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  1. Involvement of TRPM2 Channel on Hypoxia-Induced Oxidative Injury, Inflammation, and Cell Death in Retinal Pigment Epithelial Cells: Modulator Action of Selenium Nanoparticles
    Özkaya D, Nazıroğlu M, Vanyorek L, Muhamad S
    Biol Trace Elem Res, 2021 Apr;199(4):1356-1369.
    PMID: 33389617 DOI: 10.1007/s12011-020-02556-3
    Hypoxia (HYPX) in several eye diseases such as glaucoma and diabetic retinopathy causes oxidative cell death and inflammation. TRPM2 cation channel is activated by HYPX-induced ADP-ribose (ADPR) and oxidative stress. The protective role of selenium via inhibition of TRPM2 on the HYPX-induced oxidative cytotoxicity and inflammation values in the human kidney cell line was recently reported. However, the protective role of selenium nanoparticles (SeNP) on the values in the retinal pigment epithelial (ARPE-19) cells has not been clarified yet. In the current study, we investigated two subjects. First, we investigated the involvement of TRPM2 channel on the HYPX-induced oxidative injury, inflammation, and apoptosis in the ARPE-19 cells. Second, we investigated the protective role of SeNP via inhibition of TRPM2 channel on the HYPX-induced oxidative injury and apoptosis in the ARPE-19 cells. For the aims, the ARPE-19 cells were divided into four main groups as follows: Control (Ctr), SeNP (2.5 μg/ml for 24 h), HYPX (200 μM CoCl2 for 24 h), and HYPX+SeNP. The TRPM2 current density and Ca2+ fluorescence intensity with an increase of mitochondrial membrane depolarization and oxygen free radical (OFR) generations were increased in the ARPE-19 cells by the treatment of HYPX. There was no increase of Ca2+ fluorescence intensity in the pre-treated cells with PARP-1 inhibitors (DPQ and PJ34) or in the presence of Ca2+-free extracellular buffer. When HYPX-induced TRPM2 activity was treated by SeNP and TRPM2 (2-APB and ACA) blockers, the increases of OFR generation, cytokine (TNF-α and IL-1β) levels, TRPM2, and PARP-1 expressions were restored. In conclusion, the exposure of HYPX caused mitochondrial oxidative cell cytotoxicity and cell death via TRPM2-mediated Ca2+ signaling and may provide an avenue for treating HYPX-induced retinal diseases associated with the excessive OFR and Ca2+ influx.
    Matched MeSH terms: Oxidative Stress*
  2. Fulltext Antioxidant and Neuroprotective Effects Induced by Cannabidiol and Cannabigerol in Rat CTX-TNA2 Astrocytes and Isolated Cortexes
    di Giacomo V, Chiavaroli A, Recinella L, Orlando G, Cataldi A, Rapino M, et al.
    Int J Mol Sci, 2020 05 18;21(10).
    PMID: 32443623 DOI: 10.3390/ijms21103575
    Cannabidiol (CBD) and cannabigerol (CBG) are Cannabis sativa terpenophenols. Although CBD's effectiveness against neurological diseases has already been demonstrated, nothing is known about CBG. Therefore, a comparison of the effects of these compounds was performed in two experimental models mimicking the oxidative stress and neurotoxicity occurring in neurological diseases. Rat astrocytes were exposed to hydrogen peroxide and cell viability, reactive oxygen species production and apoptosis occurrence were investigated. Cortexes were exposed to K+ 60 mM depolarizing stimulus and serotonin (5-HT) turnover, 3-hydroxykinurenine and kynurenic acid levels were measured. A proteomic analysis and bioinformatics and docking studies were performed. Both compounds exerted antioxidant effects in astrocytes and restored the cortex level of 5-HT depleted by neurotoxic stimuli, whereas sole CBD restored the basal levels of 3-hydroxykinurenine and kynurenic acid. CBG was less effective than CBD in restoring the levels of proteins involved in neurotransmitter exocytosis. Docking analyses predicted the inhibitory effects of these compounds towards the neurokinin B receptor. Conclusion: The results in the in vitro system suggest brain non-neuronal cells as a target in the treatment of oxidative conditions, whereas findings in the ex vivo system and docking analyses imply the potential roles of CBD and CBG as neuroprotective agents.
