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1.
J Mol Neurosci ; 48(3): 482-92, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22528455

RESUMEN

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a widespread neuropeptide with a diverse array of biological functions. Not surprisingly, the lack of endogenous PACAP therefore results in a variety of abnormalities. One of the important effects of PACAP is its neuroprotective and general cytoprotective role. PACAP protects neurons and other tissues against ischemic, toxic, and traumatic lesions. Data obtained from PACAP-deficient mice provide evidence that endogenous PACAP also has protective functions. Mice lacking PACAP are more vulnerable to different in vitro and in vivo insults. The present review summarizes data on the increased sensitivity of PACAP-deficient mice against harmful stimuli. Mice lacking PACAP respond with a higher degree of injury in cerebral ischemia, autoimmune encephalomyelitis, and axonal lesion. Retinal ischemic and excitotoxic injuries also produce increased cell loss in PACAP-deficient mice. In peripheral organs, kidney cell cultures from PACAP-deficient mice are more sensitive to oxidative stress and in vitro hypoxia. In vivo, PACAP-deficient mice have a negative histological outcome and altered cytokine response in kidney and small intestine ischemia/reperfusion injury. Large intestinal inflammation, toxic lesion of the pancreas, and doxorubicin-induced cardiomyopathy are also more severe with a lack of endogenous PACAP. Finally, an increased inflammatory response has been described in subacute endotoxin-induced airway inflammation and in an oxazolone-induced allergic contact dermatitis model. In summary, lack of endogenous PACAP leads to higher vulnerability in a number of injuries in the nervous system and peripheral organs, supporting the hypothesis that PACAP is part of the endogenous cytoprotective machinery.


Asunto(s)
Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/fisiología , Estrés Fisiológico/fisiología , Animales , Enfermedades Autoinmunes/fisiopatología , Cardiomiopatías/fisiopatología , Dermatitis Alérgica por Contacto/fisiopatología , Susceptibilidad a Enfermedades , Homeostasis/fisiología , Inflamación/fisiopatología , Isquemia/fisiopatología , Enfermedades Renales/fisiopatología , Enfermedades Pulmonares/fisiopatología , Ratones , Ratones Noqueados , Enfermedades del Sistema Nervioso/fisiopatología , Neurotoxinas/toxicidad , Noxas/efectos adversos , Enfermedades Pancreáticas/fisiopatología , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/deficiencia , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/genética , Heridas y Lesiones/fisiopatología
2.
Transplant Proc ; 43(10): 3694-6, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22172828

RESUMEN

The prediction of graft rejection can play an important part in graft survival. Analysis of immune reactions has shown that graft rejection shares mechanisms with recurrent abortions during pregnancy. Progesterone-induced blocking factor (PIBF), a mediator of progesterone that blocks natural killer cell activity in peripheral blood, produces antiabortive effects. The aim of this study was to examine the PIBF concentration in the urine of transplanted recipients. The study included 116 white adults (70 men and 46 women) of median age 49.3 years, who had undergone kidney transplantations. The median duration after transplantation was 3.46 years. The average period between renal disease and our measurement was 12.3 years, and the median interval between graft rejection and our study was 1.75 years. Urine samples were used to measure PIBF concentrations by an enzyme-linked immunsorbent assay. PIBF urinary concentrations decreased significantly in patients who experienced ≥1 rejection episode (31.8±2.2 ng/mL) compared with those without any episode (22.7±1.2 ng/ml; P<.01). Moreover, the urinary PIBF level was significantly lower among patients who had increased creatinine and urea nitrogen levels in blood samples (P<.05 and P<.01, respectively). Decreased PIBF values in kidney transplant patients followed previous rejection episodes. A close negative correlation was observed between urinary PIBF concentrations and blood levels of creatinine and urea nitrogen. These findings suggested that PIBF detection may predict graft rejection in transplant recipients.


Asunto(s)
Rechazo de Injerto/etiología , Trasplante de Riñón/efectos adversos , Proteínas Gestacionales/orina , Factores Supresores Inmunológicos/orina , Biomarcadores/sangre , Biomarcadores/orina , Nitrógeno de la Urea Sanguínea , Creatinina/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Rechazo de Injerto/orina , Humanos , Hungría , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Curva ROC , Factores de Tiempo , Resultado del Tratamiento
3.
Transplant Proc ; 42(6): 2287-9, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20692464

