoglobin concentration that returned to control levels after recovery, suggesting recruitment of erythrocytes via splenic contraction. These results show that Atlantic salmon do not elicit a clear salinity optimum in terms of metabolic and locomotory advantages. Although, swimming in sea water imposes larger osmoregulatory challenges which may have implications for repeated swim challenges. Hence, Atlantic salmon are well-equipped to minimize the potential restrictions of an osmorespiratory compromise on aerobic performance, and more so in brackish and freshwater.

Physiological responses of anti-predation in prey fish to the threat of piscivorous fish in different underwater visibility conditions

ABSTRACT Considering that the anti-predation behaviour of prey fishes may vary with predator hunting strategy, we experimentally investigated the physiological responses of Astyanax bimaculatus (Linnaeus, 1758) shoals to the presence of two piscivorous fish species with different hunting modes: sit-and-wait and active pursuit. In addition, we evaluated the influence of underwater visibility conditions on the interaction between predator and prey. We tested the hypotheses that: (i) prey plasma cortisol and glucose levels vary according to piscivore hunting strategy, and (ii) no reduction in plasma glucose and cortisol levels takes place in turbid environments due to the inability of prey to accurately recognise predators by non-visual signals. The results revealed that the presence of piscivorous fish increased plasma cortisol levels in prey, with no significant difference recorded between the two hunting strategy treatments. We also observed no significant change in plasma glucose levels in different water transparency conditions. Thus, we conclude that physiological changes in the selected prey fish do not vary with predator hunting mode, and it is therefore necessary to consider the ability of the prey to recognise and evaluate danger, regardless of piscivore hunting strategy.

Developmental Programming of Capuchin Monkey Adrenal Dysfunction by Gestational Chronodisruption.

In the capuchin monkey (Cebus apella), a new-world nonhuman primate, maternal exposure to constant light during last third of gestation induces precocious maturation of the fetal adrenal and increased plasma cortisol in the newborn. Here, we further explored the effects of this challenge on the developmental programming of adrenal function in newborn and infant capuchin monkeys. We measured (i) plasma dehydroepiandrosterone sulphate (DHAS) and cortisol response to ACTH in infants with suppressed endogenous ACTH, (ii) plasma DHAS and cortisol response to ACTH in vitro, and (iii) adrenal weight and expression level of key factors in steroid synthesis (StAR and 3β-HSD). In one-month-old infants from mothers subjected to constant light, plasma levels of cortisol and cortisol response to ACTH were twofold higher, whereas plasma levels of DHAS and DHAS response to ACTH were markedly reduced, compared to control conditions. At 10 months of age, DHAS levels were still lower but closer to control animals, whereas cortisol response to ACTH was similar in both experimental groups. A compensatory response was detected at the adrenal level, consisting of a 30% increase in adrenal weight and about 50% reduction of both StAR and 3β-HSD mRNA and protein expression and the magnitude of DHAS and cortisol response to ACTH in vitro. Hence, at birth and at 10 months of age, there were differential effects in DHAS, cortisol production, and their response to ACTH. However, by 10 months of age, these subsided, leading to a normal cortisol response to ACTH. These compensatory mechanisms may help to overcome the adrenal alterations induced during pregnancy to restore normal cortisol concentrations in the growing infant.

Post-exposure effects of the piscicide 3-trifluoromethyl-4-nitrophenol (TFM) on the stress response and liver metabolic capacity in rainbow trout (Oncorhynchus mykiss).

The piscicide 3-trifluoromethyl-4-nitrophenol (TFM) has been used to control invasive sea lamprey (Petromyzon marinus) populations in the Great Lakes for almost 60 years. Applied to rivers and streams containing larval lampreys, TFM seldom harms non-target fishes, but the effects of sub-lethal treatments on fish physiology are not well understood. We examined the effects of 9 h exposure to TFM on the stress axis and liver metabolic capacity of rainbow trout (Oncorhynchus mykiss) using in vivo and in vitro approaches. The fish that had been acutely exposed to TFM in vivo had increased plasma cortisol levels at 12 h post-treatment, but TFM exposure did not interfere with in vitro cortisol production in head kidney preparations. Subjecting trout to an acute handling stressor 12 h post-TFM exposure resulted in a relative attenuation of the plasma cortisol and glucose response compared to pre-stress levels. We conclude that routine TFM treatments can lead to elevations of plasma cortisol following exposure, plus a relative dampening of the stress response in rainbow trout, with high cortisol levels lasting at least 12 h post-treatment. Since the ability of the fish to produce cortisol and the liver metabolic capacity were not compromised following TFM exposure, it is likely that their ability to cope with other stressors is not altered in the long-term.

