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Extracellular synthesis of functional cyclodextrins (CDs) as intermediates of starch assimilation is a convenient microbial adaptation to sequester substrates, increase the half-life of the carbon source, carry bioactive compounds, and alleviate chemical toxicity through the formation of CD-guest complexes. Bacteria encoding the four steps of the carbohydrate metabolism pathway via cyclodextrins (CM-CD) actively internalize CDs across the microbial membrane via a putative type I ATP-dependent ABC sugar importer system, MdxEFG-(X/MsmX). While the first step of the CM-CD pathway encompasses extracellular starch-active cyclomaltodextrin glucanotransferases (CGTases) to synthesize linear dextrins and CDs, it is the ABC importer system in the second step that is the critical factor in determining which molecules from the CGTase activity will be internalized by the cell. Here, structure-function relationship studies of the cyclo/maltodextrin-binding protein MdxE of the MdxEFG-MsmX importer system from Thermoanaerobacter mathranii subsp. mathranii A3 are presented. Calorimetric and fluorescence studies of recombinant MdxE using linear dextrins and CDs showed that although MdxE binds linear dextrins and CDs with high affinity, the open-to-closed conformational change is solely observed after α- and ß-CD binding, suggesting that the CM-CD pathway from Thermoanaerobacterales is exclusive for cellular internalization of these molecules. Structural analysis of MdxE coupled with docking simulations showed an overall architecture typically found in sugar-binding proteins (SBPs) that comprised two N- and C-domains linked by three small hinge regions, including the conserved aromatic triad Tyr193/Trp269/Trp378 in the C-domain and Phe87 in the N-domain involved in CD recognition and stabilization. Structural bioinformatic analysis of the entire MdxFG-MsmX importer system provided further insights into the binding, internalization, and delivery mechanisms of CDs. Hence, while the MdxE-CD complex couples to the permease subunits MdxFG to deliver the CD into the transmembrane channel, the dimerization of the cytoplasmatic promiscuous ATPase MsmX triggers active transport into the cytoplasm. This research provides the first results on a novel thermofunctional SBP and its role in the internalization of CDs in extremely thermophilic bacteria.

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Background: Obesity poses a major risk for cardiovascular diseases, while it is almost a consensus that intra-abdominal adiposity has a more deleterious effect for metabolic syndrome. In this sense, it is speculated that lipectomy or liposuction would be metabolically harmful, as it changes the abdominal-superficial adipose tissue ratio. However, the literature has shown conflicting evidence. Methods: In order to evaluate the possibility of metabolism alteration resulting from body coutouring surgery, a prospective cohort was implemented with 35 patients who underwent abdominoplasty, including some with a history of massive weight loss. Fasting blood glucose, fasting plasma insulin, triglycerides, total cholesterol and fractions were requested preoperatively and in the third postoperative month. The groups were also compared with each other. Results: No statistically significant variation between the exams collected in the preoperative period and those collected after abdominoplasty was found. There was a statistically significant difference in LDL (low-density lipoprotein; p = 0.033) and non-HDL (non-high-density lipoprotein) cholesterol (p = 0.020) between the two control tests of the groups surveyed. There were also differences in comorbidities (p = 0.006) and complications (p <0.001) between the groups. Conclusions: Abdominoplasty was not able of changing tests that assess glycemic and lipid metabolism three months after the operation. Our attention was drawn to the fact that patients who had massive weight loss had better control of LDL cholesterol (p = 0.033) and non-HDL cholesterol (p = 0.020), despite having higher weight and body mass index (p <0.001).

