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1.
Nat Rev Mol Cell Biol ; 16(6): 345-59, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25970558

ABSTRACT

Recent advances in mitochondrial biology have revealed the high diversity and complexity of proteolytic enzymes that regulate mitochondrial function. We have classified mitochondrial proteases, or mitoproteases, on the basis of their function and location, and defined the human mitochondrial degradome as the complete set of mitoproteases that are encoded by the human genome. In addition to their nonspecific degradative functions, mitoproteases perform highly regulated proteolytic reactions that are important in mitochondrial function, integrity and homeostasis. These include protein synthesis, quality control, mitochondrial biogenesis and dynamics, mitophagy and apoptosis. Impaired or dysregulated function of mitoproteases is associated with ageing and with many pathological conditions such as neurodegenerative disorders, metabolic syndromes and cancer. A better understanding of the mitochondrial proteolytic landscape and its modulation may contribute to improving human lifespan and 'healthspan'.


Subject(s)
Aging/metabolism , Metabolic Syndrome/enzymology , Mitochondria/enzymology , Mitochondrial Proteins/metabolism , Neoplasm Proteins/metabolism , Neoplasms/enzymology , Neurodegenerative Diseases/enzymology , Peptide Hydrolases/metabolism , Aging/genetics , Aging/pathology , Animals , Genome, Human , Humans , Metabolic Syndrome/genetics , Metabolic Syndrome/pathology , Mitochondria/genetics , Mitochondria/pathology , Mitochondrial Proteins/genetics , Neoplasm Proteins/genetics , Neoplasms/genetics , Neoplasms/pathology , Neurodegenerative Diseases/genetics , Neurodegenerative Diseases/pathology , Peptide Hydrolases/genetics , Proteolysis
2.
Mol Cell Biochem ; 477(4): 1309-1320, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35138512

ABSTRACT

The prevalence of the metabolic syndrome (MetS) and its cardiac comorbidities as cardiac hypertrophy (CH) have increased considerably due to the high consumption of carbohydrates, such as sucrose and/or fructose. We compared the effects of sucrose (S), fructose (F) and their combination (S + F) on the development of MetS in weaned male Wistar rats and established the relationship between the consumption of these sugars and the degree of cardiac CH development, oxidative stress (OS) and Calcium/calmodulin-dependent protein kinase type II subunit delta oxidation (ox-CaMKIIδ). 12 weeks after the beginning of treatments with S, F or S + F, arterial pressure was measured and 8 weeks later (to complete 20 weeks) the animals were sacrificed and blood samples, visceral adipose tissue and hearts were obtained. Biochemical parameters were determined in serum and cardiac tissue to evaluate the development of MetS and OS. To evaluate CH, atrial natriuretic peptide (ANP), CaMKIIδ and ox-CaMKIIδ were determined by western blot and histological studies were performed in cardiac tissue. Our data showed that chronic consumption of S + F exacerbates MetS-induced CH which is related with a higher OS and ox-CaMKIIδ.


Subject(s)
Calcium-Calmodulin-Dependent Protein Kinase Type 2/metabolism , Cardiomegaly/enzymology , Dietary Carbohydrates/adverse effects , Fructose/adverse effects , Metabolic Syndrome/enzymology , Myocardium/enzymology , Oxidative Stress/drug effects , Sucrose/adverse effects , Animals , Dietary Carbohydrates/pharmacology , Fructose/pharmacology , Male , Oxidation-Reduction/drug effects , Rats , Rats, Wistar , Sucrose/pharmacology
3.
Am J Physiol Heart Circ Physiol ; 320(3): H999-H1016, 2021 03 01.
Article in English | MEDLINE | ID: mdl-33416454

ABSTRACT

We aimed to determine 1) the mechanism(s) that enables glucose-6-phosphate dehydrogenase (G6PD) to regulate serum response factor (SRF)- and myocardin (MYOCD)-driven smooth muscle cell (SMC)-restricted gene expression, a process that aids in the differentiation of SMCs, and 2) whether G6PD-mediated metabolic reprogramming contributes to the pathogenesis of vascular diseases in metabolic syndrome (MetS). Inhibition of G6PD activity increased (>30%) expression of SMC-restricted genes and concurrently decreased (40%) the growth of human and rat SMCs ex vivo. Expression of SMC-restricted genes decreased (>100-fold) across successive passages in primary cultures of SMCs isolated from mouse aorta. G6PD inhibition increased Myh11 (47%) while decreasing (>50%) Sca-1, a stem cell marker, in cells passaged seven times. Similarly, CRISPR-Cas9-mediated expression of the loss-of-function Mediterranean variant of G6PD (S188F; G6PDS188F) in rats promoted transcription of SMC-restricted genes. G6PD knockdown or inhibition decreased (48.5%) histone deacetylase (HDAC) activity, enriched (by 3-fold) H3K27ac on the Myocd promoter, and increased Myocd and Myh11 expression. Interestingly, G6PD activity was significantly higher in aortas from JCR rats with MetS than control Sprague-Dawley (SD) rats. Treating JCR rats with epiandrosterone (30 mg/kg/day), a G6PD inhibitor, increased expression of SMC-restricted genes, suppressed Serpine1 and Epha4, and reduced blood pressure. Moreover, feeding SD control (littermates) and G6PDS188F rats a high-fat diet for 4 mo increased Serpine1 and Epha4 expression and mean arterial pressure in SD but not G6PDS188F rats. Our findings demonstrate that G6PD downregulates transcription of SMC-restricted genes through HDAC-dependent deacetylation and potentially augments the severity of vascular diseases associated with MetS.NEW & NOTEWORTHY This study gives detailed mechanistic insight about the regulation of smooth muscle cell (SMC) phenotype by metabolic reprogramming and glucose-6-phosphate dehydrogenase (G6PD) in diabetes and metabolic syndrome. We demonstrate that G6PD controls the chromatin modifications by regulating histone deacetylase (HDAC) activity, which deacetylates histone 3-lysine 9 and 27. Notably, inhibition of G6PD decreases HDAC activity and enriches H3K27ac on myocardin gene promoter to enhance the expression of SMC-restricted genes. Also, we demonstrate for the first time that G6PD inhibitor treatment accentuates metabolic and transcriptomic reprogramming to reduce neointimal formation in coronary artery and large artery elastance in metabolic syndrome rats.


