Role of CB2 cannabinoid receptor in the development of food addiction in male mice.

The endocannabinoid system plays an important role in multiple behavioral responses due to its wide distribution in the central nervous system. The cannabinoid CB1 receptor was associated to the loss of behavioral control over food intake occurring during food addiction. The cannabinoid CB2 receptor (CB2R) is expressed in brain areas canonically associated with addictive-like behavior and was linked to drug-addictive properties. In this study, we evaluated for the first time the specific role of the CB2R in food addiction by using a well-validated operant mouse model of long-term training to obtain highly palatable food. We have compared in this model the behavioral responses of wild-type mice, mutant mice constitutively lacking CB2R, and transgenic mice overexpressing CB2R. The lack of CB2R constitutes a protective factor for the development of food addiction and the impulsive and depressive-like behavior associated. In contrast, the overexpression of CB2R induces a vulnerable phenotype toward food addiction after long-term exposure to highly palatable chocolate pellets. Relevant transcriptomic changes were associated to resilience and vulnerability to food addiction depending on the genotype, which provides a mechanistic explanation for these behavioral changes. Therefore, CB2R may constitute a potential therapeutic target for the loss of eating control and the comorbid emotional effects associated to food addiction.

Long-term Follow-up of a Randomized Trial of Tacrolimus or Cyclosporine A Microemulsion in Children Post Liver Transplantation.

The aim of this study was to determine the long-term efficacy and safety of tacrolimus (Tac) and cyclosporine immunosuppression in pediatric liver transplantation (LTx). METHODS: One hundred fifty-six patients who had taken part in a multicenter, randomized, open, parallel study of Tac and corticosteroids versus cyclosporine A microemulsion (CyA-ME), corticosteroids, and azathioprine. Patients were assessed at regular intervals up to 14 y after LTx. Analysis was conducted descriptively. RESULTS: In a long-term follow-up, there was a similar incidence of acute rejection (Tac versus CyA-ME, 5 versus 8) and graft loss (5 versus 10). There were 11 deaths in the cohort, which were from infectious complications/malignancy in the Tac group (n = 2/5) and from chronic rejection/liver failure in the CyA-ME group (n = 3/6). A similar incidence of Epstein-Barr virus and posttransplant lymphoproliferative disease was observed (8 versus 8, 3 versus 3). However, there was a greater incidence of cosmetic adverse events in the CyA-ME cohort, with higher incidences of hypertrichosis (8 versus 27) and gum hyperplasia (20 versus 6). Growth improved equally in both groups. Overall, 81% of patients randomized to Tac remained on Tac therapy at study end, compared with 31% of patients randomized to CyA-ME. Common reasons for switching from CyA-ME included steroid-resistant/acute rejection (n = 12/8) and cosmetic changes (n = 8). CONCLUSIONS: This study is the first prospective, observational follow-up study of pediatric patients randomized to Tac and CyA-ME to evaluate long-term outcomes. Our analysis was limited by the degree of switchover between the cohorts; however, there were fewer deaths from chronic rejection/liver failure and reduced adverse events with Tac. Long-term use of Tac and Tac combination therapy appears to be safe and effective immunosuppression for pediatric LTx recipients.

[Assessment of the severity scores in patients included in a sepsis code in an Emergency Departament]. / Valoración de escalas de gravedad en pacientes incluidos en un código sepsis en un servicio de urgencias hospitalario.

