RESUMO
Paclitaxel (PTX) in its commercial products exhibits adverse effects owing to excipients and also has poor oral bioavailability. Present work is directed towards development of tocopheryl polyethylene glycol succinate-assisted self-nanoemulsifying system (SEDDS) for oral delivery of PTX. Box-Behnken design of experiment was employed to optimize PTX-SEDDS and was characterized for droplet size (29.76 ± 2.64 nm), zeta potential (-21.46 ± 2.52 mV), PDI (0.177 ± 0.012), drug content (4.97 ± 0.98 mg), entrapment efficiency (98.33 ± 0.54%) and in vitro drug release (51.03 ± 2.23% PTX at 72 h). PTX-SEDDS exhibited IC50; 1.58 ± 0.12 µM and a 52.46-folds higher cell uptake in MDA-MB-231 cells along with cellular and nuclear morphology changes. Significantly higher G2M cell cycle arrest, apoptosis, mitochondrial membrane potential disruption and ROS production was exhibited by PTX-SEDDS in comparison to Taxol. Up-regulation of Bax, p21, cleaved-caspase 3, -caspase 9 and down-regulation of Bcl2 and survivin suggested apoptosis via intrinsic pathways. Pharmacokinetic study showed approximately 4-folds higher oral bioavailability of PTX-SEDDS than Taxol. Significant reduction in tumour volume and weight was observed in syngeneic mammary tumour in SD rats. Tumour histopathology and TUNEL assay showed apoptosis in tumour tissue. PTX-SEDDS caused low lung metastasis, and was safe and stable. Conclusively, PTX-SEDDS could be suitable option for oral delivery of PTX.