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1.
Brain Nerve ; 73(4): 359-367, 2021 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-33824223

RESUMO

Although the involvement of genomic factors in bipolar disorder is clear, its neural basis remains a question. We proposed the mitochondrial dysfunction hypothesis of bipolar disorder in 2000 and have since been testing it. Our results showed that mitochondrial DNA (mtDNA) polymorphisms affected mitochondrial Ca2+ concentration, and mitochondrial Ca2+ uptake and intracellular Ca2+ signaling were altered. Spontaneous repetitive depressive episodes were seen in mice in which mtDNA mutations accumulated in the brain (mutant Polg transgenic mice). We searched for the brain regions with the accumulation of mutant mtDNA in these mice, and found that it was most abundant in the paraventricular nucleus of the thalamus (PVT). Neural circuit manipulation of the PVT caused similar repetitive hypoactive episodes, suggesting that the PVT may be involved in causing bipolar disorder.


Assuntos
Transtorno Bipolar , Animais , Transtorno Bipolar/genética , Encéfalo/metabolismo , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Camundongos , Camundongos Transgênicos , Mitocôndrias/genética
2.
Adv Exp Med Biol ; 1286: 65-76, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33725345

RESUMO

Mitochondrial bioenergetics is vital for the proper functioning of cellular compartments. Impairments in mitochondrial DNA encoding the respiratory chain complexes and other assisting proteins, accumulation of intracellular reactive oxygen species, an imbalance in cellular calcium transport, or the presence of organic pollutants, high fat-ketogenic diets or toxins, and advancing age can result in complex disorders, including cancer, metabolic disease, and neurodegenerative disorders. Such manifestations are distinctly exhibited in several age-related neurodegenerative diseases, such as in Parkinson's disease (PD). Defects in complex I along with perturbed signaling pathways is a common manifestation of PD. Impaired oxidative phosphorylation could increase the susceptibility to PD. Therefore, unraveling the mechanisms of mitochondrial complexes in clinical scenarios will assist in developing potential early biomarkers and standard tests for energy failure diagnosis and assist to pave a new path for targeted therapeutics against PD.


Assuntos
Doença de Parkinson , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Humanos , Mitocôndrias/metabolismo , Fosforilação Oxidativa , Doença de Parkinson/genética , Doença de Parkinson/metabolismo
3.
Science ; 371(6535)2021 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-33542149

RESUMO

The cyclic guanosine monophosphate (GMP)-adenosine monophosphate (AMP) synthase (cGAS) detects microbial and self-DNA in the cytosol to activate immune and inflammatory programs. cGAS also associates with chromatin, especially after nuclear envelope breakdown when cells enter mitosis. How cGAS is regulated during cell cycle transition is not clear. Here, we found direct biochemical evidence that cGAS activity was selectively suppressed during mitosis in human cell lines and uncovered two parallel mechanisms underlying this suppression. First, cGAS was hyperphosphorylated at the N terminus by mitotic kinases, including Aurora kinase B. The N terminus of cGAS was critical for sensing nuclear chromatin but not mitochondrial DNA. Chromatin sensing was blocked by hyperphosphorylation. Second, oligomerization of chromatin-bound cGAS, which is required for its activation, was prevented. Together, these mechanisms ensure that cGAS is inactive when associated with chromatin during mitosis, which may help to prevent autoimmune reaction.


Assuntos
Cromatina/metabolismo , Mitose , Nucleotidiltransferases/metabolismo , Aurora Quinase B/metabolismo , Ciclo Celular , Linhagem Celular , DNA/metabolismo , DNA Mitocondrial/metabolismo , Ativação Enzimática , Humanos , Nucleotídeos Cíclicos/metabolismo , Nucleotidiltransferases/química , Fosforilação , Multimerização Proteica
4.
Int J Mol Sci ; 22(4)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562258

