RESUMEN
OBJECTIVE: Renal ischaemia reperfusion injury (IRI) is inevitable during open repair of pararenal aortic aneurysms. Pre-operative fasting potently increases resistance against IRI. The effect of fasting on IRI was examined in a hypomorphic Fibulin-4 mouse model (Fibulin-4+/R), which is predisposed to develop aortic aneurysms. METHODS: Wild type (WT) and Fibulin-4+/R mice were either fed ad libitum (AL) or fasted for two days before renal IRI induction by temporary clamping of the renal artery and vein of both kidneys. Six hours, 48 h, and seven days post-operatively, serum urea levels, renal histology, and mRNA expression levels of inflammatory and injury genes were determined to assess kidney function and damage. Additionally, matrix metalloproteinase activity in the kidney was assessed six months after IRI. RESULTS: Two days of fasting improved survival the first week after renal IRI in WT mice compared with AL fed mice. Short term AL fed Fibulin-4+/R mice showed improved survival and kidney function compared with AL fed WT mice, which could not be further enhanced by fasting. Both fasted WT and Fibulin-4+/R mice showed improved survival, kidney function and morphology compared with AL fed mice six months after renal IRI. Fibulin-4+/R kidneys of fasted mice showed reduced apoptosis together with increased matrix metalloprotease activity levels compared with AL fed Fibulin-4+/R mice, indicative of increased matrix remodelling. CONCLUSION: Fibulin-4+/R mice are naturally protected against the short-term, but not long-term, consequences of renal IRI. Pre-operative fasting protects against renal IRI and prevents (long-term) deterioration of kidney function and morphology in both WT and Fibulin-4+/R mice. These data suggest that pre-operative fasting may decrease renal damage in patients undergoing open abdominal aneurysm repair.
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Aneurisma de la Aorta/cirugía , Ayuno , Metaloproteinasas de la Matriz/metabolismo , Insuficiencia Renal Crónica/prevención & control , Daño por Reperfusión/complicaciones , Animales , Aneurisma de la Aorta/genética , Apoptosis , Peso Corporal , Modelos Animales de Enfermedad , Proteínas de la Matriz Extracelular/genética , Receptor Celular 1 del Virus de la Hepatitis A/genética , Interleucina-6/genética , Riñón/metabolismo , Riñón/patología , Riñón/fisiopatología , Masculino , Ratones , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Periodo Preoperatorio , ARN Mensajero/metabolismo , Insuficiencia Renal Crónica/etiología , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/patología , Tasa de Supervivencia , Factores de Tiempo , Urea/sangreRESUMEN
Somatic gain-of-function mutations of GNAQ and GNA11, which encode α subunits of heterotrimeric Gαq/11 proteins, occur in about 85% of cases of uveal melanoma (UM), the most common cancer of the adult eye. Molecular therapies to directly target these oncoproteins are lacking, and current treatment options rely on radiation, surgery, or inhibition of effector molecules downstream of these G proteins. A hallmark feature of oncogenic Gαq/11 proteins is their reduced intrinsic rate of hydrolysis of guanosine triphosphate (GTP), which results in their accumulation in the GTP-bound, active state. Here, we report that the cyclic depsipeptide FR900359 (FR) directly interacted with GTPase-deficient Gαq/11 proteins and preferentially inhibited mitogenic ERK signaling rather than canonical phospholipase Cß (PLCß) signaling driven by these oncogenes. Thereby, FR suppressed the proliferation of melanoma cells in culture and inhibited the growth of Gαq-driven UM mouse xenografts in vivo. In contrast, FR did not affect tumor growth when xenografts carried mutated B-RafV600E as the oncogenic driver. Because FR enabled suppression of malignant traits in cancer cells that are driven by activating mutations at codon 209 in Gαq/11 proteins, we envision that similar approaches could be taken to blunt the signaling of non-Gαq/11 G proteins.