RESUMEN

Ischemia/reperfusion (I/R) injury is a serious condition that results from some surgical procedures, including intestinal transplantation. Ischemic postconditioning is defined as brief periods of reperfusion alternating with reocclusion applied during the early minutes after reperfusion. The objective of this study was to investigate the effect of ischemic postconditioning before small bowel autotransplantation. Total orthotopic intestinal autotransplantation was performed in 30 white domestic pigs. Grafts were stored in cold University of Wisconsin solution for 1, 3, or 6 hours. Duration of reperfusion was 3 hours in all grafts. Before reperfusion, the intestine was postconditioned via 3 cycles of ischemia for 30 seconds and reperfusion for 30 seconds (ischemic postconditioning protocol). Tissue from the small intestine was obtained after laparotomy (control group) and at the end of reperfusion periods. To monitor oxidative stress, tissue concentrations of malondialdehyde and reduced glutathione, and activity of superoxide dismutase were determined at spectrophotometry. Tissue damage on sections stained with hematoxylin- eosin was evaluated using a quantitative method (Scion Image software; Scion Corp, Frederick, Maryland). Our results demonstrated that ischemic postconditioning significantly decreased the reperfusion-ended lipid peroxidation value (mean +/- SEM, 142.0 +/- 7.1 micromol/g vs 125.0 +/- 2.1 micromol/g; P < .05). Moreover, the capacity and activity of endogenous antioxidant protective systems (glutathione 789+/-8.0 micromol/g vs 934 +/- 5.7 micromol/g, and superoxide dismutase 110 +/- 9 IU/g vs 126 +/- 4 IU/g; P < .05) remained higher in the ischemic postconditioning groups compared with tissues without ischemic postconditioning. At quantitative analysis, tissue injury was increased by the duration of cold preservation. The greatest injury was observed in the mucosal and submucosal layers and in the depth of crypts after 6 hours of preservation. Ischemic postconditioning significantly decreased intestinal wall injury in each group (P < .05). It was concluded that ischemic postconditioning before reperfusion mitigated oxidative stress and histologic damage during small bowel autotransplantation.


Asunto(s)
Intestino Delgado/trasplante , Poscondicionamiento Isquémico/métodos , Animales , Frío , Glutatión/metabolismo , Mucosa Intestinal/metabolismo , Intestino Delgado/irrigación sanguínea , Intestino Delgado/metabolismo , Peroxidación de Lípido , Malondialdehído/metabolismo , Músculo Liso/metabolismo , Preservación de Órganos/métodos , Superóxido Dismutasa/metabolismo , Porcinos , Trasplante Autólogo
4.
Transplant Proc ; 42(6): 2290-2, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20692465

RESUMEN

Tissue injury caused by cold preservation remains a problem in small intestinal transplantation. Pituitary adenylate cyclase-activating polypeptide (PACAP) has a central role in intestinal physiology. The objective of the present study was to compare the effects of cold ischemia injury in PACAP-38 knockout and wild-type mice after cold storage of small bowel. Cold ischemia was produced using small bowel preservation in University of Wisconsin solution at 4 degrees C in 20 PACAP-38 wild-type mice for 1, 3, and 6 hours (groups 1, 2, and 3, respectively) and 20 PACAP-38 knockout mice for 1, 3, and 6 hours (groups 4, 5, and 6, respectively). Biopsy samples of small bowel were obtained after laparotomy (control) and at the end of preservation periods. To determine oxidative stress, malondialdehyde, reduced glutathione, and superoxide dismutase concentrations were measured. Tissue damage was assessed using a quantitative method on sections stained with hematoxylin-eosin. After 6 hours, tissue lipid peroxidation was increased significantly in PACAP-38 knockout mice (mean +/- SD, 153.04 +/- 7.2 micromol/g) compared with sham-operated mice (110.44 +/- 5.5 micromol/g) and wild-type mice (120.0 +/- 1.1 micromol/g) (P < .05). The capacity and activity of the endogenous antioxidant system decreased significantly after 3 and 6 hours of preservation (reduced glutathione, 808.7 +/- 5.2 micromol/g and 720.4 +/- 8.7 micromol/g; and superoxide dismutase, 125.1 +/- 1.4 IU/g and 103.3 +/- 1.9 IU/g vs 212.11 +/- 5.8 IU/g; P < .05). Quantitative histologic analysis demonstrated destruction of mucosal and submucosal layers and crypts in knockout mice compared with wild-type mice. These processes depended on duration of cold preservation. These findings demonstrate that PACAP-38 has a key role in protection against intestinal cold preservation injury.


Asunto(s)
Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/deficiencia , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/metabolismo , Adenosina , Alopurinol , Animales , Antioxidantes/metabolismo , Criopreservación/métodos , Glutatión/metabolismo , Insulina , Intestino Delgado/metabolismo , Peroxidación de Lípido , Malondialdehído/metabolismo , Ratones , Ratones Noqueados , Preservación de Órganos/métodos , Soluciones Preservantes de Órganos , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/genética , Rafinosa , Superóxido Dismutasa/metabolismo
5.
Transplant Proc ; 42(6): 2333-5, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20692474

