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1.
Nat Commun ; 11(1): 3803, 2020 07 30.
Artigo em Inglês | MEDLINE | ID: mdl-32732991

RESUMO

Microbial communities comprised of phototrophs and heterotrophs hold great promise for sustainable biotechnology. Successful application of these communities relies on the selection of appropriate partners. Here we construct four community metabolic models to guide strain selection, pairing phototrophic, sucrose-secreting Synechococcus elongatus with heterotrophic Escherichia coli K-12, Escherichia coli W, Yarrowia lipolytica, or Bacillus subtilis. Model simulations reveae metabolic exchanges that sustain the heterotrophs in minimal media devoid of any organic carbon source, pointing to S. elongatus-E. coli K-12 as the most active community. Experimental validation of flux predictions for this pair confirms metabolic interactions and potential production capabilities. Synthetic communities bypass member-specific metabolic bottlenecks (e.g. histidine- and transport-related reactions) and compensate for lethal genetic traits, achieving up to 27% recovery from lethal knockouts. The study provides a robust modelling framework for the rational design of synthetic communities with optimized growth sustainability using phototrophic partners.


Assuntos
Bacillus subtilis/metabolismo , Escherichia coli/metabolismo , Processos Heterotróficos/fisiologia , Processos Fototróficos/fisiologia , Synechococcus/metabolismo , Yarrowia/metabolismo , Aldeídos/metabolismo , Bacillus subtilis/genética , Reatores Biológicos/microbiologia , Escherichia coli/genética , Etanol/metabolismo , Formaldeído/metabolismo , Metanol/metabolismo , Microbiota/fisiologia , Modelos Biológicos , Ácido Succínico/metabolismo , Synechococcus/genética , Yarrowia/genética
2.
J Breath Res ; 14(4): 041001, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32531777

RESUMO

The COVID-19 pandemic has highlighted the importance of rapid, cost effective, accurate, and non-invasive testing for viral infections. Volatile compounds (VCs) have been suggested for several decades as fulfilling these criteria. However currently very little work has been done in trying to diagnose viral infections using VCs. Much of the work carried out to date involves the differentiation of bacterial and viral sources of infection and often the detection of bacterial and viral co-infection. However, this has usually been done in vitro and very little work has involved the use of human participants. Viruses hijack the host cell metabolism and do not produce their own metabolites so identifying virus specific VCs is at best a challenging task. However, there are proteins and lipids that are potential candidates as markers of viral infection. The current understanding is that host cell glycolysis is upregulated under viral infection to increase the available energy for viral replication. There is some evidence that viral infection leads to the increase of production of fatty acids, alkanes, and alkanes related products. For instance, 2,3-butandione, aldehydes, 2,8-dimethyl-undecane and n-propyl acetate have all been correlated with viral infection. Currently, the literature points to markers of oxidative stress (e.g. nitric oxide, aldehydes etc) being the most useful in the determination of viral infection. The issue, however, is that there are also many other conditions that can lead to oxidative stress markers being produced. In this review a range of (mainly mass spectrometric) methods are discussed for viral detection in breath, including breath condensate. Currently MALDI-ToF-MS is likely to be the preferred method for the identification of viral strains and variants of those strains, however it is limited by its need for the viral strains to have been sequenced and logged in a database.


Assuntos
Testes Respiratórios/métodos , Viroses/diagnóstico , Aldeídos/metabolismo , Animais , Betacoronavirus , Biomarcadores/metabolismo , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Hepatite B/diagnóstico , Hepatite B/metabolismo , Humanos , Influenza Humana/diagnóstico , Influenza Humana/metabolismo , Espectrometria de Massas , Óxido Nítrico/metabolismo , Infecções por Orthomyxoviridae/diagnóstico , Infecções por Orthomyxoviridae/metabolismo , Estresse Oxidativo , Pandemias , Infecções por Picornaviridae/diagnóstico , Infecções por Picornaviridae/metabolismo , Pneumonia Viral/diagnóstico , Pneumonia Viral/metabolismo , Infecções por Rotavirus/diagnóstico , Infecções por Rotavirus/metabolismo , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Suínos , Viroses/metabolismo , Vírus
3.
J Pharmacol Sci ; 143(3): 188-198, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32414691

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is a chronic disease that causes morbidity associated with metabolic syndrome. NAFLD is a worldwide problem and represents a major cause of liver injury, which can lead to liver cell death. We investigated the effects of nonivamide (pelargonic acid vanillylamide, PAVA; 1 mg/kg) and rosuvastatin (RSV; 10 mg/kg) on hepatic steatosis induced by a high-fat diet (HFD). Male Sprague-Dawley rats were fed a HFD for 16 weeks then received PAVA or RSV for 4 additional weeks. We examined the metabolic parameters, function, fat content, histological alterations, reactive oxygen species production, and apoptotic cell death of the liver, in addition to the expression of the following important molecules: transient receptor potential cation channel subfamily V member 1 (TRPV1) phosphorylation of sterol regulatory element binding protein (pSREBP-1c/SREBP-1c), total and membrane glucose transporter 2 (GLUT2), 4-hydroxynonenal (4-HNE), and cleaved caspase-3. HFD-induced hepatic steatosis was associated with significantly increased morphological disorganization, injury markers, oxidative stress, lipid peroxidation, and apoptosis. However, metabolic dysfunction and hepatic injury were reduced by RSV and PAVA treatment. PAVA regulated lipid deposition, improved insulin resistance, and decreased oxidative stress and apoptotic cell death. Therefore, PAVA represents a promising therapeutic approach for treating metabolic disorders in patients with NAFLD.


