Synergistic mechanism of stir-baked curcumae radix with vinegar in dysmenorrhea rats based on UPLC-Q-TOF/MS metabolomics

Curcumae Radix (i.e. Huangsiyujin: HSYJ), a well-known traditional Chinese medicine (TCM), has been widely used in clinical practice for many years to treat depression and primary dysmenorrhea. Modern pharmacological researches have demonstrated its anti-inflammatory, antidepressant, and dysmenorrhea relief effects. According to the processing theory of TCM, it is believed that stir-baked HSYJ with vinegar may enhance the ability to disperse stagnant hepatoqi and alleviate pain. However, whether the vinegar concoction of HSYJ can enhance the therapeutic effect on the Qi stagnation due to liver depression (LDQS) type of dysmenorrhea and what its mechanism has not been well explained. Based on the processing drugs theory of "stir-baked with vinegar into liver", a metabolomic approach was used to investigate the therapeutic effect and mechanism of stir-baked HSYJ with vinegar to enhance the treatment of dysmenorrhea in rats. By establishing a rat model of dysmenorrhea of the "LDQS" type, observation of hemorheology, uterine pathological sections, COX-2 and OTR protein expression and other indicators; analysis of urinary metabolic changes in rats by UPLC-Q-TOF-MS technique, to compare the differential biomarkers and metabolic pathways in the treatment of dysmenorrhea due to "liver stagnation and qi stagnation" before and after stir-baked HSYJ with vinegar. Stir-baked HSYJ with vinegar significantly inhibited the writhing response of rats, improved hemorheology, repaired damaged diseased uterus and inhibited high expression of COX-2 and OTR proteins in uterus; 68 differential metabolites were screened from the urine of rats, compared with the raw HSYJ, the levels of 14 metabolites were significantly changed in stir-baked HSYJ with vinegar, involving the pathways of phenylalanine, tyrosine and tryptophan metabolism, cysteine and methionine metabolism, aspartate and glutamate metabolism. The potentiating effect of stir-baked HSYJ with vinegar may be related to the regulation of multiple amino acid metabolic pathways.