Is Innate Immunity and Inflammasomes Involved in Pathogenesis of Amyotrophic Lateral Sclerosis (ALS)?

Abstract

Amyotrophic Lateral Sclerosis (ALS) or Lou Gehrig's disease is an axonopathy with adultonset, progressive and irreversible degeneration of upper and lower motor neurons. Around 90% of ALS is considered as sporadic ALS (sALS) without apparent genetic cause while in the familial type of ALS (fALS) at least one affected blood relative needs to be identified. Both sALS and fALS show similar progression and pathological profile. Biochemical and immunological roles have been reported for both types of ALS. It has been suggested that mutation in SOD1 gene would be responsible for the oxidative stress and neurotoxicity. Besides, oxidative stress, protein aggregation, altered cholinergic synapse, neuro-inflammation and production of pro-inflammatory cytokines have also been reported. Thus, the focus of the present review was on biochemical and immunological biomarkers and pathogenic mechanism. Regulatory T cells, pro-inflammatory cytokines and activation of pro-inflammatory signaling pathway are discussed. The activation of NRL inflammasomes in ALS and the involvement of IL-18, IL-1β and caspases-1 are also suggested. The presence and importance of HMGB-1 (DAMP) and activation of Tolllike receptors and/or RAGE also are envisaged. The patents US20140212508, WO2014145776, WO2014145118, US20140255371, US20140194427, US20140243400, WO2014128254, WO2014076702, WO2014071449, WO2014043696, WO2014001742, and WO2013082299 are summarized. This review intends to evaluate the biochemical and immunological responses and the involvement of inflammasomes in the pathogenesis of ALS. In the present review, we suggest hypothetical model for ALS pathogenesis and we discuss some patents that suggest new treatment and/or therapeutic targets. Due to a large number of patents covering therapy and control of neurodegenerative diseases, our focus was restricted only to discuss the latest registered patents in 2014.