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1.
J Ethnopharmacol ; 301: 115784, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36206870

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Taohong Siwu Decoction (THSWD) is a traditional Chinese medicine formula used to invigorate blood circulation and resolve blood stasis. It consists of Paeonia lactiflora Pall., Conioselinum anthriscoides (H.Boissieu) Pimenov & Kljuykov, Rehmannia glutinosa (Gaertn.) DC., Prunus persica (L.) Batsch, Angelica sinensis (Oliv.) Diels, and Carthamus creticus L. in the ratio of 3:2:4:3:3:2. THSWD is a common prescription for the treatment of ischemic stroke. AIM OF THE STUDY: To study the protective effect and mechanism of Taohong Siwu Decoction (THSWD) on PC12 cells damaged by oxygen glucose deprivation/reperfusion (OGD/R). MATERIALS AND METHODS: OGD/R model of PC12 cells was used to simulate ischemia-reperfusion (I/R) injury of nerve cells in vitro. The experiment was grouped as follows: control, OGD/R and OGD/R + THSWD (5%, 10% and 15%) group. Oxygen and glucose was restored for 24 h after 4-6 h of deprivation. The severity of damage to PC12 cells was evaluated by CCK8, flow cytometry and lactate dehydrogenase (LDH). Mitochondrial morphology and function were examined by transmission electron microscopy (TEM), ATP and mitochondrial membrane potential (MMP) assay kits. Cellular autophagy and NLRP3 inflammasome-associated proteins were detected by Western blot and immunofluorescence staining. RESULTS: THSWD treatment improved the survival rate of PC12 cells injured by OGD/R, reduced cell damage and apoptosis. Moreover, ATP, MMP and the expression of autophagy marker proteins (LC3-II/LC3-I, Beclin1, Atg5) and mitophagy marker proteins (Parkin and PINK-1) was significantly elevated. The reactive oxygen species (ROS), NLRP3 inflammasome and pro-inflammatory cytokines induced by OGD/R were distinctly reduced. In contrast, these above beneficial effects of THSWD on mitochondrial autophagy and NLRP3 inflammasome were reversed by mitochondrial division inhibitory factor 1 (Mdivi-1). CONCLUSION: THSWD protects PC12 cells against OGD/R injury by heightening mitophagy and suppressing the activation of NLRP3 inflammasome.


Assuntos
Inflamassomos , Traumatismo por Reperfusão , Ratos , Animais , Células PC12 , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Glucose/metabolismo , Mitofagia , Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Apoptose , Reperfusão , Trifosfato de Adenosina
2.
Toxicol Lett ; 372: 14-24, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36273635

RESUMO

The pathophysiology of renal lipid toxicity caused by excess adiposity is not well-understood. Necroptosis, a regulated form of cell death, is involved in injuring renal tubular epithelial cells (RTECs). Phosphoglycerate mutase 5 (PGAM5) is a key downstream effector of necroptosis. This study investigated the underlying mechanism of PGAM5 in promoting lipid-induced necroptosis in RTECs. HK2 cells (an immortalized proximal tubule epithelial cell line) were exposed to oleic acid (OA) to mimic the lipid overload environment in vitro. We found that OA suppressed HK2 cell proliferation, triggered cytoskeleton rupture and cell death. In OA-treated cells, upregulated expression of necroptosis pathway proteins, phosphorylated receptor-interacting protein-1/3 (pRIPK1/3), phosphorylated mixed lineage kinase domain-like protein (pMLKL), PGAM5, phosphorylated dynamin-related protein 1 (pDRP1S616), and downregulated pDRP1S637 expression were observed. This was accompanied by mitochondrial dysfunction (mitochondrial ROS overproduction and decreased mitochondrial membrane potential) and increased cellular necrosis, as reflected by Annexin V/ Propidium Iodide (PI) labeling. OA also induced the accumulation of LC3II and P62, blocking autophagosome fusion with lysosomes. Knockdown of PGAM5 could prevent these OA-induced changes. We propose inhibition of PGAM5 protects lipid-induced RTECs from necroptosis by reducing DRP1-mediated mitochondrial fission and improving mitophagy flux.


