Overexpression of mitochondrial sirtuins alters glycolysis and mitochondrial function in HEK293 cells

SIRT3, SIRT4, and SIRT5 are mitochondrial deacylases that impact multiple facets of energy metabolism and mitochondrial function. SIRT3 activates several mitochondrial enzymes, SIRT4 represses its targets, and SIRT5 has been shown to both activate and repress mitochondrial enzymes. To gain insight into the relative effects of the mitochondrial sirtuins in governing mitochondrial energy metabolism, SIRT3, SIRT4, and SIRT5 overexpressing HEK293 cells were directly compared. When grown under standard cell culture conditions (25 mM glucose) all three sirtuins induced increases in mitochondrial respiration, glycolysis, and glucose oxidation, but with no change in growth rate or in steady-state ATP concentration. Increased proton leak, as evidenced by oxygen consumption in the presence of oligomycin, appeared to explain much of the increase in basal oxygen utilization. Growth in 5 mM glucose normalized the elevations in basal oxygen consumption, proton leak, and glycolysis in all sirtuin over-expressing cells. While the above effects were common to all three mitochondrial sirtuins, some differences between the SIRT3, SIRT4, and SIRT5 expressing cells were noted. Only SIRT3 overexpression affected fatty acid metabolism, and only SIRT4 overexpression altered superoxide levels and mitochondrial membrane potential. We conclude that all three mitochondrial sirtuins can promote increased mitochondrial respiration and cellular metabolism. SIRT3, SIRT4, and SIRT5 appear to respond to excess glucose by inducing a coordinated increase of glycolysis and respiration, with the excess energy dissipated via proton leak. © 2014 Barbi de Moura et al

Studies of Copaifera luetzelburgii Harms in reproductive pharmacology: In vivo and in vitro approaches

The objective of this study was to evaluate the estrogenic and anti-estrogenic actions, as well as the reproductive and foetal toxicity, of the ethanol extract from Copaifera luetzelburgii (EEtOH-Cl). In the experiment of (anti) estrogenicity, nulliparous Wistar rats were treated for 3 days with EEtOH-Cl (125, 250 and 500 mg/kg); estradiol (E, 5 μg/kg); E + EEtOH-Cl; tamoxifen (T, 4mg/kg). This extract presented estrogenic activity by increasing the relative weight (%) of the uterus of rats treated at doses of 125, 250 and 500 mg/kg (0.267 ± 0.016*, 0.231 ± 0.014*, 0.242 ± 0.015*), and it showed anti-estrogenic activity when associated with estradiol (0.116 ± 0.006*, 0.103 ± 0.06*, 0.098 ± 0.05*), respectively. For assessment of toxicity in pregnancy, the animals were divided into two groups and treated daily with EEtOH-Cl. In the first group, the effect of the extract on the development of pregnancy from first to seventh day was observed, and in the second group, from 8 to 21 days, there was no change of these parameters or the viability of the progeny when the study assessed reproductive and foetal toxicity; however, there was shortening of pregnancy (125 mg/kg) without affecting the progeny. In the in vitro study, uterine strips of pregnant (P) and non-pregnant (NP) females were used. In both groups, half received EEtOH-Cl (vo) for 13 days (treated females - T), and the other half received EEtOH-Cl directly to the isolated organ bath system (untreated - NT). In vitro study on the uterus of pregnant animals pretreated with doses of 250 and 500 mg/kg showed that there was inhibition of KCl 80-induced phasic contractions (0.490 ± 0.110, 0.540 ± 0.092), respectively. Also, the contractions induced by oxytocin were inhibited at a dose of 500 mg/kg (0.380 ± 0.109). In non-pregnant, non-treated females, the extract at a concentration of 125 μg/mL (0.180 ± 0.062) also inhibited the contractions induced by oxytocin. Thus, EEtOH-Cl demonstrated estrogenic activity, but when combined with estradiol, it demonstrated anti-estrogenic activity. It did not induce toxicity in the progenitors or in the progeny, and it inhibited isometric contractions induced by oxytocin and KCl 80 mM in pregnant and non-pregnant rats.Keywords: Copaifera luetzelburgii, (anti-)estrogenicity, reproductive toxicity, phasic contractionsAfrican Journal of Biotechnology Vol. 12(24), pp. 3864-387

Alzheimer's Disease: a Review of its Visual System Neuropathology. Optical Coherence Tomography-a Potential Role As a Study Tool in Vivo

