A study on alpha-terpineol in Alzheimer’s disease with the use of rodent in vivo model, restraint stress effect and in vitro Amyloid beta fibrils

Abstract

Alzheimer's disease (AD) is a neurological disorder in which the neuronal degeneration is associated with inflammatory processes and oxidative stress. Since alpha-terpineol was shown to possess antioxidant and anti-inflammatory effects, the administration of this compound was studied on a rat model of AD. To create this model, Aβ1-42 was injected into the hippocampus of male Wistar rats. Generated AD models were divided into simple AD models and AD models in which short-term immobilization stress was added. Preventive and therapeutic (post-AD induction) effects of alpha-terpineol consumption (100 mg/Kg) were subsequently investigated in AD models, which were compared with control groups. Biochemical factors (superoxide dismutase and malondialdehyde), histological manifestations (amyloid plaques and neuron counts) and possible memory impairment (shuttle-box experiment) were investigated in all groups. For the in vitro experiment, alpha-terpineol effect was checked on Aβ1-42 fibril formation. In preventive and therapeutic modes, alpha-terpineol consumption could improve neurogenesis and long-term memory while reducing amyloid plaque counts and ameliorating biochemical factors (higher levels of superoxide dismutase and malondialdehyde and reduced levels of MDA). In vitro, shorter fibrillar structures were formed in the presence of alphaterpineol, which indicates an anti-amyloid effect for this compound. In conclusion, alphaterpineol significantly counteracted AD consequences.

7-ketocholesterol enhances BACE1-amyloid precursor protein cleavage and amyloidogenic peptide generation targeted by natural molecules

“…Similarly, the previous reports with monoterpenes of various origin claim to have the anti-amyloidogenic property in in vitro and in vivo models [88]. Supporting our results, monoterpenes alpha-terpeniol, myrcene checked against Aβ bril formation, counteracted AD consequences by reducing bril formation [89,90].…”

Cognition enhancing activity of essential oil of Hedychium coronarium j. Koenig in memory-impaired animal models

“…Our current study attempted this using an essential oil of the plant Hedychium coronarium (HC). Hedychium coronarium is a perennial erect herb with a wide range of biological activity, including considerable cytotoxic and antiinflammatory, anti-tumor, anti-allergic, analgesic, and antihelmintic properties (5).…”

“…The spectrophotometric technique developed by Ellman et al was used to measure the cholinesterase inhibitory activity. The previously published method was used to produce AChE from mouse brain homogenate (5). In brief, brain tissues were collected from mice, homogenized in 50mM Tris-HCl (pH 7.4) containing 1.0M NaCl and 50mM MgCl2, and then centrifuged at 5,000 rpm for 20 minutes at 4°C to yield the crude AChE.…”

“…Hedychium coronarium's leaves and rhizomes are used to produce the volatile oils, which contain a variety of compounds including linalool, limonene, 1,8-cineole, terpinene, α-terpineol, and terpinolene, as well as borneol and other volatile oils. AChE is inhibited by 1,8-cineole; α-terpineol reduces brain plaques and enhances neurogenesis and memory; αand β-pinene and other compounds lessen oxidative stress and exhibit antioxidant activity (3)(4)(5). Therefore, the goal of the current study was designed to evaluate the essential oil of the white ginger lily plant (Hedychium coronarium) for an AChE inhibition and antioxidant activity in vitro and for cognition-enhancing and neuroprotective effect in AlCl3-induced zebrafish and mice model of memory impairment.…”

Mixture design of α‐pinene, α‐terpineol, and 1,8‐cineole: A multiobjective response followed by chemometric approaches to optimize the antibacterial effect against various bacteria and antioxidant activity

“…There is extensive evidence that the monoterpenoid 1,8-cineole has numerous anti-inflammatory and health-promoting effects on various human diseases (Zuo et al, 2020). In addition, α-terpineol exhibits antioxidant activity, as it can suppress superoxide production (Alipour et al, 2022). Ben Hsouna, Michalak, Ben Akacha, et al, 2022).…”