Assuntos
Dinâmica Mitocondrial , Mitofagia , Necroptose , Fosfoglicerato Mutase/metabolismo , Células Epiteliais/metabolismo , Lipídeos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo
3.
Cell Metab ; 34(11): 1809-1823.e6, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36323236

RESUMO

Mitochondria have their own DNA (mtDNA), which is susceptible to the accumulation of disease-causing mutations. To prevent deleterious mutations from being inherited, the female germline has evolved a conserved quality control mechanism that remains poorly understood. Here, through a large-scale screen, we uncover a unique programmed germline mitophagy (PGM) that is essential for mtDNA quality control. We find that PGM is developmentally triggered as germ cells enter meiosis by inhibition of the target of rapamycin complex 1 (TORC1). We identify a role for the RNA-binding protein Ataxin-2 (Atx2) in coordinating the timing of PGM with meiosis. We show that PGM requires the mitophagy receptor BNIP3, mitochondrial fission and translation factors, and members of the Atg1 complex, but not the mitophagy factors PINK1 and Parkin. Additionally, we report several factors that are critical for germline mtDNA quality control and show that pharmacological manipulation of one of these factors promotes mtDNA quality control.


Assuntos
DNA Mitocondrial , Mitofagia , Mitofagia/genética , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Mitocôndrias/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Células Germinativas/metabolismo , Controle de Qualidade
4.
Cell Death Dis ; 13(11): 928, 2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36335091

RESUMO

Cadmium is one of the environmental and occupational pollutants and its potential adverse effects on human health have given rise to substantial concern. Cadmium causes damage to the male reproductive system via induction of germ-cell apoptosis; however, the underlying mechanism of cadmium-induced reproductive toxicity in Leydig cells remains unclear. In this study, twenty mice were divided randomly into four groups and exposed to CdCl2 at concentrations of 0, 0.5, 1.0 and 2.0 mg/kg/day for four consecutive weeks. Testicular injury, abnormal spermatogenesis and apoptosis of Leydig cells were observed in mice. In order to investigate the mechanism of cadmium-induced apoptosis of Leydig cells, a model of mouse Leydig cell line (i.e. TM3 cells) was subjected to treatment with various concentrations of CdCl2. It was found that mitochondrial function was disrupted by cadmium, which also caused a significant elevation in levels of mitochondrial superoxide and cellular ROS. Furthermore, while cadmium increased the expression of mitochondrial fission proteins (DRP1 and FIS1), it reduced the expression of mitochondrial fusion proteins (OPA1 and MFN1). This led to excessive mitochondrial fission, the release of cytochrome c and apoptosis. Conversely, cadmium-induced accumulation of mitochondrial superoxide was decreased by the inhibition of mitochondrial fission through the use of Mdivi-1 (an inhibitor of DRP1). Mdivi-1 also partially prevented the release of cytochrome c from mitochondria to cytosol and attenuated cell apoptosis. Finally, given the accumulation of LC3II and SQSTM1/p62 and the obstruction of Parkin recruitment into damaged mitochondria in TM3 cells, the autophagosome-lysosome fusion was probably inhibited by cadmium. Overall, these findings suggest that cadmium induces apoptosis of mouse Leydig cells via the induction of excessive mitochondrial fission and inhibition of mitophagy.


Assuntos
Dinâmica Mitocondrial , Mitofagia , Animais , Masculino , Camundongos , Apoptose , Cádmio/toxicidade , Citocromos c , Células Intersticiais do Testículo/metabolismo , Proteínas Mitocondriais/metabolismo , Superóxidos
5.
Immunity ; 55(11): 2059-2073.e8, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36351375

RESUMO

T memory stem cells (TSCM) display increased self-renewal and prolonged survival capabilities, thus preventing T cell exhaustion and promoting effective anti-tumor T cell responses. TSCM cells can be expanded by Urolithin A (UA), which is produced by the commensal gut microbiome from foods rich in ellagitannins and is known to improve mitochondrial health. Oral UA administration to tumor-bearing mice conferred strong anti-tumor CD8+ T cell immunity, whereas ex vivo UA pre-treated T cells displayed improved anti-tumor function upon adoptive cell transfer. UA-induced TSCM formation depended on Pink1-mediated mitophagy triggering cytosolic release of the mitochondrial phosphatase Pgam5. Cytosolic Pgam5 dephosphorylated ß-catenin, which drove Wnt signaling and compensatory mitochondrial biogenesis. Collectively, we unravel a critical signaling pathway linking mitophagy to TSCM formation and suggest that the well-tolerated metabolic compound UA represents an attractive option to improve immune therapy.


