Protective effects of lazaroids against oxygen-free radicals induced lysosomal damage

Lipid peroxidation of membranes by oxygen free radicals has been implicated in various disease states. Different antioxidants and iron chelators have been used to reduce lipid peroxidation. Lazaroids have been used for the acute treatment of central nervous system disorders such as trauma and ischemia wherein lipid peroxidative processes take place.In this study we evaluated the effect of lazaroids (U-785 18F and U-74389F) on the release of acid phosphatase activity and formation of malondialdehyde (MDA) in rat liver lyosomes subjected to exogenously generated oxygen free radicals. There was a significant increase in the acid phosphatase release and MDA formation in the presence of oxygen free radicals. This was prevented by both the lazaroids. In a separate study the effect of lazaroid U-74389F was seen on the zymosan-stimulated polymorphonuclear (PMN) leukocyte-derived chemiluminescence. The PMN leukocyte chemiluminescent activity was attenuated by the lazaroid in a dose-dependent manner. These studies suggest that lazaroids may inhibit lipid peroxidation and stabilize the membrane.     

Oxygen free radical producing activity of polymorphonuclear leukocytes in patients with Parkinson's disease

Oxygen free radicals (OFRs) have been suggested in the pathogenesis of Parkinson's disease (PD). These free radicals exert their cytotoxic effect by peroxidation of lipid membrane resulting in the formation of malondialdehyde (MDA). Polymorphonuclear (PMN) leukocyte is one of the major sources of OFR. However, the oxygen free radical producing activity of PMN leukocytes in patients with PD is not known. We therefore studied the oxygen free radical producing activity of polymorphonuclear leukocytes and MDA levels in the serum of healthy subjects and in patients with Parkinson's disease. The oxygen free radical producing activity of PMN leukocytes in blood and the MDA content in serum were significantly higher in patients with Parkinson's disease than in healthy subjects. These results indicate a possible role of oxygen free radicals in the pathogenesis of Parkinson's disease.     

Polymorphonuclear leukocytes-induced injury in hypoxic cardiac myocytes

Growing evidence suggests that free radicals derived from polymorphonuclear leukocytes (PMNs) play an important role in myocardial ischemia-reperfusion injury. To elucidate the cellular mechanism by which activated PMNs exacerbate ischemic myocardial damage, we investigated the extent of cell injury, assessed by the morphological deterioration, free radical generation, and lipid peroxidation in mouse embryo myocardial cells coincubated with activated PMNs. The generation of PMN-derived free radicals was related to the extent of myocardial cell injury. When myocardial cell sheets were subjected to hypoxia and glucose-free media, myocardial cells were injured (cristalysis in the mitochondria and disruption of the sarcolemma) after adding various PMN activators, and the injury extended to the adjacent cells. Chemiluminescent emission and production of thiobarbituric acid-reactive substances in the coincubated cells increased markedly compared with myocardial cells or PMNs alone. The augmented lipid peroxidation coincided with the progression of myocardial cell injury. Catalase inhibited the myocardial cell injury by 52%, the chemiluminescence by 46%, and lipid peroxidation by 50%, whereas superoxide dismutase exhibited less pronounced inhibition. These results indicate that a chain reaction of lipid peroxidation in myocardial cells induced by PMN-derived free radicals closely correlates with membrane damage and contributes to the propagation of irreversible myocardial cell damage.     

Changes in the fluorescence parameters of bound N-(1-pyrene) maleimide by lipid peroxidation of intestinal brush-border membranes

Using a fluorogenic thiol reagent, N-(1-pyrene)maleimide (NPM), we have examined of lipid peroxidation on the microenvironment around SH groups of the membrane proteins in porcine intestinal brush-border membrane vesicles. The lipid peroxidation of the membranes was performed with various concentrations of t-butylhydroperoxide (t-BuOOH) in the presence of 100 microM ascorbic acid and 10 microM Fe2+. Treatment of NPM-labeled membranes with these oxidizing agents resulted in a decrease of the fluorescence lifetime, suggesting modification of the environmental properties around the bound dye. Measurement of the steady-state fluorescence anisotropy of the labeled membranes indicated restriction of the motion of the bound dye by the lipid peroxidation membranes. This interpretation was further supported by an elevation of the transition temperature of the anisotropy, a decrease in the quenching rate constant of the fluorescence with acrylamide and a decrease in the SH reactivity of the membrane proteins for NPM by lipid peroxidation. Based on these results, the possibility of conformation changes in the vicinity of SH groups in the membrane proteins associated with lipid peroxidation has been discussed.     

