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1.
Pediatr Dermatol ; 41(3): 455-457, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38303143

RESUMO

The nummular phenotype of atopic dermatitis is clinically characterized by pruritic, coin-shaped plaques that are frequently recalcitrant to treatment. In this study, a retrospective chart review was conducted to evaluate the effectiveness and safety of dupilumab in children with nummular lesions of dermatitis. Twelve out of 14 patients demonstrated significant clinical improvement at a median time of 2.5 months (interquartile range, 1-4) after dupilumab initiation. A single case of paradoxical psoriasiform eruption was the only side effect reported in our cohort.


Assuntos
Anticorpos Monoclonais Humanizados , Dermatite Atópica , Fenótipo , Humanos , Dermatite Atópica/tratamento farmacológico , Anticorpos Monoclonais Humanizados/uso terapêutico , Criança , Masculino , Estudos Retrospectivos , Feminino , Pré-Escolar , Resultado do Tratamento , Adolescente
2.
Pediatr Dermatol ; 41(2): 260-262, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38193388

RESUMO

Urticaria in infants can cause significant anxiety in parents, especially if a trigger cannot be identified. In a retrospective study of 246 infants seen for urticaria of unknown etiology at Boston Children's Hospital, 88.2% had resolution of urticaria within 6 weeks. The etiology of urticaria was ultimately established in 62.6% (72/115) of acute urticaria and 12.5% (2/16) of chronic urticaria cases with follow-up data. Pediatric healthcare providers can counsel families that while etiology of urticaria is never determined in over 40% of infants, symptoms are most likely to resolve spontaneously.


Assuntos
Urticária , Lactente , Criança , Humanos , Estudos Retrospectivos , Urticária/diagnóstico , Urticária/epidemiologia , Urticária/etiologia , Ansiedade , Boston/epidemiologia , Doença Crônica
3.
Biol Res ; 56(1): 40, 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37438821

RESUMO

BACKGROUND: Polar microalgae contain unique compounds that enable them to adapt to extreme environments. As the skin barrier is our first line of defense against external threats, polar microalgae extracts may possess restorative properties for damaged skin, but the potential of microalgae extracts as skin protective agents remains unknown. PURPOSE: This study aimed to analyze compound profiles from polar microalgae extracts, evaluate their potential as skin epithelial protective agents, and examine the underlying mechanisms. METHODS: Six different polar microalgae, Micractinium sp. (KSF0015 and KSF0041), Chlamydomonas sp. (KNM0029C, KSF0037, and KSF0134), and Chlorococcum sp. (KSF0003), were collected from the Antarctic or Arctic regions. Compound profiles of polar and non-polar microalgae extracts were analyzed using gas chromatography-mass spectrometry (GC-MS). The protective activities of polar microalgae extracts on human keratinocyte cell lines against oxidative stress, radiation, and psoriatic cytokine exposure were assessed. The potential anti-inflammatory mechanisms mediated by KSF0041, a polar microalga with protective properties against oxidative stress, ultraviolet (UV) B, and an inflammatory cytokine cocktail, were investigated using RNA-sequencing analysis. To evaluate the therapeutic activity of KSF0041, an imiquimod-induced murine model of psoriatic dermatitis was used. RESULTS: Polar microalgae contain components comparable to those of their non-polar counterparts, but also showed distinct differences, particularly in fatty acid composition. Polar microalgae extracts had a greater ability to scavenge free radicals than did non-polar microalgae and enhanced the viability of HaCaT cells, a human keratinocyte cell line, following exposure to UVB radiation or psoriatic cytokines. These extracts also reduced barrier integrity damage and decreased mRNA levels of inflammatory cytokines in psoriatic HaCaT cells. Treatment with KSF0041 extract altered the transcriptome of psoriatic HaCaT cells toward a more normal state. Furthermore, KSF0041 extract had a therapeutic effect in a mouse model of psoriasis. CONCLUSIONS: Bioactive compounds from polar microalgae extracts could provide novel therapeutics for damaged and/or inflamed skin.