Subject(s)
Glucosephosphate Dehydrogenase/metabolism , Histones/metabolism , Metabolic Syndrome/enzymology , Muscle, Smooth, Vascular/enzymology , Myocytes, Smooth Muscle/enzymology , Protein Processing, Post-Translational , Acetylation , Animals , Cell Line , Disease Models, Animal , Female , Gene Expression Regulation , Glucosephosphate Dehydrogenase/genetics , Hemodynamics , Humans , Male , Metabolic Syndrome/genetics , Metabolic Syndrome/pathology , Metabolic Syndrome/physiopathology , Mice, Transgenic , Muscle, Smooth, Vascular/pathology , Muscle, Smooth, Vascular/physiopathology , Mutation , Myocytes, Smooth Muscle/pathology , Myosin Heavy Chains/genetics , Myosin Heavy Chains/metabolism , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Rats, Sprague-Dawley , Serum Response Factor/genetics , Serum Response Factor/metabolism , Trans-Activators/genetics , Trans-Activators/metabolism , Transcription Factors/genetics , Transcription Factors/metabolism , Vascular Remodeling
4.
5.
Cardiovasc Drugs Ther ; 34(4): 487-501, 2020 08.
Article in English | MEDLINE | ID: mdl-32377826

ABSTRACT

BACKGROUND: Previous studies have demonstrated that a high-carbohydrate intake could induce metabolic syndrome (MetS) in male rats with marked cardiac functional abnormalities. In addition, studies mentioned some benefits of insulin application on these complications, but there are considerable disagreements among their findings. Therefore, we aimed to extend our knowledge on the in-vitro influence of insulin on left ventricular dysfunction and also in the isolated cardiomyocytes from MetS rats. RESULTS: At the organ function level, an acute insulin application (100-nM) provided an important beneficial effect on the left ventricular developed pressure in MetS rats. Furthermore, to treat the freshly isolated cardiomyocytes from MetS rats with insulin provided marked recoveries in elevated resting intracellular Ca2+-level, as well as significant prevention of prolonged action potential through an augmentation in depressed K+-channel currents. Insulin also normalized the cellular levels of increased ROS and phosphorylation of PKCα, together with normalizations of apoptotic markers in MetS cardiomyocytes through the insulin-mediated regulation of phospho-Akt. Since not only elevated PKCα-activity but also reductions in phospho-Akt are key modulators of titin-based cardiomyocyte stiffening in hyperglycemia, insulin treatment of the cardiomyocytes prevented the activation of titin via the above pathways. Furthermore, CK2α-activation and NOS-phosphorylation could be prevented with insulin treatment. Mechanistically, we found that impaired insulin signaling and elevated PKCα and CK2α activities, as well as depressed Akt phosphorylation, are key modulators of titin-based cardiomyocyte stiffening in MetS rats. CONCLUSION: We propose that restoring normal kinase activities and also increases in phospho-Akt by insulin can contribute marked recoveries in MetS heart function, indicating a promising approach to modulate titin-associated factors in heart dysfunction associated with type-2 diabetes mellitus. Graphical Abstract.


Subject(s)
Casein Kinase II/metabolism , Connectin/metabolism , Hypoglycemic Agents/pharmacology , Insulin Resistance , Insulin/pharmacology , Metabolic Syndrome/drug therapy , Myocytes, Cardiac/drug effects , Ventricular Dysfunction, Left/drug therapy , Ventricular Function, Left/drug effects , Action Potentials/drug effects , Animals , Calcium Signaling/drug effects , Disease Models, Animal , Isolated Heart Preparation , Male , Metabolic Syndrome/enzymology , Metabolic Syndrome/physiopathology , Myocytes, Cardiac/enzymology , Oxidative Stress/drug effects , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Rats, Wistar , Ventricular Dysfunction, Left/enzymology , Ventricular Dysfunction, Left/physiopathology , Ventricular Pressure/drug effects
6.
J Pharm Pharm Sci ; 23(1): 65-74, 2020.
Article in English | MEDLINE | ID: mdl-32310756

ABSTRACT

Gamma glutamyl transferase (GGT) is an enzyme in glutathione and cysteine metabolism. GGT is a standard liver enzyme test reflecting biliary tract involvement. It also has a prooxoidant activity and a modulating influence on endothelia dysfunction. GGT is associated with the metabolic syndrome and is often elevated in patients with NAFLD. There is also a role for GGT activity in several aspects cardiovascular disease. There is an association between elevated GGT and cardiovascular mortality, atrial fibrillation, exacerbation of congestive heart failure . In addition there is an association with obstructive sleep apnea. We review the evidence available and suggest that there is a need for further assessing the use of GGT, together with the presence of the metabolic syndrome as a prognostic marker.