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Depsipéptidos/farmacología , Sistemas de Liberación de Medicamentos , Subunidades alfa de la Proteína de Unión al GTP Gq-G11 , Subunidades alfa de la Proteína de Unión al GTP , Mutación con Ganancia de Función , Melanoma , Proteínas de Neoplasias , Neoplasias de la Úvea , Animales , Línea Celular Tumoral , Depsipéptidos/química , Subunidades alfa de la Proteína de Unión al GTP/antagonistas & inhibidores , Subunidades alfa de la Proteína de Unión al GTP/genética , Subunidades alfa de la Proteína de Unión al GTP/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/antagonistas & inhibidores , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/genética , Subunidades alfa de la Proteína de Unión al GTP Gq-G11/metabolismo , Células HEK293 , Humanos , Melanoma/tratamiento farmacológico , Melanoma/enzimología , Melanoma/genética , Melanoma/patología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Neoplasias de la Úvea/tratamiento farmacológico , Neoplasias de la Úvea/enzimología , Neoplasias de la Úvea/genética , Neoplasias de la Úvea/patología , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Caloric restriction increases lifespan and healthspan, and limits age-associated muscle wasting. In this study, we investigate the impact of 30% caloric restriction (CR) in a murine cancer cachexia model. Forty CD2F1 mice were allocated as C26 tumor-bearing (TB) + ad libitum food intake (dietary reference intake [DRI]), TB CR, non-TB (NTB) CR, or NTB matched intake (MI). TB groups were inoculated subcutaneously with 0.5x106 C26 cells 14 days after initiating CR. Bodyweight, food intake, and grip-strength were recorded periodically. Gastrocnemius (GCM) and tibialis anterior (TA) muscles were resected and weighed 3 weeks after tumor inoculation. mRNA expression of MuRF1, Atrogin-1, myogenin, and MyoD was determined. At tumor inoculation, the mean body weight of TB CR was 88.6% of initial body weight and remained stable until sacrifice. TB DRI showed wasting before sacrifice. TB groups experienced muscle wasting compared with NTB MI. Grip-strength change was less severe in TB CR. Expression of MuRF1, Atrogin-1, and MyoD was similar between TB DRI and both CR groups. Expression of myogenin was increased in CR groups. In conclusion, caloric restriction limits loss of muscle strength but has no impact on muscle mass despite significant loss of body weight in an experimental cancer-associated cachexia model.
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Caquexia/etiología , Caquexia/prevención & control , Restricción Calórica , Neoplasias Experimentales/complicaciones , Animales , Ingestión de Alimentos , Masculino , Ratones , Fuerza Muscular , Atrofia MuscularRESUMEN
The parathyroid hormone receptor 1 (PTH1R) is a member of family B of G-protein-coupled receptors (GPCRs), predominantly expressed in bone and kidney where it modulates extracellular Ca2+ homeostasis and bone turnover. It is well established that phosphorylation of GPCRs constitutes a key event in regulating receptor function by promoting arrestin recruitment and coupling to G-protein-independent signaling pathways. Mapping phosphorylation sites on PTH1R would provide insights into how phosphorylation at specific sites regulates cell signaling responses and also open the possibility of developing therapeutic agents that could target specific receptor functions. Here, we have used mass spectrometry to identify nine sites of phosphorylation in the C-terminal tail of PTH1R. Mutational analysis revealed identified two clusters of serine and threonine residues (Ser489-Ser495 and Ser501-Thr506) specifically responsible for the majority of PTH(1-34)-induced receptor phosphorylation. Mutation of these residues to alanine did not affect negatively on the ability of the receptor to couple to G-proteins or activate extracellular-signal-regulated kinase 1/2. Using fluorescence resonance energy transfer and bioluminescence resonance energy transfer to monitor PTH(1-34)-induced interaction of PTH1R with arrestin3, we show that the first cluster Ser489-Ser495 and the second cluster Ser501-Thr506 operated in concert to mediate both the efficacy and potency of ligand-induced arrestin3 recruitment. We further demonstrate that Ser503 and Thr504 in the second cluster are responsible for 70% of arrestin3 recruitment and are key determinants for interaction of arrestin with the receptor. Our data are consistent with the hypothesis that the pattern of C-terminal tail phosphorylation on PTH1R may determine the signaling outcome following receptor activation.
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Receptor de Hormona Paratiroídea Tipo 1/metabolismo , Secuencia de Aminoácidos , Arrestinas/metabolismo , Transferencia de Energía por Resonancia de Bioluminiscencia , Ensayo de Inmunoadsorción Enzimática , Transferencia Resonante de Energía de Fluorescencia , Células HEK293 , Humanos , Inmunoprecipitación , Espectrometría de Masas , Datos de Secuencia Molecular , Fosforilación , Receptor de Hormona Paratiroídea Tipo 1/química , Receptores Acoplados a Proteínas G/metabolismo , Homología de Secuencia de Aminoácido , Transducción de SeñalRESUMEN
Mesenchymal stem cells (MSC) are studied as a cell therapeutic agent for treatment of various immune diseases. However, therapy with living culture-expanded cells comes with safety concerns. Furthermore, development of effective MSC immunotherapy is hampered by lack of knowledge of the mechanisms of action and the therapeutic components of MSC. Such knowledge allows better identification of diseases that are responsive to MSC treatment, optimization of the MSC product, and development of therapy based on functional components of MSC. To close in on the components that carry the therapeutic immunomodulatory activity of MSC, we generated MSC that were unable to respond to inflammatory signals or secrete immunomodulatory factors, but preserved their cellular integrity [heat-inactivated MSC (HI-MSC)]. Secretome-deficient HI-MSC and control MSC showed the same biodistribution and persistence after infusion in mice with ischemic kidney injury. Both control and HI-MSC induced mild inflammatory responses in healthy mice and dramatic increases in interleukin-10, and reductions in interferon gamma levels in sepsis mice. In vitro experiments showed that opposite to control MSC, HI-MSC lacked the capability to suppress T-cell proliferation or induce regulatory B-cell formation. However, both HI-MSC and control MSC modulated monocyte function in response to lipopolysaccharides. The results of this study demonstrate that, in particular disease models, the immunomodulatory effect of MSC does not depend on their secretome or active cross-talk with immune cells, but on recognition of MSC by monocytic cells. These findings provide a new view on MSC-induced immunomodulation and help identify key components of the therapeutic effects of MSC.
