scholarly journals Single-Atom Fe-Anchored Nano-Diamond With Enhanced Dual-Enzyme Mimicking Performance for H2O2 and Glutathione Detection

2022 ◽  
Vol 9 ◽  
Author(s):  
Ying Liu ◽  
Jianghong Yan ◽  
Yu Huang ◽  
Zhiheng Sun ◽  
Huijing Zhang ◽  
...  
Keyword(s):  
Detection Limit ◽  
Color Change ◽  
Colorimetric Method ◽  
Free Radical Scavenger ◽  
The Body ◽  
Single Atom ◽  
Iron Oxide Nanoparticle ◽  
Radical Scavenger ◽  
Colorimetric Sensing ◽  
One Pot

Glutathione (GSH) is an important antioxidant and free radical scavenger that converts harmful toxins into harmless substances and excretes them out of the body. In the present study, we successfully prepared single-atom iron oxide-nanoparticle (Fe-NP)-modified nanodiamonds (NDs) named Fe-NDs via a one-pot in situ reduction method. This nanozyme functionally mimics two major enzymes, namely, peroxidase and oxidase. Accordingly, a colorimetric sensing platform was designed to detect hydrogen peroxide (H2O2) and GSH. Owing to their peroxidase-like activity, Fe-NDs can oxidize colorless 3,3′,5,5′-tetramethylbenzidine (TMB) into blue with sufficient linearity at H2O2 concentrations of 1–60 μM and with a detection limit of 0.3 μM. Furthermore, using different concentrations of GSH, oxidized TMB can be reduced to TMB, and the color change from blue to nearly colorless can be observed by the naked eye (linear range, 1–25 μM; detection limit, 0.072 μM). The established colorimetric method based on oxidase-like activity can be successfully used to detect reduced GSH in tablets and injections with good selectivity and high sensitivity. The results of this study exhibited reliable consistency with the detection results obtained using high-performance liquid chromatography (HPLC). Therefore, the Fe-NDs colorimetric sensor designed in this study offers adequate accuracy and sensitivity.

scholarly journals Melatonin in Prevention of the Sequence from Reflux Esophagitis to Barrett’s Esophagus and Esophageal Adenocarcinoma: Experimental and Clinical Perspectives

2018 ◽  
Vol 19 (7) ◽  
pp. 2033 ◽  
Author(s):  
Jolanta Majka ◽  
Mateusz Wierdak ◽  
Iwona Brzozowska ◽  
Marcin Magierowski ◽  
Aleksandra Szlachcic ◽  
...  
Keyword(s):  
Barrett’S Esophagus ◽  
Reflux Esophagitis ◽  
Barrett's Esophagus ◽  
Free Radical Scavenger ◽  
The Body ◽  
Oxidative Enzymes ◽  
Esophageal Injury ◽  
Radical Scavenger ◽  
Target Cells ◽  
Liver Uptake

Melatonin is a tryptophan-derived molecule with pleiotropic activities which is produced in all living organisms. This “sleep” hormone is a free radical scavenger, which activates several anti-oxidative enzymes and mechanisms. Melatonin, a highly lipophilic hormone, can reach body target cells rapidly, acting as the circadian signal to alter numerous physiological functions in the body. This indoleamine can protect the organs against a variety of damaging agents via multiple signaling. This review focused on the role played by melatonin in the mechanism of esophagoprotection, starting with its short-term protection against acute reflux esophagitis and then investigating the long-term prevention of chronic inflammation that leads to gastroesophageal reflux disease (GERD) and Barrett’s esophagus. Since both of these condition are also identified as major risk factors for esophageal carcinoma, we provide some experimental and clinical evidence that supplementation therapy with melatonin could be useful in esophageal injury by protecting various animal models and patients with GERD from erosions, Barrett’s esophagus and neoplasia. The physiological aspects of the synthesis and release of this indoleamine in the gut, including its release into portal circulation and liver uptake is examined. The beneficial influence of melatonin in preventing esophageal injury from acid-pepsin and acid-pepsin-bile exposure in animals as well as the usefulness of melatonin and its precursor, L-tryptophan in prophylactic and supplementary therapy against esophageal disorders in humans, are also discussed.

scholarly journals Melatonin’s neuroprotective role in mitochondria and its potential as a biomarker in aging, cognition and psychiatric disorders

