Stress-related Physiological Responses Research Articles

Influence of Histology and Histomorphometry of Thigh Muscles on Thermal Stress-Related Physiological and Plasma Hormonal Responses in Three Broiler Strains

Influence of Histology and Histomorphometry of Thigh Muscles on Thermal Stress-Related Physiological and Plasma Hormonal Responses in Three Broiler Strains

Stress-related physiological responses and ultrastructural changes in Hypoxis hemerocallidea leaves exposed to cadmium and aluminium

Hypoxis hemerocallidea is a medicinal plant containing hypoxoside (a pharmacologically active phytosterol diglucoside). This study evaluated the elemental composition in leaves of H. hemerocallidea treated with cadmium (Cd) and aluminium (Al) using scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDX). The impact of Cd and Al on photosynthetic pigments and performance, antioxidant activities and ultrastructure were also assessed. Corms of H. hemerocallidea were micropropagated, rooted and then exposed to varying concentrations of Cd, Al, and Cd + Al for six weeks. The SEM/EDX analysis indicated a two-fold increase in carbon content across all treated plants compared to the control. No/little Cd was detected in the leaves compared to a progressive increase in Al concentration with increasing Al treatment levels. This indicted that Al is more readily translocated to the shoots compared to Cd. Plants treated with Cd exhibited a significant decrease in total chlorophyll content accompanied by reduced photosynthetic performance and lower relative electron transport rates. Cd and Al exposure led to higher carotenoid, superoxide dismutase and malondialdehyde levels, indicating oxidative stress. Cd-treated plants displayed increased amylase activity and decreased carbohydrates content. Ultrastructural alterations occurred with exposure to Cd and Al, including abnormal swelling or disintegration of chloroplasts and thylakoid degeneration. An increase in starch grains and a decrease in plastoglobuli were also noted. In conclusion, this investigation provides evidence that both Cd and higher concentrations of Al exert detrimental effects on the ultrastructure, metabolism and photosynthetic performance of H. hemerocallidea, contributing to reduced growth and biological activity when stressed.

Thermal stress-related physiological, behavioral, and serum biochemical responses in indigenous pigs adapted to Eastern Himalayan region.

The current study was carried out to investigate the effect of micro-environmental variations on physiological, behavioral, and serum biochemical parameters of indigenous (Niang Megha), Hampshire, and crossbred (75% Hampshire X 25% Niang Megha). Rectal temperature (TR), skin surface temperature (TSS), respiration rate (RR), and heart rate (HR) were recorded at 0,900 and 1,600 h weekly once for 2 months for each season in grower pigs of each genotype. CCTV video cameras were utilized to observe the behavioral changes. Five milliliters of blood samples was collected to estimate different biochemical parameters. Season affected (p < 0.05) all physiological parameters which generally increased during summer except TR and RR of indigenous pig. TR, TSS, RR, and HR were significantly (p < 0.05) higher for Hampshire than for indigenous and crossbred in the summer season. The frequency and behavioral activities to heat loss or to conserve heat such as shivering and wallowing were lower except for physical activity that was higher at all times in indigenous pigs. Seasonal variations influenced metabolic activity and serum activity of alkaline phosphatase (ALP) and alanine transaminase (ALT), which rose in summer in all genotypes. Serum ALP and thyroxine (T4) were significantly (p < 0.05) higher for indigenous pig in both the seasons. The insulin level was significantly (p < 0.05) higher in indigenous pigs with no significant difference between Hampshire and crossbred in summer whereas there was significant difference among the genotypes in winter. However, superoxide dismutase (SOD) showed no significant difference in the study. Indigenous pigs had the lowest serum cortisol concentrations, whereas Hampshire had the highest. The current study's findings on several parameters of three different genotypes suggest that indigenous pigs in this region are more adaptable to the region's changing climatic conditions.