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Inmunomodulación , Células Madre Mesenquimatosas/inmunología , Animales , Linfocitos B/citología , Movimiento Celular , Proliferación Celular , Citocinas/metabolismo , Modelos Animales de Enfermedad , Femenino , Humanos , Inmunofenotipificación , Inflamación/patología , Infusiones Intravenosas , Lipopolisacáridos , Masculino , Células Madre Mesenquimatosas/citología , Ratones Endogámicos C57BL , Monocitos/citología , Sepsis/inmunología , Sepsis/patología , Linfocitos T/citología , Distribución TisularRESUMEN
BACKGROUND: Liver transplantation (LT) is the only life-saving treatment for patients with end-stage liver disease. The increase in patients has prompted the use of not only donation after brain death (DBD) donors but also living donors (LD) and donation after cardiac death (DCD) donors. Donor-type affects early graft function and graft survival as evidenced by an increased risk of developing ischemic type biliary lesions and higher risk of graft loss in DCD as compared with those in DBD grafts. METHODS: Using a rat model, we used quantitative reverse transcription-polymerase chain reaction to examine expression levels of proinflammatory, cytoprotective, and injury genes and determined apoptosis in DCD and DBD livers at different time points after retrieval. RESULTS: After retrieval, early mediators of inflammation MCP-1, HMGB1, and toll-like receptor (TLR 4) were increased in DCD livers, whereas the proinflammatory genes interleukin 6, interleukin 1ß, tumor necrosis factor alpha, P-selectin, and E-selectin were massively upregulated in DBD compared with those in LD livers. HO-1 was increased in both postmortem groups. After cold ischemia, DCD livers showed increased levels of MCP-1, TLR4, and HMGB1, whereas expression of proinflammatory genes in DBD liver remained high. During 12 h of cold storage, expression levels remained stable except Hif-1α and HMGB1. DCD showed higher number of apoptotic cells compared with DBD livers. CONCLUSIONS: Compared with LD, DCD livers showed only mild upregulation of inflammatory markers, but increased levels of MCP-1, HMGB1, and TLR4, and more apoptotic cells. In contrast, DBD livers showed a massive inflammatory response. These differences in tissue injury and inflammatory response might be relevant for the outcome after LT.
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Muerte Encefálica/inmunología , Citocinas/genética , Muerte , Mediadores de Inflamación/metabolismo , Hígado/inmunología , Donantes de Tejidos , Transcriptoma , Animales , Apoptosis , Quimiocina CCL2/genética , Proteína HMGB1/genética , Hemo Oxigenasa (Desciclizante)/genética , Masculino , Ratas , Ratas Endogámicas BN , Receptor Toll-Like 4/genética , Factor A de Crecimiento Endotelial Vascular/genéticaRESUMEN
Ischemia-reperfusion injury (IRI) is inevitable during kidney transplantation leading to oxidative stress and inflammation. We previously reported that preoperative fasting in young-lean male mice protects against IRI. Since patients are generally of older age with morbidities possibly leading to a different response to fasting, we investigated the effects of preoperative fasting on renal IRI in aged-overweight male and female mice. Male and female F1-FVB/C57BL6-hybrid mice, average age 73 weeks weighing 47.2 grams, were randomized to preoperative ad libitum feeding or 3 days fasting, followed by renal IRI. Body weight, kidney function and survival of the animals were monitored until day 28 postoperatively. Kidney histopathology was scored for all animals and gene expression profiles after fasting were analyzed in kidneys of young and aged male mice. Preoperative fasting significantly improved survival after renal IRI in both sexes compared with normal fed mice. Fasted groups had a better kidney function shown by lower serum urea levels after renal IRI. Histopathology showed less acute tubular necrosis and more regeneration in kidneys from fasted mice. A mRNA analysis indicated the involvement of metabolic processes including fatty acid oxidation and retinol metabolism, and the NRF2-mediated stress response. Similar to young-lean, healthy male mice, preoperative fasting protects against renal IRI in aged-overweight mice of both genders. These findings suggest a general protective response of fasting against renal IRI regardless of age, gender, body weight and genetic background. Therefore, fasting could be a non-invasive intervention inducing increased oxidative stress resistance in older and overweight patients as well.
