1.My Sweetheart Is Broken: Role of Glucose in Diabetic Cardiomyopathy.
Manoja K BRAHMA ; Mark E PEPIN ; Adam R WENDE
Diabetes & Metabolism Journal 2017;41(1):1-9
Despite overall reductions in heart disease prevalence, the risk of developing heart failure has remained 2-fold greater among people with diabetes. Growing evidence has supported that fluctuations in glucose level and uptake contribute to cardiovascular disease (CVD) by modifying proteins, DNA, and gene expression. In the case of glucose, clinical studies have shown that increased dietary sugars for healthy individuals or poor glycemic control in diabetic patients further increased CVD risk. Furthermore, even after decades of maintaining tight glycemic control, susceptibility to disease progression can persist following a period of poor glycemic control through a process termed "glycemic memory." In response to chronically elevated glucose levels, a number of studies have identified molecular targets of the glucose-mediated protein posttranslational modification by the addition of an O-linked N-acetylglucosamine to impair contractility, calcium sensitivity, and mitochondrial protein function. Additionally, elevated glucose contributes to dysfunction in coupling glycolysis to glucose oxidation, pentose phosphate pathway, and polyol pathway. Therefore, in the "sweetened" environment associated with hyperglycemia, there are a number of pathways contributing to increased susceptibly to "breaking" the heart of diabetics. In this review we will discuss the unique contribution of glucose to heart disease and recent advances in defining mechanisms of action.
Calcium
;
Cardiomyopathies
;
Cardiovascular Diseases
;
Diabetic Cardiomyopathies*
;
Dietary Sucrose
;
Disease Progression
;
DNA
;
Gene Expression
;
Glucose*
;
Glycolysis
;
Heart
;
Heart Diseases
;
Heart Failure
;
Humans
;
Hyperglycemia
;
Metabolism
;
Mitochondrial Proteins
;
Pentose Phosphate Pathway
;
Prevalence
;
Protein Processing, Post-Translational
2.Changes in the Expression and Distribution of Claudins, Increased Epithelial Apoptosis, and a Mannan-Binding Lectin-Associated Immune Response Lead to Barrier Dysfunction in Dextran Sodium Sulfate-Induced Rat Colitis.
Bosi YUAN ; Shuping ZHOU ; Youke LU ; Jiong LIU ; Xinxin JIN ; Haijun WAN ; Fangyu WANG
Gut and Liver 2015;9(6):734-740
BACKGROUND/AIMS: This animal study aimed to define the underlying cellular mechanisms of intestinal barrier dysfunction. METHODS: Rats were fed 4% with dextran sodium sulfate (DSS) to induce experimental colitis. We analyzed the sugars in 24-hour urine output by high pressure liquid chromatography. The expression of claudins, mannan-binding lectin (MBL), and MBL-associated serine proteases 2 (MASP-2) were detected in the colonic mucosa by immunohistochemistry; and apoptotic cells in the colonic epithelium were detected by the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling method assay. RESULTS: The lactulose and sucralose excretion levels in the urine of rats with DSS-induced colitis were significantly higher than those in the control rats. Mannitol excretion was lower and lactulose/mannitol ratios and sucralose/mannitol ratios were significantly increased compared with those in the control group (p<0.05). Compared with the controls, the expression of sealing claudins (claudin 3, claudin 5, and claudin 8) was significantly decreased, but that of claudin 1 was increased. The expression of pore-forming claudin 2 was upregulated and claudin 7 was downregulated in DSS-induced colitis. The epithelial apoptotic ratio was 2.8%+/-1.2% in controls and was significantly increased to 7.2%+/-1.2% in DSS-induced colitis. The expression of MBL and MASP-2 in the intestinal mucosa showed intense staining in controls, whereas there was weak staining in the rats with colitis. CONCLUSIONS: There was increased intestinal permeability in DSS-induced colitis. Changes in the expression and distribution of claudins, increased epithelial apoptosis, and the MASP-2-induced immune response impaired the intestinal epithelium and contributed to high intestinal permeability.
Animals
;
Apoptosis/*physiology
;
Claudins/*metabolism
;
Colitis/chemically induced/immunology/*physiopathology
;
Colon/immunology/physiopathology
;
Dextran Sulfate
;
Intestinal Mucosa/*physiopathology
;
Lactulose/metabolism
;
Mannitol/metabolism
;
Mannose-Binding Lectin/*immunology
;
Permeability
;
Rats
;
Rats, Sprague-Dawley
;
Sucrose/analogs & derivatives/metabolism
;
Up-Regulation
3.Succinic acid production from sucrose and sugarcane molasses by metabolically engineered Escherichia coli.
