RESUMO
This study was designed to discern the effect of heavy scavenger metallothionein on glutathione (GSH) deprivation-evoked cardiac anomalies and mechanisms involved with an emphasis on ferroptosis. Wild-type and cardiac metallothionein transgenic mice received GSH synthase inhibitor buthionine sulfoximine (BSO; 30 mmol/L in drinking water) for 14 days before assessment of myocardial morphology and function. BSO evoked cardiac remodeling and contractile anomalies, including cardiac hypertrophy, interstitial fibrosis, enlarged left ventricular chambers, deranged ejection fraction, fraction shortening, cardiomyocyte contractile capacity, intracellular Ca2+ handling, sarcoplasmic reticulum Ca2+ reuptake, loss of mitochondrial integrity (mitochondrial swelling, loss of aconitase activity), mitochondrial energy deficit, carbonyl damage, lipid peroxidation, ferroptosis, and apoptosis. Metallothionein itself did not affect myocardial morphology and function, although it mitigated BSO-provoked myocardial anomalies, loss of mitochondrial integrity and energy, and ferroptosis. Immunoblotting revealed down-regulated sarco(endo)plasmic reticulum Ca2+-ATPase 2a, glutathione peroxidase 4, ferroptosis-suppressing CDGSH iron-sulfur domain 1 (CISD1), and mitochondrial regulating glycogen synthase kinase-3ß phosphorylation with elevated p53, myosin heavy chain-ß isozyme, IκB phosphorylation, and solute carrier family 7 member 11 (SLC7A11) as well as unchanged SLC39A1, SLC1A5, and ferroptosis-suppressing protein 1 following BSO challenge, all of which, except glutamine transporter SLC7A11 and p53, were abrogated by metallothionein. Inhibition of CISD1 using pioglitazone nullified GSH-offered benefit against BSO-induced cardiomyocyte ferroptosis and contractile and intracellular Ca2+ derangement. Taken together, these findings support a regulatory modality for CISD1 in the impedance of ferroptosis in metallothionein-offered protection against GSH depletion-evoked cardiac aberration.
Assuntos
Cardiomiopatias , Ferroptose , Glutationa , Metalotioneína , Proteínas Mitocondriais , Animais , Camundongos , Butionina Sulfoximina/farmacologia , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Ferroptose/efeitos dos fármacos , Glutationa/metabolismo , Metalotioneína/metabolismo , Camundongos Transgênicos , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Miócitos Cardíacos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Proteínas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismoRESUMO
Cannabidiol (CBD) reportedly exerts protective effects against many psychiatric disorders and neurodegenerative diseases, but the mechanisms are poorly understood. In this study, we explored the molecular mechanism of CBD against cerebral ischemia. HT-22 cells or primary cortical neurons were subjected to oxygen-glucose deprivation insult followed by reoxygenation (OGD/R). In both HT-22 cells and primary cortical neurons, CBD pretreatment (0.1, 0.3, 1 µM) dose-dependently attenuated OGD/R-induced cell death and mitochondrial dysfunction, ameliorated OGD/R-induced endoplasmic reticulum (ER) stress, and increased the mitofusin-2 (MFN2) protein level in HT-22 cells and primary cortical neurons. Knockdown of MFN2 abolished the protective effects of CBD. CBD pretreatment also suppressed OGD/R-induced binding of Parkin to MFN2 and subsequent ubiquitination of MFN2. Overexpression of Parkin blocked the effects of CBD in reducing MFN2 ubiquitination and reduced cell viability, whereas overexpressing MFN2 abolished Parkin's detrimental effects. In vivo experiments were conducted on male rats subjected to middle cerebral artery occlusion (MCAO) insult, and administration of CBD (2.5, 5 mg · kg-1, i.p.) dose-dependently reduced the infarct volume and ER stress in the brains. Moreover, the level of MFN2 within the ischemic penumbra of rats was increased by CBD treatment, while the binding of Parkin to MFN2 and the ubiquitination of MFN2 was decreased. Finally, short hairpin RNA against MFN2 reversed CBD's protective effects. Together, these results demonstrate that CBD protects brain neurons against cerebral ischemia by reducing MFN2 degradation via disrupting Parkin's binding to MFN2, indicating that MFN2 is a potential target for the treatment of cerebral ischemia.
