RESUMO
Long interspersed nuclear elements-1 (LINE-1) are mobile DNA elements that comprise the majority of interspersed repeats in the mammalian genome. During the last decade, these transposable sequences have been described as controlling elements involved in transcriptional regulation and genome plasticity. Recently, LINE-1 have been implicated in neurogenesis, but to date little is known about their nuclear organization in neurons. The olfactory epithelium is a site of continuous neurogenesis, and loci of olfactory receptor genes are enriched in LINE-1 copies. Olfactory neurons have a unique inverted nuclear architecture and constitutive heterochromatin forms a block in the center of the nuclei. Our DNA FISH images show that, even though LINE-1 copies are dispersed throughout the mice genome, they are clustered forming a cap around the central heterochromatin block and frequently occupy the same position as facultative heterochromatin in olfactory neurons nuclei. This specific LINE-1 organization could not be observed in other olfactory epithelium cell types. Analyses of H3K27me3 and H3K9me3 ChIP-seq data from olfactory epithelium revealed that LINE-1 copies located at OR gene loci show different enrichment for these heterochromatin marks. We also found that LINE-1 are transcribed in mouse olfactory epithelium. These results suggest that LINE-1 play a role in the olfactory neurons' nuclear architecture. SIGNIFICANCE STATEMENT: LINE-1 are mobile DNA elements and comprise almost 20% of mice and human genomes. These retrotransposons have been implicated in neurogenesis. We show for the first time that LINE-1 retrotransposons have a specific nuclear organization in olfactory neurons, forming aggregates concentric to the heterochromatin block and frequently occupying the same region as facultative heterochromatin. We found that LINE-1 at olfactory receptor gene loci are differently enriched for H3K9me3 and H3K27me3, but LINE-1 transcripts could be detected in the olfactory epithelium. We speculate that these retrotransposons play an active role in olfactory neurons' nuclear architecture.
Assuntos
Elementos Nucleotídeos Longos e Dispersos/fisiologia , Mucosa Olfatória/metabolismo , Neurônios Receptores Olfatórios/metabolismo , Receptores Odorantes/metabolismo , Animais , Núcleo Celular/metabolismo , Regulação da Expressão Gênica/fisiologia , Heterocromatina/metabolismo , Histonas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Receptores Odorantes/genéticaRESUMO
We previously published on the design and synthesis of novel, potent and selective PPARα antagonists suitable for either i.p. or oral in vivo administration for the potential treatment of cancer. Described herein is SAR for a subsequent program, where we set out to identify selective and potent PPARα/δ dual antagonist molecules. Emerging literature indicates that both PPARα and PPARδ antagonism may be helpful in curbing the proliferation of certain types of cancer. This dual antagonism could also be used to study PPARs in other settings. After testing for selective and dual potency, off-target counter screening, metabolic stability, oral bioavailability and associated toxicity, compound 11, the first reported PPARα/δ dual antagonist was chosen for more advanced preclinical evaluation.
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Antineoplásicos/farmacologia , Descoberta de Drogas , Neoplasias Ovarianas/tratamento farmacológico , PPAR alfa/antagonistas & inibidores , PPAR delta/antagonistas & inibidores , Sulfonamidas/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cães , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Camundongos , Estrutura Molecular , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , PPAR alfa/metabolismo , PPAR delta/metabolismo , Ratos , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/químicaRESUMO
Females exhibit more robust Th1 responses than males. Our previous work suggested that this sex disparity is a consequence of higher activity of the androgen-induced gene peroxisome proliferator-activated receptor α (PPARα) in male CD4(+) T cells. The objective of this study was to elucidate the cellular and molecular mechanism of how PPARα inhibits Th1 responses in male mice. In this study, we found that PPARα functions within CD4(+) and CD8(+) T lymphocytes and NKT cells to negatively regulate IFN-γ responses in male mice and identified Ifng as the gene target of PPARα repression. Treatment of male CD4(+) T cells with the PPARα agonist fenofibrate induced the recruitment of PPARα and the nuclear receptor-interacting protein, nuclear receptor corepressor 1, to specific cis-regulatory elements in the Ifng locus. This recruitment associated with reduced histone acetylation at these sites. Knockdown of nuclear receptor corepressor 1 in primary male T cells abolished the effect of fenofibrate in reducing IFN-γ production. In contrast, treatment of male T cells with IS001, a novel antagonist of PPARα, increased Ifng gene expression and histone acetylation across the Ifng locus. Finally, we investigated the effects of IS001 on IFN-γ responses in mice during infection with the Th1-associated pathogen Listeria monocytogenes and observed that IS001 enhanced IFN-γ production by NKT, CD4(+), and CD8(+) T cells and improved the survival of male, but not female, mice. Our findings provide a novel mechanism of why IFN-γ responses are more robust in females and introduce a small-molecule IS001 that can be used to enhance Th1 immunity in males.
