The effect of ovariectomy on cardiac autonomic control in rats submitted to aerobic physical training

We have investigated the ovariectomy effects on the cardiovascular autonomic adaptations induced by aerobic physical training and the role played by nitric oxide (NO). Female Wistar rats (n =70) were divided into five groups: Sedentary Sham (SS): Trained Sham (TS); Trained Hypertensive Sham treated with N(C)-nitro-L-arginine methyl ester (L-NAME) (THS): Trained Ovariectomized (TO); and Trained Hypertensive Ovariectomized treated with L-NAME (THO). Trained groups were submitted to a physical training during 10 weeks. The cardiovascular autonomic control was investigated in all groups using different approaches: 1) pharmacological evaluation of autonomic tonus with methylatropine and propranolol; 2) analysis of heart rate (HR) and systolic arterial pressure (AP) variability; 3) spontaneous baroreflex sensitivity (BRS) evaluation. Hypertension was observed in THS and THO groups. Pharmacological analysis showed that TS group had increased predominance of autonomic vagal tonus compared to SS group. HR and intrinsic HR were found to be reduced in all trained animals. TS group, compared to other groups, showed a reduction in LF oscillations (LF=0.2-0.75 Hz) of pulse interval in both absolute and normalized units as well as an increase in HF oscillations (HF=0.75-2.50 Hz) in normalized unit. FIRS analysis showed that alpha-index was different between all groups. TS group presented the greatest value, followed by the TO, SS. THO and THS groups. Ovariectomy has negative effects on cardiac autonomic modulation in trained rats, which is characterized by an increase in the sympathetic autonomic modulation. These negative effects suggest NO deficiency. In contrast, the ovariectomy seems to have no effect on AP variability. (C) 2008 Elsevier B.V. All rights reserved.

Inhibition of COX 1 and 2 prior to Renal Ischemia/Reperfusion Injury Decreases the Development of Fibrosis

Ischemia and reperfusion injury (IRI) contributes to the development of chronic interstitial fibrosis/tubular atrophy in renal allograft patients, Cyclooxygenase (COX) 1 and 2 actively participate in acute ischemic injury by activating endothelial cells and inducing oxidative stress. Furthermore, blockade of COX I and 2 has been associated with organ improvement after ischemic damage. The aim of this study was to evaluate the role of COX I and 2 in the development of fibrosis by performing a COX I and 2 blockade immediately before IRI We subjected C57BI/6 male mice to 60 min of unilateral renal pedicle occlusion, Prior to surgery mice were either treated with indomethacin (IMT) at days -1 and 0 or were untreated. Blood and kidney samples were collected 6 wks after IRI. Kidney samples were analyzed by real-time reverse transcription-poly me rase chain reaction for expression of transforming growth factor beta (TGF-beta), monocyte chemoattractant protein 1 (MCP-1), osteopontin (OPN), tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-1 beta, IL-10, heme oxygenose 1 (HO-1), vimentin, connective-tissue growth factor (CTGF), collagen 1, and bone morphogenic protein 7 (BMP-7), To assess tissue fibrosis we performed morphometric analyses and Sirius red staining. We also performed immunohistochemical analysis of anti-actin smooth muscle, Renal function did not significantly differ between groups. Animals pretreated with IMT showed significantly less interstitial fibrosis than nontreated animals. Gene transcript analyses showed decreased expression of TGF-beta, MCP-1,TNF-alpha, IL-1-beta, vimentin, collagen 1, CTGF and IL-10 mRNA (all P < 0.05), Moreover, HO-I mRNA was increased in animals pretreated with IMT (P < 0.05) Conversely, IMT treatment decreased osteopontin expression and enhanced BMP-7 expression, although these levels did rot reach statistical significance when compared with control expression levels, I he blockade of COX 1 and 2 resulted in less tissue fibrosis, which was associated with a decrease in proinflammatory cytokines and enhancement of the protective cellular response.

Insights on calcium-independent phospholipid membrane damage by Lys49-PLA(2) using tryptophan scanning mutagenesis of bothropstoxin-I from Bothrops jararacussu