Assuntos
Capsaicina/análogos & derivados , Capsicum/química , Dieta Hiperlipídica/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Fitoterapia , Aldeídos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Capsaicina/administração & dosagem , Capsaicina/isolamento & purificação , Capsaicina/farmacologia , Caspase 3/metabolismo , Transportador de Glucose Tipo 2/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos Sprague-Dawley , Rosuvastatina Cálcica/administração & dosagem , Rosuvastatina Cálcica/farmacologia , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Canais de Cátion TRPV/metabolismo
4.
Life Sci ; 253: 117705, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32334008

RESUMO

AIMS: Ischemia-reperfusion injury (IRI) is harmful to patients following kidney transplantation. Hypothermic machine perfusion (HMP) can be adopted to preserve grafts and reduce consequential injury. We hypothesized that aldehyde dehydrogenase 2 (ALDH2) partly mitigates kidney IRI via regulating excessive autophagy in HMP. MATERIALS AND METHODS: The rabbits were assigned to 5 groups: Normal, HMP, HMP + Alda-1, HMP + CYA and cold storage (CS). After the rabbit autologous kidney transplantation, renal pathology and function were evaluated by histological analysis, glomerular related proteins (desmin, nephrin), tubular injury factors (NGAL, Ki67), serum creatinine (Cr) and blood urea nitrogen (BUN). Oxidative stress molecular Malondialdehyde (MDA) and superoxide dismutase (SOD2) expression, as well as inflammatory cytokines (TNF-α, IL-6, IL-10) were assessed by immunohistochemistry. The expression of LC3, p62, ALDH2, p-Akt, mTOR, PTEN, p-PTEN, and 4-HNE were measured by immunohistochemistry, RT-PCR, Western blot analysis or ELISA. KEY FINDINGS: HMP was more effective than CS for kidney preservation, with p- ALDH2 expressed in greater quantities in HMP. The results of kidney pathology and function in HMP + Alda-1 were the best. The MDA & SOD2 and the Vyacheslav score were improved in HMP + CYA. ALDH2 reduced 4-HNE-induced oxidative stress, inflammatory infiltration, the expression of LC3, p62 and inhibited autophagy accompanied by activation of p-Akt and mTOR via p-PTEN/PTEN. SIGNIFICANCE: Akt-mTOR autophagy pathway is a novel target for ALDH2 to reduce renal IRI partly by inhibition of 4-HNE in HMP, then protecting the donated kidney received after cardiac death (DCD).


Assuntos
Hipotermia Induzida/métodos , Transplante de Rim/métodos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Serina-Treonina Quinases TOR/metabolismo , Aldeído-Desidrogenase Mitocondrial/metabolismo , Aldeídos/metabolismo , Animais , Autofagia/fisiologia , Creatinina/sangue , Citocinas/metabolismo , Rim/irrigação sanguínea , Rim/patologia , Rim/cirurgia , Masculino , Estresse Oxidativo/fisiologia , Coelhos
5.
Arch Biochem Biophys ; 685: 108355, 2020 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-32268137

RESUMO

Psoriasis is a skin disease characterized by abnormal keratinocyte proliferation and inflammation. Currently, there are no cures for this disease, so the goal of treatment is to decrease inflammation and slow down the associated rapid cell growth and shedding. Recent advances have led to the usage of phosphodiesterase 4 (PDE4) inhibitors for treatment of this condition. For example, apremilast is an oral, selective PDE4 inhibitor that is able to reduce skin inflammation and is Food and Drug Administration (FDA)-approved to treat adults with moderate to severe psoriasis and/or psoriatic arthritis. However, common target-related adverse events, including diarrhea, nausea, headache, and insomnia limit the usage of this drug. To circumvent these effects, the usage of PDE4 inhibitors specifically designed for topical treatment, such as CHF6001, may combine local anti-inflammatory activity with limited systemic exposure, improving tolerability. In this study, we showed that CHF6001, currently undergoing clinical development for COPD, suppresses human keratinocyte proliferation as assessed via BrdU incorporation. We also observed decreased re-epithelialization in a scratch-wound model after CHF6001 treatment. At the molecular level, CHF6001 inhibited translocation of phosphorylated NF-κB subunit p65, promoting loss of nuclear cyclin D1 accumulation and an increase of cell cycle inhibitor p21. Furthermore, CHF6001 decreased oxidative stress, measured by assessing lipid peroxidation (4-HNE adduct formation), through the inactivation of the NADPH oxidase. These results suggest that CHF6001 has the potential to treat skin disorders associated with hyperproliferative keratinocytes, such as psoriasis by targeting oxidative stress, abnormal re-epithelization, and inflammation.