Positive welfare effects of physical enrichments from the nature-, functions- and feeling- based approaches in farmed rainbow trout (Oncorhynchus mykiss)

The present study aimed to investigate whether environmental enrichment had significant effects on rainbow trout's welfare through nature-, functions- and feeling-based approaches. Fish group behavior was analyzed during the rearing phase, as well as growth performance and health status. We assessed individual's emotional reactivity through a novel-tank test by measuring fear-related behaviors and stress-related physiological responses. Fish boldness and neophobia were then evaluated towards a novel object. We showed that more complex environments decreased aggression levels and improved growth, without impacting fish immune status. Enriched fish were also found less fearful when isolated in a novel tank and bolder when facing a novel object. We concluded that complexifying the environment through the addition of physical structures which stimulate and encourage fish to explore promotes rainbow trout's welfare in farming conditions, according to the three different welfare approaches.

304 Effects of Supplementing Phix-up® on Productive, Physiological, and Rumen Responses of Feedlot Cattle Consuming a Corn-based Finishing Diet

Abstract This experiment (d -14 to 118) compared rumen pH, productive, and physiological responses in finishing cattle supplemented or not with a rumen-buffering agent (pHix-up®; Timab, Dinard, France). Angus-influenced yearling cattle (58 heifers and 62 steers) were ranked by sex and body weight (BW) and allocated to 4 groups of 30 animals each (d -14). Groups were housed in 1 of 4 drylot pens equipped with GrowSafe automated feeding systems, and assigned to receive a corn-based diet containing monensin, and with the inclusion of pHix-up® at 0.00% (control) 0.25%, 0.50%, or 0.75% (d 0 to 118). Cattle BW was recorded twice monthly (d -14 to 118), and blood samples were collected on d 0, 28, 56, 84 and 112. Hair samples from the tail-switch were collected on d 0, 56 and 112. Cattle were slaughtered on d 119. Eight rumen-cannulated steers were also assigned to this experiment (d 42 to 98), with 2 steers housed with each group in a replicated 4 × 4 Latin Square design (4 periods of 14 d). Rumen pH was measured on d 7 and 14 of each period at 0800h, 1200h, 1600h and 2000h. No treatment effects were noted (P ≥ 0.13) for cattle BW gain, feed intake, and feed efficiency. Inclusion of pHix-up® linearly increased (P &amp;lt; 0.01) plasma Mg concentrations and tended to linearly decrease (P = 0.09) plasma haptoglobin concentrations. Cattle receiving pHix-up® had greater (P &amp;lt; 0.01) mean plasma cortisol concentrations compared with non-supplemented cattle. Hair cortisol concentration linearly decreased (P &amp;lt; 0.01) as pHix-up® inclusion increased on d 112 (treatment × day interaction; P = 0.02). In rumen-cannulated steers, pHix-up® inclusion linearly increased (P = 0.03) mean rumen pH. Collectively, pHix-up® supplementation improved rumen pH and modulated stress-related physiological responses in finishing cattle, but without improving their productive responses.

Measuring Faecal Glucocorticoid Metabolite Concentrations as an Indicator of Stress in Blue Wildebeest (Connochaetes taurinus)

In South Africa, blue wildebeest (Connochaetes taurinus) are routinely captured for relocation purposes. To monitor the stress caused by this practise, a non-invasive method assessing adrenocortical function as a measure of stress would minimize disturbance during sample collection. In our study, an adrenocorticotropic hormone challenge, and a mass-capture event were used to examine the suitability of five enzyme immunoassays (EIAs) for monitoring stress-related physiological responses using faeces as a sample matrix. The tested 11-oxoaetiocholanolone I EIA performed best, showing a 2126% increase above baseline after 22 h for a male, and a 474% increase for a female 23 h post-ACTH injection. Baseline faecal glucocorticoid metabolite (fGCM) concentrations did not differ between animals captured on either day 1 or day 2 of the capture event, indicating that the frequent presence of a helicopter during the two days did not influence fGCM concentrations. However, during capture-related restraint for up to 10 h, an overall 1.5-fold elevation in (fGCM) concentrations was found. Storage of faeces at ambient temperature post-defecation indicated a fair stability of fGCMs for up to 8 h. The ability to reliably assess adrenocortical function provides a solid basis to examine endocrine responses to putative stressful circumstances in blue wildebeest.