Assuntos
Cumarínicos , Mitofagia , Camundongos , Animais , Cumarínicos/farmacologia , Via de Sinalização Wnt , Células-Tronco , Memória Imunológica
6.
Cell Death Dis ; 13(11): 947, 2022 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-36357363

RESUMO

Autophagy is an evolutionarily conserved eukaryotic cellular mechanism through which cytosolic fragments, misfolded/aggregated proteins and organelles are degraded and recycled. Priming of mitochondria through ubiquitylation is required for the clearance the organelle by autophagy (mitophagy). Familial Parkinson's Disease-related proteins, including the E3-ligase PARK2 (PARKIN) and the serine/threonine kinase PARK6 (PINK1) control these ubiquitylation reactions and contribute to the regulation of mitophagy. Here we describe, novel protein complexes containing autophagy protein ATG5 and ubiquitin-proteasome system (UPS) components. We discovered that ATG5 interacts with PSMA7 and PARK2 upon mitochondrial stress. Results suggest that all three proteins translocate mitochondria and involve in protein complexes containing autophagy, UPS and mitophagy proteins. Interestingly, PARK2 and ATG5 recruitment onto mitochondria requires proteasome components PSMA7 and PSMB5. Strikingly, we discovered that subunit of 20 S proteasome, PSMA7, is required for the progression of PARK2-PARK6-mediated mitophagy and the proteasome activity following mitochondrial stress. Our results demonstrate direct, dynamic and functional interactions between autophagy and UPS components that contribute to the regulation of mitophagy.


Assuntos
Mitofagia , Doença de Parkinson , Humanos , Mitofagia/fisiologia , Ubiquitina/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Doença de Parkinson/metabolismo , Mitocôndrias/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Autofagia/fisiologia
7.
Int J Mol Sci ; 23(21)2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36361713

RESUMO

Mitochondria are an important energy source in skeletal muscle. A main function of mitochondria is the generation of ATP for energy through oxidative phosphorylation (OXPHOS). Mitochondrial defects or abnormalities can lead to muscle disease or multisystem disease. Mitochondrial dysfunction can be caused by defective mitochondrial OXPHOS, mtDNA mutations, Ca2+ imbalances, mitochondrial-related proteins, mitochondrial chaperone proteins, and ultrastructural defects. In addition, an imbalance between mitochondrial fusion and fission, lysosomal dysfunction due to insufficient biosynthesis, and/or defects in mitophagy can result in mitochondrial damage. In this review, we explore the association between impaired mitochondrial function and skeletal muscle disorders. Furthermore, we emphasize the need for more research to determine the specific clinical benefits of mitochondrial therapy in the treatment of skeletal muscle disorders.


Assuntos
Mitocôndrias , Doenças Musculares , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Fosforilação Oxidativa , Mitofagia , Dinâmica Mitocondrial , Doenças Musculares/metabolismo , Músculo Esquelético/metabolismo , Proteínas Mitocondriais/metabolismo , DNA Mitocondrial/genética
8.
Invest Ophthalmol Vis Sci ; 63(12): 18, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36374514

RESUMO

Purpose: To assess the role of mitochondrial morphology and adenosine monophosphate-activated protein kinase (AMPK)/mitochondrial fission factor (MFF) in dry eye and the underlying mechanisms. Methods: Immortalized human corneal epithelial cells (HCECs) and primary HCECs were cultured under high osmotic pressure (HOP). C57BL/6 female mice were injected subcutaneously with scopolamine. Quantitative real-time PCR was used to measure mRNA expression. Protein expression was assessed by western blot and immunofluorescence staining. Mitochondrial morphology was observed by confocal microscopy and transmission electron microscopy. Results: First, HOP induced mitochondrial oxidative damage to HCECs, accompanied by mitochondrial fission and increased mitophagy. Then, AMPK/MFF pathway proteins were increased consequent to HOP-induced energy metabolism dysfunction. Interestingly, the AMPK pathway promoted mitochondrial fission and mitophagy by increasing the recruitment of dynamin-related protein 1 (DRP1) to the mitochondrial outer membrane in the HOP group. Moreover, AMPK knockdown attenuated mitochondrial fission and mitophagy due to HOP in HCECs. AMPK activation triggered mitochondrial fission and mitophagy. Mitochondrial fission of HCECs stressed by HOP was mediated via MFF phosphorylation. MFF knockdown reversed mitochondrial fragmentation and mitophagy in HCECs treated with HOP. Inhibition of MFF protected HCECs against oxidative damage, cell death, and inflammation in the presence of HOP. Finally, we detected mitochondrial fission and AMPK pathway activation in vivo. Conclusions: The AMPK/MFF pathway mediates the development of dry eye by positively regulating mitochondrial fission and mitophagy. Inhibition of mitochondrial fission can alleviate oxidative damage and inflammation in dry eye and may provide experimental evidence for treating dry eye.


