Punica granatum L. Leaf Extract Attenuates Lung Inflammation in Mice with Acute Lung Injury

Abstract EN

The hydroalcoholic extract of Punica granatum (pomegranate) leaves was previously demonstrated to be anti-inflammatory in a rat model of lipopolysaccharide- (LPS-) induced acute peritonitis.

Here, we investigated the anti-inflammatory effects of the ethyl acetate fraction obtained from the pomegranate leaf hydroalcoholic extract (EAFPg) on the LPS-induced acute lung injury (ALI) mouse model.

Male Swiss mice received either EAFPg at different doses or dexamethasone (per os) prior to LPS intranasal instillation.

Vehicle-treated mice were used as controls.

Animals were culled at 4 h after LPS challenge, and the bronchoalveolar lavage fluid (BALF) and lung samples were collected for analysis.

EAFPg and kaempferol effects on NO and cytokine production by LPS-stimulated RAW 264.7 macrophages were also investigated.

Pretreatment with EAFPg (100–300 mg/kg) markedly reduced cell accumulation (specially neutrophils) and collagen deposition in the lungs of ALI mice.

The same animals presented with reduced lung and BALF TNF-α and IL-1β expression in comparison with vehicle controls (p<0.05).

Additionally, incubation with either EAFPg or kaempferol (100 μg/ml) reduced NO production and cytokine gene expression in cultured LPS-treated RAW 264.7 macrophages.

Overall, these results demonstrate that the prophylactic treatment with EAFPg attenuates acute lung inflammation.

We suggest this fraction may be useful in treating ALI.