RESUMO
After the H7N7 highly pathogenic (HP) avian influenza (AI) outbreak in 2013, and a single case of H5N8 HPAI in 2014, in April 2016, a H7N7 HPAI virus was detected in northeastern Italy. The case occurred in an organic free-range laying hen farm located in proximity with one of the highest densely populated poultry areas (DPPAs) in Italy. Control measures provided by the Council of the European Union in directive 2005/94/CE were promptly applied, and enhanced surveillance activities were implemented in the DPPAs. On May 16, 2016, a second case was confirmed in a fattening turkey farm within the protection zone of the previous outbreak. Following an epidemiologic inquiry, another turkey farm was considered at risk of transmission and was subjected to preemptive culling. Epidemiologic data and phylogenetic analyses indicated that the virus was likely introduced from wild birds as a low pathogenicity AI strain, through direct contact. The rapid containment of the outbreak proves the level of preparedness of the veterinary public health sector in Italy. Nevertheless, the recurrent introductions from wild birds indicate the need of improving both the biosecurity levels in the DPPA and the surveillance activities in wild birds to quickly detect the presence of AI in the territory.
Assuntos
Vírus da Influenza A Subtipo H7N7/isolamento & purificação , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Animais , Animais Selvagens/virologia , Galinhas/crescimento & desenvolvimento , Galinhas/virologia , Surtos de Doenças , Fazendas , Vírus da Influenza A Subtipo H7N7/classificação , Vírus da Influenza A Subtipo H7N7/genética , Vírus da Influenza A Subtipo H7N7/patogenicidade , Influenza Aviária/epidemiologia , Itália/epidemiologia , Filogenia , Doenças das Aves Domésticas/epidemiologia , Perus/crescimento & desenvolvimento , Perus/virologia , VirulênciaRESUMO
Infectious bronchitis is considered to be one of the most devastating diseases in poultry. Control of its spread is typically attempted through biosecurity measures and extensive vaccination. However, the remarkable genetic and antigenic variability of the virus, which originate from both mutations and recombination events, represents an unsolved challenge for this disease. The present study reports on the emergence and spread of recombinant clusters detected in Italy and Spain between 2012 and 2014. A total of 36 Spanish and Italian infectious bronchitis virus (IBV) field strains were investigated and genetically characterized using phylogenetic, molecular, recombination and selection pressure analyses of the complete S1 gene. Based on the partial S1 sequencing, 27 IBV strains originating from Spain and nine from Italy were initially classified as being closely related to the Guandong/Xindadi (XDN) genotype. Phylogenetic analysis of the complete S1 gene revealed that the XDN strains formed a homogeneous clade with the Spanish IBV isolates within the QX genotype, whereas there was higher variability within the Italian strains. Recombination analysis determined that these strains belonged to four groups, which originated from independent recombination events between the QX and 793B IBV genotypes. Our data support the hypothesis of two different scenarios: firstly, in Spain, the large and homogeneous clade probably originated from a single offspring of the recombinant founder, which became dominant and spread throughout the country. Secondly, the nine Italian recombinants, which are characterized by three different recombination patterns, probably represent less fitted strains, because they were less viable with respect to their recombinant parents.
Assuntos
Infecções por Coronavirus/veterinária , Variação Genética , Vírus da Bronquite Infecciosa/genética , Doenças das Aves Domésticas/virologia , Aves Domésticas/virologia , Recombinação Genética , Animais , Embrião de Galinha , Infecções por Coronavirus/virologia , Feminino , Genótipo , Vírus da Bronquite Infecciosa/isolamento & purificação , Itália , Filogenia , Análise de Sequência de RNA , EspanhaRESUMO
AIM: In vitro and in vivo challenge studies were undertaken to develop an in-feed additive of microencapsulated propionic, sorbic acids and pure botanicals to control Campylobacter jejuni in broilers at slaughter age. METHODS AND RESULTS: Organic acids (OA) and pure botanicals were tested in vitro against Camp. jejuni, whereas in vivo, chickens were fed either a control diet, or increasing doses of the additive for 42 days (experiment 1); in the second experiment, chickens received the additive at 0.1 or 0.3% from day 0 to 21 or from day 22 to 42. The additive consistently reduced Camp. jejuni caecal counts at any given dose (exp. 1) or inclusion plan (exp. 2). Moreover, it was able to reduce the number of goblet cells and modify mucin glycoconjugates biosynthesis pattern. CONCLUSIONS: We developed an additive that was effective in reducing Camp. jejuni in slaughter-age chickens even at low doses (0.1%). That efficacy was the result of the synergistic action between OA and botanicals. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a strategy to reduce Camp. jejuni in broilers and, as a consequence, to improve the safety of the food chain. Moreover, data suggest that a treatment limited to the last weeks before slaughter would allow to save on inclusion of the additive throughout the whole production cycle.
