Linalool vs linalool-loaded chitosan nanoparticles in an Aβ-induced rat model of Alzheimer’s disease: A molecular, biochemical, histological, and behavioral study

Document Type : Original Article

Authors

1 Department of Biology, SR.C., Islamic Azad University, Tehran, Iran

2 Department of Physiology, Za.C., Islamic Azad University, Zanjan, Iran

3 Department of Physiology, Faculty of Medicine, Arak University of Medical Sciences, Arak, Iran

10.22038/ijbms.2025.88638.19143

Abstract

Objective(s): Recent studies have increasingly focused on applying nanotechnology to treat neurodegenerative diseases. In this study, we compared the effects of the monoterpene linalool and linalool-loaded chitosan nanoparticles on key pathological features of Alzheimer’s disease (AD), including oxidative stress, neuroinflammation, neuronal death, amyloid plaque deposition, alterations in tryptophan metabolism, and memory deficit in a rat model of AD. 
Materials and Methods: An intracerebroventricular injection of Aβ42 (10 µg) was used to induce the AD model. Linalool (25 mg/kg) and nano-linalool (25 mg/kg) were administered orally once daily for 30 consecutive days. 
Results: Both linalool and nano-linalool significantly reduced malondialdehyde levels and enhanced superoxide dismutase activity in the hippocampus. They also decreased the mRNA levels of monocyte chemoattractant protein-1, inhibited the up-regulation of beta-secretase, reduced amyloid plaque deposition, and attenuated pyramidal neuron death in the CA1 region. Additionally, treatment with both compounds down-regulated indoleamine 2,3-dioxygenase, lowered kynurenine levels, and increased serotonin concentrations in the hippocampus. Although both treatments improved learning and spatial memory in Aβ-injected rats, nano-linalool’s effectiveness was more significant than that of linalool in modulating the molecular, biochemical, and histological parameters.
Conclusion: Encapsulating linalool in chitosan nanoparticles enhances its effectiveness in improving molecular, biochemical, and histological changes in the hippocampus of rat models of AD.

Keywords

Main Subjects

References

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Iranian Journal of Basic Medical Sciences
Volume 28, Issue 11
November 2025
Pages 1495-1504

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