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Fulltext Communal microaerophilic-aerobic biodegradation of Amaranth by novel NAR-2 bacterial consortium

Chan GF, Rashid NA, Chua LS, Ab llah N, Nasiri R, Ikubar MR

Bioresour Technol, 2012 Feb;105:48-59.
PMID: 22182471 DOI: 10.1016/j.biortech.2011.11.094

A novel bacterial consortium, NAR-2 which consists of Citrobacter freundii A1, Enterococcus casseliflavus C1 and Enterobacter cloacae L17 was investigated for biodegradation of Amaranth azo dye under sequential microaerophilic-aerobic condition. The NAR-2 bacterial consortium with E. casseliflavus C1 as the dominant strain enhanced the decolorization process resulting in reduction of Amaranth in 30 min. Further aerobic biodegradation, which was dominated by C. freundii A1 and E. cloacae L17, allowed biotransformation of azo reduction intermediates and mineralization via metabolic pathways including benzoyl-CoA, protocatechuate, salicylate, gentisate, catechol and cinnamic acid. The presence of autoxidation products which could be metabolized to 2-oxopentenoate was elucidated. The biodegradation mechanism of Amaranth by NAR-2 bacterial consortium was predicted to follow the steps of azo reduction, deamination, desulfonation and aromatic ring cleavage. This is for the first time the comprehensive microaerophilic-aerobic biotransformation pathways of Amaranth dye intermediates by bacterial consortium are being proposed.

Matched MeSH terms: Oxygen/chemistry
Phenylpropanoids isolated from Piper sarmentosum Roxb. induce apoptosis in breast cancer cells through reactive oxygen species and mitochondrial-dependent pathways

Hematpoor A, Paydar M, Liew SY, Sivasothy Y, Mohebali N, Looi CY, et al.

Chem Biol Interact, 2018 Jan 05;279:210-218.
PMID: 29174417 DOI: 10.1016/j.cbi.2017.11.014

The aim of the present study is to isolate bioactive compounds from the roots of Piper sarmentosum and examine the mechanism of action using human breast cancer cell line (MDA-MB-231). Bioassay guided-fractionation of methanolic extract led to the isolation of asaricin (1) and isoasarone (2). Asaricin (1) and isoasarone (2) had significant cytotoxicity towards MDA-MB-231. MCF-10A (human normal breast epithelial cells) cells are less sensitive than MDA-MB-231, but they respond to the treatment with the same unit of measurement. Both compounds increase reactive oxygen species (ROS), decrease mitochondrial membrane potential (MMP) and enhance cytochrome c release in treated MDA-MB-231 cells. Isoasarone (2) markedly elevated caspase -8 and -3/7 activities and caused a decline in nuclear NF-κB translocation, suggesting extrinsic, death receptor-linked apoptosis pathway. Quantitative PCR results of MDA-MB-231 treated with asaricin (1) and isoasarone (2) showed altered expression of Bcl-2: Bax level. The inhibitory potency of these isolates may support the therapeutic uses of these compounds in breast cancer.

Matched MeSH terms: Reactive Oxygen Species/metabolism*
Chemical evaluation and cytotoxic mechanism investigation of Clinacanthus nutans extract in lymphoma SUP-T1 cells

Lu MC, Li TY, Hsieh YC, Hsieh PC, Chu YL

Environ Toxicol, 2018 Dec;33(12):1229-1236.
PMID: 30188005 DOI: 10.1002/tox.22629

