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Fulltext Protecting mechanism of Swietenia macrophylla ethanol extract nanoparticle on streptozotocin induced renal damage in rat

Kurnijasanti R, Wardani G, Mustafa MR, Sudjarwo SA

Open Vet J, 2023 Dec;13(12):1623-1630.
PMID: 38292712 DOI: 10.5455/OVJ.2023.v13.i12.12

BACKGROUND: Hyperglycemia increases reactive oxygen species (ROS), which contributes to diabetic complications such as kidney cell damage. Antioxidant administration could inhibit ROS and kidney cell damage commonly seen in hyperglycemia.
AIM: We want to demonstrate that the antioxidant properties of Swietenia macrophylla ethanol extract nanoparticles can prevent kidney cell damage brought on by streptozotocin (STZ) in the current investigation.
METHODS: This study employs high-energy ball milling to produce nanoparticles from S. macrophylla extract. Additionally, dynamic light scattering (DLS) is utilized to characterize the nanoparticle sizes of the S. macrophylla ethanol extract. Five groups, each consisting of 8 rats, were formed from 40 rats. Control rats received distilled water, the diabetic rats were administered STZ injections, while S. macrophylla rats were given S. macrophylla extract nanoparticles orally and STZ injection. After the trial, blood from a rat was drawn intracardially to check the levels of blood urea nitrogen (BUN) and creatinine. The levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), and malondialdehyde (MDA) were then assessed in kidney tissue samples. Histological alterations were evaluated in kidney section samples.
RESULTS: A DLS analysis estimated the size of the S. macrophylla ethanol extract nanoparticles to be about 91.50 ± 23.06 nm. BUN and creatinine levels were significantly raised after STZ treatment. STZ significantly decreased SOD and GPx levels in kidney tissue while raising MDA levels (p < 0.05). Swietenia macrophylla ethanol extract nanoparticle caused the decreased levels of BUN and creatinine in blood to normal levels (p < 0.05), indicating that S. macrophylla ethanol extract prevented the STZ-induced kidney cell damage. Additionally, S. macrophylla nanoparticles significantly raise GPx and SOD levels in kidney tissue while lowering MDA levels (p < 0.05). These actions are thought to have prevented kidney histological alterations (degeneration and necrosis) in diabetic rats.
CONCLUSION: According to these results, the anti-oxidative stress properties of S. macrophylla nanoparticles make them potentially effective nephroprotective therapies for STZ-induced kidney cell damage.

Matched MeSH terms: Reactive Oxygen Species/pharmacology
Biocompatibility of bio based calcium carbonate nanocrystals aragonite polymorph on NIH 3T3 fibroblast cell line

Kamba AS, Ismail M, Ibrahim TA, Zakaria ZA

Afr J Tradit Complement Altern Med, 2014;11(4):31-8.
PMID: 25392577

BACKGROUND: Currently, there has been extensive research interest for inorganic nanocrystals such as calcium phosphate, iron oxide, silicone, carbon nanotube and layered double hydroxide as a drug delivery system especially in cancer therapy. However, toxicological screening of such particles is paramount importance before use as delivery carrier. In this study we examine the biocompatibility of CaCO3 nanocrystal on NIH 3T3 cell line.
MATERIAL AND METHODS: Transmission and field emission scanning electron microscopy (TEM and FESEM) were used for the characterisation of CaCO3 nanocrystals. Cytotoxicity and genotoxic effect of calcium carbonate nanocrystals in cultured mouse embryonic fibroblast NIH 3T3 cell line using various bioassays including MTT, and Neutral red/Trypan blue double-staining assays. LDH, BrdU and reactive oxygen species were used for toxicity analysis. Cellular morphology was examined by scanning electron microscopy (SEM) and confocal fluorescence microscope.
RESULTS: The outcome of the analyses revealed a clear rod-shaped aragonite polymorph of calcium carbonate nanocrystal. The analysed cytotoxic and genotoxicity of CaCO3 nanocrystal on NIH 3T3 cells using different bioassays revealed no significance differences as compared to control. A slight decrease in cell viability was noticed when the cells were exposed to higher concentrations of 200 to 400 µg/ml, while increase in ROS generation and LDH released at 200 and 400 µg/ml was observed.
CONCLUSIONS: The study has shown that CaCO3 nanocrystal is biocompatible and non toxic to NIH 3T3 fibroblast cells. The analysed results offer a promising potential of CaCO3 nanocrystal for the development of intracellular drugs, genes and other macromolecule delivery systems.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Normobaric hyperoxia treatment prevents early alteration in dopamine level in mice striatum after fluid percussion injury: a biochemical approach

