Intracerebellar upregulation of Rheb(S16H) ameliorates motor dysfunction in mice with SCA2.

Acta Pharmacol Sin

School of Life Science and Biotechnology, BK21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu, 41566, Republic of Korea.

Published: July 2025


Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

Cerebellar ataxia (CA) is characterized by impaired balance and coordination due to the loss of cerebellar neurons caused by various factors, and effective treatments are currently lacking. Recently, we observed reduced expression of signaling molecules in the mammalian target of rapamycin complex 1 (mTORC1) pathway in the cerebellum of mice with spinocerebellar ataxia type 2 (SCA2) compared with wild-type mice. To investigate the effects of mTORC1 upregulation on motor dysfunction in mice with SCA2, we administered an intracerebellar injection of adeno-associated virus serotype 1 carrying a constitutively active form of Ras homolog enriched in brain [Rheb(S16H)], which is an upstream activator of mTORC1. This treatment led to increased Rheb(S16H) expression in calbindin-D28K-positive Purkinje cells and increased levels of neurotrophic factors. Additionally, Rheb(S16H) upregulation reduced abnormal behaviors and protected Purkinje cells in mice with SCA2. Our findings suggest that upregulating Rheb(S16H) in the cerebellum may be a promising therapeutic strategy for hereditary CA.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC12205046PMC
http://dx.doi.org/10.1038/s41401-025-01504-yDOI Listing

Publication Analysis

Top Keywords

mice sca2
12
motor dysfunction
8
dysfunction mice
8
purkinje cells
8
mice
5
intracerebellar upregulation
4
rhebs16h
4
upregulation rhebs16h
4
rhebs16h ameliorates
4
ameliorates motor
4

Similar Publications

Amyotrophic lateral sclerosis (ALS) involves motor neuron death due to mislocalized TDP-43. Pathologic TDP-43 associates with stress granules (SGs), and lowering the SG-associated protein ataxin-2 (ATXN2) using Atxn2-targeting antisense oligonucleotides prolongs survival in TAR4/4 sporadic ALS mice but failed in clinical trials likely due to poor target engagement. Here we show that an AAV with potent motor neuron transduction delivering Atxn2-targeting miRNAs reduces Atxn2 throughout the central nervous system at doses 40x lower than published work.

View Article and Find Full Text PDF

Establishment of a humanized SCA2 mouse model carrying a CAA disruption preventing CAG repeat expansion in pathogenic genes.

Animal Model Exp Med

June 2025

School of Pharmaceutical Sciences, Yunnan Key Laboratory of Pharmacology for Natural Products, Kunming Medical University, Kunming, China.

Background: Spinocerebellar ataxia type 2 (SCA2) is a neurodegenerative disease marked by significant clinical and genetic heterogeneity, primarily caused by expanded CAG mutations in the ATXN2 gene. The unstable expansion of CAG repeats disrupts the genetic stability of animal models, which is detrimental to disease research.

Methods: In this study, we established a mouse model in which CAG repeats do not undergo microsatellite instability (MSI) across generations.

View Article and Find Full Text PDF

ATXN2L primarily interacts with NUFIP2, the absence of ATXN2L results in NUFIP2 depletion, and the ATXN2-polyQ expansion triggers NUFIP2 accumulation.

Neurobiol Dis

June 2025

Goethe University Frankfurt, University Hospital, Clinic of Neurology, Experimental Neurology, Heinrich- Hoffmann-Str. 7, 60528 Frankfurt am Main, Germany; Institute for Clinical Neuroanatomy, Dr. Senckenberg Anatomy, Fachbereich Medizin, Goethe University Frankfurt, Frankfurt am Main, Germany. Elec

The cytoplasmic Ataxin-2 (ATXN2) protein associates with TDP-43 in stress granules (SG) where RNA quality control occurs. Mutations in this pathway underlie Spinocerebellar Ataxia type 2 (SCA2) and Amyotrophic Lateral Sclerosis. In contrast, Ataxin-2-like (ATXN2L) is predominantly perinuclear, more abundant, and essential for embryonic life.

View Article and Find Full Text PDF

Intracerebellar upregulation of Rheb(S16H) ameliorates motor dysfunction in mice with SCA2.

Acta Pharmacol Sin

July 2025

School of Life Science and Biotechnology, BK21 FOUR KNU Creative BioResearch Group, Kyungpook National University, Daegu, 41566, Republic of Korea.

Cerebellar ataxia (CA) is characterized by impaired balance and coordination due to the loss of cerebellar neurons caused by various factors, and effective treatments are currently lacking. Recently, we observed reduced expression of signaling molecules in the mammalian target of rapamycin complex 1 (mTORC1) pathway in the cerebellum of mice with spinocerebellar ataxia type 2 (SCA2) compared with wild-type mice. To investigate the effects of mTORC1 upregulation on motor dysfunction in mice with SCA2, we administered an intracerebellar injection of adeno-associated virus serotype 1 carrying a constitutively active form of Ras homolog enriched in brain [Rheb(S16H)], which is an upstream activator of mTORC1.

View Article and Find Full Text PDF

Staufen2 dysregulation in neurodegenerative disease.

J Biol Chem

March 2025

Department of Neurology, University of Utah, Salt Lake City, Utah, USA. Electronic address:

Staufen2 (STAU2) is an RNA-binding protein that controls mRNA trafficking and expression. Previously, we showed that its paralog, Staufen1 (STAU1), was overabundant in cellular and mouse models of neurodegenerative diseases and amyotrophic lateral sclerosis (ALS) patient spinal cord. Here, we investigated features of STAU2 that might parallel STAU1.

View Article and Find Full Text PDF