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Fulltext Goniothalamin-induced oxidative stress, DNA damage and apoptosis via caspase-2 independent and Bcl-2 independent pathways in Jurkat T-cells

Inayat-Hussain SH, Chan KM, Rajab NF, Din LB, Chow SC, Kizilors A, et al.

Toxicol Lett, 2010 Mar 1;193(1):108-14.
PMID: 20026395 DOI: 10.1016/j.toxlet.2009.12.010

Goniothalamin (GTN) isolated from Goniothalamus sp. has been demonstrated to induce apoptosis in a variety of cancer cell lines including Jurkat T leukemia cells. However, the mechanism of GTN-induced apoptosis upstream of mitochondria is still poorly defined. In this study, GTN caused a decrease in GSH with an elevation of reactive oxygen species as early as 30 min and DNA damage as assessed by Comet assay. Analysis using topoisomerase II processing of supercoiled pBR 322 DNA showed that GTN caused DNA damage via a topoisomerase II-independent pathway suggesting that cellular oxidative stress may contribute to genotoxicity. A 12-fold increase of caspase-2 activity was observed in GTN-treated Jurkat cells after 4h treatment and this was confirmed using Western blotting. Although the caspase-2 inhibitor Z-VDVAD-FMK inhibited the proteolytic activity of caspase-2, apoptosis ensued confirming that caspase-2 activity was not crucial for GTN-induced apoptosis. However, GTN-induced apoptosis was completely abrogated by N-acetylcysteine further confirming the role of oxidative stress. Since cytochrome c release was observed as early as 1h without any appreciable change in Bcl-2 protein expression, we further investigated whether overexpression of Bcl-2 confers resistance in GTN-induced cytotoxicity. Using a panel of Jurkat Bcl-2 transfectants, GTN cytotoxicity was not abrogated in these cells. In conclusion, GTN induces DNA damage and oxidative stress resulting in apoptosis which is independent of both caspase-2 and Bcl-2.

Matched MeSH terms: Reactive Oxygen Species
Fulltext Anti-tumor effect of Ardisia crispa hexane fraction on 7, 12-dimethylbenz[α]anthracene-induced mouse skin papillomagenesis

Sulaiman H, Hamid RA, Ting YL, Othman F

J Cancer Res Ther, 2012 Jul-Sep;8(3):404-10.
PMID: 23174723 DOI: 10.4103/0973-1482.103521

CONTEXT: Ardisia crispa Thunb. A. DC (Myrsinaceae) or locally known as hen's eyes has been used in local folk medicine as a remedy in various illnesses. Previously, it has been reported to inhibit various inflammatory diseases. However, research done on this plant is still limited.
AIMS: In the present study, the hexane fraction of the A. crispa root (ACRH) was evaluated on the peri-initiation and promotion phases of skin carcinogenesis.
MATERIALS AND METHODS: This two-stage skin carcinogenesis was induced by a single topical application of 7,12-dimethylbenz(α)anthracene (DMBA) and promoted by repeated treatment with croton oil for 10 weeks in Imprinting Control Region (ICR) mice. Morphological observation would be conducted to measure tumor incidence, tumor burden, and tumor volume. Histological evaluation on the skin tissue would also be done.
RESULTS: The carcinogen control group exhibited 66.67% of tumor incidence. Although, in the ACRH-treated groups, at 30 mg/kg, the mice showed only 10% of tumor incidence with a significant reduction (P < 0.05) in the values of tumor burden and tumor volume of 2.00 and 0.52 mm(3), respectively. Furthermore, the result was significantly lower than that of the carcinogen and curcumin control. At 100 mg/kg, ACRH showed a comparable result to carcinogen control. On the contrary, at 300 mg/kg, ACRH exhibited 100% tumor incidence and showed a significant elevated (P < 0.05) value of tumor burden (3.80) and tumor volume (14.67 ± 2.48 mm(3)).
CONCLUSIONS: The present study thus demonstrates that the anti-tumor effect of the chemopreventive potential of ACRH is at a lower dosage (30 mg/kg bwt) in both the initiating and promotion period, yet it exhibits a promoting effect at a higher dosage (300 mg/kg bwt).

