Monoacylglycerol lipase (MAGL) inhibition attenuates acute lung injury in mice.

Endocannabinoid signaling is terminated by enzymatic hydrolysis, a process that, for 2-Arachidonoylglycerol (2-AG), is mediated by monoacylglycerol lipase (MAGL). The piperidine carbamate, 4-nitrophenyl- 4-(dibenzo[d] [1,3]dioxol-5-yl (hydroxy) methyl) piperidine- 1-carboxylate (JZL184), is a drug that inhibits MAGL and presents high potency and selectivity. Thus, JZL184 increases the levels of 2-AG, an endocannabinoid that acts on the CB1 and CB2 cannabinoid receptors. Here, we investigated the effects of MAGL inhibition, with a single dose (16 mg/kg, intraperitoneally (i.p.)) of JZL184, in a murine model of lipopolysaccharide (LPS) -induced acute lung injury (ALI) 6, 24 and 48 hours after the inflammatory insult. Treatment with JZL184 decreased the leukocyte migration into the lungs as well as the vascular permeability measured through the bronchoalveolar lavage fluid (BAL) and histological analysis. JZL184 also reduced the cytokine and chemokine levels in the BAL and adhesion molecule expression in the blood and BAL. The CB1 and CB2 receptors were considered involved in the anti-inflammatory effects of JZL184 because the AM281 selective CB1 receptor antagonist (1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-N-4-morpholinyl-1H-pyrazole-3-carboxamide) and the AM630 selective CB2 receptor antagonist ([6-iodo-2-methyl-1-[2-(4-morpholinyl)ethyl]-1H-indol-3-yl](4-methoxyphenyl)-methanone) blocked the anti-inflammatory effects previously described for JZL184. It was concluded that MAGL inhibition, and consequently the increase in 2-AG levels, produced anti-inflammatory effects in a murine model of LPS-induced ALI, a finding that was considered a consequence of the activation of the CB1 and CB2 receptors.

Increased cell-mediated immunity in male mice offspring exposed to maternal immune activation during late gestation.

Early life experiences, particularly during the gestational period, are homeostatic determinants for an individual's brain development. However, recent data suggest that the immune response of the offspring is also affected by events during the gestational period. Here, we evaluated the impact of prenatal immune activation on the innate and adaptive immune responses of adult offspring. Pregnant Swiss mice received saline or lipopolysaccharide (LPS) on gestational day 17. In adulthood, male offspring were analyzed using 2 experimental techniques: in vitro analysis of cytokine production and immune cell activity and development of the delayed-type hypersensitivity (DTH) responses of ovalbumin-sensitized mice. We analyzed Th1/Th2/Th17 cytokine production in vitro, neutrophil and dendritic cell function, and the DTH response. Offspring from LPS-treated dams displayed increased cell-mediated immunity as indicated by increased IL-12 production by cultured antigen-presenting cells and an enhanced DTH response as well as impaired production of the regulatory cytokine IL-10. This study provides new insights regarding the influence of immune activation during late gestation on the immunological homeostasis of offspring, particularly on Th1 immunity.

Ativação de receptores nicotínicos modula a atividade de células dendríticas OVA sensibilizadas / Nicotinic receptors activation modulates OVA sensitized dendritic cells activity

