Inhibition of the deubiquitinase USP8 corrects a Drosophila PINK1 model of mitochondria dysfunction

Aberrant mitochondrial dynamics disrupts mitochondrial function and contributes to disease conditions. A targeted RNA interference screen for deubiquitinating enzymes (DUBs) affecting protein levels of multifunctional mitochondrial fusion protein Mitofusin (MFN) identified USP8 prominently influencing MFN levels. Genetic and pharmacological inhibition of USP8 normalized the elevated MFN protein levels observed in PINK1 and Parkin-deficient models. This correlated with improved mitochondrial function, locomotor performance and life span, and prevented dopaminergic neurons loss in Drosophila PINK1 KO flies. We identified a novel target antagonizing pathologically elevated MFN levels, mitochondrial dysfunction, and dopaminergic neuron loss of a Drosophila model of mitochondrial dysfunction.

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Neural stem cells traffic functional mitochondria via extracellular vesicles to correct mitochondrial dysfunction in target cells

10.1101/2020.01.29.923441 ◽

2020 ◽

Author(s):

Luca Peruzzotti-Jametti ◽

Joshua D. Bernstock ◽

Giulia Manferrari ◽

Rebecca Rogall ◽

Erika Fernandez-Vizarra ◽

...

Keyword(s):

Multiple Sclerosis ◽

Stem Cell ◽

Mitochondrial Dysfunction ◽

Extracellular Vesicles ◽

Mitochondrial Function ◽

Mitochondrial Dynamics ◽

Mononuclear Phagocytes ◽

Host Cells ◽

Target Cells ◽

Therapeutic Effects

AbstractNeural stem cell (NSC) transplantation induces recovery in animal models of central nervous system (CNS) diseases. Although the replacement of lost endogenous cells was originally proposed as the primary healing mechanism of NSC grafts, it is now clear that transplanted NSCs operate via multiple mechanisms, including the horizontal exchange of therapeutic cargoes to host cells via extracellular vesicles (EVs).EVs are membrane particles trafficking nucleic acids, proteins, metabolites and metabolic enzymes, lipids and entire organelles. However, the function and the contribution of these cargoes to the broad therapeutic effects of NSCs is yet to be fully understood. Mitochondrial dysfunction is an established feature of several inflammatory and degenerative CNS disorders, most of which are potentially treatable with exogenous stem cell therapeutics.Herein we investigated the hypothesis that NSCs release and traffic functional mitochondria via EVs to restore mitochondrial function in target cells.Untargeted proteomics revealed a significant enrichment of mitochondrial proteins spontaneously released by NSCs in EVs. Morphological and functional analyses confirmed the presence of ultrastructurally intact mitochondria within EVs (Mito-EVs) with conserved membrane potential and respiration. We found that the transfer of Mito-EVs to mtDNA-deficient L929 Rho0 cells rescued mitochondrial function and increased Rho0 cell survival. Furthermore, the incorporation of Mito-EVs into inflammatory professional phagocytes restored normal mitochondrial dynamics and cellular metabolism and reduced the expression of pro-inflammatory markers in target cells. When transplanted in an animal model of multiple sclerosis, exogenous NSCs actively transferred mitochondria to mononuclear phagocytes and induced a significant amelioration of clinical deficits.Our data provide the first evidence that NSCs deliver functional mitochondria to target cells via Mito-EVs, paving the way for the development of novel (a)cellular approaches aimed at restoring mitochondrial dysfunction not only in multiple sclerosis, but also in degenerative neurological diseases.

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Bu-Yin-Qian-Zheng Formula Ameliorates MPP+-Induced Mitochondrial Dysfunction in Parkinson’s Disease via Parkin

Frontiers in Pharmacology ◽

10.3389/fphar.2020.577017 ◽

2020 ◽

Vol 11 ◽

Author(s):

Hao-Jie Ma ◽

Cong Gai ◽

Yuan Chai ◽

Wan-Di Feng ◽

Cui-Cui Cheng ◽

...