Matched MeSH terms: Reactive Oxygen Species
Fulltext PI3K/Akt activity has variable cell-specific effects on expression of HIF target genes, CA9 and VEGF, in human cancer cell lines

Shafee N, Kaluz S, Ru N, Stanbridge EJ

Cancer Lett, 2009 Sep 8;282(1):109-15.
PMID: 19342157 DOI: 10.1016/j.canlet.2009.03.004

The phosphatidylinositol 3-kinase/Akt (PI3K) pathway regulates hypoxia-inducible factor (HIF) activity. Higher expression of HIF-1alpha and carbonic anhydrase IX (CAIX), a hypoxia-inducible gene, in HT10806TG fibrosarcoma cells (mutant N-ras allele), compared to derivative MCH603 cells (deleted mutant N-ras allele), correlated with increased PI3K activity. Constitutive activation of the PI3K pathway in MCH603/PI3K(act) cells increased HIF-1alpha but, surprisingly, decreased CAIX levels. The cell-type specific inhibitory effect on CAIX was confirmed at the transcriptional level whereas epigenetic modifications of CA9 were ruled out. In summary, our data do not substantiate the generalization that PI3K upregulation leads to increased HIF activity.

Matched MeSH terms: Oxygen Consumption
Fulltext Hyperhomocysteinemia causes ER stress and impaired autophagy that is reversed by Vitamin B supplementation

Tripathi M, Zhang CW, Singh BK, Sinha RA, Moe KT, DeSilva DA, et al.

Cell Death Dis, 2016 12 08;7(12):e2513.
PMID: 27929536 DOI: 10.1038/cddis.2016.374

Hyperhomocysteinemia (HHcy) is a well-known risk factor for stroke; however, its underlying molecular mechanism remains unclear. Using both mouse and cell culture models, we have provided evidence that impairment of autophagy has a central role in HHcy-induced cellular injury in the mouse brain. We observed accumulation of LC3B-II and p62 that was associated with increased MTOR signaling in human and mouse primary astrocyte cell cultures as well as a diet-induced mouse model of HHcy, HHcy decreased lysosomal membrane protein LAMP2, vacuolar ATPase (ATP6V0A2), and protease cathepsin D, suggesting that lysosomal dysfunction also contributed to the autophagic defect. Moreover, HHcy increased unfolded protein response. Interestingly, Vitamin B supplementation restored autophagic flux, alleviated ER stress, and reversed lysosomal dysfunction due to HHCy. Furthermore, the autophagy inducer, rapamycin was able to relieve ER stress and reverse lysosomal dysfunction caused by HHcy in vitro. Inhibition of autophagy by HHcy exacerbated cellular injury during oxygen and glucose deprivation and reperfusion (OGD/R), and oxidative stress. These effects were prevented by Vitamin B co-treatment, suggesting that it may be helpful in relieving detrimental effects of HHcy in ischemia/reperfusion or oxidative stress. Collectively, these findings show that Vitamin B therapy can reverse defects in cellular autophagy and ER stress due to HHcy; and thus may be a potential treatment to reduce ischemic damage caused by stroke in patients with HHcy.

Matched MeSH terms: Oxygen
Pathological vicissitudes and oxidative stress enzyme responses in mice experimentally infected with reptarenavirus (isolate UPM/MY01)

Abba Y, Hassim H, Hamzah H, Ibrahim OE, Mohd Lila MA, Noordin MM

Microb Pathog, 2017 Mar;104:17-27.
PMID: 28062291 DOI: 10.1016/j.micpath.2017.01.003

Boid inclusion body disease (BIBD) is a viral disease of boid snakes believed to be caused by reptarenavirus belonging to the family Arenaviridae. Unlike most mammalian arenaviruses, the reservoir host for reptarenavirus is still unknown. In this study, the pathological responses were evaluated in a mouse model for a period of 28 days. Blood and tissue samples (lung, liver, spleen, heart, kidney and brain) were collected for evaluation of hematology, biochemistry, histopathology and oxidative enzyme levels at six time points (1, 3, 7, 14, 21 and 28 days), after viral infection (2.0 × 10(6) pfu/mL) in the infected and normal saline in the control groups. An initial increase (p

Matched MeSH terms: Reactive Oxygen Species
Fulltext The interplay between metabolic alterations, diastolic strain rate and exercise capacity in mild heart failure with preserved ejection fraction: a cardiovascular magnetic resonance study

Mahmod M, Pal N, Rayner J, Holloway C, Raman B, Dass S, et al.

