Inhibition of cyclooxygenase-2 ameliorates the severity of pancreatitis and associated lung injury

Cyclooxygenase-2 (COX-2), a widely distributed enzyme, plays an important role in inflammation. We have studied the role of COX-2 in acute pancreatitis and pancreatitis-associated lung injury using both the pharmacological inhibition of COX-2 and genetic deletion of COX-2. Pancreatitis was induced in mice by 12 hourly injections of cerulein. The severity of pancreatitis was assessed by measuring serum amylase, pancreatic trypsin activity, intrapancreatic sequestration of neutrophils, and acinar cell necrosis. The severity of lung injury was evaluated by measuring lactate dehydrogenase levels in the bronchoalveolar lavage fluid and by quantitating neutrophil sequestration in the lung. In both the pharmacologically inhibited and genetically altered mice, the severity of pancreatitis and pancreatitis-associated lung injury was reduced compared with the noninhibited strains of COX-2-sufficient mice. This reduction in injury indicates that COX-2 plays an important proinflammatory role in pancreatitis and its associated lung injury. Our findings support the concept that COX-2 inhibitors may play a beneficial role in the prevention of acute pancreatitis or in the reduction of its severity.     

Involvement of thrombopoietin in acinar cell necrosis in l-arginine-induced acute pancreatitis in mice

Thrombopoietin (TPO) plays an important role in injuries of different tissues. However, the role of TPO in acute pancreatitis (AP) is not yet known. The aim of the study was to determine the involvement of TPO in AP. Serum TPO was assayed in necrotizing pancreatitis induced by l-arginine in mice. Recombinant TPO and anti-TPO antibody were given to mice with necrotizing pancreatitis. Amylase, lipase, lactate dehydrogenase, myeloperoxidase activity and pancreatic water content were assayed in serum and tissue samples. Pancreas and lung tissue samples were also collected for histological evaluation. Immunohistochemistry of amylase α and PCNA were applied for the study of acinar regeneration and TUNEL assay for the detection of apoptosis in the pancreas. Increased levels of serum TPO were found in necrotizing pancreatitis. After TPO administration, more severe acinar necrosis was found and blockade of TPO reduced the acinar necrosis in this AP model. Acinar regeneration and apoptosis in the pancreas were affected by TPO and antibody treatment in necrotizing pancreatitis. The severity of pancreatitis-associated lung injury was worsened after TPO treatment, but attenuated after Anti-TPO antibody treatment. In conclusion, serum TPO is up-regulated in the necrotizing pancreatitis induced by l-arginine in mice and may be a risk factor for the pancreatic acinar necrosis in AP. As a pro-necrotic factor, blockade of TPO can attenuate the acinar necrosis in AP and may be a possible therapeutic intervention for AP.     

Pancreatic secretory trypsin inhibitor I reduces the severity of chronic pancreatitis in mice overexpressing interleukin-1β in the pancreas

IL-1β is believed to play a pathogenic role in the development of pancreatitis. Expression of human IL-1β in pancreatic acinar cells produces chronic pancreatitis, characterized by extensive intrapancreatic inflammation, atrophy, and fibrosis. To determine if activation of trypsinogen is important in the pathogenesis of chronic pancreatitis in this model, we crossed IL-1β transgenic [Tg(IL1β)] mice with mice expressing a trypsin inhibitor that is normally produced in rat pancreatic acinar cells [pancreatic secretory trypsin inhibitor (PTSI) I]. We previously demonstrated that transgenic expression of PSTI-I [Tg(Psti1)] increased pancreatic trypsin inhibitor activity by 190%. Tg(IL1β) mice were found to have marked pancreatic inflammation, characterized by histological changes, including acinar cell loss, inflammatory cell infiltration, and fibrosis, as well as elevated myeloperoxidase activity and elevated pancreatic trypsin activity, as early as 6 wk of age. In contrast to Tg(IL1β) mice, pancreatitis was significantly less severe in dual-transgenic [Tg(IL1β)-Tg(Psti1)] mice expressing IL-1β and PSTI-I in pancreatic acinar cells. These findings indicate that overexpression of PSTI-I reduces the severity of pancreatitis and that pancreatic trypsin activity contributes to the pathogenesis of an inflammatory model of chronic pancreatitis.     

