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1.
J Clin Biochem Nutr ; 60(2): 121-124, 2017 Mar.
Article in English | MEDLINE | ID: mdl-28366991

ABSTRACT

Carnitine is an essential nutrient for the mitochondrial transport of fatty acids. Carnitine deficiency causes a variety of symptoms in multiple organs. Patients with severe motor and intellectual disabilities often have carnitine deficiency. This study aimed to determine the correlation between constipation and carnitine deficiency in them. Patients with severe motor and intellectual disabilities at our hospital were retrospectively reviewed. The correlation between level of free carnitine and severity of constipation was examined. Constipation and non-constipation groups were compared for age; sex; body mass index; bed rest period; use of anti-epileptic drugs, valproate sodium, or enteral nutrition; and serum levels of albumin, pre-albumin, totalcholesterol, free carnitine, folic acid, and trace elements. Moreover, severity of constipation before and after carnitine supplementation was assessed. Twenty-seven patients were enrolled. Of these, 14 were assigned to the constipation group and 13 to the non-constipation group. The free carnitine level was significantly correlated with severity of constipation (R = 0.7604, p<0.01). Free carnitine was significantly lower in the constipation compared with the non-constipation group (p<0.01). No other significant differences between the groups were found. The severity of constipation was significantly relieved after carnitine supplementation (p<0.001). In conclusion, carnitine supplementation could reduce the severity of constipation.

2.
J Clin Biochem Nutr ; 58(3): 223-31, 2016 May.
Article in English | MEDLINE | ID: mdl-27257348

ABSTRACT

In humans, dehydroepiandrosterone and its sulfate ester metabolite DHEA-S are secreted predominantly from the adrenal cortex, and dehydroepiandrosterone is converted to steroid hormones, including androgens and estrogens, and neurosteroid. Dehydroepiandrosterone exerts protective effects against several pathological conditions. Although there are reports on the association between dehydroepiandrosterone and vitamins, the exact relationship between dehydroepiandrosterone and vitamin E remains to be determined. Therefore, we attempted to elucidate the effect of dehydroepiandrosterone on vitamin E status and the expression of various vitamin E-related proteins, including binding proteins, transporters, and cytochrome P450, in vitamin E-deficient rats. Plasma α-tocopherol levels in vitamin E-deficient rats increased in response to dehydroepiandrosterone administration. The expression of hepatic α-tocopherol transfer protein was repressed in vitamin E-deficient rats compared to that in control rats; however, dehydroepiandrosterone administration significantly upregulated this expression. Hepatic expression of CYP4F2, an α-tocopherol metabolizing enzyme, in vitamin E-deficient rats was decreased by dehydroepiandrosterone administration, whereas hepatic expression of ATP-binding cassette transporter A1, an α-tocopherol transporter, was not altered following dehydroepiandrosterone administration. Dehydroepiandrosterone repressed lipid peroxidation in the liver of vitamin E-deficient rats. Therefore, adequate dehydroepiandrosterone supplementation may improve lipid peroxidation under several pathological conditions, and dehydroepiandrosterone may modulate α-tocopherol levels through altered expression of vitamin E-related proteins.

3.
J Nutr Sci Vitaminol (Tokyo) ; 60(4): 239-45, 2014.
Article in English | MEDLINE | ID: mdl-25297612

ABSTRACT

Recently, there has been an increasing concern about noncommunicable diseases (NCDs), in which oxidative damage plays a role. In this paper, we have re-analyzed the data from the National Health and Nutrition Survey (NHNS) 2007 to study the relationship between an NCD (e.g. hypertension) and the dietary intake of vitamin E, a potent anti-oxidative vitamin. The inclusion criteria were those aged 40 and over, excluding pregnant or lactating women, and data from 1,405 males and 2,102 females were analyzed. The mean ages were 63.5 and 62.4, respectively. Nutrients intake was evaluated from a semi-weighted, 1-d household dietary record. When the subjects were categorized into tertiles based on their vitamin E intake, higher vitamin E intake was associated with a lower percentage of subjects with hypertension (p for trend=0.01). Subjects with higher vitamin E intake had higher energy intake-adjusted intake of other nutrients which have been considered to be related to hypertension such as potassium, magnesium, and vitamin C. Logistic regression analysis was done with the low tertile of vitamin E intake as the reference. The medium and high tertiles of vitamin E intake were associated with a significantly lower odds ratio for hypertension, 0.73 (95% CI; 0.62-0.87) for the former and 0.81 (95% CI; 0.69-0.96) for the latter. Additional analyses, one adjusted for the indices associated with hypertension and one excluding the subjects with vitamin E supplementation, have yielded the similar results. In summary, re-analysis of data from NHNS has revealed that higher vitamin E intake was significantly associated with lower prevalence of hypertension.


