Objective:To explore the protective mechanism of Xuebijing injection (referred to as Xuebijing) on sepsis-associated acute respiratory distress syndrome (ARDS).Methods:① Animal experiments: 100 mice were randomly(random number) divided into 4 groups, including sham operation (Sham) group, cecal ligation and puncture (CLP) group, CLP+low-dose Xuebijing (L-XBJ) group, and CLP+high-dose Xuebijing (H-XBJ) group. The survival rate, lung histological changes, lung wet/dry (W/D) ratio, cell count and protein concentration in bronchoalveolar lavage fluids (BALF), inflammatory factors levels in serum, oxidative stress indicators, cell apoptosis, and key proteins of HIF-1α/p38 MAPK/NF-κB signaling pathway were measured. ② Cell experiments: Mouse alveolar macrophages (MH-S) were cultured in vitro and divided into 6 groups, including control (Con) group, lipopolysaccharide (LPS) group, LPS+L-XBJ group, and LPS+H-XBJ group, LPS+H-XBJ+ dimethyloxallyl glycine (DMOG, HIF-1α activator) group, LPS+H-XBJ+ 2-methoxyestradiol (2ME2, HIF-1α inhibitor) group. The effects of Xuebijing on inflammatory factors, oxidative stress, and cell apoptosis and their relationship with HIF-1α/p38 MAPK/NF-κB signaling pathway were detected.Results:Xuebijing increased the survival rate of mice with sepsis-associated ARDS, relieved lung tissue damage [lung injury score: CLP group (8.778±0.588), CLP+L-XBJ group (5.833±0.310), and CLP+H-XBJ group (4.750±0.246)], alleviated lung W/D ratio, and decreased pneumonia cell infiltration and protein exudation (all P<0.05). Additionally, Xuebijing treatment also diminished the expression of inflammatory factors (TNF-α, IL-1β, and IL-6), intracellular reactive oxygen species (ROS) accumulation, malondialdehyde (MDA) formation, superoxide dismutase (SOD) depletion, and cell apoptosis in LPS-induced MH-S cells and CLP-induced sepsis-associated ARDS mice (all P<0.05). Furthermore, mechanistic investigation further clarified the effects of Xuebijing on inflammation, oxidative stress, and cell apoptosis through the HIF-1α/p38 MAPK/NF-κB signaling pathway. Conclusions:Xuebijing can exert anti-inflammatory, anti-oxidative, and anti-apoptotic effects by suppressing the HIF-1α/p38 MAPK/NF-κB signaling pathway, thereby conferring protection against sepsis-associated ARDS.

Objective To investigate the effect of fluid shear(FS)on apoptosis of glomerular epithelial cells(GECs)and the role of Piezo 1 protein in it.Methods GECs(glomerular epithelial cells)of SD rat were cul-tured.Fluid shear stimulation was simulated by a Flexcell-T5000 tensiometer.Apoptosis level was detected by flow cytometry.The expression of Piezo 1 proteins in GECs was detected by immunofluorescence staining.The activating of Piezo 1 channels by fluid shear was observed using Ca2+indicator(Cal-590 AM).The effect of Piezo 1 on apop-tosis in GECs was analyzed after modulating the function or expression of Piezo 1 protein using the chemical activa-tor Yoda1,the inhibitor GsMtx 4 was regulated by lentivirus Lv-shPiezo 1.Results Compared with the blank controlgroup,apoptosis increased in the fluid shear group(P＜0.05).The rate of apoptosis increased with the enhancing of fluid shear strength;Piezo 1 was commonly expressed in GECs.Fluid shear activated Piezo 1 chan-nel and enhanced expression of Piezo 1.The agonist Yoda1 promoted the apoptosis of GECs GsMtx 4 inhibited the apoptosis induced by fluid shear.Lv-shPiezo 1 knocked down the expression of Piezo 1 in GECs and the apoptosis rate of GECs in the knockdown group was reduced as compared to that in the control group and Lv-Ctrl group(P＜0.05).Conclusions Fluid shear may promote apoptosis of GECs by activation of Piezo 1 and by enhancing expression of Piezo 1.