OBJECTIVE: The objective of the study is to determine the usefulness of the SOFA (Sequential Organ Failure Assessment), quick SOFA (qSOFA), LODS (Logistic Organ Dysfunction System) and EWS (Early Warning Score) scores to predict in-hospital mortality among septic patients attended in the emergency department; to evaluate what factors are associated with mortality; and develop a predictive model of in-hospital mortality. METHODS: Retrospective study including patients over 14 years of age included in the sepsis code of an Emergency Department of a University Hospital between November 2013 and September 2015. Demographic variables, hemodynamic and analytical variables, and in-hospital mortality were collected to obtain qSOFA, SOFA, LODS, EWS scores. Receiver operating characteristic curves were constructed for each score. Logistic regression was used to evaluate the probability of in-hospital mortality. RESULTS: A total of 349 patients were analyzed, median age 72.7 (range 86), males: 54.4%. The in-hospital mortality was 21.8%. AUC obtained: LODS: 0.73 (IC 95% 0.67-0.80; p<0.001), EWS: 0.73 (IC 95% 0.65-0.81; p<0.001), SOFA: 0.72 (IC 95% 0.65- 0.78; p<0.001), qSOFA: 0.67 (IC 95% 0.58-0.76; p<0.001). After the multivariate analysis, these were the independent factors associated with in-hospital mortality: Oxygen saturation ≤92%, Glasgow coma score <14, lactate ≥2mmol/L (p<0.05). Two prognostic models were generated: MPRO1: age, oxygen saturation ≤92% and Glasgow coma score <14, AUC: 0.78 (IC 95% 0.72-0.84; p<0.001) and MPRO2 formed by the previous ones and lactate ≥2mmol/L, AUC: 0.82 (IC 95% 0.76-0.87; p<0.001). CONCLUSIONS: SOFA score and the new developed scores could be useful in asses the risk of in-hospital mortality in patients included in the sepsis code.

Prognostic accuracy of SIRS criteria, qSOFA score and GYM score for 30-day-mortality in older non-severely dependent infected patients attended in the emergency department.

The aim of this study was to determine the accuracy of systemic inflammatory response syndrome (SIRS), quick Sepsis-related Organ Failure Assessment (qSOFA) score and GYM score to predict 30-day mortality in older non-severely dependent patients attended for an episode of infection in the emergency department (ED). We performed an analytical, observational, prospective cohort study including patients 75 years of age or older, without severe functional dependence, attended for an infectious process in 69 Spanish EDs for 2-day three-seasonal periods. Demographic, clinical and analytical data were collected. The primary outcome was 30-day mortality after the index event. We included 1071 patients, with a mean age of 83.6 [standard deviation (SD) 5.6] years; 544 (50.8%) were men. Seventy-two patients (6.5%) died within 30 days. SIRS criteria ≥ 2 had a sensitivity of 65% [95% confidence interval (CI) 53.1-75.9] and a specificity of 49% (95% CI 46.0-52.3), a qSOFA score ≥ 2 had a sensitivity of 28% (95% CI 18.2-39.8) and a specificity of 94% (95% CI 91.9-95.1), and a GYM score ≥ 1 had a sensitivity of 81% (95% CI 69.2-88.6) and a specificity of 45% (95% CI 41.6-47.9). A GYM score ≥ 1 and a qSOFA score ≥ 2 were the cut-offs with the highest sensitivity (p < 0.001) and specificity (p < 0.001), respectively. The area under the curve (AUC) was 0.73 (95% CI 0.66-0.79; p < 0.001) for the GYM score, 0.69 (95% CI 0.61-0.76; p < 0.001) for the qSOFA score and 0.65 (95% CI 0.59-0.72; p < 0.001) for SIRS. A GYM score ≥ 1 may be the most sensitive score and a qSOFA score ≥ 2 the most specific score to predict 30-day mortality in non-severely dependent older patients attended for acute infection in EDs.

Topiramate increases the rewarding properties of cocaine in young-adult mice limiting its clinical usefulness.

