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1.
Neuroscience ; 374: 13-24, 2018 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-29391132

RESUMEN

Some of the neurobehavioral deficits identified in children with Fetal Alcohol Spectrum Disorders (FASDs) have been recapitulated in a binge model of gestational third trimester-equivalent ethanol (EtOH) exposure, in which Sprague-Dawley rats are intragastrically intubated between post-natal day (PD) 4 and PD9 with high doses of EtOH. In this model, the ameliorating effects of choline (Chol) administration on hippocampus-dependent behaviors altered by EtOH have also been extensively documented. In the present study, we investigated the effects of EtOH (5 g/kg/day) and/or Chol (100 mg/kg/day) on morphometric parameters of CA1 pyramidal neurons by Golgi-Cox staining followed by Neurolucida tracing and analysis. We found that EtOH increased apical dendrite complexity in male and female pups neonatally exposed to EtOH. EtOH did not significantly affect basal dendrite parameters in female and male rats. Interestingly, Chol treatments decreased basal dendrites' length, number, and maximal terminal distance in male pups. When pups were co-treated with EtOH and Chol, Chol did not rescue the effect of EtOH. In conclusion, EtOH increases while Chol decreases dendritic length and arborization of hippocampal CA1 neurons in PD9 rats. We hypothesize that developmental EtOH exposure induces a premature maturation of neurons, leading to early restriction of neuronal plasticity while Chol treatments delay the normal program of neuronal maturation and therefore prolong the window of maximal plasticity. Chol does not prevent the effects of developmental alcohol exposure on hippocampal pyramidal neurons' morphology characterized in the present study, although whether prolonged Chol administration after developmental EtOH exposure rectifies EtOH damage remains to be assessed.


Asunto(s)
Región CA1 Hipocampal/crecimiento & desarrollo , Región CA1 Hipocampal/patología , Colina/toxicidad , Etanol/toxicidad , Trastornos del Espectro Alcohólico Fetal/patología , Células Piramidales/patología , Animales , Animales Recién Nacidos , Región CA1 Hipocampal/efectos de los fármacos , Tamaño de la Célula/efectos de los fármacos , Dendritas/efectos de los fármacos , Dendritas/patología , Modelos Animales de Enfermedad , Femenino , Masculino , Células Piramidales/efectos de los fármacos , Distribución Aleatoria , Ratas Sprague-Dawley
2.
Transplant Proc ; 42(4): 1251-2, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20534273

RESUMEN

The preliminary experience of the first Italian program of pediatric intestinal transplantation is presented herein. A multidisciplinary group with broad experience in pediatric solid organ transplantation started the program. Nine children with complications of chronic intestinal failure were listed for transplantation. One child died on the waiting list; one received an isolated liver transplantation; three isolated intestinal; three multivisceral; and one, a combined liver/intestine transplantation. There was no in-hospital mortality, and all children were weaned from parenteral nutrition. The recipient of the multivisceral graft died after 14 months for unknown causes. All other recipients are alive after a median follow-up of 13 months. Patient and graft actuarial survivals for recipients of intestinal grafts were 100% at 1 year and 75% at 2 years.


Asunto(s)
Intestinos/trasplante , Niño , Preescolar , Infecciones por Citomegalovirus/cirugía , Supervivencia de Injerto , Humanos , Lactante , Atresia Intestinal/cirugía , Seudoobstrucción Intestinal/cirugía , Vólvulo Intestinal/cirugía , Italia , Trasplante de Hígado , Síndrome del Intestino Corto/cirugía , Tasa de Supervivencia , Sobrevivientes , Vísceras/trasplante
3.
Transplant Proc ; 42(4): 1262-4, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20534276