Assuntos
Síndromes do Olho Seco , Dinâmica Mitocondrial , Feminino , Humanos , Camundongos , Animais , Dinâmica Mitocondrial/genética , Mitofagia , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Mitocondriais/genética , Camundongos Endogâmicos C57BL , Inflamação , Proteínas de Membrana
9.
Cell Death Dis ; 13(11): 976, 2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36402748

RESUMO

Embryonic stem cells (ESCs) have a significantly lower mutation load compared to somatic cells, but the mechanisms that guard genomic integrity in ESCs remain largely unknown. Here we show that BNIP3-dependent mitophagy protects genomic integrity in mouse ESCs. Deletion of Bnip3 increases cellular reactive oxygen species (ROS) and decreases ATP generation. Increased ROS in Bnip3-/- ESCs compromised self-renewal and were partially rescued by either NAC treatment or p53 depletion. The decreased cellular ATP in Bnip3-/- ESCs induced AMPK activation and deteriorated homologous recombination, leading to elevated mutation load during long-term propagation. Whereas activation of AMPK in X-ray-treated Bnip3+/+ ESCs dramatically ascended mutation rates, inactivation of AMPK in Bnip3-/- ESCs under X-ray stress remarkably decreased the mutation load. In addition, enhancement of BNIP3-dependent mitophagy during reprogramming markedly decreased mutation accumulation in established iPSCs. In conclusion, we demonstrated a novel pathway in which BNIP3-dependent mitophagy safeguards ESC genomic stability, and that could potentially be targeted to improve pluripotent stem cell genomic integrity for regenerative medicine.


Assuntos
Proteínas Quinases Ativadas por AMP , Mitofagia , Camundongos , Animais , Mitofagia/genética , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Estresse Oxidativo , Genômica , Recombinação Homóloga , Dano ao DNA/genética , Trifosfato de Adenosina/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo
10.
Nat Commun ; 13(1): 6661, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333379

RESUMO

Parkin, an E3 ubiquitin ligase, plays an essential role in mitochondrial quality control. However, the mechanisms by which Parkin connects mitochondrial homeostasis with cellular metabolism in adipose tissue remain unclear. Here, we demonstrate that Park2 gene (encodes Parkin) deletion specifically from adipose tissue protects mice against high-fat diet and aging-induced obesity. Despite a mild reduction in mitophagy, mitochondrial DNA content and mitochondrial function are increased in Park2 deficient white adipocytes. Moreover, Park2 gene deletion elevates mitochondrial biogenesis by increasing Pgc1α protein stability through mitochondrial superoxide-activated NAD(P)H quinone dehydrogenase 1 (Nqo1). Both in vitro and in vivo studies show that Nqo1 overexpression elevates Pgc1α protein level and mitochondrial DNA content and enhances mitochondrial activity in mouse and human adipocytes. Taken together, our findings indicate that Parkin regulates mitochondrial homeostasis by balancing mitophagy and Pgc1α-mediated mitochondrial biogenesis in white adipocytes, suggesting a potential therapeutic target in adipocytes to combat obesity and obesity-associated disorders.


Assuntos
Mitofagia , Biogênese de Organelas , Camundongos , Humanos , Animais , Mitofagia/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Adipócitos Brancos/metabolismo , Adiposidade , Ubiquitina-Proteína Ligases/metabolismo , Obesidade/genética , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo
11.
Sci Rep ; 12(1): 18688, 2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333388

RESUMO

Colorectal cancer (CRC) is a heterogeneous disease and one of the most prevalent malignancies worldwide. Previous research has demonstrated that mitophagy is crucial to developing colorectal cancer. This study aims to examine the association between mitophagy-related genes and the prognosis of CRC patients. Gene expression profiles and clinical information of CRC patients were obtained from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Univariate Cox regression and the least absolute shrinkage and selection operator (LASSO) regression analysis were applied to establish a prognostic signature using mitophagy related genes. Kaplan-Meier and receiver operating characteristic (ROC) curves were used to analyze patient survival and predictive accuracy. Meanwhile, we also used the Genomics of Drug Sensitivity in Cancer (GDSC) database and Tumor Immune Dysfunction and Exclusion (TIDE) algorithm to estimate the sensitivity of chemotherapy, targeted therapy and immunotherapy. ATG14 overexpression plasmid was used to regulate the ATG14 expression level in HCT116 and SW480 cell lines, and cell counting kit-8, colony formation and transwell migration assay were performed to validate the function of ATG14 in CRC cells. A total of 22 mitophagy-driven genes connected with CRC survival were identified, and then a novel prognostic signature was established based on 10 of them (AMBRA1, ATG14, MAP1LC3A, MAP1LC3B, OPTN, VDAC1, ATG5, CSNK2A2, MFN1, TOMM22). Patients were divided into high-risk and low-risk groups based on the median risk score, and the survival of patients in the high-risk group was significantly shorter in both the training cohort and two independent cohorts. ROC curve showed that the area under the curves (AUC) of 1-, 3- and 5-year survival were 0.66, 0.66 and 0.64, respectively. Multivariate Cox regression analysis confirmed the independent prognostic value of the signature. Then we constructed a Nomogram combining the risk score, age and M stage, which had a concordance index of survival prediction of 0.77 (95% CI 0.71-0.83) and more robust predictive accuracy. Results showed that CD8+ T cells, regulatory T cells and activated NK cells were significantly more enriched in the high-risk group. Furthermore, patients in the high-risk group are more sensitive to targeted therapy or chemotherapy, including bosutinib, elesclomol, lenalidomide, midostaurin, pazopanib and sunitinib, while the low-risk group is more likely to benefit from immunotherapy. Finally, in vitro study confirmed the oncogenic significance of ATG14 in both HCT116 and SW480 cells, whose overexpression increased CRC cell proliferation, colony formation, and migration. In conclusion, we developed a novel mitophagy-related gene signature that can be utilized not only as an independent predictive biomarker but also as a tool for tailoring personalizing treatment for CRC patients, and we confirmed ATG14 as a novel oncogene in CRC.