Damage to human erythrocytes by radiation-generated HO* radicals: molecular changes in erythrocyte membranes

The effectiveness of radiation-generated HO

•

radicals in initiating erythrocyte hemolysis in the presence of oxygen and under anaerobic conditions and prehemolytic structural changes in the plasma-erythrocyte membrane were studied. Under anaerobic conditions the efficacy of HO

•

radicals in induction of hemolysis was 16-fold lower than under air. In both conditions, hemolysis was the final consequence of changes of the erythrocyte membrane. Preceding hemolysis, the dominating process under anaerobic conditions was the aggregation of membrane proteins. The aggregates were principally formed by -S-S- bridges. A decrease in spectrin and protein of band 3 content suggests their participation in the formation of the aggregates. These processes were accompanied by changes in protein conformation determined by means of 4-maleimido-2,2,6,6-tetramethylpiperidine-N-oxyl (MSL) spin label attached to membrane proteins. Under anaerobic conditions, in the range of prehemolytical doses, the reaction of HO

•

with lipids caused a slight (10-16%) increase in fluidity of the lipid bilayer in its hydrophobic region with a lack of lipid peroxidation. However, in the presence of oxygen, hemolysis was preceded by intense lipid peroxidation and by profound changes in the conformation of membrane proteins. At the radiation dose that normally initiates hemolysis a slight aggregation of proteins was observed. Changes were not observed in particular protein fractions. It can be suggested the cross-linking induced by HO

•

radicals under anaerobic conditions and a lack of lipid peroxidation are the cause of a decrease in erythrocyte sensitivity to hemolysis. Contrary, under aerobic conditions, molecular oxygen suppresses cross-linking, catalysing further steps of protein and lipid oxidation, which accelerate hemolysis.     

Advanced glycation end products (AGEs), free radicals and diabetes

Nonenzymatic glycation, i.e. binding of monosaccharides to amino groups of proteins, gives rise to complex components called "advanced glycation end-products" (AGEs), which alter protein structure and functions, and participate in diabetic long-term complications. Glycation and oxidative stress are closely linked, and are often referred to as "glycoxidation" processes. Experimental data support these interactions. a) All glycation steps generate oxygen free radicals, some of these steps being common with these of lipid peroxidation. b) AGEs bind to membrane receptors such as RAGE, and induce an oxidative stress and a pro-inflammatory status. c) Glycated proteins modulate cellular oxidative functions: glycated collagens induce an inappropriate oxidative response in PMNs. d) Products of lipid peroxidation (MDA) bind to proteins and amplify glycoxidation-induced damages. Glycoxydation intensity increases in diabetes mellitus, ageing, renal failure and other pathological states with oxidative stress. Therapies aiming at limiting glycoxidation take into account its oxidative part.     

Distinct temporal relation among oxygen uptake, malondialdehyde formation, and low-level chemiluminescence during microsomal lipid peroxidation

An oxystat system was employed in conjunction with a single-photon counting apparatus for simultaneous monitoring of oxygen uptake, oxidative decomposition of membrane lipids, and occurrence of electronically excited species during microsomal lipid peroxidation. During NADPH/ADP-iron-promoted lipid peroxidation at a steady state oxygen partial pressure (pO2) of 30 mm Hg, complex time relationships among oxygen uptake, malondialdehyde (MDA) formation, and low-level chemiluminescence were observed. While the first two parameters occurred nearly simultaneously, low-level chemiluminescence occurred with a significant delay. A decrease of the steady state pO2 to 3 mm Hg led to significant increases of the lag phases of all three parameters and a further enhancement of the time displacement of low-level chemiluminescence in relation to oxygen uptake and MDA formation. At a pO2 of 0.5 mm Hg, the lowest pO2 maintained during this study, no low-level chemiluminescence was observed while oxygen uptake and MDA formation were still detected. In contrast, during NADPH/CCl4-promoted lipid peroxidation at a pO2 of 0.5 mm Hg a sudden drastic rise of low-level chemiluminescence accompanying oxygen uptake and MDA formation was observed. At pO2 between 0.5 and 3 mm Hg all three parameters occurred nearly concomitantly during the entire incubation. At pO2 levels above 3 mm Hg all three parameters showed principally the same behavior. However, the respective maxima of low-level chemiluminescence were reached with some delay. The present observations support the assumption that the decomposition of membrane lipid peroxyl radicals to MDA and the formation of electronically excited species proceed via different pathways. The time displacement between oxygen uptake and MDA formation, on the one hand, and low-level chemiluminescence, on the other hand, depends on the type of initiating radical system and on the steady state pO2 level. It is suggested that the differences are due to distinct subsets (chemical or spatial) of secondary peroxyl radicals in the membrane.     

