Increased Plasma Cortisol Levels Research Articles

Investigating the biological relevance of measuring gastrointestinal cortisol metabolite levels to assess stress responses in Atlantic salmon (Salmo salar L.) after an acute stress

Monitoring stress levels of farmed Atlantic salmon (Salmo salar) is important to ensure fish welfare and optimize farm operations. Feces could be a promising matrix for assessing stress responses in fish, based on their properties of low-invasive sampling and allowing repeated sampling over time. Meanwhile, elevated levels of cortisol metabolites (CMs) in feces indicate the increases in plasma cortisol levels (PLA) after exposure to acute stress. However, the dynamics of fecal CMs following acute stress in Atlantic salmon remain unclear. In this study, a confinement stress involving chasing and crowding was conducted to investigate the responses of gastrointestinal CMs to an acute stressor in Atlantic salmon. The post-smolts, with an average weight of 155.21 g, were sampled before and at 30 min, 1.5, 6, 12, 18, 24, 36, and 48 h after the onset of stress. Blood and gastrointestinal contents from the stomach, proximal intestine, and distal intestine of each fish were collected and subsequently analyzed, using competitive enzyme-linked immunosorbent assay (ELISA). The results demonstrated that the pre-stress level of PLA was low (4.28 ± 6.13 ng/ml) and reached a peak within 30 min following stress. The levels of CMs in gastrointestinal contents from stomach (SCMs), proximal intestine (PCMs), and distal intestine (DCMs) in pre-stress group were 0.82 ± 0.50, 18.31 ± 6.14 and 16.04 ± 6.69 ng/g, respectively. Gastrointestinal CMs increased significantly within 30 min and the peak levels of SCMs (3.51 ± 3.75 ng/g), PCMs (68.19 ± 23.71 ng/g) and DCMs (65.67 ± 23.37 ng/g) were found at 1.5 h post-stress. The significant increases in PCMs and DCMs post-stress validate the biological relevance of measuring intestinal CMs for assessing acute stress responses in Atlantic salmon. No significant difference was noted between PCMs and DCMs across all samples, suggesting that intestinal contents can serve as a suitable matrix compared with feces when measuring the responses of CMs to acute stress. The time lag between the peak of PLA levels and their reflection in the intestinal contents exceeded 1 h, indicating that using intestinal contents as a matrix to assess stress levels in fish can extend and delay the sampling window. This study highlights valuable guidance for determining the optimal times to utilize intestinal contents for measuring stress responses, providing further insights into the dynamics of fecal CM following acute stress.

The behavioral and neurobiological response to sound stress in salmon.

Noise associated with human activities in aquatic environments can affect the physiology and behavior of aquatic species which may have consequences at the population and ecosystem levels. Low frequency sound is particularly stressful for fish, since it is an important factor in predator-prey interactions. Even though behavioral and physiological studies have been conducted to assess the effects of sound on fish species, neurobiological studies are still lacking. In this study we exposed farmed salmon to low frequency sound for 5 minutes a day for 30 trials and conducted behavioral observations and tissue sampling before sound exposure (timepoint zero; T0) and after 1 (T1), 10 (T2), 20 (T3) and 30 (T4) exposures, to assess markers of stress. These included plasma cortisol, neuronal activity, monoaminergic signaling, and gene expression in 4 areas of the forebrain. We found that sound exposure induced an activation of the stress response by eliciting an initial startle behavioral response, together with increased plasma cortisol levels and a decrease in neuronal activity in the hypothalamic tubercular nuclei (TN). At T3 and T4 salmon showed a degree of habituation in their behavioral and cortisol response. However, at T4, salmon showed signs of chronic stress with increased serotonergic activity levels in the dorsolateral and dorsomedial pallium, the preoptic area, and the TN, as well as an inhibition of growth and reproduction transcripts in the TN. Together, our results suggest that prolonged exposure to sound results in chronic stress that leads to neurological changes which suggest a reduction of life fitness traits.

