Preparation of quercetin long-circulating liposomes and their therapeutic effect on diabetic peripheral neuropathy

Diabetic peripheral neuropathy (DPN) is a prevalent chronic complication of diabetes mellitus, which often results in significant patient discomfort. The objective of this study was to enhance the solubility and bioavailability of quercetin by loading quercetin into long-circulating liposomes (Q-LL) to ultimately achieve the goal of enhancing the therapeutic impact of quercetin on DPN. The Q-LL was synthesized using the film dispersion method, followed by a comprehensive series of characterizations as well as in vitro release and in vivo pharmacokinetic studies. Subsequently, the DPN rat model was established before the administration of free quercetin and Q-LL to the rats. The potential mechanism of Q-LL in the treatment of DPN was postulated by detecting levels of blood lipid, oxidative stress, and inflammation in rats after 4 weeks of oral administration. Q-LLs were successfully developed, which had a particle size of 110.93 ± 1.49 nm, a PDI of 0.179 ± 0.012, a zeta potential of − 25.37 ± 0.31 mV, an encapsulation efficiency (EE)% of 93.57 ± 0.19%, and a drug loading (DL)% of 9.66 ± 0.12%, as well as displayed a sustained release effect. This Q-LL significantly increased the solubility and in vivo circulation time of quercetin, thus significantly improving the bioavailability of quercetin. Q-LL may alleviate DPN by reducing levels of blood lipid, oxidative stress, and inflammatory response. Overall, Q-LL may offer a new strategy for the potential extension of the in vivo circulation of quercetin and enhancement of its bioavailability for DPN treatment.

Graphical abstract