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1.
Orv Hetil ; 160(25): 973-979, 2019 Jun.
Artigo em Húngaro | MEDLINE | ID: mdl-31203640

RESUMO

Progranulin is a recently recognized multifunctional glycopeptide shown to be related to obesity and diabetes mellitus. Progranulin is an endogenous antagonist of tumor necrosis factor-α by competitively binding to its receptor, therefore, it exerts anti-inflammatory activity. Paradoxically, previous studies have shown that serum levels of progranulin were elevated in patients with diabetes and associated to its complications including micro- and macroangiopathies, macroalbuminuria or reduced renal function. Moreover, hyperprogranulinemia may be involved in the pathogenesis of obesity-associated insulin resistance. The review summarizes the currently available data on progranulin as a novel marker of the carbohydrate metabolism and inflammation. Orv Hetil. 2019; 160(25): 973-979.


Assuntos
Metabolismo dos Carboidratos/fisiologia , Progranulinas/sangue , Biomarcadores/sangue , Humanos , Inflamação/sangue , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Prognóstico
2.
Plant Sci ; 285: 224-229, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31203887

RESUMO

Why evergreen fruit tree species accumulate starch in the ovary during flower bud differentiation in spring, as deciduous species do during flower bud dormancy, is not fully understood. This is because in evergreen species carbon supply is assured by leaves during flower development. We suggest the existence of an autonomous mechanism in the flowers which counteracts the competition for photoassimilates with new leaves, until they become source organs. Our hypothesis is that starch accumulated during Citrus ovary ontogeny originates from 1) its own photosynthetic capacity and 2) the mobilization of reserves. Through defoliation experiments, we found that ovaries accumulate starch during flower ontogeny using a dual mechanism: 1) the autotrophic route of source organs activating Rubisco (RbcS) genes expression, and 2) the heterotrophic route of sink organs that hydrolyze sucrose in the cytosol. Defoliation 40 days before anthesis did not significantly reduce ovary growth, flower abscission or starch concentration up to 20 days after anthesis (i.e. 60 days later). Control flowers activated the energy depletion signaling system (i.e. SnRK1) and RbcS gene expression around athesis. Defoliation accelerated and boosted both activities, increasing SPS gene expression (sucrose synthesis), and SUS1, SUS3 and cwINV (sucrose hydrolysis) to maintain a glucose threshold which satisfied its need to avoid abscission.


Assuntos
Metabolismo dos Carboidratos/fisiologia , Citrus/crescimento & desenvolvimento , Flores/fisiologia , Frutas/crescimento & desenvolvimento , Citrus/metabolismo , Citrus/fisiologia , Flores/crescimento & desenvolvimento , Flores/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transcriptoma
3.
Nat Commun ; 10(1): 2756, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227702

RESUMO

Flight loss in birds is as characteristic of the class Aves as flight itself. Although morphological and physiological differences are recognized in flight-degenerate bird species, their contributions to recurrent flight degeneration events across modern birds and underlying genetic mechanisms remain unclear. Here, in an analysis of 295 million nucleotides from 48 bird genomes, we identify two convergent sites causing amino acid changes in ATGLSer321Gly and ACOT7Ala197Val in flight-degenerate birds, which to our knowledge have not previously been implicated in loss of flight. Functional assays suggest that Ser321Gly reduces lipid hydrolytic ability of ATGL, and Ala197Val enhances acyl-CoA hydrolytic activity of ACOT7. Modeling simulations suggest a switch of main energy sources from lipids to carbohydrates in flight-degenerate birds. Our results thus suggest that physiological convergence plays an important role in flight degeneration, and anatomical convergence often invoked may not.


Assuntos
Evolução Biológica , Aves/fisiologia , Metabolismo Energético/genética , Voo Animal/fisiologia , Genoma/genética , Animais , Metabolismo dos Carboidratos/fisiologia , Genômica/métodos , Lipase/genética , Lipase/metabolismo , Lipólise/fisiologia , Palmitoil-CoA Hidrolase/genética , Palmitoil-CoA Hidrolase/metabolismo , Filogenia
4.
Cell Mol Life Sci ; 76(21): 4319-4340, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31062073