Muthuraju S, Islam MR, Pati S, Jaafar H, Abdullah JM, Yusoff KM

Int J Neurosci, 2015;125(9):686-92.
PMID: 25180987 DOI: 10.3109/00207454.2014.961065

Dopamine (DA) is one of the key neurotransmitters in the striatum, which is functionally important for a variety of cognitive and motor behaviours. It is known that the striatum is vulnerable to damage from traumatic brain injury (TBI). However, a therapeutic approach has not yet been established to treat TBI. Hence, the present work aimed to evaluate the ability of Normobaric hyperoxia treatment (NBOT) to recover dopaminergic neurons following a fluid percussion injury (FPI) as a TBI experimental animal model. To examine this, mice were divided into four groups: (i) Control, (ii) Sham, (iii) FPI and (iv) FPI+NBOT. Mice were anesthetized and surgically prepared for FPI in the striatum and immediate exposure to NBOT at various time points (3, 6, 12 and 24 h). Dopamine levels were then estimated post injury by utilizing a commercially available ELISA method specific to DA. We found that DA levels were significantly reduced at 3 h, but there was no reduction at 6, 12 and 24 h in FPI groups when compared to the control and sham groups. Subjects receiving NBOT showed consistent increased DA levels at each time point when compared with Sham and FPI groups. These results suggest that FPI may alter DA levels at the early post-TBI stages but not in later stages. While DA levels increased in 6, 12 and 24 h in the FPI groups, NBOT could be used to accelerate the prevention of early dopaminergic neuronal damage following FPI injury and improve DA levels consistently.

Matched MeSH terms: Oxygen Inhalation Therapy/methods*
Mitochondrial dysfunction as a central event for mechanisms underlying insulin resistance: the roles of long chain fatty acids

Hafizi Abu Bakar M, Kian Kai C, Wan Hassan WN, Sarmidi MR, Yaakob H, Zaman Huri H

Diabetes Metab Res Rev, 2015 Jul;31(5):453-75.
PMID: 25139820 DOI: 10.1002/dmrr.2601

Insulin resistance is characterized by hyperglycaemia, dyslipidaemia and oxidative stress prior to the development of type 2 diabetes mellitus. To date, a number of mechanisms have been proposed to link these syndromes together, but it remains unclear what the unifying condition that triggered these events in the progression of this metabolic disease. There have been a steady accumulation of data in numerous experimental studies showing the strong correlations between mitochondrial dysfunction, oxidative stress and insulin resistance. In addition, a growing number of studies suggest that the raised plasma free fatty acid level induced insulin resistance with the significant alteration of oxidative metabolism in various target tissues such as skeletal muscle, liver and adipose tissue. In this review, we herein propose the idea of long chain fatty acid-induced mitochondrial dysfunctions as one of the key events in the pathophysiological development of insulin resistance and type 2 diabetes. The accumulation of reactive oxygen species, lipotoxicity, inflammation-induced endoplasmic reticulum stress and alterations of mitochondrial gene subset expressions are the most detrimental that lead to the developments of aberrant intracellular insulin signalling activity in a number of peripheral tissues, thereby leading to insulin resistance and type 2 diabetes.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Is First-Order Vector Autoregressive Model Optimal for fMRI Data?

