Objective To study the effect and mechanism of Xuebijing injection on sepsis-induced acute lung injury (ALI) in mice by regulating autophagy. Methods A total of 80 BALB/c male mice were randomly divided into control group, model group, Xuebijing group and Xuebijing+3-methyladenosine (3-MA) group, with 20 mice in each group. The control group received sham operation, while sepsis-induced ALI model was established in the later three groups by cecal ligation and puncture, on that basis, the Xuebijing group was given 10 mL/kg Xuebijing by intraperitoneal injection and the Xuebijing+3-MA group was given 10 mL/kg Xuebijing and 10 mg/kg autophagy inhibitor 3-mA by intraperitoneal injection. The cumulative survival rates of the four groups were observed 72 h after modeling, and the pathological changes of lung tissues, lung wet weight /dry weight ratios, inflammatory cytokines [tumor necrosis factor-α (TNF-α), interleukin (IL)-1 β, and IL-18] contents, numbers of autophagosome, and the protein expression levels of autophagy genes [microtubule-associated protein light chain3 (LC3)-Ⅱ/LC3-Ⅰand Beclin-1] were detected. Results In the control group, the 72-hour cumulative survival rate was 100%, the lung wet weight /dry weight ratio was 3.89±0.85, the TNF-α, IL-1β, and IL-18 contents were (0.83±0.14) ng/mg, (0.74±0.15) ng/mg, and (84.51±13.25) pg/mg, respectively, the number of autophagosome was (0.41±0.09)/field, and the expression levels of LC3-Ⅱ/LC3-Ⅰ and Beclin-1 were 0.20±0.04 and 0.17±0.03, respectively. In the model group, the lung tissue showed typical ALI pathological changes, the 72-hour cumulative survival rate (50%) was lower than that in the control group, and the lung wet weight /dry weight ratio (6.77±0.94), contents of TNF-α, IL-1β, and IL-18 [(3.15±0.76) ng/mg, (2.88±0.62) ng/mg, (274.62±45.58) pg/mg], autophagosome number [(3.14±0.55)/field], and expression levels of LC3-Ⅱ/LC3-Ⅰ and Beclin-1 (0.69±0.09, 0.35±0.06) were higher than those in the control group (P<0.05). In the Xuebijing group, the ALI pathological changes alleviated, the 72-hour cumulative survival rate (75%), autophagosome number [(5.77±0.75)/field], and expression levels of LC3-Ⅱ/LC3-Ⅰ and Beclin-1 (0.98±0.13, 0.62±0.08) were higher than those in the model group (P<0.05), and the lung wet weight /dry weight ratio (4.23±0.76) and contents of TNF-α, IL-1β, and IL-18 [(1.52±0.32) ng/mg, (1.29±0.30) ng/mg, (121.36±26.51) pg/mg] were lower than those in the model group (P<0.05). In the Xuebijing+3MA group, the ALI pathological changes aggravated, the 72-hour cumulative survival rate (55%), autophagosome number [(0.78±0.16)/field], and expression levels of LC3-Ⅱ/LC3-Ⅰ and Beclin-1 (0.37±0.05, 0.32±0.05) were lower than those in the Xuebijing group (P<0.05), and the lung wet weight /dry weight ratio (6.31±0.91) and contents of TNF-α, IL-1β, and IL-18 [(2.88±0.56) ng/mg, (2.41±0.58) ng/mg, (252.35±37.65) pg/mg] were higher than those in the Xuebijing group (P<0.05). Conclusion Xuebijing injection can reduce ALI induced by sepsis in mice, and activation of autophagy is the molecular mechanism.
Objective To investigate the protective effects of 6-O-desulfated heparin (6-DeH) on lung injury in septic mice by inhibiting the degradation of endothelial glycocalyx degradation. Methods BALB/c mice were divided into a sham group, a sepsis group, and a sepsis+6-DeH group. Cecal perforation surgery was used to establish sepsis model. After modeling, the sepsis+6-DeH group was given 2 mL of 5 g/L 6-DeH solution for nebulized inhalation, while the sham group and the sepsis group were given 2 mL of normal saline for nebulized inhalation, once every other day. Lung wet/dry weight ratio, protein concentration in bronchoalveolar lavage fluid (BALF), pathological changes of lung tissue, protein expression levels of CD31, thromboxomodulin (TM), hyaluronic acid (HA), heparan sulfate (HS), syndecan-1, glypican, angiopoietin 1 (Ang1), angiopoietin 2 (Ang2), Tie2 in lung tissue, co-localization of CD31 and syndecan-1 were detected at 14 days of intervention. Results Lung wet/dry weight ratio, protein concentration in BALF, protein expression level of Ang2 in lung tissue of the sepsis group were all significantly higher than those of the sham group, while protein expression levels of CD31, TM, HA, HS, syndecan-1, glypican, Ang1 and Tie2 in lung tissue were significantly lower than those of the sham group (all P<0.05). Lung wet/dry weight ratio, protein concentration in BALF, protein expression level of Ang2 in lung tissue of the sepsis+6-DeH group were all lower than those of the sepsis group, while protein expression levels of CD31, TM, HA, HS, syndecan-1, glypican, Ang1 and Tie2 in lung tissue were all higher than those of the sepsis group (all P<0.05). Immunofluorescence revealed co-localization of CD31 and syndecan-1 in lung tissue. Conclusions 6-DeH alleviates lung injury and inhibits degradation of endothelial glycocalyx in pulmonary blood vessels in septic mice. This effect is related to the regulation of the Ang/Tie2 pathway.
