Novel self-nanomicellizing solid dispersion based on rebaudioside A: a potential nanoplatform for oral delivery of curcumin

Abstract

PurposeRebaudioside A (RA) has nanocarrier characteristics that allow it to self-assemble into micelles in aqueous solutions. The purpose of this study was to determine if a self-nanomicellizing solid dispersion based on RA could be utilized as an oral nano-drug delivery system.Materials and methodsCurcumin (Cur) served as a model hydrophobic drug, and a Cur-loaded self-nanomicellizing solid dispersion based on RA (RA-Cur) was formulated. The properties of RA-Cur in the solid state and in aqueous solution were characterized. The antioxidant activity and mechanism of RA-Cur endocytosis were also investigated. The pharmacokinetics, biodistribution in the intestinal tract, and anti-inflammation properties were also evaluated in vivo.ResultsRA-Cur could be easily fabricated, and it self-assembled into ultrasmall micelles (particle size ~4 nm) in a homogeneous distribution state (polydispersity index <0.2) when dissolved in water. Cur was readily encapsulated into RA micelles and this improved its water solubility (to 14.34±1.66 mg/mL), as well as its in vitro release and membrane permeability. The antioxidant activities of Cur in RA-Cur were also significantly improved. Biodistribution in the intestinal tract confirmed a significant enhancement of Cur absorption in the duodenum, jejunum, and ileum by encapsulation in RA-Cur, and the absorption of RA-Cur was governed by mixed transcytosis mechanisms. Pharmacokinetic tests of RA-Cur in rats revealed a dramatic 19.06-fold enhancement of oral bioavailability when compared to free Cur. More importantly, oral administration of RA-Cur could efficiently ameliorate ulcerative colitis in a mouse model induced by dextran sodium sulfate.ConclusionSelf-nanomicellizing solid dispersions based on RA have great potential as novel oral nano-drug delivery systems for hydrophobic drugs such as Cur.

Mechanisms of increased bioavailability through amorphous solid dispersions: a review

“…A study performed on curcumin as a model drug and rebaudioside A as carrier showed that ultra-small micelles (approximately 4 nm) are formed after dissolution of the solid system (Hou et al, 2019). Authors found indications for transcytosis of these particles in the everted intestinal ring model.…”

Antiviral effect of phytochemicals from medicinal plants: Applications and drug delivery strategies

“…Zhang et al [94] aimed to improve the oral absorption of baicalin, which has low solubility and poor permeability, by using a micellar formulation comprised of the carriers Pluronic P123 copolymer and sodium taurocholate. Sustained release profile of baicalin-loaded mixed micelles, in in vitro drug release experiment, held in several pH conditions, showed 14% drug released after 2 h in gastric conditions and 54% release within 48 h in intestinal conditions, compared to 34% and 79% release [105], nanoparticles [106][107][108][109][110], phytosome [111], nanoliposome [112], mixed micelles [113,114], SNEDDS [115,116], nanocarrier [117,118], nanoemulsion [119], nanosuspension [ Mixed micelles [129,130], nanoparticles [131,132], solid dispersion [133,134] , SNEDDS [135] , SMEDDS [136], lipid carrier [137], copolymeric micelles [138], exosomes [139] Naringenin DENV, HCV SNEDDS [140], solid dispersion [141], nanoparticles [142,143] , liposome [144], nanosuspension [145,146] In vitro uptake studies, carried out with a caco-2 cell line, determined the absorption of baicalin within the mixed micelles and verified their internalization ability. Baicalin-loaded ST-P123-MMs formulation achieved high oral bioavailability (Fig.…”

Obstacles against the Marketing of Curcumin as a Drug

“…Data shown in Table 8 summarize some of formulations and their pharmacokinetic properties. In order to increase curcumin bioavailability, different pharmaceutical strategies, including combination with adjuvant substances such as piperine, encapsulation, formulation in nanoparticles, liposome, micelles, nanomicellizing solid dispersion etc., have been proposed, shedding new light to overcome this pivotal limitation [214][215][216][217].…”