Effect of oxygen concentration on the formation of molondialdehyde-like material in a model of tissue ischemia and reoxygenation

This study was conducted to explore the functional relationship between oxygen concentration during tissue reoxygenation after ischemia and the extent of postischemic lipid peroxidation, an indicator of reoxygenation injury. Excised rat liver or kidney tissue was rendered ischemic for 1 h at 37°C, minced into 1 mm³ fragments, and then reoxygenated for 1 h in flasks of buffered salt solution containing various amounts of oxygen. Production of malondialdehyde-like material (MDA) was measured to indicate lipid peroxidation. MDA production was minimal at oxygen tensions less than 10 mmHg, increased sharply from 10 to 50 mmHg, and plateaued at approximately 100 mmHg. A similar functional relationship was produced by a simple mathematical model of free radical mediated lipid peroxidation in biological membranes, suggesting that MDA production is indeed caudes by free radical oxidation of membrane phospholipids and that the oxygen effect is governed by simple competition between chain propagation and chain termination reactions within the membrane. These experimental and analytical results confirm that relatively low concentrations of oxygen are sufficient to produce oxidative damage in post-ischemic tissues.     

Increase of the molecular rigidity of the protein conformation in the intestinal brush-border membranes by lipid peroxidation

The effect of lipid peroxidation on the protein conformation of the porcine intestinal brush-border membranes was studied using a fluorogenic thiol reagent, N-[7-dimethylamino-4-methylcoumarinyl]maleimide (DACM). By a kinetic analysis of the reaction of the membranes with DACM, it was shown that the reaction rate of the SH groups (SHf) of the membrane proteins, whose reaction with the dye is very fast, decreases in proportion to the extent of thiobarbituric acid-reactive substance formation. The difference in the rate of the reaction of the SHf groups for DACM between the control and peroxidized membranes completely disappeared after denaturation of the proteins by treatment with guanidine hydrochloride. The reaction of DACM with the SHf groups of the control membranes accelerated when the temperature was increased with an apparent transition temperature between 25 degrees C and 30 degrees C. On the other hand, no transition was observed in the peroxidized membranes over the temperature range 20-43 degrees C. These results suggest that the conformation around the SHf groups of the proteins in the peroxidized membranes is apparently different from that in the control membranes. A modification of the conformation around the SH groups in the membrane proteins associated with lipid peroxidation was further demonstrated by finding that the quenching efficiency of the fluorescence of the DACM-labeled membranes by Tl+ was markedly decreased after lipid peroxidation. Based on these results, changes in the protein conformation of the porcine intestinal brush-border membranes by lipid peroxidation are discussed.     

Different roles for nitrogen monoxide and peroxynitrite in lipid peroxidation induced by activated neutrophils

We studied the roles of nitrogen monoxide (NO&z.rad;) and peroxynitrite produced by the polymorphonuclear leukocytes (PMNs) isolated from an inflammatory exudate. PMNs were incubated either in a medium with a submicromolar concentration of iron or in a diethylenetriaminepenta-acetic acid (DTPA)-containing medium, and stimulated with phorbol 12-myristate 13-acetate (PMA) to generate free radicals. In both conditions superoxide anion (O(2)(*)(-)), NO&z.rad; and peroxynitrite were produced. In the presence of arachidonic acid, malondialdehyde (MDA) was generated. This MDA was generated in one of two way; the peroxynitrite iron-independent mechanism (40%) and the Fenton reaction, caused by free iron (60%). We also observed that the addition of L-arginine was followed by a 42% reduction in MDA, which can be explained by the antioxidant effect of NO&z.rad;. These results indicate that lipid peroxidation can occur in the absence of iron, through a peroxynitrite-mediated mechanism, and that NO&z.rad; may act as an antioxidant when it is produced in large amounts.     

