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BACKGROUND: There are little data on changes in insulin sensitivity during the first few years of life following in utero human immunodeficiency virus (HIV) and antiretroviral (ARV) exposure. METHODS: The Tshilo Dikotla study enrolled pregnant persons with HIV (PWH) (receiving tenofovir/emtricitabine or lamivudine plus dolutegravir or efavirenz) and pregnant individuals without HIV, as well as their liveborn children. Newborns were randomized to receive either zidovudine (AZT) or nevirapine (NVP) postnatal prophylaxis. Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) was assessed at birth and 1, 18, 24, and 36 months of life. We fit linear mixed-effects models to evaluate the association between in utero HIV/ARV exposure and average HOMA-IR from birth through 36 months of life, adjusting for confounders. RESULTS: A total of 419 children were included (287 with in utero HIV/ARV exposure and uninfected [CHEU] and 132 without in utero HIV/ARV exposure [CHUU]). CHEU were born to older women (29.6 vs 25.3 years of age) with higher gravidity (3 vs 1). HOMA-IR was persistently higher in CHEU versus CHUU in adjusted analyses (mean difference of 0.07 in log10 HOMA-IR, P = .02) from birth through 36 months of life. Among CHEU, no differences in HOMA-IR were observed from birth through 36 months by in utero ARV exposure status or between AZT and NVP infant prophylaxis arms. CONCLUSIONS: In utero HIV/ARV exposure was associated with lower insulin sensitivity throughout the first 36 months of life, indicating persistent early life metabolic disturbances which may raise concern for poorer metabolic health later in life.
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BACKGROUND: Few data exist on early-life metabolic perturbations in newborns with perinatal HIV and antiretroviral (ARV) exposure but uninfected (HEU) compared to those perinatally HIV unexposed and uninfected (HUU). METHODS: We enrolled pregnant persons with HIV (PWH) receiving tenofovir (TDF)/emtricitabine or lamivudine (XTC) plus dolutegravir (DTG) or efavirenz (EFV), and pregnant individuals without HIV, as well as their liveborn infants. Newborns were randomized to receive either zidovudine (AZT) or nevirapine (NVP) postnatal prophylaxis. Preprandial homeostasis model assessment for insulin resistance (HOMA-IR) was assessed at birth and 1 month. Linear mixed models were fit to assess the association between in utero HIV/ARV exposure and average HOMA-IR from birth to 1 month, adjusting for confounders. RESULTS: Of 450 newborns, 306 were HEU. HOMA-IR was higher in newborns HEU versus HUU after adjusting for confounders (mean difference of 0.068 in log HOMA-IR, P = .037). Among newborns HEU, HOMA-IR was not significantly different between TDF/XTC/DTG versus TDF/XTC/EFV in utero ARV exposure and between AZT versus NVP newborn postnatal prophylaxis arms. CONCLUSIONS: Newborns HEU versus HUU had lower insulin sensitivity at birth and at 1 month of life, raising potential concern for obesity and other metabolic perturbations later in life for newborns HEU. CLINICAL TRIALS REGISTRATION: NCT03088410.