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Ayuno , Trasplante de Riñón/efectos adversos , Riñón/patología , Daño por Reperfusión/prevención & control , Factores de Edad , Animales , Nitrógeno de la Urea Sanguínea , Femenino , Masculino , Redes y Vías Metabólicas , Ratones , Ratones Endogámicos C57BL , Sobrepeso , Estrés OxidativoRESUMEN
BACKGROUND: The superior long-term survival of kidneys from living donors (LDs) compared with kidneys from donation-after-brain-death (DBD) and donation-after-cardiac-death (DCD) donors is now well established. However, comparative studies on transcriptional changes that occur at organ retrieval and during and after cold ischemia (CI) are sparse. METHODS: Using a rat model, we used qRT-PCR to examine expression levels of inflammatory, cytoprotective, and injury genes at different time points after organ retrieval. Cleaved caspase-3 was used to evaluate early apoptosis in DCD and DBD kidneys. RESULTS: Immediately after retrieval, we found massive up-regulation of proinflammatory genes interleukin-1ß, interleukin-6, tumor necrosis factor-α, monocyte chemotactic protein-1, P-selectin, and E-selectin in DBD compared with LD and DCD kidneys. A significant increase in the expression of injury markers Kim-1, p21, and the cytoprotective gene heme oxygenase-1 accompanied this. Bax was increased in DCD kidneys, and Bcl-2 was decreased in DBD kidneys. After 2 hr of CI in the LD group and 18 hr in the DBD and DCD groups, gene expression levels were similar to those found after retrieval. During 18 hr of cold storage, expression levels of these genes did not change. In DCD and DBD kidneys, early apoptosis increased after CI. DISCUSSION/CONCLUSION: The gene expression profile in DBD kidneys represents an inflammatory and injury response to brain death. In contrast, DCD kidneys show only mild up-regulation of inflammatory and injury genes. These results may imply why delayed graft function in DCD kidneys does not have the deleterious effect it has on DBD kidneys.
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Lesión Renal Aguda/genética , Muerte Encefálica/metabolismo , Perfilación de la Expresión Génica , Inflamación/genética , Riñón/metabolismo , Lesión Renal Aguda/inmunología , Lesión Renal Aguda/metabolismo , Lesión Renal Aguda/patología , Animales , Apoptosis , Muerte Encefálica/inmunología , Muerte Encefálica/patología , Isquemia Fría , Citoprotección , Funcionamiento Retardado del Injerto/genética , Funcionamiento Retardado del Injerto/inmunología , Funcionamiento Retardado del Injerto/metabolismo , Funcionamiento Retardado del Injerto/patología , Perfilación de la Expresión Génica/métodos , Regulación de la Expresión Génica , Marcadores Genéticos , Inflamación/inmunología , Inflamación/metabolismo , Inflamación/patología , Mediadores de Inflamación/metabolismo , Riñón/inmunología , Riñón/patología , Trasplante de Riñón/efectos adversos , Masculino , Modelos Animales , Preservación de Órganos , Ratas , Ratas Endogámicas BN , Factores de Riesgo , Factores de Tiempo , Transcripción GenéticaRESUMEN
The core defining features of bulimia nervosa (BN) are repeated binge eating episodes and inappropriate compensatory (e.g., purging) behavior. Previous studies suggest an abnormal post-prandial response in the satiety-signaling peptide cholecystokinin (CCK) in persons with BN. It is unknown whether this altered response persists following remission or if it may be a potential target for the development of clinical treatment strategies. To examine the nature of this altered response, this study assessed whether CCK normalizes following remission from BN (RBN). This study prospectively evaluated the plasma CCK response and corresponding eating behavior-related ratings (e.g., satiety, fullness, hunger, urge to binge and vomit) in individuals with BN-purging subtype (n=10), RBN-purging subtype (n=14), and healthy controls (CON, n=13) at baseline, +15, +30, and +60 min following the ingestion of a standardized liquid test meal. Subject groups did not significantly differ in CCK response to the test meal. A significant relationship between CCK response and satiety ratings was observed in the RBN group (r=.59, p<.05 two-tailed). A new and unanticipated finding in the BN group was a significant relationship between CCK response and ratings of "urge to vomit" (r=.86, p<.01, two-tailed). Unlike previous investigations, CCK response did not differ in BN and CON groups. Thus the role of symptom severity remains an area of further investigation. Additionally, findings suggest that in this sample, CCK functioning following remission from BN-purging subtype is not different from controls. It remains unknown whether or not CCK functioning may be a protective or liability factor in the stabilization and recovery process. Replication studies utilizing a larger sample size are needed to further elucidate the role of CCK in recovery from BN and its potential target of related novel treatment strategies.
