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1.
PLoS One ; 15(6): e0234653, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32579577

RESUMO

We previously demonstrated that hexokinase II (HK2) dissociation from mitochondria during cardiac ischemia correlates with cytochrome c (cyt-c) loss, oxidative stress and subsequent reperfusion injury. However, whether HK2 release is the primary signal mediating this ischemia-induced mitochondrial dysfunction was not established. To investigate this, we studied the effects of dissociating HK2 from isolated heart mitochondria. Mitochondria isolated from Langendorff-perfused rat hearts before and after 30 min global ischemia ± ischemic preconditioning (IPC) were subject to in vitro dissociation of HK2 by incubation with glucose-6-phosphate at pH 6.3. Prior HK2 dissociation from pre- or end-ischemic heart mitochondria had no effect on their cyt-c release, respiration (± ADP) or mitochondrial permeability transition pore (mPTP) opening. Inner mitochondrial membrane morphology was assessed indirectly by monitoring changes in light scattering (LS) and confirmed by transmission electron microscopy. Although no major ultrastructure differences were detected between pre- and end-ischemia mitochondria, the amplitude of changes in LS was reduced in the latter. This was prevented by IPC but not mimicked in vitro by HK2 dissociation. We also observed more Drp1, a mitochondrial fission protein, in end-ischemia mitochondria. IPC failed to prevent this increase but did decrease mitochondrial-associated dynamin 2. In vitro HK2 dissociation alone cannot replicate ischemia-induced effects on mitochondrial function implying that in vivo dissociation of HK2 modulates end-ischemia mitochondrial function indirectly perhaps involving interaction with mitochondrial fission proteins. The resulting changes in mitochondrial morphology and cristae structure would destabilize outer / inner membrane interactions, increase cyt-c release and enhance mPTP sensitivity to [Ca2+].


Assuntos
Hexoquinase/metabolismo , Mitocôndrias Cardíacas/enzimologia , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Isquemia Miocárdica/enzimologia , Animais , Respiração Celular/efeitos dos fármacos , Dinaminas/metabolismo , Glucose-6-Fosfato/farmacologia , Hemodinâmica/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Precondicionamento Isquêmico , Ligantes , Masculino , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/ultraestrutura , Dinâmica Mitocondrial/efeitos dos fármacos , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Isquemia Miocárdica/patologia , Ligação Proteica/efeitos dos fármacos , Ratos Wistar
2.
Toxicol Appl Pharmacol ; 401: 115076, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32479918

RESUMO

Statin induced myopathy (SIM) is a main deleterious effect leading to the poor treatment compliance, while the preventive or therapeutic treatments are absent. Mounting evidences demonstrated that vitamin D plays a vital role in muscle as a direct modulator. The deficiency of vitamin D was considered as a cause of muscle dysfunction, whereas the supplementation resulted in a remission. However, there is no causal proof that vitamin D supplementation rescues SIM. Here, using the mice model of simvastatin-induced myopathy, we investigated the role of vitamin D supplementation and the mechanisms associated with mitochondria. Results indicated that simvastatin administration (80 mg/kg) impaired skeletal muscle with the increased serum creatine kinase (CK) level and the declined grip strength, which were alleviated by vitamin D supplementation. Moreover, vitamin D supplementation rescued the energy metabolism dysfunction in simvastatin-treated mice gastrocnemius by reducing the abnormal aggregation of muscular glycogen and lactic acid. Mitochondrial homeostasis plays a key role in the process of energy metabolism. Thus, the mitochondrial dysfunction is a mortal damage for the highly energy-requiring tissue. In our study, the mitochondrial cristae observed under transmission electron microscope (TEM) were lytic in simvastatin-treated gastrocnemius. Interestingly, vitamin D supplementation improved the mitochondrial cristae shape by regulating the expression of mitofusin-1/2 (MFN1/2), optic atrophy 1 (OPA1) and dynamin-related protein 1 (Drp1). As expected, the mitochondrial dysfunction and oxidative stress was mitigated by vitamin D supplementation. In conclusion, these findings suggested that moderate vitamin D supplementation rescued simvastatin induced myopathy via improving the mitochondrial cristae shape and function.