RESUMEN

INTRODUCTION: Use of extended criteria donors is one of the strategies to face the scarcity of donors for lung transplantation. METHODS: Between November 2002 and May 2009, we performed 52 LTs in 50 recipients, 10 of whom (group A) received lungs from donors aged 55 years or older (median, 58.5; range, 56-66 years) for comparison with 28 patients (group B) transplanted with lungs from donors younger than 55 years (median, 25.5; range, 15-54 years). We excluded 9 children and 3 recipients of combined liver plus lung transplantations from the study. RESULTS: Recipient age, gender, and indications for transplantation did not differ significantly between the 2 groups. Neither were there significant differences in PaO2/FiO2 ratios before lung retrieval, or length of the ischemic time The first PaO2/FiO2 on arrival to the intensive care unit (ICU) and the median length of ICU stay were similar. All patients, except 2 who died in the operating theatre, were extubated between 3 and 216 hours after the transplantation. Hospital mortality was similar in both groups: 3 patients in group A and 2 in group B (P = .1). The median portions of the predicted 1-second forced expiratory volume (FEV1) at 6 months after transplantation did not differ in the 2 groups: 62.4% in group A versus 70% in group B (P = .85). CONCLUSION: Lung grafts from donors older than 55 years can be effectively used for transplantation, thus increasing the total organ pool.


Asunto(s)
Trasplante de Pulmón/fisiología , Selección de Paciente , Donantes de Tejidos/estadística & datos numéricos , Adolescente , Adulto , Factores de Edad , Anciano , Puente Cardiopulmonar , Causas de Muerte , Femenino , Volumen Espiratorio Forzado , Humanos , Trasplante de Hígado/fisiología , Trasplante de Pulmón/mortalidad , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/mortalidad , Resultado del Tratamiento , Adulto Joven
4.
Am J Transplant ; 7(10): 2433-8, 2007 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17845577

RESUMEN

Sequential bilateral single lung-liver transplantation (SBSL-LTx) is a therapeutic option for patients with end stage lung and liver disease (ESLLD) due to cystic fibrosis (CF). A few cases have been reported, all of them were performed with the use of cardio-pulmonary by-pass (CPB). We performed SBSL-LTx in three young men affected by CF. All the recipients had respiratory failure and portal hypertension with hypersplenism. Along with lung transplants, two patients received a whole liver graft and one an extended right graft from an in situ split liver. During transplantation neither CPB nor veno-venous by-pass (VVB) were employed. Immunosuppression was based on basiliximab, tacrolimus, steroids and azathioprine. The three recipients are alive with a median follow-up of 670 days (range 244-1,533). Combined SBSL-LTx is a complex but effective procedure for the treatment of ESLLD due to CF, not necessarily requiring the use of CPB or VVB.


Asunto(s)
Puente Cardiopulmonar , Fibrosis Quística/complicaciones , Fibrosis Quística/cirugía , Fallo Hepático/cirugía , Trasplante de Hígado/métodos , Enfermedades Pulmonares/cirugía , Trasplante de Pulmón/métodos , Adulto , Humanos , Periodo Intraoperatorio , Fallo Hepático/etiología , Enfermedades Pulmonares/etiología , Masculino , Resultado del Tratamiento
5.
Hum Exp Toxicol ; 26(4): 355-60, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17615117

RESUMEN

Cholesterol is an essential component of cell membranes and plays an important role in signal transduction. This brief overview presents evidence from the literature that ethanol may affect cholesterol homeostasis and that, in the developing brain, this may be involved in its developmental neurotoxicity. The effects caused by inborn errors of cholesterol synthesis and by in utero ethanol exposure present several similarities in humans (eg, Smith-Lemli-Opitz syndrome and fetal alcohol syndrome), as well as in animal models. Ethanol has a cholesterol-reducing effect on the cardiovascular system, and a protective effect against Alzheimer's disease, whose pathogenesis has been linked to altered cholesterol homeostasis in the brain. In vitro, ethanol affects several functions that are mediated by cholesterol and important for brain development, such as glial cell proliferation, synaptogenesis, neuronal survival and neurite outgrowth. The brain contains high levels of cholesterol, mostly synthesized in situ. Astrocytes produce large amounts of cholesterol that can be released by these cells and utilized by neurons to form synapses. Ethanol up-regulates the cholesterol transporter ATP binding cassette A1 and cholesterol efflux from primary astrocyte cultures without affecting cholesterol synthesis.


