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  1. Wong ZW, Thanikachalam PV, Ramamurthy S
    Biomed Pharmacother, 2017 Oct;94:1145-1166.
    PMID: 28826162 DOI: 10.1016/j.biopha.2017.08.009
    Modern medicine has been used to treat myocardial infarction, a subset of cardiovascular diseases, and have been relatively effective but not without adverse effects. Consequently, this issue has stimulated interest in the use of natural products, which may be equally effective and better tolerated. Many studies have investigated the cardioprotective effect of natural products, such as plant-derived phytochemicals, against isoproterenol (ISO)-induced myocardial damage; these have produced promising results on the basis of their antioxidant, anti-atherosclerotic, anti-apoptotic and anti-inflammatory activities. This review briefly introduces the pathophysiology of myocardial infarction (MI) and then addresses the progress of natural product research towards its treatment. We highlight the promising applications and mechanisms of action of plant extracts, phytochemicals and polyherbal formulations towards the treatment of ISO-induced myocardial damage. Most of the products displayed elevated antioxidant levels with decreased oxidative stress and lipid peroxidation, along with restoration of ionic balance and lowered expression of myocardial injury markers, pro-inflammatory cytokines, and apoptotic parameters. Likewise, lipid profiles were positively altered and histopathological improvements could be seen from, for example, the better membrane integrity, decreased necrosis, edema, infarct size, and leukocyte infiltration. This review highlights promising results towards the amelioration of ISO-induced myocardial damage, which suggest the direction for future research on natural products that could be used to treat MI.
    Matched MeSH terms: Oxidative Stress/drug effects
  2. Ooi BK, Goh BH, Yap WH
    Int J Mol Sci, 2017 Nov 05;18(11).
    PMID: 29113088 DOI: 10.3390/ijms18112336
    Oxidative stress is an important risk factor contributing to the pathogenesis of cardiovascular diseases. Oxidative stress that results from excessive reactive oxygen species (ROS) production accounts for impaired endothelial function, a process which promotes atherosclerotic lesion or fatty streaks formation (foam cells). Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcription factor involved in cellular redox homeostasis. Upon exposure to oxidative stress, Nrf2 is dissociated from its inhibitor Keap-1 and translocated into the nucleus, where it results in the transcriptional activation of cell defense genes. Nrf2 has been demonstrated to be involved in the protection against foam cells formation by regulating the expression of antioxidant proteins (HO-1, Prxs, and GPx1), ATP-binding cassette (ABC) efflux transporters (ABCA1 and ABCG1) and scavenger receptors (scavenger receptor class B (CD36), scavenger receptor class A (SR-A) and lectin-type oxidized LDL receptor (LOX-1)). However, Nrf2 has also been reported to exhibit pro-atherogenic effects. A better understanding on the mechanism of Nrf2 in oxidative stress-induced cardiac injury, as well as the regulation of cholesterol uptake and efflux, are required before it can serve as a novel therapeutic target for cardiovascular diseases prevention and treatment.
    Matched MeSH terms: Oxidative Stress*
  3. Hamirah NK, Kamsani YS, Mohamed Nor Khan NA, Ab Rahim S, Rajikin MH
    Med Sci Monit Basic Res, 2017 Dec 08;23:373-379.
