NLRP3 inflammasome as a key molecular target underlying cognitive resilience in amyotrophic lateral sclerosis

Up to 50% of amyotrophic lateral sclerosis patients present with cognitive deficits in addition to motor dysfunction, but the molecular mechanisms underlying diverse clinical and pathological presentations remain poorly understood. There is therefore an unmet need to identify molecular drivers of cognitive dysfunction to enable better therapeutic targeting and prognostication. To address this, we employed a non-biased approach to identify molecular targets using a deeply phenotyped, clinically stratified cohort of cognitively affected and unaffected brain regions from three brain regions of 13 amyotrophic lateral sclerosis patients with the same cognitive screening test performed during life. Using NanoString molecular barcoding as a sensitive mRNA sequencing technique on post-mortem tissue, we profiled a data-driven panel of 770 genes using the Neuropathology Panel, followed by region and cell type-specific validation using BaseScope in situ hybridisation and immunohistochemistry. We identified 50 significantly dysregulated genes that are distinct between cognitively affected and unaffected brain regions. Using BaseScope in situ hybridisation, we also demonstrate that macromolecular complex regulation, notably NLRP3 inflammasome modulation, is a potential, therapeutically targetable, pathological correlate of cognitive resilience in ALS. © 2021 The Authors. The Journal of Pathology published by John Wiley & Sons, Ltd on behalf of The Pathological Society of Great Britain and Ireland.

[Radiation of parotid glands for salivary flow reduction in amyotrophic lateral sclerosis]

Radiation of the parotid and submandibular glands was performed in 18 patients with pronounced hypersalivation at a late stage of amyotrophic lateral sclerosis (ALS). Single bilateral radiation of the parotid and posterior submandibular glands was made in the dosage of 7.0-7.5 Gy. Salivation volume was measured before and after the radiation therapy. Sixteen patients exhibited satisfactory and marked salivary flow reduction during 4-6 months. Xerostomia developed in 1 patient who needed assignment of artificial salivary substitute and 1 patient did not respond to the therapy. The patient's caregivers reported a positive effect in all the cases. Tolerance of the therapy was good except rare side effects. Radiation of the parotid glands significantly reduced salivary flow in ALS, especially in patients receiving an adequate amount of water.

Trial of immunosuppression in amyotrophic lateral sclerosis using total lymphoid irradiation

Although the cause of amyotrophic lateral sclerosis (ALS) remains unknown, recent studies have suggested an autoimmune mechanism of pathogenesis. Previous trials of immunosuppressive treatment have yielded inconclusive results. Our study was designed to determine whether more powerful and prolonged immunosuppression, produced by total lymphoid irradiation (TLI), would alter the course of ALS. In a double-blind, randomized, placebo-controlled study, 30 patients with classic ALS were treated with TLI, and 31 were given sham radiation. Quantitative measurements of muscle strength, functional motor activity, and humoral and cellular immune status were followed for 2 years, or until death or respirator dependence. Motor function in the TLI-treated and control groups showed no significant differences throughout the study. Overall survival was not significantly different in the TLI-treated and control groups. TLI effectively suppressed cellular and humoral immune function throughout the 2-year study period. Analysis of the relationship between immunosuppression and motor functions showed no consistent effect of treatment. We conclude that powerful and prolonged immunosuppression produced by TLI did not benefit patients with ALS. This fails to support the concept of an autoimmune mechanism of pathogenesis of ALS.