Assuntos
Dermatite , Microalgas , Humanos , Animais , Camundongos , Queratinócitos , Citocinas , Substâncias Protetoras , Inflamação , Extratos Vegetais/farmacologia
4.
Mar Drugs ; 21(8)2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37623735

RESUMO

Polar microorganisms produce biologically active compounds that enable them to survive in harsh environments. These compounds have potential biomedical applications. The green microalga Chlamydomonas latifrons KNF0041, isolated from Arctic sea ice, has been found to produce polyunsaturated fatty acids (PUFAs), including omega-3 and omega-6, which have antioxidant properties. To improve the biomass production of strain KNF0041, statistical methods such as the Plackett-Burman design, Box-Behnken design, and response surface methodology (RSM) were utilized for medium optimization. The optimized medium was designed with increased potassium phosphate content and reduced acetic acid (AcOH) content. The use of the optimized medium resulted in an increase in the cell number as biomass of strain KNF0041 by 34.18% and the omega-3 and omega-6 fatty acid (FA) content by 10.04% and 58.29%, respectively, compared to that in normal TAP medium, which is known as the growth medium for Chlamydomonas culture. In this study, Chlamydomonas latifrons was discovered for the first time in the polar region and identified using morphology and molecular phylogenetic analyses, the secondary structures of the internal transcribed spacers, and optimized culture conditions. The results of this study provide an efficient method for the application of polar microalgae for the production of bioactive compounds.


Assuntos
Chlamydomonas , Ácidos Graxos Ômega-3 , Microalgas , Biomassa , Camada de Gelo , Filogenia
5.
Molecules ; 28(24)2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-38138572

RESUMO

Although cannabidiol and tetrahydrocannabinol in Cannabis species exert their pharmacological effects via the endocannabinoid system, it is believed that other phytochemicals, particularly terpenes, can modulate therapeutic outcomes through the entourage effect. Therefore, to gain a better understanding of the pharmacological effects of Cannabis, obtaining information on phytochemical compositions, including mono-, di-, and sesqui-terpenes in Cannabis species is essential. Applying a sophisticated analytical method is indispensable. In this study, headspace-gas chromatography/mass spectrometry (HS-GC/MS) was employed to identify major terpenes in the leaves and inflorescences of hybrid Cannabis species. The incubation time and temperature conditions for HS-GC/MS were optimized. This method was successfully applied to the leaves (n = 9) and inflorescences (n = 7) of hybrid Cannabis species. A total of 26 terpenes in Cannabis species were detected, and six major components, such as α-pinene (9.8-2270 µg/g), ß-pinene (2.6-930 µg/g), myrcene (0.7-17,400 µg/g), limonene (1.3-300 µg/g), ß-caryophyllene (60-3300 µg/g), and α-humulene (40-870 µg/g), were quantified. Each sample showed different terpene compositions, but six major terpenes among all the terpenes detected were consistently found in both the leaves and inflorescences of hybrid Cannabis species. In this study, the six major terpenes' potential in hybrid Cannabis species was evaluated as biomarkers to distinguish hybrid Cannabis species samples. This study contributes to a better understanding of the entourage effect of Cannabis-based botanical drugs.


Assuntos
Cannabis , Alucinógenos , Terpenos/análise , Cannabis/química , Inflorescência/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Limoneno/análise , Alucinógenos/análise , Agonistas de Receptores de Canabinoides , Compostos Fitoquímicos
6.
Environ Res ; 212(Pt A): 113233, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35390302

RESUMO

Ice-binding proteins (IBPs), originating from Arctic or Antarctic microorganisms, have freeze-inhibiting characteristics, allowing these organisms to survive in polar regions. Despite their significance in polar environments, the mechanism through which IBPs affect the chemical reactions in ice by controlling ice crystal formation has not yet been reported. In this study, a new mechanism for iodide (I-) activation into triiodide (I3-), which is the abundant iodine species in seawater, by using hydrogen peroxide (H2O2) in a frozen solution with IBPs was developed. A significant enhancement of I- activation into I3- was observed in the presence of Arctic-yeast-originating extracellular ice-binding glycoprotein (LeIBP) isolated from Leucosporidium sp. AY30, and a further increase in the I3- concentration was observed with the introduction of H2O2 to the frozen solution (25 times higher than in the aqueous solution after 24 h of reaction). The reaction in the ice increased with an increase in LeIBP concentration. The in-situ pH measurement in ice using cresol red (CR) revealed protons accumulated in the ice grain boundaries by LeIBP. However, the presence of LeIBP did not influence the acidity of the ice. The enhanced freeze concentration effect of H2O2 by LeIBP indicated that larger ice granules were formed in the presence of LeIBP. The results suggest that LeIBP affects the formation and morphology of ice granules, which reduces the total volume of ice boundaries throughout the ice. This leads to an increased local concentration of I- and H2O2 within the ice grain boundaries. IBP-assisted production of gaseous iodine in a frozen environment provides a previously unrecognized formation mechanism of active iodine species in the polar regions.