Assuntos
Suplementos Nutricionais , Mitocôndrias/efeitos dos fármacos , Doenças Musculares/induzido quimicamente , Doenças Musculares/tratamento farmacológico , Sinvastatina/toxicidade , Vitamina D/administração & dosagem , Animais , Metabolismo Energético/efeitos dos fármacos , Metabolismo Energético/fisiologia , Inibidores de Hidroximetilglutaril-CoA Redutases/toxicidade , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Membranas Mitocondriais/patologia , Doenças Musculares/metabolismo , Distribuição Aleatória
3.
Metabolism ; 105: 154182, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32061660

RESUMO

The impairment of podocyte protein filtration function caused by excessive mitochondrial calcium intake is a critical feature of diabetic nephropathy (DN). Ca2+ channel transient receptor potential cation channel subfamily V member 1 (TRPV1) has been reported to protect against ischemia-reperfusion induced acute renal injury, but there is no report about its role in DN. Here, we report that dietary capsaicin potently inhibits and reverses chronic renal structural and functional damages in db/db or streptozotocin (STZ)-induced diabetic mice in a TRPV1-dependent manner. Activation of TRPV1 by capsaicin alleviated hyperglycemia-induced mitochondrial dysfunction in podocytes, accompanied by reduced mitochondria-associated membranes (MAMs) formation and fewer Ca2+ transport from endoplasmic reticulum (ER) to mitochondria. Mechanistically, TRPV1-mediated transient Ca2+ influx activated 5' AMP-activated protein kinase (AMPK) that reduced the transcription of Fundc1, a key molecule participating in MAMs formation. Inhibition of AMPK or overexpression of Fundc1 obviously blocked the inhibitory effect of capsaicin on MAMs formation and functional decline in podocytes. These findings emphasize the critical role of mitochondrial Ca2+ homeostasis in the maintenance of normal renal function and suggest an effective intervention method to counteract DN.


Assuntos
Nefropatias Diabéticas/tratamento farmacológico , Retículo Endoplasmático/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Podócitos/efeitos dos fármacos , Canais de Cátion TRPV/metabolismo , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Canais de Cálcio/metabolismo , Capsaicina/uso terapêutico , Dieta , Inibidores Enzimáticos/farmacologia , Hiperglicemia/tratamento farmacológico , Hiperglicemia/microbiologia , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Membranas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/antagonistas & inibidores , Proteínas Mitocondriais/biossíntese
5.
J Nanobiotechnology ; 18(1): 8, 2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31918714

RESUMO

Chemotherapeutic drugs frequently encounter multidrug resistance. ATP from mitochondria helps overexpression of drug efflux pumps to induce multidrug resistance, so mitochondrial delivery as a means of "repurposing'' chemotherapeutic drugs currently used in the clinic appears to be a worthwhile strategy to pursue for the development of new anti-drug-resistant cancer agents. TPP-Pluronic F127-hyaluronic acid (HA) (TPH), with a mitochondria-targeting triphenylphosphine (TPP) head group, was first synthesized through ester bond formation. Paclitaxel (PTX)-loaded TPH (TPH/PTX) nanomicelles exhibited excellent physical properties and significantly inhibited A549/ADR cells. After TPH/PTX nanomicelles entered acidic lysosomes through macropinocytosis, the positively charged TP/PTX nanomicelles that resulted from degradation of HA by hyaluronidase (HAase) in acidic lysosomes were exposed and completed lysosomal escape at 12 h, finally localizing to mitochondria over a period of 24 h in A549/ADR cells. Subsequently, TPH/PTX caused mitochondrial outer membrane permeabilization (MOMP) by inhibiting antiapoptotic Bcl-2, leading to cytochrome C release and activation of caspase-3 and caspase-9. In an A549/ADR xenograft tumor model and a drug-resistant breast cancer-bearing mouse model with lung metastasis, TPH/PTX nanomicelles exhibited obvious tumor targeting and significant antitumor efficacy. This work presents the potential of a single, nontoxic nanoparticle (NP) platform for mitochondria-targeted delivery of therapeutics for diverse drug-resistant cancers.


Assuntos
Apoptose , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/tratamento farmacológico , Mitocôndrias/metabolismo , Nanopartículas/química , Células A549 , Animais , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Endocitose/efeitos dos fármacos , Feminino , Humanos , Ácido Hialurônico/síntese química , Ácido Hialurônico/química , Concentração Inibidora 50 , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Micelas , Mitocôndrias/efeitos dos fármacos , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Nanopartículas/ultraestrutura , Compostos Organofosforados/síntese química , Compostos Organofosforados/química , Paclitaxel/farmacologia , Paclitaxel/uso terapêutico , Poloxâmero/síntese química , Poloxâmero/química , Espectroscopia de Prótons por Ressonância Magnética , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Biochim Biophys Acta Biomembr ; 1862(2): 183064, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31521630