RESUMO

The human gut microbiota, which underpins nutrition and systemic health, is compositionally sensitive to the availability of complex carbohydrates in the diet. The Bacteroidetes comprise a dominant phylum in the human gut microbiota whose members thrive on dietary and endogenous glycans by employing a diversity of highly specific, multi-gene polysaccharide utilization loci (PUL), which encode a variety of carbohydrases, transporters, and sensor/regulators. PULs invariably also encode surface glycan-binding proteins (SGBPs) that play a central role in saccharide capture at the outer membrane. Here, we present combined biophysical, structural, and in vivo characterization of the two SGBPs encoded by the Bacteroides ovatus mixed-linkage ß-glucan utilization locus (MLGUL), thereby elucidating their key roles in the metabolism of this ubiquitous dietary cereal polysaccharide. In particular, molecular insight gained through several crystallographic complexes of SGBP-A and SGBP-B with oligosaccharides reveals that unique shape complementarity of binding platforms underpins specificity for the kinked MLG backbone vis-à-vis linear ß-glucans. Reverse-genetic analysis revealed that both the presence and binding ability of the SusD homolog BoSGBPMLG-A are essential for growth on MLG, whereas the divergent, multi-domain BoSGBPMLG-B is dispensable but may assist in oligosaccharide scavenging from the environment. The synthesis of these data illuminates the critical role SGBPs play in concert with other MLGUL components, reveals new structure-function relationships among SGBPs, and provides fundamental knowledge to inform future (meta)genomic, biochemical, and microbiological analyses of the human gut microbiota.


Assuntos
Bacteroides/fisiologia , Grão Comestível/metabolismo , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Proteínas de Membrana/fisiologia , Polissacarídeos/metabolismo , beta-Glucanas/metabolismo , Bacteroides/genética , Bacteroides/metabolismo , Metabolismo dos Carboidratos/fisiologia , Sequência de Carboidratos , Fibras na Dieta/metabolismo , Microbioma Gastrointestinal/fisiologia , Regulação Bacteriana da Expressão Gênica , Loci Gênicos , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Humanos , Proteínas de Membrana/metabolismo
5.
Acta Diabetol ; 56(9): 1013-1022, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30989379

RESUMO

AIM: More than 40% of pancreatic ductal adenocarcinoma (PDAC) patients have glucose intolerance or diabetes. The association has led to two hypotheses: PDAC causes diabetes or diabetes shares risk factors for the development of PDAC. In order to elucidate the relationship between diabetes and PDAC, we investigated the glucose metabolism during tumorigenesis in the LSL-KrasG12D/+; LSL-Trp53R172H/+; and Pdx-1-Cre (KPC) mouse, a genetically engineered model of PDAC. METHODS: Male and female KPCs have been fed with standard diet (SD) or high-fat diet (HFD). The imaging-based 4-class tumor staging was used to follow pancreatic cancer development. Not fasting glycemia, 4-h fasting glycemia, insulin, C-peptide, glucose tolerance after OGTT and abdominal fat volume were measured during tumorigenesis. RESULTS: PDAC development did not lead to an overt diabetic phenotype or to any alterations in glucose tolerance in KPC fed with SD. Consumption of HFD induced higher body weight/abdominal fat volume and worsened glucose homeostasis both in control CRE mice and only in early tumorigenesis stages of the KPC mice, excluding that the cancer development itself acts as a trigger for the onset of dysmetabolic features. CONCLUSION: Our data demonstrate that carcinogenesis in KPC mice is not associated with paraneoplastic diabetes.


Assuntos
Metabolismo dos Carboidratos/fisiologia , Carcinogênese/metabolismo , Glucose/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Animais , Metabolismo dos Carboidratos/genética , Carcinogênese/genética , Carcinoma Ductal Pancreático/metabolismo , Modelos Animais de Doenças , Feminino , Proteínas de Homeodomínio/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Estadiamento de Neoplasias , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Transativadores/genética , Proteína Supressora de Tumor p53/genética
6.
Tuberculosis (Edinb) ; 115: 161-170, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30948172

RESUMO

Tuberculosis (TB) protein biomarkers are urgently needed for the development of point-of-care diagnostics, new drugs and vaccines. Mycobacterium tuberculosis extracellular and secreted proteins play an important role in host-pathogen interactions. Antibodies produced against M. tuberculosis proteins before the onset of clinical symptoms can be used in proteomic studies to identify their target proteins. In this study, M. tuberculosis F15/LAM4/KZN strain phage secretome library was screened against immobilized polyclonal sera from active TB patients (n = 20), TST positive individuals (n = 15) and M. tuberculosis uninfected individuals (n = 20) to select and identify proteins recognized by patients' antibodies. DNA sequence analysis from randomly selected latent TB and active TB specific phage clones revealed 118 and 96 ORFs, respectively. Proteins essential for growth, virulence and metabolic pathways were identified using different TB databases. The identified active TB specific biomarkers included five proteins, namely, TrpG, Alr, TreY, BfrA and EspR, with no human homologs, whilst latent TB specific biomarkers included NarG, PonA1, PonA2 and HspR. Future studies will assess potential applications of identified protein biomarkers as TB drug or vaccine candidates/targets and diagnostic markers with the ability to discriminate LTBI from active TB.


