MicroRNA-26b protects against MASH development and can be efficiently targeted with lipid nanoparticles

Background & Aims

The prevalence of metabolic dysfunction-associated steatohepatitis (MASH) is increasing, urging more research into the underlying mechanisms. MicroRNA-26b (miR-26b) might play a role in several MASH-related pathways. Therefore, we aimed to determine the role of miR-26b in MASH and its therapeutic potential using miR-26b mimic-loaded lipid nanoparticles (LNPs).

Methods

Apoe^-/-Mir26b^-/-,Apoe^-/-LysM^creMir26b^fl/flmice, and respective controls were fed a western-type diet to induce MASH. Plasma and liver samples were characterized regarding lipid metabolism, hepatic inflammation, and fibrosis. Additionally, miR-26b mimic-loaded LNPs were injected inApoe^-/-Mir26b^-/-mice to rescue the phenotype and key results were validated in human precision-cut liver slices. Finally, kinase profiling was used to elucidate underlying mechanisms.

Results

Apoe^-/-Mir26b^-/-mice showed increased hepatic lipid levels, coinciding with increased expression of scavenger receptor a and platelet glycoprotein 4. Similar effects were found in mice lacking myeloid-specificmiR-26b. Additionally, hepatic TNF and IL-6 levels and amount of infiltrated macrophages were increased inApoe^-/-Mir26b^-/-mice. Moreover,Tgfbexpression was increased by themiR-26bdeficiency, leading to more hepatic fibrosis. A murine treatment model with miR-26b mimic-loaded LNPs reduced hepatic lipids, rescuing the observed phenotype. Kinase profiling identified increased inflammatory signaling uponmiR-26bdeficiency, which was rescued by LNP treatment. Finally, miR-26b mimic-loaded LNPs also reduced inflammation in human precision-cut liver slices.

Conclusions

Overall, our study demonstrates that the detrimental effects ofmiR-26bdeficiency in MASH can be rescued by LNP treatment. This novel discovery leads to more insight into MASH development, opening doors to potential new treatment options using LNP technology.

Graphical abstract