Role Of Glucose Research Articles

682 Induction of keratin 1 and keratin 10 expression by topical glucose in a mouse model of atopic dermatitis and in keratinocyte culture: A possible role of glucose in skin barrier repair

682 Induction of keratin 1 and keratin 10 expression by topical glucose in a mouse model of atopic dermatitis and in keratinocyte culture: A possible role of glucose in skin barrier repair

Gastric inhibitory polypeptide receptor antagonist, SKL-14959, suppressed body weight gain on diet-induced obesity mice.

SummaryObjectiveGastric inhibitory polypeptide plays a role in glucose and lipid metabolism and is associated with obesity and insulin resistance. The objective of this study is to confirm the anti‐obesity effects of the gastric inhibitory polypeptide receptor antagonist, SKL‐14959, on diet‐induced obesity mice.MethodDiet‐induced obesity mice at 20 weeks of age were administered with or without SKL‐14959 for 96 d. Body weight and food intake were monitored throughout the experiment. Mice were sacrificed, and physiological and biochemical markers were measured, and then histochemical and gene expression analyses were also performed. In further studies, mice were orally gavaged with [14C]‐oleic acid to investigate the excursion of digested lipids.ResultsSKL‐14959 significantly suppressed weight gain without affecting food intake, decreased triacylglycerol contents in the liver and the muscle and the intensity stained with oil‐red in the liver. It also improved plasma glutamic pyruvic transaminase and 3‐hydroxybutyrate levels in addition to notably down‐regulated relative gene expression of srebf1 and dgat1 in the liver despite not altering in the adipose tissue. Furthermore, SKL‐14959 showed remarkable inhibition of lipid uptake in the adipose tissue after the oil challenge.ConclusionSKL‐14959 inhibited lipids uptake and improved lipids metabolism, results in suppression of body‐weight gain.

Bile acids are important direct and indirect regulators of the secretion of appetite- and metabolism-regulating hormones from the gut and pancreas

ObjectiveBile acids (BAs) facilitate fat absorption and may play a role in glucose and metabolism regulation, stimulating the secretion of gut hormones. The relative importance and mechanisms involved in BA-stimulated secretion of appetite and metabolism regulating hormones from the gut and pancreas is not well described and was the purpose of this study. MethodsThe effects of bile acids on the secretion of gut and pancreatic hormones was studied in rats and compared to the most well described nutritional secretagogue: glucose. The molecular mechanisms that underlie the secretion was studied by isolated perfused rat and mouse small intestine and pancreas preparations and supported by immunohistochemistry, expression analysis, and pharmacological studies. ResultsBile acids robustly stimulate secretion of not only the incretin hormones, glucose-dependent insulinotropic peptide (GIP), and glucagon-like peptide-1 (GLP-1), but also glucagon and insulin in vivo, to levels comparable to those resulting from glucose stimulation. The mechanisms of GLP-1, neurotensin, and peptide YY (PYY) secretion was secondary to intestinal absorption and depended on activation of basolateral membrane Takeda G-protein receptor 5 (TGR5) receptors on the L-cells in the following order of potency: Lithocholic acid (LCA) >Deoxycholicacid (DCA)>Chenodeoxycholicacid (CDCA)> Cholic acid (CA). Thus BAs did not stimulate secretion of GLP-1 and PYY from perfused small intestine in TGR5 KO mice but stimulated robust responses in wild type littermates. TGR5 is not expressed on α-cells or β-cells, and BAs had no direct effects on glucagon or insulin secretion from the perfused pancreas. ConclusionBAs should be considered not only as fat emulsifiers but also as important regulators of appetite- and metabolism-regulating hormones by activation of basolateral intestinal TGR5.

Divergent Role of Sphingosine 1-Phosphate in Liver Health and Disease.