    PMID: 29217815
    BACKGROUND Cytoskeletal structures, in particular actin and tubulin, provide a fundamental framework in all cells, including embryos. The objective of this study was to evaluate the effects of nicotine, which is a source of oxidative stress, and subsequent supplementation with Tocotrienol-rich fraction (TRF) on actin and tubulin of 2- and 8-cell murine embryos. MATERIAL AND METHODS Thirty female Balb/C mice were divided into 4 groups: Group 1 received: subcutaneous (sc) injection of 0.9% NaCl; Group 2 received sc injection of 3.0 nicotine mg/kg bw/day; Group 3 received 3.0 sc injection of nicotine mg/kg bw/day +60 mg/kg bw/day TRF; and Group 4 received 60 sc injection of TRF mg/kg bw/day for 7 consecutive days. The animals were superovulated with 5 IU PMSG followed by 5 IU hCG 48 h later. Animals were cohabited with fertile males overnight and euthanized through cervical dislocation at 24 h post coitum. Embryos at the 2- and 8-cell stages were harvested, fixed, and stained to visualize actin and tubulin distributions by using CLSM. RESULTS Results showed that at 2-cell stage, actin intensities were significantly reduced in the nicotine group compared to that of the control group (p<0.001). In Group 3, the intensity of actin significantly increased compared to that of the nicotine group (p<0.001). At 8-cell stage, actin intensity of the nicotine group was significantly lower than that of the control group (p<0.001). The intensities of actin in Group 3 were increased compared to that of nicotine treatment alone (p<0.001). The same trend was seen in tubulin at 2- and 8-cell stages. Interestingly, both actin and tubulin structures in the TRF-treated groups were enhanced compared to the control. CONCLUSIONS This study suggests that TRF prevents the deleterious effects of nicotine on the cytoskeletal structures of 2- and 8-cell stages of pre-implantation mice embryos in vitro.
    Matched MeSH terms: Oxidative Stress/drug effects
  4. Ghassem M, Arihara K, Mohammadi S, Sani NA, Babji AS
    Food Funct, 2017 May 24;8(5):2046-2052.
    PMID: 28497137 DOI: 10.1039/c6fo01615d
    Edible bird's nest (EBN) is widely consumed as a delicacy and traditional medicine amongst the Chinese. In the present study, for the first time, the antioxidant properties of an EBN pepsin-trypsin hydrolysate of the swiftlet species Aerodramus fuciphagus and its ultrafiltration fractions were investigated. Thirteen peptides with molecular weights between 514.29 and 954.52 Da were identified in the EBN fraction with the use of mass spectrometry. Two novel pentapeptides Pro-Phe-His-Pro-Tyr and Leu-Leu-Gly-Asp-Pro, corresponding to f134-138 and f164-168 of cytochrome b of A. fuciphagus, indicated the highest ORAC values of 14.95 and 14.32 μM of TE μM(-1) peptide, respectively. Both purified peptides showed resistance against simulated gastrointestinal proteases. In addition, both peptides had no in vitro cytotoxicity on human lung MRC-5 cells and prevented human liver carcinoma HepG2 cellular damage caused by hydroxyl radicals. Therefore, it is suggested that EBN protein hydrolysates are a good source of natural antioxidants and could be applied as nutraceutical compounds.
    Matched MeSH terms: Oxidative Stress/drug effects
  5. Puthucheary SD, Nathan SA
    Singapore Med J, 2008 Feb;49(2):117-20.
    PMID: 18301838
    Oxidative stress can occur in sepsis and infection, when overproduction of free radicals is not countered by the host antioxidant system, leading to impairment of host cellular functions. Various disease states are accompanied by the accumulation of 15-F2t-IsoP in biological fluids. These isoprostanes are considered as markers of oxidative stress, and inflammation and inflammatory mediators.
    Matched MeSH terms: Oxidative Stress/physiology
  6. Balkrishna A, Kumar A, Arya V, Rohela A, Verma R, Nepovimova E, et al.
    Oxid Med Cell Longev, 2021;2021:3155962.