RESUMEN

There is increasing evidence that nonmelanoma skin cancers (NMSCs) are the most frequently observed tumors in transplant recipients. The incidence of posttransplantation NMSC was determined using our dermatologic screening program. Included in the study were 116 white adults (70 men and 46 women; median age, 49.3 years) who had undergone kidney or combined kidney-pancreas transplantation, with follow-up from September 2008 to December 2009. All patients underwent a full skin examination for NMSC, and completed a standardized questionnaire. Screening resulted in detection of 16 NMSCs in 11 patients out of 116 (9.5%). Lesions were equally distributed by sex, and were detected at a median of 4.1 years posttransplantation. Histologic analysis verified 13 basal cell carcinomas and 3 squamous cell carcinomas (ratio, 4:1). The incidence of NMSC was significantly greater in patients who received cyclosporine immunosuppression therapy (16 vs 1; P < .05), had experienced 2 or more painful sunburns before transplantation (10 vs 11), or worked outdoors (10 vs 11). These data indicate the relevance of skin cancer surveillance in transplant recipients. Our results correspond to international statistics except for the ratio of basal cell carcinoma to squamous cell carcinoma. Further studies are needed to elucidate the reasons for this difference.


Asunto(s)
Trasplante de Órganos/efectos adversos , Neoplasias Cutáneas/epidemiología , Carcinoma Basocelular/epidemiología , Carcinoma de Células Escamosas/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Hungría/epidemiología , Trasplante de Riñón/efectos adversos , Masculino , Persona de Mediana Edad , Trasplante de Páncreas/efectos adversos , Piel/patología , Neoplasias Cutáneas/clasificación , Encuestas y Cuestionarios , Factores de Tiempo
6.
Transplant Proc ; 42(6): 2336-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20692475

RESUMEN

Transplant recipients are at high risk of nonmelanoma skin cancer (NMSC). Ultraviolet radiation can generate oxygen free radicals (OFRs), leading to oxidative stress and carcinogenesis, primarily during immunosuppression therapy. In the present study, changes in oxidative stress were examined in transplant recipients with and without NMSC. The study included 116 white adults who had undergone kidney or combined kidney-pancreas transplantation. Dermatologic follow-up revealed 16 NMSCs (13.8%). To monitor oxidative stress, peripheral blood samples were used to measure malondialdehyde (MDA), reduced glutathione, sulfhydryl (-SH) groups, OFRs, and activity of myeloperoxidase, superoxide dismutase, and catalase. The mean (SD) plasma MDA concentration was significantly greater in patients without NMSC compared with healthy control individuals (0.48+/-0.05 nmol/mL; P < .05), whereas MDA concentration in hemolysate was slightly increased. In peripheral blood samples, the MDA concentration in both plasma (0.71+/-0.03 nmol/mL) and hemolysate (87.74+/-1.25 nmol/mL) was significantly increased in the NMSC group compared with the healthy control group (0.24+/-0.05 nmol/mL vs 75.87+/-2.8 nmol/mL; P < .05) or patients without NMSC (0.48+/-0.04 nmol/mL vs 79.62+/-2.77 nmol/mL; P < .05). The reduced glutathione concentration was significantly decreased in the -SH groups compared with the healthy control group (P < .05). Antioxidant activity of myeloperoxidase (0.78+/-0.05 IU/mL) and catalase (1855.8+/-45.41 IU/mL) was significantly increased in the group without NMSC compared with the healthy control group (0.41+/-0.1 IU/mL vs 1642.07+/-82.96 IU/mL) and the NMSC group (0.93+/-0.03 IU/mL vs 2180.5+/-15.03 IU/mL). The superoxide dismutase activity was decreased slightly but not significantly. Total production of OFRs was significantly greater in the NMSC group compared with the non-NMSC group or the healthy control group (P < .05). These findings suggest that an imbalance exists between pro-oxidant and antioxidant status in transplant recipients, with a significant difference in patients with vs without NMSC.


Asunto(s)
Trasplante de Riñón/efectos adversos , Trasplante de Órganos/efectos adversos , Estrés Oxidativo , Trasplante de Páncreas/efectos adversos , Neoplasias Cutáneas/epidemiología , Catalasa/sangre , Femenino , Radicales Libres/sangre , Glutatión/sangre , Humanos , Masculino , Malondialdehído/sangre , Persona de Mediana Edad , Neoplasias Cutáneas/sangre , Neoplasias Cutáneas/fisiopatología , Compuestos de Sulfhidrilo/sangre , Superóxido Dismutasa/sangre
7.
Ann N Y Acad Sci ; 1163: 512-6, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19456402

RESUMEN

The neuropeptide pituitary adenylate cyclase activating polypeptide (PACAP) and its receptors are widely expressed in the nervous system and various other tissues. PACAP exerts strong anti-apoptotic effects in neuronal cell lines and, according to recent data, also in non-neuronal cells. The peptide is present in the cardiovascular system and has various distinct effects. We have demonstrated earlier that PACAP has protective effects against in vitro ischemia/reperfusion-induced apoptosis in cardiomyocytes. Preconditioning with brief intermittent periods of ischemia is known to provide protection against ischemic injury. The aim of the present study was to investigate whether PACAP could enhance the protective effect of preconditioning against in vitro ischemic injury. Cultured cardiomyocytes were exposed to brief preconditioning ischemia followed by 2 h ischemia and 4 h reperfusion. Both PACAP treatment and preconditioning alone significantly increased cell viability and decreased the ratio of cell death. Pretreatment with PACAP was found to further reduce the level of cleaved caspase-8 but it did not lead to additional survival rate when compared to cells treated with PACAP or preconditioning alone. These results show that although both PACAP and preconditioning have a protective effect against ischemia/reperfusion-induced cardiomyocyte apoptosis, their effects are not additive.