Assuntos
Isquemia Encefálica , Canabidiol , GTP Fosfo-Hidrolases , Fármacos Neuroprotetores , Traumatismo por Reperfusão , Animais , Masculino , Ratos , Apoptose , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Canabidiol/farmacologia , Glucose/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Neuroproteção , Fármacos Neuroprotetores/farmacologia , Oxigênio/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Ubiquitina-Proteína Ligases/metabolismo , GTP Fosfo-Hidrolases/efeitos dos fármacos , GTP Fosfo-Hidrolases/metabolismo , Proteínas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/metabolismoRESUMO
In the ischemic brain, hypoxia leads to mitochondrial dysfunction, insufficient energy production, and astrocyte activation. Yet, most studies investigating mitochondrial dysfunction in cerebral ischemia have focused exclusively on neurons. This review will highlight the importance of the morphological, molecular, and functional heterogeneity of astrocytes in their role in brain injuries and explore how activated astrocytes exhibit calcium imbalance, reactive oxygen species overproduction, and apoptosis. In addition, special focus will be given to the role of the mitochondrial protein frataxin in activated astrocytes during ischemia and its putative role in the pharmacological management of cerebral ischemia.
Assuntos
Isquemia Encefálica , Proteínas Mitocondriais , Humanos , Astrócitos/metabolismo , Lesões Encefálicas/tratamento farmacológico , Lesões Encefálicas/metabolismo , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Mitocôndrias/fisiologia , Proteínas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , FrataxinaRESUMO
Studies have found that Platonin has neuroprotective effect, but its molecular mechanism needs further study. We found that at the early stage of cerebral ischemia/reperfusion injury, Platonin treatment significantly reduced cerebral infarct lesions, improved neurological scores, and exerted neuroprotective effects. Our group has shown that NLRP3 inflammasomes activation is required to mediate neuronal injury during cerebral ischemia /reperfusion injury. The brain protective effect of Platonin is related to its ability to effectively regulate autophagy and NLRP3 inflammasomes-derived inflammation. Platonin treatment effectively induced autophagy (LC3II/I, p62) and reduced NLRP3 inflammasomes activation(NLRP3, cleaved-IL-1ßï¼cleaved-IL-18, cleaved-caspase1). However, 3-MA (15 mg/kg) treatment downregulated the inhibitory effect of Platonin on NLRP3 inflammasomes. We also studied the location of BNIP3 in Platonin-mediated neuroprotection and found that Platonin induced the expression of autophagic protein BNIP3 and enhanced the co-immunoprecipitation of BNIP3 with LC3, and double-labeled immunofluorescence also showed enhanced co-localization of BNIP3 with LC3. Finally, si-BNIP3 transfection attenuated the co localization of BNIP3 with LC3, decreased the autophagy activity to a certain extent and blocked the inhibition of NLRP3 inflammasomes-derived inflammation by Platonin. This study demonstrated that Platonin may play a neuroprotection role in cerebral I / R injury by inhibiting NLRP3 inflammasomes activation through upregulating autophagy via BNIP3 / LC3 pathway.
Assuntos
Autofagia/efeitos dos fármacos , Inflamassomos/efeitos dos fármacos , Proteínas de Membrana/efeitos dos fármacos , Proteínas Associadas aos Microtúbulos/efeitos dos fármacos , Proteínas Mitocondriais/efeitos dos fármacos , Proteína 3 que Contém Domínio de Pirina da Família NLR/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Tiazóis/farmacologia , Animais , Modelos Animais de Doenças , RatosRESUMO
O-GlcNAcylation is a nutrient-driven post-translational modification known as a metabolic sensor that links metabolism to cellular function. Recent evidences indicate that the activation of O-GlcNAc pathway is a potential pro-survival pathway and that acute enhancement of this response is conducive to the survival of cells and tissues. 2-(4-Methoxyphenyl)ethyl-2-acetamido-2-deoxy-ß-d-pyranoside (SalA-4g), is a salidroside analogue synthesized in our laboratory by chemical structure-modification, with a phenyl ring containing a para-methoxy group and a sugar ring consisting of N-acetylglucosamine. We have previously shown that SalA-4g elevates levels of protein O-GlcNAc and improves neuronal tolerance to ischemia. However, the specific target of SalA-4g regulating O-GlcNAcylation remains unknown. To address these questions, in this study, we have focused on mitochondrial network homeostasis mediated by O-GlcNAcylation in SalA-4g's neuroprotection in primary cortical neurons under ischemic-like conditions. O-GlcNAc-modified mitochondria induced by SalA-4g demonstrated stronger neuroprotection under oxygen glucose deprivation and reoxygenation stress, including the improvement of mitochondrial homeostasis and bioenergy, and inhibition of mitochondrial apoptosis pathway. Blocking mitochondrial protein O-GlcNAcylation with OSMI-1 disrupted mitochondrial network homeostasis and antagonized the protective effects of SalA-4g. Collectively, these data demonstrate that mitochondrial homeostasis mediated by mitochondrial protein O-GlcNAcylation is critically involved in SalA-4g neuroprotection.