Piperine ameliorates the severity of cerulein-induced acute pancreatitis by inhibiting the activation of mitogen activated protein kinases

Piperine is a phenolic component of black pepper (Piper nigrum) and long pepper (Piper longum), fruits used in traditional Asian medicine. Our previous study showed that piperine inhibits lipopolysaccharide-induced inflammatory responses. In this study, we investigated whether piperine reduces the severity of cerulein-induced acute pancreatitis (AP). Administration of piperine reduced histologic damage and myeloperoxidase (MPO) activity in the pancreas and ameliorated many of the examined laboratory parameters, including the pancreatic weight (PW) to body weight (BW) ratio, as well as serum levels of amylase and lipase and trypsin activity. Furthermore, piperine pretreatment reduced the production of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 during cerulein-induced AP. In accordance with in vivo results, piperine reduced cell death, amylase and lipase activity, and cytokine production in isolated cerulein-treated pancreatic acinar cells. In addition, piperine inhibited the activation of mitogen-activated protein kinases (MAPKs). These findings suggest that the anti-inflammatory effect of piperine in cerulein-induced AP is mediated by inhibiting the activation of MAPKs. Thus, piperine may have a protective effect against AP.     

Cinnamic acid nanoparticles modulate redox signal and inflammatory response in gamma irradiated rats suffering from acute pancreatitis

Acute Pancreatitis (AP) is a multifactorial disease. It was characterized by severe inflammation and acinar cell destruction. Thus, the present study was initiated to evaluate the role the of Cinnamic acid nanoparticles (CA-NPs) as a modulator for the redox signaling pathway involved in the development of pancreatitis. AP in rats was induced by L-arginine and exposure to gamma radiation. The pancreatic injury was evaluated using biochemical and histological parameters. Upon the oral administration of CA-NPs, both the severity of acute pancreatitis and the serum levels of amylase and lipase were decreased. Furthermore, the malondialdehyde (MDA) levels of the pancreatic tissue were significantly reduced and the depletion of glutathione was considerably restored. The injury and apoptosis of pancreatic tissues were markedly improved by the reduction of the caspase-3 levels. Additionally, the alleviation of pancreatic oxidative damage by CA-NPs was accompanied by a down-regulation of the NLRP3, NF-κB, and ASK1/MAPK signaling pathways. Collectively, the current findings showed that CA-NPs could protect the pancreatic acinar cell from injury not only by its antioxidant, anti-inflammatory effect but also by modulation of the redox-sensitive signal transduction pathways contributed to acute pancreatitis severity. Accordingly, cinnamic acid nanoparticles have therapeutic potential for the management of acute pancreatitis.     

Complement factor C5a exerts an anti-inflammatory effect in acute pancreatitis and associated lung injury

Complement factor C5a acting via C5a receptors (C5aR) is recognized as an anaphylotoxin and chemoattractant that exerts proinflammatory effects in many pathological states. The effects of C5a and C5aR in acute pancreatitis and in pancreatitis-associated lung injury were evaluated using genetically altered mice that either lack C5aR or do not express C5. Pancreatitis was induced by administration of 12 hourly injections of cerulein (50 microg/kg ip). The severity of pancreatitis was determined by measuring serum amylase, neutrophil sequestration in the pancreas, and acinar cell necrosis. The severity of lung injury was evaluated by measuring neutrophil sequestration in the lung and pulmonary microvascular permeability. In both strains of genetically altered mice, the severity of pancreatitis and pancreatitis-associated lung injury was greater than that noted in the comparison wild-type strains of C5aR- and C5-sufficient animals. This exacerbation of injury in the absence of C5a function indicates that, in pancreatitis, C5a exerts an anti-inflammatory effect. Potentially, C5a and its receptor are capable of both promoting and reducing the extent of acute inflammation.     

TNF-alpha-dependent regulation of acute pancreatitis severity by Ly-6C(hi) monocytes in mice

