Adipose tissue-derived stem cells attenuate acute lung injury through eNOS and eNOS-derived NO

Acute lung injury (ALI) is among the most common causes of mortality in intensive care units. Recent in vivo and in vitro studies have suggested that mesenchymal stem cells (MSCs) attenuate pulmonary edema and inflammatory factors, but the mechanisms of the effects of MSCs on pulmonary vascular function remain unknown. It is believed that nitric oxide (NO) and endothelial nitric oxide synthase (eNOS) play an essential role in the regulation of vascular function and homeostasis. In the present study, we investigated the effect of adipose tissue-derived stem cells (ADSCs) on pulmonary microvascular endothelial cells (PMVECs) and the lung in a lipopolysaccharide (LPS)-induced ALI model in vitro and in vivo. Our results showed that ADSCs were able to attenuate the severity of ALI and pulmonary edema. Increased expression of the eNOS protein was also observed in pulmonary PMVECs and in the lung following treatment with ADSCs. Furthermore, ADSCs increased the concentration of eNOS-derived NO to remodel ALI. The results suggest that ADSCs may be a promising candidate for ALI treatment through interaction with eNOS and eNOS-derived NO.