Atrial natriuretic peptide reduces inflammation and enhances apoptosis in rat acute pancreatitis

Berberine Attenuates Cerulein-Induced Acute Pancreatitis by Modulating Nrf2/NOX2 Signaling Pathway via AMPK Activation

AMP-activated protein kinase (AMPK) is the master regulator of cellular energy which gets activated during energy stress and restores tissue homeostasis. AMPK is widely expressed in the pancreas and is involved in protein synthesis. In cerulein-induced acute pancreatitis (AP), diminished AMPK activity in the pancreatic tissue may be associated with pancreatic inflammation and oxidative stress. Our results demonstrated that berberine (BR) treatment produced significant decrease in plasma amylase and lipase levels and improved histopathological features in AP mice model. Myeloperoxidase (MPO) activity indicated that BR suppressed the infiltration of neutrophils in pancreas. BR treatment markedly decreased the levels of proinflammatory cytokines including interleukins (IL)-6, IL-1β, and tumor necrosis factor-α (TNF-α) via inhibition of nicotinamide adenine dinucleotide phosphate oxidase 2 (NOX2) expression. In addition, BR activates the nuclear factor erythroid 2-related factor 2 (Nrf2) signaling and inhibits cerulein-induced oxidative-nitrosative stress. Mechanistically, we found inhibition of AMPK activity in cerulein-induced AP, while BR-treated animals showed marked increase in the AMPK expression. Together, our study indicated that BR-mediated AMPK activation in pancreatic tissues demonstrated attenuation of cerulein-induced oxidative stress and inflammation. Based on our observations, further exploration of this promising natural product against AP and associated complications may lead to promising therapeutic options.

Endoplasmic reticulum stress in acute pancreatitis: Exploring the molecular mechanisms and therapeutic targets

Acute pancreatitis (AP) is associated with multiple cellular mechanisms that trigger and or are triggered by the inflammatory injury and death of the acinar cells. One of the key mechanisms is the endoplasmic reticulum (ER) stress, which manifests as an accumulation of misfolded proteins within ER, an event that has proinflammatory and proapoptotic consequences. Hence, the degree of cell insult during AP could considerably depend on the signaling pathways that are upregulated during ER stress and its resulting dyshomeostasis such as C/EBP homologous protein (CHOP), cJUN NH2-terminal kinase (JNK), nuclear factor kappa B (NF-κB), and NOD-like receptor protein 3 (NLRP3) inflammasome. Exploring these molecular pathways is an interesting area for translational medicine as it may lead to identifying new therapeutic targets in AP. This review of the literature aims to shed light on the different roles of ER stress in the etiopathogenesis and pathogenesis of AP. Then, it specifically focuses on the therapeutic implications of ER stress in this context.

Targeting myocardial inflammation: investigating the therapeutic potential of atrial natriuretic peptide in atrial fibrosis

BACKGROUND

Atrial Fibrillation (AF), a prevalent arrhythmic condition, is intricately associated with atrial fibrosis, a major pathological contributor. Central to the development of atrial fibrosis is myocardial inflammation. This study focuses on Atrial Natriuretic Peptide (ANP) and its role in mitigating atrial fibrosis, aiming to elucidate the specific mechanisms by which ANP exerts its effects, with an emphasis on fibroblast dynamics.

METHODS AND RESULTS

The study involved forty Sprague-Dawley rats, divided into four groups: control, Angiotensin II (Ang II), Ang II + ANP, and ANP only. The administration of 1 µg/kg/min Ang II was given to Ang II and Ang II + ANP groups, while both Ang II + ANP and ANP groups received 0.1 µg/kg/min ANP intravenously for a duration of 14 days. Cardiac fibroblasts were used for in vitro validation of the proposed mechanisms. The study observed that rats in the Ang II and Ang II + ANP groups showed an increase in blood pressure and a decrease in body weight, more pronounced in the Ang II group. Diastolic dysfunction, a characteristic of the Ang II group, was alleviated by ANP. Additionally, ANP significantly reduced Ang II-induced atrial fibrosis, myofibroblast proliferation, collagen overexpression, macrophage infiltration, and the elevated expression of Interleukin 6 (IL-6) and Tenascin-C (TN-C). Transcriptomic sequencing indicated enhanced PI3K/Akt signaling in the Ang II group. Furthermore, in vitro studies showed that ANP, along with the PI3K inhibitor LY294002, effectively reduced PI3K/Akt pathway activation and the expression of TN-C, collagen-I, and collagen-III, which were induced by Ang II.