    PMID: 34737844 DOI: 10.1155/2021/3155962
    Nanotechnology is gaining significant attention, with numerous biomedical applications. Silver in wound dressings, copper oxide and silver in antibacterial preparations, and zinc oxide nanoparticles as a food and cosmetic ingredient are common examples. However, adverse effects of nanoparticles in humans and the environment from extended exposure at varied concentrations have yet to be established. One of the drawbacks of employing nanoparticles is their tendency to cause oxidative stress, a significant public health concern with life-threatening consequences. Cardiovascular, renal, and respiratory problems and diabetes are among the oxidative stress-related disorders. In this context, phytoantioxidant functionalized nanoparticles could be a novel and effective alternative. In addition to performing their intended function, they can protect against oxidative damage. This review was designed by searching through various websites, books, and articles found in PubMed, Science Direct, and Google Scholar. To begin with, oxidative stress, its related diseases, and the mechanistic basis of oxidative damage caused by nanoparticles are discussed. One of the main mechanisms of action of nanoparticles was unearthed to be oxidative stress, which limits their use in humans. Secondly, the role of phytoantioxidant functionalized nanoparticles in oxidative damage prevention is critically discussed. The parameters for the characterization of nanoparticles were also discussed. The majority of silver, gold, iron, zinc oxide, and copper nanoparticles produced utilizing various plant extracts were active free radical scavengers. This potential is linked to several surface fabricated phytoconstituents, such as flavonoids and phenols. These phytoantioxidant functionalized nanoparticles could be a better alternative to nanoparticles prepared by other existing approaches.
    Matched MeSH terms: Oxidative Stress/drug effects*
  7. Sapian S, Taib IS, Latip J, Katas H, Chin KY, Mohd Nor NA, et al.
    Int J Mol Sci, 2021 Oct 27;22(21).
    PMID: 34769045 DOI: 10.3390/ijms222111616
    Diabetes cardiomyopathy is one of the key factors of mortality among diabetic patients around the globe. One of the prior contributors to the progression of diabetic cardiomyopathy is cardiac mitochondrial dysfunction. The cardiac mitochondrial dysfunction can induce oxidative stress in cardiomyocytes and was found to be the cause of majority of the heart morphological and dynamical changes in diabetic cardiomyopathy. To slow down the occurrence of diabetic cardiomyopathy, it is crucial to discover therapeutic agents that target mitochondrial-induced oxidative stress. Flavonoid is a plentiful phytochemical in plants that shows a wide range of biological actions against human diseases. Flavonoids have been extensively documented for their ability to protect the heart from diabetic cardiomyopathy. Flavonoids' ability to alleviate diabetic cardiomyopathy is primarily attributed to their antioxidant properties. In this review, we present the mechanisms involved in flavonoid therapies in ameliorating mitochondrial-induced oxidative stress in diabetic cardiomyopathy.
    Matched MeSH terms: Oxidative Stress/drug effects*
  8. Taib IS, Budin SB, Ghazali AR, Jayusman PA, Louis SR, Mohamed J
    Clinics (Sao Paulo), 2013 Jan;68(1):93-100.
    PMID: 23420164
    OBJECTIVE: Fenitrothion residue is found primarily in soil, water and food products and can lead to a variety of toxic effects on the immune, hepatobiliary and hematological systems. However, the effects of fenitrothion on the male reproductive system remain unclear. This study aimed to evaluate the effects of fenitrothion on the sperm and testes of male Sprague-Dawley rats.

    METHODS: A 20 mg/kg dose of fenitrothion was administered orally by gavages for 28 consecutive days. Blood sample was obtained by cardiac puncture and dissection of the testes and cauda epididymis was performed to obtain sperm. The effects of fenitrothion on the body and organ weight, biochemical and oxidative stress, sperm characteristics, histology and ultrastructural changes in the testes were evaluated.

    RESULTS: Fenitrothion significantly decreased the body weight gain and weight of the epididymis compared with the control group. Fenitrothion also decreased plasma cholinesterase activity compared with the control group. Fenitrothion altered the sperm characteristics, such as sperm concentration, sperm viability and normal sperm morphology, compared with the control group. Oxidative stress markers, such as malondialdehyde, protein carbonyl, total glutathione and glutathione S-transferase, were significantly increased and superoxide dismutase activity was significantly decreased in the fenitrothion-treated group compared with the control group. The histopathological and ultrastructural examination of the testes of the fenitrothion-treated group revealed alterations corresponding with the biochemical changes compared with the control group.