Asunto(s)
Apoptosis/efectos de los fármacos , Miocitos Cardíacos/citología , Miocitos Cardíacos/efectos de los fármacos , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/farmacología , Daño por Reperfusión/patología , Animales , Células Cultivadas , Precondicionamiento Isquémico Miocárdico , Ratas , Ratas Wistar
8.
Transplant Proc ; 41(1): 60-2, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19249476

RESUMEN

Cold preservation prior to small bowel transplantation can moderate tissue oxidative injury. This stress triggers several intracellular pathways via mitogen activated protein (MAP) kinases. MAP kinases include the extracellular signal related kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 MAP kinase. Pituitary adenylate cyclase-activating polypeptide (PACAP) plays a central role in intestinal physiology. We sought to investigate the effect of PACAP on the activation of MAP kinases during cold preservation of the small bowel. Total orthotopic intestinal autotransplantation was performed on 40 Wistar rats. Perfused grafts were stored in University of Wisconsin (UW) solution for 1 (GI), 2 (GII), 3 (GIII), or 6 hours (GIV) without or with 30 PACAP, namely 1 (GV), 2 (GVI), 3 (GVII), or 6 hours (GVIII). After 3 hours of reperfusion in all groups, the activation of MAP kinases were measured using immunocytochemistry of small bowel tissue. Among the UW preserved grafts (GI-GIV), phosphorylated ERK1/2 level were decreased, while phosphorylated JNK1/2 and p38 MAP kinase activation were elevated compared with control levels. In GV-GVIII PACAP we observed enhanced phospho-ERK1/2 appearance with decreased JNK and p38 MAP kinase activity at the end of the reperfusion periods. We concluded that cold preservation decreased phosphorylated ERK1/2 levels and increased JNK1/2 and p38 MAP kinase activities, which meant that cold storage triggered apoptotic cell death. In contrast, PACAP treatment induced signalling pathways protective against oxidative injury by MAP kinases in bowel tissue.


Asunto(s)
Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Intestino Delgado/enzimología , Intestino Delgado/trasplante , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Preservación de Órganos/métodos , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/farmacología , Adenosina , Alopurinol , Animales , Activación Enzimática/efectos de los fármacos , Quinasas MAP Reguladas por Señal Extracelular/efectos de los fármacos , Glutatión , Supervivencia de Injerto , Insulina , Proteínas Quinasas JNK Activadas por Mitógenos/efectos de los fármacos , Masculino , Soluciones Preservantes de Órganos , Rafinosa , Ratas , Ratas Wistar , Trasplante Autólogo
9.
Transplant Proc ; 41(1): 57-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19249475

RESUMEN

Tissue injury caused by cold preservation and reperfusion during small bowel transplantation remains an unsolved problem. Increasing evidence suggests that pituitary adenylate cyclase-activating polypeptide (PACAP) has protective effects in several ischemia-reperfusion (I/R) models. This study investigated the effect of PACAP-38 on oxidative stress in autotransplanted intestine. We established sham-operated, I/R, and autotransplanted groups in Wistar rats (n = 55). We applied ischemia for 1 (GI), 2 (GII), or 3 hours (GIII). In autotransplanted groups, we performed total orthotopic intestinal autotransplantation. Grafts were preserved in University of Wisconsin (UW) solution for 1 (GIV), 2 (GV), 3 (GVI), or 6 (GVII) hours and in PACAP-38-containing UW for 1 (GVIII), 2 (GIX), 3 (GX), or 6 (GXI) hours. Reperfusion lasted 3 hours in each group. Endogenous PACAP-38 values were measured by radioimmunoassay. Oxidative stress parameters malondialdehyde (MDA), reduced glutathione (GSH), and superoxide dismutase (SOD) were measured in tissue homogenates. Concentration of endogenous PACAP-38 significantly decreased in GI to GIII compared with the sham-operated animals following I/R periods (P < .05). Cold preservation in UW and reperfusion of the intestine increased the level of tissue MDA in GIV to GVII, which correlated with the duration of cold storage. The content of GSH decreased in GIV to GVII to levels that were significantly different between GIV and GVIII and between GVII and GXI. SOD activity decreased dramatically in GIV to GVII with significantly higher activity in GIX to GXI. Our findings confirmed that I/R decreased endogenous PACAP-38 concentration. Administration of PACAP-38 to UW solution mitigated the oxidative injury during intestinal autotransplantation.