Assuntos
Acetilglucosamina/análogos & derivados , Metabolismo Energético , Isquemia/prevenção & controle , Mitocôndrias/efeitos dos fármacos , Proteínas Mitocondriais/química , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Acetilglucosamina/farmacologia , Animais , Glucose/metabolismo , Glicosilação , Homeostase , Isquemia/metabolismo , Isquemia/patologia , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteínas Mitocondriais/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Oxigênio/metabolismo , Processamento de Proteína Pós-Traducional , Ratos , Ratos Sprague-DawleyRESUMO
Colorectal cancer (CRC) ranks third in incidence and second in mortality among all types of cancer, and due to its insidious onset and lack of early symptoms, it is usually diagnosed at a later stage. Saponins, a class of compounds abundant in plants, have been reported to possess prominent antitumour properties. The use of ginsenoside Rg3 in the clinical setting was authorized by the National Medicinal Products Administration of China. In the present study, total saponins from Rhizoma Panacis Majoris (RPMTG) were prepared, and the pharmacological mechanisms underlying the antiCRC effects of RPMTG were investigated. The effect of RPMTG on the proliferation, cell cycle progression and apoptosis of HCT116 and SW620 cells were detected by MTT, flow cytometry and western blotting assays, and it was demonstrated that RPMTG could inhibit the proliferation of HCT116 and SW620 cells with IC50 values of 315.8 and 355.1 µg/ml, respectively, induce cell cycle arrest in the S and G0/G1 phase, and trigger apoptosis by downregulating the expression of the antiapoptotic proteins Bcl2, BclxL and induced myeloid leukaemia cell differentiation protein Mcl1, and increasing the expression of the proapoptotic proteins Bax and Bad, cleaved caspased3 and poly(ADP)ribose polymerase. These findings suggested that RPMTG induced apoptosis through mitochondrialrelated pathways. In addition, RPMTG also decreased the expression of phosphorylated (p)extracellular signalregulated kinase and increased pcJun Nterminal kinase (pJNK) and pp38. Moreover, the effects of RPMTG on cell proliferation and apoptosis were partially reversed when the JNK and p38 mitogenactivated protein kinase (MAPK) pathways were inhibited, indicating that RPMTG triggered apoptosis mainly via regulating JNK and p38 MAPK signalling. Therefore, RPMTG may have potential as an antiCRC agent, and further evaluations are needed.
Assuntos
Neoplasias Colorretais/patologia , Medicamentos de Ervas Chinesas/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Panax/química , Rizoma/química , Saponinas/farmacologia , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/tratamento farmacológico , Medicamentos de Ervas Chinesas/isolamento & purificação , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Mitocondriais/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Saponinas/isolamento & purificação , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidoresRESUMO
2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is a persistent organic pollutant that is strongly associated with a number of human diseases and birth defects, including cleft palate. Transforming growth factor (TGF) plays a significant role during mammalian palatogenesis. However, the epigenetic mechanism of transforming growth factors in the process of TCDD-induced cleft palate is unclear. The purpose of this research was to investigate the relationship and potential mechanism between TGF-ß2/3 promoter DNA methylation and Smad signaling during TCDD-induced cleft palate. Pregnant C57BL/6N mice were exposed to 64 µg/kg TCDD on gestational day 10 (GD10) to establish the cleft palate model and palatal tissues of embryos were collected on GD13, GD14, and GD15 for subsequent experiments. TGF-ß2/3 mRNA expression, TGF-ß2/3 promoter methylation, and Smad signaling molecules expression were assessed in the palate of the two groups. The results showed that the incidence of cleft palate was 94.7% in the TCDD-treated group whereas no cleft palate was found in the control group. TCDD-treated group altered specific CpG sites of TGF-ß2/3 promoter methylation. Compared to the control group, the proliferation of mouse embryonic palate mesenchymal stromal cells (MEPM), the expressions of TGF-ß2/3, p-Smad2, and Smad4 were all reduced, while the expression of Smad7 was significantly increased in the atAR group. Smad signaling was downregulated by TCDD. Therefore, we suggest that TGF-ß2/3 promoter methylation and Smad signaling may be involved in TCDD-induced cleft palate formation in fetal mice.
