Protein expression profiling of rat uteruses with primary dysmenorrhea syndrome.

Purpose: The aim of this study was to investigate differentially expressed proteins (DEPs) and their functions in the uteruses of primary dysmenorrhea (PD) rats using label-free quantitative proteomics analysis. Methods: The PD rat model was induced by injecting both estradiol benzoate and oxytocin. Twenty rats were equally divided into two groups: a control group (normal rats), a PD model group (PD rats). Writhing scores and serum levels of Prostaglandin E2 (PGE2) and Prostaglandin F2α (PGF2α) were used to evaluate the success of the rat PD model. The DEPs were identified and analyzed by label-free quantitative proteomics and bioinformatics analyses. Results: A total of 276 DEPs were identified, including 119 up-regulated DEPs and 157 down-regulated DEPs. Bioinformatics revealed that the DEPs were mainly associated with 'protein binding', 'metabolism', 'signal conduction' and 'focal adhesion'. The proteomic findings were verified by western blot analysis, which confirmed that myosin light-chain kinase (MLCK), heat shock protein 90 AB1 (HSP90AB1), apolipoprotein A1 (Apoa1), p38 MAP kinase, c-Jun N-terminal kinase (JNK), and extracellular signal-related kinase 1/2 (ERK1/2) were significantly differentially expressed in the control and PD samples. Conclusions: These results provide a deeper understanding of the molecular pathogenesis of PD. The DEPs found in the present study may provide new ideas for further study of the mechanism of PD and aid the search for biomarkers for early diagnosis and treatment. [ABSTRACT FROM AUTHOR]