Assuntos
Fármacos Anti-HIV , Infecções por HIV , Resistência à Insulina , Lactente , Gravidez , Feminino , Recém-Nascido , Humanos , Botsuana , Infecções por HIV/tratamento farmacológico , Antirretrovirais/uso terapêutico , Nevirapina/uso terapêutico , Zidovudina/uso terapêutico , Fármacos Anti-HIV/uso terapêuticoRESUMO
BACKGROUND: Early-life metabolic derangements in HIV-exposed uninfected (HEU) infants have been reported. METHODS: Pregnant women with HIV and HIV-uninfected pregnant women were enrolled with their newborns in a US cohort from 2011 to 2015. We measured cord insulin, C-peptide, and metabolic cytokines of HEU and HIV-unexposed uninfected (HUU) newborns using ELISA and metabolites, lipid subspecies, and eicosanoids via liquid chromatography/mass spectrometry. Linear regression was employed to assess the association of intrauterine HIV/ART with insulin and C-peptide. Graphical lasso regression was used to identify differences between metabolite/lipid subspecies networks associated with C-peptide. RESULTS: Of 118 infants, 56 were HEU, ART exposed. In adjusted analyses, mean cord insulin (ß = 0.295, p = 0.03) and C-peptide (ß = 0.522, p < 0.01) were significantly higher in HEU vs. HUU newborns. HEU neonates exhibited primarily positive associations between complex lipids and C-peptide, indicative of fuel storage, and augmented associations between cord eicosanoids and cytokines. HUU neonates exhibited negative associations with lipids and C-peptide indicative of increased fuel utilization. CONCLUSION: Higher cord insulin and C-peptide in HEU vs. HUU newborns as well as differences in cord metabolites, metabolic-related cytokines, and eicosanoids may reflect a propensity for fuel storage and an inflammatory milieu suggestive of fetal metabolic changes associated with in utero HIV/ART exposure. IMPACT: There is a paucity of studies assessing cord blood and neonatal metabolic health in HIV-exposed uninfected (HEU) newborns, an increasing population worldwide. Compared to HIV-unexposed uninfected (HUU) newborns, HEU newborns exhibit alterations in fuel homeostasis and an inflammatory milieu associated with in utero HIV/antiretroviral therapy (ART) exposure. The long-term implications of these neonatal findings are as yet unknown, but merit continued evaluation as this important and growing population ages into adulthood.
Assuntos
Infecções por HIV , Complicações Infecciosas na Gravidez , Adipocinas , Adulto , Antirretrovirais/uso terapêutico , Peptídeo C , Citocinas , Feminino , Sangue Fetal , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Humanos , Lactente , Recém-Nascido , Lipidômica , Lipídeos , GravidezRESUMO
Excessive long-term consumption of dietary carbohydrates, including glucose, sucrose, or fructose, has been shown to have significant impact on genome-wide gene expression, which likely results from changes in metabolic substrate flux. However, there has been no comprehensive study on the acute effects of individual sugars on the genome-wide gene expression that may reveal the genetic changes altering signaling pathways, subsequent metabolic processes, and ultimately physiological/pathological responses. Considering that gene expressions in response to acute carbohydrate ingestion might be different in nutrient sensitive and insensitive mammals, we conducted comparative studies of genome-wide gene expression by deep mRNA sequencing of the liver in nutrient sensitive C57BL/6J and nutrient insensitive BALB/cJ mice. Furthermore, to determine the temporal responses, we compared livers from mice in the fasted state and following ingestion of standard laboratory mouse chow supplemented with plain drinking water or water containing 20% glucose, sucrose, or fructose. Supplementation with these carbohydrates induced unique extents and temporal changes in gene expressions in a strain specific manner. Fructose and sucrose stimulated gene changes peaked at 3 h postprandial, whereas glucose effects peaked at 12 h and 6 h postprandial in C57BL/6J and BABL/cJ mice, respectively. Network analyses revealed that fructose changed genes were primarily involved in lipid metabolism and were more complex in C57BL/6J than in BALB/cJ mice. These data demonstrate that there are qualitative and antitative differences in the normal physiological responses of the liver between these two strains of mice and C57BL/6J is more sensitive to sugar intake than BALB/cJ.
