RESUMEN
The mitochondrial permeability transition (MPT) pore regulates necrotic cell death following diverse cardiac insults. While the componentry of the pore itself remains controversial, Cyclophilin D (CypD) has been well-established as a positive regulator of pore opening. We have previously identified Complement 1q-binding protein (C1qbp) as a novel CypD-interacting molecule and a negative regulator of MPT-dependent cell death in vitro. However, its effects on the MPT pore and sensitivity to cell death in the heart remain untested. We therefore hypothesized that C1qbp would inhibit MPT in cardiac mitochondria and protect cardiac myocytes against cell death in vivo. To investigate the effects of C1qbp in the myocardium we generated gain- and loss-of-function mice. Transgenic C1qbp overexpression resulted in decreased complex protein expression and reduced mitochondrial respiration and ATP production but MPT was unaffected. In contrast, while C1qbp+/- mice did not exhibit any changes in mitochondrial protein expression, respiration, or ATP, the MPT pore was markedly sensitized to Ca2+ in these animals. Neither overexpression nor depletion of C1qbp significantly affected baseline heart morphology or function at 3 months of age. When subjected to myocardial infarction, C1qbp transgenic mice exhibited similar infarct sizes and cardiac remodeling to non-transgenic mice, consistent with the lack of an effect on MPT. In contrast, cardiac scar formation and dysfunction were significantly increased in the C1qbp+/- mice compared to C1qbp+/+ controls. Our results suggest that C1qbp is required for normal regulation of the MPT pore and mitochondrial function, and influences cardiac remodeling following MI, the latter more likely being independent of C1qbp effects on the MPT pore.
Asunto(s)
Ratones Transgénicos , Poro de Transición de la Permeabilidad Mitocondrial , Infarto del Miocardio , Miocitos Cardíacos , Animales , Infarto del Miocardio/metabolismo , Infarto del Miocardio/patología , Poro de Transición de la Permeabilidad Mitocondrial/metabolismo , Ratones , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Remodelación Ventricular , Mitocondrias Cardíacas/metabolismo , Calcio/metabolismo , Peptidil-Prolil Isomerasa F/metabolismo , Peptidil-Prolil Isomerasa F/genética , Proteínas de Transporte de Membrana Mitocondrial/metabolismo , Proteínas de Transporte de Membrana Mitocondrial/genética , Necrosis por Permeabilidad de la Transmembrana Mitocondrial , Proteínas Portadoras/metabolismo , Proteínas Portadoras/genética , Adenosina Trifosfato/metabolismo , Proteínas MitocondrialesRESUMEN
OBJECTIVE: The aim of this study was to evaluate mitofusin-2 levels and fetal Doppler ultrasonography effects in patients with severe preeclampsia. METHODS: This single-center case-control study was conducted in the gynecology service of the university hospital in Van. A total of 90 pregnant women aged 18-40 years were included in the study. Of these, 30 are normal, 30 have mild preeclampsia, and 30 are pregnant with severe preeclampsia. In this study, especially in severe preeclampsia patients, serum mitofusin-2 levels and important fetal Doppler flows such as uterine arterial pressure, umbilical arterial pressure, and 1st and 5th minute Apgar scores, birth weight, and the relationship between postnatal outcomes such as week of birth and the number of patients in the neonatal intensive care unit were investigated. RESULTS: There was a significant difference between the three groups in terms of mitofusin-2 levels, which was the highest in the group (p<0.05). Maternal serum mitofusin-2 levels were positively correlated with uterine arterial pressure (r=0.543, p=0.007), umbilical arterial pressure (r=0.238, p=0.008), diastolic blood pressure, and systolic blood pressure (p<0.001). Receiver operating characteristic curve of mitofusin-2 in predicting preeclampsia is as follows: optimal cutoff 1.6 ng/mL; area under the curve: 0.861; 95%CI: 0.786-0.917; sensitivity: 83.9%; and specificity: 70.0%, (p≤0.001). A one-unit increase in mitofusin-2 resulted in a statistically significant 4.21-fold increase in preeclampsia risk. CONCLUSION: This study recommends the use of mitofusin-2 together with fetal Doppler ultrasound findings as a reliable indicator of preeclampsia severity.
