Morphomettic changes on honeybee Apis mellifera L. workers fat body cells after juvenile hormone topic application at emergence

The effect of topical application of juvenile hormone (JH) over the lifetime of worker bees was evaluated in Apis mellifera, by measuring the area of the two cell types, trophocytes and oenocytes, found in the fat body. Topical application of 1 mu l of a 1 mu g/mu l solution of JH in acetone to the abdomens of newly emerged workers produced an increase in cell size, in both types of cell of 5-day-old treated workers in relation to the untreated control. The treatment was more effective on the oenocytes, since there were significant differences compared to the averages of the treatments and the interaction of the treatments with the age of the workers. The developmental pattern seemed to differ from the treated group. However, subsequent effects were probably dependent on different, natural variations in hormonal levels. (c) 2007 Elsevier Ltd. All rights reserved.

Efeitos do treinamento aeróbio sobre o perfil lipídico de ratos com hipertireoidismo

Há poucos estudos analisando a importante relação entre o exercício físico, agudo e crônico, e alterações metabólicas decorrentes do hipertireoidismo. O objetivo do presente estudo foi analisar o efeito de quatro semanas de treinamento aeróbio sobre o perfil lipídico de ratos com hipertireoidismo experimental. Foram utilizados 45 ratos da linhagem Wistar, divididos aleatoriamente em quatro grupos: Controle Sedentário (CS) - administrados com salina durante o período experimental, não praticaram exercício físico (n = 12); Controle Treinado (CT) - administrados com salina, participaram do treinamento (n = 11); Hipertireoidismo Sedentário (HS) - induzidos ao hipertireoidismo, não praticaram exercício físico (n = 12); e Hipertireoidismo Treinado (HT) - induzidos ao hipertireoidismo, participaram do treinamento (n = 10). O treinamento aeróbio teve duração de quatro semanas, cinco vezes na semana, com duração de uma hora por sessão. Após o término do período experimental todos os ratos foram anestesiados em câmara de CO2 até sua sedação. Coletaram-se amostras de sangue para dosagem de colesterol total, triglicerídeos, HDL-colesterol e LDL-colesterol e hormônio T3; e amostras do coração, fígado, músculo gastrocnêmio e tecido adiposo das regiões mesentérica, retroperitonial e subcutânea para pesagem e dosagem de triglicerídeos. Para análise estatística utilizou-se ANOVA two-way, seguida do post hoc LSD de Fischer. Observaram-se menores valores de AGL no grupo HS quando comparado ao CS. O grupo HS teve nível de triglicerídeos significativamente superior nas regiões mesentérica, do gastrocnêmio e retroperitonial quando comparado com os grupos CS e CT, e apenas o tecido adiposo da região retroperitonial apresentou diferenças significativas na qual o grupo HT apresentou menor peso quando comparado com o grupo CS. Pode-se concluir que os ratos hipertireoidicos apresentaram perfil lipídico diferente dos ratos controle, e o treinamento aeróbio em ratos Wistar pode ter alterado o perfil lipídico dos animais com hipertireoidismo experimental quando comparados com o grupo sedentário e grupos controle.

Effects of Exercise Training on Hippocampus Concentrations of Insulin and IGF-1 in Diabetic Rats

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

Growth factors and glucose homeostasis in diabetic rats: effects of exercise training

To investigate the alterations of glucose homeostasis and variables of the insulin-like growth factor-I (IGF- 1) growth system in sedentary and trained diabetic (TD) rats, Wistar rats were divided into sedentary control (SC), trained control (TC), sedentary diabetic (SD), and TD groups. Diabetes was induced by Alloxan (35 mg kg(-1) b.w.). Training program consisted of swimming 5 days week(-1), 1 h day(-1), during 8 weeks. Rats were sacrificed and blood was collected for determinations of serum glucose, insulin, growth hormone (GH), IGF-1, and IGF binding protein-3(IGFBP-3). Muscle and liver were removed to evaluate glycogen content. Cerebellum was extracted to determinate IGF-1 content. Diabetes decreased serum GH, IGF-1, IGFBP-3, liver glycogen, and cerebellum IGF-1 peptide content in baseline condition. Physical training recovered liver glycogen and increased serum and cerebellum IGF-1 peptide in diabetic rats. Physical training induces important metabolic and hormonal alterations that are associated with an improvement in glucose homeostasis and serum and cerebellum IGF-1 concentrations. Copyright (C) 2009 John Wiley & Sons, Ltd.