RESUMO

Calorie restriction (CR) is the most efficacious treatment to delay the onset of age-related changes such as mitochondrial dysfunction. However, the sensitivity of mitochondrial markers to CR and the age-related boundaries of CR efficacy are not fully elucidated. We used liver samples from ad libitum-fed (AL) rats divided in: 18-month-old (AL-18), 28-month-old (AL-28), and 32-month-old (AL-32) groups, and from CR-treated (CR) 28-month-old (CR-28) and 32-month-old (CR-32) counterparts to assay the effect of CR on several mitochondrial markers. The age-related decreases in citrate synthase activity, in TFAM, MFN2, and DRP1 protein amounts and in the mtDNA content in the AL-28 group were prevented in CR-28 counterparts. Accordingly, CR reduced oxidative mtDNA damage assessed through the incidence of oxidized purines at specific mtDNA regions in CR-28 animals. These findings support the anti-aging effect of CR up to 28 months. Conversely, the protein amounts of LonP1, Cyt c, OGG1, and APE1 and the 4.8 Kb mtDNA deletion content were not affected in CR-28 rats. The absence of significant differences between the AL-32 values and the CR-32 counterparts suggests an age-related boundary of CR efficacy at this age. However, this only partially curtails the CR benefits in counteracting the generalized aging decline and the related mitochondrial involvement.


Assuntos
Envelhecimento , Restrição Calórica/efeitos adversos , DNA Mitocondrial/metabolismo , Fígado/patologia , Mitocôndrias/patologia , Biogênese de Organelas , Estresse Oxidativo , Animais , DNA Mitocondrial/genética , Fígado/metabolismo , Masculino , Mitocôndrias/genética , Mitocôndrias/metabolismo , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos F344
5.
Life Sci ; 268: 118936, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33421523

RESUMO

AIMS: During oxidative stress mitochondria become the main source of endogenous reactive oxygen species (ROS) production. In the present study, we aimed to clarify the effects of pharmacological PARP-1 inhibition on mitochondrial function and quality control processes. MAIN METHODS: L-2286, a quinazoline-derivative PARP inhibitor, protects against cardiovascular remodeling and heart failure by favorable modulation of signaling routes. We examined the effects of PARP-1 inhibition on mitochondrial quality control processes and function in vivo and in vitro. Spontaneously hypertensive rats (SHRs) were treated with L-2286 or placebo. In the in vitro model, 150 µM H2O2 stress was applied on neonatal rat cardiomyocytes (NRCM). KEY FINDINGS: PARP-inhibition prevented the development of left ventricular hypertrophy in SHRs. The interfibrillar mitochondrial network were less fragmented, the average mitochondrial size was bigger and showed higher cristae density compared to untreated SHRs. Dynamin related protein 1 (Drp1) translocation and therefore the fission of mitochondria was inhibited by L-2286 treatment. Moreover, L-2286 treatment increased the amount of fusion proteins (Opa1, Mfn2), thus preserving structural stability. PARP-inhibition also preserved the mitochondrial genome integrity. In addition, the mitochondrial biogenesis was also enhanced due to L-2286 treatment, leading to an overall increase in the ATP production and improvement in survival of stressed cells. SIGNIFICANCE: Our results suggest that the modulation of mitochondrial dynamics and biogenesis can be a promising therapeutical target in hypertension-induced myocardial remodeling and heart failure.


Assuntos
Hipertensão/fisiopatologia , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Mitocôndrias Cardíacas/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Animais , Células Cultivadas , Citrato (si)-Sintase/metabolismo , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Eletrocardiografia , Glutationa/metabolismo , Hipertrofia Ventricular Esquerda/etiologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Mitocôndrias Cardíacas/ultraestrutura , Proteínas Mitocondriais/metabolismo , Miócitos Cardíacos/patologia , Peptídeo Natriurético Encefálico/sangue , Piperidinas/farmacologia , Quinazolinas/farmacologia , Ratos Endogâmicos SHR , Ratos Wistar
6.
AAPS PharmSciTech ; 22(1): 18, 2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33389284