The roles of monocytes/macrophages and their mechanisms of action in the regulation of pancreatitis are poorly understood. To address these issues, we have employed genetically altered mouse strains that either express the human diphtheria toxin receptor (DTR) coupled to the CD11b promoter or have global deletion of TNF-α. Targeted, conditional depletion of monocytes/macrophages was achieved by administration of diphtheria toxin (DT) to CD11b-DTR mice. We show that in the absence of DT administration, pancreatitis is associated with an increase in pancreatic content of Ly-6C(hi) monocytes/macrophages but that this response is prevented by prior administration of DT to CD11b-DTR mice. DT administration also reduces pancreatic edema and acinar cell injury/necrosis in two dissimilar experimental models of acute pancreatitis (a secretagogue-induced model and a model elicited by retrograde pancreatic duct infusion of sodium taurocholate). In the secretagogue-elicited model, the DT-induced decrease in pancreatitis severity is reversed by adoptive transfer of purified Ly-6C(hi) monocytes harvested from non-DT-treated CD11b-DTR mice or by the transfer of purified Ly-6C(hi) monocytes harvested from TNF-α(+/+) donor mice, but it is not reversed by the transfer of Ly-6C(hi) monocytes harvested from TNF-α(-/-) donors. Our studies indicate that the Ly-6C(hi) monocyte subset regulates the severity of pancreatitis by promoting pancreatic edema and acinar cell injury/necrosis and that this phenomenon is dependent upon the expression of TNF-α by those cells. They suggest that therapies targeting Ly-6C(hi) monocytes and/or TNF-α expression by Ly-6C(hi) monocytes might prove beneficial in the prevention or treatment of acute pancreatitis.     

Pro- and anti-inflammatory response of acinar cells during acute pancreatitis. Effect of N-acetyl cysteine

We investigate the ability of acinar cells to produce tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) at different stages of acute pancreatitis (AP). Since oxidative stress is involved in the inflammatory response, the effect of N-acetyl cysteine (NAC) has also been evaluated. AP was induced in rats by bile-pancreatic duct obstruction (BPDO). NAC (50 mg/kg) was administered 1h before and 1h after BPDO. Acinar cells were incubated for 4 h at 37 degrees C in 5% CO2 atmosphere in absence and presence of 24-h BPDO-PAAF (20%, v/v) as stimulant agent. Acinar production of TNF-alpha and IL-10 was analysed by flow cytometry. Plasma amylase activity and histological studies of the pancreas indicated the severity of AP. PAAF significantly stimulated the acinar production of TNF-alpha and IL-10 in control rats. TNF-alpha production was also significantly stimulated in acinar cells of rats with AP, although a decrease in the pro-inflammatory response was found from 6 h after BPDO onwards. However, acinar cells failed to produce IL-10 from 3 h after BPDO. The protective effect of NAC treatment against oxidative cell damage reduced the pancreatic injury and maintained and enhanced the ability of acinar cells to produce IL-10 at early AP stages. As long as acinar cells were not severely damaged in the course of AP, greater ability to produce cytokines in response to PAAF was found in those with higher forward scatter (R2 cells). We suggest that the capability of acinar cells to maintain an appropriate balance between the production of pro- and anti-inflammatory mediators could contribute to determine the degree of severity of AP.     

Treatment with antileukinate, a CXCR2 chemokine receptor antagonist, protects mice against acute pancreatitis and associated lung injury

Acute pancreatitis is a common, and as yet incurable, clinical condition, the incidence of which has been increasing over recent years. Chemokines are believed to play a key role in the pathogenesis of acute pancreatitis. We have earlier shown that treatment with a neutralizing antibody against CINC, a CXC chemokine, protects rats against acute pancreatitis-associated lung injury. The hexapeptide antileukinate (Ac-RRWWCR-NH2) is a potent inhibitor of binding of CXC chemokines to the receptors (CXCR2). This study aims to evaluate the effect of treatment with antileukinate on acute pancreatitis and the associated lung injury in mice. Acute pancreatitis was induced in adult male Swiss mice by hourly intra-peritoneal injections of caerulein (50 microg/kg/h) for 10 h. Antileukinate (52.63 mg/kg, s.c.) was administered to mice either 30 min before or 1 h after starting caerulein injections. Severity of acute pancreatitis was determined by measuring plasma amylase, pancreatic water content, pancreatic myeloperoxidase (MPO) activity, pancreatic macrophage inflammatory protein-2 (MIP-2) levels and histological examination of sections of pancreas. A rise in lung MPO activity and histological evidence of lung injury in lung sections was used as criteria for pancreatitis-associated lung injury. Treatment with antileukinate protected mice against acute pancreatitis and associated lung injury, showing thereby that anti-chemokine therapy may be of value in this condition.     