Assuntos
Carboidratos da Dieta/administração & dosagem , Suplementos Nutricionais , Fígado/metabolismo , Transcriptoma/efeitos dos fármacos , Transcriptoma/genética , Animais , Carboidratos da Dieta/metabolismo , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Ingestão de Alimentos , Jejum , Frutose/administração & dosagem , Frutose/metabolismo , Glucose/administração & dosagem , Glucose/metabolismo , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transdução de Sinais/genética , Especificidade da Espécie , Sacarose/administração & dosagem , Sacarose/metabolismo , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genéticaRESUMO
Elevated mitochondrial hydrogen peroxide (H2O2) emission and an oxidative shift in cytosolic redox environment have been linked to high-fat-diet-induced insulin resistance in skeletal muscle. To test specifically whether increased flux through mitochondrial fatty acid oxidation, in the absence of elevated energy demand, directly alters mitochondrial function and redox state in muscle, two genetic models characterized by increased muscle ß-oxidation flux were studied. In mice overexpressing peroxisome proliferator-activated receptor-α in muscle (MCK-PPARα), lipid-supported mitochondrial respiration, membrane potential (ΔΨm), and H2O2 production rate (JH2O2) were increased, which coincided with a more oxidized cytosolic redox environment, reduced muscle glucose uptake, and whole body glucose intolerance despite an increased rate of energy expenditure. Similar results were observed in lipin-1-deficient, fatty-liver dystrophic mice, another model characterized by increased ß-oxidation flux and glucose intolerance. Crossing MCAT (mitochondria-targeted catalase) with MCK-PPARα mice normalized JH2O2 production, redox environment, and glucose tolerance, but surprisingly, both basal and absolute insulin-stimulated rates of glucose uptake in muscle remained depressed. Also surprising, when placed on a high-fat diet, MCK-PPARα mice were characterized by much lower whole body, fat, and lean mass as well as improved glucose tolerance relative to wild-type mice, providing additional evidence that overexpression of PPARα in muscle imposes more extensive metabolic stress than experienced by wild-type mice on a high-fat diet. Overall, the findings suggest that driving an increase in skeletal muscle fatty acid oxidation in the absence of metabolic demand imposes mitochondrial reductive stress and elicits multiple counterbalance metabolic responses in an attempt to restore bioenergetic homeostasis.NEW & NOTEWORTHY Prior work has suggested that mitochondrial dysfunction is an underlying cause of insulin resistance in muscle because it limits fatty acid oxidation and therefore leads to the accumulation of cytotoxic lipid intermediates. The implication has been that therapeutic strategies to accelerate ß-oxidation will be protective. The current study provides evidence that genetically increasing flux through ß-oxidation in muscle imposes reductive stress that is not beneficial but rather detrimental to metabolic regulation.
Assuntos
Catalase/genética , Intolerância à Glucose/genética , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , PPAR alfa/genética , Animais , Catalase/metabolismo , Metabolismo Energético/genética , Intolerância à Glucose/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias Musculares/genética , Especificidade de Órgãos/genética , Oxirredução , Estresse Oxidativo/genética , PPAR alfa/metabolismoRESUMO
Microbial metabolite mimicry is a new concept that promises to deliver compounds that have minimal liabilities and enhanced therapeutic effects in a host. In a previous publication, we have shown that microbial metabolites of L-tryptophan, indoles, when chemically altered, yielded potent anti-inflammatory pregnane X Receptor (PXR)-targeting lead compounds, FKK5 and FKK6, targeting intestinal inflammation. Our aim in this study was to further define structure-activity relationships between indole analogs and PXR, we removed the phenyl-sulfonyl group or replaced the pyridyl residue with imidazolopyridyl of FKK6. Our results showed that while removal of the phenyl-sulfonyl group from FKK6 (now called CVK003) shifts agonist activity away from PXR towards the aryl hydrocarbon receptor (AhR), the imidazolopyridyl addition preserves PXR activity in vitro. However, when these compounds are administered to mice, that unlike the parent molecule, FKK6, they exhibit poor induction of PXR target genes in the intestines and the liver. These data suggest that modifications of FKK6 specifically in the pyridyl moiety can result in compounds with weak PXR activity in vivo. These observations are a significant step forward for understanding the structure-activity relationships (SAR) between indole mimics and receptors, PXR and AhR.
Assuntos
Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Indóis/química , Indóis/farmacologia , Receptor de Pregnano X/metabolismo , Adenocarcinoma , Animais , Linhagem Celular Tumoral , Neoplasias do Colo , Desenho de Fármacos , Feminino , Hepatócitos , Humanos , Intestinos , Fígado , Masculino , Camundongos , Pessoa de Meia-Idade , Modelos Moleculares , Mimetismo Molecular , Estrutura Molecular , Receptor de Pregnano X/química , Conformação Proteica , Relação Estrutura-AtividadeRESUMO
Lipid metabolism is tightly controlled by the nutritional state of the organism. Nutrient-rich conditions increase lipogenesis, whereas nutrient deprivation promotes fat oxidation. In this study, we identify the mitochondrial sirtuin, SIRT4, as a regulator of lipid homeostasis. SIRT4 is active in nutrient-replete conditions to repress fatty acid oxidation while promoting lipid anabolism. SIRT4 deacetylates and inhibits malonyl CoA decarboxylase (MCD), an enzyme that produces acetyl CoA from malonyl CoA. Malonyl CoA provides the carbon skeleton for lipogenesis and also inhibits fat oxidation. Mice lacking SIRT4 display elevated MCD activity and decreased malonyl CoA in skeletal muscle and white adipose tissue. Consequently, SIRT4 KO mice display deregulated lipid metabolism, leading to increased exercise tolerance and protection against diet-induced obesity. In sum, this work elucidates SIRT4 as an important regulator of lipid homeostasis, identifies MCD as a SIRT4 target, and deepens our understanding of the malonyl CoA regulatory axis.