Ting CM, Seghouane AK, Khalid MU, Salleh ShH

Neural Comput, 2015 Sep;27(9):1857-71.
PMID: 26161816 DOI: 10.1162/NECO_a_00765

We consider the problem of selecting the optimal orders of vector autoregressive (VAR) models for fMRI data. Many previous studies used model order of one and ignored that it may vary considerably across data sets depending on different data dimensions, subjects, tasks, and experimental designs. In addition, the classical information criteria (IC) used (e.g., the Akaike IC (AIC)) are biased and inappropriate for the high-dimensional fMRI data typically with a small sample size. We examine the mixed results on the optimal VAR orders for fMRI, especially the validity of the order-one hypothesis, by a comprehensive evaluation using different model selection criteria over three typical data types--a resting state, an event-related design, and a block design data set--with varying time series dimensions obtained from distinct functional brain networks. We use a more balanced criterion, Kullback's IC (KIC) based on Kullback's symmetric divergence combining two directed divergences. We also consider the bias-corrected versions (AICc and KICc) to improve VAR model selection in small samples. Simulation results show better small-sample selection performance of the proposed criteria over the classical ones. Both bias-corrected ICs provide more accurate and consistent model order choices than their biased counterparts, which suffer from overfitting, with KICc performing the best. Results on real data show that orders greater than one were selected by all criteria across all data sets for the small to moderate dimensions, particularly from small, specific networks such as the resting-state default mode network and the task-related motor networks, whereas low orders close to one but not necessarily one were chosen for the large dimensions of full-brain networks.

Matched MeSH terms: Oxygen/blood
The effects of modified exponential tapering technique on perceived exertion, heart rate, time trial performance, VO2max and power output among highly trained junior cyclists

Ishak A, Hashim HA, Krasilshchikov O

J Sports Med Phys Fitness, 2016 Sep;56(9):961-7.
PMID: 26004044

BACKGROUND: The present study investigated the effects of a 2-week modified exponential taper on physiological adaptation and time trial performance among junior cyclists.
METHODS: Participants (N.=27) with the mean age of 16.95±0.8 years, height of 165.6±6.1 cm and weight of 54.19±8.1 kg were matched into either modified exponential taper (N.=7), normal exponential taper (N.=7), or control (N.=7) groups using their initial VO2max values. Both experimental groups followed a 12-week progressive endurance training program and subsequently, a 2-week tapering phase. A simulated 20-km time trial performance along with VO2max, power output, heart rate and rating of perceived exertion were measured at baseline, pre and post-taper. One way ANOVA was used to analyze the difference between groups before the start of the intervention while mixed factorial ANOVA was used to analyze the difference between groups across measurement sessions. When homogeneity assumption was violated, the Greenhouse-Geisser Value was used for the corrected values of the degrees of freedom for the within subject factor the analysis.
RESULTS: Significant interactions between experimental groups and testing sessions were found in VO2max (F=6.67, df=4, P<0.05), power output (F=5.02, df=4, P<0.05), heart rate (F=10.87, df=2.51, P<0.05) rating of perceived exertion (F=13.04, df=4, P<0.05) and 20KM time trial (F=4.64, df=2.63, P<0.05). Post-hoc analysis revealed that both types of taper exhibited positive effects compared to the non-taper condition in the measured performance markers at post-taper while no different were found between the two taper groups.
CONCLUSIONS: It was concluded that both taper protocols successfully inducing physiological adaptations among the junior cyclists by reducing the volume and maintaining the intensity of training.

Matched MeSH terms: Oxygen Consumption/physiology*
Decoding of visual information from human brain activity: A review of fMRI and EEG studies

Zafar R, Malik AS, Kamel N, Dass SC, Abdullah JM, Reza F, et al.

J Integr Neurosci, 2015 Jun;14(2):155-68.
PMID: 25939499 DOI: 10.1142/S0219635215500089

Brain is the command center for the body and contains a lot of information which can be extracted by using different non-invasive techniques. Electroencephalography (EEG), Magnetoencephalography (MEG) and functional magnetic resonance imaging (fMRI) are the most common neuroimaging techniques to elicit brain behavior. By using these techniques different activity patterns can be measured within the brain to decode the content of mental processes especially the visual and auditory content. This paper discusses the models and imaging techniques used in visual decoding to investigate the different conditions of brain along with recent advancements in brain decoding. This paper concludes that it's not possible to extract all the information from the brain, however careful experimentation, interpretation and powerful statistical tools can be used with the neuroimaging techniques for better results.

