Anti-Alzheimer Effects of Some Flavanoids from Plant and Natural Sources; Molecular Review

Abstract

Neuroinflammation, toxic protein aggregation, oxidative stress and mitochondrial dysfunction are key pathways in neurodegenerative diseases such as Alzheimer's disease (AD). Alzheimer's Disease (AD) is a progressive neurodegenerative disease that impairs cognitive functions and memory in the elderly. Current treatment options are limited, so alternative treatments such as herbal medicine may suppress symptoms while slowing cognitive decline. Kaempferol and quercetin, found in plants such as Ginkgo biloba, Camellia sinensis, Glycyrrhiza uralensis, Cyperus rotundus and Buplerum falcatum, are flavonoids with polyphenolic structures that show multiple mechanisms of action, such as inhibition of Aβ plaque formation, reduction of tau hyperphosphorylation, suppression of oxidative stress and modulation of BDNF and PI3K/AKT pathways. Naringenin can significantly reduce Aβ accumulation, microglial and astrocytic activation, and proinflammatory cytokine levels, as well as attenuate neuroinflammatory responses via inhibition of the MAPK signaling pathway in vivo and in vitro. Apigenin is commonly found in vegetables such as parsley, celery, onion, and herbs such as chamomile, thyme, marjoram, and basil. Numerous studies have reported that apigenin exhibits various pharmacological functions and has the potential to be a therapeutic agent for inflammation and neurodegenerative-related diseases. Pinocembrin, found in medicinal plants such as Peperomia, Piper genera and Asteraceae family, is known to affect cognitive function and protect nerve cells against toxicity caused by Aβ. Eriodictyol is a natural flavonoid found mainly in citrus fruits and peanuts. Eriodictyol reduces lipopolysaccharide-induced amyloid production, glial activation and excessive release of cytokines, prevents neuronal damage and protects cognitive function by balancing the cholinergic system in the body.

Keywords

• Alzheimer hastalığı
• nöroinflamasyon
• enzim inhisyonu
• flavonoid

Bitkisel ve Doğal Kaynaklı Bazı Flavanoidlerin anti-Alzheimer Etkileri; Moleküler İnceleme

Abstract

Nöroinflamasyon, toksik protein agregasyonu, oksidatif stres ve mitokondriyal disfonksiyon, Alzheimer hastalığı (AH) gibi nörodejeneratif hastalıklarda temel yollardır. Mevcut tedavi seçenekleri sınırlıdır, bu nedenle bitkisel ilaç gibi alternatif tedaviler bilişsel gerilemeyi yavaşlatırken semptomları baskılayabilir. Ginkgo biloba, Camellia sinensis, Glycyrrhiza uralensis, Cyperus rotundus ve Buplerum falcatum gibi bitkilerde bulunan kaempferol ve kuersetin, Aβ plak oluşumunun inhibisyonu, tau hiperfosforilasyonunda azalma, oksidatif stresin baskılanması ve BDNF ve PI3K/AKT yollarının modülasyonu gibi çoklu etki mekanizmaları gösteren polifenolik yapıya sahip flavonoidlerdir. Naringenin Aβ birikimi, mikroglial ve astrositik aktivasyonu ve proinflamatuar sitokin seviyelerini önemli ölçüde azaltabildiği gibi in vivo ve in vitro MAPK sinyal yolunun inhibisyonu yoluyla nöroinflamatuar yanıtları zayıflatabilmektedir. Apigenin, maydanoz, kereviz, soğan gibi sebzelerde ve papatya, kekik, mercanköşk, fesleğen gibi otlarda yaygın olarak bulunur. Çok sayıda çalışma, apigeninin çeşitli farmakolojik işlevler sergilediğini ve inflamasyon ve nörodejeneratif ilişkili hastalıklar için terapötik bir ajan olma potansiyeline sahip olduğunu bildirmiştir. Peperomia, Piper genera ve Asteraceae familyası gibi medisinal bitkilerde bulunan pinosembrinin bilişsel işlevi etkilediği ve sinir hücrelerini Aβ'dan kaynaklanan toksisiteye karşı koruduğu bilinmektedir. Eriodiktiol, esas olarak turunçgillerde ve fıstıkta bulunan doğal bir flavonoiddir. Eriodiktiol lipopolisakkarit uyarılı amiloid üretimini, glial aktivasyonu ve sitokinlerin aşırı salınımını azaltmakta,. nöronal hasarı engellemekte ve vücuttaki kolinerjik sistemin dengesini sağlayarak bilişsel işlevi korumaktadır.

Keywords

• Alzheimer hastalığı
• nöroinflamasyon
• enzim inhisyonu
• flavonoid

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