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Ocypode quadrata, a Ghost crab species found along the western Atlantic coast, is considered a bioindicator of anthropogenic impact on sandy beaches. Ghost Crabbing, a touristic activity in which ghost crabs are chased just for fun, is a potentially threatening activity for this crab. In crustaceans, metabolites such as glucose and lactate, and the gene expression of crustacean hyperglycemic hormone (CHH) and heat shock proteins (HSPs) increase when the animals are exposed to several types of stress, including alterations in temperature, salinity, or exposure to xenobiotics. This work was developed to identify if being chased by humans would affect these markers of stress in this species of crab. The effects of chasing stress on hemolymph and tissue metabolites and the gene expression levels of CHH and HSP70 were investigated. The levels of lactate in the hemolymph of stressed crabs were six times higher than those of control crabs immediately after chasing and decreased progressively during recovery, indicating an active anaerobic metabolism during the stress. On the contrary, glucose levels in the hemolymph of the stressed crabs increased progressively from 30 to 60 min after chasing, indicating an inverse correlation between glucose and lactate and the conversion of lactate to glucose by gluconeogenesis. In stressed crabs, the levels of triglycerides in the hemolymph decreased 30 min after chasing, while the opposite tended to occur in the hepatopancreas, indicating that during recovery, the crabs use triglycerides as energy source to sustain aerobic metabolism. Finally, this study demonstrates that ghost crabs are stressed by minimum human contact and that "ghost crabbing" must not be encouraged as a tourist activity.

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Human herpesviruses are enveloped viruses with double-stranded linear DNA genomes highly prevalent in the human population. These viruses are subdivided into three subfamilies, namely alphaherpesvirinae (herpes simplex virus type 1, HSV-1; herpes simplex virus type 2, HSV-2; and varicella-zoster virus, VZV), betaherpesvirinae (human cytomegalovirus, HCMV; human herpesvirus 6, HHV-6; and human herpesvirus 7, HHV-7) and gammaherpesvirinae (Epstein-Barr virus, EBV; and Kaposi's sarcoma-associated herpesvirus, KSHV). Besides encoding numerous molecular determinants to evade the host antiviral responses, these viruses also modulate cellular metabolic processes to promote their replication. Here, we review and discuss existing studies describing an interplay between carbohydrate metabolism and the replication cycle of herpesviruses, altogether highlighting potentially new molecular targets based on these interactions that could be used to block herpesvirus infections.

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Green turtles, Chelonia mydas, have been included in biomonitoring efforts given its status as an endangered species. Many studies, however, rely on samples from stranded animals, raising the question of how death affects important biochemical and molecular biomarkers. The goal of this study was to investigate post mortem fluctuations in the antioxidant response and metabolism of carbohydrates in the liver of C. mydas. Liver samples were obtained from six green turtles which were submitted to rehabilitation and euthanized due to the impossibility of recovery. Samples were collected immediately after death (t = 0) and at various time intervals (1, 2, 3, 4, 5, 6, 12, 18 and 24 h post mortem), frozen in liquid nitrogen and stored at -80 °C. The activities of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PDH) were analyzed, as were the levels of lipid peroxidation, glycogen concentration, RNA integrity (RNA IQ) and transcript levels of carbonic anhydrase and pyruvate carboxylase genes. Comparison between post mortem intervals showed a temporal stability for all the biomarkers evaluated, suggesting that changes in biochemical and molecular parameters following green turtle death are not immediate, and metabolism may remain somewhat unaltered up to 24 h after death. Such stability may be associated with the overall lower metabolism of turtles, especially under an oxygen deprivation scenario such as organismal death. Overall, this study supports the use of biomarkers in sea turtles sampled within a period of 24 h post mortem for biomonitoring purposes, though it is recommended that post mortem fluctuations of particular biomarkers be evaluated prior to their application, given that proteins may show varying degrees of susceptibility to proteolysis.

