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International Journal of Molecular... Sep 2023Mitochondria are involved in the regulation of cellular energy metabolism, calcium homeostasis, and apoptosis. For mitochondrial quality control, dynamic processes, such... (Review)
Review
Mitochondria are involved in the regulation of cellular energy metabolism, calcium homeostasis, and apoptosis. For mitochondrial quality control, dynamic processes, such as mitochondrial fission and fusion, are necessary to maintain shape and function. Disturbances of mitochondrial dynamics lead to dysfunctional mitochondria, which contribute to the development and progression of numerous diseases, including Type 2 Diabetes (T2D). Compelling evidence has been put forward that mitochondrial dynamics play a significant role in the metabolism-secretion coupling of pancreatic β cells. The disruption of mitochondrial dynamics is linked to defects in energy production and increased apoptosis, ultimately impairing insulin secretion and β cell death. This review provides an overview of molecular mechanisms controlling mitochondrial dynamics, their dysfunction in pancreatic β cells, and pharmaceutical agents targeting mitochondrial dynamic proteins, such as mitochondrial division inhibitor-1 (mdivi-1), dynasore, P110, and 15-oxospiramilactone (S3).
Topics: Humans; Insulin Secretion; Diabetes Mellitus, Type 2; Mitochondrial Dynamics; Apoptosis; Mitochondrial Proteins
PubMed: 37762083
DOI: 10.3390/ijms241813782 -
Molecular Oncology Aug 2021Despite recent progress in non-small-cell lung cancer (NSCLC) treatment, treatment outcomes remain poor, mainly because of treatment resistance or toxicity. Erastin is a...
Despite recent progress in non-small-cell lung cancer (NSCLC) treatment, treatment outcomes remain poor, mainly because of treatment resistance or toxicity. Erastin is a ferroptosis inducer that has shown promising cytotoxic effects in various types of cancers, including NSCLC. Celastrol is a triterpene extracted from the Tripterygium wilfordii that exhibits potential anticancer activity. However, the side effects of celastrol are severe and limit its clinical application. Combination therapy is a promising strategy to overcome the compensatory mechanisms and unwanted off-target effects. In the present study, we found that erastin synergized with celastrol to induce cell death at nontoxic concentrations. The combined treatment with celastrol and erastin significantly increased reactive oxygen species (ROS) generation, disrupted mitochondrial membrane potential, and promoted mitochondrial fission. Furthermore, cotreatment with erastin and celastrol initiated ATG5/ATG7-dependent autophagy, PINK1/Parkin-dependent mitophagy, and the expression of heat shock proteins (HSPs) in an HSF1-dependent manner. HSF1 knockdown further enhanced cell death in vitro and inhibited tumor growth in vivo. Our findings indicate that the combination of celastrol with erastin may represent a novel therapeutic regimen for patients with NSCLC and warrants further clinical evaluation.
Topics: Animals; Carcinoma, Non-Small-Cell Lung; Cell Line, Tumor; Female; Ferroptosis; Humans; Lung Neoplasms; Mice; Mice, Inbred BALB C; Mitochondrial Dynamics; Mitophagy; Pentacyclic Triterpenes; Piperazines; Reactive Oxygen Species; Xenograft Model Antitumor Assays
PubMed: 33675143
DOI: 10.1002/1878-0261.12936 -
Scientific Reports Apr 2024Mitochondria, the powerhouse and the vital signaling hub of the cell, participate in a variety of biological processes, such as apoptosis, redox responses, cell...
Mitochondria, the powerhouse and the vital signaling hub of the cell, participate in a variety of biological processes, such as apoptosis, redox responses, cell senescence, autophagy, and iron homeostasis. Mitochondria form a mostly tubular network, made up of an outer and a cristeae-forming inner membrane. The network undergoes dynamic fusion and fission that change its morphological structure according to the functional needs. Approximately 1500 mitochondrial proteins encoded by nuclear genome plus over 10 proteins encoded by mitochondrial DNA are folded and assembled in the mitochondria under a high-fidelity control system. These proteins are involved in oxidative phosphorylation, metabolism, network and cristae dynamics, mitophagy, import machinery, ion channels, and mitochondrial DNA maintenance. This Collection gathers original research that advances our understanding of the monitoring techniques and pathophysiological significance of mitochondrial dynamics in health and disease.