Asunto(s)
Preeclampsia , Resultado del Embarazo , Índice de Severidad de la Enfermedad , Ultrasonografía Prenatal , Humanos , Femenino , Embarazo , Preeclampsia/sangre , Preeclampsia/diagnóstico por imagen , Adulto , Estudios de Casos y Controles , Adulto Joven , Adolescente , GTP Fosfohidrolasas/sangre , Proteínas Mitocondriales/sangre , Biomarcadores/sangre , Valor Predictivo de las Pruebas , Puntaje de Apgar , Ultrasonografía Doppler , Curva ROC , Arterias Umbilicales/diagnóstico por imagenRESUMEN
BACKGROUND: Adipose and muscle tissue wasting outlines the cachectic process during tumor progression. The sympathetic nervous system (SNS) is known to promote tumor progression and research suggests that it might also contribute to cancer-associated cachexia (CAC) energetic expenditure through fat wasting. METHODS: We sympathectomized L5178Y-R tumor-bearing male BALB/c mice by intraperitoneally administering 6-hydroxydopamine to evaluate morphometric, inflammatory, and molecular indicators of CAC and tumor progression. RESULTS: Tumor burden was associated with cachexia indicators, including a 10.5% body mass index (BMI) decrease, 40.19% interscapular, 54% inguinal, and 37.17% visceral adipose tissue loss, a 12% food intake decrease, and significant (p = 0.038 and p = 0.0037) increases in the plasmatic inflammatory cytokines IL-6 and IFN-γ respectively. Sympathectomy of tumor-bearing mice was associated with attenuated BMI and visceral adipose tissue loss, decreased interscapular Ucp-1 gene expression to basal levels, and 2.6-fold reduction in Mmp-9 relative gene expression, as compared with the unsympathectomized mice control group. CONCLUSION: The SNS contributes to CAC-associated morphometric and adipose tissue alterations and promotes tumor progression in a murine model.
Asunto(s)
Caquexia , Progresión de la Enfermedad , Ratones Endogámicos BALB C , Sistema Nervioso Simpático , Animales , Caquexia/metabolismo , Caquexia/patología , Caquexia/etiología , Sistema Nervioso Simpático/metabolismo , Sistema Nervioso Simpático/fisiopatología , Masculino , Ratones , Proteína Desacopladora 1/metabolismo , Línea Celular Tumoral , Canales Iónicos/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Oxidopamina , Simpatectomía Química , Interleucina-6/metabolismo , Índice de Masa Corporal , Neoplasias/complicaciones , Neoplasias/patología , Neoplasias/metabolismoRESUMEN
Mitofusins (Mfn1 and Mfn2) are the mitochondrial outer-membrane fusion proteins in mammals and belong to the dynamin superfamily of multidomain GTPases. Recent structural studies of truncated variants lacking alpha helical transmembrane domains suggested that Mfns dimerize to promote the approximation and the fusion of the mitochondrial outer membranes upon the hydrolysis of guanine 5'-triphosphate disodium salt (GTP). However, next to the presence of GTP, the fusion activity seems to require multiple regulatory factors that control the dynamics and kinetics of mitochondrial fusion through the formation of Mfn1-Mfn2 heterodimers. Here, we purified and reconstituted the full-length murine Mfn2 protein into giant unilamellar vesicles (GUVs) with different lipid compositions. The incubation with GTP resulted in the fusion of Mfn2-GUVs. High-speed video-microscopy showed that the Mfn2-dependent membrane fusion pathway progressed through a zipper mechanism where the formation and growth of an adhesion patch eventually led to the formation of a membrane opening at the rim of the septum. The presence of physiological concentration (up to 30 mol%) of dioleoyl-phosphatidylethanolamine (DOPE) was shown to be a requisite to observe GTP-induced Mfn2-dependent fusion. Our observations show that Mfn2 alone can promote the fusion of micron-sized DOPE-enriched vesicles without the requirement of regulatory cofactors, such as membrane curvature, or the assistance of other proteins.
Asunto(s)
GTP Fosfohidrolasas , Fusión de Membrana , Animales , GTP Fosfohidrolasas/metabolismo , GTP Fosfohidrolasas/genética , Ratones , Fusión de Membrana/fisiología , Liposomas Unilamelares/metabolismo , Liposomas Unilamelares/química , Guanosina Trifosfato/metabolismo , Fosfatidiletanolaminas/metabolismo , Membranas Mitocondriales/metabolismo , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Mitocondrias/metabolismoRESUMEN
Methylphenidate (MPH) is a central nervous system stimulant drug and a first order prescription in the treatment of Attention Deficit Hyperactivity Disorder (ADHD). Although MPH biochemistry in neurodevelopment is not completely understood, studies showed it alters energy metabolism in rat brains. ADHD prevalence during neurodevelopment is related to males and the investigation has been mainly done in these subjects, therefore, little is known about MPH action in females and, consequently, about sexual dimorphism. In the present study we evaluated markers of mitochondrial dynamics (DRP1 and MFN2, fission and fusion, respectively), biogenesis (mtTFA) and bioenergetics (respiratory chain complexes) in prefrontal cortex of male and female juvenile rats submitted to exposure to MPH to better understand MPH effect during postnatal neurodevelopment. ATP and oxidative stress levels were also evaluated. Wistar rats received intraperitoneal injection of MPH (2.0 mg/kg) or control (saline), once a day, from 15th to 45th day of age. Results showed that MPH increased DRP1 and decreased MFN2, as well as increased mtTFA in prefrontal cortex of male rats. In female, MPH decreased NRF1 and increased Parkin, which are mitochondrial regulatory proteins. Respiratory chain complexes (complex I, SDH, complexes III and IV), ATP production and oxidative stress parameters were altered and shown to be sex-dependent. Taken together, results suggest that chronic MPH exposure at an early age in healthy animals changes mitochondrial dynamics, biogenesis and bioenergetics differently depending on the sex of the subjects.