Subject(s)
Antioxidants/therapeutic use , Diet , Hypertension/prevention & control , Vitamin E/therapeutic use , Vitamins/therapeutic use , Aged , Diet Records , Dietary Supplements , Energy Intake , Female , Humans , Logistic Models , Male , Middle Aged , Nutrition Surveys , Odds Ratio
4.
Am J Med Genet A ; 161A(1): 214-7, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23239635

ABSTRACT

Congenital hypothyroidism (CH), one of the most common congenital endocrine disorders, causes irreversible intellectual disability in untreated patients. Today, the vast majority of patients receive early diagnosis and treatment in the context of newborn screening for CH, and achieve satisfactory cognitive development. However, a subset of patients with delayed onset are undetectable by newborn screening, and miss benefit from early intervention. Here, we report on a delayed-onset CH patient that had two contributing factors in the pathogenesis of CH simultaneously, i.e., a genetic defect and iodine excess. The patient was exposed to excessive iodine in utero because her mother consumed massive amounts of seaweed during pregnancy. Surprisingly, the patient had a negative result in newborn screening, but developed overt CH at age 3 months. She received thyroxine supplementation until when normalization of the thyroid function was confirmed at age 3 years (i.e., transient CH). Mutation screening for DUOX2, a causative gene for transient CH, showed biallelic mutations (p.[E327X] + [H678R]). This report provides a new example of environmental modification of phenotypes of CH due to a genetic defect, which can potentially distort screening results.


Subject(s)
Congenital Hypothyroidism/genetics , Dietary Supplements/adverse effects , Iodine/adverse effects , NADPH Oxidases/genetics , Prenatal Exposure Delayed Effects/genetics , Alleles , Child , Congenital Hypothyroidism/drug therapy , Dual Oxidases , Female , Humans , Infant, Newborn , Iodine/blood , Mutation , Neonatal Screening , Phenotype , Polymerase Chain Reaction , Pregnancy , Prenatal Exposure Delayed Effects/drug therapy , Seaweed , Thyroxine/administration & dosage
5.
Nat Med ; 18(4): 589-94, 2012 Mar 04.
Article in English | MEDLINE | ID: mdl-22388090

ABSTRACT

Bone homeostasis is maintained by the balance between osteoblastic bone formation and osteoclastic bone resorption. Osteoclasts are multinucleated cells that are formed by mononuclear preosteoclast fusion. Fat-soluble vitamins such as vitamin D are pivotal in maintaining skeletal integrity. However, the role of vitamin E in bone remodeling is unknown. Here, we show that mice deficient in α-tocopherol transfer protein (Ttpa(-/-) mice), a mouse model of genetic vitamin E deficiency, have high bone mass as a result of a decrease in bone resorption. Cell-based assays indicated that α-tocopherol stimulated osteoclast fusion, independent of its antioxidant capacity, by inducing the expression of dendritic-cell-specific transmembrane protein, an essential molecule for osteoclast fusion, through activation of mitogen-activated protein kinase 14 (p38) and microphthalmia-associated transcription factor, as well as its direct recruitment to the Tm7sf4 (a gene encoding DC-STAMP) promoter. Indeed, the bone abnormality seen in Ttpa(-/-) mice was rescued by a Tm7sf4 transgene. Moreover, wild-type mice or rats fed an α-tocopherol-supplemented diet, which contains a comparable amount of α-tocopherol to supplements consumed by many people, lost bone mass. These results show that serum vitamin E is a determinant of bone mass through its regulation of osteoclast fusion.


