Effects of thermal stress on the expression of glucocorticoid receptor complex linked genes in Senegalese sole (Solea senegalensis): Acute and adaptive stress responses.

The present study examined the short and mid-term effects of a rise in temperature from 18°C to 24°C on the expression of genes related to the stress response regulation in juveniles of Senegalese sole, Solea senegalensis. The animals were exposed to a temperature increase of 6°C, after 1month of acclimation at 18°C. After this process, samples of different tissues were collected from a total of 96 fish at four sampling points: 1h, 24h, 3days and 1week. The transcript levels of a set of genes involved in the stress response such as glucocorticoid receptors 1 and 2, corticotrophin-releasing factor, corticotrophin-releasing factor binding proteins, proopiomelanocortin A and B, and cellular stress defense (heat shock protein 70, 90AA and 90AB) were quantified at these sampling points. Additionally, blood samples were also taken to measure the circulating plasma cortisol concentration. Thermal stress induced by increasing temperature prompted an elevation of plasma cortisol levels in juvenile Senegalese sole after 1h as a short-term response, and a consecutive increase after one week, as a mid-term response. Senegalese sole seemed to respond positively in terms of adaptive mechanisms, with a rapid over-expression of grs and hsps in liver and brain, significantly higher after one hour post stress, denoting the fast and acute response of those tissues to a rapid change on temperature. The ratio hsp90/gr also increased 24h after thermal shock, ratio proposed to be an adaptive mechanism to prevent proteosomal degradation of GR. As a mid-term response, the elevation of brain crfbp gene expression one week after thermal shock could be an adaptive mechanism of negative feedback on HPI axis. Taken together, these data suggested an initial up-regulation of the glucocorticoid receptor complex linked genes in response to a temperature increase in Senegalese sole, with heat shock protein 90 potentially being a regulatory factor for the glucocorticoid receptor in the presence of cortisol.

Effects of a physical activity program on the urinary collagen crosslinks in pre- and postmenopausal women.

BACKGROUND: This study analyzes the effects of physical exercise on urinary collagen crosslinks, pyridinoline (PYD) and deoxipyridinoline (DPD), in women. METHODS: Thirty premenopausal (PRE) and 40 postmenopausal (PST) women took part in a six month randomized controlled trial of moderate physical exercise. Moreover, skinfold thickness, muscle strength and flexibility were evaluated. RESULTS: Basal values of urinary PYD and DPD were higher in postmenopausal women versus premenopausal women (P<0.01). Physical exercise increased in both groups urinary PYD levels (P<0.05) and urinary DPD levels in postmenopausal women (P<0.05). After the exercise program, no changes were observed in the levels of urinary DPD in premenopausal women. Significant improvements in flexibility, muscle strength and decrease in skinfolds thickness were observed in the exercise group. No changes were observed in non-exercise group. CONCLUSIONS: In conclusion, the physical activity program produced beneficial effects on muscle strength and flexibility and changes in the musculoskeletal system. Also, the physical activity program led to a non-pathological increase in the urinary elimination of bone reabsorption and collagen metabolism biomarkers.

Modulation of the Expression of Components of the Stress Response by Dietary Arachidonic Acid in European Sea Bass (Dicentrarchus labrax) Larvae.

This study reports for the first time on European sea bass, Dicentrarchus labrax (L.), larvae, the effect of different levels of dietary arachidonic acid (ARA; 20:4n-6) on the expression of genes related to the fish stress response. Copies of mRNA from genes related to steroidogenesis [StAR (steroidogenic acute regulatory protein), c-Fos, and CYP11ß (11ß-hydroxylase gene)], glucocorticoid receptor complex [GR (glucocorticoid receptor) and HSP (heat shock proteins) 70 and 90) and antioxidative stress (catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase] were quantified. Eighteen day-old larvae were fed for 14 days with three experimental diets with increasing levels of ARA (0.3, 0.6 and 1.2% d.w.) and similar levels of docosahexaenoic (22:6n-3) and eicosapentaenoic (20:5n-3) acids (5 and 3%, respectively). The quantification of stress-related genes transcripts was conducted by One-Step TaqMan real time RT-PCR with the standard curve method (absolute quantification). Increase dietary levels of ARA induced a significantly (p < 0.05) down-regulation of genes related to cortisol synthesis, such as StAR and CYP11ß and up-regulated genes related to glucocorticoid receptor complex, such as HSP70 and GR. No effects were observed on antioxidant enzymes gene expression. These results revealed the regulatory role of dietary ARA on the expression of stress-related genes in European sea bass larvae.

Comparative cytochrome p450 in vitro inhibition by atypical antipsychotic drugs.