Feng LI ; Jiangfeng MA ; Mingke WU ; Yaliang JI ; Wufang CHEN ; Xinyi REN ; Min JIANG
Chinese Journal of Biotechnology 2015;31(4):534-541
Sugarcane molasses containing large amounts of sucrose is an economical substrate for succinic acid production. However, Escherichia coli AFP111 cannot metabolize sucrose although it is a promising candidate for succinic acid production. To achieve sucrose utilizing ability, we cloned and expressed cscBKA genes encoding sucrose permease, fructokinase and invertase of non-PTS sucrose-utilization system from E. coli W in E. coli AFP111 to generate a recombinant strain AFP111/pMD19T-cscBKA. After 72 h of anaerobic fermentation of the recombinant in serum bottles, 20 g/L sucrose was consumed and 12 g/L succinic acid was produced. During dual-phase fermentation comprised of initial aerobic growth phase followed by anaerobic fermentation phase, the concentration of succinic acid from sucrose and sugarcane molasses was 34 g/L and 30 g/L, respectively, at 30 h of anaerobic phase in a 3 L fermentor. The results show that the introduction of non-PTS sucrose-utilization system has sucrose-metabolizing capability for cell growth and succinic acid production, and can use cheap sugarcane molasses to produce succinic acid.
Bioreactors
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Escherichia coli
;
genetics
;
metabolism
;
Escherichia coli Proteins
;
genetics
;
Fermentation
;
Membrane Transport Proteins
;
genetics
;
Metabolic Engineering
;
Molasses
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Saccharum
;
chemistry
;
Succinic Acid
;
chemistry
;
Sucrose
;
chemistry
4.Molecular cloning and over-expression of a fructosyltransferase from Aspergillus niger QU10.
Guoqing ZHANG ; Jing YANG ; Jiaji SHI ; Shijun QIAN ; Yapeng CHAO
Chinese Journal of Biotechnology 2015;31(4):512-522
The main commercial production of fructooligosaccharides (FOS) comes from enzymatic transformation using sucrose as substrate by microbial enzyme fructosyltransferase. A fructosyltransferase genomic DNA was isolated from Aspergillus niger QU10 by PCR. The nucleotide sequence showed a 1 941 bp size, and has been submitted to GenBank (KF699529). The cDNA of the fructosyltransferase, containing an open reading frame of 1 887 bp, was further cloned by RT-PCR. The fructosyltransferase gene from Aspergillus niger was functionally expressed both in Escherichia coli and Pichia pastoris GS 115. The highest activity value for the construction with the α-factor signal peptide reached 431 U/mL after 3 days of incubation. The recombinant enzyme is extensively glycosylated, and the active form is probably represented by a homodimer with an apparent molecular mass of 200 kDa as judged from mobility in seminative PAGE gels. The extracellular recombinant enzyme converted sucrose mostly to FOS, mainly 1-kestose and nystose, liberating glucose. FOS reached a maximal value and represented about 58% of total sugars present in the reaction mixture after 4 h reaction. The results suggest that the availability of recombinant Pichia pastoris as a new source of a FOS-producing enzyme might result of biotechnology interest for industrial application.
Aspergillus niger
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enzymology
;
genetics
;
Base Sequence
;
Cloning, Molecular
;
DNA, Complementary
;
Escherichia coli
;
Fungal Proteins
;
genetics
;
metabolism
;
Glycosylation
;
Hexosyltransferases
;
genetics
;
metabolism
;
Molecular Sequence Data
;
Molecular Weight
;
Pichia
;
Sucrose
;
metabolism
;
Trisaccharides
;
metabolism
5.Effect of exogenous sucrose on growth and active ingredient content of licorice seedlings under salt stress conditions.
