MyMedR

Displaying publications 41 - 60 of 165 in total

Abstract:

Sort:

Fulltext Residual quantification and oxidative stress induced by malachite green after subacute and sublethal exposure in red tilapia

Kwan PP, Banerjee S, Shariff M, Yusoff FM

Vet World, 2019 Sep;12(9):1416-1421.
PMID: 31749575 DOI: 10.14202/vetworld.2019.1416-1421

Background and Aim: Malachite green (MG) is an effective antiparasitic and antifungal chemical for treatment of fish. However, MG is reported to be a potential carcinogen. Yet, it is widely used in aquaculture despite its prohibition for use in food-producing animals by the EU and USFDA. The present study quantified MG residues and evaluated the oxidative stress in red tilapia when exposed to subacute and sublethal concentrations of MG.
Materials and Methods: Red tilapia exposed to subacute (0.105 mg/L for 20 days) and sublethal (0.053 mg/L for 60 days) concentrations were evaluated for total plasma protein, total immunoglobulin, nitroblue tetrazolium activity, malondialdehyde, reduced glutathione (GSH), and catalase (CAT) activity levels. The residues of MG and leuco-MG (LMG) were also quantified in the fish muscles using liquid chromatography-tandem mass spectrometry.
Results: Fish exposed to subacute concentration showed higher CAT on day 10 in the liver and days 5 and 15 in the spleen, whereas in fish exposed to the sublethal concentration, higher levels of GSH were observed on day 1 in the kidney and day 50 in the spleen. Fish muscle was able to accumulate the sum of MG and LMG of 108.04 µg/kg for subacute (day 20) and 82.68 µg/kg for sublethal (day 60).
Conclusion: This study showed that red tilapia was able to adapt to the stress caused by exposure to MG at sublethal concentration.

Matched MeSH terms: Catalase
Fulltext Alpinia zerumbet (Pers.): Food and Medicinal Plant with Potential In Vitro and In Vivo Anti-Cancer Activities

Zahra MH, Salem TAR, El-Aarag B, Yosri N, El-Ghlban S, Zaki K, et al.

Molecules, 2019 Jul 08;24(13).
PMID: 31288458 DOI: 10.3390/molecules24132495

BACKGROUND/AIM: Plants play an important role in anti-cancer drug discovery, therefore, the current study aimed to evaluate the biological activity of Alpinia zerumbet (A. zerumbet) flowers.
METHODS: The phytochemical and biological criteria of A. zerumbet were in vitro investigated as well as in mouse xenograft model.
RESULTS: A. zerumbet extracts, specially CH2Cl2 and MeOH extracts, exhibited the highest potent anti-tumor activity against Ehrlich ascites carcinoma (EAC) cells. The most active CH2Cl2 extract was subjected to bioassay-guided fractionation leading to isolatation of the naturally occurring 5,6-dehydrokawain (DK) which was characterized by IR, MS, 1H-NMR and 13C-NMR. A. zerumbet extracts, specially MeOH and CH2Cl2 extracts, exhibited significant inhibitory activity towards tumor volume (TV). Furthermore, A. zerumbet extracts declined the high level of malonaldehyde (MDA) as well as elevated the levels of superoxide dismutase (SOD) and catalase (CAT) in liver tissue homogenate. Moreover, DK showed anti-proliferative action on different human cancer cell lines. The recorded IC50 values against breast carcinoma (MCF-7), liver carcinoma (Hep-G2) and larynx carcinoma cells (HEP-2) were 3.08, 6.8, and 8.7 µg/mL, respectively.
CONCLUSION: Taken together, these findings open the door for further investigations in order to explore the potential medicinal properties of A. zerumbet.

Matched MeSH terms: Catalase/metabolism
Effects of formulation development methods on the stability of model protein pharmaceuticals embedded in solid lipid matrices

Tabbassum M, Zeeshan F

Pharm Dev Technol, 2019 Jun;24(5):649-662.
PMID: 30474456 DOI: 10.1080/10837450.2018.1551902

This study was conducted to investigate the influence of formulation development methods on the stability (secondary structure, aggregation, and biological activity) of protein drugs embedded in lipid matrices. Catalase, horseradish peroxidase, and α-chymotrypsin were employed as model proteins, while Precirol® AT05 (glyceryl palmitostearate) was used as lipid matrix. Protein-loaded lipid matrices were prepared using melting and mixing and wet granulation methods. Attenuated total reflectance Fourier transform infrared (ATR FT-IR) spectroscopy, size exclusion chromatography (SEC) and biological activity analyses were performed. ATR FT-IR analysis indicated significant interference of the lipid with the protein amide-I band, which was eliminated using spectral subtraction. Wet granulation method induced more changes in protein secondary structure compared to melting and mixing method. SEC analysis gave evidence of protein aggregation for catalase upon adopting the wet granulation method. The biological activity of catalase was found to reduce significantly than other two proteins upon using wet granulation method, which might be ascribed to both secondary structure alterations and the formation of aggregates. Horseradish peroxidase and α-chymotrypsin did not form any soluble aggregates. In conclusion, melting and mixing method emerged as a better incorporation method compared to wet granulation because of better stability shown by the formulated proteins.