Clinacanthus nutans has been used as herbal medicine with antidiabetic, blood pressure lowering, and diuretic properties in Singapore, Thailand, and Malaysia. The in vitro cellular study showed the chloroform extract possessed significant cytotoxicity against leukemia K562 and lymphoma Raji cells. The clinical study reported that administration of plant could treat or prevent relapse in 12 cancer patients. However, detailed mechanism of the anticancer effects and chemical profiles are not thoroughly studied. The chemical study did show that the acetone extract (MHA) exerted the highest antiproliferative effect on human leukemia MOLT-4 cells and lymphoma SUP-T1 cells in dose-dependent cytotoxicity. We found that the use of MHA increased apoptosis by 4.28%-43.65% and caused disruption of mitochondrial membrane potential (MMP) by 11.79%-26.93%, increased reactive oxygen species (ROS) by 19.54% and increased calcium ion by 233.83%, as demonstrated by annexin-V/PI, JC-1, H2 DCFDA, and Flou-3 staining assays, respectively. MHA-induced ER stress was confirmed by increase expression of CHOP and IRE-1α with western blotting assay. In conclusion, we identified good bioactivity in Clinacanthus nutans and recognize its potential effect on cancer therapy, but further research is needed to determine the use of the plant.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Peroxiredoxin of Arthrospira platensis derived short molecule YT12 influences antioxidant and anticancer activity

Sannasimuthu A, Ramani M, Pasupuleti M, Saraswathi NT, Arasu MV, Al-Dhabi NA, et al.

Cell Biol Int, 2020 Nov;44(11):2231-2242.
PMID: 32716104 DOI: 10.1002/cbin.11431

This study demonstrates both the antioxidant and anticancer potential of the novel short molecule YT12 derived from peroxiredoxin (Prx) of spirulina, Arthrospira platensis (Ap). ApPrx showed significant reduction in reactive oxygen species (ROS) against hydrogen peroxide (H2 O2 ) stress. The complementary DNA sequence of ApPrx contained 706 nucleotides and its coding region possessed 546 nucleotides between position 115 and 660. Real-time quantitative reverse transcription polymerase chain reaction analysis confirmed the messenger RNA expression of ApPrx due to H2 O2 exposure in spirulina cells at regular intervals, in which the highest expression was noticed on Day 20. Cytotoxicity assay was performed using human peripheral blood mononuclear cells, and revealed that at 10 μM, the YT12 did not exhibit any notable toxicity. Furthermore, ROS scavenging activity of YT12 was performed using DCF-DA assay, in which YT12 scavenged a significant amount of ROS at 25 μM in H2 O2 -treated blood leukocytes. The intracellular ROS in human colon adenocarcinoma cells (HT-29) was regulated by oxidative stress, where the YT12 scavenges ROS in HT-29 cells at 12.5 μM. Findings show that YT12 peptide has anticancer activity, when treated against HT-29 cells. Through the MTT assay, YT12 showed vital cytotoxicity against HT-29 cells. These finding suggested that YT12 is a potent antioxidant molecule which defends ROS against oxidative stress and plays a role in redox balance.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Operational factors affecting the bioregeneration of mono-amine modified silica loaded with Acid Orange 7

Al-Amrani WA, Lim PE, Seng CE, Ngah WS

Water Res, 2012 Dec 1;46(19):6419-29.
PMID: 23062787 DOI: 10.1016/j.watres.2012.09.014

In this study, the operational factors affecting the bioregeneration of AO7-loaded MAMS particles in batch system, namely redox condition, initial acclimated biomass concentration, shaking speed and type of acclimated biomass were investigated. The results revealed that with the use of mixed culture acclimated to AO7 under anoxic/aerobic conditions, enhancement of the bioregeneration efficiency of AO7-loaded MAMS and the total removal efficiency of COD could be achieved when the bio-decolorization and bio-mineralization stages were fully aerated with dissolved oxygen above 7 mg/L. Shorter duration of bioregeneration was achieved by using relatively higher initial biomass concentration and lower shaking speed, respectively, whereas variations of biomass concentration and shaking speed did not have a pronounced effect on the bioregeneration efficiency. The duration and efficiency of bioregeneration process were greatly affected by the chemical structures of mono-azo dyes to which the biomasses were acclimated.

