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Biochemical and Biophysical Research... Jan 2017Disruption of redox homeostasis is a key phenotype of many pathological conditions. Though multiple oxidizing compounds such as hydrogen peroxide are widely recognized... (Review)
Review
Disruption of redox homeostasis is a key phenotype of many pathological conditions. Though multiple oxidizing compounds such as hydrogen peroxide are widely recognized as mediators and inducers of oxidative stress, increasingly, attention is focused on the role of lipid hydroperoxides as critical mediators of death and disease. As the main component of cellular membranes, lipids have an indispensible role in maintaining the structural integrity of cells. Excessive oxidation of lipids alters the physical properties of cellular membranes and can cause covalent modification of proteins and nucleic acids. This review discusses the synthesis, toxicity, degradation, and detection of lipid peroxides in biological systems. Additionally, the role of lipid peroxidation is highlighted in cell death and disease, and strategies to control the accumulation of lipid peroxides are discussed.
Topics: Alzheimer Disease; Animals; Cell Death; Humans; Lipid Peroxidation; Lipid Peroxides; Lipoxygenase Inhibitors; Metabolic Networks and Pathways; Oxidation-Reduction; Reducing Agents
PubMed: 28212725
DOI: 10.1016/j.bbrc.2016.10.086 -
Molecules (Basel, Switzerland) Jun 2020Enzymatic browning because of polyphenol oxidases (PPOs) contributes to the color quality of fruit and vegetable (FV) products. Physical and chemical methods have been... (Review)
Review
Enzymatic browning because of polyphenol oxidases (PPOs) contributes to the color quality of fruit and vegetable (FV) products. Physical and chemical methods have been developed to inhibit the activity of PPOs, and several synthetic chemical compounds are commonly being used as PPO inhibitors in FV products. Recently, there has been an emphasis on consumer-oriented innovations in the food industry. Consumers tend to urge the use of natural and environment-friendly PPO inhibitors. The purpose of this review is to summarize the mechanisms underlying the anti-browning action of chemical PPO inhibitors and current trends in the research on these inhibitors. Based on their mechanisms of action, chemical inhibitors can be categorized as antioxidants, reducing agents, chelating agents, acidulants, and/or mixed-type PPO inhibitors. Here, we focused on the food ingredients, dietary components, food by-products, and waste associated with anti-browning activity.
Topics: Antioxidants; Catechol Oxidase; Chelating Agents; Food Handling; Fruit; Maillard Reaction; Oxidation-Reduction; Reducing Agents
PubMed: 32549214
DOI: 10.3390/molecules25122754 -
Journal of Oleo Science 2022Since many of the current chemicals used to remove iron rust are hazardous to the environment and human health, the combined use of a reducing agent and a biodegradable...
Since many of the current chemicals used to remove iron rust are hazardous to the environment and human health, the combined use of a reducing agent and a biodegradable chelating agent has been suggested as an environmental friendly and highly safe alternative. In the present work, the compatibility of the newly devised cleaning test with a model iron rust stain was confirmed by X-ray diffraction and scanning electron microscopy. Additionally, the cleaning efficiency of the method was evaluated by X-ray fluorescence. The cleaning mechanism and the synergistic effect of the reducing agent and the chelating agent was investigated using the phenanthroline absorption measurement method, and the results revealed that the reduced iron ions were dissolved by the chelating agent. The cleaning test proved that tetrasodium 3-hydroxy-2,2'-iminodisuccinate (HIDS) is a promising biodegradable chelating agent as an alternative to ethylenediaminetetraacetic acid (EDTA) for removing iron rust. It was also confirmed that the type of reducing agent used determines the pH at which detergency is enhanced. The detergency of the combination of the reducing agent and the biodegradable chelating agent was equal to or higher than the detergency of the acid agent, and thus, it was concluded that the proposed method has a great potential for commercial use.
Topics: Chelating Agents; Humans; Iron; Reducing Agents
PubMed: 35370212
DOI: 10.5650/jos.ess21297 -
Molecules (Basel, Switzerland) May 2023It has been experimentally reported that not only oxidation reactions but also reduction reactions occur in aqueous solutions under ultrasound without any additives.... (Review)
Review
It has been experimentally reported that not only oxidation reactions but also reduction reactions occur in aqueous solutions under ultrasound without any additives. According to the numerical simulations of chemical reactions inside an air or argon bubble in water without any additives under ultrasound, reducing agents produced from the bubbles are H, H2, HO2 (which becomes superoxide anion (O2-) in liquid water), NO, and HNO2 (which becomes NO2- in liquid water). In addition, H2O2 sometimes works as a reducing agent. As the reduction potentials of H and H2 (in strongly alkaline solutions for H2) are higher than those of RCHOH radicals, which are usually used to reduce metal ions, H and H2 generated from cavitation bubbles are expected to reduce metal ions to produce metal nanoparticles (in strongly alkaline solutions for H2 to work). It is possible that the superoxide anion (O2-) also plays some role in the sonochemical reduction of some solutes. In strongly alkaline solutions, hydrated electrons (e-aq) formed from H atoms in liquid water may play an important role in the sonochemical reduction of solutes because the reduction potential is extremely high. The influence of ultrasonic frequency on the amount of H atoms produced from a cavitation bubble is also discussed.