RESUMO

Misfolding and aggregate formation by the tau protein has been closely related with neurotoxicity in a large group of human neurodegenerative disorders, which includes Alzheimer's disease. Here, we investigate the membrane-active properties of tau oligomers on mitochondrial membranes, using minimalist in vitro model systems. Thus, exposure of isolated mitochondria to oligomeric tau evoked a disruption of mitochondrial membrane integrity, as evidenced by a combination of organelle swelling, efflux of cytochrome c and loss of the mitochondrial membrane potential. Tau-induced mitochondrial dysfunction occurred independently of the mitochondrial permeability transition (mPT) pore complex. Notably, mitochondria were rescued by pre-incubation with 10-N-nonyl acridine orange (NAO), a molecule that specifically binds cardiolipin (CL), the signature phospholipid of mitochondrial membranes. Additionally, NAO prevented direct binding of tau oligomers to isolated mitochondria. At the same time, tau proteins exhibited high affinity to CL-enriched membranes, whilst permeabilisation of lipid vesicles also strongly correlated with CL content. Intriguingly, using single-channel electrophysiology, we could demonstrate the formation of non-selective ion-conducting tau nanopores exhibiting multilevel conductances in mito-mimetic bilayers. Taken together, the data presented here advances a scenario in which toxic cytosolic entities of tau protein would target mitochondrial organelles by associating with their CL-rich membrane domains, leading to membrane poration and compromised mitochondrial structural integrity.


Assuntos
Cardiolipinas/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Proteínas tau/farmacologia , Humanos , Membranas Mitocondriais/metabolismo , Nanoporos , Permeabilidade/efeitos dos fármacos , Ligação Proteica , Multimerização Proteica
7.
Food Chem ; 311: 126008, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31869639

RESUMO

The effects of hydrogen peroxide (H2O2) on the contents of adenosine triphosphate (ATP), adenosine diphosphate (ADP) and adenosine monophosphate (AMP), the level of energy charge, and the activity of adenosine triphosphatase (ATPase) in pulp of harvested longan fruit, and its association with longan pulp breakdown occurrence were studied. The results showed that, compared to the control longans, H2O2-treated longans exhibited a higher index of pulp breakdown, a higher amount of AMP, but lower levels of ATP, ADP and energy charge. H2O2-treated longans also exhibited lower activities of Mg2+-ATPase, Ca2+-ATPase, and H+-ATPase in mitochondrial membrane, vacuolar membrane, and plasma membrane as compared to the control longans. Above findings demonstrated that H2O2 caused longan pulp breakdown by depleting energy and lowering the ATPase activity, indicating H2O2-induced pulp breakdown in harvested longan fruit was due to energy deficit.


Assuntos
Adenosina Trifosfatases/metabolismo , Peróxido de Hidrogênio/metabolismo , Sapindaceae/metabolismo , Difosfato de Adenosina/metabolismo , Adenosina Trifosfatases/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Metabolismo Energético/efeitos dos fármacos , Armazenamento de Alimentos , Frutas/metabolismo , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/farmacologia , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo
8.
Stem Cell Res Ther ; 10(1): 392, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31847882

RESUMO

BACKGROUND: Chondrogenesis represents a highly dynamic cellular process that leads to the establishment of various types of cartilage. However, when stress-related injuries occur, a rapid and efficient regeneration of the tissues is necessary to maintain cartilage integrity. Mesenchymal stem cells (MSCs) are known to exhibit high capacity for self-renewal and pluripotency effects, and thus play a pivotal role in the repair and regeneration of damaged cartilage. On the other hand, the influence of certain pathological conditions such as metabolic disorders on MSCs can seriously impair their regenerative properties and thus reduce their therapeutic potential. OBJECTIVES: In this investigation, we attempted to improve and potentiate the in vitro chondrogenic ability of adipose-derived mesenchymal stromal stem cells (ASCs) isolated from horses suffering from metabolic syndrome. METHODS: Cultured cells in chondrogenic-inductive medium supplemented with Cladophora glomerata methanolic extract were experimented for expression of the main genes and microRNAs involved in the differentiation process using RT-PCR, for their morphological changes through confocal and scanning electron microscopy and for their physiological homeostasis. RESULTS: The different added concentrations of C. glomerata extract to the basic chondrogenic inductive culture medium promoted the proliferation of equine metabolic syndrome ASCs (ASCsEMS) and resulted in chondrogenic phenotype differentiation and higher mRNA expression of collagen type II, aggrecan, cartilage oligomeric matrix protein, and Sox9 among others. The results reveal an obvious inhibitory effect of hypertrophy and a strong repression of miR-145-5p, miR-146-3p, and miR-34a and miR-449a largely involved in cartilage degradation. Treated cells additionally exhibited significant reduced apoptosis and oxidative stress, as well as promoted viability and mitochondrial potentiation. CONCLUSION: Chondrogenesis in EqASCsEMS was found to be prominent after chondrogenic induction in conditions containing C. glomerata extract, suggesting that the macroalgae could be considered for the enhancement of ASC cultures and their reparative properties.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Clorófitas/química , Condrogênese/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Síndrome Metabólica/patologia , Extratos Vegetais/farmacologia , Agrecanas/genética , Agrecanas/metabolismo , Animais , Apoptose/efeitos dos fármacos , Clorófitas/metabolismo , Condrócitos/citologia , Condrócitos/metabolismo , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Cavalos , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Síndrome Metabólica/metabolismo , MicroRNAs/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/fisiologia , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo
9.
PLoS One ; 14(11): e0224132, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31697708

