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1.
Cell ; 148(4): 716-26, 2012 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-22341444

RESUMO

Mitochondrial dysfunction causes poorly understood tissue-specific pathology stemming from primary defects in respiration, coupled with altered reactive oxygen species (ROS), metabolic signaling, and apoptosis. The A1555G mtDNA mutation that causes maternally inherited deafness disrupts mitochondrial ribosome function, in part, via increased methylation of the mitochondrial 12S rRNA by the methyltransferase mtTFB1. In patient-derived A1555G cells, we show that 12S rRNA hypermethylation causes ROS-dependent activation of AMP kinase and the proapoptotic nuclear transcription factor E2F1. This retrograde mitochondrial-stress relay is operative in vivo, as transgenic-mtTFB1 mice exhibit enhanced 12S rRNA methylation in multiple tissues, increased E2F1 and apoptosis in the stria vascularis and spiral ganglion neurons of the inner ear, and progressive E2F1-dependent hearing loss. This mouse mitochondrial disease model provides a robust platform for deciphering the complex tissue specificity of human mitochondrial-based disorders, as well as the precise pathogenic mechanism of maternally inherited deafness and its exacerbation by environmental factors.


Assuntos
Surdez/metabolismo , Modelos Animais de Doenças , Fator de Transcrição E2F1/metabolismo , Animais , DNA Mitocondrial/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Orelha Interna/patologia , Cistos Glanglionares/patologia , Humanos , Camundongos , Camundongos Transgênicos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mutação , Neurônios/patologia , RNA Ribossômico/metabolismo , Espécies Reativas de Oxigênio , Transdução de Sinais , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
Trends Genet ; 39(2): 125-139, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36137834

RESUMO

Mitochondria, organelles that harbor their own circular genomes, are critical for energy production and homeostasis maintenance in eukaryotic cells. Recent studies discovered hundreds of mitochondria-encoded noncoding RNAs (mt-ncRNAs), including novel subtypes of mitochondria-encoded circular RNAs (mecciRNAs) and mitochondria-encoded double-stranded RNAs (mt-dsRNAs). Here, we discuss the emerging field of mt-ncRNAs by reviewing their expression patterns, biogenesis, metabolism, regulatory roles, and functional mechanisms. Many mt-ncRNAs have regulatory roles in cellular physiology, and some are associated with, or even act as, causal factors in human diseases. We also highlight developments in technologies and methodologies and further insights into future perspectives and challenges in studying these noncoding RNAs, as well as their potential biomedical applications.


Assuntos
RNA Longo não Codificante , RNA não Traduzido , Humanos , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , RNA Circular/genética , RNA Longo não Codificante/metabolismo
3.
Proc Natl Acad Sci U S A ; 120(8): e2218294120, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36787351

RESUMO

Chemical products, such as plastics, solvents, and fertilizers, are essential for supporting modern lifestyles. Yet, producing, using, and disposing of chemicals creates adverse environmental impacts which threaten the industry's license to operate. This study presents seven planet-compatible pathways toward 2050 employing demand-side and supply-side interventions with cumulative total investment costs of US$1.2-3.7 trillion. Resource efficiency and circularity interventions reduce global chemicals demand by 23 to 33% and are critical for mitigating risks associated with using fossil feedstocks and carbon capture and sequestration, and constraints on available biogenic and recyclate feedstocks. Replacing fossil feedstocks with biogenic/air-capture sources, shifting carbon destinations from the atmosphere to ground, and electrifying/decarbonizing energy supply for production technologies could enable net negative emissions of 0.5 GtCO2eq y-1 across non-ammonia chemicals, while still delivering essential chemical-based services to society.

4.
J Biol Chem ; 300(5): 107235, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38552739

RESUMO

Defects in mitochondrial RNA metabolism have been linked to sensorineural deafness that often occurs as a consequence of damaged or deficient inner ear hair cells. In this report, we investigated the molecular mechanism underlying a deafness-associated tRNAPhe 593T > C mutation that changed a highly conserved uracil to cytosine at position 17 of the DHU-loop. The m.593T > C mutation altered tRNAPhe structure and function, including increased melting temperature, resistance to S1 nuclease-mediated digestion, and conformational changes. The aberrant tRNA metabolism impaired mitochondrial translation, which was especially pronounced by decreases in levels of ND1, ND5, CYTB, CO1, and CO3 harboring higher numbers of phenylalanine. These alterations resulted in aberrant assembly, instability, and reduced activities of respiratory chain enzyme complexes I, III, IV, and intact supercomplexes overall. Furthermore, we found that the m.593T > C mutation caused markedly diminished membrane potential, and increased the production of reactive oxygen species in the mutant cell lines carrying the m.593T > C mutation. These mitochondrial dysfunctions led to the mitochondrial dynamic imbalance via increasing fission with abnormal mitochondrial morphology. Excessive fission impaired the process of autophagy including the initiation phase, formation, and maturation of the autophagosome. In particular, the m.593T > C mutation upregulated the PARKIN-dependent mitophagy pathway. These alterations promoted an intrinsic apoptotic process for the removal of damaged cells. Our findings provide critical insights into the pathophysiology of maternally inherited deafness arising from tRNA mutation-induced defects in mitochondrial and cellular integrity.