Matched MeSH terms: Catalase/administration & dosage; Catalase/chemistry
Protective effect of daidzein against streptozotocin-induced Alzheimer's disease via improving cognitive dysfunction and oxidative stress in rat model

Wei J, Yang F, Gong C, Shi X, Wang G

J Biochem Mol Toxicol, 2019 Jun;33(6):e22319.
PMID: 30897277 DOI: 10.1002/jbt.22319

Oxidative stress is performing an essential role in developing Alzheimer's disease (AD), and age-related disorder and other neurodegenerative diseases. In existing research, we have aimed at investigating the daidzein (4',7-dihydroxyisoflavone) effect (10 and 20 mg/kg of body weight), as a free radical scavenger and antioxidant in streptozotocin (STZ) infused AD in rat model. Daidzein treatment led to significant improvement in intracerebroventricular-streptozotocin (ICV-STZ)-induced memory and learning impairments that was evaluated by Morris water maze test and spontaneous locomotor activity. It significantly restored the alterations in malondialdehyde, catalase, superoxide dismutase, and reduced glutathione levels. In addition, histopathological observations in cerebral cortex and hippocampal areas confirmed the neuroprotective effect of daidzein. These outcomes provide experimental proof showing preventive effect of daidzein on memory, learning dysfunction and oxidative stress in case of ICV-STZ rats. In conclusion, daidzein offers a potential treatment module for various neurodegenerative disorders with regard to mental deficits like AD.

Matched MeSH terms: Catalase
Intraocular pressure-lowering effects of imidazo[1,2-a]- and pyrimido[1,2-a]benzimidazole compounds in rats with dexamethasone-induced ocular hypertension

Marcus AJ, Iezhitsa I, Agarwal R, Vassiliev P, Spasov A, Zhukovskaya O, et al.

Eur J Pharmacol, 2019 May 05;850:75-87.
PMID: 30716317 DOI: 10.1016/j.ejphar.2019.01.059

Ocular hypertension is believed to be involved in the etiology of primary open-angle glaucoma. Although many pharmaceutical agents have been shown to be effective for the reduction of intraocular pressure (IOP), a significant opportunity to improve glaucoma treatments remains. Thus, the aims of the present study were: (1) to evaluate the IOP-lowering effect of four compounds RU-551, RU-555, RU-839 (pyrimido[1,2-a]benzimidazole), and RU-615 (imidazo[1,2-a]benzimidazole) on steroid-induced ocular hypertension in rats after single drop and chronic applications; and (2) to test in silico and in vitro conventional rho-associated kinase (ROCK) inhibitory activity of the selected compound. This study demonstrated that RU-551, RU-555, RU-839, and RU-615 significantly reduced IOP in Sprague Dawley rats with dexamethasone (DEXA) induced ocular hypertension after single drop administration (0.1%), however RU-615 showed the best IOP lowering effect as indicated by maximum IOP reduction of 22.32% from baseline. Repeated dose topical application of RU-615 caused sustained reduction of IOP from baseline throughout the 3 weeks of treatment with maximum IOP reduction of 30.31% on day 15. This study also showed that the steroid-induced increase in IOP is associated with increased retinal oxidative stress and significant retinal ganglion cells (RGCs) loss. Prolonged treatment with RU-615 over 3 weeks results in normalization of IOP in DEXA-treated rats with partial restoration of retinal antioxidant status (catalase, glutathione and superoxide dismutase) and subsequent protective effect against RGC loss. Thus, IOP lowering activity of RU-615 together with antioxidant properties might be the factors that contribute to prevention of further RGC loss. In vitro part of this study explored the ROCK inhibitory activity of RU-615 using dexamethasone-treated human trabecular meshwork cells as a possible mechanism of action of its IOP lowering activity. However, this study didn't show conventional ROCK inhibition by RU-615 which was later confirmed by in silico consensus prediction. Therefore, in the future studies it is important to identify the upstream target receptors for RU-615 and then delineate the involved intracellular signalling pathways which are likely to be other than ROCK inhibition.

Matched MeSH terms: Catalase
A standardised Andrographis paniculata Burm. Nees aqueous extract prevents Lipopolysaccharide-induced cognitive deficits through suppression of inflammatory cytokines and oxidative stress mediators

Sani D, Khatab NIO, Kirby BP, Yong A, Hasan S, Basri H, et al.