RESUMO

Engineered cell-derived extracellular vesicles (EVs) such as exosomes and microvesicles hold immense potential as safe and efficient drug carriers due to their lower immunogenicity and inherent homing capabilities to target cells. In addition to innate vesicular cargo such as lipids, proteins, and nucleic acids, EVs are also known to contain functional mitochondria/mitochondrial DNA that can be transferred to recipient cells to increase cellular bioenergetics. In this proof-of-concept study, we isolated naïve EVs and engineered EVs loaded with an exogenous plasmid DNA encoding for brain-derived neurotrophic factor (BDNF-EVs) from hCMEC/D3, a human brain endothelial cell line, and RAW 264.7 macrophages. We tested whether mitochondrial components in naïve or engineered EVs can increase ATP levels in the recipient brain endothelial cells. EVs (e.g., exosomes and microvesicles; EXOs and MVs) were isolated from the conditioned medium of either untreated (naïve) or pDNA-transfected (Luc-DNA or BDNF-DNA) cells using a differential centrifugation method. RAW 264.7 cell line-derived EVs showed a significantly higher DNA loading and increased luciferase expression in the recipient hCMEC/D3 cells at 72 h compared with hCMEC/D3 cell line-derived EVs. Naïve EVs from hCMEC/D3 cells and BDNF-EVs from RAW 264.7 cells showed a small, but a significantly greater increase in the ATP levels of recipient hCMEC/D3 cells at 24 and 48 h post-exposure. In summary, we have demonstrated (1) differences in exogenous pDNA loading into EVs as a function of cell type using brain endothelial and macrophage cell lines and (2) EV-mediated increases in the intracellular ATP levels in the recipient hCMEC/D3 monolayers.


Assuntos
Trifosfato de Adenosina/metabolismo , Encéfalo/metabolismo , Células Endoteliais/metabolismo , Vesículas Extracelulares/metabolismo , Animais , Encéfalo/citologia , Linhagem Celular , DNA Mitocondrial/metabolismo , Portadores de Fármacos , Metabolismo Energético , Humanos , Camundongos , Estudo de Prova de Conceito , Células RAW 264.7
7.
Environ Pollut ; 270: 116242, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33321436

RESUMO

The immune system is one of the primary targets of airborne particulate matter. Recent evidence suggests that mitochondria lie at the center of particulate matter-induced immunotoxicity. Particulate matter can directly interact with mitochondrial components (proteins, lipids, and nucleic acids) and impairs the vital mitochondrial processes including redox mechanisms, fusion-fission, autophagy, and metabolic pathways. These disturbances impede different mitochondrial functions including ATP production, which acts as an important platform to regulate immunity and inflammatory responses. Moreover, the mitochondrial DNA released into the cytosol or in the extracellular milieu acts as a danger-associated molecular pattern and triggers the signaling pathways, involving cGAS-STING, TLR9, and NLRP3. In the present review, we discuss the emerging role of mitochondria in airborne particulate matter-induced immunotoxicity and its myriad biological consequences in health and disease.


Assuntos
Mitocôndrias , Material Particulado , Autofagia , DNA Mitocondrial/metabolismo , Mitocôndrias/metabolismo , Oxirredução , Material Particulado/metabolismo , Material Particulado/toxicidade
8.
Methods Mol Biol ; 2192: 21-34, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33230762

RESUMO

Single molecule analysis of replicating DNA (SMARD) is a powerful methodology that allows in vivo analysis of replicating DNA; identification of origins of replication, assessment of fork directionality, and measurement of replication fork speed. SMARD, which has been extensively used to study replication of nuclear DNA, involves incorporation of thymidine analogs to nascent DNA chains and their subsequent visualization through immune detection. Here, we adapt and fine-tune the SMARD technique to the specifics of human and mouse mitochondrial DNA. The mito-SMARD protocol allows researchers to gain in vivo insight into mitochondrial DNA (mtDNA) replication at the single molecule level and with high resolution.