Effect of factors of favism on the protein and lipid components of rat erythrocyte membrane

Erythrocytes prepared from riboflavin- and tocopherol-deficient (RT^?) and from control rats were used to investigate the mechanism of oxidative hemolysis by the factors of favism. RT^? erythrocytes have a defense system against the oxidative stress which is blocked either where regeneration of GSH occurs or the scavenging of the radicals from the membrane is prevented. The oxidative factors used were isouramil, divicine and diamide. When RT^? erythrocytes were treated with isouramil, GSH decreased to undetectable levels and was not regenerated. Complete hemolysis occurred, but no oxidation of SH groups of membrane proteins or formation of spectrin polymers was detected. A similar effect was observed with diamide. However, SH groups of membrane proteins were completely oxidized and spectrin polymers were formed. Extensive lipid peroxidation was also detected together with a 30% fall in the arachidonic acid level. Control erythrocytes treated with either isouramil or diamide were not hemolyzed. When treated with isouramil, after a fall in the first few minutes, the GSH level was completely regenerated after 20 min. Incubation with diamide caused extensive oxidation of SH groups of membrane proteins and formation of spectrin polymers. No lipid peroxidation was detected after treatment with isouramil, but the same decrease of arachidonic acid occurred as in RT^? erythrocytes. These results support the hypothesis that oxidative hemolysis by the factors of favism is caused by uncontrolled peroxidation of membrane lipids.     

Effect of polyethylene glycol on lipid peroxidation in cold-stored rat hepatocytes

A mechanism suggested to cause injury to preserved organs is the generation of oxygen free radicals either during the cold-storage period or after transplantation (reperfusion). Oxygen free radicals can cause peroxidation of lipids and alter the structural and functional properties of the cell membranes. Methods to suppress generation of oxygen free radicals of suppression of lipid peroxidation may lead to improved methods of organ preservation. In this study we determined how cold storage of rat hepatocytes affected lipid peroxidation by measuring thiobarbituric acid reactive products (malondialdehyde, MDA). Hepatocytes were stored in the UW solution +/- glutathione (GSH) or +/- polyethylene glycol (PEG) for up to 96 h and rewarmed (resuspended in a physiologically balanced saline solution and incubated at 37 degrees C under an atmosphere of oxygen) after each day of storage. Hepatocytes rewarmed after storage in the UW solution not containing PEG or GSH showed a nearly linear increase in MDA production with time of storage and contained 1.618 +/- 0.731 nmol MDA/mg protein after 96 h. When the storage solution contained PEG and GSH there was no significant increase in MDA production after up to 72 h of storage and at 96 h MDA was 0.827 +/- 0.564 nmol/mg protein. When freshly isolated hepatocytes were incubated (37 degrees C) in the presence of iron (160 microM) MDA formation was maximally stimulated (3.314 +/- 0.941 nmol/mg protein). When hepatocytes were stored in the presence of PEG there was a decrease in the capability of iron to maximally stimulate lipid peroxidation. The decrease in iron-stimulated MDA production was dependent upon the time of storage in PEG (1.773 nmol/mg protein at 24 h and 0.752 nmol/mg protein at 48 h).(ABSTRACT TRUNCATED AT 250 WORDS)     

Altered cellular membrane fluidity levels and lipid peroxidation during experimental pancreas transplantation

Although the pathogenesis of ischemia reperfusion (IR) injury is based on complex mechanisms, free radicals play a central role. We evaluated membrane fluidity and lipid peroxidation during pancreas transplantation (PT) performed in 12 pigs (six donors and six recipients). Fluidity was measured by fluorescence spectroscopy, and malondialdehyde (MDA) and 4-hydroxyalkenals (4-HDA) concentrations were used as an index of lipid oxidation. Pancreatic tissues were collected as follows: (A) donor, immediately before vascular clamping; (B) graft, following perfusion lavage with University of Wisconsin preservation fluid; (C) graft, after 16?h of cold ischemia; and (D) recipient, 30?min vascular postreperfusion. Fluidity and MDA and 4-HDA concentrations were similar in cases A, B, and C. However, there was significant membrane rigidity and increased lipid peroxidation after reperfusion (D). These findings suggest that reperfusion exaggerates oxidative damage and may account for the rigidity in the membranes of allografts during PT.     

