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  1. Fulltext Effects of tocotrienol supplementation on hair growth in human volunteers
    Beoy LA, Woei WJ, Hay YK
    Trop Life Sci Res, 2010 Dec;21(2):91-9.
    PMID: 24575202 MyJurnal
    Studies have shown an association between oxidative stress and alopecia. Patients with alopecia generally exhibit lower levels of antioxidants in their scalp area as well as a higher lipid peroxidation index. Tocotrienols belong to the vitamin E family and are known to be potent antioxidants. Hence, a study was conducted to investigate the effect of tocotrienol supplementation on hair growth in volunteers suffering from hair loss. Twenty one volunteers were randomly assigned to orally receive 100 mg of mixed tocotrienols daily while 17 volunteers were assigned to receive placebo capsule orally. The volunteers were monitored for the number of hairs in a pre-determined scalp area as well as the weight of 20 strands of 1 cm length hair clippings at 0 (before supplementation), 4 and 8 months. The number of hairs of the volunteers in the tocotrienol supplementation group increased significantly as compared to the placebo group, with the former recording a 34.5% increase at the end of the 8-month supplementation as compared to a 0.1% decrease for the latter. Nevertheless, the cumulative weight of 20 strands of hair clippings did not differ much from the baseline for both supplementation groups at the end of the study period. In conclusion, this trial demonstrated that supplementation with tocotrienol capsules increases hair number in volunteers suffering from hair loss as compared to the placebo group. This observed effect was most likely to be due to the antioxidant activity of tocotrienols that helped to reduce lipid peroxidation and oxidative stress in the scalp, which are reported to be associated with alopecia.
    Matched MeSH terms: Oxidative Stress
  2. Modulation of oxidative stress by Chlorella vulgaris in streptozotocin (STZ) induced diabetic Sprague-Dawley rats
    Aizzat O, Yap SW, Sopiah H, Madiha MM, Hazreen M, Shailah A, et al.
    Adv Med Sci, 2010;55(2):281-8.
    PMID: 21147697 DOI: 10.2478/v10039-010-0046-z
    Chlorella vulgaris (CV), a fresh water alga has been reported to have hypoglycemic effects. However, antioxidant and anti-inflammatory effects of CV in diabetic animals have not been investigated to date. The aim of the present study was to investigate the role of CV in inflammation and oxidative damage in STZ-induced diabetic rats.
    Matched MeSH terms: Oxidative Stress/drug effects
  3. Fulltext Effect of experimental treatment on GAPDH mRNA expression as a housekeeping gene in human diploid fibroblasts
    Zainuddin A, Chua KH, Abdul Rahim N, Makpol S
    BMC Mol. Biol., 2010;11:59.
    PMID: 20707929 DOI: 10.1186/1471-2199-11-59
    Several genes have been used as housekeeping genes and choosing an appropriate reference gene is important for accurate quantitative RNA expression in real time RT-PCR technique. The expression levels of reference genes should remain constant between the cells of different tissues and under different experimental conditions. The purpose of this study was to determine the effect of different experimental treatments on the expression of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) mRNA so that the reliability of GAPDH as reference gene for quantitative real time RT-PCR in human diploid fibroblasts (HDFs) can be validated. HDFs in 4 different treatment groups viz; young (passage 4), senescent (passage 30), H2O2-induced oxidative stress and gamma-tocotrienol (GTT)-treated groups were harvested for total RNA extraction. Total RNA concentration and purity were determined prior to GAPDH mRNA quantification. Standard curve of GAPDH expression in serial diluted total RNA, melting curve analysis and agarose gel electrophoresis were used to determine the reliability of GAPDH as reference gene.
    Matched MeSH terms: Oxidative Stress/drug effects
  4. Fulltext gamma-Tocotrienol prevents oxidative stress-induced telomere shortening in human fibroblasts derived from different aged individuals
    Makpol S, Abidin AZ, Sairin K, Mazlan M, Top GM, Ngah WZ
    Oxid Med Cell Longev, 2010 Jan-Feb;3(1):35-43.
