Bor-Jen Lee: wt. This article has been cited by other articles in PMC. Abstract Background Cardiovascular disease is the leading cause of death worldwide. Higher oxidative stress may contribute to the pathogenesis of coronary artery disease CAD. Methods We enrolled 47 CAD patients in the study.
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Full Text Life Sciences 78 — www. In this study, the antioxidant activity of l-carnitine was investigated as in vitro. The antioxidant properties of the l-carnitine were evaluated by using different antioxidant assays such as 1, 1-diphenylpicryl-hydrazyl free radical DPPHI scavenging, total antioxidant activity, reducing power, superoxide anion radical scavenging, hydrogen peroxide scavenging and metal chelating activities.
Total antioxidant activity was measured according to ferric thiocyanate method. In addition, l-carnitine had an effective DPPHI scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, total reducing power and metal chelating on ferrous ions activities.
Also, those various antioxidant activities were compared to a-tocopherol and trolox as references antioxidants. D Elsevier Inc. All rights reserved. Keywords: DPPHI; Antioxidant activity; l-carnitine; Metal chelating; Reducing power; Radical scavenging Introduction l-carnitine 4-N-trimethylammoniumhydroxybutyric acid plays important physiological roles shuttling the long-chain fatty acids across the inner mitochondrial membrane for hoxidation and ATP production in peripheral tissues.
It translocates acetyl-Co-A into cytoplasm during acetyl-lcarnitine transport out of mitochondria. Despite the low level of h-oxidation in brain, l-carnitine is actively transported through the blood — brain barrier and accumulates in neural cells Shug et al.
As hypothesized Shug et al. The importance of reactive oxygen species and free radicals has attracted increasing attention over the past decade.
ROS are continuously produced during normal physiologic events and they can easily initiate the peroxidation of membrane lipids, leading to the accumulation of lipid peroxides. However, they are removed by antioxidant defence mechanisms. ROS are formed when endogenous antioxidant defences are inadequate. The imbalance between ROS and antioxidant defence mechanisms leads to oxidative modification in cellular membrane or intracellular molecules Duh et al.
A large amount of oxygen is consumed in this reaction and ATP is synthesized in the steps of electron transport chain and oxidative phosphorylation. Antioxidants can protect the human body from free radicals and ROS effects and retard the progress of many chronic diseases as well as lipid peroxidation Pryor, ; Kinsella et al. The most commonly used antioxidants at the present time are butylated hydroxyanisole BHA , butylated hydroxytoluene BHT , propyl gallate and tert-butylhydroquinone.
Therefore, there is a growing interest on natural additives as potential antioxidants. Grice, ; Moure et al. Also, l-carnitine has a protective effect on the activity of mitochondrial enzyme succinate dehydrogenase as well as the activity of the antioxidant enzymes, catalase and superoxide dismutase against 3-NPA-induced neurotoxicity Binienda and Ali, The antioxidant defense system is composed of mainly three enzymes; glutathione peroxidase, catalase, and superoxide dismutase.
Moreover, it can be implemented to minimize age-associated disorders, which free radicals are the major cause Kalaiselvi and Panneerselvam, In addition, recent studies have shown that acetyl-l-carnitine, one of the short-chain acyl esters, enhances learning capacity in aging animals Ando et al. Moreover, Yasuia and co-workers demonsterated that acetyl- l-carnitine has an antioxidant activity towards oxidative stress and that the improvement in cognitive ability seen with acetyl-l-carnitine may occur through an amelioration of cellular dysfunction via an inhibition of the increase in lipid hydroperoxidation observed in the brain tissue of untreated senescence-acceleration-prone mice Yasuia et al.
In this study, we evaluated the possible antioxidant effects of l-carnitine in different in vitro antioxidant assays including 1, 1-diphenylpicryl-hydrazyl free radical scavenging, total antioxidant activity by ferric thiocyanate method, reducing power, superoxide anion radical scavenging, hydrogen peroxide scavenging and metal chelating activities.
Ammonium thiocyanate was purchased from Merck. All other chemicals used were in analytical grade and obtained from either Sigma-Aldrich or Merck. Total antioxidant activity determination by ferric thiocyanate method The antioxidant activity of l-carnitine and standards was determined according to the ferric thiocyanate method Mitsuda et al. Therefore, 5 mL of linoleic acid emulsion contained On the other hand, 5 mL control was composed of 2. The mixed solution 5 mL was incubated at 37 -C in glass flask.
The peroxide level was determined by reading the absorbance at nm in a spectrophotometer II, Bio-Crom GmbH, Zurich, Switzerland after reaction with FeCl2 and thiocyanate at intervals during incubation. The latter ions form a complex with thiocyanate and this complex has a maximum absorbance at nm. This step was repeated every 5 h until the control reached its maximum absorbance value.
Therefore, high absorbance indicates high linoleic acid emulsion oxidation. All data on total antioxidant activity are the average of duplicate experimetns. Total reduction capability The samples prepared for ferric thiocyanate method were used for this and the other assays. The reducing power of lcarnitine was determined by the method of Oyaizu The mixture was incubated at 50 -C for 20 min. Aliquots 2. The upper layer of solution 2. Increased absorbance of the reaction mixture indicates an increase of reduction capability.