Assuntos
Surdez , Mitocôndrias , RNA de Transferência de Fenilalanina , Humanos , Autofagia , Surdez/genética , Surdez/metabolismo , Potencial da Membrana Mitocondrial , Mitocôndrias/metabolismo , Mitocôndrias/genética , Mitocôndrias/patologia , Dinâmica Mitocondrial , Mutação , Espécies Reativas de Oxigênio/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , RNA de Transferência de Fenilalanina/genética
5.
Hum Mol Genet ; 32(2): 231-243, 2023 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-35947995

RESUMO

Leber's hereditary optic neuropathy (LHON) is a maternally inherited eye disease that results from degeneration of retinal ganglion cells (RGC). Mitochondrial ND4 11778G > A mutation, which affects structural components of complex I, is the most prevalent LHON-associated mitochondrial DNA (mtDNA) mutation worldwide. The m.11778G > A mutation is the primary contributor underlying the development of LHON and X-linked PRICKLE3 allele (c.157C > T, p.Arg53Trp) linked to biogenesis of ATPase interacts with m.11778G > A mutation to cause LHON. However, the lack of appropriate cell and animal models of LHON has been significant obstacles for deep elucidation of disease pathophysiology, specifically the tissue-specific effects. Using RGC-like cells differentiated from induced pluripotent stem cells (iPSCs) from members of one Chinese family (asymptomatic subjects carrying only m.11778G > A mutation or PRICKLE3 p.Arg53Trp mutation, symptomatic individuals bearing both m.11778G > A and PRICKLE3 p.Arg53Trp mutations and control lacking these mutations), we demonstrated the deleterious effects of mitochondrial dysfunctions on the morphology and functions of RGCs. Notably, iPSCs bearing only m.11778G > A or p.Arg53Trp mutation exhibited mild defects in differentiation to RGC-like cells. The RGC-like cells carrying only m.11778G > A or p.Arg53Trp mutation displayed mild defects in RGC morphology, including the area of soma and numbers of neurites, electrophysiological properties, ATP contents and apoptosis. Strikingly, those RGC-like cells derived from symptomatic individuals harboring both m.11778G > A and p.Arg53Trp mutations displayed greater defects in the development, morphology and functions than those in cells bearing single mutation. These findings provide new insights into pathophysiology of LHON arising from RGC deficiencies caused by synergy between m.11778G > A and PRICKLE3 p.Arg53Trp mutation.


Assuntos
Células-Tronco Pluripotentes Induzidas , Atrofia Óptica Hereditária de Leber , Animais , Células Ganglionares da Retina , Atrofia Óptica Hereditária de Leber/genética , NADH Desidrogenase/genética , DNA Mitocondrial/genética , Mutação
6.
Hum Mol Genet ; 32(9): 1539-1551, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-36611011

RESUMO

Leber's hereditary optic neuropathy (LHON) is a maternally transmitted eye disease due to the degeneration of retinal ganglion cells (RGCs). Mitochondrial 11778G > A mutation is the most common LHON-associated mitochondrial DNA (mtDNA) mutation. Our recent studies demonstrated some LHON families manifested by synergic interaction between m.11778G > A mutation and YARS2 allele (c.572G > T, p.Gly191Val) encoding mitochondrial tyrosyl-tRNA synthetase. However, the RGC-specific effects of LHON-associated mtDNA mutations remain elusive and there is no highly effective therapy for LHON. Here, we generated patients-derived induced pluripotent stem cells (iPSCs) from fibroblasts derived from a Chinese LHON family (both m.11778G > A and c.572G > T mutations, only m.11778G > A mutation, and control subject). The c.572G > T mutation in iPSC lines from a syndromic individual was corrected by CRISPR/Cas9. Those iPSCs were differentiated into neural progenitor cells and subsequently induced RGC-like cells using a stepwise differentiation procedure. Those RGC-like cells derived from symptomatic individual harboring both m.11778G > A and c.572G > T mutations exhibited greater defects in neuronal differentiation, morphology including reduced area of soma, numbers of neurites and shortened length of axons, electrophysiological properties than those in cells bearing only m.11778G > A mutation. Furthermore, these RGC-like cells revealed more drastic reductions in oxygen consumption rates, levels of mitochondrial ATP and increasing productions of reactive oxygen species than those in other cell models. These mitochondrial dysfunctions promoted the apoptotic process for RGC degenerations. Correction of YARS2 c.572G > T mutation rescued deficiencies of patient-derived RGC-like cells. These findings provide new insights into pathophysiology of LHON arising from RGC-specific mitochondrial dysfunctions and step toward therapeutic intervention for this disease.