    PMID: 20716926 DOI: 10.4161/oxim.3.1.9940
    The effects of palm gamma-tocotrienol (GGT) on oxidative stress-induced cellular ageing was investigated in normal human skin fibroblast cell lines derived from different age groups; young (21-year-old, YF), middle (40-year-old, MF) and old (68-year-old, OF). Fibroblast cells were treated with gamma-tocotrienol for 24 hours before or after incubation with IC50 dose of H2O2 for 2 hours. Changes in cell viability, telomere length and telomerase activity were assessed using the MTS assay (Promega, USA), Southern blot analysis and telomere repeat amplification protocol respectively. Results showed that treatment with different concentrations of gamma-tocotrienol increased fibroblasts viability with optimum dose of 80 microM for YF and 40 microM for both MF and OF. At higher concentrations, gamma-tocotrienol treatment caused marked decrease in cell viability with IC50 value of 200 microM (YF), 300 microM (MF) and 100 microM (OF). Exposure to H2O2 decreased cell viability in dose dependent manner, shortened telomere length and reduced telomerase activity in all age groups. The IC50 of H2O2 was found to be; YF (700 microM), MF (400 microM) and OF (100 microM). Results showed that viability increased significantly (p < 0.05) when cells were treated with 80 microM and 40 microM gamma-tocotrienol prior or after H2O2-induced oxidative stress in all age groups. In YF and OF, pretreatment with gamma-tocotrienol prevented shortening of telomere length and reduction in telomerase activity. In MF, telomerase activity increased while no changes in telomere length was observed. However, post-treatment of gamma-tocotrienol did not exert any significant effects on telomere length and telomerase activity. Thus, these data suggest that gamma-tocotrienol protects against oxidative stress-induced cellular ageing by modulating the telomere length possibly via telomerase.
    Matched MeSH terms: Oxidative Stress/drug effects*
  5. Fulltext Does chlorella vulgaris modulate the expression of col and mmp genes in skin ageing?
    Loke, C.Y., Nur Hidayah, M.S., Mohd Fadhli, M.F., Teo, SK, Nor Hidayah, A.G., Yasmin Anum, M.Y., et al.
    Medicine & Health, 2010;5(1):1-12.
    MyJurnal
    Chlorella vulgaris, a unicellular microalgae, produces many intracellular phytochemicals namely carotenoids, tocopherols, ubiquinone and protein. Skin ageing which is induced by oxidative stress involves decreased extracellular matrix synthesis and increased expression of enzymes that degrade the collagenous matrix. The objective of this study was to determine the effect of C. vulgaris on the expression of genes encoded for collagen (COL) and matrix metalloproteinases (MMPs) which are involved in skin ageing. Human diploid fibroblasts (HDFs) were obtained from circumcision foreskin of 8-12 year-old boys. HDFs were cultured into 3 groups: untreated control cells, cells with stress-induced premature senescence (SIPS; cells were induced with H2O2 at passage 6 for 2 weeks) and SIPS treated with C. vulgaris (prolonged C. vulgaris treatment started at passage 4 and combined treatment with H2O2 at passage 6 for 2 weeks). Senescence-associated ß-galactosidase (SA ß-gal) was determined using senescent cells histochemical staining kit (Sigma, USA). Expression of COLI, COLIII, COLIV, MMPI, MMPII and MMPIII genes was quantitatively analysed with real-time RT-PCR method (iScript™ One Step real-time PCR with SYBR® Green; Biorad). HDFs treated with H2O2 (SIPS) exhibited senescent morphological features of flattening and enlarged with increased expression of SA ß-gal (p
    Matched MeSH terms: Oxidative Stress
  6. Chelation therapy with desferrioxamine does not normalize ferritin level but attenuates oxidative damage and improves total antioxidant level in Malaysian Chinese beta-thalassaemia major patients
    Kuppusamy UR, Tan JA
    West Indian Med J, 2011 Jan;60(1):3-8.