Subject(s)
Cardiovascular Diseases/enzymology , Metabolic Syndrome/enzymology , gamma-Glutamyltransferase/metabolism , Biomarkers/metabolism , Humans
7.
Lipids Health Dis ; 19(1): 102, 2020 May 21.
Article in English | MEDLINE | ID: mdl-32438926

ABSTRACT

BACKGROUND: The aim was to investigate if fatty acid profile and estimated desaturase activities; stearoyl CoA-desaturase (SCD), delta-5-desaturase and delta-6-desaturase (D5D; D6D), differ between individuals with metabolically healthy (MH) and unhealthy (MU) phenotypes. We also explored these associations according to BMI categories. METHODS: Men and women at moderately elevated risk of cardiovascular disease were included in this cross-sectional study (n = 321). If subjects met ≥4 out of 5 criteria (elevated triglycerides, total and LDL-cholesterol, HbA1c and low HDL-cholesterol), they were classified as MU (n = 52). If levels were within reference ranges for ≥3 of the same criteria, subjects were classified as MH (n = 150). Utilizing the entire population, a score ranging from 0 to 5 denoting the number of MU criteria met was computed. Estimated desaturase activities were calculated as product-to-precursor ratio of fatty acids in whole blood (SCD16 [16:1n7/16:0], SCD18 [18:1n9/18:0], D5D [18:3n6/18:2n6], D6D [20:4n6/20:3n6]). RESULTS: Individuals with MH had lower estimated SCD16 and SCD18 activities, whereas estimated D6D activity was higher compared to MU. Similar, SCD16 and SCD18 increased, whereas D6D decreased with increasing criteria of MU. Trends were similar across BMI categories. CONCLUSIONS: This study supports the notion of estimated desaturase activities as possible novel biomarkers of metabolic health irrespectively of BMI.


Subject(s)
Cholesterol, LDL/blood , Fatty Acid Desaturases/blood , Metabolic Syndrome/blood , Stearoyl-CoA Desaturase/blood , Triglycerides/blood , Aged , Cross-Sectional Studies , Delta-5 Fatty Acid Desaturase , Fatty Acid Desaturases/metabolism , Fatty Acids/metabolism , Female , Humans , Male , Metabolic Syndrome/enzymology , Middle Aged , Stearoyl-CoA Desaturase/metabolism
8.
Molecules ; 25(12)2020 Jun 21.
Article in English | MEDLINE | ID: mdl-32575811

ABSTRACT

Metabolic syndrome includes a cluster of risk factors for many pathological conditions, including hyperglycemia, abdominal obesity, hyperlipidemia, and hypertension. Adansonia digitata L. (also known as baobab) is used in traditional African Medicine and recent studies showed that it improves the metabolism of carbohydrates and lipids. The aim of this study is to investigate the mechanisms of action associated with the beneficial effects of extracts from the edible parts of baobab (fruit pulp, leaves, raw and toasted seeds), evaluating their inhibitory activity against: alpha-amylase, alpha-glucosidase, angiotensin-converting enzyme, 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, and pancreatic lipase. Baobab fruit pulp and leaf extracts resulted to be the most active ones and were then tested on the differentiation process of SW-872 human liposarcoma cells to mature adipocytes. The addition of these latter extracts did not affect triglyceride accumulation, indicating a neutral impact on this parameter. The findings here reported help to explain the growing amount of evidence on the biological properties of baobab and provide suggestions about their use in food and nutraceutical fields.


Subject(s)
Adansonia/chemistry , Cell Differentiation/drug effects , Metabolic Syndrome/drug therapy , Plant Extracts/chemistry , Plant Extracts/pharmacology , Adipocytes/drug effects , Angiotensin-Converting Enzyme Inhibitors/pharmacology , Cell Line, Tumor , Cell Survival/drug effects , Fruit/chemistry , Glycoside Hydrolase Inhibitors/pharmacology , Humans , Hydroxymethylglutaryl-CoA Reductase Inhibitors/pharmacology , Kaempferols/chemistry , Kaempferols/pharmacology , Lipase/antagonists & inhibitors , Metabolic Syndrome/enzymology , Molecular Docking Simulation , Plant Leaves/chemistry , Quercetin/analogs & derivatives , Quercetin/chemistry , Quercetin/pharmacology , Rutin/chemistry , Rutin/pharmacology , Seeds/chemistry , alpha-Amylases/antagonists & inhibitors
9.
Crit Rev Biochem Mol Biol ; 52(5): 543-553, 2017 10.
Article in English | MEDLINE | ID: mdl-28618839

