Mitochondria are dynamic ATP-generating organelle which contribute to many cellular functions including bioenergetics processes, intracellular calcium regulation, alteration of reduction-oxidation potential of cells, free radical scavenging, and activation of caspase mediated cell death. Mitochondrial functions can be negatively affected by amyloidβpeptide (Aβ), an important component in Alzheimer’s disease (AD) pathogenesis, and Aβcan interact with mitochondria and cause mitochondrial dysfunction. One of the most accepted hypotheses for AD onset implicates that mitochondrial dysfunction and oxidative stress are one of the primary events in the insurgence of the pathology. Here, we examine structural and functional mitochondrial changes in presence of Aβ. In particular we review data concerning Aβimport into mitochondrion and its involvement in mitochondrial oxidative stress, bioenergetics, biogenesis, trafficking, mitochondrial permeability transition pore (mPTP) formation, and mitochondrial protein interaction. Moreover, the development of AD therapy targeting mitochondria is also discussed.
Oxidative stress and dysfunctional mitochondria are among the earliest events in AD, triggering neurodegeneration. The use of natural antioxidants could be a neuroprotective strategy for blocking cell death. Here, the antioxidant action of ferulic acid (FA) on different paths leading to degeneration of recombinant β-amyloid peptide (rAβ42) treated cells was investigated. Further, to improve its delivery, a novel drug delivery system (DDS) was used. Solid lipid nanoparticles (SLNs), empty or containing ferulic acid (FA-SNL), were developed as DDS. The resulting particles had small colloidal size and highly negative surface charge in water. Using neuroblastoma cells and rAβ42 oligomers, it was demonstrated that free and SLNs-loaded FA recover cell viability. FA treatment, in particular if loaded into SLNs, decreased ROS generation, restored mitochondrial membrane potential (Δψm) and reduced cytochrome c release and intrinsic pathway apoptosis activation. Further, FA modulated the expression of Peroxiredoxin, an anti-oxidative protein, and attenuated phosphorylation of ERK1/2 activated by Aβ oligomers.
1 May 2015 in Biochimica et Biophysica Acta (BBA) - Molecular Cell Research
Alzheimer’s disease (AD) is an aging-related multi-factorial disorder to which metabolic factors contribute at what has canonically been considered a centrally mediated process. Although the exact underlying mechanisms are still unknown, obesity is recognized as a risk factor for AD and the condition of insulin resistance seems to be the link between the two pathologies. Using mice with high fat diet (HFD) obesity we dissected the molecular mechanisms shared by the two disorders. Brains of HFD fed mice showed elevated levels of APP and Aβ40/Aβ42 together with BACE, GSK3β and Tau proteins involved in APP processing and Aβ accumulation. Immunofluorescence, Thioflavin T staining experiments, confirmed increased Aβ generation, deposition in insoluble fraction and plaques formation in both the hippocampus and the cerebral cortex of HFD mice. Presence of Aβ40/Aβ42 in the insoluble fraction was also shown by ELISA assay. Brain insulin resistance was demonstrated by reduced presence of insulin receptor (IRs) and defects in Akt-Foxo3a insulin signaling. We found reduced levels of phospho-Akt and increased levels of Foxo3a in the nuclei of neurons where proapototic genes were activated. Dysregulation of different genes related to insulin resistance, especially those involved in inflammation and adipocytokines synthesis were analyzed by Profiler PCR array. Further, HFD induced oxidative stress, mitochondrial dysfunction and dynamics as demonstrated by expression of biomarkers involved in these processes. Here, we provide evidence that obesity and AD markers besides insulin resistance are associated with inflammation, adipokine dyshomeostasis, oxidative stress and mitochondrial dysfunction, all mechanisms leading to neurodegeneration.
Oxidative stress has long been linked to neuronal cell death that is associated with certain neurodegenerative conditions. Whether it is a primary cause or merely a downstream consequence of the neurodegenerative and aging process is still an open question. Mitochondria are deeply involved in the production of reactive oxygen species through the electron carriers of the respiratory chain and their role in neurodegenerative diseases is discussed here. Moreover, the input of new technological approaches in the study of oxidative stress response or in the evidence of an oxidative stress component in neurodegeneration is reviewed in this paper.
Mitochondrial dysfunction contributes to aging and diseases like neurodegeneration and cardiovascular disorders. Mitochondria transfer and transplantation (MTT) represent promising therapeutic strategies aimed at restoring cellular function by introducing functional mitochondria into damaged cells. However, challenges like transfer efficiency, stability, and cellular integration limit clinical application. Recent biotechnological advances—such as liposomes, extracellular vesicles, and surface modifications—enhance mitochondrial protection, targeting, and biocompatibility. This Perspective highlights recent progress in MTT, its therapeutic potential, and current limitations. We also discuss the need for scalable, clinically translatable approaches and appropriate regulatory frameworks to realize the full potential of mitochondria-based nanotherapies in modern medicine.