Assuntos
Linfócitos T CD8-Positivos/imunologia , Interferon gama/imunologia , Células T Matadoras Naturais/imunologia , PPAR alfa/fisiologia , Células Th1/imunologia , Acetilação , Acrilamidas/farmacologia , Animais , Fenofibrato/farmacologia , Histonas/metabolismo , Interferon gama/biossíntese , Listeria monocytogenes/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Correpressor 1 de Receptor Nuclear/genética , Correpressor 1 de Receptor Nuclear/metabolismo , PPAR alfa/antagonistas & inibidores , PPAR alfa/genética , Compostos de Piridínio/farmacologia , Interferência de RNA , RNA Interferente Pequeno/genética , Fatores SexuaisRESUMO
Odorants are detected by odorant receptors, which are located on olfactory sensory neurons of the nose. Each olfactory sensory neuron expresses one single odorant receptor gene allele from a large family of odorant receptor genes. To gain insight into the mechanisms underlying this monogenic and monoallelic expression, we examined the 3D nuclear organization of olfactory sensory neurons and determined the positions of homologous odorant receptor gene alleles in relation to different nuclear compartments. Our results show that olfactory neurons exhibit a singular nuclear architecture that is characterized by a large centrally localized constitutive heterochromatin block and by the presence of prominent facultative heterochromatin domains that are localized around this constitutive heterochromatin block. We also found that the two homologous alleles of a given odorant receptor gene are frequently segregated to separate compartments in the nucleus, with one of the alleles localized to the constitutive heterochromatin block and the other one localized to the more plastic facultative heterochromatin, or next to it. Our findings suggest that this nuclear compartmentalization may play a critical role in the expression of odorant receptor genes.
Assuntos
Alelos , Núcleo Celular/ultraestrutura , Regulação da Expressão Gênica/genética , Heterocromatina/metabolismo , Neurônios Receptores Olfatórios/citologia , Receptores Odorantes/genética , Animais , Núcleo Celular/genética , Cromossomos Artificiais Bacterianos , Imageamento Tridimensional , Hibridização in Situ Fluorescente , CamundongosRESUMO
Odorant receptors (ORs) belong to a large gene family of rhodopsin-like G protein-coupled receptors (GPCRs). The mouse OR gene family is composed of â¼1000 OR genes, and the human OR gene family is composed of â¼400 OR genes. The OR genes are spread throughout the genome, and can be found in clusters or as solitary genes in almost all chromosomes. These chemosensory GPCRs are expressed in highly specialized cells, the olfactory sensory neurons of the nose. Each one of these neurons expresses a single OR gene out of the complete repertoire of genes. In addition, only one of the two homologous alleles of the chosen OR gene, the maternal or the paternal, is expressed per neuron. Here we review recent findings that help to elucidate the mechanisms underlying monogenic and monoallelic expression of OR genes.