Assuntos
Proteínas Reguladoras de Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Metilação de DNA/efeitos dos fármacos , Proteínas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Dibenzodioxinas Policloradas/farmacologia , Animais , Regulação para Baixo , Camundongos Endogâmicos C57BL , Palato/efeitos dos fármacos , Dibenzodioxinas Policloradas/metabolismo , Regiões Promotoras Genéticas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta2/genética , Fator de Crescimento Transformador beta2/metabolismoRESUMO
Tissue accumulation and high urinary excretion of ethylmalonic acid (EMA) are found in ethylmalonic encephalopathy (EE), an inherited disorder associated with cerebral and cerebellar atrophy whose pathogenesis is poorly established. The in vitro and in vivo effects of EMA on bioenergetics and redox homeostasis were investigated in rat cerebellum. For the in vitro studies, cerebellum preparations were exposed to EMA, whereas intracerebellar injection of EMA was used for the in vivo evaluation. EMA reduced state 3 and uncoupled respiration in vitro in succinate-, glutamate-, and malate-supported mitochondria, whereas decreased state 4 respiration was observed using glutamate and malate. Furthermore, mitochondria permeabilization and succinate supplementation diminished the decrease in state 3 with succinate. EMA also inhibited the activity of KGDH, an enzyme necessary for glutamate oxidation, in a mixed manner and augmented mitochondrial efflux of α-ketoglutarate. ATP levels were markedly reduced by EMA, reflecting a severe bioenergetic disruption. Docking simulations also indicated interactions between EMA and KGDH and a competition with glutamate and succinate for their mitochondrial transporters. In vitro findings also showed that EMA decreased mitochondrial membrane potential and Ca2+ retention capacity, and induced swelling in the presence of Ca2+ , which were prevented by cyclosporine A and ADP and ruthenium red, indicating mitochondrial permeability transition (MPT). Moreover, EMA, at high concentrations, mildly increased ROS levels and altered antioxidant defenses in vitro and in vivo. Our data indicate that EMA-induced impairment of glutamate and succinate oxidation and MPT may contribute to the pathogenesis of the cerebellum abnormalities in EE.
Assuntos
Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Metabolismo Energético/efeitos dos fármacos , Glutamatos/metabolismo , Malonatos/toxicidade , Poro de Transição de Permeabilidade Mitocondrial , Succinatos/metabolismo , Animais , Ácidos Cetoglutáricos/metabolismo , Malatos/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Simulação de Acoplamento Molecular , Oxirredução , Consumo de Oxigênio/efeitos dos fármacos , Ratos , Ratos Wistar , Succinatos/farmacologiaRESUMO
Mitophagy, the elimination of damaged mitochondria through autophagy, promotes neuronal survival in cerebral ischemia. Previous studies found deficient mitophagy in ischemic neurons, but the mechanisms are still largely unknown. We determined that BNIP3L/NIX, a mitophagy receptor, was degraded by proteasomes, which led to mitophagy deficiency in both ischemic neurons and brains. BNIP3L exists as a monomer and homodimer in mammalian cells, but the effects of homodimer and monomer on mitophagy are unclear. Site-specific mutations in the transmembrane domain of BNIP3L (S195A and G203A) only formed the BNIP3L monomer and failed to induce mitophagy. Moreover, overexpression of wild-type BNIP3L, in contrast to the monomeric BNIP3L, rescued the mitophagy deficiency and protected against cerebral ischemic injury. The macroautophagy/autophagy inhibitor 3-MA and the proteasome inhibitor MG132 were used in cerebral ischemic brains to identify how BNIP3L was reduced. We found that MG132 blocked the loss of BNIP3L and subsequently promoted mitophagy in ischemic brains. In addition, the dimeric form of BNIP3L was more prone to be degraded than its monomeric form. Carfilzomib, a drug for multiple myeloma therapy that inhibits proteasomes, reversed the BNIP3L degradation and restored mitophagy in ischemic brains. This treatment protected against either acute or chronic ischemic brain injury. Remarkably, these effects of carfilzomib were abolished in bnip3l-/- mice. Taken together, the present study linked BNIP3L degradation by proteasomes with mitophagy deficiency in cerebral ischemia. We propose carfilzomib as a novel therapy to rescue ischemic brain injury by preventing BNIP3L degradation.Abbreviations: 3-MA: 3-methyladenine; AAV: adeno-associated virus; ATG7: autophagy related 7; BCL2L13: BCL2-like 13 (apoptosis facilitator); BNIP3L/NIX: BCL2/adenovirus E1B interacting protein 3-like; CCCP: carbonyl cyanide 3-chlorophenylhydrazone; CFZ: carfilzomib; COX4I1: cytochrome c oxidase subunit 4I1; CQ: chloroquine; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GFP: green fluorescent protein; I-R: ischemia-reperfusion; MAP1LC3A/LC3A: microtube-associated protein 1 light chain 3 alpha; MAP1LC3B/LC3B: microtube-associated protein 1 light chain 3 beta; O-R: oxygen and glucose deprivation-reperfusion; OGD: oxygen and glucose deprivation; PHB2: prohibitin 2; pMCAO: permanent middle cerebral artery occlusion; PRKN/PARK2: parkin RBR E3 ubiquitin protein ligase; PT: photothrombosis; SQSTM1: sequestosome 1; tMCAO: transient middle cerebral artery occlusion; TOMM20: translocase of outer mitochondrial membrane 20; TTC: 2,3,5-triphenyltetrazolium hydrochloride.