Matched MeSH terms: Oxygen; Biological Oxygen Demand Analysis
Fulltext Characterization of vancomycin-resistant Enterococcus isolates from broilers in Selangor, Malaysia

Getachew YM, Hassan L, Zakaria Z, Saleha AA, Kamaruddin MI, Che Zalina MZ

Trop Biomed, 2009 Dec;26(3):280-8.
PMID: 20237442 MyJurnal

Vancomycin-resistant Enterococcus (VRE) is an emerging nosocomial pathogen in humans. The use of antibiotics in human therapy and in the production of food animals has been incriminated in the emergence of this organism. The present study describes the distribution of VRE species, the vancomycin-resistant genes detected, the vancomycin resistance pattern observed, and the genetic diversity of the isolates found in live broiler chickens in Malaysia. Overall 140 VRE were isolated with species comprising Enterococcus faecalis (48%), Enterococcus faecium (25.7%), Enterococcus gallinarum (12.1%), Enterococcus casseliflavus (1.4%) and other Enterococcus species (12.8%). Vancomycin resistance gene vanA and intrinsic genes vanC1 and vanC2/3 were detected in the study population. VanA was detected in 15 (63.9%) of E. faecium, 23 (22.4%) of E. faecalis and in 3 (17.6%) E. gallinarum isolates. E-test was conducted on randomly selected 41 of the isolates and the minimum inhibition concentration (MIC) of vancomycin for five (11.9%) of tested isolates is more than 256 μg/ml. Genotypic analysis using random amplified polymorphic DNA (RAPD) showed genetic diversity within the Enterococcus species.

Matched MeSH terms: Carbon-Oxygen Ligases/genetics
Fulltext Are Oxidative Stress and Inflammation Mediators of Bone Loss Due to Estrogen Deficiency? A Review of Current Evidence

Mohamad NV, Ima-Nirwana S, Chin KY

Endocr Metab Immune Disord Drug Targets, 2020;20(9):1478-1487.
PMID: 32496996 DOI: 10.2174/1871530320666200604160614

Osteoporosis is one of the major health issues associated with menopause-related estrogen deficiency. Various reports suggest that the hormonal changes related to menopausal transition may lead to the derangement of redox homeostasis and ultimately oxidative stress. Estrogen deficiency and oxidative stress may enhance the expression of genes involved in inflammation. All these factors may contribute, in synergy, to the development of postmenopausal osteoporosis. Previous studies suggest that estrogen may act as an antioxidant to protect the bone against oxidative stress, and as an antiinflammatory agent in suppressing pro-inflammatory and pro-osteoclastic cytokines. Thus, the focus of the current review is to examine the relationship between estrogen deficiency, oxidative stress and inflammation, and the impacts of these phenomena on skeletal health in postmenopausal women.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Molecular and Immunological Mechanisms Underlying the Various Pharmacological Properties of the Potent Bioflavonoid, Rutin

Yong DOC, Saker SR, Chellappan DK, Madheswaran T, Panneerselvam J, Choudhury H, et al.

Endocr Metab Immune Disord Drug Targets, 2020;20(10):1590-1596.
PMID: 32359343 DOI: 10.2174/1871530320666200503053846

The application of medicinal plants has captured the interest of researchers in recent times due to their potent therapeutic properties and a better safety profile. The prominent role of herbal products in treating and preventing multiple diseases dates back to ancient history and most of the modern drugs today originated from their significant sources owing to their ability to control multiple targets via different signalling pathways. Among them, flavonoids consist of a large group of polyphenols, which are well known for their various therapeutic benefits. Rutin is considered one of the attractive phytochemicals and important flavonoids in the pharmaceutical industry due to its diverse pharmacological activities via various underlying molecular mechanisms. It is usually prescribed for various disease conditions such as varicosities, haemorrhoids and internal haemorrhage. In this review, we have discussed and highlighted the different molecular mechanisms attributed to the various pharmacological activities of rutin, such as antioxidant, anti-inflammatory, anticancer, anti-allergic and antidiabetic. This review will be beneficial to herbal, biological and molecular scientists in understanding the pharmacological relevance of rutin at the molecular level.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Fulltext Studying neuroprotective effect of Atorvastatin as a small molecule drug on high glucose-induced neurotoxicity in undifferentiated PC12 cells: role of NADPH oxidase