Assuntos
Proliferação de Células/efeitos dos fármacos , Queratinócitos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Inibidores da Fosfodiesterase 4/farmacologia , Sulfonamidas/farmacologia , para-Aminobenzoatos/farmacologia , Aldeídos/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ciclina D1/metabolismo , Humanos , NADPH Oxidases/metabolismo , Inibidores da Fosfodiesterase 4/toxicidade , Psoríase/tratamento farmacológico , Sulfonamidas/toxicidade , Fator de Transcrição RelA/metabolismo , para-Aminobenzoatos/toxicidade
6.
Nat Commun ; 11(1): 1426, 2020 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188856

RESUMO

Acetaldehyde-alcohol dehydrogenase (AdhE) enzymes are a key metabolic enzyme in bacterial physiology and pathogenicity. They convert acetyl-CoA to ethanol via an acetaldehyde intermediate during ethanol fermentation in an anaerobic environment. This two-step reaction is associated to NAD+ regeneration, essential for glycolysis. The bifunctional AdhE enzyme is conserved in all bacterial kingdoms but also in more phylogenetically distant microorganisms such as green microalgae. It is found as an oligomeric form called spirosomes, for which the function remains elusive. Here, we use cryo-electron microscopy to obtain structures of Escherichia coli spirosomes in different conformational states. We show that spirosomes contain active AdhE monomers, and that AdhE filamentation is essential for its activity in vitro and function in vivo. The detailed analysis of these structures provides insight showing that AdhE filamentation is essential for substrate channeling within the filament and for the regulation of enzyme activity.


Assuntos
Álcool Desidrogenase/química , Álcool Desidrogenase/metabolismo , Aldeído Oxirredutases/química , Aldeído Oxirredutases/metabolismo , Aldeídos/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Escherichia coli/enzimologia , Etanol/metabolismo , Álcool Desidrogenase/genética , Aldeído Oxirredutases/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Modelos Moleculares
7.
Arch Biochem Biophys ; 684: 108297, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32035098

RESUMO

Although rheumatoid arthritis (RA) has long posed a major threat to global health, the mechanisms driving the development and progression of RA remain incompletely understood. In the present study, we investigated the effects of G protein-coupled receptor 43 (GPR43/FFAR2) in various aspects of the pathogenesis of RA. To our knowledge, this is the first study to demonstrate that GPR43 is expressed on human fibroblast-like synoviocytes (FLS). Furthermore, we show that GPR43 is upregulated in FLS exposed to tumor necrosis factor-α (TNF-α). Importantly, our findings demonstrate that activation of GPR43 using its specific agonist significantly suppressed expression of the following key factors of RA: cytokines, such as interleukin-6 (IL-6), IL-8, high mobility group protein 1 (HMG-1); chemokines, such as monocyte chemoattractant protein 1 (MCP-1), intercellular adhesion molecule 1 (ICAM-1), and vascular cellular adhesion molecule 1 (VCAM-1); markers of oxidative stress, such as production of reactive oxygen species (ROS) and 4-hydroxynoneal (4-HNE); degradative enzymes, such as matrix metalloproteinase-3 (MMP-3) and MMP-13; and activation of the nuclear factor-κB (NF-κB) inflammatory signaling pathway. These results suggest a promising potential role for GPR43 as a specific target in the treatment and prevention of RA.


Assuntos
Receptores de Superfície Celular/metabolismo , Sinoviócitos/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Células A549 , Aldeídos/metabolismo , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Quimiocinas/metabolismo , Humanos , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 3 da Matriz/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Receptores de Superfície Celular/agonistas , Transdução de Sinais/efeitos dos fármacos , Tiazóis/farmacologia , Regulação para Cima/efeitos dos fármacos
8.
Oxid Med Cell Longev ; 2020: 7468738, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32064028

