Vasoactive intestinal peptide suppresses the NLRP3 inflammasome activation in lipopolysaccharide-induced acute lung injury mice and macrophages.

Vasoactive intestinal peptide (VIP) is a neuropeptide that exerts anti-inflammatory functions. We have reported that VIP mediated by lentivirus attenuates acute lung injury (ALI) in lipopolysaccharide (LPS)-induced murine model. However, the exact role of VIP in uncontrolled inflammation during ALI is largely unknown. Accumulating evidence indicates that the NLRP3 inflammasome has a critical role during ALI. In this study, we investigated the effects of VIP on the activation of NLRP3 inflammasome during the development of ALI in mice. Seven days after the intratracheal injection of VIP-lentivirus, a murine ALI model was induced by intratracheal injection of LPS. VIP-lentivirus significantly reduced the expression of NLRP3 inflammasome components in lung tissue, including NLRP3, pro-caspase-1, pro-IL-1β, and pro-IL-18. VIP-lentivirus also inhibited the formation of caspase-1 p10 and the maturation of IL-1β and IL-18. In vitro, exogenous VIP pre-treatment inhibited the priming of NLRP3 inflammasome in murine primary peritoneal macrophages, indicated by down-regulation of expression of NLRP3 inflammasome components. VIP pre-treatment effectively prevented the LPS-induced degradation of I-κB and the synthesis of the downstream of NF-κB, including TNF-α and IL-17A. Furthermore, VIP pre-treatment pronouncedly suppressed the autoproteolysis of caspase-1 and the secretion of IL-1β and IL-18 induced by LPS plus ATP in macrophages. In addition, VIP inhibited the generation of reactive oxygen species in macrophages by decreasing NOX1 and NOX2 expression. These findings illustrate one mechanism that VIP attenuates ALI induced by LPS through inhibiting the activation of the NLRP3 inflammasome and encourage further studies assessing the therapeutic potential of VIP to ALI.

Zhou Y ，Zhang CY ，Duan JX ，Li Q ，Yang HH ，Sun CC ，Zhang J ，Luo XQ ，Liu SK ... -  《-》

Blocking triggering receptor expressed on myeloid cells-1 attenuates lipopolysaccharide-induced acute lung injury via inhibiting NLRP3 inflammasome activation.

Liu T ，Zhou Y ，Li P ，Duan JX ，Liu YP ，Sun GY ，Wan L ，Dong L ，Fang X ，Jiang JX ，Guan CX ... -  《Scientific Reports》

Aloin suppresses lipopolysaccharide-induced acute lung injury by inhibiting NLRP3/NF-κB via activation of SIRT1 in mice.

Lei J ，Shen Y ，Xv G ，Di Z ，Li Y ，Li G ... -  《-》

Pirfenidone ameliorates lipopolysaccharide-induced pulmonary inflammation and fibrosis by blocking NLRP3 inflammasome activation.

Acute respiratory distress syndrome(ARDS)is a severe clinical disorder characterized by its acute onset, diffuse alveolar damage, intractable hypoxemia, and non-cardiogenic pulmonary edema. Acute lung injury(ALI) can trigger persistent lung inflammation and fibrosis through activation of the NLRP3 inflammasome and subsequent secretion of mature IL-1β, suggesting that the NLRP3 inflammasome is a potential therapeutic target for ALI, for which new therapeutic approaches are needed. Our present study aims to assess whether pirfenidone,with anti-fibrotic and anti-inflammatory properties, can improve LPS-induced inflammation and fibrosis by inhibiting NLRP3 inflammasome activation. Male C57BL/6 J mice were intratracheally injected with LPS to induce ALI. Mice were administered pirfenidone by oral gavage throughout the entire experimental course. The mouse macrophage cell line (J774 A.1) was incubated with LPS and ATP, with or without PFD pre-treatment. We demonstrated that PFD remarkably ameliorated LPS-induced pulmonary inflammation and fibrosis and reduced IL-1β and TGF-β1 levels in bronchoalveolar lavage fluid(BALF). Pirfenidone substantially reduced NLRP3 and ASC expression and inhibited caspase-1 activation and IL-1β maturation in lung tissues. In vitro, the experiments revealed that PFD significantly suppressed LPS/ATP-induced production of reactive oxygen species (ROS) and decreased caspase-1 activation and the level of IL-1β in J774 A.1 cells. Taken together, the administration of PFD reduced LPS-induced lung inflammation and fibrosis by blocking NLRP3 inflammasome activation and subsequent IL-1β secretion. These findings indicated that PFD can down-regulate NLRP3 inflammasome activation and that it may offer a promising therapeutic approach for ARDS patients.

Li Y ，Li H ，Liu S ，Pan P ，Su X ，Tan H ，Wu D ，Zhang L ，Song C ，Dai M ，Li Q ，Mao Z ，Long Y ，Hu Y ，Hu C ... -  《-》

Resveratrol ameliorates LPS-induced acute lung injury via NLRP3 inflammasome modulation.

NLRP3 inflammasome plays a pivotal role in the development of acute lung injury (ALI), accelerating IL-1β and IL-18 release and inducing lung inflammation. Resveratrol, a natural phytoalexin, has anti-inflammatory properties via inhibition of oxidation, leukocyte priming, and production of inflammatory mediators. In this study, we aimed to investigate the effect of resveratrol on NLRP3 inflammasome in lipopolysaccharide-induced ALI. Mice were intratracheally instilled with 3mg/kg lipopolysaccharide (LPS) to induce ALI. Resveratrol treatment alleviated the LPS-induced lung pathological damage, lung edema and neutrophil infiltration. In addition, resveratrol reversed the LPS-mediated elevation of IL-1β and IL-18 level in the BAL fluids. In lung tissue, resveratrol also inhibited the LPS-induced NLRP3, ASC, caspase-1 mRNA and protein expression, and NLRP3 inflammasome activation. Moreover, resveratrol administration not only suppressed the NF-κB p65 nuclear translocation, NF-κB activity and ROS production in the LPS-treated mice, but also inhibited the LPS-induced thioredoxin-interacting protein (TXNIP) protein expression and interaction of TXNIP-NLRP3 in lung tissue. Meanwhile, resveratrol obviously induced SIRT1 mRNA and protein expression in the LPS-challenged mice. Taken together, our study suggests that resveratrol protects against LPS-induced lung injury by NLRP3 inflammasome inhibition. These findings further suggest that resveratrol may be of great value in the treatment of ALI and a potential and an effective pharmacological agent for inflammasome-relevant diseases.

Jiang L ，Zhang L ，Kang K ，Fei D ，Gong R ，Cao Y ，Pan S ，Zhao M ，Zhao M ... -  《-》