Asunto(s)
Química Encefálica/efectos de los fármacos , Encéfalo/crecimiento & desarrollo , Encéfalo/fisiología , Depresores del Sistema Nervioso Central/farmacología , Colesterol/metabolismo , Etanol/farmacología , Homeostasis/efectos de los fármacos , Animales , Colesterol/fisiología , Humanos
6.
Transplant Proc ; 37(2): 1141-2, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15848649

RESUMEN

Early portal vein thrombosis (PVT) represents a serious complication after liver transplantation (OLTx). From October 1997 through July 2004, 260 OLTx were performed in 231 children, including 189 of left lateral segments (LLS). We retrospectively analyzed the incidence and the outcome of early PVT in this group. A daily doppler US scan was performed during the first week after transplantation. Early PVT occurred in 14 patients (8%), 10 males and four females of median age 0.77 years. The main indication for primary transplantation was biliary atresia (10), followed by Byler's disease (2), acute liver failure on cryptogenetic cirrhosis (1), and Alagille syndrome (1). Four children underwent retransplantation; three cases of thrombectomy and revision of the anastomosis, two children were treated with beta blockers, one of whom had a later failed attempt at percutaneous revascularization and eventually a meso-caval shunt. Five patients were followed with observation and no treatment. Among the four patients who died, three were in the retransplantation group and one in the thrombectomy and revision of the anastomosis group; the overall mortality was 28%. With a median follow up of 399 days, 10 patients are alive with an actuarial survival at 1 and 5 years of 72%, and graft survival rates at 1 and 5 years of 64%. PVT represents a serious complication after pediatric OLTx with LLS grafts. Prompt detection and aggressive surgical treatment in selected cases are required to reduce the mortality and graft loss.


Asunto(s)
Hepatectomía/métodos , Trasplante de Hígado , Vena Porta , Complicaciones Posoperatorias/epidemiología , Trombosis/epidemiología , Cadáver , Niño , Supervivencia de Injerto , Humanos , Hepatopatías/clasificación , Hepatopatías/cirugía , Trasplante de Hígado/mortalidad , Trasplante de Hígado/fisiología , Reoperación/estadística & datos numéricos , Estudios Retrospectivos , Análisis de Supervivencia , Donantes de Tejidos , Recolección de Tejidos y Órganos/métodos
7.
Transplant Proc ; 37(2): 1143-5, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15848650

RESUMEN

Liver transplantation (OLT) remains a major medical and surgical challenge in small patients. From October 1997 through July 2004, 17 babies less than 6 kg underwent 18 OLTs. Median age and weight were 3 months (range = 1 to 9) and 4.7 kg (range = 2.2 to 5.8). Two whole, one reduced, and 15 split-liver grafts (left lateral segments) were obtained from donors of median age and weight of 11.6 years (range = 0.5 to 62) and 50 kg (range = 7 to 63). Donor-to-recipient median weight ratio (D/R) was 9.1 kg (range = 1.3 to 17.6) and median graft-to-recipient weight ratio (GRWR) was 5% (range = 3.1 to 10). The incidence of biliary complications was 23%. The only vascular complication was a portal vein thrombosis (6%). Fourteen patients (79%) are alive with good graft function at a median follow-up of 39 months (range = 0.5 to 74). Three patients (all status 1) died on postoperative day 285 (brain death), 17 (multiorgan failure), and 229 (cardiovascular failure during retransplantation). Actuarial patient survivals at 6 months and 6 years are 94% and 78% while graft survivals are 89% and 74%, respectively. Currently all the patients listed as UNOS status 2 and 3 (73%) at the time of transplant are alive. During the same period one premature neonate (1.8 kg) who presented with fulminant hepatic failure died on the waiting list after 12 days. Our data confirm that the extensive use of a split-liver technique from small adult or pediatric cadaveric donors can offer the benefits of liver transplantation to small pediatric candidates with excellent results.