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lindsay M. Melhuish Beaupre ◽  
Gregory M. Brown ◽  
Vanessa F. Gonçalves ◽  
James L. Kennedy
Keyword(s):  
Psychiatric Disorders ◽  
Free Radical Scavenger ◽  
The Body ◽  
Radical Scavenger ◽  
Pineal Melatonin ◽  
Mediated Effects ◽  
Ability To Act ◽  
High Concentrations ◽  
Mitochondrial Oxidative Metabolism

AbstractMelatonin is an ancient molecule that is evident in high concentrations in various tissues throughout the body. It can be separated into two pools; one of which is synthesized by the pineal and can be found in blood, and the second by various tissues and is present in these tissues. Pineal melatonin levels display a circadian rhythm while tissue melatonin does not. For decades now, melatonin has been implicated in promoting and maintaining sleep. More recently, evidence indicates that it also plays an important role in neuroprotection. The beginning of our review will summarize this literature. As an amphiphilic, pleiotropic indoleamine, melatonin has both direct actions and receptor-mediated effects. For example, melatonin has established effects as an antioxidant and free radical scavenger both in vitro and in animal models. This is also evident in melatonin’s prominent role in mitochondria, which is reviewed in the next section. Melatonin is synthesized in, taken up by, and concentrated in mitochondria, the powerhouse of the cell. Mitochondria are also the major source of reactive oxygen species as a byproduct of mitochondrial oxidative metabolism. The final section of our review summarizes melatonin’s potential role in aging and psychiatric disorders. Pineal and tissue melatonin levels both decline with age. Pineal melatonin declines in individuals suffering from psychiatric disorders. Melatonin’s ability to act as a neuroprotectant opens new avenues of exploration for the molecule as it may be a potential treatment for cases with neurodegenerative disease.

Effect of Methylprednisolone and Reduced Glutathione on Survival in Mice and Hepatic Energy Metabolism in Rats with Endotoxin Shock

1985 ◽  
Vol 1 (3) ◽  
pp. 249-251
Author(s):  
I. Kosugi ◽  
K. Tajimi ◽  
K. Okada
Keyword(s):  
Energy Metabolism ◽  
Sodium Succinate ◽  
Endotoxin Shock ◽  
Free Radical Scavenger ◽  
The Body ◽  
Radical Scavenger ◽  
Beneficial Effects ◽  
Methylprednisolone Sodium Succinate ◽  
Hepatic Energy Metabolism

Reduced glytathione (GSH) is the tripeptide of glycine, cysteine and glutamic acid and is widely distributed in the body. FSH has been reported to comprise at least 90% of the nonprotein sulfhydryl (NPSH). Although the role of GSH in the tissue has not been clearly established, it is known to be a cofactor for enzymes, a substrate in detoxifications, and a free radical scavenger.Several investigators have reported that the level of NPSH, mainly GSH, in the tissue was decreased in several types of shock and that exogenous administration of GSH has beneficial effects on shock (1,2). This study was designed to evaluate the effects of GSH on the survival rate in mice and the hepatic energy metabolism in rats after administration of endotoxin. These results were compared with those of methylprednisolone sodium succinate (MP), since many investigators have reported that the large doses of glucocorticoid have beneficial effects in several types of shock in experimental animals and in man (3,4).

One-pot synthesis of gold nanoparticles by using 4-aminoantipyrine as a novel reducing and capping agent for simultaneous colorimetric sensing of four triptan-family drugs

2014 ◽  
Vol 6 (15) ◽  
pp. 5972-5980 ◽  
Author(s):  
Karuna A. Rawat ◽  
Kiran R. Surati ◽  
Suresh Kumar Kailasa
Keyword(s):  
Gold Nanoparticles ◽  
Color Change ◽  
Capping Agent ◽  
Colorimetric Sensing ◽  
One Pot ◽  
Au Nps ◽  
One Pot Synthesis

We prepared Au NPs using 4-aminoantipyrine as a novel reagent and the Au NPs aggregation was induced by triptan-family drugs independently, resulting a color change from pink to blue.

scholarly journals Phenosafranin-Based Colorimetric-Sensing Platform for Nitrite Detection Enabled by Griess Assay

Sensors ◽  
2020 ◽  
Vol 20 (5) ◽  
pp. 1501
Author(s):  
Jingzhou Hou ◽  
Huixiang Wu ◽  
Xin Shen ◽  
Chao Zhang ◽  
Changjun Hou ◽  
...  
Keyword(s):  
Detection Limit ◽  
Color Change ◽  
Quantitative Detection ◽  
Optimal Detection ◽  
Colorimetric Sensing ◽  
Promising Candidate ◽  
Sensing Platform ◽  
Acidic Conditions ◽  
Hcl Concentration ◽  
Griess Assay