Assuntos
Alelos , Regulação da Expressão Gênica , Receptores Odorantes/genética , Animais , Humanos , Modelos Genéticos , Receptores Odorantes/metabolismoRESUMO
Tumor-specific metabolic changes can reveal new therapeutic targets. Our findings implicate a supporting role for fatty acid metabolism in chronic lymphocytic leukemia (CLL) cell survival. Peroxisome proliferator-activated receptor (PPAR)-α, a major transcriptional regulator of fatty acid oxidation, was recently shown to be upregulated in CLL. To evaluate PPARα as a potential therapeutic target, we developed a highly selective, potent small molecule antagonist of PPARα, NXT629. NXT629 inhibited agonist-induced transcription of PPARα-regulated genes, demonstrating target engagement in CLL cells. Furthermore, NXT629 induced apoptosis of CLL cells even in the presence of a protective microenvironment. To mimic the proliferative lymphoid compartment of CLL, we examined the activity of NXT629 on CLL cells that were stimulated to proliferate in vitro. NXT629 reduced the number of leukemia cells undergoing cell division. In addition, in two xenograft mouse models of CLL (one a model for nondividing and one for dividing CLL), NXT629 reduced the number of viable CLL cells in vivo. Overall, these results suggest that fatty acid metabolism promotes survival and proliferation of primary CLL cells and that inhibiting PPARα gene regulation could be a new therapeutic approach to treating CLL.
Assuntos
Aminopiridinas/administração & dosagem , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , PPAR alfa/genética , Sulfonamidas/administração & dosagem , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ácidos Graxos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Leucemia Linfocítica Crônica de Células B/genética , Leucemia Linfocítica Crônica de Células B/patologia , Camundongos , PPAR alfa/antagonistas & inibidores , Ativação TranscricionalRESUMO
The discovery and SAR of a novel series of potent and selective PPARα antagonists are herein described. Exploration of replacements for the labile acyl sulfonamide linker led to a biaryl sulfonamide series of which compound 33 proved to be suitable for further profiling in vivo. Compound 33 demonstrated excellent potency, selectivity against other nuclear hormone receptors, and good pharmacokinetics in mouse.
Assuntos
PPAR alfa/antagonistas & inibidores , Sulfonamidas/química , Sulfonamidas/farmacologia , Animais , Butiratos/química , Butiratos/farmacologia , Humanos , Camundongos , Estrutura Molecular , Oxazóis/química , Oxazóis/farmacologia , Compostos de Fenilureia/química , Compostos de Fenilureia/farmacologia , Propionatos/química , Propionatos/farmacologia , Relação Estrutura-Atividade , Triazóis/química , Triazóis/farmacologia , Tirosina/análogos & derivados , Tirosina/química , Tirosina/farmacologiaRESUMO
This study investigated the effects of fish oil (FO) treatment, particularly enriched with eicosapentaenoic acid (EPA), on obesity induced by a high-fat diet (HFD) in mice. The investigation focused on elucidating the impact of FO on epigenetic modifications in white adipose tissue (WAT) and the involvement of adipose-derived stem cells (ASCs). C57BL/6j mice were divided into two groups: control diet and HFD for 16 weeks. In the last 8 weeks, the HFD group was subdivided into HFD and HFD + FO (treated with FO). WAT was removed for RNA and protein extraction, while ASCs were isolated, cultured, and treated with leptin. All samples were analyzed using functional genomics tools, including PCR-array, RT-PCR, and Western Blot assays. Mice receiving an HFD displayed increased body mass, fat accumulation, and altered gene expression associated with WAT inflammation and dysfunction. FO supplementation attenuated these effects, a potential protective role against HFD-induced obesity. Analysis of H3K27 revealed HFD-induced changes in histone, which were partially reversed by FO treatment. This study further explored leptin signaling in ASCs, suggesting a potential mechanism for ASC dysfunction in the obesity-rich leptin environment of WAT. Overall, FO supplementation demonstrated efficacy in mitigating HFD-induced obesity, influencing epigenetic and molecular pathways, and shedding light on the role of ASCs and leptin signaling in WAT dysfunction associated with obesity.