J Cardiovasc Magn Reson, 2018 12 24;20(1):88.
PMID: 30580760 DOI: 10.1186/s12968-018-0511-6

BACKGROUND: Heart failure (HF) is characterized by altered myocardial substrate metabolism which can lead to myocardial triglyceride accumulation (steatosis) and lipotoxicity. However its role in mild HF with preserved ejection fraction (HFpEF) is uncertain. We measured myocardial triglyceride content (MTG) in HFpEF and assessed its relationships with diastolic function and exercise capacity.
METHODS: Twenty seven HFpEF (clinical features of HF, left ventricular EF >50%, evidence of mild diastolic dysfunction and evidence of exercise limitation as assessed by cardiopulmonary exercise test) and 14 controls underwent 1H-cardiovascular magnetic resonance spectroscopy (1H-CMRS) to measure MTG (lipid/water, %), 31P-CMRS to measure myocardial energetics (phosphocreatine-to-adenosine triphosphate - PCr/ATP) and feature-tracking cardiovascular magnetic resonance (CMR) imaging for diastolic strain rate.
RESULTS: When compared to controls, HFpEF had 2.3 fold higher in MTG (1.45 ± 0.25% vs. 0.64 ± 0.16%, p = 0.009) and reduced PCr/ATP (1.60 ± 0.09 vs. 2.00 ± 0.10, p = 0.005). HFpEF had significantly reduced diastolic strain rate and maximal oxygen consumption (VO2 max), which both correlated significantly with elevated MTG and reduced PCr/ATP. On multivariate analyses, MTG was independently associated with diastolic strain rate while diastolic strain rate was independently associated with VO2 max.
CONCLUSIONS: Myocardial steatosis is pronounced in mild HFpEF, and is independently associated with impaired diastolic strain rate which is itself related to exercise capacity. Steatosis may adversely affect exercise capacity by indirect effect occurring via impairment in diastolic function. As such, myocardial triglyceride may become a potential therapeutic target to treat the increasing number of patients with HFpEF.

Matched MeSH terms: Oxygen Consumption
Annona muricata leaves induce G₁ cell cycle arrest and apoptosis through mitochondria-mediated pathway in human HCT-116 and HT-29 colon cancer cells

Zorofchian Moghadamtousi S, Karimian H, Rouhollahi E, Paydar M, Fadaeinasab M, Abdul Kadir H

J Ethnopharmacol, 2014 Oct 28;156:277-89.
PMID: 25195082 DOI: 10.1016/j.jep.2014.08.011