Assuntos
DNA Mitocondrial , Atrofia Óptica Hereditária de Leber , Células Ganglionares da Retina , Tirosina-tRNA Ligase , Humanos , Alelos , DNA Mitocondrial/genética , Células-Tronco Pluripotentes Induzidas/fisiologia , Células-Tronco Pluripotentes Induzidas/transplante , Mitocôndrias/genética , Mutação , Atrofia Óptica Hereditária de Leber/genética , Atrofia Óptica Hereditária de Leber/fisiopatologia , Atrofia Óptica Hereditária de Leber/terapia , Tirosina-tRNA Ligase/genética
7.
Hum Mol Genet ; 31(18): 3068-3082, 2022 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-35467742

RESUMO

Sensorineural hearing loss often results from damaged or deficient inner ear hair cells. Mitochondrial 12S rRNA 1555A>G mutation has been associated with hearing loss in many families. The m.1555A>G mutation is a primary factor underlying the development of hearing loss and TRMU allele (c.28G>T, p.Ala10Sser) encoding tRNA thiouridylase interact with m.1555A>G mutation to cause hearing loss. However, the tissue specificity of mitochondrial dysfunction remains elusive and there is no highly effective therapy for mitochondrial deafness. We report here the generation of induced pluripotent stem cells (iPSCs) from lymphoblastoid cell lines derived from members of an Arab-Israeli family (asymptomatic individual carrying only m.1555A>G mutation, symptomatic individual bearing both m.1555A>G and c.28G>T mutations, and control subject). The c.28G>T mutation in iPSC lines from a hearing-impaired subject was corrected by CRISPR/Cas9. These iPSCs were differentiated into otic epithelial progenitor (OEP) cells and subsequent inner ear hair cell (HC)-like cells. The iPSCs bearing m.1555A>G mutation exhibited mildly deficient differentiation into OEP and resultant HC-like cells displayed mild defects in morphology and electrophysiological properties. Strikingly, those HC-like cells harboring m.1555A>G and TRMU c.28G>T mutations displayed greater defects in the development, morphology and functions than those in cells bearing only m.1555A>G mutation. Transcriptome analysis of patients-derived HC-like cells revealed altered expressions of genes vital for mechanotransduction of hair cells. Genetic correction of TRMU c.28G>T mutation yielded morphologic and functional recovery of patient derived HC-like cells. These findings provide new insights into pathophysiology of maternally inherited hearing loss and a step toward therapeutic interventions for this disease.


Assuntos
Perda Auditiva , Células-Tronco Pluripotentes Induzidas , Alelos , DNA Mitocondrial/genética , Cabelo/metabolismo , Audição , Perda Auditiva/genética , Perda Auditiva/metabolismo , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Mecanotransdução Celular , Mitocôndrias/genética , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Mutação , RNA Ribossômico/genética , RNA de Transferência/metabolismo , tRNA Metiltransferases/genética
8.
Hum Mol Genet ; 31(19): 3299-3312, 2022 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-35567411

RESUMO

Leber's hereditary optic neuropathy (LHON) is a maternally inherited eye disease due to mitochondrial DNA (mtDNA) mutations. LHON-linked ND6 14484T > C (p.M64V) mutation affected structural components of complex I but its pathophysiology is poorly understood. The structural analysis of complex I revealed that the M64 forms a nonpolar interaction Y59 in the ND6, Y59 in the ND6 interacts with E34 of ND4L, and L60 of ND6 interacts with the Y114 of ND1. These suggested that the m.14484T > C mutation may perturb the structure and function of complex I. Mutant cybrids constructed by transferring mitochondria from lymphoblastoid cell lines of one Chinese LHON family into mtDNA-less (ρo) cells revealed decreases in the levels of ND6, ND1 and ND4L. The m.14484T > C mutation may affect mitochondrial mRNA homeostasis, supported by reduced levels of SLIRP and SUPV3L1 involved in mRNA degradation and increasing expression of ND6, ND1 and ND4L genes. These alterations yielded decreased activity of complex I, respiratory deficiency, diminished mitochondrial ATP production and reduced membrane potential, and increased production of reactive oxygen species in the mutant cybrids. Furthermore, the m.14484T > C mutation promoted apoptosis, evidenced by elevating Annexin V-positive cells, release of cytochrome c into cytosol, levels in apoptotic proteins BAX, caspases 3, 7, 9 and decreasing levels in anti-apoptotic protein Bcl-xL in the mutant cybrids. Moreover, the cybrids bearing the m.14484T > C mutation exhibited the reduced levels of autophagy protein LC3, increased levels of substrate P62 and impaired PINK1/Parkin-dependent mitophagy. Our findings highlighted the critical role of m.14484T > C mutation in the pathogenesis of LHON.