Apoptosis versus necrosis in acute pancreatitis

Acute pancreatitis is a disease of variable severity in which some patients experience mild, self-limited attacks, whereas others manifest a severe, highly morbid, and frequently lethal attack. The events that regulate the severity of acute pancreatitis are, for the most part, unknown. It is generally believed that the earliest events in acute pancreatitis occur within acinar cells and result in acinar cell injury. Other processes, such as recruitment of inflammatory cells and generation of inflammatory mediators, are believed to occur subsequent to acinar cell injury, and these "downstream" events are believed to influence the severity of the disease. Several recently reported studies, however, have suggested that the acinar cell response to injury may, itself, be an important determinant of disease severity. In these studies, mild acute pancreatitis was found to be associated with extensive apoptotic acinar cell death, whereas severe acute pancreatitis was found to involve extensive acinar cell necrosis but very little acinar cell apoptosis. These observations led to the hypothesis that apoptosis could be a favorable response to acinar cells and that interventions that favor induction of apoptotic, as opposed to necrotic, acinar cell death might reduce the severity of an attack of acute pancreatitis. Indeed, in an experimental setting, the induction of pancreatic acinar cell apoptosis protects mice against acute pancreatitis. Little is known about the mechanism of apoptosis in the pancreatic acinar cell, although some early attempts have been made in that direction. Also, clinical relevance of these experimental studies remains to be investigated.     

Treatment with bindarit, a blocker of MCP-1 synthesis, protects mice against acute pancreatitis

Chemokines are believed to play a key role in the pathogenesis of acute pancreatitis. We have earlier shown that pancreatic acinar cells produce the chemokine monocyte chemotactic protein (MCP)-1 in response to caerulein hyperstimulation, demonstrating that acinar-derived MCP-1 is an early mediator of inflammation in acute pancreatitis. Blocking chemokine production or action is a major target for pharmacological intervention in a variety of inflammatory diseases, such as acute pancreatitis. 2-Methyl-2-[[1-(phenylmethyl)-1H-indazol-3yl]methoxy]propanoic acid (bindarit) has been shown to preferentially inhibit MCP-1 production in vitro in monocytes and in vivo without affecting the production of the cytokines IL-1, IL-6, or the chemokines IL-8, protein macrophage inflammatory-1alpha, and RANTES. The present study aimed to define the role of MCP-1 in acute pancreatitis with the use of bindarit. In a model of acute pancreatitis induced by caerulein hyperstimulation, prophylactic as well as therapeutic treatment with bindarit significantly reduced MCP-1 levels in the pancreas. Also, this treatment significantly protected mice against acute pancreatitis as evident by attenuated hyperamylasemia neutrophil sequestration in the pancreas (pancreatic MPO activity), and pancreatic acinar cell injury/necrosis on histological examination of pancreas sections.     

Exenatide does not evoke pancreatitis and attenuates chemically induced pancreatitis in normal and diabetic rodents

The risk of developing pancreatitis is elevated in type 2 diabetes and obesity. Cases of pancreatitis have been reported in type 2 diabetes patients treated with GLP-1 (GLP-1R) receptor agonists. To examine whether the GLP-1R agonist exenatide potentially induces or modulates pancreatitis, the effect of exenatide was evaluated in normal or diabetic rodents. Normal and diabetic rats received a single exenatide dose (0.072, 0.24, and 0.72 nmol/kg) or vehicle. Diabetic ob/ob or HF-STZ mice were infused with exenatide (1.2 and 7.2 nmol·kg(-1)·day(-1)) or vehicle for 4 wk. Post-exenatide treatment, pancreatitis was induced with caerulein (CRN) or sodium taurocholate (ST), and changes in plasma amylase and lipase were measured. In ob/ob mice, plasma cytokines (IL-1β, IL-2, IL-6, MCP-1, IFNγ, and TNFα) and pancreatitis-associated genes were assessed. Pancreata were weighed and examined histologically. Exenatide treatment alone did not modify plasma amylase or lipase in any models tested. Exenatide attenuated CRN-induced release of amylase and lipase in normal rats and ob/ob mice but did not modify the response to ST infusion. Plasma cytokines and pancreatic weight were unaffected by exenatide. Exenatide upregulated Reg3b but not Il6, Ccl2, Nfkb1, or Vamp8 expression. Histological analysis revealed that the highest doses of exenatide decreased CRN- or ST-induced acute inflammation, vacuolation, and acinar single cell necrosis in mice and rats, respectively. Ductal cell proliferation rates were low and similar across all groups of ob/ob mice. In conclusion, exenatide did not modify plasma amylase and lipase concentrations in rodents without pancreatitis and improved chemically induced pancreatitis in normal and diabetic rodents.     

