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1.
Front Plant Sci ; 15: 1336229, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38384761

RESUMO

The HAP clade, mainly including Helichrysum Mill, Anaphalis DC., and Pseudognaphalium Kirp., is a major component of tribe Gnaphalieae (Asteraceae). In this clade, Anaphalis represents the largest genus of Asian Gnaphalieae. The intergeneric relationships among Anaphalis and its related genera and the infrageneric taxonomy of this genus are complex and remain controversial. However, there are few studies that have focused on these issues. Herein, based on the current most comprehensive sampling of the HAP clade, especially Anaphalis, we conducted phylogenetic analyses using chloroplast (cp) genome and nuclear ribosomal DNA (nrDNA) to evaluate the relationships within HAP clade, test the monophyly of Anaphalis, and examine the infrageneric taxonomy of this genus. Meanwhile, the morphological characters were verified to determine the circumscription and infrageneric taxonomy system of Anaphalis. Additionally, the biogeographical history, diversification processes, and evolution of crucial morphological characters were estimated and inferred. Our phylogenetic analyses suggested that Anaphalis is polyphyletic because it nested with Helichrysum and Pseudognaphalium. Two and four main clades of Anaphalis were identified in cp genome and nrDNA trees, respectively. Compared with nrDNA trees, the cp genome trees were more effective for phylogenetic resolution. After comprehensively analyzing morphological and phylogenetic evidence, it was concluded that the achene surface ornamentation and leaf base showed less homoplasy and supported the two Anaphalis lineages that were inferred from cp genome. Our biogeographical analyses based on cp genome indicated that HAP clade underwent rapid diversification from late Miocene to Pliocene. The two Anaphalis lineages appeared to have originated in Africa, then spread to Western and Southern Asia, and subsequently moved into Southwestern China forming a diversity center. The dispersal patterns of the two Anaphalis lineages were different. One dispersed around the world, except in Africa and South America. The other one dispersed to Eastern and Southeastern Asia from the ancestral origin region.

2.
Plant Divers ; 45(4): 409-421, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37601540

RESUMO

The genus Trigonotis comprises nearly 60 species mainly distributed in East and Southeast Asia. China has the largest number of Trigonotis species in the world, with a total of 44 species, of which 38 are endemic. Nutlet morphology is useful for the taxonomic delimitation of Trigonotis. However, there are still controversial circumscriptions of nutlet shape in some species. In previous studies, interspecies phylogenetic relationships were inferred using few DNA markers and very few taxa, which possibly led to erroneous or incomplete conclusions. In this study, the nutlet morphology of 39 Trigonotis taxa and the characteristics of 34 complete chloroplast genomes (29 taxa) were investigated and analyzed. Then, the phylogenetic relationships were discussed within this genus based on complete chloroplast genomes. To the best of our knowledge, this study is the first comprehensive analysis of nutlet morphology and complete chloroplast genome of Trigonotis. Based on nutlet morphology, Trigonotis can be divided into two groups: Group 1, hemispherical or oblique tetrahedron with carpopodiums, and Group 2, inverted tetrahedron without carpopodiums. The chloroplast genome of Trigonotis exhibited a typical quadripartite structure, including 84-86 protein-coding, 37 transfer RNA, and 8 ribosomal RNA genes, with a total length of 147,247-148,986 bp. Genes in the junctions were well conserved in Trigonotis, similar to those in other Boraginaceae s.str. species. Furthermore, Trigonotis chloroplast genomes showed relatively high diversity, with more conserved genic regions than intergenic regions; in addition, we detected 14 hot spots (Pi > 0.005) in non-coding regions. Phylogenetic analyses based on chloroplast genome data identified highly resolved relationships between Trigonotis species. Specifically, Trigonotis was divided into two clades with strong support: one clade included species with hemispherical or oblique tetrahedron nutlets with carpopodiums and bracts, whereas the other clade included species with inverted tetrahedron nutlets without carpopodiums or bracts. Our results may inform future taxonomic, phylogenetic, and evolutionary studies on Boraginaceae.