POSTERIOR REVERSIBILE LEUKOENCEPHALOPATHY SYNDROME AND HYPERTENSIVE CRISIS DUE TO OBSTRUCTIVE SLEEP APNEA:SEARCHING FOR A LINK

Objective: Posterior Reversible Encephalopathy Syndrome(PRES) is a clinic-radiological syndrome characterized by headache, nausea/vomiting, confusion, cognitive changes, seizures,cortical blindness. MRI shows bilateral hyper-intense lesions at the parieto-occipital sub-cortical level on T2 and FLAIR sequences. PRES is associated with severe hypertension, while obsstructive sleep apnesa(OSA) is a common cause of secondary hypertension but rarely causes hypertensive encephalopathy. We present a case of a 42-year-old woman who suffered of hypertensive emergency during hospitalization for dyspnea. Design and method: Clinical history revealed obesity, COPD, OSA in treatment with CPAP, HF with depressed EF (44%), adrenal hyperplasia and retroduodenal lesion under investigation. She was active smoker and BP was uncontrolled by valsartan 160 mg, furosemide 25 mg,bisoprolol 2,5 mg. During the hospitalization in November 2023, patient presented headache, seizures, respiratory distress with high BP values (220/120 mmHg, HR 78 bpm). Results: Laboratory tests revealed only a mild increase of plasma cortisol levels (27.5 mcg/dL, range 0-24); low-dose overnight dexamethasone suppression test was normal (1.5 mcg/dl). Despite anti-hypertensive therapy with B-blocker urinary metanephrine levels were normal (184 mcg/24 h, range 0-320) and 18f-FDG PET-TAC for retroduodenal lesion was normal. Cerebral CT did not show ischemic or hemorrhagic lesions while MRI documented radiological characteristics compatible with PRES (Figure 1). Electroencephalogram showed no epileptic abnormalities. Antihypertensive intravenous treatment with urapidil (25 mg as bolus injection followed by 25 mg/h as continuous infusion) was performed for 36h and followed by oral treatment with canrenoate 25 mg, amlodipine 5 mg and doxazosin 4 mg, added to the above therapy. At discharge, BP was normalized (120/84 mmHg). Checking the electronic card of CPAP, the patient used the device for more than four hours only in 35% of the nights. Conclusions: OSA is a risk factor for acute cardiovascular and cerebrovascular diseases like PRES. CPAP application has been shown to induce small reductions (about 3 mmHg) in BP, but in clinical practice the adherence of treatment is very low (30-60%). On the other hand, the improvement of BP values during hospitalization, raises the suspicion that adherence to pharmacological treatment at home was in the same way poor.

Pubertal glyphosate-based herbicide exposure aggravates high-fat diet-induced obesity in female mice.

Glyphosate-based herbicides (GBH) are the most widely used pesticides globally. Studies have indicated that they may increase the risk of various organic dysfunctions. Herein, we verified whether exposure to GBH during puberty increases the susceptibility of male and female mice to obesity when they are fed a high-fat diet (HFD) in adulthood. From the 4th-7th weeks of age, male and female C57Bl/6 mice received water (CTL group) or 50mg GBH /kg body weight (BW; GBH group). From the 8th-21st weeks of age, the mice were fed a standard diet or a HFD. It was found that pubertal GBH exposure exacerbated BW gains and hyperphagia induced by HFD, but only in female GBH-HFD mice. These female mice also exhibited high accumulation of perigonadal and subcutaneous fat, as well as reduced lean body mass. Both male and female GBH-HFD displayed hypertrophic white adipocytes. However, only in females, pubertal GBH exposure aggravated HFD-induced fat accumulation in brown adipocytes. Furthermore, GBH increased plasma cortisol levels by 80% in GBH-HFD males, and 180% in GBH-HFD females. In conclusion, pubertal GBH exposure aggravated HFD-induced obesity, particularly in adult female mice. This study provides novel evidence that GBH misprograms lipid metabolism, accelerating the development of obesity when individuals are challenged by a second metabolic stressor, such as an obesogenic diet.

Impacts of Temperature on the Growth, Feed Utilization, Stress, and Hemato-Immune Responses of Cherry Salmon (Oncorhynchus masou).