    CONCLUSION: A 20 mg/kg dose of fenitrothion caused deleterious effects on the sperm and testes of Sprague-Dawley rats.

    Matched MeSH terms: Oxidative Stress/drug effects*
  9. Bhat S, Rao G, Murthy KD, Bhat PG
    Indian J Exp Biol, 2007 May;45(5):455-8.
    PMID: 17569288
    The present study was aimed to find out whether a change in the alignment of the pyramid from the north-south axis causes any variation in the effects produced by it on plasma cortisol levels and markers of oxidative stress in erythrocytes of adult-female Wistar rats. Plasma cortisol and erythrocyte TBARS levels were significantly lower whereas erythrocyte GSH was significantly higher in rats kept in pyramid that was aligned on the four cardinal points--north, east, south and west, as compared to normal control rats. Although there was a significant difference in the plasma cortisol level between normal control group and the group of rats kept in randomly aligned pyramid, there was no significant difference between these two groups for the other parameters. Erythrocyte TBARS levels in the group of rats kept in the randomly aligned pyramid was significantly higher than that in the group kept in the magnetically aligned pyramid. The results suggest that the north-south alignment of the pyramid is crucial for its expected effects.
    Matched MeSH terms: Oxidative Stress/physiology
  10. Khalid MF, Hussain S, Anjum MA, Morillon R, Ahmad S, Ejaz S, et al.
    PLoS One, 2021;16(4):e0247558.
    PMID: 33831006 DOI: 10.1371/journal.pone.0247558
    Water shortage is among the major abiotic stresses that restrict growth and productivity of citrus. The existing literature indicates that tetraploid rootstocks had better water-deficit tolerance than corresponding diploids. However, the associated tolerance mechanisms such as antioxidant defence and nutrient uptake are less explored. Therefore, we evaluated physiological and biochemical responses (antioxidant defence, osmotic adjustments and nutrient uptake) of diploid (2x) and tetraploid (4x) volkamer lemon (VM) rootstocks grafted with kinnow mandarin (KM) under two water-deficit regimes. The KM/4xVM (VM4) and KM/2xVM (VM2) observed decrease in photosynthetic variables, i.e., photosynthetic rate (Pn), stomatal conductance (gs), transpiration rate (E), leaf greenness (SPAD), dark adopted chlorophyll fluorescence (Fv/Fm), dark adopted chlorophyll fluorescence (Fv´/Fm´), relative water contents (RWC) and leaf surface area (LSA), and increase in non-photochemical quenching (NPQ) under both water-deficit regimes. Moreover, oxidative stress indicators, i.e., malondialdehyde (MDA) and hydrogen peroxide, and activities of antioxidant enzymes, i.e., superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APx), glutathione reductase (GR) were increased under both water-deficit regimes. Nonetheless, increase was noted in osmoprotectants such as proline (PRO) and glycine betaine (GB) and other biochemical compounds, including antioxidant capacity (AC), total phenolic content (TPC) and total soluble protein (TSP) in VM2 and VM4 under both water-deficit regimes. Dry biomass (DB) of both rootstocks was decreased under each water-deficit condition. Interestingly, VM4 showed higher and significant increase in antioxidant enzymes, osmoprotectants and other biochemical compounds, while VM2 exhibited higher values for oxidative stress indicators. Overall, results indicated that VM4 better tolerated water-deficit stress by maintaining photosynthetic variables associated with strong antioxidant defence machinery as compared to VM2. However, nutrient uptake was not differed among tested water-deficit conditions and rootstocks. The results conclude that VM4 can better tolerate water-deficit than VM2. Therefore, VM4 can be used as rootstock in areas of high-water deficiency for better citrus productivity.
    Matched MeSH terms: Oxidative Stress*
  11. Abdulwanis Mohamed Z, Mohamed Eliaser E, Jaafaru MS, Nordin N, Ioannides C, Abdull Razis AF
    Molecules, 2020 Aug 15;25(16).
