Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 8.062
Filter
1.
Integr Cancer Ther ; 23: 15347354241253846, 2024.
Article in English | MEDLINE | ID: mdl-38721848

ABSTRACT

Vikil 20 is an herbal formula produced in Ghana and is widely marketed as a product to boost immunity as well as for general well-being. However, the pharmacological effect of this herbal preparation has not been proven scientifically. Therefore, this study was aimed at investigating the antioxidative as well as the anti-prostate cancer effects of the product. To assess the antioxidative effect of Vikil 20, the DPPH and ABTS activities were investigated. The total phenolic content was investigated using the Folin-Ciocalteu method. The cytotoxic effect of Vikil 20 against prostate cancer (PC-3) cells as well as normal (RAW 264.7) cells was investigated using the MTT assay whereas its anti-metastatic effect was analyzed using the cell migration assay. The effect of Vikil 20 on cell adhesion was analyzed via the cell adhesion assay whereas its effect on TNF-α secretion was investigated using a TNF-α detection kit. Vikil 20 demonstrated significant antioxidant effects by suppressing 57.61% and 92.88% respectively of DPPH and ABTS radicals at 1000 µg/mL with total phenolic contents of 140.45 mg GAE/g. Vikil 20 suppressed the proliferation of PC-3 cells by reducing the number of viable cells to 49.5% while sparing the RAW, 264.7 cells. Further, Vikil 20 significantly suppressed both cellular migration and adhesion of prostate cancer cells. Finally, suppression of cellular migration and adhesion is associated with a reduction in TNF-α secretion by PC-3 cells. Taken together, Vikil 20 was found to possess significant antioxidant and anti-prostate cancer effects in vitro.


Subject(s)
Antioxidants , Cell Movement , Cell Proliferation , Plant Extracts , Prostatic Neoplasms , Male , Humans , Prostatic Neoplasms/drug therapy , Prostatic Neoplasms/pathology , Cell Proliferation/drug effects , PC-3 Cells , Antioxidants/pharmacology , Cell Movement/drug effects , Mice , Animals , RAW 264.7 Cells , Free Radicals/metabolism , Plant Extracts/pharmacology , Cell Adhesion/drug effects , Cell Line, Tumor , Tumor Necrosis Factor-alpha/metabolism , Phenols/pharmacology
2.
J Chem Inf Model ; 64(10): 4168-4179, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38745447

ABSTRACT

Hydroxyprolines are abundant in nature and widely utilized by many living organisms. Isomerization of trans-4-hydroxy-d-proline (t4D-HP) to generate 2-amino-4-ketopentanoate has been found to need a glycyl radical enzyme HplG, which catalyzes the cleavage of the C-N bond, while dehydration of trans-4-hydroxy-l-proline involves a homologous enzyme of HplG. Herein, molecular dynamics simulations and quantum mechanics/molecular mechanics (QM/MM) calculations are employed to understand the reaction mechanism of HplG. Two possible reaction pathways of HplG have been explored to decipher the origin of its chemoselectivity. The QM/MM calculations reveal that the isomerization proceeds via an initial hydrogen shift from the Cγ site of t4D-HP to a catalytic cysteine radical, followed by cleavage of the Cδ-N bond in t4D-HP to form a radical intermediate that captures a hydrogen atom from the cysteine. Activation of the Cδ-H bond in t4D-HP to bring about dehydration of t4D-HP possesses an extremely high energy barrier, thus rendering the dehydration pathway implausible in HplG. On the basis of the current calculations, conserved residue Glu429 plays a pivotal role in the isomerization pathway: the hydrogen bonding between it and t4D-HP weakens the hydroxyalkyl Cγ-Hγ bond, and it acts as a proton acceptor to trigger the cleavage of the C-N bond in t4D-HP. Our current QM/MM calculations rationalize the origin of the experimentally observed chemoselectivity of HplG and propose an H-bond-assisted bond activation strategy in radical-containing enzymes. These findings have general implications on radical-mediated enzymatic catalysis and expand our understanding of how nature wisely and selectively activates the C-H bond to modulate catalytic selectivity.