ETHNOPHARMACOLOGICAL RELEVANCE: Annona muricata known as "the cancer killer" has been widely used in the traditional medicine for the treatment of cancer and tumors. The purpose of this study is to investigate the anticancer properties of ethyl acetate extract of Annona muricata leaves (EEAM) on HT-29 and HCT-116 colon cancer cells and the underlying mechanisms.
MATERIALS AND METHODS: The effect of EEAM on the cell proliferation of HT-29 and HCT-116 cells was analyzed by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium) assay. High content screening system (HCS) was applied to investigate the cell membrane permeability, mitochondrial membrane potential (MMP), nuclear condensation and cytochrome c translocation from mitochondria to cytosol. Reactive oxygen species (ROS) formation, lactate dehydrogenase (LDH) release and activation of caspase-3/7, -8 and -9 were measured while treatment. Flow cytometric analysis was used to determine the cell cycle distribution and phosphatidylserine externalization. The protein expression of Bax and Bcl-2 was determined using immunofluorescence analysis. In addition, the potential of EEAM to suppress the migration and invasion of colon cancer cells was also examined.
RESULTS: EEAM exerted significant cytotoxic effects on HCT-116 and HT-29 cells as determined by MTT and LDH assays. After 24 h treatment, EEAM exhibited the IC₅₀ value of 11.43 ± 1.87 µg/ml and 8.98 ± 1.24 µg/ml against HT-29 and HCT-116 cells, respectively. Flow cytometric analysis demonstrated the cell cycle arrest at G1 phase and phosphatidylserine externalization confirming the induction of apoptosis. EEAM treatment caused excessive accumulation of ROS followed by disruption of MMP, cytochrome c leakage and activation of the initiator and executioner caspases in both colon cancer cells. Immunofluorescence analysis depicted the up-regulation of Bax and down-regulation of Bcl-2 proteins while treated with EEAM. Furthermore, EEAM conspicuously blocked the migration and invasion of HT-29 and HCT-116 cells.
CONCLUSIONS: These findings provide a scientific basis for the use of A. muricata leaves in the treatment of cancer, although further in vivo studies are still required.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Fulltext Subditine, a new monoterpenoid indole alkaloid from bark of Nauclea subdita (Korth.) Steud. induces apoptosis in human prostate cancer cells

Liew SY, Looi CY, Paydar M, Cheah FK, Leong KH, Wong WF, et al.

PLoS One, 2014;9(2):e87286.
PMID: 24551054 DOI: 10.1371/journal.pone.0087286

In this study, a new apoptotic monoterpenoid indole alkaloid, subditine (1), and four known compounds were isolated from the bark of Nauclea subdita. Complete (1)H- and (13)C- NMR data of the new compound were reported. The structures of isolated compounds were elucidated with various spectroscopic methods such as 1D- and 2D- NMR, IR, UV and LCMS. All five compounds were screened for cytotoxic activities on LNCaP and PC-3 human prostate cancer cell-lines. Among the five compounds, the new alkaloid, subditine (1), demonstrated the most potent cell growth inhibition activity and selective against LNCaP with an IC50 of 12.24±0.19 µM and PC-3 with an IC50 of 13.97±0.32 µM, compared to RWPE human normal epithelial cell line (IC50 = 30.48±0.08 µM). Subditine (1) treatment induced apoptosis in LNCaP and PC-3 as evidenced by increased cell permeability, disruption of cytoskeletal structures and increased nuclear fragmentation. In addition, subditine (1) enhanced intracellular reactive oxygen species (ROS) production, as reflected by increased expression of glutathione reductase (GR) to scavenge damaging free radicals in both prostate cancer cell-lines. Excessive ROS could lead to disruption of mitochondrial membrane potential (MMP), release of cytochrome c and subsequent caspase 9, 3/7 activation. Further Western blot analyses showed subditine (1) induced down-regulation of Bcl-2 and Bcl-xl expression, whereas p53 was up-regulated in LNCaP (p53-wild-type), but not in PC-3 (p53-null). Overall, our data demonstrated that the new compound subditine (1) exerts anti-proliferative effect on LNCaP and PC-3 human prostate cancer cells through induction of apoptosis.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Nicotinamide supplementation protects gestational diabetic rats by reducing oxidative stress and enhancing immune responses