Rayegan S, Dehpour AR, Sharifi AM

Metab Brain Dis, 2017 02;32(1):41-49.
PMID: 27476541 DOI: 10.1007/s11011-016-9883-1

Overproduction of reactive oxygen species (ROS) by NADPH oxidase (NOX) activation has been considered the essential mechanism induced by hyperglycemia in various tissues. However, there is no comprehensive study on the role of NOXs in high glucose (HG)-induced toxic effect in neural tissues. Recently, a therapeutic strategy in oxidative related pathologies has been introduced by blocking the undesirable actions of NOX enzymes by small molecules. The protective roles of Statins in ameliorating oxidative stress by NOX inhibition have been shown in some tissues except neural. We hypothesized then, that different NOXs may have role in HG-induced neural cell injury. Furthermore, we postulate that Atorvastatin as a small molecule may modulate this NOXs activity to protect neural cells. Undifferentiated PC12 cells were treated with HG (140 mM/24 h) in the presence and absence of Atorvastatin (1 μM/96 h). The cell viability was measured by MTT assay and the gene and protein expressions profile of NOX (1-4) were determined by RT-PCR and western blotting, respectively. Levels of ROS and malondialdehyde (MDA) were also evaluated. Gene and protein expression levels of NOX (1-4) and consequently ROS and MDA levels were elevated in HG-treated PC12 cells. Atorvastatin could significantly decrease HG-induced NOXs, ROS and MDA elevation and improve impaired cell viability. It can be concluded that HG could elevate NOXs activity, ROS and MDA levels in neural tissues and Atorvastatin as a small molecule NOX inhibitor drug may prevent and delay diabetic complications, particularly neuropathy.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Fulltext Oxygen tension modulates the effects of TNFα in compressed chondrocytes

Tilwani RK, Vessillier S, Pingguan-Murphy B, Lee DA, Bader DL, Chowdhury TT

Inflamm Res, 2017 Jan;66(1):49-58.
PMID: 27658702 DOI: 10.1007/s00011-016-0991-5

OBJECTIVE AND DESIGN: Oxygen tension and biomechanical signals are factors that regulate inflammatory mechanisms in chondrocytes. We examined whether low oxygen tension influenced the cells response to TNFα and dynamic compression.
MATERIALS AND METHODS: Chondrocyte/agarose constructs were treated with varying concentrations of TNFα (0.1-100 ng/ml) and cultured at 5 and 21 % oxygen tension for 48 h. In separate experiments, constructs were subjected to dynamic compression (15 %) and treated with TNFα (10 ng/ml) and/or L-NIO (1 mM) at 5 and 21 % oxygen tension using an ex vivo bioreactor for 48 h. Markers for catabolic activity (NO, PGE2) and tissue remodelling (GAG, MMPs) were quantified by biochemical assay. ADAMTS-5 and MMP-13 expression were examined by real-time qPCR. 2-way ANOVA and a post hoc Bonferroni-corrected t test were used to analyse data.
RESULTS: TNFα dose-dependently increased NO, PGE2 and MMP activity (all p oxygen tension than 21 %. The induction of catabolic mediators by TNFα was reduced by dynamic compression and/or L-NIO (all p oxygen tension and this response was reduced with TNFα or reversed with L-NIO.
CONCLUSIONS: The present findings revealed that TNFα increased production of NO, PGE2 and MMP activity at 5 % oxygen tension. The effects induced by TNFα were reduced by dynamic compression and/or the NOS inhibitor, linking both types of stimuli to reparative activities. Future therapeutics should develop oxygen-sensitive antagonists which are directed to interfering with the TNFα-induced pathways.