Cherry salmon (Oncorhynchus masou) hold commercial value in aquaculture, and there is a need for controlled laboratory studies to isolate the specific effects of temperature on their growth, feeding, and well-being. We examined the effects of different temperatures (10 °C, 14 °C, 18 °C, and 22 °C) on juvenile cherry salmon (average mass 29.1 g) in triplicate tanks per treatment over eight weeks. The key parameters assessed included growth rate, feed efficiency, stress response, and hemato-immune responses. Our objectives were to determine the most and less favorable temperatures among the four designated temperatures and to assess the adverse effects associated with these less favorable temperatures. The results showed that body weight, growth rates, feed intake, and feed efficiency were significantly higher at 10 °C and 14 °C compared to 18 °C and 22 °C. Reduced appetite and feeding response were observed at 22 °C. Red blood cell parameters were significantly lower at 22 °C. At 10 °C, the results showed significantly increased plasma cortisol levels, gill Na+/K+-ATPase activity, body silvering, and decreased condition factors, suggesting potential smoltification. The potential smoltification decreased with increasing temperatures and disappeared at 22 °C. Furthermore, the plasma lysozyme concentrations significantly increased at 18 °C and 22 °C. In conclusion, our study identifies 10 °C and 14 °C as the temperatures most conducive to growth and feed performance in juvenile cherry salmon under these experimental conditions. However, temperatures of 22 °C or higher should be avoided to prevent compromised feeding, reduced health, disturbed immune responses, impaired growth, and feed performance.

Oral glutamine supplementation relieves muscle loss in immobilized rats, altering p38MAPK and FOXO3a signaling pathways

BackgroundSkeletal muscle synthesizes, stores, and releases body L-glutamine (GLN). Muscle atrophy due to disabling diseases triggers the activation of proteolytic and pro-apoptotic cell signaling, thus impairing the body's capacity to manage GLN content. This situation has a poor therapeutic prognosis. ObjectiveEvaluating if oral GLN supplementation can attenuate muscle wasting mediated by elevated plasma cortisol and activation of caspase-3, p38MAPK, and FOXO3a signaling pathways in soleus and gastrocnemius muscles of rats submitted to 14-day bilateral hindlimbs immobilization. MethodsAnimals were randomly distributed into six groups: non-immobilized rats (Control), control orally supplemented with GLN (1 g kg−1) in solution with L-alanine (ALA: 0.61 g kg−1; GLN+ALA), control orally supplemented with dipeptide L-alanyl-L-glutamine (DIP; 1.49 g kg−1), hindlimbs immobilized rats (IMOB), IMOB orally GLN+ALA supplemented (GLN+ALA-IMOB), and IMOB orally DIP supplemented (DIP-IMOB). Plasma and muscle GLN concentration, plasma cortisol level, muscle caspase-3 activity, muscle p38MAPK and FOXO3a protein content (total and phosphorylated forms), and muscle cross-sectional area (CSA) were measured. ResultsCompared to controls, IMOB rats presented: a) increased plasma cortisol levels; b) decreased plasma and muscle GLN concentration; c) increased muscle caspase-3 activity; d) increased total and phosphorylated p38MAPK protein content; e) increased FOXO3a and decreased phosphorylated FOXO3a protein content; f) reduced muscle weight and CSA befitting to atrophy. Oral supplementation with GLN+ALA and DIP was able to significantly attenuate these effects. ConclusionsThese findings attest that oral GLN supplementation in GLN+ALA solution or DIP forms attenuates rats' skeletal muscle mass wasting caused by disuse-mediated muscle atrophy.

Using behavioral observations in freestalls and at milking to improve pain detection in dairy cows after lipopolysaccharide-induced clinical mastitis