Asunto(s)
Estimulantes del Sistema Nervioso Central , Dinaminas , Metabolismo Energético , Metilfenidato , Dinámicas Mitocondriales , Estrés Oxidativo , Corteza Prefrontal , Ratas Wistar , Animales , Corteza Prefrontal/efectos de los fármacos , Corteza Prefrontal/metabolismo , Metilfenidato/farmacología , Masculino , Dinámicas Mitocondriales/efectos de los fármacos , Femenino , Estimulantes del Sistema Nervioso Central/farmacología , Metabolismo Energético/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Dinaminas/metabolismo , Ratas , Caracteres Sexuales , Adenosina Trifosfato/metabolismo , GTP Fosfohidrolasas/metabolismo , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas Mitocondriales , Ubiquitina-Proteína LigasasRESUMEN
ABSTRACT: Mitochondrial dysfunction is a recognized feature of sepsis, characterized by ultrastructural damage, diminished oxidative phosphorylation, and depletion of mitochondrial antioxidant capacity observed in deceased septic patients. LPS tolerance induces a controlled response to sepsis. This study aimed to evaluate the function of tolerant mitochondria after cecal ligation and puncture (CLP)-induced sepsis. Mytochondrial oxygen consumption was determined using polarography. Extraction and quantification of RNA for the expression of Tfam, Nrf-1, and Ppargc-1α, and respiratory complex activity were measured. CLP-tolerant animals presented preserved respiratory rates of S3 and S4 and a ratio of respiratory control (RCR) compared to CLP-nontolerant animals with reduced oxidative phosphorylation and increased uncoupled respiration. Complex I Vmax was reduced in septic animals; however, CLP animals sustained normal Vmax. Mitochondrial biogenesis was preserved in CLP-tolerant animals compared to the CLP-nontolerant group, likely due to increased TFAM expression. LPS tolerance protected septic animals from mitochondrial dysfunction, favoring mitochondrial biogenesis and preserving mitochondrial respiration and respiratory complex I activity.
Asunto(s)
Lipopolisacáridos , Mitocondrias , Choque Séptico , Animales , Lipopolisacáridos/farmacología , Masculino , Mitocondrias/metabolismo , Ratas , Choque Séptico/metabolismo , Biogénesis de Organelos , Consumo de Oxígeno , Ratas Wistar , Factores de Transcripción/metabolismo , Proteínas Mitocondriales/metabolismo , Respiración de la Célula/efectos de los fármacos , Respiración de la Célula/fisiología , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Proteínas de Unión al ADN/metabolismo , Fosforilación Oxidativa/efectos de los fármacosRESUMEN
Overall health relies on features of skeletal muscle that generally decline with age, partly due to mechanisms associated with mitochondrial redox imbalance and bioenergetic dysfunction. Previously, aged mice genetically devoid of the mitochondrial NAD(P)+ transhydrogenase (NNT, encoded by the nicotinamide nucleotide transhydrogenase gene), an enzyme involved in mitochondrial NADPH supply, were shown to exhibit deficits in locomotor behavior. Here, by using young, middle-aged, and older NNT-deficient (Nnt-/-) mice and age-matched controls (Nnt+/+), we aimed to investigate how muscle bioenergetic function and motor performance are affected by NNT expression and aging. Mice were subjected to the wire-hang test to assess locomotor performance, while mitochondrial bioenergetics was evaluated in fiber bundles from the soleus, vastus lateralis and plantaris muscles. An age-related decrease in the average wire-hang score was observed in middle-aged and older Nnt-/- mice compared to age-matched controls. Although respiratory rates in the soleus, vastus lateralis and plantaris muscles did not significantly differ between the genotypes in young mice, the rates of oxygen consumption did decrease in the soleus and vastus lateralis muscles of middle-aged and older Nnt-/- mice. Notably, the soleus, which exhibited the highest NNT expression level, was the muscle most affected by aging, and NNT loss. Additionally, histology of the soleus fibers revealed increased numbers of centralized nuclei in older Nnt-/- mice, indicating abnormal morphology. In summary, our findings suggest that NNT expression deficiency causes locomotor impairments and muscle dysfunction during aging in mice.