Assuntos
Neoplasias Colorretais , Mitofagia , Humanos , Mitofagia/genética , Regulação Neoplásica da Expressão Gênica , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Estimativa de Kaplan-Meier , Neoplasias Colorretais/patologia , Prognóstico , Microambiente Tumoral/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
12.
Oxid Med Cell Longev ; 2022: 5064494, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36338340

RESUMO

Excessive generation of reactive oxygen species (ROS) has great impacts on MSU crystal-induced inflammation. Drp1-dependent mitochondrial fission is closely associated with mitochondrial ROS levels. However, whether Drp1 signaling contributes to MSU crystal-induced inflammation remains unclear. Mice bone marrow-derived macrophages (BMDMs) were primed with LPS and then stimulated with MSU suspensions for 12 h. The protein levels associated with mitochondrial dynamics, oxidative stress, and mitophagy were detected by Western blot. BMDMs were loaded with MitoTracker Green probe to detect mitochondrial morphology. To measure mitochondrial reactive oxygen species (ROS) and total ROS levels, cells were loaded, respectively, with MitoSOX and DHE probes. The effects of Mito-TEMPO, an antioxidant that targets the mitochondria or DRP1 inhibitor (Mdivi-1) on MSU crystal-induced peritonitis and arthritis mouse models, were evaluated. Our study revealed that MSU crystal stimulation resulted in elevation of mitochondrial fragmentation of BMDMs. Treatment with Mito-TEMPO or Drp1 knockdown significantly ameliorated the mitochondrial damage induced by MSU crystals. BMDMs exposure to MSU crystals increased the expression of auto/mitophagy marker proteins and promoted the fusion of mitophagosomes with lysosomes, leading to accumulation of mitolysosomes. Drp1 knockdown alleviated defective mitophagy and activation of the NLRP3 inflammasome in MSU crystal-treated BMDMs. This study indicates that there is crosstalk between mitochondrial ROS and Drp1 signaling in MSU crystal-induced inflammation. Drp1 signaling is involved in MSU crystal-induced mitochondrial damage, impaired mitophagy and NLRP3 inflammasome activation.


Assuntos
Inflamassomos , Mitofagia , Camundongos , Animais , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Dinaminas/metabolismo , Dinâmica Mitocondrial , Inflamação
13.
Nat Commun ; 13(1): 6704, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36344526

RESUMO

Understanding the mechanisms governing selective turnover of mutation-bearing mtDNA is fundamental to design therapeutic strategies against mtDNA diseases. Here, we show that specific mtDNA damage leads to an exacerbated mtDNA turnover, independent of canonical macroautophagy, but relying on lysosomal function and ATG5. Using proximity labeling and Twinkle as a nucleoid marker, we demonstrate that mtDNA damage induces membrane remodeling and endosomal recruitment in close proximity to mitochondrial nucleoid sub-compartments. Targeting of mitochondrial nucleoids is controlled by the ATAD3-SAMM50 axis, which is disrupted upon mtDNA damage. SAMM50 acts as a gatekeeper, influencing BAK clustering, controlling nucleoid release and facilitating transfer to endosomes. Here, VPS35 mediates maturation of early endosomes to late autophagy vesicles where degradation occurs. In addition, using a mouse model where mtDNA alterations cause impairment of muscle regeneration, we show that stimulation of lysosomal activity by rapamycin, selectively removes mtDNA deletions without affecting mtDNA copy number, ameliorating mitochondrial dysfunction. Taken together, our data demonstrates that upon mtDNA damage, mitochondrial nucleoids are eliminated outside the mitochondrial network through an endosomal-mitophagy pathway. With these results, we unveil the molecular players of a complex mechanism with multiple potential benefits to understand mtDNA related diseases, inherited, acquired or due to normal ageing.