ABSTRACT

Over 20 years ago, sphingosine-1-phosphate (S1P) was discovered to be a bioactive signaling molecule. Subsequent studies later identified two related kinases, sphingosine kinase 1 and 2, which are responsible for the phosphorylation of sphingosine to S1P. Many stimuli increase sphingosine kinase activity and S1P production and secretion. Outside the cell, S1P can bind to and activate five S1P-specific G protein-coupled receptors (S1PR1-5) to regulate many important cellular and physiological processes in an autocrine or paracrine manner. S1P is found in high concentrations in the blood where it functions to control vascular integrity and trafficking of lymphocytes. Obesity increases blood S1P levels in humans and mice. With the world wide increase in obesity linked to consumption of high-fat, high-sugar diets, S1P is emerging as an accomplice in liver pathobiology, including acute liver failure, metabolic syndrome, control of blood lipid and glucose homeostasis, nonalcoholic fatty liver disease, and liver fibrosis. Here, we review recent research on the importance of sphingosine kinases, S1P, and S1PRs in liver pathobiology, with a focus on exciting insights for new therapeutic modalities that target S1P signaling axes for a variety of liver diseases.


Subject(s)
Liver Diseases/metabolism , Liver/metabolism , Lysophospholipids/metabolism , Phosphotransferases (Alcohol Group Acceptor)/metabolism , Sphingosine/analogs & derivatives , Animals , Fatty Liver/enzymology , Fatty Liver/pathology , Humans , Liver/enzymology , Liver/pathology , Liver Diseases/enzymology , Liver Failure/enzymology , Liver Failure/pathology , Metabolic Syndrome/enzymology , Metabolic Syndrome/pathology , Sphingosine/metabolism
10.
Arterioscler Thromb Vasc Biol ; 38(8): 1785-1795, 2018 08.
Article in English | MEDLINE | ID: mdl-29903737

ABSTRACT

Objective- The E3 ubiquitin ligase IDOL (inducible degrader of the LDLR [LDL (low-density lipoprotein) receptor]) is a post-transcriptional regulator of LDLR abundance. Model systems and human genetics support a role for IDOL in regulating circulating LDL levels. Whether IDOL plays a broader metabolic role and affects development of metabolic syndrome-associated comorbidities is unknown. Approach and Results- We studied WT (wild type) and Idol(-/-) (Idol-KO) mice in 2 models: physiological aging and diet-induced obesity. In both models, deletion of Idol protected mice from metabolic dysfunction. On a Western-type diet, Idol loss resulted in decreased circulating levels of cholesterol, triglycerides, glucose, and insulin. This was accompanied by protection from weight gain in short- and long-term dietary challenges, which could be attributed to reduced hepatosteatosis and fat mass in Idol-KO mice. Although feeding and intestinal fat uptake were unchanged in Idol-KO mice, their brown adipose tissue was protected from lipid accumulation and had elevated expression of UCP1 (uncoupling protein 1) and TH (tyrosine hydroxylase). Indirect calorimetry indicated a marked increase in locomotion and suggested a trend toward increased cumulative energy expenditure and fat oxidation. An increase in in vivo clearance of reconstituted lipoprotein particles in Idol-KO mice may sustain this energetic demand. In the BXD mouse genetic reference population, hepatic Idol expression correlates with multiple metabolic parameters, thus providing support for findings in the Idol-KO mice. Conclusions- Our study uncovers an unrecognized role for Idol in regulation of whole body metabolism in physiological aging and on a Western-type diet. These findings support Idol inhibition as a therapeutic strategy to target multiple metabolic syndrome-associated comorbidities.


Subject(s)
Diet, High-Fat , Energy Metabolism , Liver/enzymology , Metabolic Syndrome/prevention & control , Obesity/prevention & control , Ubiquitin-Protein Ligases/deficiency , Adipogenesis , Adipose Tissue, Brown/enzymology , Adiposity , Age Factors , Aging , Animals , Biomarkers/blood , Blood Glucose/metabolism , Cholesterol/blood , Disease Models, Animal , Female , Insulin/blood , Locomotion , Male , Metabolic Syndrome/blood , Metabolic Syndrome/enzymology , Metabolic Syndrome/genetics , Mice, Inbred C57BL , Mice, Inbred DBA , Mice, Knockout , Obesity/blood , Obesity/enzymology , Obesity/genetics , Triglycerides/blood , Tyrosine 3-Monooxygenase/metabolism , Ubiquitin-Protein Ligases/genetics , Uncoupling Protein 1/metabolism
11.
BMC Endocr Disord ; 19(1): 100, 2019 Oct 15.
Article in English | MEDLINE | ID: mdl-31615498