CONCLUSIONS

The study demonstrates ANP's potential in inhibiting myocardial inflammation and reducing atrial fibrosis. Notably, ANP's effect in countering atrial fibrosis seems to be mediated through the suppression of the Ang II-induced PI3K/Akt-Tenascin-C signaling pathway. These insights enhance our understanding of AF pathogenesis and position ANP as a potential therapeutic agent for treating atrial fibrosis.

New insights into regulatory cell death and acute pancreatitis

Acute pancreatitis (AP) may be associated with both local and systemic complications. Although it is usually self-limiting, up to 20% of patients develop severe acute pancreatitis (SAP), which leads to systemic inflammatory response syndrome (SIRS) and multiorgan dysfunction and failure affecting the lung, kidney, liver and heart. Patients who survive the condition frequently develop devastating long-term consequences such as diabetes mellitus, exocrine pancreatic insufficiency, chronic pancreatitis (CP) and poor quality of life. A lack of specific targeted treatments is the main reason for high mortality and morbidity, indicating that more research on the pathogenesis of AP is needed. In the past decade, substantial advancements have been made in our understanding of the pathophysiological mechanisms of AP, including mechanisms of calcium-mediated acinar cell injury and death, the cytoprotective role of the unfolded protein response (UPR) and autophagy in preventing sustained endoplasmic reticulum stress (ERs); however, the mechanism of parenchymal cell death is relatively poorly understood. This paper reviews the research progress of the regulatory cell death (RCD) mode in the pathogenesis of AP, providing some new insights and regulatory targets for the pathogenesis and treatment of AP, facilitating better targeted drug development.

Ameliorating effect of rutin against diclofenac-induced cardiac injury in rats with underlying function of FABP3, MYL3, and ANP

Diclofenac is a widely prescribed anti-inflammatory drug having cardiovascular complications as one of the main liabilities that restrict its therapeutic use. We aimed to investigate for any role of rutin against diclofenac-induced cardiac injury with underlying mechanisms as there is no such precedent to date. The effect of rutin (10 and 20 mg/kg) was evaluated upon concomitant oral administration for fifteen days with diclofenac (10 mg/kg). Rutin significantly attenuated diclofenac-induced alterations in the serum cardiac markers (LDH, CK-MB, and SGOT), serum cytokine levels (TNF-α and IL-6), and oxidative stress markers (MDA and GSH) in the cardiac tissue. Histopathological examination and Scanning Electron Microscopy (SEM) findings displayed a marked effect of rutin to prevent diclofenac-mediated cardiac injury. Altered protein expression of myocardial injury markers (cTnT, FABP3, and ANP) and apoptotic markers (Bcl-2 and Caspase-3) in the cardiac tissue upon diclofenac treatment was considerably shielded by rutin treatment. MYL3 was unaffected due to diclofenac or rutin treatment. Rutin also significantly improved diclofenac-induced gastrointestinal and hepatic alterations based on the observed ameliorative effects in key mediators, oxidative stress markers, histopathology examination, and SEM findings. Overall results suggest that rutin can protect the diclofenac-induced cardiac injury by lowering oxidative stress, inhibiting inflammation, and reducing apoptosis. Further research work directs toward the development of phytotherapeutics for cardioprotection.

Natriuretic peptide receptor-C mediates the inhibitory effect of atrial natriuretic peptide on neutrophil recruitment to the lung during acute lung injury

Atrial natriuretic peptide (ANP) protects against acute lung injury (ALI), but the receptor that mediates this effect is not known. Transgenic mice with 0 (knockout), 1 (heterozygote), or 2 (wild-type) functional copies of Npr3, the gene that encodes for natriuretic peptide receptor-C (NPR-C), were treated with intravenous infusion of ANP or saline vehicle before oropharyngeal aspiration of Pseudomonas aeruginosa (PA103) or saline vehicle. Lung injury was assessed 4 h following aspiration by measurement of lung wet/dry (W/D) weight, whole lung leukocyte and cytokine levels, and protein, leukocyte, and cytokine concentration in bronchoalveolar lavage fluid (BALF). PA103 induced acute lung injury as evidenced by increases in lung W/D ratio and protein concentration in BALF. The severity of PA103-induced lung injury did not differ between NPR-C genotypes. Treatment with intravenous ANP infusion reduced PA103-induced increases in lung W/D and BALF protein concentration in all three NPRC genotypes. PA103 increased the percentage of leukocytes that were neutrophils and cytokine levels in whole lung and BALF in NPR-C wild-type and knockout mice. This effect was blunted by ANP in wild-type mice but not in the NPR-C knockout mice. NPR-C does not mediate the protective effect of ANP on endothelial cell permeability in settings of PA103-induced injury but may mediate the effect of ANP on inhibition of the recruitment of neutrophils to the lung and thereby attenuate the release of inflammatory cytokines.

