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1.
Clin Exp Immunol ; 208(1): 83-94, 2022 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-35274685

RESUMO

Macrophages are mediators of inflammation having an important role in the pathogenesis of cardiovascular diseases. Recently, a pro-inflammatory subpopulation, known as metabolically activated macrophages (MMe), has been described in conditions of obesity and metabolic syndrome where they are known to release cytokines that can promote insulin resistance. Dyslipidemia represents an important feature in metabolic syndrome and corresponds to one of the main modifiable risk factors for the development of cardiovascular diseases. Circulating monocytes can differentiate into macrophages under certain conditions. They correspond to a heterogeneous population, which include inflammatory and anti-inflammatory subsets; however, there is a wide spectrum of phenotypes. Therefore, we decided to investigate whether the metabolic activated monocyte (MoMe) subpopulation is already present under dyslipidemia conditions. Secondly, we assessed whether different levels of cholesterol and triglycerides play a role in the polarization towards the metabolic phenotype (MMe) of macrophages. Our results indicate that MoMe cells are found in both healthy and dyslipidemia patients, with cells displaying the following metabolic phenotype: CD14varCD36+ABCA1+PLIN2+. Furthermore, the percentages of CD14++CD68+CD80+ pro-inflammatory monocytes are higher in dyslipidemia than in healthy subjects. When analysing macrophage differentiation, we observed that MMe percentages were higher in the dyslipidemia group than in healthy subjects. These MMe have the ability to produce high levels of IL-6 and the anti-inflammatory cytokine IL-10. Furthermore, ABCA1 expression in MMe correlates with LDL serum levels. Our study highlights the dynamic contributions of metabolically activated macrophages in dyslipidemia, which may have a complex participation in low-grade inflammation due to their pro- and anti-inflammatory function.


Assuntos
Doenças Cardiovasculares , Síndrome Metabólica , Humanos , Monócitos/metabolismo , Doenças Cardiovasculares/patologia , Macrófagos/metabolismo , Inflamação/patologia , Fenótipo , Citocinas/metabolismo , Diferenciação Celular
2.
Front Plant Sci ; 11: 125, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32153620

RESUMO

Chromatin remodeling plays a key role in the establishment and maintenance of gene expression patterns essential for plant development and responses to environmental factors. Post-translational modification of histones, including acetylation, is one of the most relevant chromatin remodeling mechanisms that operate in eukaryotic cells. Histone acetylation is an evolutionarily conserved chromatin signature commonly associated with transcriptional activation. Histone acetylation levels are tightly regulated through the antagonistic activity of histone acetyltransferases (HATs) and histone deacetylases (HDACs). In plants, different families of HATs are present, including the MYST family, which comprises homologs of the catalytic subunit of the Nucleosome Acetyltransferase of H4 (NuA4) complex in yeast. This complex mediates acetylation of histones H4, H2A, and H2A.Z, and is involved in transcriptional regulation, heterochromatin silencing, cell cycle progression, and DNA repair in yeast. In Arabidopsis and, other plant species, homologs for most of the yeast NuA4 subunits are present and although the existence of this complex has not been demonstrated yet, compelling evidence supports the notion that this type of HAT complex functions from mosses to angiosperms. Recent proteomic studies show that several Arabidopsis homologs of NuA4 components, including the assembly platform proteins and the catalytic subunit, are associated in vivo with additional members of this complex suggesting that a NuA4-like HAT complex is present in plants. Furthermore, the functional characterization of some Arabidopsis NuA4 subunits has uncovered the involvement of these proteins in the regulation of different plant biological processes. Interestingly, for most of the mutant plants deficient in subunits of this complex characterized so far, conspicuous defects in flowering time are observed, suggesting a role for NuA4 in the control of this plant developmental program. Moreover, the participation of Arabidopsis NuA4 homologs in other developmental processes, such as gametophyte development, as well as in cell proliferation and stress and hormone responses, has also been reported. In this review, we summarize the current state of knowledge on plant putative NuA4 subunits and discuss the latest progress concerning the function of this chromatin modifying complex.

3.
PLoS One ; 13(2): e0192618, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29447216

RESUMO

Endophytic bacteria are wide-spread and associated with plant physiological benefits, yet their genomes and secondary metabolites remain largely unidentified. In this study, we explored the genome of the endophyte Streptomyces scabrisporus NF3 for discovery of potential novel molecules as well as genes and metabolites involved in host interactions. The complete genomes of seven Streptomyces and three other more distantly related bacteria were used to define the functional landscape of this unique microbe. The S. scabrisporus NF3 genome is larger than the average Streptomyces genome and not structured for an obligate endosymbiotic lifestyle; this and the fact that can grow in R2YE media implies that it could include a soil-living stage. The genome displays an enrichment of genes associated with amino acid production, protein secretion, secondary metabolite and antioxidants production and xenobiotic degradation, indicating that S. scabrisporus NF3 could contribute to the metabolic enrichment of soil microbial communities and of its hosts. Importantly, besides its metabolic advantages, the genome showed evidence for differential functional specificity and diversification of plant interaction molecules, including genes for the production of plant hormones, stress resistance molecules, chitinases, antibiotics and siderophores. Given the diversity of S. scabrisporus mechanisms for host upkeep, we propose that these strategies were necessary for its adaptation to plant hosts and to face changes in environmental conditions.