Topics: Mitochondrial Dynamics; Humans; Mitochondria; Animals
PubMed: 38688939
DOI: 10.1038/s41598-024-59998-1 -
Journal of Cell Science Jul 2020Mitochondrial fusion and fission (mitochondrial dynamics) are homeostatic processes that safeguard normal cellular function. This relationship is especially strong in... (Review)
Review
Mitochondrial fusion and fission (mitochondrial dynamics) are homeostatic processes that safeguard normal cellular function. This relationship is especially strong in tissues with constitutively high energy demands, such as brain, heart and skeletal muscle. Less is known about the role of mitochondrial dynamics in developmental systems that involve changes in metabolic function. One such system is spermatogenesis. The first mitochondrial dynamics gene, (), was discovered in 1997 to mediate mitochondrial fusion during spermatogenesis. In mammals, however, the role of mitochondrial fusion during spermatogenesis remained unknown for nearly two decades after discovery of Mammalian spermatogenesis is one of the most complex and lengthy differentiation processes in biology, transforming spermatogonial stem cells into highly specialized sperm cells over a 5-week period. This elaborate differentiation process requires several developmentally regulated mitochondrial and metabolic transitions, making it an attractive model system for studying mitochondrial dynamics We review the emerging role of mitochondrial biology, and especially its dynamics, during the development of the male germ line.
Topics: Animals; Drosophila; Drosophila Proteins; Male; Mitochondria; Mitochondrial Dynamics; Spermatogenesis
PubMed: 32675215
DOI: 10.1242/jcs.235937 -
Journal of Translational Medicine Mar 2023Necroptosis of macrophages is a necessary element in reinforcing intrapulmonary inflammation during acute lung injury (ALI). However, the molecular mechanism that sparks...
BACKGROUND
Necroptosis of macrophages is a necessary element in reinforcing intrapulmonary inflammation during acute lung injury (ALI). However, the molecular mechanism that sparks macrophage necroptosis is still unclear. Triggering receptor expressed on myeloid cells-1 (TREM-1) is a pattern recognition receptor expressed broadly on monocytes/macrophages. The influence of TREM-1 on the destiny of macrophages in ALI requires further investigation.
METHODS
TREM-1 decoy receptor LR12 was used to evaluate whether the TREM-1 activation induced necroptosis of macrophages in lipopolysaccharide (LPS)-induced ALI in mice. Then we used an agonist anti-TREM-1 Ab (Mab1187) to activate TREM-1 in vitro. Macrophages were treated with GSK872 (a RIPK3 inhibitor), Mdivi-1 (a DRP1 inhibitor), or Rapamycin (an mTOR inhibitor) to investigate whether TREM-1 could induce necroptosis in macrophages, and the mechanism of this process.
RESULTS
We first observed that the blockade of TREM-1 attenuated alveolar macrophage (AlvMs) necroptosis in mice with LPS-induced ALI. In vitro, TREM-1 activation induced necroptosis of macrophages. mTOR has been previously linked to macrophage polarization and migration. We discovered that mTOR had a previously unrecognized function in modulating TREM-1-mediated mitochondrial fission, mitophagy, and necroptosis. Moreover, TREM-1 activation promoted DRP1 phosphorylation through mTOR signaling, which in turn caused surplus mitochondrial fission-mediated necroptosis of macrophages, consequently exacerbating ALI.
CONCLUSION
In this study, we reported that TREM-1 acted as a necroptotic stimulus of AlvMs, fueling inflammation and aggravating ALI. We also provided compelling evidence suggesting that mTOR-dependent mitochondrial fission is the underpinning of TREM-1-triggered necroptosis and inflammation. Therefore, regulation of necroptosis by targeting TREM-1 may provide a new therapeutic target for ALI in the future.