Assuntos
Ração Animal , Infecções por Campylobacter/veterinária , Campylobacter jejuni/efeitos dos fármacos , Galinhas/microbiologia , Aditivos Alimentares/farmacologia , Doenças das Aves Domésticas/microbiologia , Animais , Infecções por Campylobacter/microbiologia , Infecções por Campylobacter/patologia , Campylobacter jejuni/crescimento & desenvolvimento , Campylobacter jejuni/isolamento & purificação , Ceco/citologia , Ceco/microbiologia , Eugenol/farmacologia , Mucosa Intestinal/patologia , Doenças das Aves Domésticas/patologia , Propionatos/farmacologia , Ácido Sórbico/farmacologia , Timol/farmacologiaRESUMO
BACKGROUND AND PURPOSE: Several studies have demonstrated anti-proliferative and pro-apoptotic actions of cannabinoids on various tumours, together with their anti-angiogenic properties. The non-psychoactive cannabinoid cannabidiol (CBD) effectively inhibits the growth of different types of tumours in vitro and in vivo and down-regulates some pro-angiogenic signals produced by glioma cells. As its anti-angiogenic properties have not been thoroughly investigated to date, and given its very favourable pharmacological and toxicological profile, here, we evaluated the ability of CBD to modulate tumour angiogenesis. EXPERIMENTAL APPROACH: Firstly, we evaluated the effect of CBD on human umbilical vein endothelial cell (HUVEC) proliferation and viability - through [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay and FACS analysis - and in vitro motility - both in a classical Boyden chamber test and in a wound-healing assay. We next investigated CBD effects on different angiogenesis-related proteins released by HUVECs, using an angiogenesis array kit and an ELISA directed at MMP2. Then we evaluated its effects on in vitro angiogenesis in treated HUVECs invading a Matrigel layer and in HUVEC spheroids embedded into collagen gels, and further characterized its effects in vivo using a Matrigel sponge model of angiogenesis in C57/BL6 mice. KEY RESULTS: CBD induced HUVEC cytostasis without inducing apoptosis, inhibited HUVEC migration, invasion and sprouting in vitro, and angiogenesis in vivo in Matrigel sponges. These effects were associated with the down-modulation of several angiogenesis-related molecules. CONCLUSIONS AND IMPLICATIONS: This study reveals that CBD inhibits angiogenesis by multiple mechanisms. Its dual effect on both tumour and endothelial cells supports the hypothesis that CBD has potential as an effective agent in cancer therapy.
Assuntos
Inibidores da Angiogênese/uso terapêutico , Canabidiol/uso terapêutico , Neovascularização Patológica/tratamento farmacológico , Inibidores da Angiogênese/farmacologia , Animais , Canabidiol/farmacologia , Movimento Celular/efeitos dos fármacos , Heparina , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neovascularização Patológica/induzido quimicamente , Fator de Necrose Tumoral alfa , Fator A de Crescimento do Endotélio VascularRESUMO
In April 2009, a novel H1N1 influenza A virus (pH1N1) was recognized as the cause of the flu pandemic in humans. Here, we report the isolation of pH1N1 virus from the lung homogenates of two cats, which died after severe respiratory symptoms. The cats belonged to a cat colony consisting of 90 caged cats and were found dead following a 2-week period of respiratory and gastrointestinal diseases in the colony. During the outbreak, 25 cats died and 50% of the animal colony showed anorexia, depression, respiratory and gastrointestinal symptoms. Histological examination of the lungs of the two tested cats displayed lesions centred on terminal airways with epithelial bronchiolar hyperplasia and alveolar necrosis. Influenza A virus was detected in the lung tissues by immunohistochemistry and real-time RT-PCR (rRT-PCR). Partial sequences of haemagglutinin (HA) genes and complete sequences of neuraminidase (NA) genes of the two isolates displayed high similarity to the pH1N1 viruses circulating in humans (99% for HA gene and 100% for NA gene). To determine whether the pandemic virus had circulated among cats, serum samples and pharyngeal swabs were collected from 38 cats of the colony. Serum samples were tested by ELISA to detect antibodies against pH1N1 nucleoprotein and by hemagglutination-inhibition test, while pharyngeal swabs were examined by pH1N1 specific rRT-PCR. Twenty-one (55%) of the tested cats carried antibodies against the isolated strain and two swabs were positive for the presence of pH1N1 RNA. Our results confirm that the pH1N1 virus was able to infect cats and raise the hypothesis of the circulation of the virus within the colony being due to cat-to-cat transmission. The case reported here provides, to the best of the authors' knowledge, the first description of the pH1N1 infection involving numerous cats that lived in a restricted area with limited contact with humans.