Assuntos
Atrofia Óptica Hereditária de Leber , Trifosfato de Adenosina , Anexina A5/genética , Apoptose/genética , Caspases , Citocromos c , DNA Mitocondrial/genética , Complexo I de Transporte de Elétrons/genética , Homeostase/genética , Humanos , Mitofagia/genética , Mutação , NADH Desidrogenase , Atrofia Óptica Hereditária de Leber/genética , Atrofia Óptica Hereditária de Leber/patologia , Proteínas Quinases/genética , RNA , RNA Mensageiro , RNA Mitocondrial , Proteínas de Ligação a RNA , Espécies Reativas de Oxigênio , Ubiquitina-Proteína Ligases/genética , Proteína X Associada a bcl-2/genética
9.
J Vasc Interv Radiol ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38723863

RESUMO

PURPOSE: To examine the relationship between hyperdense artery sign (HAS)/susceptibility vessel sign (SVS) and thrombus composition and evaluate the effect of HAS/SVS status on the association between first-line thrombectomy techniques and outcomes in patients with acute anterior circulation large vessel occlusion (LVO). MATERIALS AND METHODS: From January 2018 to June 2021, 103 consecutive patients with acute anterior circulation LVO (75 [63.1%] men; median age, 66 years) who underwent thrombectomy and for whom the removed clot was available for histological analyses were retrospectively reviewed. The presence of HAS and SVS was assessed on unenhanced computed tomography (CT) and susceptibility-weighted imaging, respectively. Association of first-line thrombectomy techniques (stent retriever [SR] combined with contact aspiration [CA] vs CA alone) with outcomes was assessed according to HAS/SVS status. RESULTS: Among the included patients, 55 (53.4%) were HAS/SVS-negative, and 69 (67.0%) underwent first-line SR + CA. Higher relative densities of fibrin/platelets (0.56 vs 0.51; P < .001) and lower relative densities of erythrocytes (0.32 vs 0.42; P < .001) were observed in HAS/SVS-negative patients compared with HAS/SVS-positive patients. First-line SR + CA was associated with reduced odds of distal embolization (adjusted odds ratio, 0.18; 95% CI, 0.04-0.83; P = .027) and a more favorable 90-day functional outcome (adjusted odds ratio, 5.29; 95% CI, 1.06-26.34; P = .042) in HAS/SVS-negative patients and a longer recanalization time (53 vs 25 minutes; P = .025) and higher risk of subarachnoid hemorrhage (24.2% vs 0%; P = .044) in HAS/SVS-positive patients. CONCLUSIONS: Absence of HAS/SVS may indicate a higher density of fibrin/platelets in the thrombus, and first-line SR + CA yielded superior functional outcomes than CA alone in patients with acute LVO without HAS/SVS.

10.
Nucleic Acids Res ; 50(16): 9453-9469, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36039763

RESUMO

In this report, we investigated the molecular mechanism underlying a deafness-associated m.5783C > T mutation that affects the canonical C50-G63 base-pairing of TΨC stem of tRNACys and immediately adjacent to 5' end of light-strand origin of mitochondrial DNA (mtDNA) replication (OriL). Two dimensional agarose gel electrophoresis revealed marked decreases in the replication intermediates including ascending arm of Y-fork arcs spanning OriL in the mutant cybrids bearing m.5783C > T mutation. mtDNA replication alterations were further evidenced by decreased levels of PolγA, Twinkle and SSBP1, newly synthesized mtDNA and mtDNA contents in the mutant cybrids. The m.5783C > T mutation altered tRNACys structure and function, including decreased melting temperature, conformational changes, instability and deficient aminoacylation of mutated tRNACys. The m.5783C > T mutation impaired the 5' end processing efficiency of tRNACys precursors and reduced the levels of tRNACys and downstream tRNATyr. The aberrant tRNA metabolism impaired mitochondrial translation, which was especially pronounced effects in the polypeptides harboring higher numbers of cysteine and tyrosine codons. These alterations led to deficient oxidative phosphorylation including instability and reduced activities of the respiratory chain enzyme complexes I, III, IV and intact supercomplexes overall. Our findings highlight the impact of mitochondrial dysfunction on deafness arising from defects in mitochondrial DNA replication and tRNA metabolism.


