Pro-oxidant Induced Lipid Peroxidation Research Articles

Antioxidant activities of ethanolic extract of Annona muricata against different pro-oxidant induced lipid peroxidation in rat brain and liver

Antioxidant activities of ethanolic extract of Annona muricata against different pro-oxidant induced lipid peroxidation in rat brain and liver

Modulatory effect of some citrus (Citrus limon, Citrus reticulata, Citrus maxima) peels on monoamine oxidase, phosphodiesterase-5 and angiotensin-1 converting enzyme activities in rat heart homogenate.

Background Citrus peels have been reported useful in folk medicine for the management of cardiovascular diseases, but there is dearth of information on the possible mechanisms for their therapeutic action. The aim of this study was to investigate the effect of methanolic extracts from some citrus [lime (Citrus limon), tangerine (Citrus reticulata), shaddock (Citrus maxima)] peels on some enzymes relevant to the management of cardiovascular diseases [monoamine oxidase (MAO), phosphodiesterase-5 (PDE-5) and angiotensin-1-converting enzyme (ACE)]. Methods Effect of methanolic extracts of lime, tangerine and shaddock peels on MAO, PDE-5 and ACE were carried out using standard methods. In addition, the ability of the extracts to prevent oxidative damage in rat heart homogenates was also investigated. Finally, the total polyphenol content of extracts was determined. Results The results revealed that methanolic extracts of lime, tangerine and shaddock peels inhibited MAO, PDE-5, ACE and pro-oxidants induced lipid peroxidation in rat heart homogenate in a concentration-dependent manner. Conclusions Findings in this study revealed citrus peel methanolic extracts as natural inhibitor of enzymes (MAO, PDE-5 and ACE) implicated in cardiovascular diseases. Therefore, citrus peels could help in the management of cardiovascular diseases possibly through inhibition of these enzymes.

Antioxidant activities and inhibitory effect of Taraxacum officinale, Cichorium intybus and Lectuca sativa on prooxidant induced lipid peroxidation in mice liver

Antioxidant activities and inhibitory effect of Taraxacum officinale, Cichorium intybus and Lectuca sativa on prooxidant induced lipid peroxidation in mice liver

In vitro inhibition of phosphodiesterase-5 and arginase activities from rat penile tissue by two Nigerian herbs (Hunteria umbellata and Anogeissus leiocarpus).

Anogeissus leiocarpus and Hunteria umbellata have been reportedly used in traditional medicine for the management of erectile dysfunction (ED). However, the scientific basis for their use has not been well established. Therefore, this study was designed to investigate the inhibitory effects of water extractable phytochemicals of H. umbellata and A. leiocarpus on phosphodiesterase-5 (PDE-5) and arginase as well as pro-oxidants induced lipid peroxidation in rat penile tissue. The effects of the extracts on important enzymes (PDE-5 and arginase) linked with ED and pro-oxidants (Fe2+ and sodium nitroprusside) induced lipid peroxidation were investigated. Also, radicals scavenging and metal chelating abilities were determined. In addition, phenolic contents were determined and characterized using HPLC. The results showed that both extracts inhibited PDE-5 and arginase activities in a dose-dependent manner. Inhibitory property of A. leiocarpus (IC50 - 174.19 μg/mL) was significantly better (p<0.05) than that of H. umbellata (IC50 - 537.72 μg/mL) in PDE-5 assay. The extracts were potent inhibitors of arginase than PDE-5, and these extracts were equally potent in inhibiting arginase. Furthermore, Fe2+ and sodium nitroprusside caused a significant increase in malondialdehyde content; however, both extracts reduced malondialdehyde level in concentration-dependent manner. It is noteworthy that both extracts scavenged radicals (OH* and ABTS*) and chelated Fe2+. HPLC analysis revealed abundance of rutin, chlorogenic acid, gallic acid, caffeic acid, and quercetin, among others. The ability of the extracts to inhibit PDE-5, arginase and pro-oxidant induced lipid peroxidation, and chelate metal might suggest their folkloric use for the management of ED.

Essential Oil Composition, Antioxidant, Antidiabetic and Antihypertensive Properties of Two Afromomum Species.