The goal of this study was to assess in human liver microsomes the inhibitory capacity of commonly used antipsychotics on the most prominent CYP450 drug metabolizing enzymes (CYP1A2, CYP2C9, CYP2D6, and CYP3A). Chlorpromazine was the only antipsychotic that inhibited CYP1A2 activity (IC50 = 9.5 µ M), whilst levomepromazine, chlorpromazine, and thioridazine significantly decreased CYP2D6-mediated formation of 1'-hydroxybufuralol (IC50 range, 3.5-25.5 µ M). Olanzapine inhibited CYP3A-catalyzed production of 1', and 4'-hydroxymidazolam (IC50 = 14.65 and 42.20 µ M, resp.). In contrast, risperidone (IC50 = 20.7 µ M) and levomepromazine (IC50 = 30 µ M) showed selectivity towards the inhibition of midazolam 1'-hydroxylation reaction, and haloperidol did so towards 4'-hydroxylation (IC50 of 2.76 µ M). Thioridazine displayed a Ki of 1.75 µ M and an inhibitory potency of 1.57 on CYP2D6, suggesting a potential to induce in vivo interactions. However, with this exception, and given the observed Ki values, the potential of the assayed antipsychotics to produce clinically significant inhibitions of CYP450 isoforms in vivo seems limited.

Total substitution of fish oil by vegetable oils in Senegalese sole (Solea senegalensis) diets: effects on fish performance, biochemical composition, and expression of some glucocorticoid receptor-related genes.

To study the substitution of fish oil by vegetable oils in fish diets, juveniles Senegalese sole (Solea senegalensis) were fed diets (56 % crude protein, 12 % crude lipid) containing either linseed (100LO) or soybean (100SO) oils in comparison with a 100 % fish oil-based diet (100FO) for 90 days. Samples of muscle, liver, and intestine were collected for biochemical analysis and for glucocorticoid receptor-related genes, including GR1 and GR2, and the associated heat shock proteins HSP70, HSP90AA, and HSP90AB. Besides, basal levels of plasma cortisol were also determined. After the feeding period, a stress test, consisting on 5 min of net chasing, was applied to a selected population of each dietary group. Total replacement of fish oil by vegetable oils did not induced changes in fish growth and performance, but affected fatty acid profile of muscle, liver, and intestine, reflecting those tissues the characteristic fatty acids of each type of dietary oil. A tendency to conserve the ARA/EPA ratio could be observed in the different tissues, despite of the level of these fatty acids in diet. Chasing stress induced an increase of muscle GR1 and a reduction in intestinal GR2 relative expressions at any of the experimental diets assayed. In liver, chasing stress induced an increase in both GR1 and GR2 gene expression in fish fed fish oil diets. Similarly, chasing stress induced an increase of muscle HSP70 and decrease of HSP90AB in liver at any of the experimental diet assayed. Besides, vegetable oils decreased the expression of HSP70 in intestine, being the relative expression of liver HSP90AA increased by the inclusion of linseed oil in the diet, at any of the experimental conditions assayed.

SHBG, plasma, and urinary androgens in weight lifters after a strength training.

Previous studies with different results have suggested that total and bioavailable testosterone levels are modified by physical exercise. Such changes may be related to modifications in cortisol levels and could be reflected in some urine androgens. To determine how weight lifting training may affect serum and urinary androgens, we measured total serum testosterone (T), cortisol, sex hormone binding globulin (SHBG) and urinary testosterone, epitestosterone, androsterone, and etiocholanolone, in a group of 19 elite weight lifters after 20 weeks of training. SHBG increased (from 27.5 +/- 9.5 to 34.7 +/- 8.1 nM, p < 0.05) whereas T/SHBG decreased significantly (from 1.10 +/- 0.4 to 0.85 +/- 0.3, p < 0.05). Serum total testosterone and cortisol did not change significantly. In urine, androsterone and etiocholanolone decreased significantly, whereas testosterone and epitestosterone remained unchanged. Changes in T/SHBG were related positively with changes in urinary androgens (r = 0.680, p < 0.01), and changes in SHBG were negatively related with changes in urinary androgens (r = -0.578, p < 0.01). These results suggest that intense physical activity may have an influence on the elimination of androgenic hormones due mainly to changes in their transporting protein SHBG.