Assuntos
Tuberculose Latente/diagnóstico , Mycobacterium tuberculosis/isolamento & purificação , Adulto , Aminoácidos/metabolismo , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/metabolismo , Biomarcadores/metabolismo , Metabolismo dos Carboidratos/fisiologia , Parede Celular/metabolismo , Diagnóstico Precoce , Metabolismo Energético/fisiologia , Feminino , Ontologia Genética , Genes Bacterianos/genética , Genoma Bacteriano , Biblioteca Genômica , Humanos , Imunidade Celular/fisiologia , Ferro/metabolismo , Tuberculose Latente/imunologia , Metabolismo dos Lipídeos/fisiologia , Masculino , Redes e Vias Metabólicas/fisiologia , Mycobacterium tuberculosis/imunologia , Virulência/fisiologia , Fatores de Virulência/metabolismo
7.
Plant Physiol Biochem ; 139: 82-91, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30884415

RESUMO

Wild soybean (Glycine soja) and cultivated soybean (Glycine max) belong to the subgenus Soja. We investigated the photosynthetic activity, mineral nutrition and metabolomics of the salt-tolerant wild soybean (W2), salt-sensitive wild soybean (W1) and cultivated soybean (C) in the early flowering stage, with a focus on the physiological and cellular metabolism-related differences among Soja to reveal the adaptive mechanisms. The photosynthetic activity of W2 was greater than that of W1 and the Mg, Zn, Mo, Mn and B contents showed the same trend. Carbohydrate, polyol, organic acid and fatty acid contents, as well as the secondary metabolism, were greater in W2 than W1, while the amino acid metabolism was lower in W2 than W1. These levels could minimize damage and maximize survival and growth, which might be the mechanisms that W2 adapts under adverse environmental conditions. The photosynthetic activity of C was greater than that of W1 and C also contained more K, Zn and B. The metabolomics study indicated that carbohydrate and organic acid metabolism were relatively greater, while the amino acid content and secondary metabolism level were lower in C than W1. These were presumably the result of long-term breeding and domestication. This comparative study among Soja will help in increasing the understanding and protection of wild soybean resources, as well as the improvement and utilization of cultivated soybean.


Assuntos
Flores/crescimento & desenvolvimento , Soja/metabolismo , Aminoácidos/metabolismo , Metabolismo dos Carboidratos/fisiologia , Ácidos Graxos/metabolismo , Flores/metabolismo , Flores/fisiologia , Metabolômica , Fotossíntese , Folhas de Planta/metabolismo , Folhas de Planta/fisiologia , Soja/crescimento & desenvolvimento , Soja/fisiologia
8.
Nutrients ; 11(3)2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30823446

RESUMO

The prevalence and incidence of metabolic syndrome is reaching pandemic proportions worldwide, thus warranting an intensive search for novel preventive and treatment strategies. Recent studies have identified a number of soluble factors secreted by adipocytes and myocytes (adipo-/myokines), which link sedentary life style, abdominal obesity, and impairments in carbohydrate and lipid metabolism. In this review, we discuss the metabolic roles of the recently discovered myokine ß-aminoisobutyric acid (BAIBA), which is produced by skeletal muscle during physical activity. In addition to physical activity, the circulating levels of BAIBA are controlled by the mitochondrial enzyme alanine: glyoxylate aminotransferase 2 (AGXT2), which is primarily expressed in the liver and kidneys. Recent studies have shown that BAIBA can protect from diet-induced obesity in animal models. It induces transition of white adipose tissue to a "beige" phenotype, which induces fatty acids oxidation and increases insulin sensitivity. While the exact mechanisms of BAIBA-induced metabolic effects are still not well understood, we discuss some of the proposed pathways. The reviewed data provide new insights into the connection between physical activity and energy metabolism and suggest that BAIBA might be a potential novel drug for treatment of the metabolic syndrome and its cardiovascular complications.


Assuntos
Ácidos Aminoisobutíricos/metabolismo , Metabolismo dos Carboidratos/fisiologia , Metabolismo dos Lipídeos/fisiologia , Animais , Metabolismo Energético/fisiologia , Humanos , Músculo Esquelético/fisiologia
9.
Life Sci ; 220: 58-68, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30703383

