The effects of removing endogenous proteins, β-glucan and lipids on the surface microstructure, water migration and glucose diffusion in vitro of starch in highland barley flour

Abstract Background Cleome viscosa is considered as an important medicinal plant extensively used in India, China, Bangladesh, and a few countries in Africa. In the present study, in vitro anti-radical and antidiabetic potential of isolated fractions of methanolic extract of C. viscosa whole plant (MeCV) has been investigated. The identification of polyphenols and their related functional groups in the bioactive fraction was categorized by using HPLC and FT-IR. Results The total phenolic and flavonoid contents of F-D were higher than those of F-A, F-B, and F-C. The F-D exhibited superior antioxidant capacity when compared with the remaining three fractions. However, the F-D showed the highest glucose diffusion activity over the 30 min–27 h incubation period and also inhibited both α-glucosidase and α-amylase enzyme activity. HPLC analysis revealed the presence of the two known compounds (protocatechuic acid hexoside, rutin) and six unknown compounds in the F-D. FTIR spectrum confirmed the presence of phenol group. Conclusion The isolated F-D obtained from MeCV displayed superior antioxidant and antidiabetic activity which indicate the presence of polyphenols in the fraction. The data findings of the present study support the traditional uses of the whole plant of C. viscosa as a promising natural source of biological medicines for oxidative stress and diabetes.

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Assessment of the Nutritional Value, Techno-Functional, and In Vitro Physiological Properties of Six Edible Insects

Proceedings ◽

10.3390/foods_2020-08499 ◽

2020 ◽

Vol 70 (1) ◽

pp. 77

Author(s):

Yolanda Aguilera ◽

Miguel Rebollo-Hernanz ◽

Irene Pastrana ◽

Vanesa Benitez ◽

Gerardo Alvarez-Rivera ◽

...

Keyword(s):

Antioxidant Capacity ◽

Bulk Density ◽

Bile Salts ◽

Positive Impact ◽

Starch Hydrolysis ◽

Hydration Properties ◽

Physiological Properties ◽

Glucose Diffusion ◽

Foaming Capacity

The objective of this study was to evaluate the nutritional composition, techno-functional, and in vitro physiological properties of flours from six different insect species (mealworm, beetle, caterpillar, ant, locust, and cricket). The chemical composition of insects was evaluated following the standard methods (AOAC). Bulk density, water holding capacity, oil holding capacity, water absorption capacity, swelling capacity, emulsifying activity, foaming capacity, and gelation capacity were measured. In vitro antioxidant capacity was measured by the direct ABTS method. Hypoglycemic (glucose adsorption and the inhibition of α-amylase, glucose diffusion, and starch hydrolysis) and hypolipidemic (cholesterol and bile salts binding and lipase inhibition capacities) were investigated using in vitro methods. Insect flours exhibited a high content of protein (39.4%–58.1%) and fat (17.7%–50.1%) as main components, although the presence of chitin in ant samples was also highlighted. The techno-functional properties showed high oil holding, swelling, and emulsifying capacities in all insect flours analyzed, besides bulk density, hydration properties, and foaming capacity showing average values and no gelation capacity. Insects showed high antioxidant capacity (179–221 mg Trolox equivalents/g). Moreover, these edible insect flours revealed effective hyperglycemic and hyperlipidemic properties. Insect flours inhibited α-amylase activity (47.1%–98.0%) and retarded glucose diffusion (17.2%–29.6%) and starch hydrolysis (18.2%–88.1%). Likewise, they bound cholesterol and bile salts (8.4%–98.6%) and inhibited lipase activity (8.9%–47.1%). Hence, these insect flours might be of great interest to the food industry, being a healthy source of protein, exerting a positive impact on functional food properties, and potentially preventing the development of diseases associated with hyperglycemia and hyperlipidemia.

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14-3-3 Facilitates Insulin-Stimulated Intracellular Trafficking of Insulin Receptor Substrate 1

Molecular Endocrinology ◽

10.1210/mend.16.3.0790 ◽

2002 ◽

Vol 16 (3) ◽

pp. 552-562 ◽

Cited By ~ 17

Author(s):

Xiaoqin Xiang ◽

Mingsheng Yuan ◽

Ying Song ◽

Neil Ruderman ◽

Rong Wen ◽

...