Topics: Animals; Mice; Triggering Receptor Expressed on Myeloid Cells-1; Lipopolysaccharides; Mitochondrial Dynamics; Necroptosis; TOR Serine-Threonine Kinases; Macrophages; Acute Lung Injury; Inflammation
PubMed: 36879273
DOI: 10.1186/s12967-023-04027-4 -
Cells Mar 2020For decades, sphingolipids have been related to several biological functions such as immune system regulation, cell survival, and proliferation. Recently, it has been... (Review)
Review
For decades, sphingolipids have been related to several biological functions such as immune system regulation, cell survival, and proliferation. Recently, it has been reported that sphingolipids could be biomarkers in cancer and in other human disorders such as metabolic diseases. This is evidenced by the biological complexity of the sphingolipids associated with cell type-specific signaling and diverse sphingolipids molecules. As mitochondria dynamics have serious implications in homeostasis, in the present review, we focused on the relationship between sphingolipids, mainly ceramides and sphingosine-1-phosphate, and mitochondrial dynamics directed by fission, fusion, and mitophagy. There is evidence that the balances of ceramides (C18 and C16) and S1P, as well as the location of specific ceramide synthases in mitochondria, have roles in mitophagy and fission with an impact on cell fate and metabolism. However, signaling pathways controlling the sphingolipids metabolism and their location in mitochondria need to be better understood in order to propose new interventions and therapeutic strategies.
Topics: Humans; Mitochondrial Dynamics; Signal Transduction; Sphingolipids
PubMed: 32121501
DOI: 10.3390/cells9030581 -
Autophagy Apr 2024Intervertebral disc degeneration (IDD) is the most critical pathological factor in the development of low back pain. The maintenance of nucleus pulposus (NP) cell and...
Intervertebral disc degeneration (IDD) is the most critical pathological factor in the development of low back pain. The maintenance of nucleus pulposus (NP) cell and intervertebral disc integrity benefits largely from well-controlled mitochondrial quality, surveilled by mitochondrial dynamics (fission and fusion) and mitophagy, but the outcome is cellular context-dependent that remain to be clarified. Our studies revealed that the loss of NLRX1 is correlated with NP cell senescence and IDD progression, which involve disordered mitochondrial quality. Further using animal and in vitro tissue and cell models, we demonstrated that NLRX1 could facilitate mitochondrial quality by coupling mitochondrial dynamic factors (p-DNM1L, L-OPA1:S-OPA1, OMA1) and mitophagy activity. Conversely, mitochondrial collapse occurred in NLRX1-defective NP cells and switched on the compensatory PINK1-PRKN pathway that led to excessive mitophagy and aggressive NP cell senescence. Mechanistically, NLRX1 was originally shown to interact with zinc transporter SLC39A7 and modulate mitochondrial Zn trafficking via the formation of an NLRX1-SLC39A7 complex on the mitochondrial membrane of NP cells, subsequently orchestrating mitochondrial dynamics and mitophagy. The restoration of NLRX1 function by gene overexpression or pharmacological agonist (NX-13) treatment showed great potential for regulating mitochondrial fission with synchronous fusion and mitophagy, thus sustaining mitochondrial homeostasis, ameliorating NP cell senescence and rejuvenating intervertebral discs. Collectively, our findings highlight a working model whereby the NLRX1-SLC39A7 complex coupled mitochondrial dynamics and mitophagy activity to surveil and target damaged mitochondria for degradation, which determines the beneficial function of the mitochondrial surveillance system and ultimately rejuvenates intervertebral discs. 3-MA: 3-methyladenine; Baf-A: bafilomycin A; CDKN1A/p21: cyclin dependent kinase inhibitor 1A; CDKN2A/p16: cyclin dependent kinase inhibitor 2A; DNM1L/DRP1: dynamin 1 like; EdU: 5-Ethynyl-2'-deoxyuridine; HE: hematoxylin-eosin; IDD: intervertebral disc degeneration; IL1B/IL-1β: interleukin 1 beta; IL6: interleukin 6; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; MKI67/Ki67: marker of proliferation Ki-67; LBP: low back pain; MMP: mitochondrial membrane potential; MFN1: mitofusin 1; MFN2: mitofusin 2; MFF: mitochondrial fission factor; NP: nucleus pulposus; NLRX1: NLR family member X1; OMA1: OMA1 zinc metallopeptidase; OPA1: OPA1 mitochondrial dynamin like GTPase; PINK1: PTEN induced kinase 1; PRKN: parkin RBR E3 ubiquitin protein ligase; ROS: reactive oxidative species; SASP: senescence-associated secretory phenotype; SA-GLB1/β-gal: senescence-associated galactosidase beta 1; SO: safranin o; TBHP: tert-butyl hydroperoxide; TP53/p53: tumor protein p53; SLC39A7/ZIP7: solute carrier family 39 member 7; TOMM20: translocase of outer mitochondrial membrane 20; TIMM23: translocase of inner mitochondrial membrane 23.
