Project description:Huntington’s disease (HD) is a monogenetic neurodegenerative disorder caused by the expansion of a polyglutamine (polyQ) stretch in huntingtin (htt). Here we show that mutant htt reduces the transcription of insulin-like growth factor 1 (IGF-1) and leads to loss of IGF-1 in HD brains, HD mouse models and mutant htt-transgenic microglial cells. IGF-1 replacement therapy by transplantation of genetically engineered mouse neuronal precursor cells (mNPCs) in a mouse model of HD reverted the motor phenotype and countered striatal neuronal loss.
Project description:Using Huntington’s disease (HD) mouse models that quantitatively replicate the reduction of striatal Phoshodiesterase 10 (PDE10) levels in manifest Huntington’s disease patients, we demonstrate the potential therapeutic benefit of PDE10 inhibition on correcting basal ganglia circuitry deficits thought to drive disease symptomology in patients. PDE10 inhibition acutely restored corticostriatal input and boosted cortically driven indirect pathway activity in HD models with compromised PDE10 levels. We show that cyclic nucleotide signaling processes are impaired in the models, and that elevation of both the cAMP and cGMP nucleotides afforded by PDE10 inhibition are required for this rescue. Global phosphoproteomic profiling of striatal proteins in response to PDE10 inhibition provide novel information on the plausible neural substrates responsible for the improvement. Finally, we show that long-term chronic treatment of the Q175 knock-in mouse model with PDE10A inhibitors, starting at a presymptomatic age, showed improvements, above and beyond those seen during acute administration, including a partial reversal of striatal deregulated transcripts predominantly driven through activation of the AP-1 and CREB transcription factor complexes, and a prevention of the emergence of some cardinal HD neurophysiological deficits.
Project description:To evaluate the effect of CYP46A1 treatment in R6/2 mice, we performed gene expression profiling analysis using data obtained from RNA-seq of 6 different conditions
Project description:AAV gene therapy has recently been approved for clinical use and shown to be efficacious and safe in a growing number of clinical trials. However, the safety of AAV as a gene therapy has been challenged by a few studies that documented hepatocellular carcinoma (HCC) after AAV gene delivery in mice. The association between AAV and HCC has been difficult to reconcile and is the subject of intense debate because numerous AAV studies have not reported toxicity. Here, we report a comprehensive study of HCC in a large number of mice following therapeutic AAV gene delivery. Using a sensitive high-throughput integration site-capture technique and global expressional analysis, we found that AAV integration into the Rian locus and the over-expression of a proximal gene, Rtl1, were associated with HCC. In addition, we identify a number of genes with differential expression that maybe useful in the study, diagnosis and treatment of HCC. We demonstrate that AAV vector dose, enhancer-promoter selection, and the timing of gene delivery are the defining factors in AAV-mediated insertional mutagenesis. Our results help explain the AAV-mediated genotoxicity previously observed and have important implications for the design of both safer AAV vectors and gene therapy studies. To investigate the possibility that insertional mutagenesis by AAV contributed to the development of HCC, we collected normal and tumor tissues from adult mouse livers that received AAV injection at a neonatal stage.
Project description:AAV gene therapy has recently been approved for clinical use and shown to be efficacious and safe in a growing number of clinical trials. However, the safety of AAV as a gene therapy has been challenged by a few studies that documented hepatocellular carcinoma (HCC) after AAV gene delivery in mice. The association between AAV and HCC has been difficult to reconcile and is the subject of intense debate because numerous AAV studies have not reported toxicity. Here, we report a comprehensive study of HCC in a large number of mice following therapeutic AAV gene delivery. Using a sensitive high-throughput integration site-capture technique and global expressional analysis, we found that AAV integration into the Rian locus and the over-expression of a proximal gene, Rtl1, were associated with HCC. In addition, we identify a number of genes with differential expression that maybe useful in the study, diagnosis and treatment of HCC. We demonstrate that AAV vector dose, enhancer-promoter selection, and the timing of gene delivery are the defining factors in AAV-mediated insertional mutagenesis. Our results help explain the AAV-mediated genotoxicity previously observed and have important implications for the design of both safer AAV vectors and gene therapy studies. To investigate the possibility that insertional mutagenesis by AAV contributed to the development of HCC, we collected normal and tumor tissues from adult mouse livers that received AAV injection at a neonatal stage.
Project description:AAV gene therapy has recently been approved for clinical use and shown to be efficacious and safe in a growing number of clinical trials. However, the safety of AAV as a gene therapy has been challenged by a few studies that documented hepatocellular carcinoma (HCC) after AAV gene delivery in mice. The association between AAV and HCC has been difficult to reconcile and is the subject of intense debate because numerous AAV studies have not reported toxicity. Here, we report a comprehensive study of HCC in a large number of mice following therapeutic AAV gene delivery. Using a sensitive high-throughput integration site-capture technique and global expressional analysis, we found that AAV integration into the Rian locus and the over-expression of a proximal gene, Rtl1, were associated with HCC. In addition, we identify a number of genes with differential expression that maybe useful in the study, diagnosis and treatment of HCC. We demonstrate that AAV vector dose, enhancer-promoter selection, and the timing of gene delivery are the defining factors in AAV-mediated insertional mutagenesis. Our results help explain the AAV-mediated genotoxicity previously observed and have important implications for the design of both safer AAV vectors and gene therapy studies.