Rationale: Hedgehog (Hh) pathway plays an essential role in
liver fibrosis by promoting the proliferation of hepatic stellate cells (HSCs) by enhancing their metabolism via yes-associated
protein 1 (YAP1). Despite the presence of several inhibitors, Hh signaling cannot be controlled exclusively due to their poor efficacy and the lack of a suitable delivery system to the injury site. Therefore, it is rationale to develop new potent Hh inhibitors and suitable delivery carriers. Methods: Based on the structure and activity of Hh inhibitor
GDC-0449, we replaced its
sulfonamide group with two methylpyridine-2yl at
amide nitrogen to synthesize
MDB5. We compared the Hh pathway inhibition and anti-fibrotic effect of
MDB5 with
GDC-0449 in vitro. Next, we developed
MDB5 loaded
micelles using our methoxy poly(
ethylene glycol)-blockpoly(2-methyl-2-carboxyl-
propylene carbonate-graft-
dodecanol (PEG-PCC-
g-DC) copolymer and characterized for physicochemical properties. We evaluated the therapeutic efficacy of
MDB5 loaded
micelles in common bile duct
ligation (CBDL) induced
liver fibrosis, mouse model. We also determined the intrahepatic distribution of fluorescently labeled
micelles after
MDB5 treatment. Results: Our results show that
MDB5 was more potent in inhibiting Hh pathway components and HSC proliferation in vitro. We successfully developed
MDB5 loaded
micelles with particle size of 40 ± 10 nm and
drug loading up to 10% w/w.
MDB5 loaded
micelles at the dose of 10 mg/kg were well tolerated by mice, without visible sign of toxicity. The serum
enzyme activities elevated by CBDL was significantly decreased by
MDB5 loaded
micelles compared to
GDC-0449 loaded
micelles.
MDB5 loaded
micelles further decreased
collagen deposition, HSC activation, and Hh activity and its target genes in the liver.
MDB5 loaded
micelles also prevented liver sinusoidal endothelial capillarization (LSEC) and therefore restored perfusion between blood and liver cells. Conclusions: Our study provides evidence that
MDB5 was more potent in inhibiting Hh pathway in HSC-T6 cells and showed better hepatoprotection in CBDL mice compared to
GDC-0449.