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Lytic polysaccharide monooxygenases (LPMOs) are oxidative enzymes found in viruses, archaea, and bacteria as well as eukaryotes, such as fungi, algae and insects, actively contributing to the degradation of different polysaccharides. In Aspergillus nidulans, LPMOs from family AA9 (AnLPMO9s), along with an AA3 cellobiose dehydrogenase (AnCDH1), are cosecreted upon growth on crystalline cellulose and lignocellulosic substrates, indicating their role in the degradation of plant cell wall components. Functional analysis revealed that three target LPMO9s (AnLPMO9C, AnLPMO9F and AnLPMO9G) correspond to cellulose-active enzymes with distinct regioselectivity and activity on cellulose with different proportions of crystalline and amorphous regions. AnLPMO9s deletion and overexpression studies corroborate functional data. The abundantly secreted AnLPMO9F is a major component of the extracellular cellulolytic system, while AnLPMO9G was less abundant and constantly secreted, and acts preferentially on crystalline regions of cellulose, uniquely displaying activity on highly crystalline algae cellulose. Single or double deletion of AnLPMO9s resulted in about 25% reduction in fungal growth on sugarcane straw but not on Avicel, demonstrating the contribution of LPMO9s for the saprophytic fungal lifestyle relies on the degradation of complex lignocellulosic substrates. Although the deletion of AnCDH1 slightly reduced the cellulolytic activity, it did not affect fungal growth indicating the existence of alternative electron donors to LPMOs. Additionally, double or triple knockouts of these enzymes had no accumulative deleterious effect on the cellulolytic activity nor on fungal growth, regardless of the deleted gene. Overexpression of AnLPMO9s in a cellulose-induced secretome background confirmed the importance and applicability of AnLPMO9G to improve lignocellulose saccharification. IMPORTANCE Fungal lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that boost plant biomass degradation in combination with glycoside hydrolases. Secretion of LPMO9s arsenal by Aspergillus nidulans is influenced by the substrate and time of induction. These findings along with the biochemical characterization of novel fungal LPMO9s have implications on our understanding of their concerted action, allowing rational engineering of fungal strains for biotechnological applications such as plant biomass degradation. Additionally, the role of oxidative players in fungal growth on plant biomass was evaluated by deletion and overexpression experiments using a model fungal system.

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A deficit of estrogen is associated with energy substrate imbalance, raising the risk of metabolic diseases. Physical training (PT) is a potent metabolic regulator through oxidation and storage of substrates transported by GLUT4 and FAT CD36 in skeletal muscle. However, little is known about the effects of PT on these carriers in an estrogen-deficit scenario. Thus, the aim of this study was to determine the influence of 12 weeks of PT on metabolic variables and GLUT4 and FAT CD36 expression in the skeletal muscle of animals energetically impaired by ovariectomy (OVX). The trained animals swam 30 min/day, 5 days/week, at 80% of the critical load intensity. Spontaneous physical activity was measured biweekly. After training, FAT CD36 and GLUT4 expressions were quantified by immunofluorescence in the soleus, as well as muscular glycogen and triglyceride of the soleus, gluteus maximus and gastrocnemius. OVX significantly reduced FAT CD36, GLUT4 and spontaneous physical activity (p < 0.01), while PT significantly increased FAT CD36, GLUT4 and spontaneous physical activity (p < 0.01). PT increased soleus glycogen, and OVX decreased muscular triglyceride of gluteus maximus. Therefore, OVX can cause energy disarray through reduction in GLUT4 and FAT CD36 and their muscle substrates and PT prevented these metabolic consequences, masking ovarian estrogen's absence.

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Predictions about global warming have raised interest in assessing whether ectothermic organisms will be able to adapt to these changes. Understanding the physiological mechanisms and metabolic adjustment capacity of fish subjected to heat stress can provide subsidies that may contribute to decision-making in relation to ecosystems and organisms subjected to global climate change. This study investigated the antioxidant defence system and energy metabolism of carbohydrate and protein responses in the gill, liver and kidney tissues of Psalidodon bifasciatus (Garavello & Sampaio 2010), a Brazilian freshwater fish used in aquaculture and in biological studies, following exposure to heat shock at 31°C for 2, 6, 12, 24 and 48 h. The fish presented signs of stress in all tissues tested, as evidenced by increased lipid peroxidation concentration at 2 h and phosphofructokinase, hexokinase and malate dehydrogenase activity at 48 h in the gills; increased glutathione-S-transferase activity at 12 h, citrate synthase activity at 24 h and concentration of reduced glutathione (GSH) concentration at 12 and 48 h in the liver; and through increased activity of superoxide dismutase at 48 h, glutathione reductase at 24 h, glucose-6-phosphate dehydrogenase at 48 h and concentration of GSH at 24 h in the kidney. In the kidneys, changes in the antioxidant system were more prominent, whereas in the gills, there were greater changes in the carbohydrate metabolism. These results indicated the importance of glycolysis and aerobic metabolism in the gills, aerobic metabolism in the liver and pentose-phosphate pathway in the kidneys during homeostasis. The biomarker response was tissue specific, with the greatest number of biomarkers altered in the gills, followed by those in the kidneys and liver.