Assuntos
Basidiomycota , Iodo , Proteínas Anticongelantes/química , Proteínas Anticongelantes/farmacologia , Basidiomycota/química , Basidiomycota/metabolismo , Congelamento , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Peróxido de Hidrogênio , Gelo , Iodetos
7.
Adv Exp Med Biol ; 1395: 357-362, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36527662

RESUMO

Previously, anti-CD3 antibodies delivered intravenously have been known for their negative side effects. The experimental conditions for optimal liquid production are derived from the Fc-directed conjugation of anti-CD3 foralumab antibodies and magnetic nanoparticles (Ab-MNPs). The anti-CD3 antibodies are prepared for conjugation with MNPs using SiteClick antibody labelling kits. The successful conjugation of the Ab-MNPs is confirmed using a transmission electron microscopy (TEM) image and an energy dispersive spectroscopy (EDS) analysis. The average values ​​of the moving speed of MNPs and Ab-MNPs in phosphate buffer saline (PBS) were + 3.16 pix/frame and + 6.70 pix/frame in the x-axis, respectively. This implies that MNPs with CD3 antibodies attached to the surface through biocompatible ligand functional groups has better fluidity in PBS. Afterwards, a non-clinical animal testing for the flow characteristics of Ab-MNPs inside a blood vessel is carried out to observe the effects of Ab-MNP delivery through intravenous injection.


Assuntos
Nanopartículas de Magnetita , Animais , Nanopartículas de Magnetita/química , Magnetismo , Microscopia Eletrônica de Transmissão , Fenômenos Físicos , Anticorpos Monoclonais
8.
Mar Drugs ; 20(9)2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-36135751

RESUMO

The intestine and skin provide crucial protection against the external environment. Strengthening the epithelial barrier function of these organs is critical for maintaining homeostasis against inflammatory stimuli. Recent studies suggest that polar marine algae are a promising bioactive resource because of their adaptation to extreme environments. To investigate the bioactive properties of polar marine algae on epithelial cells of the intestine and skin, we created extracts of the Antarctic macroalgae Himantothallus grandifolius, Plocamium cartilagineum, Phaeurus antarcticus, and Kallymenia antarctica, analyzed the compound profiles of the extracts using gas chromatography-mass spectrometry, and tested the protective activities of the extracts on human intestinal and keratinocyte cell lines by measuring cell viability and reactive oxygen species scavenging. In addition, we assessed immune responses modulated by the extracts by real-time polymerase chain reaction, and we monitored the barrier-protective activities of the extracts on intestinal and keratinocyte cell lines by measuring transepithelial electrical resistance and fluorescence-labeled dextran flux, respectively. We identified bioactive compounds, including several fatty acids and lipid compounds, in the extracts, and found that the extracts perform antioxidant activities that remove intracellular reactive oxygen species and scavenge specific radicals. Furthermore, the Antarctic marine algae extracts increased cell viability, protected cells against inflammatory stimulation, and increased the barrier integrity of cells damaged by lipopolysaccharide or ultraviolet radiation. These results suggest that Antarctic marine algae have optimized their composition for polar environments, and furthermore, that the bioactive properties of compounds produced by Antarctic marine algae can potentially be used to develop therapeutics to promote the protective barrier function of the intestine and skin.


Assuntos
Antioxidantes , Phaeophyceae , Regiões Antárticas , Antioxidantes/farmacologia , Dextranos , Ácidos Graxos , Humanos , Lipopolissacarídeos , Recursos Naturais , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio , Raios Ultravioleta
9.
Pediatr Dermatol ; 38(4): 977-979, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34101255

RESUMO

A virtual pediatric dermatology student-run clinic was initiated during the COVID-19 pandemic, when in-person educational opportunities were limited. The clinic's aim is to provide high-quality dermatologic care to a diverse, underserved pediatric patient population while teaching trainees how to diagnose and manage common skin conditions. In our initial eight sessions, we served 37 patients, predominantly those with skin of color, and had a low no-show rate of 9.8%. This report describes the general structure of the clinic, goals, and the patient population to provide an overview of our educational model for those interested in similar efforts.