Assuntos
Replicação do DNA/genética , DNA Mitocondrial/metabolismo , Imagem Individual de Molécula/métodos , Animais , Células Cultivadas , DNA Mitocondrial/genética , Genoma Mitocondrial , Humanos , Hibridização in Situ Fluorescente/métodos , Camundongos , Microscopia de Fluorescência/métodos , Mitocôndrias/metabolismo , Timidina/análogos & derivados , Timidina/metabolismo
9.
Methods Mol Biol ; 2192: 69-73, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33230766

RESUMO

The incorporation of nucleoside analogs is a useful tool to study the various functions of DNA and RNA. These analogs can be detected directly by fluorescence or by immunolabeling, allowing to visualize, track, or measure the nucleic acid molecules in which they have been incorporated. In this chapter, methodologies to measure human mitochondrial transcription are described. The nascent RNA that is transcribed from mitochondrial DNA (mtDNA) has been shown to assemble into large ribonucleoprotein complexes that form discrete foci. These structures were called mitochondrial RNA granules (MRGs) and can be observed in vitro by the incorporation of a 5-Bromouridine (BrU), which is subsequently visualized by fluorescent immunolabeling. Here, a combined protocol for the MRGs detection is detailed, consisting of BrU labeling and visualization of one of their bona fide protein components, Fas-activated serine-threonine kinase domain 2 (FASTKD2). Based on immunodetection, the half-life and kinetics of the MRGs under various experimental conditions can further be determined by chasing the BrU pulse with an excess of Uridine.


Assuntos
Bromouracila/análogos & derivados , Imuno-Histoquímica/métodos , Complexos Multiproteicos/metabolismo , RNA Mitocondrial/metabolismo , Ribonucleoproteínas/metabolismo , Uridina/análogos & derivados , Bromouracila/metabolismo , DNA Mitocondrial/metabolismo , Meia-Vida , Células HeLa , Humanos , Cinética , Complexos Multiproteicos/química , Proteínas Serina-Treonina Quinases/metabolismo , Ribonucleoproteínas/química , Transcrição Genética , Uridina/metabolismo
10.
Nat Commun ; 11(1): 4471, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901010

RESUMO

A human cell contains hundreds to thousands of mitochondrial DNA (mtDNA) packaged into nucleoids. Currently, the segregation and allocation of nucleoids are thought to be passively determined by mitochondrial fusion and division. Here we provide evidence, using live-cell super-resolution imaging, that nucleoids can be actively transported via KIF5B-driven mitochondrial dynamic tubulation (MDT) activities that predominantly occur at the ER-mitochondria contact sites (EMCS). We further demonstrate that a mitochondrial inner membrane protein complex MICOS links nucleoids to Miro1, a KIF5B receptor on mitochondria, at the EMCS. We show that such active transportation is a mechanism essential for the proper distribution of nucleoids in the peripheral zone of the cell. Together, our work identifies an active transportation mechanism of nucleoids, with EMCS serving as a key platform for the interplay of nucleoids, MICOS, Miro1, and KIF5B to coordinate nucleoids segregation and transportation.


Assuntos
DNA Mitocondrial/metabolismo , Retículo Endoplasmático/metabolismo , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/fisiologia , Animais , Transporte Biológico Ativo , Células COS , Células Cultivadas , Chlorocebus aethiops , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Células HEK293 , Humanos , Cinesina/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Membranas Mitocondriais/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Modelos Biológicos , Ratos , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transfecção , Proteínas rho de Ligação ao GTP/metabolismo
11.
Nat Commun ; 11(1): 4289, 2020 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-32855397

RESUMO

Older organs represent an untapped potential to close the gap between demand and supply in organ transplantation but are associated with age-specific responses to injury and increased immunogenicity, thereby aggravating transplant outcomes. Here we show that cell-free mitochondrial DNA (cf-mt-DNA) released by senescent cells accumulates with aging and augments immunogenicity. Ischemia reperfusion injury induces a systemic increase of cf-mt-DNA that promotes dendritic cell-mediated, age-specific inflammatory responses. Comparable events are observed clinically, with the levels of cf-mt-DNA elevated in older deceased organ donors, and with the isolated cf-mt-DNA capable of activating human dendritic cells. In experimental models, treatment of old donor animals with senolytics clear senescent cells and diminish cf-mt-DNA release, thereby dampening age-specific immune responses and prolonging the survival of old cardiac allografts comparable to young donor organs. Collectively, we identify accumulating cf-mt-DNA as a key factor in inflamm-aging and present senolytics as a potential approach to improve transplant outcomes and availability.