Assuntos
Autofagia/efeitos dos fármacos , Isquemia/tratamento farmacológico , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/metabolismo , Mitofagia/efeitos dos fármacos , Oligopeptídeos/farmacologia , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Autofagia/fisiologia , Isquemia/metabolismo , Proteínas de Membrana/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/efeitos dos fármacos , Mitofagia/genética , Espécies Reativas de Oxigênio/metabolismoRESUMO
BACKGROUND: Alzheimer's disease (AD) is characterized by accumulation of amyloid-ß (Aß) species and deposition of senile plaques (SPs). Clinical trials with the anti-Aß antibody aducanumab have been completed recently. OBJECTIVE: To characterize the proteomic profile of SPs and surrounding tissue in a mouse model of AD in 10-month-old tgAPPPS1-21 mice after chronic treatment with aducanumab for four months with weekly dosing (10âmg/kg). METHODS: After observing significant reduction of SP numbers in hippocampi of aducanumab-treated mice, we applied a localized proteomic analysis by combining laser microdissection and liquid chromatography-tandem mass spectrometry (LC-MS/MS) of the remaining SPs in hippocampi. We microdissected three subregions, containing SPs, SP penumbra level 1, and an additional penumbra level 2 to follow the proteomic profile as gradient. RESULTS: In the aducanumab-treated mice, we identified 17 significantly regulated proteins that were associated with 1) mitochondria and metabolism (ACAT2, ATP5J, ETFA, EXOG, HK1, NDUFA4, NDUFS7, PLCB1, PPP2R4), 2) cytoskeleton and axons (ADD1, CAPZB, DPYSL3, MAG), 3) stress response (HIST1H1C/HIST1H1D, HSPA12A), and 4) AßPP trafficking/processing (CD81, GDI2). These pathways and some of the identified proteins are implicated in AD pathogenesis. Proteins associated with mitochondria and metabolism were mainly upregulated while proteins associated with AßPP trafficking/processing and stress response pathways were mainly downregulated, suggesting that aducanumab could lead to a beneficial proteomic profile around SPs in tgAPPPS1-21 mice. CONCLUSION: We identified novel proteomic patterns of SPs and surrounding tissue indicating that chronic treatment with aducanumab could inhibit Aß toxicity and increase phagocytosis and cell viability.
Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/efeitos dos fármacos , Precursor de Proteína beta-Amiloide/metabolismo , Anticorpos Monoclonais Humanizados/farmacologia , Encéfalo/efeitos dos fármacos , Placa Amiloide/metabolismo , Proteoma/efeitos dos fármacos , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Encéfalo/metabolismo , Cromatografia Líquida , Proteínas do Citoesqueleto/efeitos dos fármacos , Proteínas do Citoesqueleto/metabolismo , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Transgênicos , Proteínas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Presenilina-1/genética , Transporte Proteico/efeitos dos fármacos , Proteômica , Estresse Fisiológico/efeitos dos fármacos , Espectrometria de Massas em TandemRESUMO
Brain is a fully differentiated organ and is sensitive towards oxidative damage of various compounds including lipids, proteins, and DNA that occurs during process of normal aging and is mainly due to its high energy metabolism and reduced activity of anti-oxidative defense mechanism. Mitochondria are dynamic ATP-generating organelles which constitutes cellular functions such as regulation of intracellular calcium, bio-energetic processes, and reduction-oxidation of cells. Such functioning is negatively affected due to the presence of amyloid ß peptide (Aß) which is involved in pathogenesis of Alzheimer disease (AD). Aß interacts with mitochondria and leads to mitochondrial dysfunction. Mitochondrial dysfunction, abnormal interactions, oxidative stress, and mis-folding of synaptic proteins inside nervous system are explored and regarded as primary or initial features in insurgence of pathology (AD and other neurological disease). The major histopathological hallmarks of AD are characterized by presence of these hallmarks intracellularly, its further progression and exacerbation which leads to excessive accumulation of oligomeric as well as fibrillar-ß-amyloid peptides (present extracellularly) and accumulation of neurofibrillary tangles intracellularly. The current review will focus on alterations and variation in mitochondria/mitochondrial DNA (mtDNA) and the rationale for involvement of related abnormalities in pathogenesis of AD.
