ORIGINAL RESEARCH article

Front. Aging Neurosci.

Sec. Cellular and Molecular Mechanisms of Brain-aging

Volume 17 - 2025 | doi: 10.3389/fnagi.2025.1607289

This article is part of the Research TopicBioactive Compounds in Neuroprotection: Unveiling Modern Therapeutics in AgingView all articles

Ambroxol confers neuroprotection against scopolamine-induced Alzheimer's-like pathology by modulating oxidative stress, neuroinflammation, and cognitive deficits via Nrf-2/JNK/GSK-3β signaling pathways

Provisionally accepted
Waqas  AhmadWaqas Ahmad1Kyonghwan  ChoeKyonghwan Choe1Riaz  AhmadRiaz Ahmad1Tae  Ju ParkTae Ju Park2*Myeong Ok  KimMyeong Ok Kim1*
  • 1Gyeongsang National University, Jinju, Republic of Korea
  • 2University of Glasgow, Glasgow, Scotland, United Kingdom

The final, formatted version of the article will be published soon.

Alzheimer's disease (AD) is the most common and costly chronic progressive neurodegenerative disorder, with the highest impact on public health worldwide. Pathological hallmarks of AD include progressive cognitive decline and memory impairment, dominantly mediated by oxidative neurodegeneration. Oxidative stress is commonly recognized as a key factor in the pathophysiological progression of AD. Despite significant advancements, a definitive and effective therapeutic intervention for AD remains elusive. In this study, we investigate the neuroprotective potential of ambroxol (Amb), known for its potent anti-inflammatory and antioxidant properties. Given ambroxol's potential neuroprotective effects, we explore the underlying molecular mechanisms, explicitly examining its role in attenuating scopolamine-induced oxidative stress-mediated activation of the c- Jun N-terminal kinase (JNK) pathway, as well as its modulation of Akt and glycogen synthase kinase-3 beta (GSK-3β) signaling, which is a key contributor to neuroinflammation, synaptic dysfunction and neurodegeneration. AD pathology is induced by scopolamine administration, leading to excessive lipid peroxidation (LPO) and reactive oxygen species (ROS) generation, which leads to a decline in critical antioxidant proteins, including nuclear factor erythroid 2-related factor 2 (Nrf-2) and heme oxygenase-1 (HO-1). However, ambroxol treatment effectively attenuated oxidative stress by reducing the production of reactive oxidative species while restoring the expression of key antioxidant proteins. Similarly, ambroxol attenuated oxidative stress-induced JNK activation and modulated Akt and GSK-3β alterations. Immunofluorescence and western blot analyses revealed that ambroxol attenuated reactive gliosis by suppressing the expression of GFAP and Iba-1, alongside the downregulation of key pro-inflammatory mediators, such as IL-1β, TNF-α, and phosphorylated NF-κB (p-p65). Scopolamine also compromised synaptic integrity and induced deficits in memory formation and spatial learning. In contrast, ambroxol promoted synaptic integrity by upregulating the expression of SNAP-23 and PSD-95, thereby ameliorating scopolamine-induced impairments in spatial learning and memory.

Keywords: Alzheimer's disease, scopolamine, Ambroxol, Oxidative Stress, Neuroinflammation, synaptic dysfunction

Received: 07 Apr 2025; Accepted: 04 Jul 2025.

Copyright: © 2025 Ahmad, Choe, Ahmad, Park and Kim. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

* Correspondence:
Tae Ju Park, University of Glasgow, Glasgow, G12 8QQ, Scotland, United Kingdom
Myeong Ok Kim, Gyeongsang National University, Jinju, Republic of Korea

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