Matched MeSH terms: Oxygen/blood
Fulltext Major pathophysiological correlations of rosacea: a complete clinical appraisal

Vemuri RC, Gundamaraju R, Sekaran SD, Manikam R

Int J Med Sci, 2015;12(5):387-96.
PMID: 26005373 DOI: 10.7150/ijms.10608

Rosacea is a characteristic cutaneous disorder with a diverse clinical manifestations ranging from facial vascular hyper-reactivity to sebaceous gland hyperplasia. Many theories on pathophysiology of rosacea were proposed over the past decade, however the pathogenicity is poorly understood.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Muscle synergies during incremental rowing VO2max test of collegiate rowers and untrained subjects

Shaharudin S, Agrawal S

J Sports Med Phys Fitness, 2016 Sep;56(9):980-9.
PMID: 25732319

BACKGROUND: The purpose of this study was to evaluate the muscle synergies during incremental rowing VO2 max Test of collegiate rowers and untrained subjects. As a power endurance sport, high aerobic capacity was one of the determinants of rowing performance. The modulation of muscle recruitment patterns following specific physiological demands was an indication of the robustness of muscle synergies composition which was overlooked in previous studies.
METHODS: Ten male collegiate rowers and physically active untrained subjects were recruited. Muscle synergies were extracted from 16 rowing-specific muscles using Principal Component Analysis with varimax rotation. Incremental rowing VO2 max Test was performed on slides ergometer (SE). Rowing performance and physiological variables were analyzed.
RESULTS: Rowers exerted greater power output, more energy expenditure and better rowing economy compared to untrained subjects. Rowers preferred to row slower with longer strokes compared to the untrained subjects. Three muscle synergies with high indices of similarity of waveform patterns were extracted in both groups. Significant association was found between muscle synergies and rowing economy.
CONCLUSIONS: The findings of this study showed that muscle synergies were robust during aerobic-dominant activity for collegiate rowers and untrained subjects. Rowers and coaches could utilize the findings by emphasizing on muscle coordination training, which may enhance the rowing economy.

Matched MeSH terms: Oxygen Consumption/physiology*
Fulltext Phytoagents for cancer management: regulation of nucleic acid oxidation, ROS, and related mechanisms

Lee WL, Huang JY, Shyur LF

Oxid Med Cell Longev, 2013;2013:925804.
PMID: 24454991 DOI: 10.1155/2013/925804

Accumulation of oxidized nucleic acids causes genomic instability leading to senescence, apoptosis, and tumorigenesis. Phytoagents are known to reduce the risk of cancer development; whether such effects are through regulating the extent of nucleic acid oxidation remains unclear. Here, we outlined the role of reactive oxygen species in nucleic acid oxidation as a driving force in cancer progression. The consequential relationship between genome instability and cancer progression highlights the importance of modulation of cellular redox level in cancer management. Current epidemiological and experimental evidence demonstrate the effects and modes of action of phytoagents in nucleic acid oxidation and provide rationales for the use of phytoagents as chemopreventive or therapeutic agents. Vitamins and various phytoagents antagonize carcinogen-triggered oxidative stress by scavenging free radicals and/or activating endogenous defence systems such as Nrf2-regulated antioxidant genes or pathways. Moreover, metal ion chelation by phytoagents helps to attenuate oxidative DNA damage caused by transition metal ions. Besides, the prooxidant effects of some phytoagents pose selective cytotoxicity on cancer cells and shed light on a new strategy of cancer therapy. The "double-edged sword" role of phytoagents as redox regulators in nucleic acid oxidation and their possible roles in cancer prevention or therapy are discussed in this review.