RESUMO

Cardiac arrest (CA) yields poor neurological outcomes. Salubrinal (Sal), an endoplasmic reticulum (ER) stress inhibitor, has been shown to have neuroprotective effects in both in vivo and in vitro brain injury models. This study investigated the neuroprotective mechanisms of Sal in postresuscitation brain damage in a rodent model of CA. In the present study, rats were subjected to 6 min of CA and then successfully resuscitated. Either Sal (1 mg/kg) or vehicle (DMSO) was injected blindly 30 min before the induction of CA. Neurological status was assessed 24 h after CA, and the cortex was collected for analysis. As a result, we observed that, compared with the vehicle-treated animals, the rats pretreated with Sal exhibited markedly improved neurological performance and cortical mitochondrial morphology 24 h after CA. Moreover, Sal pretreatment was associated with the following: (1) upregulation of superoxide dismutase activity and a reduction in maleic dialdehyde content; (2) preserved mitochondrial membrane potential; (3) amelioration of the abnormal distribution of cytochrome C; and (4) an increased Bcl-2/Bax ratio, decreased cleaved caspase 3 upregulation, and enhanced HIF-1α expression. Our findings suggested that Sal treatment improved neurological dysfunction 24 h after CPR (cardiopulmonary resuscitation), possibly through mitochondrial preservation and stabilizing the structure of HIF-1α.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Córtex Cerebelar/efeitos dos fármacos , Cinamatos/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Parada Cardíaca/fisiopatologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Tioureia/análogos & derivados , Aldeídos/metabolismo , Animais , Apoptose/efeitos dos fármacos , Lesões Encefálicas/complicações , Lesões Encefálicas/metabolismo , Lesões Encefálicas/fisiopatologia , Reanimação Cardiopulmonar , Caspase 3/metabolismo , Córtex Cerebelar/metabolismo , Córtex Cerebelar/fisiopatologia , Córtex Cerebelar/ultraestrutura , Citocromos c/metabolismo , Parada Cardíaca/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase-1/metabolismo , Tioureia/farmacologia
9.
Mol Cell Biochem ; 467(1-2): 27-43, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32060784

RESUMO

Epidemiological evidences have shown an association of exposure to pesticides or heavy metals with increased incidences of Parkinson's disease (PD) in humans. Exposure to pesticides or metals during the decisive period of the brain development increases the susceptibility of dopaminergic neurons upon re-exposure in adult rodents. However, the effect of early life exposure to pesticide on the heavy metal-induced neurodegeneration or heavy metal on pesticide-induced neurodegeneration is not yet explored. The current study explored the effect of developmental exposure to zinc (Zn), a metal or paraquat (PQ), a pesticide on the nigrostriatal dopaminergic neurons of rats challenged to Zn or PQ during adulthood. Exposure of Zn or PQ during adulthood alone exhibited marked reduction in motor activities, striatal dopamine and metabolites, glutathione content and number of dopaminergic neurons. However, the levels of lipid peroxidation, protein carbonyls, superoxide dismutase activity, pro-inflammatory cytokines and 4-hydroxynonenal-protein adducts were increased. While the expression of vesicular monoamine transporter-2 and tyrosine hydroxylase were attenuated, dopamine transporter and microglial marker Iba-1 expression, activated microglia, nuclear factor-kappa B activation, mitochondrial cytochrome c release and caspase-3/9 activation were augmented following Zn or PQ exposure. Albeit postnatal alone exposure did not alter any of the studied parameters, the developmental administration of Zn/PQ in re-challenged adult rats produced more pronounced changes in the aforementioned variables as compared with adulthood Zn or PQ alone intoxicated animals. The results demonstrate that postnatal Zn/PQ intoxication dents the oxidative stress, inflammation, cell death and dopamine metabolism and storage regulating machineries, which speed up the toxicant-induced degeneration during adulthood.


Assuntos
Neurônios Dopaminérgicos/citologia , Doenças Neurodegenerativas/metabolismo , Paraquat/efeitos adversos , Zinco/efeitos adversos , Aldeídos/metabolismo , Animais , Animais Recém-Nascidos , Sobrevivência Celular/efeitos dos fármacos , Citocinas/metabolismo , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Glutationa/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Doenças Neurodegenerativas/induzido quimicamente , Estresse Oxidativo/efeitos dos fármacos , Ratos , Superóxido Dismutase/metabolismo
10.
Artigo em Inglês | MEDLINE | ID: mdl-32058896

RESUMO

Cold-acclimation is essential for the development of adequate frost-hardiness in cereals and therefore sudden freezes can cause considerable damage to the canopy. However, timely adding of an appropriate signal in the absence of cold acclimation may also harden wheat for the upcoming freeze. The feasibility of the promising signal molecule methylglyoxal was tested here for such applications and the signal mechanism was studied in bread wheat (Triticum aestivum L.) and durum wheat (Triticum turgidum L. ssp. durum). Spraying with 10 mM methylglyoxal did not decrease the fresh weight and photosynthetic parameters in most wheat varieties at growth temperature (21 °C). Photosynthetic parameters even improved and chlorophyll content increased in some cases. Increased transcript level of glutathione-S-transferases and omega-3 fatty acid desaturases was detected by qPCR 6 h after the last methylglyoxal spray. Aldo-keto reductase and glyoxalase enzyme activities, as well as sorbitol content of wheat plants increased 24 h after the last 10 mM methylglyoxal spray in most of the cultivars. These mechanisms may explain the increased freezing survival of methylglyoxal pretreated wheat plants from less than 10% to over 30%. Our results demonstrate that exogenous methylglyoxal treatment can be safely added to wheat plants as preparatory treatment without detrimental effects but inducing some of the stress-protective mechanisms, which contribute to frost-hardiness.


