Alzheimer's disease (AD) is a progressive neurodegenerative disorder marked by cognitive decline, synaptic dysfunction, and mitochondrial abnormalities. Mitochondrial dynamics, especially the balance Show more
Alzheimer's disease (AD) is a progressive neurodegenerative disorder marked by cognitive decline, synaptic dysfunction, and mitochondrial abnormalities. Mitochondrial dynamics, especially the balance between fusion and fission processes regulated by proteins like mitofusin 2 (Mfn2) and dynamin-related protein 1 (Drp1), play critical roles in neuronal health. However, the relationship between mitochondrial dynamics and synaptic integrity, and cognitive deficits remains incompletely understood. This study aimed to investigate the alterations in Mfn2 and Drp1 expression and their association with synaptic protein levels and also behavioral outcomes in a rat model of AD. Thirty adult male Wistar rats were randomly assigned to control and AD groups. AD was induced through bilateral hippocampal injection of Aβ1-42. Behavioral assessments including the Morris Water Maze, Novel Object Recognition, and Y-maze were conducted to evaluate spatial learning and memory. On day 21 post-induction, gene expression of Drp1, Mfn2, PSD-95, synaptophysin, BDNF, Bax, and Bcl2 in the hippocampus and cortex was measured using real-time PCR. Oxidative stress markers (MDA, SOD, CAT) and inflammatory cytokines (NF-κB, IL-1β) were evaluated in serum using ELISA kits. Results showed significant downregulation of Mfn2 and synaptic proteins, with increased Drp1 and Bax expression in AD rats. These molecular changes were accompanied with increase of oxidative and inflammatory markers and altered cognitive performance. In conclusion, the findings suggest that disrupted mitochondrial dynamics contribute to synaptic loss and cognitive decline in AD. Targeting mitochondrial function and neuroinflammation may represent potential therapeutic targets for AD management. Show less
Decline in mitochondrial quality is a prominent pathological feature of Alzheimer's disease (AD), manifested by impaired energy metabolism, disrupted mitochondrial biogenesis, abnormal mitochondrial d Show more
Decline in mitochondrial quality is a prominent pathological feature of Alzheimer's disease (AD), manifested by impaired energy metabolism, disrupted mitochondrial biogenesis, abnormal mitochondrial dynamics, and defective mitophagy. Increasing evidence indicates that mitochondrial dysfunction contributes to the exacerbation of amyloid-β (Aβ) deposition and tau protein hyperphosphorylation, thereby accelerating AD pathogenesis. Of particular interest, physical exercise has been shown to effectively enhance mitochondrial quality and help prevent or slow the progression of AD, largely through the activation of key signaling pathways such as adenosine monophosphate-activated protein kinase (AMPK) and sirtuin 1 (SIRT1). However, regular physical activity may not be feasible for individuals in the prodromal or clinical stages of AD. In this context, exercise mimetics-compounds that pharmacologically simulate the molecular effects of exercise-have emerged as a promising alternative intervention. This review analyzes the mechanistic roles of exercise mimetics in improving mitochondrial quality under AD conditions, with a focus on their regulation of mitochondrial homeostasis via key signaling pathways. It further aims to provide theoretical insight for the development of mitochondria-targeted exercise mimetics and offer a potential strategy for addressing the growing global burden of AD. Show less
Oxidative stress-induced enteric neuropathy is a key driver of slow-transit constipation (STC), primarily through disrupted mitochondrial dynamics and neuronal degeneration. To address this, we develo Show more
Oxidative stress-induced enteric neuropathy is a key driver of slow-transit constipation (STC), primarily through disrupted mitochondrial dynamics and neuronal degeneration. To address this, we developed a bioengineered oral delivery system that supports neuronal recovery and actively enhances mitochondrial membrane fusion. A self-assembling amphiphilic peptide (GFF) was synthesized to encapsulate rhein (RH), a natural anthraquinone with antioxidant, anti-inflammatory, and microbiota-regulating properties. A BDNF-derived tetrapeptide was integrated to further potentiate neurotrophic effects. These components were co-assembled into a therapeutic nanofiber (RFI), which was embedded in a chitosan/sodium alginate hydrogel for sustained oral delivery. In vitro and in vivo studies demonstrated that RFI significantly improved neuronal viability and gastrointestinal motility. Mechanistic investigations revealed that RFI is associated with activation of the AKT signaling pathway and enhancement of mitochondrial membrane fusion, collectively contributing to the restoration of mitochondrial network integrity and neuronal protection. This multifunctional nanoplatform offers a promising therapeutic approach to STC by combining targeted delivery with direct modulation of mitochondrial function. Show less