Assuntos
Carboxiliases/metabolismo , Metabolismo dos Lipídeos , Proteínas Mitocondriais/metabolismo , Sirtuínas/metabolismo , Acetilação , Tecido Adiposo Branco/metabolismo , Animais , Dieta , Ácidos Graxos/metabolismo , Metabolismo dos Lipídeos/genética , Lipídeos/biossíntese , Masculino , Camundongos , Camundongos Knockout , Proteínas Mitocondriais/genética , Obesidade/etiologia , Obesidade/metabolismo , Oxirredução , Sirtuínas/genéticaRESUMO
BACKGROUND: Alterations in gut microbiota (GMB) and host metabolites have been noted in individuals with HIV. However, it remains unclear whether alterations in GMB and related functional groups contribute to disrupted host metabolite profiles in these individuals. METHODS: This study included 185 women (128 with longstanding HIV infection, 88% under antiretroviral therapy; and 57 women without HIV from the same geographic location with comparable characteristics). Stool samples were analyzed by 16S rRNA V4 region sequencing, and GMB function was inferred by PICRUSt. Plasma metabolomic profiling was performed using liquid chromatography-tandem mass spectrometry, and 133 metabolites (amino acids, biogenic amines, acylcarnitines, and lipids) were analyzed. RESULTS: Four predominant bacterial genera were identified as associated with HIV infection, with higher abundances of Ruminococcus and Oscillospira and lower abundances of Bifidobacterium and Collinsella in women with HIV than in those without. Women with HIV showed a distinct plasma metabolite profile, which featured elevated glycerophospholipid levels compared with those without HIV. Functional analyses also indicated that GMB lipid metabolism was enriched in women with HIV. Ruminococcus and Oscillospira were among the top bacterial genera contributing to the GMB glycerophospholipid metabolism pathway and showed positive correlations with host plasma glycerophospholipid levels. One bacterial functional capacity in the acetate and propionate biosynthesis pathway was identified to be mainly contributed by Bifidobacterium; this functional capacity was lower in women with HIV than in women without HIV. CONCLUSIONS: Our integrative analyses identified altered GMB with related functional capacities that might be associated with disrupted plasma metabolite profiles in women with HIV.
Assuntos
Microbioma Gastrointestinal , Infecções por HIV , Feminino , HIV , Humanos , Metabolômica , RNA Ribossômico 16S/genéticaRESUMO
Lipin-1 ( Lpin1)-deficient lipodystrophic mice have scant and immature adipocytes and develop transient fatty liver early in life. Unlike normal mice, these mice cannot rely on stored triglycerides to generate adenosine triphosphate (ATP) from the ß-oxidation of fatty acids during periods of fasting. To compensate, these mice store much higher amounts of glycogen in skeletal muscle and liver than wild-type mice in order to support energy needs during periods of fasting. Our studies demonstrated that there are phenotypic changes in skeletal muscle fibers that reflect an adaptation to this unique metabolic situation. The phenotype of skeletal muscle (soleus, gastrocnemius, plantaris, and extensor digitorum longus [EDL]) from Lpin1-/- was evaluated using various methods including immunohistochemistry for myosin heavy chains (Myh) 1, 2, 2a, 2b, and 2x; enzyme histochemistry for myosin ATPase, cytochrome-c oxidase (COX), and succinyl dehydrogenase (SDH); periodic acid-Schiff; and transmission electron microscopy. Fiber-type changes in the soleus muscle of Lpin1-/- mice were prominent and included decreased Myh1 expression with concomitant increases in Myh2 expression and myosin-ATPase activity; this change was associated with an increase in the presence of Myh1/2a or Myh1/2x hybrid fibers. Alterations in mitochondrial enzyme activity (COX and SDH) were apparent in the myofibers in the soleus, gastrocnemius, plantaris, and EDL muscles. Electron microscopy revealed increases in the subsarcolemmal mitochondrial mass in the muscles of Lpin1-/- mice. These data demonstrate that lipin-1 deficiency results in phenotypic fiber-specific modulation of skeletal muscle necessary for compensatory fuel utilization adaptations in lipodystrophy.