Assuntos
DNA Mitocondrial/efeitos adversos , Dasatinibe/farmacologia , Inflamação/prevenção & controle , Transplante de Órgãos/métodos , Quercetina/farmacologia , Adulto , Envelhecimento/fisiologia , Animais , Diferenciação Celular , Ácidos Nucleicos Livres , Senescência Celular/efeitos dos fármacos , Senescência Celular/fisiologia , Citocinas/metabolismo , DNA Mitocondrial/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/fisiologia , Transplante de Coração/efeitos adversos , Transplante de Coração/métodos , Humanos , Inflamação/etiologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Pessoa de Meia-Idade , Transplante de Órgãos/efeitos adversos , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/imunologia , Doadores de Tecidos
12.
PLoS One ; 15(6): e0234745, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32544213

RESUMO

PCR inhibitors are a formidable problem to the study of aged, degraded, and/or low copy number DNA. As a result, there is a need to find alternate methods that ameliorate the efficacy of PCR. In this study, we attempted to use genetic methods to identify the species of salmonid (Oncorhynchus spp.) remains recovered from archaeological sites along the Feather River located in northern California, United States. In the process of doing so, we compared the efficacy of a PCR enhancer cocktail called "PEC-P" and a reagent rich PCR recipe called "rescue PCR" over standard PCR. Across all treatments (full concentration and 1:10 dilute eluates subjected to standard PCR, PEC-P, and rescue PCR) species identification was possible for 74 of 93 archaeological fish specimens (79.6%). Overall, six of the 93 samples (6.5%) consistently yielded species identification across all treatments. The species of ten specimens (10.8%) were uniquely identified from amplicons produced with either PEC-P or rescue PCR or both. Notably, the species of seven samples (7.5%) were uniquely identified with standard PCR over the alternative treatments. Considering both full concentration and 1:10 dilute eluates (N = 186), standard PCR performed as well as PEC-P (p = 0.1451) and rescue (p = 0.6753). Yet, considering results from full concentration eluates alone (N = 93), PEC-P (60.2%) outperformed both standard PCR (44.1%; p = 0.0277) and rescue PCR (40.9%; p = 0.0046). Stochasticity observed in our study cautions us against choosing a "best" performing method of those explored here and suggests their respective potentials to improve success may be sample dependent. When working with samples compromised by PCR inhibitors, it is useful to have alternative methodologies for subduing the problem. Both PEC-P and rescue PCR represent useful alternative methods for the study of aged, degraded, and/or low copy number DNA samples compromised by PCR inhibitors.


Assuntos
DNA/análise , Oncorhynchus/genética , Reação em Cadeia da Polimerase/métodos , Animais , Arqueologia , Osso e Ossos/metabolismo , DNA/metabolismo , DNA Mitocondrial/análise , DNA Mitocondrial/metabolismo , Fatores de Tempo
13.
Life Sci ; 256: 117965, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32544463

RESUMO

BACKGROUND: Several studies have proved that physical activity (PA) regulates energetic metabolism associated with mitochondrial dynamics through AMPK activation in healthy subjects. Obesity, a condition that induces oxidative stress, mitochondrial dysfunction, and low AMPK activity leads to mitochondrial fragmentation. However, few studies describe the effect of PA on mitochondrial dynamics regulation in obesity. AIM: The present study aimed to evaluate the effect of a single session of PA on mitochondrial dynamics regulation as well as its effect on mitochondrial function and organization in skeletal muscles of obese rats (Zucker fa/fa). MAIN METHODS: Male Zucker lean and Zucker fa/fa rats aged 12 to 13 weeks were divided into sedentary and subjected-to-PA (single session swimming) groups. Gastrocnemius muscle was dissected into isolated fibers, mitochondria, mRNA, and total proteins for their evaluation. KEY FINDINGS: The results showed that PA increased the Mfn-2 protein level in the lean and obese groups, whereas Drp1 levels decreased in the obese group. OMA1 protease levels increased in the lean group and decreased in the obese group. Additionally, AMPK analysis parameters (expression, protein level, and activity) did not increase in the obese group. These findings correlated with the partial restoration of mitochondrial function in the obese group, increasing the capacity to maintain the membrane potential after adding calcium as a stressor, and increasing the transversal organization level of the mitochondria analyzed in isolated fibers. SIGNIFICANCE: These results support the notion that obese rats subjected to PA maintain mitochondrial function through mitochondrial fusion activation by an AMPK-independent mechanism.


