Tricetin Reduces Inflammation and Acinar Cell Injury in Cerulein-Induced Acute Pancreatitis: The Role of Oxidative Stress-Induced DNA Damage Signaling

Abstract

Acute pancreatitis (AP) poses a worldwide challenge due to the growing incidence and its potentially life-threatening course and complications. Specific targeted therapies are not available, prompting the identification of new pathways and novel therapeutic approaches. Flavonoids comprise several groups of biologically active compounds with wide-ranging effects. The flavone compound, tricetin (TCT), has not yet been investigated in detail but sporadic reports indicate diverse biological activities. In the current study, we evaluated the potential protective effects of TCT in AP. TCT (30 μM) protected isolated primary murine acinar cells from the cytotoxic effects of cerulein, a cholecystokinin analog peptide. The protective effects of TCT were observed in a general viability assay (calcein ester hydrolysis), in an apoptosis assay (caspase activity), and in necrosis assays (propidium iodide uptake and lactate dehydrogenase release). The effects of TCT were not related to its potential antioxidant effects, as TCT did not protect against H2O2-induced acinar cell death despite possessing radical scavenging activity. Cerulein-induced expression of IL1β, IL6, and matrix metalloproteinase 2 and activation of nuclear factor-κB (NFκB) were reduced by 30 μM TCT. In vivo experiments confirmed the protective effect of TCT in a mouse model of cerulein-induced AP. TCT suppressed edema formation and apoptosis in the pancreas and reduced lipase and amylase levels in the serum. Moreover, TCT inhibited interleukin-1β (IL1β), interleukin-6 (IL6), and tumor necrosis factor-α (TNFα) expression in the pancreas and reduced the activation of the oxidative DNA damage sensor enzyme poly(ADP-ribose) polymerase-1 (PARP-1). Our data indicate that TCT can be a potential treatment option for AP.

OGG1 Inhibition Reduces Acinar Cell Injury in a Mouse Model of Acute Pancreatitis

“…Mice housed in Eurostandard Type II cages were fed ad-libitum with VRF1 (P) food and water. Acute pancreatitis was induced as previously described [ 21 ] with modification as detailed in [ 22 ]. Briefly male mice ( n = 18) were randomized into three groups: control, cerulein, and cerulein + TH5487.…”

“…Pancreatic acinar cells were isolated from male C57BL/6j mice and cultured in high glucose Dulbecco’s modified Eagle’s medium supplemented with 5% fetal bovine serum, 1% penicillin-streptomycin mixture, 0.25 mg/mL of trypsin inhibitor (Sigma-Aldrich, St. Louis, MO, USA), and 25 ng/mL of recombinant human epidermal growth factor (Sigma-Aldrich, St. Louis, MO, USA) as described previously [ 22 ].…”

“…Blood samples were taken by cardiac puncture and were centrifuged at 5000× g for 10 min at 4 °C. Serum α-amylase and lipase activities were measured using enzymatic assay kits as previously described [ 22 ].…”

“…Tissue myeloperoxidase (MPO) activity was measured as an indicator of neutrophil infiltration in the pancreas, as described previously [ 24 ] with modifications as detailed in [ 22 ].…”

“…Staining was scored by a pathologist blinded to the experimental design and identity of the samples. A scoring scheme from 0 to 3 for edema, leukocyte infiltration, and necrosis was used, as previously described [ 22 ].…”