Sulawesi propolis induces higher apoptotic activity and lower inflammatory activity in a rat endometriosis model

BACKGROUND: Endometriosis has a major impact on women’s quality of life. The two primary pathologies are chronic inflammation and altered apoptotic activity. Sulawesi propolis has been shown to have known anti-inflammatory and pro-apoptotic properties in other diseases. OBJECTIVE: To investigate the effects of Sulawesi propolis in the rat endometriosis model. METHODS: An autologous endometriosis model was created in 60 female Wistar rats by laparotomy. Rats were divided into four groups (n = 15 in each group): control group (CG), dienogest group (DG), propolis 50 mg/kg body weight (BW)/day (P50) group, and propolis 100 mg/kg BW/day (P100) group. Each treatment group was divided into three different treatment durations (n = 5 in each treatment group): 2, 4 and 6 weeks. After treatment, laparotomy was performed to determine endometriotic tissue growth, apoptosis [caspase-3 and Bcl-2-associated X/Bcl-2 (Bax/Bcl)] and inflammation [prostaglandin-E2 (PGE2) and interleukin-1B (IL-1B)]. RESULTS: A significant difference was seen in endometriotic tissue growth between the P50 group and the CG, with the greatest reduction in the P50 6-week (P50–6) group, reaching 70.66% of the initial area. Highest Bax/Bcl-2 mRNA expression was shown in the P50–4 and P100–4 groups, highest caspase-3 expression was shown in the P50–2 and P50–4 groups, and lowest IL-1B expression was shown in the P50–4 group; all differed significantly from the CG. No significant difference in PGE2S mRNA was found between the groups. CONCLUSION: Sulawesi propolis extract suppressed endometriotic tissue growth in the rat model by increasing apoptotic activity. The effects were time-dependent, with 50 mg/kg BW as the optimal dose.