John CM, Ramasamy R, Al Naqeeb G, Al-Nuaimi AH, Adam A

Curr Med Chem, 2012;19(30):5181-6.
PMID: 23237188

Gestational diabetes (GD) is a common complication during pregnancy. Metabolic changes in GD affect fetal development and fetal glucose homeostasis. The present study utilized a rat model of GD to evaluate the effects of nicotinamide on diabetic parameters; antioxidant gene expression viz, superoxide dismutase (SOD) and catalase (CAT); reactive oxygen species (ROS) production by neutrophils and enhancement of lymphocyte mediated immune response. Nicotinamide (50, 100 and 200 mg/kg) was orally supplemented to gestational diabetic rats from days 6 through 20 of gestation. After GD induction, the control group had elevated glucose and reduced insulin while nicotinamide (100 & 200 mg/kg) supplementation reversed these changes. The same doses of nicotinamide upregulated mRNA expressions of SOD and CAT genes in liver but reduced the oxidative burst activity of neutrophils in response to phorbol myristate acetate (PMA), N-formyl-methionyl-leucyl-phenylalanine (FMLP) or E. coli activation. Nicotinamide (100 & 200 mg/kg) supplementation also increased expression of activated T helper (CD4+CD25+) cells and induced proliferation of splenocytes. These findings provide evidence for utilizing nicotinamide as supplement or adjunct to support existing therapeutic agents for gestational diabetes and in pregnant individuals with weakened immune systems.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Dentatin isolated from Clausena excavata induces apoptosis in MCF-7 cells through the intrinsic pathway with involvement of NF-κB signalling and G0/G1 cell cycle arrest: a bioassay-guided approach

Arbab IA, Abdul AB, Sukari MA, Abdullah R, Syam S, Kamalidehghan B, et al.

J Ethnopharmacol, 2013 Jan 9;145(1):343-54.
PMID: 23178663 DOI: 10.1016/j.jep.2012.11.020

Clausena excavata Burm. f. has been used in folk medicines in eastern Thailand for the treatment of cancer.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Fulltext Novel Semi-Synthetic Cu (II)-Cardamonin Complex Exerts Potent Anticancer Activity against Triple-Negative Breast and Pancreatic Cancer Cells via Inhibition of the Akt Signaling Pathway

Hossan MS, Break MKB, Bradshaw TD, Collins HM, Wiart C, Khoo TJ, et al.

Molecules, 2021 Apr 09;26(8).
PMID: 33918814 DOI: 10.3390/molecules26082166

Cardamonin is a polyphenolic natural product that has been shown to possess cytotoxic activity against a variety of cancer cell lines. We previously reported the semi-synthesis of a novel Cu (II)-cardamonin complex (19) that demonstrated potent antitumour activity. In this study, we further investigated the bioactivity of 19 against MDA-MB-468 and PANC-1 cancer cells in an attempt to discover an effective treatment for triple-negative breast cancer (TNBC) and pancreatic cancer, respectively. Results revealed that 19 abolished the formation of MDA-MB-468 and PANC-1 colonies, exerted growth-inhibitory activity, and inhibited cancer cell migration. Further mechanistic studies showed that 19 induced DNA damage resulting in gap 2 (G2)/mitosis (M) phase arrest and microtubule network disruption. Moreover, 19 generated reactive oxygen species (ROS) that may contribute to induction of apoptosis, corroborated by activation of caspase-3/7, PARP cleavage, and downregulation of Mcl-1. Complex 19 also decreased the expression levels of p-Akt and p-4EBP1, which indicates that the compound exerts its activity, at least in part, via inhibition of Akt signalling. Furthermore, 19 decreased the expression of c-Myc in PANC-1 cells only, which suggests that it may exert its bioactivity via multiple mechanisms of action. These results demonstrate the potential of 19 as a therapeutic agent for TNBC and pancreatic cancer.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Fulltext Artonin E Induces Apoptosis via Mitochondrial Dysregulation in SKOV-3 Ovarian Cancer Cells

Rahman MA, Ramli F, Karimian H, Dehghan F, Nordin N, Ali HM, et al.