Subject(s)
Cysteine , Glutamic Acid , Molecular Dynamics Simulation , Quantum Theory , Cysteine/chemistry , Cysteine/metabolism , Glutamic Acid/chemistry , Glutamic Acid/metabolism , Free Radicals/chemistry , Free Radicals/metabolism , Hydrogen Bonding
3.
Toxicol In Vitro ; 98: 105844, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38740103

ABSTRACT

Streptomycin (STR) is an aminoglycoside antibiotic with a broad-spectrum of activity and ototoxic potential. The mechanism of STR-induced inner ear damage has not been fully elucidated. It was previously found that STR binds to melanin, which may result in the accumulation of the drug in melanin-containing tissues. Melanin pigment is present in various parts of the inner ear, including the cochlea and vestibular organ. The present study aimed to assess if streptomycin generates oxidative stress and affects melanogenesis in normal human melanocytes. Moreover the variation of free radical concentration in STR-treated melanocytes was examined by electron paramagnetic resonance spectroscopy (EPR). We found that STR decreases cell metabolic activity and reduces melanin content. The observed changes in the activity of antioxidant enzymes activity in HEMn-DPs treated with streptomycin may suggest that the drug affects redox homeostasis in melanocytes. In this work EPR study expanded knowledge about free radicals in interactions of STR and melanin in melanocytes. The results may help elucidate the mechanisms of STR toxicity on pigment cells, including melanin-producing cells in the inner ear. This is important because understanding the mechanism of STR-induced ototoxicity would be helpful in developing new therapeutic strategies to protect patients' hearing.


Subject(s)
Anti-Bacterial Agents , Melanins , Melanocytes , Oxidative Stress , Streptomycin , Melanins/metabolism , Humans , Electron Spin Resonance Spectroscopy , Oxidative Stress/drug effects , Melanocytes/drug effects , Melanocytes/metabolism , Streptomycin/toxicity , Anti-Bacterial Agents/toxicity , Cells, Cultured , Cell Survival/drug effects , Free Radicals/metabolism , Cell Line
5.
Nature ; 629(8010): 98-104, 2024 May.
Article in English | MEDLINE | ID: mdl-38693411

ABSTRACT

Photobiocatalysis-where light is used to expand the reactivity of an enzyme-has recently emerged as a powerful strategy to develop chemistries that are new to nature. These systems have shown potential in asymmetric radical reactions that have long eluded small-molecule catalysts1. So far, unnatural photobiocatalytic reactions are limited to overall reductive and redox-neutral processes2-9. Here we report photobiocatalytic asymmetric sp3-sp3 oxidative cross-coupling between organoboron reagents and amino acids. This reaction requires the cooperative use of engineered pyridoxal biocatalysts, photoredox catalysts and an oxidizing agent. We repurpose a family of pyridoxal-5'-phosphate-dependent enzymes, threonine aldolases10-12, for the α-C-H functionalization of glycine and α-branched amino acid substrates by a radical mechanism, giving rise to a range of α-tri- and tetrasubstituted non-canonical amino acids 13-15 possessing up to two contiguous stereocentres. Directed evolution of pyridoxal radical enzymes allowed primary and secondary radical precursors, including benzyl, allyl and alkylboron reagents, to be coupled in an enantio- and diastereocontrolled fashion. Cooperative photoredox-pyridoxal biocatalysis provides a platform for sp3-sp3 oxidative coupling16, permitting the stereoselective, intermolecular free-radical transformations that are unknown to chemistry or biology.


Subject(s)
Amino Acids , Biocatalysis , Oxidative Coupling , Photochemical Processes , Amino Acids/biosynthesis , Amino Acids/chemistry , Amino Acids/metabolism , Biocatalysis/radiation effects , Directed Molecular Evolution , Free Radicals/chemistry , Free Radicals/metabolism , Glycine/chemistry , Glycine/metabolism , Glycine Hydroxymethyltransferase/metabolism , Glycine Hydroxymethyltransferase/chemistry , Indicators and Reagents , Light , Oxidative Coupling/radiation effects , Pyridoxal Phosphate/metabolism , Stereoisomerism , Amino Acids, Branched-Chain/chemistry , Amino Acids, Branched-Chain/metabolism
6.
J Drugs Dermatol ; 23(4): SF378083s5-SF378083s10, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38564405

ABSTRACT

Skin aging is influenced by various exogenous and endogenous factors, ranging from ultraviolet (UV) light exposure and environmental toxins to biological sources, such as those that arise from normal metabolic processes (eg, free radicals). Glycation is the normal process by which glucose and other reducing sugars react with proteins to form an array of heterogeneous biomolecular structures known as advanced glycation end-products (AGEs) over time. However, AGEs are toxic to human cells and are implicated in the acceleration of inflammatory and oxidative processes, with their accumulation in the skin being associated with increased skin dulling and yellowing, fine lines, wrinkles, and skin laxity. Clinicians should become cognizant of how AGEs develop, what their biological consequences are, and familiarize themselves with available strategies to mitigate their formation. J Drugs Dermatol.  2024;23:4(Suppl 1):s5-10.