Assuntos
Lipodistrofia/patologia , Músculo Esquelético/patologia , Proteínas Nucleares/deficiência , Fosfatidato Fosfatase/deficiência , Animais , Modelos Animais de Doenças , Feminino , Lipodistrofia/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Rápida/patologia , Fibras Musculares de Contração Rápida/ultraestrutura , Fibras Musculares de Contração Lenta/metabolismo , Fibras Musculares de Contração Lenta/patologia , Fibras Musculares de Contração Lenta/ultraestrutura , Músculo Esquelético/ultraestrutura , Proteínas Nucleares/genética , Fenótipo , Fosfatidato Fosfatase/genéticaRESUMO
We examined the effect of maternal smoking on plasma and urinary levels of vitamin E isoforms in preterm infants. Maternal smoking during pregnancy decreased infant plasma alpha- and gamma-tocopherol concentrations at 1 week and 4 weeks, with 45% of infants of smokers deficient in alpha-tocopherol at 1 month after birth.
Assuntos
Lactente Extremamente Prematuro/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Fumar/efeitos adversos , Vitamina E/metabolismo , Adulto , Biomarcadores/metabolismo , Feminino , Humanos , Recém-Nascido , Masculino , Estresse Oxidativo/fisiologia , Gravidez , Estudos Prospectivos , Fatores de RiscoRESUMO
One of the main causes of hyperglycemia is inefficient or impaired glucose utilization by skeletal muscle, which can be exacerbated by chronic high caloric intake. Previously, we identified a natural compound, mangiferin (MGF) that improved glucose utilization in high fat diet (HFD)-induced insulin resistant mice. To further identify the molecular mechanisms of MGF action on glucose metabolism, we conducted targeted metabolomics and transcriptomics studies of glycolyic and mitochondrial bioenergetics pathways in skeletal muscle. These data revealed that MGF increased glycolytic metabolites that were further augmented as glycolysis proceeded from the early to the late steps. Consistent with an MGF-stimulation of glycolytic flux there was a concomitant increase in the expression of enzymes catalyzing glycolysis. MGF also increased important metabolites in the tricarboxylic acid (TCA) cycle, such as α-ketoglutarate and fumarate. Interestingly however, there was a reduction in succinate, a metabolite that also feeds into the electron transport chain to produce energy. MGF increased succinate clearance by enhancing the expression and activity of succinate dehydrogenase, leading to increased ATP production. At the transcriptional level, MGF induced mRNAs of mitochondrial genes and their transcriptional factors. Together, these data suggest that MGF upregulates mitochondrial oxidative capacity that likely drives the acceleration of glycolysis flux.
Assuntos
Metabolismo Energético/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Xantonas/farmacologia , Animais , Linhagem Celular , Ciclo do Ácido Cítrico/efeitos dos fármacos , DNA Mitocondrial/metabolismo , Dieta Hiperlipídica , Gliceraldeído-3-Fosfato Desidrogenases/genética , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Metaboloma/efeitos dos fármacos , Metabolômica , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/genética , Mitocôndrias/metabolismo , Succinato Desidrogenase/genética , Succinato Desidrogenase/metabolismoRESUMO
As the lipidomics field continues to advance, self-evaluation within the community is critical. Here, we performed an interlaboratory comparison exercise for lipidomics using Standard Reference Material (SRM) 1950-Metabolites in Frozen Human Plasma, a commercially available reference material. The interlaboratory study comprised 31 diverse laboratories, with each laboratory using a different lipidomics workflow. A total of 1,527 unique lipids were measured across all laboratories and consensus location estimates and associated uncertainties were determined for 339 of these lipids measured at the sum composition level by five or more participating laboratories. These evaluated lipids detected in SRM 1950 serve as community-wide benchmarks for intra- and interlaboratory quality control and method validation. These analyses were performed using nonstandardized laboratory-independent workflows. The consensus locations were also compared with a previous examination of SRM 1950 by the LIPID MAPS consortium. While the central theme of the interlaboratory study was to provide values to help harmonize lipids, lipid mediators, and precursor measurements across the community, it was also initiated to stimulate a discussion regarding areas in need of improvement.