PubMed: 37241940
DOI: 10.3390/molecules28104198 -
Frontiers in Endocrinology 2022Deoxycholic Acid (DCA), which is an FDA-approved compound for the reduction of submental fat, has evolved through an unanticipated and surprising sequence of events.... (Review)
Review
Deoxycholic Acid (DCA), which is an FDA-approved compound for the reduction of submental fat, has evolved through an unanticipated and surprising sequence of events. Initially, it was used as a solvent for Phosphatidylcholine (PDC), which was thought to promote lipolysis, but it was later proven to be the bioactive component of the formula and is currently widely used as Kybella. It has also been used off-label to treat other types of fat deposits like lipomas, HIV lipodystrophy, and excess orbital fat. Despite widespread clinical use, there has been no consensus clarifying the mechanisms of DCA and PDC alone or in combination. Furthermore, despite PDC's removal from the FDA-approved formula, some studies do suggest it plays an important role in fat reduction. To provide some clarity, we conducted a PubMed search and reviewed 41 articles using a comprehensive list of terms in three main categories, using the AND operator: 1) Phosphatidylcholines 2) Deoxycholic Acid, and 3) Lipoma. We isolated articles that studied PDC, DCA, and a PDC/DCA compound using cell biology, molecular and genetic techniques. We divided relevant articles into those that studied these components using histologic techniques and those that utilized specific cell death and lipolysis measurement techniques. Most morphologic studies indicated that PDC/DCA, DCA, and PDC, all induce some type of cell death with accompanying inflammation and fibrosis. Most morphologic studies also suggest that PDC/DCA and DCA alone are non-selective for adipocytes. Biochemical studies describing PDC and DCA alone indicate that DCA acts as a detergent and rapidly induces necrosis while PDC induces TNF-α release, apoptosis, and subsequent enzymatic lipolysis after at least 24 hours. Additional papers have suggested a synergistic effect between the two compounds. Our review integrates the findings of this growing body of literature into a proposed mechanism of fat reduction and provides direction for further studies.
Topics: Adipocytes; Adipose Tissue; Deoxycholic Acid; Humans; Inflammation; Reducing Agents
PubMed: 35399925
DOI: 10.3389/fendo.2022.841889 -
Nano Convergence Jan 2022The seed-mediated method is a general procedure for the synthesis of gold nanorods (Au NRs), and reducing agents such as ascorbic acid (AA) and hydroquinone (HQ) are...
The seed-mediated method is a general procedure for the synthesis of gold nanorods (Au NRs), and reducing agents such as ascorbic acid (AA) and hydroquinone (HQ) are widely used for the growth process. Further, they are mild reducing agents; however, when AA is used, controlling the size of Au NRs with a higher aspect ratio (localized surface plasmon resonance (LSPR) peak, λ > 900 nm) is challenging because it results in a faster growth rate of Au NRs. In contrast, when HQ is used, Au NRs with a higher aspect ratio can be synthesized as it slows down the growth rate of the Au NRs and greatly enhanced the λ. However, the increase in λ is still needs not satisfactory due to the limited enhancement in the aspect ratio of Au NRs due to utilization of single reducing agent. The growth kinetics of the Au NRs can be modulated by controlling the reducing power of the reducing agents. In such scenario, judicious use of two reducing agents such as AA and HQ simultaneously can help us to design Au NRs of higher aspect ratio in a controlled manner due to the optimum growth rate resulting from the combined effect of both the reducing agents. In this study, we investigated the effect of the two reducing agents by controlling the volume ratios. When the growth solution contains both the reducing agents, the growth of Au NRs is first initiated by the fast reduction of Au to Au due to stronger reducing power of the AA and when the AA in the growth solution is completely utilized, further growth of the Au NRs continues as a result of the HQ thereby resulting to high aspect ratio Au NRs. Consequently, the LSPR peak (λ > 1275 nm) can be tuned by controlling the volume ratios of the reducing agents.
PubMed: 35038061
DOI: 10.1186/s40580-021-00296-1 -
Channels (Austin, Tex.) Dec 2024The patch clamp method is a widely applied electrophysiological technique used to understand ion channel activity and cellular excitation. The formation of a high...