Effects of new plant based anesthetics Origanum sp. and Eucalyptus sp. oils on stress and welfare parameters in Dicentrarchus labrax and their comparison with clove oil

The effects of two new anesthetics (essential oils) extracted from oregano (OO) and eucalyptus (EO) plants were studied in European sea bass (Dicentrarchus labrax) stress response and welfare parameters in comparison to the effects of clove oil (CO) that is one of the most used anesthetics in aquaculture. A time-course study on evolution of plasma cortisol after anesthesia was conducted. Relative expression of stress-related genes, including glucocorticoid receptor (gr), heat shock protein 70 and 90 (hsp70, hsp90) steroidogenic acute regulatory protein (star), cytochrome 11B (cyp11b1) and hypoxia inducible factor (hif) was determined in liver, gills and head kidney after anesthesia.After anesthetic use, there was a time effect on plasma cortisol concentration, with highest values registered after 2 h for all the experimental groups. EO induced a secondary increase of plasma cortisol 24 h after the use of this anesthetic. Hsps expression level in gills was high at 0 h in EO fish group, whereas hif expression increased after 2 h of exposure in CO fish. In hepatic tissue, gr expression increased after 24 h in the EO group. In head kidney tissue, expression of steroidogenesis-related genes star and cyp11b1 increased in EO fish group, whereas in the OO group, the expression of the same genes decreased at 2 h and 24 h of exposure. Although the three anesthetics generally showed similar patterns of variation of all analyzed parameters, results indicate that EO could be deleterious for welfare, whereas OO affects fish welfare to a lesser extent than CO and EO. Overall, these results show that OO could be a good anesthetic for fish based on greater effectiveness, lower optimum concentration and less impact on fish stress.

Effects of dietary inclusions of red beet and betaine on the acute stress response and muscle lipid peroxidation in rainbow trout.

This study evaluates the effects of red beet (RB) and betaine on rainbow trout submitted to an acute stress challenge. A control diet was compared with four experimental diets in which red beet (14 and 28%) and betaine (0.9 and 1.63%) were incorporated in different concentrations according to a factorial design. Cortisol in plasma and fin, glucose and lactate plasma levels, and malondialdehide (MDA) in muscle were all measured before the stress challenge and 30min and 6 and 12h after the stress challenge as parameters to determine the diet effects. RB and betaine had no effect on cortisol, glucose, and MDA basal levels. However, lactate basal levels were significantly lower on fish fed with RB and betaine. Thirty minutes after the stress challenge, there was a significant increase in plasma and fin cortisol, glucose and lactate concentrations, although fish fed with diets containing RB and betaine showed significantly higher plasma cortisol values. MDA values of fish fed with 14% RB and 0.9% betaine were significantly higher than MDA values from fish fed with 28% RB and 1.63% betaine. After 6 and 12h, plasma and fin cortisol and lactate levels recovered in a similar trend. Glucose plasma levels recovered in almost all groups 12h after the stress. Also, MDA values recovered basal levels after 6 and 12h. RB and betaine did not enhance the tolerance to the stress challenge compared to the control group, although the presence of these ingredients had no negative effect on any of the stress indicators.

Effect of Obesity or Metabolic Syndrome and Diabetes on Osseointegration of Dental Implants in a Miniature Swine Model: A Pilot Study

The increasing prevalence of obesity or metabolic syndrome (O/MS) and type 2 diabetes mellitus (DM) remains a global health concern. Clinically relevant and practical translational models mimicking human characteristics of these conditions are lacking. This study aimed to demonstrate proof of concept of the induction of stable O/MS and type 2 DM in a Göttingen minipig model and validate both of these disease-adjusted Göttingen minipig models as impaired healing models for the testing of dental implants. Nine minipigs were split into 3 groups-control (normal diet), obese (cafeteria diet), and diabetic (cafeteria diet plus low-dosage streptozotocin)-followed by placement of dental implants. Inflammatory markers including tumor necrosis factor α, C-reactive protein, and cortisol were recorded for each study group. Removal torque was measured, and histomorphometric analysis (bone-to-implant contact and bone area fraction occupancy) was performed. O/MS pigs showed, on average, a 2-fold increase in plasma C-reactive protein (P<.05) and cortisol (P<.09) concentrations compared with controls; DM pigs showed, on average approximately, a 40-fold increase in plasma tumor necrosis factor α levels (P<.05) and a 2-fold increase in cortisol concentrations (P<.05) compared with controls. The impact of O/MS and DM on implants was determined. The torque to interface failure was highest in the control group (200N-cm) and significantly lower in the O/MS (90 N-cm) and DM (60 N-cm) groups (P<.01). Bone formation around implants was significantly greater in the control group than in the O/MS and DM groups (P<.02). Both O/MS and DM minipigs express a human-like disease phenotype, and both presented bone-healing impairment around dental implants. Our finding of no significant difference between type 2 DM and O/MS in bone formation around implants provides evidence that further investigation of the impact of O/MS is warranted.