Subject(s)
Glycation End Products, Advanced , Maillard Reaction , Humans , Glycation End Products, Advanced/metabolism , Glycation End Products, Advanced/toxicity , Sugars/adverse effects , Sugars/metabolism , Skin/metabolism , Free Radicals/metabolism
7.
Int J Mol Sci ; 25(8)2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38674159

ABSTRACT

Sepsis continues to overwhelm hospital systems with its high mortality rate and prevalence. A strategy to reduce the strain of sepsis on hospital systems is to develop a diagnostic/prognostic measure that identifies patients who are more susceptible to septic death. Current biomarkers fail to achieve this outcome, as they only have moderate diagnostic power and limited prognostic capabilities. Sepsis disrupts a multitude of pathways in many different organ systems, making the identification of a single powerful biomarker difficult to achieve. However, a common feature of many of these perturbed pathways is the increased generation of reactive oxygen species (ROS), which can alter gene expression, changes in which may precede the clinical manifestation of severe sepsis. Therefore, the aim of this study was to evaluate whether ROS-related circulating molecular signature can be used as a tool to predict sepsis survival. Here we created a ROS-related gene signature and used two Gene Expression Omnibus datasets from whole blood samples of septic patients to generate a 37-gene molecular signature that can predict survival of sepsis patients. Our results indicate that peripheral blood gene expression data can be used to predict the survival of sepsis patients by assessing the gene expression pattern of free radical-associated -related genes in patients, warranting further exploration.


Subject(s)
Reactive Oxygen Species , Sepsis , Humans , Sepsis/genetics , Sepsis/mortality , Sepsis/blood , Prognosis , Reactive Oxygen Species/metabolism , Biomarkers , Transcriptome , Gene Expression Profiling , Free Radicals/metabolism , Male , Female , Middle Aged
8.
Acc Chem Res ; 57(9): 1446-1457, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38603772

ABSTRACT

ConspectusEnzymes are desired catalysts for chemical synthesis, because they can be engineered to provide unparalleled levels of efficiency and selectivity. Yet, despite the astonishing array of reactions catalyzed by natural enzymes, many reactivity patterns found in small molecule catalysts have no counterpart in the living world. With a detailed understanding of the mechanisms utilized by small molecule catalysts, we can identify existing enzymes with the potential to catalyze reactions that are currently unknown in nature. Over the past eight years, our group has demonstrated that flavin-dependent "ene"-reductases (EREDs) can catalyze various radical-mediated reactions with unparalleled levels of selectivity, solving long-standing challenges in asymmetric synthesis.This Account presents our development of EREDs as general catalysts for asymmetric radical reactions. While we have developed multiple mechanisms for generating radicals within protein active sites, this account will focus on examples where flavin mononucleotide hydroquinone (FMNhq) serves as an electron transfer radical initiator. While our initial mechanistic hypotheses were rooted in electron-transfer-based radical initiation mechanisms commonly used by synthetic organic chemists, we ultimately uncovered emergent mechanisms of radical initiation that are unique to the protein active site. We will begin by covering intramolecular reactions and discussing how the protein activates the substrate for reduction by altering the redox-potential of alkyl halides and templating the charge transfer complex between the substrate and flavin-cofactor. Protein engineering has been used to modify the fundamental photophysics of these reactions, highlighting the opportunity to tune these systems further by using directed evolution. This section highlights the range of coupling partners and radical termination mechanisms available to intramolecular reactions.The next section will focus on intermolecular reactions and the role of enzyme-templated ternary charge transfer complexes among the cofactor, alkyl halide, and coupling partner in gating electron transfer to ensure that it only occurs when both substrates are bound within the protein active site. We will highlight the synthetic applications available to this activation mode, including olefin hydroalkylation, carbohydroxylation, arene functionalization, and nitronate alkylation. This section also discusses how the protein can favor mechanistic steps that are elusive in solution for the asymmetric reductive coupling of alkyl halides and nitroalkanes. We are aware of several recent EREDs-catalyzed photoenzymatic transformations from other groups. We will discuss results from these papers in the context of understanding the nuances of radical initiation with various substrates.These biocatalytic asymmetric radical reactions often complement the state-of-the-art small-molecule-catalyzed reactions, making EREDs a valuable addition to a chemist's synthetic toolbox. Moreover, the underlying principles studied with these systems are potentially operative with other cofactor-dependent proteins, opening the door to different types of enzyme-catalyzed radical reactions. We anticipate that this Account will serve as a guide and inspire broad interest in repurposing existing enzymes to access new transformations.