    PMID: 21809703
    Beta-thalassaemia major causes severe anaemia and patients with it may be transfusion-dependent for life. Regular blood transfusions cause iron-overload that leads to oxidative damage which can hasten mortality. The objective of this research was to study the oxidant-antioxidant indices in beta-thalassaemia major patients at the University of Malaya Medical Centre (UMMC) who were on desferrioxamine-chelation or without chelation therapy. Blood was collected from 39 Chinese patients and 20 controls. Plasma and peripheral blood mononuclear cell lysates (PBMC) were extracted and biochemical tests to evaluate oxidative stress were performed. Oxidative stress was evident in these patients as advanced oxidized protein products (AOPP) and lipid hydroperoxides were elevated, whereas glutathione peroxidase activity and the ferric reducing antioxidant power (FRAP) were reduced. The catalase activity in the patients' PBMC was elevated, possibly as a compensatory mechanism for the reduced glutathione peroxidase activity in both red blood cells and PBMC. The lower FRAP and higher AOPP levels in the non-chelated patients compared with the chelated patients were indicative of a lower oxidative stress level in the chelated patients. The ferritin levels in the chelated and non-chelated patients were high and the mean levels of liver enzyme activities in the majority of patients were elevated regardless of chelation therapy. In conclusion, this study indicates that desferrioxamine chelation therapy does not normalize ferritin level but attenuates oxidative damage and improves total antioxidant level in Malaysian Chinese beta-thalassaemia major patients.
    Matched MeSH terms: Oxidative Stress/drug effects
  7. Fulltext Biomedical studies on lipid peroxidation and erythrocyte fragility during the process of aging
    Kumar A
    Asian Pac J Trop Biomed, 2011 Jan;1(1):6-7.
    PMID: 23569715 DOI: 10.1016/S2221-1691(11)60058-0
    To investigate oxidative stress, hemoglobin percentage and erythrocyte osmotic fragility in various aging groups.
    Matched MeSH terms: Oxidative Stress
  8. Decreased glutamine synthetase, increased citrulline-nitric oxide cycle activities, and oxidative stress in different regions of brain in epilepsy rat model
    Swamy M, Yusof WR, Sirajudeen KN, Mustapha Z, Govindasamy C
    J Physiol Biochem, 2011 Mar;67(1):105-13.
    PMID: 20960085 DOI: 10.1007/s13105-010-0054-2
    To understand their role in epilepsy, the nitric oxide synthetase (NOS), argininosuccinate synthetase (AS), argininosuccinate lyase (AL), glutamine synthetase (GS), and arginase activities, along with the concentration of nitrate/nitrite (NOx), thiobarbituric acid reactive substances (TBARS), and total antioxidant status (TAS), were estimated in different regions of brain in rats subjected to experimental epilepsy induced by subcutaneous administration of kainic acid (KA). The short-term (acute) group animals were killed after 2 h and the long term (chronic) group animals were killed after 5 days of single injection of KA (15 mg/kg body weight). After decapitation of rats, the brain regions were separated and in their homogenates, the concentration of NOx, TBARS and TAS and the activities of NOS, AS, AL, arginase and glutamine synthetase were assayed by colorimetric methods. The results of the study demonstrated the increased activity of NOS and formation of NO in acute and chronic groups epilepsy. The activities of AS and AL were increased and indicate the effective recycling of citrulline to arginine. The activity of glutamine synthetase was decreased in acute and chronic groups of epilepsy compared to control group and indicate the modulation of its activity by NO in epilepsy. The activity of arginase was not changed in acute group; however it was decreased in chronic group and may favor increased production of NO in this condition. The concentration TBARS were increased and TAS decreased in acute and chronic groups of epilepsy and supports the oxidative stress in epilepsy.
    Matched MeSH terms: Oxidative Stress*
  9. Effect of four different vegetable oils (red palm olein, palm olein, corn oil, coconut oil) on antioxidant enzymes activity of rat liver
    Dauqan E, Sani HA, Abdullah A, Kasim ZM
    Pak J Biol Sci, 2011 Mar 15;14(6):399-403.
    PMID: 21902064
    The objective of the study was to evaluate the effect of four different vegetable oils [red palm olein (RPO), palm olein (PO), corn oil (CO), coconut oil (COC)] on antioxidant enzymes activity of rat liver. Sixty six Sprague Dawley male rats which were randomly divided into eleven groups of 6 rats per group and were treated with 15% of RPO, PO, CO and COC for 4 and 8 weeks. Rats in the control group were given normal rat pellet only while in treated groups, 15% of additional different vegetable oils were given. After 4 weeks of treatment the catalase (CAT) activity results showed that there was no significance difference (p > or = 0.05) between the control group and treated groups while after 8 weeks of treatment showed that there was no significant different (p > or = 0.05) between control group and RPO group but the treated rat liver with PO, CO and COC groups were the lowest and it were significantly lower (> or = 0.05) than control group. For superoxide dismutase (SOD) there was no significance difference (p > or = 0.05) between the control group and treated groups of vegetable oils after 4 and 8 weeks of treatment. Thus the study indicated that there was no significant (p > or = 0.05) effect on antioxidant enzyme (superoxide dismutase) but there was significant effect (p > or = 0.05) on catalase in rat liver.
