Knockdown of ORM2 improves cerulein-induced acute pancreatitis in vitro via the p38 MAPK signaling pathway

The pathophysiology of acute pancreatitis remains poorly understood, and it is a severe inflammatory pancreatic disease that is becoming more widespread globally. The protein orosomucoid 2 (ORM2) is closely linked with tissue injury and inflammation. The purpose of this study was to investigate ORM2 expression in pancreatic acinar cells and its potential regulatory function in the regulation of inflammation and damage in acute pancreatitis. The model was established by culturing rat pancreatic acinar AR42J cells with 10 nM azuretin. Lentivirus was used to transfect AR42J cells to generate negative control and ORM2 knockdown cell lines. In order to track changes in ORM2 expression, cell proliferation, apoptosis, and the production of inflammatory cytokines in AR42J cells, this study carried out a number of tests. Western blotting showed expression changes in the p38 mitogen-activated protein kinases (MAPK) pathway. The results showed that ORM2 expression is up-regulated in acute pancreatitis in vitro, and knocking down ORM2 reversed the decrease in survival rate, the increase in apoptosis and the elevated inflammatory factor levels in AR42J cells induced by cerulein. Knockdown of ORM2 also inhibited the phosphorylation of p38 and extracellular signal-regulated kinase (ERK). In summary, ORM2 may significantly influence damage and inflammation in the in vitro rat pancreatic acinar cells model of acute pancreatitis by modulating the phosphorylation levels of p38 MAPK signaling.

Acute pancreatitis; Inflammation; ORM2; Pancreatic acinar cells; p38 MAPK

[1] Mederos MA, Reber HA, Girgis MD. Acute pancreatitis: a review. JAMA. 2021; 325: 382–390.

[2] Szatmary P, Grammatikopoulos T, Cai W, Huang W, Mukherjee R, Halloran C, et al. Acute pancreatitis: diagnosis and treatment. Drugs. 2022; 82: 1251–1276.

[3] Wang D, Han S, Lv G, Hu Y, Zhuo W, Zeng Z, et al. Pancreatic acinar cells-derived sphingosine-1-phosphate contributes to fibrosis of chronic pancreatitis via inducing autophagy and activation of pancreatic stellate cells. Gastroenterology. 2023; 165: 1488–1504.e20.

[4] Lv H, Liu X, Zhou H. USP25 upregulation boosts GSDMD-mediated pyroptosis of acinar cells in acute pancreatitis. Shock. 2022; 58: 408–416.

[5] Li H, Xu Y, Zhou X, Jin T, Wang Z, Sun Y, et al. DIA-based proteomic analysis of plasma protein profiles in patients with severe acute pancreatitis. Molecules. 2022; 27: 3880.

[6] Zhou B, Luo Y, Ji N, Hu C, Lu Y. Orosomucoid 2 maintains hepatic lipid homeostasis through suppression of de novo lipogenesis. Nature Metabolism. 2022; 4: 1185–1201.

[7] Kim KM, Lee KG, Lee S, Hong BK, Yun H, Park YJ, et al. The acute phase reactant orosomucoid-2 directly promotes rheumatoid inflammation. Experimental & Molecular Medicine. 2024; 56: 890–903.

[8] Li L, Chen J, Sun H, Niu Q, Zhao Y, Yang X, et al. Orm2 deficiency aggravates high‐fat diet‐induced obesity through gut microbial dysbiosis and intestinal inflammation. Molecular Nutrition & Food Research. 2024; 68: e2300236.

[9] Li L, Sun H, Chen J, Ding C, Yang X, Han H, et al. Mitigation of non-alcoholic steatohepatitis via recombinant Orosomucoid 2, an acute phase protein modulating the Erk1/2-PPARγ-Cd36 pathway. Cell Reports. 2023; 42: 112697.

[10] Cao M, Day AM, Galler M, Latimer HR, Byrne DP, Foy TW, et al. A peroxiredoxin-P38 MAPK scaffold increases MAPK activity by MAP3K-independent mechanisms. Molecular Cell. 2023; 83: 3140–3154.e7.

[11] Qu J, Xie H, Xiao Y, Zhang Y, Hu Z, Wang J, et al. The inhibition of p38 MAPK blocked inflammation to restore the functions of rat meibomian gland epithelial cells. Experimental Eye Research. 2023; 231: 109470.

[12] Zhang X, Wang H, Yang X, Lin Z, Shi N, Chen C, et al. Alleviation of acute pancreatitis-associated lung injury by inhibiting the p38 mitogen-activated protein kinase pathway in pulmonary microvascular endothelial cells. World Journal of Gastroenterology. 2021; 27: 2141–2159.

[13] Song TJ, Ke J, Chen F, Zhang JY, Zhang C, Chen HY. Effect of SNHG11/miR-7-5p/PLCB1 axis on acute pancreatitis through inhibiting p38MAPK pathway. Cells. 2022; 12: 65.

[14] Jo M, Kim JH, Song GJ, Seo M, Hwang EM, Suk K. Astrocytic orosomucoid-2 modulates microglial activation and neuroinflammation. The Journal of Neuroscience. 2017; 37: 2878–2894.

[15] Murphy JA, Criddle DN, Sherwood M, Chvanov M, Mukherjee R, McLaughlin E, et al. Direct activation of cytosolic Ca2+ signaling and enzyme secretion by cholecystokinin in human pancreatic acinar cells. Gastroenterology. 2008; 135: 632–641.

[16] Liu K, Liu J, Zou B, Li C, Zeh HJ, Kang R, et al. Trypsin-mediated sensitization to ferroptosis increases the severity of pancreatitis in mice. Cellular and Molecular Gastroenterology and Hepatology. 2022; 13: 483–500.

[17] Han F, Ding ZF, Shi XL, Zhu QT, Shen QH, Xu XM, et al. Irisin inhibits neutrophil extracellular traps formation and protects against acute pancreatitis in mice. Redox Biology. 2023; 64: 102787.

[18] Kim SM, Park EJ, Lee HJ. Nuciferine attenuates lipopolysaccharide-stimulated inflammatory responses by inhibiting p38 MAPK/ATF2 signaling pathways. Inflammopharmacology. 2022; 30: 2373–2383.

[19] Zhang J, Wang Y, Liu B, Liu X, Xu Z. Activity of Ligustrum vulgare L extracts against acute pancreatitis in murine models by regulation of p38 MAPK and NF-κB signaling pathways. Saudi Journal of Biological Sciences. 2022; 29: 273–278.

[20] Cao MH, Xu J, Cai HD, Lv ZW, Feng YJ, Li K, et al. p38 MAPK inhibition alleviates experimental acute pancreatitis in mice. Hepatobiliary & Pancreatic Diseases International. 2015; 14: 101–106.

[21] Liu H, Xu X, Li J, Liu Z, Xiong Y, Yue M, et al. Overexpression of plakophilin2 mitigates capillary leak syndrome in severe acute pancreatitis by activating the p38/MAPK signaling pathway. Journal of Inflammation Research. 2024; 17: 4129–4149.