Keyword(s):

Protein Expression ◽

Mitochondrial Dysfunction ◽

Cell Survival ◽

Mitochondrial Function ◽

Survival Rates ◽

Transient Transfection ◽

Mitochondrial Fusion ◽

Mitochondrial Morphology ◽

Protein Levels ◽

Atp Levels

As a typical traditional Chinese medicine, Bu-Yin-Qian-Zheng Formula (BYQZF) has been shown to have neuroprotective effects in patients with Parkinson’s disease (PD), particularly by ameliorating mitochondrial dysfunction and regulating expression of the parkin protein. However, the underlying mechanisms by which BYQZF affects mitochondrial function through parkin are unclear. Accordingly, in this study, we evaluated the mechanisms by which BYQZF ameliorates mitochondrial dysfunction through parkin in PD. We constructed a parkin-knockdown cell model and performed fluorescence microscopy to observe transfected SH-SY5Y cells. Quantitative real-time reverse transcription polymerase chain reaction and western blotting were conducted to detect the mRNA and protein expression levels of parkin. Additionally, we evaluated the cell survival rates, ATP levels, mitochondrial membrane potential (ΔΨm), mitochondrial morphology, parkin protein expression, PINK1 protein expression, and mitochondrial fusion and fission protein expression after treatment with MPP+ and BYQZF. Our results showed that cell survival rates, ATP levels, ΔΨm, mitochondrial morphology, parkin protein levels, PINK1 protein levels, and mitochondrial fusion protein levels were reduced after MPP+ treatment. In contrast, mitochondrial fission protein levels were increased after MPP+ treatment. Moreover, after transient transfection with a negative control plasmid, the above indices were significantly increased by BYQZF. However, there were no obvious differences in these indices after transient transfection with a parkin-knockdown plasmid. Our findings suggest that BYQZF has protective effects on mitochondrial function in MPP+-induced SH-SY5Y cells via parkin-dependent regulation of mitochondrial dynamics.

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YiQiFuMai Powder Injection Protects against Ischemic Stroke via Inhibiting Neuronal Apoptosis and PKCδ/Drp1-Mediated Excessive Mitochondrial Fission

Oxidative Medicine and Cellular Longevity ◽

10.1155/2017/1832093 ◽

2017 ◽

Vol 2017 ◽

pp. 1-17 ◽

Cited By ~ 7

Author(s):

Yingqiong Xu ◽

Yan Wang ◽

Guangyun Wang ◽

Xinyi Ye ◽

Jiangwei Zhang ◽

...

Keyword(s):

Oxidative Stress ◽

Ischemic Stroke ◽

Mitochondrial Dysfunction ◽

Mitochondrial Function ◽

Neuronal Apoptosis ◽

Mitochondrial Fission ◽

Powder Injection ◽

Mitochondria Membrane Potential ◽

Protein Levels ◽

Underlying Mechanisms

YiQiFuMai (YQFM) powder injection has been reported to be used in cardiovascular and nervous system diseases with marked efficacy. However, as a treatment against diseases characterized by hypoxia, lassitude, and asthenia, the effects and underlying mechanisms of YQFM in neuronal mitochondrial function and dynamics have not been fully elucidated. Here, we demonstrated that YQFM inhibited mitochondrial apoptosis and activation of dynamin-related protein 1 (Drp1) in cerebral ischemia-injured rats, producing a significant improvement in cerebral infarction and neurological score. YQFM also attenuated oxidative stress-induced mitochondrial dysfunction and apoptosis through increasing ATP level and mitochondria membrane potential (Δψm), inhibiting ROS production, and regulating Bcl-2 family protein levels in primary cultured neurons. Moreover, YQFM inhibited excessive mitochondrial fission, Drp1 phosphorylation, and translocation from cytoplasm to mitochondria induced by oxidative stress. We provided the first evidence that YQFM inhibited the activation, association, and translocation of PKCδ and Drp1 upon oxidative stress. Taken together, we demonstrate that YQFM ameliorates ischemic stroke-induced neuronal apoptosis through inhibiting mitochondrial dysfunction and PKCδ/Drp1-mediated excessive mitochondrial fission. These findings not only put new insights into the unique neuroprotective properties of YQFM associated with the regulation of mitochondrial function but also expand our understanding of the underlying mechanisms of ischemic stroke.

