The role of alpha-tocopherol in motor hypofunction with aging in alpha-tocopherol transfer protein knockout mice as assessed by oxidative stress biomarkers.

It has been hypothesized that oxidative stress plays a key role in aging. In order to elucidate the role of the antioxidant network - including alpha-tocopherol (alphaT) and alphaT transfer protein - in aging in vivo, alpha-tocopherol transfer protein knockout (alphaTTP(-/-)) mice were fed a vitamin-E-depleted diet, and wild-type (WT) mice were fed a diet containing 0.002 wt.

Evaluation of the antioxidant effects of coffee and its components using the biomarkers hydroxyoctadecadienoic acid and isoprostane.

The association between coffee consumption and its antioxidant effects has not been elucidated in detail. In experimental animals, we used biomarkers to investigate the relationship between coffee consumption and its effects on oxidative stress. We propose a method in which both the free and ester forms of hydroperoxides and ketones as well as the hydroxides of linoleic acid are measured as total hydroxyoctadecadienoic acid (tHODE).

Acceleration of lipid peroxidation in alpha-tocopherol transfer protein-knockout mice following the consumption of drinking water containing a radical initiator.

To assess the antioxidative role of vitamin E (VE) in a mouse model of severe VE deficiency by using biomarkers, alpha-tocopherol transfer protein (alpha-TTP(-/-))-knockout mice were maintained on a VE-deficient diet for 28 weeks [KO group, n = 6]. Wild-type C57BL/6 mice were maintained on a diet containing 0.002% alpha-tocopherol [WT group, n = 6].

Characterization of cellular uptake and distribution of coenzyme Q10 and vitamin E in PC12 cells.

Coenzyme Q (CoQ) is a well-known electron transporter in the mitochondrial respiratory chain. Furthermore, ubiquinol (UQH(2))--a reduced form of ubiquinone (UQ)--has been shown to act as a radical-scavenging antioxidant. Some studies have reported the beneficial effect of CoQ addition to cultured cells; however, the cellular uptake and distribution of CoQ have not been elucidated.

Antioxidant effects of 2,3-dihydro-5-hydroxy-4,6-di-tert-butyl-2,2-dipentylbenzofuran and alpha-tocopherol in hyperlipidemic mice as evaluated by hydroxyoctadecadienoic acid and 7-hydroxycholesterol.

It has been hypothesized that oxidative modification of low density lipoprotein plays a key role in the pathogenesis of atherosclerosis. In order to elucidate the role of lipid oxidation and its inhibition in vivo, apolipoprotein E and alpha-tocopherol (alphaT) transfer protein double knockout (ApoE(-/-)alpha-TTP(-/-)) and apolipoprotein E knockout (ApoE(-/-)) mice fed with a vitamin E-depleted diet and a diet containing 0.002 wt.

Evaluation of lipophilic antioxidant efficacy in vivo by the biomarkers hydroxyoctadecadienoic acid and isoprostane.

The evaluation of antioxidant activity in vivo is difficult. In this study, the effects of dietary natural and synthetic antioxidants on the lipid peroxidation in mice were assessed using a biomarker, total hydroxyoctadecadienoic acid (tHODE). Biological samples such as plasma, erythrocytes, and tissues were first reduced and then saponified to convert various oxidation products of linoleates to tHODE.

Levels of lipid peroxidation in human plasma and erythrocytes: comparison between fatty acids and cholesterol.

Lipid peroxidation has gained renewed attention with increasing evidence showing its biological role in producing toxic compounds and cellular signaling mediators. The assessment of lipid peroxidation levels in vivo is difficult partly because lipids are oxidized by different oxidants by different mechanisms to give versatile types of products, which may undergo metabolism and secondary reactions. In the present study, total hydroxyoctadecadienoic acids (tHODE) and 7alpha- and 7beta-hydroxycholesterol (t7-OHCh) from 44 healthy human subjects were assessed as biomarkers after reduction with sodium borohydride followed by saponification with potassium hydroxide comparing with the prevailing standard 8-isoprostaglandin F(2alpha) (t8-iso-PGF(2alpha)).

Evaluation of the dietary effects of coenzyme Q in vivo by the oxidative stress marker, hydroxyoctadecadienoic acid and its stereoisomer ratio.

Coenzyme Q (CoQ) is an endogenous enzyme cofactor that may provide protective benefits as an antioxidant. In this study, in order to determine whether the concentrations of CoQ(9) are associated with the oxidative status in vivo, the effects of dietary supplements of CoQ(9) on mice were evaluated by using a new biomarker, total hydroxyoctadecadienoic acid (tHODE). Biological samples were first reduced and then saponified to convert the various oxidation products of linoleates to tHODE.