Assuntos
Aldeídos , Congelamento , Aldeído Pirúvico , Triticum , Adaptação Fisiológica/efeitos dos fármacos , Aldeídos/metabolismo , Fotossíntese , Aldeído Pirúvico/farmacologia , Triticum/efeitos dos fármacos
11.
Food Chem ; 314: 126037, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31954941

RESUMO

This study aimed to investigate the effect of fermentation with Lactobacillus plantarum NCU137 on the nutritional, sensory and stability properties of Coix (Coix lachryma-jobi L.) seed. The nutritional compounds, including free amino acid, free fatty acid, soluble dietary fiber and organic acids of fermented coix seed were significantly (p < 0.05) increased than those of non-fermented coix seed. The fermented coix seed exhibiting a special flavor, due to the production of acids, the decreased level of aldehydes and ketones, and the increased level of alcohols in the volatile compounds, whereas the amount of hazardous substance 2-pentylfuran was reduced and natural antiseptic hexanoic acid was produced. The increased viscosity together with the larger particle size and the reduced absolute ζ potential contribute to the stability of the fermented coix seed paste system. Therefore, fermentation with L. plantarum NCU137 could improve the nutritional, sensory and stability properties of coix seed.


Assuntos
Coix/química , Coix/microbiologia , Lactobacillus plantarum/metabolismo , Sementes/química , Sementes/microbiologia , Álcoois/análise , Álcoois/metabolismo , Aldeídos/análise , Aldeídos/metabolismo , Aminoácidos/análise , Coix/metabolismo , Fermentação , Microbiologia de Alimentos , Armazenamento de Alimentos , Furanos/metabolismo , Cetonas/análise , Cetonas/metabolismo , Valor Nutritivo , Sementes/metabolismo , Compostos Orgânicos Voláteis
12.
Cell Death Dis ; 11(1): 73, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996668

RESUMO

Our preliminary work has revealed that vitamin D receptor (VDR) activation is protective against cisplatin induced acute kidney injury (AKI). Ferroptosis was recently reported to be involved in AKI. Here in this study, we investigated the internal relation between ferroptosis and the protective effect of VDR in cisplatin induced AKI. By using ferroptosis inhibitor ferrostatin-1 and measurement of ferroptotic cell death phenotype in both in vivo and in vitro cisplatin induced AKI model, we observed the decreased blood urea nitrogen, creatinine, and tissue injury by ferrostatin-1, hence validated the essential involvement of ferroptosis in cisplatin induced AKI. VDR agonist paricalcitol could both functionally and histologically attenuate cisplatin induced AKI by decreasing lipid peroxidation (featured phenotype of ferroptosis), biomarker 4-hydroxynonenal (4HNE), and malondialdehyde (MDA), while reversing glutathione peroxidase 4 (GPX4, key regulator of ferroptosis) downregulation. VDR knockout mouse exhibited much more ferroptotic cell death and worsen kidney injury than wild type mice. And VDR deficiency remarkably decreased the expression of GPX4 under cisplatin stress in both in vivo and in vitro, further luciferase reporter gene assay showed that GPX4 were target gene of transcription factor VDR. In addition, in vitro study showed that GPX4 inhibition by siRNA largely abolished the protective effect of paricalcitol against cisplatin induced tubular cell injury. Besides, pretreatment of paricalcitol could also alleviated Erastin (an inducer of ferroptosis) induced cell death in HK-2 cell. These data suggested that ferroptosis plays an important role in cisplatin induced AKI. VDR activation can protect against cisplatin induced renal injury by inhibiting ferroptosis partly via trans-regulation of GPX4.


Assuntos
Lesão Renal Aguda/metabolismo , Antineoplásicos/toxicidade , Cisplatino/toxicidade , Ferroptose/genética , Mitocôndrias/metabolismo , Receptores de Calcitriol/metabolismo , Lesão Renal Aguda/induzido quimicamente , Lesão Renal Aguda/enzimologia , Lesão Renal Aguda/genética , Aldeídos/metabolismo , Animais , Morte Celular/genética , Linhagem Celular , Creatinina/metabolismo , Cicloexilaminas/farmacologia , Ergocalciferóis/farmacologia , Ferroptose/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Humanos , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão e Varredura , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Fenilenodiaminas/farmacologia , Piperazinas/metabolismo , RNA Interferente Pequeno , Receptores de Calcitriol/agonistas , Receptores de Calcitriol/genética
13.
J Biol Chem ; 295(5): 1338-1349, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-31914410