Subject(s)
Bone Resorption/diet therapy , Bone and Bones/drug effects , Osteoclasts/drug effects , Vitamin E Deficiency/pathology , Vitamin E/administration & dosage , Vitamins/administration & dosage , Amino Acids/blood , Animals , Apoptosis/drug effects , Bone Resorption/etiology , Bone Resorption/genetics , Bone and Bones/diagnostic imaging , Bone and Bones/pathology , Bromodeoxyuridine/metabolism , Carrier Proteins/genetics , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Cells, Cultured , Chromatin Immunoprecipitation , Disease Models, Animal , Gene Expression Regulation/drug effects , Humans , In Situ Nick-End Labeling , Macrophage Colony-Stimulating Factor/metabolism , Membrane Proteins/deficiency , Membrane Proteins/genetics , Mice , Mice, Inbred C57BL , Mice, Knockout , Microphthalmia-Associated Transcription Factor/metabolism , Mitogen-Activated Protein Kinase 14/metabolism , Nitrophenols/metabolism , Osteocytes/drug effects , Osteocytes/metabolism , RANK Ligand/metabolism , RNA, Small Interfering/pharmacology , Rats , Signal Transduction/drug effects , Signal Transduction/genetics , Tomography, X-Ray Computed , Transfection , Vitamin E/blood , Vitamin E Deficiency/complications , Vitamin E Deficiency/diet therapy , Vitamin E Deficiency/genetics , Vitamins/blood , alpha-Tocopherol/administration & dosage , alpha-Tocopherol/blood
6.
J Biol Chem ; 287(4): 2926-34, 2012 Jan 20.
Article in English | MEDLINE | ID: mdl-22147702

ABSTRACT

Chloroquine (CQ) is a widely prescribed anti-malarial agent and is also prescribed to treat autoimmune diseases. Clinical treatment with CQ is often accompanied by serious side effects such as hepatitis and retinopathy. As a weak base, CQ accumulates in intracellular acidic organelles, raises the pH, and induces osmotic swelling and permeabilization of acidic organelles, which account for CQ-induced cytotoxicity. We reported previously that CQ treatment caused α-tocopherol transfer protein (α-TTP), a gene product of familial vitamin E deficiency, to change its location from the cytosol to the surface of acidic organelles. Here we show that α-TTP plays a novel role in protecting against CQ toxicity both in vitro and in vivo. In the presence of CQ, rat hepatoma McARH7777 cells, which do not express α-TTP endogenously, showed more severe cytotoxicity, such as larger vacuolation of acidic organelles and caspase activation, than α-TTP transfectant cells. Similarly, α-TTP knockout mice showed more severe CQ toxicity, such as hepatotoxicity and retinopathy, than wild-type mice. These effects were not ameliorated by vitamin E supplementation. In contrast to bafilomycin A1 treatment, which prevents CQ accumulation in cells by raising the pH of acidic organelles, α-TTP expression prevented CQ accumulation without affecting the pH of acidic organelles. Taken together, our data suggest that α-TTP protects against CQ toxicity by preventing CQ accumulation in acidic organelles through a mechanism distinct from vitamin E transport.


Subject(s)
Antimalarials/adverse effects , Carrier Proteins/metabolism , Chloroquine/adverse effects , Drug Resistance , Animals , Antimalarials/pharmacokinetics , Antimalarials/pharmacology , Carrier Proteins/genetics , Cell Line, Tumor , Chemical and Drug Induced Liver Injury/genetics , Chemical and Drug Induced Liver Injury/metabolism , Chloroquine/pharmacokinetics , Chloroquine/pharmacology , Cytosol , Cytotoxins/adverse effects , Cytotoxins/pharmacokinetics , Cytotoxins/pharmacology , Hydrogen-Ion Concentration , Mice , Mice, Knockout , Organelles/genetics , Organelles/metabolism , Protein Transport/drug effects , Protein Transport/genetics , Rats , Retinal Diseases/chemically induced , Retinal Diseases/genetics , Retinal Diseases/metabolism
7.
Free Radic Biol Med ; 50(12): 1801-11, 2011 Jun 15.
Article in English | MEDLINE | ID: mdl-21447382

ABSTRACT

It is widely accepted that oxidative stress is involved in the pathogenesis of Down syndrome, but the effectiveness of antioxidant treatment remains inconclusive. We tested whether chronic administration of α-tocopherol ameliorates the cognitive deficits exhibited by Ts65Dn mice, a mouse model of Down syndrome. α-Tocopherol was administered to pregnant Ts65Dn females, from the day of conception throughout the pregnancy, and to pups over their entire lifetime, from birth to the end of the behavioral testing period. Cognitive deficits were confirmed for Ts65Dn mice fed a control diet, revealing reduced anxiety or regardlessness in the elevated-plus maze task test and spatial learning deficits in the Morris water maze test. However, supplementation with α-tocopherol attenuated both cognitive impairments. In addition, we found that levels of 8-iso-prostaglandin F(2α) in brain tissue and hydroxyoctadecadienoic acid and 7-hydroxycholesterol in the plasma of Ts65Dn mice were higher than those of control mice. Supplementation with α-tocopherol decreased levels of lipid peroxidation products in Ts65Dn mice. Furthermore, we found out that α-tocopherol improved hypocellularity in the hippocampal dentate gyrus of Ts65Dn mice. These results imply that α-tocopherol supplementation from an early stage may be an effective treatment for the cognitive deficits associated with Down syndrome.