水分胁迫对甘蔗叶片线粒体膜流动性的影响及其与膜脂过氧化的关系

用荧光探剂ANS对抗旱性不同的甘蔗品种在水分胁迫下叶片线粒体膜流动性的变化进行的研究表明,水分胁迫降低了线粒体膜的流动性,抗旱性强的甘蔗品种Co 617和F.Y.79-9的下降幅度分别小于抗旱性弱的Co 740和M.T.77-208;水分胁迫下线粒体膜流动性的下降与膜脂过氧化产物丙二醛含量的增加有密切关系。外源自由基处理试验也表明,甘蔗叶片线粒体膜流动性的下降与膜脂过氧化作用有关。     

The induction of lipid peroxidation in liposomal membrane by ultrasound and the role of hydroxyl radicals

Ultrasonic radiation produced a dose-dependent linear increase in lipid peroxidation in the liposomal membrane as reflected in the measurements of conjugated dienes, lipid hydroperoxides, and malondialdehydes (MDA). Production of MDA was confirmed by spectrophotometric and spectrofluorometric methods including the detection of excitation (360 nm) and emission (435 nm) maxima characteristic of the MDA-glycine adduct formed after addition of glycine in the system. Ultrasound of frequencies 20 kHz (used for laboratory purposes) and 3.5 MHz (used for clinical purposes) produced MDA in an identical manner. Ultrasound-induced lipid peroxidation was enhanced synergistically by 2.5 X 10(2) microM ascorbic acid but inhibited significantly by 10(4) microM ascorbic acid. Ultrasound-induced production of MDA could not be inhibited to any significant degree by superoxide dismutase, histidine, dimethylfuran, or beta-carotene but was very significantly inhibited by cholesterol (93%), butylated hydroxytoluene (88%), alpha-tocopherol (85%), sodium benzoate (80%), dimethyl sulfoxide (80%), sodium formate (64%), and EDTA (64%). The scavenger studies indicated the functional role of OH radicals in the initiation of ultrasound-induced lipid peroxidation.     

5-methoxytryptophol preserves hepatic microsomal membrane fluidity during oxidative stress

Lipid peroxidation is a degenerative chain reaction in biological membranes that may be initiated by exposure to free radicals. This process is associated with changes in the membrane fluidity and loss of several cell membrane-dependent functions. 5-methoxytryptophol (ML) is an indole isolated from the mammalian pineal gland. The purpose of this study was to investigate the effects of ML (0. 01mM-10mM) on membrane fluidity modulated by lipid peroxidation. Hepatic microsomes obtained from rats were incubated with or without ML (0.01-10 mM). Then lipid peroxidation was induced by FeCl(3), ADP, and NADPH. Membrane fluidity was determined using fluorescence spectroscopy. Malonaldehyde (MDA) +4-hydroxyalkenals (4-HDA) concentrations were estimated as an indicator of the degree of lipid peroxidation. With oxidative stress, membrane fluidity decreased and MDA+4-HDA levels increased. ML (0.01-3 mM) reduced membrane rigidity and the rise in MDA+4-HDA formation in a concentration-dependent manner. 10 mM ML protected against lipid peroxidation but failed to prevent the membrane rigidity. In the absence of oxidative reagents, ML (0.3-10 mM) decreased membrane fluidity whereas MDA+4-HDA levels remained unchanged. This indicates that ML may interact with membrane lipids. The results presented here suggest that ML may be another pineal indoleamine (in addition to melatonin) that resists membrane rigidity due to lipid peroxidation.     

Quinone formation from carcinogenic benzo[a]pyrene mediated by lipid peroxidation in phosphatidylcholine liposomes