    PMID: 32824120 DOI: 10.3390/molecules25163724
    Neurodegenerative diseases (NDDs) are chronic conditions that have drawn robust interest from the scientific community. Phytotherapeutic agents are becoming an important source of chemicals for the treatment and management of NDDs. Various secondary metabolites have been isolated from Melicope lunu-ankenda plant leaves, including phenolic acid derivatives. However, their neuroprotective activity remains unclear. Thus, the aim of this study is to elucidate the in vitro neuroprotective activity of 7-geranyloxycinnamic acid isolated from Melicope lunu-ankenda leaves. The neuroprotective activity was evaluated in differentiated human neuroblastoma (SH-SY5Y) cells by monitoring cell viability using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Moreover, the potential to impair apoptosis in differentiated cells was investigated employing the Annexin V-FITC assay, acridine orange and propidium iodide (AO/PI) staining, and fluorescence microscopy. Morphological assessment and ultrastructural analysis were performed using scanning and transmission electron microscopy to evaluate the effect of 7-geranyloxycinnamic acid on surface morphology and internal features of the differentiated cells. Pre-treatment of neuronal cells with 7-geranyloxycinnamic acid significantly protected the differentiated SH-SY5Y cells against H2O2-induced apoptosis. Cytoskeleton and cytoplasmic inclusion were similarly protected by the 7-geranyloxycinnamic acid treatment. The present findings demonstrate the neuroprotective potential of 7-geranyloxycinnamic acid against H2O2-induced neurotoxicity in neuronal cells, which is an established hallmark of neuronal disorders.
    Matched MeSH terms: Oxidative Stress/drug effects
  12. Swamy M, Salleh MJ, Sirajudeen KN, Yusof WR, Chandran G
    Int J Med Sci, 2010 May 31;7(3):147-54.
    PMID: 20567615
    Nitric oxide is postulated to be involved in the pathophysiology of neurological disorders due to hypoxia/ anoxia in brain due to increased release of glutamate and activation of N-methyl-D-aspartate receptors. Reactive oxygen species have been implicated in pathophysiology of many neurological disorders and in brain function. To understand their role in anoxia (hypobaric hypoxia) and reperfusion (reoxygenation), the nitric oxide synthase, argininosuccinate synthetase, argininosuccinate lyase, glutamine synthetase and arginase activities along with the concentration of nitrate /nitrite, thiobarbituric acid reactive substances and total antioxidant status were estimated in cerebral cortex, cerebellum and brain stem of rats subjected to anoxia and reperfusion. The results of this study clearly demonstrated the increased production of nitric oxide by increased activity of nitric oxide synthase. The increased activities of argininosuccinate synthetase and argininosuccinate lyase suggest the increased and effective recycling of citrulline to arginine in anoxia, making nitric oxide production more effective and contributing to its toxic effects. The decreased activity of glutamine synthetase may favor the prolonged availability of glutamic acid causing excitotoxicity leading to neuronal damage in anoxia. The increased formation of thiobarbituric acid reactive substances and decreased total antioxidant status indicate the presence of oxidative stress in anoxia and reperfusion. The increased arginase and sustained decrease of GS activity in reperfusion group likely to be protective.
    Matched MeSH terms: Oxidative Stress/physiology*
  13. Yida Z, Imam MU, Ismail M, Hou Z, Abdullah MA, Ideris A, et al.
    PMID: 26341858 DOI: 10.1186/s12906-015-0843-9
    Edible Bird's nest (EBN) is an antioxidant-rich supplement that is popular in many parts of Asia. Its antioxidant and anti-inflammatory properties have been reported using in vitro system. This paper aimed to determine the antioxidant and anti-inflammatory effects of EBN in in high fat diet induced rats model.
    Matched MeSH terms: Oxidative Stress/drug effects*
  14. Safi SZ, Qvist R, Yan GO, Ismail IS
    BMC Med Genomics, 2014;7:29.