Bothropstoxin-I (BthTx-I) is a homodimerie Lys49-PLA(2) from the venom of the snake Bothrops jararacussu, which lacks hydrolytic activity against phospholipid substrates, yet permeabilizes membranes by a Ca2+- independent mechanism. The interaction of the BthTx-I with model membranes has been studied by intrinsic tryptophan fluorescence emission (ITFE) spectroscopy. Nine separate mutants have been created each with a unique tryptophan residue located at a different position in the interfacial recognition site (IRS) of the protein. The rapid and efficient Ca2+-independent membrane damage against unilamellar liposomes composed of DPPC/DMPA in a 9:1 molar ratio was unaffected by these substitutions. Binding studies revealed low protein affinity for these liposomes and no changes were observed in the ITFE properties. In contrast, the binding of all mutants to DPPC/DMPA liposomes in a 1:1 molar ratio was stronger, and was correlated with altered ITFE properties. The blue-shifted emission spectra and increased emission intensity of mutants at positions 31, 67 and 115-117 in the interface recognition surface of the protein suggest these regions are partially inserted into the membrane. These results are consistent with a model for the Ca2+-independent membrane damaging mechanism that involves a transient interaction of the protein with the outer phospholipid leaflet of the target membrane. (C) 2007 Elsevier Masson SAS. All rights reserved.

Oleic acid modulation of the immune response in wound healing: A new approach for skin repair

Injury triggers inflammatory responses and tissue repair. Several treatments are currently in use to accelerate healing: however, more efficient formulations are still needed for specific injuries. Since unsaturated fatty acids modulate immune responses, we aimed to evaluate their therapeutic effects on wound healing. Skin wounds were induced in BALB/c mice and treated for 5 days with n-3, n-9 fatty acids or vehicle (control). n-9 treated mice presented smaller wounds than control and n-3 at 120 h post-surgery (p.s.). Collagen III mRNA,TIMP1 and MMP9 were significantly elevated in n-9 group compared to n-3 or vehicle at 120 h p.s. Among the inflammatory mediators studied we found that IL-10, TNF-alpha and IL-17 were also higher in n-9 treated group compared to n-3 or vehicle at 120 h p.s. Interestingly, COX2 had decreased expression on wound tissue treated with n-9. Inflammatory infiltrate analysis revealed diminished frequency of CD4(+), CD8(+) and CD11b(+) cells in n-9 wounds at 24 and 120 h p.s., which was not related to cell death, since in vitro apoptosis experiments did not show any cell damage after fatty acids administration. These results suggested that unsaturated fatty acids, specifically n-9, modulate the inflammation in the wound and enhance reparative response in vivo. n-9 may be a useful tool in the treatment of cutaneous wounds. (C) 2010 Elsevier GmbH. All rights reserved.

Effect of isoflavone extracts from Glycine max on human endothelial cell damage and on nitric oxide production

Objective: In this study, we determined the protective effect of isoflavones from Glycine max on human umbilical vein endothelial cell (ECV304) damage induced by hydrogen peroxide (H(2)O(2)) and on nitric oxide (NO) production. Methods: We studied the regulation of NO synthesis in cultured human endothelial cells by phytoestrogens contained in soy extracts in the presence or absence of ICI 182,780 or N(omega)-nitro-L-arginine methyl esther and determined the protective effect of these isoflavones on ECV304 damage induced by H(2)O(2). Results: We show that soy extracts activate NO synthesis in endothelial cells and protect against cell damage. Conclusions: In conclusion, soy isoflavones markedly protect ECV304 cells against H(2)O(2) damage and promote NO synthesizing. Therefore, these isoflavones call potentially act as an NO promoter and as an antioxidant.

Serum cardiac troponin I concentration in dogs with ehrlichiosis

Background: Ehrlichiosis is a multisystemic disease with the potential to cause cardiomyocyte injury in naturally infected dogs. Hypothesis: Myocardial injury occurs in dogs infected with Ehrlichia canis. Animals: One-hundred and ninety-four dogs from Brazil with clinical and laboratory abnormalities indicative of ehrlichiosis. Sixteen healthy dogs served as controls. Methods: Electrocardiogram, echocardiogram, noninvasive blood pressure measurement, and serum cardiac troponin I (cTnI) concentrations were evaluated. Serologic assays and PCR determined the exposure and infection status for E. canis, Anaplasma spp., Babesia canis vogeli, Bartonella spp., Borrelia burgdorferi, Dirofilaria immitis, Ehrlichia chaffeensis, Ehrlichia ewingii, Leishmania chagasi, and spotted-fever group Rickettsia. Dogs were assigned to groups according to PCR status: E. canis infected, infected with other vector-borne organisms, sick dogs lacking PCR evidence for infection, and healthy controls. Results: E. canis-infected dogs had higher serum cTnI concentrations than controls (median: 0.04 ng/dL; range 0.04-9.12 ng/dL; control median: 0.04 ng/dL; range: 0.04-0.10 ng/dL; P = .012), and acute E. canis infection was associated with myocardial injury (odds ratio [OR]: 2.67, confidence interval [CI] 95%: 1.12-6.40, P = .027). Severity of anemia was correlated with increased risk of cardiomyocyte damage (r = 0.84, P < .001). Dogs with clinical signs of systemic inflammatory response syndrome (SIRS) were at higher risk for myocardial injury than were other sick dogs (OR: 2.55, CI 95%: 1.31-4.95, P = .005). Conclusions and Clinical Importance: Acute infection with E. canis is a risk factor for myocardial injury in naturally infected Brazilian dogs. Severity of anemia and SIRS might contribute to the pathophysiology of myocardial damage.

