A kidney protection nanoparticle based on Alpinia oxyphylla fructus polysaccharide by modulating macrophage polarization.

The use of natural polysaccharides from traditional Chinese medicine as carrier materials has great potentiality in drug delivery. Nootkatone (NKT) demonstrated good pharmacological activity in treating kidney injury, but its solubility and bioavailability are not very good which may affect the effectiveness of its therapeutic effect. Alpinia oxyphylla fructus polysaccharide (AOP), as a plant polysaccharide, has multiple pharmacological activities and may help to provide synergy for NKT. Therefore, AOP nanoparticles loaded with NKT (AOP-NKT NPs) were prepared for the prevention of acute kidney injury in this study. The sizes of AOP-NKT NPs are 291.60 ± 3.73 nm, and the Zeta potential values are 35.2 ± 0.65 mV. The nanoparticles exhibited excellent stability in pH, NaCl solution, temperature, and storage. The nanoparticles also improved the solubility and oral bioavailability of NKT. In biocompatibility experiments, AOP-NKT NPs showed lower macrophage toxicity than NKT, and the nanoparticles had good blood compatibility and in vivo biosafety. In vivo, prophylactic administration of this nanoparticle could enhance the ability of NKT in promoting macrophage M2 polarization, reducing renal inflammation and thus improve renal function and repair renal damage. In conclusion, the present study may provide the possibility for AOP as a nano delivery vehicle for renal injury protective drugs.