Chrysin ameliorates pain through regulation of the serum metabolomics in the rats

Chrysin is a natural flavonoid that exhibits various pharmacological activities including pain relief. However, the effects of chrysin on changes of metabolic profiles during pain remain unclear. The aim of this study was to analyze the biomarkers related to pain in serum and to evaluate the analgesic properties of chrysin in a rat model of pain.

Male Wister rats were divided into four groups (n = 5). Pain was induced by injecting 50 μL of formalin into the hind paw. Chrysin and diclofenac (10 mg/kg, intraperitoneal injection) was administered to the intact and pain groups. All injections were given 30 minutes before pain induction. Immediately, the behavioral test was performed. Then the serum sample was separated for ¹HNMR-based metabolite analysis.

Chrysin treatment alleviated the paw licking events, flinching response, and pain score. The integrated analyses further revealed three major metabolic changes including glycine-serine-threonine, taurine-hypotaurine, and arginine by comparing the serums from intact operated rats, pain rats, and pain rats treated with chrysin, and suggested that chrysin may improve pain by regulating the biosynthesis of these metabolic pathways.

These findings provide insights into metabolic pathways involved in pain and the analgesic effects of chrysin and may help to identify potential targets for the anti-pain properties of chrysin.