Matched MeSH terms: Oxygen/physiology*
Optimization of operating parameters of novel composite adsorbent for organic pollutants removal from POME using response surface methodology

Adeleke AO, Latiff AAA, Al-Gheethi AA, Daud Z

Chemosphere, 2017 May;174:232-242.
PMID: 28171839 DOI: 10.1016/j.chemosphere.2017.01.110

The present work aimed to develop a novel composite material made up of activated cow bone powder (CBP) as a starting material for reducing chemical oxygen demand (COD) and ammonia-nitrogen (NH3N) from palm oil mill effluent (POME). The optimization of the reduction efficiency was investigated using response surface methodology (RSM). Six independent variables used in the optimization experiments include pH (4-10), speed (0.27-9.66 rcf), contact time (2-24 h), particle size (1-4.35 mm), dilution factor (100-500) and adsorbent dosage (65-125 g/L). The chemical functional groups were determined using Fourier transform irradiation (FTIR). The elemental composition were detected using SEM-EDX, while thermal decomposition was investigated using thermo gravimetric analysis (TGA) in order to determine the effects of carbonization temperature on the adsorbent. The results revealed that the optimal reduction of COD and NH3N from raw POME was observed at pH 10, 50 rpm, within 2 h and 3 mm of particle size as well as at dilution factor of 500 and 125 g L-1 of adsorbent dosage, the observed and predicted reduction were 89.60 vs. 85.01 and 75.61 vs. 74.04%, respectively for COD and NH3N. The main functional groups in the adsorbent were OH, NH, CO, CC, COC, COH, and CH. The SEM-EDX analysis revealed that the CBP-composite has a smooth surface with high contents of carbon. The activated CBP has very stable temperature profile with no significant weight loss (9.85%). In conclusion, the CBP-composite investigated here has characteristics high potential for the remediation of COD and NH3N from raw POME.

Matched MeSH terms: Biological Oxygen Demand Analysis*
Modified APHA closed-tube reflux colorimetric method for TOC determination in water and wastewater

Salihu SO, Bakar NKA

Environ Monit Assess, 2018 May 30;190(6):369.
PMID: 29850927 DOI: 10.1007/s10661-018-6727-y

The analysis of total organic carbon (TOC) by the American Public Health Association (APHA) closed-tube reflux colorimetric method requires potassium dichromate (K2Cr2O7), silver sulfate (AgSO4), and mercury (HgSO4) sulfate in addition to large volumes of both reagents and samples. The method relies on the release of oxygen from dichromate on heating which is consumed by carbon associated with organic compounds. The method risks environmental pollution by discharging large amounts of chromium (VI) and silver and mercury sulfates. The present method used potassium monochromate (K2CrO4) to generate the K2Cr2O7 on demand in the first phase. In addition, miniaturizing the procedure to semi microanalysis decreased the consumption of reagents and samples. In the second phase, mercury sulfate was eliminated as part of the digestion mixture through the introduction of sodium bismuthate (NaBiO3) for the removal of chlorides from the sample. The modified method, the potassium monochromate closed-tube colorimetry with sodium bismuthate chloride removal (KMCC-Bi), generates the potassium dichromate on demand and eliminates mercury sulfate. The semi microanalysis procedure leads to a 60% reduction in sample volume and ≈ 33.33 and 60% reduction in monochromate and silver sulfate consumption respectively. The LOD and LOQ were 10.17 and 33.90 mg L-1 for APHA, and 4.95 and 16.95 mg L-1 for KMCC-Bi. Recovery was between 83 to 98% APHA and 92 to 104% KMCC-Bi, while the RSD (%) ranged between 0.8 to 5.0% APHA and 0.00 to 0.62% KMCC-Bi. The method was applied for the UV-Vis spectrometry determination of COD in water and wastewater. Statistics was done by MINITAB 17 or MS Excel 2016. ᅟ Graphical abstract.

