AMP activated kinase negatively regulates hepatic Fetuin-A via p38 MAPK-C/EBPβ/E3 Ubiquitin Ligase Signaling pathway.

Fetuin-A (Fet-A) is a liver-secreted phosphorylated protein, known to impair insulin signaling, which has been shown to be associated with obesity, insulin resistance, and incident diabetes. Fet-A interacts with the insulin-stimulated insulin receptor (IR) and inhibits IR tyrosine kinase activity and glucose uptake. It has been shown that high glucose increases Fet-A expression through the ERK1/2 signaling pathway.

Serum fetuin-A and Ser312 phosphorylated fetuin-A responses and markers of insulin sensitivity after a single bout of moderate intensity exercise.

Fetuin-A (Fet-A), secreted by the liver and adipose tissue, inhibits insulin receptor tyrosine kinase activity and modulates insulin action. Numerous studies have shown association of elevated serum Fet-A concentrations with obesity, non-alcoholic fatty liver disease, and type 2 diabetes. Both moderate body weight loss (5%-10%) and significant body weight loss have been shown to decrease serum Fet-A and improve insulin sensitivity.

Alterations of Serum Ser312-Phosphorylated Fetuin-A from Exercise-Induced Moderate Body Weight Loss in Individuals with Obesity.

Objective: Phosphorylated fetuin-A (pFet-A) inhibits insulin action and has been shown to be associated with obesity and insulin resistance. The objective of this cohort study was to assess the effect of incremental body weight loss on alterations in serum pFet-A and indexes of insulin sensitivity.

Methods: A total of 16 men with obesity attained a targeted weight loss of 8% to 10% of their initial body weight by achieving an energy expenditure/deficit of 2,000 to 2,500 kcal/wk.

Phosphorylation status of fetuin-A is critical for inhibition of insulin action and is correlated with obesity and insulin resistance.

Fetuin-A (Fet-A), a hepatokine associated with insulin resistance, obesity, and incident type 2 diabetes, is shown to exist in both phosphorylated and dephosphorylated forms in circulation. However, studies on fetuin-A phosphorylation status in insulin-resistant conditions and its functional significance are limited. We demonstrate that serum phosphofetuin-A (Ser312) levels were significantly elevated in high-fat diet-induced obese mice, insulin-resistant Zucker diabetic fatty rats, and in individuals with obesity who are insulin resistant.

AMPK activation by pterostilbene contributes to suppression of hepatic gluconeogenic gene expression and glucose production in H4IIE cells.

Pterostilbene, a bioactive component of blueberries and grapes, shows structural similarity to resveratrol, and exhibits antioxidant, anti-inflammatory, anti-cancer, hypoglycemic, and cholesterol lowering effects. Recent evidence indicates that pterostilbene is an agonist of the nuclear receptor, peroxisome proliferator-activated receptor-alpha (PPAR-α). Since PPAR-α agonists induce peroxisomal proliferation and fatty acid oxidation, we examined gene expression of acyl CoA oxidase (ACO) and carnitine palmitoyl transferase-1 (CPT-1).

α-Glucosidase inhibitory effect of resveratrol and piceatannol.

Dietary polyphenols have been shown to inhibit α-glucosidase, an enzyme target of some antidiabetic drugs. Resveratrol, a polyphenol found in grapes and wine, has been reported to inhibit the activity of yeast α-glucosidase. This triggered our interest to synthesize analogs and determine their effect on mammalian α-glucosidase activity.

Hypoglycemic agents and potential anti-inflammatory activity.

Current literature shows an association of diabetes and secondary complications with chronic inflammation. Evidence of these immunological changes include altered levels of cytokines and chemokines, changes in the numbers and activation states of various leukocyte populations, apoptosis, and fibrosis during diabetes. Therefore, treatment of diabetes and its complications may include pharmacological strategies to reduce inflammation.

Comparison of Chemiluminescence vs. Infrared Techniques for Detection of Fetuin-A in Saliva.

The western blotting technique for transfer and detection of proteins, named following the discovery of southern and northern blotting for DNA- and RNA-blotting, respectively, has traditionally relied on the use of X-ray films to capture chemiluminescence. Recent advancements use super-cooled charge coupled devices (CCD) cameras to capture both chemiluminescence and fluorescence images, which exhibit a greater dynamic range compared to traditional X-ray film. Chemiluminescence detected by a CCD camera records photons and displays an image based on the amount of light generated as a result of a dynamic chemical reaction.