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Purpose: This study explores the impact of gestational diabetes mellitus (GDM) subtypes classified by oral glucose tolerance test (OGTT) values on maternal and perinatal outcomes. Patients and Methods: This multicenter prospective cohort study (May 2019-December 2022) included participants from the Mexican multicenter cohort study Cuido mi Embarazo (CME). Women were classified into four groups per 75-g 2-h OGTT: 1) normal glucose tolerance (normal OGTT), 2) GDM-Sensitivity (isolated abnormal fasting or abnormal fasting in combination with 1-h or 2-h abnormal results), 3) GDM-Secretion (isolated abnormal values at 1-h or 2-h or their combination), and 4) GDM-Mixed (three abnormal values). Cesarean delivery, neonates large for gestational age (LGA), and pre-term birth rates were among the outcomes compared. Between-group comparisons were analyzed using either the t-test, chi-square test, or Fisher's exact test. Results: Of 2,056 Mexican pregnant women in the CME cohort, 294 (14.3%) had GDM; 53.7%, 34.4%, and 11.9% were classified as GDM-Sensitivity, GDM-Secretion, and GDM-Mixed subtypes, respectively. Women with GDM were older (p = 0.0001) and more often multiparous (p = 0.119) vs without GDM. Cesarean delivery (63.3%; p = 0.02) and neonate LGA (10.7%; p = 0.078) were higher in the GDM-Mixed group than the overall GDM group (55.6% and 8.4%, respectively). Pre-term birth was more common in the GDM-Sensitivity group than in the overall GDM group (10.2% vs 8.5%, respectively; p=0.022). At 6 months postpartum, prediabetes was more frequent in the GDM-Sensitivity group than in the overall GDM group (31.6% vs 25.5%). Type 2 diabetes was more common in the GDM-Mixed group than in the overall GDM group (10.0% vs 3.3%). Conclusion: GDM subtypes effectively stratified maternal and perinatal risks. GDM-Mixed subtype increased the risk of cesarean delivery, LGA, and type 2 diabetes postpartum. GDM subtypes may help personalize clinical interventions and optimize maternal and perinatal outcomes.
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BACKGROUND: Patients with balanced X-autosome translocations and premature ovarian insufficiency (POI) constitute an interesting paradigm to study the effect of chromosome repositioning. Their breakpoints are clustered within cytobands Xq13-Xq21, 80% of them in Xq21, and usually, no gene disruption can be associated with POI phenotype. As deletions within Xq21 do not cause POI, and since different breakpoints and translocations with different autosomes lead to this same gonadal phenotype, a "position effect" is hypothesized as a possible mechanism underlying POI pathogenesis. OBJECTIVE AND METHODS: To study the effect of the balanced X-autosome translocations that result in POI, we fine-mapped the breakpoints in six patients with POI and balanced X-autosome translocations and addressed gene expression and chromatin accessibility changes in four of them. RESULTS: We observed differential expression in 85 coding genes, associated with protein regulation, multicellular regulation, integrin signaling, and immune response pathways, and 120 differential peaks for the three interrogated histone marks, most of which were mapped in high-activity chromatin state regions. The integrative analysis between transcriptome and chromatin data pointed to 12 peaks mapped less than 2 Mb from 11 differentially expressed genes in genomic regions not related to the patients' chromosomal rearrangement, suggesting that translocations have broad effects on the chromatin structure. CONCLUSION: Since a wide impact on gene regulation was observed in patients, our results observed in this study support the hypothesis of position effect as a pathogenic mechanism for premature ovarian insufficiency associated with X-autosome translocations. This work emphasizes the relevance of chromatin changes in structural variation, since it advances our knowledge of the impact of perturbations in the regulatory landscape within interphase nuclei, resulting in the position effect pathogenicity.
Assuntos
Insuficiência Ovariana Primária , Feminino , Humanos , Insuficiência Ovariana Primária/genética , Translocação Genética , Regulação da Expressão Gênica , Expressão Gênica , CromatinaRESUMO
Given the barriers to early detection of gestational diabetes mellitus (GDM), this study aimed to develop an artificial intelligence (AI)-based prediction model for GDM in pregnant Mexican women. Data were retrieved from 1709 pregnant women who participated in the multicenter prospective cohort study 'Cuido mi embarazo'. A machine-learning-driven method was used to select the best predictive variables for GDM risk: age, family history of type 2 diabetes, previous diagnosis of hypertension, pregestational body mass index, gestational week, parity, birth weight of last child, and random capillary glucose. An artificial neural network approach was then used to build the model, which achieved a high level of accuracy (70.3%) and sensitivity (83.3%) for identifying women at high risk of developing GDM. This AI-based model will be applied throughout Mexico to improve the timing and quality of GDM interventions. Given the ease of obtaining the model variables, this model is expected to be clinically strategic, allowing prioritization of preventative treatment and promising a paradigm shift in prevention and primary healthcare during pregnancy. This AI model uses variables that are easily collected to identify pregnant women at risk of developing GDM with a high level of accuracy and precision.