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MicroRNA-709 Mediates Acute Tubular Injury through Effects on Mitochondrial Function

Journal of the American Society of Nephrology ◽

10.1681/asn.2017040381 ◽

2017 ◽

Vol 29 (2) ◽

pp. 449-461 ◽

Cited By ~ 27

Author(s):

Yan Guo ◽

Jiajia Ni ◽

Shuang Chen ◽

Mi Bai ◽

Jiajuan Lin ◽

...

Keyword(s):

Mitochondrial Dysfunction ◽

Mitochondrial Function ◽

Cell Injury ◽

Kidney Tissue ◽

Kidney Injury ◽

Tubular Injury ◽

Pathogenic Role ◽

Novel Target

Mitochondrial dysfunction has important roles in the pathogenesis of AKI, yet therapeutic approaches to improve mitochondrial function remain limited. In this study, we investigated the pathogenic role of microRNA-709 (miR-709) in mediating mitochondrial impairment and tubular cell death in AKI. In a cisplatin-induced AKI mouse model and in biopsy samples of human AKI kidney tissue, miR-709 was significantly upregulated in the proximal tubular cells (PTCs). The expression of miR-709 in the renal PTCs of patients with AKI correlated with the severity of kidney injury. In cultured mouse PTCs, overexpression of miR-709 markedly induced mitochondrial dysfunction and cell apoptosis, and inhibition of miR-709 ameliorated cisplatin-induced mitochondrial dysfunction and cell injury. Further analyses showed that mitochondrial transcriptional factor A (TFAM) is a target gene of miR-709, and genetic restoration of TFAM attenuated mitochondrial dysfunction and cell injury induced by cisplatin or miR-709 overexpression in vitro. Moreover, antagonizing miR-709 with an miR-709 antagomir dramatically attenuated cisplatin-induced kidney injury and mitochondrial dysfunction in mice. Collectively, our results suggest that miR-709 has an important role in mediating cisplatin-induced AKI via negative regulation of TFAM and subsequent mitochondrial dysfunction. These findings reveal a pathogenic role of miR-709 in acute tubular injury and suggest a novel target for the treatment of AKI.

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Mitochondrial Dysfunction and Oxidative Stress in Alzheimer’s Disease

Frontiers in Aging Neuroscience ◽

10.3389/fnagi.2021.617588 ◽

2021 ◽

Vol 13 ◽

Cited By ~ 1

Author(s):

Afzal Misrani ◽

Sidra Tabassum ◽

Li Yang

Keyword(s):

Oxidative Stress ◽

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Mitochondrial Dysfunction ◽

Mitochondrial Function ◽

Mitochondrial Dynamics ◽

Mitochondrial Morphology ◽

Therapeutic Approaches ◽

The Impact ◽

And Oxidative Stress

Mitochondria play a pivotal role in bioenergetics and respiratory functions, which are essential for the numerous biochemical processes underpinning cell viability. Mitochondrial morphology changes rapidly in response to external insults and changes in metabolic status via fission and fusion processes (so-called mitochondrial dynamics) that maintain mitochondrial quality and homeostasis. Damaged mitochondria are removed by a process known as mitophagy, which involves their degradation by a specific autophagosomal pathway. Over the last few years, remarkable efforts have been made to investigate the impact on the pathogenesis of Alzheimer’s disease (AD) of various forms of mitochondrial dysfunction, such as excessive reactive oxygen species (ROS) production, mitochondrial Ca2+ dyshomeostasis, loss of ATP, and defects in mitochondrial dynamics and transport, and mitophagy. Recent research suggests that restoration of mitochondrial function by physical exercise, an antioxidant diet, or therapeutic approaches can delay the onset and slow the progression of AD. In this review, we focus on recent progress that highlights the crucial role of alterations in mitochondrial function and oxidative stress in the pathogenesis of AD, emphasizing a framework of existing and potential therapeutic approaches.