Assuntos
Doenças do Gato/epidemiologia , Doenças do Gato/virologia , Vírus da Influenza A Subtipo H1N1/isolamento & purificação , Infecções por Orthomyxoviridae/veterinária , Zoonoses/microbiologia , Animais , Autopsia/veterinária , Doenças do Gato/sangue , Doenças do Gato/patologia , Doenças do Gato/transmissão , Gatos , Bases de Dados de Ácidos Nucleicos , Surtos de Doenças/veterinária , Feminino , Imuno-Histoquímica/veterinária , Vírus da Influenza A Subtipo H1N1/genética , Itália/epidemiologia , Pulmão/virologia , Infecções por Orthomyxoviridae/sangue , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/transmissão , Pandemias/veterinária , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Zoonoses/transmissãoRESUMO
The reduction of Salmonella prevalence in broilers is a priority in European Union agricultural policies because treatment with antibiotics is forbidden by Regulation (EC) 2160/2003. Two trials were conducted to evaluate the efficacy of a microencapsulated blend of sorbic acid and nature-identical compounds (i.e., chemically synthesized botanicals; SAB) on the reduction of the cecal prevalence and contents of Salmonella enterica serovars Hadar and Enteritidis in experimentally infected chickens. In the first trial, 125 one-day-old Lohmann specific-pathogen-free chickens were assigned to one of the following treatments: negative control (not challenged and not treated), positive control (challenged and not treated), SAB0.3, SAB1, or SAB5 (challenged and treated with the microencapsulated blend included in the feed at 0.03, 0.1, or 0.5%, respectively). At 30 d of age, birds were infected with 10(6) cfu of Salmonella Hadar, and after 5, 10, or 20 d postinfection, 5, 10, and 10 birds per treatment, respectively, were killed and the cecal contents and liver and spleen samples were analyzed for Salmonella Hadar. In the second trial, 100 one-day-old Ross 708 chickens were assigned to 1 of 5 treatments: control (not treated), SAB0.3, SAB1, SAB2, or SAB5 (treated with the blend included in the feed at 0.03, 0.1, 0.2, or 0.5%, respectively). At 7 d of age, the birds were challenged with 10(5) cfu of Salmonella Enteritidis, and after 7, 14, or 24 d after challenge, 5, 5, and 10 birds per treatment, respectively, were killed and cecal contents were analyzed for Salmonella Enteritidis. Results showed that in the early stage of infection Salmonella prevalence was high in both studies, whereas at the end of the observation periods, the blends at 0.03, 0.1, and 0.5 in the challenge with Salmonella Hadar and at 0.2 and 0.5% in the challenge with Salmonella Enteritidis significantly reduced (by 2 log(10) cfu) the cecal content of Salmonella. This study showed that intestinal delivery of microencapsulated sorbic acid and nature-identical compounds can result in a 100-fold reduction of Salmonella at the intestinal level in broilers at slaughter age.
Assuntos
Produtos Biológicos/uso terapêutico , Galinhas , Doenças das Aves Domésticas/prevenção & controle , Salmonelose Animal/microbiologia , Salmonella/classificação , Ácido Sórbico/uso terapêutico , Ração Animal , Animais , Antibacterianos/administração & dosagem , Antibacterianos/uso terapêutico , Produtos Biológicos/administração & dosagem , Dieta/veterinária , Composição de Medicamentos , Feminino , Salmonelose Animal/prevenção & controle , Ácido Sórbico/administração & dosagemRESUMO
Recently, the presence of functional interaction between the opioid and cannabinoid system has been shown in various pharmacological responses. Although there is an increasing interest for the feasible therapeutic application of a co-administration of cannabinoids and opioids in some disorders (i.e. to manage pain, to modulate immune system and emotions) and the combined use of the two drugs by drug abusers is becoming largely diffuse, only few papers focused on cellular and molecular mechanisms underlying this interaction. This review updates the biochemical and molecular underpinnings of opioid and cannabinoid interaction, both within the central nervous system and periphery. The most convincing theory for the explanation of this reciprocal interaction involves (i) the release of opioid peptides by cannabinoids or endocannabinoids by opioids, (ii) the existence of a direct receptor-receptor interaction when the receptors are co-expressed in the same cells, and (iii) the interaction of their intracellular pathways. Finally, the cannabinoid/opioid interaction might be different in the brain rewarding networks and in those accounting for other pharmacological effects (antinociception, modulation of emotionality and cognitive behavior), as well as between the central nervous system and periphery. Further insights about the cannabinoid/opioid interaction could pave the way for new and promising therapeutic approaches.