Assuntos
Diabetes Mellitus Tipo 2 , Diabetes Gestacional , Criança , Gravidez , Feminino , Humanos , Recém-Nascido , Diabetes Gestacional/diagnóstico , Estudos Prospectivos , Inteligência Artificial , México/epidemiologia , Fatores de RiscoRESUMO
Adipose tissue (AT) secretes adipokines, modulators of low-grade chronic inflammation in obesity. Molecules that induce the emergence of new and functional adipocytes in AT can alleviate or prevent inflammatory and metabolic disorders. The objective of this study was to investigate the role of palmitoleic acid (n7) in 3T3-L1 and primary pre-adipocyte differentiation and AT inflammation. C57BL/6j mice were submitted to a control or high-fat diet (HFD) for 8 weeks, and treated with n7 for 4 weeks. Mice consuming a HFD presented an increase in body weight, epididymal (Epi) fat mass, and Epi adipocytes size. N7 treatment attenuated the body weight gain and completely prevented the hypertrophy of Epi adipocytes, but not the increment in Epi mass induced by the HFD, suggesting a greater adipocytes hyperplasia in animals treated with n7. It was agreed that n7 increased 3T3-L1 proliferation and differentiation, as well as the expression of genes involved in adipogenesis, such as Cebpa, Pparg, aP2, Perilipin, and Scl2a4. Furthermore, n7 decreased the inflammatory cytokines Mcp1, Tnfa, Il6, Cxcl10, and Nos2 genes in Epi vascular stromal cells, but not in the whole AT. These findings show that n7 exerts anti-hypertrophic effects in adipocytes which influence the surrounding cells by attenuating the overexpression of pro-inflammatory cytokines triggered by a HFD.
RESUMO
OBJECTIVE: The study goal was to analyze the effects of a high-fat diet (HFD) on the histone 3 lysine 27 (H3K27) posttranscriptional modifications and the expression of histone-modifying enzymes in adipose-derived stromal cells (ASCs) from white adipose tissue (WAT). METHODS: Male C57BL/6J mice received control or HFD for 12 weeks. The ASCs were isolated from subcutaneous and visceral (epididymal) WAT, cultivated, and evaluated for expression of H3K27 trimethylation (H3K27me3) and H3K27 acetylation (H3K27ac) by Western blot. The transcription of histone-modifying enzymes was analyzed by real-time polymerase chain reaction. RESULTS: When compared with control, HFD ASCs showed a decrease in H3K27ac enrichment in subcutaneous and visceral WAT and ATP-citrate lyase expression in subcutaneous WAT. Curiously, the expression of CREB-binding protein was increased in visceral ASCs from HFD-fed mice. CONCLUSIONS: These results show that an HFD significantly reduces acetylation of H3K27 in ASCs and the expression of ATP-citrate lyase in subcutaneous ASCs, suggesting that, in this fat depot, the H3K27ac reduction could be partly due to lower acetyl-coenzyme A availability. H3K27ac is an epigenetic mark responsible for increasing the transcription rate and its reduction can have an important impact on ASC proliferation and differentiation potential.