RESUMO

Succinate dehydrogenase (SDH) inhibitors (SDHIs) are used worldwide to limit the proliferation of molds on plants and plant products. However, as SDH, also known as respiratory chain (RC) complex II, is a universal component of mitochondria from living organisms, highly conserved through evolution, the specificity of these inhibitors toward fungi warrants investigation. We first establish that the human, honeybee, earthworm and fungal SDHs are all sensitive to the eight SDHIs tested, albeit with varying IC50 values, generally in the micromolar range. In addition to SDH, we observed that five of the SDHIs, mostly from the latest generation, inhibit the activity of RC complex III. Finally, we show that the provision of glucose ad libitum in the cell culture medium, while simultaneously providing sufficient ATP and reducing power for antioxidant enzymes through glycolysis, allows the growth of RC-deficient cells, fully masking the deleterious effect of SDHIs. As a result, when glutamine is the major carbon source, the presence of SDHIs leads to time-dependent cell death. This process is significantly accelerated in fibroblasts derived from patients with neurological or neurodegenerative diseases due to RC impairment (encephalopathy originating from a partial SDH defect) and/or hypersensitivity to oxidative insults (Friedreich ataxia, familial Alzheimer's disease).


Assuntos
Transporte de Elétrons/efeitos dos fármacos , Praguicidas/farmacologia , Succinato Desidrogenase/antagonistas & inibidores , Animais , Antioxidantes/metabolismo , Abelhas/metabolismo , Células Cultivadas , Farmacorresistência Fúngica/efeitos dos fármacos , Proteínas Fúngicas/farmacologia , Fungos/metabolismo , Humanos , Membranas Mitocondriais/efeitos dos fármacos , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Oligoquetos/metabolismo , Succinato Desidrogenase/metabolismo
10.
Molecules ; 24(18)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31547332

RESUMO

Some studies have demonstrated that acrylamide (AA) was correlated with oxidative stress, resulting in physical damage. The jackfruit flake was an immature pulp that contained a high level of antioxidant activity. This study aimed to assess the defensive efficacy of jackfruit flake in AA-induced oxidative stress before and after simulated gastrointestinal digestion. Our results indicate that the total polyphenol content of Jackfruit flake digest (Digestive products of jackfruit flake after gastrointestinal, JFG) was diminished; however, JFG had raised the relative antioxidant capacity compared to Jackfruit flake extract (JFE). Additionally, the results of High Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS) implied that a proportion of compounds were degraded/converted into other unknown and/or undetected metabolites. Further, by high content analysis (HCA) techniques, JFG markedly reduced cytotoxicity and excessive production of reactive oxygen species (ROS) in cells, thereby alleviating mitochondrial disorders. In this study, it may be converted active compounds after digestion that had preferable protective effects against AA-induced oxidative damage.


Assuntos
Antioxidantes/análise , Artocarpus/química , Estresse Oxidativo/efeitos dos fármacos , Acrilamida/toxicidade , Apoptose/efeitos dos fármacos , Células CACO-2 , Cromatografia Líquida de Alta Pressão , Digestão , Humanos , Intestino Delgado/efeitos dos fármacos , Intestino Delgado/patologia , Espectrometria de Massas , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Membranas Mitocondriais/efeitos dos fármacos , Permeabilidade , Polifenóis/análise , Espécies Reativas de Oxigênio/metabolismo , Estômago/efeitos dos fármacos
11.
Int J Mol Sci ; 20(17)2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31438500

RESUMO

Contrast-induced acute kidney injury (CI-AKI) is the third most common cause of hospital associated kidney damage. Potential mechanisms of CI-AKI may involve diminished renal hemodynamics, inflammatory responses, and direct cytotoxicity. The hypothesis for this study is that diatrizoic acid (DA) induces direct cytotoxicity to human proximal tubule (HK-2) cells via calcium dysregulation, mitochondrial dysfunction, and oxidative stress. HK-2 cells were exposed to 0-30 mg I/mL DA or vehicle for 2-24 h. Conversion of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and trypan blue exclusion indicated a decrease in mitochondrial and cell viability within 2 and 24 h, respectively. Mitochondrial dysfunction was apparent within 8 h post exposure to 15 mg I/mL DA as shown by Seahorse XF cell mito and Glycolysis Stress tests. Mitophagy was increased at 8 h by 15 mg I/mL DA as confirmed by elevated LC3BII/I expression ratio. HK-2 cells pretreated with calcium level modulators BAPTA-AM, EGTA, or 2-aminophenyl borinate abrogated DA-induced mitochondrial damage. DA increased oxidative stress biomarkers of protein carbonylation and 4-hydroxynonenol (4HNE) adduct formation. Caspase 3 and 12 activation was induced by DA compared to vehicle at 24 h. These studies indicate that clinically relevant concentrations of DA impair HK-2 cells by dysregulating calcium, inducing mitochondrial turnover and oxidative stress, and activating apoptosis.