Matched MeSH terms: Reactive Oxygen Species/metabolism*
Fulltext Enhancement of oxygen mass transfer and gas holdup using palm oil in stirred tank bioreactors with xanthan solutions as simulated viscous fermentation broths

Mohd Sauid S, Krishnan J, Huey Ling T, Veluri MV

Biomed Res Int, 2013;2013:409675.
PMID: 24350269 DOI: 10.1155/2013/409675

Volumetric mass transfer coefficient (kLa) is an important parameter in bioreactors handling viscous fermentations such as xanthan gum production, as it affects the reactor performance and productivity. Published literatures showed that adding an organic phase such as hydrocarbons or vegetable oil could increase the kLa. The present study opted for palm oil as the organic phase as it is plentiful in Malaysia. Experiments were carried out to study the effect of viscosity, gas holdup, and kLa on the xanthan solution with different palm oil fractions by varying the agitation rate and aeration rate in a 5 L bench-top bioreactor fitted with twin Rushton turbines. Results showed that 10% (v/v) of palm oil raised the kLa of xanthan solution by 1.5 to 3 folds with the highest kLa value of 84.44 h(-1). It was also found that palm oil increased the gas holdup and viscosity of the xanthan solution. The kLa values obtained as a function of power input, superficial gas velocity, and palm oil fraction were validated by two different empirical equations. Similarly, the gas holdup obtained as a function of power input and superficial gas velocity was validated by another empirical equation. All correlations were found to fit well with higher determination coefficients.

Matched MeSH terms: Oxygen/metabolism*
Performance of ANFIS versus MLP-NN dissolved oxygen prediction models in water quality monitoring

Najah A, El-Shafie A, Karim OA, El-Shafie AH

Environ Sci Pollut Res Int, 2014 Feb;21(3):1658-1670.
PMID: 23949111 DOI: 10.1007/s11356-013-2048-4

We discuss the accuracy and performance of the adaptive neuro-fuzzy inference system (ANFIS) in training and prediction of dissolved oxygen (DO) concentrations. The model was used to analyze historical data generated through continuous monitoring of water quality parameters at several stations on the Johor River to predict DO concentrations. Four water quality parameters were selected for ANFIS modeling, including temperature, pH, nitrate (NO3) concentration, and ammoniacal nitrogen concentration (NH3-NL). Sensitivity analysis was performed to evaluate the effects of the input parameters. The inputs with the greatest effect were those related to oxygen content (NO3) or oxygen demand (NH3-NL). Temperature was the parameter with the least effect, whereas pH provided the lowest contribution to the proposed model. To evaluate the performance of the model, three statistical indices were used: the coefficient of determination (R (2)), the mean absolute prediction error, and the correlation coefficient. The performance of the ANFIS model was compared with an artificial neural network model. The ANFIS model was capable of providing greater accuracy, particularly in the case of extreme events.

Matched MeSH terms: Oxygen/analysis*
Fulltext Fatigue index and fatigue rate during an anaerobic performance under hypohydrations

Naharudin MN, Yusof A

PLoS One, 2013;8(10):e77290.
PMID: 24204790 DOI: 10.1371/journal.pone.0077290

BACKGROUND: Since hypohydration commonly occurs in sports, studies on anaerobic exercise performance under this condition have been extensively carried out. When describing anaerobic performance, authors usually refer to a drop in anaerobic performance as fatigue index (FI) which is conventionally calculated using peak and low power data points. Meanwhile, another possible method in explaining anaerobic fatigue is using the rate constant which is derived from the exponential decline of power output known as fatigue rate (FR). Few studies have demonstrated that there was no change in anaerobic performance under mild hypohydrations.
PURPOSE: This study aimed to compare the kinetics of power output using FI and FR of an anaerobic performance (Wingate test) under 2, 3 and 4% state of hypohydrations.
METHOD: Thirty two collegiate cyclists (age = 22 ± 2 years; body weight = 71.45 ± 3.43 kg; height = 173.23 ± 0.04 cm) were matched using their baseline anaerobic peak power (APP) then randomly divided into 4 groups of EU (euhydrated), 2H, 3H and 4H respectively.
RESULTS: As expected the, FI, APP, anaerobic lower power (ALP) and rating of perceived exertion (RPE) did not show significant differences between and within the groups. However, the FR in 3H (0.018 ± 0.005 s(-1)) and 4H (0.019 ± 0.010 s(-1)) were significantly lower than EU (0.033 ± 0.012 s(-1)). Post-test FR also showed significant reduction in 3H and 4H compared to their pre-test values (p<0.05).
CONCLUSION: Despite the lack of changes in APP and RPE, subjects in 3H and 4H showed evidence of lower reduction of power output over time. The findings support earlier reports which showed no change in anaerobic performance under mild hypohydrations. The relatively lower FR suggests higher drive in maintaining power output under hypohydrations of 3 and 4% body weight.