Subject(s)
Cognition Disorders/prevention & control , Down Syndrome/drug therapy , Lipid Peroxidation/drug effects , Prenatal Exposure Delayed Effects/prevention & control , alpha-Tocopherol/pharmacology , Animals , Animals, Newborn/genetics , Brain/metabolism , Brain/pathology , Cognition Disorders/drug therapy , Cognition Disorders/etiology , Dinoprost/analogs & derivatives , Dinoprost/metabolism , Disease Models, Animal , Fatty Acids, Unsaturated/metabolism , Female , Free Radicals , Hippocampus/metabolism , Hippocampus/pathology , Hydroxycholesterols/metabolism , Maze Learning/drug effects , Mice , Mice, Neurologic Mutants , Oxidative Stress , Pregnancy , Space Perception/drug effects
8.
J Toxicol Sci ; 34 Suppl 2: SP223-8, 2009.
Article in English | MEDLINE | ID: mdl-19571473

ABSTRACT

Nonalcoholic fatty liver disease (NAFLD) is a state of excessive accumulation of fat in the liver of persons whose alcohol intake is lower than the classical level for causing liver damage. When inflammation and fibrosis occur in addition to fatty liver, followed by the development of chronic hepatic dysfunction, the condition is called non-alcoholic steatohepatitis (NASH). Vitamin E possesses antioxidant activity and is effective for NASH, but the mechanism of action is not known. We utilized a methionine-choline deficiency rat model (MCD rats) to investigate the mechanism by which vitamin E improves NASH. In MCD rats, high-dose vitamin E therapy reduced the hepatic content of thiobarbituric acid-reactive substances, but failed to improve liver histopathology. The hepatic content of alpha-tocopherol was also elevated and this might be related to the expression of alpha-tocopherol transfer protein.


Subject(s)
Antioxidants/therapeutic use , Fatty Liver/drug therapy , Vitamin E/therapeutic use , Animals , Carrier Proteins/metabolism , Choline Deficiency , Disease Models, Animal , Fatty Liver/pathology , Liver/metabolism , Liver/pathology , Male , Methionine/deficiency , Rats , Rats, Wistar , Thiobarbituric Acid Reactive Substances/metabolism , alpha-Tocopherol/metabolism
9.
Pediatr Surg Int ; 25(3): 273-6, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19184049

ABSTRACT

BACKGROUND/PURPOSE: Meconium obstruction of prematurity (MO) often occurs in extremely low-birth weight (ELBW) infants, and its treatment is quite a challenge for neonatologists. We attempted to establish a method of primary treatment for MO of prematurity in ELBW infants. METHODS: An iopamidol enema with 50 cm H(2)O static pressure was performed as the primary treatment. This procedure is safe and effective and we recommend this as the first treatment for MO in ELBW infants. RESULTS: The procedure was performed 50 times in 23 infants and no complications occurred. Out of 23 patients, 20 (88%) improved, but the other 3 did not. In the failure group, the procedure was performed on a significantly later date and the mortality rate was higher (12.5 vs. 67%). CONCLUSIONS: This procedure is safe and effective. We recommend this as the first treatment for MO in ELBW infants.


Subject(s)
Contrast Media/therapeutic use , Enema/methods , Infant, Premature, Diseases/therapy , Intestinal Obstruction/therapy , Iopamidol/therapeutic use , Female , Humans , Infant, Extremely Low Birth Weight , Infant, Newborn , Infant, Premature , Intestinal Obstruction/etiology , Male , Meconium , Retrospective Studies , Treatment Outcome
10.
Brain Res ; 1182: 106-15, 2007 Nov 28.
Article in English | MEDLINE | ID: mdl-17949699