Asunto(s)
Intestinos/irrigación sanguínea , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/metabolismo , Daño por Reperfusión/fisiopatología , Adenosina , Alopurinol , Animales , Frío , Glutatión/metabolismo , Insulina , Masculino , Malondialdehído/metabolismo , Preservación de Órganos/métodos , Soluciones Preservantes de Órganos , Rafinosa , Ratas , Ratas Wistar , Superóxido Dismutasa/metabolismo
10.
Oftalmologia ; 53(4): 79-82, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20361656

RESUMEN

UNLABELLED: The purpose of this study was to evaluate the incidence of corneal pathology that presents indication for cornea/transplant, treatment and follow-up of these patients. MATERIALS AND METHODS: A retrospective analysis has been undertaken at the Tg. Mures Ophthalmology Hospital. In the study we have included all patients who had corneal pathology with intact deeper ocular structures. We have examined the treatment of these cases and their admittance to corneal transplantation. RESULTS: In 2008 in 99 cases of the 3246 hospitalized patients such a corneal condition has been described that presented indication for corneal transplantation. Most common causes were corneal leucomas, corneal ulcers, bullous keratopathy and corneal dystrophies and degenerations. Fourteen patients tried to benefit from corneal transplant abroad financed by the National Health Insurance Office; others went on their own expense. All together four patients appeared for postoperative control at our Hospital. CONCLUSIONS: We have found 99 cases of corneal transplant indication at our Hospital's patients and only a fraction of them have undergone surgery. We can point out a very low level of admittance and a great need for a regional corneal transplantation centers.


Asunto(s)
Enfermedades de la Córnea/cirugía , Trasplante de Córnea , Enfermedades de la Córnea/epidemiología , Femenino , Supervivencia de Injerto , Hospitales Especializados , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Oftalmología , Estudios Retrospectivos , Rumanía/epidemiología , Resultado del Tratamiento , Agudeza Visual
11.
Eur Surg Res ; 41(2): 226-30, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18520151

RESUMEN

AIMS: We evaluated the possibility that repeated ischemic preconditioning or N-acetylcysteine (NAC) could prevent ischemia-reperfusion injury as determined by indocyanine green plasma disappearance rate (ICG-PDR) or has favorable hemodynamic effects during reperfusion in an in vivo canine liver model. METHODS: Under general anesthesia, 3 groups of mongrel dogs (n = 5 per group) were subjected to (1) 60-min hepatic ischemia, (2) same ischemia preceded by intravenous administration of 150 mg kg(-1) NAC, and (3) three episodes of IPC (10-min ischemia followed by 10-min reperfusion) prior to same ischemia. Hepatic reperfusion was maintained for a further 180 min, with hemodynamic and hepatic function parameters monitored throughout. RESULTS: Plasma disappearance rate of indocyanine green and serum levels of aspartate transferase and alanine transferase showed no significant differences between groups. Although liver injury was obvious, reflected by hemodynamic, blood gas, and liver function tests, NAC and IPC failed to prevent decay in hepatic function in this canine model. CONCLUSION: The results do not support the hypothesis that short-term use of NAC and IPC is beneficial in hepatic surgery.


Asunto(s)
Acetilcisteína/farmacología , Precondicionamiento Isquémico/métodos , Hepatopatías/metabolismo , Hepatopatías/prevención & control , Daño por Reperfusión/metabolismo , Daño por Reperfusión/prevención & control , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Colorantes/farmacocinética , Modelos Animales de Enfermedad , Perros , Verde de Indocianina/farmacocinética
12.
Gen Comp Endocrinol ; 153(1-3): 115-23, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17270184

RESUMEN

Pituitary adenylate cyclase activating polypeptide (PACAP) is a widely distributed neuropeptide that has various different functions in the nervous system and in non-neural tissues. Little is known about the effects of PACAP in endothelial cells. The aim of the present study was to investigate the effects of PACAP on endothelial cell survival and apoptotic signaling pathways under oxidative stress. Mouse hemangioendothelioma (EOMA) cells were exposed to 0.5mM H(2)O(2) which resulted in a marked reduction of cell viability and a parallel increase of apoptotic cells assessed by MTT test and flow cytometry. Co-incubation with 20nM PACAP1-38 increased cell viability and reduced the percentage of apoptotic cells. Flow cytometry analysis showed that oxidative stress reduced the phosphorylation of the anti-apoptotic ERK and increased the phosphorylation of the pro-apoptotic JNK and p38 MAP kinases. PACAP1-38 treatment ameliorated these changes: levels of phospho-ERK were elevated and those of phospho-JNK and p38 were decreased. All these effects were abolished by simultaneous treatment with the PACAP antagonist PACAP6-38. In summary, our results show that PACAP effectively protects endothelial cells against the apoptosis-inducing effects of oxidative stress.