    Matched MeSH terms: Oxidative Stress
  3. Fulltext Vitamin E (α-Tocopherol) Exhibits Antitumour Activity on Oral Squamous Carcinoma Cells ORL-48
    Zulkapli R, Abdul Razak F, Zain RB
    Integr Cancer Ther, 2017 09;16(3):414-425.
    PMID: 28818030 DOI: 10.1177/1534735416675950
    Cancers involving the oral cavity, head, and neck regions are often treated with cisplatin. In cancer therapy, the main target is to eliminate unwanted cancerous cells. However, reports on the nonselective nature of this drug have raised few concerns. Incorrect nutritional habits and lifestyle practices have been directly linked to cancer incidence. Nutrients with antioxidant activity inhibit cancer cells development, destroying them through oxidative stress and apoptosis. α-tocopherol, the potent antioxidant form of vitamin E is a known scavenger of free radicals. In vitro study exhibited effective antitumor activity of α-tocopherol on ORL-48 at 2.5 ± 0.42 µg/mL. Cisplatin exhibited stronger activity at 1.0 ± 0.15 µg/mL, but unlike α-tocopherol it exhibited cytotoxicity on normal human epidermal keratinocytes at very low concentration (<0.1 µg/mL). Despite the lower potency of α-tocopherol, signs of apoptosis such as the shrinkage of cells and appearance of apoptotic bodies were observed much earlier than cisplatin in time lapse microscopy. No apoptotic vesicles were formed with cisplatin, instead an increased population of cells in the holoclone form which may suggest different induction mechanisms between both agents. High accumulation of cells in the G0/G1 phase were observed through TUNEL and annexin V-biotin assays, while the exhibition of ultrastructural changes of the cellular structures verified the apoptotic mode of cell death by both agents. Both cisplatin and α-tocopherol displayed cell cycle arrest at the Sub G0 phase. α-tocopherol thus, showed potential as an antitumour agent for the treatment of oral cancer and merits further research.
    Matched MeSH terms: Oxidative Stress/drug effects
  4. Mitigation of oxidative stress damage caused by abiotic stress to improve biomass yield of microalgae: A review
    Zhu J, Cai Y, Wakisaka M, Yang Z, Yin Y, Fang W, et al.
    Sci Total Environ, 2023 Oct 20;896:165200.
    PMID: 37400020 DOI: 10.1016/j.scitotenv.2023.165200
    Microalgae have been recognized as emerging cell factories due to the high value-added bio-products. However, the balance between algal growth and the accumulation of metabolites is always the main contradiction in algal biomass production. Hence, the security and effectiveness of regulating microalgal growth and metabolism simultaneously have drawn substantial attention. Since the correspondence between microalgal growth and reactive oxygen species (ROS) level has been confirmed, improving its growth under oxidative stress and promoting biomass accumulation under non-oxidative stress by exogenous mitigators is feasible. This paper first introduced ROS generation in microalgae and described the effects of different abiotic stresses on the physiological and biochemical status of microalgae from these aspects associated with growth, cell morphology and structure, and antioxidant system. Secondly, the role of exogenous mitigators with different mechanisms in alleviating abiotic stress was concluded. Finally, the possibility of exogenous antioxidants regulating microalgal growth and improving the accumulation of specific products under non-stress conditions was discussed.
    Matched MeSH terms: Oxidative Stress
  5. Effects of edible bird's nest on hippocampal and cortical neurodegeneration in ovariectomized rats
    Zhiping H, Imam MU, Ismail M, Ismail N, Yida Z, Ideris A, et al.
    Food Funct, 2015 May;6(5):1701-11.