Keyword(s):

Insulin Receptor ◽

Intracellular Trafficking ◽

High Speed ◽

Insulin Treatment ◽

Insulin Receptor Substrate ◽

Insulin Receptor Substrate 1 ◽

Integral Role ◽

Endogenous Proteins

Abstract The appearance of a complex between tyrosine-phosphorylated insulin receptor substrate 1 (IRS-1) and PI3K in a high-speed pellet fraction (HSP) is thought to be a key event in insulin action. Conversely, the disappearance of the IRS-1/PI3K complex from this fraction has been linked to insulin desensitization. The present study examines the role of 14-3-3, a specific phospho-serine binding protein, in mediating the disappearance of IRS-1 from the HSP after insulin treatment. An in vitro pull-down assay using recombinant 14-3-3 revealed that insulin enhances the association of 14-3-3 with IRS-1 in cultured adipocytes and that this is completely inhibited by wortmannin. An association of IRS-1 and 14-3-3 was also observed and was maximal after stimulation by insulin, when endogenous proteins were immunoprecipitated. Epidermal growth factor (EGF), 12-O-tetradecanoylphorbol-13-acetate, and okadaic acid, other agents that cause serine/threonine phosphorylation of IRS-1, also stimulated IRS binding to 14-3-3. The enhancement of IRS-1 binding to 14-3-3 by insulin was accompanied by movement of IRS-1 and the p85 subunit of PI3K from the HSP to the cytosol. In keeping with a key role of 14-3-3 in mediating this redistribution of IRS-1, the complexes of IRS-1 and 14-3-3 were found in the cytosol but not in the HSP of insulin-treated cells. In addition, colocalization of IRS-1 and 14-3-3 was observed in the cytoplasm after insulin treatment by confocal microscopy. Finally, the addition of a phosphorylated 14-3-3 binding peptide to an adipocyte homogenate (to remove 14-3-3 from IRS-1) increased the abundance of IRS-1/PI3K complexes in the HSP and decreased their abundance in the cytosol. These findings strongly suggest that 14-3-3 participates in the intracellular trafficking of IRS-1 by promoting the displacement of serine-phosphorylated IRS-1 from particular structures. They also suggest that 14-3-3 proteins could play an integral role in the process of insulin desensitization.

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Characterisation of the conformational changes in platelet factor 4 induced by polyanions: towards in vitro prediction of antigenicity

Thrombosis and Haemostasis ◽

10.1160/th13-08-0634 ◽

2014 ◽

Vol 112 (07) ◽

pp. 53-64 ◽

Cited By ~ 42

Author(s):

Sven Brandt ◽

Krystin Krauel ◽

Kay E. Gottschalk ◽

Thomas Renné ◽

Christiane A. Helm ◽

...

Keyword(s):

Conformational Changes ◽

Structural Changes ◽

Cd Spectroscopy ◽

Platelet Factor 4 ◽

Drug Induced ◽

Platelet Factor ◽

Preclinical Drug Development ◽

Varying Length ◽

Endogenous Proteins

SummaryHeparin-induced thrombocytopenia (HIT) is the most frequent drug-induced immune reaction affecting blood cells. Its antigen is formed when the chemokine platelet factor 4 (PF4) complexes with polyanions. By assessing polyanions of varying length and degree of sulfation using immunoassay and circular dichroism (CD)-spectroscopy, we show that PF4 structural changes resulting in antiparallel β-sheet content >30% make PF4/polyanion complexes antigenic. Further, we found that polyphosphates (polyP-55) induce antigenic changes on PF4, whereas fondaparinux does not. We provide a model suggesting that conformational changes exposing antigens on PF4/polyanion complexes occur in the hairpin involving AA 32–38, which form together with C-terminal AA (66–70) of the adjacent PF4 monomer a continuous patch on the PF4 tetramer surface, explaining why only tetrameric PF4 molecules express “HIT antigens”. The correlation of antibody binding in immunoassays with PF4 structural changes provides the intriguing possibility that CD-spectroscopy could become the first antibody-independent, in vitro method to predict potential immunogenicity of drugs. CD-spectroscopy could identify compounds during preclinical drug development that induce PF4 structural changes correlated with antigenicity. The clinical relevance can then be specifically addressed during clinical trials. Whether these findings can be transferred to other endogenous proteins requires further studies.

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IN VITRO HYPOGLYCEMIC EFFECTS OF CAESALPINIA BONDUCELLA AND MYRISTICA FRAGRANS SEED EXTRACTS

INDIAN DRUGS ◽

10.53879/id.55.02.11085 ◽

2018 ◽

Vol 55 (02) ◽

pp. 57-62

Author(s):

M. A Bhutkar ◽

◽

S. D Bhinge ◽

D. S. Randive ◽

G. H Wadkar ◽

...