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Bulimia Nerviosa/sangre , Bulimia/sangre , Colecistoquinina/sangre , Ingestión de Alimentos/fisiología , Hambre/fisiología , Saciedad/fisiología , Adolescente , Adulto , Femenino , Humanos , Persona de Mediana Edad , Periodo Posprandial/fisiología , Estudios ProspectivosRESUMEN
We reported previously that the robust protection against renal ischemia/reperfusion (I/R) injury in mice by fasting was largely initiated before the induction of renal I/R. In addition, we found that preoperative fasting downregulated the gene expression levels of complexes I, IV, and V of the mitochondrial oxidative phosphorylation (OXPHOS) system, while it did not change those of complexes II and III. Hence, we now investigated the effect of 3 days of fasting on the functioning of renal mitochondria in order to better understand our previous findings. Fasting did not affect mitochondrial density. Surprisingly, fasting significantly increased the protein expression of complex II of the mitochondrial OXPHOS system by 19%. Complex II-driven state 3 respiratory activity was significantly reduced by fasting (46%), which could be partially attributed to the significant decrease in the enzyme activity of complex II (16%). Fasting significantly inhibited Ca(2+) -dependent mitochondrial permeability transition pore opening that is directly linked to protection against renal I/R injury. The inhibition of the mitochondrial permeability transition pore did not involve the expression of the voltage-dependent anion channel by fasting. In conclusion, 3 days of fasting clearly induces the inhibition of complex II-driven mitochondrial respiration state 3 in part by decreasing the amount of functional complex II, and inhibits mitochondrial permeability transition pore opening. This might be a relevant sequence of events that could contribute to the protection of the kidney against I/R injury.
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Complejo II de Transporte de Electrones/genética , Ayuno , Mitocondrias/metabolismo , Proteínas de Transporte de Membrana Mitocondrial/genética , Periodo Preoperatorio , Animales , Complejo II de Transporte de Electrones/metabolismo , Expresión Génica , Humanos , Riñón/lesiones , Riñón/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Mitocondrias/genética , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Poro de Transición de la Permeabilidad Mitocondrial , Fosforilación Oxidativa , Daño por Reperfusión/genética , Daño por Reperfusión/metabolismo , Daño por Reperfusión/prevención & control , Canales Aniónicos Dependientes del Voltaje/genética , Canales Aniónicos Dependientes del Voltaje/metabolismoRESUMEN
BACKGROUND: Preoperative fasting induces robust protection against renal ischemia/reperfusion (I/R) injury in mice but is considered overcautious and possibly detrimental for postoperative recovery in humans. Furthermore, fasting seems to conflict with reported benefits of preoperative nutritional enhancement with carbohydrate-rich drinks. Here, we investigated whether preoperative ingestion of a glucose solution interferes with fasting-induced protection against renal I/R injury. METHODS: Mice were randomized into the following groups: fasted for 3 days with access to water (fasted) or a glucose solution (fasted+glc) and fed ad libitum with water (fed) or a glucose solution (fed+glc). After induction of bilateral renal I/R injury, all animals had free access to food and water. Calorie intake, body weight, insulin sensitivity, kidney function, and animal survival were determined. RESULTS: Fed+glc mice had a comparable daily calorie intake as fed mice, but 50% of those calories were obtained from the glucose solution. Fasted+glc mice had a daily calorie intake of approximately 75% of the intake of both fed groups. This largely prevented the substantial body weight loss seen in fasted animals. Preoperative insulin sensitivity was significantly improved in fasted+glc mice versus fed mice. After I/R injury, kidney function and animal survival were superior in both fasted groups. CONCLUSIONS: The benefits of fasting and preoperative nutritional enhancement with carbohydrates are not mutually exclusive and may be a clinically feasible regimen to protect against renal I/R injury.
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Ayuno/fisiología , Glucosa/farmacología , Riñón/fisiopatología , Periodo Preoperatorio , Daño por Reperfusión/prevención & control , Administración Oral , Animales , Peso Corporal/efectos de los fármacos , Ingestión de Energía/efectos de los fármacos , Glucosa/administración & dosificación , Resistencia a la Insulina/fisiología , Riñón/irrigación sanguínea , Riñón/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Modelos Animales , Flujo Sanguíneo Regional/fisiología , Daño por Reperfusión/fisiopatología , Factores de TiempoRESUMEN
PURPOSE: The Joint Commission established a new safety goal mandating staff education in evidence-based infection prevention due to multidrug-resistant organisms (MDROs). This pilot study assessed the effectiveness of the MDRO educational module in our behavioral health hospital. DESIGN AND METHODS: An online survey was administered to a convenience sample (N= 44) consisting of employees hired within the previous 8 months. FINDINGS: Results identified knowledge gaps between and among disciplines that guided subsequent improvements to our MDRO educational module. PRACTICE IMPLICATIONS: Online surveys are an effective way to evaluate knowledge gaps and may be useful in other educational activities within nursing.