This study was designed to assess the antioxidant, antidiabetic and antihypertensive effects of essential oils from A. melegueta and A. danielli seeds. The essential oils were extracted via hydrodistillation, dried with anhydrous Na2SO4 and characterized using gas chromatography-mass spectrometry (GC-MS). Antioxidant properties and inhibition of some pro-oxidant induced lipid peroxidation in rats' pancreas and heart homogenates were also determined. The results revealed that eugenol, eucalyptol, α-terpineol, α-caryophyllene and β-caryophyllene were the most abundant components in A. melegueta and A. danielli seeds. The essential oils inhibited α-amylase, α-glucosidase and angiotensin-I-converting enzyme in vitro. A.melegueta oil showed a higher α-amylase and α- glucosidase inhibitory activities with EC50 values of 139.00 µL/mL and 91.83 µL/mL respectively than A. danielli. However, A. danielli oil (EC50 = 48.73 µL/mL) showed the highest ACE inhibitory acivity. The highest NO radical scavenging ability was observed in A. melegueta oil while A. danielli had the highest OH radical scavenging and Fe2+- chelating ability. Furthermore, both essential oils inhibited SNP and Fe2+- induced lipid peroxidation in rats' pancreas and heart respectively in a dose dependent manner. This study reveals the biochemical principle by which essential oils from A. danielli and A.melegueta seed elicits their therapeutic effects on type-2 diabetes and hypertension.

Essential Oil from Clove Bud (Eugenia aromatica Kuntze) Inhibit Key Enzymes Relevant to the Management of Type-2 Diabetes and Some Pro-oxidant Induced Lipid Peroxidation in Rats Pancreas in vitro.

The inhibition of enzymes involved in the breakdown of carbohydrates is considered a therapeutic approach to the management of type-2 diabetes. This study sought to investigate the effects of essential oil from clove bud on α-amylase and α-glucosidase activities. Essential oil from clove bud was extracted by hydrodistillation, dried with anhydrous Na2SO4 and characterized using gas chromatography-mass spectrometry (GC-MS). The effects of the essential oil on α-amylase and α-glucosidase activities were investigated. The antioxidant properties of the oil and the inhibition of Fe(2+) and sodium nitroprusside-induced malondialdehyde (MDA) production in rats pancreas homogenate were also carried out. The essential oil inhibited α-amylase (EC50=88.9 μl/L) and α-glucosidase (EC50=71.94 μl/L) activities in a dose-dependent manner. Furthermore, the essential oil inhibited Fe(2+) and SNP-induced MDA production and exhibited antioxidant activities through their NO*, OH*, scavenging and Fe(2+)- chelating abilities. The total phenolic and flavonoid contents of the essential oil were 12.95 mg/g and 6.62 mg/g respectively. GC-MS analysis revealed the presence of α-pinene, β-pinene, neral, geranial, gamma terpinene, cis-ocimene, allo ocimene, 1,8-cineole, linalool, borneol, myrcene and pinene-2-ol in significant amounts. Furthermore, the essential oils exhibited antioxidant activities as typified by hydroxyl (OH) and nitric oxide (NO)] radicals scavenging and Fe(2+)-chelating abilities. The inhibition of α-amylase and α-glucosidase activities, inhibition of pro-oxidant induced lipid peroxidation in rat pancreas and antioxidant activities could be possible mechanisms for the use of the essential oil in the management and prevention of oxidative stress induced type-2 diabetes.

Water Extractable Phytochemicals from Peppers (Capsicum spp.) Inhibit Acetylcholinesterase and Butyrylcholinesterase Activities and Prooxidants Induced Lipid Peroxidation in Rat Brain In Vitro.

Background. This study sought to investigate antioxidant capacity of aqueous extracts of two pepper varieties (Capsicum annuum var. accuminatum (SM) and Capsicum chinense (RO)) and their inhibitory effect on acetylcholinesterase and butyrylcholinesterase activities. Methods. The antioxidant capacity of the peppers was evaluated by the 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging ability and ferric reducing antioxidant property. The inhibition of prooxidant induced lipid peroxidation and cholinesterase activities in rat brain homogenates was also evaluated. Results. There was no significant difference (P > 0.05) in the total phenol contents of the unripe and ripe Capsicum spp. extracts. Ripe and unripe SM samples had significantly higher (P < 0.05) ABTS* scavenging ability than RO samples, while the ripe fruits had significantly higher (P < 0.05) ferric reducing properties in the varieties. Furthermore, the extracts inhibited Fe2+ and quinolinic acid induced lipid peroxidation in rats brain homogenates in a dose-dependent manner. Ripe and unripe samples from SM had significantly higher AChE inhibitory abilities than RO samples, while there was no significant difference in the BuChE inhibitory abilities of the pepper samples. Conclusion. The antioxidant and anticholinesterase properties of Capsicum spp. may be a possible dietary means by which oxidative stress and symptomatic cognitive decline associated with neurodegenerative conditions could be alleviated.