3.
Immunity ; 56(1): 58-77.e11, 2023 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-36521495

RESUMO

Obesity-induced chronic liver inflammation is a hallmark of nonalcoholic steatohepatitis (NASH)-an aggressive form of nonalcoholic fatty liver disease. However, it remains unclear how such a low-grade, yet persistent, inflammation is sustained in the liver. Here, we show that the macrophage phagocytic receptor TREM2, induced by hepatocyte-derived sphingosine-1-phosphate, was required for efferocytosis of lipid-laden apoptotic hepatocytes and thereby maintained liver immune homeostasis. However, prolonged hypernutrition led to the production of proinflammatory cytokines TNF and IL-1ß in the liver to induce TREM2 shedding through ADAM17-dependent proteolytic cleavage. Loss of TREM2 resulted in aberrant accumulation of dying hepatocytes, thereby further augmenting proinflammatory cytokine production. This ultimately precipitated a vicious cycle that licensed chronic inflammation to drive simple steatosis transition to NASH. Therefore, impaired macrophage efferocytosis is a previously unrecognized key pathogenic event that enables chronic liver inflammation in obesity. Blocking TREM2 cleavage to restore efferocytosis may represent an effective strategy to treat NASH.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Hipernutrição , Humanos , Hepatopatia Gordurosa não Alcoólica/patologia , Hipernutrição/patologia , Fígado/patologia , Inflamação/patologia , Obesidade/patologia , Glicoproteínas de Membrana , Receptores Imunológicos
4.
Biomedicines ; 10(6)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35740272

RESUMO

Inflammation, when properly mounted and precisely calibrated, is a beneficial process that enables the rapid removal of invading pathogens and/or cellular corpses and promotes tissue repair/regeneration to restore homeostasis after injury. Being a paradigm of a rapid response transcription factor, the nuclear factor-kappa B (NF-κB) transcription factor family plays a central role in amplifying inflammation by inducing the expression of inflammatory cytokines and chemokines. Additionally, NF-κB also induces the expression of pro-survival and -proliferative genes responsible for promoting tissue repair and regeneration. Paradoxically, recent studies have suggested that the NF-κB pathway can also exert inhibitory effects on pro-inflammatory cytokine production to temper inflammation. Here, we review our current understanding about the pro- and anti-inflammatory roles of NF-κB and discuss the implication of its dichotomous inflammation-modulating activity in the context of inflammasome activation and tumorigenesis.