Assuntos
Doença de Alzheimer/genética , Mitocôndrias/patologia , Proteínas Mitocondriais/genética , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Progressão da Doença , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Proteínas Mitocondriais/efeitos dos fármacos , Terapia de Alvo Molecular , Estresse Oxidativo/efeitos dos fármacosRESUMO
Exposure to arsenic is a risk factor for nonalcoholic steatohepatitis (NASH). Ferroptosis is a form of regulated cell death defined by the accumulation of lipid peroxidation. In the current study, we observed the occurrence of ferroptosis in arsenic-induced NASH by assessing ferroptosis related hallmarks. In vitro, we found that ferrostatin-1 effectively attenuated the executing of ferroptosis and NASH. Simultaneously, the expression of ACSL4 (acyl-CoA synthetase long-chain family member 4) was upregulated in rat's liver and L-02 cells exposed to arsenic. While, suppression of ACSL4 with rosiglitazone or ACSL4 siRNA remarkably alleviated arsenic-induced NASH and ferroptosis through diminishing 5-hydroxyeicosatetraenoic acid (5-HETE) content. Additionally, Mitofusin 2 (Mfn2), a physical tether between endoplasmic reticulum and mitochondria, has rarely been explored in the ferroptosis. Using Mfn2 siRNA or inositol-requiring enzyme 1 alpha (IRE1α) inhibitor, we found NASH and ferroptosis were obviously mitigated through reducing 5-HETE content. Importantly, Co-IP assay indicated that Mfn2 could interact with IRE1α and promoted the production of 5-HETE, ultimately led to ferroptosis and NASH. Collectively, our data showed that ferroptosis is involved in arsenic-induced NASH. These data provide insightful viewpoints into the mechanism of arsenic-induced NASH.
Assuntos
Arsênio , Hepatopatia Gordurosa não Alcoólica , Animais , Arsênio/toxicidade , Coenzima A Ligases , Endorribonucleases/efeitos dos fármacos , Endorribonucleases/fisiologia , Ferroptose , GTP Fosfo-Hidrolases/efeitos dos fármacos , GTP Fosfo-Hidrolases/fisiologia , Proteínas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/fisiologia , Complexos Multienzimáticos/efeitos dos fármacos , Complexos Multienzimáticos/fisiologia , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Proteínas Serina-Treonina Quinases/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/fisiologia , RatosRESUMO
Sirtuin (SIRT) is known to prevent nonalcoholic fatty liver disease (NAFLD); however, the role of SIRT4 in the progression of hepatic fibrosis remains unknown. We hypothesize that EX-527, a selective SIRT1 inhibitor, can inhibit the progression of high-fat diet (HFD)-induced hepatic fibrosis. We found that SIRT4 expression in the liver of NAFLD patients is significantly lower than that in normal subjects. In this study, EX-527 (5 µg/kg), administered to HFD rats twice a week for ten weeks, reduced the serum levels of triglyceride (TG), total cholesterol, alanine aminotransferase (ALT), and aspartate aminotransferase (AST) and attenuated hepatic fibrosis evidenced by Masson's trichrome and hepatic fat by oil red-O staining. EX-527 upregulated SIRT2, SIRT3, and SIRT4 expression in the liver of HFD fed rats but downregulated transforming growth factor-ß1 (TGF-ß1) and α-smooth muscle actin (α-SMA) expression. It decreased proinflammatory cytokine production and hydroxyproline levels in the serum and SMAD4 expression and restored apoptotic protein (Bcl-2, Bax, and cleaved caspase-3) expression. These data propose a critical role for the SIRT4/SMAD4 axis in hepatic fibrogenesis. SIRT4 upregulation has the potential to counter HFD-induced lipid accumulation, inflammation, and fibrogenesis. We demonstrate that EX-527 is a promising candidate in inhibiting the progression of HFD-induced liver fibrosis.
Assuntos
Carbazóis/farmacologia , Dieta Hiperlipídica/efeitos adversos , Cirrose Hepática/prevenção & controle , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Ração Animal , Animais , Aspartato Aminotransferases/efeitos dos fármacos , Progressão da Doença , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico , Proteínas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Ratos , Ratos ZuckerRESUMO
Aiming to promote cancer cell apoptosis is a mainstream strategy of cancer therapy. The second mitochondria-derived activator of caspase (SMAC)/direct inhibitor of apoptosis protein (IAP)-binding protein with low pI (DIABLO) protein is an essential and endogenous antagonist of inhibitor of apoptosis proteins (IAPs). SMAC mimetics (SMs) are a series of synthetically chemical compounds. Via database analysis and literature searching, we summarize the potential mechanisms of endogenous SMAC inefficiency, degradation, mutation, releasing blockage, and depression. We review the development of SMs, as well as preclinical and clinical outcomes of SMs in solid tumor treatment, and we analyze their strengths, weaknesses, opportunities, and threats from our point of view. We also highlight several questions in need of further investigation.
Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Proteínas Inibidoras de Apoptose/farmacologia , Mitocôndrias/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Neoplasias/tratamento farmacológico , Animais , Proteínas Reguladoras de Apoptose/efeitos dos fármacos , Caspases/efeitos dos fármacos , Caspases/metabolismo , Humanos , Proteínas Inibidoras de Apoptose/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/efeitos dos fármacos , Neoplasias/metabolismoRESUMO
Mitochondrial dysfunction has been thought to play roles in the pathogenesis of diabetic nephropathy (DN). However, precise mechanisms underlying mitochondrial dysfunction in DN remained unclear. Herein, mitochondria were isolated from renal tubular cells after exposure to normal glucose (5.5 mM glucose), high glucose (25 mM glucose), or osmotic control (5.5 mM glucose + 19.5 mM mannitol) for 96 h. Comparative proteomic analysis revealed six differentially expressed proteins among groups that were subsequently identified by tandem mass spectrometry (nanoLC-ESI-ETD MS/MS) and confirmed by Western blotting. Several various types of post-translational modifications (PTMs) were identified in all of these identified proteins. Interestingly, phosphorylation and oxidation were most abundant in mitochondrial proteins whose levels were exclusively increased in high glucose condition. The high glucose-induced increases in phosphorylation and oxidation of mitochondrial proteins were successfully confirmed by various assays including MS/MS analyses. Moreover, high glucose also increased levels of phosphorylated ezrin, intracellular ATP and ROS, all of which could be abolished by a p38 MAPK inhibitor (SB239063), implicating a role of p38 MAPK-mediated phosphorylation in high glucose-induced mitochondrial dysfunction. These data indicate that phosphorylation and oxidation of mitochondrial proteins are, at least in part, involved in mitochondrial dysfunction in renal tubular cells during DN.
Assuntos
Glucose/farmacologia , Túbulos Renais/efeitos dos fármacos , Proteínas Mitocondriais/efeitos dos fármacos , Animais , Western Blotting , Cães , Túbulos Renais/metabolismo , Células Madin Darby de Rim Canino/efeitos dos fármacos , Células Madin Darby de Rim Canino/metabolismo , Espectrometria de Massas , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Oxirredução/efeitos dos fármacos , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Proteômica/métodosRESUMO
Purpose: Evidence has shown that propofol may cause widespread apoptotic neurodegeneration. Hypoxic preconditioning has been demonstrated to provide neuroprotection and brain recovery from both acute and chronic neurodegeneration in several cellular and animal models. However, the mechanism has not been well elucidated. Therefore, the present study was designed to investigate the expression of glucose transporters (GLUT1 and GLUT3) and mitochondrial division and fusion (Drp1 and Mfn2) proteins in rats exposed to hypoxic preconditioning to attenuate propofol neurotoxicity.Methods: Propofol (100 mg/kg) was given to 7-day-old Sprague-Dawley rats; in some rats, hypoxic preconditioning was administered before intraperitoneal propofol injection by subjecting rats to five cycles of 10 min of hypoxia (8% O2) and 10 min of normoxia (21% O2). Then, the rats were allowed to breathe room air for 2 h. Neuronal mitochondrial morphology was observed by transmission electron microscopy. ATP content was detected using an ATP assay kit. The expression levels of GLUT1, GLUT3, pDrp1, Drp1 and Mfn2 were detected by Western blot, and the expression levels of GLUT1 and GLUT3 were further examined by immunohistochemistry.Results: Propofol damaged mitochondria, and decreased ATP content and GLUT3 and pDrp1 protein expression. However, our results suggested that hypoxic preconditioning could attenuate propofol neurotoxicity by reducing mitochondrial damage and increasing ATP content and pDrp1, GLUT1 and GLUT3 protein expression.Conclusion: Hypoxic preconditioning reduced propofol-induced damage in the hippocampus of neonatal rats by attenuating the increase in mitochondrial division and decrease in GLUT3 expression.
Assuntos
Dinaminas , GTP Fosfo-Hidrolases , Transportador de Glucose Tipo 1 , Transportador de Glucose Tipo 3 , Hipocampo , Hipnóticos e Sedativos/toxicidade , Hipóxia Encefálica , Mitocôndrias , Proteínas Mitocondriais , Neurônios , Síndromes Neurotóxicas/prevenção & controle , Propofol/toxicidade , Animais , Animais Recém-Nascidos , Modelos Animais de Doenças , Dinaminas/efeitos dos fármacos , Dinaminas/metabolismo , GTP Fosfo-Hidrolases/efeitos dos fármacos , GTP Fosfo-Hidrolases/metabolismo , Transportador de Glucose Tipo 1/efeitos dos fármacos , Transportador de Glucose Tipo 1/metabolismo , Transportador de Glucose Tipo 3/efeitos dos fármacos , Transportador de Glucose Tipo 3/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipnóticos e Sedativos/administração & dosagem , Hipóxia Encefálica/metabolismo , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Propofol/administração & dosagem , Ratos , Ratos Sprague-DawleyRESUMO
Thallium ion (Tl+) and its neurotoxic products are widely known to cause severe neurological complications. However, the exact mechanism of action remains unknown, with limited therapeutic options available. This study aims to examine the toxic effects of Thallium (I) Nitrate (TlNO3) on primary hippocampal neurons of E17-E18 Wistar rat embryos, and the potential neuroprotective role of Nrf2- Keap1 signaling pathway against thallium-induced oxidative stress and mitochondrial dysfunction. TlNO3 induces a significant increase in reactive oxygen species levels and mitochondrial dysfunction in primary hippocampal neurons. Furthermore, the Nrf2-Keap1 signaling pathway played a protective role against TlNO3-induced hippocampal neuronal cytotoxicity. Moreover, mitochondrial fusion protein Mitofusin 2 (Mfn2) levels significantly decreased in hippocampal neurons when exposed to TlNO3, indicating that Mfn2 protein levels are linked to TlNO3-induced neurotoxicity. t-BHQ, a Nrf2 and phase II detoxification enzyme inducer, counteracted the oxidative damage in hippocampal neurons by activating the Nrf2-Keap1 signaling pathway after TlNO3 exposure; the activated Nrf2-Keap1 pathway could then maintain Mfn2 function by regulating Mfn2 protein expression. Thus, Nrf2-Keap1 pathway activation plays a protective role in Tl+-induced brain damage, and specific agonists have been identified to have great potential for treating thallium poisoning.