Matched MeSH terms: Oxygen/analysis
Bera Lake water quality, past and present situation

Gharibrezal M, Ashraf MA

J Environ Biol, 2016 09;37(5 Spec No):1097-1104.
PMID: 29989741

Bera Lake is the largest natural fresh water reservoir in Malaysia. It has vital environmental and ecological importance for human and wild life. Nevertheless, water quality of this lake has been degraded during the last few decades due to land development projects at catchment area. Therefore, a comprehensive water quality assessment of Bera Lake was implemented in order to compare current water quality with the implementation of land development projects. In situ water quality surveying was implemented using calibrated full option Hydrolab DS 5. Eleven parameters viz., temperature, depth of sampling, salinity, Turbidity, total dried solid, pH, NH4(+), N03(-), Cl(-), saturation percentage of dissolved oxygen, specific conductivity were recorded in fifty one stations at 0.2h, 0.5h, and 0.8h depth. National Water Quality Standards for Malaysia (NWQS) and Water Quality were used to evaluate Bera Lake quality based on previous and resultant data. Vertical water quality analysis revealed a clear stratification in Bera Lake water profile in terms of temperature, dissolved oxygen, chloride (Cl(-)), nitrate (NO(3)), pH and specific conductivity (EC) parameters. Results clearly demonstrate the important role of land use changes since 1972 in the physico-chemical condition of water quality at Bera Lake. Classifications of water quality before and after land development project were calculated as class II and class V, respectively. A long-term and comprehensive monitoring of water quality assessment is recommended in order to reach plan of sustainable water resources use with conservation approach.

Matched MeSH terms: Oxygen/chemistry
Differential Effects of 7 and 16 Groups of Muscle Relaxation Training Following Repeated Submaximal Intensity Exercise in Young Football Players

Sharifah Maimunah SM, Hashim HA

Percept Mot Skills, 2016 Feb;122(1):227-37.
PMID: 27420318 DOI: 10.1177/0031512515625383

This study compares two versions of progressive muscle relaxation (PMR) training (7 and 16 muscle groups) on oxygen consumption (VO2), heart rates, rating of perceived exertion and choice reaction time. Football (soccer) players (N = 26; M age = 13.4 yr., SD = 0.5) were randomly assigned to either 7 muscle groups PMR, 16 muscle groups PMR, or a control group. PMR training requires the participants to tense a muscle, hold the muscle contraction, and then relax it. Measurement was conducted prior to and after the completion of 12 sessions of PMR. The dependent variables were measured following four bouts of intermittent exercise consisting of 12 min. of running at 60% VO2max for 10 min. followed by running at 90% VO2max for 2 min. with a 3-min. rest for each bout. Lower VO2, heart rate, perceived exertion, and quicker reaction time were expected in both relaxation groups compared to the control group. The results revealed a significant reduction in heart rates and choice reaction time for both relaxation groups, but the longer version produced significantly quicker choice reaction time.

Matched MeSH terms: Oxygen Consumption/physiology*
Pharmacological insights into antioxidants against colorectal cancer: A detailed review of the possible mechanisms

Gothai S, Muniandy K, Gnanaraj C, Ibrahim IAA, Shahzad N, Al-Ghamdi SS, et al.

Biomed Pharmacother, 2018 Nov;107:1514-1522.
PMID: 30257369 DOI: 10.1016/j.biopha.2018.08.112

Colorectal cancer (CRC) is ranked as the fourth most lethal and commonly diagnosed cancer in the world according to the National Cancer Institute's latest report. Treatment methods for CRC are constantly being studied for advancement, which leads for more clinically effective cancer curing strategy. Patients with prolonged chronic inflammation caused by ulcerative colitis or similar inflammatory bowel disease are known to have high risks of developing CRC. But at a molecular level, oxidative stress due to reactive oxygen species (ROS) is an important trigger for cancer. Hence, in recent years, exogenous antioxidants have been immensely experimented in pre-clinical and clinical trials, considering it as a potential cure for CRC. Significantly, potential antioxidant compounds especially derivatives of medicinal plants have received great attention in the current research trend for CRC treatment. Though antioxidant compounds seem to have beneficial properties for the treatment of CRC, there are also limitations for pure compounds to be tested clinically. Therefore, this review aims to delineate the pharmacological awareness among researchers on using antioxidant compounds to treat CRC and the measures taken to prove the effectiveness of such compounds as impending drug candidates for CRC treatment in modern medication.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Synergistic antibacterial actions of graphene oxide and antibiotics towards bacteria and the toxicological effects of graphene oxide on human epidermal keratinocytes