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Activin signaling mediates muscle-to-adipose communication in a mitochondria dysfunction-associated obesity model

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1708037114 ◽

2017 ◽

Vol 114 (32) ◽

pp. 8596-8601 ◽

Cited By ~ 26

Author(s):

Wei Song ◽

Edward Owusu-Ansah ◽

Yanhui Hu ◽

Daojun Cheng ◽

Xiaochun Ni ◽

...

Keyword(s):

Mitochondrial Dysfunction ◽

Mitochondrial Function ◽

Target Genes ◽

Fat Body ◽

Mitochondrial Activity ◽

Rna Seq ◽

Mitochondria Dysfunction ◽

Activin Signaling ◽

Triglyceride Accumulation

Mitochondrial dysfunction has been associated with obesity and metabolic disorders. However, whether mitochondrial perturbation in a single tissue influences mitochondrial function and metabolic status of another distal tissue remains largely unknown. We analyzed the nonautonomous role of muscular mitochondrial dysfunction in Drosophila. Surprisingly, impaired muscle mitochondrial function via complex I perturbation results in simultaneous mitochondrial dysfunction in the fat body (the fly adipose tissue) and subsequent triglyceride accumulation, the major characteristic of obesity. RNA-sequencing (RNA-seq) analysis, in the context of muscle mitochondrial dysfunction, revealed that target genes of the TGF-β signaling pathway were induced in the fat body. Strikingly, expression of the TGF-β family ligand, Activin-β (Actβ), was dramatically increased in the muscles by NF-κB/Relish (Rel) signaling in response to mitochondrial perturbation, and decreasing Actβ expression in mitochondrial-perturbed muscles rescued both the fat body mitochondrial dysfunction and obesity phenotypes. Thus, perturbation of muscle mitochondrial activity regulates mitochondrial function in the fat body nonautonomously via modulation of Activin signaling.

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Neural stem cells traffic functional mitochondria via extracellular vesicles

PLoS Biology ◽

10.1371/journal.pbio.3001166 ◽

2021 ◽

Vol 19 (4) ◽

pp. e3001166

Author(s):

Luca Peruzzotti-Jametti ◽

Joshua D. Bernstock ◽

Cory M. Willis ◽

Giulia Manferrari ◽

Rebecca Rogall ◽

...

Keyword(s):

Multiple Sclerosis ◽

Stem Cell ◽

Mitochondrial Dysfunction ◽

Extracellular Vesicles ◽

Mitochondrial Function ◽

Mitochondrial Dynamics ◽

Mononuclear Phagocytes ◽

Host Cells ◽

Target Cells ◽

Therapeutic Effects

Neural stem cell (NSC) transplantation induces recovery in animal models of central nervous system (CNS) diseases. Although the replacement of lost endogenous cells was originally proposed as the primary healing mechanism of NSC grafts, it is now clear that transplanted NSCs operate via multiple mechanisms, including the horizontal exchange of therapeutic cargoes to host cells via extracellular vesicles (EVs). EVs are membrane particles trafficking nucleic acids, proteins, metabolites and metabolic enzymes, lipids, and entire organelles. However, the function and the contribution of these cargoes to the broad therapeutic effects of NSCs are yet to be fully understood. Mitochondrial dysfunction is an established feature of several inflammatory and degenerative CNS disorders, most of which are potentially treatable with exogenous stem cell therapeutics. Herein, we investigated the hypothesis that NSCs release and traffic functional mitochondria via EVs to restore mitochondrial function in target cells. Untargeted proteomics revealed a significant enrichment of mitochondrial proteins spontaneously released by NSCs in EVs. Morphological and functional analyses confirmed the presence of ultrastructurally intact mitochondria within EVs with conserved membrane potential and respiration. We found that the transfer of these mitochondria from EVs to mtDNA-deficient L929 Rho0 cells rescued mitochondrial function and increased Rho0 cell survival. Furthermore, the incorporation of mitochondria from EVs into inflammatory mononuclear phagocytes restored normal mitochondrial dynamics and cellular metabolism and reduced the expression of pro-inflammatory markers in target cells. When transplanted in an animal model of multiple sclerosis, exogenous NSCs actively transferred mitochondria to mononuclear phagocytes and induced a significant amelioration of clinical deficits. Our data provide the first evidence that NSCs deliver functional mitochondria to target cells via EVs, paving the way for the development of novel (a)cellular approaches aimed at restoring mitochondrial dysfunction not only in multiple sclerosis, but also in degenerative neurological diseases.