Stress-related physiological and histological responses of tambaqui (Colossoma macropomum) to transportation in water with tea tree and clove essential oil anesthetics

The present study evaluated the effects of the combination of tea tree and clove oils in comparison with salt added to water on the stress indicators in tambaqui subjected to two transportation experiments: one lasting 15 h and another 36 h. The fish were divided into two treatment groups and then transported in plastic bags (195 g L−1; 20 replicates per treatment) containing previously prepared water. In the group with 2 oils (MEUG), the fish were transported in water added with 10.4 mg L−1 of anesthetic solution of tea tree and clove oils while in salt (SALT) at 0.8% was added. The basal group comprised fish that were not subjected to transportation. The efficacy of these phytotherapics was verified by analyzing biochemical, hematological and histological indicators after transportation and 96 h of recovery. The levels of cortisol, glucose and plasma lactate increased after transportation in comparison with the basal ones. The glycemic values of the MEUG treatment were inferior to the SALT treatment, regardless transportation time. The same occurred for the lactate, only in the 15-h experiment. The hepatic glycogen levels were higher in the MEUG treatment. No alterations were observed in the ions (sodium, chloride, potassium) regardless treatment and transportation time. The hemoglobin concentration increased in the SALT treatment after transportations for 15 h and 36 h. The gills did not undergo deleterious morphophysiological alterations. Except for the hepatic glycogen in the SALT treatment, all parameters were similar to the basal ones after recovery for 96 h. The indicators showed primary and secondary responses to stress, with more favorable results for the 15 h and 36 h transportations using the combined essential oils of tea tree and clove at 10.4 mg L−1 for sedation.

Validating a non-invasive technique for monitoring physiological stress in the samango monkey.

The non-invasive monitoring of physiological stress can provide conservation and wildlife managers with an invaluable tool for assessing animal welfare and psychological health of captive and free-ranging populations. A significant decrease in free-ranging primate populations globally and an increase in captive-housed primates have led to a need to monitor the stress and general welfare of these animals. We examined the suitability of three enzyme immunoassays (EIAs) for monitoring stress-related physiological responses in the samango monkey, Cercopithecus albogularis erythrarchus. We conducted an adrenocorticotropic hormone (ACTH) challenge on a male and female at the National Zoological Garden, Pretoria, South Africa. Individual faecal samples were collected 8 days pre- and post-ACTH administration and subsequently analysed for faecal glucocorticoid metabolite (fGCM) concentrations. During the study, biological stressors occurred for both the male and female. Two of the three EIAs tested (11-oxoetiocholanolone I and II) were able to reliably monitor fGCM alterations throughout the study period in both sexes. The 11-oxoetiocholanolone I EIA, however, had the lowest mean deviation from the calculated baseline value and was thus chosen as the preferred assay. Both the physiological activation of the stress response and the biological response to a stressor could be monitored with the chosen assay. The successful establishment of a reliable, non-invasive method for monitoring adrenocortical activity in C. albogularis erythrarchus will now allow conservationists, scientific researchers and wildlife managers to evaluate the level of stress experienced, and general welfare, by animals in captivity as well as free-ranging populations.

Engraulis encrasicolus larvae from two different environmental spawning areas of the Central Mediterranean Sea: first data on amino acid profiles and biochemical evaluations

Early life stages of marine fish populations may be strongly affected by environmental factors. Changes in the physical environment or the availability of food resources could lead to stress-related physiological responses affecting larval fitness, growth and survival. In the present study, we determined, for the first time, amino acid composition (AAC), lipid, and carbohydrate content, as well as alkaline phosphatase and peroxidase activities in larvae from the European anchovy Engraulis encrasicolus. Fishes were caught in two different spawning areas of the Strait of Sicily, characterized by different environmental conditions, including a coastal upwelling with a lower temperature (Adventure Bank; 20.22 ± 0.38°C) and a thermohaline front with a higher temperature (Maltese Bank 23.10 ± 0.25°C). The results showed that the two groups of larvae, in their early life, had similar nutritional status. However, compared with the samples from the Maltese Bank, the specimens collected in the Adventure Bank area exhibited higher alkaline phosphatase activity, lower concentrations of aspartate plus asparagine, threonine, and arginine but a higher concentration of leucine, highlighting different patterns of amino acid metabolism. Collectively, these results indicated that AAC analysis could represent an additional valid tool to evaluate the link between physiological responses and environmental conditions at early life stages.

