Health services utilization prior to amyotrophic lateral sclerosis diagnosis: A province-wide study of individuals treated with riluzole in Ontario, Canada

Sex-Specific Markers of Neuroinflammation and Neurodegeneration in the Spinal Cord Proteome of the SOD1G93A Mouse Model of Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder that has no cure. The underlying mechanistic details of sex differences in the ALS spinal cord, the site of disease onset, are not understood to an extent that could guide novel drug development. To address this, the spinal cords of 120-day-old wild-type (WT) and SOD1G93A (familial mouse model of ALS with mutant superoxide dismutase 1) mice were subjected to untargeted, quantitative proteomics using tandem mass tag acquisition on high-resolution mass spectrometric instrumentation. Compared to WT, both male and female SOD1G93A spinal cords exhibited an upregulation of neuroinflammatory cascades of both peripheral and central origins, as well as a downregulation of proteins reflective of death and dysfunction of cells within the spinal cord. However, female and male SOD1G93A mouse spinal cords exhibited sex-specific differences in proteins compared to respective WT that related to immune response, as well as cellular structure, function, and homeostasis. The proteomic datasets presented provide entire cohort and sex-specific spinal cord drug targets and disease biomarkers in the SOD1G93A mouse model of ALS that may guide future drug development and sex selection in preclinical study designs utilizing the SOD1G93A model.

Sex biology in amyotrophic lateral sclerosis

Although sex differences in amyotrophic lateral sclerosis (ALS) have not been studied systematically, numerous clinical and preclinical studies have shown sex to be influential in disease prognosis. Moreover, with the development of advanced imaging tools, the difference between male and female brain in structure and function and their response to neurodegeneration are more definitive. As discussed in this review, ALS patients exhibit a sex bias pertaining to the features of the disease, and their clinical, pathological, (and pathophysiological) phenotypes. Several epidemiological studies have indicated that this sex disparity stems from various aetiologies, including sex-specific brain structure and neural functioning, genetic predisposition, age, gonadal hormones, susceptibility to traumatic brain injury (TBI)/head trauma and lifestyle factors.