    PMID: 24885710 DOI: 10.1186/1755-8794-7-29
    Aberrant epigenetic profiles are concomitant with a spectrum of developmental defects and diseases. Role of methylation is an increasingly accepted factor in the pathophysiology of diabetes and its associated complications. This study aims to examine the correlation between oxidative stress and methylation of β1, β2 and β3-adrenergic receptors and to analyze the differential variability in the expression of these genes under hyperglycemic conditions.
    Matched MeSH terms: Oxidative Stress/drug effects; Oxidative Stress/genetics*
  15. Rajah T, Chow SC
    Toxicol Appl Pharmacol, 2014 Jul 15;278(2):100-6.
    PMID: 24768707 DOI: 10.1016/j.taap.2014.04.014
    The caspase inhibitor benzyloxycarbony (Cbz)-l-Val-Ala-Asp (OMe)-fluoromethylketone (z-VAD-FMK) has recently been shown to inhibit T cell proliferation without blocking caspase-8 and caspase-3 activation in primary T cells. We showed in this study that z-VAD-FMK treatment leads to a decrease in intracellular glutathione (GSH) with a concomitant increase in reactive oxygen species (ROS) levels in activated T cells. The inhibition of anti-CD3-mediated T cell proliferation induced by z-VAD-FMK was abolished by the presence of low molecular weight thiols such as GSH, N-acetylcysteine (NAC) and l-cysteine, whereas d-cysteine which cannot be metabolised to GSH has no effect. These results suggest that the depletion of intracellular GSH is the underlying cause of z-VAD-FMK-mediated inhibition of T cell activation and proliferation. The presence of exogenous GSH also attenuated the inhibition of anti-CD3-induced CD25 and CD69 expression mediated by z-VAD-FMK. However, none of the low molecular weight thiols were able to restore the caspase-inhibitory properties of z-VAD-FMK in activated T cells where caspase-8 and caspase-3 remain activated and processed into their respective subunits in the presence of the caspase inhibitor. This suggests that the inhibition of T cell proliferation can be uncoupled from the caspase-inhibitory properties of z-VAD-FMK. Taken together, the immunosuppressive effects in primary T cells mediated by z-VAD-FMK are due to oxidative stress via the depletion of GSH.
    Matched MeSH terms: Oxidative Stress/drug effects*; Oxidative Stress/immunology
  16. Hussin M, Hamid AA, Mohamad S, Saari N, Bakar F, Dek SP
    J Food Sci, 2009 Mar;74(2):H72-8.
    PMID: 19323754 DOI: 10.1111/j.1750-3841.2009.01045.x
    A study was carried out to investigate the effects of Centella asiatica leaf on lipid metabolism of oxidative stress rats. The rats were fed 0.1% hydrogen peroxide (H(2)O(2)) with either 0.3% (w/w) C. asiatica extract, 5%C. asiatica powder (w/w), or 0.3% (w/w) alpha-tocopherol for 25 wk. Results of the study showed that C. asiatica powder significantly (P < 0.05) lowered serum low-density lipoprotein compared to that of control rats (rats fed H(2)O(2) only). At the end of the study C. asiatica-fed rats were also found to have significantly (P < 0.05) higher high-density lipoprotein and lower triglyceride level compared to rats fed only normal diet. However, cholesterol level of rats fed both C. asiatica extract and powder was found to be significantly (P < 0.05) higher compared to that of control rats. It was interesting to note that consumption of C. asiatica significantly decreased body and liver weights of the rats. Histological examinations revealed no obvious changes in all rats studied. Quantitative analysis of C. asiatica leaf revealed high concentration of total phenolic compounds, in particular, catechin, quercetin, and rutin.
    Matched MeSH terms: Oxidative Stress/drug effects; Oxidative Stress/physiology*
  17. Garg M, Khanna D, Kalra S, Balakumar P
    Fundam Clin Pharmacol, 2016 Oct;30(5):394-405.