    PMID: 25920003 DOI: 10.1039/c5fo00226e
    The aim of this research is to investigate whether edible bird's nest (EBN) attenuates cortical and hippocampal neurodegeneration in ovariectomized rats. Ovariectomized rats were randomly divided into seven experimental groups (n = 6): the ovariectomy (OVX) group had their ovaries surgically removed; the sham group underwent surgical procedure similar to OVX group, but ovaries were left intact; estrogen group had OVX and received estrogen therapy (0.2 mg kg(-1) per day); EBN treatment groups received 6%, 3%, and 1.5% EBN, respectively. Control group was not ovariectomized. After 12 weeks of intervention, biochemical assays were performed for markers of neurodegeneration, and messenger ribonucleic acid (mRNA) levels of oxidative stress-related genes in the hippocampus and frontal cortex of the brain were analysed. Caspase 3 (cysteine-aspartic proteases 3) protein levels in the hippocampus and frontal cortex were also determined using western blotting. The results show that EBNs significantly decreased estrogen deficiency-associated serum elevation of advanced glycation end-products (AGEs), and they changed redox status as evidenced by oxidative damage (malondialdehyde content) and enzymatic antioxidant defense (superoxide dismutase and catalase) markers. Furthermore, genes associated with neurodegeneration and apoptosis were downregulated in the hippocampus and frontal cortex by EBN supplementation. Taken together, the results suggest that EBN has potential for neuroprotection against estrogen deficiency-associated senescence, at least in part via modification of the redox system and attenuation of AGEs.
    Matched MeSH terms: Oxidative Stress
  6. Fulltext Kaempferol ameliorates palmitate-induced lipid accumulation in HepG2 cells through activation of the Nrf2 signaling pathway
    Zhao L, Yang L, Ahmad K
    Hum Exp Toxicol, 2023;42:9603271221146780.
    PMID: 36607234 DOI: 10.1177/09603271221146780
    OBJECTIVES: Kaempferol (KMF), has beneficial effects against hepatic lipid accumulation. In this study, we aimed to investigate molecular mechanism underlying the protective effect of KMF on lipid accumulation.

    METHODS: HepG2 cells were treated with different concentrations of KMF and 0.5 mM palmitate (PA) for 24  h. The mRNA and protein levels of genes involved in lipid metabolism were evaluated using real-time PCR and western blot. The expression of Nrf2 was silenced using siRNA.

    RESULTS: Data indicated that KMF (20 μM) reversed PA-induced increased triglyceride (TG) levels and total lipid content. These effects were accompanied by down-regulation of the mRNA and protein levels of lipogenic genes (FAS, ACC and SREBP1), and up-regulation of genes related to fatty acid oxidation (CPT-1, HADHα and PPARα). Kaempferol significantly decreased the levels of the oxidative stress markers (ROS and MDA) and enhanced the activities of antioxidant enzymes SOD and GPx in PA-challenged cells. Luciferase analysis showed that KMF increased the transactivation of Nrf2 in hepatocytes. The results also revealed that KMF-mediated activation of Nrf2 target genes was suppressed by Nrf2 siRNA. Furthermore, Nrf2 siRNA abolished the KMF-induced reduction in ROS and MDA levels in PA treated cells. In addition, the inhibitory effect of KMF on TG levels and the mRNA and protein levels of FAS, ACC and SREPB-1 were significantly abolished by Nrf2 inhibition. Nrf2 inhibition also suppressed the KMF-induced activation of genes involved in β oxidation (CPT-1 and PPAR-α).

    CONCLUSION: The results suggest that KMF protects HepG2 cells from PA-induced lipid accumulation via activation of the Nrf2 signaling pathway.

    Matched MeSH terms: Oxidative Stress
  7. Fulltext Interleukin-6 is required for pancreatic cancer progression by promoting MAPK signaling activation and oxidative stress resistance
    Zhang Y, Yan W, Collins MA, Bednar F, Rakshit S, Zetter BR, et al.
    Cancer Res, 2013 Oct 15;73(20):6359-74.
    PMID: 24097820 DOI: 10.1158/0008-5472.CAN-13-1558-T
    Pancreatic cancer, one of the deadliest human malignancies, is almost invariably associated with the presence of an oncogenic form of Kras. Mice expressing oncogenic Kras in the pancreas recapitulate the stepwise progression of the human disease. The inflammatory cytokine interleukin (IL)-6 is often expressed by multiple cell types within the tumor microenvironment. Here, we show that IL-6 is required for the maintenance and progression of pancreatic cancer precursor lesions. In fact, the lack of IL-6 completely ablates cancer progression even in presence of oncogenic Kras. Mechanistically, we show that IL-6 synergizes with oncogenic Kras to activate the reactive oxygen species detoxification program downstream of the mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) signaling cascade. In addition, IL-6 regulates the inflammatory microenvironment of pancreatic cancer throughout its progression, providing several signals that are essential for carcinogenesis. Thus, IL-6 emerges as a key player at all stages of pancreatic carcinogenesis and a potential therapeutic target.