Assuntos
DNA Mitocondrial , Membranas Mitocondriais , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitofagia
14.
Biomed Pharmacother ; 156: 113954, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36411638

RESUMO

Vascular aging, a major risk factor for cardiovascular disease, contributes to morbidity and mortality in older people. Mitochondria play an important role in vascular aging. In endothelial and smooth muscle cells, multiple changes in the mitochondrial structure and function contribute to aging, including the effects of mitochondrial oxidative stress, mitochondrial DNA mutations, mitochondrial dynamics, and mitophagy. Mitochondrial dysfunction also contributes to other age-related molecular and cellular mechanisms, such as crosstalk with telomeres, senescence-associated secretory phenotypes, and low-grade inflammation. Thus, enhancing mitochondrial biogenesis, reducing oxidative stress, recovering dynamics, and mitophagy have been suggested as effective interventions to delay vascular aging and age-related cardiovascular diseases. Furthermore, accumulating evidence has shown that commonly used herbs and their natural compounds have great potential to improve mitochondrial function during vascular aging. Herein, we review the cellular and molecular mechanisms of mitochondrial effects on vascular aging, emphasizing the efficacy of natural compounds in the treatment of vascular aging by improving mitochondrial structure and function. We aim to provide new insights into delaying vascular aging and preventing cardiovascular diseases.


Assuntos
Doenças Cardiovasculares , Humanos , Mitocôndrias/genética , Mitofagia , Dinâmica Mitocondrial
15.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 47(9): 1200-1207, 2022.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-36411703

RESUMO

OBJECTIVES: Patients with tuberculosis, who are treated with long-term high-dose combined use of anti-tuberculosis drugs, can cause many adverse reactions such as liver damage, but the mechanism is still unclear. Although phosphatase and tensin homolog induced kinase 1 (PINK1)/Parkin axis might participate in the process of liver damage through regulating mitochondrial autophagy and oxidative stress in liver cells. However, the association between the mitochondrial autophagy regulated by the PINK1/Parkin axis and the liver injury induced by anti-tuberculosis drugs is unknown. This study aims to explore the mechanism of PINK1/Parkin signal axis in regulating hepatocellular injury induced by anti-tuberculosis drugs through mitochondrial autophagy, and to provide new therapeutic targets for the patients with liver damage caused by anti-tuberculosis drugs. METHODS: Mouse hepatocytes AML-12 were treated with isoniazide (INH) to induce liver injury. The mRNA and protein levels of PINK1, Parkin and autophagy associated factors were detected by real-time PCR and Western blotting in the normal AML-12 cells (control group), the AML-12 cells treated by INH (model group) and the AML-12 cells treated with INH and salidroside together (intervention group). Meantime, ELISA kit was used to detect the level of reactive oxygen species (ROS) in AML-12 cells, and the cell morphology and injury was observed by HE staining and transmission electron microscope (TEM). RESULTS: Compared with the control group, the mRNA (all P<0.01) and protein levels (all P<0.05) of PINK1, Parkin and microtubule associated protein 1 light chain 3 (LC3) were significantly decreased, the ubiquitination level was significantly decreased (P<0.05), and the ROS level was increased (P<0.05), and the hepatocellular cell showed obvious damage in the model group. Compared with the model group, the expression of PINK1, Parkin and LC3 were significantly increased in the intervention group (all P<0.05), as well as the ubiquitination level was also increased (P<0.05). The ROS level mediated by mitochondria was decreased (P<0.05). The results of HE staining and TEM showed that the cell status was improved and the damage of hepatocytes was significantly attenuated. CONCLUSIONS: In this study, the mechanism of mitochondrial autophagy mediated by PINK1/Parkin signal axis may be related to INH-induced injury in liver cells and it can regulate the damage state in vitro, indicating that Parkin is a potential molecular target for the prediction, diagnosis and treatment for liver injury induced by anti-tuberculosis drugs.