Pleiotropic Roles of Atrial Natriuretic Peptide in Anti-Inflammation and Anti-Cancer Activity

Simple Summary

The relationship between inflammation and carcinogenesis, as well as the response to anti-tumor therapy, is intimate. Atrial natriuretic peptides (ANPs) play a pivotal role in the homeostatic control of blood pressure, electrolytes, and water balance. In addition, ANPs exert immune-modulatory effects in the tissue microenvironment, thus exhibiting a fascinating ability to prevent inflammation-related tumorigenesis and cancer recurrence. In cancers, ANPs show anti-proliferative effects through several molecular pathways. Furthermore, ANPs attenuate the side effects of cancer therapy. Therefore, ANPs have potential therapeutic value in tumors. Here, we summarized the roles of ANPs in diverse aspects of the immune system and the molecular mechanisms underlying the anti-cancer effects of ANPs, contributing to the development of ANP-based anti-cancer agents.

Abstract

The atrial natriuretic peptide (ANP), a cardiovascular hormone, plays a pivotal role in the homeostatic control of blood pressure, electrolytes, and water balance and is approved to treat congestive heart failure. In addition, there is a growing realization that ANPs might be related to immune response and tumor growth. The anti-inflammatory and immune-modulatory effects of ANPs in the tissue microenvironment are mediated through autocrine or paracrine mechanisms, which further suppress tumorigenesis. In cancers, ANPs show anti-proliferative effects through several molecular pathways. Furthermore, ANPs attenuate the side effects of cancer therapy. Therefore, ANPs act on several hallmarks of cancer, such as inflammation, angiogenesis, sustained tumor growth, and metastasis. In this review, we summarized the contributions of ANPs in diverse aspects of the immune system and the molecular mechanisms underlying the anti-cancer effects of ANPs.

Enhancing or inhibiting apoptosis? The effects of ucMSC-Ex in the treatment of different degrees of traumatic pancreatitis

The animal models of traumatic pancreatitis (TP) were established to evaluate the specific mechanisms by which umbilical cord mesenchymal stem cell-derived exosomes (ucMSC-Ex) exert therapeutic effects. Sixty four rats were randomly divided into eight groups, including TP groups with three different degrees and relevant groups with ucMSC-Ex treated. The degrees of pancreatic tissue injury were evaluated by Histological Examination. Furthermore, enzyme-linked immunosorbent assay were applied to evaluate the activity of pancreatic enzymes and levels of inflammatory factors in serum. Finally, the apoptotic effects of each group were evaluated by TUNEL, western blot (WB), and real time fluorescence quantitative polymerase chain reaction (RT-qPCR). The pancreatic histopathological score and serum amylase and lipase levels gradually increased in various degrees of TP and the levels in the treatment group were all significantly decreased. The apoptosis index gradually increased in each TP group and significantly decreased in the treatment group in TUNEL results. WB and RT-qPCR showed the same trend, that bax and caspase-3 gradually increased and bcl-2 gradually decreased in TP groups. Compared with TP groups, the expression of bax and caspase-3 were lower while bcl-2 expression was higher in the treatment group. ucMSC-Ex suppressed the inflammatory response and inhibited pancreatic acinar cell apoptosis to promote repair of injured pancreatic tissue.

Function and regulation of corin in physiology and disease

Atrial natriuretic peptide (ANP) is of major importance in the maintenance of electrolyte balance and normal blood pressure. Reduced plasma ANP levels are associated with the increased risk of cardiovascular disease. Corin is a type II transmembrane serine protease that converts the ANP precursor to mature ANP. Corin deficiency prevents ANP generation and alters electrolyte and body fluid homeostasis. Corin is synthesized as a zymogen that is proteolytically activated on the cell surface. Factors that disrupt corin folding, intracellular trafficking, cell surface expression, and zymogen activation are expected to impair corin function. To date, CORIN variants that reduce corin activity have been identified in hypertensive patients. In addition to the heart, corin expression has been detected in non-cardiac tissues, where corin and ANP participate in diverse physiological processes. In this review, we summarize the current knowledge in corin biosynthesis and post-translational modifications. We also discuss tissue-specific corin expression and function in physiology and disease.