    Matched MeSH terms: Oxidative Stress/genetics; Oxidative Stress/physiology*
  8. Fulltext Antioxioxidant and antiapoptotic effects of Thymosin β4 in Aβ-induced SH-SY5Y cells via the 5-HTR1A/ERK axis
    Zhang GH, Chin KL, Yan SY, Pare R
    PLoS One, 2023;18(10):e0287817.
    PMID: 37788276 DOI: 10.1371/journal.pone.0287817
    Alzheimer's disease (AD) is a common amnestic cognitive impairment characterised by β-amyloid (Aβ) plaques deposit in the brain of the elderly. AD is a yet incurable disease due to its unknown exact pathogenesis and unavailability of effective remedies in clinical application. Thymosin β4 (Tβ4) is a housekeeping protein that plays important role in cell proliferation, migration and differentiation. It has the ability to protect and repair neurons however it is still unclear involvement in AD. Therefore, the aim of this study is to elucidate the role and mechanism of Tβ4 in mediating the improvement of AD. AD-like cell model was constructed in neuroblastoma cell line SH-SY5Y treated with Aβ. Overexpression of Tβ4 were done using lentivirus infection and downregulation through siRNA transfection. We performed western blot and flow cytometry to study the apoptosis and standard kits to measure the oxidative stress-associated biomarkers. There is significant increased in viability and decreased apoptosis in Tβ4 overexpression group compared to control. Furthermore, overexpression of Tβ4 suppressed the expression of pro-apoptotic markers such as Caspase-3, Caspase-8, and Bax meanwhile upregulated the expression of anti-apoptotic gene Bcl-2. Tβ4 alleviated oxidative damage by reducing MDA, LDH and ROS and increasing SOD and GSH-PX in Aβ-treated SH-SY5Y cells. We found that Tβ4 inhibit ERK/p38 MAPK pathway and intensify the expression of 5-HTR1A. Additionally, we showed that upregulation of 5-HTR1A dampened the Tβ4 to activate ERK signalling. In conclusion, our study revealed the neuroprotective role of Tβ4 in AD which may open up new therapeutic applications in AD treatment.
    Matched MeSH terms: Oxidative Stress
  9. Oxidative torrefaction performance of microalga Nannochloropsis Oceanica towards an upgraded microalgal solid biofuel
    Zhang C, Ho SH, Chen WH, Wang R, Show PL, Ong HC
    J Biotechnol, 2021 Sep 10;338:81-90.
    PMID: 34298023 DOI: 10.1016/j.jbiotec.2021.07.009
    Microalgae are a promising feedstock for carbon-neutral biofuel production due to their superior cellular composition. Alternatively, oxidative torrefaction has been recognized as a potential thermochemical technique for microalgal solid biofuel upgrading. Herein, by using microalga N. oceanica as a feedstock, several characterizations are adopted for evaluating the potential of oxidative torrefaction towards microalgal solid biofuel production. The oxidatively torrefied microalgae can be upgraded as lignite. After in-depth analysis, significant change in the surface microstructure of oxidatively torrefied microalgae is largely changed (via wrinkle and fragmentation) The hydrophobicity, thermal decomposition, thermal stability, and aromatization of oxidatively torrefied microalgae can be largely enhanced as the oxidative torrefaction severity increase. With the increasing torrefaction temperature, the hydrophobicity of oxidative torrefied microalgae gradually improved. The decomposition of C-2/3/5, and -OCH3, the CO bonds of CH3CO-, and the aromatization occurs via oxidative torrefaction according to the NMR analysis. For XPS analysis, torrefaction operation significantly decreases the carbide carbon and enhances the graphitization. As a result, the thermal stability of oxidatively torrefied microalgae is improved. Conclusively, the information obtained in this study can provide insights into the evaluation of oxidative torrefaction performance and fuel properties of microalgal solid biofuel, which may help accelerate the advancement of oxidative torrefaction industrialization.
    Matched MeSH terms: Oxidative Stress
  10. Comparative advantages analysis of oxidative torrefaction for solid biofuel production and property upgrading
    Zhang C, Chen WH, Ho SH, Zhang Y, Lim S
    Bioresour Technol, 2023 Oct;386:129531.