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Alpha-synuclein-induced mitochondrial dysfunction is mediated via a sirtuin 3-dependent pathway

10.1101/357624 ◽

2018 ◽

Cited By ~ 1

Author(s):

Jae-Hyeon Park ◽

Marion Delenclos ◽

Ayman H. Faroqi ◽

Natasha N. DeMeo ◽

Pamela J. McLean

Keyword(s):

Parkinson Disease ◽

Mitochondrial Dysfunction ◽

Mitochondrial Function ◽

Mitochondrial Dynamics ◽

Lewy Body Disease ◽

Camp Response Element Binding ◽

Protective Role ◽

Alpha Synuclein ◽

Sirtuin 3

AbstractThe sirtuins are highly conserved nicotinamide adenine dinucleotide (NAD+)-dependent enzymes that play a broad role in cellular metabolism and aging. Mitochondrial sirtuin 3 (SIRT3) is downregulated in aging and age-associated diseases such as cancer and neuro-degeneration and plays a major role in maintaining mitochondrial function and preventing oxidative stress. Mitochondria dysfunction is central to the pathogenesis of Parkinson disease with mutations in mitochondrial-associated proteins such as PINK1 and parkin causing familial Parkinson disease. Here, we demonstrate that the presence of alpha-synuclein (αsyn) oligomers in mitochondria induce a corresponding decrease in mitochondrial SIRT3 activity and decreased mitochondrial biogenesis. We show that SIRT3 downregulation in the presence of αsyn accumulation is accompanied by increased phosphorylation of AMP-activated protein kinase (AMPK) and cAMP-response element binding protein (CREB), as well as increased phosphorylation of dynamin-related protein 1 (DRP1) and decreased levels of optic atrophy 1 (OPA1), which is indicative of impaired mitochondrial dynamics. Treatment with the AMPK agonist 5-aminoimidazole-4-carboxamide-1-β-d-ribofuranoside (AICAR) restores SIRT3 expression and activity and improves mitochondrial function by decreasing αsyn oligomer formation. The accumulation of αsyn oligomers in mitochondria corresponds with SIRT3 down-regulation not only in an experimental cellular model, but also in vivo in a rodent model of Parkinson disease, and importantly, in human post mortem brains with neuropathologically confirmed Lewy body disease (LBD). Taken together our findings suggest that pharmacologically increasing SIRT3 levels will counteract αsyn-induced mitochondrial dysfunction by normalizing mitochondrial bioenergetics. These data support a protective role for SIRT3 in Parkinson disease-associated pathways and reveals significant mechanistic insight into the interplay of SIRT3 and αsyn.

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Training Enhances Immune Cells Mitochondrial Biosynthesis, Fission, Fusion, and Their Antioxidant Capabilities Synergistically with Dietary Docosahexaenoic Supplementation

Oxidative Medicine and Cellular Longevity ◽

10.1155/2016/8950384 ◽

2016 ◽

Vol 2016 ◽

pp. 1-10 ◽

Cited By ~ 14

Author(s):

Carla Busquets-Cortés ◽

Xavier Capó ◽

Miquel Martorell ◽

Josep A. Tur ◽

Antoni Sureda ◽

...

