Lipid peroxidation is a free radical initiated chain oxidation of unsaturated lipids. With respect to the ubiquity of unsaturated fatty acids in the cellular membranes, the peroxidative damage has the potential to affect many cellular functions. Some of the products of lipid peroxidation are diffusible and can spread the damage far beyond the site of the original free radical attack. There is an interdependency between reactive oxygen species and lipid peroxidation - reactive oxygen species initiate the reactions of lipid peroxidation and are also produced in these reactions as intermediates. The generation of reactive oxygen species can be triggered either by nonenzymatic mechanisms, in which iron ions play the major role, or by a wide range of enzymatic systems. The primary damaging effect of lipid peroxidation is exerted by the interactions with proteins and DNA. These interactions are then revealed at the subcellular (cellular organelles), cellular, and organ levels. The production of lipid peroxides interferes with the regulation of several metabolic pathways. In this review, particular attention is focused on the interaction of non-specifically formed lipid peroxides with the regulatory factors produced by the controlled oxidation of arachidonic acid (prostaglandins and leukotrienes), the effects on ionic pumps and intracellular calcium metabolism, the participation of lipid peroxidation in the ageing process, and the modulation of hormonal regulations by lipid peroxidation. Lipid peroxidation is induced at the level of the whole organism by various extrinsic factors such as ionizing irradiation, physical activity, diet and fasting, and various drugs. There is increasing awareness of the association between pathologic states and lipid peroxidation. Among the most studied are inflammation, ischaemia-reperfusion injury, and atherogenesis. Lipid peroxidation also plays a dual and complex role in cancer. Organisms have developed an efficient multilevel protective system against lipid peroxidation, but this can be overwhelmed by certain pathologies.

• MeSH
• buněčná membrána metabolismus   MeSH
• DNA metabolismus   MeSH
• lidé MeSH
• lipidové peroxidy metabolismus   MeSH
• organely metabolismus   MeSH
• peroxidace lipidů * MeSH
• proteiny metabolismus   MeSH
• volné radikály MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• DNA MeSH
• lipidové peroxidy MeSH
• proteiny MeSH
• volné radikály MeSH

Elevation of lipid peroxidation (LOX) was observed in rabbits and mice after the intravenous administration of 0.2 micrograms.kg-1 of lipopolysaccharide (LPS) and 100 micrograms.kg-1 of peptidoglycan (MP). The peak was reached sooner after peptidoglycan, and 2-4 h after LPS administration. The trends of lipid peroxidation were the same in both species. 8-10 h later original LOX blood levels were reached. Mild horizontal vibration (1 h) induced in both species a significant lowering of LOX. This appeared already immediately after the vibration. Original values were gained again after 8-10 h. The difference between the internal stressors, LPS and MP, and the external stressor, vibration, are discussed.

• MeSH
• činčila MeSH
• králíci MeSH
• lipidové peroxidy krev   MeSH
• lipidy krev   MeSH
• lipopolysacharidy MeSH
• malondialdehyd krev   MeSH
• myši inbrední CBA MeSH
• myši MeSH
• peptidoglykan MeSH
• peroxidace lipidů fyziologie   MeSH
• psychický stres krev   metabolismus   MeSH
• vibrace škodlivé účinky   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• mužské pohlaví MeSH
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• lipidové peroxidy MeSH
• lipidy MeSH
• lipopolysacharidy MeSH
• malondialdehyd MeSH
• peptidoglykan MeSH

Lipid peroxidation is a major deleterious effect caused by oxidative stress. It is involved in various diseases such as atherosclerosis, rheumatoid arthritis and neurodegenerative diseases. In order to inhibit lipid peroxidation, antioxidants must efficiently scavenge free radicals and penetrate inside biological membranes. Lipocarbazole has recently been shown to be a powerful antioxidant in solution. Here, we show its powerful capacity as lipid peroxidation inhibitor. Its mechanism of action is rationalized based on molecular dynamics simulations on a biomembrane model, quantum calculations and experimental evaluation. The role of the lipocarbazole side chain is particularly highlighted as a critical chemical feature responsible for its antioxidant activity.

• Klíčová slova
• Antioxidant, Lipid bilayer membrane, Lipid peroxidation, Molecular dynamics,
• MeSH
• antioxidancia chemie   metabolismus   MeSH
• karbazoly chemie   metabolismus   MeSH
• kvantová teorie MeSH
• mastné kyseliny chemie   metabolismus   MeSH
• simulace molekulární dynamiky MeSH
• termodynamika MeSH
• unilamelární lipozómy chemie   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antioxidancia MeSH
• carbazole MeSH Prohlížeč
• karbazoly MeSH
• lipid peroxidation inhibitor MeSH Prohlížeč
• mastné kyseliny MeSH
• unilamelární lipozómy MeSH

Measuring absorption spectra of conjugated dienes it has been shown that microwave radiation with a frequency of 2.54 GHz induces lipid peroxidation of phosphatidylcholine liposomes. The relationship with the previously observed microwave-enhanced liposome permeability is discussed.