Assuntos
DNA Mitocondrial , Surdez , Humanos , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , RNA de Transferência de Cisteína/metabolismo , Surdez/genética , Surdez/metabolismo , Mitocôndrias/metabolismo , Mutação , Replicação do DNA/genética , Proteínas de Ligação a DNA/genética , Proteínas Mitocondriais/metabolismo
11.
Nucleic Acids Res ; 50(16): 9368-9381, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36018806

RESUMO

Pseudouridine (Ψ) at position 55 in tRNAs plays an important role in their structure and function. This modification is catalyzed by TruB/Pus4/Cbf5 family of pseudouridine synthases in bacteria and yeast. However, the mechanism of TRUB family underlying the formation of Ψ55 in the mammalian tRNAs is largely unknown. In this report, the CMC/reverse transcription assays demonstrated the presence of Ψ55 in the human mitochondrial tRNAAsn, tRNAGln, tRNAGlu, tRNAPro, tRNAMet, tRNALeu(UUR) and tRNASer(UCN). TRUB1 knockout (KO) cell lines generated by CRISPR/Cas9 technology exhibited the loss of Ψ55 modification in mitochondrial tRNAAsn, tRNAGln, tRNAGlu and tRNAPro but did not affect other 18 mitochondrial tRNAs. An in vitro assay revealed that recombinant TRUB1 protein can catalyze the efficient formation of Ψ55 in tRNAAsn and tRNAGln, but not in tRNAMet and tRNAArg. Notably, the overexpression of TRUB1 cDNA reversed the deficient Ψ55 modifications in these tRNAs in TRUB1KO HeLa cells. TRUB1 deficiency affected the base-pairing (18A/G-Ψ55), conformation and stability but not aminoacylation capacity of these tRNAs. Furthermore, TRUB1 deficiency impacted mitochondrial translation and biogenesis of oxidative phosphorylation system. Our findings demonstrated that human TRUB1 is a highly conserved mitochondrial pseudouridine synthase responsible for the Ψ55 modification in the mitochondrial tRNAAsn, tRNAGln, tRNAGlu and tRNAPro.


Assuntos
Transferases Intramoleculares , RNA de Transferência de Ácido Glutâmico , Animais , Humanos , RNA de Transferência de Glutamina , RNA de Transferência de Prolina , RNA de Transferência de Asparagina , RNA de Transferência de Metionina , Células HeLa , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Pseudouridina/genética , Pseudouridina/metabolismo , RNA de Transferência/metabolismo , Mamíferos/genética
12.
Eur Arch Otorhinolaryngol ; 281(3): 1371-1378, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38085304

RESUMO

OBJECTIVES: Medialization thyroplasty (MT) using various implants has been employed as a corrective procedure for unilateral vocal fold paralysis (UVFP). A newly developed APrevent® vocal implant system (VOIS) offers an innovative solution with a finely adjustable design. This study aimed to investigate the long-term functional voice outcomes and benefits of postoperative adjustments in patients receiving MT using the VOIS-implant. METHODS: This is a prospective case series study at single tertiary medical center. Fourteen adult patients diagnosed with UVFP received MT with the VOIS implant and were followed up for more than 1 year. Implant adjustment procedure by injecting 0.9% physiological saline solution was performed both during and after the surgery to optimize glottal closure and voice quality. Objective voice outcomes and acoustic parameters were assessed preoperatively and postoperatively at various timepoints. RESULTS: Thirteen patients (93%) received intraoperative balloon adjustment, ranging from 0.05to 0.12 ml. Four patients underwent adjustments postoperatively and exhibited a positive trend towards immediately improving acoustic voice quality. Our long-term results demonstrated a notable improvement after the surgery in voice quality, with significant decreases in VHI-30 and improvements in perceptual parameters of GRBAS scale, acoustic measures such as jitter and signal-to-noise ratio (p < 0.001) and cepstral peak prominence smoothed in sustained vowel and short sentences. The voice outcomes remained stable more than 1 year follow-up. CONCLUSIONS: Overall, MT with VOIS implantation provides a favorable long-term outcomes and stability in voice quality for patients with UVFP and also an effective tool for postoperative adjustment without major revision surgeries.


Assuntos
Laringoplastia , Paralisia das Pregas Vocais , Voz , Adulto , Humanos , Laringoplastia/métodos , Prega Vocal/cirurgia , Paralisia das Pregas Vocais/cirurgia , Qualidade da Voz , Resultado do Tratamento
13.
Mol Genet Genomics ; 298(6): 1493-1503, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37845373

RESUMO

Previous studies have observed relationships between immune cells and systemic lupus erythematosus (SLE), but their causal links remain undetermined. Based on the public available genome-wide association studies (GWAS) summary statistics, we conducted two-sample Mendelian randomization (MR) to evaluate the associations between 731 immune phenotypes and SLE pairs. Pairwise pleiotropy analysis was performed to identify pleiotropic genes for significant immunophenotype-SLE pairs. A comprehensive gene function analysis was undertaken to explore the mechanisms of immune cells in SLE. By using the instrumental variables extracted from GWAS data, we observed that increased levels of five immune phenotypes were causally associated with SLE risk (FDR < 0.05), that were CD20 on IgD+ CD38- naïve, BAFF-R on IgD+ CD38dim, CD39+ secreting Treg AC, CD14- CD16+ monocyte AC, and HLA DR on CD14+ monocyte. Pairwise gene-based analyses identified a total of 38 pleiotropic genes for 5 significant pairs identified and gene set enrichment analysis revealed the involvement of the identified pleiotropic genes in complex pathways (i.e., systemic lupus erythematosus, an integral component of luminal side of endoplasmic reticulum membrane, C-type lectin receptor signaling pathway and regulation of hormone secretion). This study demonstrates that the immune response influences the progression of SLE in a complex pattern. These findings greatly improve our understanding of the interaction between immune response and SLE risk and also aid in the design of therapeutic strategies from an immunological perspective.


Assuntos
Lúpus Eritematoso Sistêmico , Análise da Randomização Mendeliana , Humanos , Estudo de Associação Genômica Ampla , Fenótipo , Transdução de Sinais/genética , Lúpus Eritematoso Sistêmico/genética , Polimorfismo de Nucleotídeo Único
14.
J Biomed Sci ; 30(1): 82, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37737178

RESUMO

Mitochondria are essential organelles for cellular metabolism and physiology in eukaryotic cells. Human mitochondria have their own genome (mtDNA), which is maternally inherited with 37 genes, encoding 13 polypeptides for oxidative phosphorylation, and 22 tRNAs and 2 rRNAs for translation. mtDNA mutations are associated with a wide spectrum of degenerative and neuromuscular diseases. However, the pathophysiology of mitochondrial diseases, especially for threshold effect and tissue specificity, is not well understood and there is no effective treatment for these disorders. Especially, the lack of appropriate cell and animal disease models has been significant obstacles for deep elucidating the pathophysiology of maternally transmitted diseases and developing the effective therapy approach. The use of human induced pluripotent stem cells (iPSCs) derived from patients to obtain terminally differentiated specific lineages such as inner ear hair cells is a revolutionary approach to deeply understand pathogenic mechanisms and develop the therapeutic interventions of mitochondrial disorders. Here, we review the recent advances in patients-derived iPSCs as ex vivo models for mitochondrial diseases. Those patients-derived iPSCs have been differentiated into specific targeting cells such as retinal ganglion cells and eventually organoid for the disease modeling. These disease models have advanced our understanding of the pathophysiology of maternally inherited diseases and stepped toward therapeutic interventions for these diseases.


Assuntos
Células-Tronco Pluripotentes Induzidas , Animais , Humanos , Mutação , Mitocôndrias/genética , Diferenciação Celular , DNA Mitocondrial/genética
15.
J Biomed Sci ; 30(1): 63, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37537557

RESUMO

BACKGROUND: Leber's hereditary optic neuropathy (LHON) is a maternally inherited eye disease due to mutations in mitochondrial DNA. However, there is no effective treatment for this disease. LHON-linked ND6 14484T > C (p.M64V) mutation caused complex I deficiency, diminished ATP production, increased production of reactive oxygen species (ROS), elevated apoptosis, and impaired mitophagy. Here, we investigated if the allotopic expression of human mitochondrial ND6 transgene corrected the mitochondrial dysfunctions due to LHON-associated m.14484T > C mutation. METHODS: Nucleus-versions of ND6 was generated by changing 6 non-universal codons with universal codons and added to mitochondrial targeting sequence of COX8. Stable transfectants were generated by transferring human ND6 cDNA expressed in a pCDH-puro vector into mutant cybrids carrying the m.14484T > C mutation and control cybrids. The effect of allotopic expression of ND6 on oxidative phosphorylation (OXPHOS) was evaluated using Blue Native gel electrophoresis and extracellular flux analyzer. Assessment of ROS production in cell lines was performed by flow cytometry with MitoSOX Red reagent. Analyses for apoptosis and mitophagy were undertaken via flow cytometry, TUNEL and immunofluorescence assays. RESULTS: The transfer of human ND6 into the cybrids carrying the m.14484T > C mutation raised the levels of ND6, ND1 and ND4L but did not change the levels of other mitochondrial proteins. The overexpression of ND6 led to 20~23% increases in the assembly and activity of complex I, and ~ 53% and ~ 33% increases in the levels of mitochondrial ATP and ΔΨm in the mutant cybrids bearing m.14484T > C mutation. Furthermore, mutant cybrids with overexpression of ND6 exhibited marked reductions in the levels of mitochondrial ROS. Strikingly, ND6 overexpression markedly inhibited the apoptosis process and restored impaired mitophagy in the cells carrying m.14484T > C mutation. However, overexpression of ND6 did not affect the ND6 level and mitochondrial functions in the wild-type cybrids, indicating that this ND6 level appeared to be the maximum threshold level to maintain the normal cell function. CONCLUSION: We demonstrated that allotopic expression of nucleus-versions of ND6 restored complex I, apoptosis and mitophagy deficiencies caused by the m.14484T > C mutation. The restoration of m.14484T > C mutation-induced mitochondrial dysfunctions by overexpression of ND6 is a step toward therapeutic interventions for LHON and mitochondrial diseases.


