Sakuranetin is the main isolate
flavonoid from Baccharis retusa (Asteraceae) leaves and exhibits anti-inflammatory and antioxidative activities.
Acute respiratory distress syndrome is an acute failure of the respiratory system for which effective treatment is urgently necessary. This study investigated the preventive and
therapeutic effects of
sakuranetin on
lipopolysaccharide (LPS)-induced
acute lung injury (ALI) in mice. Animals were treated with intranasal
sakuranetin 30 min before or 6 h after instillation of LPS. Twenty-four hours after ALI was induced, lung function,
inflammation, macrophages population markers,
collagen fiber deposition, the extent of oxidative stress, and the expression of matrix metalloprotease-9 (MMP-9), tissue inhibitor of MMP-9 (TIMP-1) and NF-κB were evaluated. The animals began to show lung alterations 6 h after LPS instillation, and these changes persisted until 24 h after LPS administration. Preventive and therapeutic treatment with
sakuranetin reduced the neutrophils in the peripheral blood and in the bronchial alveolar lavage.
Sakuranetin treatment also reduced macrophage populations, particularly that of M1-like macrophages. In addition, sakurnaetin treatment reduced
keratinocyte-derived chemokines (IL-8 homolog) and NF-κB levels,
collagen fiber formation, MMM-9 and TIMP-1-positive cells, and oxidative stress in lung tissues compared with LPS animals treated with vehicle. Finally,
sakuranetin treatment also reduced total
protein, and the levels of TNF-α and IL-1β in the lung. This study shows that
sakuranetin prevented and reduced
pulmonary inflammation induced by LPS. Because
sakuranetin modulates oxidative stress, the NF-κB pathway, and lung function, it may constitute a novel therapeutic candidate to prevent and treat ALI.