Pulingam T, Thong KL, Appaturi JN, Nordin NI, Dinshaw IJ, Lai CW, et al.

Eur J Pharm Sci, 2020 Jan 15;142:105087.
PMID: 31626968 DOI: 10.1016/j.ejps.2019.105087

Graphene oxide (GO) has displayed antibacterial activity that has been investigated in the past, however, information on synergistic activity of GO with conventional antibiotics is still lacking. The objectives of the study were to determine the combinatorial actions of GO and antibiotics against Gram-positive and Gram-negative bacteria and the toxicological effects of GO towards human epidermal keratinocytes (HaCaT). Interactions at molecular level between GO and antibiotics were analyzed using Attenuated Total Reflectance-Fourier-transform infrared spectroscopy (ATR-FTIR). Changes in the antibacterial activity of antibiotics towards bacteria through the addition of GO was investigated. Toxicity of GO towards HaCaT cells were examined as skin cells play a role as the first line of defense of the human body. The ATR-FTIR characterizations of GO and antibiotics showed adsorption of tested antibiotics onto GO. The combinatorial antibacterial activity of GO and antibiotics were found to increase when compared to GO or antibiotic alone. This was attributed to the ability of GO to disrupt bacterial membrane to allow for better adsorption of antibiotics. Cytotoxicity of GO was found to be dose-dependent towards HaCaT cell line, it is found to impose negligible toxic effects against the skin cells at concentration below 100 μg/mL.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Fulltext The Molecular Mechanism of Vitamin E as a Bone-Protecting Agent: A Review on Current Evidence

Wong SK, Mohamad NV, Ibrahim N', Chin KY, Shuid AN, Ima-Nirwana S

Int J Mol Sci, 2019 Mar 22;20(6).
PMID: 30909398 DOI: 10.3390/ijms20061453

Bone remodelling is a tightly-coordinated and lifelong process of replacing old damaged bone with newly-synthesized healthy bone. In the bone remodelling cycle, bone resorption is coupled with bone formation to maintain the bone volume and microarchitecture. This process is a result of communication between bone cells (osteoclasts, osteoblasts, and osteocytes) with paracrine and endocrine regulators, such as cytokines, reactive oxygen species, growth factors, and hormones. The essential signalling pathways responsible for osteoclastic bone resorption and osteoblastic bone formation include the receptor activator of nuclear factor kappa-B (RANK)/receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG), Wnt/β-catenin, and oxidative stress signalling. The imbalance between bone formation and degradation, in favour of resorption, leads to the occurrence of osteoporosis. Intriguingly, vitamin E has been extensively reported for its anti-osteoporotic properties using various male and female animal models. Thus, understanding the underlying cellular and molecular mechanisms contributing to the skeletal action of vitamin E is vital to promote its use as a potential bone-protecting agent. This review aims to summarize the current evidence elucidating the molecular actions of vitamin E in regulating the bone remodelling cycle.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Effects of diarylpentanoid analogues of curcumin on chemiluminescence and chemotactic activities of phagocytes

Jantan I, Bukhari SN, Lajis NH, Abas F, Wai LK, Jasamai M

J Pharm Pharmacol, 2012 Mar;64(3):404-12.
PMID: 22309272 DOI: 10.1111/j.2042-7158.2011.01423.x

A series of 43 curcumin diarylpentanoid analogues were synthesized and evaluated for their inhibitory effects on the chemiluminescence and chemotactic activity of phagocytes in vitro.

