Avaliação da morfologia testicular e dos parâmetros espermáticos em ratos espontaneamente hipertensos e tratados com enalapril

A hipertensão arterial sistêmica (HAS) é um problema de saúde pública, geralmente associada a outras doenças, como obesidade, diabetes, doença renal, aterosclerose, acidente vascular cerebral (AVC) e identificado como um dos fatores de risco mais prevalentes para o desenvolvimento de doenças cardiovasculares. Orgãos-alvo, como coração, rins, cérebro e olhos, são comumente afetados em pacientes hipertensos. No entanto, o dano testicular causado pela hipertensão não foi claramente definido. A hipertensão é um fator de risco bem estabelecido para a disfunção erétil, mas sua relação com o dano testicular e a fertilidade masculina não é claramente compreendida. Este estudo avalia a morfologia testicular e alguns parâmetros espermáticos de ratos espontaneamente hipertensos (SHR), virgem de tratamento e tratados com enalapril. Ratos SHR foram distribuídos em dois grupos, um grupo hipertenso (H), e um grupo tratado com enalapril (HE). Ratos Wistar-Kyoto (WKY) foram utilizados como controles. A pressão arterial sistólica foi medida semanalmente, até o final do experimento. A concentração de espermatozóides, motilidade e viabilidade foram determinadas em amostras coletadas da cauda do epidídimo. Métodos estereológicos foram usados para analisar objetivamente a morfologia testicular macroscopicamente e microscopicamente. Todos os dados foram analisados por ANOVA com pós-teste de Tukey, considerando p <0,05. Ao final do experimento a pressão arterial sistólica no grupo HE (153,9 mmHg 21,03 ) foi semelhante a dos animais pertencentes ao grupo WKY (153,4 24,41) e menor que a dos animais H (205,1 24,9). A concentração espermática do grupo H (1,31 x 107 sptz/ml 0,27) foi inferior à do grupo WKY (2,11 x 107 sptz/ml 0,34), entretanto o controle da pressão arterial com o enalapril melhorou este parâmetro e a concentração espermática do grupo HE (2,46 x 107 sptz/ml 0,54) foi semelhante a do WKY. A densidade volumétrica vascular também foi alterada no grupo de hipertensos, enquanto que os animais do grupo HE foram semelhantes aos controles. O epitélio seminífero dos animais HE apresentou a maior densidade volumétrica, indicando um possível efeito protetor indireto do enalapril na espermatogênese. Neste modelo animal, a HAS promoveu alterações morfológicas no testículo, com conseqüências sobre a produção de espermatozóides. O controle da pressão arterial com o enalapril protegeu o testículo destas alterações, restabelecendo a produção normal dos espermatozóides.

Efeito do extrato de Euterpe oleracea Mart.(Açaí) sobre a disfunção endotelial, estresse oxidativo e alterações vasculares e renais associados à hipertensão renovascular dois rins, 1 clip (2R,1C)