白细胞介素-6在急性胰腺炎中的作用及其机制研究

目的:明确白细胞介素-6(IL-6)在小鼠急性胰腺炎中的作用及其机制研究。方法:通过胰胆管结扎的方法诱导小鼠急性胰腺炎;分离小鼠胰腺腺泡细胞。采用ELISA方法检测胰腺组织或腺泡细胞裂解物中的细胞因子;通过western blot分析检测组织或细胞中IL-6或ERK表达。结果:IL-6浓度在胰腺组织和腺泡细胞中显著增加(P0.05)。在离体原代小鼠腺泡细胞,TNF-α刺激增加IL-6释放(P0.05);与此同时,IL-6刺激可增加其它促炎性细胞因子的释放,两者都涉及ERK MAP激酶通路。黄酮类化合物木犀草素抑制IL-6刺激引起白细胞介素-6(IL-6)和人巨嗜细胞激活蛋白-1(CCL2/MCP-1)释放。最后进一步证实,IL-6激活人胰腺组织中的ERK。结论:IL-6在急性胰腺炎中增加,激活炎症通路并加重急性胰腺炎。     

Necro-inflammatory response of pancreatic acinar cells in the pathogenesis of acute alcoholic pancreatitis

The role of pancreatic acinar cells in initiating necro-inflammatory responses during the early onset of alcoholic acute pancreatitis (AP) has not been fully evaluated. We investigated the ability of acinar cells to generate pro- and anti-inflammatory mediators, including inflammasome-associated IL-18/caspase-1, and evaluated acinar cell necrosis in an animal model of AP and human samples. Rats were fed either an ethanol-containing or control diet for 14 weeks and killed 3 or 24 h after a single lipopolysaccharide (LPS) injection. Inflammasome components and necro-inflammation were evaluated in acinar cells by immunofluorescence (IF), histology, and biochemical approaches. Alcohol exposure enhanced acinar cell-specific production of TNFα, IL-6, MCP-1 and IL-10, as early as 3 h after LPS, whereas IL-18 and caspase-1 were evident 24 h later. Alcohol enhanced LPS-induced TNFα expression, whereas blockade of LPS signaling diminished TNFα production in vitro, indicating that the response of pancreatic acinar cells to LPS is similar to that of immune cells. Similar results were observed from acinar cells in samples from patients with acute/recurrent pancreatitis. Although morphologic examination of sub-clinical AP showed no visible signs of necrosis, early loss of pancreatic HMGB1 and increased systemic levels of HMGB1 and LDH were observed, indicating that this strong systemic inflammatory response is associated with little pancreatic necrosis. These results suggest that TLR-4-positive acinar cells respond to LPS by activating the inflammasome and producing pro- and anti-inflammatory mediators during the development of mild, sub-clinical AP, and that these effects are exacerbated by alcohol injury.     

The Novel Cytokine Interleukin-33 Activates Acinar Cell Proinflammatory Pathways and Induces Acute Pancreatic Inflammation in Mice

Background

Acute pancreatitis is potentially fatal but treatment options are limited as disease pathogenesis is poorly understood. IL-33, a novel IL-1 cytokine family member, plays a role in various inflammatory conditions but its role in acute pancreatitis is not well understood. Specifically, whether pancreatic acinar cells produce IL-33 when stressed or respond to IL-33 stimulation, and whether IL-33 exacerbates acute pancreatic inflammation is unknown.

Methods/Results

In duct ligation-induced acute pancreatitis in mice and rats, we found that (a) IL-33 concentration was increased in the pancreas; (b) mast cells, which secrete and also respond to IL-33, showed degranulation in the pancreas and lung; (c) plasma histamine and pancreatic substance P concentrations were increased; and (d) pancreatic and pulmonary proinflammatory cytokine concentrations were increased. In isolated mouse pancreatic acinar cells, TNF-α stimulation increased IL-33 release while IL-33 stimulation increased proinflammatory cytokine release, both involving the ERK MAP kinase pathway; the flavonoid luteolin inhibited IL-33-stimulated IL-6 and CCL2/MCP-1 release. In mice without duct ligation, exogenous IL-33 administration induced pancreatic inflammation without mast cell degranulation or jejunal inflammation; pancreatic changes included multifocal edema and perivascular infiltration by neutrophils and some macrophages. ERK MAP kinase (but not p38 or JNK) and NF-kB subunit p65 were activated in the pancreas of mice receiving exogenous IL-33, and acinar cells isolated from the pancreas of these mice showed increased spontaneous cytokine release (IL-6, CXCL2/MIP-2α). Also, IL-33 activated ERK in human pancreatic tissue.