RATIONALE: Topiramate is an anticonvulsant drug which has been evaluated as a therapeutic option for the treatment of cocaine addiction during the last decade. OBJECTIVES: The purpose of this study was to evaluate the effects of topiramate on the reinforcing actions of cocaine. To this aim, the topiramate-mediated regulation of acquisition and extinction phases of the cocaine conditioned place preference (CPP) was assessed in young-adult mice using three experimental designs. METHODS: Topiramate (50 mg/kg, p.o.) was given as follows: (1) during cocaine (1 and 25 mg/kg, i.p.) conditioning sessions (4 days) and cocaine (25 mg/kg) post-conditioning session; (2) 2 weeks before and during cocaine conditioning (25 mg/kg); and (3) during extinction of CPP induced by cocaine (25 mg/kg). In the first experimental design, changes in tyrosine hydroxylase (TH) and dopamine transporter (DAT) gene expressions were measured in the ventral tegmental area (VTA). RESULTS: Topiramate significantly increased cocaine-induced CPP and delayed or failed to produce extinction after the first cocaine reinstatement extinction in the first and second experiments. Furthermore, treatment with topiramate after place conditioning blocked the extinction of cocaine-induced CPP. TH and DAT gene expression in the VTA was significantly lower both with topiramate alone and in combination with cocaine compared with animals receiving only cocaine. CONCLUSIONS: These findings suggest that topiramate increases the rewarding properties of cocaine, at least in part, by regulating dopaminergic signaling in the mesolimbic circuit. Consequently, the results of this study do not support the use of topiramate for the treatment of problems related to cocaine dependence. HIGHLIGHTS: • Topiramate increases the rewarding properties of cocaine in CPP • Topiramate alters dopaminergic signaling in the mesolimbic circuit • Topiramate delays the extinction of cocaine-induced CPP • TH and DAT gene expression in the VTA decreases with topiramate and/or with cocaine • Results show that it should limit the use of topiramate in cocaine-dependent subjects.

Association between maltreatment and polydrug use among adolescents.

Different studies have related sexual and physical abuse during childhood and adolescence to the development of substance abuse disorders. Nevertheless, we are not aware of the role that other more common maltreatment types, such as neglect, will play among the most risky pattern of consumption: the polydrug use. A clinical sample of 655 adolescents, divided into two groups: polydrug users and non-polydrug users, were assessed on their pattern of drug consumption, history of childhood maltreatment, current psychopathology and their family history of alcoholism. Polydrug users had a greater prevalence of all types of maltreatment, although the most associated to this group were sexual abuse and emotional neglect. Other relevant variables to adolescent consumption were: the diagnosis of depressive disorder, the presence of anxiety traits and the family history of alcohol dependence. Polydrug users have higher risks of having had problems during infancy and adolescence, such as maltreatment and other psychopathological conditions, with the addition of family history of alcoholism. Accordingly, practitioners should take into account that those variables may influence polydrug abuse because it is the most risky pattern for subsequent dependence of substances, and they should always be considered during treatment.

Interpretación del análisis básico de orina en el deportista / Interpretation of basic urinalysis in athletes

El análisis básico de orina es un método fácil y rápido para obtener información diagnóstica sobre enfermedades que afectan fundamentalmente al sistema urinario. No obstante, la realización de ejercicio físico intenso por parte de un individuo sano puede causar cambios en varios órganos, particularmente en el tracto urinario. Hematuria, proteinuria, son anomalías que se encuentran al producirse la práctica deportiva, tanto en deportes sin contacto como en deportes con contacto. Es importante saber diferenciar cuando nos encontramos ante alteraciones benignas debido a esta práctica deportiva y diferenciarlas de estados patológicos verdaderos, excluyendo diagnósticos erróneos de enfermedad renal o del tracto urinario inferior (AU)

Basic urinalysis is a quick and easy method to obtain diagnostic information on diseases that primarily affect the urinary system. However, performing intense physical exercise by healthy individuals can cause changes in various organs, particularly in the urinary tract. Hematuria and proteinuria are abnormalities commonly found after sports activity, This phenomenon can occur in non-contact sports as well as in contact sports. It is important to differentiate between benign alterations in sports practice and true pathological conditions, excluding misdiagnosis of kidney or lower urinary tract disease (AU)

[Interpretation of basic urinalysis in athletes]. / Interpretación del análisis básico de orina en el deportista.

Basic urinalysis is a quick and easy method to obtain diagnostic information on diseases that primarily affect the urinary system. However, performing intense physical exercise by healthy individuals can cause changes in various organs, particularly in the urinary tract. Hematuria and proteinuria are abnormalities commonly found after sports activity, This phenomenon can occur in non-contact sports as well as in contact sports. It is important to differentiate between benign alterations in sports practice and true pathological conditions, excluding misdiagnosis of kidney or lower urinary tract disease.

Regulatory role of the cannabinoid CB2 receptor in stress-induced neuroinflammation in mice.

