Exploring the anti-inflammatory potential of purified Plumbago zeylanica L. root extracts: an integrated in silico , in vitro , and in vivo approach

The utilization of purified roots from Plumbago zeylanica in traditional Ayurvedic medicine for addressing various inflammatory conditions such as arthritis prompted this study to explore the in vitro anti-inflammatory potential of distinct extracts derived from these roots. Additionally, the study assessed the anti-inflammatory and analgesic activities of the most potent extract in Wistar rats (either sex) and predicted the bioactive phytoconstituents through in silico molecular docking with the cyclooxygenase-II enzyme. The purification of the plant material involved the traditional detoxification process of shodhana. The purified roots underwent hot continuous extraction (Soxhlet extraction) to produce extracts with increasing polarity. The in vitro anti-inflammatory activity of these extracts, at varying concentrations, was evaluated through assays measuring the inhibition of albumin denaturation and hypotonicity-induced hemolysis. Analgesic activity and anti-inflammatory activities were assessed in rats through formalin-induced pain and carrageenan-induced paw edema models, respectively. Prediction of bioactive compounds was conducted through molecular docking and dynamics of different phytoconstituents of the purified roots of P. zeylanica with the cyclooxygenase-II (COX-2) enzyme. In vitro studies demonstrated the anti-inflammatory effects in different extracts, methanolic extract being the most potent. In vivo studies revealed analgesic and anti-inflammatory activities in the methanolic extract. Molecular docking results indicated good interaction between phytoconstituents of the methanolic extract and COX-2 enzyme, with chitranone being the most inhibiting compound having stable ligand anchoring. The study concludes that the methanolic extract of purified roots of P. zeylanica possesses notable anti-inflammatory and analgesic activities, potentially attributed to the presence of its COX-2 inhibitor compounds.