scholarly journals Antioxidant action of SMe1EC2, the low-basicity derivative of the pyridoindole stobadine, in cell free chemical models and at cellular level

2014 ◽  
Vol 7 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Aneta Balcerczyk ◽  
Grzegorz Bartosz ◽  
Joanna Drzewinska ◽  
Łukasz Piotrowski ◽  
Łukasz Pulaski ◽  
...  
Keyword(s):  
Antiradical Activity ◽  
Radical Scavenging ◽  
Parent Drug ◽  
Cellular Level ◽  
Model Systems ◽  
Antioxidant Action ◽  
Structural Analogue ◽  
Chemical Models ◽  
High Basicity ◽  
Free Model

Abstract The aim of the study was to evaluate the antioxidant action of SMe1EC2, the structural analogue of the hexahydropyridoindole antioxidant stobadine. The antiradical activity of SMe1EC2 was found to be higher when compared to stobadine, as determined both in cell-free model systems of AAPH-induced oxidation of dihydrorhodamine 123 and 2´,7´-dichloro-dihydrofluorescein diacetate, and in the cellular system of stimulated macrophages RAW264.7. Analysis of proliferation of HUVEC and HUVEC-ST cells revealed absence of cytotoxic effect of SMe1EC2 at concentrations below 100 μM. The antioxidant activity of SMe1EC2, superior to the parent drug stobadine, is accounted for by both the higher intrinsic free radical scavenging action and by the better bioavailability of the low-basicity SMe1EC2 relative to the high-basicity stobadine.

Note: A Comparative Study on the in Vitro Antiradical Activity and Hydroxyl Free Radical Scavenging Activity in Aged Red Wines

2003 ◽  
Vol 9 (6) ◽  
pp. 383-387 ◽  
Author(s):  
P. Kefalas ◽  
S. Kallithraka ◽  
I. Parejo ◽  
D. P. Makris
Keyword(s):  
Free Radical ◽  
Antiradical Activity ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Free Radical Scavenging ◽  
Free Radical Scavenging Activity ◽  
Scavenging Activity ◽  
Red Wines ◽  
Hydroxyl Free Radical ◽  
Important Relationship

The antiradical and hydroxyl free radical scavenging activities were estimated in twenty-five, aged red wines from different areas in Greece. The antiradical activity (AAR) was determined by means of the wellknown DPPH• method, and its values ranged from 24.7 to 125.1. A novel, chemiluminescence-based, highly sensitive assay was applied for determination of the hydroxyl free radical scavenging activity (SAHFR), which varied from 1.62 to 12.22 mM quercetin equivalents. The values from the two assays correlated very well (r2 =0.8542, P<0.001), which confirmed an important relationship between SAHFR and AAR. This tendency in aged red wines, which may be significant in evaluating the antioxidant behaviour of red wine polyphenols, is discussed on the basis of previous research and relevant data.

Reaction kinetics during early hydration of calcined phyllosilicates in clinker-free model systems

2021 ◽  
Vol 143 ◽  
pp. 106382
Author(s):  
Sebastian Scherb ◽  
Matthias Maier ◽  
Nancy Beuntner ◽  
Karl-Christian Thienel ◽  
Jürgen Neubauer
Keyword(s):  
Reaction Kinetics ◽  
Model Systems ◽  
Early Hydration ◽  
Free Model

Activins, Inhibins, and Follistatins: From Endocrinology to Signaling. A Paradigm for the New Millennium

2002 ◽  
Vol 227 (9) ◽  
pp. 724-752 ◽  
Author(s):  
Corrine Welt ◽  
Yisrael Sidis ◽  
Henry Keutmann ◽  
Alan Schneyer
Keyword(s):  
Hormone Secretion ◽  
Signal Propagation ◽  
Cellular Level ◽  
Model Systems ◽  
Pituitary Hormone ◽  
New Paradigm ◽  
Activin Signaling ◽  
Physiological Relevance ◽  
Paracrine Growth Factor