Assuntos
Cálcio/metabolismo , Meios de Contraste/efeitos adversos , Diatrizoato/efeitos adversos , Mitofagia/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Lesão Renal Aguda/metabolismo , Apoptose/efeitos dos fármacos , Western Blotting , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Superóxido Dismutase/metabolismo
12.
J Agric Food Chem ; 67(33): 9265-9276, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31361479

RESUMO

Fungal infections significantly alter the emissions of volatile organic compounds (VOCs) by plants, but the mechanisms for VOCs affecting fungal infections of plants remain largely unknown. Here, we found that infection by Botrytis cinerea upregulated linalool production by strawberries and fumigation with linalool was able to inhibit the infection of fruits by the fungus. Linalool treatment downregulated the expression of rate-limiting enzymes in the ergosterol biosynthesis pathway, and this reduced the ergosterol content in the fungi cell membrane and impaired membrane integrity. Linalool treatment also caused damage to mitochondrial membranes by collapsing mitochondrial membrane potential and also downregulated genes involved in adenosine triphosphate (ATP) production, resulting in a significant decrease in the ATP content. Linalool treatment increased the levels of reactive oxygen species (ROS), in response to which the treated fungal cells produced more of the ROS scavenger pyruvate. RNA-Seq and proteomic analysis data showed that linalool treatment slowed the rates of transcription and translation.


Assuntos
Botrytis/efeitos dos fármacos , Fragaria/metabolismo , Frutas/microbiologia , Monoterpenos/metabolismo , Doenças das Plantas/microbiologia , Compostos Orgânicos Voláteis/metabolismo , Monoterpenos Acíclicos , Trifosfato de Adenosina/metabolismo , Botrytis/crescimento & desenvolvimento , Fragaria/química , Fragaria/microbiologia , Frutas/química , Frutas/metabolismo , Interações Hospedeiro-Patógeno , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Monoterpenos/farmacologia , Doenças das Plantas/prevenção & controle , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteômica , Espécies Reativas de Oxigênio/metabolismo , Compostos Orgânicos Voláteis/farmacologia
13.
Am J Chin Med ; 47(5): 1057-1073, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31327236

RESUMO

Ginkgo biloba extracts (EGb) alleviate myocardial ischemia/reperfusion (MI/R) injury. However, the underlying mechanisms have not yet been characterized. This study aimed to investigate whether activation of large-conductance Ca2+-activated K+ channels at the inner mitochondrial membrane (mitoBKCa) of cardiomyocytes is involved in Ginkgo biloba extract-mediated cardioprotection. Shuxuening injection (SXNI, 12.5ml/kg/d), a widely prescribed herbal medicine containing Ginkgo biloba extracts in China, or vehicle, was administered to C57BL/6 mice via tail vein injection for one week prior to surgical procedures. The mitoBKCa blocker paxilline (PAX) (1ml/kg, 115 nM) was administered via tail vein injection 30min prior to the onset of ischemia. The mice were randomly divided into the following groups: Sham, MI/R, MI/R+SXNI, and MI/R+SXNI+PAX. MI/R was induced by ligating the left anterior descending coronary artery for 30min with subsequent reperfusion for 24h. SXNI pretreatment conferred cardioprotective effects against MI/R injury as evidenced by reduced infarct size, improved cardiac function, and improved mitochondrial function. However, these effects were abrogated by co-administration with PAX. In addition, activation of mitoBKCa by Ginkgo biloba extract EGb761 reduced hypoxia/reoxygenation (H/R)-induced cardiomyocyte injury in vitro through the inhibition of mitochondrial fragmentation, restoration of the mitochondrial membrane potential, decreased generation of superoxide, and inhibition of apoptosis which is associated with alleviating mitochondrial Ca2+ overload. These results indicated that Ginkgo biloba extracts pretreatment protected against MI/R injury via activation of mitoBKCa.


