scholarly journals Mitochondrial Dysfunction: a Notable Contributor to the Progression of Alzheimer’s & Parkinson’s Disease

Author(s):  
Abolaji Samson Olagunju ◽  
Abiola Adeyanju Alagbe ◽  
Titilayomi Ayomide Otenaike ◽  
Babatunde Oladayo Fabiyi ◽  
John Oluwafemi Teibo ◽  
...  

Mitochondrial dysfunctions remained a pivotal mechanism in manifold neurodegenerative diseases. Mitochondrial homeostasis within the cell is an essential aspect of cell biology. Mitochondria which is also known as the power-generating set of the cell, have a dominant role in several processes associated with the genomic integrity and cellular equilibrium maintenance. They are involved in maintaining optimal cells functioning and guidance from possible DNA damage which could lead to mutations and onset of diseases. Conversely, system perturbations which could be due to environmental factors or senescence induce changes in the physiological balance and result in the mitochondrial functions impairment. The focal point of this review focuses on mitochondrial dysfunction as a significant condition in the onset of neuronal disintegration. We explain the pathways associated with the dysfunction of the mitochondria which are common amongst the most recurring neurodegenerative diseases including Alzheimers and Parkinsons disease. Do mitochondrial dysfunctions represent an early event in causing a shift towards neuropathological processes?

2020 ◽  
Vol 21 (10) ◽  
pp. 3719 ◽  
Author(s):  
Serena Stanga ◽  
Anna Caretto ◽  
Marina Boido ◽  
Alessandro Vercelli

Mitochondria play a central role in a plethora of processes related to the maintenance of cellular homeostasis and genomic integrity. They contribute to preserving the optimal functioning of cells and protecting them from potential DNA damage which could result in mutations and disease. However, perturbations of the system due to senescence or environmental factors induce alterations of the physiological balance and lead to the impairment of mitochondrial functions. After the description of the crucial roles of mitochondria for cell survival and activity, the core of this review focuses on the “mitochondrial switch” which occurs at the onset of neuronal degeneration. We dissect the pathways related to mitochondrial dysfunctions which are shared among the most frequent or disabling neurodegenerative diseases such as Alzheimer’s, Parkinson’s, and Huntington’s, Amyotrophic Lateral Sclerosis, and Spinal Muscular Atrophy. Can mitochondrial dysfunctions (affecting their morphology and activities) represent the early event eliciting the shift towards pathological neurobiological processes? Can mitochondria represent a common target against neurodegeneration? We also review here the drugs that target mitochondria in neurodegenerative diseases.


2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Shuiqiao Liu ◽  
Mi Zhou ◽  
Zhi Ruan ◽  
Yanan Wang ◽  
Calvin Chang ◽  
...  

Abstract Background Apoptosis-inducing factor (AIF), as a mitochondrial flavoprotein, plays a fundamental role in mitochondrial bioenergetics that is critical for cell survival and also mediates caspase-independent cell death once it is released from mitochondria and translocated to the nucleus under ischemic stroke or neurodegenerative diseases. Although alternative splicing regulation of AIF has been implicated, it remains unknown which AIF splicing isoform will be induced under pathological conditions and how it impacts mitochondrial functions and neurodegeneration in adult brain. Methods AIF splicing induction in brain was determined by multiple approaches including 5′ RACE, Sanger sequencing, splicing-specific PCR assay and bottom-up proteomic analysis. The role of AIF splicing in mitochondria and neurodegeneration was determined by its biochemical properties, cell death analysis, morphological and functional alterations and animal behavior. Three animal models, including loss-of-function harlequin model, gain-of-function AIF3 knockin model and conditional inducible AIF splicing model established using either Cre-loxp recombination or CRISPR/Cas9 techniques, were applied to explore underlying mechanisms of AIF splicing-induced neurodegeneration. Results We identified a nature splicing AIF isoform lacking exons 2 and 3 named as AIF3. AIF3 was undetectable under physiological conditions but its expression was increased in mouse and human postmortem brain after stroke. AIF3 splicing in mouse brain caused enlarged ventricles and severe neurodegeneration in the forebrain regions. These AIF3 splicing mice died 2–4 months after birth. AIF3 splicing-triggered neurodegeneration involves both mitochondrial dysfunction and AIF3 nuclear translocation. We showed that AIF3 inhibited NADH oxidase activity, ATP production, oxygen consumption, and mitochondrial biogenesis. In addition, expression of AIF3 significantly increased chromatin condensation and nuclear shrinkage leading to neuronal cell death. However, loss-of-AIF alone in harlequin or gain-of-AIF3 alone in AIF3 knockin mice did not cause robust neurodegeneration as that observed in AIF3 splicing mice. Conclusions We identified AIF3 as a disease-inducible isoform and established AIF3 splicing mouse model. The molecular mechanism underlying AIF3 splicing-induced neurodegeneration involves mitochondrial dysfunction and AIF3 nuclear translocation resulting from the synergistic effect of loss-of-AIF and gain-of-AIF3. Our study provides a valuable tool to understand the role of AIF3 splicing in brain and a potential therapeutic target to prevent/delay the progress of neurodegenerative diseases.