J Adv Res, 2019 Mar;16:87-97.
PMID: 30899592 DOI: 10.1016/j.jare.2018.11.005

Substantial evidence has shown that most cases of memory impairment are associated with increased neuroinflammation and oxidative stress. In this study, the potential of a standardised Andrographis paniculata aqueous extract (APAE) to reverse neuroinflammation and cognitive impairment induced by lipopolysaccharide (LPS) was examined in vivo. Rats were treated with APAE (50, 100, 200, and 400 mg·kg-1, p.o.) for 7 consecutive days prior to LPS (1 mg·kg-1, i.p.)-induced neuroinflammation and cognitive impairment. Spatial learning and memory were evaluated using the Morris water maze (MWM) test, while neuroinflammation and oxidative stress were assessed through the measurement of specific mediators, namely, tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-1β, superoxide dismutase (SOD), catalase (CAT), antioxidant glutathione (GSH), reactive oxygen species (ROS), and thiobarbituric acid reactive substance (TBARS). Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were also evaluated. LPS caused significant memory deficits in the 2-day MWM protocol, whereas pretreatment with standardised APAE dose-dependently improved performance in the MWM test. APAE treatment also blocked the LPS-induced hippocampal increase in the concentration and expression of proinflammatory cytokines (TNF-α, IL-1β, and IL-6) and production of ROS and TBARS and enhanced the activities of AChE and BChE. Furthermore, APAE enhanced the decrease in the levels and expression of hippocampal antioxidant enzymes (SOD and CAT) following LPS-induced neuroinflammation and cognitive deficit. The findings from these studies suggested that standardised APAE improved memory and had potent neuroprotective effects against LPS-induced neurotoxicity.

Matched MeSH terms: Catalase
Hyptis verticillata attenuates dyslipidaemia, oxidative stress and hepato-renal damage in streptozotocin-induced diabetic rats

Ogar I, Egbung GE, Nna VU, Atangwho IJ, Itam EH

Life Sci, 2019 Feb 15;219:283-293.
PMID: 30668955 DOI: 10.1016/j.lfs.2019.01.027

AIMS: Chronic hyperglycaemia in diabetes mellitus (DM) increases the production of free radicals which results in oxidative stress and related disorders such as cardiovascular diseases, compromised hepatic and renal functions. Hyptis verticillata reportedly demonstrated glucose lowering activity in previous studies. The present study therefore evaluated the effect of H. verticillata on hyperglycaemia-induced dyslipidaemia, hepatorenal distortions, oxidative stress, as well as calculated indices of cardiovascular function.
METHODS: Wistar rats employed for this study consisted of normoglycaemic and diabetic rats in nine experimental groups. The normoglycaemic and diabetic rats were either treated with metformin (500 mg/kg b.w.), quercetin (10 mg/kg b.w.), or ethanol extract of H. verticillata leaf (250 mg/kg b.w. and 500 mg/kg b.w.) administered orally for 28 days.
KEY FINDINGS: Results revealed that H. verticillata significantly lowered blood glucose level, attenuated dyslipidaemia, decreased atherogenic coefficient, atherogenic and coronary risk indices, and increased cardioprotective index in diabetic rats. Also, H. verticillata significantly decreased serum urea, creatinine, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and unconjugated bilirubin levels, relative to untreated diabetic rats. Further, H. verticillata increased serum superoxide dismutase, catalase and glutathione peroxidase activities and glutathione level, and decreased malondialdehyde level in diabetic rats in a manner similar to metformin and quercetin. Histopathological investigation of the liver and kidney revealed restored hepatocytes and amelioration of congested interstitial blood vessel of the Bowman's space of the kidneys upon intervention with H. verticillata.
SIGNIFICANCE: H. verticillata in addition to its anti-hyperglycaemic activity ameliorates oxidative stress, dyslipidaemia, atherogenicity and hepatorenal lesions in DM.

Matched MeSH terms: Catalase
Fulltext Gastroprotective activity of a novel Schiff base derived dibromo substituted compound against ethanol-induced acute gastric lesions in rats

Saremi K, Rad SK, Tayeby F, Abdulla MA, Karimian H, Majid NA

BMC Pharmacol Toxicol, 2019 Feb 15;20(1):13.
PMID: 30770761 DOI: 10.1186/s40360-019-0292-z

BACKGROUND: Basic function of bromine in body is to activate pepsin production in gastritis with low acidity. The present study encompasses a broad in vivo study to evaluate gastroprotective activity of a novel dibromo substituted Schiff base complex against Sprague Dawley (SD) rats.
METHODS: 2, 2'-[1, 2-cyclohexanediylbis (nitriloethylidyne)]bis(4-bromophenol) (CNBP) is synthesized via a Schiff base reaction, using the related ketone and diamine as the starting materials. SD rats are divided as normal, ulcer control (5 ml/kg of 10% Tween 20), testing (10 and 20 mg/kg of CNBP) and reference groups (omeprazole 20 mg/kg). Except for the normal group, the rest of the groups are induced gastric ulcer by ethanol 1 h after the pre-treatment. Ulcer area, gastric wall mucus, and acidity of gastric content of the animal stomachs are measured after euthanization. Antioxidant activity of the compound is tested by Ferric reducing antioxidant power (FRAP) test and safety of the compound is identified through acute toxicity by [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Moreover, activities of superoxide dismutase (SOD), catalase (CAT), levels of prostaglandins E2 (PGE2) and also malondialdehyde (MDA) are determined.
RESULTS: Antioxidant activity of CNBP was approved via FRAP assay. Vast shallow hemorrhagic injury of gastric glandular mucosa was observed in the ulcer group compared to the CNBP-treated animals. Histological evaluations confirmed stomach epithelial defense effect of CNBP with drastic decrease of gastric ulceration, edema and leucocytes penetration of submucosal stratum. Immunostaining exhibited over-expression in HSP70 protein in CNBP-treated groups compared to that of the ulcer group. Also, gastric protein analysis showed low levels of MDA, PGE2 and high activity of SOD and CAT.
CONCLUSIONS: CNBP with noticeable antioxidant property showed gastroprotective activity in the testing rodents via alteration of HSP70 protein expression. Also, antioxidant enzyme activities which were changed after treatment with CNBP in the animals could be elucidated as its gastroprotective properties.