SHBG, plasma, and urinary androgens in weight lifters after a strength training

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Previous studies with different results have suggested that total and bioavailable testosterone levels are modified by physical exercise. Such changes may be related to modifications in cortisol levels and could be reflected in some urine androgens. To determine how weight lifting training may affect serum and urinary androgens, we measured total serum testosterone (T), cortisol, sex hormonebinding globulin (SHBG) and urinary testosterone, epitestosterone, androsterone, and etiocholanolone, in a group of 19 elite weight lifters after 20 weeks of training. SHBG increased (from 27.5 ± 9.5 to 34.7 ± 8.1 nM, p < 0.05) whereas T/SHBG decreased significantly (from 1.10 ± 0.4 to 0.85 ± 0.3, p < 0.05). Serum total testosterone and cortisol did not change significantly. In urine, androsterone and etiocholanolone decreased significantly, whereas testosterone and epitestosterone remained unchanged. Changes in T/SHBG were related positively with changes in urinary androgens (r = 0.680, p < 0.01), and changes in SHBG were negatively related with changes in urinary androgens (r = −0.578, p < 0.01). These results suggest that intense physical activity may have an influence on the elimination of androgenic hormones due mainly to changes in their transporting protein SHBG (AU)

Extensive osteolysis caused by polyethylene particle migration in an anatomical hydroxyapatite-coated hip prosthesis: 10 years' follow-up.

We report our 10-year follow-up results of 630 consecutive Anatomique Benoist Giraud I hip prostheses implanted between June 1990 and December 1995. At this time, 520 were satisfactory and 25 had been revised. Although the majority of patients remained asymptomatic at the end of follow-up, the real survivorship of the implant was less than 91% (33 patients who were in the waiting list for revision due to osteolysis at that time were revised by December 2007). On the other hand, radiographic outcomes were of concern: around 90% of patients showed progressive stress shielding and large granulomatous lesions in the proximal femur, and more than 82% of patients exhibited polyethylene wear in excess of 1 mm (mean=1.69 mm).

Changes in periprosthetic bone remodelling after redesigning an anatomic cementless stem.

The aim of this prospective cohort study was to determine the densitometric relevance of minor design modifications of a cementless stem designed to improve proximal load transfer. We used a prospective cohort study with densitometric analysis over a five-year period of two groups of patients with primary osteoarthritis. The first group, 56 hips, received the first version of the ABG stem (ABG-I); the second group, 54 hips, had the ABG-II stem. The results obtained with the ABG-I stem showed a decrease of bone density in proximal areas that ranged from 13% to 37%. However, the new design had a decrease of the same areas that ranged from 9% to 23%. These differences were noted at the end of the first post-operative year and remained stable, except in zone 7, where they were progressive. There is little evidence that the modified stem reduces femoral bone density loss.

Multiple abscesses caused by Salmonella enterica and Corynebacterium pseudotuberculosis in a dromedary camel.

A rare case of arthritis, peri-arthiritis and pleurits associated with Salmonella enterica and Corynebacterium pseudotuberculosis infection in a dromedary camel is reported. Articular infections caused by Non-typhoidal Salmonella have been exceptionally described in human medicine. To our knowledge, this would be the first description of articular infections associated with Non-thyphoidal Salmonella in other mammals than humans. Possible pathogenesis of the infection is discussed.

Determination of urine steroid profile in untrained men to evaluate recovery after a strength training session.

Intense physical exercise is an important modifier of hormone metabolism. The aim of this study was to evaluate the variations in the urine profile of glucuroconjugated steroids (androgens, estrogens, and corticosteroids) as a consequence of a session of strength exercises. The subjects were a group (N = 20) of untrained male university students. They performed 3 sets of 10 repetitions, with a 3-minute recovery time between sets, at 70-75% of 1 repetition maximum (1RM). Four urine samples were collected per subject: before the session, immediately after, 3 hours after, and 48 hours after the session. They were assayed using a gas chromatograph coupled with a mass spectrometer. The concentrations of the different hormones were determined according to the urine creatinine level (ng steroid per mg creatinine). The substances assayed were testosterone, epitestosterone (Epit), androstenedione, dehydroepiandrosterone (DHEA), androsterone, etiocholanolone, beta-estradiol, estrone, tetrahydrocortisone (THE), and tetrahydrocortisol (THF). The results showed a significant decline after exercise with respect to the rested state in the urinary excretion of testosterone, Epit, DHEA, androsterone, and etiocholanolone. At 48 hours, there was a significant increase in the urinary excretion of Epit, androstenedione, androsterone, etiocholanolone, estrone, and THE. The androsterone + etiocholanolone/THE + THF ratio decreased after exercise, increased significantly (p < 0.05) at 3 hours, and returned to near resting levels at 48 hours. The data suggest that the performing a strength session at 70-75% of maximum strength provoked a state of fatigue in the subjects, from which they recovered 48 hours after the exercise.