The behavior of benzo[a]pyrene (B[a]P) during peroxidation of phosphatidylcholine (PC) liposomes initiated by an azo compound was investigated to examine the mechanism of quinone formation from carcinogenic B[a]P mediated by nonenzymatic lipid peroxidation occurring in vivo. B[a]P had a retarding effect on the peroxidation of polyunsaturated fatty acid moiety of PC. The major oxidation products which accumulated in the peroxidized liposomes were B[a]P 1,6-, 3,6-, and 6,12-quinone. Antioxidants acting as scavengers of chain-propagating lipid peroxy radicals effectively prevented not only lipid peroxidation but also B[a]P oxidation in the liposomal suspension. PC hydroperoxides, the primary products of PC oxidation, did not react with B[a]P in the absence of the azo compound, indicating that lipid peroxy radicals, not lipid hydroperoxides, are responsible for the formation of these quinones. The experiments using 18O2 gas and 18O-labeled methyl linoleate hydroperoxides demonstrated that B[a]P quinones are formed by incorporating molecular oxygen and their origin is partly due to the lipid peroxy radical. The mechanism proposed for the formation of B[a]P quinones mediated by peroxidation of membrane lipids involves a direct attack of the lipid peroxy radical on B[a]P and subsequent autocatalytic oxidation. Weak carcinogenic and noncarcinogenic pentacyclic aromatic hydrocarbons showed little reactivity to the lipid peroxy radical in the liposomes. Thus, the facility of the peroxidative attack on B[a]P may be related to the powerful carcinogenic activity of this substance.     

Effects of endotoxin on oxidative metabolism of polymorphonuclear leukocytes

The influence of endotoxin on rat polymorphonuclear leucocytes (PMN) ability to generate oxygen free radicals (OFR) has been studied by chemiluminescence method. PMNs derived from intact animals were used as a control. PMNs derived from animals with 1.5 h endotoxemia increased OFR production after stimulation by latex. In contrast, PMNs derived from intact animals and preincubated with endotoxin for 1.5 h decreased OFR production after stimulation bw latex. It was proposed that stimulating effect of endotoxin on PMNs in vivo was mediated by plasma components.     

Membrane lipid peroxidation by UV-A: mechanism and implications

UV-A produced a dose-dependent linear increase of lipid peroxidation in liposomal membrane, as detected by the assay of (i) conjugated dienes, (ii) lipid hydroperoxides, (iii) malondialdehydes (MDA), and (iv) the fluorescent adducts formed by the reaction of MDA with glycine and also a linear dose-dependent increase of [14C]glucose efflux from the liposomes. UV-A-induced MDA production could not be inhibited by any significant degree by sodium formate, dimethyl sulfoxide, EDTA, or superoxide dismutase but was very significantly inhibited by butylated hydroxytoluene, alpha-tocopherol, sodium azide, L-histidine, dimethylfuran, and beta-carotene. MDA formation increased with an increase in the D2O content in water, leading to a maximal amount of nearly 50% enhancement of lipid peroxidation in 100% D2O vis-à-vis water used as dispersion medium. The experimental findings indicate the involvement of singlet oxygen as the initiator of the UV-A-induced lipid peroxidation.     

Ischemia-reperfusion leads to depletion of glutathione content and augmentation of malondialdehyde production in the rat heart from overproduction of oxidants: Can caffeic acid phenethyl ester (CAPE) protect the heart?

During restoration of blood flow of the ischemic heart induced by coronary occlusion, free radicals cause lipid peroxidation with myocardial injury. Lipid peroxidation end-products, such as malondialdehyde (MDA), have been used to assess oxygen free radical-mediated injury of the ischemic-reperfused (I/R) myocardium in rats. This experimental study assessed the preventive effect of caffeic acid phenthyl ester (CAPE), antioxidant, on I/R-induced lipid peroxidation in the rat heart. We are also interested in the role of CAPE on glutathione (GSH) levels, an antioxidant whose levels are influenced by oxidative stress. I/R leads to the depletion of GSH which is the major intracellular nonprotein sulphydryl and plays an important role in the maintenance of cellular proteins and lipid in their functional state and acts primarily to protect these important structures against the threat of oxidation. In addition, we also examined morphologic changes in the heart by using light microscopy. The left coronary artery was occluded for 30 min and then reperfused for 120 min more before the experiment was terminated. CAPE (50 M kg^–1) was administered 10 min prior to ischemia and during occlusion by infusion. At the end of the reperfusion period, rats were sacrificed, and the heart was quickly removed for biochemical determination and histopathological analysis. I/R was accompanied by a significant increase in MDA production and decrease in GSH content in the rat heart. Administration of CAPE reduced MDA production and prevented depletion of GSH content. These beneficial changes in these biochemical parameters were also associated with parallel changes in histopathological appearance. These findings imply that I/R plays a causal role in heart injury due to overproduction of oxygen radicals or insufficient antioxidant and CAPE exert cardioprotective effects probably by the radical scavenging and antioxidant activities.