Androgenicity and venous endothelial function in post-menopausal women

Background: Endothelial dysfunction is one of the early signs of cardiovascular damage. High androgen levels have been related to inflammatory endothelial markers in pre- and post-menopausal women. Aim: This cross-sectional study aimed at investigating whether free androgen index (FAI) [estimated by dividing total testosterone (nmol/l) by SHBG (nmol/l) x 100] is related to endothelial function during post-menopause. Subjects and methods: Twenty-six post-menopausal women were assessed with the dorsal hand vein compliance technique. Acetylcholine (Ach) and sodium nitroprusside (SNP) dose-response curves were constructed to test endothelium-dependent and independent relaxation, respectively. Results: Mean age was 54 yr ( 4) and median time since menopause was 6 yr (interquartile range: 3-9). Patients were stratified according to FAI levels into two groups: FAI greater than or less than the group median of 2.5. Waist-to-hip ratio (WHR) was significantly higher in the group with FAI>2.5, as well as median dose of Ach for maximal vasodilation [720 (360-3600) ng/min with FAI>2.5 vs 36 (0.36-360) ng/min with FAI <= 2.5; p=0.005]. Maximal vasodilation with SNP was similar in both groups. Positive correlations were observed between Ach doses and maximal vasodilation and FAI (r=0.473, p=0.015), waist (r=0.510, p= 0.011), and WHR (r=0.479, p=0.021). SHBG was negatively correlated with Ach doses (rs=-0.400, p=0.043). Conclusions: This study suggests that FAI, even within normal limits, is related to early changes in endothelial function in healthy post-menopausal women. Longitudinal studies are required to determine the clinical relevance of these findings. (J. Endocrinol. Invest. 33: 239-243, 2010) (C) 2010, Editrice Kurtis

Annual profile of fecal androgen and glucocorticoid levels in free-living male American kestrels from southern mid-latitude areas

Fecal samples and behavioral data were collected at a fortnightly basis during 11 months period from free-living male American kestrels living in southeast Brazil (22 degrees S latitude). The aim was to investigate the seasonal changes in testicular and adrenal steroidogenic activity and their correlation to reproductive behaviors and environmental factors. The results revealed that monthly mean of fecal glucocorticoid metabolites in May and June were higher than those estimated in November. in parallel, monthly mean of androgen metabolites in September was higher than those from January to April and from October to November. Molt took place from January to March, whereas copulation was observed from June to October but peaked in September. Nest activity and food transfer to females occurred predominantly in October, and parental behavior was noticed only in November. Territorial aggressions were rare and scattered throughout the year. Multiple regression analysis revealed that fecal androgen levels are predicted by photoperiod and copulation, while fecal glucocorticoid levels are only predicted by photoperiod. Bivariate correlations showed that fecal androgen metabolites were positively correlated with fecal glucocorticoid metabolites and copulation, but negatively correlated with molt. Additionally, copulation was positively correlated with food transfer to females and nest activity, but negatively correlated with molt. These findings suggest that male American kestrels living in southeast Brazil exhibit significant seasonal changes in fecal androgen and glucocorticoid concentrations, which seem to be stimulated by decreasing daylength but not by rainfall or temperature. (C) 2009 Elsevier Inc. All rights reserved.