RESUMO

AIMS: Type 2 diabetes and obesity are associated with chronic hypoxia, which contributes to adipose tissue dysfunction and development of insulin resistance and metabolic disorders. We assessed long-term effects of hyperoxia on browning of adipocytes and carbohydrate metabolism in a murine model of type 2 diabetes. MAIN METHODS: Male Wistar rats (190-210 g) were divided into 4 groups: Control, O2-treated control, untreated diabetes, and O2-treated diabetes. Diabetes was induced using high-fat diet followed by a low-dose of streptozotocin (30 mg/kg). Hyperoxia sessions were included 2-h exposure to 95% oxygen, repeated 6 days/week for 5 weeks. Serum fasting glucose, insulin, lactate, and lipid profile were measured before, during, and after hyperoxia. Glucose and pyruvate tolerance tests, and histological evaluations of interscapular and epididymal fats were done at the end of study. KEY FINDINGS: O2-treated diabetic rats compared to untreated ones, displayed lower weight gain, improved glucose-tolerance, insulin sensitivity, and more favorable lipid profile. In diabetic rats, hyperoxia increased surface area (6.36 ±â€¯0.93 vs. 0.86 ±â€¯0.16 mm2, P < 0.001), and volume density (1.53 ±â€¯0.22 vs. 0.21 ±â€¯0.04 mm3, P < 0.001) of interscapular adipose tissue; hyperoxia also increased protein levels of uncoupling protein 1 (UCP1), peroxisome proliferator activated receptor gamma (PPAR-γ), and PPAR-γ coactivator 1 alpha (PGC1-α) in interscapular adipose tissue. The numerical density (541.7 ±â€¯7.3 vs. 298.1 ±â€¯11.7 mm3, P < 0.001) of epididymal fat were also higher. SIGNIFICANCE: This study showed that beneficial metabolic effects of hyperoxia in obese type 2 diabetic rats including improved insulin sensitivity and glucose tolerance are at least in part due to browning of adipose tissue.


Assuntos
Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Hiperóxia/metabolismo , Adipócitos Marrons , Adipócitos Brancos , Animais , Metabolismo dos Carboidratos/fisiologia , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Glucose/metabolismo , Teste de Tolerância a Glucose , Insulina/metabolismo , Resistência à Insulina , Masculino , Obesidade/metabolismo , Ratos , Ratos Wistar , Estreptozocina/farmacologia
10.
Gene ; 696: 135-148, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30776461

RESUMO

Organisms use a variety of carbohydrates and metabolic pathways in order to capitalize in their specific environments. Depending upon their habitat, organism employs different types of transporters to maintain the cellular nutritional balance via central metabolism. A major contributor in this process in bacteria is a carbohydrate ABC transporter. The focus of this study is to get an insight into the carbohydrate transport and metabolism of a hot-spring-dwelling bacterium Thermus thermophilus HB8. We applied high-throughput data-mining approaches for identification and characterization of carbohydrate ABC transporters in T. thermophilus HB8. This enabled the identification of 11 putative carbohydrate ABC transport systems. To identify the cognate ligands for these transporters, functional annotation was performed. However, scarcity of homologous-protein's function hinders the process of functional annotation. Thus, to overcome this limitation, we integrated the functional annotation of carbohydrate ABC transporters with their metabolic analysis. Our results demonstrate that out of 11 putative carbohydrate ABC transporters, six are involved in the sugar (four for monosaccharides and polysaccharides-degraded products and two for osmotic regulation), four in phospholipid precursor (namely UgpABCE) and the remaining one in purine uptake. Further, analysis suggests the existence of sharing mechanism of transmembrane domains (TMDs) and/or nucleotide-binding domains (NBDs) among the 11 carbohydrate ABC transporters.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Metabolismo dos Carboidratos/fisiologia , Redes e Vias Metabólicas/fisiologia , Domínios Proteicos/fisiologia , Thermus thermophilus/fisiologia , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/genética , Sequência de Aminoácidos/genética , Simulação de Acoplamento Molecular , Fosfolipídeos/metabolismo , Ligação Proteica , Purinas/metabolismo , Especificidade por Substrato
11.
Biomed Res Int ; 2019: 1451623, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30805360

RESUMO

The insulin pathway is an anabolic pathway that controls, amongst other things, glucose homeostasis. It is an evolutionarily conserved pathway. Disruptions in insulin pathway functions can lead to diabetic states. Diabetes, a very common occurrence in modern life, afflicts a significant portion of the population of developed and developing countries worldwide. Yet, few studies have addressed the evolution of diabetic states on a long-term basis. Here, we cultured three different insulin pathway signaling compromised flies (heteroallelic mutant combinations, akin to diabetes mellitus type II) and wild type control flies, for the extent of one generation in different isocaloric diets fed at libitum, with or without extra methionine added. All fly stocks have a homogenized genetic background. We measured weight, total lipid, and carbohydrate content of adults at two different time points, and survival of adults reared in some of the different diets. Results show that, despite the fact that all diet regimes allow survival of at least a fraction of flies to adulthood, life histories are significantly different. Higher protein content diets promote better survival compared to higher percentage lipid and carbohydrate diets, and added methionine promotes survival in moderately reduced protein content diets. In mutants, survival is significantly reduced, and added methionine generally has an effect, albeit a more modest one. Our results highlight the value of higher percentage protein diets, and differences in effects in "healthy" versus "diabetic" states. They also show that added methionine, proposed as a "sensor" for protein content in food for flies, leads to differential effects depending on the adequacy of the diet regime.


