Abstract
The present study investigated the effects of dual specificity phosphatase 1 (DUSP1) gene silencing using lentiviral vector-mediated small interfering (si)RNA on the release of proinflammatory cytokines through the regulation of the mitogen‑activated protein kinase (MAPK) signaling pathway in mice with acute pancreatitis (AP). Two siRNA‑DUSP1 sequences and one scramble siRNA sequence were designed, and the expression of DUSP1 was detected using western blot analysis to screen for the one with a higher interference rate. An AP mouse model was established, and KM mice were assigned to either a control, siRNA, AP, AP+PD98059, AP+scramble, AP+siRNA or AP+PD98059+siRNA group. The expression of proinflammatory cytokines, including tumor necrosis factor (TNF)‑α, interleukin (IL)‑1β and IL‑6, high mobility group box 1 (HMGB1), and S100A12 in serum samples were detected using an enzyme‑linked immunosorbent assay at 12, 24 and 48 h post‑modeling. The serum amylase levels were also detected. The expression levels of DUSP1, TNF‑α, IL‑1β, IL‑6, HMGB1, S100A12, phosphorylated (p‑) extracellular signal‑regulated kinase (ERK), p‑c‑Jun N‑terminal kinase (JNK), p‑p38, ERK, JNK and p38 in pancreatic, liver, kidney and lung tissues were detected using reverse transcription‑quantitative polymerase chain reaction and western blot analysis. Compared with the control group, the siRNA group demonstrated marginally upregulated serum amylase, lipase, urinary trypsinogen‑2, and proinflammatory cytokines, HMGB1 and S100A12 in serum and tissues, with no statistically significant difference, elevated expression levels of p‑ERK, p‑JNK and p‑p38, and decreased expression of DUSP1. The other five groups demonstrated increased expression levels of TNF‑α, IL‑1β, IL‑6, HMGB1, S100A12, amylase, lipase and urinary trypsinogen‑2 in serum, and increased expression levels of DUSP1, TNF‑α, IL‑1β, IL‑6, HMGB1, S100A12, p‑ERK, p‑JNK and p‑p38 in tissues. Compared with the AP group, the AP+PD98059+siRNA group had decreased expression of DUSP1 in tissues, whereas the AP+PD98059 group had decreased serum expression levels of TNF‑α, IL‑1β, IL‑6, HMGB1, S100A12 and amylase, lipase and urinary trypsinogen‑2. The expression levels of TNF‑α, IL‑1β, IL‑6, HMGB1, S100A12, p‑ERK, p‑JNK, p‑p38 in tissues, and edema of pancreatic tissue were alleviated, whereas the opposite results were observed in the AP+siRNA group with the decreased expression of DUSP1. The results suggested that DUSP1 gene silencing promoted the release of proinflammatory cytokines through activation of the MAPK signaling pathway in mice with AP.