Inflammation and adipose tissue: effects of progressive load training in rats

Introduction: Cytokines (IL-6, IL-10 and TNF-alpha) are increased after exhaustive exercise in the rat retroperitoneal (RPAT) and mesenteric adipose tissue (MEAT) pads. On the other hand, these cytokines show decreased expression in these depots in response to a chronic exercise protocol. However, the effect of exercise with overload combined with a short recovery period on pro-and anti-inflammatory cytokine expression is unknown. In the present study, we investigated the regulation of cytokine production in the adipose tissue of rats after an overtraining-inducing exercise protocol. Methods: Male Wistar rats were divided into four groups: Control (C), Trained (Tr), Overtrained (OT) and recovered overtrained (R). Cytokines (IL-6, TNF-alpha and IL-10) levels and Toll Like Receptor 4 (TLR4), Nuclear Factor kBBp65 (NF-kBp65), Hormone Sensitive Lipase (HSL) and, Perilipin protein expression were assessed in the adipose tissue. Furthermore, we analysed plasma lipid profile, insulin, testosterone, corticosterone and endotoxin levels, and liver triacylglycerol, cytokine content, as well as apolipoprotein B (apoB) and TLR4 expression in the liver. Results: OT and R groups exhibited reduced performance accompanied by lower testosterone and increased corticosterone and endotoxin levels when compared with the control and trained groups. IL-6 and IL-10 protein levels were increased in the adipose tissue of the group allowed to recover, in comparison with all the other studied groups. TLR-4 and NF-kBp65 were increased in this same group when compared with both control and trained groups. The protein expression of HSL was increased and that of Perilipin, decreased in the adipose in R in relation to the control. In addition, we found increased liver and serum TAG, along with reduced apoB protein expression and IL-6 and IL-10 levels in the of R in relation to the control and trained groups. Conclusion: In conclusion, we have shown that increases in pro-inflammatory cytokines in the adipose tissue after an overtraining protocol may be mediated via TLR-4 and NF-kBp65 signalling, leading to an inflammatory state in this tissue.

Anabolic-androgenic steroid treatment induces behavioral disinhibition and downregulation of serotonin receptor messenger RNA in the prefrontal cortex and amygdala of male mice

Nandrolone is an anabolic-androgenic steroid (AAS) that is highly abused by individuals seeking enhanced physical strength or body appearance. Supraphysiological doses of this synthetic testosterone derivative have been associated with many physical and psychiatric adverse effects, particularly episodes of impulsiveness and overt aggressive behavior. As the neural mechanisms underlying AAS-induced behavioral disinhibition are unknown, we investigated the status of serotonergic system-related transcripts in several brain areas of mice receiving prolonged nandrolone administration. Male C57BL/6J mice received 15 mg/kg of nandrolone decanoate subcutaneously once daily for 28 days, and different sets of animals were used to investigate motor-related and emotion-related behaviors or 5-HT-related messenger RNA (mRNA) levels by real-time quantitative polymerase chain reaction. AAS-injected mice had increased body weight, were more active and displayed anxious-like behaviors in novel environments. They exhibited reduced immobility in the forced swim test, a higher probability of being aggressive and more readily attacked opponents. AAS treatment substantially reduced mRNA levels of most investigated postsynaptic 5-HT receptors in the amygdala and prefrontal cortex. Interestingly, the 5-HT(1B) mRNA level was further reduced in the hippocampus and hypothalamus. There was no alteration of 5-HT system transcript levels in the midbrain. In conclusion, high doses of AAS nandrolone in male mice recapitulate the behavioral disinhibition observed in abusers. Furthermore, these high doses downregulate 5-HT receptor mRNA levels in the amygdala and prefrontal cortex. Our combined findings suggest these areas as critical sites for AAS-induced effects and a possible role for the 5-HT(1B) receptor in the observed behavioral disinhibition.

Gonad development and hormone titres in Loggerhead Sea Turtles (Caretta caretta) in the NE Atlantic