    PMID: 27148865 DOI: 10.1111/fcp.12204
    Fenofibrate and rosuvastatin at low doses might have experimental pleiotropic benefits. This study investigated the combined effect of low doses of fenofibrate and rosuvastatin in isoproterenol-induced experimental myocardial infarction. Rats administered isoproterenol (85 mg/kg/day, s.c.) for 2 days (day 29 and day 30) of 30 days experimental protocol developed significant myocardial infarction that was accompanied with high myocardial oxidative stress and lipid peroxidation, elevated serum markers of cardiac injury, lipid abnormalities, and elevated circulatory levels of C-reactive protein. Pretreatment with low doses of fenofibrate (30 mg/kg/day p.o., 30 days) and rosuvastatin (2 mg/kg/day p.o., 30 days) both alone or in combination markedly prevented isoproterenol-induced myocardial infarction and associated abnormalities while the low-dose combination of fenofibrate and rosuvastatin was more effective. Histopathological study in isoproterenol control rat heart showed necrosis with edema and acute inflammation at the margins of necrotic area. The rat heart from low-dose fenofibrate and rosuvastatin pretreated group showed scanty inflammation and no ischemia. In conclusion, fenofibrate and rosuvastatin pretreatment in low doses might have a therapeutic potential to prevent the pathogenesis of myocardial infarction. Moreover, their combined treatment option might offer superior therapeutic benefits via a marked reduction in myocardial infarct size and oxidative stress, suggesting a possibility of their pleiotropic cardioprotective action at low doses.
    Matched MeSH terms: Oxidative Stress/drug effects; Oxidative Stress/physiology
  18. Loh WM, Ling WC, Murugan DD, Lau YS, Achike FI, Vanhoutte PM, et al.
    Vascul. Pharmacol., 2015 Aug;71:151-8.
    PMID: 25869508 DOI: 10.1016/j.vph.2015.03.011
    Des-aspartate angiotensin I (DAA-I), an endogenous nonapeptide, counteracts several effects of angiotensin II on vascular tone. The aim of this study was to investigate the acute protective effect of DAA-I on endothelial function in the spontaneously hypertensive rat (SHR) as well as its effect on angiotensin II-induced contractions and oxidative stress. Aortic rings were incubated with DAA-I (0.1μM) for 30min prior to the assessment of angiotensin II-induced contractions (0.1nM-10μM) in WKY and SHR aortas. Total nitrate and nitrite levels were assessed using a colorimetric method and reactive oxygen species (ROS) were measured by dihydroethidium (DHE) fluorescence and lucigenin-enhanced chemiluminescence. The effect of DAA-I was also assessed against endothelium-dependent and -independent relaxations to acetylcholine and sodium nitroprusside, respectively. Angiotensin II-induced contractions were significantly reduced by DAA-I, losartan and tempol. Incubation with ODQ (soluble guanylyl cyclase inhibitor) and removal of the endothelium prevented the reduction of angiotensin II-induced contractions by DAA-I. Total nitrate and nitrite levels were increased in DAA-I, losartan and tempol treated-SHR tissues while ROS level was reduced by DAA-I and the latter inhibitors. In addition, DAA-I significantly improved the impaired acetylcholine-induced relaxation in SHR aortas whilst sodium nitroprusside-induced endothelium-independent relaxation remained unaffected. The present findings indicate that improvement of endothelial function by DAA-I in the SHR aorta is mediated through endothelium-dependent release of nitric oxide and inhibition of angiotensin II-induced oxidative stress.
    Matched MeSH terms: Oxidative Stress/drug effects*; Oxidative Stress/physiology
  19. Eleazu C, Ekeleme CE, Famurewa A, Mohamed M, Akunna G, David E, et al.
    PMID: 30659555 DOI: 10.2174/1871530319666190119101058
    BACKGROUND: Research studies that holistically investigated the effect of administration of Virgin Coconut Oil (VCO) on diabetic humans or animals are limited in literature.

    OBJECTIVE: To investigate the effect of administration of VCO on lipid profile, markers of hepatic and renal dysfunction, and hepatic and renal antioxidant activities of alloxan induced diabetic rats.