ABSTRACT

BACKGROUND: Abnormal levels of liver enzymes, particularly aminotransferases, are prognostic features of non-alcoholic fatty liver disease (NAFLD). Considering the important role of dietary intakes in development of NAFLD, we aimed to determine possible association of unhealthy foods (fast foods, soft drinks, sweet and salty snacks) consumption with elevated levels of aminotransferases. METHODS: This cross-sectional study was conducted within the framework of sixth phase of the Tehran Lipid and Glucose Study (2014-2017), on 187 adult men and 249 adult women (19-70 y). Usual intakes of unhealthy foods (kcal/week) were measured using a validated semi-quantitative 147-items food frequency questionnaire. Serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) were measured. Multivariable logistic regression models were used to estimate the odds of elevated aminotransferases in each tertile of energy-dense unhealthy foods. RESULTS: Mean age of participants was 44.44 ± 15.09 years, 43% of participants were men. Higher consumption of fast foods (> 11.39% kcal/week) was associated with elevated ALT to AST ratio (OR: 3.27; 95% CI: 1.90-5.63) and elevated ALT (OR: 2.74; 95% CI: 1.57-4.76). Also, each 1 SD increased energy intakes from fast foods was related to increased chance of having elevated ALT and ALT to AST ratio by 35% (OR: 1.35; 95% CI: 1.08-1.68, OR: 1.35; 95% CI: 1.10-1.66, respectively). There was no significant association between consumption of soft drinks, sweet or salty snacks and elevated aminotransferases. CONCLUSIONS: Higher intakes of energy from fast foods seems to be associated with an elevated serum levels of ALT and ALT to AST ratio, as indicators of development of NAFLD.


Subject(s)
Alanine Transaminase/blood , Aspartate Aminotransferases/blood , Blood Glucose/analysis , Diet/adverse effects , Lipids/blood , Metabolic Syndrome/diagnosis , Adult , Biomarkers/analysis , Cross-Sectional Studies , Female , Follow-Up Studies , Food Preferences , Humans , Male , Metabolic Syndrome/blood , Metabolic Syndrome/enzymology , Metabolic Syndrome/etiology , Middle Aged , Prognosis , Risk Factors
12.
Nature ; 494(7437): 375-9, 2013 Feb 21.
Article in English | MEDLINE | ID: mdl-23354051

ABSTRACT

Insulin resistance is a fundamental pathogenic factor present in various metabolic disorders including obesity and type 2 diabetes. Although skeletal muscle accounts for 70-90% of insulin-stimulated glucose disposal, the mechanism underlying muscle insulin resistance is poorly understood. Here we show in mice that muscle-specific mitsugumin 53 (MG53; also called TRIM72) mediates the degradation of the insulin receptor and insulin receptor substrate 1 (IRS1), and when upregulated, causes metabolic syndrome featuring insulin resistance, obesity, hypertension and dyslipidaemia. MG53 expression is markedly elevated in models of insulin resistance, and MG53 overexpression suffices to trigger muscle insulin resistance and metabolic syndrome sequentially. Conversely, ablation of MG53 prevents diet-induced metabolic syndrome by preserving the insulin receptor, IRS1 and insulin signalling integrity. Mechanistically, MG53 acts as an E3 ligase targeting the insulin receptor and IRS1 for ubiquitin-dependent degradation, comprising a central mechanism controlling insulin signal strength in skeletal muscle. These findings define MG53 as a novel therapeutic target for treating metabolic disorders and associated cardiovascular complications.


Subject(s)
Carrier Proteins/metabolism , Insulin Resistance/physiology , Insulin , Metabolic Syndrome/metabolism , Ubiquitin-Protein Ligases/metabolism , Animals , Carrier Proteins/genetics , Diabetes Mellitus, Type 2 , Diet, High-Fat , Dyslipidemias/metabolism , Gene Deletion , Hypertension/metabolism , Insulin/metabolism , Insulin Receptor Substrate Proteins/metabolism , Insulin Resistance/genetics , Male , Membrane Proteins , Metabolic Syndrome/enzymology , Metabolic Syndrome/genetics , Metabolic Syndrome/prevention & control , Mice , Obesity/chemically induced , Obesity/metabolism , Rats , Rats, Inbred SHR , Rats, Inbred WKY , Receptor, Insulin/metabolism , Signal Transduction , Ubiquitination
13.
Can J Physiol Pharmacol ; 97(11): 1064-1072, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31299169

ABSTRACT

Metabolic syndrome (MetS) is a cluster of risk factors, including insulin resistance among others, underlying the development of diabetes and (or) cardiovascular diseases. Studies show a close relationship between cardiac dysfunction and abnormal cAMP catabolism, which contributes to pathological remodelling. Stimulating the synthesis of cAMP via suppression of phosphodiesterases (PDEs) has positive therapeutic effects. Therefore, we examined the role of PDEs on cardiac dysfunction in high-carbohydrate diet-induced MetS rats. We first demonstrated significantly high expression levels of PDE3 and PDE4, the most highly expressed subtypes, together with depressed cAMP levels in heart tissue from MetS rats. Second, we demonstrated the activity of these PDEs by using either their basal or PDE inhibitor-induced intracellular levels of cAMP and Ca2+, the transient intracellular Ca2+ changes under electrical stimulation, isometric contractions in papillary muscle strips and some key signalling proteins (such as RyR2, PLN, PP1A, and PKA) are responsible for the Ca2+ homeostasis in isolated cardiomyocytes from MetS rats. The clear recovery in decreased basal cAMP levels, increased protein expression levels of PDE3 and PDE4, and positive responses in the altered Ca2+ homeostasis to PDE inhibitors as seen in our study can provide important insights about the roles of activated PDEs in depressed contractile activity in hearts from MetS rats.