    PMID: 37473787 DOI: 10.1016/j.biortech.2023.129531
    This study performs the comparative advantage analysis of oxidative torrefaction of corn stalks to investigate the advantages of oxidative torrefaction for biochar fuel property upgrading. The obtained results indicate that oxidative torrefaction is more efficient in realizing mass loss and energy density improvement, as well as elemental carbon accumulation and surface functional groups removal, and thus leads to a better fuel property. The maximum values of relative mass loss, higher heating value, enhancement factor, and energy yield are 3.00, 1.10, 1.03, and 0.87, respectively. The relative elemental carbon, hydrogen, and oxygen content ranges are 1.30-3.10, 1.50-3.30, and 2.00-6.80, respectively. In addition, an excellent linear distribution is obtained between the comprehensive pyrolysis index and torrefaction severity index, with elemental carbon and oxygen component variation stemming from pyrolysis performance correlating to the elemental component and valance.
    Matched MeSH terms: Oxidative Stress
  11. Lactobacillus plantarum DR7 improved brain health in aging rats via the serotonin, inflammatory and apoptosis pathways
    Zaydi AI, Lew LC, Hor YY, Jaafar MH, Chuah LO, Yap KP, et al.
    Benef Microbes, 2020 Dec 02;11(8):753-766.
    PMID: 33245015 DOI: 10.3920/BM2019.0200
    Aging processes affect the brain in many ways, ranging from cellular to functional levels which lead to cognitive decline and increased oxidative stress. The aim of this study was to investigate the potentials of Lactobacillus plantarum DR7 on brain health including cognitive and memory functions during aging and the impacts of high fat diet during a 12-week period. Male Sprague-Dawley rats were separated into six groups: (1) young animals on normal diet (ND, (2) young animals on a high fat diet (HFD), (3) aged animals on ND, (4) aged animals on HFD, (5) aged animals on HFD and L. plantarum DR7 (109 cfu/day) and (6) aged animals receiving HFD and lovastatin. To induce ageing, all rats in group 3 to 6 were injected sub-cutaneously at 600 mg/kg/day of D-galactose daily. The administration of DR7 has reduced anxiety accompanied by enhanced memory during behavioural assessments in aged-HFD rats (P<0.05). Hippocampal concentration of all three pro-inflammatory cytokines were increased during aging but reduced upon administration of both statin and DR7. Expressions of hippocampal neurotransmitters and apoptosis genes showed reduced expressions of indoleamine dioxygenase and P53 accompanied by increased expression of TPH1 in aged- HFD rats administered with DR7, indicating potential effects of DR7 along the pathways of serotonin and oxidative senescence. This study provided an insight into potentials of L. plantarum DR7 as a prospective dietary strategy to improve cognitive functions during aging. This study provided an insight into potentials of L. plantarum DR7 as a prospective dietary strategy to improve cognitive functions during aging.
    Matched MeSH terms: Oxidative Stress
  12. Fulltext Mechanism(s) of action underlying the gastroprotective effect of ethyl acetate fraction obtained from the crude methanolic leaves extract of Muntingia calabura
    Zakaria ZA, Balan T, Azemi AK, Omar MH, Mohtarrudin N, Ahmad Z, et al.
    BMC Complement Altern Med, 2016 Feb 24;16:78.
    PMID: 26912079 DOI: 10.1186/s12906-016-1041-0
    BACKGROUND: Muntingia calabura L. (family Muntingiaceae), commonly known as Jamaican cherry or kerukup siam in Malaysia, is used traditionally to treat various ailments. The aim of this study is to elucidate the possible underlying gastroprotective mechanisms of ethyl acetate fraction (EAF) of Muntingia calabura methanolic leaves extract (MEMC).

    METHODS: MEMC and its fractions were subjected to HPLC analysis to identify and quantify the presence of its phyto-constituents. The mechanism of gastroptotection of EAF was further investigated using pylorus ligation-induced gastric lesion rat model (100, 250, and 500 mg/kg). Macroscopic analysis of the stomach, evaluation of gastric content parameters such as volume, pH, free and total acidity, protein estimation, and quantification of mucus were carried out. The participation of nitric oxide (NO) and sulfhydryl (SH) compounds was evaluated and the superoxide dismutase (SOD), gluthathione (GSH), catalase (CAT), malondialdehyde (MDA), prostaglandin E2 (PGE2) and NO level in the ethanol induced stomach tissue homogenate was determined.

