scholarly journals Promethazine inhibits the formation of aldehydic products of lipid peroxidation but not covalent binding resulting from the exposure of rat liver fractions to CCl4

1989 ◽  
Vol 264 (2) ◽  
pp. 527-532 ◽  
Author(s):  
G Poli ◽  
K H Cheeseman ◽  
F Biasi ◽  
E Chiarpotto ◽  
M U Dianzani ◽  
...  
Keyword(s):  
Lipid Peroxidation ◽  
Free Radical ◽  
Covalent Binding ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Isolated Hepatocytes ◽  
Peroxyl Radicals ◽  
Liver Necrosis ◽  
Lipid Peroxyl Radicals ◽  
Carbonyl Products

Promethazine is known to have protective activity in relation to CCl4-induced liver necrosis. This hepatoprotective property has been investigated with regard to the free radical scavenging and antioxidant properties of promethazine using isolated hepatocytes and microsomal suspensions. CCl4 is activated in both systems to free radical metabolites that bind covalently to lipid and protein, and initiate lipid peroxidation. A large number of carbonyl products is produced during CCl4-induced lipid peroxidation; promethazine strongly inhibits the production of all classes of carbonyl compounds in both microsomal suspensions and isolated hepatocytes. In contrast, promethazine is a very weak inhibitor of the covalent binding of metabolites of CCl4. We conclude that promethazine acts by scavenging the trichloromethylperoxyl radical and lipid peroxyl radicals, and is a weak scavenger of the trichloromethyl radical. These data, when considered together with the hepatoprotective effects of promethazine, suggest that lipid peroxidation is of relatively more importance than covalent binding in the pathogenesis of CCl4-induced liver necrosis.

scholarly journals Modulation of Ionizing Radiation Induced Oxidative Imbalance by Semi-Fractionated Extract ofPiper betle: An In Vitro and In Vivo Assessment

2010 ◽  
Vol 3 (1) ◽  
pp. 44-52 ◽  
Author(s):  
Savita Verma ◽  
Manju Lata Gupta ◽  
Ajaswrata Dutta ◽  
Sanghmitra Sankhwar ◽  
Sandeep Kumar Shukla ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Lipid Peroxidation ◽  
Free Radical ◽  
Ionizing Radiation ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Antioxidant Potential ◽  
Normal Tissues ◽  
Radiation Induced

The study was planned to evaluate modulatory effect of aqueous extract ofPiper betleleaf (PBL) on ionizing radiation mediated oxidative stress leading to normal tissues damage during radiotherapy and other radiation exposures. The total polyphenols and flavonoids known as free radical scavenger (chelators) were measured in the extract. To ascertain antioxidant potential of PBL extract, we studied free radical scavenging, metal chelation, reducing power, lipid peroxidation inhibition and ferric reducing antioxidant properties (FRAP ) using in vitro assays. Mice were exposed to varied radiation doses administered with the same extract prior to irradiation to confirm its oxidative stress minimizing efficacy by evaluating ferric reducing ability of plasma, reduced glutathione, lipid peroxidation and micro-nuclei frequency. PBL extract was effective in scavenging DPPH (up to 92% at 100 µg/ml) and superoxide radicals (up to 95% at 80 µg/ml), chelated metal ions (up to 83% at 50 µg/ml) and inhibited lipid peroxidation (up to 45.65% at 500 µg/ml) in a dose dependant manner using in vitro model. Oral administration of PBL extract (225 mg/kg body weight) 1 hr before irradiation in mice significantly enhanced (p < 0.01) radiation abated antioxidant potential of plasma and GSH level in all the observed organs. The treatment with extract effectively lowered the radiation induced lipid peroxidation at 24 hrs in all the selected organs with maximum inhibition in thymus (p < 0.01). After 48 hrs, lipid peroxidation was maximally inhibited in the group treated with the extract. Frequency of radiation induced micronucleated cells declined significantly (34.78%, p < 0.01) at 24 hrs post-irradiation interval by PBL extract administration. The results suggest that PBL extract has high antioxidant potential and relatively non-toxic and thus could be assertively used to mitigate radiotherapy inflicted normal tissues damage and also injuries caused by moderate doses of radiation during unplanned exposures.