It has been 70 years since the name inhibin was used to describe a gonadal factor that negatively regulated pituitary hormone secretion. The majority of this period was required to achieve purification and definitive characterization of inhibin, an event closely followed by identification and characterization of activin and follistatin (FS). In contrast, the last 15–20 years saw a virtual explosion of information regarding the biochemistry, physiology, and biosynthesis of these proteins, as well as identification of activin receptors, and a unique mechanism for FS action—the nearly irreversible binding and neutralization of activin. Many of these discoveries have been previously summarized; therefore, this review will cover the period from the mid 1990s to present, with particular emphasis on emerging themes and recent advances. As the field has matured, recent efforts have focused more on human studies, so the endocrinology of inhibin, activin, and FS in the human is summarized first. Another area receiving significant recent attention is local actions of activin and its regulation by both FS and inhibin. Because activin and FS are produced in many tissues, we chose to focus on a few particular examples with the most extensive experimental support, the pituitary and the developing follicle, although nonreproductive actions of activin and FS are also discussed. At the cellular level, it now seems that activin acts largely as an autocrine and/or paracrine growth factor, similar to other members of the transforming growh factor β superfamily. As we discuss in the next section, its actions are regulated extracellularly by both inhibin and FS. In the final section, intracellular mediators and modulators of activin signaling are reviewed in detail. Many of these are shared with other transforming growh factor β superfamily members as well as unrelated molecules, and in a number of cases, their physiological relevance to activin signal propagation remains to be elucidated. Nevertheless, taken together, recent findings suggest that it may be more appropriate to consider a new paradigm for inhibin, activin, and FS in which activin signaling is regulated extracellularly by both inhibin and FS whereas a number of intracellular proteins act to modulate cellular responses to these activin signals. It is therefore the balance between activin and all of its modulators, rather than the actions of any one component, that determines the final biological outcome. As technology and model systems become more sophisticated in the next few years, it should become possible to test this concept directly to more clearly define the role of activin, inhibin, and FS in reproductive physiology.

scholarly journals Cell Tracking for Organoids: Lessons From Developmental Biology

2021 ◽  
Vol 9 ◽  
Author(s):  
Max A. Betjes ◽  
Xuan Zheng ◽  
Rutger N. U. Kok ◽  
Jeroen S. van Zon ◽  
Sander J. Tans
Keyword(s):  
Cell Tracking ◽  
Cellular Level ◽  
Model Systems ◽  
Great Promise ◽  
Cellular Processes ◽  
The Past ◽  
Fluorescent Markers ◽  
Lineage Trees ◽  
Microscopy Techniques ◽  
Organizational Principles

Organoids have emerged as powerful model systems to study organ development and regeneration at the cellular level. Recently developed microscopy techniques that track individual cells through space and time hold great promise to elucidate the organizational principles of organs and organoids. Applied extensively in the past decade to embryo development and 2D cell cultures, cell tracking can reveal the cellular lineage trees, proliferation rates, and their spatial distributions, while fluorescent markers indicate differentiation events and other cellular processes. Here, we review a number of recent studies that exemplify the power of this approach, and illustrate its potential to organoid research. We will discuss promising future routes, and the key technical challenges that need to be overcome to apply cell tracking techniques to organoid biology.

scholarly journals Phytochemical analysis, Antimicrobial, insecticidal and antiradical activity of Hydnocarpus pentandra (Buch.-Ham.) Oken

2017 ◽  
Vol 9 (4) ◽  
pp. 576
Author(s):  
Prashith Kekuda TR ◽  
Dunkana Negussa Kenie ◽  
Chetan DM ◽  
Raghavendra L Hallur
Keyword(s):  
Leaf Extract ◽  
Antiradical Activity ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Extraction Process ◽  
In Vitro Assays ◽  
Phytochemical Analysis ◽  
Zone Of Inhibition ◽  
Bioactive Agents