Assuntos
Benchmarking , Ensaio de Proficiência Laboratorial/estatística & dados numéricos , Lipídeos/sangue , Humanos , Cooperação Internacional , Metabolismo dos Lipídeos/fisiologia , Lipídeos/normas , Variações Dependentes do Observador , Padrões de Referência , Reprodutibilidade dos TestesRESUMO
Obesity and the accompanying metabolic syndrome are strongly associated with heightened morbidity and mortality in older adults. In our review of more than 20 epidemiologic studies of major infectious diseases, including leaders such as tuberculosis, community-acquired pneumonia, and sepsis, obesity was associated with better outcomes. A cause-and-effect relationship between over-nutrition and survival with infection is suggested by results of two preliminary studies of infections in mice, where high fat feeding for 8-10 weeks provided much better outcomes. The better outcomes of infections with obesity are reminiscent of many recent studies of "sterile" non-infectious medical and surgical conditions where outcomes for obese patients are better than for their thinner counterparts --- and given the tag "obesity paradox". Turning to the history of medicine and biological evolution, we hypothesize that the metabolic syndrome has very ancient origins and is part of a lifelong metabolic program. While part of that program (the metabolic syndrome) promotes morbidity and mortality with aging, it helps infants and children as well as adults in their fight against infections and recovery from injuries, key roles in the hundreds of centuries before the public health advances of the 20th century. We conclude with speculation on how understanding the biological elements that protect obese patients with infections or injuries might be applied advantageously to thin patients with the same medical challenges.
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Hepatocellular carcinoma (HCC) is one of the primary hepatic malignancies and is the third most common cause of cancer related death worldwide. Although a wealth of knowledge has been gained concerning the initiation and progression of HCC over the last half century, efforts to improve our understanding of its pathogenesis at a molecular level are still greatly needed, to enable clinicians to enhance the standards of the current diagnosis and treatment of HCC. In the post-genome era, advanced mass spectrometry driven multi-omics technologies (e.g., profiling of DNA damage adducts, RNA modification profiling, proteomics, and metabolomics) stand at the interface between chemistry and biology, and have yielded valuable outcomes from the study of a diversity of complicated diseases. Particularly, these technologies are being broadly used to dissect various biological aspects of HCC with the purpose of biomarker discovery, interrogating pathogenesis as well as for therapeutic discovery. This proof of knowledge-based critical review aims at exploring the selected applications of those defined omics technologies in the HCC niche with an emphasis on translational applications driven by advanced mass spectrometry, toward the specific clinical use for HCC patients. This approach will enable the biomedical community, through both basic research and the clinical sciences, to enhance the applicability of mass spectrometry-based omics technologies in dissecting the pathogenesis of HCC and could lead to novel therapeutic discoveries for HCC.
Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Espectrometria de Massas/métodos , Metabolômica/métodos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Adutos de DNA/análise , Adutos de DNA/metabolismo , Dano ao DNA , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Proteômica/métodos , RNA/química , RNA/metabolismoRESUMO
Diets high in fat or carbohydrates can lead to obesity and diabetes, two interrelated conditions that have been associated with osteoporosis. Here, we contrasted the effects of a high fat (HF) versus fructose-enriched carbohydrate (CH) versus regular chow (SC) diet on bone morphology, fat content and metabolic balance in BALB/cByJ mice over a 15-week period. For 13 weeks, there were no differences in body mass between groups with small differences in the last 2 weeks. Even without the potentially confounding factor of altered body mass and levels of load bearing, HF consumption was detrimental to bone in the distal femur with lower trabecular bone volume fraction and thinner cortices than controls. These differences in bone were accompanied by twofold greater abdominal fat content and fourfold greater plasma leptin concentrations. High-fat feeding caused a decrease in de-novo lipid synthesis in the liver, kidney, white adipose and brown adipose tissue. In contrast to HF, the fructose diet did not significantly impact bone quantity or architecture. Fructose consumption also did not significantly alter leptin levels or de-novo lipid synthesis but reduced epididymal adipose tissue and increased brown adipose tissue. Cortical stiffness was lower in the CH than in HF mice. There were no differences in glucose or insulin levels between groups. Together, a diet high in fat had a negative influence on bone structure, adipose tissue deposition and lipid synthesis, changes that were largely avoided with a fructose-enriched diet.