Asunto(s)
Envejecimiento , Metabolismo Energético , Mitocondrias Musculares , Músculo Esquelético , Animales , Envejecimiento/metabolismo , Envejecimiento/fisiología , Ratones , Músculo Esquelético/metabolismo , Mitocondrias Musculares/metabolismo , Masculino , NADP Transhidrogenasa AB-Específica/metabolismo , NADP Transhidrogenasa AB-Específica/genética , Consumo de Oxígeno/fisiología , Ratones Noqueados , Ratones Endogámicos C57BL , Proteínas MitocondrialesRESUMEN
OBJECTIVES: This study explored novel biomarkers that can affect the diagnosis and treatment in Alzheimer's Disease (AD) related to mitochondrial metabolism. METHODS: The authors obtained the brain tissue datasets for AD from the Gene Expression Omnibus (GEO) and downloaded the mitochondrial metabolism-related genes set from MitoCarta 3.0 for analysis. Differentially Expressed Genes (DEGs) were screened using the "limma" R package, and the biological functions and pathways were investigated by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. The LASSO algorithm was used to identify the candidate center genes and validated in the GSE97760 dataset. PMAIP1 with the highest diagnostic value was selected and its effect on the occurrence of AD by biological experiments. RESULTS: A sum of 364 DEGs and 50 hub genes were ascertained. GO and KEGG enrichment analysis demonstrated that DEGs were preponderantly associated with cell metabolism and apoptosis. Five genes most associated with AD as candidate central genes by LASSO algorithm analysis. Then, the expression level and specificity of candidate central genes were verified by GSE97760 dataset, which confirmed that PMAIP1 had a high diagnostic value. Finally, the regulatory effects of PMAIP1 on apoptosis and mitochondrial function were detected by siRNA, flow cytometry and Western blot. siRNA-PMAIP1 can alleviate mitochondrial dysfunction and inhibit cell apoptosis. CONCLUSION: This study identified biomarkers related to mitochondrial metabolism in AD and provided a theoretical basis for the diagnosis of AD. PMAIP1 was a potential candidate gene that may affect mitochondrial function in Hippocampal neuronal cells, and its mechanism deserves further study.
Asunto(s)
Enfermedad de Alzheimer , Biología Computacional , Humanos , Algoritmos , Enfermedad de Alzheimer/genética , Apoptosis/genética , Biomarcadores/análisis , Biomarcadores/metabolismo , Perfilación de la Expresión Génica/métodos , Ontología de Genes , Genes Mitocondriales/genética , Mitocondrias/genética , Mitocondrias/metabolismo , Proteínas Mitocondriales/genéticaRESUMEN
The respiratory chain alternative enzymes (AEs) NDX and AOX from the tunicate Ciona intestinalis (Ascidiacea) have been xenotopically expressed and characterized in human cells in culture and in the model organisms Drosophila melanogaster and mouse, with the purpose of developing bypass therapies to combat mitochondrial diseases in human patients with defective complexes I and III/IV, respectively. The fact that the genes coding for NDX and AOX have been lost from genomes of evolutionarily successful animal groups, such as vertebrates and insects, led us to investigate if the composition of the respiratory chain of Ciona and other tunicates differs significantly from that of humans and Drosophila, to accommodate the natural presence of AEs. We have failed to identify in tunicate genomes fifteen orthologous genes that code for subunits of the respiratory chain complexes; all of these putatively missing subunits are peripheral to complexes I, III and IV in mammals, and many are important for complex-complex interaction in supercomplexes (SCs), such as NDUFA11, UQCR11 and COX7A. Modeling of all respiratory chain subunit polypeptides of Ciona indicates significant structural divergence that is consistent with the lack of these fifteen clear orthologous subunits. We also provide evidence using Ciona AOX expressed in Drosophila that this AE cannot access the coenzyme Q pool reduced by complex I, but it is readily available to oxidize coenzyme Q molecules reduced by glycerophosphate oxidase, a mitochondrial inner membrane-bound dehydrogenase that is not involved in SCs. Altogether, our results suggest that Ciona AEs might have evolved in a mitochondrial inner membrane environment much different from that of mammals and insects, possibly without SCs; this correlates with the preferential functional interaction between these AEs and non-SC dehydrogenases in heterologous mammalian and insect systems. We discuss the implications of these findings for the applicability of Ciona AEs in human bypass therapies and for our understanding of the evolution of animal respiratory chain.