<p><strong>Objectives</strong>: The present study was conducted to evaluate antimicrobial, insecticidal and radical scavenging activity of leaf extract of <em>Hydnocarpus pentandra</em> (Buch.-Ham.) Oken belonging to the family Achariaceae.</p><p><strong>Methods</strong>: Extraction process of shade dried and powdered leaf was carried out by maceration technique. Extract was screened for phytochemicals by standard tests. Antibacterial and antifungal activity of leaf extract was determined by Agar well diffusion and Poisoned food technique respectively. Antiradical activity of leaf extract was evaluated by two in vitro assays namely 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azinobis 3-ethylbenzothiazoline 6-sulfonate (ABTS) free radical scavenging assays. Insecticidal activity of leaf extract was determined against II instar and IV instar larvae of <em>Aedes aegypti</em>.</p><p><strong>Results</strong>: Preliminary phytochemical analysis showed the presence of alkaloids, flavonoids, tannins, saponins, glycosides, triterpenes and steroids in the leaf extract. Leaf extract exhibited marked inhibitory activity against Gram positive bacteria when compared to Gram negative bacteria. <em>Bacillus cereus</em> (zone of inhibition 1.86±0.05cm) and <em>Escherichia coli</em> (zone of inhibition 1.06±0.05cm) were inhibited to highest and least extent respectively. Extract was effective in inhibiting mycelial growth of seed-borne fungi. Among fungi, the susceptibility to extract was in the order: <em>Curvularia</em> sp. (53.64% inhibition) &gt; <em>Fusarium</em> sp. (45.81% inhibition) &gt; <em>Alternaria</em> sp. (35.08% inhibition). The extract exhibited concentration dependent larvicidal activity with marked activity being observed against II instar larvae (LC<sub>50</sub> value 0.79mg/ml) when compared to IV instar larvae (LC<sub>50</sub> value 1.37mg/ml). Leaf extract scavenged DPPH and ABTS radicals dose dependently with an IC<sub>50</sub> value of 13.91µg/ml and 6.03µg/ml respectively.</p><p><strong>Conclusions</strong>: The plant is shown to be an important source of bioactive agents. The observed bioactivities could be attributed to the phytochemicals present in the leaf extract. Further studies on characterization and bioactivity determination of isolated components from leaf extract are to be carried out.</p>

Assay-Guided Extraction and Kinetics of Radical Scavenging Activity of Curcumin from the Rhizome of Curcuma longa Linn

2019 ◽  
Vol 8 (1) ◽  
Author(s):  
Jubril Olayinka Akolade ◽  
Hussein O.B. Oloyede ◽  
Amuzat Olalekan Aliyu ◽  
Sarah Abimbola Akande ◽  
Aderoumu Ibrahim Ganiyu ◽  
...  
Keyword(s):  
Antiradical Activity ◽  
Radical Scavenging Activity ◽  
Curcuma Longa ◽  
Radical Scavenging ◽  
Weight Ratio ◽  
Pharmaceutical Products ◽  
Appreciable Amount ◽  
Absolute Methanol ◽  
Second Phase ◽  
Scavenging Activity

Extraction of phytoceuticals from medicinal plants need to be optimized to produce standardized, dose-dependent and reliable extracts to meet food or drug administration regulations for translation into approved nutraceutical or pharmaceutical products. Effect of selected limiting extraction variables on yield and antiradical activity of curcumin-rich extract from Curcuma longa rhizomes was investigated. Assay-guided response (free radical scavenging activity) was used to determine the optimized set of extraction parameters. Curcumin-rich extract was produced using solvent boiling process at 65 oC with absolute methanol of weight ratio 1:50 (w/v) within 1 h. Relative radical scavenging activity of the extract derived using the optimized set of parameters recorded an IC50 of 497 μg/ml and its total antiradical capacity determined within 6 h (76 - 85 % at a concentration of 400 – 600 μg/ml) was not significantly different from that of commercially available natural curcumin used as reference. Time-dependent kinetic analysis revealed an initial fast burst in rate of activity (2.27 – 7.77 min-1) followed by a slow reaction rate in a steady second phase (0.12 – 0.54 min-1). Conclusively, appreciable amount of curcumin-rich extract of enhanced antiradical activity was extracted from the rhizome of C. longa using assay-guided procedure.

scholarly journals DPPH-Scavenging Activities and Structure-Activity Relationships of Phenolic Compounds

2010 ◽  
Vol 5 (11) ◽  
pp. 1934578X1000501 ◽  
Author(s):  
Cheng-Dong Zheng ◽  
Gang Li ◽  
Hu-Qiang Li ◽  
Xiao-Jing Xu ◽  
Jin-Ming Gao ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Antiradical Activity ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Basic Structure ◽  
Hydroxyl Group ◽  
Structure Activity Relationships ◽  
Structure Activity ◽  
Dpph Scavenging ◽  
Dpph Radical Scavenging