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Infección Hospitalaria/prevención & control , Resistencia a Múltiples Medicamentos , Hospitales Psiquiátricos , Investigación en Evaluación de Enfermería , Enfermería Psiquiátrica/educación , Encuestas de Atención de la Salud/métodos , Conocimientos, Actitudes y Práctica en Salud , Hospitales con 100 a 299 Camas , Humanos , Evaluación de Necesidades , Proyectos PilotoRESUMEN
We show that brief periods of fasting induce functional changes similar to those induced by long-term dietary restriction in mice, and these changes include protection from ischemia/reperfusion (I/R) injury. In this study, we investigated the mechanisms of protection induced by fasting, and we determined the effect on liver regeneration after partial hepatectomy. Partial hepatic ischemia (75 minutes) was induced in ad libitum fed mice and in 1- to 3-day-fasted mice, and one-third or two-thirds hepatectomy was performed in ad libitum fed mice and 3-day-fasted mice. Preoperative fasting for 2 or 3 days significantly decreased hepatocellular I/R injury. Hepatic gene expression of heme oxygenase 1 (HO-1), superoxide dismutase 2 (SOD2), glutathione peroxidase 1 (Gpx1), and glutathione reductase (GSR) was significantly up-regulated in 3-day-fasted mice at the baseline and 6 hours after reperfusion. After reperfusion, p-selectin and interleukin-6 (IL-6) levels were significantly lower, and superoxide radical generation, lipid peroxidation, and neutrophil influx were significantly attenuated in 3-day-fasted mice. Preoperative fasting did not affect liver regeneration after one-third hepatectomy. Hepatic gene expression of IL-6 and transforming growth factor ß1 was significantly higher in 3-day-fasted mice before and after one-third hepatectomy. Tumor necrosis factor α expression significantly increased after one-third hepatectomy in 3-day-fasted mice. After a 3-day fast and two-thirds hepatectomy, liver regeneration and subsequent postoperative recovery were compromised. In conclusion, up-regulation of the stress response gene HO-1 and the antioxidant enzymes SOD2, Gpx1, and GSR at the baseline and a better response after reperfusion likely underlie the protection induced by fasting against hepatic I/R injury. Preoperative fasting may be a promising new strategy for protecting the liver against I/R injury during liver transplantation and minor liver resections, although its effect on extended hepatectomy warrants further exploration.
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Ayuno/fisiología , Regeneración Hepática/fisiología , Hígado/lesiones , Hígado/fisiopatología , Periodo Preoperatorio , Daño por Reperfusión/prevención & control , Daño por Reperfusión/fisiopatología , Animales , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Hemo-Oxigenasa 1/metabolismo , Hepatectomía , Interleucina-6/metabolismo , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Modelos Animales , Daño por Reperfusión/metabolismo , Superóxido Dismutasa/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Regulación hacia Arriba/fisiología , Glutatión Peroxidasa GPX1RESUMEN
Dietary restriction (DR) extends lifespan and increases resistance to multiple forms of stress, including ischemia reperfusion injury to the brain and heart in rodents. While maximal effects on lifespan require long-term restriction, the kinetics of onset of benefits against acute stress is not known. Here, we show that 2-4 weeks of 30% DR improved survival and kidney function following renal ischemia reperfusion injury in mice. Brief periods of water-only fasting were similarly effective at protecting against ischemic damage. Significant protection occurred within 1 day, persisted for several days beyond the fasting period and extended to another organ, the liver. Protection by both short-term DR and fasting correlated with improved insulin sensitivity, increased expression of markers of antioxidant defense and reduced expression of markers of inflammation and insulin/insulin-like growth factor-1 signaling. Unbiased transcriptional profiling of kidneys from mice subject to short-term DR or fasting revealed a significant enrichment of signature genes of long-term DR. These data demonstrate that brief periods of reduced food intake, including short-term daily restriction and fasting, can increase resistance to ischemia reperfusion injury in rodents and suggest a rapid onset of benefits of DR in mammals.
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Restricción Calórica , Ayuno , Enfermedades Renales/dietoterapia , Daño por Reperfusión/dietoterapia , Animales , Regulación de la Expresión Génica , Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Enfermedades Renales/genética , Enfermedades Renales/metabolismo , Enfermedades Renales/fisiopatología , Pruebas de Función Renal , Masculino , Ratones , Ratones Endogámicos C57BL , Análisis de Secuencia por Matrices de Oligonucleótidos , Daño por Reperfusión/genética , Daño por Reperfusión/metabolismo , Daño por Reperfusión/fisiopatología , Transducción de Señal , Tasa de Supervivencia , Factores de Tiempo , Transcripción GenéticaRESUMEN
BACKGROUND: We have previously reported that small synthetic oligopeptides related to human beta-chorionic gonadotropin (beta-hCG) can reduce inflammation. Here we investigated whether such oligopeptides can reduce renal ischaemia-reperfusion injury in the mouse. METHODS: Ten different oligopeptides were administered 1 min before induction of renal ischaemia and 1 min before reperfusion. RESULTS: Survival at 72 h post-reperfusion was significantly higher in mice treated with oligopeptides MTRV, LQG, VLPALPQ or AQGV as compared to placebo-treated mice. Some oligopeptides were more effective than others. AQGV completely prevented mortality and best preserved kidney function. Next, AQGV was tested in a dose-escalating study in a range of 0.3-30 mg/kg. A survival gain was observed with all doses. Improvement of kidney function was observed from 1 mg/kg. Highest survival and best preserved kidney function were observed at 3 and 10 mg/kg. Upon treatment with AQGV, a significantly lower influx of neutrophils was found, apoptosis was decreased, whereas tubular epithelial cell proliferation was significantly increased at 24 h post-reperfusion. Serum levels of TNF-alpha, INF-gamma, IL-6 and IL-10 were significantly decreased at 24 h post-reperfusion. E-selectin mRNA levels in kidneys were significantly decreased at 6 h post-reperfusion. AQGV did not reduce mortality when treatment was started after reperfusion. CONCLUSIONS: This study shows that small oligopeptides related to the primary structure of beta-hCG, especially AQGV, are promising potential drugs for preventing the development of renal ischaemia-reperfusion injury.