    METHODS: Twenty-four male albino rats were used, and they were divided into four groups of six rats each. Group 1 (Normal Control, NC) received distilled water (1 mL/kg); Group 2 (VCO Control) received VCO (5 mL/kg); Group 3 (Diabetic Control, DC) received distilled water (1 mL/kg); Group 4 (Test Group, TG) received 5 ml/kg of VCO.

    RESULTS: There were no significant differences in blood glucose, body weights, relative liver weights, relative kidney weights, hepatic and renal Superoxide Dismutase (SOD) activities, Malondialdehyde (MDA), albumin, aspartate Amino Transaminase (AST), alanine Amino Transaminase (ALT), Alkaline Phosphatase (ALP), urea, creatinine, uric acid, total cholesterol, triacylglycerol, Very Low Density Lipoprotein cholesterol (VLDL) and Low Density Lipoprotein cholesterol (LDL) concentrations; significant increases in renal Glutathione (GSH), hepatic catalase, Glutathione Peroxidase (GPx) and GSH but significant reduction in renal GPx and catalase activities of VCO control group compared with NC group. There were significant increases in blood glucose, relative liver and kidney weights, hepatic GPx, hepatic and renal MDA concentration, ALP, AST, ALT, urea, creatinine, uric acid, triacylglycerol, total cholesterol, LDL and VLDL concentrations; and significant decreases in body weight, hepatic SOD and GSH activities and albumin concentration but no significant difference in hepatic catalase activity of DC group compared with NC group. Administration of VCO to diabetic rats positively modulated these parameters compared with the diabetic control.

    CONCLUSION: The study showed the potentials of VCO in the management of hyperlipidemia, renal and hepatic dysfunctions imposed by hyperglycemia and by oxidative stress in diabetic rats.

    Matched MeSH terms: Oxidative Stress/drug effects; Oxidative Stress/physiology
  20. Lau YS, Tian XY, Huang Y, Murugan D, Achike FI, Mustafa MR
    Biochem Pharmacol, 2013 Feb 1;85(3):367-75.
    PMID: 23178655 DOI: 10.1016/j.bcp.2012.11.010
    Increased oxidative stress is involved in the pathogenesis and progression of diabetes. Antioxidants are therapeutically beneficial for oxidative stress-associated diseases. Boldine ([s]-2,9-dihydroxy-1,10-dimethoxyaporphine) is a major alkaloid present in the leaves and bark of the boldo tree (Peumus boldus Molina), with known an antioxidant activity. This study examined the protective effects of boldine against high glucose-induced oxidative stress in rat aortic endothelial cells (RAEC) and its mechanisms of vasoprotection related to diabetic endothelial dysfunction. In RAEC exposed to high glucose (30 mM) for 48 h, pre-treatment with boldine reduced the elevated ROS and nitrotyrosine formation, and preserved nitric oxide (NO) production. Pre-incubation with β-NAPDH reduced the acetylcholine-induced endothelium-dependent relaxation; this attenuation was reversed by boldine. Compared with control, endothelium-dependent relaxation in the aortas of streptozotocin (STZ)-treated diabetic rats was significantly improved by both acute (1 μM, 30 min) and chronic (20mg/kg/daily, i.p., 7 days) treatment with boldine. Intracellular superoxide and peroxynitrite formation measured by DHE fluorescence or chemiluminescence assay were higher in sections of aortic rings from diabetic rats compared with control. Chronic boldine treatment normalized ROS over-production in the diabetic group and this correlated with reduction of NAD(P)H oxidase subunits, NOX2 and p47(phox). The present study shows that boldine reversed the increased ROS formation in high glucose-treated endothelial cells and restored endothelial function in STZ-induced diabetes by inhibiting oxidative stress and thus increasing NO bioavailability.
    Matched MeSH terms: Oxidative Stress/drug effects*; Oxidative Stress/physiology
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