Puberulin

Puberulin is a coumarin compound and an orally effective analgesic. It is found in Choisya ternata var. Sundance. Puberulin exhibits analgesic activity in mouse models against chemical and thermal pain inducers, and this activity does not involve opioid or muscarinic receptors. Puberulin can be utilized in the study of neuropathic pain.

Puberulin, in concentrations of 25-300 μg/mL, demonstrates an excellent linear relationship in HPLC quantitative analysis, with a regression coefficient exceeding 0.99. This colorless crystalline solid was successfully isolated from the ethanol extract of Choisya ternata var. Sundance using countercurrent chromatography, and its purity was confirmed by HPLC.

Administered orally in single doses ranging from 0.3 to 10 mg/kg, Puberulin shows dose-dependent analgesic effects in male Swiss Webster mice with formalin-induced neurogenic pain, achieving a maximum reduction in paw licking duration of 68% at 10 mg/kg. At 0.3 mg/kg and 1 mg/kg doses, Puberulin also exhibits analgesic activity against glutamate-induced pain but is ineffective at 10 mg/kg. However, Puberulin at 10 mg/kg does not alleviate capsaicin-induced pain. It demonstrates central analgesic effects by significantly increasing the hot plate pain threshold at 0.3 mg/kg, 1 mg/kg, and 10 mg/kg. At a 1 mg/kg dose, Puberulin's central analgesic activity is not mediated by opioid receptors, as naloxone does not inhibit its effect, nor is it mediated by muscarinic receptors, as atropine cannot suppress its effect.