Subject(s)
Oxidoreductases , Oxidoreductases/metabolism , Oxidoreductases/chemistry , Free Radicals/chemistry , Free Radicals/metabolism , Biocatalysis , Flavins/chemistry , Flavins/metabolism , Hydroquinones/chemistry , Hydroquinones/metabolism , Flavin Mononucleotide/chemistry , Flavin Mononucleotide/metabolism , Electron Transport
9.
Int J Mol Sci ; 25(6)2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38542335

ABSTRACT

Reactive oxygen species (ROS) and free radicals work to maintain homeostasis in the body, but their excessive production causes damage to the organism. The human body is composed of a variety of cells totaling over 60 trillion cells. Each cell performs different functions and has a unique lifespan. The lifespan of cells is preprogrammed in their genes, and the death of cells that have reached the end of their lifespan is called apoptosis. This is contrary to necrosis, which is the premature death of cells brought about by physical or scientific forces. Each species has its own unique lifespan, which in humans is estimated to be up to 120 years. Elucidating the mechanism of the death of a single cell will lead to a better understanding of human death, and, conversely, the death of a single cell will lead to exploring the mechanisms of life. In this sense, research on active oxygen and free radicals, which are implicated in biological disorders and homeostasis, requires an understanding of both the physicochemical as well as the biochemical aspects. Based on the discussion above, it is clear to see that active oxygen and free radicals have dual functions of both injuring and facilitating homeostasis in living organisms.


Subject(s)
Antioxidants , Oxidative Stress , Humans , Reactive Oxygen Species/metabolism , Oxidative Stress/physiology , Free Radicals/metabolism , Antioxidants/metabolism , Apoptosis
10.
Molecules ; 29(6)2024 Mar 11.
Article in English | MEDLINE | ID: mdl-38542875

ABSTRACT

BACKGROUND: Trapa bispinosa shells (TBs) and its flesh (TBf) have been recognized for their medicinal properties, including antioxidant, antitumor, and immunomodulatory effects. Despite these benefits, TBs are often discarded as waste material, and their applications remain to be further explored. METHODS: In this study, we optimized the solid-state fermentation process of Ganoderma sinense (GS) with TBs using a response surface experiment methodology to obtain the fermented production with the highest water extract rate and DPPH free radical scavenging activity. We prepared and characterized pre-fermentation purified polysaccharides (P1) and post-fermentation purified polysaccharides (P2). Alcoholic extracts before (AE1) and after (AE2) fermentation were analyzed for active components such as polyphenols and flavonoids using UPLC-QTOF-MS/MS (ultra-performance liquid chromatography-quadrupole time-of-flight tandem mass spectrometry). Mouse macrophages (RAW 264.7) were employed to compare the immune-stimulating ability of polysaccharides and the antioxidant activity of AE1 and AE2. RESULTS: Optimal fermentation conditions comprised a duration of 2 days, a temperature of 14 °C, and a humidity of 77%. The peak water extract yield and DPPH free radical scavenging rate of the water extract from TBs fermented by GS were observed under these conditions. The enhanced activity may be attributed to changes in the polysaccharide structure and the components of the alcoholic extract. The P2 treatment group indicated more secretion of RAW 264.7 cells of NO, iNOS, IL-2, IL-10, and TNF-α than P1, which shows that the polysaccharides demonstrated increased immune-stimulating ability, with their effect linked to the NF-кB pathway. Moreover, the results of the AE2 treatment group indicated that secretion of RAW 264.7 cells of T-AOC and T-SOD increased and MDA decreased, which shows that the alcoholic extract demonstrated enhanced antioxidant activity, with its effect linked to the Nrf2/Keap1-ARE pathway. CONCLUSIONS: Biphasic fermentation of Trapa bispinosa shells by Ganoderma sinense could change the composition and structure of the polysaccharides and the composition of the alcoholic extract, which could increase the products' immunomodulatory and antioxidant activity.