5.
Cancer Med ; 10(15): 5235-5245, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34160902

RESUMO

BACKGROUND: Histone deacetylases (HDACs) have been demonstrated to be aberrantly activated in tumorigenesis and cancer development. Thus, HDAC inhibitors (HDACIs) are considered to be promising anti-cancer therapeutics. However, recent studies have shown that HDACIs promote the migration of many cancer cells. Therefore, there is a need to elucidate the underlying mechanisms of HDACIs on cancer cell migration to establish a combination therapy that overcomes HDACI-induced cell migration. METHODS: KYSE-150 and EC9706 cells were treated differently. Effects of drugs and siRNA treatment on tumor cell migration and cell signaling pathways were investigated by transwell migration assy. Gene expression for SNAI2 was tested by RT-qPCR. Western blot analysis was employed to detect the level of E-cadherin, ß-catenin, vimentin,Slug,ERK1/2, H3, PAI-1 and BRD4. The effect of drugs on cell morphology was evaluated through phase-contrast microscopic images. RESULTS: TSA promotes epithelial-mesenchymal transition (EMT) in ESCC cells by downregulating the epithelial marker E-cadherin and upregulating mesenchymal markers ß-catenin, vimentin, Slug, and PAI-1. Knockdown of Slug by siRNA or inhibition of PAI-1 clearly suppressed TSA-induced ESCC cell migration and resulted in the reversal of TSA-triggered E-cadherin, ß-catenin, and vimentin expression. However, no crosstalk between Slug and PAI-1 was observed in TSA-treated ESCC cells. Blocking ERK1/2 activation also inhibited TSA-induced ESCC cell migration, EMT, and upregulation of Slug and PAI-1 levels in ESCC cells. Interestingly, inhibition of BRD4 suppressed TSA-induced ESCC cell migration and attenuated TSA-induced ERK1/2 activation and upregulation of Slug and PAI-1 levels. CONCLUSIONS: Our data indicate the existence of at least two separable ERK1/2-dependent signaling pathways in TSA-mediated ESCC cell migration: an ERK1/2-Slug branch and an ERK1/2-PAI-1 branch. Both branches of TSA-induced ESCC cell migration appear to favor the EMT process, while BRD4 is responsible for two separable ERK1/2-dependent signaling pathways in TSA-mediated ESCC cell migration.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Ácidos Hidroxâmicos/farmacologia , Sistema de Sinalização das MAP Quinases/fisiologia , Fatores de Transcrição/metabolismo , Butadienos/farmacologia , Caderinas/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/fisiologia , Forma Celular/efeitos dos fármacos , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/metabolismo , Carcinoma de Células Escamosas do Esôfago/patologia , Flavonoides/farmacologia , Expressão Gênica , Inibidores de Histona Desacetilases/farmacologia , Histona Desacetilases/fisiologia , Humanos , Ácidos Hidroxâmicos/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nitrilas/farmacologia , Inibidor 1 de Ativador de Plasminogênio/metabolismo , Inibidores de Proteínas Quinases/farmacologia , RNA Interferente Pequeno , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo , Vimentina/metabolismo , beta Catenina/metabolismo
6.
PhytoKeys ; 187: 77-92, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35068969

RESUMO

Lappulasinaica was recently transferred to the monotypic genus Pseudolappula based on phylogenetic studies, while the related species, L.occultata, has remained in the genus Lappula. In this study, morphological, molecular, and palynological evidence supports that L.occultata should be transferred to the genus Pseudolappula. Both L.occultata and P.sinaica share a combination of nutlets features that distinguish them from Lappula: a longer adaxial keel and a linear attachment scar. Phylogenetic analysis based on ITS and trnL-F strongly supports L.occultata as the sister taxon of P.sinaica. In addition, pollen grains of these two species are 3-syncolporate with 3 alternating pseudocolpi, which is significantly different from the grains of Lappula taxa. Based on the above evidence, the new combination Pseudolappulaoccultata is proposed.

7.
Cell Mol Immunol ; 18(6): 1450-1462, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-31767975

RESUMO

Innate immunity plays a prominent role in the host defense against pathogens and must be precisely regulated. As vital orchestrators in cholesterol homeostasis, microRNA-33/33* have been widely investigated in cellular metabolism. However, their role in antiviral innate immunity is largely unknown. Here, we report that VSV stimulation decreased the expression of miR-33/33* through an IFNAR-dependent manner in macrophages. Overexpression of miR-33/33* resulted in impaired RIG-I signaling, enhancing viral load and lethality whereas attenuating type I interferon production both in vitro and in vivo. In addition, miR-33/33* specifically prevented the mitochondrial adaptor mitochondrial antiviral-signaling protein (MAVS) from forming activated aggregates by targeting adenosine monophosphate activated protein kinase (AMPK), subsequently impeding the mitophagy-mediated elimination of damaged mitochondria and disturbing mitochondrial homeostasis which is indispensable for efficient MAVS activation. Our findings establish miR-33/33* as negative modulators of the RNA virus-triggered innate immune response and identify a previously unknown regulatory mechanism linking mitochondrial homeostasis with antiviral signaling pathways.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenilato Quinase/metabolismo , Imunidade Inata , MicroRNAs/metabolismo , Vesiculovirus/imunologia , Animais , Antagomirs/farmacologia , Sequência de Bases , Proteína DEAD-box 58/metabolismo , Regulação para Baixo/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Células HEK293 , Células HeLa , Humanos , Imunidade Inata/efeitos dos fármacos , Interferon Tipo I/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/patologia , Macrófagos/virologia , Camundongos Endogâmicos C57BL , MicroRNAs/genética , Mitofagia/efeitos dos fármacos , Modelos Biológicos , Agregados Proteicos/efeitos dos fármacos , Receptor de Interferon alfa e beta/metabolismo , Receptores Imunológicos/metabolismo , Transdução de Sinais/efeitos dos fármacos
8.
Aging (Albany NY) ; 12(23): 24394-24423, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33260160