The study proposed to describe sexual development in pelagic stage loggerhead sea turtles Caretta caretta and compare this to hatchlings and adults. It is meant as an ontogenic approach, in order to understand reproductive development and population composition and their dynamics in the pelagic environment. The study focused on the pelagic loggerheads that are found in the waters offshore Madeira Island (Portugal) in the North-eastern Atlantic and use it as a developmental habitat. The innovating character of this work relied on the lack of any description regarding the gonad ontogenesis and reproductive development for the pelagic stage in any of the 7 existing sea turtle species, all of them in danger of extinction. Three methods were used to diagnose the sex of each juvenile individual and asses the level of reproductive development: (1) laparoscopy, (2) gonad biopsy and (3) the assessment of two sex steroids circulating levels, namely testosterone and estradiol. In order to cover all life stages and compare data obtained for the juvenile stage, hatchlings and nesting female adults were sampled at the nearest nesting rookery at Boa Vista Island in the Cape Verde Archipelago. Gonads from dead hatchlings were collected for gonad histology and blood was collected from nesting females for sex steroids assessment. Laparoscopies revealed to be a valid sexing method for the juvenile stage, since gonads are morphologically differentiated at these size classes. Moreover, laparoscopy was validated using gonad histology. Gonad histology of juveniles showed that gonads are already completely differentiated into ovaries or testes at the size classes examined, but development seems to be quiescent. Males present already developed seminiferous tubules with spermatogonia lining the interior of the seminiferous tubule. Female gonads present oocytes at different development stages, but only oocytes up to stage III were observed. The maximum oocyte diameter in each individual correlated with body size, suggesting that reproductive development is an on-going process in juvenile females. The circulating levels of both testosterone and estradiol in juveniles of both sexes were very low and consistently lower than the ones observed in the nesting females from Boa Vista Island. No bimodal distribution was found for any of the sex steroids analysed and thus circulating hormone levels were not a reliable tool for sexing juvenile individuals with a non-invasive technique. The ratio testosterone:estradiol did not show a bimodal distribution either. The levels of testosterone correlated with sea surface temperature. The fact that temperatures observed during this study were below 24ºC might have hindered a differential testosterone pattern between juvenile males and females. Sex ratios for this population were generated according to laparoscopy results and compared among years and size classes. An overall sex ratio of 2 females for each male was found, but they varied among size classes but not among years. Possible causes for the sex ratios observed are discussed. This study is a contribution to our knowledge on the pelagic stage of loggerhead turtles, namely on the population structure regarding sex ratio, which is a vital tool for implementing conservation strategies.

Testicular volume and reproductive status of Wild Callithrix jacchus

ARAÚJO, Arrilton ; SOUSA, Maria Bernardete Cordeiro . Testicular volume and reproductive status of Wild Callithrix jacchus. International Journal of Primatology, v.29, p.1355–1364, 2008. DOI 10.1007/s10764-008-9291-4

Influência da estação do ano nas características do sêmen e na concentração de hormônios em touros Nelore e Simental

Estudou-se a influência das quatro estações do ano nas características do sêmen e nas concentrações de testosterona e cortisol em touros. Cinco touros Nelore e cinco Simental entre 48 e 72 meses de idade, criados extensivamente, foram avaliados andrologicamente por meio de exames físicos das características morfológicas do sêmen e das concentrações séricas de testosterona e cortisol. Houve redução na motilidade e no vigor do sêmen no inverno (P<0,05) na raça Simental. Observou-se correlação (P<0,01) entre testosterona x motilidade (0,69) e testosterona x vigor (0,57) na raça Simental, e cortisol x motilidade (0,68) e cortisol x vigor (0,65) na raça Nelore. O efeito das estações do ano modificou a qualidade do sêmen com aumento da motilidade e vigor espermáticos na primavera e verão nos touros Simental. A concentração de cortisol diminuiu no outono nos touros Nelore.

Chronic exposure to sub-lethal concentration of a glyphosate-based herbicide alters hormone profiles and affects reproduction of female Jundia (Rhamdia quelen)

This work was carried out to verify the effect of a glyphosate-based herbicide on Jundia hormones (cortisol, 17 beta-estradiol and testosterone), oocyte and swim-up fry production. Earthen ponds containing Jundia females were contaminated with glyphosate (3.6 mg/L); blood samples were collected from eight females from each treatment immediately before, or at 1, 10, 20 30 and 40 days following contamination. A typical post-stress rise in cortisol levels was observed at the 20th and 40th days following exposure to glyphosate. At the 40th day, 17 beta-estradiol was decreased in the exposed females. A similar number of oocytes were stripped out from females from both groups, however, a lower number of viable swim-up fry were obtained from the herbicide exposed females, which also had a higher liver-somatic index (LSI). The results indicate that the presence of glyphosate in water was deleterious to Rhamdia quelen reproduction, altering steroid profiles and egg viability. (c) 2006 Elsevier B.V. All rights reserved.

Concentrações de hormônio na carcaça de tilápias-do-nilo e maturação precoce após reversão sexual

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Testosterona e gonadotrofina coriônica humana estimulam a esteroidogênese em células da granulosa de folículo pré-ovulatório de égua?

