The Therapeutic Effect of Ge-Gen Decoction on a Rat Model of Primary Dysmenorrhea: Label-Free Quantitative Proteomics and Bioinformatic Analyses.

Ge-Gen decoction (GGD) is widely used for the treatment of primary dysmenorrhea (PD) in China. However, the mechanisms that underlie this effect are unclear. We investigated the protective mechanism of GGD in a rat model of PD using label-free quantitative proteomics. The model was established by the administration of estradiol benzoate and oxytocin. Thirty rats were divided into three groups (ten rats/group): a control group (normal rats), a model group (PD rats), and a treatment group (PD rats treated with GGD). The serum levels of prostaglandin E2 (PGE2) and prosn F2 (PGF2) were measured by ELISA. Nanohigh-performance liquid chromatography-tandem mass spectrometry (nano-HPLC-MS/MS) was used to identify differentially expressed proteins (DEPs), and bioinformatics was used to investigate the protein function. Proteomic data were validated by western blot analysis. Oxytocin-induced writhing responses and abnormal serum levels of PGE2 and PGF2 were reversed following the administration of GGD. A total of 379 DEPs were identified; 276 were identified between the control group and the model group, 144 were identified between the model group and the treatment group, and 41 were identified as DEPs that were common to all groups. Bioinformatics revealed that the DEPs between the control group and the model group were mainly associated with cellular component biogenesis and binding processes. The DEPs between the model group and the treatment group were mainly involved in the protein binding and metabolic process. The expression levels of HSP90AB1 and the phosphorylation levels of ERK, JNK, and P-p38 in the uteri of rats in the three groups were consistent with the proteomic findings; MAP kinases (ERK, JNK, and p38) are known to be involved in the production of inflammatory cytokines and oxytocin signaling while HSP90AB1 is known to be associated with estrogen signaling. Collectively, these data indicate that GGD may exert its protective function on PD by regulating the inflammatory response and signaling pathways associated with oxytocin and estrogen.