Assuntos
Ginkgo biloba/química , Canais de Potássio Ativados por Cálcio de Condutância Alta/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Miócitos Cardíacos/efeitos dos fármacos , Extratos Vegetais/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , China , Humanos , Canais de Potássio Ativados por Cálcio de Condutância Alta/genética , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Membranas Mitocondriais/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miócitos Cardíacos/metabolismo
14.
Biochim Biophys Acta Bioenerg ; 1860(8): 659-678, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31247171

RESUMO

Hypoxia causes mitochondrial cristae widening, enabled by the ~20% degradation of Mic60/mitofilin, with concomitant clustering of the MICOS complex, reflecting the widening of crista junctions (outlets) (Plecitá-Hlavatá et al. FASEB J., 2016 30:1941-1957). Attempting to accelerate metabolism by the addition of membrane-permeant dimethyl-2-oxoglutarate (dm2OG) to HepG2 cells pre-adapted to hypoxia, we found cristae narrowing by transmission electron microscopy. Glycolytic HepG2 cells, which downregulate hypoxic respiration, instantly increased respiration with dm2OG. Changes in intracristal space (ICS) morphology were also revealed by 3D super-resolution microscopy using Eos-conjugated ICS-located lactamase-ß. Cristae topology was resolved in detail by focused-ion beam/scanning electron microscopy (FIB/SEM). The spatial relocations of key cristae-shaping proteins were indicated by immunocytochemical stochastic 3D super-resolution microscopy (dSTORM), while analyzing inter-antibody-distance histograms: i) ATP-synthase dimers exhibited a higher fraction of shorter inter-distances between bound F1-α primary Alexa-Fluor-647-conjugated antibodies, indicating cristae narrowing. ii) Mic60/mitofilin clusters (established upon hypoxia) decayed, restoring isotropic random Mic60/mitofilin distribution (a signature of normoxia). iii) outer membrane SAMM50 formed more focused clusters. Less abundant fractions of higher ATP-synthase oligomers of hypoxic samples on blue-native electrophoresis became more abundant fractions at the high dm2OG load and at normoxia. This indicates more labile ATP-synthase dimeric rows established at crista rims upon hypoxia, strengthened at normoxia or dm2OG-substrate load. Hypothetically, the increased Krebs substrate load stimulates the cross-linking/strengthening of rows of ATP-synthase dimers at the crista rims, making them sharper. Crista narrowing ensures a more efficient coupling of proton pumping to ATP synthesis. We demonstrated that cristae morphology changes even within minutes.


Assuntos
Ácidos Cetoglutáricos/farmacologia , Mitocôndrias/ultraestrutura , Membranas Mitocondriais/ultraestrutura , Respiração Celular , Dimerização , Células Hep G2 , Humanos , Hipóxia , Microscopia Eletrônica de Transmissão , Membranas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , ATPases Mitocondriais Próton-Translocadoras/metabolismo
15.
Oxid Med Cell Longev ; 2019: 1826303, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31249641

RESUMO

Pancreatic ß-cells are vulnerable to oxidative stress due to their low content of redox buffers, such as glutathione, but possess a rich content of thioredoxin, peroxiredoxin, and other proteins capable of redox relay, transferring redox signaling. Consequently, it may be predicted that cytosolic antioxidants could interfere with the cytosolic redox signaling and should not be recommended for any potential therapy. In contrast, mitochondrial matrix-targeted antioxidants could prevent the primary oxidative stress arising from the primary superoxide sources within the mitochondrial matrix, such as at the flavin (IF) and ubiquinone (IQ) sites of superoxide formation within respiratory chain complex I and the outer ubiquinone site (IIIQ) of complex III. Therefore, using time-resolved confocal fluorescence monitoring with MitoSOX Red, we investigated various effects of mitochondria-targeted antioxidants in model pancreatic ß-cells (insulinoma INS-1E cells) and pancreatic islets. Both SkQ1 (a mitochondria-targeted plastoquinone) and a suppressor of complex III site Q electron leak (S3QEL) prevented superoxide production released to the mitochondrial matrix in INS-1E cells with stimulatory glucose, where SkQ1 also exhibited an antioxidant role for UCP2-silenced cells. SkQ1 acted similarly at nonstimulatory glucose but not in UCP2-silenced cells. Thus, UCP2 can facilitate the antioxidant mechanism based on SkQ1+ fatty acid anion- pairing. The elevated superoxide formation induced by antimycin A was largely prevented by S3QEL, and that induced by rotenone was decreased by SkQ1 and S3QEL and slightly by S1QEL, acting at complex I site Q. Similar results were obtained with the MitoB probe, for the LC-MS-based assessment of the 4 hr accumulation of reactive oxygen species within the mitochondrial matrix but for isolated pancreatic islets. For 2 hr INS-1E incubations, some samples were influenced by the cell death during the experiment. Due to the frequent dependency of antioxidant effects on metabolic modes, we suggest a potential use of mitochondria-targeted antioxidants for the treatment of prediabetic states after cautious nutrition-controlled tests. Their targeted delivery might eventually attenuate the vicious spiral leading to type 2 diabetes.


