The Novel Tetra-Specific Drug C-192, Conjugated Using UniStac, Alleviates Non-Alcoholic Steatohepatitis in an MCD Diet-Induced Mouse Model.

Non-alcoholic steatohepatitis (NASH) is a complex disease resulting from chronic liver injury associated with obesity, type 2 diabetes, and inflammation. Recently, the importance of developing multi-target drugs as a strategy to address complex diseases such as NASH has been growing; however, their manufacturing processes remain time- and cost-intensive and inefficient. To overcome these limitations, we developed UniStac, a novel enzyme-mediated conjugation platform for multi-specific drug development. UniStac demonstrated high conjugation yields, optimal thermal stabilities, and robust biological activities. We designed a tetra-specific compound, C-192, targeting glucagon-like peptide 1 (GLP-1), glucagon (GCG), fibroblast growth factor 21 (FGF21), and interleukin-1 receptor antagonist (IL-1RA) simultaneously for the treatment of NASH using UniStac. The biological activity and treatment efficacy of C-192 were confirmed both in vitro and in vivo using a methionine-choline-deficient (MCD) diet-induced mouse model. C-192 exhibited profound therapeutic efficacies compared to conventional drugs, including liraglutide and dulaglutide. C-192 significantly improved alanine transaminase levels, triglyceride accumulation, and the non-alcoholic fatty liver disease activity score. In this study, we demonstrated the feasibility of UniStac in creating multi-specific drugs and confirmed the therapeutic potential of C-192, a drug that integrates multiple mechanisms into a single molecule for the treatment of NASH.

Polyoxalate nanoparticles as a biodegradable and biocompatible drug delivery vehicle.

One of major challenges in the drug delivery lies in the development of nanoparticles that are effectively delivered to targeted cells and release their payload over an extended period to achieve a clinical response. In this paper, we report a new family of biocompatible and biodegradable polymer, termed polyoxalate that degrades hydrolytically into nontoxic byproducts. Polyoxalate was synthesized from a simple one-step polymerization reaction of 1,4-cyclohexanedimethanol and oxalyl chloride and had a MW of approximately 11000 Da. This polymer was designed to degrade by water hydrolysis into 1,4-cyclohexanedimethanol and oxalic acid, which can be easily removed from a body. Polyoxalate had a hydrophobic backbone and was formulated into nanoparticles with a mean diameter of 600 nm, which is suitable for drug delivery involving phagocytosis by macrophages. Polyoxalate nanoparticles were readily taken up by RAW 264.7 macrophage cells and HEK (human embryonic kidney) 293 cells and exhibited a minimal cytotoxicity in a time- and dose-dependent manner. In comparison with PLGA nanoparticles, polyoxalate nanoparticles had a significantly higher cell viability. We anticipated that the ease of synthesis and excellent biocompatibility make polyoxalate highly potent for numerous applications in drug delivery.

Long-term Efficacy and Biocompatibility of Encapsulated Islet Transplantation With Chitosan-Coated Alginate Capsules in Mice and Canine Models of Diabetes.

BACKGROUND: Clinical application of encapsulated islet transplantation is hindered by low biocompatibility of capsules leading to pericapsular fibrosis and decreased islet viability. To improve biocompatibility, we designed a novel chitosan-coated alginate capsules and compared them to uncoated alginate capsules. METHODS: Alginate capsules were formed by crosslinking with BaCl2, then they were suspended in chitosan solution for 10 minutes at pH 4.5. Xenogeneic islet transplantation, using encapsulated porcine islets in 1,3-galactosyltransferase knockout mice, and allogeneic islet transplantation, using encapsulated canine islets in beagles, were performed without immunosuppressants. RESULTS: The chitosan-alginate capsules showed similar pore size, islet viability, and insulin secretory function compared to alginate capsules, in vitro. Xenogeneic transplantation of chitosan-alginate capsules demonstrated a trend toward superior graft survival (P = 0.07) with significantly less pericapsular fibrosis (cell adhesion score: 3.77 ± 0.41 vs 8.08 ± 0.05; P < 0.001) compared to that of alginate capsules up to 1 year after transplantation. Allogeneic transplantation of chitosan-alginate capsules normalized the blood glucose level up to 1 year with little evidence of pericapsular fibrotic overgrowth on graft explantation. CONCLUSIONS: The efficacy and biocompatibility of chitosan-alginate capsules were demonstrated in xenogeneic and allogeneic islet transplantations using small and large animal models of diabetes. This capsule might be a potential candidate applicable in the treatment of type 1 diabetes mellitus patients, and further studies in nonhuman primates are required.

Reduction of oxidative stress by p-hydroxybenzyl alcohol-containing biodegradable polyoxalate nanoparticulate antioxidant.

The large production of reactive oxygen species (ROS) leads to the oxidative stress and the subsequent functional decline of organ systems. p-Hydroxybenzyl alcohol (HBA) is known to play a pivotal protective role against oxidative stress-related diseases. We have developed biodegradable antioxidant copolyoxalate, in which HBA is chemically incorporated into its backbone for the treatment of oxidative stress-related diseases. HBA-incorporated copolyoxalate (HPOX) was designed to possess aromatic peroxalate ester linkages in its backbone and release HBA during its hydrolytic degradation. Peroxalate ester linkages in the backbone reacted with and scavenged hydrogen peroxide, leading the release of HBA in vitro. HBA released from HPOX exerted excellent antioxidant activity, such as inhibition of nitric oxide (NO) production by suppressing iNOS (inducible nitric oxide synthases) expression in lipopolysaccharide (LPS)-activated RAW 264.7 cells. HPOX nanoparticles delivered intranasally significantly reduced pulmonary inflammation and suppressed the iNOS expression. Given their excellent antioxidant and anti-inflammatory activities, we anticipate that HPOX nanoparticles are highly potent for the treatment of oxidative damage-related diseases, such as asthma.