Influence of endogenous and synthetic female sex hormones on human blood cells in vitro studied with comet assay

The comet assay has been conducted with numerous cell lines to assess in vitro genotoxicity. In order to use the comet assay as part of an in vitro test for evaluating genotoxicity, however, there are cell-specific factors that need to be better understood. In this present study we have evaluated some factors that may impact upon the DNA damage detected in whole blood (WB) cells and lymphocytes (ILs). Experiments were conducted comparing responses of both cells, and investigating the effects of the female hormonal cycle, and oral contraceptive (OC) use on DNA damage detection in the in vitro comet assay, at three sampling time. No significant differences were detected in the basal levels of DNA damage detected in ILs and WB cells from women OC users and non-users and from men. Basal DNA damage in ILs was unaffected by gender and stage of the menstrual cycle or the stage of the treatment schedule. Our results also indicated that the H2O2 induces DNA damage in human lymphocytes independently of gender, low-dose OC use and hormonal fluctuation. However, data showed that in 3rd sampling of menstrual cycle, lymphocytes were more resistant to H2O2-induced DNA damage than those from OC users and men. © 2007 Elsevier Ltd. All rights reserved.

Effects of atrazine on female Wistar rats: Morphological alterations in ovarian follicles and immunocytochemical labeling of 90 kDa heat shock protein

Fertility in female mammals may be affected by a variety of endocrine disrupters present in the environment. Herbicide atrazine is an example of endocrine disrupter employed in agriculture, which disrupts estrous cyclicity in rats. Aiming to characterize morphologically the effect of low and sublethal doses of atrazine on the ovaries of Wistar rats, in an effort to determine the possible intrafollicular target site through which this herbicide acts adult females were submitted to both subacute and subchronic treatments. Additionally, immunocytochemical labeling of 90 kDa heat shock protein (HSP90) was performed in order to evaluate the role played by this protein in the ovary, under stressed conditions induced by herbicide exposure. The results indicated that atrazine induced impaired folliculogenesis, increased follicular atresia and HSP90 depletion in female rats submitted to subacute treatment, while the subchronic treatment with low dose of atrazine could compromise the reproductive capacity reflected by the presence of multioocytic follicle and stress-inducible HSP90. © 2007 Elsevier Ltd. All rights reserved.

Perinatal exposure to parasiticide ivermectin: Long-term effects on reproductive parameters of adult male rats

Ivermectin is one of the most widely used antiparasitic drugs globally. The aim of this study was to evaluate the chronic effects of perinatal exposure to ivermectin on male reproductive parameters in rats. Pregnant rats were treated daily by oral gavage with 0.4 or 1.6 mg kg -1 of ivermectin or vehicle, from gestational day 6 until post-natal day 10. In the adulthood stage, there were significant reductions in the relative testicular weight of rats exposed to the low dose and in relative prostate weight of male rats exposed to the high dose of ivermectin. Furthermore, the animals exposed to the low dose also presented an increased seminal vesicle weight compared to controls. However, neither of the ivermectin doses interfered in daily sperm production, sperm number in testis, or sexual behavior of exposed males. In conclusion, perinatal exposure to ivermectin neither altered the male reproductive system development markedly, nor produced any adverse effects on the parameters evaluated. © 2011 Taylor & Francis.

Macrophage activity and histopathology of the lymphohematopoietic organs in male Wistar rats orally exposed to single or mixed pesticides

The noxious effects of low or effective dose exposure to single or mixed pesticides on macrophage activity and the lymphohematopoietic organs were investigated. Male Wistar rats were orally exposed to dichlorvos, dicofol, endosulfan, dieldrin and permethrin, either as single or combined mixtures during a 28-day study containing eight groups: one group received a semipurified diet (non-treated); two groups received a semipurified diet containing low dose mixture (dieldrin 0.025 mg/kg, endosulfan, 0.6 mg/kg, dicofol 0.22 mg/kg, dichlorvos 0.23 mg/kg, permethrin 5 mg/kg) or an effective dose mixture (dichlorvos 2.3 mg/kg, dicofol 2.5 mg/kg, endosulfan 2.9 mg/kg, dieldrin 0.05 mg/kg and permethrin 25.0 mg/kg), respectively; the other five groups received a semipurified diet containing each single pesticide in effective doses. At sacrifice, the thymus, spleen, mesenteric lymph nodes, Payer's patches and bone marrow were removed for histological analysis. Peritoneal macrophages were obtained to determine the phagocytosis and spreading indexes and tumoral necrosis factor alpha (TNF-α), nitric oxide (NO) and H2O2 production. Exposure to pesticide mixtures did not alter the percentage of macrophage phagocytosis and spreading, TNF-α production or the NO and H2O2 release when compared to the non-treated group. Neither was there any apparent evidence that a pesticide mixture at low or effective doses altered the histological structure of the lymphohematopoietic organs. The findings indicate that short-term treatment with pesticide mixtures did not induce an apparent immunotoxic effect in male Wistar rats. © 2013 Copyright Taylor and Francis Group, LLC.