Matched MeSH terms: Catalase/metabolism
Fulltext Manilkara zapota (L.) P. Royen leaf water extract triggered apoptosis and activated caspase-dependent pathway in HT-29 human colorectal cancer cell line

Tan BL, Norhaizan ME

Biomed Pharmacother, 2019 Feb;110:748-757.
PMID: 30554113 DOI: 10.1016/j.biopha.2018.12.027

Manilkara zapota (L.) P. Royen (Family: Sapotaceae), commonly called as sapodilla, has been applied as traditional folk medicine for diarrhea and pulmonary infections. Conventional therapy in colorectal cancer is not likely effective due to undesirable outcomes. The anti-colon cancer properties of Manilkara zapota leaf water extract have yet to be investigated thus far. Therefore, our present study aimed to evaluate the ability to induce apoptosis and the underlying mechanisms of Manilkara zapota leaf water extract against human colorectal cancer (HT-29) cells. The cytotoxicity of Manilkara zapota leaf water extract was screened in different cancer cell lines using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) analyses. The morphological changes in HT-29 cell lines after exposure to Manilkara zapota leaf water extract were viewed under fluorescence and inverted light microscope. The apoptotic cell was measured by Annexin V-propidium iodide staining. The caspase-3 and -8 activities were assessed by colorimetric assay. Overall analyses revealed that treatment with Manilkara zapota leaf water extract for 72 h can inhibit the viability of HT-29 cells. Incubation with Manilkara zapota leaf water extract for 24, 48, and 72 h significantly increased (p < 0.05) the total apoptotic cells compared to the control. Treatment with 21, 42, and 84 μg/mL of Manilkara zapota leaf water extract for 72 h triggered both caspase-3 and -8 activities in a concentration-dependent pattern. We also found that the catalase level in the two treatment groups (21 and 42 μg/mL) was significantly elevated after 24 h incubation. Incubation with Manilkara zapota leaf water extract for 72 h triggered the transcriptional elevation of the adenomatous polyposis coli (APC), glycogen synthase kinase 3β (GSK3β), AXIN1, and casein kinase 1 (CK1). The β-catenin mRNA levels were reduced accordingly when the concentration of the Manilkara zapota leaf water extract was increased. Our results suggested that Manilkara zapota leaf water extract offer great potential against colorectal cancer through modulation of Wnt/β-catenin signaling pathway, caspase-dependent pathway, and antioxidant enzyme.

Matched MeSH terms: Catalase
Effects of Tualang honey in modulating nociceptive responses at the spinal cord in offspring of prenatally stressed rats

Abd Aziz CB, Ahmad Suhaimi SQ, Hasim H, Ahmad AH, Long I, Zakaria R

J Integr Med, 2019 Jan;17(1):66-70.
PMID: 30591413 DOI: 10.1016/j.joim.2018.12.002

OBJECTIVE: This study was done to determine whether Tualang honey could prevent the altered nociceptive behaviour, with its associated changes of oxidative stress markers and morphology of the spinal cord, among the offspring of prenatally stressed rats.
METHODS: Pregnant rats were divided into three groups: control, stress, and stress treated with Tualang honey. The stress and stress treated with Tualang honey groups were subjected to restraint stress from day 11 of pregnancy until delivery. Ten week old male offspring (n = 9 from each group) were given formalin injection and their nociceptive behaviours were recorded. After 2 h, the rats were sacrificed, and their spinal cords were removed to assess oxidative stress activity and morphology. Nociceptive behaviour was analysed using repeated measures analysis of variance (ANOVA), while the levels of oxidative stress parameters and number of Nissl-stained neurons were analysed using a one-way ANOVA.
RESULTS: This study demonstrated that prenatal stress was associated with increased nociceptive behaviour, changes in the oxidative stress parameters and morphology of the spinal cord of offspring exposed to prenatal stress; administration of Tualang honey reduced the alteration of these parameters.
CONCLUSION: This study provides a preliminary understanding of the beneficial effects of Tualang honey against the changes in oxidative stress and neuronal damage in the spinal cord of the offspring of prenatally stressed rats.