Asunto(s)
Trasplante de Hígado , Adolescente , Adulto , Peso Corporal , Niño , Enfermedades de la Vesícula Biliar/epidemiología , Humanos , Lactante , Recién Nacido , Italia , Trasplante de Hígado/mortalidad , Persona de Mediana Edad , Vena Porta , Complicaciones Posoperatorias/clasificación , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Análisis de Supervivencia , Trombosis , Donantes de Tejidos/estadística & datos numéricos , Resultado del Tratamiento , Enfermedades Vasculares/epidemiología
8.
Transplant Proc ; 37(2): 1146-8, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15848651

RESUMEN

We reviewed the clinical data of 30 children-hospitalized for acute liver failure in the last 6 years. Ten patients were not listed for liver transplantation OLTX. Their clinical conditions gradually improved and they are all alive without deficit. Among 20 patients listed, 15 underwent urgent OLTX. Two children died on the waiting list and three were suspended from waiting list after few days because of improvement. Survival according to age class was analyzed dividing the patients into two groups: A, age 1 year or less versus B, age between 1 and 16 years. The patient survival was 86% at 6 months and 61% both at 1 and 2 years. Survival at 6 months and 1 and 2 years was 88%, 67%, and 45% for the patients in group A and 83%, 83%, and 83% for the patients in group B (P = NS). Observing graft-to-recipient weight ratio and donor-to-recipient weight ratio most patients received an optimal sized graft. The split-liver technique is considered the preferred method of liver transplantation even in the pediatric patients with acute liver failure; especially in the setting of a cooperative system in which all livers that are suitable for split-liver transplantation are shared between centers. In order to have the best chance for survival, children with acute liver failure should be referred as soon as possible to an highly specialized pediatric liver transplantation center that can offer all the treatment modalities that are currently available.


Asunto(s)
Fallo Hepático Agudo/cirugía , Adolescente , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Italia , Hepatopatías/mortalidad , Hepatopatías/cirugía , Estudios Retrospectivos , Resultado del Tratamiento , Listas de Espera
9.
Transplant Proc ; 37(2): 1149-50, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15848652

RESUMEN

In this study we analyzed the features of 12 patients who underwent liver transplantation for progressive familial intrahepatic cholestasis (Byler's disease [BD]) in view of the technical features of the OLTx, incidence and type of complications, need for retransplantation, as well as patient and graft survivals. BD was the indication in 12 patients of median age 1.32 years and median weight 10 kg. Median follow-up was 670 days. Major surgical complications requiring reintervention occurred in three patients. No thrombosis of the hepatic artery was observed. Infections with positive blood cultures were diagnosed in four patients. One patient had a biliary anastomotic stenosis successfully treated by percutaneous techniques. Four patients had episodes of acute rejection treated with steroids. Two patients were retransplanted, both of whom died in the early postoperative period due to hepatic vein thrombosis and venoenteric fistula. The actuarial patient and graft survival was 83% at 1 year and 83% at 5 years. Split-liver grafts represent an excellent organ supply for these patients, achieving good results with no mortality on the waiting list.


Asunto(s)
Cirrosis Hepática Biliar/cirugía , Trasplante de Hígado , Adolescente , Niño , Preescolar , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
10.
Transplant Proc ; 37(2): 1153-4, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15848654

RESUMEN

Biliary atresia (BA) represents the most frequent indication for liver transplantation (OLTX) in the pediatric population. The aim of this paper was to present a series collected over the last 7 years from October 1997 through July 2004, including 260 pediatric OLTX in 231 patients. BA was the indication in 137 patients. There were 69 boys and 68 girls of mean weight 10.68 kg and median age 0.9 years. As a primary transplant, 99 patients received a LLS graft; 27 a whole graft; four a I+IV-VIII segment, and two a I-IV segment. Mean follow up was 1047 days (range, 1-2496 day). Infections were diagnosed in 45 patients, vascular complications in 27 patients. Surgical complications that required reintervention occurred in 25 patients. In 41 cases biliary complications occurred, 11 requiring reintervention. 16 patients were retransplanted. In two cases another re-OLTx was performed. Currently 126 patients are alive, showing an actuarial 1 year survival of 92% and 5 year 91%, with actuarial graft survivals of 85% at 1 year and 82% at 3 and 5 years. Our results confirm the effectiveness of OLTx for the treatment of children with BA and a failed Kasai procedure. Split liver grafts represent an excellent organ supply for these patients, achieving optimal results with no mortality on the waiting list.