Alzheimer's disease (AD) is a prevalent, long-term progressive degenerative disorder with great social impact. It is currently thought that, in addition to neurodegeneration, vascular changes also play a role in the pathophysiology of the disease. Visual symptoms are frequent and are an early clinical manifestation; a number of psychophysiologic changes occur in visual function, including visual field defects, abnormal contrast sensitivity, abnormalities in color vision, depth perception deficits, and motion detection abnormalities. These visual changes were initially believed to be solely due to neurodegeneration in the posterior visual pathway. However, evidence from pathology studies in both animal models of AD and humans has demonstrated that neurodegeneration also takes place in the anterior visual pathway, with involvement of the retinal ganglion cells' (RGCs) dendrites, somata, and axons in the optic nerve. These studies additionally showed that patients with AD have changes in retinal and choroidal microvasculature. Pathology findings have been corroborated in in-vivo assessment of the retina and optic nerve head (ONH), as well as the retinal and choroidal vasculature. Optical coherence tomography (OCT) in particular has shown great utility in the assessment of these changes, and it may become a useful tool for early detection and monitoring disease progression in AD. The authors make a review of the current understanding of retinal and choroidal pathological changes in patients with AD, with particular focus on in-vivo evidence of retinal and choroidal neurodegenerative and microvascular changes using OCT technology.info:eu-repo/semantics/publishedVersio

Perfil microbiológico da carne de frangos abatidos artesanalmente e na indústria, comercializados na grande Recife-PE

Considerando o elevado consumo da carne de frango no contexto nacional e mais especificamente na cidade do Recife, onde o abate clandestino ainda é intenso, objetivou-se delinear o perfil microbiológico da carne de frango disponível no mercado, comparando-se os produtos advindos de abatedouro industrial e artesanal e verificar se os produtos atendiam às especificações dos padrões recomendados pela legislação. Determinou-se o Número Mais Provável (NMP) de coliformes totais e termotolerantes, bem como realizou-se a pesquisa de Salmonella spp. e Aeromonas spp., além da contagem de bactérias aeróbias mesófilas, psicrófilas e Staphylococcus spp.. Foram analisadas 24 amostras, sendo que 12 advindas do processamento de frigoríficos industriais, resfriadas e comercializadas. As outras 12 amostras foram provenientes de abatedouro artesanal e comercializadas sem refrigeração. Nos resultados obtidos, a contagem de Staphylococcus spp., a determinação do NMP de coliformes totais e termotolerantes apresentaram valores acima dos permitidos nas carcaças artesanais, enquanto que, as pesquisas de Salmonella spp. e Aeromonas spp. não apresentaram diferença significativa. Nas carcaças artesanais o número de bactérias mesófilas foi 2,6 vezes maior que nas industriais, enquanto que no número de psicrófilas/pisicotróficas não houve diferença significativa entre as amostras. Algumas amostras não estão dentro dos padrões recomendados pela legislação

Operation and performance of the ATLAS Tile Calorimeter in Run 1

The Tile Calorimeter is the hadron calorimeter covering the central region of the ATLAS experiment at the Large Hadron Collider. Approximately 10,000 photomultipliers collect light from scintillating tiles acting as the active material sandwiched between slabs of steel absorber. This paper gives an overview of the calorimeter’s performance during the years 2008–2012 using cosmic-ray muon events and proton–proton collision data at centre-of-mass energies of 7 and 8TeV with a total integrated luminosity of nearly 30 fb−1. The signal reconstruction methods, calibration systems as well as the detector operation status are presented. The energy and time calibration methods performed excellently, resulting in good stability of the calorimeter response under varying conditions during the LHC Run 1. Finally, the Tile Calorimeter response to isolated muons and hadrons as well as to jets from proton–proton collisions is presented. The results demonstrate excellent performance in accord with specifications mentioned in the Technical Design Report

Treinamento de força e seus efeitos sobre a área de secção transversa e perímetro celular de miócitos do gastrocnêmio de Rattus novergicus

O treinamento de força é uma das modalidades de exercício físico mais praticadas na atualidade. O objetivo do presente estudo foi comparar a área e o perímetro de miócitos do gastrocnêmio de ratos (Rattus novergicus) submetidos a um protocolo crônico de 25 sessões de treinamento de força. Os resultados indicaram aumento da área e do perímetro celular do grupo treinado, em relação ao grupo controle (não treinado). A hipertrofia celular promove aumento da força e manutenção neuromuscular de maneira positiva. Conclui-se que o treinamento de força é uma alternativa não medicamentosa que promove o aumento de força, verificado pela hipertrofia muscular, e pode auxiliar no tratamento de diversas doenças que carecem desta valência física. ABSTRACT Strength training and its effects on the cross-section área and mobile perimeter of rattus novergicus gastrocnemioStrenght training is one of the most popular choices of physical conditioning training nowadays. The objective of the current study was to compare the area and the perimiter of rats’ (Rattus novergicus) gastrocnemius miocytes, submitted to a chronical 25 strenght training sessions. The results indicate increasing of the cell area and perimeter on the experimental group when compared to the control gruoup (not trained at all during the study). The cell hypertrophy promotes raising of the muscle strenght and nerumuscular maintaince in a positive way. It is conclued that the stenght training is a non-phamacological alternative that promotes muscular strenght raising, verified by the muscular hypertrophy, and can help on the treatment of several diseases that need this physical variable