Therapeutic role of atrial natriuretic peptide in early treatment of traumatic hemorrhagic shock

The biological effect of atrial natriuretic peptide (ANP) in traumatic hemorrhagic shock (THS) is unknown. This study was to evaluate whether ANP therapy can show organ protection in THS. Thirty male Sprague-Dawley rats were divided into three groups: ANP group, sham group, and control group. Pressure-controlled THS was induced in rats in ANP group and control group. ANP at a rate of 0.025 μg/kg/min was infused in ANP group during near-80 min of shock. After that, animals were resuscitated for 60 min and observed until 24 h. Hemodynamic parameters during shock and resuscitation were measured. Serum levels of ANP and lactate dehydrogenase, tissue oxidative stress and inflammatory factors, as well as liver and kidney function were determined. Tissue apoptosis was also assessed. There was no statistically significant difference between ANP group and control group in arterial pressure throughout the 150 min monitoring period. Blood urea nitrogen at 90 min and 24 h in ANP group was significantly lower than control group. Alanine transaminase and aspartate aminotransferase activity at 90 min in control group were significantly higher than that in sham group. However, hepatic enzyme activity at 90 min in ANP group was not significantly different compared with sham or control group. After 24 h, myocardial expression of caspase 3 protein in ANP group was significantly reduced compared with control group. Jejunal and hepatic Malondialdehyde was increased following ANP treatment. ANP therapy during early THS has no significant adverse effect on hemodynamics but can exert oxidative stress and certain protective effect on multiple organs. Our study may shed light on the novel therapy of THS with regard to organ protection. The mechanisms underlying the organ protection require further study.

Nimbolide ameliorates pancreatic inflammation and apoptosis by modulating NF-κB/SIRT1 and apoptosis signaling in acute pancreatitis model

Acute pancreatitis (AP) is a potential gastrointestinal problem most commonly associated with pancreatic inflammation and acinar cells injury. Nimbolide (NB), isolated from the tree Azadirachta indica, possesses antioxidant and anti-inflammatory effects. Here, we aimed to investigate the pancreatic protective effects of NB in ameliorating cerulein-induced pancreatic inflammation and apoptosis in AP model and evaluate the potential mechanism of action. AP was induced in Swiss albino mice by six-hourly intraperitoneal exposures of cerulein (50 µg/kg/hr) and pre-treatment of NB (0.3 and 1 mg/kg) 7 days prior to the cerulein exposure. Various parameters associated with AP in plasma and pancreatic tissues were evaluated. Severity of AP was effectively ameliorated by NB as shown by reducing pancreatic edema, plasma amylase and lipase levels, MPO levels and in cerulein-induced histological damage. Further, the antioxidant effect of NB was associated with a significant inhibition of oxidative-nitrosative stress in Raw 264.7 cells and cerulein-induced AP mice. Moreover, NB suppressed proinflammatory cytokines, iNOS and nitrotyrosine expression. In addition, NB inhibited NF-κB activation and increased SIRT1 expression in cerulein challenged mice. Furthermore, NB also inhibited pancreatic apoptosis by downregulating cleaved caspase 3 and Bax while upregulating Bcl2 expression in cerulein-treated mice. Inhibition of pancreatic inflammation and apoptosis resulted in attenuation of cerulein-induced AP. These results suggest that NB exerts strong anti-pancreatitis effects against cerulein-induced AP by combating inflammatory and apoptosis signaling via SIRT1 activation.

Differential effects of low-dose sacubitril and/or valsartan on renal disease in salt-sensitive hypertension

Diuretics and renin-angiotensin system blockers are often insufficient to control the blood pressure (BP) in salt-sensitive (SS) subjects. Abundant data support the proposal that the level of atrial natriuretic peptide may correlate with the pathogenesis of SS hypertension. We hypothesized here that increasing atrial natriuretic peptide levels with sacubitril, combined with renin-angiotensin system blockage by valsartan, can be beneficial for alleviation of renal damage in a model of SS hypertension, the Dahl SS rat. To induce a BP increase, rats were challenged with a high-salt 4% NaCl diet for 21 days, and chronic administration of vehicle or low-dose sacubitril and/or valsartan (75 μg/day each) was performed. Urine flow, Na+ excretion, and water consumption were increased on the high-salt diet compared with the starting point (0.4% NaCl) in all groups but remained similar among the groups at the end of the protocol. Upon salt challenge, we observed a mild decrease in systolic BP and urinary neutrophil gelatinase-associated lipocalin levels (indicative of alleviated tubular damage) in the valsartan-treated groups. Sacubitril, as well as sacubitril/valsartan, attenuated the glomerular filtration rate decline induced by salt. Alleviation of protein cast formation and lower renal medullary fibrosis were observed in the sacubitril/valsartan- and valsartan-treated groups, but not when sacubitril alone was administered. Interestingly, proteinuria was mildly mitigated only in rats that received sacubitril/valsartan. Further studies of the effects of sacubitril/valsartan in the setting of SS hypertension, perhaps involving a higher dose of the drug, are warranted to determine if it can interfere with the progression of the disease.