Subject(s)
Antioxidants , Ganoderma , Lythraceae , Animals , Mice , Antioxidants/analysis , Fermentation , Kelch-Like ECH-Associated Protein 1/metabolism , Tandem Mass Spectrometry , NF-E2-Related Factor 2/metabolism , Polysaccharides/chemistry , Ganoderma/chemistry , Water/metabolism , Free Radicals/metabolism
11.
Yakugaku Zasshi ; 144(4): 419-429, 2024.
Article in Japanese | MEDLINE | ID: mdl-38556317

ABSTRACT

In view of the current claim by many researchers that biological aging is a treatable disease, the possibility is discussed whether the claim is realistic, based on several proposed mechanisms of aging. The definition of biological aging is stated referring to physiological aging and pathological aging, since biological aging must be defined for the discussion of whether it can be cured. Aging in animal model is compared with that in humans in terms of common age-associated phenotypes. Major proposed mechanisms of aging are next examined including Genome Instability Theory of aging, Free Radical or Oxidative Stress Theory of Aging, Mitochondrial Theory of Aging, Error Catastrophe Theory of Aging/Translational Error Theory of Aging, Altered Protein Theory of Aging/Proteostasis Theory of Aging, and Epigenetic Theory of Aging. Finally, we discuss whether treatment of aging as a disease is realistic in comparison with possible lifespan extension by retardation of biological aging.


Subject(s)
Aging , Oxidative Stress , Animals , Humans , Aging/metabolism , Oxidative Stress/physiology , Free Radicals/metabolism , Longevity/genetics , Mitochondria/metabolism
12.
Adv Healthc Mater ; 13(13): e2304125, 2024 May.
Article in English | MEDLINE | ID: mdl-38301194

ABSTRACT

Disturbance in the mitochondrial electron transport chain (ETC) is a key factor in the emerging discovery of immune cell activation in inflammatory diseases, yet specific regulation of ETC homeostasis is extremely challenging. In this paper, a mitochondrial complex biomimetic nanozyme (MCBN), which plays the role of an artificial "VI" complex and acts as an electron and free radical conversion factory to regulate ETC homeostasis is creatively developed. MCBN is composed of bovine serum albumin (BSA), polyethylene glycol (PEG), and triphenylphosphine (TPP) hierarchically encapsulating MnO2 polycrystalline particles. It has nanoscale size and biological properties like natural complexes. In vivo and in vitro experiments confirm that MCBN can target the mitochondrial complexes of inflammatory macrophages, absorb excess electrons in ETC, and convert the electrons to decompose H2O2. By reducing the ROS and ATP bursts and converting existing free radicals, inhibiting NLRP3 inflammatory vesicle activation and NF-κB signaling pathway, MCBN effectively suppresses macrophage M1 activation and inflammatory factor secretion. It also demonstrates good inflammation control and significantly alleviates alveolar bone loss in a mouse model of ligation-induced periodontitis. This is the first nanozyme that mimics the mitochondrial complex and regulates ETC, demonstrating the potential application of MCBN in immune diseases.


Subject(s)
Macrophages , Mitochondria , Animals , Mice , Macrophages/metabolism , Macrophages/drug effects , Macrophages/immunology , Mitochondria/metabolism , Mitochondria/drug effects , RAW 264.7 Cells , Inflammation/metabolism , Inflammation/pathology , Free Radicals/chemistry , Free Radicals/metabolism , Reactive Oxygen Species/metabolism , Serum Albumin, Bovine/chemistry , Polyethylene Glycols/chemistry , Manganese/chemistry , Electrons , Oxides/chemistry , Organophosphorus Compounds/chemistry , Organophosphorus Compounds/pharmacology , Mice, Inbred C57BL , Manganese Compounds/chemistry , Manganese Compounds/pharmacology
13.
Toxicol Sci ; 199(2): 246-260, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38310335