Ferrous metal ions chelating activity The chelating of ferrous ions by l-carnitine and standards was estimated by the method of Dinis et al. The reaction was initiated by the addition of 5 mM ferrozine 0. Then, the mixture was shaken vigorously and left at room temperature for ten minutes. Absorbance of the solution was then measured spectrophotometrically at nm.
Hydrogen peroxide scavenging activity The hydrogen peroxide scavenging ability of l-carnitine was determined according to the method of Ruch et al. A solution of H2O2 40 mM was prepared in phosphate buffer pH 7. The absorbance value of the reaction mixture was recorded at nm. Blank solution was containing the phosphate buffer without H2O2. This activity was measured by following the methodology described by Blois wherein the bleaching rate of a stable free radical, DPPH is monitored at a characteristic wavelength in the presence of the sample.
In its radical form, DPPHI absorbs at nm, but upon reduction by an antioxidant or a radical species its absorption decreases. Briefly, 0. Thirty minutes later, the absorbance was measured at nm. Lower absorbance of the reaction mixture indicates higher free radical scavenging activity. The DPPH concentration mM in the reaction medium was calculated from the calibration curve determined by linear regression R 2 : 0.
Superoxide anion radical scavenging activity Measurement of superoxide anion scavenging activity of lcarnitine was based on the method described by Liu et al. The reaction mixture was incubated at 25 -C for 5 min and the absorbance at nm was measured against blank samples. Decreased absorbance of the reaction mixture indicates increased superoxide anion scavenging activity. Statistical analysis All data on total antioxidant activity are the average of duplicate analyses.
The other analyses were performed in triplicate. The energy calculations were performed using the Spartan 04 Version 1. Results and discussion l-carnitine is an antioxidant and prevents the accumulation of end products of lipidoxidation Fabriello and Calabrese, ; Lowitt et al.
It is synthesized from two essential amino acids, lysine and methionine. In addition, carnitine is transported to skeletal and cardiac muscles after its major production in liver and kidney, and it transports acyl-CoA acids into the mitochondrial matrix for h-oxidation of free fatty acids Brevetti and Perna, ; Visioli et al.
Many studies have shown that natural antioxidants are closely related to their biofunctionalities, such as the reduction of chronic diseases like DNA damage, mutagenesis, carcinogenesis and inhibition of pathogenic bacteria growth which is often associated with the termination of free radical propagation in biological systems Covacci et al.
Thus, antioxidant capacity is widely used as a parameter for medicinal bioactive components. In this study, the antioxidant activity of the l-carnitine was compared to atocopherol and its water-soluble analogue trolox. The antioxidant activity of the l-carnitine, a-tocopherol and trolox has been evaluated in a series of in vitro tests: 1, 1-diphenylpicryl-hydrazyl free radical scavenging, ferric thiocyanate method, reducing power, scavenging of superoxide anion radical-generated non-enzymatic system, hydrogen peroxide scavenging and metal chelating activities.
Total antioxidant activity of l-carnitine, a-tocopherol and trolox was determined by the 0.
Antioxidant and antiradical activities of l -carnitine
Full Text Life Sciences 78 — www. In this study, the antioxidant activity of l-carnitine was investigated as in vitro. The antioxidant properties of the l-carnitine were evaluated by using different antioxidant assays such as 1, 1-diphenylpicryl-hydrazyl free radical DPPHI scavenging, total antioxidant activity, reducing power, superoxide anion radical scavenging, hydrogen peroxide scavenging and metal chelating activities. Total antioxidant activity was measured according to ferric thiocyanate method. In addition, l-carnitine had an effective DPPHI scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, total reducing power and metal chelating on ferrous ions activities.
Antioxidant and antiradical activities of L-carnitine.
Vugrel Antioxidant and antiradical activities of L-carnitine. Prevention of cytotoxicity and inhibition of intracellular communication by antioxidant catechins isolated from Chinese green tea. Lebensmittel Wissenchaft und-Technologie 32, — Antiradidal the low level of h-oxidation in brain, l-carnitine is actively transported through the blood — brain barrier and accumulates in neural cells Shug et al. It is widely acknowledged that the excessive reactive oxygen species ros or l-carnktine nitrogen species rns induced oxidative stress will cause significant damage to cell structure and biomolecular function, directly or indirectly leading to a number of diseases. Asteraceaea potential acaricide plant species. Antioxidant determinations by the use of a stable free radical. Antioxidant and antiradical activities of l-carnitine pdf At different concentrations, l-carnitine showed an effective reducing power Fig.
ANTIOXIDANT AND ANTIRADICAL ACTIVITIES OF L-CARNITINE PDF
Thus, removing hydrogen peroxide as well as superoxide anion is very important for protection of farmaceutical and food systems. Journal of Natural Products activihies, — However, they are removed by antioxidant defence mechanisms. Journal of Agricultural and Food Chemistry 49, — Moreover, it can be implemented to minimize age-associated disorders, which free radicals are the major cause Kalaiselvi and Panneerselvam, Scavenging effect of methanolic extract of peanut hulls on free radical and active oxygen species. From Antioxidant Action to Vitagene Regulation.