Effects of age and exercise on inflammatory cytokines, HSP70 and HSP90 gene expression and protein content in Standardbred horses

We hypothesised that the cortisol response to acute exercise, markers of oxidative stress, expression of inflammatory cytokines, heat shock protein (HSP)70 and HSP90 expression in whole blood and skeletal muscle, and HSP70 and HSP90 protein concentrations in skeletal muscle are altered by age and in response to acute submaximal exercise in horses. Young (n=6; 5.5±2.8 year) and aged (n=6; 22.6±2.25 year) unconditioned Standardbred mares underwent an acute submaximal exercise test. Blood samples were collected and analysed for plasma cortisol and malondialdehyde (MDA) concentrations, and for cytokine and HSP gene expression pre- and post-exercise. Gluteus medius biopsies were obtained for analysis of cytokine and HSP gene expression pre- and at 0, 4, 24 and 48 h post-exercise. Data were analysed for main effects using a two-way ANOVA for repeated measures. Post-hoc comparisons of means were conducted using Student-Neuman-Keuls for pair-wise multiple comparisons where appropriate. Acute submaximal exercise increased plasma cortisol concentration in both young and aged mares, and the duration of the post-exercise rise in cortisol was altered in aged horses. Plasma MDA concentration and expression of tumour necrosis factor-α (TNF-α) and interleukin (IL)-6 were unchanged in blood and muscle. Exercise increased IL-1β expression in whole blood of young and aged mares, with young mares having greater exercise-induced expression at 2 (P&lt;0.001) and 4 (P=0.019) h post-exercise. Both young and aged horses had increased HSP70 expression in whole blood following acute exercise, with young horses exhibiting 3-fold greater HSP70 expression than aged mares at 2 h post-exercise. HSP90 expression in whole blood following exercise was increased only in young horses. Both young and aged horses had increased HSP90 expression in skeletal muscle following exercise, but there was no difference due to age. However, the timing of HSP70 expression was different between young and aged horses. The age-related changes in cortisol and IL-1β expression following acute submaximal exercise can have implications for energy homeostasis and the adaption to such disturbances at a cellular and whole animal level. Quantification of HSP expression in whole blood may be a useful biomarker, with implications for cellular adaptation and survival in aged horses.

Potential Biomarkers with Plasma Cortisol, Brain-derived Neurotrophic Factor and Nitrites in Patients with Acute Ischemic Stroke

Acute Ischemic Stroke (AIS) represents an economic challenge for health systems all over the globe. Changes of neuroactive steroids have been found in different neurological diseases. We have previously demonstrated that old patients with AIS show changes of plasma cortisol and estradiol concentrations, in that increased steroid levels are associated with a deterioration of neurological status and a worse cognitive decline. The present study assessed in patients with AIS if changes of behavior, Brain-Derived Neurotrophic Factor (BDNF) and Nitrites (NO-2) bear a relationship with the degree of hypercortisolism. We recruited patients hospitalized within the first 24 hours of AIS. Subjects were divided into two groups, each one composed of 40 control subjects and 40 AIS patients, including men and women. The neurological condition was assessed using the National Institute of Health Stroke Scale (NIHSS) and the cognitive status with the Montreal Cognitive Assessment (MoCA). The emotional status was evaluated using the Montgomery-Asberg Depression Rating Scale (MADRS), whereas the Modified Rankin Scale (MRS) was used to determine the functional condition. BDNF and NO-2 plasma levels were measured by ELISA and the Griess reaction method, respectively. We found that in AIS patients, increased plasma cortisol was negatively correlated with plasma BDNF and NO-2 levels, neurological condition, cognition, functional responses and emotional status, suggesting a relationship between the declines of clinical, behavioral and blood parameters with stress-induced cortisol elevation. Nitrites and BDNF may represent potential biomarkers for cortisol negative effects on the area of cerebral ischemia and penumbra, potentiating ischemic cell damage.

Effect of testosterone replacement on feeding behaviors after acute and chronic stress in gonadectomized male NMRI mice

