Upregulation of 15-Hydroxyprostaglandin Dehydrogenase by Celecoxib to Reduce Pain After Laparoendoscopic Single-Site...

Background: Peritoneal stretching from CO₂ insufflation is a primary mechanism of pain associated with laparoscopy. Cyclooxygenase-2 inhibitors are promising anti-inflammatory and analgesic agents. This study aimed to evaluate the effect of celecoxib on postoperative pain reduction and associated changes in peritoneal gene expression after laparoendoscopic single-site (LESS) surgery for benign gynecologic disease. Methods: In this randomized, double-blind, placebo-controlled pilot study, 70 patients were randomly assigned to receive either celecoxib or placebo (400 mg) 40 min before surgery. Peritoneal tissues were collected before and after CO₂ insufflation. We analyzed changes in expressions of prostaglandin I₂ synthase, prostaglandin E synthase (PTGES), PTGES3, aldo-keto reductase family 1 member C1, and 15-hydroxyprostaglandin dehydrogenase (HPGD). Numeric Rating Scale (NRS) pain scores were also compared between groups. Results: A total of 62 patients completed the study: 30 in the celecoxib group and 32 in the placebo group. The mean CO₂ exposure time was 60.4 min. In a quantitative real-time polymerase chain reaction analysis, HPGD mRNA expression significantly increased after surgery in patients exposed to CO₂ for more than 60 min. Patients treated with celecoxib showed a significantly higher rate of grade 3 expression (83.3% vs. 37.5%; p = 0.01) and a level 2 increase in HPGD expression on in situ hybridization (58.3% vs. 12.5%; p = 0.01), despite no significant difference on immunohistochemistry. Moreover, celecoxib effectively reduced NRS pain scores compared to placebo. Conclusions: In this pilot study, celecoxib appeared to reduce postoperative pain and was associated with increased HPGD mRNA expression in the peritoneal tissue of patients with prolonged CO₂ exposure during LESS surgery. These exploratory findings warrant confirmation in larger trials with functional validation of HPGD expression (ClinicalTrials.gov, NCT03391570).