RESUMO

The genetic context in bacterial genomes and screening for potential substrates can help identify the biochemical functions of bacterial enzymes. The Gram-negative, strictly anaerobic bacterium Veillonella ratti possesses a gene cluster that appears to be related to l-fucose metabolism and contains a putative dihydrodipicolinate synthase/N-acetylneuraminate lyase protein (FucH). Here, screening of a library of 2-keto-3-deoxysugar acids with this protein and biochemical characterization of neighboring genes revealed that this gene cluster encodes enzymes in a previously unknown "route I" nonphosphorylating l-fucose pathway. Previous studies of other aldolases in the dihydrodipicolinate synthase/N-acetylneuraminate lyase protein superfamily used only limited numbers of compounds, and the approach reported here enabled elucidation of the substrate specificities and stereochemical selectivities of these aldolases and comparison of them with those of FucH. According to the aldol cleavage reaction, the aldolases were specific for (R)- and (S)-stereospecific groups at the C4 position of 2-keto-3-deoxysugar acid but had no structural specificity or preference of methyl groups at the C5 and C6 positions, respectively. This categorization corresponded to the (Re)- or (Si)-facial selectivity of the pyruvate enamine on the (glycer)aldehyde carbonyl in the aldol-condensation reaction. These properties are commonly determined by whether a serine or threonine residue is positioned at the equivalent position close to the active site(s), and site-directed mutagenesis markedly modified C4-OH preference and selective formation of a diastereomer. I propose that substrate specificity of 2-keto-3-deoxysugar acid aldolases was convergently acquired during evolution and report the discovery of another l-2-keto-3-deoxyfuconate aldolase involved in the same nonphosphorylating l-fucose pathway in Campylobacter jejuni.


Assuntos
Aldeído Liases/metabolismo , Aldeídos/metabolismo , Fucose/metabolismo , Veillonella/enzimologia , Aldeído Liases/química , Aldeído Liases/genética , Aldeídos/química , Sequência de Aminoácidos/genética , Sítios de Ligação/genética , Campylobacter jejuni/enzimologia , Campylobacter jejuni/genética , Campylobacter jejuni/metabolismo , Domínio Catalítico/genética , Desoxiaçúcares/química , Desoxiaçúcares/metabolismo , Evolução Molecular , Hidroliases/química , Hidroliases/metabolismo , Cinética , Modelos Moleculares , Família Multigênica/genética , Mutagênese Sítio-Dirigida , Mutação , Oxo-Ácido-Liases/química , Oxo-Ácido-Liases/metabolismo , Filogenia , Especificidade por Substrato/genética , Veillonella/genética , Veillonella/metabolismo
14.
Chemosphere ; 244: 125482, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31812766

RESUMO

Aldehydes are common air pollutants and metabolites of the organism, which widely exist in many in vivo (e.g. Alzheimer's disease) and in vitro (e.g. cigarette smoke) situations. Individual aldehydes have been studied well alone, while their combined toxicity is still obscure. Here, we examined the combined apoptosis of aldehyde mixtures in BEAS-2B cells at smoking-related environmental/physiologically relevant concentrations, and the potential mechanism was investigated further based on the related signaling pathway. Co-exposure to aldehyde mixtures demonstrated significant synergistic interaction on apoptosis in a concentration-dependent manner, which differed from the expectation based on single aldehydes. Moreover, formaldehyde significantly potentiated the induction of death receptor-5, caspase 8/10, cleaved caspase 3/7/9, pro-apoptotic proteins (Bim, Bad and Bax), depolarization of MMP (mitochondrial membrane potential) and AIF (apoptosis-inducing factor) induced by acrolein, and synergistically decreased expressions of pro-survival proteins (Bcl-2 and Bcl-XL) and poly ADP-ribose polymerase. Therefore, aldehyde mixture-induced synergistic apoptosis was mediated both by TRAIL death receptor and mitochondrial pathway. Additionally, reactive oxygen species, Ca2+ levels, DNA damage, and phosphorylated MDM2 were all synergistically induced by aldehyde mixtures, while total p53, phosphorylated p53 and phosphorylated AKT (serine/threonine kinase) were inhibited. Antioxidants N-acetylcysteine suppressed the aldehyde mixture-induced ROS, DNA damage and apoptosis, and blocked the TRAIL death receptor and mitochondrial pathway, while it did not rescue the p53 and AKT pathway. Briefly, aldehyde mixtures induced synergistic apoptosis even at smoking-related environmental/physiologically relevant concentrations, which could be enhanced through ROS-mediated death receptor/mitochondrial pathway, and the down-regulation of phosphorylated AKT.


Assuntos
Aldeídos/toxicidade , Substâncias Perigosas/toxicidade , Testes de Toxicidade , Acroleína , Aldeídos/metabolismo , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Caspase 3 , Caspase 8 , Regulação para Baixo/efeitos dos fármacos , Células Epiteliais/metabolismo , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2 , Espécies Reativas de Oxigênio/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF
15.
Insect Biochem Mol Biol ; 116: 103260, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31682920