Flavones and Their Analogues as Bioactive Compounds – An Overview

2019 ◽  
Vol 16 (4) ◽  
pp. 377-391 ◽  
Author(s):  
B.S. Jayashree ◽  
H. Venkatachalam ◽  
Sanchari Basu Mallik
Keyword(s):  
Biological Activity ◽  
Free Radical ◽  
Bioactive Compounds ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Cost Effective ◽  
Free Radical Scavenging ◽  
Polyphenolic Compounds ◽  
Pharmacological Activities ◽  
Poor Solubility

Flavonoids constitute a large group of polyphenolic compounds that are known to have antioxidant properties, through their free radical scavenging abilities. They possess a chromone (γ- benzopyrone) moiety, responsible for eliciting many pharmacological activities. Even though, natural flavonoids are highly potent, owing to their poor solubility, they are less used. Therefore, attempts have been made to improve their stability, solubility, efficacy and kinetics by introducing various substituents on the flavone ring. For nearly the last two decades, flavones were synthesized in our laboratory by simple, convenient and cost-effective methods, with the knowledge of both synthetic and semi-synthetic chemistry. In this direction, it was considered worthwhile to present an overview on the synthesized flavonoids. This review creates a platform for highlighting various modifications done on the flavone system along with their biological activity.

scholarly journals The mechanism of Fe2+-initiated lipid peroxidation in liposomes: the dual function of ferrous ions, the roles of the pre-existing lipid peroxides and the lipid peroxyl radical

2000 ◽  
Vol 352 (1) ◽  
pp. 27-36 ◽  
Author(s):  
Lixia TANG ◽  
Yong ZHANG ◽  
Zhongming QIAN ◽  
Xun SHEN
Keyword(s):  
Lipid Peroxidation ◽  
Latent Period ◽  
Time Lag ◽  
Lipid Peroxides ◽  
Peroxyl Radicals ◽  
Dual Function ◽  
Critical Ratio ◽  
Ferrous Ions ◽  
Liposomal System ◽  
Lipid Peroxyl Radicals

The mechanism of Fe2+-initiated lipid peroxidation in a liposomal system was studied. It was found that a second addition of ferrous ions within the latent period lengthened the time lag before lipid peroxidation started. The apparent time lag depended on the total dose of Fe2+ whenever the second dose of Fe2+ was added, which indicates that Fe2+ has a dual function: to initiate lipid peroxidation on one hand and suppress the species responsible for the initiation of the peroxidation on the other. When the pre-existing lipid peroxides (LOOH) were removed by incorporating triphenylphosphine into liposomes, Fe2+ could no longer initiate lipid peroxidation and the acceleration of Fe2+ oxidation by the liposomes disappeared. However, when extra LOOH were introduced into liposomes, both enhancement of the lipid peroxidation and shortening of the latent period were observed. When the scavenger of lipid peroxyl radicals (LOOP), N,N´-diphenyl-p-phenylene-diamine, was incorporated into liposomes, neither initiation of the lipid peroxidation nor acceleration of the Fe2+ oxidation could be detected. The results may suggest that both the pre-existing LOOH and LOOP are necessary for the initiation of lipid peroxidation. The latter comes initially from the decomposition of the pre-existing LOOH by Fe2+ and can be scavenged by its reaction with Fe2+. Only when Fe2+ is oxidized to such a degree that LOOP is no longer effectively suppressed does lipid peroxidation start. It seems that by taking the reactions of Fe2+ with LOOH and LOOP into account, the basic chemistry in lipid peroxidation can explain fairly well the controversial phenomena observed in Fe2+-initiated lipid peroxidation, such as the existence of a latent period, the critical ratio of Fe2+ to lipid and the required oxidation of Fe2+.

scholarly journals Ethanol Extract of Maclura tricuspidata Fruit Protects SH-SY5Y Neuroblastoma Cells against H2O2-Induced Oxidative Damage via Inhibiting MAPK and NF-κB Signaling

2021 ◽  
Vol 22 (13) ◽  
pp. 6946
Author(s):  
Weishun Tian ◽  
Suyoung Heo ◽  
Dae-Woon Kim ◽  
In-Shik Kim ◽  
Dongchoon Ahn ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Free Radical ◽  
Oxidative Damage ◽  
Cell Damage ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Biologically Active ◽  
Mitogen Activated Protein Kinase ◽  
Protective Effects ◽  
Neuroprotective Effects

Free radical generation and oxidative stress push forward an immense influence on the pathogenesis of neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease. Maclura tricuspidata fruit (MT) contains many biologically active substances, including compounds with antioxidant properties. The current study aimed to investigate the neuroprotective effects of MT fruit on hydrogen peroxide (H2O2)-induced neurotoxicity in SH-SY5Y cells. SH-SY5Y cells were pretreated with MT, and cell damage was induced by H2O2. First, the chemical composition and free radical scavenging properties of MT were analyzed. MT attenuated oxidative stress-induced damage in cells based on the assessment of cell viability. The H2O2-induced toxicity caused by ROS production and lactate dehydrogenase (LDH) release was ameliorated by MT pretreatment. MT also promoted an increase in the expression of genes encoding the antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT). MT pretreatment was associated with an increase in the expression of neuronal genes downregulated by H2O2. Mechanistically, MT dramatically suppressed H2O2-induced Bcl-2 downregulation, Bax upregulation, apoptotic factor caspase-3 activation, Mitogen-activated protein kinase (MAPK) (JNK, ERK, and p38), and Nuclear factor-κB (NF-κB) activation, thereby preventing H2O2-induced neurotoxicity. These results indicate that MT has protective effects against H2O2-induced oxidative damage in SH-SY5Y cells and can be used to prevent and protect against neurodegeneration.