Assuntos
Analgésicos Opioides/uso terapêutico , Encéfalo/efeitos dos fármacos , Canabinoides/uso terapêutico , Dor/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Analgésicos Opioides/efeitos adversos , Animais , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Moduladores de Receptores de Canabinoides/metabolismo , Canabinoides/efeitos adversos , Cognição/efeitos dos fármacos , Interações Medicamentosas , Emoções/efeitos dos fármacos , Humanos , Sistema Imunitário/efeitos dos fármacos , Sistema Imunitário/metabolismo , Peptídeos Opioides/metabolismo , Transtornos Relacionados ao Uso de Opioides/etiologia , Transtornos Relacionados ao Uso de Opioides/metabolismo , Dor/metabolismo , Dor/fisiopatologia , Receptor Cross-Talk , Receptores de Canabinoides/efeitos dos fármacos , Receptores de Canabinoides/metabolismo , Receptores Opioides/efeitos dos fármacos , Receptores Opioides/metabolismo , Recompensa , Síndrome de Abstinência a Substâncias/metabolismoRESUMO
It has been recently reported that cannabidiol (CBD), a non-psychoactive cannabinoid, is able to kill glioma cells, both in vivo and in vitro, independently of cannabinoid receptor stimulation. However, the underlying biochemical mechanisms were not clarified. In the present study, we performed biochemical analysis of the effect of CBD both in vivo, by using glioma tumor tissues excised from nude mice, and in vitro, by using U87 glioma cells. In vivo exposure of tumor tissues to CBD significantly decreased the activity and content of 5-lipoxygenase (LOX, by approximately 40%), and of its end product leukotriene B4 ( approximately 25%). In contrast cyclooxygenase (COX)-2 activity and content, and the amount of its end product prostaglandin E2, were not affected by CBD. In addition, in vivo treatment with CBD markedly stimulated ( approximately 175%) the activity of fatty acid amide hydrolase (FAAH), the main anandamide-degrading enzyme, while decreasing anandamide content ( approximately 30%) and binding to CB1 cannabinoid receptors ( approximately 25%). In vitro pre-treatment of U87 glioma cells with MK-886, a specific 5-LOX inhibitor, significantly enhanced the antimitotic effect of CBD, whereas the pre-treatment with indomethacin (pan-COX inhibitor) or celecoxib (COX-2 inhibitor), did not alter CBD effect. The study of the endocannabinoid system revealed that CBD was able to induce a concentration-dependent increase of FAAH activity in U87 cells. Moreover, a significantly reduced growth rate was observed in FAAH-over-expressing U87 cells, compared to wild-type controls. In conclusion, the present investigation indicates that CBD exerts its antitumoral effects through modulation of the LOX pathway and of the endocannabinoid system, suggesting a possible interaction of these routes in the control of tumor growth.
Assuntos
Amidoidrolases/fisiologia , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Araquidonato 5-Lipoxigenase/fisiologia , Canabidiol/metabolismo , Canabidiol/farmacologia , Animais , Canabinoides/metabolismo , Canabinoides/farmacologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Feminino , Humanos , Camundongos , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto/métodosRESUMO
There is a general consensus that the effects of cannabinoid agonists on anxiety seem to be biphasic, with low doses being anxiolytic and high doses ineffective or possibly anxiogenic. Besides the behavioural effects of cannabinoids on anxiety, very few papers have dealt with the neuroanatomical sites of these effects. We investigated the effect on rat anxiety behavior of local administration of THC in the prefrontal cortex, basolateral amygdala and ventral hippocampus, brain regions belonging to the emotional circuit and containing high levels of CB1 receptors. THC microinjected at low doses in the prefrontal cortex (10 microg) and ventral hippocampus (5 microg) induced in rats an anxiolytic-like response tested in the elevated plus-maze, whilst higher doses lost the anxiolytic effect and even seemed to switch into an anxiogenic profile. Low THC doses (1 microg) in the basolateral amygdala produced an anxiogenic-like response whereas higher doses were ineffective. All these effects were CB1-dependent and closely linked to modulation of CREB activation. Specifically, THC anxiolytic activity in the prefrontal cortex and ventral hippocampus was paralleled by an increase in CREB activation, whilst THC anxiogenic response in the basolateral amygdala was paralleled by a decrease in CREB activation. Our results suggest that while a mild activation of CB1 receptors in the prefrontal cortex and ventral hippocampus attenuates anxiety, a slight CB1 receptor stimulation in the amygdala results in an anxiogenic-like response. The molecular underpinnings of these effects involve a direct stimulation of CB1 receptors ending in pCREB modulation and/or a possible alteration in the fine tuning of local neuromodulator release.
