Analgesic and Antipyretic Activities of Ethanol Extract of Gardenia jasminoides Ellis Fruits in Mice

Abstract

This study investigates the analgesic and antipyretic effects of Gardenia jasminoides Ellis fruit in mice. In vivo  experiments were conducted using ethanol extract from Gardenia jasminoides fruit (EEGJ) at 75, 100, and 125 mg/kg.  The positive control group was treated with standard medications, including aspirin (10 mg/kg) and fentanyl (10 mL/kg)  for pain experiments, and acetaminophen (10 mg/kg) for fever experiments. In contrast, the negative control group  received normal saline (10 mL/kg). The analgesic effectiveness of EEGJ was assessed by measuring response latency and  the reduction in writhing responses. Fever was induced by injecting a 20% yeast suspension (10 mL/kg), and rectal  temperature was measured both before and after the intervention. The results demonstrated that EEGJ significantly  reduced acetic acid-induced writhing responses by 25.8%, 34.78%, and 48.27%, respectively. Furthermore, this extract exhibited a pronounced dose-dependent inhibition of formalin-induced pain during the second phase, with inhibition  rates of 15.31%, 25.23%, and 33.57%, respectively. The highest pain inhibition due to mechanical stimulus in the Haffner  tail clip test at 15 minutes was observed at a dose of 125 mg/kg, achieving an inhibition rate of 43.08%. Additionally,  after 3 hours, rectal temperature significantly decreased in the EEGJ 125 mg/kg group (37.29 ± 0.12^oC) (p < 0.05). In conclusion, our study unequivocally demonstrates that ethanol extract from Gardenia jasminoides fruit exhibits potent  analgesic and antipyretic effects, with the highest activity observed at the dose of 125 mg/kg. Phytochemical  constituents in EEGJ, such as alkaloids and flavonoids, may be responsible for the observed effects.