Matched MeSH terms: Oxygen Consumption/physiology
Effects of endurance and high intensity training on ICAM-1 and VCAM-1 levels and arterial pressure in obese and normal weight adolescents

Kargarfard M, Lam ET, Shariat A, Asle Mohammadi M, Afrasiabi S, Shaw I, et al.

Phys Sportsmed, 2016 09;44(3):208-16.
PMID: 27291761 DOI: 10.1080/00913847.2016.1200442

OBJECTIVES: Obesity prevalence has increased in Iranian adolescents in recent years. However, few studies have examined the impact of intervention programs on this health issue. The main objective of this study was to evaluate the effects of 8-week endurance training (ET) and high intensity interval training (HIIT) on intercellular adhesion molecule-1(ICAM-1) and vascular adhesion molecule-1(VCAM-1) levels among obese and normal-weight male adolescents.
METHODS: Thirty obese and 30 normal-weight subjects were assigned to the ET, HIIT, or control group for eight weeks. Before and after the intervention, ICAM-1, VCAM-1, body weight, BMI, VO2max, and blood pressures were measured. SPSS (Version 21) was used for data analysis, and the significance level was set at p oxygen uptake

Matched MeSH terms: Oxygen Consumption/physiology
Fulltext Sphingosine 1-phosphate receptor 2 (S1P2) attenuates reactive oxygen species formation and inhibits cell death: implications for otoprotective therapy

Herr DR, Reolo MJ, Peh YX, Wang W, Lee CW, Rivera R, et al.

Sci Rep, 2016 Apr 15;6:24541.
PMID: 27080739 DOI: 10.1038/srep24541

Ototoxic drugs, such as platinum-based chemotherapeutics, often lead to permanent hearing loss through apoptosis of neuroepithelial hair cells and afferent neurons of the cochlea. There is no approved therapy for preventing or reversing this process. Our previous studies identified a G protein-coupled receptor (GPCR), S1P2, as a potential mediator of otoprotection. We therefore sought to identify a pharmacological approach to prevent cochlear degeneration via activation of S1P2. The cochleae of S1pr2(-/-) knockout mice were evaluated for accumulation of reactive oxygen species (ROS) with a nitro blue tetrazolium (NBT) assay. This showed that loss of S1P2 results in accumulation of ROS that precedes progressive cochlear degeneration as previously reported. These findings were supported by in vitro cell-based assays to evaluate cell viability, induction of apoptosis, and accumulation of ROS following activation of S1P2 in the presence of cisplatin. We show for the first time, that activation of S1P2 with a selective receptor agonist increases cell viability and reduces cisplatin-mediated cell death by reducing ROS. Cumulatively, these results suggest that S1P2 may serve as a therapeutic target for attenuating cisplatin-mediated ototoxicity.

Matched MeSH terms: Reactive Oxygen Species/metabolism*
Antioxidant modulation in restoring mitochondrial function in neurodegeneration

Pahrudin Arrozi A, Wan Ngah WZ, Mohd Yusof YA, Ahmad Damanhuri MH, Makpol S

Int J Neurosci, 2017 Mar;127(3):218-235.
PMID: 27074540 DOI: 10.1080/00207454.2016.1178261

Alzheimer's disease (AD) and Parkinson's disease (PD) are the leading causes of disability associated with neurodegeneration worldwide. These diseases are influenced by multiple genetic and environmental factors and share similar mechanisms as both are characterized by accumulation and aggregation of misfolded proteins - amyloid-beta (Aβ) in AD and α-synuclein in PD. Over the past decade, increasing evidence has shown that mitochondrial dysfunction and the generation of reactive oxygen species (ROS) are involved in the pathology of these diseases, and the contributions of these defects to the cellular and molecular changes that eventually cause neuronal death have been explored. Using mitochondrial protective agents, such as antioxidants, to combat ROS provides a new strategy for neurodegenerative treatment. In this review, we highlight the potential of multiple types of antioxidants, including vitamins, phytochemicals, fatty acids and minerals, as well as synthetic antioxidants specifically targeting the mitochondria, which can restore mitochondrial function, in the treatment of neurodegenerative disorders at both the pre-clinical and clinical stages by focusing on AD and PD.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Atherosclerotic cardiovascular disease: a review of initiators and protective factors