    RESULTS: HPLC analysis confirmed the presence of quercetin and gallic acid in EAF. In pylorus-ligation model, EAF significantly (p <0.001) prevent gastric lesion formation. Volume of gastric content and total protein content reduced significantly (p 

    Matched MeSH terms: Oxidative Stress/drug effects
  13. Fulltext Polyphenolics and triterpenes presence in chloroform extract of Dicranopteris linearis leaves attenuated paracetamol-induced liver intoxication in rat
    Zakaria ZA, Sahmat A, Azmi AH, Nur Zainol AS, Omar MH, Balan T, et al.
    BMC Complement Med Ther, 2021 Jan 14;21(1):35.
    PMID: 33446155 DOI: 10.1186/s12906-020-03200-2
    INTRODUCTION: Water-soluble, but not lipid-soluble, extract of Dicranopteris linearis leaves has been proven to possess hepatoprotective activity. The present study aimed to validate the hepatoprotective and antioxidant activities, and phytoconstituents of lipid-soluble (chloroform) extract of D. linearis leaves.

    METHODS: The extract of D. linearis leaves (CEDL; 50, 250 and 500 mg/kg) was orally administered to rats for 7 consecutive days followed by the oral administration of 3 g/kg PCM to induce liver injury. Blood was collected for liver function analysis while the liver was obtained for histopathological examination and endogenous antioxidant activity determination. The extract was also subjected to antioxidant evaluation and phytochemicals determination via phytochemical screening, HPLC and UPLC-HRMS analyses.

    RESULTS: CEDL exerted significant (p 

    Matched MeSH terms: Oxidative Stress/drug effects
  14. Fulltext Vitamin E improved bone strength and bone minerals in male rats given alcohol
    Zakaria S, Mat-Husain SZ, Ying-Hwey K, Xin-Kai K, Mohd-Badawi A, Abd-Ghani NA, et al.
    Iran J Basic Med Sci, 2017 Dec;20(12):1360-1367.
    PMID: 29238472 DOI: 10.22038/IJBMS.2017.9610
    Objectives: Alcohol consumption induces oxidative stress on bone, which in turn increases the risk of osteoporosis. This study determined the effects of vitamin E on bone strength and bone mineral content in alcohol-induced osteoporotic rats.

    Materials and Methods: Three months old Sprague Dawley male rats were randomly divided into 5 groups: (I) control group; (II) alcohol (3g/kg) + normal saline; (III) alcohol (3g/kg) + olive oil; (IV) alcohol (3g/kg) + alpha-tocopherol (60mg/kg) and (V) alcohol (3g/kg) + palm vitamin E (60mg/kg). The treatment lasted for three months. Following sacrifice, the right tibia was subjected to bone biomechanical test while the lumbar (fourth and fifth lumbar) and left tibia bones were harvested for bone mineral measurement.

    Results: Alcohol caused reduction in bone biomechanical parameters (maximum force, ultimate stress, yield stress and Young's modulus) and bone minerals (bone calcium and magnesium) compared to control group (P<0.05). Palm vitamin E was able to improve bone biomechanical parameters by increasing the maximum force, ultimate stress and Young's modulus (P<0.05) while alpha-tocopherol was not able to. Both alpha-tocopherol and palm vitamin E were able to significantly increase tibia calcium and magnesium content while only alpha-tocopherol caused significant increase in lumbar calcium content (P<0.05).

    Conclusion: Both palm vitamin E and alpha-tocopherol improved bone mineral content which was reduced by alcohol. However, only palm vitamin E was able to improve bone strength in alcohol treated rats.

    Matched MeSH terms: Oxidative Stress
  15. Virulence, Host-Selective Toxin Production, and Development of Three Cochliobolus Phytopathogens Lacking the Sfp-Type 4'-Phosphopantetheinyl Transferase Ppt1
    Zainudin NA, Condon B, De Bruyne L, Van Poucke C, Bi Q, Li W, et al.
    Mol Plant Microbe Interact, 2015 Oct;28(10):1130-41.