PLoS One, 2016;11(3):e0151466.
PMID: 27019365 DOI: 10.1371/journal.pone.0151466

Artonin E is a prenylated flavonoid isolated from the stem bark of Artocarpus elasticus Reinw.(Moraceae). This study aimed to investigate the apoptotic mechanisms induced by artonin E in a metastatic human ovarian cancer cell line SKOV-3 in vitro. MTT assay, clonogenic assay, acridine orange and propidium iodide double staining, cell cycle and annexin V analyses were performed to explore the mode of artonin E-induced cell death at different time points. DNA laddering, activation of caspases-3, -8, and -9, multi-parametric cytotoxicity-3 analysis by high-content screening, measurement of reactive oxygen species generation, and Western blot were employed to study the pathways involved in the apoptosis. MTT results showed that artonin E inhibited the growth of SKOV-3 cells, with IC50 values of 6.5±0.5 μg/mL after 72 h treatment, and showed less toxicity toward a normal human ovarian cell line T1074, with IC50 value of 32.5±0.5 μg/mL. Results showed that artonin E induced apoptosis and cell cycle arrest at the S phase. This compound also promoted the activation of caspases-3, -8, and -9. Further investigation into the depletion of mitochondrial membrane potential and release of cytochrome c revealed that artonin E treatment induced apoptosis via regulation of the expression of pro-survival and pro-apoptotic Bcl-2 family members. The expression levels of survivin and HSP70 proteins were also down regulated in SKOV-3 cells treated with artonin E. We propose that artonin E induced an antiproliferative effect that led to S phase cell cycle arrest and apoptosis through dysregulation of mitochondrial pathways, particularly the pro- and anti-apoptosis signaling pathways.

Matched MeSH terms: Reactive Oxygen Species/metabolism
Fulltext Antioxidant activity of methanol extracts of different parts of Lantana camara

Mahdi-Pour B, Jothy SL, Latha LY, Chen Y, Sasidharan S

Asian Pac J Trop Biomed, 2012 Dec;2(12):960-5.
PMID: 23593576 DOI: 10.1016/S2221-1691(13)60007-6

To investigate the antioxidant activity of methanolic extracts of Lantana camara (L. camara) various parts and the determination of their total phenolics content.

Matched MeSH terms: Reactive Oxygen Species
Spatial aspects of surface water quality in the Jakara Basin, Nigeria using chemometric analysis

Mustapha A, Aris AZ

J Environ Sci Health A Tox Hazard Subst Environ Eng, 2012;47(10):1455-65.
PMID: 22571534 DOI: 10.1080/10934529.2012.673305

Multivariate statistical techniques such as hierarchical Agglomerated cluster analysis (HACA), discriminant analysis (DA), principal component analysis (PCA), and factor analysis (FA) were applied to identify the spatial variation and pollution sources of Jakara River, Kano, Nigeria. Thirty surface water samples were collected: 23 along Getsi River and 7 along the main channel of River Jakara. Twenty-three water quality parameters, namely pH, temperature, turbidity, electrical conductivity (EC), dissolved oxygen (DO), 5-day biochemical oxygen demand (BOD(5)), Faecal coliform, total solids (TS), nitrates (NO(3)(-)), phosphates (PO(4)(3-)), cobalt (Co), iron (Fe), nickel (Ni), manganese (Mn), copper (Cu), sodium (Na), potassium (K), mercury (Hg), chromium (Cr), cadmium (Cd), lead (Pb), magnesium (Mg), and calcium(Ca) were analysed. HACA grouped the sampling points into three clusters based on the similarities of river water quality characteristics: industrial, domestic, and agricultural water pollution sources. Forward and backward DA effectively discriminated 5 and 15 water quality variables, respectively, each assigned with 100% correctness from the original 23 variables. PCA and FA were used to investigate the origin of each water quality parameter due to various land use activities, 7 principal components were obtained with 77.5% total variance, and in addition PCA identified 3 latent pollution sources to support HACA. From this study, one can conclude that the application of multivariate techniques derives meaningful information from water quality data.