ABSTRACT

Excessive free radical formation has been implicated as one of the causative factors in neurotoxic damage associated with variety of metals, including methylmercury (MeHg). Although the mechanisms associated with MeHg-dependent neurotoxicity remains are unclear, it is known that MeHg leads to neurotoxicity in cerebellar granule cells (CGCs). In vitro exposure of murine CGC primary cultures to MeHg resulted in time- and concentration-dependent cell death. The present study was designed to assess the effect of fat-soluble antioxidant tocopherols and tocotrienols (unsaturated vitamin E) on MeHg-induced neurotoxicity using cultured CGCs. Significant protection from MeHg-induced neuronal cell death was observed with both tocopherols and tocotrienols. Moreover, we observed that tocotrienols are multi-fold more potent than tocopherols in protecting CGCs against MeHg neurotoxicity. At micromolar concentration, tocotrienols, but not tocopherols, showed complete protection by an antioxidant mechanism. Similarly, tocopherols and tocotrienols showed a protective effect on CGCs migration against MeHg-toxicity. These results suggested that oxidative events may contribute to MeHg toxicity in isolated cerebellar granule neurons, and that tocotrienols are potent supplements for pharmacological protection of the developing brain exposed to MeHg.


Subject(s)
Cerebellum/cytology , Methylmercury Compounds/toxicity , Neurons/drug effects , Neuroprotective Agents/therapeutic use , Tocopherols/therapeutic use , Tocotrienols/therapeutic use , Animals , Animals, Newborn , Cell Movement/drug effects , Cell Survival/drug effects , Cells, Cultured , Dose-Response Relationship, Drug , Female , Lipid Peroxidation/drug effects , Mice , Mice, Inbred ICR , Pregnancy , Statistics, Nonparametric , Time Factors
11.
Int Arch Allergy Immunol ; 141(2): 172-80, 2006.
Article in English | MEDLINE | ID: mdl-16899985

ABSTRACT

OBJECTIVE: We investigated the role of antioxidants in airway hyperresponsiveness to acetylcholine using young asthma model mice, which were sensitized and stimulated with ovalbumin. METHODS: The mice had been fed either a normal diet, an alpha-tocopherol-supplemented diet or a probucol-supplemented diet 14 days before the first sensitization. They were immunized with antigen at intervals of 12 days and, starting from 10 days after the second immunization, they were exposed to antigen 3 times every 4th day using an ultrasonic nebulizer. Twenty-four hours after the last antigen inhalation, airway responsiveness to acetylcholine was measured and bronchoalveolar lavage fluid (BALF) was collected. A blood and lung tissue study was also carried out. RESULTS: Twenty-four hours after the last antigen challenge, both IL-4 and IL-5 in the BALF of alpha-tocopherol-supplemented mice were significantly decreased. The IL-5 level in probucol-supplemented mice was also decreased, but there was no difference in IL-4 levels. The serum IgE level was decreased in probucol-supplemented mice. Differential cell rates of the fluid revealed a significant decrease in eosinophils due to antioxidant supplementation. Airway hyperresponsiveness to acetylcholine was also repressed in antioxidant-supplemented mice. In histological sections of lung tissue, inflammatory cells and mucus secretion were markedly reduced in antioxidant-supplemented mice. We investigated the antioxidant effect on our model mice by examining 8-isoprostane in BALF and lung tissue, and acrolein in BALF; however, our experiment gave us no evidence of the antioxidant properties of either alpha-tocopherol or probucol contributing to the reduction of airway inflammation. CONCLUSION: These findings indicate that alpha-tocopherol and probucol suppress allergic responses in asthma model mice, although these two drugs cause suppression in different ways that are unrelated to antioxidation.


Subject(s)
Antioxidants/therapeutic use , Asthma/prevention & control , Bronchial Hyperreactivity/prevention & control , Probucol/therapeutic use , alpha-Tocopherol/therapeutic use , Acrolein/analysis , Allergens/immunology , Animals , Asthma/immunology , Asthma/pathology , Bronchial Hyperreactivity/immunology , Bronchial Provocation Tests , Bronchoalveolar Lavage Fluid/chemistry , Bronchoalveolar Lavage Fluid/cytology , Bronchoalveolar Lavage Fluid/immunology , Dietary Supplements , Dinoprost/analogs & derivatives , Dinoprost/biosynthesis , Disease Models, Animal , Eosinophils/drug effects , Eosinophils/immunology , Female , Hypersensitivity/complications , Hypersensitivity/drug therapy , Immunoglobulin E/blood , Immunoglobulin E/drug effects , Interleukin-4/biosynthesis , Interleukin-4/immunology , Interleukin-5/biosynthesis , Interleukin-5/immunology , Mice , Mice, Inbred BALB C , Ovalbumin/immunology , Oxidative Stress/drug effects , Probucol/blood , alpha-Tocopherol/blood
12.
Eur J Nutr ; 45(6): 320-6, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16699835