Asunto(s)
Atresia Biliar/cirugía , Trasplante de Hígado , Sistema del Grupo Sanguíneo ABO , Adolescente , Incompatibilidad de Grupos Sanguíneos , Niño , Preescolar , Femenino , Supervivencia de Injerto , Humanos , Lactante , Complicaciones Intraoperatorias/epidemiología , Trasplante de Hígado/inmunología , Trasplante de Hígado/métodos , Trasplante de Hígado/mortalidad , Masculino , Complicaciones Posoperatorias/epidemiología , Reoperación/estadística & datos numéricos , Estudios Retrospectivos , Análisis de Supervivencia
11.
Transplant Proc ; 37(2): 1164-6, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15848657

RESUMEN

INTRODUCTION: We report our experience of in situ split-liver transplantation (SLT) for adult patients and compare the results with those achieved with whole-liver transplantation (WLT). METHOD: From November 1997 to December 2003, 109 liver transplantation were performed in 104 adult patients including 90 WLT (83%) and 19 SLT (17%) grafts. Fifteen extended right grafts (ERG, segments I + IV to VIII) were obtained with in situ split-liver procedures, generating also left lateral segment grafts, which were transplanted at our institution or elsewhere. Four left lobe (LL, segments I to IV) and right lobe (segments V to VIII) grafts were obtained by a modified in situ procedure for adult recipients. UNOS status, percentage of primary or secondary transplantation, and underlying liver disease were similar among patients receiving whole versus split grafts. Donors were older in whole than ERG cohorts (53 vs 26 years, P < .001). Procurement parameters and intraoperative profiles of transplant procedure were comparable among the groups. RESULTS: Median follow-up was 18 months (range: 1 to 73). Four patients with whole (4%) and no patient with ERG underwent retransplantation (P = NS). One- and 3-year patient survivals were 86% and 79% with WLT versus 93% and 93% with ERG (P = NS). One- and 3-year graft survivals were 84% and 75% with WLT versus 93%, and 93% with ERG (P = NS). Incidence of vascular complications was 8% with WLT, 13% with ERG (P = NS). The incidence of biliary complications was 13% in WLT, 27% in ERG (P = NS). CONCLUSIONS: The use of ERG from in situ split livers for adult transplantation allowed us to obtain results comparable or even better than those obtained with WLT. Split-liver transplantation is an effective, safe mechanism to expand the cadaveric donor pool.


Asunto(s)
Hepatectomía/métodos , Trasplante de Hígado , Recolección de Tejidos y Órganos/métodos , Adulto , Anciano , Niño , Preescolar , Femenino , Asignación de Recursos para la Atención de Salud , Hemodinámica , Humanos , Hepatopatías/clasificación , Hepatopatías/cirugía , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Tamaño de los Órganos , Reoperación/estadística & datos numéricos , Estudios Retrospectivos , Resultado del Tratamiento
12.
Transplant Proc ; 37(2): 1174-6, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15848660

RESUMEN

Alagille syndrome (AS) is a dominantly inherited, multisystem disorder involving the liver, heart, eyes, face, and skeleton. From October 1997 through July 2004, 260 pediatric orthotopic liver transplantations (OLTx) were performed in 231 patients. This report describes 21 patients of median age 1.95 years (range, 0.7-16.7) who had alagille syndrome. We present the technical features of the OLTx, incidence and type of complications, medical conditions related to the syndrome, need for retransplantation, as well as patient and graft survival rates. A split liver technique was used in 16 patients (76%) who received a left lateral segment (LLS) graft whereas 7 patients (33%) received a whole liver. Only cadaveric donors were used. The major surgical complications requiring reintervention in 11 patients (52%) included biliary problems (19%) and vascular complications (17%). One case of hepatic artery thrombosis required retransplantation. Three recipients (14%) died. All other patients are alive with an actuarial survival rate of 90% at 1 year and 80% at 5 years. The actuarial graft survival rate is 85% at 1 year and 75% at 5 years. Patients with AS, despite the associated cardiovascular anomalies, can be treated successfully by a combined approach between cardiologist, radiologist, cardiothoracic, and liver transplant surgeons. With careful planning and operative management, the results are comparable with those obtained with other more common cholestatic diseases.