Matched MeSH terms: Catalase/metabolism
Fulltext Neuroprotective effects of 1`δ-1`-acetoxyeugenol acetate on Aβ(25-35) induced cognitive dysfunction in mice

Jayasingh Chellammal HS, Veerachamy A, Ramachandran D, Gummadi SB, Manan MM, Yellu NR

Biomed Pharmacother, 2019 Jan;109:1454-1461.
PMID: 30551397 DOI: 10.1016/j.biopha.2018.10.189

The progressive accumulation of amyloid beta (Aβ) peptide is neurotoxic and leads to Alzheimer's type dementia. Accumulation of Aβ has been associated with dysfunction of hypothalamic-pituitary-adrenal (HPA) axis and elevated pro-inflammatory cytokines. In this study, we investigated the effect of 1`δ-1`-acetoxyeugenol acetate (DAEA), isolated from Alpinia galanga (L.), on Aβ(25-35) induced neurodegeneration in mice. Mice were treated with three different doses of DAEA (12.5 mg/kg, 25 mg/kg and 50 mg/kg) for 28 days. Aβ(25-35) was injected by intracerebroventricular (i.c.v.) injection on the 15th day of 28 days. Open field, water maze and step-down inhibitory tests were performed on the 27th day to determine the habituation memory, spatial learning, and short- and long-term memory, respectively. Acetylcholinesterase (AChE), Corticosterone, biogenic amines (serotonin and dopamine), tumour necrosis factor-α (TNF-α), and antioxidant parameters such as superoxide dismutase, catalase, glutathione peroxidase and vitamin C were evaluated in brain homogenates after behavioural tests to ascertain the cognitive improvement through neuro-immune-endocrine modulation. The DAEA treatment with 25 mg/kg and 50 mg/kg resulted in significant (p < 0.001) improvement of habituation memory and step-down inhibitory avoidance task. In spatial learning, the cognitive improvement was significantly improved (p < 0.001) by reduction in escape latency. In the biochemical study, the significant (p < 0.001) reduction of AChE indicates the preeminent neuroprotection. Corticosterone and TNF-α were significantly (p < 0.01) reduced and biogenic amines were increased with antioxidant markers, which signify the potential influence of DAEA on neuroprotection. Our investigation revealed that the drug DAEA attenuates stress mediated through the HPA axis and regulates the neuroendocrine and neuroimmune function to improve the cognition. DAEA could be a potential lead candidate for the treatment of neurodegeneration.

Matched MeSH terms: Catalase/metabolism
Oxidative stress and sperm function: A systematic review on evaluation and management

Dutta S, Majzoub A, Agarwal A

Arab J Urol, 2019;17(2):87-97.
PMID: 31285919 DOI: 10.1080/2090598X.2019.1599624

Objective: To review and present the most distinct concepts on the association of reactive oxygen species (ROS) with male reproduction. Methods: The Preferred Reporting Items for Systematic Reviews and Meta Analyses (PRISMA) guidelines were used to search PubMed, Medline, EMBASE, and the Cochrane electronic databases for studies investigating the role of oxidative stress (OS) on sperm function. Results: The literature search yielded 1857 studies, of which 1791 articles were excluded because of irrelevance of data, non-English language, non-human nature or because they were case reports or commentaries. All included studies were reviews (46), meta-analyses (one), original research studies (18) and guideline articles (one). The studies were published between 1984 and 2018. Under normal physiological conditions, ROS are vital for sperm maturation, hyperactivation, capacitation, acrosome reaction, as well as fertilisation. However, a number of endogenous and exogenous causes may induce supra-physiological levels of ROS resulting in lipid peroxidation, sperm DNA fragmentation and apoptosis, and consequently infertility. Several laboratory testing methods can be used in infertile men to diagnose OS. Treatment usually involves antioxidant supplementation and, when possible, elimination of the causative factor. Conclusion: OS is an important cause of male factor infertility. Its assessment provides essential information that can guide treatment strategies aimed at improving the male's reproductive potential. Abbreviations: bp: base-pair; CAT: catalase; LPO: lipid peroxidation; MDA: malondialdehyde; MiOXSYS: Male Infertility Oxidative System; mtDNA: mitochondrial DNA; NAD(PH): nicotinamide adenine dinucleotide (phosphate); NO: nitric oxide; 8-OHdG: 8-hydroxy-2'-deoxyguanosine; ORP: oxidation-reduction potential; OS: oxidative stress; PKA: protein kinase A; PLA2: phospholipase A2; PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses; PUFA: poly-unsaturated fatty acid; ROS: reactive oxygen species; SOD: superoxide dismutase; TAC: total antioxidant capacity; TBA: thiobarbituric acid.

Matched MeSH terms: Catalase
Fulltext Implisit judul berita pilihan raya umum ke-14