China Journal of Chinese Materia Medica 2015;40(22):4384-4388
Licorice seedlings were taken as experimental materials, an experiment was conducted to study the effects of exogenous sucrose on growth and active ingredient content of licorice seedlings under NaCl stress conditions. The results of this study showed that under salt stress conditions, after adding a certain concentration of exogenous sucrose, the licorice seedlings day of relative growth rate was increasing, and this stress can be a significant weakening effect, indicating that exogenous sucrose salt stress-relieving effect. The total flavonoids and phenylalanine ammonia lyase (PAL) activity were significantly increased, the exogenous sucrose can mitigated the seedling roots under salt stress, the licorice flavonoid content in the enhanced growth was largely due to the activity of PAL an increased, when the concentration of exogenous sucrose wae 10 mmol x L(-1), PAL activity reaching a maximum, when the concentration of exogenous sucrose was 15 mmol x L(-1), PAL activity turned into a downward trend, the results indicating that this mitigation has concentration effect. After applying different concentrations of exogenous sugar, the contents of liquiritin changes with the change of flavonoids content was similar. After applying different concentrations of exogenous sucrose, the content of licorice acid under salt stress was higher than the levels were not reached during salt stress, the impact of exogenous sucrose concentration gradient of licorice acid accumulation was not obvious.
Drugs, Chinese Herbal
;
analysis
;
metabolism
;
Glycyrrhiza
;
chemistry
;
growth & development
;
metabolism
;
Plant Roots
;
chemistry
;
growth & development
;
metabolism
;
Seedlings
;
chemistry
;
growth & development
;
metabolism
;
Sodium Chloride
;
metabolism
;
Sucrose
;
metabolism
6.Metabolic activity of Streptococcus mutans biofilms and gene expression during exposure to xylitol and sucrose.
Eva-Maria DECKER ; Christian KLEIN ; Dimitri SCHWINDT ; Christiane von OHLE
International Journal of Oral Science 2014;6(4):195-204
The objective of the study was to analyse Streptococcus mutans biofilms grown under different dietary conditions by using multifaceted methodological approaches to gain deeper insight into the cariogenic impact of carbohydrates. S. mutans biofilms were generated during a period of 24 h in the following media: Schaedler broth as a control medium containing endogenous glucose, Schaedler broth with an additional 5% sucrose, and Schaedler broth supplemented with 1% xylitol. The confocal laser scanning microscopy (CLSM)-based analyses of the microbial vitality, respiratory activity (5-cyano-2,3-ditolyl tetrazolium chloride, CTC) and production of extracellular polysaccharides (EPS) were performed separately in the inner, middle and outer biofilm layers. In addition to the microbiological sample testing, the glucose/sucrose consumption of the biofilm bacteria was quantified, and the expression of glucosyltransferases and other biofilm-associated genes was investigated. Xylitol exposure did not inhibit the viability of S. mutans biofilms, as monitored by the following experimental parameters: culture growth, vitality, CTC activity and EPS production. However, xylitol exposure caused a difference in gene expression compared to the control. GtfC was upregulated only in the presence of xylitol. Under xylitol exposure, gtfB was upregulated by a factor of 6, while under sucrose exposure, it was upregulated by a factor of three. Compared with glucose and xylitol, sucrose increased cell vitality in all biofilm layers. In all nutrient media, the intrinsic glucose was almost completely consumed by the cells of the S. mutans biofilm within 24 h. After 24 h of biofilm formation, the multiparametric measurements showed that xylitol in the presence of glucose caused predominantly genotypic differences but did not induce metabolic differences compared to the control. Thus, the availability of dietary carbohydrates in either a pure or combined form seems to affect the cariogenic potential of S. mutans biofilms.
Bacterial Load
;
drug effects
;
Bacteriological Techniques
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Biofilms
;
drug effects
;
Cariogenic Agents
;
metabolism
;
pharmacology
;
Culture Media
;
Dental Enamel
;
microbiology
;
Fluorescent Dyes
;
Gene Expression Regulation, Bacterial
;
drug effects
;
Gene Expression Regulation, Enzymologic
;
drug effects
;
Genotype
;
Glucose
;
metabolism
;
Glucosyltransferases
;
metabolism
;
Humans
;
Microbial Viability
;
drug effects
;
Microscopy, Confocal
;
Polysaccharides, Bacterial
;
biosynthesis
;
Streptococcus mutans
;
drug effects
;
enzymology
;
metabolism
;
Sucrose
;
metabolism
;
pharmacology
;
Sweetening Agents
;
metabolism
;
pharmacology
;
Tetrazolium Salts
;
Time Factors
;
Up-Regulation
;
Xylitol
;
metabolism
;
pharmacology
7.Effect of hesperidin on behavior and HPA axis of rat model of chronic stress-induced depression.
