AMYOTROPHIC LATERAL SCLEROSIS: RAPIDLY ACCELERATING COMPLEX NEURO-DEGENERATIVE DISEASE

An amyotrophic lateral sclerosis is a group of progressive neurodegenerative disorders of motor neurons that leads to weakness, muscle atrophy, progressive paralysis, and respiratory insufficiency with a life anticipation of only three years after the onset of disease symptoms. It impairs the functions of both upper and lower motor neurons. The specific mechanism for the disease remains largely unidentified. At present, there is no specific treatment to cure or reverse the progression of the disease. ALS is generally diagnosed based upon the medical history and signs and symptoms; however, it is quite difficult to diagnose the disease in its initial stages. Several studies indicate that various predominant disease mechanisms such as oxidative stress, excitotoxicity, mitochondria dysfunction, aberrant protein homeostasis, defective RNA processing, formation of cytoplasmic inclusion, endoplasmic reticulum stress, endosomal dynamic dysfunctions, protein aggregation, neuroinflammation, oligodendrocyte degeneration, and microglial activation are involved in the pathophysiology of ALS. The various gene mutations (c9orf72, TARDBP, SOD1, and FUS) are also associated with disease mechanisms, so ALS is a complex genetic disorder involving multiple combinations of genes in amalgamation with environmental exposures. Through targeting the above-said disease, mechanisms is likely to contribute to the development of novel therapeutic treatments for the patients suffering from ALS. The review papers present the overview of key disease mechanisms and associated gene mutations involved in the pathophysiology of ALS, its clinical features, and several brain regions involved in the disease.