Assuntos
COVID-19 , Dermatologia , Educação Médica , Telemedicina , Criança , Dermatologia/educação , Humanos , Pandemias , Assistência ao Paciente , SARS-CoV-2 , Estudantes
11.
Circ Res ; 120(5): 848-861, 2017 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-28003219

RESUMO

RATIONALE: Direct conversion or reprogramming of human postnatal cells into endothelial cells (ECs), bypassing stem or progenitor cell status, is crucial for regenerative medicine, cell therapy, and pathophysiological investigation but has remained largely unexplored. OBJECTIVE: We sought to directly reprogram human postnatal dermal fibroblasts to ECs with vasculogenic and endothelial transcription factors and determine their vascularizing and therapeutic potential. METHODS AND RESULTS: We utilized various combinations of 7 EC transcription factors to transduce human postnatal dermal fibroblasts and found that ER71/ETV2 (ETS variant 2) alone best induced endothelial features. KDR+ (kinase insert domain receptor) cells sorted at day 7 from ER71/ETV2-transduced human postnatal dermal fibroblasts showed less mature but enriched endothelial characteristics and thus were referred to as early reprogrammed ECs (rECs), and did not undergo maturation by further culture. After a period of several weeks' transgene-free culture followed by transient reinduction of ER71/ETV2, early rECs matured during 3 months of culture and showed reduced ETV2 expression, reaching a mature phenotype similar to postnatal human ECs. These were termed late rECs. While early rECs exhibited an immature phenotype, their implantation into ischemic hindlimbs induced enhanced recovery from ischemia. These 2 rECs showed clear capacity for contributing to new vessel formation through direct vascular incorporation in vivo. Paracrine or proangiogenic effects of implanted early rECs played a significant role in repairing hindlimb ischemia. CONCLUSIONS: This study for the first time demonstrates that ER71/ETV2 alone can directly reprogram human postnatal cells to functional, mature ECs after an intervening transgene-free period. These rECs could be valuable for cell therapy, personalized disease investigation, and exploration of the reprogramming process.


Assuntos
Técnicas de Reprogramação Celular/métodos , Células Endoteliais/fisiologia , Fibroblastos/fisiologia , Fatores de Transcrição/biossíntese , Animais , Diferenciação Celular/fisiologia , Células Cultivadas , Membro Posterior/irrigação sanguínea , Membro Posterior/fisiologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Isquemia/metabolismo , Masculino , Camundongos , Camundongos Nus , Neovascularização Fisiológica/fisiologia , Fatores de Transcrição/genética
12.
Int J Med Sci ; 16(2): 189-197, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30745798

RESUMO

Inflammation triggered by the innate immune system is a strategy to protect organisms from the risk of environmental infection. However, it has recently become clear that inflammation can cause a variety of human diseases, including cancer. In this study, we investigated the effects of an ethanol extract of the Antarctic freshwater microalgae, Chloromonas reticulata (ETCH), on inflammation and carcinogenesis in RAW 264.7 macrophages and HCT116 human colon cancer cells, respectively. ETCH exhibited significant anti-inflammatory activity through the dose-dependent modulation of major inflammatory markers such as COX-2, IL-6, iNOS, TNF-α, and NO production. For example, ETCH reduced LPS-induced upregulation of COX-2, IL-6, iNOS, and TNF- alpha mRNA levels, leading to a significant decrease in the levels of LPS-stimulated NO and IL-6 as well as TNF-alpha products. In contract, ETCH exhibited dose-dependent cytotoxic activity against HCT116 cells, yielding a profound reduction in the proliferation of the cancer cells. Furthermore, ETCH induced G2 phase cell cycle arrest by transcriptionally regulating of genes involved in G2 / M transition including p21 (CDKN1A), cyclin B1 (CCNB1), and CDK1; CDKN1A mRNA levels were upregulated in response to ETCH, whereas CCNB1 and CDK1 were downregulated. This study reports for the first time anti-inflammatory and anti-cancer effects of, C. reticulata and provides new insights into the molecular mechanisms of the linkage between inflammation and cancer.