Assuntos
Dieta Hiperlipídica , Histonas , Acetilação , Trifosfato de Adenosina , Animais , Proteína de Ligação a CREB/metabolismo , Coenzima A/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células Estromais/metabolismoRESUMO
Purpose: Few pregnant women in low-resource settings are screened for gestational diabetes mellitus (GDM) using the gold standard oral glucose tolerance test (OGTT). This study compared capillary blood glucose testing with 2-h plasma glucose measurements obtained using the 75-g OGTT to screen for GDM at primary healthcare clinics in Mexico. Patients and Methods: Pregnant women who participated in a previous prospective multicenter longitudinal cohort study and who had not been previously diagnosed with diabetes were included. Participants were evaluated using the plasmatic 2-h 75-g OGTT with simultaneous capillary blood glucose measurements using a glucometer. The study endpoint was the comparability of the glucometer results to the gold standard OGTT when collected simultaneously. Sensitivity, specificity, and area under the curve of the glucose measurements obtained for capillary blood compared with venous plasma (gold standard) were calculated to determine diagnostic accuracy. Results: The study included 947 pregnant women who had simultaneous glucose measurements available (blood capillary [glucometer] and venous blood OGTT). Overall, capillary blood glucose testing was very sensitive (89.47%); the specificity was 66.58% and the area under the curve (95% confidence interval) was 0.78 (0.74-0.81). The sensitivity, specificity and area under the curve of each capillary measurement were: 89.47%, 66.58% and 0.78 (0.74-0.82) for the fasting measurement, 91.53%, 93.24% and 0.92 (0.88-0.96) for the one-hour measurement, and 89.80%, 93.32%, 0.91 (0.87-0.95) for the second-hour measurement, respectively. No adverse events were reported. Conclusion: Capillary OGTT is a valid alternative to the gold standard OGTT for screening of GDM in low-resource situations or in situations where there are other limitations to performing the OGTT as part of primary healthcare services.
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Compound 21 (AM432) was identified as a potent and selective antagonist of the DP(2) receptor (CRTH2). Modification of a bi-aryl core identified a series of tri-aryl antagonists of which compound 21 proved a viable clinical candidate. AM432 shows excellent potency in a human whole blood eosinophil shape change assay with prolonged incubation, a comparatively long off-rate from the DP(2) receptor, excellent pharmacokinetics in dog and in vivo activity in two mouse models of inflammatory disease after oral dosing.
Assuntos
Fenilacetatos/química , Piridinas/química , Receptores Imunológicos/antagonistas & inibidores , Receptores de Prostaglandina/antagonistas & inibidores , Administração Oral , Animais , Modelos Animais de Doenças , Cães , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia , Humanos , Inflamação/tratamento farmacológico , Camundongos , Fenilacetatos/farmacocinética , Fenilacetatos/uso terapêutico , Piridinas/farmacocinética , Piridinas/uso terapêutico , Receptores Imunológicos/metabolismo , Receptores de Prostaglandina/metabolismoRESUMO
This study aimed to investigate the effects of two commercially available fish oils (FOs) containing different proportions of two omega-3 fatty acids (FA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), on the metabolic and endocrine dysfunctions of white adipose tissue resulting from obesity. Male C57BL/6J mice, 8 weeks old, received a control or high-fat diet (CO and HF groups, with 9% and 59% energy from fat, respectively) for 8 weeks. The next 8 weeks, the HF group was subdivided into HF, HF+FO/E (HF+5:1 EPA:DHA), and HF+FO/D (HF+5:1 DHA:EPA). Supplementation was performed by gavage, three times a week. All groups that received the HF diet had lower food and caloric intake, but a higher fat intake, body weight (BW) gain, glucose intolerance, and a significant increase in inguinal (ING), retroperitoneal (RP), and epididymal (EPI) adipose tissues when compared to the CO group. Additionally, HF and HF+FO/D groups showed insulin resistance, adipocyte hypertrophy, increased lipolysis and secretion of TNF-α, resistin and IL-10 adipokines by ING and RP adipocytes, and adiponectin only by the HF+FO/D group in ING adipocytes. All of these effects were completely reversed in the HF+FO/E group, which also showed partial reversion in BW gain and glucose intolerance. Both the HF+FO/E and HF+FO/D groups showed a reduction in ING and RP adipose depots when compared to the HF group, but only HF+FO/E in the EPI depot. HF+FO/E, but not HF+FO/D, was able to prevent the changes triggered by obesity in TNF-α, Il-10, and resistin secretion in ING and RP depots. These results strongly suggest that different EPA:DHA ratios have different impacts on the adipose tissue metabolism, FO being rich in EPA, but not in DHA, and effective in reversing the changes induced by obesity.