Subject(s)
Cyclic Nucleotide Phosphodiesterases, Type 3/metabolism , Cyclic Nucleotide Phosphodiesterases, Type 4/metabolism , Dietary Carbohydrates/adverse effects , Heart/drug effects , Heart/physiopathology , Metabolic Syndrome/chemically induced , Metabolic Syndrome/physiopathology , Animals , Cyclic AMP/metabolism , Dose-Response Relationship, Drug , Gene Expression Regulation, Enzymologic/drug effects , Metabolic Syndrome/enzymology , Muscle Contraction/drug effects , Phosphodiesterase Inhibitors/pharmacology , Rats
14.
Proc Natl Acad Sci U S A ; 113(20): 5754-9, 2016 May 17.
Article in English | MEDLINE | ID: mdl-27140617

ABSTRACT

Metabolic syndrome is characterized by insulin resistance, obesity, and dyslipidemia. It is the consequence of an imbalance between caloric intake and energy consumption. Adiponectin protects against metabolic syndrome. Insulin-induced signaling includes activation of PI3 kinase and protein kinase B (PKB)/Akt. PKB/Akt in turn inactivates glycogen synthase kinase (GSK) 3, a major regulator of metabolism. Here, we studied the significance of PI3K-dependent GSK3 inactivation for adiponectin formation in diet-induced metabolic syndrome. Mice expressing PI3K-insensitive GSK3 (gsk3(KI)) and wild-type mice (gsk3(WT)) were fed a high-fat diet. Compared with gsk3(WT) mice, gsk3(KI) mice were protected against the development of metabolic syndrome as evident from a markedly lower weight gain, lower total body and liver fat accumulation, better glucose tolerance, stronger hepatic insulin-dependent PKB/Akt phosphorylation, lower serum insulin, cholesterol, and triglyceride levels, as well as higher energy expenditure. Serum adiponectin concentration and the activity of transcription factor C/EBPα controlling the expression of adiponectin in adipose tissue was significantly higher in gsk3(KI) mice than in gsk3(WT) mice. Treatment with GSK3 inhibitor lithium significantly decreased the serum adiponectin concentration of gsk3(KI) mice and abrogated the difference in C/EBPα activity between the genotypes. Taken together, our data demonstrate that the expression of PI3K-insensitive GSK3 stimulates the production of adiponectin and protects from diet-induced metabolic syndrome.


Subject(s)
Adiponectin/biosynthesis , Glycogen Synthase Kinase 3/physiology , Metabolic Syndrome/enzymology , Adipose Tissue/metabolism , Animals , CCAAT-Enhancer-Binding Proteins/metabolism , Diet, High-Fat/adverse effects , Glucose Intolerance/enzymology , Insulin Resistance , Liver/enzymology , Male , Metabolic Syndrome/etiology , Mice, Transgenic , PTEN Phosphohydrolase/metabolism , Phosphatidylinositol 3-Kinases/physiology
15.
Int J Mol Sci ; 20(23)2019 Nov 22.
Article in English | MEDLINE | ID: mdl-31771123

ABSTRACT

Equine metabolic syndrome (EMS) is a cluster of metabolic disorders, such as obesity, hyperinsulinemia, and hyperleptinemia, as well as insulin resistance (IR). In accordance with the theory linking obesity and IR, excessive accumulation of lipids in insulin-sensitive tissues (lipotoxicity), like liver, alters several cellular functions, including insulin signaling. Therefore, the purpose of the study was to isolate equine hepatic progenitor-like cells (HPCs) and assess whether inhibition of low molecular weight protein tyrosine phosphatase (LMPTP) affects the expression of genes involved in macroautophagy, chaperone-mediated autophagy (CMA), endoplasmic reticulum stress, and mitochondrial dynamics in a palmitate-induced IR model. We demonstrated that LMPTP inhibition significantly enhanced expression of heat shock cognate 70 kDa protein (HSC70), lysosome-associated membrane protein 2 (LAMP2), and parkin (PRKN), all master regulators of selective autophagy. We also observed downregulation of C/EBP homologous protein (CHOP), activating transcription factor 6 (ATF6) and binding immunoglobulin protein encoded by the HSPA gene. Moreover, LMPTP inhibition increased alternative splicing of X-box binding protein 1 (XBP1), suggesting high endonuclease activity of inositol-requiring enzyme 1 alpha (IRE1α). Taken together, our data provide convincing evidence that LMPTP inhibition reverses palmitate-induced insulin resistance and lipotoxicity. In conclusion, this study highlights the role of LMPTP in the regulation of CMA, mitophagy, and ER stress, and provides a new in vitro model for studying HPC lipotoxicity in pre-clinical research.