Assuntos
Mitocôndrias/patologia , Fibras Musculares Esqueléticas/patologia , Obesidade/patologia , Condicionamento Físico Animal , Adenilato Quinase/metabolismo , Animais , Biomarcadores/metabolismo , Citrato (si)-Sintase/metabolismo , DNA Mitocondrial/metabolismo , Regulação da Expressão Gênica , Masculino , Potencial da Membrana Mitocondrial , Dinâmica Mitocondrial , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Tamanho do Órgão , Estresse Oxidativo , Fosforilação , Ratos Zucker
14.
Am J Physiol Cell Physiol ; 319(2): C258-C267, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32510973

RESUMO

Because of the ongoing pandemic around the world, the mechanisms underlying the SARS-CoV-2-induced COVID-19 are subject to intense investigation. Based on available data for the SARS-CoV-1 virus, we suggest how CoV-2 localization of RNA transcripts in mitochondria hijacks the host cell's mitochondrial function to viral advantage. Besides viral RNA transcripts, RNA also localizes to mitochondria. SARS-CoV-2 may manipulate mitochondrial function indirectly, first by ACE2 regulation of mitochondrial function, and once it enters the host cell, open-reading frames (ORFs) such as ORF-9b can directly manipulate mitochondrial function to evade host cell immunity and facilitate virus replication and COVID-19 disease. Manipulations of host mitochondria by viral ORFs can release mitochondrial DNA (mtDNA) in the cytoplasm and activate mtDNA-induced inflammasome and suppress innate and adaptive immunity. We argue that a decline in ACE2 function in aged individuals, coupled with the age-associated decline in mitochondrial functions resulting in chronic metabolic disorders like diabetes or cancer, may make the host more vulnerable to infection and health complications to mortality. These observations suggest that distinct localization of viral RNA and proteins in mitochondria must play essential roles in SARS-CoV-2 pathogenesis. Understanding the mechanisms underlying virus communication with host mitochondria may provide critical insights into COVID-19 pathologies. An investigation into the SARS-CoV-2 hijacking of mitochondria should lead to novel approaches to prevent and treat COVID-19.


Assuntos
Betacoronavirus/genética , Infecções por Coronavirus/virologia , DNA Mitocondrial/genética , Mitocôndrias/genética , Pneumonia Viral/virologia , RNA Viral/genética , Imunidade Adaptativa , Animais , Betacoronavirus/crescimento & desenvolvimento , Betacoronavirus/imunologia , Betacoronavirus/metabolismo , Infecções por Coronavirus/genética , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/metabolismo , DNA Mitocondrial/metabolismo , Regulação Viral da Expressão Gênica , Interações entre Hospedeiro e Microrganismos , Humanos , Imunidade Inata , Mitocôndrias/imunologia , Mitocôndrias/metabolismo , Mitocôndrias/virologia , Pandemias , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/genética , Pneumonia Viral/imunologia , Pneumonia Viral/metabolismo , Replicação Viral
15.
Ann N Y Acad Sci ; 1475(1): 64-77, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32557680

RESUMO

Approximately 15% of pregnant women vape electronic cigarettes (e-cigarettes), exposing the fetus to a range of toxic compounds, including nicotine and by-products of e-cigarette liquid (e-liquid) pyrolysis. Owing to the recent emergence of these products, research mainly focuses on immediate users, and not on in utero exposure. Therefore, this study aimed to understand the impact of intrauterine e-cigarette vapor (e-vapor) exposure, with and without nicotine, on liver metabolic markers in the male offspring. E-vapor was generated using an e-cigarette filled with tobacco-flavored e-liquid (18 or 0 mg/mL nicotine). Female Balb/c mice were exposed to e-vapor for 6 weeks before mating, through gestation and lactation, without direct exposure to the offspring. Livers and plasma from dams and male offspring (13 weeks old) were examined. Exposure to nicotine-free e-vapor promoted metabolic changes and liver damage in both the dams and their offspring. Furthermore, exposure to nicotine-containing e-vapor did not cause liver damage but induced hepatic steatosis in the adult offspring. Therefore, maternal vaping is detrimental to both the dams and their offspring, with nicotine providing a potential protective effect.