Assuntos
Produtos Biológicos/uso terapêutico , Inflamação/terapia , Microalgas , Neoplasias/prevenção & controle , Animais , Produtos Biológicos/farmacologia , Ciclo Celular/efeitos dos fármacos , Ciclo-Oxigenase 2/metabolismo , Citocinas/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Células HCT116 , Humanos , Lipopolissacarídeos , Camundongos , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Células RAW 264.7
14.
Int J Med Sci ; 15(9): 929-936, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30008606

RESUMO

Inflammation mediated by the innate immune system is an organism's protective mechanism against infectious environmental risk factors. It is also a driver of the pathogeneses of various human diseases, including cancer development and progression. Microalgae are increasingly being focused on as sources of bioactive molecules with therapeutic potential against various diseases. Furthermore, the antioxidant, anti-inflammatory, and anticancer potentials of microalgae and their secondary metabolites have been widely reported. However, the underlying mechanisms remain to be elucidated. Therefore, in this study, we investigated the molecular mechanisms underlying the anti-inflammatory and anticancer activities of the ethanol extract of the Antarctic freshwater microalga Micractinium sp. (ETMI) by several in vitro assays using RAW 264.7 macrophages and HCT116 human colon cancer cells. ETMI exerted its anti-inflammatory activity by modulating the main inflammatory indicators such as cyclooxygenase (COX)-2, interleukin (IL)-6, inducible nitric oxide synthase (iNOS), tumor necrosis factor (TNF)-α, and nitric oxide (NO) in a dose-dependent manner. In addition, ETMI exerted cytotoxic activity against HCT116 cells in a dose-dependent manner, leading to significantly reduced cancer cell proliferation. Further, it induced cell cycle arrest in the G1 phase through the regulation of hallmark genes of the G1/S phase transition, including CDKN1A, and cyclin-dependent kinase 4 and 6 (CDK4 and CDK6, respectively). At the transcriptional level, the expression of CDKN1A gradually increased in response to ETMI treatment while that of CDK4 and CDK6 decreased. Taken together, our findings suggest that the anti-inflammatory and anticancer activities of the Antarctic freshwater microalga, Micractinium sp., and ETMI may provide a new clue for understanding the molecular link between inflammation and cancer and that ETMI may be a potential anticancer agent for targeted therapy of colorectal cancer.


Assuntos
Antineoplásicos/farmacologia , Inflamação/tratamento farmacológico , Microalgas/química , Extratos Vegetais/farmacologia , Regiões Antárticas , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Ciclo-Oxigenase 2 , Etanol , Água Doce , Humanos , Lipopolissacarídeos , Macrófagos/efeitos dos fármacos , Óxido Nítrico , Óxido Nítrico Sintase Tipo II , Fator de Necrose Tumoral alfa
15.
Gynecol Oncol ; 145(2): 361-365, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28274569

RESUMO

OBJECTIVE: To test an electrically conductive chip, incorporating a nanoroughened microfluidic platform for the capture of circulating tumor cells (CTCs), and assess its clinical merit in instances of epithelial ovarian cancer (EOC). METHODS: A total of 54 patients with EOC recruited between August 2014 and May 2015 were enrolled in this prospective study. CTCs in peripheral blood were detected in advance of primary tumor resection and before initiating adjuvant chemotherapy for recurrent disease. We identified CTCs as EpCAM-positive and DAPI-positive, and CD45-negative feature. RESULTS: Twenty-four patients with primary disease and 30 patients with recurrences were included in the study. CTCs were detected in 98.1% (53/54). In newly diagnosed patients, median counts of single CTCs and CTC clusters were 4 (0-13) and 1(0-14), respectively. In those with recurrences, median counts were 3 (1-9) and 1(0-24), respectively. Such counts did not differ significantly by tumor stage or by serum CA125 level; but progression-free survival declined at a cutpoint of ≥3 CTCs, and CTC-cluster positivity correlated with platinum resistance. Isolated CTCs (successfully cultured ex vivo in two patients) showed greater sensitivity to anticancer drugs and proliferated more rapidly than did established cell lines. CONCLUSION: Proof-of-concept was provided for an electrically conductive and nanoroughened microfluidic platform-based chip designed to capture CTCs in patients with EOC. A larger patient sampling and longer duration of follow-up are needed to determine its suitability for clinical use.