This study aimed to determine the effect of lipopolysaccharide (LPS)-induced mastitis with or without nonsteroidal anti-inflammatory drug (NSAID) on dairy cows' clinical, physiological, and behavioral responses in the milking parlor and freestalls as well as the specificity (Sp) and sensitivity (Se) of behavioral responses in detecting cows with LPS-induced mastitis. Twenty-seven cows received an intramammary infusion of 25 µg of Escherichia coli LPS in 1 healthy quarter. Following LPS infusion, 14 cows received a placebo (LPS cows), and 13 cows received 3 mg/kg of body weight of ketoprofen i.m. (LPS+NSAID cows). Cow response to the challenge was monitored at regular intervals from 24 h before to 48 h postinfusion (hpi) through direct clinical observations, markers of inflammation in milk, and via point-in-time direct behavioral observations in the barn and at milking. In LPS cows, infusion induced a significant increase of plasma cortisol levels at 3 and 8 hpi, milk cortisol levels at 8 hpi, somatic cell counts from 8 to 48 hpi, IL-6 and IL-8 at 8 hpi, milk amyloid A (mAA) and haptoglobin at 8 and 24 hpi, rectal temperature at 8 hpi, and respiratory rate at 8 hpi. Their rumen motility rate decreased at 8 and 32 hpi. Compared with before the challenge, significantly more LPS cows stopped feeding/ruminating and pressed their tail between their legs at 3 and 5 hpi, increased feeding/ruminating at 24 hpi, and had the tendency to be less responsive, dropping their head, and dropping their ears at 5 hpi. At milking, compared with before challenge, significantly more LPS cows lifted their hooves at forestripping at 8 hpi. The 2 groups showed similar patterns of response for milk cortisol, somatic cell count, respiratory rate, mAA, haptoglobin, and IL-6, IL-1β, and IL-8. Compared with LPS cows, LPS+NSAID cows had significantly lower plasma cortisol levels at 3 hpi, their rectal temperature decreased at 8 hpi, their rumen motility rate increased at 8 and 32 hpi, and their heart rate increased at 32 hpi. Compared with LPS cows, a significantly larger proportion of LPS+NSAID cows were feeding/ruminating, a lower proportion had ears down at 5 hpi, and a larger proportion lied down at 24 hpi. At milking, whatever the phase of milking, for "hoof to belly," 9 out of 14 cows did not show this behavior before infusion (Sp = 64%) and 14/14 did not kick during pre-infusion milking (Sp = 100%). Regarding sensitivity, at maximum, 5 cows out of 14 (Se = 36%) displayed "hoof to belly" after infusion. For "lifting hoof," 14/14 did not show hoof-lifting before infusion (Sp = 100%) and 6/14 displayed it after infusion (Se = 43%) at forestripping only. In the freestall barn, 9 behaviors had a Sp >75% (at minimum, 10/14 did not show the behavior) whatever the time point but Se < 60% (at maximum, 8/14 displayed the behavior). Finally, "absence of feeding and ruminating" had Sp of 86% (12/14 ate/ruminated) and Se of 71% (10/14 did not eat/ruminate) at 5 hpi. This study shows that feeding/ruminating, tail position, and reactivity at forestripping could be used as behavioral indictors for early detection of mastitis-related pain in dairy cows.

Effect of Spring and Summer Seasons on Some Bio-physiological Markers in Buffaloes

Background: The purpose of this study was to ascertain the effects of the hot, dry spring and summer weather on the endocrinological and biochemical properties of buffaloes with the help of physiological as well as biochemical analysis. Methods: Like plasma glucose using GOD-POD kits, total plasma protein using Autospan kits, Blood Urea Nitrogen using MBK Urea kits DAM assay, cortisol hormone by bovine cortisol enzyme linked immunosorbent assay kit etc. Result: During the summer season, there was a significant (P less than 0.01) reduction in plasma glucose level (mg/dl), blood urea nitrogen level (mg/dl) and plasma total protein level (g/dl) in comparison to the spring season, but there was a significant (P less than 0.01) increase in plasma cortisol level in the summer in comparison to the spring season in all three districts. From the current study, it can be inferred that heat stress negatively affects the adaptability and metabolic reactions of buffalo.

Levobupivacaine versus levobupivacaine – dexmedetomidine for ultrasound guided bilateral superficial cervical plexus block for upper tracheal resection and reconstruction surgery under general anesthesia

ABSTRACT Background Anesthesia for repair of tracheal stenosis considered as a challenging that needs to optimize the immediate postoperative period and preventing unwise use of postoperative opioid. This study was designed to evaluate the analgesic efficacy of adding dexmedetomidine to levobupivacaine for blocking the superficial cervical plexus for tracheal reconstruction. Methods Eighty patients, underwent elective surgical repair of upper tracheal stenosis and reconstruction. Patients were randomly allocated into two groups and received ultrasound guided bilateral superficial cervical plexus block. Group L received 10 ml of 0.5% Levobupivacaine. Group D received 10 ml of 0.5% Levobupivacaine and 0.5 µg⁄kg dexmedetomidine in each side. The total postoperative analgesic consumption, postoperative pain severity and the time to the first analgesic requirement were evaluated in all patients. Results Total postoperative fentanyl consumption decreased in group D (76.75 ± 9.57 µg) versus (176.75 ± 22.66 µg) in group L with p value ≤ 0.001 and time to first analgesic requirement was longer in group D (20.70 ± 5.42 hours) versus (8.35 ± 2.55 hours) in group L. Moreover, increased plasma cortisol level during surgery and after recovery in group L compared with group D with p value ≤ 0.001. Conclusion : Addition of dexmedetomidine to levobupivacaine for bilateral superficial cervical plexus block considered as an effective and safe block that significantly reduced total postoperative opioid consumption and prolonged time to first postoperative analgesic request with achievement of good quality of analgesia.