    Matched MeSH terms: Oxidative Stress/drug effects
  10. Tualang honey has higher phenolic content and greater radical scavenging activity compared with other honey sources
    Kishore RK, Halim AS, Syazana MS, Sirajudeen KN
    Nutr Res, 2011 Apr;31(4):322-5.
    PMID: 21530807 DOI: 10.1016/j.nutres.2011.03.001
    Many chronic diseases are associated with increased oxidative stress caused by an imbalance between free-radical production and the antioxidant level. Antioxidants, which are abundant in natural honey, are free-radical scavengers that either reduce the formation of or neutralize free radicals. The composition and source of honey greatly dictates its biochemical properties. We performed a comparative analysis of the total phenolic content and antioxidant potential of common commercially available honeys along with Malaysian tualang honey. In vitro biochemical analysis of the phenolic content by the Folin-Ciocalteau method revealed a significantly elevated phenolic content (83.96 ± 4.53 mg gallic acid equivalents per 100 g) in tualang honey. In addition, the antioxidant capacity (53.06 ± 0.41 mg ascorbic acid equivalents per gram) of tualang honey was greater, as assessed by the phosphomolybdenum method, 2,2-diphenyl-1-picryl-hydrazyl assay, and ferric reducing/antioxidant power assay. Peroxynitrite and superoxide radical scavenging activity was determined by spectrophotometric analysis in different honey types. Our data suggest that the elevated free-radical scavenging and antioxidant activity observed in tualang honey is due to the increased level of phenolic compounds. In addition to its antibacterial, anticarcinogenic, and anti-inflammatory properties, our study highlights the favorable antioxidant properties of tualang honey, which may be important to human nutrition and health.
    Matched MeSH terms: Oxidative Stress
  11. Minocycline attenuates the development of diabetic neuropathic pain: possible anti-inflammatory and anti-oxidant mechanisms
    Pabreja K, Dua K, Sharma S, Padi SS, Kulkarni SK
    Eur J Pharmacol, 2011 Jul 1;661(1-3):15-21.
    PMID: 21536024 DOI: 10.1016/j.ejphar.2011.04.014
    Painful neuropathy, a common complication of diabetes mellitus is characterized by allodynia and hyperalgesia. Recent studies emphasized on the role of non-neuronal cells, particularly microglia in the development of neuronal hypersensitivity. The purpose of the present study is to evaluate the effect of minocyline, a selective inhibitor of microglial activation to define the role of neuroimmune activation in experimental diabetic neuropathy. Cold allodynia and thermal and chemical hyperalgesia were assessed and the markers of inflammation and oxidative and nitrosative stress were estimated in streptozotocin-induced diabetic rats. Chronic administration of minocycline (40 and 80 mg/kg, i.p.) for 2 weeks started 2 weeks after diabetes induction attenuated the development of diabetic neuropathy as compared to diabetic control animals. In addition, minocyline treatment reduced the levels of interleukin-1β and tumor necrosis factor-α, lipid peroxidation, nitrite and also improved antioxidant defense in spinal cords of diabetic rats as compared to diabetic control animals. In contrast, minocycline (80 mg/kg, per se) had no effect on any of these behavioral and biochemical parameters assessed in age-matched control animals. The results of the present study strongly suggest that activated microglia are involved in the development of experimental diabetic neuropathy and minocycline exerted its effect probably by inhibition of neuroimmune activation of microglia. In addition, the beneficial effects of minocycline are partly mediated by its anti-inflammatory effect by reducing the levels of proinflammatory cytokines and in part by modulating oxidative and nitrosative stress in the spinal cord that might be involved in attenuating the development of behavioral hypersensitivity in diabetic rats.
    Matched MeSH terms: Oxidative Stress/drug effects
  12. Resistance against apoptosis by the cellular prion protein is dependent on its glycosylation status in oral HSC-2 and colon LS 174T cancer cells
    Yap YH, Say YH
    Cancer Lett, 2011 Jul 1;306(1):111-9.
