Ulinastatin attenuates LPS-induced inflammation in mouse macrophage RAW264.7 cells by inhibiting the JNK/NF-κB signaling pathway and activating the PI3K/Akt/Nrf2 pathway

Abstract

Ulinastatin (UTI) is a broad-spectrum serine protease inhibitor isolated and purified from human urine with strong anti-inflammatory and cytoprotective actions, which is widely used for the treatment of various diseases, such as pancreatitis and sepsis. Although the therapeutic effects of UTI are reported to be associated with a variety of mechanisms, the signaling pathways mediating the anti-inflammatory action of UTI remain to be elucidated. In the present study we carried out a systematic study on the anti-inflammatory and anti-oxidative mechanisms of UTI and their relationships in LPS-treated RAW264.7 cells. Pretreatment with UTI (1000 and 5000 U/mL) dose-dependently decreased the mRNA levels of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α, iNOS) and upregulated anti-inflammatory cytokines (IL-10 and TGF-β1) in LPS-treated RAW264.7 cells. UTI pretreatment significantly inhibited the nuclear translocation of NF-κB by preventing the degradation of IκB-α. UTI pretreatment only markedly inhibited the phosphorylation of JNK at Thr183, but it did not affect the phosphorylation of JNK at Tyr185, ERK-1/2 and p38 MAPK; JNK was found to function upstream of the IκB-α/NF-κB signaling pathway. Furthermore, UTI pretreatment significantly suppressed LPS-induced ROS production by activating PI3K/Akt pathways and the nuclear translocation of Nrf2 via promotion of p62-associated Keap1 degradation. However, JNK was not involved in mediating the anti-oxidative stress effects of UTI. In summary, this study shows that UTI exerts both anti-inflammatory and anti-oxidative effects by targeting the JNK/NF-κB and PI3K/Akt/Nrf2 pathways.

Ulinastatin prevents hyperoxia-induced lung injury on newborn rats by downregulating TNF-α and inhibiting macrophage infiltration

“…Previous reports have documented that UTI may reduce rat lung injury and protect the lung from damage, induced by H2S, by inhibiting ROS. 11 However, in our study, no significant differences were identified in SOD and MDA levels in…”

“…The dosage and schedule of UTI used in the following publications were referred to our study. 10,11 Every day, the chambers were opened at fixed time to 11 perform water and food supply and drug treatment, and all these operations were conducted within 1 hour. Maternal rats were daily exchanged with rat from control group to avoid poor feeding influenced by oxygen toxicity.…”

Pharmacological activation of REV-ERBα represses LPS-induced microglial activation through the NF-κB pathway

“…After LPS stimulation, IκB was phosphorylated and degraded. Thus, the NF-κB nuclear translocation signal was subsequently exposed [16]. We therefore examined the levels of total and phosphorylated forms of IκBα.…”

Immunomodulatory activity of Ganoderma lucidum immunomodulatory protein via PI3K/Akt and MAPK signaling pathways in macrophage RAW264.7 cells

“…A preliminary yeast two-hybrid experiment showed that rFIP-glu did not interact with an extracellular part of TLR2 (Data not shown), suggesting TLR2 possibly was not a receptor of rFIP-glu as well. It is noteworthy that some active substances can activate all of these pathways (34, 57, 88), while some can only activate one or more (30, 87, 94). We next used specific PI3K/Akt and MAPKs pathway inhibitors to clarify whether these signaling pathways were involved in macrophage activation induced by rFIP-glu.…”

“…Heme oxygenase-1 (HO-1) is an anti-inflammatory enzyme and attenuates the inflammatory response (95), which can be regulated by nuclear factor erythroid 2-related factor 2 (Nrf2) in the inflammatory response (96). The Induction of HO-1 can be though MAPK and PI3K signaling pathways (94, 97, 98). In the present study, mRNA level of HO-1 was significantly increased in rFIP-glu-induced RAW264.7 cells (Fig.…”