ABSTRACT

BACKGROUND: beta-Carotene exhibits biological activity as provitamin A. Key step in vitamin A formation is the cleavage of beta-carotene to retinal by an enzyme designated as beta-carotene 15,15'-monooxygenase (BCM). Recently, it is reported that expression of BCM gene in the intestine is under feedback regulation by retinoic acid (RA). However, the regulation of BCM gene expression in various other tissues is still unknown. AIM OF THE STUDY: In the present study, we identified the full-length cDNA encoding the rat BCM gene and investigated the regulation of its expression in several tissues by RA in the presence of vitamin A deficiency. METHODS: We cloned the full-length cDNA encoding BCM gene from a rat intestinal cDNA library by hybridization screening. The BCM gene expression was examined using Northern blotting and reverse transcription-PCR analysis. We also investigated whether BCM gene expression was regulated by retinoids in several tissues of vitamin A-deficient rats. RESULTS: Sequence analysis of this clone revealed an open reading frame of 1,701 bases encoding a protein of 566 amino acids. The predicted polypeptide showed 94%, 81%, and 66% identity with mouse, human, and chicken BCM, respectively. Rat BCM mRNA was highly expressed in the intestine and liver, while there was weak expression in the testes, kidneys, and lungs. Immunoblotting revealed that rat BCM is a 64-kDa protein. BCM gene expression was increased in the small intestine by vitamin A deficiency compared with that in rats on a control diet, while this upregulation was suppressed by all-trans RA (ATRA) or 9-cis RA (9-cis RA). BCM gene expression in the lungs and testes was also suppressed by ATRA or 9-cis RA in rats with vitamin A deficiency. However, hepatic BCM gene expression was only decreased by ATRA and renal expression was not affected by either retinoid. As the small intestine is the major site of beta-carotene conversion, intestinal BCM gene expression may be more tightly regulated. CONCLUSION: These data suggest that BCM gene expression in several tissues may be down-regulated by RA at the level of conversion of beta-carotene to retinal. To prevent an excess of retinol, homeostasis may occur at the level of conversion of beta-carotene to retinal in several tissues.


Subject(s)
DNA, Complementary/genetics , Gene Expression Regulation, Enzymologic/drug effects , Tretinoin/pharmacology , Vitamin A Deficiency/enzymology , beta-Carotene 15,15'-Monooxygenase/genetics , Amino Acid Sequence , Animals , Cloning, Molecular , Gene Library , Humans , Immunoblotting , Molecular Sequence Data , Open Reading Frames , Organ Specificity , Rats , Reverse Transcriptase Polymerase Chain Reaction , Sequence Homology, Amino Acid , Vitamin A Deficiency/metabolism , beta-Carotene 15,15'-Monooxygenase/metabolism
13.
Osteoporos Int ; 16(12): 1604-10, 2005 Dec.
Article in English | MEDLINE | ID: mdl-15856362

ABSTRACT

Reactive oxygen species (ROS) may contribute to aging and osteoporosis resulting from marked decreases in plasma antioxidants in aged osteoporotic women. On the other hand, high-dose vitamin K2 (menaquinone-4: menatrenone, MK-4) supplementation has been reported to reduce ovariectomy-induced bone loss in rats and to decrease osteoporotic fracture in postmenopausal women. However, the mechanism by which vitamin K2 prevents osteoporosis is unclear. Recently, vitamin K2 has been suggested to preserve antioxidant activity as a novel function. Therefore, we investigated the effect of vitamin K2 on the osteoporosis of aged rats by evaluating the relationships between serum antioxidant levels and bone metabolism. Aged female rats exhibited significantly lower serum alkaline phosphatase activity and osteocalcin level, together with lower serum levels of antioxidants such as 17beta-estradiol, macrophage migration inhibitory factor (MIF) and glutathione peroxidase (GPx) activity, as compared with young female rats. On the other hand, vitamin K2 supplementation (500 mg/kg, food intake) for 98 days led to a significantly increased serum vitamin K2 level (3,045+/-915 ng/ml in the vitamin K2 supplemented group vs. 4.6+/-3.4 ng/ml in the control diet group; P<0.0001) with increased serum alkaline phosphatase activity and MIF level (P<0.05). Unexpectedly, however, it failed to increase the serum level of antioxidants such as GPx. Nor did it affect bone metabolism markers such as osteocalcin and osteopontin, which were significantly lower than in the young female rats (P<0.05). Finally, the histomorphometric properties of the proximal tibia in the femur were not altered by vitamin K2. These results suggest that high-dose vitamin K2 supplementation neither improves lowered antioxidant levels nor stimulates bone formation in aged rats.