Assuntos
Ansiedade/patologia , Ansiedade/fisiopatologia , Encéfalo/fisiopatologia , Receptor CB1 de Canabinoide/fisiologia , Tonsila do Cerebelo/efeitos dos fármacos , Analgésicos não Narcóticos , Análise de Variância , Animais , Ansiedade/tratamento farmacológico , Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Proteína de Ligação a CREB/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Dronabinol/uso terapêutico , Hipocampo/efeitos dos fármacos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Microinjeções/métodos , Atividade Motora/efeitos dos fármacos , Piperidinas/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Pirazóis/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/efeitos dos fármacos , Fatores de TempoRESUMO
How cannabinoids influence immune function has been examined extensively in the last 30 years. Studies on drug-abusing humans and animals, as well as in vitro models employing immune cell cultures, have shown that marijuana, natural and endogenous cannabinoid compounds are immunomodulators. These substances modulate host resistance to bacterial, protozoan and viral infections as well as they can profoundly affect the Th1/Th2 response. Recently, two types of cannabinoid receptor, CB1 and CB2, have been discovered. While CB1 is expressed primarily in the brain, CB2 is peculiar of the immune cells. Cannabinoid receptors have been shown to be involved in some but not all of immune effects. Nevertheless, their identification provides a specific mechanism of action in the attempting to find out how exogenous cannabinoids and endogenous cannabinoid system affect the immune apparatus, strengthen the hypothesis of cannabinoids as immunomodulators. As support to this theory, enough evidence exists to suggest that the cannabinoid system significantly affects almost every component of the immune response machinery and impacts the functioning also of the cytokine network. The evaluation of the biological consequences of these drug-induced cytokine changes has also dramatically become important considering not only the impact of cytokines on immune system per se but also envisaging their influence in cancer, inflammation, autoimmune disease, brain injury, hematopoietic colony formation in which cannabinoids have demonstrated a clear role as important modulators.
Assuntos
Canabinoides/farmacologia , Citocinas/fisiologia , Sistema Imunitário/efeitos dos fármacos , Animais , Canabinoides/química , Humanos , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Modelos Biológicos , Estrutura Molecular , Transdução de Sinais/efeitos dos fármacosRESUMO
Recently, we have shown that the non-psychoactive cannabinoid compound cannabidiol (CBD) induces apoptosis of glioma cells in vitro and tumor regression in vivo. The present study investigated a possible involvement of caspase activation and reactive oxygen species (ROS) induction in the apoptotic effect of CBD. CBD produced a gradual, time-dependent activation of caspase-3, which preceded the appearance of apoptotic death. In addiction, release of cytochrome c and caspase-9 and caspase-8 activation were detected. The exposure to CBD caused in glioma cells an early production of ROS, depletion of intracellular glutathione and increase activity of glutathione reductase and glutathione peroxidase enzymes. Under the same experimental condition, CBD did not impair primary glia. Thus, we found a different sensitivity to the anti-proliferative effect of CBD in human glioma cells and non-transformed cells that appears closely related to a selective ability of CBD in inducing ROS production and caspase activation in tumor cells.
Assuntos
Canabidiol/farmacologia , Caspases/metabolismo , Glioma/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Células Cultivadas , Ativação Enzimática , Glutationa/metabolismo , HumanosRESUMO
The pharmacokinetics and intramuscular (IM) bioavailability of flumequine (15 mgkg(-1)) were investigated in healthy pigs and the findings related to published minimal inhibitory concentrations (MICs) for susceptible bacteria of animal origin, and to experimentally determined MICs for susceptible strains of porcine origin. We found MICs for Escherichia coli, Salmonella spp., Pasteurella spp. and Bordetella spp. in the range 0.5 to >64 microg mL(-1) isolated from infected pigs in the Forli area of Italy; only the Pasteurella multocida strains were sensitive (MIC(90)=0.5 microg mL(-1)). After intravenous (IV) injection, flumequine was slowly distributed and eliminated (t(1/2lambda(1))1.40+/-0.16 h and t(1/2lambda(2))6.35+/-1.69 h). The distribution volume at steady state (V(dss)) was 752.59+/-84.03 mL kg(-1) and clearance (Cl(B)) was 237.19+/-17.88 mL kg(-1)h(-1). After IM administration, peak serum concentration (4.99+/-0.92 microg mL(-1)) was reached between the 2nd and the 3rd hour. The results on MIC of isolated bacteria, although only indicative, suggest that the efficacy of flumequine on Gram-negative bacteria may be impaired by the emergence of less sensitive or resistant strains.