Faris Fakhira Tauran, Zaitul Azma Zainon Hamzah

Malaysian Journal of Social Sciences and Humanities, 2019;4(6):32-44.
MyJurnal

Kemenangan parti pembangkang dalam pilihan raya umum (PRU) kali ke-14 telah memecahkan tampuk pimpinan kerajaan lama yang telah memerintah selama 60 tahun. Pelbagai isu mengenai pilihan raya umum disiarkan menerusi media massa terutamanya media cetak. Media cetak seperti surat khabar juga tidak terlepas daripada menyiarkan pelbagai judul berita yang menarik. Walau bagaimanapun, terdapat beberapa judul berita yang ditulis menggunakan perkataan yang mempunyai makna implisit. Penggunaan perkataan yang mempunyai makna implisit ini akan menyukarkan pembaca untuk memahami judul yang dipaparkan. Kajian ini bertujuan untuk mengenal pasti dan membincangkan perkataan implisit yang terdapat dalam judul berita PRU ke-14. Kaedah yang dipilih bagi melaksanakan kajian ini ialah kaedah kualitatif. Selain itu, bahan kajian yang digunakan ialah surat khabar Berita Harian keluaran bulan April dan Mei bagi tahun 2018. Namun, berita yang dipilih hanya berfokus kepada berita PRU ke-14 yang mempunyai perkataan implisit sahaja. Setiap data yang dikumpul akan dikateorikan mengikut bentuk kata iaitu kata tunggal, kata terbitan dan kata majmuk. Data yang telah dikategorikan akan dianalisis dengan menggunakan teori semiotik. Hasil dapatan menunjukkan bahawa terdapat 28 judul berita PRU ke-14 yang menggunakan perkataan implisit. Kebanyakan perkataan implisit ini terdiri daripada kata majmuk iaitu sebanyak 18 judul, diikuti kata tunggal sebanyak 8 judul dan kata terbitan sebanyak 2 judul. Penggunaan perkataan implisit ini adalah bertujuan untuk menarik perhatian pembaca supaya membaca berita yang disiarkan. Justeru, kajian ini secara tidak langsung dapat menunjukkan bahawa berita bergenre politik juga turut menggunakan perkataan implisit dalam penulisan judul berita.

Matched MeSH terms: Catalase
Fulltext LACTIC ACID BACTERIA ISOLATED FROM LOCALLY PRODUCED VINEGARS AND THEIR ANTIBACTERIAL ACTIVITY AGAINST FOODBORNE BACTERIA

AGNES LEE CHIU NEE, MOHD NIZAM LANI, ROZILA ALIAS, ZAITON HASSAN

UMT Journal of Undergraduate Research, 2019;1(2):1-7.
MyJurnal

Vinegars are most widely used as preservatives in food industry. Vinegars are known for their health benefits; however, the roles of vinegar-associated microflora in locally produced vinegars are not well established. The objectives of this study are to isolate and identify the lactic acid bacteria (LAB) from black rice vinegar and coconut vinegar, measure their pH and titratable acidity, and determine their antibacterial activity. LAB was isolated using cultural method. Phenotypic characterization of LAB was carried out using Gram-staining, oxidase test, catalase test and API 50 CHL Kit. Results from API 50 CHL Kit confirmed that BRV03M strain from black rice vinegar and CV03M strain from coconut vinegar were Lactobacillus paracaseissp. paracasei. The identified bacteria in both samples were consistent as L. paracaseiusing 16S rDNAgene sequences with 93% and 99% similarity, respectively. The pH and titratable acidity percentage of both vinegars were also determined. The stability of Cell Free Supernatant-Lactic Acid Bacteria (CFS-LAB) strains within 14 days on their inhibition against selected pathogenic bacteria was determined using agar well diffusion method. The CFS-LAB strain isolated from black rice vinegar (BRV03M) was more stable within 14 days than coconut vinegar in inhibiting tested bacteria, suggesting this strain has great potential as natural antibacterial agents.

Matched MeSH terms: Catalase
Fulltext Effect of protocatechuic acid-layered double hydroxide nanoparticles on diethylnitrosamine/phenobarbital-induced hepatocellular carcinoma in mice

Gani SA, Muhammad SA, Kura AU, Barahuie F, Hussein MZ, Fakurazi S

PLoS One, 2019;14(5):e0217009.
PMID: 31141523 DOI: 10.1371/journal.pone.0217009

Researchers investigating cancer chemotherapy and management continue to search for agents that selectively kill malignant cells and leave healthy neighboring cells intact. Natural products provide relevant resources for anti-cancer drug discovery. However, the physicochemical properties of these compounds limit their efficient uptake and bioavailability. We introduced a nanocarrier system, namely, zinc-aluminum-layered double hydroxide (ZnAl-LDH) intercalated with protocatechuic acid. In this study, the efficacy and toxicity of protocatechuic acid intercalated in zinc aluminum-layered double hydroxide nanoparticles (PCA-ZnAl) against diethylnitrosamine/phenobarbital (DEN/PB)-induced hepatocellular carcinoma (HCC) in BALB/c mice was evaluated. HCC in male mice was induced by a single-dose intraperitoneal administration of DEN and was promoted by the introduction of PB via drinking water for 12 weeks. HCC induction was confirmed after the DEN/PB introduction period by measurement of the elevated level of serum α-feto protein (AFP). The results showed that the level of α-fetoprotein was significantly reduced in PCA-ZnAl (350±43.90 ng/mL), doxorubicin (DOX) (290±20.52 ng/mL) and ZnAl-LDH (390±19.65 ng/mL) treated animals compared to HCC mice treated with normal saline (580.4± 52.04 ng/mL). Superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) levels were significantly increased, whereas the level of lipid peroxidation was significantly decreased in HCC mice treated with DOX, PCA-ZnAl and ZnAl-LDH compared with those in HCC mice treated with saline. Restoration of hepatocyte morphology was observed following treatment that was comparable to that in the normal control group. Deterioration of hepatic cells and a significant increase of aspartate transaminase (AST), alanine transaminase (ALT), and alkaline phosphatase (ALP) were observed in the cancer-induced untreated group compared with that in the groups treated with nanoparticles. The histopathological features of the liver obtained from PCA-ZnAl-treated mice showed a uniform size with a similar distribution of the nuclear-cytoplasmic ratio and nucleus centrally located in the cytoplasm, similar to the normal liver cells. The results underscored the potential of PCA-ZnAl for the treatment of hepatocellular carcinoma.