CircRNA Expression Profiles and the Potential Role of CircZFP644 in Mice With Severe Acute Pancreatitis via Sponging miR-21-3p

Severe acute pancreatitis (SAP) is the most serious type of pancreatitis with high morbidity and mortality. The underlying mechanism behind SAP pathogenesis is complex and remains elusive. Circular RNAs (circRNAs) are emerging as vital regulators of gene expression in various diseases by sponging microRNAs (miRNAs). However, the roles of circRNAs in the pathophysiology of SAP remain unknown. In the present study, next-generation RNA sequencing was utilized to identify circRNA transcripts in the pancreatic tissues from three SAP mice and three matched normal tissues. The differentially expressed circRNAs were confirmed by real-time PCR, and the biological functions of their interaction with miRNAs and mRNAs were analyzed. Our results demonstrate that 56 circRNAs were differentially expressed in SAP mice compared with normal controls. Six differentially expressed circRNAs were confirmed with the sequencing data. Importantly, we characterized a significantly downregulated circRNA derived from the ZFP664 gene in SAP. CircZFP644 was found to be negatively correlated with miR-21-3p, with a perfectly matched binding sequence to miR-21-3p. In conclusion, CircZFP644 may play an important role in the pathogenesis of SAP through sponging miR-21-3p. Our findings may provide novel insights regarding the workings of the pathophysiological mechanism of SAP and offer novel targets for SAP.

Maresin-1 Inhibits Oxidative Stress and Inflammation and Promotes Apoptosis in a Mouse Model of Caerulein-Induced Acute Pancreatitis

Background

This study aimed to investigate the effects of maresin-1 (MaR1) in a mouse model of caerulein-induced acute pancreatitis (AP).

Material/Methods

Fifty C57BL/6 mice with caerulein-induced AP were divided into the untreated control group (N=10), the untreated AP model group (N=10), the MaR1-treated (low-dose, 0.1 μg) AP model group (N=10), the MaR1-treated (middle-dose, 0.5 μg) AP model group (N=10), and the MaR1-treated (high-dose, 1 μg) AP model group (N=10). Enzyme-linked immunoassay (ELISA) measured serum levels of amylase, lipase, tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and IL-6 and mRNA was measured by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Malondialdehyde (MDA), protein carbonyls, superoxide dismutase (SOD), and the ratio of reduced glutathione/oxidized glutathione (GSH/GSSG) were measured. Histology of the pancreas included measurement of acinar cell apoptosis using the terminal-deoxynucleotidyl transferase-mediated nick end-labeling (TUNEL) assay. Western blot measured Toll-like receptor 4 (TLR4), MyD88, and phospho-NF-κB p65, and apoptosis-associated proteins Bcl-2, Bax, cleaved caspase-3, and cleaved caspase-9.

Results

Following treatment with MaR1, serum levels of amylase, lipase, TNF-α, IL-1β, and IL-6 decreased, MDA and protein carbonyl levels decreased, SOD and the GSH/GSSG ratio increased in a dose-dependent manner. In the MaR1-treated AP mice, inflammation of the pancreas and the expression of inflammatory cytokines, pancreatic acinar cell apoptosis, Bcl-2 expression, and expression of TLR4, MyD88, and p-NF-κB p65 were reduced, but Bax, cleaved caspase-3, and cleaved caspase-9 expression increased.

Conclusions

In a mouse model of caerulein-induced AP, treatment with MaR1 reduced oxidative stress and inflammation and reduced apoptosis.