BACKGROUND AND PURPOSE: Stress exposure produces excitotoxicity and neuroinflammation, contributing to the cellular damage observed in stress-related neuropathologies. The endocannabinoids provide a homeostatic system, present in stress-responsive neural circuits. Here, we have assessed the possible regulatory role of cannabinoid CB2 receptors in stress-induced excitotoxicity and neuroinflammation. EXPERIMENTAL APPROACH: We used wild type (WT), transgenic overexpressing CB2 receptors (CB2xP) and CB2 receptor knockout (CB2-KO) mice exposed to immobilization and acoustic stress (2 h·day(-1) for 4 days). The CB2 receptor agonist JWH-133 was administered daily (2 mg·kg(-1), i.p.) to WT and CB2-KO animals. Glutamate uptake was measured in synaptosomes from frontal cortex; Western blots and RT-PCR were used to measure proinflammatory cytokines, enzymes and mediators in homogenates of frontal cortex. KEY RESULTS: Increased plasma corticosterone induced by stress was not modified by manipulating CB2 receptors. JWH-133 treatment or overexpression of CB2 receptors increased control levels of glutamate uptake, which were reduced by stress back to control levels. JWH-133 prevented the stress-induced increase in proinflammatory cytokines (TNF-α and CCL2), in NF-κB, and in NOS-2 and COX-2 and in the consequent cellular oxidative and nitrosative damage (lipid peroxidation). CB2xP mice exhibited anti-inflammatory or neuroprotective actions similar to those in JWH-133 pretreated animals. Conversely, lack of CB2 receptors (CB2-KO mice) exacerbated stress-induced neuroinflammatory responses and confirmed that effects of JWH-133 were mediated through CB2 receptors. CONCLUSIONS AND IMPLICATIONS: Pharmacological manipulation of CB2 receptors is a potential therapeutic strategy for the treatment of stress-related pathologies with a neuroinflammatory component, such as depression.

Extensive sequence analysis of CFTR, SCNN1A, SCNN1B, SCNN1G and SERPINA1 suggests an oligogenic basis for cystic fibrosis-like phenotypes.

The term cystic fibrosis (CF)-like disease is used to describe patients with a borderline sweat test and suggestive CF clinical features but without two CFTR(cystic fibrosis transmembrane conductance regulator) mutations. We have performed the extensive molecular analysis of four candidate genes (SCNN1A, SCNN1B, SCNN1G and SERPINA1) in a cohort of 10 uncharacterized patients with CF and CF-like disease. We have used whole-exome sequencing to characterize mutations in the CFTR gene and these four candidate genes. CFTR molecular analysis allowed a complete characterization of three of four CF patients. Candidate variants in SCNN1A, SCNN1B, SCNN1G and SERPINA1 in six patients with CF-like phenotypes were confirmed by Sanger sequencing and were further supported by in silico predictive analysis, pedigree studies, sweat test in other family members, and analysis in CF patients and healthy subjects. Our results suggest that CF-like disease probably results from complex genotypes in several genes in an oligogenic form, with rare variants interacting with environmental factors.

Detection criteria and preventive measures for occupational disease in the mines of Almaden (Spain).

This research focuses on the metallurgy and underground mining job positions in the historic mines of Almaden (Spain). We introduce a preventive methodology for hydrargyrism in work environments known by the name of Methodology for Operational Units Action Levels for Health Indicators (MUONAIS). The methodology allows critical levels to be established using environmental and clinical-biological indicators. The prevention plan concentrated on 15 job positions in the metallurgy department that employed more than 100 workers between the years 1986 and 1997. The development of this preventive methodology managed to keep workers' mercury levels below 60 µg/l in blood and 200 µg/l in urine, values that present no negative effects on human health. MUONAIS has proven very effective in protecting workers' health. During this period, some cases of micro-mercurialism were detected, yet were completely reversible, allowing us to affirm that the terrible disease of hydrargyrism was totally eradicated.

Clinical value of a single determination of intracellular ATP levels in stimulated CD4+ T lymphocytes in pediatric patients with stable liver transplantation.