2021 ◽  
Vol 10 (4) ◽  
pp. 147-149
Author(s):  
Ratan Kumari ◽  
Nikhila Shekhar ◽  
Sakshi Tyagi ◽  
Ajit Kumar Thakur

Mitochondrial dysfunction is estimated to be the primary reason involved in different types of neurodegenerative disorders as mitochondria is suggested to be important in the production of reactive oxygen species. Recently, several evidences have emerged out for impaired mitochondrial structures and functions viz. shape, size, fission-fusion, distribution, movement etc. in neurodegenerative diseases especially with Alzheimer’s disease, Parkinson’s disease and Huntington’s disease. Therefore, apart from looking neurodegenerative diseases on the whole, a detailed understanding of the functioning of mitochondria and their role in degeneration would pave new options for the therapy of age-related neurodegenerative diseases.


2020 ◽  
Vol 21 ◽  
Author(s):  
Vipin Dhote ◽  
Prem Samundre ◽  
Aditya Ganeshpurkar ◽  
Aman Upaganlawar

Abstract:: Advancing age presents a major challenge for the elderly population in terms of quality of life. The risk of cognitive impairment, motor in-coordination, and behavioral inconsistency due to neuronal damage is relatively higher in aging individuals of society. The brain, through its structural and functional integrity, regulates vital physiological events; however, the susceptibility of the brain to aging-related disturbances signal the onset of neurodegenerative diseases. Mitochondrial dysfunctions impair bioenergetic mechanism, synaptic plasticity, and calcium homeostasis in the brain, thus sufficiently implying mitochondria as a prime causal factor in accelerating aging-related neurodegeneration. We reviewed the fundamental functions of mitochondria in a healthy brain and aimed to address the key issues in aging-related diseases by asking: 1) What goes wrong with mitochondria in the aging brain? 2) What are the implications of mitochondrial damage on motor functions and psychiatric symptoms? 3) How environmental chemicals and metabolic morbidities affect mitochondrial functions? Further, we share insight on opportunities and pitfalls in drug discovery approaches targeting mitochondria to slow down the progression of aging and related neurodegenerative diseases.


2021 ◽  
Vol 12 (2) ◽  
Author(s):  
Xingting Bao ◽  
Jinhua Zhang ◽  
Guomin Huang ◽  
Junfang Yan ◽  
Caipeng Xu ◽  
...  

AbstractMitochondria are essential cellular organelles that are involved in regulating cellular energy, metabolism, survival, and proliferation. To some extent, cancer is a genetic and metabolic disease that is closely associated with mitochondrial dysfunction. Hypoxia-inducible factors (HIFs), which are major molecules that respond to hypoxia, play important roles in cancer development by participating in multiple processes, such as metabolism, proliferation, and angiogenesis. The Warburg phenomenon reflects a pseudo-hypoxic state that activates HIF-1α. In addition, a product of the Warburg effect, lactate, also induces HIF-1α. However, Warburg proposed that aerobic glycolysis occurs due to a defect in mitochondria. Moreover, both HIFs and mitochondrial dysfunction can lead to complex reprogramming of energy metabolism, including reduced mitochondrial oxidative metabolism, increased glucose uptake, and enhanced anaerobic glycolysis. Thus, there may be a connection between HIFs and mitochondrial dysfunction. In this review, we systematically discuss the crosstalk between HIFs and mitochondrial dysfunctions in cancer development. Above all, the stability and activity of HIFs are closely influenced by mitochondrial dysfunction related to tricarboxylic acid cycle, electron transport chain components, mitochondrial respiration, and mitochondrial-related proteins. Furthermore, activation of HIFs can lead to mitochondrial dysfunction by affecting multiple mitochondrial functions, including mitochondrial oxidative capacity, biogenesis, apoptosis, fission, and autophagy. In general, the regulation of tumorigenesis and development by HIFs and mitochondrial dysfunction are part of an extensive and cooperative network.