Assuntos
NADH Desidrogenase , Atrofia Óptica Hereditária de Leber , Humanos , Trifosfato de Adenosina , Apoptose/genética , DNA Mitocondrial/genética , Mutação , Atrofia Óptica Hereditária de Leber/genética , Atrofia Óptica Hereditária de Leber/metabolismo , Espécies Reativas de Oxigênio , NADH Desidrogenase/genética
16.
Langmuir ; 39(2): 870-877, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36602256

RESUMO

Porous membranes with under-liquid dual superlyophobic properties, which are difficult to achieve because of a thermodynamic contradiction, have attracted considerable interest in the field of switchable oil/water separation. Herein, a bioinspired mesh membrane with alternating hydrophilic and hydrophobic chemical patterns on its surface that endows it with superamphiphilic and under-liquid dual superlyophobic properties is fabricated by a simple liquidus modification process. The as-prepared membrane possesses a combination of under-oil superhydrophobic and under-water superoleophobic characteristics in the absence of external stimuli. Moreover, it can effectively perform the on-demand separation of various oil/water systems, including immiscible oil/water mixtures and oil/water emulsions owing to its under-liquid dual superlyophobic properties.


Assuntos
Óleos , Óleos/química , Interações Hidrofóbicas e Hidrofílicas , Emulsões/química
17.
Neuroradiology ; 65(2): 381-390, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36269335

RESUMO

PURPOSE: To investigate thrombus age and its association with clinical and procedural parameters in patients with acute ischemic stroke (AIS) due to anterior circulation occlusions. METHODS: The thrombi of 107 consecutive AIS patients with occlusions in anterior circulation large-arteries were collected during mechanical recanalization. By hematoxylin-eosin staining analysis, thrombi were classified as fresh (< 3 days) or old (≥ 3 days) according to the hemosiderin positivity. Old thrombi were further classified as thrombi with focal hemosiderin or diffuse hemosiderin according to their predominant distribution. Neuro-interventional data and clinical outcomes were compared based on thrombus age. RESULTS: We identified fresh thrombi in 29 patients and old thrombi in 78 patients. Compared with patients with fresh thrombi, patients with old thrombi were associated with (i) a longer mechanical recanalization time (p = 0.027), (ii) a higher percentage of fibrin/platelets and leukocytes (all p = 0.02) and a lower percentage of erythrocytes (p = 0.001), and (iii) less favorable clinical outcomes at discharge (p = 0.019) and 90 days later (OR = 2.76, 95% CI = 1.09-6.99, p = 0.032). Furthermore, 18 (16.8%) of all patients had focal hemosiderin in old thrombi, which was independently linked to a poor clinical outcome 90 days later (adjusted OR = 5.37, 95% CI = 1.14-25.28, p = 0.034). CONCLUSION: The presence of old thrombi, particularly those with focal hemosiderin, may aid in identifying patients with acute ischemic anterior circulation stroke who are at a higher risk of poor clinical outcome at 3-month follow-up.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Trombose , Humanos , Hemossiderina , Trombectomia , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/cirurgia , Acidente Vascular Cerebral/complicações , Trombose/diagnóstico por imagem , Trombose/cirurgia , Resultado do Tratamento , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/cirurgia , Isquemia Encefálica/complicações
18.
Med Sci Monit ; 29: e937772, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37077040

RESUMO

BACKGROUND The role of nutritional parameter prealbumin in predicting the incidence of hepatic encephalopathy (HE) remains unclear. This study was designed to assess the diagnostic performance of prealbumin in predicting the incidence of HE in hepatitis B virus (HBV)-related decompensated liver cirrhosis patients. MATERIAL AND METHODS A retrospective cohort of 262 patients with HBV-related decompensated liver cirrhosis was involved in this study. Prealbumin, albumin, and other indicators were collected at admission, and independent factors were identified by logistic regression analysis. The Mann-Whitney U test and receiver operating characteristic (ROC) curves were used to compare the groups and indicators. RESULTS A total of 262 patients were enrolled in the study, including 197 men and 65 women. In patients with HBV-related decompensated liver cirrhosis accompanied by HE, the model for end-stage liver disease (MELD) scores, and prothrombin time (PT) and international normalized ratio (INR) values were significantly increased, while prealbumin and albumin levels were significantly decreased. Multivariate analysis showed that only serum prealbumin level (P=0.014) was independently related to the incidence of HE. Moreover, prealbumin level was negatively correlated with MELD (r=-0.63, P<0.001) and Child-Turcotte-Pugh (r=-0.35, P<0.001) scores. ROC curves were performed, and prealbumin showed the highest area under the ROC curve (0.781) compared with MELD and Child-Turcotte-Pugh scores. CONCLUSIONS Low prealbumin levels were associated with increased frequency of hepatic encephalopathy in HBV-related decompensated cirrhosis, which showed better performance than traditional models.


