Objective:

2

To investigate the effects of Danmu Extract Syrup (DMS) on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice and explore the mechanism.

Methods:

2

Seventy-two male Balb/C mice were randomly divided into 6 groups according to a random number table (

n

=12)

including control (normal saline)

LPS (5 mg/kg)

LPS+DMS 2.5 mL/kg

LPS+DMS 5 mL/kg

LPS+DMS 10 mL/kg

and LPS+Dexamethasone (DXM

5 mg/kg) groups. After pretreatment with DMS and DXM

the ALI mice model was induced by LPS

and the bronchoalveolar lavage fluid (BALF) were collected to determine protein concentration

cell counts and inflammatory cytokines. The lung tissues of mice were stained with hematoxylin-eosin

and the wet/dry weight ratio (W/D) of lung tissue was calculated. The levels of tumor necrosis factor-α (TNF-α)

interleukin (IL)-6 and IL-1β in BALF of mice were detected by enzyme linked immunosorbent assay. The expression levels of Claudin-5

vascular endothelial (VE)-cadherin

vascular endothelial growth factor (VEGF)

phospho-protein kinase B (p-Akt) and Akt were detected by Western blot analysis.

Results:

2

DMS pre-treatment significantly ameliorated lung histopathological changes. Compared with the LPS group

the W/D ratio and protein contents in BALF were obviously reduced after DMS pretreatment (

P

<

0.05 or

P

<

0.01). The number of cells in BALF and myeloperoxidase (MPO) activity decreased significantly after DMS pretreatment (

P

<

0.05 or

P

<

0.01). DMS pre-treatment decreased the levels of TNF-α

IL-6 and IL-1β (

P

<

0.01). Meanwhile

DMS activated the phosphoinositide 3-kinase/protein kinase B (PI3K/Akt) pathway and reversed the expressions of Claudin-5

VE-cadherin and VEGF (

P

<

0.01).

Conclusions:

2

DMS attenuated LPS-induced ALI in mice through repairing endothelial barrier. It might be a potential therapeutic drug for LPS-induced lung injury.