Increased plasma cortisol level as acute response to glochidia parasitism

Increased plasma cortisol level as acute response to glochidia parasitism

Natural high ambient temperature-induced respiratory hypocapnia without activation of the hypothalamic-pituitary-adrenal axis in lactating goats.

Activation of breathing, the hypothalamic-pituitary-adrenal (HPA) axis, and plasma antioxidant defense are adaptive mechanisms in lactating dairy goats fed during the summer season. However, an excess of these responses can interfere with the gas exchange. This study aimed to investigate the effect of natural high ambient temperature (HTa) on blood gas parameters and their relation to the HPA axis and antioxidant defense. Six mid-lactating goats were included in this study and were fed in individual pens for 2 weeks. The data on ambient conditions, physiological responses, and blood chemistry were measured for two sampling days (D7 and D14), 1 week apart during the late summer season. On this two-sampling day, the main physiological responses to HTa, including respiration rate (RR), rectal temperature (Tr), blood gas, and blood chemistry, were measured in the morning and afternoon. Goats from both D7 and D14 increased RR and Tr significantly according to morning and afternoon periods. In addition, goats were at the hypocapnia stage during afternoon panting without a change in blood pH and bicarbonate levels. Interestingly, HTa-induced hypocapnia was not accompanied by an increase in plasma cortisol levels. Finally, ΔTa was negatively correlated with changes in glutathione peroxidase activity. The natural HTa (ΔTa; 5-8°C) in this study activated evaporative heat dissipation and was high enough to induce respiratory hypocapnia. Importantly, this ΔTa did not activate the HPA axis but was correlated with a change in antioxidant defense. Therefore, under natural HTa in tropical conditions, respiratory hypocapnia is the first line of physiological response in goats within a specific range of natural ΔTa (5-8°C).

Depression induced by low-frequency repetitive transcranial magnetic stimulation to ventral medial frontal cortex in monkeys

The medial frontal cortex (MFC), especially its ventral part, has long been of great interest with respect to the pathology of mood disorders. A number of human brain imaging studies have demonstrated the abnormalities of this brain region in patients with mood disorders, however, whether it is critically and causally involved in the pathogenesis of such disorders remains to be fully elucidated. In this study, we examined how the suppression of neural activity in the ventral region of the MFC (vMFC) affects the behavioral and physiological states of monkeys by using repetitive transcranial magnetic stimulation (rTMS). By using low-frequency rTMS (LF-rTMS) as an inhibitory intervention, we found that LF-rTMS targeting the vMFC temporarily induced a depression-like state in monkeys, which was characterized by a reduced movement activity level, impaired sociability, and decreased motivation level, as well as increased plasma cortisol level. On the other hand, no such significant changes in behavioral and physiological states were observed when targeting the other MFC regions, dorsal or posterior. We further found that the administration of an antidepressant agent, ketamine, ameliorated the abnormal behavioral and physiological states induced by the LF-rTMS intervention. These findings causally indicate the involvement of the vMFC in the regulation of mood and the validity of the LF-rTMS-induced dysfunction of the vMFC as a nonhuman primate model of depression.

Air sac and gill vasotocin receptor gene expression in the air-breathing catfish Heteropneustes fossilis exposed to water and air deprivation conditions.

Heteropneustes fossilis is a facultative air-breathing freshwater catfish and inhabits ponds, ditches, swamps, marshes and rivers that dry up in summers. It possesses a pair of unique tubular accessory respiratory organ (air sac), which is a modification of the gill chamber and enables it to live in water-air transition zones. In the catfish, three vasotocin (Vt) receptor gene paralogs viz., v1a1, v1a2 and v2a were identified for Vt actions. In the present study, the receptor gene transcripts were localized in the gill and air sac by in situ hybridization, and their expression levels in relation to water and air deprivation conditions were investigated by quantitative RT-PCR. The catfish were exposed to 1h and 2h in gonad inactive (resting) and gonad active (prespawning) phases. The gene paralogs showed overlapping distribution in the respiratory epithelium of primary and secondary lamellae of gills and reduced lamellae of the air sacs. In water deprivation (forced aerial mode of respiration) experiment, v2a expression showed a high fold increase in the air sac, which was unchanged or inhibited in the gill. Both v1a1 and v1a2 expression was significantly upregulated in the air sac but showed varied responses in the gill. The gill v1a1 expression was unchanged in the resting phase and modestly upregulated in the prespawning phase. The gill v1a2 expression was modestly upregulated at 1h in both phases but unchanged at 2h. In the air deprivation experiment (forced aquatic respiration), the v2a expression in the air sac was inhibited except for a mild stimulation at 1h in the prespawning phase. In the gill, the v2a expression was stimulated with a steep upregulation at 2h in the prespawning phase. Both v1a1 and v1a2 expression was significantly high in the gill but only modestly increased or unchanged in the air sac. The expression patterns point to a functional distinction; the V2 type receptor expression was higher in the air sac during forced aerial respiration, and the V1 type receptor expression was highly prominent in the gill during forced aquatic respiration. Water and air deprivation treatments caused a significant increase in plasma cortisol level, and the stimulation was higher in the water deprivation fish in the resting phase but equally prominent in the water and air deprivation groups in the prespawning phase. The results indicate that the changes in the expression patterns of Vt receptor genes may be a sequel to stress (hypoxic, metabolic and osmotic), and both Vt and cortisol may interact to counter the stress responses. This study shows that Vt has a new role in the control of air sac functions.