Matched MeSH terms: Catalase
Fulltext Imbalanced oxidative stress and pro-inflammatory markers differentiate the development of diabetic neuropathy variants in streptozotocin-induced diabetic rats

Ismail CAN, Aziz CBA, Suppian R, Long I

J Diabetes Metab Disord, 2018 Dec;17(2):129-136.
PMID: 30918846 DOI: 10.1007/s40200-018-0350-x

Purpose: Diabetic neuropathy is a prolonged symptom of diabetes mellitus that affect a number of diabetes mellitus patients. So far, the variants of diabetic neuropathy, either painful (PDN) or non-painful (or painless, non-PDN) response have distinctive clinical entities. This study aims to determine the effects of oxidative stress parameters and pro-inflammatory factors at spinal cord level of streptozotocin-induced diabetic neuropathy rat model.
Methods: Thirty Sprague-Dawley rats were randomly assigned to control (non-diabetic), PDN and non-PDN groups (n = 10). The rats were induced with diabetes by streptozotocin injection (60 mg/kg). Tactile allodynia and thermal hyperalgesia were assessed on day 0, 14 (week 2) and 21 (week 3) in the rats. The rats were sacrificed and the spinal cord tissue was collected for the measurement of oxidative stress (malondialdehyde (MDA), superoxide dismutase (SOD) and catalase) and pro-inflammatory markers (interleukin-1β (IL-1β) and tumour necrosis factor-α (TNF-α)).
Results: PDN rats demonstrated a marked tactile allodynia with no thermal hyperalgesia whilst non-PDN rats exhibited a prominent hypo-responsiveness towards non-noxious stimuli and hypoalgesia towards thermal input. The MDA level and pro-inflammatory TNF-α was significantly increased in PDN rats whilst catalase was reduced in these rats. Meanwhile, non-PDN rats demonstrated reduced SOD enzyme activity and TNF-α level and increased MDA and catalase activity.
Conclusion: The changes in oxidative stress parameters and pro-inflammatory factors may contribute to the changes in behavioural responses in both PDN and non-PDN rats.

Matched MeSH terms: Catalase
Fulltext Taurine protects against retinal and optic nerve damage induced by endothelin-1 in rats via antioxidant effects

Nor Arfuzir NN, Agarwal R, Iezhitsa I, Agarwal P, Sidek S, Ismail NM

Neural Regen Res, 2018 Nov;13(11):2014-2021.
PMID: 30233077 DOI: 10.4103/1673-5374.239450

Endothelin-1 (ET-1), a potent vasoconstrictor, is involved in retinal vascular dysregulation and oxidative stress in glaucomatous eyes. Taurine (TAU), a naturally occurring free amino acid, is known for its neuroprotective and antioxidant properties. Hence, we evaluated its neuroprotective properties against ET-1 induced retinal and optic nerve damage. ET-1 was administered intravitreally to Sprague-Dawley rats and TAU was injected as pre-, co- or post-treatment. Animals were euthanized seven days post TAU injection. Retinae and optic nerve were examined for morphology, and were also processed for caspase-3 immunostaining. Retinal redox status was estimated by measuring retinal superoxide dismutase, catalase, glutathione, and malondialdehyde levels using enzyme-linked immuosorbent assay. Histopathological examination showed significantly improved retinal and optic nerve morphology in TAU-treated groups. Morphometric examination showed that TAU pre-treatment provided marked protection against ET-1 induced damage to retina and optic nerve. In accordance with the morphological observations, immunostaining for caspase showed a significantly lesser number of apoptotic retinal cells in the TAU pre-treatment group. The retinal oxidative stress was reduced in all TAU-treated groups, and particularly in the pre-treatment group. The findings suggest that treatment with TAU, particularly pre-treatment, prevents apoptosis of retinal cells induced by ET-1 and hence prevents the changes in the morphology of retina and optic nerve. The protective effect of TAU against ET-1 induced retinal and optic nerve damage is associated with reduced retinal oxidative stress.