RESUMO

FBXW7 functions as an E3 ubiquitin ligase to mediate oncoprotein degradation via the ubiquitin-proteasome system in cancer cells, effectively inhibiting the growth and survival of tumor cells. However, little is known about the functions of FBXW7 in macrophages and the tumor immune microenvironment. In this study, we find that FBXW7 suppresses M2-like tumor-associated macrophage (TAM) polarization to limit tumor progression. We identified a significant increase in the proportion of M2-like TAMs and aggravated tumor growth in mice with myeloid FBXW7 deficiency by subcutaneous inoculation with Lewis lung carcinoma cells (LLCs). When stimulated with LLCs supernatant in vitro, FBXW7-knockout macrophages displayed increased M2 macrophage polarization and enhanced ability of supporting cancer cells growth. In mechanism, we confirmed that FBXW7 inhibited M2-like TAM polarization by mediating c-Myc degradation via the ubiquitin-proteasome system. These findings highlight the role of FBXW7 in M2-like TAM polarization and provide new insights into the potential targets for cancer immunotherapies.


Assuntos
Carcinoma Pulmonar de Lewis/enzimologia , Proteína 7 com Repetições F-Box-WD/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Macrófagos Associados a Tumor/enzimologia , Animais , Carcinoma Pulmonar de Lewis/genética , Carcinoma Pulmonar de Lewis/patologia , Proliferação de Células , Células Cultivadas , Proteína 7 com Repetições F-Box-WD/deficiência , Proteína 7 com Repetições F-Box-WD/genética , Regulação Neoplásica da Expressão Gênica , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fenótipo , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteólise , Proteínas Proto-Oncogênicas c-myc/genética , Transdução de Sinais , Carga Tumoral , Microambiente Tumoral , Macrófagos Associados a Tumor/patologia , Ubiquitinação
9.
Anticancer Drugs ; 31(6): 567-574, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32282366

RESUMO

Protein acetylation modification controlled by acetyltransferases (HATs) and histone deacetylases (HDACs) regulates multiple biologic processes including cell proliferation and migration. HDAC inhibitors (HDACi) are currently used as a promising epigenetic-based therapy for cancer treatment. Of the anticancer activity, accumulating evidence has shown that HDACi can enhance cell migration in subset of cancer cells. Thus, there is a critical need to identify such counter anticancer activity to HDACi in different cancer cell types and elucidate the rational in order to develop appropriate combination therapies in cancer treatment. In seeking to address the effect of HDACi on esophageal squamous cell carcinoma (ESCC) cells migration, trichostatin A (TSA), a canonical HDACi targeting class I and class II HDACs, was used. Here, we report the discovery that TSA augmented ESCC cells migration by increasing the acetylation of nuclear factor-κB/RelA at lysine 310 (K310). To elucidate the mechanism by which TSA promotes the migration of ESCC cells, plasmid of RelA K310R, a mutant precluding acetylation at K310, was transfected into ESCC cells. Blocking acetylation of RelA at K310 significantly arrogated TSA-induced cell migration. Mechanistic investigations revealed that TSA increased the level of acetylated RelA at K310 (RelA K310ac), thereby increasing the level of epithelia-mesenchymal transition (EMT) transcription factor slug mRNA, which in turn induced EMT. Overall, this study indicates that TSA promotes ESCC cells migration by RelA K310ac-slug-EMT pathway. Our findings provide a strategy to eradicate HDACi-induced ESCC cells migration by targeting RelA as a combination therapy with nonspecific HDACi in ESCC treatment.


Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ácidos Hidroxâmicos/farmacologia , Lisina/química , Fator de Transcrição RelA/metabolismo , Acetilação , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Movimento Celular , Proliferação de Células , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/tratamento farmacológico , Carcinoma de Células Escamosas do Esôfago/metabolismo , Inibidores de Histona Desacetilases/farmacologia , Humanos , Fator de Transcrição RelA/química , Fator de Transcrição RelA/genética , Células Tumorais Cultivadas
10.
Iran J Basic Med Sci ; 22(10): 1132-1137, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31998453

RESUMO

OBJECTIVES: Mitofilin contributes to the maintenance of mitochondrial structure and functions. This study was undertaken to determine the mechanisms underlying its regulation of apoptosis. MATERIALS AND METHODS: Mitofilin was knockdowned by specific short hairpin RNA (shRNA) and the stable HeLa cell clone was selected. The autophagy activity were assessed with LC3-II conversion and puncta formation by western blot and fluorescence imaging in starved and normal cultured HeLa cells. Autophagy flux was measured in the presence of NH4Cl. Wortmannin was used to inhibit autophagy. Cell viability and apoptosis were detected with cell counting kit-8 (CCK-8) and fluorescence-activated cell sorting (FACS) assay, respectively. RESULTS: Mitofilin expression was down-regulated in starved HeLa cells. In established mitofilin stable knockdown cell lines, LC3-II conversion and puncta formation were detected, which are both hallmarks of autophagy, under both basal and starvation conditions. Mitofilin down-regulation decreased LC3-II conversion and puncta formation, which indicates that loss of mitofilin function inhibits both basal and starvation-induced autophagy activity. CCK-8 and FACS analysis confirmed mitofilin involvement in the regulation of cell survival since mitofilin down-regulation facilitated starvation-induced apoptosis in HeLa cells. CONCLUSION: Taken together, mitofilin is a potent regulator of autophagy and it may modulate cell survival through regulation of autophagy.

11.
Biochim Biophys Acta Mol Basis Dis ; 1863(9): 2266-2273, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28559044

RESUMO

Our previous study generated a series of cybrids containing mitochondria of synaptosomes from mice at different ages. The following functional analysis on these cybrids revealed an age-dependent decline of mitochondrial function. To understand the underlying mechanisms that contribute to the age-related mitochondrial dysfunction, we focused on three cybrids carrying mitochondria derived from synaptosomes of the old mice that exhibited severe respiratory deficiencies. In particular, we started with a comprehensive analysis of mitochondrial genome by high resolution, high sensitive deep sequencing method. Compared with young control, we detected a significant accumulation of heteroplasmic mtDNA mutations. These mutations included six alterations in main control region that has been shown to regulate overall gene-expression, and four alterations in protein coding region, two of which led to significant changes in complex I subunit ND5 and complex III subunit CytB. Interestingly, a reduced mtDNA-encoded protein synthesis was associated with the changes in the main control region. Likewise, mutations in ND5 and CytB were associated with defects in assembly of respiratory complexes. Altogether, the identified age-dependent accumulation of mtDNA mutations in mouse brain likely contributes to the decline in mitochondrial function.


