Mechanism of Bushen Zhuyun Prescription on Improving Luteal Function of Brown Norway Rats Based on MAPKs Signaling Pathway / 中国实验方剂学杂志

ABSTRACT

ObjectiveTo investigate the possible mechanism of Bushen Zhuyun prescription （BSZYP） to reduce the level of ovarian apoptosis in Brown Norway （BN） rats with luteal phase deficiency （LPD）. MethodFifty SPF female BN rats were randomly divided into a model group， a dydrogesterone group （0.002 g·kg-1）， and a low （4.5 g·kg-1）， a medium （9 g·kg-1）， and a high-dose （18 g·kg-1） BSZYP groups， with ten rats in each group. The rats were administrated with corresponding drugs by gavage， once a day for three estrus cycle. Western blot was used to detected the protein expression levels of c-Jun NH2 terminal kinase （JNK）， extracellular signal-regulated kinase （ERK）， phosphorylated-ERK （p-ERK）， phosphorylated-JNK （p-JNK）， p38 mitogen-activated protein kinase （p38 MAPK）， phosphorylated-p38 MAPK （p-p38 MAPK ）， B-cell lymphoma （Bcl-2）， and Bcl-2 associated X protein （Bax） in ovary. Real-time quantitative polymerase chain reaction （Real-time PCR） was used to detect the mRNA expression levels of ERK， JNK， p38 MAPK， Bax， and Bcl-2 in ovary. Enzyme-linked immunosorbent assay （ELISA） was used to detect the serum progesterone （P） and estradiol （E2） levels. Hematoxylin-eosin （HE） staining was used to observe the ovarian tissue morphology. ResultCompared with the model group， the recovery of estrus cycle of rats in all BSZYP groups had statistical significance after 1-circle administration （P<0.05）. The ovarian tissue morphology in the low-dose BSZYP group was improved， and that in the medium and high-dose BSZYP groups was significantly improved with clear follicle， less vesicular follicle and atretic follicle， and more granular layers. The number of luteum， especially the fresh luteum， in the medium and high-dose groups was increased with smooth edge and large volume. The mRNA expression level of Bcl-2 was increased in all-dose BSZYP groups， while the mRNA expression level of Bax was significantly decreased in all-dose BSZYP group （P<0.05， P<0.01）. The mRNA expression levels of JNK and p38 MAPK were significantly decreased in the high-dose BSZYP group （P<0.01）， and the mRNA expression levels of ERK were increased in the low and medium-dose BSZYP groups （P<0.05）. The protein expression level of Bcl-2 was significantly increased in the medium and high-dose BSZYP groups （P<0.01）， and the protein expression level of Bax was significantly decreased in the all-dose BSZYP groups （P<0.01）. No significant difference was observed in the protein expressions of JNK， ERK， and p38 MAPK in the BSZYP groups. The protein expression levels of p-ERK in the ovarian tissues of rats were significantly inoreased in the medium and high-dose BSZYP group （P<0.01）， p-JNK， and p-p38 MAPK in the ovarian tissues of rats were significantly decreased in the medium and high-dose BSZYP group （P<0.01）. The level of E2 was increased in all-dose BSZYP groups （P<0.05， P<0.01）， and the level of P in the medium-dose BSZYP group was increased （P<0.05）. ConclusionBSZYP improved the serum sex hormones， restored the estrous cycle， reduced atretic follicle and vesiculation， and maintained luteal morphology and function of BN rats， so as to improve luteal function and treat luteal phase deficiency. The mechanism of BSZYP may be related to reduce the level of ovarian tissue apoptosis in BN rats by regulating MAPKs signaling pathway.