Assuntos
Genoma Bacteriano , Plantas/microbiologia , Streptomyces/genética , Simbiose
4.
Pharm Biol ; 54(9): 1822-30, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26731099

RESUMO

Context Hamelia patens Jacq. (Rubiaceae) is traditionally used to treat wounds, inflammation and diabetes. However, there is still a lack of scientific evidence to support these applications. Objective The objective of this study is to evaluate the anti-inflammatory, antioxidant and antidiabetic activities of Hamelia patens, and identify its bioactive compounds. Materials and methods Four extracts were obtained by maceration and liquid-liquid extraction: HEX, DCM-EtOAc, MeOH-EtOAc and MeOH-Aq. The anti-inflammatory effect was evaluated orally on rat paw carrageenan-induced oedema over 6 h (50, 200 and 500 mg/kg), and topically in mouse ear oedema induced by 12-tetradecanoylphorbol-13-acetate (TPA) after 4 h (0.5 and 1 mg/ear). We also evaluated myeloperoxidase levels in ear tissue, 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging ability, and in vitro α-glucosidase inhibition. The chemical compounds were separated by column chromatography and identified by spectroscopic analysis. Results We found that the oral administration of the HEX extract at 500 and 200 mg/kg significantly decreased the carrageenan-induced inflammation after 1 and 3 h, respectively. The MeOH-EtOAc extract significantly inhibited myeloperoxidase activity (83.5%), followed by the DCM-EtOAc extract (76%), ß-sitosterol/stigmasterol (72.7%) and the HEX extract (55%), which significantly decreased oedema induced by TPA at both doses, giving a similar effect to indomethacin. We also found that the MeOH-EtOAc, MeOH-Aq and DCM-EtOAc extracts showed good DPPH scavenging activity (IC50 values of 18.6, 93.9 and 158.2 µg/mL, respectively). The HEX extract showed the lowest α-glucosidase inhibition (an IC50 value of 26.07 µg/mL), followed by the MeOH-EtOAc extract (an IC50 value of 30.18 µg/mL), ß-sitosterol/stigmasterol (IC50 34.6 µg/mL) and compound A ((6E,10E,14E,18E)-2,6,10,14,18,23-hexamethyl-2,6,10,14,18,22-tetracosahexaene, an IC50 value of 114.6 µg/mL), which were isolated for the first time from Hamelia patens. Discussion and conclusion Hamelia patens possesses anti-inflammatory, antioxidant and α-glucosidase inhibitory activities, which support its traditional use. These effects can be attributed to the identified compounds.


Assuntos
Anti-Inflamatórios/farmacologia , Edema/prevenção & controle , Sequestradores de Radicais Livres/farmacologia , Inibidores de Glicosídeo Hidrolases/farmacologia , Hamelia , Animais , Anti-Inflamatórios/isolamento & purificação , Compostos de Bifenilo/química , Carragenina , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Edema/metabolismo , Feminino , Sequestradores de Radicais Livres/isolamento & purificação , Inibidores de Glicosídeo Hidrolases/isolamento & purificação , Hamelia/química , Peroxidase/metabolismo , Fitoterapia , Picratos/química , Folhas de Planta , Plantas Medicinais , Ratos Wistar , Proteínas de Saccharomyces cerevisiae/antagonistas & inibidores , Proteínas de Saccharomyces cerevisiae/metabolismo , Solventes/química , Acetato de Tetradecanoilforbol , Fatores de Tempo , alfa-Glucosidases/metabolismo
5.
Exp Toxicol Pathol ; 64(1-2): 25-30, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20580540

RESUMO

UNLABELLED: The (As) arsenic exposure is a risk factor for causing disturbances in the endocrine organs. OBJECTIVE: To evaluate if sub-chronic As exposure during the pre- and postnatal development causes disturbances in the puberty. Moreover, determine adverse effects of As on the ovarian follicle and adrenocortical cell maturation. METHODS: Females adult Wistar rats were exposed to sodium arsenite at 3 ppm calculated as As in drinking water from mating, gestation. Following the birth, the female offspring continued exposured to As via lactation. Weaned pups received the same As treatment as mothers, until they were 1-4 months (mo) old. At these ages, blood sampling and tissue harvest were done. The tissues were fixed in situ with 4% paraformaldehyde in phosphate buffer. After the perfusion the ovaries, uterus, adrenal glands were harvested, dissected out, weighted. The ovaries and the adrenal glands were processed to paraffin and sectioned at 5 µM and stained with hematoxylin and eosin for light microscopy. STATISTICAL ANALYSIS: Comparisons between groups were made by unpaired t-test or nonparametric Mann-Whitney test as appropriate. RESULTS: 100% As treated rats at 1 mo of age were at diestrous stage, with low estradiol E2. As treatment caused disturbances in the morphology of the ovarian cell consisting in DNA damage evidenced by picknotic chromatin, cariorexis, significant cytoplasmic vacuolization and also vasculature damaged. Arrest in follicle maturation was also present. CONCLUSIONS: We found that the onset of puberty in the As treated rats was 1 mo delayed since vagina was still closed, the vaginal smear showed that they were at diestrus stage with plasma low E2 levels.


Assuntos
Envelhecimento/efeitos dos fármacos , Arsenitos/toxicidade , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Maturidade Sexual/efeitos dos fármacos , Compostos de Sódio/toxicidade , Córtex Suprarrenal/efeitos dos fármacos , Córtex Suprarrenal/embriologia , Córtex Suprarrenal/crescimento & desenvolvimento , Envelhecimento/sangue , Animais , Arsenitos/farmacocinética , Estradiol/sangue , Ciclo Estral/sangue , Ciclo Estral/efeitos dos fármacos , Feminino , Lactação , Masculino , Gravidez , Efeitos Tardios da Exposição Pré-Natal/sangue , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Progesterona/sangue , Ratos , Ratos Wistar , Compostos de Sódio/farmacocinética , Vagina/efeitos dos fármacos , Vagina/embriologia , Vagina/crescimento & desenvolvimento
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