Detection of Blotted Proteins: Not All Blockers Are Created Equal.

Western blotting is a standard analytical technique for detection of proteins. It is dependent on a number of components; from the specificity of the primary antibody to the reduction of competing biomolecules present in the assay. Blocking agents are a critical component for western blotting protocols as these diminish nonspecific binding by blocking off-target sites on the membrane.

Blood Glucose-lowering Effect of T. procumbens L.: A Pilot Clinical Study in Individuals with Type 2 Diabetes.

Traditional knowledge, in vitro studies, and studies using animal models suggest that Tridax procumbens L. exhibits blood glucose-lowering properties and antiinflammatory effects. In this study, we evaluated the blood glucose-lowering effect of T.

Evaluation of PPARα activation by known blueberry constituents.

Background: Anthocyanins are known to have hypolipidemic properties. It was deemed necessary to determine whether major blueberry anthocyanins and catechins are ligands for the transcription factor peroxisome proliferator activated receptor alpha isoform (PPARα), and compare activation with known PPARα agonistic constituents, pterostilbene and resveratrol. It was also considered important to investigate the effect of pterostilbene on PPARα gene expression, and relate results with hepatic mRNA PPARα expression up-regulation observed previously in hamsters fed a diet supplemented with blueberry peels extract (BBX).

Saliva as a non-invasive diagnostic tool for inflammation and insulin-resistance.

Saliva has been progressively studied as a non-invasive and relatively stress-free diagnostic alternative to blood. Currently, saliva testing is used for clinical assessment of hormonal perturbations, detection of HIV antibodies, DNA analysis, alcohol screening, and drug testing. Recently, there has been increasing interest in evaluating the diagnostic potential of saliva in obesity, inflammation, and insulin-resistance.

The pancreas-brain axis: insight into disrupted mechanisms associating type 2 diabetes and Alzheimer's disease.

Epidemiological and observational studies indicate a positive correlation between type 2 diabetes (T2DM) and dementia, with an increased risk of dementia and Alzheimer's disease (AD) associated with insulin-treated diabetes patients. The purpose of this review is to reveal the molecular mechanisms that connect physiological and pathological processes commonly observed in T2DM and AD. Conformational modifications in peptide residues, such as amyloid-β peptide in AD and amylin in T2DM have been shown to instigate formation of insoluble protein aggregates that get deposited in extracellular spaces of brain and pancreatic tissue thus disrupting their normal function.

Resveratrol protects the brain of obese mice from oxidative damage.

Resveratrol (3,5,4'-trihydroxy-trans-stilbene) is a polyphenolic phytoalexin that exerts cardioprotective, neuroprotective, and antioxidant effects. Recently it has been shown that obesity is associated with an increase in cerebral oxidative stress levels, which may enhance neurodegeneration. The present study evaluates the neuroprotective action of resveratrol in brain of obese (ob/ob) mice.

Serviceberry [Amelanchier alnifolia (Nutt.) Nutt. ex. M. Roem (Rosaceae)] leaf extract inhibits mammalian α-glucosidase activity and suppresses postprandial glycemic response in a mouse model of diet-induced obesity and hyperglycemia.

Ethnopharmacological Relevance: Serviceberry or Saskatoon berry [Amelanchier alnifolia (Nutt.) Nutt. ex.

Ultrasensitive protein detection and imaging: comparison of Lumitein™, ProteoSilver™, SYPRO(®) Ruby, and Coomassie (®) Brilliant Blue gel stains.

Following sodium dodecyl sulfate polyacrylamide gel electrophoresis, proteins can be visualized by various methods of detection and imaging. Traditional methods of protein gel detection and imaging have been improved and expanded through technological advancement. Today, the detection of proteins, resolved on gels, can be accomplished with a variety of stains with various sensitivities.

Endogenously produced adiponectin protects cardiomyocytes from hypertrophy by a PPARgamma-dependent autocrine mechanism.

In experimental animal and cell culture models, activation of peroxisome proliferator-activated receptor (PPAR) gamma in heart has been shown to have beneficial effects on cardiac function and cardiomyocyte physiology. The goal of this study was to identify the signaling pathway by which PPARgamma activation protects cardiomyocytes from the deleterious effects of hypertrophic stimuli. In primary cardiomyocyte cultures, we found that genetic or pharmacological activation of PPARgamma protected cells from cardiac hypertrophy induced by alpha-adrenergic stimulation.