    PMID: 21439722 DOI: 10.1016/j.canlet.2011.02.040
    Most studies have focused on the role of the cellular prion protein (PrP(C)) in neurodegenerative diseases, whereas the function of this ubiquitous protein outside the nervous system remains elusive. Therefore, the anti-apoptotic property of PrP(C) in oral squamous cell carcinoma (HSC-2) and colon adenocarcinoma (LS 174T) was evaluated in this study, by stable shRNA knockdown and overexpression, respectively. PrP(C) confers resistance against oxidative stress-apoptosis as indicated by MTT assay, Annexin V-FITC/PI and DCFH-DA staining, but this property is abolished upon N-glycosylation inhibition by tunicamycin. Our results indicate that the inhibition of glycosylation in cancer cells overexpressing PrP(C) could represent a potential therapeutic target.
    Matched MeSH terms: Oxidative Stress
  13. Differential expression of oil palm pathology genes during interactions with Ganoderma boninense and Trichoderma harzianum
    Alizadeh F, Abdullah SN, Khodavandi A, Abdullah F, Yusuf UK, Chong PP
    J Plant Physiol, 2011 Jul 01;168(10):1106-13.
    PMID: 21333381 DOI: 10.1016/j.jplph.2010.12.007
    The expression profiles of Δ9 stearoyl-acyl carrier protein desaturase (SAD1 and SAD2) and type 3 metallothionein (MT3-A and MT3-B) were investigated in seedlings of oil palm (Elaeis guineensis) artificially inoculated with the pathogenic fungus Ganoderma boninense and the symbiotic fungus Trichoderma harzianum. Expression of SAD1 and MT3-A in roots and SAD2 in leaves were significantly up-regulated in G. boninense inoculated seedlings at 21 d after treatment when physical symptoms had not yet appeared and thereafter decreased to basal levels when symptoms became visible. Our finding demonstrated that the SAD1 expression in leaves was significantly down-regulated to negligible levels at 42 and 63 d after treatment. The transcripts of MT3 genes were synthesized in G. boninense inoculated leaves at 42 d after treatment, and the analyses did not show detectable expression of these genes before 42 d after treatment. In T. harzianum inoculated seedlings, the expression levels of SAD1 and SAD2 increased gradually and were stronger in roots than leaves, while for MT3-A and MT3-B, the expression levels were induced in leaves at 3d after treatment and subsequently maintained at same levels until 63d after treatment. The MT3-A expression was significantly up-regulated in roots at 3d after treatment and thereafter were maintained at this level. Both SAD and MT3 expression were maintained at maximum levels or at levels higher than basal. This study demonstrates that oil palm was able to distinguish between pathogenic and symbiotic fungal interactions, thus resulting in different transcriptional activation profiles of SAD and MT3 genes. Increases in expression levels of SAD and MT3 would lead to enhanced resistance against G. boninense and down-regulation of genes confer potential for invasive growth of the pathogen. Differences in expression profiles of SAD and MT3 relate to plant resistance mechanisms while supporting growth enhancing effects of symbiotic T. harzianum.
    Matched MeSH terms: Oxidative Stress
  14. Neuroprotective effect of bioflavonoid quercetin in 6-hydroxydopamine-induced oxidative stress biomarkers in the rat striatum
    Haleagrahara N, Siew CJ, Mitra NK, Kumari M
    Neurosci Lett, 2011 Aug 15;500(2):139-43.
    PMID: 21704673 DOI: 10.1016/j.neulet.2011.06.021
    An increasing large body of research on Parkinson's disease (PD) has focused on the understanding of the mechanisms behind the potential neuro protection offered by antioxidants and iron chelating agents. In this study, the protective effect of the bioflavonoid quercetin on 6-hydroxydopamine (6-OHDA)-induced model of PD was investigated. PD was induced by a single intracisternal injection of 6-hydroxydopamine (300μg) to male Sprague-Dawley rats. Quercetin treatment (30mg/kg body weight) over 14 consecutive days markedly increased the striatal dopamine and antioxidant enzyme levels compared with similar measurements in the group treated with 6-OHDA alone. There was a significant decrease in protein carbonyl content in the striatum compared with that of rats that did not receive quercetin. A significant increase in neuronal survivability was also found with quercetin treatment in rats administered 6-OHDA. In conclusion, treatment with quercetin defended against the oxidative stress in the striatum and reduced the dopaminergic neuronal loss in the rat model of PD.
