Perturbations of the Proteome and of Secreted Metabolites in Primary Astrocytes from the hSOD1(G93A) ALS Mouse Model.

Roberto Stella,Maria Lina Massimino,Raphael Severino Bonadio,Stefano Cagnin,Caterina Peggion,Alessandro Bertoli

doi:10.3390/ijms22137028

Abstract

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease whose pathophysiology is largely unknown. Despite the fact that motor neuron (MN) death is recognized as the key event in ALS, astrocytes dysfunctionalities and neuroinflammation were demonstrated to accompany and probably even drive MN loss. Nevertheless, the mechanisms priming astrocyte failure and hyperactivation are still obscure. In this work, altered pathways and molecules in ALS astrocytes were unveiled by investigating the proteomic profile and the secreted metabolome of primary spinal cord astrocytes derived from transgenic ALS mouse model overexpressing the human (h)SOD1(G93A) protein in comparison with the transgenic counterpart expressing hSOD1(WT) protein. Here we show that ALS primary astrocytes are depleted of proteins—and of secreted metabolites—involved in glutathione metabolism and signaling. The observed increased activation of Nf-kB, Ebf1, and Plag1 transcription factors may account for the augmented expression of proteins involved in the proteolytic routes mediated by proteasome or endosome–lysosome systems. Moreover, hSOD1(G93A) primary astrocytes also display altered lipid metabolism. Our results provide novel insights into the altered molecular pathways that may underlie astrocyte dysfunctionalities and altered astrocyte–MN crosstalk in ALS, representing potential therapeutic targets to abrogate or slow down MN demise in disease pathogenesis.

Highlights

Introduction published maps and institutional affilAmyotrophic lateral sclerosis (ALS) is a late-onset neurodegenerative disorder characterized by the selective loss of upper and lower motor neurons (MNs) in the spinal cord, brainstem, and cerebral cortex [1,2,3,4]
The metabolomic profiles of the conditioned medium (CM) of primary cultures of spinal cord astrocytes obtained from hSOD1(WT) and hSOD1(G93A) mice (15 samples for each genotype) were acquired using UHPLC-HRMS
Important changes in the cellular derived from newborn mice of the hSOD1(G93A) ALS Tg model, which could be useful proteome and the secreted metabolome were identified in primary spinal astrocytes derived to identify disease-related mechanisms

Summary

Introduction

Amyotrophic lateral sclerosis (ALS) is a late-onset neurodegenerative disorder characterized by the selective loss of upper and lower motor neurons (MNs) in the spinal cord, brainstem, and cerebral cortex [1,2,3,4]. More than 20 genes related to fALS were identified. Among such genes, mutations in superoxide dismutase 1 (SOD1), transactive response DNA binding-43 kDa (TDP-43), fused in sarcoma/translocated in sarcoma (FUS/TLS), and the most frequent intronic hexanucleotide GGGGCC repeat expansion in the C9orf gene (accounting for the 40–50% of fALS and 7% of sALS) are responsible for approximately the 70% of all fALS monogenic cases [8,9]. Mutations in superoxide dismutase 1 (SOD1), transactive response DNA binding-43 kDa (TDP-43), fused in sarcoma/translocated in sarcoma (FUS/TLS), and the most frequent intronic hexanucleotide GGGGCC repeat expansion in the C9orf gene (accounting for the 40–50% of fALS and 7% of sALS) are responsible for approximately the 70% of all fALS monogenic cases [8,9]. iations.

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