Novel bisdemethoxycurcumin@phytomicelle ophthalmic solution: In vitro formulation appraisal and in vivo prompting rapid corneal wound healing evaluations

A simple and novel phytochemical-based nano-ophthalmic solution was developed for the treatment of eye diseases. This nanoformulation was produced from the mixture of the phytochemicals glycyrrhizin and alpha-glycosyl hesperidin, which serve as the phytonanomaterials that solubilize bisdemethoxycurcumin (BDMC), a promising phytochemical with strong pharmacological activities but with poor water solubility. This novel nanoformulation is a clear solution named as BDMC@phytomicelle ophthalmic solution, which was formulated using a simple preparation process. The BDMC@phytomicelles were characterized by a BDMC encapsulation efficiency of 98.37% ± 2.26%, a small phytomicelle size of 4.06 ± 0.22 nm, and a small polydispersity index of 0.25 ± 0.04. With the optimization of the BDMC@phytomicelles, the apparent solubility of BDMC (i.e., the loading of BDMC in the phytomicelles) in the simulated lacrimal fluid was 3.19 ± 0.02 mg/ml. The BDMC@phytomicelle ophthalmic solution demonstrated a good storage stability. Moreover, it did not cause irritations in rabbit eyes, and it facilitated the excellent corneal permeation of BDMC in mice. The BDMC@phytomicelles demonstrated a marked effect on the in vivo induction of corneal wound healing both in healthy and denervated corneas, as seen in the induction of corneal epithelial wound healing, recovery of corneal sensitivity, and increase in corneal subbasal nerve fiber density. These strong pharmacological activities involve the inhibition of hmgb1 signaling and the induction of VIP signaling. Overall, the BDMC@phytomicelle ophthalmic solution is a novel and promising simple ocular nano-formulation of BDMC with significantly improved in vivo profiles.