Asunto(s)
Ciona intestinalis , Proteínas Mitocondriales , Fosforilación Oxidativa , Animales , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Ciona intestinalis/genética , Ciona intestinalis/enzimología , Humanos , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Subunidades de Proteína/metabolismo , Subunidades de Proteína/genética , Drosophila melanogaster/genética , Drosophila melanogaster/enzimología , Urocordados/genética , Urocordados/enzimología , Transporte de Electrón , Complejo I de Transporte de Electrón/metabolismo , Complejo I de Transporte de Electrón/genética , Filogenia , Proteínas de PlantasRESUMEN
To assess and validate the gene expression profile of SIRTs (SIRT1, SIRT2, SIRT3, SIRT4, SIRT5, SIRT6, and SIRT7) in relation to the pathogenesis and prognostic progression of Myelodysplastic neoplasm (MDS). Eighty bone marrow samples of patients with de novo MDS were diagnosed according to WHO 2022 and IPSS-R criteria. Ten bone marrow samples were obtained from elderly healthy volunteers and used as control samples. Gene expression levels of all SIRTs were assessed using RT-qPCR assays. Downregulation of SIRT2 (p = 0.009), SIRT3 (p = 0.048), SIRT4 (p = 0.049), SIRT5 (p = 0.046), SIRT6 (p = 0.043), and SIRT7 (p = 0.047) was identified in MDS patients compared to control individuals. Also, we identified that while SIRT2-7 genes are typically down-regulated in MDS patients compared to normal controls, there are relative expression variations among MDS patient subgroups. Specifically, SIRT4 (p = 0.029) showed increased expression in patients aged 60 or above, and both SIRT2 (p = 0.016) and SIRT3 (p = 0.036) were upregulated in patients with hemoglobin levels below 8 g/dL. SIRT2 (p = 0.045) and SIRT3 (p = 0.033) were highly expressed in patients with chromosomal abnormalities. Different SIRTs exhibited altered expression patterns concerning specific MDS clinical and prognostic characteristics. The downregulation in SIRTs genes (e.g., SIRT2 to SIRT7) expression in Brazilian MDS patients highlights their role in the disease's development. The upregulation of SIRT2 and SIRT3 in severe anemia patients suggests a potential link to manage iron overload-related complications in transfusion-dependent patients. Moreover, the association of SIRT2/SIRT3 with genomic instability and their role in MDS progression signify promising areas for future research and therapeutic targets. These findings underscore the importance of SIRT family in understanding and addressing MDS, offering novel clinical, prognostic, and therapeutic insights for patients with this condition.
Asunto(s)
Proteínas Mitocondriales , Síndromes Mielodisplásicos , Sirtuina 3 , Sirtuinas , Humanos , Sirtuinas/genética , Sirtuinas/metabolismo , Masculino , Femenino , Anciano , Persona de Mediana Edad , Síndromes Mielodisplásicos/genética , Pronóstico , Sirtuina 3/genética , Sirtuina 3/metabolismo , Sirtuina 2/genética , Sirtuina 2/metabolismo , Adulto , Anciano de 80 o más Años , Sirtuina 1/genética , Sirtuina 1/metabolismo , Regulación Neoplásica de la Expresión Génica , Perfilación de la Expresión Génica/métodos , Estudios de Casos y ControlesRESUMEN
The protein p32 (C1QBP) is a multifunctional and multicompartmental homotrimer that is overexpressed in many cancer types, including colon cancer. High expression levels of C1QBP are negatively correlated with the survival of patients. Previously, we demonstrated that C1QBP is an essential promoter of migration, chemoresistance, clonogenic, and tumorigenic capacity in colon cancer cells. However, the mechanisms underlying these functions and the effects of specific C1QBP protein inhibitors remain unexplored. Here, we show that the specific pharmacological inhibition of C1QBP with the small molecule M36 significantly decreased the viability rate, clonogenic capacity, and proliferation rate of different colon cancer cell lines in a dose-dependent manner. The effects of the inhibitor of C1QBP were cytostatic and non-cytotoxic, inducing a decreased activation rate of critical pro-malignant and mitogenic cellular pathways such as Akt-mTOR and MAPK in RKO colon cancer cells. Additionally, treatment with M36 significantly affected the mitochondrial integrity and dynamics of malignant cells, indicating that p32/C1QBP plays an essential role in maintaining mitochondrial homeostasis. Altogether, our results reinforce that C1QBP is an important oncogene target and that M36 may be a promising therapeutic drug for the treatment of colon cancer.
Asunto(s)
Neoplasias del Colon , Citostáticos , Humanos , Citostáticos/farmacología , Mitógenos/farmacología , Transducción de Señal , Proteínas Mitocondriales/metabolismo , Proliferación Celular , Proteínas Portadoras/metabolismoRESUMEN
Glioblastoma, a type of cancer affecting the central nervous system, is characterized by its poor prognosis and the dynamic alteration of its metabolic phenotype to fuel development and progression. Critical to cellular metabolism, mitochondria play a pivotal role, where the acetylation of lysine residues on mitochondrial enzymes emerges as a crucial regulatory mechanism of protein function. This post-translational modification, which negatively impacts the mitochondrial proteome's functionality, is modulated by the enzyme sirtuin 3 (SIRT3). Aiming to elucidate the regulatory role of SIRT3 in mitochondrial metabolism within glioblastoma, we employed high-resolution mass spectrometry to analyze the proteome and acetylome of two glioblastoma cell lines, each exhibiting distinct metabolic behaviors, following the chemical inhibition of SIRT3. Our findings reveal that the protein synthesis machinery, regulated by lysine acetylation, significantly influences the metabolic phenotype of these cells. Moreover, we have shed light on potential novel SIRT3 targets, thereby unveiling new avenues for future investigations. This research highlights the critical function of SIRT3 in mitochondrial metabolism and its broader implications for cellular energetics. It also provides a comparative analysis of the proteome and acetylome across glioblastoma cell lines with opposing metabolic phenotypes.