Two decades ago, sphingosine 1-phosphate (S1P) was discovered as a novel bioactive molecule that regulates a variety of cellular functions. The plethora of S1P-mediated effects is due to the fact that the sphingolipid not only modulates intracellular functions but also acts as a ligand of G protein-coupled receptors after secretion into the extracellular environment. In the plasma, S1P is found in high concentrations, modulating immune cell trafficking and vascular endothelial integrity. The liver is engaged in modulating the plasma S1P content, as it produces apolipoprotein M, which is a chaperone for the S1P transport. Moreover, the liver plays a substantial role in glucose and lipid homeostasis. A dysfunction of glucose and lipid metabolism is connected with the development of liver diseases such as hepatic insulin resistance, non-alcoholic fatty liver disease, or liver fibrosis. Recent studies indicate that S1P is involved in liver pathophysiology and contributes to the development of liver diseases. In this review, the current state of knowledge about S1P and its signaling in the liver is summarized with a specific focus on the dysregulation of S1P signaling in obesity-mediated liver diseases. Thus, the modulation of S1P signaling can be considered as a potential therapeutic target for the treatment of hepatic diseases.

Influence of long-term per oral taurine treatment on activity of liver enzymes in mature rats

Taurine is sulfur-containing derivative of methionin and cysteine that plays a key role in glucose and lipid metabolism. Taurine regulates antioxidant defense system, membrane potential of mitochondria, and glycolysis. Thus, it might have a serious impact on cell metabolism in mammals. The aim of this work was to study the influence of long-term per oral taurine treatment (5, 10 and 20 mg/kg) on the antioxidant defense system, cholesterol content, activity of transaminases and lactate dehydrogenase in rat liver. To achieve that goal, mature Wistar rats (weight 140–160 g, age – 4 months) were divided in four groups – control, rats which once a day during 28 days were injected drinking water in esophagus, and three experimental groups, that were injected taurine solution in concentrations: І – 5 mg/kg, ІІ – 10 mg/kg and ІІІ – 20 mg/kg of body mass. After 28 days, rats were decapitated under light chloroform narcosis and liver mass was determined. In liver, content of cholesterol, TBA-active products and activity of antioxidant defense enzymes, transaminases, and lactate dehydrogenase were measured. Our results show that after a long-term per oral taurine treatment liver mass decreased by 27.5 % comparing to control group. Lactate dehydrogenase activity increased two times, while the activity of alanine aminotranferase and aspartate aminotransferase in mitochondrial fraction increased by 40–90 % in liver of animals of all experimental groups. Total activity of these enzymes in rat liver increased by 20–37 % in all experimental groups. Cholesterol content increased dy 32.4 % in rats of experimental group II. This may indicate intensification of liver metabolism. The content of TBA-active products in submitochondrial and mitochondrial fractions increased more than two times in rats of experimental groups II and III. The activity of superoxide dismutase in the submitochondrial fraction increased by 49.8 and 36.5 % in liver of that rats. The activation of superoxi­de dismutase and a rise in content of TBA-active products may suggest a rise of free oxygen radicals production and inability of antioxidant defense system. These results may indicate a negative influence of taurine in doses higher than 5 mg/kg, since the balance between antioxidant protection and lipid peroxidation processes was violated.

Cellular glucose metabolism is essential for the reduction of cell-impermeable water-soluble tetrazolium (WST) dyes

Water-soluble tetrazolium (WST) dyes, such as WST-1 and WST-8, are widely used in cell proliferation and anti-cell-growth drug screen assays. However, the underlying determinants for WST reduction are still largely unknown. In addition, application of tetrazolium-based assays to cellular glucose metabolism studies has not been fully explored. In the present study, we show here that WST-8 reduction is dependent on cellular glucose metabolism. In order to minimize the variance of live cell number during stimulation, we treated cells with different stimuli and performed tetrazolium-based assays within 6 hours. Withdrawal of medium glucose supply greatly attenuated WST-8 reduction but not intracellular ATP levels, while re-adding glucose reconstituted WST-8 reduction, indicating the effect was not due to cell death. The role of glucose on WST-8 reduction is specific since glutamine, fructose or galactose did not substitute for the effect of glucose on WST-8 reduction. Furthermore, inhibition of glucose transporters, intracellular glucose metabolic enzymes or EGFR-PI3K-Akt signaling also attenuated WST-8 reduction. In an attempt to screen inhibitors targeting cellular glucose metabolism from hyperglycemia-associated drugs, it turned out that HIV protease inhibitor, ritonavir, could largely block WST-8 reduction, but not cellular ATP level. Interestingly, ritonavir has been shown to acutely block glucose transport in vitro and in vivo. Taken together, our studies not only demonstrate an essential role of cellular glucose metabolism on WST-8 reduction, but also propose a novel application of tetrazolium-based assays in screening for inhibitors of cellular glucose metabolism when used in combination with ATP assay.