In the follow-up of transplanted patients under immunosupression, the functional assessment of CD4+ T cells activation by measuring intracellular ATP levels in vitro, using the Immuknow test give information on how immune system is functioning. Therefore, it has been reported that low levels of ATP correlate with the risk of opportunistic infection. Although limited, comprehensive results in adult recipients as well as in pediatric transplanted patients have been reported. Forty stable liver pediatric transplanted patients (mean age: 11.0 years [SD 5.65]), within at least 1 year of transplant were selected for a scheduled review, and an unique determination of Immuknow was performed. Average ATP levels were 317 ng/mL (200-400 ng/mL) which were similar to the values observed in adult population. ATP values among patients with monotherapy Cyclosporin A (CSA) or tacrolimus (TAC) were significantly higher (P = .005) than in patients with double immunosupressive therapy using either CSA/TAC + Mycophenolate Mofetil (MMF). In CSA treatment, there are significant differences (P = .0003) between monotherapy and double therapy, but in the case of TAC we did not find differences (P > .1). A single determination of levels of ATP on CD4+ lymphocytes, can provide additional information that could be used as a complementary test to guide immunosuppressive therapy in paediatric liver transplant recipients.

Overexpression of cannabinoid CB2 receptor in the brain induces hyperglycaemia and a lean phenotype in adult mice.

It is well known that the endocannabinoid system, through cannabinoid CB1 receptor activation, has an important role in the main aspects of energy balance (i.e. food intake, energy expenditure and glucose and fat metabolism), orchestrating all the machinery involved in body weight control and energy homeostasis. A number of studies have revealed a crucial role of brain CB1 receptors in these processes. However, functional cannabinoid CB2 receptors have also been described in the brain, with no studies addressing their putative role in body weight control and glucose homeostasis. We have tested this hypothesis by analysing fasting-induced feeding, body weight, some hypothalamic neuropeptides, glucose tolerance and plasma hormones in an animal model specifically overexpressing CB2 receptors in the central nervous system. We found that specific overexpression of CB2 receptors in the brain promoted higher basal glucose levels, decreased fasting-induced feeding and, eventually, led to a lean phenotype and glucose intolerance. These findings could not be attributed to decreased locomotor activity, increased anxiety or depressive-like behaviours. The expression of relevant neuropeptides such as pro-opiomelanocortin and galanin in the arcuate nucleus of the hypothalamus was altered but not those of the CB1 receptor. Indeed, no changes in CB1 expression were found in the liver, skeletal muscle and adipose tissue. However, cannabinoid CB1 and CB2 receptor expression in the endocrine pancreas and glucagon plasma levels were decreased. No changes in plasma adiponectin, leptin, insulin and somatostatin were found. Taken together, these results suggest a role for central cannabinoid CB2 receptors in body weight control and glucose homeostasis.

Pancreatitis en la fibrosis quística: correlación con el genotipo y estado pancreático / Pancreatitis in cystic fibrosis: association with genotype and pancreatic status

Introducción: La pancreatitis es una rara complicación en la evolución de pacientes con fibrosis quística (FQ). Puede presentarse en forma de episodios agudos, aislados o repetidos, o evolucionar a cronicidad con progresiva destrucción de la glándula. El objetivo de este estudio fue describir las características de una cohorte de pacientes que habían padecido pancreatitis, conocer su frecuencia e intentar encontrar posibles factores de riesgo asociados. Metodología: Estudio retrospectivo descriptivo de pacientes controlados en unidades de FQ de cinco hospitales españoles que habían padecido pancreatitis. Se recogieron datos demográficos, clínicos y analíticos, y relativos al estado pancreático y el genotipo. Resultados: De 520 pacientes, 17 presentaron pancreatitis. Una prevalencia del 3,3%, superior a la descrita en la literatura. Analizando el estado pancreático, se observó que 8 de ellos eran insuficientes pancreáticos (47,06%), hecho que contrasta, en parte, con lo referido clásicamente al considerar esta complicación más típica de pacientes con cierto grado de reserva pancreática. No se encontraron factores de riesgo ni asociaciones significativas con la genética, edad, sexo u otras características. Conclusiones: En nuestra serie, la prevalencia de pancreatitis es superior a la descrita en la literatura, no tratándose de una complicación exclusiva de suficientes pancreáticos. Se produce más frecuentemente durante la adolescencia o en el inicio de la edad adulta. La enfermedad pulmonar es leve en la mayoría. La genética es variable, sin poder establecerse una clara relación genotipo-fenotipo. Se debe observar a largo plazo la evolución de esta patología intercurrente y diseñar estudios más amplios para obtener resultados más significativos (AU)