Assuntos
Neoplasias Epiteliais e Glandulares/sangue , Neoplasias Epiteliais e Glandulares/patologia , Células Neoplásicas Circulantes/patologia , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/patologia , Carcinoma Epitelial do Ovário , Linhagem Celular Tumoral , Feminino , Humanos , Dispositivos Lab-On-A-Chip , Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias
16.
Prep Biochem Biotechnol ; 47(3): 299-304, 2017 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-27737617

RESUMO

To survive in a subzero environment, polar organisms produce ice-binding proteins (IBPs). These IBPs prevent the formation of large intracellular ice crystals, which may be fatal to the organism. Recently, a recombinant FfIBP (an IBP from Flavobacterium frigoris PS1) was cloned and produced in Pichia pastoris using fed-batch fermentation with methanol feeding. In this study, we demonstrate that FfIBP produced by P. pastoris has a glycosylation site, which diminishes the thermal hysteresis activity of FfIBP. The FfIBP expressed by P. pastoris exhibited a doublet on SDS-PAGE. The results of a glycosidase reaction suggested that FfIBP possesses complex N-linked oligosaccharides. These results indicate that the residues of the glycosylated site could disturb the binding of FfIBP to ice molecules. The findings of this study could be utilized to produce highly active antifreeze proteins on a large scale.


Assuntos
Proteínas Anticongelantes/genética , Proteínas Anticongelantes/metabolismo , Flavobacterium/genética , Gelo/análise , Pichia/genética , Sequência de Aminoácidos , Proteínas Anticongelantes/química , Clonagem Molecular , Fermentação , Flavobacterium/química , Flavobacterium/metabolismo , Glicosilação , Modelos Moleculares , Pichia/química , Pichia/metabolismo , Ligação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
17.
Prep Biochem Biotechnol ; 47(2): 143-150, 2017 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-27191514

RESUMO

Arctic Chlamydomonas sp. is a dominant microalgal strain in cold or frozen freshwater in the Arctic region. The full-length open reading frame of the omega-6 fatty acid desaturase gene (AChFAD6) was obtained from the transcriptomic database of Arctic Chlamydomonas sp. from the KOPRI culture collection of polar micro-organisms. Amino acid sequence analysis indicated the presence of three conserved histidine-rich segments as unique characteristics of omega-6 fatty acid desaturases, and three transmembrane regions transported to plastidic membranes by chloroplast transit peptides in the N-terminal region. The AChFAD6 desaturase activity was examined by expressing wild-type and V254A mutant (Mut-AChFAD6) heterologous recombinant proteins. Quantitative gas chromatography indicated that the concentration of linoleic acids in AChFAD6-transformed cells increased more than 3-fold [6.73 ± 0.13 mg g-1 dry cell weight (DCW)] compared with cells transformed with vector alone. In contrast, transformation with Mut-AChFAD6 increased the concentration of oleic acid to 9.23 ± 0.18 mg g-1 DCW, indicating a change in enzymatic activity to mimic that of stearoyl-CoA desaturase. These results demonstrate that AChFAD6 of Arctic Chlamydomonas sp. increases membrane fluidity by enhancing denaturation of C18 fatty acids and facilitates production of large quantities of linoleic fatty acids in prokaryotic expression systems.


Assuntos
Chlamydomonas/enzimologia , Ácidos Graxos Dessaturases/metabolismo , Mutação Puntual , Sequência de Aminoácidos , Regiões Árticas , Escherichia coli/genética , Ácidos Graxos Dessaturases/química , Ácidos Graxos Dessaturases/classificação , Ácidos Graxos Dessaturases/genética , Filogenia , Homologia de Sequência de Aminoácidos
18.
Bioprocess Biosyst Eng ; 39(1): 151-7, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26541584

RESUMO

Biodiesel produced from microalgae is a promising source of alternative energy. In winter, however, outdoor mass cultivation for biodiesel production is hampered by poor growth. Here, we report that Arctic Chlamydomonas sp. KNM0029C exhibits optimal growth at 4 °C and reaches densities up to 1.4 × 10(7) cells mL(-1). Lipid body formation in the alga was visualized through BODIPY 505/515 staining and fluorescence microscopy. The fatty acid methyl ester (FAME) production level of KNM0029C was 178.6 mg L(-1) culture and 2.3-fold higher than that of C. reinhardtii CC-125 at 4 °C. Analysis of the FAME content showed a predominance of polyunsaturated fatty acids such as C16:3, C18:2, C18:3, and C20:2. C18:3 fatty acids comprised the largest fraction (20.7%), and the content of polyunsaturated fatty acids (39.6%) was higher than that of saturated fatty acids (6.8%) at 4 °C. These results indicate that Chlamydomonas sp. KNM0029C, as a psychrophilic microalga, might represent a favorable source for biodiesel production in cold environments.