A resposta imune pode ser regulada tanto pelo SNS quanto pelo SNP. Estudos recentes têm identificado uma via colinérgica anti-inflamatória entre as fibras eferentes do nervo vago e direcionadas ao sistema imune. Desta forma, tem-se postulado que esta conexão provê um controle neural da inflamação aguda de uma forma direta e reflexa, sendo então chamada de reflexo inflamatório. Assim, pareceu-nos relevante estudar as influências do SNP na função das DCs, o que foi feito na vigência de um processo inflamatório do tipo antígeno específico produzido por OVA. Para tanto utilizamos: o Betanecol (agonista muscarínico), a Atropina (antagonista muscarínico), a Anabasina (agonista nicotínico) e a Mecamilamina (antagonista nicotínico). No presente trabalho observou-se que: A Anabasina aumentou a porcentagem de células que expressam as moléculas co-estimulatórias B7.1 e B7.2 no baço de camundongos e diminuiu a produção de IL-12 no sobrenadante de co-cultura de células de baço, enquanto que o Betanecol não produziu qualquer efeito no fenótipo das DCs e na produção de citocinas; A Mecamilamina e a Atropina não foram capazes de alterar o fenótipo de DCs de baço e nem a produção de citocinas numa co-cultura de células de baço. A Anabasina, por sua vez: diminuiu a expressão das moléculas co-estimulatórias B7.1 e B7.2 nas DCs de linfonodo; diminuiu a expressão de MHC-II e aumentou a expressão das moléculas co-estimulatórias B7.1 e B7.2 em DCs de baço; diminuiu a expressão de IL-12 intracelular e aumentou a expressão de NF-B de DCs de cultura de hepatócitos; diminuiu os níveis séricos de TNF e MCP-1 e aumentou os níveis séricos de IL-6; diminuiu a resposta de 10 hipersensibilidade do tipo tardia; aumentou a expressão de MHC-II, diminuiu a expressão das moléculas co-estimulatórias B7.1 e B7.2; diminuiu a produção de IL-12 e aumentou a produção de IL-10 nas DCs de medula óssea; aumentou a expressão de mNAChRa7 de DCs maduras provenientes de medula óssea.(AU)

Immune responses might be regulated by the SNS and by PNS. Recently, it was shown the existence of a cholinergic anti-inflammatory pathway that connects vagus nerve afferent/efferent fibers to immune system cells within some organs. These connections make possible a neural control of the inflammatory response both throught a direct and reflex mechanism; the so called inflammatory reflex. Therefore, we thougth that it would be relevant to study the influences of PNS on DCs function in an antigen specific inflammatory process induced by OVA. As pharmacological tools: Bethanechol (muscarinic agonist), Atropine (muscarinic antagonist), Anabasine (nicotinic agonist) and Mecamylamine (nicotinic antagonist) were used. We showed that anabasine increased the percentage of splenocytes expressing co-stimulatory molecules (B7.1 and B7.2) and decreased IL-12p40 production in co-cultured (adherent:non-adherent) splenocytes supernatant. Bethanechol had no effects on DCs phenotype and cytokines production whatsoever. Mecamylamine and atropine also had no effects on DCs phenotype and on cytokines production, as well. Anabasine: decreased co-stimulatory molecules (B7.1 and B7.2) expression on DCs present in lymph nodes.Anabasine also decreased MHC-II expression, while increased the co-stimulatory molecules (B7.1 and B7.2) expression on DCs present in the spleen.Additionally, anabasine decreased intracellular IL-12 expression, while increased NF-B expression in splenocytes culture. Interestingly, anabasine decreased both TNF and MCP-1 and increased IL-6 serum levels. Anabasine also decreased a delayed type hypersensitivity (DTH) response in OVA-sensitized mice. Moreover, Anabasine increased both MHC-II expression and 12 IL-10 productions, while decreased both co-stimulatory molecules (B7.1 and B7.2) expression and IL-12 production in bone marrow derived DCs.(AU)

3,4-methylenedioxymethamphetamine (ecstasy) decreases inflammation and airway reactivity in a murine model of asthma.

OBJECTIVE: 3,4-Methylenedioxymethamphetamine (MDMA), or ecstasy, is a synthetic drug used recreationally, mainly by young people. It has been suggested that MDMA has a Th cell skewing effect, in which Th1 cell activity is suppressed and Th2 cell activity is increased. Experimental allergic airway inflammation in ovalbumin (OVA)-sensitized rodents is a useful model to study Th2 response; therefore, based on the Th2 skewing effect of MDMA, we studied MDMA in a model of allergic lung inflammation in OVA-sensitized mice. METHODS: We evaluated cell trafficking in the bronchoalveolar lavage fluid, blood and bone marrow; cytokine production; L-selectin expression and lung histology. We also investigated the effects of MDMA on tracheal reactivity in vitro and mast cell degranulation. RESULTS: We found that MDMA given prior to OVA challenge in OVA-sensitized mice decreased leukocyte migration into the lung, as revealed by a lower cell count in the bronchoalveolar lavage fluid and lung histologic analysis. We also showed that MDMA decreased expression of both Th2-like cytokines (IL-4, IL-5 and IL-10) and adhesion molecules (L-selectin). Moreover, we showed that the hypothalamus-pituitary-adrenal axis is partially involved in the MDMA-induced reduction in leukocyte migration into the lung. Finally, we showed that MDMA decreased tracheal reactivity to methacholine as well as mast cell degranulation in situ. CONCLUSIONS: Thus, we report here that MDMA given prior to OVA challenge in OVA-sensitized allergic mice is able to decrease lung inflammation and airway reactivity and that hypothalamus-pituitary-adrenal axis activation is partially involved. Together, the data strongly suggest an involvement of a neuroimmune mechanism in the effects of MDMA on lung inflammatory response and cell recruitment to the lungs of allergic animals.