Keyword(s):

Mitochondrial Function ◽

Mononuclear Cells ◽

Mitochondrial Dynamics ◽

Nutritional Intervention ◽

Membrane Lipid ◽

Erythrocyte Membranes ◽

Omega 3 ◽

Double Blind ◽

Peripheral Blood Mononuclear ◽

Protein Levels

Exercise training induces adaptations in mitochondrial metabolism, dynamics, and oxidative protection. Omega-3 fatty acids change membrane lipid composition and modulate mitochondrial function. The aim was to investigate the effect of 8-week training and docosahexaenoic acid (DHA) supplementation (1.14 g/day) on the mitochondria dynamics and antioxidant status in peripheral blood mononuclear cells (PBMCs) from sportsmen. Subjects were assigned to an intervention (N=9) or placebo groups (N=7) in a randomized double-blind trial. Nutritional intervention significantly increased the DHA content in erythrocyte membranes from the experimental group. No significant differences were reported in terms of circulating PBMCs, Mn-superoxide dismutase protein levels, and their capability to produce reactive oxygen species. The proteins related to mitochondrial dynamics were, in general, increased after an 8-week training and this increase was enhanced by DHA supplementation. The content in mitofusins Mtf-1 and Mtf-2, optic atrophy protein-1 (Opa-1), and mitochondrial transcription factor A (Tfam) were significantly higher in the DHA-supplemented group after intervention. Cytochrome c oxidase (COX-IV) activity and uncoupling proteins UCP-2 and UCP-3 protein levels were increased after training, with higher UCP-3 levels in the supplemented group. In conclusion, training induced mitochondrial adaptations which may contribute to improved mitochondrial function. This mitochondrial response was modulated by DHA supplementation.

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Squamosamide Derivative FLZ Diminishes Aberrant Mitochondrial Fission by Inhibiting Dynamin-Related Protein 1

Frontiers in Pharmacology ◽

10.3389/fphar.2021.588003 ◽

2021 ◽

Vol 12 ◽

Author(s):

Hanyu Yang ◽

Lu Wang ◽

Caixia Zang ◽

Xu Yang ◽

Xiuqi Bao ◽

...

Keyword(s):

Mitochondrial Dysfunction ◽

Dopaminergic Neurons ◽

Motor Coordination ◽

Mitochondrial Dynamics ◽

Mitochondrial Fission ◽

Mitochondrial Morphology ◽

Protective Effects ◽

Related Protein ◽

Mitochondrial Fragmentation

Mitochondrial dysfunction is involved in the pathogenesis of Parkinson’s disease (PD). Mitochondrial morphology is dynamic and precisely regulated by mitochondrial fission and fusion machinery. Aberrant mitochondrial fragmentation, which can result in cell death, is controlled by the mitochondrial fission protein, dynamin-related protein 1 (Drp1). Our previous results demonstrated that FLZ could correct mitochondrial dysfunction, but the effect of FLZ on mitochondrial dynamics remain uncharacterized. In this study, we investigated the effect of FLZ and the role of Drp1 on 1-methyl-4-phenylpyridinium (MPP+)–induced mitochondrial fission in neurons. We observed that FLZ blocked Drp1, inhibited Drp1 enzyme activity, and reduced excessive mitochondrial fission in cultured neurons. Furthermore, by inhibiting mitochondrial fission and ROS production, FLZ improved mitochondrial integrity and membrane potential, resulting in neuroprotection. FLZ curtailed the reduction of synaptic branches of primary cultured dopaminergic neurons caused by MPP+ exposure, reduced abnormal fission, restored normal mitochondrial distribution in neurons, and exhibited protective effects on dopaminergic neurons. The in vitro research results were validated using an MPTP-induced PD mouse model. The in vivo results revealed that FLZ significantly reduced the mitochondrial translocation of Drp1 in the midbrain of PD mice, which, in turn, reduced the mitochondrial fragmentation in mouse substantia nigra neurons. FLZ also protected dopaminergic neurons in PD mice and increased the dopamine content in the striatum, which improved the motor coordination ability of the mice. These findings elucidate this newly discovered mechanism through which FLZ produces neuroprotection in PD.

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