The Role of Anthropogenic Elements in the Environment for Affective States and Cortisol Concentration in Mountain Hiking-A Crossover Trial.

Green exercise might have positive effects on health and affective states. Little is known about the ideal characteristics of the natural environment, where exercise is conducted in. Thus, the primary aim of the present study was to investigate the effects of anthropogenic elements on acute stress-related physiological responses and affective states in green exercise. Using a crossover field study design, 52 healthy participants were exposed to two different mountain hiking conditions: An environment with less anthropogenic elements and an environment with more anthropogenic elements. Pre and post conditions, affective states and salivary cortisol concentration were measured. Repeated measures ANOVAs were used to analyze if pre-post changes differed between the conditions. Pre-post changes in affective states and salivary cortisol concentration did not significantly differ, partial η² < 0.06. Positive affective states showed significantly higher values post compared to pre-condition, partial η² > 0.13. The present results indicate that anthropogenic elements have a minor role in the influence on affective states and salivary cortisol concentration during mountain hiking. It is concluded that a single bout of mountain hiking independent of anthropogenic elements in the environment is effective in influencing affective states positively.

Metabolomics and its physiological regulation process reveal the salt-tolerant mechanism in Glycine soja seedling roots

Wild soybean (Glycine soja) is an excellent germplasm resource and has strong resistance and wide adaptability to different environments. Hence, the physiology and metabolomics characteristics of wild soybean under different types of salt stress were determined to improve understanding of salt-tolerant mechanisms of wild soybean in the field. Two types of wild soybean seedlings were exposed to two different types of salt stress for 14 d. The photosynthesis of wild soybean seedling extracts were analyzed using metabolomics based on gas chromatography-mass spectrometry. The wild soybean root extracts used metabolomics to quantify the metabolic changes and ion contents. The assimilative function of photosynthesis in salt-tolerant wild soybean was less inhibited than in common wild soybean, and it regulated accumulation of toxic ions and maintained the accumulation of K+ and Mg2+ to alleviate salt stress. Moreover, in resisting salt stress the salt-tolerant wild soybean has showed improved amino acid and carbohydrate and polyol metabolisms under neutral-salt stress and organic acid, amino acid and tricarboxylic acid metabolisms under alkali-salt stress. Our results provide valuable insights into the response of salt-tolerant wild soybean to two types of salt stress by linking stress-related physiological responses to changes in metabolites.

A Randomized Crossover Trial on Acute Stress-Related Physiological Responses to Mountain Hiking.

Green exercise, defined as physical activity in natural environments, might have positive effects on stress-related physiological measures. Little is known about the acute effects of green exercise bouts lasting longer than 60 min. Therefore, the aim of the present study was to analyze the acute effects of a three-hour green exercise intervention (mountain hiking) on stress-related physiological responses. Using a randomized crossover design, 42 healthy participants were exposed to three different conditions in a field-based experiment: outdoor mountain hiking, indoor treadmill walking, and sedentary control condition (three hours each). At baseline and at follow-up (five minutes after the condition), stress-related physiological responses (salivary cortisol, blood pressure, and heart rate variability) were measured. Salivary cortisol decreased in all conditions, but showed a larger decrease after both mountain hiking and treadmill walking compared to the sedentary control situation (partial η2 = 0.10). No differences were found between mountain hiking and treadmill walking in salivary cortisol. In heart rate variability and blood pressure, changes from baseline to follow-up did not significantly differ between the three conditions. The results indicate that three hours of hiking indoors or outdoors elicits positive effects on salivary cortisol concentration. Environmental effects seem to play a minor role in salivary cortisol, blood pressure, and heart rate variability.

Adaptation of exercise-induced stress in well-trained healthy young men.