Investigation of Free Radical Scavenging Enzyme Activities and Lipid Peroxidation in Human Placental Tissues With Miscarriage

2006 ◽  
Vol 13 (5) ◽  
pp. 384-388 ◽  
Author(s):  
Aydan Biri ◽  
Mustafa Kavutcu ◽  
Nuray Bozkurt ◽  
Erdinç Devrim ◽  
Nilhan Nurlu ◽  
...  
Keyword(s):  
Lipid Peroxidation ◽  
Free Radical ◽  
Enzyme Activities ◽  
Radical Scavenging ◽  
Free Radical Scavenging

Strong antihemolytic and antioxidant properties of aqueous extract from Algerian Hammada elegans (Bge.) Botsch (Chenopodiaceae)

2021 ◽  
Vol 17 ◽  
Author(s):  
Brahim Asseli ◽  
Reguia Mahfoudi ◽  
Amar Djeridane ◽  
Mohamed Yousfi
Keyword(s):  
Free Radical ◽  
Aqueous Extract ◽  
Radical Scavenging Activity ◽  
Condensed Tannin ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Total Phenolic ◽  
Dependent Manner ◽  
Vitro Assay

Background: Research on medicinal plant antioxidants has emerged as a potential therapeutic to prevent free radical generated damage in the human body. Hammada elegans Botsch (popularly known as “Ajram”) is a xerophytic plant widely found in Laghouat region, but there are only a few reports about the biological or chemical properties of these species. Hence, the aim of this study is to investigate the antioxidant and the antihemolytic activities of hexanic, acetonic, methanolic and aqueous extracts of aerial parts of Algerian Hammada elegans Botsch by employing different in vitro assay systems. Methods: The total phenolic content, the flavonoid content and the condensed tannin amount were analyzed using Folin-Ciocalteu, aluminum chloride and vanillin assays, respectively. The in vitro antioxidant capacity of extracts was assessed by CUPRAC, iron chelating, ABTS•+and antihemolytic assays, and was expressed as EC50 values. Results: Among the analyzed extracts, the aqueous extract had the highest phenolic, flavonoid and tannin contents. Also, this extract displayed the highest antioxidant capacities compared to the other extracts and standards. Its EC50 value for ABTS radical-scavenging activity was 0.265 ± 0.003 mg/L. Moreover, this extract showed high iron (II) chelating ability (EC50 = 0.958 ± 0.001 mg/L), and good antioxidant activity in the cupric ion reducing activity (CUPRAC) in a concentration dependent manner (EC50 were 0.709 ± 0.002 mg/L). Additionally, this extract had the best antihemolytic activity against AAPH-induced hemolysis (EC50=0.090 ± 0.004 mg/L). Conclusion: Our study revealed that the aqueous extract of Hammada elegans Botsch, is a potential source of antioxidants which possess a high protective effect of membrane against free radical.

Antioxidant and Antifungal Properties of Benzimidazole Derivatives

2010 ◽  
Vol 65 (9-10) ◽  
pp. 537-542 ◽  
Author(s):  
Canan Kuş ◽  
Fatma Sözüdönmez ◽  
Benay Can-Eke ◽  
Tülay Çoban
Keyword(s):  
Lipid Peroxidation ◽  
Free Radical ◽  
Radical Scavenging ◽  
Liver Microsomes ◽  
Thiobarbituric Acid ◽  
Benzimidazole Derivatives ◽  
Rat Liver Microsomes ◽  
Inhibitory Effects ◽  
Stable Free Radical ◽  
Radical Scavenging Properties

Antioxidant and radical scavenging properties of a series of 2-[4-(substituted piperazin-/ piperidin-1-ylcarbonyl)phenyl]-1H-benzimidazole derivatives were examined. Free radical scavenging properties of compounds 11-30 and 33 were evaluated for the stable free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide anion radical. In addition the inhibitory effects on the NADPH-dependent lipid peroxidation levels were determined by measuring the formation of 2-thiobarbituric acid reactive substances (TBARS) using rat liver microsomes. Compound 33 which has a p-fluorobenzyl substitutent at position 1 exhibited the strongest inhibition (83%) of lipid peroxidation at a concentration of 10-3 M, while the nonsubstituted analogue 13 caused 57% inhibition. This result is fairly consistent with the antimicrobial activity results against both Staphylococcus aureus and Candida albicans.

Plant polyphenols: free radical scavengers or chain-breaking antioxidants?