Assuntos
Dípteros/metabolismo , Insulina/metabolismo , Transdução de Sinais/fisiologia , Animais , Peso Corporal/fisiologia , Metabolismo dos Carboidratos/fisiologia , Diabetes Mellitus Tipo 2/metabolismo , Dieta/métodos , Proteínas na Dieta/metabolismo , Metabolismo dos Lipídeos/fisiologia , Metionina/metabolismo
12.
Microbiol Spectr ; 7(1)2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30657107

RESUMO

As a major etiological agent of human dental caries, Streptococcus mutans resides primarily in biofilms that form on the tooth surfaces, also known as dental plaque. In addition to caries, S. mutans is responsible for cases of infective endocarditis with a subset of strains being indirectly implicated with the onset of additional extraoral pathologies. During the past 4 decades, functional studies of S. mutans have focused on understanding the molecular mechanisms the organism employs to form robust biofilms on tooth surfaces, to rapidly metabolize a wide variety of carbohydrates obtained from the host diet, and to survive numerous (and frequent) environmental challenges encountered in oral biofilms. In these areas of research, S. mutans has served as a model organism for ground-breaking new discoveries that have, at times, challenged long-standing dogmas based on bacterial paradigms such as Escherichia coli and Bacillus subtilis. In addition to sections dedicated to carbohydrate metabolism, biofilm formation, and stress responses, this article discusses newer developments in S. mutans biology research, namely, how S. mutans interspecies and cross-kingdom interactions dictate the development and pathogenic potential of oral biofilms and how next-generation sequencing technologies have led to a much better understanding of the physiology and diversity of S. mutans as a species.


Assuntos
Biofilmes/crescimento & desenvolvimento , Cárie Dentária/microbiologia , Placa Dentária/microbiologia , Streptococcus mutans/fisiologia , Streptococcus mutans/patogenicidade , Metabolismo dos Carboidratos/fisiologia , Cárie Dentária/patologia , Placa Dentária/patologia , Humanos , Transdução de Sinais/fisiologia , Streptococcus mutans/metabolismo
13.
Physiol Plant ; 165(3): 644-663, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29766507

RESUMO

Heat stress at the pollen mother cell (PMC) meiotic stage leads to pollen sterility in rice, in which the reactive oxygen species (ROS) and sugar homeostasis are always adversely affected. This damage is reversed by abscisic acid (ABA), but the mechanisms underlying the interactions among the ABA, sugar metabolism, ROS and heat shock proteins in rice spikelets under heat stress are unclear. Two rice genotypes, Zhefu802 (a recurrent parent) and fgl (its near-isogenic line) were subjected to heat stress of 40°C after pre-foliage sprayed with ABA and its biosynthetic inhibitor fluridone at the meiotic stage of PMC. The results revealed that exogenous application of ABA reduced pollen sterility caused by heat stress. This was achieved through various means, including: increased levels of soluble sugars, starch and non-structural carbohydrates, markedly higher relative expression levels of heat shock proteins (HSP24.1 and HSP71.1) and genes related to sugar metabolism and transport, such as sucrose transporters (SUT) genes, sucrose synthase (SUS) genes and invertase (INV) genes as well as increased antioxidant activities and increased content of adenosine triphosphate and endogenous ABA in spikelets. In short, exogenous application of ABA prior to heat stress enhanced sucrose transport and accelerated sucrose metabolism to maintain the carbon balance and energy homeostasis, thus ABA contributed to heat tolerance in rice.


Assuntos
Ácido Abscísico/metabolismo , Oryza/metabolismo , Pólen/metabolismo , Ácido Abscísico/genética , Metabolismo dos Carboidratos/genética , Metabolismo dos Carboidratos/fisiologia , Regulação da Expressão Gênica de Plantas , Oryza/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Pólen/genética , Temperatura Ambiente
14.
Appl Microbiol Biotechnol ; 103(3): 1455-1464, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30535579

RESUMO

Biodegradation of cellulose-rich substrates is an indispensable process for soil carbon replenishment in various ecological niches. Biodegradation of cellulose has been studied extensively via an enzyme assay to quantify the amount of cellulase with a view to identify effective cellulose degraders. However, a bulk enzyme assay undermines the role of physiological heterogeneity between cells; it is therefore imperative to opt out for a more effective method such as single-cell Raman spectroscopy combined with heavy water (D2O) to reveal active cellulose degraders. Cellular incorporation of D2O-derived D produces a new C-D Raman band which can act as a quantitative indicator of microbial activity. In this study, metabolic responses of seven cellulose-degrading bacteria to carboxymethylcellulose (CMC) and glucose were evaluated via the C-D Raman band. On the basis of % C-D, CMC was demonstrated to be most efficiently metabolized by Bacillus velezensis 2a-9 and Providencia vermicola 5a-9(b). Metabolic activity between individual cells of B. velezensis and P. vermicola towards CMC ranged from approximately 8 to 27% and 6 to 16%, respectively, clearly indicating heterogeneous degradation activities among isogenic populations. Linear correlation between % C-D and specific endoglucanase activity validated Raman results on CMC-degrading activity. Also, % C-D obtained from bacteria cultivated with only glucose was around 60% higher than that obtained from CMC, indicating the preference of bacteria for simple sugar glucose than CMC. In conclusion, Raman spectroscopy combined with heavy water is a sensitive analytical technique to reveal cellulose degraders and their degrading activities.