Assuntos
Fluoroquinolonas/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Suínos/metabolismo , Animais , Área Sob a Curva , Estudos Cross-Over , Escherichia coli/efeitos dos fármacos , Feminino , Fluoroquinolonas/administração & dosagem , Fluoroquinolonas/sangue , Fluoroquinolonas/farmacocinética , Injeções Intramusculares/veterinária , Injeções Intravenosas/veterinária , Masculino , Testes de Sensibilidade Microbiana , Pasteurella/efeitos dos fármacos , Pneumonia Bacteriana/tratamento farmacológico , Pneumonia Bacteriana/veterinária , Salmonella/efeitos dos fármacos , Doenças dos Suínos/tratamento farmacológico , Doenças dos Suínos/microbiologiaRESUMO
Cannabidiol is the main nonpsychoactive component of marijuana. We examined the ability of in vivo and in vitro cannabidiol to interfere with the production of interleukin (IL)-12 and IL-10 by murine macrophages and to modulate macrophage chemotaxis. Cannabidiol added in vitro to peritoneal macrophages significantly increased IL-12 and decreased IL-10 production. The CB1 and CB2 receptor antagonists prevented this modulation. Macrophages from animals treated with cannabidiol at the dose of 30 mg kg(-1) either orally or i.p. produced higher levels of IL-12 and lower levels of IL-10 in comparison to controls, and the CB receptor antagonists did not prevent these effects. Cannabidiol dose-dependently decreased fMLP-induced chemotaxis of macrophages, and the CB2 receptor antagonist prevented this decrease.
Assuntos
Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Canabidiol/administração & dosagem , Canabidiol/farmacologia , Quimiotaxia/efeitos dos fármacos , Interleucina-10/biossíntese , Interleucina-12/biossíntese , Macrófagos Peritoneais/efeitos dos fármacos , Adjuvantes Imunológicos/metabolismo , Administração Oral , Animais , Canfanos/farmacologia , Canabidiol/metabolismo , Inibição de Migração Celular , Células Cultivadas , Quimiotaxia/imunologia , Citocinas/biossíntese , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/imunologia , Interleucina-10/antagonistas & inibidores , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/imunologia , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/metabolismo , Masculino , Camundongos , Piperidinas/farmacologia , Pirazóis/farmacologia , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB1 de Canabinoide/fisiologia , Receptor CB2 de Canabinoide/antagonistas & inibidores , Receptor CB2 de Canabinoide/fisiologia , Rimonabanto , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/imunologiaRESUMO
We used a previously reported model of morphine sensitization that elicited a complex behavioral syndrome involving stereotyped and non stereotyped activity. To identify the mechanism of these long-lasting processes, we checked the density of mu opioid receptors, receptor-G-protein coupling and the cyclic AMP (cAMP) cascade. In morphine-sensitized animals mu opioid receptor autoradiography revealed a significant increase in the caudate putamen (30% versus controls), nucleus accumbens shell (16%), prefrontal and frontal cortex (26%), medial thalamus (43%), hypothalamus (200%) and central gray (89%). Concerning morphine's activation of G proteins in the brain, investigated in the guanylyl 5'-[gamma-(35)S]thio]triphosphate ([(35)S]GTPgammaS) binding assay, a significant increase in net [(35)S]GTPgammaS binding was seen in the caudate putamen (39%) and hypothalamus (27%). In the caudate putamen this was due to an increase in the amount of activated G proteins, and in the hypothalamus to a greater affinity of G proteins for guanosine triphosphate (GTP). The main second messenger system linked to the opioid receptor is the cAMP pathway. In the striatum basal cAMP levels were significantly elevated in sensitized animals (70% versus controls) and [D-Ala(2), N-Me-Phe(4), Gly(5)-ol]-enkephalin (DAMGO) significantly inhibited forskolin-stimulated cAMP production in control (30%) but not in sensitized rats. In the hypothalamus no significant changes were observed in basal cAMP levels and DAMGO inhibition. These cellular events induced by morphine pre-exposure could underlie the neuroadaptive processes involved in morphine sensitization.