Assuntos
Biocombustíveis , Chlamydomonas/crescimento & desenvolvimento , Temperatura Baixa , Metabolismo dos Lipídeos/fisiologia , Lipídeos/biossíntese , Regiões Árticas
19.
J Cell Mol Med ; 19(2): 501-9, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25630974

RESUMO

The balanced turnover of collagen is necessary to maintain the mechanical strength of pelvic supportive connective tissues. Homeobox (HOX) A11 is a key transcriptional factor that controls collagen metabolism and homoeostasis in the uterosacral ligaments (USLs), and the deficient HOXA11 signalling may contribute to alterations in the biochemical strength of the USLs, leading to pelvic organ prolapse (POP). However, it is unknown how HOXA11 transcripts are regulated in the USLs. In this study, we found that microRNA (miRNA)-30d and 181a were overexpressed in women with POP, and their expression was inversely correlated with HOXA11 mRNA levels. The overexpression of miR-30d or 181a suppressed HOXA11 mRNA and protein levels in 293T cells, whereas the knockdown of these miRNAs enhanced HOXA11 levels and collagen production. Cotransfection of a luciferase reporter plasmid containing the 3'-untranslated region of HOXA11 with miR-30d or 181a mimic resulted in decreased relative luciferase activity. Conversely, cotransfection with anti-miR-30d or 181a increased luciferase activity. Taken together, these results indicate that both miR-30d and 181a are important posttranscriptional regulators of HOXA11 in the USLs and could be a potential therapeutic target for POP.


Assuntos
Proteínas de Homeodomínio/metabolismo , Ligamentos/metabolismo , MicroRNAs/metabolismo , Prolapso de Órgão Pélvico/metabolismo , Útero/metabolismo , Linhagem Celular , Tecido Conjuntivo/metabolismo , Feminino , Células HEK293 , Humanos , Pessoa de Meia-Idade
20.
J Urol ; 189(2): 588-94, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23260548

RESUMO

PURPOSE: Biomechanical weakness of the pelvic supportive structures has been proposed to be a cause of pelvic organ prolapse. However, the molecular mechanism involved in these changes is not completely understood. In this investigation we evaluated oxidative stress biomarkers in the uterosacral ligaments of women with pelvic organ prolapse and compared them with those of women with normal support. In addition, mitochondrial apoptosis was examined. MATERIALS AND METHODS: Samples were collected from 26 women with advanced stage pelvic organ prolapse and 29 age matched controls. The expression levels of 8-OHdG and 4-hydroxy-2-nonenal in the uterosacral ligaments were measured using immunohistochemistry. To assess mitochondrial apoptosis we performed TUNEL assay, immunohistochemistry for cleaved caspase-3 and cytochrome c, and Western blot analyses for cleaved caspase-3 and caspase-9. RESULTS: The mean percentage of cells immunopositive for 8-OHdG, 4-hydroxy-2-nonenal, TUNEL, cleaved caspase-3 and cytochrome c in the uterosacral ligaments was significantly higher in patients with pelvic organ prolapse than in controls. Similarly, Western blot analysis revealed increased expression of cleaved caspase-3 and caspase-9 in patients with pelvic organ prolapse. Correlation analyses revealed significant positive correlations between the percentage of cells immunopositive for 8-OHdG or 4-hydroxy-2-nonenal and markers of mitochondrial apoptosis. Analyzing by pelvic organ prolapse quantification system stage according to C point, the mean percentage of cells immunopositive for 8-OHdG, 4-hydroxy-2-nonenal and cytochrome c was significantly higher in patients with pelvic organ prolapse compared to controls, regardless of stage. However, the mean percentage of TUNEL and cleaved caspase-3 positive cells was significantly higher only in patients with stage III or IV pelvic organ prolapse. CONCLUSIONS: Oxidative stress and increased mitochondrial apoptosis may contribute to the pathological process of pelvic organ prolapse.


Assuntos
Apoptose/fisiologia , Mitocôndrias/fisiologia , Estresse Oxidativo , Prolapso de Órgão Pélvico/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
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