Matched MeSH terms: Biological Oxygen Demand Analysis
Characterization of aerobic granular sludge treating high strength agro-based wastewater at different volumetric loadings

Abdullah N, Yuzir A, Curtis TP, Yahya A, Ujang Z

Bioresour Technol, 2013 Jan;127:181-7.
PMID: 23131639 DOI: 10.1016/j.biortech.2012.09.047

Understanding the relationship between microbial community and mechanism of aerobic granulation could enable wider applications of granules for high-strength wastewater treatment. The majority of granulation studies principally determine the engineering aspects of granules formation with little emphasis on the microbial diversity. In this study, three identical reactors namely R1, R2 and R3 were operated using POME at volumetric loadings of 1.5, 2.5 and 3.5 kg COD m(-3) d(-1), respectively. Aeration was provided at a volumetric flow rate of 2.5 cms(-1). Aerobic granules were successfully developed in R2 and R3 while bioflocs dominated R1 until the end of experiments. Fractal dimension (D(f)) averaged at 1.90 suggesting good compactness of granules. The PCR-DGGE results indicated microbial evolutionary shift throughout granulation despite different operating OLRs based on decreased Raup and Crick similarity indices upon mature granule formation. The characteristics of aerobic granules treating high strength agro-based wastewater are determined at different volumetric loadings.

Matched MeSH terms: Biological Oxygen Demand Analysis
The influenced of PAC, zeolite, and Moringa oleifera as biofouling reducer (BFR) on hybrid membrane bioreactor of palm oil mill effluent (POME)

Damayanti A, Ujang Z, Salim MR

Bioresour Technol, 2011 Mar;102(6):4341-6.
PMID: 21251818 DOI: 10.1016/j.biortech.2010.12.061

The main objective of this work was to determine the effectiveness of various biofouling reducers (BFRs) to operational condition in hybrid membrane bioreactor (MBR) of palm oil mill effluent (POME). A series of tests involving three bench scale (100 L) hybrid MBR were operated at sludge retention times (SRTs) of 30 days with biofouling reducer (BFR). Three different biofouling reducers (BFRs) were powdered actived carbon (PAC), zeolite (Ze), and Moringa oleifera (Mo) with doses of 4, 8 and 12 g L(-1) respectively were used. Short-term filtration trials and critical flux tests were conducted. Results showed that, all BFRs successfully removed soluble microbial products (SMP), for PAC, Ze, and Mo at 58%, 42%, and 48%, respectively. At their optimum dosages, PAC provided above 70% reductions and 85% in fouling rates during the short-term filtration and critical flux tests.

Matched MeSH terms: Biological Oxygen Demand Analysis
Reduction of DNA damage in older healthy adults by Tri E Tocotrienol supplementation

Chin SF, Hamid NA, Latiff AA, Zakaria Z, Mazlan M, Yusof YA, et al.

Nutrition, 2008 Jan;24(1):1-10.
PMID: 17884341

The free radical theory of aging (FRTA) suggests that free radicals are the leading cause of deteriorating physiologic function during senescence. Free radicals attack cellular structures or molecules such as DNA resulting in various modifications to the DNA structures. Accumulation of unrepaired DNA contributes to a variety of disorders associated with the aging process.

Matched MeSH terms: Reactive Oxygen Species
Effect of Mecoprop (RS)-MCPP on the biological treatment of synthetic wastewater in an anaerobic membrane bioreactor

Yuzir A, Abdullah N, Chelliapan S, Sallis P

Bioresour Technol, 2013 Apr;133:158-65.
PMID: 23422308 DOI: 10.1016/j.biortech.2013.01.086

The effects of Mecoprop (RS)-MCPP were investigated in an anaerobic membrane bioreactor (AnMBr) fed with synthetic wastewater containing stepwise increases in Mecoprop concentration, 5-200 mg L(-1) over 240 days. Effects were observed in terms of soluble chemical oxygen demand (COD) removal efficiency, volatile fatty acid (VFA) production, and methane yield. Soluble COD removal efficiency was stable at Mecoprop concentrations below 200 (±3) mg L(-1), with an average of 98 (±0.7)% removal. However, at 200 (±3) mg L(-1) Mecoprop, the COD removal efficiency decreased gradually to 94 (±1.5)%. At 5 mg L(-1) Mecoprop, acetic and propionic acid concentrations increased by 60% and 160%, respectively. In contrast, when Mecoprop was increased to 200 (±3) mg L(-1), the formation and degradation of acetate was unaffected by the higher Mecoprop concentration, acetate remaining below 35 mg L(-1). Increases in the Mecoprop specific utilization rate were observed as Mecoprop was increased stepwise between 5 and 200 mg L(-1).