Matched MeSH terms: Reactive Oxygen Species/pharmacology
Inhibition of L-NAME-induced hypertension by combined treatment with apocynin and catalase: the role of Nox 4 expression

Chia TY, Murugaiyah V, Khan NA, Sattar MA, Abdulla MH, Johns EJ, et al.

Physiol Res, 2021 03 17;70(1):13-26.
PMID: 33728924

Reactive oxygen species (ROS) such as superoxide (O2-) generated by NAD(P)H oxidases have emerged as important molecules in blood pressure regulation. This study investigated the effect of apocynin and catalase on blood pressure and renal haemodynamic and excretory function in an L-NAME induced hypertension model. Forty Male Wistar-Kyoto (WKY) rats (n=8 per group) were treated with either: vehicle (WKY-C); L-NAME (WKY-L, 15 mg/kg/day in drinking fluid); WKY-L given apocynin to block NAD(P)H oxidase (WKY-LApo, 73 mg/kg/day in drinking water.); WKY-L given catalase to enhance ROS scavenging (WKY-LCat, 10000 U/kg/day i.p.); and WKY-L receiving apocynin plus catalase (WKY-LApoCat) daily for 14 days. L-NAME elevated systolic blood pressure (SBP), 116+/-1 to 181±4 mmHg, reduced creatinine clearance, 1.69+/-0.26 to 0.97+/-0.05 ml/min/kg and fractional sodium excretion, 0.84+/-0.09 to 0.55+/-0.09 % at day 14. Concomitantly, plasma malondialdehyde (MDA) increased six fold, while plasma total superoxide dismutase (T-SOD), plasma nitric oxide (NO) and plasma total antioxidant capacity (T-AOC) were decreased by 60-70 % and Nox 4 mRNA expression was increased 2-fold. Treatment with apocynin and catalase attenuated the increase in SBP and improved renal function, enhanced antioxidative stress capacity and reduced the magnitude of Nox4 mRNAs expression in the L-NAME treated rats. This study demonstrated that apocynin and catalase offset the development of L-NAME induced hypertension, renal dysfunction and reduced oxidative stress status, possibly contributed by a reduction in Nox4 expression during NOS inhibition. These findings would suggest that antioxidant compounds such as apocynin and catalase have potential in treating cardiovascular diseases.

Matched MeSH terms: Reactive Oxygen Species/metabolism*
Fulltext Effects of palm oil tocotrienol-rich fraction on biochemical and morphological alterations of liver in fenitrothion-treated rats

Jayusman PA, Budin SB, Ghazali AR, Taib IS, Louis SR

Pak J Pharm Sci, 2014 Nov;27(6):1873-80.
PMID: 25362611

Indiscriminate application of organophosphate (OP) pesticides has led to environmental pollution and severe health problems. The aim of the present study was to evaluate the effect of palm oil tocotrienol-rich fraction (TRF) on biochemical and morphological changes of the liver in rats treated with fenitrothion (FNT), a type of OP pesticide. A total of 28 male Sprague-Dawley rats were divided into four groups; control group, TRF-supplemented group, FNT-treated group and TRF+FNT group. TRF (200 mg/kg) was supplemented 30 minutes prior to FNT (20 mg/kg) administration, both orally for 28 consecutive days. Following 28 days of treatment, plasma biochemical changes and liver morphology were evaluated. The body and absolute liver weights were significantly elevated in TRF+FNT group compared to FNT group. TRF administration significantly decreased the total protein level and restored the activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in TRF + FNT group. In contrast, total bilirubin level, γ-glutamyltranferase (GGT) and cholinesterase activity in TRF + FNT group did not significantly differ from FNT group. Administration of TRF also prevented FNT-induced morphological changes of liver as observed by electron microscope. In conclusion, TRF supplementation showed potential protective effect towards biochemical and ultrastructural changes in liver induced by FNT.

Matched MeSH terms: Reactive Oxygen Species/metabolism

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