Effect of Food on the Pharmacokinetics of Saroglitazar Magnesium, a Novel Dual PPARαγ Agonist, in Healthy Adult Subjects

Peroxisome proliferator-activated receptors (PPARs) have recently become a focus of interest for their important roles in glucose and lipid metabolism. In humans, PPARα activation causes a decrease in plasma triglyceride (TG) levels, enhancement of high-density lipoprotein cholesterol (HDL-C) and simultaneous enhancement of very-low-density lipoprotein (VLDL) lipolysis, whereas PPARγ agonists act as insulin sensitizers and improve insulin resistance, which is very useful in patients with type 2 diabetes mellitus (T2DM). Saroglitazar magnesium is a dual PPAR agonist with potent predominant PPARα and moderate PPARγ activity and the first glitazar to be granted marketing authorization in India. This study was conducted to evaluate the oral bioavailability and safety and tolerability of a Lipaglyn™ (saroglitazar magnesium) 4-mg tablet in healthy, adult human subjects under fed relative to fasting conditions. This was a single-dose, open-label, randomized, single-treatment, two-period, two-conditions (fed vs. fasting), two-sequence, crossover study planned in 54 healthy subjects. Food effect (high-calorie and high-fat breakfast) was examined by comparing pharmacokinetic data of saroglitazar and its metabolite saroglitazar sulfoxide in plasma samples collected pre-dose and serially up to 72h post-dose. Pharmacokinetic data were analyzed using the standard non-compartmental approach. A total of 54 subjects were enrolled in the study, out of them 50 subjects had completed the study and were analyzed. The presence of food had a minor impact on the disposition of saroglitazar. While food reduced C max (maximum concentration) of saroglitazar by 30%, the extent of absorption as measured by AUC∞ (area under the concentration time curve from time zero to infinity) was not influenced. This was further supported by the bioequivalence data between fasted and fed conditions for saroglitazar, where 90% CIs (confidence intervals) of the adjusted geometric mean of the fed relative to the fasted condition ranged from 101.37% to 108.07% for AUC∞ and from 63.45% to 74.68% for C max. Other parameters such as T max (time of maximum concentration) and T 1/2 (elimination half-life) were not influenced by the food intake. Saroglitazar was well tolerated in the study, and the reported adverse events were mild in nature. For the single-dose study, the absorption rate is affected by food as the 90% CI of C max is outside 80.00-125.00%. However, there is no impact of food on the extent of absorption of saroglitazar. The observed lower C max of saroglitazar with food has no clinical relevance since the therapeutic efficacy of saroglitazar was achieved after multiple-dose administration, suggesting the importance of total exposure.

Molecular cloning and characterization of glycogen synthase in Eriocheir sinensis.

Glycogen plays an important role in glucose and energy homeostasis at cellular and organismal levels. In glycogen synthesis, glycogen synthase (GS) is a rate-limiting enzyme catalysing the addition of α-1,4-linked glucose units from (UDP)3-glucose to a nascent glycogen chain using glycogenin (GN) as a primer. While studies on mammalian liver GS (GYS2) are numerous, enzymes from crustaceans, which also use glycogen and glucose as their main energy source, have received less attention. In the present study, we amplified full-length GS cDNA from Eriocheir sinensis. Tissue expression profiling revealed the highest expression of GS in the hepatopancreas. During moulting, GS expression and activity declined, and glycogen levels in the hepatopancreas were reduced. Recombinant GS was expressed in Escherichia coli Rosetta (DE3), and induction at 37°C or 16°C yielded EsGS in insoluble inclusion bodies (EsGS-I) or in soluble form (EsGS-S), respectively. Enzyme activity was measured in a cell-free system containing glucose-6-phosphate (G6P), and both forms possessed glycosyltransferase activity, but refolded EsGS-I was more active. Enzyme activity of both GS and EsGS-I in the hepatopancreas was optimum at 25°C, which is coincident with the optimum growth temperature of Chinese mitten crab, and higher (37°C) or lower (16°C) temperatures resulted in lower enzyme activity. Taken together, the results suggest that GS may be important for maintaining normal physiological functions such as growth and reproduction.