Assuntos
Bacillus/metabolismo , Carboximetilcelulose Sódica/metabolismo , Celulase/metabolismo , Glucose/metabolismo , Providencia/metabolismo , Análise Espectral Raman/métodos , Bacillus/enzimologia , Biodegradação Ambiental , Metabolismo dos Carboidratos/fisiologia , Óxido de Deutério/química , Marcação por Isótopo/métodos , Providencia/enzimologia , Microbiologia do Solo
15.
Obes Surg ; 29(2): 406-413, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30251098

RESUMO

PURPOSE: Laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy (LSG) are the most popular procedures to treat morbid obesity among bariatric surgeries. However, only few studies have compared the changes in body composition, dietary intake, and substrate oxidation after LRYGB and LSG. Therefore, the present study was conducted to compare the changes in body composition, dietary intake, and substrate oxidation 6 months postoperatively in obese patients who underwent LRYGB and LSG. MATERIALS AND METHODS: In this prospective study, a total of 43 adult obese patients participated (LRYGB = 22 and LSG = 21). Their body composition was measured by bioelectric impedance analysis. Dietary intake was assessed using 3-day food record. Substrate oxidation was measured by indirect calorimetry. All participants were followed up for 6 months. RESULTS: The percentage of weight loss was 22.8 ± 4.5 and 23.3 ± 5.7% in LRYGB and LSG, respectively. Fat mass (FM), fat-free mass (FFM), and percentage of fat mass (PFM) significantly reduced in LRYGB and LSG, while the percentage of fat-free mass (PFFM) significantly increased in both surgeries. Dietary energy intake significantly reduced by 63.5 ± 30.6% in LRYGB and 66.7 ± 20.1% in LSG. Dietary intake of protein, carbohydrate, fat, and fiber significantly decreased in each group. The percentage of energy from protein, carbohydrate, and fat did not change in each group. Protein oxidation and carbohydrate oxidation significantly reduced in both procedures postoperatively. Changes in body composition, dietary intake, and substrate oxidation from baseline were equal in LRYGB and LSG. CONCLUSION: Therefore, LRYGB and LSG have similar effect on total and regional FM and FFM, dietary macronutrients intake, and substrate oxidation.


Assuntos
Composição Corporal , Ingestão de Alimentos , Metabolismo Energético/fisiologia , Gastrectomia , Derivação Gástrica , Obesidade Mórbida/metabolismo , Obesidade Mórbida/cirurgia , Adulto , Idoso , Índice de Massa Corporal , Calorimetria Indireta , Metabolismo dos Carboidratos/fisiologia , Proteínas na Dieta/metabolismo , Impedância Elétrica , Comportamento Alimentar , Feminino , Gastrectomia/métodos , Derivação Gástrica/métodos , Humanos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Oxirredução , Período Pós-Operatório , Estudos Prospectivos , Perda de Peso/fisiologia
16.
J Plant Physiol ; 232: 301-310, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30551095

RESUMO

An experiment was conducted with seedlings of Citrus macrophylla Wester to study the effects of P nutrition on plants inoculated with a mixture (Rhizophagus irregularis and Funneliformis mosseae) of arbuscular mycorrhizal (AM) fungi. The treatments consisted of factorial combinations of two factors: mycorrhization (-AM: non-inoculated plants, and +AM: inoculated plants) and P nutrition (0, 0.1, 1, and 5 mM P). After the P treatments had been applied for 165 days, the AM fungi showed an important effect on plant growth and P uptake, but this effect depended on the P fertilization. In the absence of P fertilization, inoculation with the AM fungi had little impact on P nutrition and plant growth. However, when 0.1 or 1 mM P was supplied, inoculation had a clear beneficial effect on plant growth, since P nutrition was significantly improved, the maximum growth of the +AM plants occurring at 1 mM P. The supply of 5 mM P did not increase plant growth with regard to 1 mM P due to a lack of improvement in leaf P nutrition and photosynthesis. The higher demand of the AM fungi in the roots of the +AM plants for sucrose reduced the concentration of sucrose in the leaves of plants receiving 5 mM P, and of fructose and glucose in the roots of plants supplied with 0.1 or 1 mM P, relative to the -AM plants. The inoculated plants grown with 5 mM P had a decreased starch concentration in their roots, in order to supply the high sugar demand of the AM fungi. The C drain towards the AM fungi in the +AM plants may have been compensated by a higher photosynthetic rate and improved mineral nutrition. Inoculation improved plant P nutrition in the 0.1 and 1 mM P treatments but had a lesser effect at 5 mM P. The tissue levels of certain nutrients, such as Mg, improved with inoculation regardless of the P treatment, but those of other nutrients - such as Zn or Fe - increased more in the +AM plants with lower P supply. So, in general, the +AM C. macrophylla plants receiving the highest P supply did not show improved mineral nutrition relative to the -AM plants. Overall, the results indicate that when the availability of P to C. macrophylla plants is high, the lower benefits received by the plants from the C-for-P trade can convert a mutualistic relationship between the host plant and AM fungi into a parasitic one since colonization can persist even when the availability of P in the soil is high.


