Two indole-2-carboxamide derivatives attenuate lipopolysaccharide-induced acute lung injury by inhibiting inflammatory response

Acute lung injury (ALI) is the leading cause of mortality in the intensive care unit. Currently, there is no effective pharmacological treatment for ALI. In our previous study, we reported that Lg25 and Lg26, two indole-2-carboxamide derivatives, inhibited the lipopolysaccharide (LPS)-induced inflammatory cytokines in vitro and attenuated LPS-induced sepsis in vivo. In the present study, we confirmed data from previous studies that LPS significantly induced pulmonary edema and pathological changes in lung tissue, increased protein concentration and number of inflammatory cells in bronchoalveolar lavage fluids (BALF), and increased inflammatory cytokine TNF-α expression in serum and BALF, pro-inflammatory genes expression, and macrophages infiltration in lung tissue. However, pretreatment with Lg25 and Lg26 significantly attenuated the LPS-induced changes in mice. Taken together, these data indicate that the newly discovered indole-2-carboxamide derivatives could be particularly useful in the treatment of inflammatory diseases such as ALI.