SUN-P071: The Role of Glucose, Insulin, and Glucagon During Liver Regeneration After Partial Hepatectomy

SUN-P071: The Role of Glucose, Insulin, and Glucagon During Liver Regeneration After Partial Hepatectomy

The role of glucose, insulin and NEFA in regulating tissue triglyceride accumulation: Substrate cooperation in adipose tissue versus substrate competition in skeletal muscle

Background and aimsMetabolic factors initiating adipose tissue expansion and ectopic triglyceride accumulation are not completely understood. We aimed to investigate the independent role of circulating glucose, NEFA and insulin on glucose and NEFA uptake, and lipogenesis in skeletal muscle and subcutaneous adipose tissue (SCAT). Methods and resultsTwenty-two pigs were stratified according to four protocols: 1) and 2) low NEFA + high insulin ± high glucose (hyperinsulinaemia–hyperglycaemia or hyperinsulinaemia–euglycaemia), 3) high NEFA + low insulin (fasting), 4) low NEFA + low insulin (nicotinic acid). Positron emission tomography with [18F]fluoro-2-deoxyglucose and [11C]acetate, was combined with [14C]acetate and [U-13C]palmitate enrichment techniques to assess glucose and lipid metabolism.Hyperinsulinaemia increased glucose extraction, whilst hyperglycaemia enhanced glucose uptake in skeletal muscle and SCAT. In SCAT, during hyperglycaemia, elevated glucose uptake was accompanied by greater [U-13C]palmitate-TG enrichment compared to the other groups, and by a 39% increase in de novo lipogenesis (DNL) compared to baseline, consistent with a 70% increment in plasma lipogenic index. Conversely, in skeletal muscle, [U-13C]palmitate-TG enrichment was higher after prolonged fasting. ConclusionsOur data show the necessary role of hyperglycaemia–hyperinsulinaemia vs euglycaemia–hyperinsulinaemia in promoting expansion of TG stores in SCAT, by the consensual elevation in plasma NEFA and glucose uptake and DNL. In contrast, skeletal muscle NEFA uptake for TG synthesis is primarily driven by circulating NEFA levels. These results suggest that a) prolonged fasting or dietary regimens enhancing lipolysis might promote muscle steatosis, and b) the control of glucose levels, in association with adequate energy balance, might contribute to weight loss.

Increased glycine-amidated hyocholic acid correlates to improved early weight loss after sleeve gastrectomy.

Bile acids (BAs) are post-prandial hormones that play an important role in glucose and lipid homeostasis as well as energy expenditure. Total and glycine-amidated BAs increase after sleeve gastrectomy (SG) and correlate to improved metabolic disease. No specific bile acid subtype has been shown conclusively to mediate the weight loss effect. Therefore, the objective of this study was to prospectively evaluate the comprehensive changes in meal-stimulated BAs after SG and determine if a specific change in the BA profile correlates to the early weight loss response. Patients were prospectively enrolled at the University of Nebraska Medical Center who were undergoing a SG for treatment of morbid obesity. Primary and secondary plasma bile acids and their amidated (glycine, G-, or taurine, T-) subtypes were measured at fasting, 30 and 60min after a liquid meal performed pre-op, and at 6 and 12weeks post-op. Area under the curve (AUC) was calculated for the hour meal test for each bile acid subtype. BAs that were significantly increased post-op were correlated to body mass index (BMI) loss. Total BA AUC was significantly increased at 6 (p<0.01) and 12weeks post-op (p<0.01) compared to pre-operative values. The increase in total BA AUC was due to a statistically significant increase in G-BAs. Nine different BA AUC subtypes were significantly increased at both 6 and 12weeks post-op. Increased total and G-chenodeoxycholic acid AUC was significantly correlated to the 6week BMI loss (p=0.03). Increased G-hyocholic acid was significantly correlated to increased weight loss at both 6 (p=0.05) and 12weeks (p=0.006). SG induced an early and persistent post-prandial surge in multiple bile acid subtypes. Increased G-hyocholic consistently correlated with greater early BMI loss. This study provides evidence for a role of BAs in the surgical weight loss response after SG.