Asunto(s)
Apoptosis/efectos de los fármacos , Células Endoteliales/efectos de los fármacos , Estrés Oxidativo , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/farmacología , Sustancias Protectoras/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Estrés Oxidativo/efectos de los fármacos , Células Tumorales Cultivadas
13.
Transplant Proc ; 38(6): 1800-2, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16908285

RESUMEN

Ischemic preconditioning (IPC), which is obtained by exposure to brief periods of vascular occlusion, improves organ tolerance to prolonged ischemia. The aim of this study was to evaluate the threshold level of NF-kB activation in small intestine during an IPC procedure. Various intestinal IPC were performed on 20 Wistar rats in seven groups: group I (GI, nonpreconditioned); group II (GII, 1-minute ischemia and 1-minute reperfusion); group III (GIII, two cycles of 1-minute ischemia and 1-minute reperfusion); group IV (GIV, 2-minutes ischemia and 2-minutes reperfusion); group V (GV, two cycles of 2-minute ischemia and 2-minute reperfusion); group VI (GVI, 5-minute ischemia and 10-minute reperfusion); group VII (GVII, two cycles of 5-minute ischemia and 10-minute reperfusion). Bowel biopsies were collected after laparotomy (control) as well as at 30, 60, and 120 minutes following IPC. We determined the cytoplasmic and nuclear NF-kB by a chemiluminescence-based ELISA method. Our results showed low, constant NF-kB levels in GI. In the preconditioned groups (GII-GVII), NF-kB was significantly elevated at 30 minutes following IPC (P < .05 vs control). After 1 hour, NF-kB activity decreased to the control level. However, 2 hours after IPC both forms of NF-kB were elevated significantly again, which was independent of the number of IPC cycles (P < .05 vs control). Our experiments revealed that one cycle of 1-minute ischemia and 1-minute reperfusion is a critical threshold level for NF-kB activation during small bowel IPC. Longer and more IPC cycles did not result in further elevation of NF-kB activation.


Asunto(s)
Intestino Delgado/irrigación sanguínea , Precondicionamiento Isquémico/métodos , FN-kappa B/metabolismo , Animales , Isquemia/fisiopatología , Masculino , Modelos Animales , Ratas , Ratas Wistar
14.
Peptides ; 27(1): 87-94, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16095757

RESUMEN

Pituitary adenylate cyclase activating polypeptide (PACAP) has well-known neuroprotective effects, and one of the main factors leading to neuroprotection seems to be its anti-apoptotic effects. The peptide and its receptors are present also in the heart, but whether PACAP can be protective in cardiomyocytes, is not known. Therefore, the aim of the present study was to investigate the effects of PACAP on oxidative stress-induced apoptosis in cardiomyocytes. Our results show that PACAP increased cell viability by attenuating H2O2-induced apoptosis in a cardiac myocyte culture. PACAP also decreased caspase-3 activity and increased the expression of the anti-apoptotic markers Bcl-2 and phospho-Bad. These effects of PACAP were counteracted by the PACAP antagonist PACAP6-38. In summary, our results show that PACAP is able to attenuate oxidative stress-induced cardiomyocyte apoptosis.


Asunto(s)
Apoptosis/fisiología , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Estrés Oxidativo/fisiología , Polipéptido Hipofisario Activador de la Adenilato-Ciclasa/fisiología , Animales , Supervivencia Celular/fisiología , Células Cultivadas , Activación Enzimática/fisiología , Peróxido de Hidrógeno/metabolismo , Miocitos Cardíacos/enzimología , Fragmentos de Péptidos/fisiología , Proteínas Proto-Oncogénicas c-bcl-2/fisiología , Ratas , Ratas Wistar , Proteína Letal Asociada a bcl/fisiología
15.
Transplant Proc ; 36(2): 286-8, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15050135

RESUMEN

Ischemic preconditioning (IPC) has been defined as short periods of ischemia with intermittent reperfusion. IPC induces two phases of protection. We sought to investigate the effects of classic and delayed preconditioning on oxidative stress markers prior to autotransplantation. Total orthotopic intestinal autotransplantation was performed on 18 mongrel dogs in three groups: group I (GI, nonpreconditioned), group II (GII, classic preconditioned), and group III (GIII, delayed preconditioned). In GI 3-hour cold preservation in University of Wisconsin solution was followed by 1 hour of reperfusion. In GII before this procedure the intestine was preconditioned by occlusion of the mesenteric artery with four cycles each of 5 minutes of ischemia and 10 minutes of reperfusion (IPC protocol). In GIII on day 1 the animals underwent the IPC protocol, and autotransplantation was performed on day 2. Oxidative stress parameters included malondialdehyde (MDA), reduced glutathione (GSH), and superoxide dismutase (SOD) measurements in tissue samples. Our results showed increased lipid peroxidation with decreased GSH level and SOD activity in GI (control: 254.38 +/- 18.32 IU/g; reperfused: 55.01 +/- 26.40 IU/g; P <.05). In GII MDA was slightly elevated, and the GSH concentration was increased markedly. Furthermore, better preservation of SOD activity was observed at the end of the reperfusion. Meanwhile, in GIII GSH was significantly increased, indicating the activation of the endogenous antioxidant protective system (control: 382.13 +/- 24.22 micromol/L per gram; reperfused: 515.25 +/- 26.36 micromol/L per gram; P <.05). Moreover, SOD surpassed the control activity. Our findings confirmed that both forms of preconditioning mitigate the severity of oxidative stress prior to preservation and autotransplantation. Delayed preconditioning is more effective to protect bowel tissue against oxidative injury.