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Intracellular parasites such as Trypanosoma cruzi need to acquire valuable carbon sources from the host cell to replicate. Here, we investigated the energetic metabolism of T. cruzi during metacyclogenesis through the determination of enzymatic activities and quantification by HPLC of glycolytic and Krebs cycle short-chain carboxylic acids. Altered concentrations in pyruvate, acetate, succinate, and glycerate were measured during the growth of epimastigote in the complex medium BHI and their differentiation to trypomastigotes in the chemically defined medium, TAU3AAG. These alterations should represent significant differential metabolic modifications utilized by either form to generate energy. This paper is the first work dealing with the intracellular organic acid concentration measurement in T. cruzi parasites. Although it confirms the previous assumption of the importance of carbohydrate metabolism, it yields an essential improvement in T. cruzi metabolism knowledge.

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Ruminants are foregut fermenters that have the remarkable ability of converting plant polymers that are indigestible to humans into assimilable comestibles like meat and milk, which are cornerstones of human nutrition. Ruminants establish a symbiotic relationship with their microbiome, and the latter is the workhorse of carbohydrate fermentation. On the other hand, during carbohydrate fermentation, synthesis of propionate sequesters H, thus reducing its availability for the ultimate production of methane (CH4) by methanogenic archaea. Biochemically, methane is the simplest alkane and represents a downturn in energetic efficiency in ruminants; environmentally, it constitutes a potent greenhouse gas that negatively affects climate change. Prevotella is a very versatile microbe capable of processing a wide range of proteins and polysaccharides, and one of its fermentation products is propionate, a trait that appears conspicuous in P. ruminicola strain 23. Since propionate, but not acetate or butyrate, constitutes an H sink, propionate-producing microbes have the potential to reduce methane production. Accordingly, numerous studies suggest that members of the genus Prevotella have the ability to divert the hydrogen flow in glycolysis away from methanogenesis and in favor of propionic acid production. Intended for a broad audience in microbiology, our review summarizes the biochemistry of carbohydrate fermentation and subsequently discusses the evidence supporting the essential role of Prevotella in lignocellulose processing and its association with reduced methane emissions. We hope this article will serve as an introduction to novice Prevotella researchers and as an update to others more conversant with the topic.

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Background: Low metabolic flexibility (MetF) may be an underlying factor for metabolic health impairment. Individuals with low MetF are thus expected to have worse metabolic health than subjects with high MetF. Therefore, we aimed to compare metabolic health in individuals with contrasting MetF to an oral glucose tolerance test (OGTT). Methods: In individuals with excess body weight, we measured MetF as the change in respiratory quotient (RQ) from fasting to 1 h after ingestion of a 75-g glucose load (i.e., OGTT). Individuals were then grouped into low and high MetF (Low-MetF n = 12; High-MetF n = 13). The groups had similar body mass index, body fat, sex, age, and maximum oxygen uptake. Metabolic health markers (clinical markers, insulin sensitivity/resistance, abdominal fat, and intrahepatic fat) were compared between groups. Results: Fasting glucose, triglycerides (TG), and high-density lipoprotein (HDL) were similar between groups. So were insulin sensitivity/resistance, visceral, and intrahepatic fat. Nevertheless, High-MetF individuals had higher diastolic blood pressure, a larger drop in TG concentration during the OGTT, and a borderline significant (P = 0.05) higher Subcutaneous Adipose Tissue (SAT). Further, compared to Low-MetF, High-MetF individuals had an about 2-fold steeper slope for the relationship between SAT and fat mass index. Conclusion: Individuals with contrasting MetF to an OGTT had similar metabolic health. Yet High-MetF appears related to enhanced circulating TG clearance and enlarged subcutaneous fat.