GPR120 suppresses adipose tissue lipolysis and synergizes with GPR40 in antidiabetic efficacy

GPR40 and GPR120 are fatty acid sensors that play important roles in glucose and energy homeostasis. GPR40 potentiates glucose-dependent insulin secretion and demonstrated in clinical studies robust glucose lowering in type 2 diabetes. GPR120 improves insulin sensitivity in rodents, albeit its mechanism of action is not fully understood. Here, we postulated that the antidiabetic efficacy of GPR40 could be enhanced by coactivating GPR120. A combination of GPR40 and GPR120 agonists in db/db mice, as well as a single molecule with dual agonist activities, achieved superior glycemic control compared with either monotherapy. Compared with a GPR40 selective agonist, the dual agonist improved insulin sensitivity in ob/ob mice measured by hyperinsulinemic-euglycemic clamp, preserved islet morphology, and increased expression of several key lipolytic genes in adipose tissue of Zucker diabetic fatty rats. Novel insights into the mechanism of action for GPR120 were obtained. Selective GPR120 activation suppressed lipolysis in primary white adipocytes, although this effect was attenuated in adipocytes from obese rats and obese rhesus, and sensitized the antilipolytic effect of insulin in rat and rhesus primary adipocytes. In conclusion, GPR120 agonism enhances insulin action in adipose tissue and yields a synergistic efficacy when combined with GPR40 agonism.

Fibroblast Growth Factor 21-Metabolic Role in Mice and Men.

Since its identification in 2000, the interest of scientists in the hepatokine fibroblast growth factor (FGF) 21 has tremendously grown, and still remains high, due to a wealth of very robust data documenting this factor's favorable effects on glucose and lipid metabolism in mice. For more than ten years now, intense in vivo and ex vivo experimentation addressed the physiological functions of FGF21 in humans as well as its pathophysiological role and pharmacological effects in human metabolic disease. This work produced a comprehensive collection of data revealing overlaps in FGF21 expression and function but also significant differences between mice and humans that have to be considered before translation from bench to bedside can be successful. This review summarizes what is known about FGF21 in mice and humans with a special focus on this factor's role in glucose and lipid metabolism and in metabolic diseases, such as obesity and type 2 diabetes mellitus. We highlight the discrepancies between mice and humans and try to decipher their underlying reasons.

D-mannose induces regulatory T cells and suppresses immunopathology.

D-mannose, a C-2 epimer of glucose, exists naturally in many plants and fruits, and is found in human blood at concentrations less than one-fiftieth of that of glucose. However, although the roles of glucose in T cell metabolism, diabetes and obesity are well characterized, the function of D-mannose in T cell immune responses remains unknown. Here we show that supraphysiological levels of D-mannose safely achievable by drinking-water supplementation suppressed immunopathology in mouse models of autoimmune diabetes and airway inflammation, and increased the proportion of Foxp3+ regulatory T cells (Treg cells) in mice. In vitro, D-mannose stimulated Treg cell differentiation in human and mouse cells by promoting TGF-β activation, which in turn was mediated by upregulation of integrin αvβ8 and reactive oxygen species generated by increased fatty acid oxidation. This previously unrecognized immunoregulatory function of D-mannose may have clinical applications for immunopathology.

The Influence of Polyploidy on the Evolution of Yeast Grown in a Sub-Optimal Carbon Source.