Performance and welfare status of stable and regrouped beetal does fed at hexagonal vs linear feeder

Performance and welfare status of stable and regrouped Beetal does (N=28) was assessed at hexagonal and linear feeder (n=14 does per group, 7 lactating and 7 non-lactating). Stable groups were compared at hexagonal (DH) and linear (DL) feeders for a period of four weeks. Thereafter, does were regrouped (7 does interchanged, i.e. 4 lactating and 3 non-lactating) at hexagonal (DHM) and linear (DLM) feeder and compared as following four subgroups, i.e. hexagonal retained (DHR), linear-to-hexagonal (DLH), hexagonal-to-linear (DHL) and linear retained (DLR) does (n=7 each). Body weight, milk yield, feed intake, wastage, injuries and blood biochemical parameters were recorded. Blood samples were collected at weekly interval before regrouping and on day 1, 3, 7 and 14 after regrouping. Most of the parameters did not differ between feeder groups before as well as after regrouping. One doe received horn injury after regrouping at hexagonal feeder. Does retained at respective feeder (DHR and DLR) showed increase in plasma cortisol level after regrouping indicative of rise in stress to defend their stable position at feeder or space inside the pen. Results showed that two types of feeder had little influence on performance and welfare of stable does with marginal advantages at linear feeder in regrouped does.

Differential Metabolic and Transcriptional Responses of Gilthead Seabream (Sparus aurata) Administered with Cortisol or Cortisol-BSA.

Cortisol is the main glucocorticoid hormone promoting compensatory metabolic responses of stress in teleosts. This hormone acts through genomic and membrane-initiated actions to exert its functions inside the cell. Experimental approaches, using exogenous cortisol administration, confirm the role of this hormone during short (minutes to hours)- and long-term (days to weeks) responses to stress. The role of membrane-initiated cortisol signaling during long-term responses has been recently explored. In this study, Sparus aurata were intraperitoneally injected with coconut oil alone or coconut oil containing cortisol, cortisol-BSA, or BSA. After 3 days of treatment, plasma, liver, and skeletal muscle were extracted. Plasma cortisol, as well as metabolic indicators in the plasma and tissues collected, and metabolism-related gene expression, were measured. Our results showed that artificially increased plasma cortisol levels in S. aurata enhanced plasma glucose and triacylglycerols values as well as hepatic substrate energy mobilization. Additionally, cortisol stimulated hepatic carbohydrates metabolism, as seen by the increased expression of metabolism-related genes. All of these responses, observed in cortisol-administered fish, were not detected by replicating the same protocol and instead using cortisol-BSA, which exclusively induces membrane-initiated effects. Therefore, we suggest that after three days of cortisol administration, only genomic actions are involved in the metabolic responses in S. aurata.

Adaptogens as anti-stress agents in reducing increased plasma cortisol level during stress

