Effects Of Prime-O-glucosylcimifugin On The Inflammatory Response And Acute Lung Injury In Mice

Inflammation is a rapid response to tissue injury and is characterized in the acutephase by increased blood flow and vascular permeability along with the accumulationof fluid, leucocytes, and inflammatory mediators such as cytokines (TNF-α, IL-1β,IL-6). The function of inflammation is to enclose injury, destroy invadingmicroorganisms and inactivate toxins, and to restore the tissue or organ for recovery.Bacterial endotoxin (lipopolysaccharide, LPS) is a complex glycolipid found in theouter membrane of all gram-negative bacteria, and is believed to play a crucial role ininduced cellular responses to gram-negative bacteria. One of the major reasons is thatendotoxin induces the disturbance of immune and inflammatory responses and causefever, hypotension, tissue damage, septic shock or even death. Although inflammatoryresponses have important role for host survival, it also leads to some acute andchronic inflammatory diseases. Acute and chronic inflammation are regarded as thecenters of many diseases, including systemic inflammatory response syndrome (SIRS),acute respiratory distress syndrome (ARDS), asthma, rheumatoid arthritis and chronicobstructive pulmonary disease (COPD) etc.Acute lung injury (ALI) is a serious clinical disease, it is not only the reflect ofsystemic inflammatory response syndrome mainly on the lungs, but also the firstmanifested organ dysfunction of multiple organ dysfunction syndrome, severe ALIcan develop into acute respiratory distress syndrome (ARDS). LPS is the major factorto lead to ALI and the root of ALI is the excessive and uncontrolled inflammatory response.Prime-O-glucosylcimifugin is an active chromone isolated from Saposhnikoviaroot which has been reported to have various activities, such as anti-convulsant,anticancer anti-inflammatory properties. The purpose of this study was to evaluateanti-inflammatory effect of Prime-O-glucosylcimifugin on RAW264.7cells and acutelung injury (ALI) induced by lipopolysaccharide in mice. In LPS stimulated cells, thelevels of cytokines in cell supernatant were measured by enzyme-linkedimmunosorbent assay (ELISA) and the mitogen-activated protein kinases (MAPK)signaling pathway activation and the phosphorylation of IκBα protein weredetermined by Western blot analysis. In addition, BALB/c mice receivedintraperitoneal injection of Prime-O-glucosylcimifugin1h before intranasalinstillation of lipopolysaccharide (LPS). Concentrations of tumor necrosis factor(TNF)-α, interleukin (IL)-1β and interleukin (IL)-6in bronchoalveolar lavage fluid(BALF) were measured by ELISA. Furthermore, Pulmonary histological changeswere evaluated by hematoxylin-eosin, myeloperoxidase (MPO) activity in the lungtissue and lung wet/dry weight ratios were observed.The results showed that RAW264.7macrophages treated with LPS aloneproduced signifcant amounts of TNF-α, IL-1β, IL-6and IL-10compared to thecontrol group. However, the production of TNF-α, IL-1β, and IL-6was inhibitedsignifcantly in a dose-dependent manner when the cells were treated withPrime-O-glucosylcimifugin. In contrast, the concentration of IL-10was siginificantlyincreased when the cells were treated with Prime-O-glucosylcimifugin.Prime-O-glucosylcimifugin inhibited the phosphorylation of ERK1/2, JNK and p38inLPS-induced cells and LPS-induced IκBɑ degradation was inhibited after pretreatment with Prime-O-glucosylcimifugin in a dose-dependent manner. In vivostudy, administration of Prime-O-glucosylcimifugin markedly suppressed theproduction of cytokine in BALF, neutrophilia and MPO activity, as well asameliorated the histopathologic changes in lung tissue produced by LPS challenge.These findings suggest that Prime-O-glucosylcimifugin had a promisinganti-inflammatory activity and a protective effect on LPS-induced ALI.