Asunto(s)
Intestino Delgado/trasplante , Precondicionamiento Isquémico/métodos , Estrés Oxidativo/fisiología , Trasplante Autólogo/métodos , Animales , Perros , Intestino Delgado/irrigación sanguínea , Masculino , Preservación de Órganos/métodos
16.
Magy Seb ; 54(5): 320-4, 2001 Oct.
Artículo en Húngaro | MEDLINE | ID: mdl-11723737

RESUMEN

Extensive lesions of the cervical trachea can occur as a result of malformation, inflammation, tumor disease or trauma. If a short segment of the trachea is resected primary anastomosis may be possible. The problem of how to treat lesions longer than 50% of total tracheal length is still unresolved. The aim of our study was to clarify the possible use and limitations of small bowel interposition for tracheal replacement in veterinary model. We resected 6 cm of the cervical trachea of 5 adult mongrel dogs. Autolog jejunum free flap was used for replacement. The wall of the implant was supported with 5 polytetrafluoroethylene rings placed on the outer surface of the bowel perpendicular to its axis. We performed the surgery in two stages. Intraoperative tracheostomy was necessary in every case. The tracheal tube extended through the whole length of the implant. The survivals, the viability of the graft and complications were examined. The length of survival ranged between 18 h and 72 h. In one case obstruction of the tracheal tube occurred, in 3 cases the micro vessel anastomosis of the graft thrombosed, in one case both complications developed. In our experience use of the small bowel flap was complicated with fatal technical difficulties. The micro vessel anastomosis proved to be highly risky. Further investigations are needed to improve the results with this method.


Asunto(s)
Yeyuno/trasplante , Colgajos Quirúrgicos , Tráquea/cirugía , Animales , Perros , Yeyuno/patología , Necrosis , Tráquea/patología , Trasplante Autólogo
17.
Magy Seb ; 54(1): 60-4, 2001 Feb.
Artículo en Húngaro | MEDLINE | ID: mdl-11299869

RESUMEN

The difficulty at transplanting the small bowel mainly is caused by the biology of the intestine. It is highly immunogenic, is one of the most sensitive tissues to ischemia-reperfusion injury. Our aims were to investigate changes of oxygen free radical mediated reactions after autotransplantation at different preservation times and perfusion fluids. Our results prove that this model is feasible to examine ischemia-reperfusion injury in the small intestine. Euro Collins (EC) is a suitable preserving solution for small bowel transplantation. There was no significant lipid peroxidation within the first 6 hours of graft preservation. However superoxide dismutase (SOD) activity was dramatically reduced during reperfusion in the tissues samples. Significant increase of reduced glutathione at the same time can be explained by compensatory mechanism to neutralize increased free radical production.


Asunto(s)
Intestino Delgado/metabolismo , Intestino Delgado/trasplante , Estrés Oxidativo , Daño por Reperfusión/metabolismo , Animales , Perros , Radicales Libres/metabolismo , Glutatión/metabolismo , Técnicas In Vitro , Intestino Delgado/irrigación sanguínea , Intestino Delgado/enzimología , Flujometría por Láser-Doppler , Masculino , Malondialdehído/metabolismo , Microcirculación , Daño por Reperfusión/etiología , Circulación Esplácnica , Superóxido Dismutasa/metabolismo , Trasplante Autólogo
18.
Orv Hetil ; 141(44): 2375-9, 2000 Oct 29.
Artículo en Húngaro | MEDLINE | ID: mdl-11105553

RESUMEN

UNLABELLED: The aim of the study was to analyse the effects of GH replacement therapy (1 year duration) on body composition, carbohydrate metabolism, thyroid hormone metabolism and bone mineral density in 8 adults with growth hormone deficiency (5 women, 3 men; mean age 40 years). Mean maintenance dose of GH was 1.5 IU/day-1.76 IU/day for women and 1.07 IU/day for men, respectively--determined according to individual patient requirements. Serum insulin-like growth factor-I standard deviation score increased from -5.4 to 0.0 (p < 0.001). There was a significant negative relationship between serum insulin-like growth factor-I standard deviation score at the start of therapy and the increase in this score (r = -0.85; p < 0.05). The waist:hip ratio decreased after 12 months by 0.039 (p < 0.05). The glycosylated hemoglobin increased (4.43 +/- 0.56% vs. 5.86 +/- 0.27; p < 0.05), and a negative correlation of the baseline glycosylated hemoglobin to the glycosylated hemoglobin increase was found (r = -0.88; p < 0.01). Both the free triiodothyronine and free triiodothyronine:free thyroxine ratio increased (3.09 +/- 0.22 vs. 4.17 +/- 0.40; p < 0.05, and 0.234 +/- 0.02 vs. 0.324 +/- 0.04; p < 0.01), and a positive relationship was observed between this ratio at the start of therapy and the increase in the ratio (r = 0.76, p < 0.05). The bone mineral density of lumbar spine and femoral neck expressed as z-score increased (-1.18 +/- 0.56 vs. -0.75 +/- 0.48; p < 0.01 and -0.06 +/- 0.60 vs. 0.43 +/- 0.43; p < 0.05), while the bone mineral density of forearm was unchanged. CONCLUSIONS: Growth hormone replacement leads to a decrease in visceral fat, modulates the thyroid hormone levels by increasing peripheral conversion of thyroxine to triiodothyronine and probably is a physiological regulator of peripheral thyroxine metabolism, slightly deteriorates the carbohydrate metabolism, and results in an increase of bone mineral density of lumbar spine and femoral neck.