We study the role of gonadectomy on the response to unavoidable stress and the role of testosterone replacement on gonadectomy in the male Naval Medical Research Institute mice (30±5 g) were studied. For this purpose, the hormonal and metabolic changes were investigated. In the experimental group, the gonads were surgically removed, and a cannula was inserted into the left lateral ventricle. For acute and chronic stress induction, animals were placed in the communication box for 30 min for one day and four consecutive days, respectively. The animals received different doses of intraventricular (ICV) testosterone (0.01, 0.05, 0.1 μg/mouse) 5 minutes or intraperitoneal (IP) testosterone (0.05, 0.01, 0.1 mg/kg) 30 minutes before the stress induction. The results showed that acute and chronic stress increases plasma cortisol concentration. IP testosterone injections of testosterone did not decrease cortisol concentrations in response to acute stress, whereas ICV injections did reduce cortisol concentrations. The stress reduced anorexia time, while the administration of testosterone increased anorexia time. In addition, acute stress reduced food intake in the gonadectomized mice. IP testosterone at 0.01 and 0.05 mg/kg increased food intake. Additionally, stress in gonadectomized mice reduced water intake, while the IP injection of testosterone in chronic stress further reduced water intake. Also, stress reduced the animals’ brain/adrenal volumes, while the IP and ICVinjection of testosterone at 0.01 mg/kg inhibited this effect. The results showed that the IP (0.05, 0.01, 0.1 mg/kg) and ICV (0.01, 0.05, 0.1 μg/mouse) administration of testosterone in the gonadectomized mice can modulate hormonal and metabolic changes induced by stress.

Inflammation-mediated muscle metabolic dysregulation local and remote to the site of major abdominal surgery

SummaryBackground & aimsPostoperative hyperglycaemia is common in patients having major surgery and is associated with adverse outcomes. This study aimed to determine whether bacteraemia contributed to postoperative systemic inflammation, and whether increases in the expression of muscle mRNAs and proteins reflecting increased muscle inflammation, atrophy and impaired carbohydrate oxidation were evident at the time of surgery, and both local and distant to the site of trauma, and could be associated with impaired glucoregulation.MethodsFifteen adult patients without diabetes undergoing major abdominal surgery participated in this observational study set in a university teaching hospital. Arterialised-venous blood samples and muscle biopsies were obtained before and after major elective abdominal surgery, from sites local (rectus abdominis – RA) and remote to the site of surgery (vastus lateralis – VL). The main outcome measures included blood glucose concentrations, gut permeability and changes in expression of muscle mRNAs and proteins linked to inflammation and glucose regulation.ResultsImmediately postoperatively, RA demonstrated markedly increased mRNA expression levels of cathepsin-L (7.5-fold, P < 0.05), FOXO1 (10.5-fold, P < 0.05), MAFbx (11.5-fold, P < 0.01), PDK4 (7.8-fold, P < 0.05), TNF-α (16.5-fold, P < 0.05) and IL-6 (1058-fold, P < 0.001). A similar, albeit blunted, response was observed in VL. Surgery also increased expression of proteins linked to inflammation (IL-6; 6-fold, P < 0.01), protein degradation (MAFbx; 4.5-fold, P < 0.5), and blunted carbohydrate oxidation (PDK4; 4-fold, P < 0.05) in RA but not VL. Increased systemic inflammation (TNF-α, P < 0.05; IL-6, P < 0.001), and impaired postoperative glucose tolerance (P < 0.001), but not bacteraemia (although gut permeability was increased significantly, P < 0.05) or increased plasma cortisol, were noted 48 h postoperatively.ConclusionsA systemic postoperative proinflammatory response was accompanied by muscle inflammation and metabolic dysregulation both local and remote to the site of surgery, and was not accompanied by bacteraemia.Clinical trial registrationRegistered at http://clinicaltrials.gov (NCT01134809).

Physiological and behavioural evaluation of common anaesthesia practices in the rainbow trout

Anaesthetic drugs are commonly administered to fish in aquaculture, research and veterinary contexts. Anaesthesia causes temporary absence of consciousness and may reduce the stress and/or pain associated with handling and certain invasive procedures. The rainbow trout (Oncorhynchus mykiss) is a widely-used model species with relevance to both aquaculture and natural ecosystems. This study sought to establish the relative acute impact of commonly used anaesthetics on rainbow trout when used for anaesthesia or euthanasia by exploring their effects on aversion behaviour and stress physiology. Five widely used anaesthetics were investigated at two concentrations reflective of common laboratory practises: MS-222, benzocaine, 2-phenoxyethanol, etomidate and eugenol. The anaesthetics were administered via immersion and fish were: 1) euthanised with anaesthetic; or 2) allowed to recover from deep plane anaesthesia; or 3) subjected to a conditioned place avoidance paradigm. Behaviour, opercular beat rate and plasma cortisol concentrations and cortisol release rates to water were quantified to investigate the effects of the five drugs. Based upon longer induction to deep plane anaesthesia, and increased plasma cortisol levels post-anaesthesia the widely-used and recommended anaesthetic MS-222 may be relatively stressful for rainbow trout. Whereas 2-phenoxyethanol, due to a combination of quicker induction, reduced aversive behavioural response during anaesthesia and lower post-anaesthesia plasma cortisol levels may be a more advisable alternative. It is crucial for the welfare of fish that the use of anaesthetics is as humane as possible and thus these findings have important implications for the welfare and husbandry of captive rainbow trout.