Tissue evidence of the testosterone role on the abnormal growth and aging effects reversion in the gerbil (Meriones unguiculatus) prostate

Prostate differentiation during embryogenesis and its further homeostatic state maintenance during adult life depend on androgens. Abundant biological data suggest that androgens play an important role in the development of the prostate cancer and other prostatic diseases. The objective of this work was to evaluate the effects of the testosterone supplementation in gerbil (a new experimental model) at different ages. Tissues from experimental animals were studied by histological and histochemistry procedures, androgen receptor immunohistochemistry assay, morphometric-stereological analysis, and transmission electron microscopy (TEM). After the treatment were observed increase of prostate weight and epithelium height in all ages studied. In some adult and aged treated animals, hyperplasic and displasic process were observed, including prostatic intraepithelial neoplasias and adenocarcinomas. Increase of the thickness of the smooth muscle cell (SMC) layer was observed in pubescent and adult animals and TEM revealed apparent SMC hypertrophy. An apparent increase in the frequency of blood vessels distributed by the subepithelial stroma in the treated animals was noticed. Reversion of the natural effects of aging on the prostate was observed in the aged treated animals in some acini of the gland. These data demonstrate that the gerbil prostate is susceptible to androgenic action at the studied ages and it can serve, for example, as experimental model to studies of prostate neoplasic process induction and hormonal therapy in aged animals.

Acid phosphatase activity in gerbil prostate: comparative study in male and female during postnatal development

The prostate is present in both male and female mammals. It is composed of secretory epithelium, connective stroma, smooth muscle and neuroendocrine cells, which are under hormonal regulation. Acid phosphatases catalyze the hydrolysis of orthophosphate monoesters. We have compared the expression of acid phosphatases in gerbil (Meriones unguiculatus) prostate glands in both sexes using young, adult and old animals. Eighteen prostates were isolated, frozen, sectioned, fixed, incubated with sodium beta-glycerophosphate sodium, washed with acetate buffer solution, treated with ammonium sulfide and counterstained with Methyl-Green aqueous solution. Ultracytochemical analyses were also conducted. This substrate revealed total acid phosphatase activity. The expression of the enzyme was heterogeneous, occurring in all ages during postnatal development. The data. revealed that the female prostate matured before the male prostate. In addition, acid phosphatase activity in both sexes was regulated by androgen variation concomitant with development. (C) 2004 International Federation for Cell Biology. Published by Elsevier Ltd. All rights reserved.

Cellular and extracellular behavior in the gerbil (Meriones unguiculatus) ventral prostate following different types of castration and the consequences of testosterone replacement

Mongolian gerbils (Meriones unguiculatus) were grouped into two experimental groups: GEx.01 suffered orchiectomy and after 30 days received doses of testosterone cipionate (T), while GEx.02 received weekly and alternated doses of the anti-androgens cyproterone acetate and flutamide for 30 days, and the animals were then euthanized. Structural evaluation reveals a more intense reduction in epithelial height in GEx.02. Smooth muscle cells (SMC) presented a star-shaped aspect after 30 days of hormonal ablation and basal membrane was shown to be more intensely grooved in GEx.01. In both groups, after hormonal replacement, recovery in epithelial height could be noted and the SMC presented its phenotypes, but an increase in RER was seen, characterizing a modulation from its contractile to secreting phenotype. In conclusion, the prostate presented involution capacity after androgen ablation and the ability to reorganize after hormonal replacement, but events resulting from orchiectomy and subsequent T replacement were shown to be more aggressive to the prostate. (c) 2006 International Federation for Cell Biology. Published by Elsevier Ltd. All rights reserved.

Avaliação do perfil hematológico de portadores de talassemia alfa provenientes das regiões Sudeste e Nordeste do Brasil

A talassemia alfa é uma anemia hereditária resultante da síntese deficiente de cadeias alfa, provocando um excesso relativo de cadeias beta, que vão formar tetrâmeros identificados como hemoglobina H (Hb H) no indivíduo adulto. Para direcionar o diagnóstico laboratorial desta anemia, a análise dos índices eritrocitários, a eletroforese em acetato de celulose em pH neutro e a pesquisa de corpos de inclusão de Hb H são essenciais. O objetivo deste estudo foi traçar o perfil hematológico, por meio dos índices eritrocitários, dos portadores de talassemia alfa das regiões Sudeste e Nordeste do Brasil. Foram analisadas 1.010 amostras de sangue periférico após consentimento informado. Os índices eritrocitários como contagem de glóbulos vermelhos (RBC), dosagem de hemoglobina (HGB), hematócrito (HCT), volume corpuscular médio (VCM), hemoglobina corpuscular média (HCM) e concentração de hemoglobina corpuscular média (CHCM) foram fornecidos por aparelhos automatizados com controle de qualidade interno e externo. Para o diagnóstico de talassemia alfa foram utilizados testes de triagem e complementares para talassemias, como eletroforese em pH neutro e pesquisa de corpos de inclusão de Hb H com coloração de azul cresil brilhante. Comparando-se os valores hematológicos observados nos dois grupos, notou-se que, em ambas as regiões, os índices com valores discrepantes foram os níveis de HGB e HCT, sendo a maior freqüência de variação observada entre as mulheres. Nos portadores do fenótipo alfa talassêmico da região Nordeste, todos os índices eritrocitários estavam abaixo dos valores de normalidade. Estes resultados evidenciam a necessidade de melhor avaliação do perfil hematológico de talassemia alfa em diferentes regiões, considerando-se os interferentes ambientais para um diagnóstico mais preciso.