Thirty-eight phenolic compounds (including 31 flavonoids) were examined for their DPPH radical-scavenging activities, and structure-activity relationships were evaluated. Specifically, the presence of an Ortho-dihydroxyl structure in phenolics is largely responsible for their excellent antiradical activity. 3-Hydroxyl was also essential to generate a high radical-scavenging activity. An increasing number of hydroxyls on flavones with a 3′,4′-dihydroxyl basic structure, the presence of a third hydroxyl group at C-5′, a phloroglucinol structure, glycosylation and methylation of the hydroxyls, and some other hydroxyls, for example 5-, and 7-hydroxyl in ring A, decreased the radical-scavenging activities of flavonoids and other phenolics.

scholarly journals ANTIMICROBIAL, ANTIRADICAL AND INSECTICIDAL ACTIVITY OF GARDENIA GUMMIFERA L. F. (RUBIACEAE)

2017 ◽  
Vol 9 (10) ◽  
pp. 265 ◽  
Author(s):  
Prashith Kekuda T. R. ◽  
Raghavendra H. L. ◽  
Shilpa M. ◽  
Pushpavathi D. ◽  
Tejaswini Petkar ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Insecticidal Activity ◽  
Leaf Extract ◽  
Antiradical Activity ◽  
Radical Scavenging ◽  
Fruit Extract ◽  
Fruit Extracts ◽  
Ic50 Value ◽  
Agar Well Diffusion Assay ◽  
Dose Dependent

Objective: The present study was carried out to investigate antimicrobial, antiradical and insecticidal potential of leaf and fruit of Gardenia gummifera L. f. (Rubiaceae).Methods: The leaf and fruits were shade dried, powdered and extracted by maceration process using methanol. Antibacterial activity was evaluated against Gram positive and Gram negative bacteria by Agar well diffusion assay. Antifungal activity was determined against six seed-borne fungi by Poisoned food technique. Antiradical activity of leaf and fruit extracts was evaluated by 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azinobis 3-ethylbenzothiazoline 6-sulfonate (ABTS) radical scavenging assays. Insecticidal activity of leaf and fruit extracts, in terms of larvicidal and pupicidal activity, was assessed against larvae and pupae of Aedes aegypti.Results: Both the extracts inhibited all test bacteria. Marked antibacterial activity was displayed by fruit extract when compared to leaf extract. S. epidermidis and E. coli were inhibited to highest and least extent by both extracts respectively. Fruit extract was found to exhibit higher antifungal effect when compared to leaf extract. Leaf extract and fruit extract exhibited highest inhibitory activity against A. niger and A. flavus respectively. Leaf and fruit extracts scavenged DPPH radical’s dose dependently with an IC50 value of 49.01µg/ml and 2.53µg/ml respectively. The scavenging of ABTS by leaf and fruit extracts was dose dependent and the IC50 value for leaf and fruit extract was 2.58µg/ml and 2.31µg/ml respectively. Fruit extract was shown to exhibit marked antiradical activity when compared to leaf extract. Leaf and fruit extracts exhibited dose dependent insecticidal activity in terms of larvicidal and pupicidal activity and the susceptibility of larvae and pupae to extracts was in the order II instar larvae>IV instar larvae>pupae. Fruit extract displayed marked insecticidal potential when compared to leaf extract.Conclusion: Overall, fruit extract of G. gummifera exhibited marked antimicrobial, antiradical and insecticidal activity when compared to leaf extract. The plant can be used for developing agents/formulations effective against infectious microorganisms, oxidative stress and insect vectors that transmit dreadful diseases. The observed bioactivities could be ascribed to the presence of active principles which are to be isolated and characterized.

scholarly journals Antioxidant Peptides from the Protein Hydrolysate of Spanish Mackerel (Scomberomorous niphonius) Muscle by in Vitro Gastrointestinal Digestion and Their in Vitro Activities

Marine Drugs ◽  
2019 ◽  
Vol 17 (9) ◽  
pp. 531 ◽  
Author(s):  
Zhao ◽  
Yang ◽  
Wang ◽  
Zhao ◽  
Chi ◽  
...  
Keyword(s):  
Protein Hydrolysate ◽  
Radical Scavenging ◽  
Model Systems ◽  
Dpph Radical ◽  
Antioxidant Peptides ◽  
Gastrointestinal Digestion ◽  
Spanish Mackerel ◽  
In Vitro Gastrointestinal Digestion ◽  
Dpph Radical Scavenging

For the full use of Spanish mackerel (Scomberomorous niphonius) muscle to produce antioxidant peptides, the proteins of Spanish mackerel muscle were separately hydrolyzed under five kinds of enzymes and in vitro gastrointestinal digestion, and antioxidant peptides were isolated from the protein hydrolysate using ultrafiltration and multiple chromatography methods. The results showed that the hydrolysate (SMPH) prepared using in vitro GI digestion showed the highest degree of hydrolysis (27.45 ± 1.76%) and DPPH radical scavenging activity (52.58 ± 2.68%) at the concentration of 10 mg protein/mL among the six protein hydrolysates, and 12 peptides (SMP-1 to SMP-12) were prepared from SMPH. Among them, SMP-3, SMP-7, SMP-10, and SMP-11 showed the higher DPPH radical scavenging activities and were identified as Pro-Glu-Leu-Asp-Trp (PELDW), Trp-Pro-Asp-His-Trp (WPDHW), and Phe-Gly-Tyr-Asp-Trp-Trp (FGYDWW), and Tyr-Leu-His-Phe-Trp (YLHFW), respectively. PELDW, WPDHW, FGYDWW, and YLHFW showed high scavenging activities on DPPH radical (EC50 1.53, 0.70, 0.53, and 0.97 mg/mL, respectively), hydroxyl radical (EC50 1.12, 0.38, 0.26, and 0.67 mg/mL, respectively), and superoxide anion radical (EC50 0.85, 0.49, 0.34, and 1.37 mg/mL, respectively). Moreover, PELDW, WPDHW, FGYDWW, and YLHFW could dose-dependently inhibit lipid peroxidation in the linoleic acid model system and protect plasmid DNA (pBR322DNA) against oxidative damage induced by H2O2 in the tested model systems. In addition, PELDW, WPDHW, FGYDWW, and YLHFW could retain their high activities when they were treated under a low temperature (<60 °C) and a moderate pH environment (pH 5–9). These present results indicate that the protein hydrolysate, fractions, and isolated peptides from Spanish mackerel muscle have strong antioxidant activity and might have the potential to be used in health food products.

Cardiac physiology at the cellular level: use of cultured HL-1 cardiomyocytes for studies of cardiac muscle cell structure and function

2004 ◽  
Vol 286 (3) ◽  
pp. H823-H829 ◽  
Author(s):  
Steven M. White ◽  
Phillip E. Constantin ◽  
William C. Claycomb
Keyword(s):  
Cell Line ◽  
Cell Structure ◽  
Ischemia Reperfusion ◽  
Cellular Level ◽  
Model Systems ◽  
Cardiac Physiology ◽  
Cardiac Phenotype ◽  
Pathological Conditions ◽  
And Function

HL-1 cells are currently the only cardiomyocyte cell line available that continuously divides and spontaneously contracts while maintaining a differentiated cardiac phenotype. Extensive characterization using microscopic, genetic, immunohistochemical, electrophysiological, and pharmacological techniques has demonstrated how similar HL-1 cells are to primary cardiomyocytes. In the few years that HL-1 cells have been available, they have been used in a variety of model systems designed to answer important questions regarding cardiac biology at the cellular and molecular levels. Whereas HL-1 cells have been used to study normal cardiomyocyte function with regard to signaling, electrical, metabolic, and transcriptional regulation, they have also been used to address pathological conditions such as hypoxia, hyperglycemia-hyperinsulinemia, apoptosis, and ischemia-reperfusion. The availability of an immortalized, contractile cardiac cell line has provided investigators with a tool for probing the intricacies of cardiomyocyte function. In this review, we describe the culture and characterization of HL-1 cardiomyocytes as well as various model systems that have been developed using these cells to gain a better understanding of cardiac biology at the cellular and molecular levels.

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