Keyword(s):

Glucose Uptake ◽

Plant Extracts ◽

Glucose Concentration ◽

Yeast Cells ◽

In Vivo Models ◽

Myristica Fragrans ◽

Glucose Diffusion ◽

Caesalpinia Bonducella

The present investigation was undertaken to assess the hypoglycemic potential of Caesalpinia bonducella (C.bonducella) and Myristica fragrans (M.fragrans), employing various in vitro techniques. The extracts of seeds of C. bonducella and M. fragrans were studied for their effects on glucose adsorption capacity, in vitro glucose diffusion, in vitro amylolysis kinetics and glucose transport across the yeast cells. It was observed that the plant extracts under study adsorbed glucose and the adsorption of glucose increased remarkably with an increase in glucose concentration. There were no significant (p≤0.05) differences between their adsorption capacities. The results of amylolysis kinetic experimental model revealed that the rate of glucose diffusion was found to be increased with time from 30 to 180 min and both the plant extracts demonstrated significant inhibitory effects on movement of glucose into external solution across dialysis membrane as compared to control. Also, the plant extracts promoted glucose uptake by the yeast cells. It was observed that the enhancement of glucose uptake was dependent on both the sample and glucose concentration. C. bonducella extract exhibited significantly higher (p≤0.05) activity than the extract of M. fragrans at all concentrations. The results of the study verified the hypoglycemic activity of the extracts of C. bonducella and M. fragrans. However, the observed effects exhibited by the extracts of seeds of C. bonducella and M. fragrans need to be confirmed by using different in vivo models and clinical trials for their effective utilization as therapeutic agents in better management of diabetes mellitus.

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Quantitative Evaluation by Glucose Diffusion of Microleakage in Aged Calcium Silicate-Based Open-Sandwich Restorations

International Journal of Dentistry ◽

10.1155/2012/105863 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 29

Author(s):

S. Koubi ◽

H. Elmerini ◽

G. Koubi ◽

H. Tassery ◽

J. Camps

Keyword(s):

Calcium Silicate ◽

Glass Ionomer Cement ◽

Glass Ionomer ◽

Calcium Silicate Cement ◽

Resin Modified Glass Ionomer ◽

Glucose Diffusion ◽

Negative Controls ◽

Phosphate Buffered Saline ◽

Ionomer Cement

This study compared thein vitromarginal integrity of open-sandwich restorations based on aged calcium silicate cement versus resin-modified glass ionomer cement. Class II cavities were prepared on 30 extracted human third molars. These teeth were randomly assigned to two groups () to compare a new hydraulic calcium silicate cement designed for restorative dentistry (Biodentine, Septodont, Saint Maur des Fossés, France) with a resin-modified glass ionomer cement (Ionolux, Voco, Cuxhaven, Germany) in open-sandwich restorations covered with a light-cured composite. Positive () and negative () controls were included. The teeth simultaneously underwent thermocycling and mechanocycling using a fatigue cycling machine (1,440 cycles, 5–55°C; 86,400 cycles, 50 N/cm2). The specimens were then stored in phosphate-buffered saline to simulate aging. After 1 year, the teeth were submitted to glucose diffusion, and the resulting data were analyzed with a nonparametric Mann-Whitney test. The Biodentine group and the Ionolux group presented glucose concentrations of 0.074 ± 0.035 g/L and 0.080 ± 0.032 g/L, respectively. No statistically significant differences were detected between the two groups. Therefore, the calcium silicate-based material performs as well as the resin-modified glass ionomer cement in open-sandwich restorations.

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Antidiabetic Mechanisms of Rosa canina Fruits

Journal of Evidence-Based Complementary & Alternative Medicine ◽

10.1177/2156587216655263 ◽

2016 ◽

Vol 22 (1) ◽

pp. 127-133 ◽

Cited By ~ 11

Author(s):

Ali Fattahi ◽

Fatemeh Niyazi ◽

Behzad Shahbazi ◽

Mohammad Hosein Farzaei ◽

Gholamreza Bahrami

Keyword(s):

Diabetes Mellitus ◽

Cell Line ◽

Mechanism Of Action ◽

Glucose Absorption ◽

Rosa Canina ◽

Glucose Diffusion ◽

Treatment Of Diabetes ◽

Hepatocellular Carcinoma Cell Line ◽

Natural Agent

Rosa canina fruits have been used traditionally for the treatment of diabetes mellitus and its complications. The aim of current study was to evaluate the in vitro mechanism of action of R canina in managing diabetes mellitus. Cell proliferation and cytotoxicity assay were performed on pancreatic β-cells, βTC6. The protective activity of the extract on streptozotocin-induced death in βTC6 cells was studied. The effect of R canina on the metabolism of glucose in HepG2, a hepatocellular carcinoma cell line, was evaluated. The effect of the extract on glucose diffusion across the dialysis membrane, which is a comfortable model for assessing cellular glucose absorption, was evaluated. The results obtained from current study confirmed that R canina extract can act as a growth factor for pancreatic β-cell line providing a novel mechanism for the observed antidiabetic effect of this natural agent. Further preclinical studies are necessary to evaluate the perfect mechanism of action of R canina in diabetes mellitus.