Li CAI ; Rong LI ; Qing-Qing WU ; Ting-Ni WU
China Journal of Chinese Materia Medica 2013;38(2):229-233
OBJECTIVETo observe the effect of hesperidin on behavior and hypothalamic-pituitary-adrenal (HPA) axis of ratmodel of chronic stress-induced depression.
METHODChronic unpredictable mild stress (CUMS) was used to establish the rat depression model. Sixty male SD rats were divided randomly into six groups: the normal group, the model group, the hesperidin (40, 80, 160 mg x kg(-1)) group and the positive fluoxetine (10 mg x kg(-1)) group. They were orally administered with drugs for three weeks. The sucrose preference test and the forced swimming test (FST) were assayed to detect animal behavior. The levels of corticosterone (CORT) in serum, mRNA of corticotropin release factor (CRF) in hypothalamus as well as protein expression of glucocorticoid receptor (GR) in paraventricular nucleus (PVN) were determined to clarify the anti-depression effect and mechanism of hesperidin.
RESULTCompared with the model group, rats in the hesperidin (40, 80, 160 mg x kg(-1)) treatment group showed significant increase in the sucrose consumption and decrease in the immobility time in FST to varying degrees. Meanwhile, the excessively high serum CORT and adrenal index of CUMS rats were reversed by treatment with hesperidin. In addition, hesperidin inhibited CRF mRNA expression in hypothalamus and up-regulated GR protein expression in PVN among CUMS rats.
CONCLUSIONHesperidin could effectively improve the behavior of CUMS rats and show the anti-depression effect. Its mechanisms may be related to the function of regulating HPA axis.
Administration, Oral ; Animals ; Behavior, Animal ; drug effects ; Corticosterone ; blood ; Corticotropin-Releasing Hormone ; genetics ; metabolism ; Depression ; drug therapy ; etiology ; Fluoxetine ; administration & dosage ; Gene Expression Regulation ; drug effects ; Hesperidin ; administration & dosage ; pharmacology ; Hypothalamo-Hypophyseal System ; drug effects ; physiopathology ; Hypothalamus ; metabolism ; Male ; Models, Animal ; Pituitary-Adrenal System ; drug effects ; physiopathology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Receptors, Glucocorticoid ; metabolism ; Stress, Psychological ; complications ; drug therapy ; Sucrose ; metabolism ; Swimming ; Up-Regulation
8.Studies on adventitious root induction in vitro and suspension culture of Polygonum multiflorum.
He-Ping HUANG ; Shan-Lin GAO ; Jian WANG ; Lu-Qi HUANG ; Peng HUANG
China Journal of Chinese Materia Medica 2013;38(22):3857-3860
To achieve sustainable resources use of Polygonum multiflorum, adventitious roots were efficiently induced and cultured by suspension culture. In order to obtain optimal medium for induction adventitious roots from the young stems of P. multiflorum, MS medium was optimized by supplementing with different concentrations of sucrose and plant growth substances. The optimal medium for suspension culture of adventitious roots was determined by orthogonal design. The adventitious roots with suspension culture were subcultured, and the growth curve was also determined. Furthermore, the effective compound in adventitious roots was detected. The result indicated that the optimal medium for efficient induction of adventitious roots was MS medium containing 4% w/v sucrose, supplemented with 2.0 mg x L(-1) NAA, and 0.2 mg x L(-1) 6-BA. The optimal medium for suspension culture of adventitious roots was MS medium containing 3% sucrose, supplemented with 2.0 mg x L(-1) NAA, and 0.2 mg x L(-1) ABT-7.2,3,5,4'-tetrahydroxyl-diphenyl-ethylene-2-O-beta-D-glucoside was detected in adventitious roots, which was effective compound in medicinal material of P. multiflorum. In conclusion, the experiment achieved efficient induction and suspension culture of adventitious roots of P. multiflorum, and laid a foundation for the research on the sustainable use of traditional Chinese medicine resources.
Culture Media
;
chemistry
;
metabolism
;
Plant Growth Regulators
;
metabolism
;
Plant Roots
;
growth & development
;
metabolism
;
Polygonaceae
;
growth & development
;
metabolism
;
Sucrose
;
metabolism
;
Tissue Culture Techniques
;
methods
9.A review on gastric leptin: the exocrine secretion of a gastric hormone.