What is the central question of this study? Exercise is known to induce stress-related physiological responses, such as changes in intestinal barrier function. Our aim was to determine the test-retest repeatability of these responses in well-trained individuals. What is the main finding and its importance? Responses to strenuous exercise, as indicated by stress-related markers such as intestinal integrity markers and myokines, showed high test-retest variation. Even in well-trained young men an adapted response is seen after a single repetition after 1 week. This finding has implications for the design of studies aimed at evaluating physiological responses to exercise. Strenuous exercise induces different stress-related physiological changes, potentially including changes in intestinal barrier function. In the Protégé Study (ISRCTN14236739; www.isrctn.com), we determined the test-retest repeatability in responses to exercise in well-trained individuals. Eleven well-trained men (27±4 years old) completed an exercise protocol that consisted of intensive cycling intervals, followed by an overnight fast and an additional 90min cycling phase at 50% of maximal workload the next morning. The day before (rest), and immediately after the exercise protocol (exercise) a lactulose and rhamnose solution was ingested. Markers of energy metabolism, lactulose-to-rhamnose ratio, several cytokines and potential stress-related markers were measured at rest and during exercise. In addition, untargeted urine metabolite profiles were obtained. The complete procedure (Test) was repeated 1week later (Retest) to assess repeatability. Metabolic effect parameters with regard to energy metabolism and urine metabolomics were similar for both the Test and Retest period, underlining comparable exercise load. Following exercise, intestinal permeability (1h plasma lactulose-to-rhamnose ratio) and the serum interleukin-6, interleukin-10, fibroblast growth factor-21 and muscle creatine kinase concentrations were significantly increased compared with rest only during the first test and not when the test was repeated. Responses to strenuous exercise in well-trained young men, as indicated by intestinal markers and myokines, show adaptation in Test-Retest outcome. This might be attributable to a carry-over effect of the defense mechanisms triggered during the Test. This finding has implications for the design of studies aimed at evaluating physiological responses to exercise.

MiR-375 Mediates CRH Signaling Pathway in Inhibiting E2 Synthesis in Porcine Ovary.

The corticotropin-releasing hormone (CRH) signaling system is involved in numbers of stress-related physiological and pathological responses，including its inhibiting effects on estradiol (E2) synthesis and follicular development in the ovary. In addition, there are reports that microRNAs (miRNAs) can control the function of animal reproductive system. The aim of present study was to investigate the functions of miR-375 and the relationship between miR-375 and CRH signaling molecules in the porcine ovary. First, our common PCR results show that miR-375 and the CRH receptor 1 (CRHR1) are expressed in porcine ovary, whereas CRH receptor 2 (CRHR2) is not detected. We further have located the cell types of miR-375 and CRHR1 by in situ hybridization (ISH), and the results show that miR-375 is located only in the granulosa cells, whereas CRHR1 is positive in all of granulosa cells and oocytes, inferring that miR-375 and CRHR1 are co-localized in granulosa cells. Second, we show that overexpression of miR-375 in cultured granulosa cells suppresses the E2 production, while miR-375 knockdown demonstrates the opposite result. Besides, our in vitro results demonstrate that miR-375 mediates the signaling pathway of CRH inhibiting E2 synthesis. Finally, our data show that the action of miR-375 is accomplished by directly binding to the 3'UTR of specificity protein1 (SP1) mRNA to decrease the SP1 protein level. Thus, we conclude that miR-375 is a key factor in regulating E2 synthesis by mediating the CRH signaling pathway.

Non-invasive measurement of adrenocortical activity in a myrmecophageous mammal, the bat-eared fox

Measuring physiological stress reactions through the quantification of plasma cortisol often involves physical restraint, which acts as a stressor itself. Here, we present the validation of a non-invasive method for assessing adrenocortical activity as an indicator of stress in the bat-eared fox (Otocyon megalotis). By conducting an adrenocorticotropic hormone (ACTH) challenge, we examined the suitability of three enzyme immunoassays (EIAs) detecting 11,17 dioxoandrostanes (11,17-DOA) as well as faecal glucocorticoid metabolites (fGCM) with a 5β-3α-ol-11-one (3α,11oxo-CM), or 11,17,21-trihydroxy-4-ene-20-one structure (cortisol), respectively, for monitoring stress-related physiological responses in male and female bat-eared foxes. Our results suggest that the cortisol EIA seems most suitable for measuring fGCMs in this myrmecophageous mammal. Using the cortisol EIA, we compared fGCM concentrations of three populations of foxes. Only one population experienced a sudden change in social environment and the assay appeared to effectively detect the expected resulting increase in stress hormone levels. Therefore, the identified EIA is effective at detecting intraspecific variation in fGCM levels and hence is a useful tool to evaluate physiological stress responses in this species.