Matched MeSH terms: Catalase
Fulltext Effects of Quercetin on Tubular Cell Apoptosis and Kidney Damage in Rats Induced by Titanium Dioxide Nanoparticles

Alidadi H, Khorsandi L, Shirani M

Malays J Med Sci, 2018 Mar;25(2):72-81.
PMID: 30918457 DOI: 10.21315/mjms2018.25.2.8

Background: Recent studies have demonstrated that many nanoparticles have an adverse or toxic effect on the kidney.
Objective: To investigate the nephroprotective effect of quercetin (QT) against renal injury induced by titanium dioxide nanoparticles (NTiO2) in rats.
Methods: NTiO2-intoxicated rats received 50 mg/kg of NTiO2 for seven days. The QT + NTiO2 group was pretreated with QT for seven days before being administered NTiO2. Uric acid, creatinine, and blood urea nitrogen were considered to be biomarkers of nephrotoxicity. Catalase (CAT) and superoxide dismutase (SOD) activities and renal levels of malondialdehyde (MDA) were measured to assess the oxidative stress caused by NTiO2.
Results: NTiO2 significantly increased the plasma level of the biomarkers. It also significantly decreased the activities of CAT (P = 0.008) and SOD (P = 0.004), and significantly increased the MDA levels (P = 0.007). NTiO2 caused proximal tubule damage, the accumulation of red blood cells, the infiltration of inflammatory cells, and reduced the glomerular diameters, as well as induced apoptosis in the proximal tubules. Pre-treatment with QT attenuated the histological changes, normalised the plasma biomarkers, suppressed oxidative stress, ameliorated the activities of CAT (P = 0.007) and SOD (P = 0.006), and reduced apoptosis (P < 0.001).
Conclusion: QT was found to have a potent protective effect against nephrotoxicity induced by NTiO2 in rats. It also reduced apoptosis caused by NTiO2.

Matched MeSH terms: Catalase
Investigation on Secondary Structure Perturbations of Proteins Embedded in Solid Lipid Matrices as a Novel Indicator of their Biological Activity upon In Vitro Release

Zeeshan F, Tabbassum M, Jorgensen L, Medlicott NJ

AAPS PharmSciTech, 2018 Feb;19(2):769-782.
PMID: 29134579 DOI: 10.1208/s12249-017-0883-1

Protein biologics are prone to conformational changes during formulation development. Limited methods are available for conformational analysis of proteins in solid state and in the presences of formulation excipients. The aim of this study was to investigate the secondary structures of proteins encased in solid lipid matrices as a novel indicator of their stability upon in vitro release. Model proteins namely catalase and lysozyme were incorporated into lipid namely Precirol® AT05 (glycerol palmitostearate, melting point 58°C) at 30% w/w loading using melting and mixing and wet granulation methods. Attenuated total reflectance (ATR-FTIR) spectroscopy, size-exclusion chromatography (SEC) and biological activity analyses were performed. The information about secondary structure was acquired using second derivative analysis of amide-I band (1600-1700 cm-1). ATR analysis demonstrated interference of lipid spectrum with protein amide-I band which was subsequently subtracted to allow the analysis of the secondary structure. ATR spectra amide-I bands showed shifts peak band positions compared to native protein for matrices prepared using wet granulation. SEC analysis gave evidence of protein aggregation for catalase which was increased using wet granulation. The biological activity of catalase was statistically different from that of control and was affected by the incorporation method and was found to be in alignment with ATR spectral changes and extent of aggregation. In conclusion, ATR spectroscopy could analyze protein secondary structure in lipid matrices provided lipid interference was minimized. The ATR spectral changes and formation of aggregates can indicate the loss in biological activity of protein released from solid lipid matrices.

Matched MeSH terms: Catalase/chemistry
Evaluation of the Antioxidative and Hypo-cholesterolemic Effects of Lingzhi or Reishi Medicinal Mushroom, Ganoderma lucidum (Agaricomycetes), in Ameliorating Cardiovascular Disease

Rahman MA, Abdullah N, Aminudin N

Int J Med Mushrooms, 2018;20(10):961-969.
PMID: 30806268 DOI: 10.1615/IntJMedMushrooms.2018028370

Oxidative stress (OS) and hypercholesterolemia have been linked with a heightened risk of cardiovascular disease (CVD). Because of the numerous drawbacks of synthetic antioxidants and cholesterol-lowering drugs, natural antioxidative and hypocholesterolemic agents are of immense importance. This study was designed to determine both the OS-attenuating and cholesterol-lowering capacities of the hot water extract (HWE) and of five solvent-solvent-partitioned fractions of Ganoderma lucidum. In vitro antioxidative performance of G. lucidum HWE and fractions was measured through DPPH free radical scavenging, Folin-Ciocalteu assay, lipid peroxidation inhibition, and human low-density lipoprotein (LDL) oxidation inhibition. In vivo antioxidative performance of G. lucidum was assessed by measuring the plasma and liver antioxidative enzymatic activities (catalase, glutathione peroxidase, and superoxide dismutase) in G. lucidum HWE-fed rats. In the CVD tests, the HWE at 200 mg/kg b.w. lowered plasma levels of total cholesterol, triacylglycerol, and LDL cholesterol and increased high-density lipoprotein cholesterol. The current findings indicate the therapeutic potentiality of G. lucidum as an OS-attenuating and hypocholesterolemic agent en route to withstanding CVD complications.

Matched MeSH terms: Catalase

Filters

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links