Asunto(s)
Glioblastoma , Sirtuina 3 , Humanos , Sirtuina 3/metabolismo , Proteoma/metabolismo , Lisina/metabolismo , Glioblastoma/metabolismo , Mitocondrias/metabolismo , Procesamiento Proteico-Postraduccional , Fenotipo , Acetilación , Proteínas Mitocondriales/metabolismoRESUMEN
INTRODUCTION AND OBJECTIVES: Acute liver injury (ALI) is characterized by massive hepatocyte death with high mortality and poor prognosis. Hepatocyte pyroptosis plays a key role in the physiopathological processes of ALI, which can damage mitochondria and release NLRP3 inflammasome particles, causing systemic inflammatory responses. Z-DNA Binding Protein 1 (ZBP1) is a sensor that induces cell death. Here, we investigated whether ZBP1 participates in hepatocyte pyroptosis and explored the possible pathogenesis of ALI. MATERIALS AND METHODS: Hepatocyte pyrotosis was induced with lipopolysaccharide (LPS) and nigericin (Nig), and the expression of Zbp1 (ZBP1) was examined by western blot analysis and RT-qPCR. Further, we transfected AML-12 (LO2 and HepG2) cell lines with Zbp1 (ZBP1) siRNA. After ZBP1 was silenced, LDH release and flow cytometry were used to measure the cell death; Western blot analysis and RT-qPCR were used to detect the marker of NLRP3 inflammasome activation and pyroptosis. We also detected the expression of mitochondrial linear rupture marker phosphoglycerate mutase family member 5 (PGAM5) using western blot analysis and reactive oxygen species (ROS) using the DCFH-DA method. RESULTS: The expression of ZBP1 was up-regulated in LPS/Nig-induced hepatocytes. Si-Zbp1 (Si-ZBP1) inhibited NLRP3 inflammasome activation and pyroptosis in LPS/Nig-induced hepatocytes. Moreover, ZBP1 silencing inhibited the expression of PGAM5 by reducing ROS production. CONCLUSIONS: ZBP1 promotes hepatocellular pyroptosis by modulating mitochondrial damage, which facilitates the extracellular release of ROS.
Asunto(s)
Hepatocitos , Lipopolisacáridos , Proteína con Dominio Pirina 3 de la Familia NLR , Piroptosis , Especies Reactivas de Oxígeno , Animales , Humanos , Células Hep G2 , Hepatocitos/metabolismo , Hepatocitos/patología , Inflamasomas/metabolismo , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Nigericina/farmacología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Fosfoproteínas Fosfatasas , Especies Reactivas de Oxígeno/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Transducción de SeñalRESUMEN
Three genes encoding mitochondrial uncoupling proteins (UCPs) have been described in Arabidopsis thaliana (UCP1 to UCP3). In plants, UCPs may act as an uncoupler or as an aspartate/glutamate exchanger. For instance, much of the data regarding UCP functionality were obtained for the UCP1 and UCP2 isoforms compared with UCP3. Here, to get a better understanding about the concerted action of UCP1 and UCP3 in planta, we investigated the transcriptome and metabolome profiles of ucp1 ucp3 double mutant plants during the vegetative phase. For that, 21-day-old mutant plants, which displayed the most evident phenotypic alterations compared to wild type (WT) plants, were employed. The double knockdown of UCP1 and UCP3, isoforms unequivocally present inside the mitochondria, promoted important transcriptional reprogramming with alterations in the expression of genes related to mitochondrial and chloroplast function as well as those responsive to abiotic stress, suggesting disturbances throughout the cell. The observed transcriptional changes were well integrated with the metabolomic data of ucp1 ucp3 plants. Alterations in metabolites related to primary and secondary metabolism, particularly enriched in the Alanine, Aspartate and Glutamate metabolism, were detected. These findings extend our knowledge of the underlying roles played by UCP3 in concert with UCP1 at the whole plant level.