    Matched MeSH terms: Oxidative Stress/drug effects*
  15. Modulation of C-reactive protein and tumour necrosis factor-α in collagen-induced arthritis in Dark Agouti rats: impact of collagen concentration on severity of arthritis
    Tudave D, Radhakrishnan A, Chakravarthi S, Haleagrahara N
    Inflamm Res, 2011 Oct;60(10):897-907.
    PMID: 21633874 DOI: 10.1007/s00011-011-0349-y
    OBJECTIVES: The study investigated the effect of collagen-induced arthritis in Dark Agouti (DA) rats on the level of C-reactive protein and inflammatory cytokine tumour necrosis factor-alpha (TNF-α).

    SUBJECTS: Female Dark Agouti (DA) rats.

    METHODS: Three different dosages of (2 mg/kg of body weight, 3 mg/kg of body weight and 4 mg/kg of body weight) collagen and complete Freund's adjuvant suspension were tested. After 45 days, serum C-reactive protein, TNF-α, superoxide dismutase and total glutathione assays were done. Radiographic and histopathological changes in the joints were compared.

    RESULTS: All three groups showed signs of arthritic changes, confirmed by histopathological and radiographic changes. Severe arthritic changes were seen in the rats injected with 4 mg/kg of body weight of collagen. There was a significant increase in C-reactive protein, TNF-α, super oxide dismutase and total glutathione levels in the plasma in arthritis rats and the changes were more significant with 4 mg/kg of collagen.

    CONCLUSION: These results demonstrated that the optimal dose to inject to experimental animals in order to get server arthritic changes was 4 mg/kg of collagen with complete Freund's adjuvant suspension. Severe arthritis changes induced significant elevation in plasma C-reactive protein and TNF-α levels.

    Matched MeSH terms: Oxidative Stress
  16. Evaluating the toxic and beneficial effects of jering beans (Archidendron jiringa) in normal and diabetic rats
    Shukri R, Mohamed S, Mustapha NM, Hamid AA
    J Sci Food Agric, 2011 Nov;91(14):2697-706.
    PMID: 21744354 DOI: 10.1002/jsfa.4516
    Jering (Archidendron jiringa) is eaten in the tropics and traditionally extolled for treating diabetes, high blood pressure and eliminating bladder stones. Jering contains an unusual amino acid-djenkolic acid (S,S'-methylenebiscysteine)-which may form sharp crystals in the urinary tract, causing pain and haematuria. This study evaluates the beneficial and toxic effects of dietary jering on tissues and organs in normal and diabetic rats.
    Matched MeSH terms: Oxidative Stress
  17. Fulltext Effects of α-tocopherol on the early phase of osteoporotic fracture healing
    Shuid AN, Mohamad S, Muhammad N, Fadzilah FM, Mokhtar SA, Mohamed N, et al.
    J Orthop Res, 2011 Nov;29(11):1732-8.
    PMID: 21547940 DOI: 10.1002/jor.21452
    Fracture healing is a complex process, which is more complicated if the bone is osteoporotic. One of the vitamin E isomers, α-tocopherol, has been found to prevent osteoporosis and improve bone fracture healing but its role in the healing of osteoporotic fractures is still unclear. We carried out a study on the effects of α-tocopherol supplementation on osteoporotic fracture healing using an ovariectomized rat model, whereby we focused on the early phase of fracture healing, that is, the phase with excessive production of free radicals. Twenty-four female Sprague-Dawley rats were divided into three groups: sham-operated (SO), ovariectomized-control (OVC), and ovariectomized + α-tocopherol supplementation (ATF) groups. The right femora of all the rats were fractured at mid-diaphysis and K-wires were inserted for internal fixation. After 2 weeks of treatment, the rats were euthanized and the femora were dissected out for measurement of callous volume by CT-scan and radiological staging of callous formation and fracture healing. The oxidative parameters of the fractured femora were also measured. The results showed that the callous volume and callous staging were not different between the groups. However, the fracture healing stage of the OVC group was lower than the SO group, while α-tocopherol supplementation in the ATF group had improved the healing until it was comparable to the SO group. The activities of the anti-oxidatant enzymes, superoxide dismutase, and glutathione peroxidase in the ATF group were found to be significantly higher than in the OVC group. In conclusion, α-tocopherol improved fracture healing but had no effect on the callous volume and staging. The improvement in fracture healing may be due to the increased activities of the anti-oxidatant enzymes in the bone during the early phase of fracture healing of osteoporotic bone.