Polyploidization events have occurred during the evolution of many fungi, plant, and animal species and are thought to contribute to speciation and tumorigenesis, however little is known about how ploidy level contributes to adaptation at the molecular level. Here we integrate whole genome sequencing, RNA expression analysis, and relative fitness of ∼100 evolved clones at three ploidy levels. Independent haploid, diploid, and tetraploid populations were grown in a low carbon environment for 250 generations. We demonstrate that the key adaptive mutation in the evolved clones is predicted by a gene expression signature of just five genes. All of the adaptive mutations identified encompass a narrow set of genes, however the tetraploid clones gain a broader spectrum of adaptive mutations than haploid or diploid clones. While many of the adaptive mutations occur in genes that encode proteins with known roles in glucose sensing and transport, we discover mutations in genes with no canonical role in carbon utilization (IPT1 and MOT3), as well as identify novel dominant mutations in glucose signal transducers thought to only accumulate recessive mutations in carbon limited environments (MTH1 and RGT1). We conclude that polyploid cells explore more genotypic and phenotypic space than lower ploidy cells. Our study provides strong evidence for the beneficial role of polyploidization events that occur during the evolution of many species and during tumorigenesis.

Abstract 15: Glucose-Mediated Remodeling of Cardiac DNA Methylation

To identify the role of glucose in the development of diabetic cardiomyopathy, we had directly assessed glucose delivery to the intact heart on alterations of DNA methylation and gene expression using both an inducible heart-specific transgene (glucose transporter 4; mG4H) and streptozotocin-induced diabetes (STZ) mouse models. We aimed to determine whether long-lasting diabetic complications arise from prior transient exposure to hyperglycemia via a process termed “glycemic memory.” We had identified DNA methylation changes associated with significant gene expression regulation. Comparing our results from STZ, mG4H, and the modifications which persist following transgene silencing, we now provide evidence for cardiac DNA methylation as a persistent epigenetic mark contributing to glycemic memory. To begin to determine which changes contribute to human heart failure, we measured both RNA transcript levels and whole-genome DNA methylation in heart failure biopsy samples (n = 12) from male patients collected at left ventricular assist device placement using RNA-sequencing and Methylation450 assay, respectively. We hypothesized that epigenetic changes such as DNA methylation distinguish between heart failure etiologies. Our findings demonstrated that type 2 diabetic heart failure patients (n = 6) had an overall signature of hypomethylation, whereas patients listed as ischemic (n = 5) had a distinct hypermethylation signature for regulated transcripts. The focus of this initial analysis was on promoter-associated CpG islands with inverse changes in gene transcript levels, from which diabetes (14 genes; e.g. IGFBP4) and ischemic (12 genes; e.g. PFKFB3) specific targets emerged with significant regulation of both measures. By combining our mouse and human molecular analyses, we provide evidence that diabetes mellitus governs direct regulation of cellular function by DNA methylation and the corresponding gene expression in diabetic mouse and human hearts. Importantly, many of the changes seen in either mouse type 1 diabetes or human type 2 diabetes were similar supporting a consistent mechanism of regulation. These studies are some of the first steps at defining mechanisms of epigenetic regulation in diabetic cardiomyopathy.

Single-cell study links metabolism with nutrient signaling and reveals sources of variability

BackgroundThe yeast AMPK/SNF1 pathway is best known for its role in glucose de/repression. When glucose becomes limited, the Snf1 kinase is activated and phosphorylates the transcriptional repressor Mig1, which is then exported from the nucleus. The exact mechanism how the Snf1-Mig1 pathway is regulated is not entirely elucidated.ResultsGlucose uptake through the low affinity transporter Hxt1 results in nuclear accumulation of Mig1 in response to all glucose concentrations upshift, however with increasing glucose concentration the nuclear localization of Mig1 is more intense. Strains expressing Hxt7 display a constant response to all glucose concentration upshifts. We show that differences in amount of hexose transporter molecules in the cell could cause cell-to-cell variability in the Mig1-Snf1 system. We further apply mathematical modelling to our data, both general deterministic and a nonlinear mixed effect model. Our model suggests a presently unrecognized regulatory step of the Snf1-Mig1 pathway at the level of Mig1 dephosphorylation. Model predictions point to parameters involved in the transport of Mig1 in and out of the nucleus as a majorsource of cell to cell variability.ConclusionsWith this modelling approach we have been able to suggest steps that contribute to the cell-to-cell variability. Our data indicate a close link between the glucose uptake rate, which determines the glycolytic rate, and the activity of the Snf1/Mig1 system. This study hence establishes a close relation between metabolism and signalling.