Assuntos
Carcinoma Hepatocelular , Leucemia Mieloide Aguda , Neoplasias Hepáticas , Camundongos , Animais , Mitofagia/genética , Espécies Reativas de Oxigênio , Proteínas Quinases/genética , Proteínas Quinases/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , RNA Mensageiro , Antituberculosos/farmacologia
16.
Cell Death Dis ; 13(11): 966, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36396625

RESUMO

Mitophagy is an important metabolic mechanism that modulates mitochondrial quality and quantity by selectively removing damaged or unwanted mitochondria. BNIP3 (BCL2/adenovirus e1B 19 kDa protein interacting protein 3), a mitochondrial outer membrane protein, is a mitophagy receptor that mediates mitophagy under various stresses, particularly hypoxia, since BNIP3 is a hypoxia-responsive protein. However, the underlying mechanisms that regulate BNIP3 and thus mediate mitophagy under hypoxic conditions remain elusive. Here, we demonstrate that in hypoxia JNK1/2 (c-Jun N-terminal kinase 1/2) phosphorylates BNIP3 at Ser 60/Thr 66, which hampers proteasomal degradation of BNIP3 and drives mitophagy by facilitating the direct binding of BNIP3 to LC3 (microtubule-associated protein 1 light chain 3), while PP1/2A (protein phosphatase 1/2A) represses mitophagy by dephosphorylating BNIP3 and triggering its proteasomal degradation. These findings reveal the intrinsic mechanisms cells use to regulate mitophagy via the JNK1/2-BNIP3 pathway in response to hypoxia. Thus, the JNK1/2-BNIP3 signaling pathway strongly links mitophagy to hypoxia and may be a promising therapeutic target for hypoxia-related diseases.


Assuntos
Hipóxia , Mitofagia , Humanos , Hipóxia/metabolismo , Proteínas de Membrana/metabolismo , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Mitofagia/fisiologia , Fosforilação , Proteínas Proto-Oncogênicas/metabolismo , Proteína Quinase 8 Ativada por Mitógeno/metabolismo , Proteína Quinase 9 Ativada por Mitógeno/metabolismo
17.
Oxid Med Cell Longev ; 2022: 9233749, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36406767

RESUMO

Mitophagy and oxidative stress play important roles in Parkinson's disease (PD). Dysregulated mitophagy exacerbates mitochondrial oxidative damage; however, the regulatory mechanism of mitophagy is unclear. Here, we provide a potential mechanistic link between c-Abl, a nonreceptor tyrosine kinase, and mitophagy in PD progression. We found that c-Abl activation reduces the interaction of prohibitin 2 (PHB2) and microtubule-associated protein 1 light chain 3 (LC3) and decreases the expressive level of antioxidative stress proteins, including nuclear factor erythroid 2-related factor 2 (Nrf2), NADPH quinone oxidoreductase-1 (NQO-1), and the antioxidant enzyme heme oxygenase-1 (HO-1) in 1-methyl-4-phenylpyridinium- (MPP+-) lesioned SH-SY5Y cells. Importantly, we found that MPP+ can increase the expression of phosphorylated proteins at the tyrosine site of PHB2 and the interaction of c-Abl with PHB2. We showed for the first time that PHB2 by changing tyrosine (Y) to aspartate (D) at site 121 resulted in impaired binding of PHB2 and LC3 in vitro. Moreover, silencing of PHB2 can decrease the interaction of PHB2 and LC3 and exacerbate the loss of dopaminergic neurons. We also found that STI 571, a c-Abl family kinase inhibitor, can decrease dopaminergic neuron damage and ameliorate MPTP-induced behavioral deficits in PD mice. Taken together, our findings highlight a novel molecular mechanism for aberrant PHB2 phosphorylation as an inhibitor of c-Abl activity and suggest that c-Abl and PHB2 are potential therapeutic targets for the treatment of individuals with PD. However, these results need to be further validated in PHB2 Y121D mice.


Assuntos
Neuroblastoma , Doença de Parkinson , Animais , Humanos , Camundongos , Mitofagia , Fosforilação , Doença de Parkinson/tratamento farmacológico , TYK2 Quinase/metabolismo , TYK2 Quinase/uso terapêutico , Proibitinas , 1-Metil-4-fenilpiridínio , Tirosina/metabolismo
18.
Front Immunol ; 13: 966167, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36304466