Asunto(s)
Terapia de Reemplazo de Hormonas , Hormona de Crecimiento Humana/deficiencia , Hormona de Crecimiento Humana/uso terapéutico , Tejido Adiposo , Adulto , Composición Corporal , Constitución Corporal , Densidad Ósea , Carbohidratos de la Dieta/metabolismo , Femenino , Hemoglobina Glucada/metabolismo , Hormonas/sangre , Hormona de Crecimiento Humana/administración & dosificación , Humanos , Factor I del Crecimiento Similar a la Insulina/metabolismo , Masculino , Persona de Mediana Edad , Hormonas Tiroideas/sangre , Resultado del Tratamiento , Vísceras
19.
Acta Vet Hung ; 48(3): 285-91, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11402712

RESUMEN

Serum/plasma fructosamine (SeFa) concentration is a reliable indicator used in human diabetic control. Tests for monitoring the carbohydrate/energy metabolism of (farm) animals are less commonly performed in veterinary laboratories, since most of the reliable determinations, both automated and manual, are relatively expensive. The aim of this study was to develop a precise, money- (and time-) saving automated micro method for measuring SeFa. ELISA microplates (20 microL samples and 200 microL reagents) and an automatic microplate autoreader were used. The classical nitroblue tetrazolium (NBT) stain reagent solution of Johnson et al. (1982) was modified using a SIGMA reagent to render it stable for up to one year. SeFa concentrations measured by the new method in 30 human blood plasma samples were compared with values obtained by the standard (generally used) LaRoche kit procedure. Fifteen cow, 13 dog and 18 chicken plasma samples were assayed by the new automated 'micro' method as well as by the manual test tube 'macro' method commonly used earlier. The modified reagent was applied for both methods. The coefficient of correlation (r) between the results obtained by the two methods was consistently between 0.94 and 0.98 (p < 0.001).


Asunto(s)
Costos y Análisis de Costo , Ensayo de Inmunoadsorción Enzimática/métodos , Fructosamina/sangre , Animales , Bovinos , Pollos , Perros , Humanos , Indicadores y Reactivos , Especificidad de la Especie
20.
Orv Hetil ; 140(42): 2345-7, 1999 Oct 17.
Artículo en Húngaro | MEDLINE | ID: mdl-10560262

RESUMEN

Studied the diagnostic value of measurements of insulin-like growth factor binding protein-3 compared to insulin-like growth factor-1 as a parameter of disease activity in patients with active (n = 12, 8 females, 4 males, 29-69 years old) and inactive (n = 14, 11 females, 3 males, 28-58 years old) acromegaly. Patients were assigned to the active group if they had GH levels > or = 2 ng/ml, to the inactive group if they had growth hormone levels < 2 ng/ml after 75 g glucose challenge. The absolute serum insulin-like growth factor-1 concentration (526 +/- 66 ng/ml vs. 272 +/- 61 ng/ml, p = 0.015; mean +/- SE) and the insulin-like growth factor-1 standard deviation score (3.23 +/- 0.33 vs. 0.67 +/- 0.58, p = 0.0013) was higher in the active than in the inactive group, but no significant difference was seen between the corresponding insulin-like growth factor binding protein-3 values (7270 +/- 1500 vs. 5340 +/- 1050 ng/ml). Positive significant correlation was found between insulin-like growth factor-1 and insulin-like growth factor binding protein-3 both in the active (n = 12, r = 0.55, p < 0.05) and in the inactive (n = 14, r = 0.61, p < 0.05) group. A significant negative correlation existed between insulin-like growth factor binding protein-3 and age in the inactive (r = 0.58, n = 14; p < 0.05), but not in the active (r = 0.35, n = 12) group. The diagnostic value of insulin-like growth factor binding protein-3 is less than that of the insulin-like growth factor-1. Conclude that the insulin-like growth factor binding protein-3 has smaller suitability to determine the activity of acromegaly than the insulin like-growth factor-1 measurement.


Asunto(s)
Acromegalia/diagnóstico , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Acromegalia/metabolismo , Acromegalia/fisiopatología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad
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