Subject(s)
Autophagic Cell Death , Endoplasmic Reticulum Stress , Horse Diseases/enzymology , Liver/enzymology , Metabolic Syndrome/enzymology , Protein Tyrosine Phosphatases/metabolism , Stem Cells/enzymology , Animals , Horse Diseases/pathology , Horses , Insulin Resistance , Liver/pathology , Metabolic Syndrome/pathology , Palmitic Acid/toxicity , Stem Cells/pathology
16.
Molecules ; 24(18)2019 Sep 12.
Article in English | MEDLINE | ID: mdl-31547424

ABSTRACT

The Argentinean Patagonia berries Berberis microphylla, Berberis darwinii, and Fragaria chiloensis ssp. chiloensis f. patagonica were investigated for their polyphenol content and composition by means of liquid chromatography coupled to diode array detection and electrospray ionization tandem mass spectrometry. The in vitro antioxidant activity and inhibition of metabolic syndrome-associated enzymes (α-glucosidase, α-amylase, and lipase) of the fruit extracts was assessed. The most complex polyphenol profile was found in the Berberis samples, with 10 anthocyanins, 27 hydroxycinnamic acids, 3 proanthocyanidins, 2 flavan-3-ol, and 22 flavonols. Fragaria presented four anthocyanins, nine ellagitannins, two proanthocyanidin dimers, one flavan-3-ol, and five flavonols. The Berberis samples showed the best antioxidant capacity, while Fragaria displayed better activity against α-glucosidase and lipase. The phenolic content and composition of the Argentinean Patagonia berries was similar to that reported for Chilean samples but with some chemical differences between Eastern (Argentina) and Western (Chile) Patagonia. The data obtained supports the consumption of these berries as sources of beneficial polyphenols.


Subject(s)
Antioxidants/pharmacology , Berberis/chemistry , Fragaria/chemistry , Polyphenols/analysis , Polyphenols/pharmacology , Anthocyanins/analysis , Antioxidants/analysis , Argentina , Chromatography, High Pressure Liquid , Coumaric Acids/analysis , Glycoside Hydrolase Inhibitors/pharmacology , Humans , Hydrolyzable Tannins/analysis , Metabolic Syndrome/enzymology , Plant Extracts/analysis , Plant Extracts/pharmacology , Spectrometry, Mass, Electrospray Ionization , alpha-Amylases/antagonists & inhibitors
17.
Molecules ; 24(4)2019 Feb 13.
Article in English | MEDLINE | ID: mdl-30781736

ABSTRACT

Hawk tea is a rich and edible resource, traditionally used as a beverage in South China. This drink has many pharmacologic effects, such as acting as an antioxidant and reducing blood sugar and lipids. The objective of this work was to explore the active compound contents, bioactivities and their monthly changes, and optimize the harvest time. In the present study, Hawk tea from each month in 2017 was collected and extracted with 70% (v/v) ethanol. The contents of the total flavonoids and total phenols were determined using the colorimetric method. We determined the contents of seven characteristic active substances-hyperin, isoquercitrin, trifolin, quercitrin, astragalin, quercetin, and kaempferol-using high-performance liquid chromatography. The crude extract was tested for its antioxidant and inhibitory properties on enzymes involved in metabolic syndrome. Specifically, 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid), ferric-reducing power assay, and the inhibition capacity test on α-glucosidase and lipase were conducted to determine the antioxidant effect in vitro, as well as the reduction of blood sugar and lipids. Monthly variations in activities and components were determined by numeric analysis and comparison. Correlation analysis revealed that antioxidant effects are significantly correlated with the total flavonoids. The hierarchical cluster analysis of bioactivities and their contents indicates that October and November are the best harvesting months, which differs with the habitual collection of Hawk tea.


Subject(s)
Antioxidants/chemistry , Drugs, Chinese Herbal/chemistry , Metabolic Syndrome/diet therapy , Tea/chemistry , Antioxidants/administration & dosage , China , Drugs, Chinese Herbal/administration & dosage , Flavonoids/chemistry , Glycoside Hydrolase Inhibitors/administration & dosage , Glycoside Hydrolase Inhibitors/chemistry , Humans , Lipase/antagonists & inhibitors , Lipase/chemistry , Metabolic Syndrome/enzymology , Phenols/chemistry , Plant Leaves/chemistry , alpha-Glucosidases/chemistry , alpha-Glucosidases/drug effects
18.
J Sci Food Agric ; 99(6): 2939-2946, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30471120

ABSTRACT

BACKGROUND: Raspberry and strawberry are high value-added food products that can contribute to human health due to the abundance of polyphenols that they contain. Polyphenols are secondary metabolites and therefore devoted to improve plant adaptation, these polyphenol profile can be induced applying different stimuli, such as certain bacteria. The aim of this study was twofold: (i) to evaluate the ability of two bacterial strains to modulate secondary metabolisms in strawberry and raspberry, and (ii) to explore the ability of plant extracts to modify enzyme activities related to metabolic syndrome. RESULTS: Total phenolic and anthocyanin content was higher in strawberries than in raspberries, despite similar antioxidant capacities. Strawberry extracts performed better on the tested enzymes, except on α-glucosidase inhibition capacity. Bacillus amyloliquefaciens stabilized the effects of extracts at different points in time, and Pseudomonas fluorescens modified plant metabolism after more inoculations (spring) in both species, improving the effects of raspberry extracts on α-glucosidase, COX1, and COX2, and of strawberry on α-amylase and COX1. CONCLUSION: It is good to include these two fruits in the diet because they improve the activity of metabolic syndrome-related enzymes. Applying either strain during plant growth modifies the bioactive profile of the plants, improving the effects of the fruit extracts on human health. © 2018 Society of Chemical Industry.