The stress response involves the activation of both the sympathetic-adrenal response and the hypothalamic-pituitary-adrenal axis. During times of increased stress, the adrenal gland is stimulated to produce increased levels of hormones. Cortisol, the main hormone involved in the stress response, is secreted in increased amounts within minutes of a perceived stressor. Cortisol secretion can increase as much as 20-fold and has several important physiological effects. Short-term surges in cortisol levels can suppress inflammation and at the same time suppress immune function. Though inflammation control is important, surges of sustained levels of cortisol are not healthy and ultimately lead to premature aging, degenerative disease, and increased susceptibility to cancer. Studies show that psycho-social stress activates the hypothalamus-pituitary-adrenal axis causing an increase in morning cortisol levels, which correlated to the subjects reports of increased fatigue and anxiety. Although this stress response is important for survival during an acute stressor, prolonged activation of the stress response may lead to adrenal exhaustion in which cortisol levels drop to insufficient levels resulting in fatigue or illness. Many herbs have been shown to impact adrenal function. Adaptogens are plants that produce a non-specific response improving the physiological resistance to stressors. These herbs are often used in the context of adrenal support formulas to balance adrenal hormone levels. It is believed that adaptogenic herbs can increase low levels of adrenal hormone or decrease levels that are elevated. Additionally, these herbs provide balancing activity on many body systems that are impacted by stress, such as the immune response and blood sugar control.In the present study, we have evaluated the efficacy of ethanolic extract of Ocimum sanctum 47mg/kg p.o, Withania somnifera 23 mg/kg p.o and Bacopa monnieri 23 mg/kg p.o on plasma cortisol level in mice subjected to swim endurance test and cold restraint stress. The standard group was administered water-soluble root powder of Panax ginseng 100 mg/kg p.o and the stress control group was administered distilled water orally for 7 days. It was found that mice pretreated with ethanolic extracts of Ocimum sanctum, Withania somnifera and Bacopa monnieri showed a fall in the plasma cortisol level. The standard group also showed a significant decrease in the plasma cortisol level compared to the stress and normal control groups.

Application of Polystyrene Nanofiber in Detection of Anxiety-Related Bio-Marker Cortisol

This work aimed to explore the correlation between plasma cortisol level and the occurrence of anxiety through the polystyrene (PS) nano-fiber solid phase extraction technology. The PS nano-fibers were prepared, and its characterization was performed to detect its adsorption selectivity and blood compatibility. 32 anxiety patients treated in the hospital were recruited as the research subjects, with another 35 mentally healthy people as controls. The Hamilton Anxiety (HAMA) Scale, Symptom checklist-90 (SCL-90) scale, and Eysenck personality questionnaire (EPQ) were used to analyze the anxiety degree, psychological disorder degree, and personality of the two groups. The plasma cortisol level was detected by PS nano-fiber solid phase extraction technology. Finally, the Pearson correlation test was performed to analyze the correlation between the plasma cortisol level and the scores of HAMA scale, SCL-90 scale, and EPQ scale in anxiety patients. It was revealed that the HAMA scale and SCL-90 scale scores of anxiety patients were superior to those of healthy subjects (P &lt; 0.05). The “neuroticism” factor score in EPQ were obviously higher than that of healthy subjects (P &lt; 0.05). The diameter of the prepared PS nano-fiber was within 200~900 nm, with a small specific surface area (BET), pore volume, and pore size, and the cellular structure was noted on the fiber surface. The PS nano-fiber demonstrated relatively good adsorption performance for benzene hydrocarbon compounds and had excellent anti-protein adsorption capacity. It was found that the plasma cortisol level of anxiety patients was higher than that of healthy subjects (P &lt; 0.05), and the plasma cortisol level was positively correlated with HAMA scale, SCL-90 scale, and EPQ scale scores (r = 0.996, 0.993, and 0.971, respectively; P &lt; 0.05). In conclusion, the PS nano-fiber solid phase extraction technology can be applied to identify the plasma cortisol level, which was with a good anti-interference property. An increased plasma cortisol level can be used as an indicator for auxiliary diagnosis of anxiety.

Aflatoxicosis Dysregulates the Physiological Responses to Crowding Densities in the Marine Teleost Gilthead Seabream (Sparus aurata).

