Lamiaceae Family Plants as a Potential Anticholinesterase Source in the Treatment of Alzheimer’s Disease

Abstract

Alzheimer's disease (AD) is one of the most common and progressive neurodegenerative disorders with dementia in the world. The precise causes of AD are not fully understood yet, although several important features of its pathophysiology are well described. Current AD treatment is symptomatic and is mainly, but not exclusively, focused on the inhibition of cholinesterases (ChEs). There are four cholinesterase inhibitors approved by the U.S. Food and Drug Administration (FDA): tacrine, donepezil, rivastigmine, and galantamine. Among them, galantamine is a natural drug, and rivastigmine is a derivative of the natural drug physostigmine. In addition, only an NMDA (N-methyl-D-aspartate) receptor antagonist, memantine, is also approved by the FDA in the treatment of patients with moderate to severe AD. However, none of them provides a satisfactory treatment for Alzheimer's disease, and studies are still going on to find new potential drugs from both synthetic chemicals and natural sources. In this review, studies on the discovery of new cholinesterase inhibitors from natural sources, particularly from Lamiaceae family plants were evaluated, and a number of terpenoids and phenolics/flavonoids isolated are presented as potential drugs in the treatment of Alzheimer's disease.

Antioxidant and anticholinesterase activities of lupane triterpenoids and other constituents of Salvia trichoclada

“…In another study, triterpenoids 5 and 6 were found not to be active in the DPPH scavenging activity test assay (Giuseppe et al, 2006). In fact, both triterpenic acids exhibited more or less lipid peroxidation inhibitory activity in several studies, particularly ursolic acid showed higher activity than oleanolic acid (Topcu et al, 2013;Topcu and Kusman, 2014). Compound 7 (bsitosterol) did not show any antioxidant activity in our study correlating to the results in the previous studies (Giuseppe et al, 2006;Hung and Yen 2001).…”

“…In Anatolia some Salvia species have also been used as neuroprotective agents. Some Turkish Salvia extracts have also been investigated for their AChE and BChE inhibitory activities (Orhan et al, 2007;Topcu and Kusman, 2014).…”

Sideritis scardica Griseb.

“…Dabei ist die antioxidative Wirkung der Blätter am stärksten, gefolgt von den Blüten und schließlich den Stängeln, wobei wässrige Extrakte von kultivierten Pflanzen stärker antioxidativ wirksam sind als Methanol-Extrakte [25]. In weiteren Studien wurden für isolierte Diterpene aus Sideritis-Arten antioxidative Wirkungen beschrieben [37].…”

“…Isolierte Diterpene wie Siderol, Sideridiol und Sideroxol können in vitro die Acetylcholin-Esterase (AChE) -zumindest schwach -hemmen [37] und gemäß In-vitro-Daten die Blut-Hirn-Schranke überschreiten [12]. Die Hemmung der AChE ist auch ein Wirkprinzip synthetischer Wirkstoffe bei der Behandlung von Demenz und M. Alzheimer.…”

Study of antimicrobial effect of some plants of Lamiaceae family on Escherichia coli species isolated from children with urinary tract infection

“…The main compounds in the Lamiaceae family plants are flavonoids and polyphenols. These compounds are inhibitors of cholinesterase and their antioxidant and antiinflammatory effects have been reported in several studies (4)(5)(6). In the previous studies, the antimicrobial effects of the essential oils of some members of Lamiaceae family, such as thyme, savory, marjoram, basil and lavender have been investigated (7)(8)(9).…”