Assuntos
Ácido Eicosapentaenoico/farmacologia , Óleos de Peixe/farmacologia , Alimentos Fortificados , Síndrome Metabólica/terapia , Obesidade/terapia , Adipócitos/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Ácidos Docosa-Hexaenoicos/farmacologia , Resistência à Insulina/fisiologia , Masculino , Síndrome Metabólica/complicações , Síndrome Metabólica/fisiopatologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Obesidade/complicações , Obesidade/fisiopatologia , Aumento de Peso/efeitos dos fármacosRESUMO
The increasing impact of obesity on global human health intensifies the importance of studies focusing on agents interfering with the metabolism and remodeling not only of the white adipose tissue (WAT) but also of the liver. In the present study, we have addressed the impact of n-3 PUFA in adipose cells' proliferation and adipogenesis, as well as in the hepatic lipid profile and morphology. Mice were induced to obesity by the consumption of a high-fat diet (HFD) for 16 weeks. At the 9th week, the treatment with fish oil (FO) was initiated and maintained until the end of the period. The FO treatment reduced the animals' body mass, plasma lipids, glucose, plasma transaminases, liver mass, triacylglycerol, and cholesterol liver content when compared to animals consuming only HFD. FO also decreased the inguinal (ing) WAT mass, reduced adipocyte volume, increased adipose cellularity (hyperplasia), and increased the proliferation of adipose-derived stromal cells (AdSCs) which corroborates the increment in the proliferation of 3T3-L1 pre-adipocytes or AdSCs treated in vitro with n-3 PUFA. After submitting the in vitro treated (n-3 PUFA) cells, 3T3-L1 and AdSCs, to an adipogenic cocktail, there was an increase in the mRNA expression of adipogenic transcriptional factors and other late adipocyte markers, as well as an increase in lipid accumulation when compared to not treated cells. Finally, the expression of browning-related genes was also higher in the n-3 PUFA treated group. We conclude that n-3 PUFA exerts an attenuating effect on body mass, dyslipidemia, and hepatic steatosis induced by HFD. FO treatment led to decreasing adiposity and adipocyte hypertrophy in ingWAT while increasing hyperplasia. Data suggest that FO treatment might induce recruitment (by increased proliferation and differentiation) of new adipocytes (white and/or beige) to the ingWAT, which is fundamental for the healthy expansion of WAT.
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Adipogenia/efeitos dos fármacos , Ácidos Graxos Ômega-3/farmacologia , Óleos de Peixe/farmacologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Obesidade/terapia , Células 3T3-L1 , Adipócitos/efeitos dos fármacos , Tecido Adiposo Branco/efeitos dos fármacos , Adiposidade/efeitos dos fármacos , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Dieta Hiperlipídica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Obesidade/complicaçõesRESUMO
AM643 (compound 6, 3-{3-tert-butylsulfanyl-1-[4-(5-methoxy-pyrimidin-2-yl)-benzyl]-5-(5-methyl-pyridin-2-ylmethoxy)-1H-indol-2-yl]-2,2-dimethyl-propionic acid) was identified as a potential candidate for formulation as a topical agent for the treatment of skin disorders involving leukotriene production. Dermal application of 6 using a prototypical vehicle in a murine ear arachidonic acid model showed significant reduction in the concentrations of leukotrienes in mouse skin with concomitant reduction in ear swelling.