Assuntos
Hipocampo/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Tálio/toxicidade , Animais , Encefalopatias/induzido quimicamente , Encefalopatias/patologia , Encefalopatias/prevenção & controle , Feminino , GTP Fosfo-Hidrolases , Hipocampo/citologia , Proteínas de Membrana/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Proteínas Mitocondriais/efeitos dos fármacos , Proteínas Mitocondriais/metabolismo , Cultura Primária de Células , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismoRESUMO
Clenbuterol induces a slow-to-fast fiber type transition in skeletal muscle. This muscle fiber transition decreased mitochondrial oxidative capacity and respiratory function. We hypothesized that the clenbuterol-mediated reduction in oxidative capacity is associated with the alteration in mitochondrial morphology. To verify this hypothesis, we examined whether clenbuterol alters mitochondrial morphology and mitochondrial regulatory proteins in rat skeletal muscle. Clenbuterol was administered to rats via drinking water (30 mg/L) for 3 weeks. Myosin heavy chain (MHC) isoform composition, mitochondrial morphology, and fusion and fission regulatory protein levels in deep region and superficial region in tibialis anterior (TA) muscles were assessed. Clenbuterol induced the fiber type transition from slow to fast in both the regions of TA. The levels of optic atrophy protein 1, mitofusin 2, and mitochondrial fission 1, but not of dynamin-related protein 1, significantly decreased in deep and superficial muscles after clenbuterol administration (P < 0.01). Also, observation using the transmission electron microscopy showed a decrease in mitochondrial volume (P < 0.05) and an increase in proportion of continuous or interacting mitochondria across Z-lines (P < 0.05). We showed that clenbuterol administration induces a transition in the muscle fiber type composition toward fast phenotype and causes alterations in mitochondrial morphology with a concomitant decrease in mitochondrial fusion and fission regulatory protein levels. These mitochondrial morphological alterations may influence deleterious effects on skeletal muscle metabolism.
Assuntos
Agonistas Adrenérgicos beta/toxicidade , Clembuterol/toxicidade , Mitocôndrias/efeitos dos fármacos , Proteínas Mitocondriais/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Animais , Masculino , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Músculo Esquelético/metabolismo , Ratos , Ratos WistarRESUMO
Ochratoxin A (OTA) is a mycotoxin ubiquitous in feeds and foodstuffs. The water-insoluble pentacyclic triterpene bioactive compound, ursolic acid (UA), is widespread in various cuticular waxes of edible fruits, food materials, and medicinal plants. Although studies have reported that oxidative stress was involved in both the nephrotoxicity of OTA and the renoprotective function of UA, the role of stress-responsive Lon protease 1 (Lonp1) in the renoprotection of UA against OTA is still unknown. In this study, cell viability, reactive oxygen species (ROS) production, and several proteins' expressions of human embryonic kidney 293T (HEK293T) cells in response to UA, OTA, and/or Lonp1 inhibitor CDDO-me treatment were detected to reveal the protective mechanism of UA against OTA-induced renal cytotoxicity. Results indicated that a 2 h-treatment of 1⯵M UA could significantly alleviate the ROS production and cell death induced by a 24 h-treatment of 8⯵M OTA in HEK293T cells (Pâ¯<â¯0.05). Compared with the control, the protein expressions of Lonp1, Aco2 and Hsp75 were significantly inhibited after 8⯵M OTA treating for 24â¯h (Pâ¯<â¯0.05), which could be notably reversed by the pre-treatment and post-treatment of 1⯵M UA (Pâ¯<â¯0.05). The protein expressions of Lonp1, Aco2 and Hsp75 were inhibited by the addition of CDDO-me. The three protein expression trends were similar before and after the addition of CDDO-me. In conclusion, OTA could inhibit the expression of Lonp1, suppressing Aco2 and Hsp75 as a result, thereby activating ROS and inducing cell death in HEK293T cells, which could be alleviated by UA pre-treatment.