ABSTRACT

Particulate matter (PM) containing environmentally persistent free radicals (EPFR) is formed by the incomplete combustion of organic wastes, resulting in the chemisorption of pollutants to the surface of PM containing redox-active transition metals. In prior studies in mice, EPFR inhalation impaired endothelium-dependent vasodilation. These findings were associated with aryl hydrocarbon receptor (AhR) activation in the alveolar type-II (AT-II) cells that form the air-blood interface in the lung. We thus hypothesized that AhR activation in AT-II cells promotes the systemic release of mediators that promote endothelium dysfunction peripheral to the lung. To test our hypothesis, we knocked down AhR in AT-II cells of male and female mice and exposed them to 280 µg/m3 EPFR lo (2.7e + 16 radicals/g) or EPFR (5.5e + 17 radicals/g) compared with filtered air for 4 h/day for 1 day or 5 days. AT-II-AhR activation-induced EPFR-mediated endothelial dysfunction, reducing endothelium-dependent vasorelaxation by 59%, and eNOS expression by 50%. It also increased endothelin-1 mRNA levels in the lungs and peptide levels in the plasma in a paracrine fashion, along with soluble vascular cell adhesion molecule-1 and iNOS mRNA expression, possibly via NF-kB activation. Finally, AhR-dependent increases in antioxidant response signaling, coupled to increased levels of 3-nitrotyrosine in the lungs of EPFR-exposed littermate control but not AT-II AhR KO mice suggested that ATII-specific AhR activation promotes oxidative and nitrative stress. Thus, AhR activation at the air-blood interface mediates endothelial dysfunction observed peripheral to the lung, potentially via release of systemic mediators.


Subject(s)
Mice, Inbred C57BL , Particulate Matter , Receptors, Aryl Hydrocarbon , Animals , Receptors, Aryl Hydrocarbon/metabolism , Receptors, Aryl Hydrocarbon/genetics , Male , Particulate Matter/toxicity , Female , Free Radicals/metabolism , Air Pollutants/toxicity , Mice , Endothelium, Vascular/drug effects , Endothelium, Vascular/metabolism , Endothelium, Vascular/physiopathology , Oxidative Stress/drug effects , Inhalation Exposure , Lung/drug effects , Lung/metabolism , Lung/blood supply , Endothelin-1/metabolism , Vasodilation/drug effects , Nitric Oxide Synthase Type III/metabolism , Basic Helix-Loop-Helix Transcription Factors
15.
ACS Nano ; 18(4): 2982-2991, 2024 Jan 30.
Article in English | MEDLINE | ID: mdl-38235677

ABSTRACT

Cells are damaged during hypoxia (blood supply deprivation) and reoxygenation (oxygen return). This damage occurs in conditions such as cardiovascular diseases, cancer, and organ transplantation, potentially harming the tissue and organs. The role of free radicals in cellular metabolic reprogramming under hypoxia is under debate, but their measurement is challenging due to their short lifespan and limited diffusion range. In this study, we employed a quantum sensing technique to measure the real-time production of free radicals at the subcellular level. We utilize fluorescent nanodiamonds (FNDs) that exhibit changes in their optical properties based on the surrounding magnetic noise. This way, we were able to detect the presence of free radicals. To specifically monitor radical generation near mitochondria, we coated the FNDs with an antibody targeting voltage-dependent anion channel 2 (anti-VDAC2), which is located in the outer membrane of mitochondria. We observed a significant increase in the radical load on the mitochondrial membrane when cells were exposed to hypoxia. Subsequently, during reoxygenation, the levels of radicals gradually decreased back to the normoxia state. Overall, by applying a quantum sensing technique, the connections among hypoxia, free radicals, and the cellular redox status has been revealed.


Subject(s)
Hypoxia , Myocytes, Cardiac , Humans , Myocytes, Cardiac/metabolism , Free Radicals/metabolism , Hypoxia/metabolism , Mitochondria/metabolism , Oxygen/metabolism
16.
Reprod Sci ; 31(6): 1486-1495, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38212583