Assuntos
Envelhecimento/genética , DNA Mitocondrial/genética , Doenças Mitocondriais/genética , Mutação , Fosforilação Oxidativa , Envelhecimento/metabolismo , Animais , DNA Mitocondrial/metabolismo , Complexo I de Transporte de Elétrons/genética , Complexo I de Transporte de Elétrons/metabolismo , Complexo III da Cadeia de Transporte de Elétrons/genética , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Camundongos , Doenças Mitocondriais/metabolismo , Ratos
12.
Opt Express ; 24(1): 645-51, 2016 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-26832294

RESUMO

A highly sensitive magnetic field sensor based on a fiber ring laser has been proposed and experimentally demonstrated. The magnetic field sensor was fabricated by introducing a rotary apparatus modulated by an external magnetic field into the fiber cavity to twist one section of the fiber. Due to the remarkable birefringence change induced into the laser cavity, the beat frequency generated between two polarizations of the laser is sensitive to the variation of applied magnetic field intensity. Experimental results show that the polarization mode beat frequency linearly shifts with the increment of the magnetic field intensity and the sensitivity reaches up to 7.09 KHz/Oe in the range of 0 - 437 Oe. Therefore, it will be a promising candidate for the weak magnetic field applications including military, hazard forecast and biomedical fields.

13.
Biochem Biophys Res Commun ; 470(1): 226-232, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-26778000

RESUMO

MitoNEET is the first identified iron sulfur protein that located in the mitochondrial outer membrane. We showed that knockdown of mitoNEET did not affect the iron sulfur protein expression in mitochondria and cytoplasm, but significantly reduced the cytosolic aconitase activity. The reduction of aconitase activity was rescued by transfection of wild type mitoNEET, but not by mitoNEET mutants H87C and H87S. Our results confirm the observation that mitoNEET is important in transferring the iron sulfur clusters to the cytosolic aconitase in living cells and the His-87 ligand in mitoNEET plays important role in this process.


Assuntos
Aconitato Hidratase/metabolismo , Citosol/metabolismo , Histidina/metabolismo , Proteínas Ferro-Enxofre/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Sítios de Ligação , Transporte Biológico Ativo/fisiologia , Células Hep G2 , Histidina/química , Humanos , Células MCF-7 , Proteínas Mitocondriais/química , Ligação Proteica
14.
Opt Express ; 23(16): 20668-74, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26367919

RESUMO

An ultra-compact optical fiber magnetic field sensor based on a microstructured optical fiber (MOF) modal interference and ferrofluid (FF) has been proposed and experimentally demonstrated. The magnetic field sensor was fabricated by splicing a tapered germanium-doped index guided MOF with six big holes injected with FF to two conventional single-mode fibers. The transmission spectra of the proposed sensor under different magnetic field intensities have been measured and theoretically analyzed. Due to an efficient interaction between the magnetic nanoparticles in FF and the excited cladding mode, the magnetic field sensitivity reaches up to117.9pm/mT with a linear range from 0mT to 30mT. Moreover, the fabrication process of the proposed sensor is simple, easy and cost-effective. Therefore, it will be a promising candidate for military, aviation industry, and biomedical applications, especially, for the applications where the space is limited.

15.
Free Radic Biol Med ; 63: 30-40, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23643721

RESUMO

Mitochondrial respiratory chain defects have been associated with various diseases and with normal aging, particularly in tissues with high energy demands, including brain and skeletal muscle. Tissue-specific manifestation of mitochondrial DNA (mtDNA) mutations and mitochondrial dysfunction are hallmarks of mitochondrial diseases although the underlying mechanisms are largely unclear. Previously, we and others have established approaches for transferring mtDNA from muscle and synaptosomes of mice at various ages to cell cultures. In this study, we carried out a comprehensive bioenergetic analysis of cells bearing mitochondria derived from young, middle-aged, and old mouse skeletal muscles and synaptosomes. Significant age-associated alterations in oxidative phosphorylation and regulation during aging were observed in cybrids carrying mitochondria from both skeletal muscle and synaptosomes. Our results also revealed that loss of oxidative phosphorylation capacity may occur at various ages in muscle and brain. These findings indicate the existence of a tissue-specific regulatory mechanism for oxidative phosphorylation.