The patch clamp method is a widely applied electrophysiological technique used to understand ion channel activity and cellular excitation. The formation of a high resistance giga-ohm seal is required to obtain high-quality recordings but can be challenging due to variables including operator experience and cell preparation. Therefore, the identification of methods to promote the formation and longevity of giga-ohm seals may be beneficial. In this report, we describe our observation that the application of reducing agents (DTT and TCEP) to the external bath solution during whole-cell patch clamp recordings of heterologous cells (HEK and LM) and cultured primary cells (DRG neurons) enhanced the success of giga-ohm seal formation. Reducing agents also maintained the integrity of the seal for longer periods of time at strong hyperpolarizing voltages, whereas an oxidizing agent (HO) appeared to have the opposite effect. In summary, we report a useful tool to improve the quality of patch clamp recordings that may be helpful in certain experimental contexts.
Topics: Reducing Agents; Hydrogen Peroxide; Cells, Cultured
PubMed: 38154061
DOI: 10.1080/19336950.2023.2297621 -
The Journal of Organic Chemistry Aug 2022We report the synthesis, chemical properties, and disulfide bond-reducing performance of a dithiol called NACMEAA, conceived as a hybrid of two biologically relevant...
We report the synthesis, chemical properties, and disulfide bond-reducing performance of a dithiol called NACMEAA, conceived as a hybrid of two biologically relevant thiols: cysteine and cysteamine. NACMEAA is conveniently prepared from inexpensive l-cystine in an efficient manner. As a nonvolatile, highly soluble, and neutral compound at physiological pH with the first thiol p value of 8.0, NACMEAA is reactive and user-friendly. We also demonstrate that NACMEAA reduces disulfide bonds in GSSG and lysozyme.
Topics: Cysteamine; Cysteine; Disulfides; Oxidation-Reduction; Reducing Agents; Sulfhydryl Compounds; Toluene
PubMed: 35862282
DOI: 10.1021/acs.joc.2c01050 -
Molecules (Basel, Switzerland) Oct 2022Nanotechnology is constantly expanding, with nanomaterials being more and more used in common commercial products that define our modern life. Among all types of... (Review)
Review
Nanotechnology is constantly expanding, with nanomaterials being more and more used in common commercial products that define our modern life. Among all types of nanomaterials, nanoparticles (NPs) occupy an important place, considering the great amount that is produced nowadays and the diversity of their applications. Conventional techniques applied to synthesize NPs have some issues that impede them from being appreciated as safe for the environment and health. The alternative to these might be the use of living organisms or biological extracts that can be involved in the green approach synthesis of NPs, a process that is free of harmful chemicals, cost-effective and a low energy consumer. Several factors, including biological reducing agent concentration, initial precursor salt concentration, agitation, reaction time, pH, temperature and light, can influence the characteristics of biologically synthesized NPs. The interdependence between these reaction parameters was not explored, being the main impediment in the implementation of the biological method on an industrial scale. Our aim is to present a brief review that focuses on the current knowledge regarding how the aforementioned factors can control the size and shape of green-synthesized NPs. We also provide an overview of the biomolecules that were found to be suitable for NP synthesis. This work is meant to be a support for researchers who intend to develop new green approaches for the synthesis of NPs.
Topics: Green Chemistry Technology; Metal Nanoparticles; Nanoparticles; Nanotechnology; Plant Extracts; Reducing Agents
PubMed: 36235008
DOI: 10.3390/molecules27196472 -
Biochemistry Sep 2020Protein biochemistry protocols typically include disulfide bond reducing agents to guard against unwanted thiol oxidation and protein aggregation. Commonly used...
Protein biochemistry protocols typically include disulfide bond reducing agents to guard against unwanted thiol oxidation and protein aggregation. Commonly used disulfide bond reducing agents include dithiothreitol, β-mercaptoethanol, glutathione, and the tris(alkyl)phosphine compounds tris(2-carboxyethyl)phosphine (TCEP) and tris(3-hydroxypropyl)phosphine (THPP). While studying the catalytic activity of the NAD(P)H-dependent enzyme Δ-pyrroline-5-carboxylate reductase, we unexpectedly observed a rapid non-enzymatic chemical reaction between NAD and the reducing agents TCEP and THPP. The product of the reaction exhibits a maximum ultraviolet absorbance peak at 334 nm and forms with an apparent association rate constant of 231-491 M s. The reaction is reversible, and nuclear magnetic resonance characterization (H, C, and P) of the product revealed a covalent adduct between the phosphorus of the tris(alkyl)phosphine reducing agent and the C4 atom of the nicotinamide ring of NAD. We also report a 1.45 Å resolution crystal structure of short-chain dehydrogenase/reductase with the NADP-TCEP reaction product bound in the cofactor binding site, which shows that the adduct can potentially inhibit enzymes. These findings serve to caution researchers when using TCEP or THPP in experimental protocols with NAD(P). Because NAD(P)-dependent oxidoreductases are widespread in nature, our results may be broadly relevant.
Topics: Bacterial Proteins; Burkholderia; Disulfides; Dithiothreitol; NAD; Oxidation-Reduction; Phosphines; Protein Conformation; Protein Domains; Reducing Agents; Short Chain Dehydrogenase-Reductases
PubMed: 32841567
DOI: 10.1021/acs.biochem.0c00490