RESUMO

Mitophagy is suggested to be involved in tumor initiation and development; however, mitophagy heterogeneity in hepatocellular carcinoma (HCC) and its association with immune status and prognosis remain unclear. Differentially expressed genes (DEGs) were identified using expression profiles acquired from The Cancer Genome Atlas (TCGA). Mitophagy-related subtypes were identified using the ConsensusClusterPlus software. The differences in prognosis, clinical characteristics, and immune status, including immune cell infiltration, immune function, immune-checkpoint gene expression, and response to immunotherapy, were compared between subtypes. A mitophagy-related gene signature was constructed by applying least absolute shrinkage and selection operator regression to the TCGA cohort. The International Cancer Genome Consortium cohort and the cohort from Peking Union Medical College Hospital were utilized for validation. Carbonyl cyanide m-chlorophenylhydrazone was used to induce mitophagy in HCC cell lines to obtain our own mitophagy signature. Real-time polymerase chain reaction was used for the experimental validation of the expression of model genes. Two mitophagy-related subtypes with distinct prognoses, clinical characteristics, immune states, and biological function patterns were identified based on the mitophagy-related DEGs. The subtype that showed higher mitophagy-related DEG expression had worse survival outcomes, suppressed immune function, higher immune-checkpoint gene expression, and a better response to immunotherapy, indicating that this subpopulation in HCC may benefit from immune-checkpoint blockade therapy and other immunotherapies. A risk model consisting of nine mitophagy-related genes was constructed and its performance was confirmed in two validation cohorts. The risk score was an independent risk factor even when age, sex, and tumor stage were considered. Our study identified two distinct mitophagy subtypes and built a mitophagy signature, uncovering mitophagy heterogeneity in HCC and its association with immune status and prognosis. These findings shed light on the treatment of HCC, especially with immunotherapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Mitofagia , Biomarcadores Tumorais/genética , Imunoterapia , Fatores Imunológicos
19.
Cell Death Dis ; 13(10): 908, 2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36307395

RESUMO

A natural plant product, epigallocatechin-3-gallate (EGCG), was evaluated for its effectiveness in the regulation of osteoclastogenesis. We found that EGCG inhibited the osteoclast (OC) differentiation in vitro, and in primary bone marrow cells in a dose-dependent manner. Quantitative RT-PCR studies showed that the EGCG reduced the expression of OC differentiation markers. DCFDA, MitoSOX, and JC-1 staining revealed that the EGCG attenuated the reactive oxygen species (ROS), and mitochondrial membrane potential; and flux analysis corroborated the effect of EGCG. We further found that the EGCG inhibited mRNA and protein expressions of mitophagy-related molecules. We confirmed that the OC differentiation was inhibited by EGCG by modulating mitophagy through AKT and p38MAPK pathways. Furthermore, in silico analysis revealed that the binding of RANK and RANKL was blocked by EGCG. Overall, we defined the mechanisms of osteoclastogenesis during arthritis for developing a new therapy using a natural compound besides the existing therapeutics.


Assuntos
Catequina , Mitofagia , Catequina/farmacologia , Osteogênese , Espécies Reativas de Oxigênio/metabolismo , Mitocôndrias/metabolismo
20.
Eur Rev Med Pharmacol Sci ; 26(20): 7321-7332, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36314302

RESUMO

OBJECTIVE: Trigonella foenum-graecum L. (fenugreek) is widely used as a leafy vegetable and spice in China and North Africa. Recent studies have reported that fenugreek can reduce fatigue; however, its antifatigue mechanism remains unclear. Therefore, this study aimed to investigate the potential antifatigue effects of fenugreek extract (FE) on mitophagy and the underlying mechanisms. MATERIALS AND METHODS: We evaluated the potential effects of FE tablet on an exhaustive exercise-induced fatigue (EEF) rat model. Oxidative stress indicators and fatigue biomarkers in the serum and skeletal muscle were detected. Mitophagy and mitochondrial morphology were observed using transmission electron microscopy. The expression levels of mitochondrial autophagy-related proteins were detected using western blot and immunofluorescence. RESULTS: Compared with the model group, FE enhanced the activities of the antioxidant enzymes superoxide dismutase and glutathione peroxidase as well as total antioxidant capacity; however, it decreased the level of malondialdehyde in the serum and skeletal muscle after a 7-day treatment. Moreover, certain indicators of mitochondrial function, such as reactive oxygen species levels, ATP levels, cellular and mitochondrial Ca2+ levels, and ATPase activity, were significantly improved in the FE group compared with the model group. Finally, we found that mitophagy was induced by exhaustive exercise and inhibited by FE. Regarding mitochondrial autophagy-related proteins, the expression levels of LC3B, FUNDC1, PGAM5, PARKIN, and PINK1 in the skeletal muscle tissue were increased in the EEF group compared with the control group. After administration of FE and a positive control drug, a significant reversal in the expression of the above-mentioned proteins was noted. CONCLUSIONS: Our findings demonstrate that FE exerted antifatigue effects in the EEF rat model by regulating the mitophagy-related FUNDC1/LC3B signaling pathway rather than the PINK1/PARKIN signaling pathway.


Assuntos
Trigonella , Ratos , Animais , Trigonella/metabolismo , Antioxidantes/farmacologia , Mitofagia , Ratos Wistar , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Músculo Esquelético/metabolismo , Fadiga , Comprimidos , Proteínas Quinases , Proteínas Relacionadas à Autofagia , Ubiquitina-Proteína Ligases , Proteínas de Membrana , Proteínas Mitocondriais
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