A facile and effective colorimetric-sensing platform based on the diazotization of phenosafranin for the detection of NO 2 − under acidic conditions using the Griess assay is presented. Diazotization of commercial phenosafranin produces a color change from purplish to blue, which enables colorimetric quantitative detection of NO 2 − . Optimal detection conditions were obtained at a phenosafranin concentration of 0.25 mM, HCl concentration of 0.4 M, and reaction time of 20 min. Under the optimized detection conditions, an excellent linearity range from 0 to 20 μM was obtained with a detection limit of 0.22 μM. Favorable reproducibility and selectivity of the colorimetric sensing platform toward NO 2 − were also verified. In addition, testing spiked ham sausage, bacon, and sprouts samples demonstrated its excellent practicability. The presented colorimetric sensing platform is a promising candidate for the detection of NO 2 − in real applications.

scholarly journals Effect of Melatonin for Regulating Mesenchymal Stromal Cells and Derived Extracellular Vesicles

2021 ◽  
Vol 9 ◽  
Author(s):  
Zi-Yi Feng ◽  
Shu-De Yang ◽  
Ting Wang ◽  
Shu Guo
Keyword(s):  
Regenerative Medicine ◽  
Extracellular Vesicles ◽  
Mesenchymal Stromal Cells ◽  
Stromal Cells ◽  
Free Radical Scavenger ◽  
The Body ◽  
Research Interest ◽  
Radical Scavenger ◽  
Paracrine Signaling ◽  
Anti Inflammatory

Melatonin is a hormone, synthesized in the pineal gland, which primarily controls the circadian rhythm of the body. In recent years, melatonin has also been shown to regulate metabolism, provide neuroprotection, and act as an anti-inflammatory, free radical scavenger. There has also been a recent research interest in the role of melatonin in regulating mesenchymal stromal cells (MSCs). MSCs are pivotal for their ability to differentiate into a variety of different tissues. There is also increasing evidence for the therapeutic prospects of MSCs via paracrine signaling. In addition to secreting cytokines and chemokines, MSCs can secrete extracellular vesicles (EVs), allowing them to respond to injury and promote tissue regeneration. While there has been a major research interest in the use of MSCs for regenerative medicine, the clinical application is limited by many risks, including tumorigenicity, senescence, and sensitivity to toxic environments. The use of MSC-derived EVs for cell-free therapy can potentially avoid the disadvantages of MSCs, which makes this an exciting prospect for regenerative medicine. Prior research has shown that MSCs, via paracrine mechanisms, can identify receptor-independent responses to melatonin and then activate a series of downstream pathways, which exert a variety of effects, including anti-tumor and anti-inflammatory effects. Here we review the synthesis of melatonin, its mechanisms of action, and the effect of melatonin on MSCs via paracrine signaling. Furthermore, we summarize the current clinical applications of melatonin and discuss future prospects.

scholarly journals Chemiluminescent carbon nanodots as sensors for hydrogen peroxide and glucose

Nanophotonics ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 3597-3604 ◽  
Author(s):  
Cheng-Long Shen ◽  
Guang-Song Zheng ◽  
Meng-Yuan Wu ◽  
Jian-Yong Wei ◽  
Qing Lou ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Detection Limit ◽  
The Body ◽  
Carbon Nanodots ◽  
One Pot ◽  
New Class ◽  
Metabolism Disorder ◽  
Disease Diagnostics ◽  
Glucose Metabolism Disorder

AbstractHydrogen peroxide (H2O2) is an important product generated in the body and related to many pathophysiological processes and glucose metabolism disorder can cause many fatal diseases in living bodies. Therefore, the sensing of H2O2 and glucose is of great significance in disease diagnostics and treatment. Fluorescent carbon dots (CDs) are one new class of nanoprobes for H2O2 and glucose. Nevertheless, the CD-based sensor is always based on its fluorescence response, which is influenced by the auto-fluorescent interference. Herein, efficient fluorescent CDs were synthesized by one-pot solvothermal method, and the CDs exhibit bright and persistent deep-red (DR) chemiluminescence (CL) in bis(2,4,6-trichlorophenyl) oxalate and H2O2 solution with a CL quantum yield of (8.22 ± 0.30) × 10−3, which is amongst the highest values in ever reported nanomaterials for chemical analysis. Employing the CDs as CL nanoprobes, sensitive sensing for H2O2 has been achieved with a detection limit of 11.7 μM, and further for glucose detection with a detection limit of 12.6 μM. The DR CL CDs is promising to be applied in blood glucose analysis or in vivo biosensor.