Assuntos
Tecido Adiposo/metabolismo , Osso e Ossos/metabolismo , Dieta Hiperlipídica , Frutose/metabolismo , Metabolismo dos Lipídeos/fisiologia , Animais , Peso Corporal/fisiologia , Comportamento Alimentar/fisiologia , Leptina/metabolismo , Fígado/metabolismo , Camundongos , Obesidade/metabolismoRESUMO
Isotopic ratio outlier analysis (IROA) is a (13)C metabolomics profiling method that eliminates sample to sample variance, discriminates against noise and artifacts, and improves identification of compounds, previously done with accurate mass liquid chromatography/mass spectrometry (LC/MS). This is the first report using IROA technology in combination with accurate mass gas chromatography/time-of-flight mass spectrometry (GC/TOF-MS), here used to examine the S. cerevisiae metabolome. S. cerevisiae was grown in YNB media, containing randomized 95% (13)C, or 5%(13)C glucose as the single carbon source, in order that the isotopomer pattern of all metabolites would mirror the labeled glucose. When these IROA experiments are combined, the abundance of the heavy isotopologues in the 5%(13)C extracts, or light isotopologues in the 95%(13)C extracts, follows the binomial distribution, showing mirrored peak pairs for the molecular ion. The mass difference between the (12)C monoisotopic and the (13)C monoisotopic equals the number of carbons in the molecules. The IROA-GC/MS protocol developed, using both chemical and electron ionization, extends the information acquired from the isotopic peak patterns for formulas generation. The process that can be formulated as an algorithm, in which the number of carbons, as well as the number of methoximations and silylations are used as search constraints. In electron impact (EI/IROA) spectra, the artifactual peaks are identified and easily removed, which has the potential to generate "clean" EI libraries. The combination of chemical ionization (CI) IROA and EI/IROA affords a metabolite identification procedure that enables the identification of coeluting metabolites, and allowed us to characterize 126 metabolites in the current study.
Assuntos
Metabolômica , Saccharomyces cerevisiae/metabolismo , Algoritmos , Artefatos , Cromatografia Gasosa-Espectrometria de Massas , Marcação por IsótopoRESUMO
It has been assumed, based largely on morphologic evidence, that human pluripotent stem cells (hPSCs) contain underdeveloped, bioenergetically inactive mitochondria. In contrast, differentiated cells harbour a branched mitochondrial network with oxidative phosphorylation as the main energy source. A role for mitochondria in hPSC bioenergetics and in cell differentiation therefore remains uncertain. Here, we show that hPSCs have functional respiratory complexes that are able to consume O(2) at maximal capacity. Despite this, ATP generation in hPSCs is mainly by glycolysis and ATP is consumed by the F(1)F(0) ATP synthase to partially maintain hPSC mitochondrial membrane potential and cell viability. Uncoupling protein 2 (UCP2) plays a regulating role in hPSC energy metabolism by preventing mitochondrial glucose oxidation and facilitating glycolysis via a substrate shunting mechanism. With early differentiation, hPSC proliferation slows, energy metabolism decreases, and UCP2 is repressed, resulting in decreased glycolysis and maintained or increased mitochondrial glucose oxidation. Ectopic UCP2 expression perturbs this metabolic transition and impairs hPSC differentiation. Overall, hPSCs contain active mitochondria and require UCP2 repression for full differentiation potential.
