# Effects of Modified Messenger RNA of Adiponectin Delivered by Lipid Nanoparticles on Adipogenesis and Bone Metabolism In Vitro and In Vivo

## TL;DR

This study shows that delivering modified adiponectin mRNA via lipid nanoparticles can reduce fat formation and promote bone healing in obese mice.

## Contribution

The novel contribution is demonstrating the use of lipid nanoparticle-delivered APN mRNA to modulate adipogenesis and bone metabolism in vitro and in vivo.

## Key findings

- APN-LNP inhibited adipogenesis in 3T3-L1 cells and enhanced osteogenic gene expression in MC3T3-E1 cells.
- APN-LNP reduced matrix metalloproteinase 9 in RANKL-stimulated RAW264.7 cells, indicating anti-resorptive effects.
- In vivo, APN-LNP promoted bone healing in diet-induced obese mice and reduced fasting blood glucose and body weight.

## Abstract

Adiponectin (APN) is a secreted adipokine that plays a key role in modulating energy and bone metabolism, as well as regulating inflammatory responses. The overexpression of APN has been proposed as a potential therapeutic strategy for treating obesity and related disorders. Lipid nanoparticles (LNPs) are promising vectors for transporting messenger ribonucleic acid (mRNA) molecules. This study tested whether delivering a stabilized version of adiponectin mRNA (APN mRNA) using lipid nanoparticles could reduce fat formation and promote bone repair in vitro and in vivo. We demonstrated that transfection with APN-LNP upregulated the mRNA and protein expression of APN, while inhibiting adipogenesis in 3T3-L1 adipocytes. APN-LNP enhanced osteogenic gene expression in MC3T3-E1 cells in a dose-dependent manner. It also reduced matrix metalloproteinase 9 expression in receptor activator of nuclear factor-kappaB ligand (RANKL)-stimulated RAW264.7 cells, suggesting an anti-resorptive effect. In vivo, a femoral fracture model was established to explore the application of APN-LNP in promoting bone healing in diet-induced obese mice. Micro-computed tomography and histology analysis indicated that intravenous injection with APN-LNP promoted bone healing. Fasting blood glucose and body weight were decreased in the APN-LNP group. Moreover, APN-LNP increased bone sialoprotein and runt-related transcription factor 2 expression in contralateral femurs, as well as interleukin-10 expression in white adipose tissues. Thus, our study provides promising preclinical data on the potential use of APN-LNP for treating bone disorders in obesity.