    PMID: 26168137 DOI: 10.1094/MPMI-03-15-0068-R
    The Sfp-type 4'-phosphopantetheinyl transferase Ppt1 is required for activation of nonribosomal peptide synthetases, including α-aminoadipate reductase (AAR) for lysine biosynthesis and polyketide synthases, enzymes that biosynthesize peptide and polyketide secondary metabolites, respectively. Deletion of the PPT1 gene, from the maize pathogen Cochliobolus heterostrophus and the rice pathogen Cochliobolus miyabeanus, yielded strains that were significantly reduced in virulence to their hosts. In addition, ppt1 mutants of C. heterostrophus race T and Cochliobolus victoriae were unable to biosynthesize the host-selective toxins (HST) T-toxin and victorin, respectively, as judged by bioassays. Interestingly, ppt1 mutants of C. miyabeanus were shown to produce tenfold higher levels of the sesterterpene-type non-HST ophiobolin A, as compared with the wild-type strain. The ppt1 strains of all species were also reduced in tolerance to oxidative stress and iron depletion; both phenotypes are associated with inability to produce extracellular siderophores biosynthesized by the nonribosomal peptide synthetase Nps6. Colony surfaces were hydrophilic, a trait previously associated with absence of C. heterostrophus Nps4. Mutants were decreased in asexual sporulation and C. heterostrophus strains were female-sterile in sexual crosses; the latter phenotype was observed previously with mutants lacking Nps2, which produces an intracellular siderophore. As expected, mutants were albino, since they cannot produce the polyketide melanin and were auxotrophic for lysine because they lack an AAR.
    Matched MeSH terms: Oxidative Stress
  16. 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
  17. Combating oxidative stress disorders with citrus flavonoid: Naringenin
    Zaidun NH, Thent ZC, Latiff AA
    Life Sci, 2018 Sep 01;208:111-122.
    PMID: 30021118 DOI: 10.1016/j.lfs.2018.07.017
    The incidence of diseases related to oxidative stress disorders have been increased dramatically. Alternatives medicine or the active compound extracted from the natural products received great attention among researches at the present era. Naringenin (NG), a common dietary flavanone, found in the citrus fruits such as oranges, bergamots, lemons and grapefruit. It is used in the several oxidative stress disorders as the nutraceutical value of the compound emerges. Functionally, the antioxidants effect of NG is primarily attributed by reducing the free radical like reactive oxygen species (ROS) and enhancing the antioxidants activity such as superoxide dismutase (SOD), catalase, glutathione (GSH) in chronic diseases such as cardiovascular, neurodegenerative, diabetes, pulmonary, cancer and nephropathy. The present review article summarised the antioxidant property of NG and its molecular mechanism towards such diseases. Pubmed, Science Direct, Scopus, Web of Science and Google scholar were searched using the terms 'naringenin', 'oxidative stress disorders', 'naringenin and cardiovascular diseases', 'naringenin and diabetes mellitus', 'naringenin and neurodegenerative diseases', 'naringenin and pulmonary diseases', 'naringenin and cancer' and 'naringenin and nephropathy'. There has been special attention on evaluating anti-oxidative effect of NG on neurodegenerative diseases. Although some mechanisms of action remain vague, the current review highlighted the potential use of NG as a oxidative stress reliever which can be used as next prophylaxis compound in the treatment of the various oxidative stress disorders.
    Matched MeSH terms: Oxidative Stress/drug effects*
  18. Fulltext Palm vitamin E reduces locomotor dysfunction and morphological changes induced by spinal cord injury and protects against oxidative damage
    Zadeh-Ardabili PM, Rad SK, Rad SK, Khazaài H, Sanusi J, Zadeh MH
    Sci Rep, 2017 10 30;7(1):14365.