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Gonadotropina Coriónica Humana de Subunidad beta/farmacología , Riñón/efectos de los fármacos , Riñón/lesiones , Oligopéptidos/farmacología , Daño por Reperfusión/prevención & control , Secuencia de Aminoácidos , Animales , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Gonadotropina Coriónica Humana de Subunidad beta/química , Gonadotropina Coriónica Humana de Subunidad beta/genética , Citocinas/sangre , Citocinas/genética , Relación Dosis-Respuesta a Droga , Humanos , Riñón/irrigación sanguínea , Masculino , Ratones , Ratones Endogámicos C57BL , Oligopéptidos/administración & dosificación , Oligopéptidos/química , Oligopéptidos/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , Daño por Reperfusión/genética , Daño por Reperfusión/patología , Daño por Reperfusión/fisiopatologíaRESUMEN
Angiotensin (Ang) II mediates pathophysiologial changes in the kidney. Ang-(1-7) by interacting with the G protein-coupled receptor Mas may also have important biological activities.In this study, renal deficiency for Mas diminished renal damage in models of renal insufficiency as unilateral ureteral obstruction and ischemia/reperfusion injury while the infusion of Ang-(1-7) to wild-type mice pronounced the pathological outcome by aggravating the inflammatory response. Mas deficiency inhibited NF-kappaB activation and thus the elevation of inflammation-stimulating cytokines, while Ang-(1-7) infusion had proinflammatory properties in experimental models of renal failure as well as under basal conditions. The Ang-(1-7)-mediated NF-kappaB activation was Mas dependent but did not involve Ang II receptors. Therefore, the blockade of the NF-kappaB-activating properties of the receptor Mas could be a new strategy in the therapy of failing kidney.
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Angiotensina I/farmacología , Inflamación/etiología , Enfermedades Renales/patología , Fragmentos de Péptidos/farmacología , Proteínas Proto-Oncogénicas/deficiencia , Receptores Acoplados a Proteínas G/deficiencia , Angiotensina I/administración & dosificación , Animales , Antihipertensivos/administración & dosificación , Antihipertensivos/farmacología , Citocinas , Inflamación/inducido químicamente , Enfermedades Renales/etiología , Ratones , Ratones Noqueados , FN-kappa B/antagonistas & inhibidores , Fragmentos de Péptidos/administración & dosificación , Proto-Oncogenes Mas , Daño por Reperfusión/patologíaRESUMEN
Cockayne syndrome and other segmental progerias with inborn defects in DNA repair mechanisms are thought to be due in part to hypersensitivity to endogenous oxidative DNA damage. The accelerated aging-like symptoms of this disorder include dysmyelination within the central nervous system, progressive sensineuronal hearing loss and retinal degeneration. We tested the effects of congenital nucleotide excision DNA repair deficiency on acute oxidative stress sensitivity in vivo. Surprisingly, we found mouse models of Cockayne syndrome less susceptible than wild type animals to surgically induced renal ischemia reperfusion injury, a multifactorial injury mediated in part by oxidative damage. Renal failure-related mortality was significantly reduced in Csb(-/-) mice, kidney function was improved and proliferation was significantly higher in the regenerative phase following ischemic injury. Protection from ischemic damage correlated with improved baseline glucose tolerance and insulin sensitivity and a reduced inflammatory response following injury. Protection was further associated with genetic ablation of a different Cockayne syndrome-associated gene, Csa. Our data provide the first functional in vivo evidence that congenital DNA repair deficiency can induce protection from acute stress in at least one organ. This suggests that while specific types of unrepaired endogenous DNA damage may lead to detrimental effects in certain tissues, they may at the same time elicit beneficial adaptive changes in others and thus contribute to the tissue specificity of disease symptoms.