Assuntos
Antioxidantes/farmacologia , Células Secretoras de Insulina/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Membranas Mitocondriais/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Animais , Células Cultivadas , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Membranas Mitocondriais/metabolismo , Membranas Mitocondriais/patologia , Compostos Organofosforados , Oxirredução , Fenantridinas , Proteína Desacopladora 2/metabolismo
16.
Life Sci ; 231: 116587, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31220526

RESUMO

The endoplasmic reticulum (ER) and mitochondria are two important organelles in cells. Mitochondria-associated membranes (MAMs) are lipid raft-like domains formed in the ER membranes that are in close apposition to mitochondria. They play an important role in signal transmission between these two essential organelles. When cells are exposed to internal or external stressful stimuli, the ER will activate an adaptive response called the ER stress response, which has a significant effect on mitochondrial function. Mitochondrial quality control is an important mechanism to ensure the functional integrity of mitochondria and the effect of ER stress on mitochondrial quality control through MAMs is of great significance. Therefore, in this review, we introduce ER stress and mitochondrial quality control, and discuss how ER stress signals are transmitted to mitochondria through MAMs. We then review the important roles of MAMs in mitochondrial quality control under ER stress.


Assuntos
Estresse do Retículo Endoplasmático/fisiologia , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Animais , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio , Retículo Endoplasmático/metabolismo , Humanos , Microdomínios da Membrana , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/fisiologia
17.
Biochim Biophys Acta Biomembr ; 1861(8): 1510-1521, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31226245

RESUMO

Hassallidins are cyclic glycolipopeptides produced by cyanobacteria and other prokaryotes. The hassallidin structure consists of a peptide ring of eight amino acids where a fatty acid chain, additional amino acids, and sugar moieties are attached. Hassallidins show antifungal activity against several opportunistic human pathogenic fungi, but does not harbor antibacterial effects. However, they have not been studied on mammalian cells, and the mechanism of action is unknown. We purified hassallidin D from cultured cyanobacterium Anabaena sp. UHCC 0258 and characterized its effect on mammalian and fungal cells. Ultrastructural analysis showed that hassallidin D disrupts cell membranes, causing a lytic/necrotic cell death with rapid presence of disintegrated outer membrane, accompanied by internalization of small molecules such as propidium iodide into the cells. Furthermore, artificial liposomal membrane assay showed that hassallidin D selectively targets sterol-containing membranes. Finally, in silico membrane modeling allowed us to study the interaction between hassallidin D and membranes in detail, and confirm the role of cholesterol for hassallidin-insertion into the membrane. This study demonstrates the mechanism of action of the natural compound hassallidin, and gives further insight into how bioactive lipopeptide metabolites selectively target eukaryotic cell membranes.


Assuntos
Antifúngicos/metabolismo , Antineoplásicos/metabolismo , Glicolipídeos/metabolismo , Glicopeptídeos/metabolismo , Lipopeptídeos/metabolismo , Lipídeos de Membrana/metabolismo , Esteróis/metabolismo , Anabaena/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios de Seleção de Medicamentos Antitumorais , Glicopeptídeos/isolamento & purificação , Glicopeptídeos/farmacologia , Humanos , Lipopeptídeos/isolamento & purificação , Lipopeptídeos/farmacologia , Membranas Mitocondriais/efeitos dos fármacos
18.
Pharmacology ; 104(1-2): 28-35, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31039578

RESUMO

BACKGROUND: Anthroquinones are considered remarkable anticancer agents. Chrysophanol is an important anthroquinone and it has shown to have the potential to inhibit the growth of the range of cancers. However, there are no studies regarding the anticancer effects of chrysophanol against the malignant meningioma of optic nerve. In this review, the potential of chrysophanol in the treatment of malignant -meningioma of optic nerve was explored by evaluating its anticancer activity against the malignant meningioma CH157-MN cells. MATERIALS AND METHODS: The 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide assay was used for cell viability determination. The 4',6-diamidino-2-phenylindole (DAPI), acridine orange and ethidium bromide (AO/EB) and annexin V/PI assays were used to determine the induction of apoptosis. The potential of reactive oxygen species and the mitochondrial membrane was estimated by flow cytometry. Western blot analysis was performed to determine the protein expression. RESULTS: The results showed that chrysophanol caused significant decline in the viability of the CH157-MN cells and exhibited an IC50 of 30 µmol/L. Anticancer effects were found to be due to the induction of apoptosis as evident form the DAPI and AO/EB staining. The annexin V/PI staining revealed that the apoptotic cells increased from 1.77% in control to 37.21% at 60 µmol/L concentration of chrysophanol. The Bcl-2/Bax expression ratio was decreased and the caspases-3 and 9 were activated upon chrysophanol treatment of the CH157-MN cells. Chrysophanol also triggered the formation of reactive oxygen species and reduction of the mitochondrial membrane potential in the CH157-MN cells and also blocked the Mitogen-activated protein kinase signaling pathway. CONCLUSION: The findings of the present study suggest that chrysophanol may prove beneficial in the treatment of malignant meningioma of optic nerve. Key Message: The study revealed the anticancer potential of chrysophanol against the malignant optic nerve meningioma.