Assuntos
Doença Hepática Terminal , Encefalopatia Hepática , Masculino , Humanos , Feminino , Vírus da Hepatite B , Pré-Albumina , Encefalopatia Hepática/complicações , Estudos Retrospectivos , Doença Hepática Terminal/complicações , Cirrose Hepática , Índice de Gravidade de Doença , Albuminas , Curva ROC , Prognóstico
19.
Curr Microbiol ; 80(2): 79, 2023 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-36656344

RESUMO

Two aerobic, Gram-staining-positive, rod-shaped, endospore-forming, thermophilic bacterial strains, designated FJAT-47801T and FJAT-47835, were isolated from the sediment collected from Zhangjiang Estuary Mangrove National Nature Reserve in Fujian Province, China. Growth was observed at 25-55 °C (optimum, 50 °C) and pH 7.0-9.0 (optimum, pH 7.0), with up to 4.0% (w/v) NaCl (optimum, without NaCl). Strains FJAT-47801T and FJAT-47835 showed the highest 16S rRNA gene sequence similarity to Bacillus oleivorans (98.5%). The 16S rRNA gene sequence similarity between FJAT-47801T and FJAT-47835 was 99.9% indicating they were the same species. Phylogenetic (based on 16S rRNA gene sequences) and phylogenomic (based on 120 conserved bacterial single-copy genes) trees showed that strains FJAT-47801T and FJAT-47835 should be affiliated to the genus Bacillus. The of menaquinone of strain FJAT-47801T was MK-7. The major fatty acids of strain FJAT-47801T were iso-C15:0, anteiso-C15:0, iso-C17:0, and C16:0. The major polar lipids strain FJAT-47801T were phosphatidylethanolamine (PE), diphosphatidylglycerol (DPG), and phosphatidylglycerol (PG). The genomic DNA G+C content of strain FJAT-47801T was 39.3%. The average nucleotide identity (84.3%) and the digital DNA-DNA hybridization value (28.1%) between strain FJAT-47801T and B. oleivorans CCTCC AB 2013353T were below the cut-off level for species delineation. Based on the above results, strain FJAT-47801T represents a novel species of the genus Bacillus, for which the name Bacillus litorisediminis sp. nov., is proposed. The type strain is FJAT-47801T (=GDMCC 1.2712T = JCM 34875T).


Assuntos
Bacillus , Fosfolipídeos , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Cloreto de Sódio/análise , DNA Bacteriano/genética , DNA Bacteriano/análise , Microbiologia do Solo , Técnicas de Tipagem Bacteriana , Parede Celular/química , Ácido Diaminopimélico/análise , Ácido Diaminopimélico/química , Peptidoglicano/análise , Análise de Sequência de DNA , Ácidos Graxos/química
20.
Nucleic Acids Res ; 49(22): 13108-13121, 2021 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-34878141

RESUMO

Mutations in genes encoding mitochondrial aminoacyl-tRNA synthetases are linked to diverse diseases. However, the precise mechanisms by which these mutations affect mitochondrial function and disease development are not fully understood. Here, we develop a Drosophila model to study the function of dFARS2, the Drosophila homologue of the mitochondrial phenylalanyl-tRNA synthetase, and further characterize human disease-associated FARS2 variants. Inactivation of dFARS2 in Drosophila leads to developmental delay and seizure. Biochemical studies reveal that dFARS2 is required for mitochondrial tRNA aminoacylation, mitochondrial protein stability, and assembly and enzyme activities of OXPHOS complexes. Interestingly, by modeling FARS2 mutations associated with human disease in Drosophila, we provide evidence that expression of two human FARS2 variants, p.G309S and p.D142Y, induces seizure behaviors and locomotion defects, respectively. Together, our results not only show the relationship between dysfunction of mitochondrial aminoacylation system and pathologies, but also illustrate the application of Drosophila model for functional analysis of human disease-causing variants.


Assuntos
Deficiências do Desenvolvimento/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Proteínas Mitocondriais/genética , Mutação , Fenilalanina-tRNA Ligase/genética , RNA de Transferência/genética , Convulsões/genética , Animais , Linhagem Celular , Deficiências do Desenvolvimento/enzimologia , Modelos Animais de Doenças , Proteínas de Drosophila/deficiência , Drosophila melanogaster/enzimologia , Técnicas de Silenciamento de Genes , Humanos , Microscopia Eletrônica de Transmissão , Mitocôndrias/genética , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Proteínas Mitocondriais/deficiência , Fosforilação Oxidativa , Fenilalanina-tRNA Ligase/deficiência , RNA de Transferência/metabolismo , Convulsões/enzimologia , Aminoacilação de RNA de Transferência
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