Simple SummaryA fungal toxin, aflatoxin B1 (AFB1), undermines growth and stress axes of gilthead seabream (Sparus aurata) with depletion of somatic carbohydrate and lipid reservoirs. The present study assessed the physiological consequences of high stocking density versus low stocking density in seabream juveniles, which had previously been fed with AFB1 supplementation. These stressors are likely to converge by inferring animal welfare and economic profitability in the food animal industry. Interestingly, AFB1 seems to cause physiological and molecular dysfunction in response to overcrowding densities. Our results might be relevant to elucidate a potential risk for fish farming that is often overlooked.Several studies in fish have shown that aflatoxin B1 (AFB1) causes a disparity of species-dependent physiological disorders without compromising survival. We studied the effect of dietary administration of AFB1 (2 mg AFB1 kg−1 diet) in gilthead seabream (Sparus aurata) juveniles in combination with a challenge by stocking density (4 vs. 40 g L−1). The experimental period duration was ten days, and the diet with AFB1 was administered to the fish for 85 days prior to the stocking density challenge. Our results indicated an alteration in the carbohydrate and lipid metabolites mobilization in the AFB1 fed group, which was intensified at high stocking density (HSD). The CT group at HSD increased plasma cortisol levels, as expected, whereas the AFB1-HSD group did not. The star mRNA expression, an enzyme involved in cortisol synthesis in the head kidney, presented a ninefold increase in the AFB1 group at low stocking density (LSD) compared to the CT-LSD group. Adenohypophyseal gh mRNA expression increased in the AFB1-HSD but not in the CT-HSD group. Overall, these results confirmed that chronic AFB1 dietary exposure alters the adequate endocrinological physiological cascade response in S. aurata, compromising the expected stress response to an additional stressor, such as overcrowding.

Prenatal Exposure to High Cortisol Induces ADHD-like Behaviors with Delay in Spatial Cognitive Functions during the Post-weaning Period in Rats.

High levels of cortisol in blood are frequently observed in patients with major depressive disorders and increased cortisol level induces depressivelike symptoms in animal models. However, it is still unclear whether maternal cortisol level during pregnancy is a critical factor resulting in neuropsychiatric disorders in offspring. In this study, we increased cortisol level in rats by repetitively injecting corticosterone subcutaneously (Corti. Mom, 20 mg/kg/day) during pregnancy and evaluated the behavioral patterns of their pups (Corti.Pups) via forced swimming (FS), open field (OF), elevated plus maze (EPM) and Morris water maze (MWM) tests during the immediate post-weaning period (postnatal day 21 to 25). In results, corticosterone significantly increased plasma cortisol levels in both Corti.Moms and Corti.Pups. Unlike depressive animal models, Corti.Pups showed higher hyperactive behaviors in the FS and OF tests than normal pups (Nor.Pups) born from rats (Nor.Moms) treated with saline. Furthermore, Corti.Pups spent more time and traveled longer distance in the open arms of EPM test, exhibiting higher extremity. These patterns were consistent with behavioral symptoms observed in animal models of attention deficit hyperactivity disorder (ADHD), which is characterized by hyperactivity, impulsivity, and inattention. Additionally, Corti.Pups swam longer and farther to escape in MWM test, showing cognitive declines associated with attention deficit. Our findings provide evidence that maternal cortisol level during pregnancy may affect the neuroendocrine regulation and the brain development of offspring, resulting in heterogeneous developmental brain disorders such as ADHD.

RF9 Rescues Cortisol-Induced Repression of Testosterone Levels in Adult Male Macaques.

Cortisol inhibits hypothalamic-pituitary-gonadal (HPG) axis whereas RF9, a potent agonist of kisspeptin receptor (GPR54) activates HPG-axis during fasting-induced stress and under normal physiological conditions. However, the effect of RF9 on the cortisol-induced repressed HPG-axis is not studied yet. This study investigated whether exogenous cortisol-induced repression of the HPG-axis can be rescued by RF9. Six intact adult male rhesus monkeys (Macaca mulatta) habituated to chair-restraint were administered hydrocortisone sodium succinate at a rate of 20 mg/kg of body weight (BW) per day for 12 days. Single blood sample was taken by venipuncture from each animal on alternate days for hormones analyses. On experimental day 12, hydrocortisone treated monkeys received a single intravenous bolus of RF9 (n = 3) and vehicle (n = 3). The animals were bled for a period of 4 h at 60 min intervals from an indwelling cannula in the saphenous vein. RF9 was administered intravenously at the dose of 0.1 mg/kg BW immediately after taking 0 min sample. Plasma cortisol and testosterone concentrations were measured by using specific enzyme immunoassays. Hydrocortisone treatment increased plasma cortisol levels (P ≤ 0.0001) and decreased plasma testosterone (P ≤ 0.0127) levels. Interestingly, compared to vehicle, RF9 treatment significantly increased plasma testosterone levels at 120 min (P ≤ 0.0037), 180 min (P ≤ 0.0016), and 240 min (P ≤ 0.0001) intervals in the hydrocortisone treated monkeys. From these results, we concluded that RF9 administration relieves the suppressed HPG-axis in term of plasma testosterone levels in the cortisol treated monkeys.