宁海白枇杷叶水提物通过抗炎和调控肠道菌群缓解小鼠急性肺炎OA

To investigate the protective effects and mechanisms of the aqueous extract of Ninghai Bai loquat leaves a-gainst acute pneumonia,a mouse model of lipopolysaccharide(LPS)-induced acute pneumonia was established.Cell viability assays,lung histopathological observation,wet-to-dry weight ratio(W/D)measurement,assessment of oxi-dative stress and inflammatory cytokine levels,and 16S rRNA sequencing-based gut microbiota analysis were per-formed.The results showed that the loquat leaf aqueous extract alleviated LPS-induced lung epithelial cell injury in a dose-dependent manner.Pretreatmentwiththeextract(200,400 mg·kg-1)hadnosignificanteffectonorgancoeffi-cients in LPS-induced mice,but significantly(p<0.01)decreased the lung W/D and ameliorated pathological dam-age such as alveolar wall thickening and inflammatory cell infiltration.No significant changes were observed in ma-londialdehyde(MDA)content and superoxide dismutase(SOD)activity in lung tissue,whereas myeloperoxidase(MPO)activity and levels of the pro-inflammatory cytokines IL-1β,IL-6,and TNF-α were reduced,and glutathione peroxidase(GPx)activity was increased.Gut microbiota analysis revealed that the loquat leaf aqueous extract amel-iorated LPS-induced microbial dysbiosis by increasing the relative abundance of the phylum Bacillota,decreasing that of Bacteroidota,and augmenting the relative abundances of beneficial genera such as Allobaculum,Ileibacterium and Adlercreutzia.In conclusion,the aqueous extract of Ninghai Bai loquat leaves exerts a protective effect against LPS-induced acute pneumonia in mice,which may be associated with the inhibition of oxidative stress and inflammatory responses and the regulation of gut microbiota homeostasis.