ABSTRACT

PURPOSE: Polycystic ovary syndrome (PCOS) is an endocrine disorder that primarily affects women of reproductive age. It is recognized as the leading cause of infertility due to anovulation. This research aims to evaluate the diagnostic potential of oxidative stress biomarkers, including advanced oxidation protein products (AOPP), malondialdehyde (MDA), uric acid (UA), and nitric oxide (NO), in identifying PCOS. METHODS: A literature search was conducted in the EMBASE, PubMed, Cochrane Library, and Scopus databases. The standardized mean difference (SMD) and 95% confidence interval (CI) were employed to assess the correlation between free radical product and PCOS. Moreover, the presence of heterogeneity among the studies was assessed utilizing the I2 statistic and Cochran Q test. The methodological rigor of the incorporated studies was assessed through the application of the Newcastle-Ottawa Scale. Furthermore, the presence of publication bias was determined via Begg and Egger tests. RESULTS: This meta-analysis reviewed 38 observational studies, including 17,845 women. The results revealed a significant association between PCOS in women and alterations in free radical levels. The study revealed that the PCOS group had significantly higher levels of AOPP (SMD = 3.193; 95% CI, 2.86 to 3.25), UA (SMD = 0.68; 95% CI, 0.24 to 1.13), and MDA (SMD = 1.16; 95% CI, 0.77 to 1.56) compared to the healthy control group. Furthermore, the analysis found a significantly lower level of NO (SMD = (- 0.59); 95% CI, - 1.15 to - 0.03) in the PCOS patient. CONCLUSION: Screening of specific biomarkers associated with free radical products could provide valuable benefits in the prognosis and diagnosis of PCOS.


Subject(s)
Biomarkers , Oxidative Stress , Polycystic Ovary Syndrome , Polycystic Ovary Syndrome/diagnosis , Polycystic Ovary Syndrome/blood , Humans , Female , Biomarkers/blood , Free Radicals/metabolism , Uric Acid/blood , Nitric Oxide/metabolism , Advanced Oxidation Protein Products/blood , Malondialdehyde/blood
17.
Yakugaku Zasshi ; 144(4): 431-439, 2024 Apr 01.
Article in Japanese | MEDLINE | ID: mdl-38246655

ABSTRACT

The neural cell death in cerebral infarction is suggested to be ferroptosis-like cell death, involving the participation of 15-lipoxygenase (15-LOx). Ferroptosis is induced by lipid radical species generated through the one-electron reduction of lipid hydroperoxides, and it has been shown to propagate intracellularly and intercellularly. At lower oxygen concentration, it appeared that both regiospecificity and stereospecificity of conjugated diene moiety in lipoxygenase-catalysed lipid hydroperoxidation are drastically lost. As a result, in the reaction with linoleic acid, the linoleate 9-peroxyl radical-ferrous lipoxygenase complex dissolves into the linoleate 9-peroxyl radical and ferrous 15-lipoxygenase. Subsequently, the ferrous 15-lipoxygenase then undergoes one-electron reduction of 13-hydroperoxy octadecadienoic acid, generating an alkoxyl radical (pseudoperoxidase reaction). A part of the produced lipid alkoxyl radicals undergoes cleavage of C-C bonds, liberating small molecular hydrocarbon radicals. Particularly, in ω-3 polyunsaturated fatty acids, which are abundant in the vascular and nervous systems, the liberation of small molecular hydrocarbon radicals was more pronounced compared to ω-6 polyunsaturated fatty acids. The involvement of these small molecular hydrocarbon radicals in the propagation of membrane lipid damage is suggested.


Subject(s)
Arachidonate 15-Lipoxygenase , Linoleic Acid , Peroxides , Linoleic Acid/metabolism , Fatty Acids, Unsaturated/chemistry , Fatty Acids, Unsaturated/metabolism , Lipid Peroxides/metabolism , Lipoxygenase/metabolism , Hydrocarbons , Cell Death , Oxygen/metabolism , Free Radicals/metabolism
18.
Mol Neurobiol ; 61(1): 188-199, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37596436

ABSTRACT

Retinopathy fails to halt even after diabetic patients in poor glycemic control try to institute tight glycemic control, suggesting a "metabolic memory" phenomenon, and the experimental models have demonstrated that mitochondria continue to be damaged/dysfunctional, fueling into the vicious cycle of free radicals. Our aim was to investigate the role of removal of the damaged mitochondria in the metabolic memory. Using human retinal endothelial cells (HRECs), incubated in 20 mM D-glucose for 4 days, followed by 5 mM D-glucose for 4 additional days, mitochondrial turnover, formation of mitophagosome, and mitophagy flux were evaluated. Mitophagy was confirmed in a rat model of metabolic memory where the rats were kept in poor glycemic control (blood glucose ~ 400 mg/dl) for 3 months soon after induction of streptozotocin-induced diabetes, followed by 3 additional months of good control (BG < 150 mg/dl). Reversal of high glucose by normal glucose had no effect on mitochondrial turnover and mitophagosome formation, and mitophagy flux remained compromised. Similarly, 3 months of good glycemic control in rats, which had followed 3 months of poor glycemic control, had no effect on mitophagy flux. Thus, poor turnover/removal of the damaged mitochondria, initiated during poor glycemic control, does not benefit from the termination of hyperglycemic insult, and the damaged mitochondria continue to produce free radicals, suggesting the importance of mitophagy in the metabolic memory phenomenon associated with the continued progression of diabetic retinopathy.