Estudos recentes mostram que o açaí é rico em polifenóis e uma dieta rica em polifenóis pode estar envolvida na proteção contra o risco cardiovascular. O objetivo deste estudo foi avaliar o efeito do tratamento crônico de animais hipertensos 2R,1C com extrato hidroalcoólico do caroço do açaí (ASE) sobre o desenvolvimento da hipertensão e disfunção endotelial; estresse oxidativo e sobre as alterações vasculares e renais. Ratos Wistar machos foram utilizados para obtenção da hipertensão renovascular 2R,1C e ratos controles 2R (sham) foram somente submetidos à laparotomia e receberam tratamento diário com veículo ou ASE (200 mg/Kg/dia) durante 40 dias. A pressão arterial sistólica (PAS) foi aferida por pletismografia de cauda e os efeitos vasodilatadores da acetilcolina (ACh) e nitroglicerina (NG) foram estudados em leito arterial mesentérico (LAM) perfundido e pré-contraído com norepinefrina. A atividade das enzimas SOD, CAT, GPx, os níveis de MDA, a carbonilação de proteínas e os níveis de nitrito foram avaliados por espectrofotometria. As expressões de enzimas pró e antioxidantes foram avaliadas por western blot. A atividade de MMP-2 foi avaliada por zimografia. Os níveis séricos de creatinina foram avaliados através de kit, por espectrofotometria. As alterações vasculares e renais foram avaliadas por microscopia de luz. A PAS foi maior nos animais 2R,1C, e o tratamento com ASE preveniu o desenvolvimento da hipertensão. O efeito vasodilatador reduzido da ACh em animais 2R,1C foi recuperado pelo ASE. O efeito vasodilatador da NG não foi diferente entre os grupos. O dano oxidativo avaliado pela peroxidação lipídica e carbonilação de proteínas foi maior nos animais 2R,1C, e reduzido pelo tratamento com ASE. As atividades da SOD, CAT e GPx foram menores em amostras de mesentério, plasma, rim e coração de animais 2R,1C e o tratamento com ASE aumentou estas atividades. A produção de NO foi menor no plasma, mesentério e rim dos animais 2R,1C, e o tratamento com ASE aumentou a produção de NO somente no rim e mesentério destes animais. A expressão de SOD-1, 2, eNOS e TIMP-1 foram menores nos animais 2R,1C e o tratamento com ASE aumentou a expressão destas enzimas. A expressão de NOX-4 e MMP-2 e a atividade de MMP-2 foram maiores nos animais 2R,1C e o tratamento com ASE reduziu a expressão destas enzimas e a atividade de MMP-2. Os animais 2R,1C apresentaram um aumento na espessura da camada média da aorta e artéria mesentérica e um aumento na relação média/lúmen da aorta, e estas alterações foram prevenidas pelo ASE. Os níveis séricos aumentados de creatinina nos animais 2R,1C foram reduzidos por ASE. As alterações morfológicas renais nos animais 2R,1C foram prevenidas pelo ASE. Portanto, o tratamento com ASE previne o desenvolvimento da hipertensão, melhora a disfunção endotelial e previne as alterações vasculares e renais em ratos 2R,1C. A redução da atividade antioxidante e o aumento na peroxidação lipídica e carbonilação de proteínas sugerem o envolvimento de um mecanismo deficiente da defesa antioxidante e de um dano oxidativo aumentado, os quais foram revertidos pelo ASE.

In vivo study on the effects of microcystin extracts on the expression profiles of proto-oncogenes (c-fos, c-jun and c-myc) in liver, kidney and testis of male Wistar rats injected i.v. with toxins

Microcystins (MCs) are a potent liver tumor promoter, possessing potent tumor-promoting activity and weak initiating activity. Proto-oncogenes are known to be involved in the tumor-promoting mechanisms of microcystin-LR. However, few data are available on the effects of MCs oil proto-oncogenes in the whole animal. To investigate the effects of MCs on the expression profile of the proto-oncogenes in different organs, male Wistar rats were injected intravenously with microcystin extracts at a dose of 86.7 mu g MC-LR eq/kg bw (MC-LR eq, MC-LR equivalents). mRNA levels of three proto-oncogenes c-fos, c-jun and c-myc in liver, kidney and testis were analyzed using quantitative real-time PCR at several time points post-injection. Significant induction of these genes at transcriptional level was observed in the three organs. In addition, the increase of mRNA expression of all three genes was much higher in liver than in kidney and testis. Meanwhile, the protein levels of c-Fos and c-Jun were investigated by western blotting. Both proteins were induced in the three organs. However, elevations of protein levels were Much lower than those of mRNA levels. These findings suggest that the expression of c-fos, c-jun and c-myc might be one possible mechanism for the tumor-promoting activity and initiating activity of microcystins. (c) 2008 Published by Elsevier Ltd.

Gene structure of an antimicrobial peptide from mandarin fish, Siniperca chuatsi (Basilewsky), suggests that moronecidins and pleurocidins belong in one family: the piscidins

The gene of piscidin, an antimicrobial peptide, has been cloned from the mandarin fish, Siniperca chuatsi. From the first transcription initiation site, the mandarin fish piscidin gene extends 1693 nucleotides to the end of the 3' untranslated region and contains four exons and three introns. A predicted 79-residue prepropeptide consists of three domains: a signal peptide (22 aa), a mature peptide (22 aa) and a C-terminal prodomain (35 aa). The shortage of XQQ motif in the prodomain of mandarin fish piscidin and the similar gene structure between moronecidins (piscidins) and pleurocidins may indicate that they are derived from the same ancestor gene. We thus suggest that piscidin should be used as a terminology for these antimicrobial peptides in the future. The mandarin fish piscidin mRNA was abundant in intestine, spleen, pronephros and kidney analysed by real-time polymerase chain reaction. After stimulation with lipopoly saccharides (LPS), a marked increase in transcripts was observed in most tissues, indicating that piscidin is not only a constitutively expressed molecule, but also has an increased response to bacterial infection. The synthetic, amidated mandarin fish piscidin exhibited different antimicrobial activity against different fish bacterial pathogens, especially against species of Aeromonas, which may to certain extent reflect the pathogenicity of these bacteria.

Insuficiência renal crónica e infeções associadas aos diferentes tratamentos

Projeto de Pós-Graduação/Dissertação apresentado à Universidade Fernando Pessoa como parte dos requisitos para obtenção do grau de Mestre em Ciências Farmacêuticas

Vascular calcification and mineral bone disorder in chronic kidney disease

Chronic Kidney Disease (CKD), osteoporosis and mild hyponatremia are all prevalent chronic conditions that may coexist and are often under-recognized. Mineral-Bone Disorder begins early in the natural history of CKD and results in complex abnormalities of bone which ultimately confers a well-established increased risk of fragility fractures in End Stage Kidney Disease. Hyponatremia is a novel, usually renal mediated metabolic perturbation, that most commonly occurs independently of the stage of renal dysfunction but which may also predispose to increased fracture risk. The extent -if any- to which either early stages of renal dysfunction or the presence of hyponatremia contribute to fracture occurrence in the general population, independently of osteoporosis, is unclear. Renal transplantation is the treatment of choice for ESKD and although it restores endogenous renal function it typically fails to normalize either the long term cardiovascular or fracture risk. One potential mechanism contributing to these elevated long-term risks and to diminished Health Related Quality of Life is persistent, post-transplant hyperparathyroidism. In this study we retrospectively examine the association of renal function and serum sodium with Bone Mineral Density and fracture occurrence in a retrospective cohort of 1930 female members of the general population who underwent routine DXA scan. We then prospectively recruited a cohort of 90 renal transplant recipients in order to examine the association of post transplant parathyroid hormone (PTH) level with measures of CKD Mineral Bone Disorder, including, DXA Bone Mineral Density, Vascular Calcification (assessed using both abdominal radiography and CT techniques, as well as indirectly by carotid-femoral Pulse Wave Velocity) and Quality of Life (using the Short Form-12 and a PTH specific symptom score). In the retrospective DXA cohort, moderate CKD (eGFR 30-59ml/min/1.73m2) and hyponatremia (<135mmol/L) were associated with fracture occurrence, independently of BMD, with an adjusted Odds Ratio (95% Confidence Interval), of 1.37 (1.0, 1.89) and 2.25 (1.24, 4.09) respectively. In the renal transplant study, PTH was independently associated with the presence of osteoporosis, adjusted Odds Ratio (95% Confidence Interval), 1.15 (per 10ng/ml increment), (1.04, 1.26). The presence of osteoporosis but not PTH was independently associated with measures of vascular calcification, adjusted ß (95% Confidence Interval), 12.45, (1.16, 23.75). Of the eight quality-of-life domains examined, post-transplant PTH (per 10ng/ml increment), was only significantly and independently associated with reduced Physical Functioning, (95% Confidence Interval), 1.12 (1.01, 1.23). CKD and hyponatremia are both common health problems that may contribute to fracture occurrence in the general population, a major on-going public health concern. PTH and decreased Bone Mineral Density may signal sub-optimal long-term outcomes post renal transplantation, influencing bone and vascular health and to a limited extent long term Health Related Quality of Life

Renal failure and the neural control of the kidney

Renal failure (RF) is associated with an over activation of the sympathetic nervous system. The aim of this thesis was to investigate the hypothesis that as the kidney progresses into RF there is an inappropriate and sustained activation of renal afferent nerves which results in a dysregulation of basal RSNA and reflexly controlled RSNA by the high and low pressure baroreceptors. Baroreflex gain curves for both RSNA and HR were generated in control and RF rats. This study clearly showed a blunted high-pressure baroreflex in RF rats, an impairment which was almost completely corrected by bilateral renal denervation. The integrity of the low-pressure cardiopulmonary receptors to inhibit RSNA was investigated using acute saline volume. Again, a blunted reflex sympatho-inhibition of RSNA was observed, which was corrected by renal denervation. Finally a functional study to examine how the renal excretory response to volume expansion differed in RF was carried out. This study revealed an impairment of the low-pressure baroreflex control of the sympathetic outflow. The result of these studies suggest that cisplatin induced RF initiates a neural signal from within the kidney, which over rides the normal reflex regulation of RSNA by the high and low – pressure baroreceptors and that this impairment in function can be normalised by renal denervation. This raises further questions as to the mechanisms involved in the afferent over activation arising from the diseased kidneys.

Large decrease of anti-tetanus anatoxin and anti-pneumococcal antibodies at one year after renal transplantation.

Aims: In kidney transplant recipients (KTR), antibody (Ab) synthesis is hampered by AZA and CsA. We here report in a prospective cohort study, the effects of mycophenolate mofetil (MMF) associated to a calcineurin inhibitor on plasma levels of anti-tetanus anatoxin Ab (TAnAb) and anti-pneumococcal Ab (PnPsAb). Methods: Serum titers of the TAnAb and the PnPsAb against serotypes 14, 19F and 23F were measured in 94 KTR on Day 0 (T0) and 1 year (T12) after renal transplantation and in 49 healthy controls. Results: 1) At T0, TAnAb were detected in only 71% of patients vs. 98% of controls (p < 0.0001) and the titers were significantly lower in KTR (1.46 UI/ml vs. 2.74 in controls, p = 0.01); they further decreased between T0 and T12 (1.46 UI/ml to 0.31, p < 0.0001). The calculated half-life (t1/2) of TAnAb was 7.7 months, as compared to more than 10 years in a normal population. 2) In KTR, PnPsAb titers decreased significantly between T0 and T12 (p < 0.005); the t1/2 of the different PnPsAb ranged from 9.2 to 11.9 months. Conclusions: In KTR treated by MMF and CNI, the TAnAbs and PnPsAbs titers decrease significantly and profoundly during the first year. Immunization pre-transplantation should be encouraged to maintain adequate post-transplant Abs levels.

Interleukin-15 receptor blockade in non-human primate kidney transplantation.

BACKGROUND: Interleukin (IL)-15 is a chemotactic factor to T cells. It induces proliferation and promotes survival of activated T cells. IL-15 receptor blockade in mouse cardiac and islet allotransplant models has led to long-term engraftment and a regulatory T-cell environment. This study investigated the efficacy of IL-15 receptor blockade using Mut-IL-15/Fc in an outbred non-human primate model of renal allotransplantation. METHODS: Male cynomolgus macaque donor-recipient pairs were selected based on ABO typing, major histocompatibility complex class I typing, and carboxy-fluorescein diacetate succinimidyl ester-based mixed lymphocyte responses. Once animals were assigned to one of six treatment groups, they underwent renal transplantation and bilateral native nephrectomy. Serum creatinine level was monitored twice weekly and as indicated, and protocol biopsies were performed. Rejection was defined as a increase in serum creatinine to 1.5 mg/dL or higher and was confirmed histologically. Complete blood counts and flow cytometric analyses were performed periodically posttransplant; pharmacokinetic parameters of Mut-IL-15/Fc were assessed. RESULTS: Compared with control animals, Mut-IL-15/Fc-treated animals did not demonstrate increased graft survival despite adequate serum levels of Mut-IL-15/Fc. Flow cytometric analysis of white blood cell subgroups demonstrated a decrease in CD8 T-cell and natural killer cell numbers, although this did not reach statistical significance. Interestingly, two animals receiving Mut-IL-15/Fc developed infectious complications, but no infection was seen in control animals. Renal pathology varied widely. CONCLUSIONS: Peritransplant IL-15 receptor blockade does not prolong allograft survival in non-human primate renal transplantation; however, it reduces the number of CD8 T cells and natural killer cells in the peripheral blood.

Nurse-led behavioral management of diabetes and hypertension in community practices: a randomized trial.

BACKGROUND: Several trials have demonstrated the efficacy of nurse telephone case management for diabetes (DM) and hypertension (HTN) in academic or vertically integrated systems. Little is known about the real-world potency of these interventions. OBJECTIVE: To assess the effectiveness of nurse behavioral management of DM and HTN in community practices among patients with both diseases. DESIGN: The study was designed as a patient-level randomized controlled trial. PARTICIPANTS: Participants included adult patients with both type 2 DM and HTN who were receiving care at one of nine community fee-for-service practices. Subjects were required to have inadequately controlled DM (hemoglobin A1c [A1c] ≥ 7.5%) but could have well-controlled HTN. INTERVENTIONS: All patients received a call from a nurse experienced in DM and HTN management once every two months over a period of two years, for a total of 12 calls. Intervention patients received tailored DM- and HTN- focused behavioral content; control patients received non-tailored, non-interactive information regarding health issues unrelated to DM and HTN (e.g., skin cancer prevention). MAIN OUTCOMES AND MEASURES: Systolic blood pressure (SBP) and A1c were co-primary outcomes, measured at 6, 12, and 24 months; 24 months was the primary time point. RESULTS: Three hundred seventy-seven subjects were enrolled; 193 were randomized to intervention, 184 to control. Subjects were 55% female and 50% white; the mean baseline A1c was 9.1% (SD = 1%) and mean SBP was 142 mmHg (SD = 20). Eighty-two percent of scheduled interviews were conducted; 69% of intervention patients and 70% of control patients reached the 24-month time point. Expressing model estimated differences as (intervention--control), at 24 months, intervention patients had similar A1c [diff = 0.1 %, 95 % CI (-0.3, 0.5), p = 0.51] and SBP [diff = -0.9 mmHg, 95% CI (-5.4, 3.5), p = 0.68] values compared to control patients. Likewise, DBP (diff = 0.4 mmHg, p = 0.76), weight (diff = 0.3 kg, p = 0.80), and physical activity levels (diff = 153 MET-min/week, p = 0.41) were similar between control and intervention patients. Results were also similar at the 6- and 12-month time points. CONCLUSIONS: In nine community fee-for-service practices, telephonic nurse case management did not lead to improvement in A1c or SBP. Gains seen in telephonic behavioral self-management interventions in optimal settings may not translate to the wider range of primary care settings.

The Dietary Approaches to Stop Hypertension (DASH) eating pattern in special populations.

The Dietary Approaches to Stop Hypertension (DASH) trial showed that a diet rich in fruits, vegetables, low-fat dairy products with reduced total and saturated fat, cholesterol, and sugar-sweetened products effectively lowers blood pressure in individuals with prehypertension and stage I hypertension. Limited evidence is available on the safety and efficacy of the DASH eating pattern in special patient populations that were excluded from the trial. Caution should be exercised before initiating the DASH diet in patients with chronic kidney disease, chronic liver disease, and those who are prescribed renin-angiotensin-aldosterone system antagonist, but these conditions are not strict contraindications to DASH. Modifications to the DASH diet may be necessary to facilitate its use in patients with chronic heart failure, uncontrolled diabetes mellitus type II, lactose intolerance, and celiac disease. In general, the DASH diet can be adopted by most patient populations and initiated simultaneously with medication therapy and other lifestyle interventions.

Two Cases of Late Shone Syndrome With Pulmonary Hypertension: Heart-Lung Transplant or Valve Surgery?

Two cases of Shone syndrome with severe mitral and aortic valve problems and pulmonary hypertension were referred for heart-lung transplantation. Severely elevated pulmonary vascular resistance (PVR) was confirmed as was severe periprosthetic mitral and aortic regurgitation. Based on the severity of the valve lesions in both patients, surgery was decided upon and undertaken. Both experienced early pulmonary hypertensive crises, one more than the other, that gradually subsided, followed by excellent recovery and reversal of pulmonary hypertension and PVR. These cases illustrate Braunwald's concept that pulmonary hypertension secondary to left-sided valve disease is reversible.

