Berberine attenuates hyperalgesia in mice with adenomyosis

Purpose Adenomyosis is a common gynecological disease, but its pathogenesis and treatment options are not yet completely clear. This study aimed to investigate the analgesic effect of berberine on tamoxifen-induced neonatal mouse adenomyosis and its curative effects on the disease. Methods The mouse adenomyosis model was established in neonatal female mice via oral administration of tamoxifen suspended solution. Adenomyosis mice were given berberine by intraperitoneal injection with the dosage of 5, 10, and 20 mg/kg body weight, respectively, at 17 weeks after birth. The pain sensation of the mice was evaluated by hotplate and tail-flick tests. The mRNA levels of gene expression were detected by RT-qPCR. The protein expression was analyzed by ELISA and Western blot. Results Berberine reduced the uterine weight, suppressed the myometrial infiltration of ectopic endometrium, improved the hotplate and tail-flick latency of the adenomyosis mice. Mechanistically, berberine downregulated the expression of genes related to pain and inflammation, such as TRPV1, COX-2, VEGF and OTR, impaired the inflammatory response at the DRG site, and inhibited the expression of TLR4 in DRG and uterine tissues. Conclusions Berberine attenuates hyperalgesia and exhibits analgesic and therapeutic effects on adenomyosis mice.