    PMID: 29085045 DOI: 10.1038/s41598-017-14765-3
    Spinal cord injury (SCI) occurs following different types of crushes. External and internal outcomes of SCI are including paralysis, cavity, and cyst formation. Effects of dietary derived antioxidants, such as palm vitamin E on central nervous system (CNS) encourage researchers to focus on the potential therapeutic benefits of antioxidant supplements. In the present study, experiments were carried out to evaluate the neuro-protective effect of the palm vitamin E on locomotor function and morphological damages induced SCI. Seventy-two male rats (Sprague-Dawley) were randomly divided into four groups: sham (laminectomy); control (supplemented with the palm vitamin E at a dose of 100 mg/kg/day); untreated-SCI (partial crush, 30-33% for 20 sec); treated-SCI (partial crush, 30-33% for 20 sec supplemented with the palm vitamin E at a dose of 100 mg/kg/day). The treatment with the palm vitamin E significantly improved the hind limb locomotor function, reduced the histopathological changes and the morphological damage in the spinal cord. Also, the palm vitamin E indicated a statistically significant decrease in the oxidative damage indicators, malondialdehyde (MDA) level and glutathione peroxidase (GPx) activity in the treated-SCI compared to the untreated-SCI.
    Matched MeSH terms: Oxidative Stress/drug effects
  19. Fulltext Antidepressant-like effects of fish, krill oils and Vit B12 against exposure to stress environment in mice models: current status and pilot study
    Zadeh-Ardabili PM, Rad SK, Rad SK, Movafagh A
    Sci Rep, 2019 Dec 27;9(1):19953.
    PMID: 31882885 DOI: 10.1038/s41598-019-56360-8
    Oxidative stress has significant role in pathophysiology of any kind of depression through actions of free radicals, non-radical molecules, and unbalancing antioxidant systems in body. In the current study, antidepressant responses of fish oil (FO), Neptune krill oil (NKO), vitamin B12 (Vit B12), and also imipramine (IMP) as the reference were studied. Natural light was employed to induce stress in the animals followed by oral administration of the drugs for 14 days. The antidepressant effect was assessed by tail suspension test (TST) and forced swimming test (FST), antioxidant enzymes and oxidative stress markers were then measured in the brain tissue of the animals. The administration of FO and NKO could significantly reduce the immobility of the animals; while, increasing climbing and swimming time compared to the normal saline in CUS-control group in TST and FST, similarly to IMP but not with Vit B12. Vit B12 could not effect on SOD activity and H2O2 level, but, cause decrease of the malondialdihydric (MDA) level and CAT activity, as well as increased the GPx and GSH activities. The rest treatments led to decrease of MDA, H2O2 levels and CAT activity and increase of GPx, SOD, GSH activities.
    Matched MeSH terms: Oxidative Stress/drug effects
  20. Effect of Antihypertensive Drug Treatment on Oxidative Stress Markers in Heart of Spontaneously Hypertensive Rat Models
    Yusoff NSN, Mustapha Z, Sharif SET, Govindasamy C, Sirajudeen KNS
    J Environ Pathol Toxicol Oncol, 2017;36(1):43-53.
    PMID: 28605330 DOI: 10.1615/JEnvironPatholToxicolOncol.2017014521
    Oxidative stress has been suggested to play a role in hypertension- and hypertension-induced organ damage. The effect of antihypertensive drug treatments on oxidative stress markers has not been well assessed. Therefore, in this study we investigated the effect of enalapril on oxidative stress markers in hearts of hypertensive rat models such as spontaneously hypertensive rats (SHR) and SHRs administered N-nitro-L-arginine methyl ester (SHR+L-NAME rats). Male rats were divided into four groups: SHRs, SHR+enalapril (SHR-E) rats, SHR+L-NAME rats, SHR+enalapril+L-NAME (SHRE+L-NAME) rats. Rats (SHREs) were administered enalapril (30 mg kg-1 day-1) in drinking water from week 4 to week 28 and L-NAME (25 mg kg-1 day-1) from week 16 to week 28 in drinking water. At the end of 28 weeks, animals were sacrificed, and their hearts were collected for the assessment of oxidative stress markers and histological examination. Enalapril treatment significantly enhanced the total antioxidant status (TAS) (P < 0.001), reduced the oxidized glutathione ratio (GSH : GSSG) (P < 0.001), and reduced to thibarbituric acid reactive substances (TBARS) (P < 0.001) and protein carbonyl content (PCO) (P < 0.001), which thus reduced the oxidative stress in the heart. The fibrosis areas in SHRs and SHR+L-NAME rats were also markedly reduced. These findings suggest that enalapril might play a protective role in hypertension- and hypertension-induced organ damage.
    Matched MeSH terms: Oxidative Stress/drug effects*
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