Andrographolide nanoparticles in leishmaniasis: characterization and in vitro evaluations

Area of Science:

• Pharmacology
• Nanotechnology
• Parasitology

Background:

• Andrographolide (AG) shows potent antileishmanial activity but faces bioavailability and delivery challenges.
• Current chemotherapy for leishmaniasis is limited by AG's poor plasma half-life and tissue distribution.
• Nanoparticulation offers a strategy to overcome these limitations for AG delivery.

Purpose of the Study:

• To develop and characterize andrographolide nanoparticles (AGnp) for enhanced antileishmanial chemotherapy.
• To evaluate the efficacy of AGnp in targeting monocyte-macrophage cells infected with Leishmania parasites.
• To optimize AGnp formulation using polyvinyl alcohol (PVA) as a stabilizer.

Main Methods:

• AG nanoparticles (AGnp) were formulated using poly(DL-lactide-co-glycolic acid).
• Particle size and zeta potential were determined using photon correlation spectroscopy.
• Nanoparticle morphology was assessed via atomic force microscopy.
• Antileishmanial activity was evaluated in vitro, comparing AGnp to pure AG.

Main Results:

• Optimized AGnp exhibited an average particle size of 173 nm and a zeta potential of -34.8 mV.
• Atomic force microscopy confirmed spherical nanoparticles with a smooth surface.
• AGnp with 4% PVA demonstrated significantly enhanced antileishmanial activity (IC₅₀ 34 μM) compared to pure AG (IC₅₀ 160 μM).

Conclusions:

• AGnp effectively targets Leishmania-infected monocyte-macrophage cells.
• Nanoparticulation significantly improves the therapeutic potential of andrographolide for leishmaniasis treatment.
• AGnp represent a promising approach for the chemotherapy of neglected tropical diseases like leishmaniasis.