Asunto(s)
Síndrome de Alagille/cirugía , Trasplante de Hígado/estadística & datos numéricos , Análisis Actuarial , Cateterismo Cardíaco , Niño , Estudios de Seguimiento , Humanos , Trasplante de Hígado/mortalidad , Complicaciones Posoperatorias/clasificación , Complicaciones Posoperatorias/epidemiología , Estudios Retrospectivos , Análisis de Supervivencia , Factores de Tiempo
13.
Environ Toxicol Pharmacol ; 19(3): 395-400, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-21783503

RESUMEN

In certain cases, the consumption of food or beverages can lead to intoxication and disease. Such food-induced intoxications may be due to microbial toxins, to toxic substances naturally occurring in some foods, or to contaminants or residues of various kinds. Some of these agents have neurotoxic properties and may contribute to the etiology of certain psychiatric disorders or neurodegenerative diseases. This paper reviews a selected number of dietary neurotoxicants that naturally, or as a result of human interventions, find their way into food or beverages, and have been associated with neurotoxic outcomes in humans. Chosen examples include domoic acid, a phycotoxin associated with amnesic shellfish poisoning; ß-N-oxalylamine-l-alanine (l-BOAA), present in chickling peas and believed to be responsible for neurolathyrism; and two alcohols, methanol and ethanol, which can cause severe neurotoxic effects in adults and the developing fetus.

14.
Toxicol Lett ; 149(1-3): 67-73, 2004 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-15093250

RESUMEN

Central nervous system dysfunctions (most notably microencephaly and mental retardation) are among the most significant effects of in utero exposure to ethanol. Ethanol causes alterations of both neuronal and glial cells. In particular, ethanol has been shown to inhibit proliferation of astroglial cells stimulated by certain, but not all mitogens. Here, we review evidence that acetylcholine, by activating the M(3) subtype of muscarinic receptors, increases DNA synthesis in rat and human astroglial cells and that this effect is inhibited by low ethanol concentrations (10-100mM). Of the several signal transduction pathways activated by these receptors in astrocytes or astrocytoma cells, ethanol appears to target activation of phospholipase D, leading to a decrease in phosphatidic acid, a decreased activation of the atypical protein kinase C zeta and decreased down-stream activation of p70S6 kinase and of nuclear factor-kappaB. Inhibition of this pathway by ethanol occurs at the same concentrations which effectively inhibit proliferation. Inhibition of astroglial cell proliferation by ethanol may contribute to the microencephaly present in most children diagnosed with the fetal alcohol syndrome.


Asunto(s)
Depresores del Sistema Nervioso Central/toxicidad , Etanol/toxicidad , Neuroglía/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Animales , Astrocitos/efectos de los fármacos , División Celular/efectos de los fármacos , Humanos , Mitógenos/farmacología , Enfermedades del Sistema Nervioso/inducido químicamente , Ratas , Receptores Muscarínicos/efectos de los fármacos
15.
Neuroscience ; 120(4): 941-50, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12927200