Assuntos
Sistemas Eletrônicos de Liberação de Nicotina , Fígado/patologia , Nutrientes/metabolismo , Animais , Antioxidantes/metabolismo , Área Sob a Curva , Autofagia , Biomarcadores/metabolismo , DNA Mitocondrial/metabolismo , Feminino , Regulação da Expressão Gênica , Fígado/metabolismo , Masculino , Camundongos Endogâmicos BALB C , Mitocôndrias Hepáticas/metabolismo , Mitofagia , Estresse Oxidativo , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
16.
Proc Natl Acad Sci U S A ; 117(25): 14306-14313, 2020 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-32513727

RESUMO

Ribonucleotides (rNMPs) incorporated in the nuclear genome are a well-established threat to genome stability and can result in DNA strand breaks when not removed in a timely manner. However, the presence of a certain level of rNMPs is tolerated in mitochondrial DNA (mtDNA) although aberrant mtDNA rNMP content has been identified in disease models. We investigated the effect of incorporated rNMPs on mtDNA stability over the mouse life span and found that the mtDNA rNMP content increased during early life. The rNMP content of mtDNA varied greatly across different tissues and was defined by the rNTP/dNTP ratio of the tissue. Accordingly, mtDNA rNMPs were nearly absent in SAMHD1 -/- mice that have increased dNTP pools. The near absence of rNMPs did not, however, appreciably affect mtDNA copy number or the levels of mtDNA molecules with deletions or strand breaks in aged animals near the end of their life span. The physiological rNMP load therefore does not contribute to the progressive loss of mtDNA quality that occurs as mice age.


Assuntos
DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Instabilidade Genômica/fisiologia , Ribonucleotídeos/genética , Ribonucleotídeos/metabolismo , Animais , Dano ao DNA , Feminino , Dosagem de Genes , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Nucleotídeos , Proteína 1 com Domínio SAM e Domínio HD/genética
18.
Mutat Res ; 783: 108298, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32386748

RESUMO

This short review explores the utility and applications of CRISPR/Cas9 systems in radiobiology. Specifically, in the context of experimentally simulating genotoxic effects of Ionizing Radiation (IR) to determine the contributions from DNA targets and 'Complex Double-Stranded Breaks' (complex DSBs) to the IR response. To elucidate this objective, this review considers applications of CRISPR/Cas9 on nuclear DNA targets to recognize the respective 'nucleocentric' response. The article also highlights contributions from mitochondrial DNA (mtDNA) - an often under-recognized target in radiobiology. This objective requires accurate experimental simulation of IR-like effects and parameters with the CRISPR/Cas9 systems. Therefore, the role of anti-CRISPR proteins in modulating enzyme activity to simulate dose rate - an important factor in radiobiology experiments is an important topic of this review. The applications of auxiliary domains on the Cas9 nuclease to simulate oxidative base damage and multiple stressor experiments are also topics of discussion. Ultimately, incorporation of CRISPR/Cas9 experiments into computational parameters in radiobiology models of IR damage and shortcomings to the technology are discussed as well. Altogether, the simulation of IR parameters and lack of damage to non-DNA targets in the CRISPR/Cas9 system lends this rapidly emerging tool as an effective model of IR induced DNA damage. Therefore, this literature review ultimately considers the relevance of complex DSBs to radiobiology with respect to using the CRISPR/Cas9 system as an effective experimental tool in models of IR induced effects.


