STC-1 alleviates airway inflammation by regulating epithelial cell apoptosis through the 5-LO pathway

Airway inflammation plays a key role in the pathogenesis and development of asthma. Stanniocalcin-1 (STC-1) has powerful antioxidant, anti-inflammatory and anti-apoptotic functions but its impact on the airway inflammation in asthma lacks evidence. Here, we investigated the effect and potential mechanism of STC-1 on airway inflammation through asthmatic mice model and lipopolysaccharide (LPS)-treated BEAS-2B cells. The data showed that STC-1 treatment before the challenge exerted protective effect on ovalbumin (OVA)-induced asthmatic mice, i.e., decreased the inflammatory cell infiltration, mucus secretion, cytokine levels, apoptosis levels, and p38 MAPK signaling. Additionally, STC-1 reduced 5-LO expression. Meanwhile, STC-1 decreased p38 MAPK signaling, cytokine production, mucin MUC5AC production, 5-LO expression and nuclear translocation, and LTB4 production in vitro. Ultimately, transforming growth factor $\beta$ (TGF- $\beta$ ), as a 5-LO inducer, reversed the anti-inflammatory and anti-apoptotic effects of STC-1 in BEAS-2B cells by up-regulating 5-LO expression. It reveals the potential of STC-1 to act as an additional therapy to mitigate airway inflammation in asthma and inhibit 5-LO expression.