Long-term maternal separation differentially alters serum corticosterone levels and blood neutrophil activity in A/J and C57BL/6 mouse offspring.

OBJECTIVES: In this work, we searched for maternal separation effects on serum corticosterone levels and blood neutrophil activity in adult male A/J and C57BL/6 mouse offspring. METHODS: 40 male A/J mice and 40 male C57BL/6 mice were divided within each strain into two groups. Mice in the maternal separation group were separated from their mothers (1 h/day) on postnatal days 0-13. Mice in the control group were left undisturbed. On postnatal day 45, blood was drawn from all mice and used to assess neutrophil activity by flow cytometry and serum corticosterone levels by radioimmunoassay. RESULTS: The results showed that each mouse strain responded differently to maternal separation, but in both cases, serum corticosterone levels were affected. In both strains, adult mice that experienced maternal separation showed lower serum corticosterone levels than control mice. In relation to control mice kept together with their mothers, the levels of serum corticosterone were 72.7 and 36.36% lower in A/J and C57BL/6 mice submitted to maternal separation, respectively. The current findings showed that maternal separation increased neutrophil activity in mice after reaching adulthood. The observed effects, although in the same direction, differed between A/J and C57BL/6 mice. Maternal separation increased both the percentage and intensity of phagocytosis in C57BL/6 mice, but had no effects on A/J mice. Furthermore, maternal separation increased basal and propidium iodide-labeled Staphylococcus aureus-induced oxidative burst in A/J mice but did not affect oxidative burst in C57BL/6 mice. Finally, phorbol myristate acetate-induced oxidative burst increased in both strains. CONCLUSION: These results indicate that early maternal separation increases innate immunity, most likely by modifying hypothalamus-pituitary-adrenal axis activity. This suggests that maternal separation is a good model for stress which produces long-term neuroimmune changes whatever the animal species and strain used.

Efeitos da separação materna sobre o comportamento, a imunidade inata e o crescimento tumoral / Maternal separation effects on the behavior, innate immunity and tumor growth

Um modelo de indução de estresse/ansiedade é a separação materna. Sabe-se, a este respeito, que o desenvolvimento do comportamento emocional normal em mamíferos jovens depende da interação entre a mãe e o filhote. Além disso, eventos estressantes na infância e interrupções no cuidado materno podem levar a efeitos deletérios na resposta imune e na resistência a doenças ao longo da vida. Buscamos neste trabalho estudar os efeitos da separação materna sobre o comportamento, imunidade inata e crescimento tumoral de uma prole de camundongos machos adultos. Nossos resultados mostraram que a separação materna, em camundongos A/J, (1) não produziu alterações robustas no comportamento e em parâmetros hematológicos (antes e após o crescimento tumoral), (2) aumentou a atividade de neutrófilos sanguíneos e macrófagos alveolares (antes e após o crescimento tumoral), (3) aumentou os níveis estriatais de serotonina, seu metabólito 5-HIAA e o turnover de dopamina, (4) diminuiu os níveis séricos de corticosterona e (5) não influenciou a incidência tumoral. Em camundongos C57BL/6, a separação materna produziu um comportamento ansioso e um aumento na atividade de neutrófilos sanguíneos. Tomados em seu conjunto, parece-nos possível afirmar que a separação materna tenha produzido alterações na atividade neuroimune dos animais, modificando, nos mesmos a atividade do eixo HPA e essas alterações foram influenciadas pelas características individuais das linhagens(AU)