RESUMO

Most moths utilize sex pheromones released by the female to attract a mate. Females produce the sex pheromone in the pheromone gland in a biosynthetic pathway which consists of several key enzymes. Fatty acyl-CoA reductase is one of the key enzymes, which catalyzes the conversion of fatty acyl-CoA to the corresponding alcohol, playing an important role in producing the final proportion of each pheromone component. In Helicoverpa zea, (Z)-11-hexadecenal is the major sex pheromone component in female pheromone glands and previously a large amount of hexadecanal was also found in female and male tarsi. In our previous study, we compared the transcriptome between pheromone glands and tarsi and found 20 fatty acyl-CoA reductases in both tissues. In this study, we functionally characterized four FARs which were expressed at high levels according to the transcriptome of pheromone glands and tarsi. Fatty acyl-CoA reductase 1 was homologous to other moth pheromone gland specific fatty acyl-CoA reductases, and it was also present in male tarsi. Functional expression in yeast cells indicates that only fatty acyl-CoA reductase 1 was able to produce fatty alcohols. In addition, a decreased mRNA level of fatty acyl-CoA reductase 1 in female pheromone glands and male tarsi by RNAi knockdown caused a significant decrease in the production of (Z)-11-hexadecenal in pheromone glands and hexadecanal in male tarsi. This study is the first to demonstrate the direct function of a fatty acyl-CoA reductase in male tarsi and also confirms its role in sex pheromone biosynthesis in H. zea.


Assuntos
Aldeído Oxirredutases/genética , Proteínas de Insetos/genética , Mariposas/metabolismo , Aldeído Oxirredutases/química , Aldeído Oxirredutases/metabolismo , Aldeídos/metabolismo , Sequência de Aminoácidos , Animais , Tornozelo , Glândulas Exócrinas/química , Feminino , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Larva/crescimento & desenvolvimento , Larva/metabolismo , Masculino , Mariposas/crescimento & desenvolvimento , Filogenia , Alinhamento de Sequência , Atrativos Sexuais/biossíntese , Transcriptoma
16.
Cancer Sci ; 111(1): 127-136, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31692172

RESUMO

The major cellular antioxidant glutathione (GSH) protects cancer cells from oxidative damage that can lead to the induction of ferroptosis, an iron-dependent form of cell death triggered by the aberrant accumulation of lipid peroxides. Inhibitors of the cystine-glutamate antiporter subunit xCT, which mediates the uptake of extracellular cystine and thereby promotes GSH synthesis, are thus potential anticancer agents. However, the efficacy of xCT-targeted therapy has been found to be diminished by metabolic reprogramming that affects redox status in cancer cells. Identification of drugs for combination with xCT inhibitors that are able to overcome resistance to xCT-targeted therapy might thus provide the basis for effective cancer treatment. We have now identified the vasodilator oxyfedrine (OXY) as a sensitizer of cancer cells to GSH-depleting agents including the xCT inhibitor sulfasalazine (SSZ). Oxyfedrine contains a structural motif required for covalent inhibition of aldehyde dehydrogenase (ALDH) enzymes, and combined treatment with OXY and SSZ was found to induce accumulation of the cytotoxic aldehyde 4-hydroxynonenal and cell death in SSZ-resistant cancer cells both in vitro and in vivo. Microarray analysis of tumor xenograft tissue showed cyclooxygenase-2 expression as a potential biomarker for the efficacy of such combination therapy. Furthermore, OXY-mediated ALDH inhibition was found to sensitize cancer cells to GSH depletion induced by radiation therapy in vitro. Our findings thus establish a rationale for repurposing of OXY as a sensitizing drug for cancer treatment with agents that induce GSH depletion.


Assuntos
Aldeídos/metabolismo , Sistema y+ de Transporte de Aminoácidos/metabolismo , Antineoplásicos/farmacologia , Oxifedrina/farmacologia , Vasodilatadores/farmacologia , Aldeído Desidrogenase/metabolismo , Animais , Antioxidantes/metabolismo , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Glutationa/metabolismo , Células HCT116 , Humanos , Camundongos , Camundongos Nus , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Sulfassalazina/farmacologia
17.
Food Chem ; 303: 125424, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472384

RESUMO

The aim of our study was to investigate the effect of drop shock on physiological responses and genes expression in harvested apple fruit stored at 20 ±â€¯2 °C. Ethylene production, respiratory rate, firmness, soluble solid content, relative electrical conductivity, LOX (lipoxygenase) activity, MDA (malondialdehyde) content, variation of volatile compounds, ethylene biosynthetic genes, and ethylene receptor genes of apple fruit were examined. The results indicated that drop shock observably resulted in the increase of ethylene production, respiratory rate, soluble solid content, relative electrical conductivity, LOX activity, MDA content and gene expression levels in apples. Furthermore, drop shock significantly decreased firmness and high-intensitive drop shock stimulated the accumulation of aldehydes and esters in harvested apples. Overall, the greater impact on apple quality is the effect of larger amplitude of shock during truck transportation, which seriously reduced storage life and quality of postharvest apples.


