O uso da fitoterapia na doença de alzheimer: um estudo de correlação dos extratos das folhas do caryocar coriaceum.: análise fitoquímica, atividade antioxidante e toxicidade

Abstract

Dementia of the Alzheimer type is recognized, like other dementias, as an important public health problem worldwide. In Brazil, of the more than 29 million people over 60 years of age, nearly 2 million have dementias, and around 40 to 60% of them are of the AD type. Herbal medicine can play a promising role in the treatment of AD, requiring the development of research to provide data to support its use in clinical practice. The therapeutic importance of pequi trees has been studied and scientific experiments confirm its effectiveness. In part of the North and Northeast regions of Brazil, the species Caryocar coriaceum (C. coriaceum) is found, which plays a fundamental socioeconomic role in these regions. In view of this, this work proposed a two-phase methodology. The first phase aimed to determine the phytochemical profile, evaluate the antioxidant potential and cytotoxicity of C. coriaceum leaf extracts. The leaf extracts were obtained using two methodologies: i) 70% ethanol in a Soxhlet apparatus, originating the crude hydroethanol extract (EBH); ii) sequential extraction, starting with degreasing, followed by extraction with methanol and 70% ethanol, originating the sequential extracts methanol (ESM) and ethanol (ESE). Phytochemical screening detected the presence of flavonoids, tannins, phytosterols/triterpenoids, quinones and saponins. Total phenolic content was determined with major contents in EBH (422.55 ± 28.23 mg EAG/g), total flavonoids with higher content in ESM (82.39 ± 2.05 mg ER/g) and antioxidant potential by the DPPH method which revealed that the EBH (17.97 ± 2.49 A µg/ml) and ESM (16.99 ± 0.66 µg/ml) are equivalent to the rutin standard (IC50= 15.85 ± 0.08 µg/ml ). In the chemical characterization by HPLC, gallic acid, catechin, syringic acid, chlorogenic acid, p-coumaric acid, naringin, vitexin, rutin and isoharmetin were identified. The toxicity, analyzed by the Allium cepa method, revealed that, with the exception of ESM, the other extracts present toxicity from 50µg/ml, which indicates an inhibitory activity of the leaves of C. coriaceum. The results suggest potential antioxidant, hepatoprotective, anti-inflammatory, antimicrobial, antitumor and neuroprotective activities of C. coriaceum. The second phase aimed to study AD and the potential use of medicinal plants in the treatment of the disease. A literature review was carried out, including papers relevant between 2000 and 2021, publications in databases indexed in SciFinder, Virtual Health Library (VHL), Pubmed, Scientific Electronic Library Online (SCIELO), CAPES café, ScienceDirect, Medline, Bireme and Google academic. 97 articles were initially found, however 81 articles were available in full. Articles that dealt superficially with the theme were removed, leaving 75 articles. It was possible to understand that, in patients who use herbal medicine in the treatment of AD, improvements were identified in cerebral blood flow, elevation of nicotinic receptors, leading to improvements in cognition, memory and delay in neurodegenerative evolution.