1995 ◽  
Vol 61 ◽  
pp. 103-116 ◽  
Author(s):  
Catherine Rice-Evans
Keyword(s):  
Biological Effects ◽  
Relative Effectiveness ◽  
Antioxidant Properties ◽  
Peroxyl Radicals ◽  
Free Radical Scavengers ◽  
Dietary Polyphenols ◽  
Chain Breaking ◽  
Lipid Peroxyl Radicals

There is increasing interest in the biological effects of tea- and wine-derived polyphenols and many studies in vitro and in vivo are demonstrating their antioxidant properties. Tea is a major source of dietary polyphenols and an even richer source of the flavanols, the catechins and catechin/gallate esters. Although there are limited studies on the bioavailability of the polyphenols, the absorption of flavanols in humans has been shown. The studies described in this chapter discuss the relative antioxidant potentials of the polyphenolic flavonoids in vitro against radicals generated in the aqueous phase in comparison with their relative effectiveness as antioxidants against propagating lipid peroxyl radicals, and how their activity influences that of α-tocopherol in low-density lipoproteins exposed to oxidative stress.

scholarly journals In vitro inhibitory potentials of ethanolic extract of Moringa oleifera flower against enzymes activities linked to diabetes

2021 ◽  
Vol 10 (4) ◽  
pp. 408-414
Author(s):  
Oluwaseun Ruth Olasehinde ◽  
Olakunle Bamikole Afolabi ◽  
Benjamin Olusola Omiyale ◽  
Oyindamola Adeniyi Olaoye
Keyword(s):  
Free Radical ◽  
Moringa Oleifera ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Ethanolic Extract ◽  
Antidiabetic Activity ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Antioxidant Power

Introduction: Diabetes mellitus (DM) has been recognized as the seventh leading cause of global mortality; however, researchers seek alternative means to manage the menace. The current study sought to investigate antioxidant potentials, α-amylase, and α-glucosidase inhibitory activities of ethanolic extract of Moringa oleifera flower in vitro. Methods: Antioxidant properties of the extract were appraised by assessing its inhibition against 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl (OH•), and hydrogen peroxide (H2O2) free radicals, as well as ferric reducing antioxidant power (FRAP), the antidiabetic activity was evaluated by α-amylase and α-glucosidase inhibition.Results: In this study, ethanolic extract of M. oleifera flower demonstrated a significant (P < 0.05) inhibition against DPPH free radical (43.57–83.56%) in a concentration-dependent manner, while FRAP (101.76 ± 1.63 mg/100 g), OH• scavenging ability (71.62 ± 0.95 mg/100 g), and H2O2 free radical scavenging capacity (15.33 ± 1.20 mg/100 g) were also observed. In the same manner, ethanolic extract of M. oleifera flower revealed a significant (P < 0.05) inhibition against α-amylase (IC50= 37.63 mg/mL) and α-glucosidase activities (IC50= 38.30 mg/mL) in the presence of their respective substrates in a concentration-dependent manner in comparison with acarbose. Conclusion: Ethanoic extract of M. oleifera flower could be useful as an alternative phytotherapy in the management of DM, having shown a strong antioxidative capacity and substantial inhibition against the activities of key enzymes involved in carbohydrate hydrolysis in vitro.

scholarly journals Antioxidant and antimicrobial activities against Enterobacter cloacae of extracts of Eclipta alba Hassk.

2016 ◽  
Vol 19 (4) ◽  
pp. 76-83
Author(s):  
Trang Thi Xuan Dai ◽  
Anh Thi Tu Vo
Keyword(s):  
Free Radical ◽  
Vitamin C ◽  
Ethyl Acetate ◽  
Ethyl Acetate Extract ◽  
Antioxidant Properties ◽  
Radical Scavenging ◽  
Enterobacter Cloacae ◽  
Free Radical Scavenging ◽  
Antioxidant Vitamin ◽  
Eclipta Alba

This study was subjected to investigate antimicrobial and antioxidant properties of Eclipta alba extracts (methanol, hexane, chloroform and ethyl acetate extracts). The antioxidant property of the extract was assessed by 2,2- diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging method. Kirby-Bauer method was used to determine the antibacterial activity against Enterobacter cloacae of the extracts. The extracts of Eclipta alba were tested against E. cloacae. The highest antibacterial potentiality was exhibited by the ethyl acetate extract of E. alba leaves, means of zones of bacterial growth inhibition are 26.3 mm at a concentration of 32 μg/mL. DPPH free radical scavenging effect of the extracts was compared with standard antioxidant vitamin C. The highest antioxidant activity was exhibited by the ethyl acetate extract of E. alba leaves. The result also showed that the DPPH scavenging activity of ethyl acetate extract from leaves of E. alba was high (EC50 = 419.38 μg/mL). However, this result was 18.99 times lower than that of vitamin C (EC50 = 22.08 μg/mL).

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