Assuntos
Química Encefálica/fisiologia , Encéfalo/efeitos dos fármacos , Morfina/farmacologia , Neurônios/efeitos dos fármacos , Transtornos Relacionados ao Uso de Opioides/metabolismo , Receptores Opioides mu/efeitos dos fármacos , Receptores Opioides mu/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Ligação Competitiva/fisiologia , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Química Encefálica/efeitos dos fármacos , AMP Cíclico/metabolismo , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Proteínas de Ligação ao GTP/efeitos dos fármacos , Proteínas de Ligação ao GTP/metabolismo , Guanosina 5'-O-(3-Tiotrifosfato) , Masculino , Neurônios/metabolismo , Transtornos Relacionados ao Uso de Opioides/fisiopatologia , Ensaio Radioligante , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologiaRESUMO
We investigated the cellular events linked to the induction of cannabinoid behavioural sensitization. In sensitized rats, autoradiographic binding studies with [3H]CP-55,940 showed a significant increase in cannabinoid receptor binding, specifically in the cerebellum, with no changes in the other brain areas where basal CB1-receptor expression is observed. In vitro autoradiography of CP-55,940-stimulated [35S]GTP gamma S binding provided a picture of cannabinoid receptor-mediated G protein activation. Basal [35S]GTP gamma S binding was not affected, whereas sensitized rats showed a significant increase of net [35S]GTP gamma S binding in the caudate putamen and cerebellum. Autoradiographic studies suggested that only these two areas had altered receptor functionality. We therefore focused our intracellular investigations only there, first surveying the responsiveness of the cAMP system to cannabinoids. CP-55,940 was unable to inhibit forskolin-induced cAMP accumulation in the cerebellum of sensitized animals, but no difference was observed between groups in the caudate putamen. Finally, we surveyed the levels of CREB and AP-1 binding activity, in the same two areas and found no difference in sensitized rats. The intracellular picture in sensitized rats suggests that besides the cAMP cascade, other signalling pathways may participate in the development of cannabinoid sensitization.
Assuntos
Encéfalo/efeitos dos fármacos , Dronabinol/farmacologia , Tolerância a Medicamentos/fisiologia , Psicotrópicos/farmacologia , Receptores de Droga/metabolismo , Animais , Autorradiografia , Encéfalo/metabolismo , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/efeitos dos fármacos , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Proteínas de Ligação ao GTP/efeitos dos fármacos , Proteínas de Ligação ao GTP/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley , Receptores de Canabinoides , Radioisótopos de Enxofre , Fator de Transcrição AP-1/efeitos dos fármacos , Fator de Transcrição AP-1/metabolismoRESUMO
The present review focuses on the role of the endogenous cannabinoid system in the modulation of immune response and control of cancer cell proliferation. The involvement of cannabinoid receptors, endogenous ligands and enzymes for their biosynthesis and degradation, as well as of cannabinoid receptor-independent events is discussed. The picture arising from the recent literature appears very complex, indicating that the effects elicited by the stimulation of the endocannabinoid system are strictly dependent on the specific compounds and cell types considered. Both the endocannabinoid anandamide and its congener palmitoylethanolamide, exert a negative action in the onset of a variety of parameters of the immune response. However, 2-arachidonoylglycerol appears to be the true endogenous ligand for peripheral cannabinoid receptors, although its action as an immunomodulatory molecule requires further characterization. Modulation of the endocannabinoid system interferes with cancer cell proliferation either by inhibiting mitogenic autocrine/paracrine loops or by directly inducing apoptosis; however, the proapoptotic effect of anandamide is not shared by other endocannabinoids and suggests the involvement of non-cannabinoid receptors, namely the VR1 class of vanilloid receptors. In conclusion, further investigations are needed to elucidate the function of endocannabinoids as immunosuppressant and antiproliferative/cytotoxic agents. The experimental evidence reviewed in this article argues in favor of the therapeutic potential of these compounds in immune disorders and cancer.