Philippe CAMMISOTTO ; Moise BENDAYAN
Anatomy & Cell Biology 2012;45(1):1-16
A major advance in the understanding of the regulation of food intake has been the discovery of the adipokine leptin a hormone secreted by the adipose tissue. After crossing the blood-brain barrier, leptin reaches its main site of action at the level of the hypothalamic cells where it plays fundamental roles in the control of appetite and in the regulation of energy expenditure. At first considered as a hormone specific to the white adipose tissue, it was rapidly found to be expressed by other tissues. Among these, the gastric mucosa has been demonstrated to secrete large amounts of leptin. Secretion of leptin by the gastric chief cells was found to be an exocrine secretion. Leptin is secreted towards the gastric lumen into the gastric juice. We found that while secretion of leptin by the white adipose tissue is constitutive, secretion by the gastric cells is a regulated one responding very rapidly to secretory stimuli such as food intake. Exocrine-secreted leptin survives the hydrolytic conditions of the gastric juice by forming a complex with its soluble receptor. This soluble receptor is synthesized by the gastric cells and the leptin-leptin receptor complex gets formed at the level of the gastric chief cell secretory granules before being released into the gastric lumen. The leptin-leptin receptor upon resisting the hydrolytic conditions of the gastric juice is channelled, to the duodenum. Transmembrane leptin receptors expressed at the luminal membrane of the duodenal enterocytes interact with the luminal leptin. Leptin is actively transcytosed by the duodenal enterocytes. From the apical membrane it is transferred to the Golgi apparatus where it binds again its soluble receptor. The newly formed leptin-leptin receptor complex is then secreted baso-laterally into the intestinal mucosa to reach the blood capillaries and circulation thus reaching the hypothalamus where its action regulates food intake. Exocrine-secreted gastric leptin participates in the short term regulation of food intake independently from that secreted by the adipose tissue. Adipose tissue leptin on the other hand, regulates in the long term energy storage. Both tissues work in tandem to ensure management of food intake and energy expenditure.
Adipokines
;
Adipose Tissue
;
Adipose Tissue, White
;
Appetite
;
Blood-Brain Barrier
;
Capillaries
;
Chief Cells, Gastric
;
Dietary Sucrose
;
Duodenum
;
Eating
;
Energy Metabolism
;
Enterocytes
;
Gastric Juice
;
Gastric Mucosa
;
Golgi Apparatus
;
Hand
;
Hypothalamus
;
Intestinal Mucosa
;
Leptin
;
Membranes
;
Phenobarbital
;
Receptors, Leptin
;
Secretory Vesicles
10.Properties of sucrose phosphorylase from recombinant Escherichia coli and enzymatic synthesis of alpha-arbutin.
Yuejia WAN ; Jiangfeng MA ; Rong XU ; Aiyong HE ; Min JIANG ; Kequan CHEN ; Yin JIANG
Chinese Journal of Biotechnology 2012;28(12):1450-1459
Sucrose phosphorylase (EC 2.4.1.7, Sucrose phosphorylase, SPase) can be produced by recombinant strain Escherichia coli Rosetta(DE3)/Pet-SPase. Crude enzyme was obtained from the cells by the high pressure disruption and centrifugation. Sucrose phosphorylase was purified by Ni-NTA affinity column chromatography and desalted by ultrafiltration. The specific enzyme activity was 1.1-fold higher than that of the crude enzyme, and recovery rate was 82.7%. The purified recombinant SPase had a band of 59 kDa on SDS-PAGE. Thermostability of the enzyme was shown at temperatures up to 37 degrees C, and pH stability between pH 6.0 and 6.7. The optimum temperature and pH were 37 degrees C and 6.7, respectively. The K(m) of SPase for sucrose was 7.3 mmol/L, and Vmax was 0.2 micromol/(min x mg). Besides, alpha-arbutin was synthesized from sucrose and hydroquinone by transglucosylation with recombinant SPase. The optimal conditions for synthesis of alpha-arbutin were 200 U/mL of recombinant SPase, 20% of sucrose, and 1.6% hydroquinone at pH 6-6.5 and 25 degrees C for 21 h. Under these conditions, alpha-arbutin was obtained with a 78.3% molar yield with respect to hydroquinone, and the concentration of alpha-arbutin was about 31 g/L.
Arbutin
;
biosynthesis
;
Catalysis
;
Enzyme Stability
;
Escherichia coli
;
enzymology
;
genetics
;
Glucosyltransferases
;
biosynthesis
;
genetics
;
metabolism
;
Hydroquinones
;
metabolism
;
Recombinant Proteins
;
biosynthesis
;
genetics
;
metabolism
;
Sucrose
;
metabolism

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