Effect of Bushen Huatan Prescription on Serum LPS and TLR4/MyD88/NF-κB Signaling Pathway in Rats with Ovariectomy-induced Osteoporosis / 中国实验方剂学杂志

ABSTRACT

Objective:To explore the effect of Bushen Huatan prescription on serum lipopolysaccharide （LPS） and Toll-like receptor 4 （TLR4）/ myeloid cell differentiation protein 88 （MyD88）/nuclear transcription factor-<italic>κ</italic>B （NF-<italic>κ</italic>B） signaling pathway in rats with ovariectomy-induced osteoporosis. Method:Sixty SPF 6-month-old female rats were randomly divided into sham operation group， model group， estradiol valerate group and Bushen Huatan prescription low， medium and high dose groups.One week after modeling by bilateral ovariectomy， 8 rats in each group were selected to receive intragastric administration.The estradiol valerate group was given 0.184 mg·kg^-1 by gavage， and Bushen Huatan prescription low， middle and high dose groups were given 4.7， 9.4 and 18.8 g·kg^-1 by gavage， sham operation group and model group were given 0.9% saline 4 mL by gavage respectively.After 12 weeks of intervention， the rats were sacrificed for detection.Serum LPS was detected by enzyme linked immunosorbent assay （ELISA）， while protein expressions of TLR4， MyD88 and phosphorylated （p）-NF-<italic>κ</italic>B p65 in bone tissue were detected by Western blot， and the mRNA expressions of TLR4， MyD88， NF-<italic>κ</italic>B p65， IL-1<italic>β</italic>， and IL-6 in bone tissue were detected by quantitative real-time polymerase chain reaction（PCR）. Result:Compared with sham operation group， the serum LPS level as well as protein expression of TLR4， MyD88， p-NF-<italic>κ</italic>B p65 and mRNA expression of TLR4， MyD88， NF-<italic>κ</italic>B p65， IL-1<italic>β</italic>， and IL-6 significantly increased in model group（<italic>P</italic><0.05）.Compared with the model group， serum LPS level， protein expression of TLR4， MyD88， and p-NF-<italic>κ</italic>B p65， mRNA levels of TLR4， MyD88， and NF-<italic>κ</italic>B p65 in bone tissues as well as downstream inflammatory factors IL-1<italic>β</italic>， IL-6 mRNA expression decreased to different degrees in estradiol valerate group and Bushen Huatan prescription high dose group（<italic>P</italic><0.05）. Conclusion:Bushen Huatan prescription can reduce serum LPS content， regulate mRNA and protein expression of TLR4， MyD88， NF-<italic>κ</italic>B p65 and p-NF-<italic>κ</italic>B p65 in TLR4/MyD88/NF-<italic>κ</italic>B pathway， and down-regulate mRNA levels of IL-1<italic>β</italic> and IL-6 in bone tissues to improve bone microstructure and inhibit the development of postmenopausal osteoporosis （PMOP）.