Introduction: Pancreatitis is an uncommon complication of cystic fibrosis (CF). Either single or recurrent acute episodes can occur and it occasionally may follow a protracted course with relentless destruction of the pancreas. Moreover mild mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) have been found in many cases of idiopathic chronic pancreatitis. We describe a group of patients with CF who had one or more episodes of pancreatitis. We have estimated its prevalence in a large population of patients with CF across Spain. Methods: A retrospective descriptive study was conducted by collecting the demographic, clinical and laboratory data, pancreatic status and genotype of CF patients who attended the CF Units in 5 Spanish hospitals. Results: The overall number of CF patients under follow-up in the five centres was 520, of which 17 cases with pancreatitis were identified. The prevalence of pancreatitis in this population was 3.3%, higher than previously reported. Noticeably eight of the 17 patients (47.06%) had pancreatic insufficiency. This appears to be, partly, in contrast with that classically found, as this complication is usually associated with patients with a certain level of pancreatic reserve. No associations with genotype, age, gender or other factors were found. Conclusions: The prevalence of pancreatitis in our CF patients was higher than that found in other CF populations, and was not limited to patients with pancreatic sufficiency. It occurred mostly in teenagers and young adults often with mild pulmonary disease. The CF genotype was variable. The course of the patients should be carefully monitored, and further information on the long-term outcome of larger cohorts of patients is needed (AU)

[Pancreatitis in cystic fibrosis: association with genotype and pancreatic status]. / Pancreatitis en la fibrosis quística: correlación con el genotipo y estado pancreático.

INTRODUCTION: Pancreatitis is an uncommon complication of cystic fibrosis (CF). Either single or recurrent acute episodes can occur and it occasionally may follow a protracted course with relentless destruction of the pancreas. Moreover mild mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) have been found in many cases of idiopathic chronic pancreatitis. We describe a group of patients with CF who had one or more episodes of pancreatitis. We have estimated its prevalence in a large population of patients with CF across Spain. METHODS: A retrospective descriptive study was conducted by collecting the demographic, clinical and laboratory data, pancreatic status and genotype of CF patients who attended the CF Units in 5 Spanish hospitals. RESULTS: The overall number of CF patients under follow-up in the five centres was 520, of which 17 cases with pancreatitis were identified. The prevalence of pancreatitis in this population was 3.3%, higher than previously reported. Noticeably eight of the 17 patients (47.06%) had pancreatic insufficiency. This appears to be, partly, in contrast with that classically found, as this complication is usually associated with patients with a certain level of pancreatic reserve. No associations with genotype, age, gender or other factors were found. CONCLUSIONS: The prevalence of pancreatitis in our CF patients was higher than that found in other CF populations, and was not limited to patients with pancreatic sufficiency. It occurred mostly in teenagers and young adults often with mild pulmonary disease. The CF genotype was variable. The course of the patients should be carefully monitored, and further information on the long-term outcome of larger cohorts of patients is needed.

Hepatopatías metabólicas / Metabolic liver diseases

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Nutrición artificial en pacientes pediátricos con pancreatitis aguda / Artificial nutrition support in pediatric patient with acute pancreatitis

La pancreatitis aguda es una entidad poco frecuente en niños respecto a los adultos, aunque algunos estudios recientes sugieren un incremento de su incidencia. Una vez estabilizado el paciente, el tratamiento se basa en el soporte nutricional. La escasez de estudios prospectivos realizados en pacientes pediátricos obliga a los clínicos a actuar basándose en guías validadas para los adultos. El objetivo de este trabajo es tratar de revisar los conocimientos sobre el soporte nutricional en pacientes pediátricos con pancreatitis aguda y proponer una guía de actuación en el manejo de estos pacientes (AU)

Acute pancreatitis occurs less frequently in children compared with adults. However, recent studies have suggested that its incidence may be increasing. Once it is diagnosed the treatment of these patients is based on nutrition support. There are few prospective studies in children, therefore the physicians are obliged to use validated adult guides. Our objective is to review the knowledge on nutrition support in pediatric patients with acute pancreatitis and suggest a guide for the management of these patients (AU)

Regulation of Fas receptor/Fas-associated protein with death domain apoptotic complex and associated signalling systems by cannabinoid receptors in the mouse brain.