Essential Oil from Lemon Peels Inhibit Key Enzymes Linked to Neurodegenerative Conditions and Pro-oxidant Induced Lipid Peroxidation

This study sought to investigate the effects of essential oil from lemon (Citrus limoni) peels on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities in vitro. The essential oil was extracted by hydrodistillation, dried with anhydrous Na2SO4 and characterized using gas chromatography. Antioxidant properties of the oil and inhibition of pro-oxidant-induced lipid peroxidation in rats brain homogenate were also assessed. The essential oil inhibited AChE and BChE activities in a concentration-dependent manner. GC analysis revealed the presence of sabinene, limonene, α-pinene, β-pinene, neral, geranial, 1,8-cineole, linalool, borneol, α-terpineol, terpinen-4-ol, linalyl acetate and β-caryophyllene. Furthermore, the essential oil exhibited antioxidant activities as typified by ferric reducing property, Fe(2+)-chelation and radicals [DPPH, ABTS, OH, NO] scavenging abilities. The inhibition of AChE and BChE activities, inhibition of pro-oxidant induced lipid peroxidation and antioxidant activities could be possible mechanisms for the use of the essential oil in the management and prevention of oxidative stress-induced neurodegeneration.

Inhibitory effect of some tropical green leafy vegetables on key enzymes linked to Alzheimer's disease and some pro-oxidant induced lipid peroxidation in rats' brain.

This study sought to investigate the inhibitory effect of some commonly consumed Nigerian green leafy vegetables (raw and blanched) on acetylcholinesterase and butyrylcholinesterase (key enzyme linked to Alzheimer's disease) activities and some pro-oxidants (FeSO4, Sodium nitroprusside and Quinolinic acid) induced lipid peroxidation in rat brain in vitro. Three commonly consumed green leafy vegetables in Nigeria [Amarantus cruentus (Arowojeja), Struchium sparganophora (Ewuro-odo) and Telfairia occidentalis (Ugwu] were blanched in hot water for 10min, and the extracts of the raw and blanched vegetables were prepared and used for subsequent analysis. The result revealed that all the vegetables inhibited acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activity as well as the pro-oxidants induced lipid peroxidation in rat brain in a dose dependent manner; however, Amarantus cruentus extract (EC50 = 97.9μg/ml) had the highest inhibitory effect on acetylcholinesterase activity while Telfairia occidentalis extract (EC50 = 52.7μg/ml) had the highest inhibitory effect on butyrylcholinesterase activity. However, blanching of the vegetables caused a significant (P < 0.05) decrease in the inhibitory effect of the vegetables on AChE activities while it enhanced the inhibition of the pro-oxidants induced lipid peroxidation in rat brain in vitro. Therefore, some of the possible mechanism by which green leafy vegetables exert their neuroprotective activities could be through the inhibition of acetylcholinesterase and butyrylcholinesterase activities and prevention of lipid peroxidation in the brain. However, blanching of the vegetables could reduce their ability to inhibit acetylcholinesterase and butyrylcholinesterase activity.

Inhibition of acetylcholinesterase activities and some pro-oxidant induced lipid peroxidation in rat brain by two varieties of ginger (Zingiber officinale).

Ginger has been reportedly used for the management or treatment of Alzheimer's disease in folklore medicine. Therefore, this study sought to investigate the inhibitory effects of water extractable phytochemicals of red and white ginger on acetylcholinesterase activities, and sodium nitroprusside (SNP) and quinolinic acid (QA)-induced lipid peroxidation in rat brain -in vitro. Both extracts inhibited acetylcholinesterase (AChE) activities in a dose-dependent manner; however, white ginger had higher acetylcholinesterase inhibitory activity than red ginger. Combination of the ginger inhibited acetylcholinesterase activities synergistically. Furthermore, SNP and QA caused a significant increase in the malondialdehyde (MDA) contents of the brain; however, the extracts significantly decrease the SNP and QA elevated brain MDA contents in a dose-dependent manner. Nevertheless, there was no significant difference (P>0.05) in the inhibition of the SNP and QA-induced lipid peroxidation by both extracts. The inhibitory effect of ginger extracts on acetylcholinesterase activities and some prooxidants induced lipid peroxidation in rat's brain could be attributed to the presence of phytochemicals such as flavonoids, tannins, alkaloids and terpenoids. Therefore, some possible mechanism by which ginger extracts exert anti-Alzheimer properties could be through the inhibition of acetylcholinesterase activities and prevention of lipid peroxidation in the brain.