Significance

As exogenous IL-33 does not induce jejunal inflammation in the same mice in which it induces pancreatic inflammation, we have discovered a potential role for an IL-33/acinar cell axis in the recruitment of neutrophils and macrophages and the exacerbation of acute pancreatic inflammation.

Conclusion

IL-33 is induced in acute pancreatitis, activates acinar cell proinflammatory pathways and exacerbates acute pancreatic inflammation.     

Activity of Ligustrum vulgare L extracts against acute pancreatitis in murine models by regulation of p38 MAPK and NF-κB signaling pathways

Pancreatitis is a fatal disease associated with significant mortality and morbidity. At present, no specific treatment is available for pancreatitis and the patients are mainly treated with supportive medication. The need for specific antipancreatitic chemotherapy is an urgent medical obligation. In the current study, protective effects of the methanolic extract of the Ligustrum vulgare berries were investigated in the rat model of acute pancreatitis. Acute pancreatitis (AP) was induced in the male Sprague-Dawley (SD) rats by cerulein injection. Fruit extract of L. vulgare L extract was prepared using the methanol. Treatment effects of L. vulgare were evaluated in AP rats. Serum levels of lipase, amylase, proinflamatory cytokines (TNF-α, IL-6, TL-1β), lipid peroxidase (LPO), myeloperoxidase (MPO) were determined. Histological changes in the pancreas were assessed. L. vulgare treatment prevented the increase in serum amylase and lipase levels, reduced the disease progression in pancreas, and reduced the serum levels of tumour necrosis factor (TNF)-α, interleukin (IL)-6, and IL-1β in AP rats. Moreover, L. vulgare significantly suppressed pancreatic edema, inhibited oxidative damage (MPO activity and SOD activity), and inhibited the expression of NF-κB/p65 and activation (phosphorylation) of the inhibitor of NF-κB (IκBα) and p38 MAPKs. Histological examinations showed that L. vulgare significantly reduced the inflammatory and fibrotic changes. The results indicated the potent pancreato-protective effects of L. vulgare in AP.     

血红素加氧酶-1对急性重症胰腺炎相关肺损伤TLR4/NF-κB通路的影响

目的:探讨血红素加氧酶-1(HO-1)对急性重症胰腺炎相关肺损伤(PALI)Toll样受体-4(TLR4)/核因子-κB(NF-κB)信号传导通路的影响。方法:32只SD大鼠随机分为Sham组、PALI组、HO-1促进剂组、HO-1抑制剂组,每组8只。PALI组经胆胰管注入牛磺胆酸钠制备急性重症胰腺炎(ANP)动物模型。Sham组胆胰管内不注入牛磺胆酸钠,其余操作同PALI组。HO-1促进剂组于造模后30 min经腹腔注射牛血晶素75μg/kg;HO-1抑制剂组于造模后30 min经腹腔注射锌-原卟啉20μmol/kg。PALI组和Sham组均于造模后30 min经腹腔注射等量生理盐水。各组大鼠术后24 h,进行肺损伤学评分,统计肺湿/干重比值。检测大鼠术后24 h血清淀粉酶、TNF-α、IL-6、NGAL水平。检测大鼠术后24 h肺组织中TLR4、NF-κB p65蛋白表达。结果:PALI组肺损伤学评分、肺湿/干重比值、淀粉酶、TNF-α、IL-6、NGAL、TLR4、NF-κB p65明显高于Sham组;HO-1促进剂组肺损伤学评分、肺湿/干重比值、淀粉酶、TNF-α、IL-6、NGAL、TLR4、NF-κB p65明显低于PALI组;HO-1抑制剂组肺损伤学评分、肺湿/干重比值、淀粉酶、TNF-α、IL-6、NGAL、TLR4、NF-κBp65明显高于PALI组;差异均有统计学意义(P<0.05)。结论:HO-1能够通过抑制TLR4/NF-κB信号通路的激活,下调TNF-α、IL-6、NGAL等炎症因子的释放,从而发挥减轻急性重症胰腺炎相关肺损伤的作用。