Catalpol ameliorates LPS-induced endometritis by inhibiting inflammation and TLR4/NF-κB signaling

Catalpol is the main active ingredient of an extract from Radix rehmanniae,which in a previous study showed a protective effect against various types of tissue injury.However,a protective effect of catalpol on uterine inflammation has not been reported.In this study,to investigate the protective mechanism of catalpol on lipopolysaccharide(LPS)-induced bovine endometrial epithelial cells(bEECs)and mouse endometritis,in vitro and in vivo inflammation models were established.The Toll-like receptor 4(TLR4)/nuclear factor-κB(NF-κB)signaling pathway and its downstream inflammatory factors were detected by enzyme-linked immunosorbent assay(ELISA),quantitative real-time polymerase chain reaction(qRT-PCR),western blot(WB),and immunofluorescence techniques.The results from ELISA and qRT-PCR showed that catalpol dose-dependently reduced the expression of pro-inflammatory cytokines such as tumor necrosis factorα(TNF-α),interleukin(IL)-1β,and IL-6,and chemokines such as C-X-C motif chemokine ligand 8(CXCL8)and CXCL5,both in bEECs and in uterine tissue.From the experimental results of WB,qRT-PCR,and immunofluorescence,the expression of TLR4 and the phosphorylation of NF-κB p65 were markedly inhibited by catalpol compared with the LPS group.The inflammatory damage to the mouse uterus caused by LPS was greatly reduced and was accompanied by a decline in myeloperoxidase(MPO)activity.The results of this study suggest that catalpol can exert an anti-inflammatory impact on LPS-induced bEECs and mouse endometritis by inhibiting inflammation and activation of the TLR4/NF-κB signaling pathway.

Erratum to: Catalpol ameliorates LPS-induced endometritis by inhibiting inflammation and TLR4/NF-κB signaling

Erratum to:J Zhejiang Univ-Sci B(Biomed&Biotechnol)201920(10):816-827 https://doi.org/10.1631/jzus.B1900071The original version of this article unfortunately contained a mistake.In p.823,Figs.8 c and 8 d were incorrect,and the obvious pathological changes were mistakenly placed in the picture.