    Matched MeSH terms: Oxidative Stress/drug effects
  18. Neuroprotection of α-synuclein under acute and chronic rotenone and maneb treatment is abolished by its familial Parkinson's disease mutations A30P, A53T and E46K
    Choong CJ, Say YH
    Neurotoxicology, 2011 Dec;32(6):857-63.
    PMID: 21658409 DOI: 10.1016/j.neuro.2011.05.012
    α-Synuclein (α-Syn) plays a crucial role in the pathophysiology of Parkinson's disease (PD). α-Syn has been extensively studied in many neuronal cell-based PD models but has yielded mixed results. The objective of this study was to re-evaluate the dual cytotoxic/protective roles of α-Syn in dopaminergic SH-SY5Y cells. Stable SH-SY5Y cells overexpressing wild type or familial α-Syn mutants (A30P, E46K and A53T) were subjected to acute and chronic rotenone and maneb treatment. Compared with untransfected SH-SY5Y cells, wild type α-Syn attenuated rotenone and maneb-induced cell death along with an attenuation of toxin-induced mitochondrial membrane potential changes and Reactive Oxygen Species level, whereas the mutant α-Syn constructs exacerbated environmental toxins-induced cytotoxicity. After chronic treatment, wild type α-Syn but not the mutant variants was found to rescue cells from subsequent acute hydrogen peroxide insult. These results suggest that the fundamental property of wild type α-Syn may be protective, and such property may be lost by its familial PD mutations.
    Matched MeSH terms: Oxidative Stress/drug effects
  19. Selenium supplementation reduced oxidative stress in diethylnitrosamine-induced hepatocellular carcinoma in rats
    Mohamed J, Wei WL, Husin NN, Alwahaibi NY, Budin SB
    Pak J Biol Sci, 2011 Dec 01;14(23):1055-60.
    PMID: 22590839
    Selenium in the form of sodium selenite (SSE) is an essential micronutrient which known to possess antioxidant and anticancer properties. This study emphasizes the role of selenium on oxidative stress in experimental rats with N-diethylnitrosamine (DEN) initiated and 2-acetylaminofluorene (2-AAF) promoted multistage hepatocellular carcinogenesis (HCC). Rats were divided randomly into six groups: negative control, positive control (DEN+2-AAF), preventive group (pre-SEE 4 weeks+DEN), preventive control (respective control for preventive group), therapeutic group (DEN+post-SSE 12 weeks) and therapeutic control (respective control for therapeutic group). SSE (4 mg L(-1)) was given to animals before initiation and during promotion phase of HCC. The levels of total protein (TP), conjugated diens (CD), malondialdehyde (MDA), fluorescent pigment (FP), antioxidant activity (AOA) and DNA damage were measured. Supplementation of SSE before the initiation phase of carcinogenicity significantly increased TP and AOA level (p < 0.05) while it decreased the levels of CD, MDA, DNA damage and FP (p < 0.05). Supplementation of SSE during the promotion phase of carcinogenicity significantly decreased the DNA damage and FP level (p < 0.05) and there were negative correlation between the level of AOA and with the level of FP and CD. Thus, supplementation of SSE reduced the adverse changes which occur in liver cancer. However, the chemoprevention effect of SSE was more pronounced when it was supplemented before initiation phase of cancer when compared to promotion phase.
    Matched MeSH terms: Oxidative Stress/drug effects*
  20. Tocotrienol rich fraction (TRF) supplementation protects against oxidative DNA damage and improves cognitive functions in Wistar rats
    Taridi NM, Yahaya MF, Teoh SL, Latiff AA, Ngah WZ, Das S, et al.
    Clin Ter, 2011;162(2):93-8.
    PMID: 21533313
    Oxidative stress is caused by imbalance between the productions of reactive oxygen species (ROS) and antioxidant defense mechanisms. Palm oil antioxidants such as tocotrienol rich fraction (TRF) is known to have neuroprotective effects on neurones by acting against free radical induced neuronal cell death. This study was undertaken to elucidate the effect of TRF on oxidative DNA damage and cognitive functions in experimental rats.
    Matched MeSH terms: Oxidative Stress/drug effects*
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