Fibrinolytic and Anti-Abdominal Adhesion Effects of Tannin Derivatives from Rumex nepalensis Spreng.: Activity-Guided Isolation and Evaluation in a Postoperative Rat Model

Abdominal adhesions following surgical procedures are a significant cause of postoperative complications, including chronic pain, infertility, and intestinal obstruction. Preventing adhesion formation remains a critical focus of preclinical and clinical research. In this study, we evaluated the fibrinolytic and antiadhesive potential of extracts from four plant species: Asphodeline lutea (L.) Rchb., Rheum ribes L., Rubia tinctorum L., and Rumex nepalensis Spreng. Among these, R. nepalensis exhibited the highest fibrinolytic activity in vitro, and bioactivity-guided fractionation led to the isolation of two major compounds, cinnamtannin B1 (RN2) and epicatechin gallate (RN3). In vitro assays demonstrated that RN2 displayed stronger fibrinolytic activity than RN3. The most active extracts, fractions and compound were further evaluated in a rat model of surgically induced intra-abdominal adhesions. A subfraction containing both compounds significantly reduced adhesion formation. These findings indicate that the bioactive constituents of R. nepalensis, and potentially the other studied species, may contribute to developing novel antiadhesive therapies. Overall, the study highlights the therapeutic potential of plant-derived flavonoids, anthraquinones, and tannins in adhesion prevention and supports further preclinical investigations to optimize dosage, formulation, and delivery methods. These results provide a foundation for translating natural compounds into practical strategies to reduce postoperative adhesion-related complications.