Objective:To investigate the possible mechanism of Zaogong Erteng decoction (ZGETD) in the treatment of endometritis.Methods:Femal mice were injected 2.5 mg/mL lipopolysaccharide into uterine horn to induce endometritis model. After modelling, low-dose ZGETD, high-dose ZGETD or amoxicillin was given once a day for 7 d. The appearance of the uterus and pathological changes of uterine tissue were observed 7 d later, and the uterine index was calculated. The expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 in mouse uterine tissue was detected by enzyme-linked immunosorbent assay. The activity of myeloperoxidase (MPO) in mouse uterine tissue was measured by redox reaction. The active ingredients of ZGETD and the target and signal pathway of treatment of endometritis were analyzed by network pharmacology. Western blotting and qRT-PCR were used to detect the expressions of Toll-like receptor 4 (TLR4), P65, p-P65, interferon regulatory factor 3 (IRF3) and p-IRF3 proteins and chemokines CXCL5 and CXCL8 in the mouse uterus, respectively. Terminal dUTP nick end labeling detected endometrial cell apoptosis and endometrial thickness was measured. After treatment, the female rats were mated with the male rats, and the mating rate, the pregnancy rate and the number of implantation sits in the injected uterine horn on day 8 of gestation were counted. Results:Both ZGETD and amoxicillin have atherapeutic effect on endometritis, but compared with low-dose ZGETD and amoxicillin, high-dose ZGETD can significantly alleviate the edema and congestion of uterine tissue and reduce the uterine index (all P=0.001). After treatment, the uterine cavity epithelium of mice was smooth and complete, the uterine gland structure was normal, and no bleeding area and inflammatory cell aggregation were observed. Compared with amoxicillin, high-dose ZGETD significantly decreased the expression of inflammatory factors (TNF-α, IL-1β and IL-6) and MPO activity (all P<0.001). The expression of chemokines ( CXCL5 and CXCL8) was significantly reduced (all P<0.05). The signaling pathways TLR4, nuclear factor kappa-B (NF-κB) and TNF related to the treatment of endometritis by ZGETD were screened by network pharmacology, and their action targets (TLR4, NF-κB and IRF3) were verified. Quercetin, fisetin and luteolin were found to be the most active ingredients acting on these targets. High-dose ZGETD significantly inhibited the activation of TLR4/NF-κB and TLR4/IRF3 pathways ( P<0.05), decreased endometrial cell apoptosis ( P<0.05), and increased endometrial thickness ( P<0.001), mating rate ( P<0.001), pregnancy rate ( P<0.001) and implantation site number of uterine horn on the injection side of LPS after treatment ( P=0.001). Conclusion:High-dose ZGETD has a significant therapeutic effect on endometritis, which may be closely related to the down-regulation of TLR4 signaling pathway.

Objective:To investigate the possible mechanism of Zaogong Erteng decoction (ZGETD) in the treatment of endometritis.Methods:Femal mice were injected 2.5 mg/mL lipopolysaccharide into uterine horn to induce endometritis model. After modelling, low-dose ZGETD, high-dose ZGETD or amoxicillin was given once a day for 7 d. The appearance of the uterus and pathological changes of uterine tissue were observed 7 d later, and the uterine index was calculated. The expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 in mouse uterine tissue was detected by enzyme-linked immunosorbent assay. The activity of myeloperoxidase (MPO) in mouse uterine tissue was measured by redox reaction. The active ingredients of ZGETD and the target and signal pathway of treatment of endometritis were analyzed by network pharmacology. Western blotting and qRT-PCR were used to detect the expressions of Toll-like receptor 4 (TLR4), P65, p-P65, interferon regulatory factor 3 (IRF3) and p-IRF3 proteins and chemokines CXCL5 and CXCL8 in the mouse uterus, respectively. Terminal dUTP nick end labeling detected endometrial cell apoptosis and endometrial thickness was measured. After treatment, the female rats were mated with the male rats, and the mating rate, the pregnancy rate and the number of implantation sits in the injected uterine horn on day 8 of gestation were counted. Results:Both ZGETD and amoxicillin have atherapeutic effect on endometritis, but compared with low-dose ZGETD and amoxicillin, high-dose ZGETD can significantly alleviate the edema and congestion of uterine tissue and reduce the uterine index (all P=0.001). After treatment, the uterine cavity epithelium of mice was smooth and complete, the uterine gland structure was normal, and no bleeding area and inflammatory cell aggregation were observed. Compared with amoxicillin, high-dose ZGETD significantly decreased the expression of inflammatory factors (TNF-α, IL-1β and IL-6) and MPO activity (all P<0.001). The expression of chemokines ( CXCL5 and CXCL8) was significantly reduced (all P<0.05). The signaling pathways TLR4, nuclear factor kappa-B (NF-κB) and TNF related to the treatment of endometritis by ZGETD were screened by network pharmacology, and their action targets (TLR4, NF-κB and IRF3) were verified. Quercetin, fisetin and luteolin were found to be the most active ingredients acting on these targets. High-dose ZGETD significantly inhibited the activation of TLR4/NF-κB and TLR4/IRF3 pathways ( P<0.05), decreased endometrial cell apoptosis ( P<0.05), and increased endometrial thickness ( P<0.001), mating rate ( P<0.001), pregnancy rate ( P<0.001) and implantation site number of uterine horn on the injection side of LPS after treatment ( P=0.001). Conclusion:High-dose ZGETD has a significant therapeutic effect on endometritis, which may be closely related to the down-regulation of TLR4 signaling pathway.