Design and development of a soluble PDA-Emodin-PVP-MN patch and its anti-obesity effect in rats

Abstract

Emodin has been proven to have weight-reducing and lipid-lowering effects. In order to make emodin play a better anti-obesity role, we designed and developed an emodin loaded dissolving microneedle patch, in which emodin existed in the form of emodin-polyvinylpyrrolidone co-precipitate (Emodin-PVP).Meanwhile, polydopamine (PDA) was added to the microneedle patch (PDA-Emodin-PVP-MN) for photothermal-enhanced chemotherapy of obesity. The drug loading of PDA-Emodin-PVP-MN was 0.37 ± 0.025 mg per patch, and the cumulative release of the microneedle patch was up to 96.25% under NIR irradiation (808 nm, 0.6 W/cm 2 ). The microneedle patch with NIR radiation signi cantly reduced body weight, waist circumference, lipid-body ratio and serum free fatty acids of the obese model rats, and the volume of adipocytes of fat droplets was signi cantly reduced after the treatment with microneedle patch under NIR radiation. No obvious toxicity was observed in hemolytic test and microscopic histopathological analysis. The mechanism of action of the weight-reducing might be ascribed to the expression level of hormone-sensitive lipase (HSL) and lipoprotein lipase (LPL) involved in fat metabolism.