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morfometria de testículos escrotais, abdominais e inguinais de eqüinos criptórquios unilaterais

Foi realizado um estudo morfométrico de testículos escrotais e retidos de 10 eqüinos criptórquios unilaterais, sendo cinco abdominais e cinco inguinais. As características avaliadas foram espessura da albugínea testicular, área dos túbulos seminíferos e número de células de Leydig. A espessura da albugínea testicular mostrou-se reduzida (P< 0,05) nas gônadas criptórquias abdominais quando comparadas às escrotais contralaterais. Também foram observadas diferenças (P< 0,01) nas áreas dos túbulos seminíferos dos testículos abdominais e inguinais, que se apresentaram diminuídas quando comparadas às dos escrotais contralaterais. A diminuição foi de, aproximadamente, 45% nos testículos abdominais e de 31% nos inguinais. Não foram verificadas diferenças (P> 0,05) na contagem de células de Leydig das gônadas criptórquias comparadas às escrotais contralaterais. Nos eqüinos, o criptorquismo afetou com maior intensidade a área dos túbulos seminíferos dos testículos abdominais e inguinais e a espessura da albugínea daqueles retidos no abdome.

Steroidogenesis in cumulus cells of bovine cumulus-oocyte-complexes matured in vitro with BSA and different concentrations of steroids

The present in vitro experiments were designed to evaluate the ability of bovine cumulus-oocyte-complexes (COCs)to produce steroids and also to evaluate the modulatory effects of added estradiol, progesterone and testosterone on the steroidogenic activity of COCs. Considerable estradiol accumulation was observed in the control maturation medium for in vitro maturation of bovine COCs during the 24h of maturation (P < 0.05). When testosterone was added to the medium at various concentrations, a slight estradiol accumulation occurred, which, however, was lower (P < 0.05) than that observed in the control medium. Slight estradiol accumulation was observed in maturation medium containing progesterone at concentrations of 2.5, 5.0 and 10.0 mug/ml, but these increases were less (P < 0.05) than those observed in the control medium. However, in the presence of 1.0 mug/ml progesterone, estradiol accumulation was equal to that of the control medium (P > 0.05). Progesterone accumulation (P < 0.05) was observed in the control medium for in vitro maturation of bovine COCs. When estradiol was added to the maturation medium, progesterone accumulation was observed, but was significant (P < 0.05) only when the medium was supplemented with the lesser concentrations of estradiol utilized in the experiment (1.0 mug/ml). The results demonstrated that (1) cumulus cells of bovine COCs are able to secrete estradiol and progesterone in culture systems for in vitro maturation, and this steroidogenesis is modulated by the steroids progesterone, testosterone and estradiol, and (2) the addition of estradiol to the in vitro maturation medium of bovine oocytes should be reviewed, since cumulus cells of COCs have been demonstrated to secrete estradiol in the maturation medium. (C) 2002 Elsevier B.V. B.V. All rights reserved.

Criptorquismo em eqüinos: aspectos clínico-cirúrgicos e determinação da testosterona sérica

Alguns aspectos clínico-cirúrgicos do criptorquismo foram investigados em 42 eqüinos. A freqüência da afecção foi elevada em cavalos Mangalarga, Quarto de Milha e sem raça definida que, em conjunto, totalizaram 73,8% dos casos. O criptorquismo abdominal (64,3%) predominou sobre o inguinal (35,7%). A retenção unilateral ocorreu na maioria dos casos (95,2%), com prevalência do criptorquismo abdominal unilateral esquerdo (45,2%). Também foi determinada a concentração da testosterona sérica em seis garanhões normais (grupo I) em plena atividade sexual (grupo-controle) e em 10 criptórquios (grupos II e III, respectivamente, cinco abdominais e cinco inguinais). A dosagem da testosterona sérica não revelou diferença (P> 0,05) entre os três grupos. Os achados indicam que a produção desse hormônio permanece inalterada no criptórquio, justificando seu comportamento sexual, semelhante ao do garanhão normal.

Efeitos dos esteroides anabólicos androgênicos sobre o útero e parâmetros reprodutivos de ratas adultas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)