APP antisense oligonucleotides are effective in rescuing mitochondrial phenotypes in human iPSC-derived trisomy 21 astrocytes.

INTRODUCTION

Antisense oligonucleotides (ASOs) have shown promise in reducing amyloid precursor protein (APP) levels in neurons, but their effects in astrocytes, key contributors to neurodegenerative diseases, remain unclear. This study evaluates the efficacy of APP ASOs in astrocytes derived from an individual with Down syndrome (DS), a population at high risk for Alzheimer's disease (AD).

METHODS

Human induced pluripotent stem cells (hiPSCs) from a healthy individual and an individual with DS were differentiated into astrocytes. Astrocytes were treated with APP ASOs for 10 days, and APP levels were quantified. Mitochondrial morphology and superoxide production in DS astrocytes were analyzed using super-resolution and confocal microscopy.

RESULTS

APP ASOs significantly reduced APP levels in astrocytes from both control and DS individuals. In DS astrocytes, treatment restored mitochondrial health, increasing mitochondrial number and size while reducing superoxide production.

DISCUSSION: APP ASOs effectively reduce APP levels and improve mitochondrial health in astrocytes, suggesting their potential as a therapeutic approach for DS and DS-related AD. Further in vivo studies are required to confirm these findings.

HIGHLIGHTS: APP ASOs reduce APP levels in human iPSC-derived astrocytes. APP ASO treatment rescues mitochondrial phenotypes in trisomy 21 astrocytes. This study supports ASOs as a potential therapy for Down syndrome-related Alzheimer's disease.