BACKGROUND AND PURPOSE: Natural and synthetic cannabinoids (CBs) induce deleterious or beneficial actions on neuronal survival. The Fas-associated protein with death domain (FADD) promotes apoptosis, and its phosphorylated form (p-FADD) mediates non-apoptotic actions. The regulation of Fas/FADD, mitochondrial apoptotic proteins and other pathways by CB receptors was investigated in the mouse brain. EXPERIMENTAL APPROACH: Wild-type, CB(1) and CB(2) receptor knock-out (KO) mice were used to assess differences in receptor genotypes. CD1 mice were used to evaluate the effects of CB drugs on canonical apoptotic pathways and associated signalling systems. Target proteins were quantified by Western blot analysis. KEY RESULTS: In brain regions of CB(1) receptor KO mice, Fas/FADD was reduced, but p-Ser191 FADD and the p-FADD/FADD ratio were increased. In CB(2) receptor KO mice, Fas/FADD was increased, but the p-FADD/FADD ratio was not modified. In mutant mice, cleavage of poly(ADP-ribose)-polymerase (PARP) did not indicate alterations in brain cell death. In CD1 mice, acute WIN55212-2 (CB(1) receptor agonist), but not JWH133 (CB(2) receptor agonist), inversely modulated brain FADD and p-FADD. Chronic WIN55212-2 induced FADD down-regulation and p-FADD up-regulation. Acute and chronic WIN55212-2 did not alter mitochondrial proteins or PARP cleavage. Acute, but not chronic, WIN55212-2 stimulated activation of anti-apoptotic (ERK, Akt) and pro-apoptotic (JNK, p38 kinase) pathways. CONCLUSIONS AND IMPLICATIONS: CB(1) receptors appear to exert a modest tonic activation of Fas/FADD complexes in brain. However, chronic CB(1) receptor stimulation decreased pro-apoptotic FADD and increased non-apoptotic p-FADD. The multifunctional protein FADD could participate in the mechanisms of neuroprotection induced by CBs.

Depression-resistant endophenotype in mice overexpressing cannabinoid CB(2) receptors.

BACKGROUND AND PURPOSE: The present study evaluated the role of CB(2) receptors in the regulation of depressive-like behaviours. Transgenic mice overexpressing the CB(2) receptor (CB2xP) were challenged with different types of acute and chronic experimental paradigms to evaluate their response in terms of depressive-like behaviours. EXPERIMENTAL APPROACH: Tail suspension test (TST), novelty-suppressed feeding test (NSFT) and unpredictable chronic mild stress tests (CMS) were carried out in CB2xP mice. Furthermore, acute and chronic antidepressant-like effects of the CB(2) receptor-antagonist AM630 were evaluated by means of the forced swimming test (FST) and CMS, respectively, in wild-type (WT) and CB2xP mice. CB(2) gene expression, brain-derived neurotrophic factor (BDNF) gene and protein expressions were studied in mice exposed to CMS by real-time PCR and immunohistochemistry, respectively. KEY RESULTS: Overexpression of CB(2) receptors resulted in decreased depressive-like behaviours in the TST and NSFT. CMS failed to alter the TST and sucrose consumption in CB2xP mice. In addition, no changes in BDNF gene and protein expression were observed in stressed CB2xP mice. Interestingly, acute administration of AM630 (1 and 3 mg x kg(-1), i.p.) exerted antidepressant-like effects on the FST in WT, but not in CB2xP mice. Chronic administration of AM630 for 4 weeks (1 mg x kg(-1); twice daily, i.p.) blocked the effects of CMS on TST, sucrose intake, CB(2) receptor gene, BDNF gene and protein expression in WT mice. CONCLUSION AND IMPLICATIONS: Taken together, these results suggest that increased CB(2) receptor expression significantly reduced depressive-related behaviours and that the CB(2) receptor could be a new potential therapeutic target for depressive-related disorders.