Assuntos
Antraquinonas/farmacologia , Neoplasias Meníngeas/tratamento farmacológico , Meningioma/tratamento farmacológico , Neoplasias do Nervo Óptico/tratamento farmacológico , Antraquinonas/uso terapêutico , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Concentração Inibidora 50 , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neoplasias Meníngeas/patologia , Meningioma/patologia , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Neoplasias do Nervo Óptico/patologia
19.
PLoS One ; 14(5): e0216078, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31048849

RESUMO

African trypanosomiasis remains a lethal disease to both humans and livestock. The disease persists due to limited drug availability, toxicity and drug resistance, hence the need for a better understanding of the parasite's biology and provision of alternative forms of therapy. In this study, the in vitro effects of phenolic acids were assessed for their trypanocidal activities against Trypanosoma brucei brucei. The effect of the phenolic acids on Trypanosoma brucei brucei was determined by the alamarBlue assay. The cell cycle effects were determined by flow cytometry and parasite morphological analysis was done by microscopy. Effect on cell proliferation was determined by growth kinetic analysis. Reverse Transcriptase quantitative Polymerase Chain Reaction was used to determine expression of iron dependent enzymes and iron distribution determined by atomic absorption spectroscopy. Gallic acid gave an IC50 of 14.2±1.5 µM. Deferoxamine, gallic acid and diminazene aceturate showed a dose dependent effect on the cell viability and the mitochondrion membrane integrity. Gallic acid, deferoxamine and diminazene aceturate caused loss of kinetoplast in 22%, 26% and 82% of trypanosomes respectively and less than 10% increase in the number of trypanosomes in S phase was observed. Gallic acid caused a 0.6 fold decrease, 50 fold increase and 7 fold increase in the expression levels of the transferrin receptor, ribonucleotide reductase and cyclin 2 genes respectively while treatment with deferoxamine and diminazene aceturate also showed differential expressions of the transferrin receptor, ribonucleotide reductase and cyclin 2 genes. The data suggests that gallic acid possibly exerts its effect on T. brucei via iron chelation leading to structural and morphological changes and arrest of the cell cycle. These together provide information on the cell biology of the parasite under iron starved conditions and provide leads into alternative therapeutic approaches in the treatment of African trypanosomiasis.


Assuntos
Hidroxibenzoatos/farmacologia , Trypanosoma brucei brucei/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Desferroxamina/farmacologia , Diminazena/análogos & derivados , Diminazena/farmacologia , Resistência a Medicamentos/efeitos dos fármacos , Ácido Gálico/farmacologia , Humanos , Ferro/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Tripanossomicidas/farmacologia , Trypanosoma/efeitos dos fármacos , Trypanosoma brucei brucei/patogenicidade , Tripanossomíase Africana/parasitologia
20.
Med Sci Monit ; 25: 2935-2942, 2019 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-31005958

RESUMO

BACKGROUND Thyroid cancer causes considerable mortality and morbidity across the globe. Owing to the unavailability of biomarkers and the adverse effects of existing drugs, there is an urgent need to develop efficient chemotherapy for the treatment of thyroid cancers. Plants have served as exceptional source of drugs for the treatment of lethal diseases. The purpose of this study was to evaluate the anticancer effects of ferruginol against thyroid cancer cells. MATERIAL AND METHODS We monitored the cell proliferation rate using 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Apoptosis was detected using 4',6-diamidino-2-phenylindole (DAPI), acridine orange/ethidium bromide (AO/EB), and annexin V/propidium iodide (PI) staining. Reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) levels were examined by fluorescence microscopy. Protein expressed was examined by western blotting. RESULTS We found that ferruginol exerted potent antiproliferative action against thyroid cancer cells, and an IC50 of 12 µM was observed for ferruginol against the MDA-T32 cell line. The toxic effects of ferruginol were less pronounced against normal cells. The anticancer effects of ferruginol were likely due to the induction of apoptosis which was also associated with upregulation of Bax and downregulation of Bcl-2. Ferruginol also caused ROS mediated alterations in the MMP of MDA-T32 cells. In MDA-T32 cells, ferruginol might also block the MAPK and PI3K/AKT signaling pathway, which is believed to be an important therapeutic target of anticancer drugs. CONCLUSIONS In conclusion, in view of the results of this study, it might be suggested that ferruginol might serve as an essential lead molecule for the treatment of thyroid cancer provided further in-depth studies especially studying ferruginol toxicological as well as in vivo studies are needed.


Assuntos
Abietanos/farmacologia , Neoplasias da Glândula Tireoide/tratamento farmacológico , Abietanos/metabolismo , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , China , Diterpenos/metabolismo , Diterpenos/farmacologia , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Membranas Mitocondriais/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
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