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BACKGROUND AND AIM: Metabolic disturbances are known for their increasing epidemiological importance. Ilex paraguariensis presents a potential option for mitigating lipid metabolism imbalance. However, most of the literature to date has not considered sex bias. This study aimed to evaluate the effect of Ilex paraguariensis on the metabolism of different adipose tissue depots in males and females. EXPERIMENTAL PROCEDURE: After ovariectomy, female Wistar rats received daily treatment with the extract (1 g/kg) for forty-five days. Biochemical serum parameters and tissue metabolism were evaluated. Oxidation, lipogenesis and lipolysis were evaluated in brown, white visceral, retroperitoneal and gonadal adipose tissues. RESULTS AND CONCLUSION: The results showed that treatment with the extract led to a reduced weight gain in ovariectomised females in comparison to control. The triglyceride concentration was decreased in males. Glucose oxidation and lipid synthesis in visceral and retroperitoneal adipose tissues were restored in ovariectomised females after treatment. The response to epinephrine decreased in visceral adipose tissue of control males; however, lipolysis in females did not respond to ovariectomy or treatment. These findings highlight the enormous potential effects of I. paraguariensis on lipid metabolism, modulating lipogenic pathways in females and lipolytic pathways in males. Furthermore, the sex approach applied in this study contributes to more effective screening of the effects of I. paraguariensis bioactive substances.

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Considering that post-menopausal women and ovariectomized rodents develop obesity associated with increased visceral fat, this study was developed to investigate if liraglutide, a glucagon-like peptide 1 (GLP1) analogue, could improve the metabolism of estrogen (E2) deficient females. Wistar rats were ovariectomized (OVX), and subdivided in four groups: sham saline, sham liraglutide, OVX saline, and OVX liraglutide. After sixty days, metabolic parameters of blood, heart, liver, brown (BAT) and white adipose tissue (WAT) visceral depots, and, heart oxidative homeostasis, were evaluated. Castration increased the animals' body weight, the relative weight of the WAT depots, hepatic triglycerides and cardiac glycogen content. Liraglutide treatment reversed these effects, decreased WAT depots weight and increased glucose oxidation and lipogenesis in BAT and WAT. In addition, liraglutide enhanced adrenalin (A) lipolytic effect. These results indicate that liraglutide may be a promising treatment to restore lipid homeostasis and prevent weight gain associated with E2 deficiency.

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ABSTRACT Introduction Blood biomarkers are measurable metabolic products that allow objective monitoring of the training process, and their analysis provides an opportunity to improve athletic performance. Objective To evaluate blood lactate concentrations in a group of the Valle League weightlifting athletes as a tool to determine the effects of training and its direct relationship to performance during competition. Methods This is an observational cross-sectional study. Lactate levels of 32 weightlifting athletes belonging to the Valle Weightlifting League were evaluated. Blood samples were taken from the ear lobe to quantify the lactate concentration, using a Scout Lactate analyzer. Samples were taken before and after a high intensity training section consisting of four maximum repetition (MR) sports gestures, in which 5 series and 15 repetitions were performed for each sports gesture, with a rest period of 40 seconds between each exercise. The software program SPSS, version 25, was used to determine the lactate concentrations. Results An average lactate concentration 22.46 mg/dL was obtained for the athletes at rest, and an average of 98.30 mg/dL in the final lactate concentration, after high intensity exercise. Significant differences were found between the initial and final lactate concentrations. Conclusion Lactate concentration increases with physical activity; it varies from one individual to another; and it can be used as a biomarker of intensity of physical activity in the field of sports. Level of evidence; II type of study: Prognostic Studies Investigating the Effect of a Patient Characteristic on a disease outcome.