The exocrine pancreas is an extracardiac source of atrial natriuretic peptide

Previous studies have shown that atrial natriuretic peptide (ANP) regulates exocrine pancreatic function in health and disease. As extracardiac sources of ANP have been identified and ANP-like immunoreactivity has been reported in the exocrine pancreas, in the present work we sought to establish whether ANP was produced in the rat exocrine pancreas and if conditions like fasting/feeding or acute pancreatitis were reflected on ANP expression. By using RT-PCR, immunoblotting, and immunofluorescence microscopy assays, it was found that both mRNA and protein ANP were present in the acinar cells of the exocrine pancreas. The amount of ANP in the pancreas was lower in than the atrium but similar to other tissues like the kidney and liver. Immunogold labeling electron microscopy studies revealed that ANP was localized in zymogen granules and the endoplasmic reticulum suggesting local synthesis and package into granules. ANP protein expression was significantly increased not only in fasting but also in acute pancreatitis, the latter probably related to impaired secretion. Natriuretic peptide receptor type C which mediates ANP biological effects in the exocrine pancreas was also present in acinar cells and its expression did not change with either fasting or acute pancreatitis. Present findings show that the exocrine pancreas is a relatively important extracardiac source of ANP and further support previous studies strongly suggesting the active role of the peptide in pancreatic physiology and pathophysiology.

Atrial natriuretic peptide attenuates endoplasmic reticulum stress in experimental acute pancreatitis

Increasing evidence shows that the endoplasmic reticulum (ER) stress is an early event that injures pancreatic acinar cells and contributes to the pathogenesis of acute pancreatitis. In the present work we sought to establish whether atrial natriuretic peptide (ANP) alleviated ER stress in rats with cerulein-induced pancreatitis. The major components of the unfolded protein response (UPR) and their downstream effectors were assessed by immunoblotting or fluorimetry and the ultrastructure of ER evaluated by electron transmission microscopy. Cross-talk with autophagy was evaluated by beclin-1 expression. ANP reduced binding immunoglobulin protein (Bip) expression (UPR major controller) which under non-stress conditions keeps inactive the stress sensor proteins: protein kinase-like ER kinase (PERK), inositol-requiring enzyme-1 (IRE1) and activating transcription factor 6 (ATF6). Although ANP did not change PERK expression it decreased p-eIF2α and enhanced downstream effector CHOP, suggesting that ANP stimulates ER-dependent apoptosis. In accordance, ANP also decreased Bcl2 expression and enhanced proapoptotic proteins Bax and Bak. The atrial peptide enhanced ATF6 expression and although it did not affect IRE1/sXBP1 signaling, it increased caspase-2 activity, also involved in ER-dependent apoptosis. Furthermore, ANP decreased beclin-1 expression. The ultrastructure of the RE revealed decreased swelling and conserved ribosomes in the presence of ANP. Present findings support that ANP alleviates ER stress in acute pancreatitis by modulating the three branches of the UPR and stimulates ER-dependent apoptosis. Gaining insights into the modulation of ER stress may help to develop specific therapeutic strategies for acute pancreatitis and/or medical interventions at risk of its developing like endoscopic retrograde cholangiopancreatography.

Double-stranded RNA-dependent kinase PKR activates NF-κB pathway in acute pancreatitis

The activation of transcription factor nuclear factor kappa B (NF-κB) occurs early in acute pancreatitis (AP) simultaneously with intracellular trypsinogen activation. Double-stranded RNA-dependent kinase (PKR) promotes the activation of NF-κB and the production of pro-inflammatory factors including tumor necrosis factor alpha (TNF-α) and interleukin 6 (IL-6). The rat and rat pancreatic AR42J cells were treated by cerulein to establish AP models, showing PKR increased. TNF-α, IL-6 and lactate dehydrogenase (LDH) in AP pancreatic tissues and cerulein-treated AR42J cells increased, while PKR knockdown in AR42J cells reversed cerulein-induced inflammatory response and pancreatic cell injury. In addition, inhibitor of kappa B kinase α (IKKα), phosphorylated P65 (p-P65), P65 increased in cerulein-treated AR42J cells. Meanwhile, in cerulein-treated AR42J cells, interaction between PKR and IKKα, as well as the co-localization and nuclear accumulation of PKR and P65, were detected. Furthermore, cerulein induced the phosphorylation and nuclear translocation of P65, which indicated the activation of NF-κB, while PKR knockdown hindered NF-κB activation to alleviate pancreatic cell injury. In summary, PKR might promote NF-κB activation via facilitating its phosphorylation and nuclear translocation, thus accelerated inflammatory response and pancreatic cell injury in AP, implying a novel molecular target for the treatment of AP.