Assuntos
Canabinoides/metabolismo , Eicosanoides/metabolismo , Sistema Imunitário/imunologia , Neoplasias/metabolismo , Animais , Moduladores de Receptores de Canabinoides , Canabinoides/biossíntese , Canabinoides/farmacologia , Divisão Celular/efeitos dos fármacos , Eicosanoides/biossíntese , Eicosanoides/farmacologia , Endocanabinoides , Humanos , Sistema Imunitário/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Receptores de Canabinoides , Receptores de Droga/agonistas , Receptores de Droga/metabolismo , Transdução de Sinais/efeitos dos fármacosRESUMO
Here we describe, for the first time, the occurrence of behavioural sensitization after chronic exposure to Delta9-tetrahydrocannabinol. Rats were treated twice a day, for five days, with increasing doses (5, 10, 20, 40, 40 mg/kg i.p.) of Delta9-tetrahydrocannabinol or its vehicle and after 20 days of withdrawal, animals were challenged with 5 mg/kg (i.p.) of the drug and their behaviour was assessed. Contrary to the motor inhibition induced in control rats, challenge with Delta9-tetrahydrocannabinol in pre-exposed animals elicited a complex behavioural syndrome mainly characterized by oral stereotyped items. Due to the relevance of behavioural sensitization in drug-seeking behaviour that persists long after discontinuation of drug use, our findings suggest that cannabinoids could trigger neurobiological alteration not dissimilar from those observed with more harmful abused drugs.
Assuntos
Comportamento Animal/efeitos dos fármacos , Dronabinol/análogos & derivados , Dronabinol/farmacologia , Abuso de Maconha/fisiopatologia , Animais , Relação Dose-Resposta a Droga , Masculino , Ratos , Ratos Sprague-Dawley , Comportamento Estereotipado/efeitos dos fármacos , Síndrome de Abstinência a Substâncias/fisiopatologiaRESUMO
In the present work, we investigated in the rat the possibility of functional interaction between opiate and cannabinoid systems at immune level comparatively with the central nervous system (CNS). Moderate analgesic doses of the synthetic cannabinoid compound CP-55,940 (0.2 mg/kg, i.p.) and morphine (5 mg/kg, s.c.) significantly inhibited the ConA-induced splenocyte proliferation and natural killer (NK) cytolytic activity. The acute co-administration of the two drugs resulted in an enhancement of antinociception while they did not yield any additive inhibition of the immune parameters. The CB1 cannabinoid receptor antagonist N-(Piperidin-1-yl)-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide (SR141716A; 3 mg/kg, i.p.) and the CB2 receptor antagonist N-[(1S)-endo-1,3,3-trimethhyl bicyclo[2.2.1]heptan-2-yl]-5-(4-chloro-3-methylphenyl)-1-(4-methylbenzyl)-pyrazole-3-carboxamide (SR144528; 3 mg/kg, i.p.) did not block the central nor the immune effects of morphine; similarly, the opioid receptor antagonist naloxone did not attenuate CP-55,940-induced effects. Animals tolerant to CP-55,940-induced (0.2 mg/kg, i.p.; twice a day for 4 days) or morphine-induced analgesia (5 mg/kg, s.c.; twice a day for 6 days) also developed tolerance to their acute immunosuppressive effects. Concomitantly, animals became cross-resistant to the immunosuppressive effects while an asymmetric cross-tolerance developed for analgesia. Our data demonstrated the existence of an interaction between cannabinoids and opiates at the immune level that differs from the interaction present in the CNS.
Assuntos
Analgésicos/farmacologia , Canabinoides/farmacologia , Imunossupressores/farmacologia , Entorpecentes/farmacologia , Animais , Cicloexanóis/farmacologia , Interações Medicamentosas , Tolerância a Medicamentos , Masculino , Morfina/farmacologia , Ratos , Ratos Sprague-DawleyRESUMO
Thirty-six representative velogenic strains of Newcastle disease virus isolated in Italy since 1960 were characterized by restriction site and partial sequence analyses of the fusion protein gene. Viruses belonging to the six known genotypes of Lomniczi et al . were found. Genotype IV, which was most probably the main epizootic group in Europe before the war, was responsible for outbreaks in the 1960s and persisted until the late 1980s in Italy. An epizootic peak in 1972 to 1974 coincided with the appearance of genotype V viruses that were present for more than a decade. Outbreaks in 1992 were caused by genotype VIIa viruses and were part of a contemporaneous epizootic of Far East origin that affected Western European countries. The Newcastle disease epizootic that commenced in Italy in May 2000 was due to a genotype VIIb virus that is indistinguishable from those causing sporadic outbreaks in Great Britain and Northern Europe in the late 1990s. Isolated cases yielded a variant of genotype VI (reference epizootic: Middle East in the late 1960s) and a group VIII virus (enzootic in South Africa).