Selective activation of PPARgamma in skeletal muscle induces endogenous production of adiponectin and protects mice from diet-induced insulin resistance.

The nuclear receptor peroxisome proliferator-activated receptor (PPAR)gamma plays a key role in regulating whole body glucose homeostasis and insulin sensitivity. Although it is expressed most highly in adipose, it is also present at lower levels in many tissues, including skeletal muscle. The role muscle PPARgamma plays in metabolic regulation and in mediating the antidiabetic effects of the thiazolidinediones is not understood.

Curcumin activates AMPK and suppresses gluconeogenic gene expression in hepatoma cells.

Curcumin, the bioactive component of curry spice turmeric, and its related structures possess potent anti-oxidant and anti-inflammatory properties. Several lines of evidence suggest that curcumin may play a beneficial role in animal models of diabetes, both by lowering blood glucose levels and by ameliorating the long-term complications of diabetes. However, current understanding of the mechanism of curcumin action is rudimentary and is limited to its anti-oxidant and anti-inflammatory effects.

Extended-release niacin decreases serum fetuin-A concentrations in individuals with metabolic syndrome.

Background: Fetuin-A, a liver-secreted phosphoprotein and physiological inhibitor of insulin receptor tyrosine kinase, is associated with insulin resistance, metabolic syndrome (MetS), and an increased risk for type 2 diabetes. However, studies on the modulation of circulating levels of fetuin-A are limited. The goal of this study was to determine the effect of niacin administration on serum total- and phosphorylated fetuin-A (phosphofetuin-A) concentrations in individuals with MetS and correlate with changes in serum lipids, insulin sensitivity, and markers of inflammation.

Imaging systems for westerns: chemiluminescence vs. infrared detection.

Western blot detection methods have traditionally used X-ray films to capture chemiluminescence. The increasing costs for film, reagents, and maintenance have driven researchers away from darkrooms to more sensitive and technologically advanced digital imaging systems. Cooled charge coupled devices (CCD) cameras capture both chemiluminescence and fluorescence images, with limitations for each detection method.

Fetuin-null mice are protected against obesity and insulin resistance associated with aging.

alpha2-HS glycoprotein (AHSG), also known as fetuin-A, inhibits insulin receptor autophosphorylation and tyrosine kinase activity in vitro and in vivo. Earlier we have shown that fetuin-null (KO) mice demonstrate improved insulin sensitivity and resistance to diet-induced obesity. Since aging is associated with insulin resistance and impaired glucose handling, we tested the hypothesis that fetuin-null (KO) mice are resilient to changes in insulin sensitivity associated with aging.

Review: peroxisome proliferator-activated receptor-gamma and its role in the development and treatment of diabetes.

Since its identification as the receptor for antidiabetic thiazolidinedione drugs, peroxisome proliferator-activated receptor-gamma (PPARgamma) has been the focus of pharmaceutical drug discovery programs directed toward finding better drugs for the treatment of diabetes, as well as the object of basic research aimed at understanding its role in the regulation of metabolism. We now understand a great deal about the crucial role that PPARgamma plays in adipocyte differentiation and development, and are rapidly gaining knowledge about the role of the receptor in the regulation of metabolism. However, many crucial aspects of the molecular mechanism by which modulation of PPARgamma activity affects insulin resistance and glucose homeostasis are still not clearly understood.

Poly-L-histidine downregulates fibrinolysis.

The elevated level of histidine-rich glycoprotein was considered a risk factor of inherited thrombophilia. However, the mode of action remains largely unclear. In the current study, we employ poly-l-histidine (PLH) mimicking the histidine-rich region and determine whether PLH modulates urokinase (uPA)-dependent fibrinolysis.

Novel anticoagulant activity of polyamino acid offsets bacterial endotoxin-induced extrinsic hypercoagulation: downregulation of monocytic tissue factor-dependent FVII activation.

The extrinsic hypercoagulation often resulting from sepsis could contribute to disseminated intravascular coagulation and cardiovascular complications. The effective prevention and intervention remained largely complex and unclear. In a cell model of human leukemia THP-1 monocytes following bacterial endotoxin (LPS) exposure, we show the novel anticoagulant ability of polyamino acid (polyAA) to suppress the extrinsic hypercoagulation.