2020 ◽  
Vol 26 (12) ◽  
pp. 1251-1262 ◽  
Author(s):  
Octavio Binvignat ◽  
Jordi Olloquequi

: The global burden of neurodegenerative diseases is alarmingly increasing in parallel to the aging of population. Although the molecular mechanisms leading to neurodegeneration are not completely understood, excitotoxicity, defined as the injury and death of neurons due to excessive or prolonged exposure to excitatory amino acids, has been shown to play a pivotal role. The increased release and/or decreased uptake of glutamate results in dysregulation of neuronal calcium homeostasis, leading to oxidative stress, mitochondrial dysfunctions, disturbances in protein turn-over and neuroinflammation. : Despite the anti-excitotoxic drug memantine has shown modest beneficial effects in some patients with dementia, to date, there is no effective treatment capable of halting or curing neurodegenerative diseases such as Alzheimer’s disease, Parkinson disease, Huntington’s disease or amyotrophic lateral sclerosis. This has led to a growing body of research focusing on understanding the mechanisms associated with the excitotoxic insult and on uncovering potential therapeutic strategies targeting these mechanisms. : In the present review, we examine the molecular mechanisms related to excitotoxic cell death. Moreover, we provide a comprehensive and updated state of the art of preclinical and clinical investigations targeting excitotoxic- related mechanisms in order to provide an effective treatment against neurodegeneration.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Vaibhav S. Marde ◽  
Prerna L. Tiwari ◽  
Nitu L. Wankhede ◽  
Brijesh G. Taksande ◽  
Aman B. Upaganlawar ◽  
...  

Abstract Background Over the last decade, aggregating evidences suggested that there is a causative link between mutation in gene associated with mitochondrial dysfunction and development of several neurodegenerative disorders. Main text Recent structural and functional studies associated with mitochondrial genes have shown that mitochondrial abnormalities possibly lead to mitochondrial dysfunction. Several studies on animal models of neurodegenerative diseases and mitochondrial genes have provided compelling evidence that mitochondria is involved in the initiation as well as progression of diseases such as Parkinson’s disease (PD), Alzheimer’s disease (AD), Huntington’s disease (HD), and Friedreich ataxia (FA). Conclusion In this mini-review, we have discussed the different etiologic and pathogenesis connected with the mitochondrial dysfunction and relevant neurodegenerative diseases that underlie the dominant part of mitochondrial genes in the disease development and its progress.


2021 ◽  
Vol 22 (2) ◽  
pp. 934
Author(s):  
Woon-Man Kung ◽  
Muh-Shi Lin

Proinflammatory response and mitochondrial dysfunction are related to the pathogenesis of neurodegenerative diseases (NDs). Nuclear factor κB (NFκB) activation has been shown to exaggerate proinflammation and mitochondrial dysfunction, which underlies NDs. CDGSH iron-sulfur domain 2 (CISD2) has been shown to be associated with peroxisome proliferator-activated receptor-β (PPAR-β) to compete for NFκB and antagonize the two aforementioned NFκB-provoked pathogeneses. Therefore, CISD2-based strategies hold promise in the treatment of NDs. CISD2 protein belongs to the human NEET protein family and is encoded by the CISD2 gene (located at 4q24 in humans). In CISD2, the [2Fe-2S] cluster, through coordinates of 3-cysteine-1-histidine on the CDGSH domain, acts as a homeostasis regulator under environmental stress through the transfer of electrons or iron-sulfur clusters. Here, we have summarized the features of CISD2 in genetics and clinics, briefly outlined the role of CISD2 as a key physiological regulator, and presented modalities to increase CISD2 activity, including biomedical engineering or pharmacological management. Strategies to increase CISD2 activity can be beneficial for the prevention of inflammation and mitochondrial dysfunction, and thus, they can be applied in the management of NDs.


Life ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 371
Author(s):  
Filipa Barroso Gonçalves ◽  
Vanessa Alexandra Morais

Mitochondria are known as highly dynamic organelles essential for energy production. Intriguingly, in the recent years, mitochondria have revealed the ability to maintain cell homeostasis and ultimately regulate cell fate. This regulation is achieved by evoking mitochondrial quality control pathways that are capable of sensing the overall status of the cellular environment. In a first instance, actions to maintain a robust pool of mitochondria take place; however, if unsuccessful, measures that lead to overall cell death occur. One of the central key players of these mitochondrial quality control pathways is PINK1 (PTEN-induce putative kinase), a mitochondrial targeted kinase. PINK1 is known to interact with several substrates to regulate mitochondrial functions, and not only is responsible for triggering mitochondrial clearance via mitophagy, but also participates in maintenance of mitochondrial functions and homeostasis, under healthy conditions. Moreover, PINK1 has been associated with the familial form of Parkinson’s disease (PD). Growing evidence has strongly linked mitochondrial homeostasis to the central nervous system (CNS), a system that is replenished with high energy demanding long-lasting neuronal cells. Moreover, sporadic cases of PD have also revealed mitochondrial impairments. Thus, one could speculate that mitochondrial homeostasis is the common denominator in these two forms of the disease, and PINK1 may play a central role in maintaining mitochondrial homeostasis. In this review, we will discuss the role of PINK1 in the mitochondrial physiology and scrutinize its role in the cascade of PD pathology.


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