Visual communication stimulates reproduction in Nile tilapia, Oreochromis niloticus (L.)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Age-related histopathological lesions in the Mongolian gerbil ventral prostate as a good model for studies of spontaneous hormone-related disorders

The Meriones unguiculatus (Mongolian) gerbil has demonstrated significant prostatic responses to hormonal treatments, and to drugs against human prostatic hyperplasia Spontaneous neoplasia develops in the older animals. Thirty gerbils (age 18 months) were divided into non-affected and prostatic lesion bearers and the prostate lesions were evaluated morphologically, immunohistochemically and quantitatively. The most frequent changes were in epithelial sites and, namely prostatic intraepithelial neoplasias, microinvasive carcinomas and adenocarcinomas. In the stromal compartment, cellular hyperplasia, when verified, was always associated with the sites of anomalous epithelium. Additionally, larger deposition of collagen fibrils, generating stromal fibrosis, was found in all the old gerbils analysed. The quantitative analysis showed that prostatic tissue proportions differed in altered areas, being specific for each lesion type. Isolated nuclear and nucleolar parameters were not effective in diagnosing the malign potential of lesions. However, the cellular proliferation and death indexes indicated larger cellular turnover in invasive lesions such as carcinomas. With these analyses, it could be verified that old gerbils present high propensity to develop spontaneous prostate changes and this may aid in a better understanding of the biological behaviour of human prostate cancer.

Antiestrogen therapies affect tissue homeostasis of the gerbil (Meriones unguiculatus) female prostate and ovaries

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Microscopic evaluation of proliferative disorders in the gerbil female prostate: Evidence of aging and the influence of multiple pregnancies

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Tissue changes in senescent gerbil prostate after hormone deprivation leads to acquisition of androgen insensitivity

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

Oestrogen supplementation following castration promotes stromal remodelling and histopathological alterations in the Mongolian gerbil ventral prostate

The effect of oestradiol on the intact and castrated adult gerbil prostate was evaluated by focussing on stromal and epithelial disorders, and hormonal receptor immunoreactivity. The experimental animals were studied by histological, histochemical and immunohistochemical techniques, morphometric-stereological analysis and transmission electron microscopy. Epithelial alterations in the oestradiol-treated animals were frequent, with an increase in epithelial cell height, areas of intense dysplasia and hyperplasia and formation of prostatic intraepithelial neoplasia (PIN). Another aspect that did not depend on the presence of testosterone was the arrangement of the fibrillar and non-fibrillar elements of the extracellular matrix among smooth muscle cells (SMC), suggesting a possible role of these cells in rearrangement and synthesis of these components, after oestrogenic treatment. In the castrated animals, an accumulation of extracellular matrix elements under the epithelium was evident, while in the intact animals the same compounds were dispersed and scarce. In the groups of intact and castrated animals, SMC and fibroblasts exhibited a secretory phenotype, which was accentuated after oestradiol administration. There was an increase of the immunoreactivity to alpha-oestrogen and androgen receptors in hyperplastic areas compared to normal epithelium, revealing the involvement of these steroid receptors in the hyperplasia and PIN development.

Androgen receptor in the Mongolian gerbil ventral prostate: Evaluation during different phases of postnatal development and following androgen blockage

The normal growth, differentiation and maintenance of the morphofunctional integrity of the prostate gland are dependent on the interaction of constant levels of androgens with their receptors. The need to study the responses to hormones under several conditions and the effect of their blockage is due to the fact that the human prostate is the site of a great number of age-related diseases, and the ones with a major medical importance are prostate cancer (Cap) and benign prostatic hyperplasia (BPH), which can both be treated with androgen suppression. Seventy-five male gerbils were divided, randomly, into 3 groups of 25 animals each, where each group corresponded to one phase of postnatal development. In each phase, it was possible to morphologically and stereologically analyze the compartments of prostatic ventral lobe, as well as to immunohistochemically analyze the degree of expression of androgen receptors (ARs) after the androgen blockage therapies. In addition, it was possible to establish the hormonal dosage of serum testosterone levels given the comparative approach of the expression of androgen receptors. There is a pattern of AR distribution in the prostatic ventral lobe throughout postnatal development, in which the younger the animal is the higher, the interaction of circulating androgens that stimulate the AR expression in both the epithelial and stromal compartments. The androgen blockage therapies decreased AR expression in the prostatic compartments, but the androgen reposition after these blockages was not sufficient to recover the glandular structure or stimulate the AR expression up to normal physiological conditions. Both the regulation and distribution of androgen receptors along the gerbil prostatic tissues are complex mechanisms that are likely to be genetically regulated by androgens prenatally or by other factors that are still unknown. This rodent species seems to be a valuable model in the attempt to improve the understanding of the morphophysiological and pathological behavior of this important gland in humans throughout aging and to stimulate new therapeutic ideas to fight prostate cancer. (C) 2008 Elsevier Ltd. All rights reserved.