Gum-based nanocapsules comprising naphthoquinones enhance the apoptotic and trypanocidal activity against Trypanosoma evansi

Nanoencapsulation is a promising approach to enhance the therapeutic potential of a drug. Herein, three selected naphthoquinone (NTQ) derivatives, based on the IC50 value against Trypanosoma evansi, were encapsulated using gum damar as biocompatible and biodegradable natural gum via nanoprecipitation method. Nanoformulation of NTQs (NNTQs) was less than 150 nm in size, was found to be stable and released the drug in a sustained manner. All the three NNTQs exhibited significant antitrypanosomal effect and morphological changes at approximately two to three times lesser drug concentrations. The nanoformulations exhibited enhanced production of reactive oxygen species (ROS) in the axenic culture of T. evansi and less cytotoxic effect on horse peripheral blood mononuclear cells relative to pure NTQs. As evidenced by flow cytometry, the NNTQs showed dose-dependent and time-dependent increased transition of live cells (AV -PI-) to early apoptotic cells (AV+PI-), late apoptotic cells (AV -PI+), and necrotic cells (AV+PI+) using annexin V/propidium iodide probe analysis. The results concluded that NNTQs induced more ROS, apoptosis and necrotic effects that exhibited more inhibitory effect on the growth of T. evansi with respect to respective NTQ by themselves.

Automated summary

Nanoencapsulation using natural gum damar as the encapsulation material has shown potential for enhancing the therapeutic effects of drugs. In this study, naphthoquinone derivatives were successfully encapsulated, and the nanoformulations exhibited significant antitrypanosomal effects with minimal cytotoxicity. The nanoparticles were stable, released the drug in a sustained manner, and induced reactive oxygen species production and apoptotic and necrotic effects on the Trypanosoma evansi cells.