Assuntos
Diferenciação Celular , Metabolismo Energético , Canais Iônicos/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Trifosfato de Adenosina , Linhagem Celular , Glicólise , Humanos , Hidrólise , Canais Iônicos/genética , Proteínas Mitocondriais/genética , Consumo de Oxigênio , Células-Tronco Pluripotentes/ultraestrutura , Espécies Reativas de Oxigênio/metabolismo , Proteína Desacopladora 2RESUMO
The liver plays a central role in metabolism and mediating insulin action. To dissect the effects of insulin on the liver in vivo, we have studied liver insulin receptor knockout (LIRKO) mice. Because LIRKO livers lack insulin receptors, they are unable to respond to insulin. Surprisingly, the most profound derangement observed in LIRKO livers by microarray analysis is a suppression of the cholesterologenic genes. Sterol regulatory element binding protein (SREBP)-2 promotes cholesterologenic gene transcription, and is inhibited by intracellular cholesterol. LIRKO livers show a slight increase in hepatic cholesterol, a 40% decrease in Srebp-2, and a 50-90% decrease in the cholesterologenic genes at the mRNA and protein levels. In control mice, SREBP-2 and cholesterologenic gene expression are suppressed by fasting and restored by refeeding; in LIRKO mice, this response is abolished. Similarly, the ability of statins to induce Srebp-2 and the cholesterologenic genes is lost in LIRKO livers. In contrast, ezetimibe treatment robustly induces Srepb-2 and its targets in LIRKO livers, raising the possibility that insulin may regulate SREBP-2 indirectly, by altering the accumulation or distribution of cholesterol within the hepatocyte. Taken together, these data indicate that cholesterol synthesis is a key target of insulin action in the liver.
Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Fígado/metabolismo , Lovastatina/farmacologia , Receptor de Insulina/deficiência , Proteína de Ligação a Elemento Regulador de Esterol 2/fisiologia , Animais , Azetidinas/farmacologia , Vias Biossintéticas/genética , Colesterol/biossíntese , Ezetimiba , Jejum , Expressão Gênica/efeitos dos fármacos , Lipogênese/efeitos dos fármacos , Camundongos , Camundongos da Linhagem 129 , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Análise de Sequência com Séries de Oligonucleotídeos , Receptor de Insulina/genética , Ativação Transcricional/efeitos dos fármacos , TranscriptomaRESUMO
INTRODUCTION: Dolutegravir (DTG)-based antiretroviral therapy is the World Health Organization's preferred first-line regimen for all persons with HIV, including pregnant women. While DTG has been implicated as an obesogen associated with greater weight gain compared to other antiretrovirals, there is a paucity of data in pregnant women and their children. The Obesogenic oRigins of maternal and Child metabolic health Involving Dolutegravir (ORCHID) study is investigating associations between DTG, weight gain, and metabolic outcomes in the context of HIV. MATERIALS & METHODS: ORCHID is a prospective observational study taking place in Cape Town, South Africa (NCT04991402). A total of 1920 pregnant women with and without HIV infection are being followed from ≤18 weeks gestational age to 24 months postpartum with their children. Participants attend eleven study visits: 3 antenatal, delivery, and 7 postnatal visits. Several embedded sub-studies address specific scientific aims. Primary outcome measurements in mothers include anthropometry, blood pressure, body composition, dysglycemia, insulin resistance (IR), and dyslipidemia. Other maternal measures include demographics, resting energy expenditure, viral load, physical activity, dietary intake, hepatic steatosis, and repository specimens. Sub-study measurements include markers of adipose inflammation, gut integrity, and satiety/hunger, subcutaneous adipose tissue morphology and mitochondrial function, and metabolomics. Primary outcome measurements in children include anthropometry, adipose tissue mass, dysglycemia, IR, and dyslipidemia. Other variables include fetal growth, birth outcomes, medical/breastfeeding history, caloric intake, neurodevelopment, and repository specimens. Sub-study measurements include metabolites/lipid subspecies in umbilical cord blood, as well as breast milk composition and DTG exposure. DISCUSSION: ORCHID will play a pivotal role in defining obesogenic mechanisms and clinical consequences of DTG use in pregnancy in women with HIV and their children. It will provide insights into metabolic disease risk reduction in the context of HIV/DTG, identify intervention targets, and inform public health approaches to diminish chronic metabolic co-morbidities for women and children.