Assuntos
Citrus/microbiologia , Micorrizas/metabolismo , Fósforo/deficiência , Metabolismo dos Carboidratos/fisiologia , Citrus/crescimento & desenvolvimento , Citrus/metabolismo , Citrus/fisiologia , Micorrizas/fisiologia , Fósforo/metabolismo , Plântula/crescimento & desenvolvimento , Plântula/microbiologia
17.
J Plant Physiol ; 232: 188-199, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30537606

RESUMO

We studied metabolic adaptations to cold stress in roses and identified genes in the carbohydrate pathway during acclimation and deacclimation. A field experiment with four rose cultivars belonging to different USDA plant hardiness zones was set up in Melle, Belgium (51° 0' N, 3° 48' E). The more cold-hardy cultivars ('Dagmar Hastrup' and 'John Cabot') reached their lowest LT50 value in December, indicating a rapid acclimation after the first occurrence of frost. Less cold-hardy cultivars ('Abraham Darby' and 'Chandos Beauty') reached their lowest LT50 in January/February when exposed to prolonged freezing temperatures. A cell dehydration pattern was found in the less cold-hardy cultivars 'Abraham Darby' and 'Chandos Beauty'. The expression of dehydrins (RhDHN5 and RhDNH6) was up-regulated during November-January. Carbohydrate metabolism is highly involved in cold acclimation in roses. Starch decreased from November towards January in all four cultivars and the hydrolysis of starch by the ß-amylolytic pathway (BAM, DPE2) was identified in 'Dagmar Hastrup' from November to January. Oligosaccharides correlated with cold hardiness in three cultivars although no significant upregulation in RhMIPS and RhRS6, key genes in their biosynthesis, was found. Higher sucrose levels were found during acclimation in hardy cultivars, although transcript levels of RhINV2 was more prominent in 'Chandos Beauty'.


Assuntos
Metabolismo dos Carboidratos , Rosa/fisiologia , Metabolismo dos Carboidratos/genética , Metabolismo dos Carboidratos/fisiologia , Temperatura Baixa , Resposta ao Choque Frio , Genes de Plantas/genética , Genes de Plantas/fisiologia , Reação em Cadeia da Polimerase , Rosa/genética , Rosa/metabolismo , Estações do Ano , Especificidade da Espécie , Transcriptoma
18.
J Sports Med Phys Fitness ; 59(6): 1018-1025, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29991217

RESUMO

BACKGROUND: Boxers need to consider energy metabolism during rapid weight loss (RWL) followed by rapid weight regain. We examined the effects of RWL and a 3-h acute weight recovery on energy expenditure, carbohydrate oxidation, and fat oxidation in boxing athletes. METHODS: The analysis was based on the data of seven healthy young male athletes who underwent rapid weight loss followed by acute weight recovery. Energy expenditure was evaluated at three time points: one week prior to the acute weight loss (baseline); after the 1-week weight loss period; after a 3-h acute weight recovery period. This three-component model was used to estimate body composition. Sleeping metabolic rate and diet-induced thermogenesis (DIT) were measured in an indirect calorimetry room over a 17-h period. After an overnight fast, a prescribed meal was provided and the DIT was measured over a 3-h period. This was followed by a three-step treadmill running protocol. RESULTS: Weight loss produced a significant decrease in fat mass, fat free mass, and body mass, with recovery of body mass within 3 h (1.7±0.3 kg). Postprandial carbohydrate oxidation was significantly lower during the recovery period than at baseline, while fat oxidation was higher, although there was no change in the DIT. CONCLUSIONS: RWL, followed by a short-term of acute weight recovery, produces an increase in fat oxidation and a decrease in carbohydrate oxidation, with the increase in fat oxidation being maintained through an overnight sleep period, as well as in the postprandial and exercise periods.