Topics: Mitophagy; Mitochondrial Dynamics; Mitochondria; Animals; Zinc; Intervertebral Disc Degeneration; Mitochondrial Proteins; Cellular Senescence; Nucleus Pulposus; Humans; Intervertebral Disc; Cation Transport Proteins; Mice; Protein Kinases
PubMed: 37876250
DOI: 10.1080/15548627.2023.2274205 -
International Journal of Molecular... Jan 2022Biological sex influences disease development and progression. The steroid hormone 17β-oestradiol (E2), along with its receptors, is expected to play a major role in... (Review)
Review
Biological sex influences disease development and progression. The steroid hormone 17β-oestradiol (E2), along with its receptors, is expected to play a major role in the manifestation of sex differences. E2 exerts pleiotropic effects in a system-specific manner. Mitochondria are one of the central targets of E2, and their biogenesis and respiration are known to be modulated by E2. More recently, it has become apparent that E2 also regulates mitochondrial fusion-fission dynamics, thereby affecting cellular metabolism. The aim of this article is to discuss the regulatory pathways by which E2 orchestrates the activity of several components of mitochondrial dynamics in the cardiovascular and nervous systems in health and disease. We conclude that E2 regulates mitochondrial dynamics to maintain the mitochondrial network promoting mitochondrial fusion and attenuating mitochondrial fission in both the cardiovascular and nervous systems.
Topics: Animals; Cardiovascular System; Estradiol; Female; Gene Expression Regulation; Humans; Male; Mitochondria; Mitochondrial Dynamics; Nervous System; Receptors, Estrogen; Sex Characteristics
PubMed: 35163044
DOI: 10.3390/ijms23031118 -
Nutrients May 2023The bone synthesizing function of osteoblasts (OBs) is a highly demanding energy process that requires nutrients. However, how nutrient availability affects OBs behavior...
BACKGROUND
The bone synthesizing function of osteoblasts (OBs) is a highly demanding energy process that requires nutrients. However, how nutrient availability affects OBs behavior and bone mineralization remain to be fully understood.
METHODS
MC3T3-E1 cell line and primary OBs (OBs) cultures were treated with physiological levels of glucose (G; 5.5 mM) alone or with the addition of palmitic acid (G+PA) at different concentrations. Mitochondria morphology and activity were evaluated by fluorescence microscopy, qPCR, and oxygen consumption rate (OCR) measurement, and OBs function was assessed by mineralization assay.
RESULTS
The addition of non-lipotoxic levels of 25 μM PA to G increased mineralization in OBs. G+25 μM PA exposure reduced mitochondria size in OBs, which was associated with increased activation of dynamin-related protein 1, a mitochondrial fission protein, enhanced mitochondria OCR and ATP production, and increased expression of oxidative phosphorylation genes. Treatment with Mdivi-1, a putative inhibitor of mitochondrial fission, reduced osteogenesis and mitochondrial respiration in OBs.
CONCLUSIONS
Our results revealed that OBs function was enhanced in the presence of glucose and PA at 25 μM. This was associated with increased OBs mitochondrial respiration and dynamics. These results suggest a role for nutrient availability in bone physiology and pathophysiology.
Topics: Mitochondrial Dynamics; Glucose; Mitochondrial Proteins; Nutrients; Osteoblasts
PubMed: 37432387
DOI: 10.3390/nu15092222 -
International Journal of Molecular... Apr 2021Mitochondria are important organelles involved in metabolism and programmed cell death in eukaryotic cells. In addition, mitochondria are also closely related to the... (Review)
Review
Mitochondria are important organelles involved in metabolism and programmed cell death in eukaryotic cells. In addition, mitochondria are also closely related to the innate immunity of host cells against viruses. The abnormality of mitochondrial morphology and function might lead to a variety of diseases. A large number of studies have found that a variety of viral infections could change mitochondrial dynamics, mediate mitochondria-induced cell death, and alter the mitochondrial metabolic status and cellular innate immune response to maintain intracellular survival. Meanwhile, mitochondria can also play an antiviral role during viral infection, thereby protecting the host. Therefore, mitochondria play an important role in the interaction between the host and the virus. Herein, we summarize how viral infections affect microbial pathogenesis by altering mitochondrial morphology and function and how viruses escape the host immune response.
Topics: Animals; Humans; Immunity, Cellular; Immunity, Innate; Mitochondria; Mitochondrial Dynamics
PubMed: 33923929
DOI: 10.3390/ijms22084260