RESUMO Introdução Os biomarcadores sanguíneos são produtos metabólicos mensuráveis que permitem a monitorização objetiva do processo de treino, e sua análise é uma oportunidade para melhorar o desempenho atlético. Objetivos Avaliar as concentrações de lactato no sangue de um grupo de atletas de halterofilismo da Liga Valle como ferramenta para determinar os efeitos do treino e sua relação direta com o desempenho durante a competição. Métodos Este é um estudo transversal e observacional. Foram avaliados os níveis de lactato em 32 atletas da Liga de Halterofilismo Valle. A amostra de sangue foi retirada do lóbulo da orelha com o intuito de quantificar a concentração de lactato com o analisador Scout Lactate. As amostras foram colhidas antes e depois de uma seção de treino de alta intensidade, que consistiu em quatro gestos esportivos de repetição máxima (RM), nos quais foram realizadas 5 séries e 15 repetições para cada gesto esportivo, com um período de repouso de 40 segundos entre cada exercício. O software SPSS, versão 25 foi usado para determinar as concentrações de lactato. Resultados A concentração média de lactato nos atletas em repouso foi 22,46 mg/dl e a concentração média final foi de 98,30 mg/dl depois de exercício de alta intensidade. Foram encontradas diferenças significativas ao comparar a concentração inicial com a concentração final de lactato. Conclusões A concentração de lactato aumenta com a realização da atividade física, é variável de um indivíduo para outro e pode ser usada como biomarcador de intensidade da atividade física na área dos esportes. Nível de Evidência II; Estudos prognósticos - Investigação do efeito de característica de um paciente sobre o desfecho da doença.

RESUMEN Introducción Los biomarcadores sanguíneos son productos metabólicos mensurables que permiten la monitorización objetiva del proceso de entrenamiento, y su análisis es una oportunidad para mejorar el desempeño atlético. Objetivos Evaluar las concentraciones de lactato en la sangre de un grupo de atletas de halterofilia de la Liga Valle como herramienta para determinar los efectos del entrenamiento y su relación directa con el desempeño durante la competición. Métodos Este es un estudio transversal y observacional. Fueron evaluados los niveles de lactato en 32 atletas de la Liga de Halterofilia Valle. La muestra de sangre fue retirada del lóbulo de la oreja con el objetivo de cuantificar la concentración de lactato con el analizador Scout Lactate. Las muestras fueron tomadas antes y después de una sección de entrenamiento de alta intensidad, que consistió en cuatro gestos deportivos de repetición máxima (RM), en los que se realizaron 5 series y 15 repeticiones para cada gesto deportivo, con un período de descanso de 40 segundos entre cada ejercicio. El software SPSS versión 25 fue usado para determinar las concentraciones de lactato. Resultados La concentración promedio de lactato en los atletas en reposo fue 22,46 mg/dl y la concentración promedio final fue de 98,30 mg/dl después del ejercicio de alta intensidad. Fueron encontradas diferencias significativas al comparar la concentración inicial con la concentración final de lactato. Conclusiones La concentración de lactato aumenta con la realización de actividad física, es variable de un individuo para otro, y puede ser usada como biomarcador de intensidad de la actividad física en el área de los deportes. Nivel de evidencia II; Estudios pronósticos - Investigación del efecto de característica de un paciente sobre el resultado de la enfermedad

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Over the past decades, several advances in cancer cell biology have led to relevant details about a phenomenon called the 'Warburg effect'. Currently, it has been accepted that the Warburg effect is not compatible with all cancer cells, and thus the process of aerobic glycolysis is now challenged by the knowledge of a large number of cells presenting mitochondrial function. The energy metabolism of cancer cells is focused on the bioenergetic and biosynthetic pathways in order to meet the requirements of rapid proliferation. Changes in the metabolism of carbohydrates, amino acids and lipids have already been reported for cancer cells and this might play an important role in cancer progression. To the best of our knowledge, these changes are mainly attributed to genetic reprogramming which leads to the transformation of a healthy into a cancerous cell. Indeed, several enzymes that are highly relevant for cellular energy are targets of oncogenes (e.g. PI3K, HIF1, and Myc) and tumor suppressor proteins (e.g. p53). As a consequence of extensive studies on cancer cell metabolism, some new therapeutic strategies have appeared that aim to interrupt the aberrant metabolism, in addition to influencing genetic reprogramming in cancer cells. In this review, we present an overview of cancer cell metabolism (carbohydrate, amino acid, and lipid), and also describe oncogenes and tumor suppressors that directly affect the metabolism. We also discuss some of the potential therapeutic candidates which have been designed to target and disrupt the main driving forces associated with cancer cell metabolism and proliferation.