Antioxidative Potential of Ocimum gratissimum and Ocimum canum Leaf Polyphenols and Protective Effects on Some Pro-Oxidants Induced Lipid Peroxidation in Rat Brain: An in vitro Study

Antioxidative Potential of Ocimum gratissimum and Ocimum canum Leaf Polyphenols and Protective Effects on Some Pro-Oxidants Induced Lipid Peroxidation in Rat Brain: An in vitro Study

Water extractable phytochemicals from Capsicum pubescens (tree pepper) inhibit lipid peroxidation induced by different pro-oxidant agents in brain: in vitro

This study seeks to determine the antioxidant and neuroprotective properties of aqueous extract of ripe and unripe Capsicum pubescens (tree pepper) on some pro-oxidant induced lipid peroxidation in rat’s brain (in vitro). The total phenol, vitamin C, ferric reducing antioxidant property (FRAP) and Fe (II) chelating ability of the extracts of C. pubescens were determined. Thereafter, the ability of the extracts to inhibit lipid peroxidation (induced by FeSO4, sodium nitroprusside or quinolinic acid) in rat’s brain homogenates (in vitro) was determined. The results of the study revealed that ripe C. pubescens had a significantly higher (P 0.05) in the vitamin C [ripe (231.5 μg/g), unripe (224.4 μg/g)] content and Fe (II) chelating ability of the extracts. However, both extracts significantly (P 0.05) inhibit Fe (II)/H2O2 induced decomposition of deoxyribose. It was therefore concluded that ripe and unripe C. pubescens would inhibit lipid peroxidation in rat brain in vitro. However, the ripe pepper was a more potent inhibitor of lipid peroxidation in the rat’s brain; this is probably due to its higher phenol content and reducing power.

Polyphenols in red pepper [Capsicum annuum var. aviculare (Tepin)] and their protective effect on some pro-oxidants induced lipid peroxidation in brain and liver

Polyphenols exhibit a wide range of biological effects because of their antioxidant properties. The study sought to carry out a comparative studies on the protective ability of free and bound polyphenol extracts of red Capsicum annuum var. aviculare (Tepin) on brain and liver – in vitro. Free polyphenols of red Capsicum annuum var. aviculare (Tepin) were extracted with 80% acetone, while the bound polyphenols were extracted with ethyl acetate from acid and alkaline hydrolysed residue from free polyphenols extract. The phenol content, Fe(II) chelating ability, OH radical scavenging ability and protective ability of the extract against some pro-oxidant (25 μM Fe(II), 7 μM sodium nitroprusside and 1 mM quinolinic acid)-induced lipid peroxidation in brain and liver was subsequently determined. The results of the study revealed that the free polyphenols (218.2 mg/100 g) content of the pepper were significantly higher (P<0.05) than the bound polyphenols (42.5 mg/100 g). Furthermore, the free polyphenol extract had a significantly higher (<0.05) Fe(II) chelating ability, OH radical scavenging ability than the bound polyphenols. In addition, both extracts significantly inhibited (P<0.05) basal and the various pro-oxidant (25 μM Fe(II), 7 μM sodium nitroprusside and 1 mM quinolinic acid)-induced lipid peroxidation in rat's brain and liver in a dose-dependent manner. However, the free polyphenols caused a significantly higher inhibition in the MDA (malondialdehyde) production in the brain and liver homogenates than the bound phenols. In conclusion, Capsicum annuum var. aviculare (Tepin) contains 83.7% free soluble polyphenol and 16.3% bound polyphenols. In addition, both polyphenolic extracts inhibit the various pro-oxidant agents (Fe2+, sodium nitroprusside and quinolinic acid) induced lipid peroxidation in brain and liver tissues in a doe-dependent manner. However, the free polyphenols had higher protective ability than the bound polyphenols. The main mechanism through which they are carry out their protective effect against lipid peroxidation in the brain and the liver is by Fe(II) chelating ability, OH and NO radicals scavenging ability and inhibition of over-stimulation of NMDA receptor.