Matched MeSH terms: Biological Oxygen Demand Analysis
Pathologic activity of Plasmodium berghei prevented but not reversed by dexamethasone

Franz DR, Lim TS, Baze WB, Arimbalam S, Lee M, Lewis GE

Am J Trop Med Hyg, 1988 Mar;38(2):249-54.
PMID: 3281490

Dexamethasone has recently been shown to block the production of cachectin (implicated in the pathogenesis of cerebral malaria) if administered prior to endotoxin induction of mouse macrophages. Using the hamster cheek pouch-cerebral malaria model, we tested the hypothesis that dexamethasone is effective as a therapeutic agent in severe malaria if given before some yet undefined trigger point in the disease. Infected hamsters were treated with dexamethasone (0.7 mg/kg) daily on days 7-12, 4-12, or 1-12 post-challenge. When treatment was started on day 1, whole body oxygen consumption (used as a measure of erythrocyte transport to sites of diffusion) on day 12 was greater than (P less than 0.05) that of infected control animals, though the degree of anemia was no different in treated and untreated groups. Furthermore, treatment produced a reduction in monocyte accumulation, capillary malfunction, and monocyte/red blood cell aggregate formation observable in the cheek pouch in vivo and a similar reduction in monocyte presence, capillary pathologic change, and multifocal hemorrhage in the brain on postmortem. These data suggest that mediator(s), whose production can be blocked by pretreatment with dexamethasone, are involved in the pathogenesis of disease leading to death of the Plasmodium berghei infected hamster.

Matched MeSH terms: Oxygen Consumption
Fulltext Natural Xanthones and Skin Inflammatory Diseases: Multitargeting Mechanisms of Action and Potential Application

Gunter NV, Teh SS, Lim YM, Mah SH

Front Pharmacol, 2020;11:594202.
PMID: 33424605 DOI: 10.3389/fphar.2020.594202

The pathogenesis of skin inflammatory diseases such as atopic dermatitis, acne, psoriasis, and skin cancers generally involve the generation of oxidative stress and chronic inflammation. Exposure of the skin to external aggressors such as ultraviolet (UV) radiation and xenobiotics induces the generation of reactive oxygen species (ROS) which subsequently activates immune responses and causes immunological aberrations. Hence, antioxidant and anti-inflammatory agents were considered to be potential compounds to treat skin inflammatory diseases. A prime example of such compounds is xanthone (xanthene-9-one), a class of natural compounds that possess a wide range of biological activities including antioxidant, anti-inflammatory, antimicrobial, cytotoxic, and chemotherapeutic effects. Many studies reported various mechanisms of action by xanthones for the treatment of skin inflammatory diseases. These mechanisms of action commonly involve the modulation of various pro-inflammatory cytokines such as interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor α (TNF-α), as well as anti-inflammatory cytokines such as IL-10. Other mechanisms of action include the regulation of NF-κB and MAPK signaling pathways, besides immune cell recruitment via modulation of chemokines, activation, and infiltration. Moreover, disease-specific activity contributed by xanthones, such as antibacterial action against Propionibacterium acnes and Staphylococcus epidermidis for acne treatment, and numerous cytotoxic mechanisms involving pro-apoptotic and anti-metastatic effects for skin cancer treatment have been extensively elucidated. Furthermore, xanthones have been reported to modulate pathways responsible for mediating oxidative stress and inflammation such as PPAR, nuclear factor erythroid 2-related factor and prostaglandin cascades. These pathways were also implicated in skin inflammatory diseases. Xanthones including the prenylated α-mangostin (2) and γ-mangostin (3), glucosylated mangiferin (4) and the caged xanthone gambogic acid (8) are potential lead compounds to be further developed into pharmaceutical agents for the treatment of skin inflammatory diseases. Future studies on the structure-activity relationships, molecular mechanisms, and applications of xanthones for the treatment of skin inflammatory diseases are thus highly recommended.

Matched MeSH terms: Reactive Oxygen Species

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