Assuntos
Envelhecimento/metabolismo , Mitocôndrias/metabolismo , Doenças Mitocondriais/metabolismo , Neurônios/metabolismo , Fosforilação Oxidativa , Envelhecimento/patologia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , DNA Mitocondrial , Metabolismo Energético , Humanos , Camundongos , Mitocôndrias/patologia , Doenças Mitocondriais/patologia , Mutação , Neurônios/patologia , Especificidade de Órgãos
16.
Wei Sheng Wu Xue Bao ; 53(1): 74-81, 2013 Jan 04.
Artigo em Chinês | MEDLINE | ID: mdl-23614243

RESUMO

OBJECTIVE: To study the relationship between CD4 + CD25 + Foxp3 + regulatory T cells and Th17 responses during pulmonary infection of Chlamydia muridarum (Cm) in BALB/c mice. [Methods] BALB/c mice aged 6-8 weeks were inoculated intranasally with 5 x 103 IFU of Cm to set up the murine model of Chlamydial pneumonia. The boet weight changes, the growth of Cm and the pathology in the lung were monitored at different time post-infection. In determine the CD4 + CD25 + Foxp3 + regulatory T cells responses in BALB/c mice, intracellular cytokine staining was used to assay the percentage of CD4 + CD25 + Foxp3 + T cells in the spleen and mediastinum lymph node (MLN). The production of cytokines/chemokines in the lung were monitored, including IL-6,TGF-beta,IL-17 ,IL-2 (by ELISA), K(C and MIP-2 (by RT-PCR). RESULTS: Intranasally infected with 5 x 10(3) IFU of Cm in mice resulted in chlamydial pneumonitis featured by body weight lost, chlamydia growth and pathological damage in the lung compared with their uninfected counterparts. On day 3 post-infection, the percentage of CD4 + CD25 + Foxp3 + T cells in the spleen and MLN were significantly decreased than the control mice; then began to increase and recover to the original level on day 7 post-infection. The production of Th17 associated cytokines/chemokines such as IL-6, IL-17, KCand MIP-2 increased, which peaked on day 7 post-infection, then gradually reduced. The production of TGF-beta and IL-2 was consistent with the trend of CD4 + CD25 + Foxp3 + T cells. CONCLUSION: During pulmonary infection of Cm in BALB/c mice, CD4 + CD25 + Foxp3 + regulatory T cells may promote type 17 T cell immunity through providing TGF-beta in the presence of IL-6.


Assuntos
Infecções por Chlamydia/imunologia , Chlamydia muridarum/fisiologia , Pneumopatias/imunologia , Linfócitos T Reguladores/imunologia , Células Th17/imunologia , Animais , Infecções por Chlamydia/microbiologia , Feminino , Humanos , Interleucina-2/imunologia , Interleucina-6/imunologia , Pneumopatias/microbiologia , Camundongos , Camundongos Endogâmicos BALB C
17.
Front Biosci (Elite Ed) ; 5(2): 734-47, 2013 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-23277028

RESUMO

Aging is a multifactorial process during which physiological alterations occur in all tissues. A decline in mitochondrial function plays an important role in the process of aging and in aging-associated diseases. The mitochondrial genome encodes 13 essential subunits of protein complexes belonging to the oxidative phosphorylation system, while most of the mitochondria-related genes are encoded by the nuclear genome. Coordination between the nucleus and mitochondria is crucial for the regulation of mitochondrial biogenesis and function. In this review, we will discuss aging-related mitochondrial dysfunction in various tissues and its implication in aging-related diseases and the aging process.


Assuntos
Envelhecimento/fisiologia , Encéfalo/fisiologia , Metabolismo Energético/fisiologia , Fígado/fisiologia , Redes e Vias Metabólicas/fisiologia , Mitocôndrias/fisiologia , Músculos/fisiologia , Células Sanguíneas/fisiologia , Ciclo Celular/fisiologia , Fibroblastos/fisiologia , Modelos Biológicos
18.
Adv Exp Med Biol ; 942: 39-51, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22399417

RESUMO

Mitochondria are the only organelles in animal cells which possess their own genomes. Mitochondrial DNA (mtDNA) alterations have been associated with various human conditions. Yet, their role in pathogenesis remains largely unclear. This review focuses on several major features of mtDNA: (1) mtDNA haplogroup, (2) mtDNA common deletion, (3) mtDNA mutations in the control region or D-loop, (4) mtDNA copy number alterations, (5) mtDNA mutations in translational machinery, (6) mtDNA mutations in protein coding genes (7) mtDNA heteroplasmy. We will also discuss their implications in various human diseases.


