D-079 | Unraveling the glial response after striatal dopaminergic denervation through single nuclei RNA sequencing

Disorders of the Nervous System
Author: Melina Paula Bordone | Email: melina_bordone@yahoo.com

Melina Bordone^1°, Claudio Schuster^2°, Chang Li^3°,  Yogita Sharma^3°, Jenny Johansson^3°, Anna Hammarberg^3°, Marcelo Marti^2°,  Angela Cenci^3°, Juan Ferrario

^1° Instituto de Biociencias, Biotecnología y Biología Traslacional (iB3), Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina.
^2° IQUIBICEN, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina.
^3° Department Experimental Medical, Science, Wallenberg Neuroscience Center, Lund University, Sweden

The striatum is a complex brain region essential for motor function that is mainly affected by dopaminergic denervation in Parkinson’s disease (PD). The aim was to perform single nuclei RNA sequencing from striata of intact and hemiparkinsonian mice at early and chronic stages of dopaminergic denervation to obtain cell-type specific transcriptional profiles. For this, unilateral 6-OHDA lesions in the mid forebrain bundle were used to model PD. Striata were immediately dissected at 5 or 28 days post lesion (DPL) for nuclei isolation. cDNA libraries were prepared and sequenced from 8500 FACS-sorted nuclei from 4 samples/group using a droplet-based RNA sequencing technology (10X Genomics). Data were first preprocessed to generate high quality expression matrices for each sample, and then integrated into a single one containing 46955 nuclei that were clustered and annotated based on the expression of well-established mRNA markers. Using DESeq2 we perform a pseudobulk analysis to obtain differentially expressed genes for each cluster and treatment comparison. A massive transcriptional response was observed at 5DPL in dSPNs, iSPNs, microglia, astrocytes, OPCs and oligodendrocytes. Notably, while in glial cells it ceased at 28DPL, in neurons it progressed specially in dSPNs. This is the first transcriptomic study at single cell level on the time course of a 6-OHDA lesion addressing the contributions of different striatal cell types, with special focus on glial cells.