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.

Managing excessive saliva with salivary gland irradiation in patients with amyotrophic lateral sclerosis.

OBJECTIVE: A significant fraction of patients with amyotrophic lateral sclerosis (ALS) are unable to swallow saliva, which may result in the spillage of saliva outside of the oral cavity. Although anticholinergic agents and botulin toxin injections are considered the first line of treatment, they have not been effective for all patients. We performed a literature search on therapeutic salivary gland irradiation in patients with ALS. METHODS: We searched the PubMed for English language publications up to December 2014 on therapeutic salivary gland irradiation in patients with ALS. The search was performed using the following key words: amyotrophic lateral sclerosis, excessive salivation, sialorrhea, and radiation therapy. RESULTS: The majority of ALS patients with excessive salivation respond well to salivary gland irradiation. The whole bilateral submandibular, and whole or partial bilateral parotid glands have been the target tissue for radiation therapy in most of the published studies. Various radiation therapy regimens have been utilized. The response to radiation therapy lasts for several months. CONCLUSIONS: The majority of ALS patients with excessive salivation respond well to salivary gland irradiation. Neurologists should consider this treatment option for select patients with ALS and excessive salivation.

Unilateral parotid electron beam radiotherapy as palliative treatment for sialorrhea in amyotrophic lateral sclerosis.

When ALS patients experience oropharyngeal weakness, sialorrhea can become a considerable challenge. Drooling has a profound negative impact in patient's quality of life causing embarrassing social situations. Several therapeutic modalities, including anticholinergic drugs, botulinum toxin injection, and radiotherapy have emerged as treatments for drooling in ALS. This retrospective case series study examined the effect of palliative radiotherapy in controlling problematic oral secretions in 10 ALS patients refractory to medical management. External electron beam radiation was targeted to a single parotid gland unilaterally with a total dose of 1500 cGy in 3 fractions at a depth determined by CT scanning. One patient received additional radiotherapy to the contralateral parotid due to persistent secretions. All patients reported improvement with a reduction in the intensity and amount of drooling. In 5 of 10 patients, anticholinergics were discontinued and were reduced in another two. There were no major side effects of treatment. We conclude that unilateral parotid electron radiotherapy provides satisfactory relief from sialorrhea in ALS patients and should be considered as a therapeutic option for patients who are refractory to medical management.

Light therapy and supplementary Riboflavin in the SOD1 transgenic mouse model of familial amyotrophic lateral sclerosis (FALS).

BACKGROUND AND OBJECTIVE: Familial amyotrophic lateral sclerosis (FALS) is a neurodegenerative disease characterized by progressive loss of motor neurons and death. Mitochondrial dysfunction and oxidative stress play an important role in motor neuron loss in ALS. Light therapy (LT) has biomodulatory effects on mitochondria. Riboflavin improves energy efficiency in mitochondria and reduces oxidative injury. The purpose of this study was to examine the synergistic effect of LT and riboflavin on the survival of motor neurons in a mouse model of FALS. STUDY DESIGN/MATERIALS AND METHODS: G93A SOD1 transgenic mice were divided into four groups: Control, Riboflavin, Light, and Riboflavin+Light (combination). Mice were treated from 51 days of age until death. A single set of LT parameters was used: 810 nm diode laser, 140-mW output power, 1.4 cm(2) spot area, 120 seconds treatment duration, and 12 J/cm(2) energy density. Behavioral tests and weight monitoring were done weekly. At end stage of the disease, mice were euthanized, survival data was collected and immunohistochemistry and motor neuron counts were performed. RESULTS: There was no difference in survival between groups. Motor function was not significantly improved with the exception of the rotarod test which showed significant improvement in the Light group in the early stage of the disease. Immunohistochemical expression of the astrocyte marker, glial fibrilary acidic protein, was significantly reduced in the cervical and lumbar enlargements of the spinal cord as a result of LT. There was no difference in the number of motor neurons in the anterior horn of the lumbar enlargement between groups. CONCLUSIONS: The lack of significant improvement in survival and motor performance indicates study interventions were ineffective in altering disease progression in the G93A SOD1 mice. Our findings have potential implications for the conceptual use of light to treat other neurodegenerative diseases that have been linked to mitochondrial dysfunction.

[Radiation of parotid glands for salivary flow reduction in amyotrophic lateral sclerosis]. / Naruzhnoe obluchenie okoloushnykh zhelez dlia umen'sheniia sliunotecheniia pri bokovom amiotroficheskom skleroze.

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.