Assuntos
DNA Mitocondrial/fisiologia , DNA Mitocondrial/genética , Humanos , Mutação
19.
PLoS One ; 7(1): e29666, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22253756

RESUMO

Iron is essential for organisms. It is mainly utilized in mitochondria for biosynthesis of iron-sulfur clusters, hemes and other cofactors. Mitoferrin 1 and mitoferrin 2, two homologues proteins belonging to the mitochondrial solute carrier family, are required for iron delivery into mitochondria. Mitoferrin 1 is highly expressed in developing erythrocytes which consume a large amount of iron during hemoglobinization. Mitoferrin 2 is ubiquitously expressed, whose functions are less known. Zebrafish with mitoferrin 1 mutation show profound hypochromic anaemia and erythroid maturation arrests, and yeast with defects in MRS3/4, the counterparts of mitoferrin 1/2, has low mitochondrial iron levels and grows poorly by iron depletion. Mitoferrin 1 expression is up-regulated in yeast and mouse models of Fiedreich's ataxia disease and in human cell culture models of Parkinson disease, suggesting its involvement in the pathogenesis of diseases with mitochondrial iron accumulation. In this study we found that reduced mitoferrin levels in C. elegans by RNAi treatment causes pleiotropic phenotypes such as small body size, reduced fecundity, slow movement and increased sensitivity to paraquat. Despite these abnormities, lifespan was increased by 50% to 80% in N2 wild type strain, and in further studies using the RNAi sensitive strain eri-1, more than doubled lifespan was observed. The pathways or mechanisms responsible for the lifespan extension and other phenotypes of mitoferrin RNAi worms are worth further study, which may contribute to our understanding of aging mechanisms and the pathogenesis of iron disorder related diseases.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Transporte de Cátions/metabolismo , Longevidade/fisiologia , Sequência de Aminoácidos , Animais , Bioensaio , Tamanho Corporal/efeitos dos fármacos , Caenorhabditis elegans/anatomia & histologia , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/química , Proteínas de Caenorhabditis elegans/genética , Proteínas de Transporte de Cátions/química , Proteínas de Transporte de Cátions/genética , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Gônadas/anormalidades , Gônadas/efeitos dos fármacos , Gônadas/patologia , Humanos , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Longevidade/efeitos dos fármacos , Longevidade/genética , Camundongos , Dados de Sequência Molecular , Paraquat/toxicidade , Interferência de RNA/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
20.
Zhongguo Fei Ai Za Zhi ; 12(1): 54-8, 2009 Jan 20.
Artigo em Chinês | MEDLINE | ID: mdl-20712958

RESUMO

BACKGROUND: S100A7 is a member of S100 family and its overexpression has been previously associated with carcinogenesis of certain cancers. The aim of this study is to explore the expression of calcium-binding protein S100A7 in lung cancer. METHODS: In the present study, RT-PCR, Western-blot and immunohistochemistry were used to analyze the different expression of S100A7 in lung cancer tissues and paired noncancerous lung tissues. RESULTS: The specific expression of S100A7 was found in squamous cell carcinomas and large cell lung carcinomas, whereas it was not detected in adenocarcinomas, small cell carcinomas, other cell types of lung cancer and normal lung tissues as well as paired noncancerous lung tissues. CONCLUSIONS: S100A7 was selectively expressed in squamous cell carcinomas and large cell lung carcinomas and may serve as a potential marker for lung cancer diagnosis.

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