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Amoebiasis is a parasitic infection of the human large intestine caused by Entamoeba histolytica; this disease mainly affects people from developing countries. To survive, this primitive protozoan has a high demand for iron, and it uses host iron proteins upon invasion. Transferrin (Tf) is a plasma iron-binding protein that transports and delivers iron to all cells. Iron-loaded Tf (holoTf) in humans can support the proliferation of amoebae in vitro by binding to an amoebic TfR (EhTfR), and amoebae endocytose it inside clathrin-coated vesicles. In this study, it was found that EhTfR phosphorylation is required for human holoTf endocytosis by E. histolytica. Once this complex is endocytosed, human holoTf could be degraded with a nutritional purpose by cysteine proteases. HoloTf endocytosis initiates the activation of the mitogen-activated protein kinases (MAPKs) and focal adhesion kinase (FAK) pathways, which induce cell proliferation with phosphoinositide 3-kinase (PI-3 K) and Ca2+ involvement. In the first minutes after holoTf is endocytosed, several proteins are phosphorylated including transketolase, enolase, L-myo-inositol-1-phosphate synthase and phosphoglucomutase, which control carbohydrate metabolism, and heat shock protein-70. The study of these proteins and their signal transduction pathways could be useful for developing future therapies.

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The burrowing crab Neohelice granulata is a key omnivorous species in intertidal areas along the southwestern Atlantic from southern Brazil to northern Argentinean Patagonia. This crab is adapted to starvation and can endure natural periods of food deprivation. The metabolic adjustments during starvation depend on the type of diet the crabs were fed previously. Since eyestalk-crustacean hyperglycemic hormone (CHH) is the principal regulator of glucose homeostasis in decapods, we investigated whether CHH transcription was affected by diet composition and starvation. Crabs were maintained in the laboratory for two weeks and subsequently divided in two groups. One received a high carbohydrate (HC) diet, and the other was fed a high protein (HP) diet. After this period, they were starved for four weeks. The full-length cDNA sequence of N. granulata CHH was determined and aligned with CHH sequences of other crabs. Levels of circulating glucose and glycogen were higher in the hepatopancreas and muscle of the HC-fed group and decreased after starvation. Glucose and glycogen concentrations were not altered by starvation in the HP group. Triglyceride levels within the hemolymph were not altered by diet or starvation. However, triglycerides concentration was higher in the hepatopancreas of HC compared to HP-fed group. Long-term starvation and diet composition did not affect CHH transcription.

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The objective of this study is to delineate the cellular adhesion molecule (CAM) profile and plasminogen activator inhibitor type 1 (PAI-1), and their association with metabolic syndrome (MetS) and carbohydrate metabolism biomarkers in psoriasis patients with mild and moderate severity. Sixty-seven patients with psoriasis as well as 102 healthy subjects were recruited. Insulin and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), but not glucose, were significantly higher in psoriasis than in controls. Psoriasis was characterized by increased plasma levels of platelet endothelial cell adhesion molecule 1 (PECAM-1), vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), E-selectin, and PAI-1 as compared with controls. Psoriasis diagnosis could explain 59.0% of CAM and PAI-1 variance, with a particularly strong impact on E-selectin (45.6%), VCAM-1 (32.7%), and PAI-1 (24.8%). Subjects with MetS showed significantly higher E-selectin and PAI-1 than those without MetS. Using VCAM-1, E-selectin, PAI-1 (all positively), and P-selectin (inversely) in a binary regression equation, it was found that 87.6% of all patients were correctly classified with a sensitivity of 92.5% and a specificity of 84.3%. CAM and PAI-1 were correlated with carbohydrate metabolism biomarkers (glucose, insulin, and HOMA-IR). In conclusion, CAM levels are associated with psoriasis diagnosis and MetS may influence E-selectin and PAI-1 concentrations. More studies are needed to verify the causality among these factors, as well as their relation to the different degrees of disease severity.