Assuntos
Sistemas CRISPR-Cas , Quebras de DNA de Cadeia Dupla , DNA/efeitos da radiação , Modelos Genéticos , Testes de Mutagenicidade/métodos , Proteína 9 Associada à CRISPR , DNA/metabolismo , Dano ao DNA , Reparo do DNA , DNA Mitocondrial/metabolismo , DNA Mitocondrial/efeitos da radiação , Humanos , Radiação Ionizante
19.
Orv Hetil ; 161(20): 821-828, 2020 05 01.
Artigo em Húngaro | MEDLINE | ID: mdl-32364361

RESUMO

The protein product of the nuclear-encoded POLG gene plays a key role in the maintenance of mitochondrial DNA replication, and its failure causes multi-system diseases with varying severity. The clinical spectrum is extremely wide, and the most common symptoms include ptosis, myoclonus, epilepsy, myopathy, sensory ataxia, parkinsonism, cognitive decline and infertility. Now, it is known that mitochondrial dysfunction in Parkinson's disease plays a key role in the loss of dopaminergic neurons in the substantia nigra. Therefore, changes in the POLG gene may influence the development of various hereditary neurodegenerative diseases, including monogenic parkinsonism. However, only limited information is available on the relationship between Parkinson's disease and POLG gene and until now, there are no available data about the Hungarian population. In our study, we performed a next-generation sequencing study of 67 Hungarian patients with parkinsonism and analyzed the potentially damaging alterations in the POLG gene. 3 patients have been identified with a potential pathogen variant. In this study, we would like to call attention to the fact that during the differential diagnosis of parkinsonism, the possible involvement of POLG gene should be kept in mind. Especially in the presence of additional symptoms, such as ophthalmoparesis, non-vascular white matter lesions, psychiatric comorbidity, and relatively early age of onset, the POLG gene should be taken into consideration. Based on previous data from the literature and our own experience, we have summarized a possible diagnostic approach for POLG-associated parkinsonism. Orv Hetil. 2020; 161(20): 821-828.


Assuntos
Polimerase do DNA Mitocondrial/genética , Predisposição Genética para Doença , Doença de Parkinson/genética , Comorbidade , DNA Mitocondrial/metabolismo , Humanos , Hungria , Transtornos Mentais/genética , Mutação , Oftalmoplegia/genética , Doença de Parkinson/diagnóstico , Transtornos Parkinsonianos/genética
20.
Life Sci ; 255: 117758, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32407845

RESUMO

AIMS: NLR family pyrin domain containing 3 (NLRP3) inflammasome activation contributes to the development of diabetic cardiovascular complications. CD38 regulates vascular inflammation through cyclic ADP-ribose (cADPR)-mediated Ca2+ signaling in vascular smooth muscle cells (VSMCs). Ca2+ mobilization may modulate inflammasome activation by impacting mitochondrial function. However, it remains unclear whether CD38 regulates NLRP3 inflammasome activation in VSMCs through cADPR-dependent Ca2+ release under diabetic condition. Main methods and key findings: In VSMCs, we observed that high glucose (HG, 30 mM) enhanced CD38 protein expression and ADP ribosyl cyclase activity. Moreover, along with less abundance of NLRP3, apoptosis-associated speck-like protein containing CARD (ASC) and their colocalization, the expression of active caspase-1(p20) and IL-1ß were significantly inhibited by CD38 gene deficiency with siRNA transfection in VSMCs. Further, CD38 regulated the release of intracellular cADPR-mediated Ca2+ and mitochondrial DNA (mtDNA) to the cytosol, which was associated with NLRP3 inflammasome activation and VSMCs proliferation and collagen I synthesis. Finally, we found that CD38 inhibitors, nicotinamide and telmisartan significantly improved the endothelium-independent contraction and vascular remodeling, which was also associated with the inhibition of NLRP3 inflammasome in the aorta media in the diabetic mice. SIGNIFICANCE: Our data suggested that CD38/cADPR-mediated Ca2+ signaling contributed to the mitochondrial damage, consequently released mtDNA to the cytosol, which was related with NLRP3 inflammasome activation and VSMCs remodeling in diabetic mice.


Assuntos
ADP-Ribosil Ciclase 1/metabolismo , Cálcio/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Inflamassomos/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Sinalização do Cálcio/fisiologia , ADP-Ribose Cíclica/metabolismo , DNA Mitocondrial/metabolismo , Diabetes Mellitus Experimental/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/patologia , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia
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