Subject(s)
Fragaria/metabolism , Fruit/microbiology , Metabolic Syndrome/enzymology , Plant Extracts/chemistry , Rubus/metabolism , Anthocyanins/chemistry , Anthocyanins/metabolism , Bacillus amyloliquefaciens/metabolism , Cyclooxygenase 1/chemistry , Cyclooxygenase 1/metabolism , Cyclooxygenase 2/chemistry , Cyclooxygenase 2/metabolism , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/metabolism , Fragaria/microbiology , Fruit/chemistry , Fruit/metabolism , Humans , Metabolic Syndrome/diet therapy , Phenols/chemistry , Phenols/metabolism , Plant Extracts/metabolism , Pseudomonas fluorescens/metabolism , Rubus/chemistry , Rubus/microbiology , alpha-Amylases/genetics , alpha-Amylases/metabolism , alpha-Glucosidases/chemistry , alpha-Glucosidases/metabolism
19.
Bull Exp Biol Med ; 167(5): 698-701, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31630301

ABSTRACT

The expression of JNK1 isoform of cJun-N-terminal kinase in hepatocytes of rats receiving excess of simple carbohydrates dissolved in drinking water was studied by immunohisto-chemical staining and confocal microscopy. In experiment I (60 days), the highest expression of JNK1 was observed in female Wistar rats receiving fructose (the difference with the group receiving a mixture of glucose and fructose was significant, p<0.05, the difference with the control group at the trend level, p=0.077; Mann-Whitney U test). In experiment II (120 days), an increase in JNK1 expression was observed in Wistar rats (males and females) receiving 30% fructose. In Dark Aguti rats (females and males) of comparable age, increased basal level of JNK1 expression was observed in comparison with Wistar rats. Three-way ANOVA showed that JNK1 expression was significantly (p<0.05) associated with consumption of fructose and animal line, but not sex. The level of JNK1 expression corresponded to previously identified changes in the biochemical markers of the metabolic syndrome.


Subject(s)
Diet, Carbohydrate Loading , Fructose/metabolism , Glucose/metabolism , Hepatocytes/drug effects , Metabolic Syndrome/genetics , Mitogen-Activated Protein Kinase 8/genetics , Animals , Female , Fructose/administration & dosage , Gene Expression Regulation , Glucose/administration & dosage , Hepatocytes/enzymology , Liver/drug effects , Liver/enzymology , Male , Metabolic Syndrome/chemically induced , Metabolic Syndrome/enzymology , Metabolic Syndrome/pathology , Microscopy, Confocal , Mitogen-Activated Protein Kinase 8/metabolism , Rats , Rats, Inbred Strains , Rats, Wistar , Species Specificity
20.
J Mol Cell Cardiol ; 117: 88-99, 2018 04.
Article in English | MEDLINE | ID: mdl-29428638

ABSTRACT

Arterial stiffness plays a causal role in development of systolic hypertension. 20-hydroxyeicosatetraeonic acid (20-HETE), a cytochrome P450 (CYP450)-derived arachidonic acid metabolite, is known to be elevated in resistance arteries in hypertensive animal models and loosely associated with obesity in humans. However, the role of 20-HETE in the regulation of large artery remodeling in metabolic syndrome has not been investigated. We hypothesized that elevated 20-HETE in metabolic syndrome increases matrix metalloproteinase 12 (MMP12) activation leading to increased degradation of elastin, increased large artery stiffness and increased systolic blood pressure. 20-HETE production was increased ~7 fold in large, conduit arteries of metabolic syndrome (JCR:LA-cp, JCR) vs. normal Sprague-Dawley (SD) rats. This correlated with increased elastin degradation (~7 fold) and decreased arterial compliance (~75% JCR vs. SD). 20-HETE antagonists blocked elastin degradation in JCR rats concomitant with blocking MMP12 activation. 20-HETE antagonists normalized, and MMP12 inhibition (pharmacological and MMP12-shRNA-Lnv) significantly improved (~50% vs. untreated JCR) large artery compliance in JCR rats. 20-HETE antagonists also decreased systolic (182 ±â€¯3 mmHg JCR, 145 ±â€¯3 mmHg JCR + 20-HETE antagonists) but not diastolic blood pressure in JCR rats. Whereas diastolic pressure was fully angiotensin II (Ang II)-dependent, systolic pressure was only partially Ang II-dependent, and large artery stiffness was Ang II-independent. Thus, 20-HETE-dependent regulation of systolic blood pressure may be a unique feature of metabolic syndrome related to high 20-HETE production in large, conduit arteries, which results in increased large artery stiffness and systolic blood pressure. These findings may have implications for management of systolic hypertension in patients with metabolic syndrome.


Subject(s)
Blood Pressure , Hydroxyeicosatetraenoic Acids/metabolism , Hypertension/enzymology , Hypertension/physiopathology , Matrix Metalloproteinase 12/metabolism , Metabolic Syndrome/enzymology , Metabolic Syndrome/physiopathology , Vascular Stiffness , Animals , Collagen Type I/metabolism , Collagen Type III/metabolism , Compliance , Cytochrome P-450 CYP4A/metabolism , Cytochrome P450 Family 4/metabolism , Diastole/drug effects , Elastin/metabolism , Enzyme Activation/drug effects , Hypertension/complications , Losartan/pharmacology , Male , Metabolic Syndrome/complications , Proteolysis/drug effects , RNA, Small Interfering/metabolism , Rats, Sprague-Dawley , Vascular Stiffness/drug effects
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