Subject(s)
Bone and Bones/metabolism , Dietary Supplements , Osteoporosis/metabolism , Vitamin K 2/administration & dosage , Age Factors , Alkaline Phosphatase/blood , Animals , Antioxidants/analysis , Biomarkers/analysis , Bone and Bones/pathology , Calcium/blood , Female , Glutathione Peroxidase/blood , Osteocalcin/blood , Osteoclasts/pathology , Osteopontin , Osteoporosis/diet therapy , Phosphorus/blood , Rats , Rats, Wistar , Sialoglycoproteins/blood , Vitamin K 2/blood , Weight Gain/drug effects
14.
Pediatr Nephrol ; 19(3): 266-70, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14714169

ABSTRACT

The pathogenesis of nephrotic syndrome is not clear. In this study, we used electron spin resonance (ESR) to evaluate levels of reactive oxygen species in rats with puromycin aminonucleoside (PAN)-induced nephrosis. Twenty-six Wistar rats were divided into four groups: (1) PAN treated, (2) PAN treated and alpha-tocopherol supplemented, (3) supplemented with alpha-tocopherol only, (4) control. On day 9, urinary protein excretion was measured. On day 10, all animals were sacrificed with retrograde perfusion via the aorta to obtain renal venous perfusates. The signal intensities of ascorbate radicals in the perfusates were determined by ESR. After perfusion, the kidneys were isolated and sieved to obtain glomeruli for determination of glomerular thiobarbituric acid-reactive substance (TBArs) and alpha-tocopherol. Urinary protein excretion by PAN-treated rats increased significantly on day 9 and was reduced by alpha-tocopherol supplementation. The ascorbate radical intensity and glomerular TBArs level were higher in PAN-treated than in control rats and were both suppressed to control levels by alpha-tocopherol supplementation. There were positive correlations between ascorbate radical intensity and the daily urinary protein, as well as between ascorbate radical intensity and the glomerular TBArs level. Hence, it is possible to quantify oxidative stress due to PAN nephrosis by ESR. Our findings suggest that lipid peroxidation plays an important role in the pathogenesis of proteinuria in PAN-treated rats.


Subject(s)
Electron Spin Resonance Spectroscopy , Nephrosis/metabolism , Oxidative Stress , Animals , Antibiotics, Antineoplastic , Antioxidants/metabolism , Antioxidants/pharmacology , Male , Nephrosis/diagnosis , Nephrosis/drug therapy , Puromycin Aminonucleoside , Rats , Rats, Wistar , Reactive Oxygen Species/metabolism , Thiobarbituric Acid Reactive Substances/metabolism , alpha-Tocopherol/pharmacology , alpha-Tocopherol/urine
15.
Pediatr Res ; 53(4): 594-9, 2003 Apr.
Article in English | MEDLINE | ID: mdl-12612209

ABSTRACT

Among various hypothetical mechanisms for the in vivo production of reactive oxygen species, transition metal-catalyzed reactions in cooperation with a biologic reducing agent like ascorbic acid or superoxide may be some of the most important. In the present study, we retrospectively examined the existence of non-protein-bound metal ions, an essentially hazardous pro-oxidant form of various transition metals, and the occurrence of metal-catalyzed reactive oxygen species production in cerebrospinal fluid (CSF) of 10 infants with hypoxic ischemic encephalopathy (HIE) subsequent to perinatal asphyxia and 12 control infants within 72 h of birth. Non-protein-bound iron was detected in eight out of 10 CSF samples from the HIE infants and its level was significantly correlated with Sarnat's clinical stage, whereas none of the control infants had detectable non-protein-bound iron levels. Non-protein-bound copper was below the detection limit in all CSF samples from both groups. Ascorbic acid was significantly increased in the CSF of HIE infants when compared with that of controls (means, 664.9 versus 449.4 microM, p = 0.008). ortho-Tyrosine and meta-tyrosine, which are highly specific and sensitive markers of protein oxidation induced by hydroxyl radicals, were significantly higher in HIE infants than in controls when evaluated by the ratio relative to their source amino acid, phenylalanine [means, 110.5 versus 75.4, p = 0.018 for ortho-tyrosine/phenylalanine; 104.6 versus 67.7 (nM/microM x 10(2)), p = 0.048 for meta-tyrosine/phenylalanine]. Both ratios were significantly correlated with non-protein-bound iron, but not with ascorbic acid. Our preliminary observations provide direct evidence that hydroxyl radicals are generated in the CNS during asphyxiation. Iron chelation therapy could be worth developing as a neuroprotective strategy for perinatal asphyxia.