Physiological Responses and Comparison of Protein Changes in the Leaves of Two Wheat (Triticum aestivumL.) Genotypes by 2-D Electrophoresis Under NaCl Salinity Stress

A pot experiment was conducted to investigate salinity stress related physiological responses and comparison of protein changes in the leaves of two wheat genotypes at CRI (Crown Root Initiation) and booting stages. Physiological approach is a preliminary marker to know the effect of salinity amelioration. MSI (Membrane Stability Index) and RWC (Relative Water Content) of wheat leaves were reduced in salinity susceptible genotype GW-496 than in salinity tolerant genotype GW-173 at both the stages. The results also revealed that MSI and RWC were recorded highest at control condition and lowest @160 mM NaCl treatment at booting stage. In proteomics investigation, gel analysis of the resulting protein patterns revealed genotype specific and salt stress responsive protein expression. Total 419 of protein spots were found under match Id in control as well as in treated tolerant and susceptible genotypes at CRI and booting stage. More number of protein expressions was noticed in the tolerant genotype than in the susceptible genotype at both the stages. The change in physiological parameters varied with genotypes and the crop growth stages. Proteomics results indicate that tolerance to salt stress is associated with changes of protein levels in wheat genotypes. In particular, comparative proteomic investigations of plants before and after specific or interactive stresses allow us to obtain information on how defensive mechanisms are adopted from plants which might be helpful in the development of future strategies against salinity stress.

Impact of Childhood Maltreatment on the Recognition of Facial Expressions of Emotions.

The development of the explicit recognition of facial expressions of emotions can be affected by childhood maltreatment experiences. A previous study demonstrated the existence of an explicit recognition bias for angry facial expressions among a population of adolescent Sierra Leonean street-boys exposed to high levels of maltreatment. In the present study, the recognition bias for angry facial expressions was investigated in a younger population of street-children and age-matched controls. Participants performed a forced-choice facial expressions recognition task. Recognition bias was measured as participants’ tendency to over-attribute anger label to other negative facial expressions. Participants’ heart rate was assessed and related to their behavioral performance, as index of their stress-related physiological responses. Results demonstrated the presence of a recognition bias for angry facial expressions among street-children, also pinpointing a similar, although significantly less pronounced, tendency among controls. Participants’ performance was controlled for age, cognitive and educational levels and for naming skills. None of these variables influenced the recognition bias for angry facial expressions. Differently, a significant effect of heart rate on participants’ tendency to use anger label was evidenced. Taken together, these results suggest that childhood exposure to maltreatment experiences amplifies children’s “pre-existing bias” for anger labeling in forced-choice emotion recognition task. Moreover, they strengthen the thesis according to which the recognition bias for angry facial expressions is a manifestation of a functional adaptive mechanism that tunes victim’s perceptive and attentive focus on salient environmental social stimuli.

Differential deployment of parthenolide and phenylpropanoids in feverfew plants subjected to divalent heavy metals and trans-cinnamic acid

Accumulation of defense metabolites is an adaptive response to heavy metals in plants. However, deployment of multiple classes of defense metabolites under cadmium (Cd) and copper (Cu) toxicity is not understood. Here, the responses of parthenolide and phenylpropanoids were examined. Quantification of parthenolide and phenylpropanoids, and the expression of parthenolide biosynthesis genes were performed in feverfew leaves. Photosynthetic and physiological analysis of feverfew seedling treated with Cd and Cu were used to confirm the relationship between concentration of heavy metals and secondary metabolites accumulation. In addition, we examined the role of trans-Cinnamic acid (CA) as a phenylalanine ammonia-lyase (PAL) inhibitor alone or together with different Cd and Cu concentrations on plant growth and metabolites accumulation. Application of different Cu concentrations alone was more phytotoxic than respective Cd concentrations alone in terms of plant growth, photosynthesis, and oxidative status; however, addition of CA improved these attributes compared with their respective treatments alone. The results also revealed the repressing parthenolide biosynthesis versus phenylpropanoids when plants treated with heavy metals, whereas CA treatment showed the inverse effect. This study provides valuable information into the response of feverfew plants to Cd or Cu alone or together with a PAL inhibitor by linking stress-related physiological responses to changes in metabolites.

Evaluation of bathing with and without acute bouts of exercise at salivary levels of α-amylase and IgA in men

Introduction: Evaluating how bathing influences various aspects of physiological responses is necessary to understand comprehensive mental and physical stress-related responses in humans. Although previous studies have argued effects of bathing on stress-related physiological responses, such as exercise-induced immunosuppression, salivary responses to bathing after exercise still remain unclear. The purpose of this study was to determine the effects of bathing with and without acute bouts of exercise on salivary levels of -amylase and IgA in men. Methods: Twelve recreationally active male collegiate students [age: 20.5±1.1 year; height: 169.6±6.8 cm; body mass: 63.1±6.9 kg; BMI: 22.0±2.7 kg/m2; body fat: 15.4±4.7% (mean± SD)] served as the subjects. The protocols consisted of two trials, which are: either (i) exercise (5min warm-up, 30 times of sit-ups, push-ups, and back-extensions, followed by 8 times of 40m sprint with 5min cool-down) plus bathing (E +B) or (ii) only bathing (B). Two experimental trials were performed on two different occasions separated by seven days under similar environmental conditions. Unstimulated saliva samples were collected within 10minutes before (Pre) and after (Post) each trial for analysis of salivary -amylase (a marker for a sensitive biomarker for stress-related changes in the body which reflect the sympathetic nervous system activity) and IgA (a marker for the incidence of URTI) and levels. Salivary -amylase and IgA levels were determined by an enzymatic assay and turbidimetric immunoassay, respectively. Results: In light of salivary -amylase activity, two-way analysis of variance (ANOVA) showed no significant main effects of time and intervention or interactions (Pre =181.6±157.9, Post = 228.7± 110.2 for E +B; Pre =246.3±205.2, Post = 198.7±125.5U/mL for B) before and after each trial. Furthermore, ANOVA for salivary IgA concentration demonstrated similar patterns (no significant maineffects of timeand interventionor interactions; Pre =8.2±2.5, Post = 10.6±3.5 for E +B; Pre =7.6±3.3, Post = 9.4±4.4mg/dL for B). Discussion: Previous studies have reported the effects of bathing on the recovery from fatigue following exercise. However, a paucity of data has been available concerning salivary responses to bathing after exercise-induced stress. The findings of the present study indicate that there appears to be similar salivary responses regardless of having short-duration exercise intervention, which implies thatbathing followingacuteboutsof exercise seems tohave had potential recovery from fatigue.

Metabolic response of maize (Zea mays L.) plants to combined drought and salt stress

Maize is exposed to the combined stresses of water deficiency and soil salinity within its natural habitat, particularly in irrigated and dry land agricultural areas. Hence, the effect of these combined stresses on the metabolic response of maize plants was determined to improve understanding of stress tolerance mechanisms of maize in the field. Maize plants were either singly or simultaneously exposed to soil water deficiency and high salinity for 7 d. Physiological characteristics were analyzed and metabolic changes were quantified by conducting 1H NMR-based analysis of polar and non-polar fractions of maize leaf extracts. The response of maize plants to the combined stresses was distinct from that of plants subjected to either drought stress or salt stress alone at both the metabolic and physiological level. Maize plants showed a new pattern of metabolic response to the combined stresses. Some metabolites specifically responded to combined stresses and differed from those caused by each stress applied individually. The global metabolic response of maize to the combined stresses was related to the physiological processes. Our results provide valuable insights into the response of maize to combined drought and salt stress by linking stress-related physiological responses to changes in metabolites.