RESUMEN

Activation of muscarinic receptors leads to proliferation of astroglial cells and this effect is inhibited by ethanol. Among the intracellular pathways involved in the mitogenic action of muscarinic agonists, activation of the atypical protein kinase C zeta (PKC zeta) appears to be of most importance, and is also affected by low ethanol concentrations. PKC zeta has been reported to activate nuclear factor kappaB (NF-kappaB), a transcription factor that has been shown to play an important role in cell proliferation. The aim of this study was, therefore, to determine whether muscarinic receptors would activate NF-kappaB in astroglial cells, whether such activation would play a role in the mitogenic action of muscarinic agonists, and whether it would represent a possible target for ethanol. Carbachol activated NF-kappaB in human 1321N1 astrocytoma cells, as evidenced by translocation of the p65 subunit of NF-kappaB to the nucleus, phosphorylation and degradation of IkappaBalpha in the cytosol, and increase NF-kappaB binding to DNA. Carbachol also induced translocation of p65 to the nucleus in primary rat astrocytes. Carbachol-induced NF-kappaB activation was mediated by the M3 subtype of muscarinic receptors and appeared to involve Ca(2+) mobilization and activation of PKC epsilon and PKC zeta, but not PI3-kinase and mitogen-activated protein kinase. The NF-kappaB peptide inhibitor SN50, but not the inactive peptide SN50M, strongly inhibited carbachol-induced astrocytoma cells proliferation and p65 translocation to the nucleus. Increased DNA synthesis was also antagonized by the IkappaBalpha kinase inhibitor BAY 11-7082. Ethanol (25-100 mM) inhibited the translocation of p65 and the binding of NF-kappaB to DNA in both 1321N1 astrocytoma cells and primary rat cortical astrocytes. Together, these results suggest that activation of NF-kappaB by muscarinic receptors in astroglial cells is important for carbachol-induced DNA synthesis and that ethanol-mediated inhibition of cell proliferation may be due in part to inhibition of NF-kappaB activation.


Asunto(s)
Astrocitos/efectos de los fármacos , Depresores del Sistema Nervioso Central/farmacología , Ácido Egtácico/análogos & derivados , Etanol/farmacología , FN-kappa B/metabolismo , Receptores Muscarínicos/metabolismo , Astrocitos/metabolismo , Astrocitoma , Atropina/farmacología , Western Blotting/métodos , Carbacol/farmacología , Línea Celular , Estructuras Celulares/efectos de los fármacos , Estructuras Celulares/metabolismo , Quelantes/farmacología , Agonistas Colinérgicos/farmacología , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Ácido Egtácico/farmacología , Ensayo de Cambio de Movilidad Electroforética/métodos , Inhibidores Enzimáticos/farmacología , Trietyoduro de Galamina/farmacología , Humanos , Antagonistas Muscarínicos/farmacología , FN-kappa B/antagonistas & inhibidores , Antagonistas Nicotínicos/farmacología , Toxina del Pertussis/farmacología , Piperidinas/farmacología , Timidina/metabolismo , Factores de Tiempo , Tritio/metabolismo
17.
Toxicol Lett ; 127(1-3): 197-205, 2002 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-12052659

RESUMEN

Developmental neurotoxicity can be ascribed to in utero exposure to exogenous substances or to exposure of the fetus to endogenous compounds that accumulate because of genetic mutations. One of the best recognized human neuroteratogens is ethanol. The Fetal Alcohol Syndrome (FAS) is characterized by growth deficiency, particular facial features, and central nervous system (CNS) dysfunctions (mental retardation, microencephaly and brain malformations). Abuse of toluene by pregnant women can lead to an embryopathy (fetal solvent syndrome, (FSS)) whose characteristics are similar to FAS. Phenylketonuria (PKU) is a genetic defect in phenylalanine (Phe) metabolism. Offspring of phenylketonuric mothers not under strict dietary control are born with maternal PKU (mPKU), a syndrome with similar characteristics as FAS and FSS. While ethanol has been shown to cause neuronal death, no such evidence is available for toluene or Phe and/or its metabolites. On the other hand, alterations in astrocyte proliferation and maturation have been found, mostly in in vitro studies, which may represent a potential common mode of action for at least some of the CNS effects found in FAS, mPKU, and FSS. Further in vivo and in vitro studies should validate this hypothesis and elucidate possible molecular targets.