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Resumen Introducción: La metabolómica permite estudiar la resistencia a insulina (RI), un factor de riesgo de pre-diabetes y diabetes. Quantose IR TM es el único test que mide la RI mediante la abrazadera hiperinsulinémica euglicémica. Objetivo: Se comprobó la eficacia de un test metabolómico en la detección de marcadores de RI en población infantil. Materiales ymétodos: Once niños, de edad 8,54±3,53 años y con factores de riesgo de diabetes, fueron reclutados del Hospital El Escorial. Se estableció como criterio diagnóstico para la prediabetes el estándar de la Asociación Americana de Diabetes (ADA) (HbA1C 5,7-6,4% y glucosa basal 100-125mg/dl). Se compararon las analíticas de sangre con la prueba de Quantose IR TM , estudiando el perfil del metaboloma relacionado con la RI (ácido alfa-hidroxibutírico, ácido oleico, linoleo-glicerofosfocolina e insulina). Su análisis generó una puntuación Quantose © (escala 0-100), siendo >63 RI. Resultados: Ningún sujeto cumplió el criterio de la ADA para prediabetes: HbA1C fue 5,3±0,18 % y glucosa 86,6±5,6 mg/dl. Por el contrario, 10 sujetos cumplieron criterios del test Quantose IR TM para la RI (score: 78,09 ± 9,24 (>63)). Conclusiones: El test Quantose IR TM mide el porcentaje de hemoglobina unida a glucosa dentro de los glóbulos rojos. Permite prever el riesgo de diabetes, y tomar medidas preventivas.

Abstract Introduction: Metabolomics enables the study of insulin resistance (IR), a risk factor for pre-diabetes and diabetes. Quantose IRTM is the only test that measures IR using the euglycemic hyperinsulinemic clamp. Objective: The effectiveness of a metabolomic test for the detection of RI markers in a child population was verified. Materials and methods: Eleven children aged 8.54 ± 3.53 years with diabetes risk factors were recruited from the El Escorial Hospital. The American Diabetes Association (ADA) Standards (5,7-6,4% HbA1C and 100-125 mg/dl basal glucose) were established as diagnostic criteria for prediabetes. Blood tests were compared to the Quantose IRTM assay studying the metabolomic profile related to IR (alpha-hydroxybutyric acid, oleic acid, linoleo-glycerophosphocoline and insulin). This analysis generated a Quantose © score of IR > 63. Results: None of the subjects met the ADA criteria for prediabetes: HbA1C=5,3±0,18 and glucose=86,6± 5,6 mg/dl. On the contrary, 10 subjects met the Quantose IRTM test criterion for IR (score: 78,09 ± 9,24 (>63)). Conclusions: The Quantose IRTM test measures the percentage of glucose bound hemoglobin within red blood cells. This assay makes it possible to predict diabetes risk and take preventive measures.

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The taxonomically diverse rhizosphere microbiome contributes to plant nutrition, growth and health, including protection against soil-borne pathogens. We previously showed that breeding for Fusarium-resistance in common bean changed the rhizosphere microbiome composition and functioning. Here, we assessed the impact of Fusarium-resistance breeding in common bean on microbiome physiology. Combined with metatranscriptome data, community-level physiological profiling by Biolog EcoPlate analyses revealed that the rhizosphere microbiome of the Fusarium-resistant accession was distinctly different from that of the Fusarium-susceptible accession, with higher consumption of amino acids and amines, higher metabolism of xylanase and sialidase, and higher expression of genes associated with nitrogen, phosphorus and iron metabolism. The resistome analysis indicates higher expression of soxR, which is involved in protecting bacteria against oxidative stress induced by a pathogen invasion. These results further support our hypothesis that breeding for resistance has unintentionally shaped the assembly and activity of the rhizobacterial community toward a higher abundance of specific rhizosphere competent bacterial taxa that can provide complementary protection against fungal root infections.