Assuntos
Frutas/química , Malus/genética , Proteínas de Plantas/genética , Aldeídos/metabolismo , Fenômenos Biomecânicos , Ésteres/metabolismo , Etilenos/metabolismo , Frutas/genética , Frutas/metabolismo , Regulação da Expressão Gênica de Plantas , Lipoxigenase/genética , Lipoxigenase/metabolismo , Malondialdeído/metabolismo , Malus/química , Malus/metabolismo , Proteínas de Plantas/metabolismo , Controle de Qualidade
18.
Meat Sci ; 160: 107956, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31677433

RESUMO

The 3-methyl-butanal and 3-methyl-butanoic acid are known as fingerprint compounds from Staphylococcus aureus. In this study, we investigated production of these two volatile biomarkers and their correlation to S. aureus growth in pork. Both 3-methyl-butanal and 3-methyl-butanoic acid presented high specificity for S. aureus in either media or pork. In sterile minced pork and pork broth, production of volatile biomarkers and the growth of S. aureus were significantly correlated for most single cultures. However, for mixed cultures, only 3-methyl-butanoic acid indicated correlations with growth of S. aureus. Similar trending was also discovered in raw pork, where production of 3-methyl-butanoic acid was significantly correlated with the growth of S. aureus, but not for 3-methyl-butanal. In summary, 3-methyl-butanoic acid was a more stable metabolic marker than 3-methyl-butanal which could be used as an indicator for the presence of S. aureus in pork. This rapid, convenient and cost-effective detection approach could be applied in meat industry to achieve specific detection of S. aureus.


Assuntos
Aldeídos/metabolismo , Hemiterpenos/metabolismo , Ácidos Pentanoicos/metabolismo , Carne de Porco/microbiologia , Staphylococcus aureus/metabolismo , Animais , Biomarcadores/metabolismo , Microbiologia de Alimentos , Produtos da Carne/análise , Produtos da Carne/microbiologia , Carne de Porco/análise , Staphylococcus aureus/crescimento & desenvolvimento , Suínos
19.
Enzyme Microb Technol ; 132: 109415, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31731965

RESUMO

Aldo-keto reductases (AKRs) are nicotinamide-dependent enzymes that catalyze the transformation of aldehydes and ketones into alcohols. They are spread across all phyla, and those from microbial origin have proved to be highly robust and versatile biocatalysts. In this work, we have discovered and characterized a microbial AKR from the yeast Rhodotorula mucilaginosa by combining genome-mining and expression assays. The new enzyme, named AKR3B4, was expressed by a simple protocol in very good amounts. It displays a selective substrate profile exclusively transforming aldehydes into alcohols. Also, AKR3B4 shows very good stability at medium temperatures, in a broad range of pH values and in the presence of green organic solvents. Conversion assays demonstrate it is an excellent biocatalyst to be used in the synthesis of aromatic alcohols, and also to produce furan-3-ylmethanol and the valuable sweetener xylitol. These results show that AKR3B4 displays attractive features so as to be used in chemoenzymatic processes.


Assuntos
Aldo-Ceto Redutases/genética , Aldo-Ceto Redutases/metabolismo , Rhodotorula/enzimologia , Rhodotorula/genética , Oxirredutases do Álcool/metabolismo , Álcoois/metabolismo , Aldeído Redutase/metabolismo , Aldeídos/metabolismo , Clonagem Molecular , Enzimas , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Especificidade por Substrato
20.
J Biotechnol ; 307: 55-62, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31545972

RESUMO

Carboxylic acid reductases (CARs) are attracting burgeoning attention as biocatalysts for organic synthesis of aldehydes and their follow-up products from economic carboxylic acid precursors. The CAR enzyme class as a whole, however, is still poorly understood. To date, relatively few CAR sequences have been reported, especially from fungal sources. Here, we sought to increase the diversity of the CAR enzyme class. Six new CAR sequences from the white-rot fungus Pycnoporus cinnabarinus were identified from genome-wide mining. Genome and gene clustering analysis suggests that these PcCAR enzymes play different natural roles in Basidiomycete systems, compared to their type II Ascomycete counterparts. The cDNA sequences of all six Pccar genes were deduced and analysis of their corresponding amino acid sequence showed that they encode for proteins of similar properties that possess a conserved modular functional tri-domain arrangement. Phylogenetic analyses showed that all PcCAR enzymes cluster together with the other type IV CARs. One candidate, PcCAR4, was cloned and over-expressed recombinantly in Escherichia coli. Subsequent biotransformation-based screening with a panel of structurally-diverse carboxylic acid substrates suggest that PcCAR4 possessed a more pronounced substrate specificity compared to previously reported CARs, preferring to reduce sterically-rigid carboxylic acids such as benzoic acid. These findings thus present a new functionally-distinct member of the CAR enzyme class.


Assuntos
Oxirredutases/metabolismo , Pycnoporus/enzimologia , Aldeídos/metabolismo , Ácidos Carboxílicos/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Fúngicas/classificação , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Oxirredutases/classificação , Oxirredutases/genética , Filogenia , Pycnoporus/genética , Especificidade por Substrato , Trametes/metabolismo
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