Comparative transcriptomic analysis reveals the molecular changes of acute pancreatitis in experimental models

BACKGROUND Acute pancreatitis(AP)encompasses a spectrum of pancreatic inflammatory conditions,ranging from mild inflammation to severe pancreatic necrosis and multisystem organ failure.Given the challenges associated with obtaining human pancreatic samples,research on AP predominantly relies on animal models.In this study,we aimed to elucidate the fundamental molecular mechanisms underlying AP using various AP models.AIM To investigate the shared molecular changes underlying the development of AP across varying severity levels.METHODS AP was induced in animal models through treatment with caerulein alone or in combination with lipopolysaccharide(LPS).Additionally,using Ptf1αto drive the specific expression of the hM3 promoter in pancreatic acinar cells transgenic C57BL/6J-hM3/Ptf1α(cre)mice were administered Clozapine N-oxide to induce AP.Subsequently,we conducted RNA sequencing of pancreatic tissues and validated the expression of significantly different genes using the Gene Expression Omnibus(GEO)database.RESULTS Caerulein-induced AP showed severe inflammation and edema,which were exacerbated when combined with LPS and accompanied by partial pancreatic tissue necrosis.Compared with the control group,RNA sequencing analysis revealed 880 significantly differentially expressed genes in the caerulein model and 885 in the caerulein combined with the LPS model.Kyoto Encyclopedia of Genes and Genomes enrichment analysis and Gene Set Enrichment Analysis indicated substantial enrichment of the TLR and NOD-like receptor signaling pathway,TLR signaling pathway,and NF-κB signaling pathway,alongside elevated levels of apoptosis-related pathways,such as apoptosis,P53 pathway,and phagosome pathway.The significantly elevated genes in the TLR and NOD-like receptor signaling pathways,as well as in the apoptosis pathway,were validated through quantitative real-time PCR experiments in animal models.Validation from the GEO database revealed that only MYD88 concurred in both mouse pancreatic tissue and human AP peripheral blood,while TLR1,TLR7,RIPK3,and OAS2 genes exhibited marked elevation in human AP.The genes TUBA1A and GADD45A played significant roles in apoptosis within human AP.The transgenic mouse model hM3/Ptf1α(cre)successfully validated significant differential genes in the TLR and NOD-like receptor signaling pathways as well as the apoptosis pathway,indicating that these pathways represent shared pathological processes in AP across different models.CONCLUSION The TLR and NOD receptor signaling pathways play crucial roles in the inflammatory progression of AP,notably the MYD88 gene.Apoptosis holds a central position in the necrotic processes of AP,with TUBA1A and GADD45A genes exhibiting prominence in human AP.

Combination of allopurinol and hyperbaric oxygen therapy:A new treatment in experimental acute necrotizing pancreatitis?

AIM： To investigate the individual and combined effects of allopurinol and hyperbaric oxygen （HBO） therapy on biochemical and histopathological changes, oxidative stress, and bacterial translocation （BT） in the experimental rat acute pancreatitis （AP）. METHODS： Eighty-five Sprague-Dawley rats were included in the study. Fifteen of the eighty-five rats were used as controls （sham, Group I ）. AP was induced via intraductal taurocholate infusion in the remaining seventy rats. Rats that survived to induction of acute necrotizing pancreatitis were randomized into four groups. Group H received saline, Group m allopurinol, Group IV allopurinol plus HBO and Group v HBO alone. Serum amylase levels, oxidative stress parameters, BT and histopathologic scores were determined. RESULTS： Serum amylase levels were lower in Groups Ⅲ, Ⅳ and v compared to Group H （974 ± 110, 384 ± 40, 851 ＋ 56, and 1664 Ⅳ 234 U/L, respectively, P 〈 0.05, for all）. Combining the two treatment optionsrevealed significantly lower median [25-75 percentiles] histopathological scores when compared to individual administrations （13 [12.5-15] in allopurinol group, 9.5 [7-11.75] in HBO group, and 6 [4.5-7.5] in combined group, P 〈 0.01）. Oxidative stress markers were significantly better in all treatment groups compared to the controls. Bacterial translocation into the pancreas and mesenteric lymph nodes was lower in Groups m, iV and v compared to Group H （54%, 23%, 50% vs 100% for translocation to pancreas, and 62%, 46%, 58% vs 100% for translocation to mesenteric lymph nodes, respectively, P 〈 0.05 for all）. CONCLUSION： The present study confirms the benefit of HBO and allopurinol treatment when administered separately in experimental rat AP. Combination of these treatment options appears to prevent progression of pancreatic injury parameters more effectively.

Evidence for a role of mitogen-activated protein kinases in the treatment of experimental acute pancreatitis

Acute pancreatitis(AP) is an inflammatory disease characterized by acute inflammation and necrosis of the pancreatic parenchyma. AP is often associated with organ failure, sepsis, and high mortality. The pathogenesis of AP is still not well understood. In recent years several papers have highlighted the cellular and molecular events of acute pancreatitis. Pancreatitis is initiated by activation of digestive enzymes within the acinar cells that are involved in autodigestion of the gland, followed by a massive infiltration of neutrophils and macrophages and release of inflammatory mediators, responsible for the local and systemic inflammatory response. The hallmark of AP is parenchymal cell necrosis that represents the cause of the high morbidity and mortality, so that new potential therapeutic approaches are indispensable for the treatment of patients at high risk of complications. However, not all factors that determine the onset and course of the disease have been explained. Aim of this article is to review the role of mitogen-activated protein kinases in pathogenesis of acute pancreatitis.

Comment on "p38 MAPK inhibition alleviates experimental acute pancreatitis in mice"

To the Editor：I read with great interest the article by Cao et al[1] re- porting a potential therapeutic utility of p38 inhibitors for acute pancreatitis. Using a preclinical mouse model where acute pancreatitis was induced by administra- tion of cerulein （a cholecystokinin analog derived from the tree frog Litoria caerulea）, the authors reported that the p38 MAPK inhibitor SB203580, administered intra- peritoneally before and after the first administration of cerulein, relieved signs associated with acute pancreatitis, including decreased HSP60 and HSP70 expression, and serum IL-6, amylase and lipase activities. Although the study remains descriptive and pharmacodynamic aspects were not examined in depth, it still has a merit as it undoubtedly provides a basis for further investigation into the potential utility of targeting p38 signaling for acute pancreatitis, a common serious condition that can be life-threatening.