Asunto(s)
Arabidopsis , Tejido Adiposo Pardo/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Ácido Aspártico , Glutamatos/metabolismo , Canales Iónicos/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Isoformas de Proteínas/metabolismo , Proteína Desacopladora 1/metabolismo , Proteína Desacopladora 3/metabolismoRESUMEN
BACKGROUND: Pathogenic variants in the nicotinamide nucleotide transhydrogenase gene (NNT) are a rare cause of primary adrenal insufficiency (PAI), as well as functional impairment of the gonads. OBJECTIVE: Despite the description of different homozygous and compound heterozygous NNT variants in PAI patients, the extent to which the function and expression of the mature protein are compromised remains to be clarified. DESIGN: The activity and expression of mitochondrial NAD(P)+ transhydrogenase (NNT) were analyzed in blood samples obtained from patients diagnosed with PAI due to genetically confirmed variants of the NNT gene (n = 5), heterozygous carriers as their parents (n = 8), and healthy controls (n = 26). METHODS: NNT activity was assessed by a reverse reaction assay standardized for digitonin-permeabilized peripheral blood mononuclear cells (PBMCs). The enzymatic assay was validated in PBMC samples from a mouse model of NNT absence. Additionally, the PBMC samples were evaluated for NNT expression by western blotting and reverse transcription quantitative polymerase chain reaction and for mitochondrial oxygen consumption. RESULTS: NNT activity was undetectable (<4% of that of healthy controls) in PBMC samples from patients, independent of the pathogenic genetic variant. In patients' parents, NNT activity was approximately half that of the healthy controls. Mature NNT protein expression was lower in patients than in the control groups, while mRNA levels varied widely among genotypes. Moreover, pathogenic NNT variants did not impair mitochondrial bioenergetic function in PBMCs. CONCLUSIONS: The manifestation of PAI in NNT-mutated patients is associated with a complete lack of NNT activity. Evaluation of NNT activity can be useful to characterize disease-causing NNT variants.
Asunto(s)
Enfermedad de Addison , NADP Transhidrogenasas , Animales , Humanos , Ratones , Leucocitos Mononucleares/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , NAD , NADP Transhidrogenasa AB-Específica/genética , NADP Transhidrogenasa AB-Específica/metabolismo , NADP Transhidrogenasas/genética , NADP Transhidrogenasas/metabolismoRESUMEN
Developing new pesticides poses a significant challenge in designing next-generation natural insecticides that selectively target specific pharmacological sites while ensuring environmental friendliness. In this study, we aimed to address this challenge by formulating novel natural pesticides derived from secondary plant metabolites, which exhibited potent insecticide activity. Additionally, we tested their effect on mitochondrial enzyme activity and the proteomic profile of Ae. aegypti, a mosquito species responsible for transmitting diseases. Initially, 110 key compounds from essential oils were selected that have been reported with insecticidal properties; then, to ensure safety for mammals were performed in silico analyses for toxicity properties, identifying non-toxic candidates for further investigation. Subsequently, in vivo tests were conducted using these non-toxic compounds, focusing on the mosquito's larval stage. Based on the lethal concentration (LC), the most promising compounds as insecticidal were identified as S-limonene (LC50 = 6.4 ppm, LC95 = 17.2 ppm), R-limonene (LC50 = 9.86 ppm, LC95 = 27.7 ppm), citronellal (LC50 = 40.5 ppm, LC95 = 68.6 ppm), R-carvone (LC50 = 61.4 ppm, LC95 = 121 ppm), and S-carvone (LC50 = 62.5 ppm, LC95 = 114 ppm). Furthermore, we formulated a mixture of R-limonene, S-carvone, and citronellal with equal proportions of each compound based on their LC50. This mixture specifically targeted mitochondrial proteins and demonstrated a higher effect that showed by each compound separately, enhancing the insecticidal activity of each compound. Besides, the proteomic profile revealed the alteration in proteins involved in proliferation processes and detoxification mechanisms in Ae. aegypti. In summary, our study presents a formulation strategy for developing next-generation natural insecticides using secondary plant metabolites with the potential for reducing the adverse effects on humans and the development of chemical resistance in insects. Our findings also highlight the proteomic alteration induced by the formulated insecticide, showing insight into the mechanisms of action and potential targets for further exploration in vector control strategies.
Asunto(s)
Monoterpenos Acíclicos , Aedes , Aldehídos , Monoterpenos Ciclohexánicos , Insecticidas , Animales , Humanos , Insecticidas/farmacología , Insecticidas/química , Limoneno/farmacología , Proteínas Mitocondriales/farmacología , Proteómica , Mosquitos Vectores , Larva , Extractos Vegetales/farmacología , MamíferosRESUMEN
BACKGROUND: The harsh conditions of high-altitude environments are known to drive the evolution of physiological and morphological traits in endothermic animals. These conditions are expected to result in the adaptive evolution of protein coding genes encoded in mitochondrial genomes that are vital for the oxidative phosphorylation pathway. In this study, we formally tested for signatures of adaptive evolution on mitochondrial protein coding genes in Tapirus pinchaque and other odd-toed ungulates inhabiting high-elevation environments. RESULTS: The AT-rich mitochondrial genome of T. pinchaque is 16,750 bp long. A phylomitogenomic analysis supports the monophyly of the genus Tapirus and families in the Perissodactyla. The ratio of non-synonymous to synonymous substitutions demonstrated that all mitochondrial genes undergo purifying selection in T. pinchaque and other odd ungulates living at high elevations. Over this negative background selection, Branch Models suggested that cox3 and nad6 might be undergoing stronger purifying selection than other mitochondrial protein coding genes. Furthermore, Site Models suggested that one and four sites in nad2 and nad5, respectively, could be experiencing positive selection. However, these results were supported by Likelihood Ratio Tests but not Bayesian Empirical Bayes posterior probabilities. Additional analyses (in DataMonkey) indicated a relaxation of selection strength in nad6, evidence of episodic diversifying selection in cob, and revealed episodic positive/diversifying selection signatures for two sites in nad1, and one site each in nad2 and nad4. CONCLUSION: The mitochondrial genome of T. pinchaque is an important genomic resource for conservation of this species and this study contributes to the understanding of adaptive evolution of mitochondrial protein coding genes in odd-toed ungulates inhabiting high-altitude environments.