Temporal evolution of epithelial, vascular and interstitial lung injury in an experimental model of idiopathic pulmonary fibrosis induced by butyl-hydroxytoluene

This study was undertaken to test whether the structural remodelling of pulmonary parenchyma can be sequentially altered in a model and method that demonstrate the progression of the disease and result in remodelling within the lungs that is typical of idiopathic pulmonary fibrosis. Three groups of mice were studied: (i) animals that received 3-5-di-tert-butyl-4-hydroxytoluene (BHT) and were killed after 2 weeks (early BHT = 9); (ii) animals that received BHT and were killed after 4 weeks (late BHT = 11); (iii) animals that received corn oil solution (control = 10). The mice were placed in a ventilated Plexiglas chamber with a mixture of pure humidified oxygen and compressed air. Lung histological sections underwent haematoxylin-eosin, immunohistochemistry (epithelial, endothelial and immune cells) and specific staining (collagen/elastic fibres) methods for morphometric analysis. When compared with the control group, early BHT and late BHT groups showed significant decrease of type II pneumocytes, lower vascular density in both and higher endothelial activity. CD4 was increased in late BHT compared with early and control groups, while CD8, macrophage and neutrophil cells were more prominent only in early BHT. The collagenous fibre density were significantly higher only in late BHT, whereas elastic fibre content in late BHT was lower than that in control group. We conclude that the BHT experimental model is pathologically very similar to human usual interstitial pneumonia. This feature is important in the identification of animal models of idiopathic pulmonary fibrosis that can accurately reflect the pathogenesis and progression of the human disease.

Multiplex semi-nested RT-PCR with exogenous internal control for simultaneous detection of bovine coronavirus and group A rotavirus

Neonatal calf diarrhea is a multi-etiology syndrome of cattle and direct detection of the two major agents of the syndrome, group A rotavirus and Bovine coronavirus (BCoV) is hampered by their fastidious growth in cell culture. This study aimed at developing a multiplex semi-nested RT-PCR for simultaneous detection of BCoV (N gene) and group A rotavirus (VP1 gene) with the addition of an internal control (mRNA ND5). The assay was tested in 75 bovine feces samples tested previously for rotavirus using PAGE and for BCoV using nested RT-PCR targeted to RdRp gene. Agreement with reference tests was optimal for BCoV (kappa = 0.833) and substantial for rotavirus detection (kappa = 0.648). the internal control, ND5 mRNA, was detected successfully in all reactions. Results demonstrated that this multiplex semi-nested RT-PCR was effective in the detection of BCoV and rotavirus, with high sensitivity and specificity for simultaneous detection of both viruses at a lower cost, providing an important tool for studies on the etiology of diarrhea in cattle. (C) 2010 Elsevier B.V. All rights reserved.

Dynamics and Control of Stray Dog Populations

The population dynamics of stray dogs is simulated to assess the effects of sterilization and euthanasia. From simulations representing less than 5 years, sterilization is less efficient than euthanasia to reduce the stray dog population, considering similar rates, but the total number of sterilized dogs is less than the total number of euthanized dogs per km(2) per year. Over 20 years, both strategies have similar efficiency. Beyond a certain rate of dog abandonment, both strategies are inefficient.

Protective efficacy of bacterial membranes containing surface-exposed BM95 antigenic peptides for the control of cattle tick infestations

The Rhipicephalus (Boophilus) microplus BM86 and BM95 glycoproteins are homologous proteins that protect cattle against tick infestations. In this study, we demonstrated that the recombinant chimeric protein comprising tick BM95 immunogenic peptides fused to the A. marginale MSP1a N-terminal region for presentation on the Escherichia coli membrane was protective against R. microplus infestations in rabbits. This system provides a novel and simple approach for the production of tick protective antigens by surface display of antigenic protein chimera on live E. coli and suggests the possibility of using recombinant bacterial membrane fractions for vaccination against cattle tick infestations. (C) 2009 Elsevier Ltd. All rights reserved.