• MeSH
• fosfatidylcholiny MeSH
• liposomy účinky záření   MeSH
• membrány umělé * MeSH
• mikrovlny * MeSH
• permeabilita buněčné membrány MeSH
• peroxidace lipidů účinky záření   MeSH
• peroxidy chemie   MeSH
• volné radikály MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• fosfatidylcholiny MeSH
• liposomy MeSH
• membrány umělé * MeSH
• peroxidy MeSH
• volné radikály MeSH

Lipid peroxidation is a degenerative oxidative process that modifies the structure of membranes, influencing their biological functions. Lignans, natural polyphenolic antioxidants widely distributed in plants, can prevent this membrane damage by free-radical scavenging. Here, we rationalize the difference in lipid peroxidation inhibition activity of argenteane, a natural dilignan isolated from wild nutmeg, and 3,3'-dimethoxy-1,1'-biphenyl-2,2'-diol, which represents the central part of argenteane responsible for its antioxidant activity. Although both compounds have the same capacity to scavenge free radicals, argenteane is a more active inhibitor of lipid peroxidation. We show that both compounds penetrate into DOPC and PLPC lipid bilayers and adopt similar positions and orientations, which therefore does not explain the difference in their lipid peroxidation inhibition activity. However, free energy profiles indicate that argenteane has a significantly higher affinity to the lipid bilayer, and thus a higher effective concentration to scavenge radicals formed during lipid peroxidation. This finding explains the higher activity of argenteane to inhibit lipid peroxidation.

• MeSH
• antioxidancia chemie   MeSH
• lignany chemie   MeSH
• lipidové dvojvrstvy chemie   MeSH
• peroxidace lipidů MeSH
• termodynamika MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• antioxidancia MeSH
• lignany MeSH
• lipidové dvojvrstvy MeSH

BACKGROUND: Photosystem II proteins of higher plant chloroplasts are prone to oxidative stress, and most prominently the reaction center-binding D1 protein is damaged under abiotic stress. The reactive oxygen species produced under these stress conditions have been suggested to be responsible for the protein injury. SCOPE OF REVIEW: Recently, it has been shown that the primary and secondary products of non-enzymatic and enzymatic lipid peroxidation have a capability to modify photosystem II proteins. Here, we give an overview showing how lipid peroxidation products formed under light stress and heat stress in the thylakoid membranes cause oxidative modification of proteins in higher plant photosystem II. MAJOR CONCLUSIONS: Damage to photosystem II proteins by lipid peroxidation products represents a new mechanism underlying photoinhibition and heat inactivation. GENERAL SIGNIFICANCE: Complete characterization of photosystem II protein damage is of crucial importance because avoidance of the damage makes plants to survive under various abiotic stresses. Further physiological significance of photosystem II protein oxidation by lipid peroxidation product should have a potential relevance to plant acclimation because the oxidized proteins might serve as signaling molecules.

• Klíčová slova
• Lipid peroxidation, Photosystem II, Protein oxidation, Reactive carbonyl species, Reactive oxygen species,
• MeSH
• chloroplasty metabolismus   fyziologie   MeSH
• fotosystém II - proteinový komplex metabolismus   fyziologie   MeSH
• fyziologický stres fyziologie   MeSH
• oxidace-redukce MeSH
• oxidační stres fyziologie   MeSH
• peroxidace lipidů fyziologie   MeSH
• reaktivní formy kyslíku metabolismus   MeSH
• rostliny metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Názvy látek
• fotosystém II - proteinový komplex MeSH
• reaktivní formy kyslíku MeSH

The structural integrity, elasticity, and fluidity of lipid membranes are critical for cellular activities such as communication between cells, exocytosis, and endocytosis. Unsaturated lipids, the main components of biological membranes, are particularly susceptible to the oxidative attack of reactive oxygen species. The peroxidation of unsaturated lipids, in our case 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), induces the structural reorganization of the membrane. We have employed a multi-technique approach to analyze typical properties of lipid bilayers, i.e., roughness, thickness, elasticity, and fluidity. We compared the alteration of the membrane properties upon initiated lipid peroxidation and examined the ability of flavonols, namely quercetin (QUE), myricetin (MCE), and myricitrin (MCI) at different molar fractions, to inhibit this change. Using Mass Spectrometry (MS) and Fourier Transform Infrared Spectroscopy (FTIR), we identified various carbonyl products and examined the extent of the reaction. From Atomic Force Microscopy (AFM), Force Spectroscopy (FS), Small Angle X-Ray Scattering (SAXS), and Electron Paramagnetic Resonance (EPR) experiments, we concluded that the membranes with inserted flavonols exhibit resistance against the structural changes induced by the oxidative attack, which is a finding with multiple biological implications. Our approach reveals the interplay between the flavonol molecular structure and the crucial membrane properties under oxidative attack and provides insight into the pathophysiology of cellular oxidative injury.

