Evaluation of the Tumor Reduction Potentials of Pleurolobus gangeticus Using In Vitro and In Vivo Models

The plant parts of Pleurolobus gangeticus (L.) J.St.-Hil. (synonym: Desmodium gangeticum), Fabaceae, were extracted and evaluated for its antitumor potential using in vitro and in vivo lymphoma models. Cytotoxic potentials and apoptosis induction was evaluated using in vitro systems. Ethanol extract, among others, had the lowest IC50 value of 17.5 mu g/ml in cytotoxicity assay conducted in DLA (Dalton lymphoma ascites) cells. Cytotoxicity assays performed on YAC-1 cells showed reduction in the number of live cells from 10 x 10(4) to 2.2 x 10(4) after 48 h of treatment with ethanol extract (15 mu g/ml) at which time point the untreated cells multiplied to reach 17.5 x 10(4) in number. The flow cytometric analysis revealed that at this concentration, 44.7% cells are already in the early apoptotic phase by 24 h of treatment. Considering its bioactivity, ethanol extract was further used for in vivo toxicology profiling and antitumor studies in mice models. Treatment with nontoxic doses of ethanol extract (200 and 400 mg/kg b.w.) significantly reduced the tumor burden in mice. The biopsy analysis of tumor tissue of ethanol extract treated animals also showed a considerable number of apoptotic and necrotic cells. Ethanol extract was also subjected to chromatographic analysis (GC-MS and LC-MS), which revealed presence of several pharmacologically important molecules, but the absence of salicin was also noticeable. This highlights the role of other compounds detected in giving the extract its tumor reduction property. Further investigation to identify the active components and to obtain a deeper knowledge on their mechanism of action is worthwhile to acquire novel safer and effective anticancer drugs.

Automated summary

This study evaluated the antitumor potential of Pleurolobus gangeticus plant parts and found that ethanol extract demonstrated significant cytotoxicity and apoptosis induction in vitro and in vivo models. Ethanol extract also reduced tumor burden in mice models and showed the presence of pharmacologically important molecules.