O uso da celulas-tronco para o tratamento do alzheimer

Abstract

Alzheimer's disease is a progressive and, so far, irreversible neurodegenerative disease that primarily affects memory and other cognitive functions. It was first described by neurologist Alois Alzheimer, in 1907. Currently, about 1.2 million people are living with some form of dementia, and 100,000 new cases are reported each year. The disease is characterized by three main stages, and its pathophysiology involves the formation of senile plaques and neurofibrillary tangles in the brain, leading to cortical atrophy and neuronal death, mainly affecting areas responsible for cognitive and motor functions. Alzheimer's is marked by the presence of β-amyloid and phosphorylated Tau proteins. Currently, treatment is mainly symptomatic and unable to prevent the progression of the disease. Available medications are targeted at improving cholinergic function and include acetylcholinesterase inhibitors such as donepezil, rivastigmine, galantamine, and metrifonate. However, they cause many side effects such as nausea, vomiting, and diarrhea, leading patients and their families to discontinue treatment. Stem cells (SCs) have the potential to regenerate brain tissue damaged by Alzheimer's and replace lost neuronal cells. They are precursor cells with the ability to self-renew and differentiate into various cell types. There are embryonic SCs found in embryos and adult SCs found in adult tissues, and based on their differentiation capacity, they are classified as totipotent, pluripotent, or multipotent. Research conducted in the last 5 years using animal models that addressed different types of SCs has shown positive results in treatment. It has been observed that transplanted SCs have the ability to differentiate into neuronal cells and replace damaged cells, as well as release growth factors and anti-inflammatory molecules that can promote neuronal survival.