Asunto(s)
Exposición Materna/efectos adversos , Enfermedades del Sistema Nervioso/embriología , Xenobióticos/efectos adversos , Trastornos del Sistema Nervioso Inducidos por Alcohol/embriología , Trastornos del Sistema Nervioso Inducidos por Alcohol/etiología , Animales , Etanol/efectos adversos , Etanol/toxicidad , Femenino , Trastornos del Espectro Alcohólico Fetal/etiología , Trastornos del Espectro Alcohólico Fetal/patología , Humanos , Enfermedades del Sistema Nervioso/etiología , Enfermedades del Sistema Nervioso/genética , Síndromes de Neurotoxicidad , Fenotipo , Fenilcetonuria Materna/complicaciones , Embarazo , Tolueno/efectos adversos , Tolueno/toxicidad , Xenobióticos/toxicidad
19.
Growth Factors ; 18(4): 227-36, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11519822

RESUMEN

Acetylcholine muscarinic receptors are a family of five G-protein-coupled receptors widely distributed in the central nervous system and in peripheral organs. Activation of certain subtypes of muscarinic receptors (M1, M3, M5) has been found to modulate DNA synthesis in a number of cell types. In several cell types acetylcholine, by activating endogenous or transfected muscarinic receptors, can indeed elicit cell proliferation. In other cell types, however, or under different experimental conditions, activation of muscarinic receptors has no effect, or inhibits DNA synthesis. A large number of intracellular pathways are being investigated to define the mechanisms involved in these effects of muscarinic receptors; these include among others, phospholipase D, protein kinases C and mitogen-activated-protein kinases. The ability of acetylcholine to modulate DNA synthesis through muscarinic receptors may be relevant in the context of brain development and neoplastic growth.


Asunto(s)
ADN/biosíntesis , Receptores Muscarínicos/metabolismo , Acetilcolina/metabolismo , Acetilcolina/farmacología , Animales , División Celular/efectos de los fármacos , División Celular/fisiología , Humanos , Líquido Intracelular/metabolismo , Agonistas Muscarínicos/farmacología , Receptores Muscarínicos/clasificación , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
20.
J Neurochem ; 78(3): 590-9, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11483662

RESUMEN

As lead has been shown to activate protein kinase C (PKC), and gliomas are reported to be highly dependent on PKC for their proliferation, this study was undertaken to investigate whether lead may act as a mitogen in human astrocytoma cells, and to determine the role of PKC in this effect. Lead acetate (from 100 nM to 100 microM) induced a concentration- and time-dependent increase in DNA synthesis, as measured by incorporation of [methyl-3H]thymidine into cell DNA, without causing any cytotoxicity. Flow cytometric analysis showed that lead was able to stimulate the cell cycle transition from the G0/G1 phase to the S/G2 phase, resulting in increased percentage of cells in the latter phase. Western blot analyses showed that lead induced translocation of PKCalpha, but not of PKCepsilon or PKCzeta, from the cytosolic to the particulate fraction, with a concomitant increase in PKC enzyme activity. Prolonged exposure to lead caused down-regulation of PKCalpha, but not of PKCepsilon. The effect of lead on DNA synthesis was mediated through PKC as evidenced by the finding that two PKC inhibitors, GF 109203X and staurosporine, as well as down-regulation of PKC through prolonged treatment with 12-O-tetradecanoylphorbol 13-acetate, blocked lead-induced DNA synthesis. Further experiments using a pseudosubstrate peptide targeting classical PKCs and selective down-regulation of specific PKC isoforms indicated that the effect of lead on DNA synthesis was mediated by PKCalpha. Altogether, these results suggest that lead stimulates DNA synthesis in human astrocytoma cells by a mechanism that involves activation of PKCalpha.


Asunto(s)
Astrocitos/efectos de los fármacos , División Celular/efectos de los fármacos , ADN/biosíntesis , Isoenzimas/metabolismo , Compuestos Organometálicos/farmacología , Proteína Quinasa C/metabolismo , Astrocitos/citología , Astrocitos/metabolismo , Astrocitoma , Carbacol/farmacología , Carcinógenos/farmacología , Ciclo Celular/efectos de los fármacos , Agonistas Colinérgicos/farmacología , Medio de Cultivo Libre de Suero , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/farmacología , Citometría de Flujo , Humanos , Immunoblotting , Indoles/farmacología , Isoenzimas/antagonistas & inhibidores , Maleimidas/farmacología , Proteína Quinasa C/antagonistas & inhibidores , Proteína Quinasa C-alfa , Estaurosporina/farmacología , Acetato de Tetradecanoilforbol/farmacología , Células Tumorales Cultivadas
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