• Klíčová slova
• bilayer thickness, elasticity, flavonols, fluidity, lipid peroxidation, myricetin, myricitrin, quercetin,
• Publikační typ
• časopisecké články MeSH

PURPOSE: The effect of physical exercise on lipid peroxidation was investigated. METHOD: 27 healthy young adult male subjects were included in this study. Urine samples were collected before and after exercises. Urinary malondialdehyde and creatinine levels (Cr) were measured. RESULTS: Urinary malondialdehyde levels were increased by exercise. While pre-exercise malondialdehyde levels were 5.02 +/- 1.26 nmol/mg Cr, post-exercise levels were 6.13 +/- 1.84 nmol/mg Cr (p < 0.05). CONCLUSION: These findings indicated that physical exercise induced lipid peroxidation.

• MeSH
• cvičení fyziologie   MeSH
• dospělí MeSH
• kreatinin moč   MeSH
• lidé MeSH
• malondialdehyd moč   MeSH
• mladiství MeSH
• peroxidace lipidů * MeSH
• Check Tag
• dospělí MeSH
• lidé MeSH
• mladiství MeSH
• mužské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kreatinin MeSH
• malondialdehyd MeSH

Lithium is regarded as a unique therapeutic agent for the management of bipolar disorder (BD). In efforts to explain the favourable effects of lithium in BD, a wide range of mechanisms was suggested. Among those, the effect of clinically relevant concentrations of lithium on the plasma membrane was extensively studied. However, the biophysical properties of brain membranes isolated from experimental animals exposed to acute, short-term and chronic lithium have not been performed to-date. In this study, we compared the biophysical parameters and level of lipid peroxidation in membranes isolated from forebrain cortex (FBC) of therapeutic lithium-treated and/or sleep-deprived rats. Lithium interaction with FBC membranes was characterized by appropriate fluorescent probes. DPH (1,6-diphenyl-1,3,5-hexatriene) and TMA-DPH (1-(4-trimethylammoniumphenyl)-6-phenyl-1,3,5-hexatriene p-toluenesulphonate) were used for characterization of the hydrophobic lipid core and Laurdan (6-dodecanoyl-2-dimethylaminonaphthalene) for the membrane-water interface. Lipid peroxidation was determined by immunoblot analysis of 4-HNE-(4-hydroxynonenal)-protein adducts. The organization of polar head-group region of FBC membranes, measured by Laurdan generalized polarization, was substantially altered by sleep deprivation and augmented by lithium treatment. Hydrophobic membrane interior characterized by steady-state anisotropy of DPH and TMA-DPH fluorescence was unchanged. Chronic lithium had a protective effect against peroxidative damage of membrane lipids in FBC. In summary, lithium administration at a therapeutic level and/or sleep deprivation as an animal model of mania resulted in changes in rat FBC membrane properties.

• Klíčová slova
• Lipid bilayer, Lipid peroxidation, Lithium, Membrane fluidity, Rat forebrain cortex,
• MeSH
• bipolární porucha metabolismus   farmakoterapie   MeSH
• buněčná membrána metabolismus   účinky léků   MeSH
• krysa rodu Rattus MeSH
• lipidové dvojvrstvy * metabolismus   MeSH
• lithium farmakologie   MeSH
• peroxidace lipidů * účinky léků   MeSH
• potkani Wistar MeSH
• přední mozek * metabolismus   účinky léků   MeSH
• spánková deprivace * metabolismus   farmakoterapie   MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• lipidové dvojvrstvy * MeSH
• lithium MeSH

The present work was aimed at investigation of lipid peroxidation during fasting and its effects upon metabolism of adipose tissue, especially lipolytic activity. An increase in the lipid peroxidation was demonstrated in an animal model (male rats) through accumulation of lipofuscin-like pigments (LFP), the end product of lipid peroxidation. The increased LFP levels correlated with a decrease in the activity of hormone-sensitive lipase. LFP content increased in the plasma, liver and adipose tissue. The time-course of the changes depended on the initial body mass of the animals. Correlations were found between lipolytic activity and LFP content in adipose tissue and in plasma. In the course of the repeated cycles of fasting--feeding, the changes of LFP and lipolysis were antiparallel to each other. During four cycles, there was a net increase in LFP and a net decrease in lipolysis. The lipolytic activity depended on many factors, among which we identified the initial body mass of animals, their age, and the way of feeding. The results obtained in this animal model enable application of the methods used in the investigation of fasting in obese patients.

• MeSH
• inbrední kmeny potkanů MeSH
• krysa rodu Rattus MeSH
• lipolýza * MeSH
• omezení příjmu potravy * MeSH
• peroxidace lipidů * MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH