Baicalin Ameliorates Lung Injury in Rats by Inhibiting NLRP3 Inflammasome Activation via NF-[Formula: see text]B Signaling Pathway.

Abstract

Hemorrhagic shock (HS) is defined as a reduction in tissue oxygenation and organ dysfunction due to severe blood loss. Lung injury is a frequent complication of HS. Baicalin, isolated from Radix Scutellariae, has been reported to profile the antitumor, anti-oxidative, anti-inflammatory, and antibacterial roles in various pathological processes. Nevertheless, the effects of baicalin on HS-induced lung injury are unclear. This study aims to examine the therapeutic effects of baicalin on lung injury. We first established the lung injury rat models by withdrawing blood in the femoral artery followed by resuscitation. A pathological analysis showed that HS-administrated rats presented severe capillary leakage and pulmonary edema, while baicalin therapy alleviated the symptoms. Baicalin therapy reduced the number of macrophages and neutrophils in bronchoalveolar lavage fluid and decreased the expression and activity of myeloperoxidase (neutrophile infiltration marker) in the lung tissues of HS rats, indicating that baicalin alleviated HS-induced infiltration of inflammatory cells. The secretion of inflammatory cytokines, including interleukin (IL)-1[Formula: see text], IL-6, IL-18, and tumor necrosis factor [Formula: see text] (TNF-[Formula: see text]), as well as the activation of the nucleotide-binding oligomerization domain-like receptor family pyrin domain-containing-3 (NLRP3) inflammasome, were inhibited by baicalin administration. Furthermore, we found that the NF-[Formula: see text]B pathway, a canonical pro-inflammatory pathway, was also blocked after treatment with baicalin in HS-evoked rats, as indicated by the decreased expression of p65 and p65 phosphorylation in the lung tissues. In summary, we infer that baicalin may exert a protective role in HS-induced lung injury by suppressing the activation of NLRP3 inflammasome via the NF-[Formula: see text]B pathway.