Asunto(s)
Altitud , Genoma Mitocondrial , Animales , Teorema de Bayes , Perisodáctilos/genética , Proteínas MitocondrialesRESUMEN
Mitochondria are organelles present in the cytoplasm of eukaryotic cells; they play a key role in adenosine triphosphate (ATP) synthesis and oxidative phosphorylation. Mitochondria have their own DNA, mitochondrial DNA (mtDNA), keeping the function of the mitochondria. Mitochondrial transcription factor A (TFAM) is a member of the HMGB subfamily that binds to mtDNA promoters is and considered essential in mtDNA replication and transcription. More recently, TFAM has been shown to play a central role in the maintenance and regulation of mitochondrial copy number, inflammatory response, expression regulation, and mitochondrial genome activity. Gene editing tools such as the CRISPR-Cas 9 technique, TALENs, and other gene editing tools have been used to investigate the role of TFAM in mitochondrial mechanics and biogenesis as well as its correlation to mitochondrial disorders. Thus this chapter brings a summary of mitochondria function, dysfunction, the importance of TFAM in the maintenance of mitochondria, and state of the art of gene editing tools involving TFAM and mtDNA.
Asunto(s)
Edición Génica , Enfermedades Mitocondriales , Humanos , Dosificación de Gen , ADN Mitocondrial/genética , ADN Mitocondrial/metabolismo , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismo , Enfermedades Mitocondriales/genética , Enfermedades Mitocondriales/terapia , Enfermedades Mitocondriales/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
Mitochondrial translation is an intricate process involving both general and mRNA-specific factors. In addition, in the yeast Saccharomyces cerevisiae, translation of mitochondrial mRNAs is coupled to assembly of nascent polypeptides into the membrane. ARG8m is a reporter gene widely used to study the mechanisms of yeast mitochondrial translation. This reporter is a recodified gene that uses the mitochondrial genetic code and is inserted at the desired locus in the mitochondrial genome. After deletion of the endogenous nuclear gene, this reporter produces Arg8, an enzyme necessary for arginine biosynthesis. Since Arg8 is a soluble protein with no relation to oxidative phosphorylation, it is a reliable reporter to study mitochondrial mRNAs translation and dissect translation form assembly processes. In this chapter, we explain how to insert the ARG8m reporter in the desired spot in the mitochondrial DNA, how to analyze Arg8 synthesis inside mitochondria, and how to follow steady-state levels of the protein. We also explain how to use it to find spontaneous suppressors of translation defects.
Asunto(s)
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Biosíntesis de Proteínas , ADN Mitocondrial/genética , Mitocondrias/metabolismo , Proteínas Mitocondriales/genética , Proteínas Mitocondriales/metabolismoRESUMEN
Objective: Based on hypothetical hypothyroidism and nonthyroidal illness syndrome (NTIS) gene expression similarities, we decided to compare the patterns of expression of both as models of NTIS. The concordant profile between them may enlighten new biomarkers for NTIS challenging scenarios. Materials and methods: We used Ion Proton System next-generation sequencing to build the hypothyroidism transcriptome. We selected two databanks in GEO2 platform datasets to find the differentially expressed genes (DEGs) in adults and children with sepsis. The ROC curve was constructed to calculate the area under the curve (AUC). The AUC, chi-square, sensitivity, specificity, accuracy, kappa and likelihood were calculated. We performed Cox regression and Kaplan-Meier analyses for the survival analysis. Results: Concerning hypothyroidism DEGs, 70.42% were shared with sepsis survivors and 61.94% with sepsis nonsurvivors. Some of them were mitochondrial gene types (mitGenes), and 95 and 88 were related to sepsis survivors and nonsurvivors, respectively. BLOC1S1, ROMO1, SLIRP and TIMM8B mitGenes showed the capability to distinguish sepsis survivors and nonsurvivors. Conclusion: We matched our hypothyroidism DEGs with those in adults and children with sepsis. Additionally, we observed different patterns of hypothyroid-related genes among sepsis survivors and nonsurvivors. Finally, we demonstrated that ROMO1, SLIRP and TIMM8B could be predictive biomarkers in children´s sepsis.