Preparation, characterization, and pharmacological investigation of withaferin-A loaded nanosponges for cancer therapy; in vitro, in vivo and molecular docking studies

Abstract

The rapidly growing global burden of cancer poses a major challenge to public health and demands a robust approach to access promising anticancer therapeutics. In parallel, nanotechnology approaches with various pharmacological properties offer efficacious clinical outcomes. The use of new artificial variants of nanosponges (NS) as a transporter of chemotherapeutic drugs to target cells has emerged as a very promising tool. Therefore, in this research, ethylcellulose (EC) NS were prepared using the ultrasonication assisted-emulsion solvent evaporation technique. Withaferin-A (WFA), an active ingredient in Withania somnifera, has been implanted into the nanospongic framework with enhanced anticancer properties. Inside the polymeric structure, WFA was efficiently entrapped (85 ± 11%). The drug (WFA) was found to be stable within polymeric nanosponges, as demonstrated by Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) studies. The WFA-NS had a diameter of 117 ± 4 nm and zeta potential of −39.02 ± 5.71 mV with a polydispersity index (PDI) of 0.419 ± 0.073. In addition, scanning electron microscopy (SEM) revealed the porous surface texture of WFA-NS. In vitro anticancer activity (SRB assay) results showed that WFA–NS exhibited almost twice the anticancer efficacy against MCF-7 cells (IC50 = 1.57 ± 0.091 µM), as quantified by flow cytometry and comet tests. Moreover, fluorescence microscopy with DAPI staining and analysis of DNA fragmentation revealed apoptosis as a mechanism of cancer cell death. The anticancer activity of WFA-NS was further determined in vivo and results were compared to cisplatin. The anticancer activity of WFA-NS was further investigated in vivo, and the data were consistent to those obtained with cisplatin. At Day 10, WFA-NS (10 mg/kg) significantly reduced tumour volume to 72 ± 6%, which was comparable to cisplatin (10 mg/kg), which reduced tumour volume to 78 ± 8%. Finally, the outcomes of molecular modeling (in silico) also suggested that WFA established a stable connection with nanosponges, generating persistent hydrophobic contacts (polar and nonpolar) and helping with the attractive delayed-release features of the formulation. Collectively, all the findings support the use of WFA in nanosponges as a prototype for cancer treatment, and opened up new avenues for increasing the efficacy of natural product-derived medications.