Evaluation of DNA damage by the alkaline comet assay of the olfactory and respiratory epithelia of dogs from the city of Sao Paulo, Brazil

Animals kept as pets may be considered sentinels for environmental factors to which humans could be exposed. Olfactory and respiratory epithelia are directly subjected to airborne factors, which could cause DNA lesions, and the alkaline comet assay is considered a reliable tool for the assessment of DNA damage. The objective of this work is to evaluate the extent of DNA damage by the comet assay of the olfactory and respiratory epithelia of dogs from different regions of the city of sao Paulo, Brazil. Thirty-three clinically healthy dogs, aged 5 years or more, were used in the study, with 7 from the North region of Sao Paulo, 7 from the South region, 3 dogs from the East region, and 16 dogs from the West city region. Three dogs younger than 6 months were used as controls. DNA damage was analyzed by the alkaline comet assay. We observed no difference in histopathological analysis of olfactory and respiratory epithelia between dogs from different regions of Sao Paulo. Dogs older than 5 years presented significantly higher comet length in both olfactory and respiratory epithelia, when compared with controls, indicating DNA damage. When separated by regions, olfactory and respiratory epithelia presented similar DNA damage in dogs from different regions of Sao Paulo, corroborating with similar levels of particulate matter index (PM10) in all regions of the city. In this study, we report for the first time that the comet assay can be used to quantify the extent of DNA damage in dog olfactory and respiratory epithelia, and that comet length (DNA damage) increases with age, probably due to environmental factors. Air pollution, as measured by PM 10, can be responsible for this DNA damage. (C) 2009 Elsevier GmbH. All rights reserved.

Pfaffia paniculata (Brazilian ginseng) roots decrease proliferation and increase apoptosis but do not affect cell communication in murine hepatocarcinogenesis

Pfaffia paniculata (Brazilian ginseng) roots and/or its extracts have shown anti-neoplastic, chemopreventive, and anti-angiogenic properties. The aim of this work was to investigate the chemopreventive mechanisms of this root in Mice Submitted to the infant model of hepatocarcinogenesis, evaluating the effects oil cellular proliferation, apoptosis. and intercellular communication. Fifteen-day-old BALB/c male mice were given, i.p., 10 mu g/g of the carcinogen N-nitrosodiethylamine (DEN). Animals were separated into three groups at weaning and were given different concentrations of powdered P. paniculata root (0%, 2%, or 10%) added to commercial food for 27 weeks. Control group (CT) was not exposed to the carcinogen and was given ration without the root. After euthanasia, the animals` liver and body weight were measured. Liver fragments were sampled to Study intercellular communication, molecular biology, and histopathological analysis. Cellular proliferation was evaluated by immunohistochemistry for PCNA, apoptosis was evaluated by apoptotic bodies count and alkaline cornet technique, and inter-cellular communication by diffusion of lucifer yellow dye, immunofluorescence, western blot and real-time PCR for connexins 26 and 32. Chronic treatment with powdered P. paniculata root reduced cellular proliferation and increased apoptosis in the 2%, group. Animals in the 10% group had an increase in apoptosis with chronic inflammatory process. Intercellular communication showed no alterations in any of the groups analyzed. These results Indicate that chemopreventive effects of P. paniculata are related to the control of cellular proliferation and apoptosis, but not to cell communication and/or connexin expression, and are directly Influenced by the root concentration. (C) 2009 Elsevier GmbH. All rights reserved.

Protective action of indole-3-acetic acid on induced hepatocarcinoma in mice

In this study, we report the protective effects of IAA on diethylnitrosamine (DEN)-induced hepatocarcinogenesis. BALB/c mice received daily IAA at 50 (T(50)), 250 (T(250)), and 500 (T(500)) mg K(-1) per body mass by gavage for 15 days. At day 15, animals were administered DEN and sacrificed 4 h later. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were analyzed in sera. In addition., hepatomorphologic alterations, activity of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione reductase (GR), gene expression of antioxidant enzymes and DNA integrity were evaluated in the liver. IAA administration did not show any alterations in any of the parameters available, except for a reduction of the gene expression for antioxidant enzyrries by 55, 56, 27, and 28% for SOD, CAT, GPx, and GR upon T(500). respectively compared with the control. Several hepatic alterations were observed by DEN exposure. Moreover, IAA administration at 3 doses was shown to provide a total prevention of the active reduction of CAT and GR induced by DEN exposure compared with the control. IAA at T5(00) was shown to give partial protection (87, 71, 57, and 90% for respectively SOD, CAT. GPx. and GR) on the down-regulation of the enzymes induced by DEN and this auxin showed a partial protection (50%) on DEN-induced DNA fragmentation for both parameters when compared to DEN alone. This work showed IAA hepatocarcinogenesis protection for the first time by means of a DEN-protective effect on CAT and GR activity. and by affecting antioxidant gene expression and DNA fragmentation. Copyright (C) 2008 John Wiley & Sons, Ltd.