Ellulu MS, Patimah I, Khaza'ai H, Rahmat A, Abed Y, Ali F

Inflammopharmacology, 2016 Feb;24(1):1-10.
PMID: 26750181 DOI: 10.1007/s10787-015-0255-y

Atherosclerotic cardiovascular disease (CVD) is a collective term comprising of a group of disorders of the heart and blood vessels. These diseases are the largest cause of morbidity and premature death worldwide. Coronary heart disease and cerebrovascular disease (stroke) are the most frequently occurring diseases. The two major initiators involved in the development of atherosclerotic CVD are vascular production of reactive oxygen species (ROS) and lipid oxidation. In atherosclerosis development, ROS is associated with rapid loss of anti-inflammatory and anti-atherogenic activities of the endothelium-derived nitric oxide (NO(·)) resulting in endothelial dysfunction. In part involving activation of the transcription factor NF-κB, ROS have been involved in signaling cascades leading to vascular pro-inflammatory and pro-thrombotic gene expression. ROS is also a potent activator of matrix metalloproteinases (MMPs), which indicate plaque destabilization and rupture. The second initiator involved in atherosclerotic CVD is the oxidation of low-density lipoproteins (LDL). Oxidation of LDL in vessel wall leads to an inflammatory cascade that activates atherogenic pathway leading to foam cell formation. The accumulation of foam cells leads to fatty streak formation, which is the earliest visible atherosclerotic lesion. In contrast, the cardiac sarco/endoplasmic reticulum Ca(2+)-ATPase (SERCA2a) and hepatic apolipoprotein E (apoE) expression can improve cardiovascular function. SERCA2a regulates the cardiac contractile function by lowering cytoplasmic calcium levels during relaxation, and affecting NO(·) action in vascular cells, while apoE is a critical ligand in the plasma clearance of triglyceride- and cholesterol-rich lipoproteins.

Matched MeSH terms: Reactive Oxygen Species/metabolism*
Fulltext Degradation of Triazine-2-(14)C Metsulfuron-Methyl in Soil from an Oil Palm Plantation

Ismail BS, Eng OK, Tayeb MA

PLoS One, 2015;10(10):e0138170.
PMID: 26437264 DOI: 10.1371/journal.pone.0138170

Triazine-2-(14)C metsulfuron-methyl is a selective, systemic sulfonylurea herbicide. Degradation studies in soils are essential for the evaluation of the persistence of pesticides and their breakdown products. The purpose of the present study was to investigate the degradation of triazine-2-(14)C metsulfuron-methyl in soil under laboratory conditions. A High Performance Liquid Chromatograph (HPLC) equipped with an UV detector and an on-line radio-chemical detector, plus a Supelco Discovery column (250 x 4.6 mm, 5 μm), and PRP-1 column (305 x 7.0 mm, 10 μm) was used for the HPLC analysis. The radioactivity was determined by a Liquid Scintillation Counter (LSC) in scintillation fluid. The soil used was both sterilized and non-sterilized in order to observe the involvement of soil microbes. The estimated DT50 and DT90 values of metsulfuron-methyl in a non-sterile system were observed to be 13 and 44 days, whereas in sterilized soil, the DT50 and DT90 were 31 and 70 days, respectively. The principal degradation product after 60 days was CO2. The higher cumulative amount of (14)CO2 in (14)C-triazine in the non-sterilized soil compared to that in the sterile system suggests that biological degradation by soil micro-organisms significantly contributes to the dissipation of the compound. The major routes of degradation were O-demethylation, sulfonylurea bridge cleavage and the triazine "ring-opened."