Assuntos
Inibidores Enzimáticos/química , Indóis/síntese química , Propionatos/síntese química , Proteínas Ativadoras de 5-Lipoxigenase/metabolismo , Administração Tópica , Animais , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/uso terapêutico , Humanos , Indóis/química , Indóis/uso terapêutico , Leucotrienos/biossíntese , Camundongos , Propionatos/química , Propionatos/uso terapêutico , Ratos , Dermatopatias/induzido quimicamente , Dermatopatias/tratamento farmacológicoRESUMO
We recently demonstrated that palmitoleic acid (C16:1n7), a monounsaturated fatty acid, increases the metabolic and oxidative capacity of 3T3-L1 adipocytes. Herein, the effect of 16:1n7 supplementation on metabolic parameters on white adipose tissue (WAT) and liver of obese mice induced by a high-fat diet (HFD) was addressed by analyzing metabolic (dys)function and altered genes expression in adipose tissue, as well as liver and serum biochemistry analysis. For this purpose, mice were induced to obesity for 8 weeks, and from the 5th week, they received 16:1n7 (300 mg/kg per day) or water for 30 days, by gavage. Subcutaneous inguinal (ING) and epididymal (EPI) WAT were removed for analysis of metabolic, (anti)inflammatory, adipogenic, and thermogenic genes expression by real-time reverse transcriptase-polymerase chain reaction. Additionally, metabolic activities of isolated adipocytes, such as glucose uptake, lipogenesis (triacylglycerol esterification), ß-oxidation, and lipolysis in ING adipocytes, were also assessed. Despite the higher fat intake, the HFD group showed lower food intake but higher body weight, increased glucose, significant dyslipidemia, and increased liver and adipose depot mass, accompanied by liver steatosis. The 16:1n7 supplementation slowed down the body mass gain and prevented the increase of lipids in the liver. HFD+n7 animals presented increased fatty acid oxidation and lipogenesis compared to control, but no effect was observed on lipolysis and glucose uptake in ING isolated adipocytes. Besides, 16:1n7 increased the content of the mRNA encoding FABP4, but partially prevented the expression of genes encoding ATGL, HSL, perilipin, lipin, C/EBP-α, PPAR-γ, C/EBP-ß, CPT1, NRF1, TFAM, PRDM16, and nitric oxide synthase 2 in ING depot from HFD group of animals. Finally, HFD increased Mcp1 and Tnfα expression, and 16:1n7 promoted a more marked increase in it. In summary, the data show that palmitoleic acid promotes metabolic changes and partially prevents the increase in gene expression on adipocytes triggered by obesity, suggesting that HFD+n7 animals do not require the same magnitude of metabolic adaptation to cope with energy demand from the HFD. In the long term, the effects of 16:1n7 may be more evident and beneficial for the function/dysfunction of WAT from an obese organism, with relevant repercussions in the systemic metabolic homeostasis.
Assuntos
Tecido Adiposo/efeitos dos fármacos , Ácidos Graxos Monoinsaturados/farmacologia , Ácidos Graxos/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Obesidade/metabolismo , Tecido Adiposo/metabolismo , Animais , Glicemia , Colesterol/sangue , Ácidos Graxos Monoinsaturados/uso terapêutico , Lipólise/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Camundongos Obesos , Hepatopatia Gordurosa não Alcoólica/metabolismo , Triglicerídeos/sangueRESUMO
Leukotrienes (LTs) are proinflammatory lipid mediators synthesized by the conversion of arachidonic acid (AA) to LTA(4) by the enzyme 5-lipoxygenase (5-LO) in the presence of 5-LO-activating protein (FLAP). 3-[3-tert-Butylsulfanyl-1-[4-(6-methoxy-pyridin-3-yl)-benzyl]-5-(pyridin-2-ylmethoxy)-1H-indol-2-yl]-2,2-dimethyl-propionic acid (AM103) is a novel selective FLAP inhibitor in development for the treatment of respiratory conditions such as asthma. In a rat ex vivo whole-blood calcium ionophore-induced LTB(4) assay, AM103 (administered orally at 1 mg/kg) displayed >50% inhibition for up to 6 h with a calculated EC(50) of approximately 60 nM. When rat lung was challenged in vivo with calcium ionophore, AM103 inhibited LTB(4) and cysteinyl leukotriene (CysLT) production with ED(50) values of 0.8 and 1 mg/kg, respectively. In this model, the EC(50) derived from plasma AM103 was approximately 330 nM for inhibition of both LTB(4) and CysLT. In an acute inflammation setting, AM103 displayed dose-dependent inhibition of LTB(4), CysLT, and plasma protein extravasation induced by peritoneal zymosan injection. In a model of chronic lung inflammation using ovalbumin-primed and challenged BALB/c mice, AM103 reduced the concentrations of eosinophil peroxidase, CysLTs, and interleukin-5 in the bronchoalveolar lavage fluid. Finally, AM103 increased survival time in mice exposed to a lethal intravenous injection of platelet-activating factor. In summary, AM103 is a novel, potent and selective FLAP inhibitor that has excellent pharmacodynamic properties in vivo and is effective in animal models of acute and chronic inflammation and in a model of lethal shock.