Assuntos
Boxe/fisiologia , Metabolismo dos Carboidratos/fisiologia , Metabolismo Energético/fisiologia , Perda de Peso/fisiologia , Adulto , Composição Corporal , Humanos , Masculino , Oxirredução , Período Pós-Prandial/fisiologia , Termogênese , Fatores de Tempo , Adulto Jovem
19.
Am J Physiol Renal Physiol ; 316(3): F473-F480, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30565998

RESUMO

Fructose consumption has increased because of widespread use of high-fructose corn syrup by the food industry. Renal proximal tubules are thought to reabsorb fructose. However, fructose reabsorption (Jfructose) by proximal tubules has not yet been directly demonstrated, nor the effects of dietary fructose on Jfructose. This segment expresses Na+- and glucose-linked transporters (SGLTs) 1, 2, 4, and 5 and glucose transporters (GLUTs) 2 and 5. SGLT4 and -5 transport fructose, but SGLT1 and -2 do not. Knocking out SGLT5 increases urinary fructose excretion. We hypothesize that Jfructose in the S2 portion of the proximal tubule is mediated by luminal entry via SGLT4/5 and basolateral exit by GLUT2 and that it is enhanced by a fructose-enriched diet. We measured Jfructose by proximal straight tubules from rats consuming either tap water (Controls) or 20% fructose (FRU). Basal Jfructose in Controls was 14.1 ± 1.5 pmol·mm-1·min-1. SGLT inhibition with phlorizin reduced Jfructose to 4.9 ± 1.4 pmol·mm-1·min-1 ( P < 0.008), whereas removal of Na+ diminished Jfructose by 86 ± 5% ( P < 0.0001). A fructose-enriched diet increased Jfructose from 12.8 ± 2.5 to 19.3 ± 0.5 pmol·mm-1·min-1, a 51% increase ( P < 0.03). Using immunofluorescence, we detected luminal SGLT4 and SGLT5 and basolateral GLUT2; GLUT5 was undetectable. The expression of apical transporters SGLT4 and SGLT5 was higher in FRU than in Controls [137 ± 10% ( P < 0.01) and 38 ± 14% ( P < 0.04), respectively]. GLUT2 was also elevated by 88 ± 27% ( P < 0.02) in FRU. We conclude that Jfructose by proximal tubules occurs primarily via Na+-linked cotransport processes, and a fructose-enriched diet enhances reabsorption. Transport across luminal and basolateral membranes is likely mediated by SGLT4/5 and GLUT2, respectively.


Assuntos
Metabolismo dos Carboidratos/fisiologia , Carboidratos da Dieta/administração & dosagem , Frutose/administração & dosagem , Transportador de Glucose Tipo 2/metabolismo , Túbulos Renais Proximais/metabolismo , Proteínas de Transporte de Sódio-Glucose/metabolismo , Administração Oral , Animais , Metabolismo dos Carboidratos/efeitos dos fármacos , Transportador de Glucose Tipo 2/genética , Túbulos Renais Proximais/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley , Proteínas de Transporte de Sódio-Glucose/genética
20.
Molecules ; 24(1)2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30577556

RESUMO

Synthetic insecticides are still widely used in plant protection. The main target for their action is the nervous system, in which the cholinergic system plays a vital role. Currently available insecticides have low selectivity and act on the cholinergic systems of invertebrates and vertebrates. Acetylcholine, a cholinergic system neurotransmitter, acts on cells by two types of receptors: nicotinic and muscarinic. In mammals, the role of muscarinic acetylcholine receptors (mAChRs) is quite well-known but in insects, is still not enough. Based on data indicating that the muscarinic cholinergic system strongly affects mammalian metabolism, we investigated if it similarly occurs in insects. We investigated the influence of agonists (acetylcholine, carbachol, and pilocarpine) and antagonists (tropane alkaloids: atropine and scopolamine) of mAChRs on the level of selected metabolites in Tenebrio molitor beetle trophic tissues. We analyzed the glycogen content in the fat body and midgut, the total free sugar concentration in the hemolymph and the lipid amount in the fat body. Moreover, we analyzed the levels of insulin-like peptides in the hemolymph. The tested compounds significantly influenced the mentioned parameters. They increased the glycogen content in the fat body and midgut but decreased the concentration of free sugars in the hemolymph. The observed effects were tissue-specific, and were also time- and dose-dependent. We used nonligated and neck-ligated larvae (to eliminate the influence of head factors on tissue metabolism) to determine whether the observed changes are the result of direct or indirect impacts on tissues. The obtained data suggest that the cholinergic system affects the fat body and midgut indirectly and directly and a pleiotropic role for mAChRs exists in the regulation of energy metabolism in insects. Moreover, tested compounds significantly affected the level of insulin-like peptides in hemolymph. Our studies for the first time showed that mAChRs are involved in regulation of insect metabolism of trophic tissues, and act on them directly and indirectly. Improved knowledge about insect cholinergic system may help in searching more selective and environment-friendly solutions in pest management.


Assuntos
Besouros/metabolismo , Tenebrio/química , Acetilcolina/metabolismo , Animais , Atropina/metabolismo , Metabolismo dos Carboidratos/fisiologia , Glicogênio/metabolismo , Hemolinfa/metabolismo , Receptores Muscarínicos/metabolismo
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