title: Cystathionine-gamma-lyase gene silencing with siRNA in monocytes/macrophages protects mice against acute pancreatitis.
abstract: Hydrogen sulphide (H2S) is an endogenous inflammatory mediator produced by cystathionine-γ-lyase (CSE) in monocytes/macrophages. To determine the role of H2S and macrophages in inflammation, we used small interference RNA (siRNA) to target the CSE gene and investigated its effect in a mouse model of acute pancreatitis. Acute pancreatitis is characterised by increased levels of plasma amylase, myeloperoxidase (MPO) activity and pro-inflammatory cytokines and chemokines in the pancreas and lung. SiRNA treatment attenuated inflammation in the pancreas and lungs of mice following caerulein-induced acute pancreatitis. MPO activity increased in caerulein-induced acute pancreatitis (16.21 ± 3.571 SD fold increase over control) and treatment with siRNA significantly reduced this (mean 3.555 ± 2.522 SD fold increase over control) (p < 0.0001). Similarly, lung MPO activity increased following treatment with caerulein (3.56 ± 0.941 SD fold increase over control) while siRNA treatment significantly reduced MPO activity (0.8243 ± 0.4353 SD fold increase over control) (p < 0.0001). Caerulein treatment increased plasma amylase activity (7094 ± 207 U/l) and this significantly decreased following siRNA administration (5895 ± 115 U/l) (p < 0.0001). Cytokine and chemokine levels in caerulein-induced acute pancreatitis reduced following treatment with siRNA. For example, siRNA treatment significantly decreased pancreatic and lung monocyte chemoattractant protein (MCP)-1 (169.8 ± 59.75 SD; 90.01 ± 46.97 SD pg/ml, respectively) compared to caerulein-treated mice (324.7 ± 103.9 SD; 222.8 ± 85.37 SD pg/ml, pancreas and lun,g respectively) (p < 0.0001). These findings show a crucial pro-inflammatory role for H2S synthesised by CSE in macrophages in acute pancreatitis and suggest CSE gene silencing with siRNA as a potential therapeutic approach for this condition.
authors.affiliation: Inflammation Research Group, Department of Pathology, University of Otago, 2 Riccarton Avenue, P.O. Box 4345, Christchurch, 8140, New Zealand.
authors.forename: A
authors.initials: A
authors.lastname: Badiei
authors.affiliation: Infection Research Group, Department of Pathology, University of Otago, Christchurch, New Zealand.
authors.forename: S T
authors.initials: ST
authors.lastname: Chambers
authors.affiliation: Inflammation Research Group, Department of Pathology, University of Otago, 2 Riccarton Avenue, P.O. Box 4345, Christchurch, 8140, New Zealand.
authors.forename: R R
authors.initials: RR
authors.lastname: Gaddam
authors.affiliation: Inflammation Research Group, Department of Pathology, University of Otago, 2 Riccarton Avenue, P.O. Box 4345, Christchurch, 8140, New Zealand.
authors.forename: R
authors.initials: R
authors.lastname: Fraser
authors.affiliation: Inflammation Research Group, Department of Pathology, University of Otago, 2 Riccarton Avenue, P.O. Box 4345, Christchurch, 8140, New Zealand. madhav.bhatia@otago.ac.nz.
authors.forename: M
authors.initials: M
authors.lastname: Bhatia
mesh_terms: D000681:Amylases / Q000097:blood; D000818:Animals; D001774:Blood Chemical Analysis; D002108:Ceruletide / Q000008:administration & dosage / Q000633:toxicity; D003542:Cystathionine gamma-Lyase / Q000037:antagonists & inhibitors* / Q000235:genetics*; D016207:Cytokines / Q000097:blood; D004195:Disease Models, Animal; D020868:Gene Silencing; D006862:Hydrogen Sulfide / Q000378:metabolism*; D018836:Inflammation Mediators / Q000378:metabolism*; D008168:Lung / Q000473:pathology; D051379:Mice; D009000:Monocytes / Q000201:enzymology* / Q000276:immunology; D010179:Pancreas / Q000473:pathology; D019283:Pancreatitis, Acute Necrotizing / Q000139:chemically induced / Q000473:pathology / Q000517:prevention & control*; D009195:Peroxidase / Q000032:analysis; D034741:RNA, Small Interfering / Q000378:metabolism*
chemical_list: D016207:Cytokines; D018836:Inflammation Mediators; D034741:RNA, Small Interfering; D002108:Ceruletide; D009195:Peroxidase; D000681:Amylases; D003542:Cystathionine gamma-Lyase; D006862:Hydrogen Sulfide
keywords: Acute pancreatitis; Cystathionine-γ-lyase; Hydrogen sulphide; Small interference RNA