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Effects of weak bases on the degradation of endogenous and exogenous proteins by rat yolk sacs

Biochemical Journal ◽

10.1042/bj1880895 ◽

1980 ◽

Vol 188 (3) ◽

pp. 895-903 ◽

Cited By ~ 29

Author(s):

G Livesey ◽

K E Williams ◽

S E Knowles ◽

F J Ballard

Keyword(s):

Bovine Serum Albumin ◽

Serum Albumin ◽

Bovine Serum ◽

Normal Values ◽

Free Medium ◽

Weak Base ◽

Weak Bases ◽

Endogenous Proteins ◽

Hydrolysis Of

In rat yolk sacs incubated in vitro, the rates of degradation of endogenous [3H]leucine-labelled proteins and of pinocytically ingested 125I-labelled bovine serum albumin were both decreased in the presence of either ammonium, methylammonium or ethylammonium ions (0-20 mM) or much lower concentrations of chloroquine (0-500 microM). These effects were also accompanied by an inhibition of pinocytosis, as measured by the rate of uptake of 125I-labelled polyvinylpyrrolidone, and by a fall in the [ATP]/[ADP] ratio within the tissue. Re-incubation in inhibitor-free medium of yolk sacs previously exposed to a weak base restored pinocytic and proteolytic capacities, except for tissues exposed to chloroquine at concentrations above 0.1 mM (these appeared to be cytotoxic); an attendent rise in [ATP]/[ADP] ratios to near normal values was also observed. Weak bases, at concentrations that fully arrested the breakdown of 125I-labelled albumin, failed to inhibit by more than 45% the degradation of [3H]leucine-labelled endogenous proteins. Since 125I-labelled bovine serum albumin has been shown to be degraded entirely intralysosomally by yolk sacs, this suggests either that the hydrolysis of endogenous proteins is shared between lysosomes and some other site or that, unlike 125I-labelled albumin, some endogenous proteins can be degraded within lysosomes at abnormally high pH.

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Comparison of the Low Temperature Degradation Properties of Two Y-TZP Ceramics for Dental Applications

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.492.107 ◽

2011 ◽

Vol 492 ◽

pp. 107-111 ◽

Cited By ~ 1

Author(s):

Yuan Fu Yi ◽

Ning Wen ◽

Xiao Ling Wang ◽

Long Quan Shao ◽

Chen Wang

Keyword(s):

Low Temperature ◽

Flexural Strength ◽

Monoclinic Phase ◽

Surface Microstructure ◽

Force Microscopy ◽

Dental Application ◽

Before And After ◽

Dental Applications ◽

Degradation Properties

The purpose of this study was to investigate the influence of in vitro low-temperature degradation (LTD) treatments on the structural stability and mechanical properties of two commercial Y-TZP ceramics candidate for dental application. TZ-3YS and TZ-3YS-E powder were chosen because of there minor differences of chemical composition. The two powders were compacted at 200MPa using cold isostatic pressure, and densely sintered at 1500°C and 1450°C for 2hr respectively. Two methods of in vitro LTD treatments were performed, the first is to autoclave specimens in steam at 134°C, 2bar, for 1 to 5hr; the second is to immerse specimens into 4% acetic acid at 80°C for 168 hr. XRD was used to identify the crystal phases, flexural strength were tested according to ISO 6872 standard, surface microstructure was evaluated by Atomic Force Microscopy (AFM). Results show that the relative content of monoclinic phase was increasing with the prolonged aging time, the TZ-3YS was more sensitive to LTD compared with TZ-3YS-E. LTD tests did not necessary reduce the flexural strength of Y-TZP ceramics, the nucleation and growth of monoclinic phase were detected by AFM, and the surface microstructure induced by LTD was not identical between the two Y-TZP ceramics. AFM was a sensitive method to evaluate the transformation of Y-TZP ceramics. To choose appropriate Y-TZP powder for dental application, it is mandatory to examine the microstructure before and after LTD.

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