Lipid peroxidation in mice fed a choline-deficient diet as evaluated by total hydroxyoctadecadienoic acid.

Objective: The relevance of oxidative stress in mice fed a choline-deficient diet (CDD) was investigated in relation to the oxidative stress marker, hydroxyoctadecadienoic acid (HODE) in comparison with F2-isoprostanes. Further, the protective effects of antioxidants against oxidative damage were assessed by using HODE.

Methods: We recently proposed total HODE as a biomarker for oxidative stress in vivo.

Total hydroxyoctadecadienoic acid as a marker for lipid peroxidation in vivo.

An improved method for the measurement of lipid peroxidation in vivo has been recently developed, where total hydroxyoctadecadienoic acid (HODE) and 7-hydroxycholesterol (FCOH) were determined by GC/MS analysis from physiological samples after reduction with sodium borohydride and saponification by potassium hydroxide. In this method, both free and ester forms of hydroperoxides and ketones as well as hydroxides of linoleic acid and cholesterol are measured as HODE and FCOH, respectively. The ratio of stereo-isomer, (Z, E)-HODE/(E, E)-HODE, could be also measured.

Lipid peroxidation induced by carbon tetrachloride and its inhibition by antioxidant as evaluated by an oxidative stress marker, HODE.

We have recently proposed total hydroxyoctadecadienoic acid (HODE) as a biomarker for oxidative stress in vivo. The biological samples such as plasma, urine, and tissues were first reduced and then saponified to convert the oxidation products of linoleate to HODE. In the present study, this method was applied to measure the oxidative damage induced by the administration of carbon tetrachloride to mice and also to evaluate the capacity of antioxidant to inhibit the above damage.

Closed-loop analysis of cardiovascular variability in rats under restraint stress.

Causal transfer function analysis was applied to the heart rate variability and blood pressure variability in normotensive male Sprague-Dawley rats those were measured before, during, and after acute restraint stress. The causal transfer gain (CTG) from systolic blood pressure (SBP) to RR interval (RRI) and CTG from RRI to SBP were estimated. The mean value of the CTG from SBP to RRI in the low-frequency (LF) band (0.

Characterization of cellular uptake and distribution of vitamin E.

We previously reported that tocotrienols acted as more potent inhibitors against selenium deficiency-induced cell death than the corresponding tocopherol isoforms (J. Biol. Chem.

Distribution of tocopherols and tocotrienols to rat ocular tissues after topical ophthalmic administration.

With increasing evidence suggesting the involvement of oxidative stress in various disorders and diseases, the role of antioxidants in vivo has received much attention. Chemically, tocopherols and tocotrienols are closely related; however, it has been observed that they have widely varying degrees of biological effectiveness. The present study has been carried out in an attempt to deepen our understanding of whether there is a significant difference in distribution between tocopherol and tocotrienol homologs to rat eye tissues.

Inhibition of plasma lipid peroxidation by anti-atherogenic antioxidant BO-653, 2,3-dihydro-5-hydroxy-4,6-di-tert-butyl-2,2-dipentylbenzofuran.

BO-653, 2,3-dihydro-5-hydroxy-4,6-di-tert-butyl-2,2-dipentylbenzofuran, is a synthetic antioxidant which is now being developed as an anti-atherogenic drug. The antioxidant action of BO-653 against lipid peroxidation in rat plasma was studied and compared with its analogue BO-653M, 2,3-dihydro-5-hydroxy-4,6-di-methyl-2,2-dipentylbenzofuran, and vitamin E. BO-653 was readily incorporated into plasma by oral administration and it inhibited plasma lipid peroxidation more efficiently than vitamin E independent of the presence or absence of vitamin C.

Application of water-soluble radical initiator, 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride, to a study of oxidative stress.

It is essential to generate free radicals at a controled and constant rate for specific duration and at specific site to study the dynamics of oxidation and also antioxidation. Both hydrophilic and lipophilic azo compounds have been used for such purpose. In the present work, the action of 2,2'-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride (AIPH) was examined and compared with those of 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)-propionamide] (AMHP).

[Effective cooperation between clinical physicians and laboratory consultation division].

With the increase in clinical examination items, and with the specialization of clinical medicine, physicians' requests for consultations on laboratory medicine is getting more evident. However, at present in many hospitals laboratory staff do not always make appropriate answers to the questions from physicians in various fields because the laboratories are divided in terms of examination fields. In our hospital, we established a consultation division responding to every inquiry from clinical staff with a full-time technologist.