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Reparación del ADN/genética , Isquemia/genética , Insuficiencia Renal/genética , Daño por Reperfusión/genética , Estrés Fisiológico/genética , Animales , Síndrome de Cockayne/genética , Síndrome de Cockayne/metabolismo , Síndrome de Cockayne/fisiopatología , Enzimas Reparadoras del ADN/genética , Modelos Animales de Enfermedad , Predisposición Genética a la Enfermedad/genética , Prueba de Tolerancia a la Glucosa , Inmunidad Innata/genética , Resistencia a la Insulina/genética , Isquemia/fisiopatología , Isquemia/prevención & control , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proteínas de Unión a Poli-ADP-Ribosa , Insuficiencia Renal/fisiopatología , Insuficiencia Renal/prevención & control , Daño por Reperfusión/fisiopatología , Daño por Reperfusión/prevención & controlRESUMEN
We tested whether transplant arteriosclerosis can be reduced by pre-treatment of the donor with immunosuppressive agents, using a rat allogeneic aorta transplantation model. Donor rats received no pre-treatment, or tacrolimus, methylprednisolone, rapamycin, or mycofenolate mofetil (MMF) 16 and 2h before explantation of the grafts. Eight weeks after transplantation, aorta allografts were harvested. Percent intima area/intima+media area (I/I+M), inflammatory cells and in situ MMP-2 and -9 activity were determined. In pre-transplantation biopsies, MMP-2 and -9 ratio, and mRNA levels for genes of interest were determined. In pre-transplantation biopsies we found no differences in MMP-2/9 ratio, and Bcl-2, Bax, TGF-beta, HO-1, p21, and HIF-1alpha mRNA expression between the groups. Aorta allografts, pre-treated with tacrolimus, showed significantly lower I/I+M ratio compared to untreated controls (p<0.01). Pre-treatment with methylprednisolone, rapamycin or MMF did not significantly reduce I/I+M ratio. In situ MMP-2/MMP-9 activity was significantly reduced in grafts treated with tacrolimus and rapamycin compared to controls (p<0.05). Immunohistochemistry revealed a high number of CD4+ cells and high CD4/CD8 ratio in grafts pre-treated with tacrolimus. Donor pre-treatment with tacrolimus significantly reduces transplant arteriosclerosis and is associated with reduced in situ MMP-2/MMP-9 activity and increased number of CD4+ cells.
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Aorta/trasplante , Enfermedad de la Arteria Coronaria/prevención & control , Inmunosupresores/administración & dosificación , Tacrolimus/administración & dosificación , Donantes de Tejidos , Animales , Aorta/anatomía & histología , Aorta/metabolismo , Recuento de Linfocito CD4 , Enfermedad de la Arteria Coronaria/enzimología , Enfermedad de la Arteria Coronaria/inmunología , Enfermedad de la Arteria Coronaria/patología , Rechazo de Injerto/prevención & control , Supervivencia de Injerto/efectos de los fármacos , Inflamación/tratamiento farmacológico , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Ratas , Ratas Endogámicas BN , Ratas Wistar , Factores de Tiempo , Túnica Íntima/efectos de los fármacosRESUMEN
The utility of nursing theory as a framework to understand, explain, and propose nursing research is essential to knowledge development. The purpose of this column is to provide an examination of the Roy adaptation model as a basis for knowledge development in bulimia nervosa. This chronic and debilitating disorder is complex, poorly understood, and characterized by repeated binge eating and purging episodes. A careful examination of the major concepts and theoretical linkages of the Roy adaptation model in relationship to bulimia nervosa is necessary to determine the value of this framework to generate future knowledge and research for practice.
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Adaptación Psicológica , Bulimia Nerviosa/psicología , Conocimiento , Modelos Psicológicos , HumanosRESUMEN
Peri-operative tissue injury triggers the development of Transplant Coronary Artery Disease (TCAD). Animal studies have shown that induction of heme oxygenase (HO)-1 protects the donor organ from the development of TCAD. To investigate the role of HO-1 in TCAD after clinical heart transplantation, we measured intragraft mRNA expression of HO-1, HIF-1alpha, TGF-beta, FLIP, and the Bcl-2/Bax balance. Immunohistochemical staining of HO-1 was performed to determine its origin. Myocardial biopsies taken at the end of the transplantation procedure (time 0), at 1 week and at 10 months after transplantation were studied from recipients with or without angiographic signs of accelerated TCAD, diagnosed after 1 year. At time 0, no differences in mRNA expression for any of the measured parameters were found between TCAD positive and negative patients. At 1 week, mRNA expression of HO-1 and TGF-beta was higher in grafts that developed accelerated TCAD (p=0.001 and p=0.0002). These higher mRNA levels were accompanied by a pro-apoptotic shift in Bcl-2/Bax (p=0.02), suggesting proneness for apoptosis via the mitochondrial pathway. Immunohistochemical staining showed that HO-1 was mainly produced by infiltrating macrophages. At 10 months, again HO-1 and TGF-beta levels were high in TCAD positive patients (p=0.02 and p=0.05), but the expression of apoptotic markers was comparable at this time point. Our results suggest that a higher HO-1 by macrophages in our patient population might be an adaptive response to tissue injury and inflammation, reflecting damage due to the transplantation procedure that finally results in TCAD.