Subject(s)
Diabetes Mellitus, Experimental , Diabetic Retinopathy , Hyperglycemia , Humans , Rats , Animals , Diabetic Retinopathy/metabolism , Endothelial Cells/metabolism , Rats, Wistar , Mitochondria/metabolism , Hyperglycemia/complications , Hyperglycemia/metabolism , Glucose/metabolism , Diabetes Mellitus, Experimental/metabolism , Free Radicals/metabolism , Free Radicals/pharmacology
19.
Biochim Biophys Acta Gen Subj ; 1868(2): 130527, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38043915

ABSTRACT

Acetaldehyde can be found in human cells as a byproduct of various metabolic pathways, including oxidative processes such as lipid peroxidation. This secondary product of lipid peroxidation plays a role in various pathological processes, leading to various types of civilization diseases. In this study, the formation of free acetaldehyde induced by oxygen-centred radicals was studied in monocyte-like cell line U937. Exposure of U937 cells to peroxyl/alkoxyl radicals induced by azocompound resulted in the formation of free acetaldehyde. Acetaldehyde is formed by the cleavage of fatty acids, which represents the breakdown of fatty acids into smaller fragments initiated by the cyclization of lipid peroxyl radical and ß-scission of lipid alkoxyl radical. The cleavage of fatty acids alters the integrity of the plasma and nuclear membrane, leading to the loss of cell viability. Understanding the pathological processes of acetaldehyde formation is an active area of research with potential implications for preventing and treating various diseases associated with oxidative stress.


Subject(s)
Acetaldehyde , Monocytes , Humans , Lipid Peroxidation , Free Radicals/metabolism , U937 Cells , Monocytes/metabolism , Fatty Acids/metabolism , Reactive Oxygen Species
20.
Vet Res Commun ; 48(1): 317-327, 2024 Feb.
Article in English | MEDLINE | ID: mdl-37684400

ABSTRACT

Aflatoxins, particularly AFB1, are the most common feed contaminants worldwide, causing significant economic losses to the livestock sector. The current paper describes an outbreak of aflatoxicosis in a herd of 160 male young goat kids (3-4 months), of which 68 young kids succumbed over a period of 25 days after showing neurological signs of abnormal gait, progressive paralysis and head pressing. The haematobiochemical investigation showed reduced haemoglobin, leucocyte count, PCV level, increased levels of AST, ALT, glucose, BUN, creatinine and reduced level of total protein. Grossly, kids had pale mucous membranes, pale and swollen liver; right apical lobe consolidation, and petechiation of the synovial membrane of the hock joints. The microscopic changes were characterized by multifocal hemorrhages, status spongiosus/ vacuolation, vasculitis, focal to diffuse gliosis, satellitosis, and ischemic apoptotic neurons in different parts of the brain and spinal cord. These changes corresponded well with strong immunoreactivity for AFB1 in neurons, glia cells (oligodendrocytes, astrocytes, and ependymal cells) in various anatomical sites of the brain. The higher values of LPO and reduced levels of antioxidant enzymes (Catalase, SOD, GSH) with strong immunoreactivity of 8-OHdG in the brain indicating high level of oxidative stress. Further, the higher immunosignaling of caspase-3 and caspase-9 in the brain points towards the association with intrinsic pathway of apoptosis. The toxicological analysis of feed samples detected high amounts of AFB1 (0.38ppm). These findings suggest that AFB1 in younger goat kids has more of neurotoxic effect mediated through caspase dependent intrinsic pathway.


Subject(s)
Brain Diseases , Goat Diseases , Male , Animals , Goats/metabolism , Aflatoxin B1/toxicity , Aflatoxin B1/metabolism , Apoptosis , Oxidative Stress , Liver/metabolism , Free Radicals/metabolism , Free Radicals/pharmacology , Brain Diseases/metabolism , Brain Diseases/veterinary , Goat Diseases/chemically induced
SELECTION OF CITATIONS
SEARCH DETAIL
...