Identification of Differentially Expressed Micrornas Associate with Glucose Metabolism in Different Organs of Blunt Snout Bream (Megalobrama amblycephala).

Blunt snout bream (Megalobrama amblycephala) is a widely favored herbivorous fish species and is a frequentlyused fish model for studying the metabolism physiology. This study aimed to provide a comprehensive illustration of the mechanisms of a high-starch diet (HSD) induced lipid metabolic disorder by identifying microRNAs (miRNAs) controlled pathways in glucose and lipid metabolism in fish using high-throughput sequencing technologies. Small RNA libraries derived from intestines, livers, and brains of HSD and normal-starch diet (NSD) treated M. amblycephala were sequenced and 79, 124 and 77 differentially expressed miRNAs (DEMs) in intestines, livers, and brains of HSD treated fish were identified, respectively. Bioinformatics analyses showed that these DEMs targeted hundreds of predicted genes were enriched into metabolic pathways and biosynthetic processes, including peroxisome proliferator-activated receptor (PPAR), glycolysis/gluconeogenesis, and insulin signaling pathway. These analyses confirmed that miRNAs play crucial roles in glucose and lipid metabolism related to high wheat starch treatment. These results provide information on further investigation of a DEM-related mechanism dysregulated by a high carbohydrate diet.

Even- and odd-chain saturated fatty acids in serum phospholipids are differentially associated with adipokines.

BackgroundSaturated fatty acids are generally thought to have detrimental effects on health. However, a recent study showed that even- and odd-chain saturated fatty acids had opposite associations with type 2 diabetes. Limited studies of Western populations examined the associations of circulating saturated fatty acids with adipokines, an important role in glucose metabolism.ObjectiveWe examined the associations of saturated fatty acids in serum phospholipids with circulating levels of adipokines among a Japanese population.DesignA cross-sectional study was conducted among 484 Japanese employees (284 men and 200 women) aged 20–65 years. The serum fatty acid composition in the phospholipid fraction was measured by gas-chromatography. Serum leptin, adiponectin, plasminogen activator inhibitor-1 (PAI-1), resistin, and visfatin were measured using a Luminex suspension bead-based multiplexed array. Multiple linear regression analysis was performed to assess the association between saturated fatty acids and adipokines, with adjustment for potential confounding variables.ResultsEven- and odd-chain saturated fatty acids were differentially associated with adipokines. Higher levels of even-chain saturated fatty acids (14:0 myristic, 16:0 palmitic, and 18:0 stearic acids) were associated with higher levels of resistin (P for trend = 0.048) and lower levels of adiponectin (P for trend = 0.003). By contrast, odd-chain saturated fatty acids (15:0 pentadecanoic and 17:0 heptadecanoic acids) showed inverse associations with leptin and PAI-1 (P for trend = 0.048 and 0.02, respectively). Visfatin was positively associated with both even- and odd-chain saturated fatty acids.ConclusionsThe results suggest that even- and odd-chain saturated fatty acids are differentially associated with adipokine profile.

Regulation role of CRTC3 in skeletal muscle and adipose tissue

The cyclic adenosine monophosphate (cAMP)-protein kinase A (PKA) signaling pathway plays important role in regulating energy homeostasis. Many of the effects of the cAMP-PKA signaling is mediated through the cAMP responsive element binding protein (CREB) and its coactivator CREB-regulated transcription coactivators (CRTCs). CRTC3 is a member of CRTCs family proteins and plays important roles in glucose and energy metabolism. Previous studies show that global knockout of CRTC3 enhances oxygen consumption and energy expenditure and subsequently protects the knockout animal against obesity. In skeletal muscle, CRTC3 affects lipid and glycogen metabolism and mitochondrial biogenesis. In white adipocytes, CRTC3 regulates GLUT4 expression and glucose uptake. More recently, the localization and function of CRTC3 in brown fat have been reported. In this review, we mainly discuss the regulatory role of CRTC3 in skeletal muscle and adipose tissues.