Letter to the editor regarding the article 'MiR-216a alleviates LPS-induced acute lung injury via regulating JAK2/STAT3 and NF-қB signaling'

Action of Tofacitinib in a Rat Model of Synovitis

Purpose: To evaluate effects and mechanism of tofacitinib in treatment of rheumatoid arthritis (RA) model rats. Materials and Methods: Dividing 27 rats into 3 groups: NC (normal control), Model (RA model) and Tofacitinib (RA model rats treated with tofacitinib) groups. Observation joint swelling and articular synovium pathology by HE staining, IL-1β, IL-6, IL-10 and TNF-α levels by ELISA assay, JAK2, STAT3 and NF-κB(p65) proteins by IHC and WB assay. Results: Compared with NC group, joint swelling, histopathological score IL-1β, IL-6, IL-10 and TNF-α significantly deteriorated (P < 0.001, respectively); by IHC and WB assay, JAK2, STAT3 and NF-κB(p65) proteins expression were significantly up-regulation in joint synovial tissue in model group (P < 0.001, respectively). With tofacitinib supplement, joint swelling, histopathological score IL-1β, IL-6, IL-10 and TNF-α significantly improved (P < 0.001, respectively); by IHC and WB assay, JAK2, STAT3 and NF-κB(p65) proteins expression significantly down-regulation in joint synovial tissue in Tofacitinib group (P < 0.001, respectively). Conclusion: Tofacitinib could improve RA via regulation JAK2/STAT3/NF-κB(p65) pathway in vivo study.

Daphnetin ameliorates acute lung injury in mice with severe acute pancreatitis by inhibiting the JAK2-STAT3 pathway

Severe acute pancreatitis (SAP) is often associated with pulmonary inflammation leading to acute lung injury. Daphnetin, a natural coumarin derivative, has been reported to exert anti-inflammatory effects. Here, we explored the effect and possible mechanism of daphnetin in a mouse model of SAP-associated lung injury induced by an intraperitoneal injection of L-arginine. The severity of pancreatic and lung injury is determined by histology and its score. Immunostaining of inflammatory and apoptotic cells was used to demonstrate lung tissue inflammation and apoptosis; ELISA analysis of serum and tissue cytokine levels; and western blotting and immunohistochemical staining for the activated Janus kinase 2 (JAK2)-signal transducer and activator of transcription protein 3 (STAT3) signalling pathway in lung tissues. Daphnetin pretreatment significantly reduced SAP-induced pancreatic and lung tissue damage, reduced interleukin-6 and tumour necrosis factor-α concentrations in both serum and lung tissues, reduced serum amylase and myeloperoxidase activities, and reduced macrophage (CD11b) and neutrophil (Ly6G) infiltration and cell apoptosis in the lung tissue. Moreover, SAP-induced phosphorylation of JAK2 and STAT3 in the lung tissue was also significantly diminished by the daphnetin pretreatment. These results indicated that daphnetin reduces SAP-associated lung tissue damage, likely by inhibiting the activation of JAK2-STAT3 signalling.