Organically produced coffee exerts protective effects against the micronuclei induction by mutagens in mouse gut and bone marrow

While researchers have extensively evaluated the beneficial effects of coffee consumption in reducing the frequency of certain diseases, studies examining the differences between organic and conventional coffee intake are still needed. Therefore, this paper aims to investigate the functional effects of organic and conventional coffee by examining both its chemical composition and its mutagenic/antimutagenic properties. Infusions of 10% or 20% (w/v) of organic and conventional coffee were administered by gavage (10 mL/kg b.w., once or twice a day) to male Swiss mice against doxorubicin (DXR) and 1,2-dimethylhydrazine dihydrochloride (DMH)-induced mutagenicity. The levels of chlorogenic acids, caffeine and trigonelline from the coffee infusions and oxidative stress analysis from the liver were measured by HPLC. Gut and bone marrow micronucleus assays were used as mutagenic/antimutagenic endpoints, as well as the crypt measurements and gut apoptosis index. The in vivo tests revealed that only organic coffee exerted protective effects, despite oxidative stress analysis and crypt measurements not showing differences among treatments. Intriguingly, the low dose (10% w/v mL/kg) displayed a robust protective effect that showed a significant reduction in bone marrow micronuclei (26.8%), gut micronuclei (11.5%) and apoptosis (27.8%), whereas the higher coffee dose (2 × 20% w/v) only showed a protective effect against bone marrow micronucleus (43.7%). These results highlight that organic coffee could be considered to have beneficial functional effects, although it is still a challenge to define conclusions from analytical data and all the possible interactions from this complex food matrix. © 2013 Elsevier Ltd. All rights reserved.

Facilitation of sodium intake by combining noradrenaline into the lateral parabrachial nucleus with prazosin peripherally

Injections of noradrenaline into the lateral parabrachial nucleus (LPBN) increase arterial pressure and 1.8% NaCl intake and decrease water intake in rats treated with the diuretic furosemide (FURO) combined with a low dose of the angiotensin converting enzyme inhibitor captopril (CAP). In the present study, we investigated the influence of the pressor response elicited by noradrenaline injected into the LPBN on FURO + CAP-induced water and 1.8% NaCl intake. Male Holtzman rats with bilateral stainless steel guide-cannulas implanted into LPBN were used. Bilateral injections of noradrenaline (40 nmol/0.2 μl) into the LPBN increased FURO + CAP-induced 1.8% NaCl intake (12.2 ± 3.5, vs., saline: 4.2 ± 0.8 ml/180 min), reduced water intake and strongly increased arterial pressure (50 ± 7, vs. saline: 1 ± 1 mm Hg). The blockade of the α1 adrenoceptors with the prazosin injected intraperitoneally abolished the pressor response and increased 1.8% NaCl and water intake in rats treated with FURO + CAP combined with noradrenaline injected into the LPBN. The deactivation of baro and perhaps volume receptors due to the cardiovascular effects of prazosin is a mechanism that may facilitate water and NaCl intake in rats treated with FURO + CAP combined with noradrenaline injected into the LPBN. Therefore, the activation of α2 adrenoceptors with noradrenaline injected into the LPBN, at least in dose tested, may not completely remove the inhibitory signals produced by the activation of the cardiovascular receptors, particularly the signals that result from the extra activation of these receptors with the increase of arterial pressure. © 2013 Elsevier Inc.

Efeitos do treinamento físico sobre aspectos endócrino-metabólicos de ratos administrados com dexametasona

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Insuficiência aórtica subcrônica e vias centrais relacionadas à regulação da ingestão de sódio

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Respostas cardiovasculares e na ingestão de água e NaCl hipertônico em ratos com doença periodontal tratados com agonista GABAA no núcleo parabraquial lateral

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da cultura do milho e da decomposição da palhada submetida à Hormesis

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

Densidade mineral óssea em adolescentes usuárias de anticoncepcional oral combinado

Pós-graduação em Ginecologia, Obstetrícia e Mastologia - FMB

Mecanismos prosencefálicos envolvidos na ingestão de sódio e água induzida pela ativação gabaérgica do núcleo parabraquial lateral

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeitos cardiovasculares e na ingestão de NaCl e água induzida pela injeção de trans-4-aminocrotonic acid (TACA) no núcleo parabraquial lateral (NPBL) de ratos

Pós-graduação em Ciências Fisiológicas - FOA

Proteção renal com eritropoetina em modelo de isquemia renal no rato

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ação de biorreguladores na brotação, produção e algumas características físico-químicas de uva do cultivar Superior Seedless

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)