Naringenin Cocrystals Prepared by Solution Crystallization Method for Improving Bioavailability and Anti-hyperlipidemia Effects.

Naringenin exerts anti-inflammatory, hypolipidemic, and hepatoprotective effects; however, it shows low oral bioavailability because of poor water solubility. In this work, cocrystals of naringenin were formed to address these issues. Using the solution crystallization method, various naringenin cocrystals were prepared with different cocrystal coformers, including naringenin-nicotinamide, naringenin-isonicotinamide, naringenin-caffeine, naringenin-betaine, and naringenin-L-proline. The formation of these cocrystals was assayed by using DSC, XRD, and FT-IR spectroscopy. The stoichiometric ratio of naringenin and the CCFs in the corresponding cocrystals was investigated by NMR. The solubility of naringenin, as well as its dissolution rate, was markedly improved by forming cocrystals. The oral bioavailability of naringenin administered as naringenin-L-proline and naringenin-betaine cocrystals was achieved significantly greater than that of pure naringenin (p < 0.05). In particular, the C_max of naringenin-L-proline and naringenin-betaine cocrystals were 2.00-fold and 3.35-fold higher, and the AUC of naringenin-L-proline and naringenin-betaine cocrystals were 2.39-fold and 4.91-fold, respectively, higher than pure naringenin in rats. With the naringenin-betaine cocrystals for oral delivery, the drug distribution in the liver was significantly increased compared to pure naringenin. Accordingly, the naringenin-betaine cocrystals showed improved anti-hyperlipidemia effects on the C57 BL/6J PNPLA3 I148M transgenic mouse hyperlipidemia model. Collectively, cocrystal formation is a promising way to increase the bioavailability of naringenin for treating hyperlipidemia.