Matched MeSH terms: Oxygen/metabolism
Fulltext Knockdown of Stromal Interaction Molecule 1 (STIM1) Suppresses Acute Myeloblastic Leukemia-M5 Cell Line Survival Through Inhibition of Reactive Oxygen Species Activities

Algariri ES, Mydin RBSMN, Moses EJ, Okekpa SI, Rahim NAA, Yusoff NM

Turk J Haematol, 2023 Feb 28;40(1):11-17.
PMID: 36404683 DOI: 10.4274/tjh.galenos.2022.2022.0246

OBJECTIVE: This study aimed to investigate the role of the stromal interaction molecule 1 (STIM1) gene in the survival of the acute myeloblastic leukemia (AML)-M5 cell line (THP-1).
MATERIALS AND METHODS: The STIM1 effect was assessed via dicersubstrate siRNA-mediated STIM1 knockdown. The effect of STIM1 knockdown on the expression of AKT and MAPK pathway-related genes and reactive oxygen species (ROS) generation-related genes was tested using real-time polymerase chain reaction. Cellular functions, including ROS generation, cell proliferation, and colony formation, were also evaluated following STIM1 knockdown.
RESULTS: The findings revealed that STIM1 knockdown reduced intracellular ROS levels via downregulation of NOX2 and PKC. These findings were associated with the downregulation of AKT, KRAS, MAPK, and CMYC. BCL2 was also downregulated, while BAX was upregulated following STIM1 knockdown. Furthermore, STIM1 knockdown reduced THP-1 cell proliferation and colony formation.
CONCLUSION: This study has demonstrated the role of STIM1 in promoting AML cell proliferation and survival through enhanced ROS generation and regulation of AKT/MAPK-related pathways. These findings may help establish STIM1 as a potential therapeutic target for AML treatment.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Fulltext Dominant phytoplankton groups as the major source of polyunsaturated fatty acids for hilsa (Tenualosa ilisha) in the Meghna estuary Bangladesh

Shaha DC, Hasan J, Kundu SR, Yusoff FM, Salam MA, Khan M, et al.

Sci Rep, 2022 Dec 05;12(1):20980.
PMID: 36470973 DOI: 10.1038/s41598-022-24500-2

The tropical estuarine ecosystem is fascinating for studying the dynamics of water quality and phytoplankton diversity due to its frequently changing hydrological conditions. Most importantly, phytoplankton is the main supplier of ω3 polyunsaturated fatty acids (PUFA) in the coastal food web for fish as they could not synthesize PUFA. This study evaluated seasonal variations of water quality parameters in the Meghna River estuary (MRE), explored how phytoplankton diversity changes according to hydro-chemical parameters, and identified the major phytoplankton groups as the main source of PUFA for hilsa fish. Ten water quality indicators including temperature, dissolved oxygen, pH, salinity, dissolved inorganic nitrogen (DIN = nitrate, nitrite, ammonia) and phosphorus, dissolved silica and chlorophyll-a were evaluated. In addition, phytoplankton diversity was assessed in the water and hilsa fish gut. Principal component analysis (PCA) was used to analyze the spatio-temporal changes in the water quality conditions, and the driving factors in the MRE. Four main components were extracted and explained 75.4% variability of water quality parameters. The most relevant driving factors were dissolved oxygen, salinity, temperature, and DIN (nitrate, nitrite and ammonia). These variabilities in physicochemical parameters and dissolved inorganic nutrients caused seasonal variations in two major groups of phytoplankton. Peak abundance of Chlorophyta (green algae) occurred in water in nutrient-rich environments (nitrogen and phosphorus) during the wet (36%) season, while Bacillariophyta (diatoms) were dominant during the dry (32%) season that depleted dissolved silica. Thus, the decrease of green algae and the increase of diatoms in the dry season indicated the potential link to seasonal changes of hydro-chemical parameters. The green algae (53.7%) were the dominant phytoplankton group in the hilsa gut content followed by diatoms (22.6%) and both are contributing as the major source of PUFAs for hilsa fish according to the electivity index as they contain the highest amounts of PUFAs (60 and 28% respectively).

Matched MeSH terms: Oxygen/analysis

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