Subject(s)
Copper/cerebrospinal fluid , Hypoxia-Ischemia, Brain/cerebrospinal fluid , Iron/cerebrospinal fluid , Allantoin/cerebrospinal fluid , Ascorbic Acid/cerebrospinal fluid , Biomarkers , Dehydroascorbic Acid/cerebrospinal fluid , Female , Humans , Hydroxyl Radical/cerebrospinal fluid , Infant, Newborn , Male , Oxidative Stress , Protein Binding , Reactive Oxygen Species/cerebrospinal fluid
16.
J Nutr Sci Vitaminol (Tokyo) ; 48(1): 6-9, 2002 Feb.
Article in English | MEDLINE | ID: mdl-12026191

ABSTRACT

We administered high-dose vitamin E to healthy adult male volunteers and assessed the safety of such supplementation. Fourteen volunteers received daily 1,200 IU of vitamin E (800 mg of D-alpha-tocopherol) for 28 d and eight controls were also enrolled. The volunteers treated with vitamin E showed no abnormalities during the study period. The alpha-tocopherol concentrations of plasma and platelets were markedly elevated by vitamin E treatment, but there were no significant differences in platelet aggregation, coagulation, and the clinical parameters between the two groups. In conclusion, a high dose of vitamin E for 28 d had no adverse effects in healthy men.


Subject(s)
Antioxidants/adverse effects , Coronary Artery Disease/prevention & control , Dietary Supplements , Vitamin E/adverse effects , Adult , Antioxidants/administration & dosage , Blood Cell Count , Blood Coagulation/drug effects , Cholesterol/blood , Chromatography, High Pressure Liquid , Humans , Japan , Male , Platelet Aggregation/drug effects , Time Factors , Vitamin E/administration & dosage , Vitamin E/blood , alpha-Tocopherol/blood
17.
Arterioscler Thromb Vasc Biol ; 22(3): 438-42, 2002 Mar 01.
Article in English | MEDLINE | ID: mdl-11884287

ABSTRACT

Coronary risk factors, including age, hypertension, diabetes mellitus, hyperlipidemia, and smoking, are associated with enhanced oxidative stress, which is implicated as a potential mechanism for atherogenesis and atherosclerotic cardiovascular diseases. Male sex is one of the well-known cardiovascular risk factors. We tested the hypothesis that oxidative stress is greater in men than in women. Plasma thiobarbituric acid-reactive substances (TBARS) and urinary 8-isoprostaglandin F2alpha (8-iso-PGF2alpha) were measured in 52 young men and 51 age-matched women. The subjects were healthy, were not smokers, and were not taking any medications or vitamins. Age, blood pressure, plasma cholesterol, and glucose did not differ between the groups. Baseline TBARS (2.32 +/- 0.11 [men] versus 1.87 +/- 0.09 [women] nmol/mL, P<0.01) and 8-iso-PGF2alpha (292 +/- 56 [men] versus 164 +/- 25 [women] pg/mg creatinine, P<0.05) were higher in men than in women. Supplementation of antioxidant vitamins for 4 weeks in men produced a significant reduction in TBARS and 8-iso-PGF2alpha by 34% (P<0.01) and 48% (P<0.05), respectively. Plasma superoxide dismutase, catalase, and vitamin E levels were comparable between the groups. Enhanced oxidative stress in men may provide a biochemical link between male sex and atherosclerotic diseases related to oxidative stress.


Subject(s)
Dinoprost/analogs & derivatives , Oxidative Stress , Premenopause/metabolism , Sex Factors , Adult , Antioxidants/metabolism , Antioxidants/pharmacology , Catalase/blood , Coronary Artery Disease/etiology , Estrogens/blood , F2-Isoprostanes/urine , Female , Humans , Male , Superoxide Dismutase/blood , Thiobarbituric Acid Reactive Substances/analysis , Vitamin D/pharmacology , alpha-Tocopherol/pharmacology
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