scholarly journals Carbon Dots Fluorescence-Based Colorimetric Sensor for Sensitive Detection of Aluminum Ions with a Smartphone

Chemosensors ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 25
Author(s):  
Wei Wei ◽  
Juan Huang ◽  
Wenli Gao ◽  
Xiangyang Lu ◽  
Xingbo Shi
Keyword(s):  
Detection Limit ◽  
Carbon Dots ◽  
Color Change ◽  
Fluorescence Emission ◽  
Blue Emission ◽  
One Pot ◽  
Sensitive Analysis ◽  
Aluminum Ions ◽  
Operation Process ◽  
Uv Lamp

In this work, blue emission carbon dots (CDs) are synthesized in the one-pot solvothermal method using naringin as precursor. The CDs are used to develop a ratiometric fluorescence sensor for the sensitive analysis of Al3+ with a detection limit of 113.8 nM. A fluorescence emission peak at 500 nm gradually appears, whereas the original fluorescence peak at 420 nm gradually decreases upon the increase in the Al3+ concentration. More importantly, the obvious color change of the CDs probe from blue to green under a 360 nm UV lamp can be identified by a smartphone and combined with the RGB (red/green/blue) analysis. This results in a visual and sensitive analysis of Al3+ with a detection limit of 5.55 μM. Moreover, the high recovery is in the 92.46–104.10% range, which demonstrates the high accuracy of this method for actual samples’ analysis. The use of a smartphone and the RGB analysis greatly simplifies the operation process, saves equipment cost, shortens the detection time, and provides a novel method for the instant, on-site, visual detection of Al3+ in actual samples.

Melatonin reduces high levels of lipid peroxidation induced by potassium iodate in porcine thyroid

2019 ◽  
pp. 1-7 ◽  
Author(s):  
Paulina Iwan ◽  
Jan Stepniak ◽  
Malgorzata Karbownik-Lewinska
Keyword(s):  
Lipid Peroxidation ◽  
Oxidative Damage ◽  
Membrane Lipids ◽  
Chemical Properties ◽  
Iodine Concentration ◽  
Free Radical Scavenger ◽  
Radical Scavenger ◽  
Protective Effects ◽  
Potassium Iodate ◽  
Hormone Synthesis

Abstract. Iodine is essential for thyroid hormone synthesis. Under normal iodine supply, calculated physiological iodine concentration in the thyroid is approx. 9 mM. Either potassium iodide (KI) or potassium iodate (KIO3) are used in iodine prophylaxis. KI is confirmed as absolutely safe. KIO3 possesses chemical properties suggesting its potential toxicity. Melatonin (N-acetyl-5-methoxytryptamine) is an effective antioxidant and free radical scavenger. Study aims: to evaluate potential protective effects of melatonin against oxidative damage to membrane lipids (lipid peroxidation, LPO) induced by KI or KIO3 in porcine thyroid. Homogenates of twenty four (24) thyroids were incubated in presence of either KI or KIO3 without/with melatonin (5 mM). As melatonin was not effective against KI-induced LPO, in the next step only KIO3 was used. Homogenates were incubated in presence of KIO3 (200; 100; 50; 25; 20; 15; 10; 7.5; 5.0; 2.5; 1.25 mM) without/with melatonin or 17ß-estradiol. Five experiments were performed with different concentrations of melatonin (5.0; 2.5; 1.25; 1.0; 0.625 mM) and one with 17ß-estradiol (1.0 mM). Malondialdehyde + 4-hydroxyalkenals (MDA + 4-HDA) concentration (LPO index) was measured spectrophotometrically. KIO3 increased LPO with the strongest damaging effect (MDA + 4-HDA level: ≈1.28 nmol/mg protein, p < 0.05) revealed at concentrations of around 15 mM, thus corresponding to physiological iodine concentrations in the thyroid. Melatonin reduced LPO (MDA + 4-HDA levels: from ≈0.97 to ≈0,76 and from ≈0,64 to ≈0,49 nmol/mg protein, p < 0.05) induced by KIO3 at concentrations of 10 mM or 7.5 mM. Conclusion: Melatonin can reduce very strong oxidative damage to membrane lipids caused by KIO3 used in doses resulting in physiological iodine concentrations in the thyroid.

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