Hypertension - a contemporary approach to nursing care

The incidence of hypertension is increasing as the number of patients with obesity and diabetes mellitus increases. Hypertension results when the peripheral vascular resistance is increased, the blood viscosity is elevated and/or the flow of blood through the main arteries is impeded. Chronic hypertension results in enlarged heart, myocardial damage and lung and renal abnormalities. While some causative factors such as obesity can be controlled, others for example genetics are more difficult to treat because often there is more than one factor involved. This paper explores how essential and secondary factors contribute to the incidence of hypertension and the physiological changes resulting from raised blood pressure. It proposes that although traditional treatment has some success, nurse-led clinics are having better success not only in controlling raised blood pressure but also in reducing cardiac, pulmonary and renal morbidity. It is more cost-effective, staff is more productive and clients are more compliant with treatment.

Differential expression of components of the cardiomyocyte adrenomedullin/intermedin receptor system following blood pressure reduction in nitric oxide-deficient hypertension.

Adrenomedullin (AM) and intermedin (IMD; adrenomedulln-2) are vasodilator peptides related to calcitonin gene-related peptide (CGRP). The actions of these peptides are mediated by the calcitonin receptor-like receptor (CLR) in association with one of three receptor activity-modifying proteins. CGRP is selective for CLR/receptor activity modifying protein (RAMP)1, AM for CLR/RAMP2 and -3, and IMD acts at both CGRP and AM receptors. In a model of pressure overload induced by inhibition of nitric-oxide synthase, up-regulation of AM was observed previously in cardiomyocytes demonstrating a hypertrophic phenotype. The current objective was to examine the effects of blood pressure reduction on cardiomyocyte expression of AM and IMD and their receptor components. Nomega-nitro-L-arginine methyl ester (L-NAME) (35 mg/kg/day) was administered to rats for 8 weeks, with or without concurrent administration of hydralazine (50 mg/kg/day) and hydrochlorothiazide (7.5 mg/kg/day). In left ventricular cardiomyocytes from L-NAME-treated rats, increases (-fold) in mRNA expression were 1.6 (preproAM), 8.4 (preproIMD), 3.4 (CLR), 4.1 (RAMP1), 2.8 (RAMP2), and 4.4 (RAMP3). Hydralazine/hydrochlorothiazide normalized systolic blood pressure (BP) and abolished mRNA up-regulation of hypertrophic markers sk-alpha-actin and BNP and of preproAM, CLR, RAMP2, and RAMP3 but did not normalize cardiomyocyte width nor preproIMD or RAMP1 mRNA expression. The robust increase in IMD expression indicates an important role for this peptide in the cardiac pathology of this model but, unlike AM, IMD is not associated with pressure overload upon the myocardium. The concordance of IMD and RAMP1 up-regulation indicates a CGRP-type receptor action; considering also a lack of response to BP reduction, IMD may, like CGRP, have an anti-ischemic function.

Development of a rapid screening test for veterinary sedatives and the beta-blocker carazolol in porcine kidney by ELISA

Sedatives and tranquillisers are frequently used to reduce stress during the transportation of food producing animals. The most widely used classes of sedatives include the butyrophenone azaperone, the phenothiazines acepromazine, propionylpromazine, chlorpromazine and the beta-blocker, carazolol. For regulatory control purposes, tolerances for azaperone and carazolol have been set by the European Union as 100 and 25 mug kg(-1), respectively. Furthermore, the use of the phenothiazines is prohibited and therefore has a zero tolerance. A method for the detection of residues of five tranquillisers and one beta-blocker using a single ELISA plate has been developed. Kidney samples (2.5 g) were extracted with dichloromethane and applied to a competitive enzyme immunoassay using three polyclonal antibodies raised in rabbits against azaperol, propionylpromazine and carazolol conjugates. In sample matrix, the azaperol antibody cross-reacted 28.0% with azaperone and the propionylpromazine antibody cross-reacted 24.9% with acepromazine and 11.7% with chlorpromazine. In the ELISA, the detection capabilities of the six sedatives, azaperol, azaperone, carazolol, acepromazine, chlorpromazine, and propionylpromazine are 5, 15, 5, 5, 20 and 5 mug kg(-1), respectively. The proposed method is a sensitive and rapid multi-residue technique that offers a cost effective alternative to current published procedures, without any concession on the ability to detect sedative misuse.