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Fulltext Evidence in support of potential applications of lipid peroxidation products in cancer treatment

Erejuwa OO, Sulaiman SA, Ab Wahab MS

Oxid Med Cell Longev, 2013;2013:931251.
PMID: 24369491 DOI: 10.1155/2013/931251

Cancer cells generate reactive oxygen species (ROS) resulting from mitochondrial dysfunction, stimulation of oncogenes, abnormal metabolism, and aggravated inflammatory activities. Available evidence also suggests that cancer cells depend on intrinsic ROS level for proliferation and survival. Both physiological and pathophysiological roles have been ascribed to ROS which cause lipid peroxidation. In spite of their injurious effects, the ROS and the resulting lipid peroxidation products could be beneficial in cancer treatment. This review presents research findings suggesting that ROS and the resulting lipid peroxidation products could be utilized to inhibit cancer growth or induce cancer cell death. It also underscores the potential of lipid peroxidation products to potentiate the antitumor effect of other anticancer agents. The review also highlights evidence demonstrating other potential applications of lipid peroxidation products in cancer treatment. These include the prospect of lipid peroxidation products as a diagnostic tool to predict the chances of cancer recurrence, to monitor treatment progress or how well cancer patients respond to therapy. Further and detailed research is required on how best to successfully, effectively, and selectively target cancer cells in humans using lipid peroxidation products. This may prove to be an important strategy to complement current treatment regimens for cancer patients.

Matched MeSH terms: Lipid Peroxidation*
Fulltext Palm olein oil produces less lipid peroxidation products than soya bean oil

Zaiton Z, Merican Z, Khalid BA, Mohamed JB, Baharom S

Asia Pac J Clin Nutr, 1997 Jun;6(2):116-8.
PMID: 24394713

The soleus muscles of hyperthyroid rats were used to investigate the effect of palm olein oil and soya bean oil on the production of lipid peroxidation products. It was found that palm olein oil but not soya bean oil significantly decreased malonaldehyde and conjugated diene levels of the soleus muscles of hyperthyroid rats. These findings suggest that palm olein per se produces less lipid peroxidation products than soya bean oil. Such an assay method gives a composite net picture of the propensity of an oil to produce lipid peroxidation products.

Matched MeSH terms: Lipid Peroxidation
Effect of docosahexanoic acid on quality of frozen-thawed bull semen in BioXcell extender

Kaka A, Haron W, Yusoff R, Yimer N, Khumran AM, Sarsaifi K, et al.

Reprod Fertil Dev, 2017 Mar;29(3):490-495.
PMID: 28442061 DOI: 10.1071/RD15089

This study was conducted to investigate the effect of docosahexanoic acid (DHA) supplementation in BioXcell extender on the quality of frozen-thawed bull semen. Twenty-four ejaculates were collected from three bulls (eight from each bull). Ejaculates with motility ≥70% and normal morphology ≥80% were extended into BioXcell extender to which 0 (control), 3, 5, 10 or 15ngmL(-1) DHA was added. The supplemented semen samples were incubated at 37°C for 15min for DHA uptake by spermatozoa. Later, samples were cooled for 2h at 5°C and packaged into 0.25-mL straws, frozen in liquid nitrogen for 24h and subsequently thawed for evaluation. Results are presented as percentages ± s.e.m. Supplementation with DHA at 3ngmL(-1) significantly improved sperm functional parameters including sperm motility, normal morphology, viability, acrosome integrity and membrane integrity when compared with other supplemented groups and the control. Lipid peroxidation increased as the incorporation of DHA supplementation increased. In conclusion, 3ngmL(-1) concentration of DHA resulted in superior quality of frozen-thawed bull spermatozoa and is suggested as the optimum level of DHA to be added into BioXcell extender.

Matched MeSH terms: Lipid Peroxidation
Fulltext Impact of sea-salt on morpho-physiological and biochemical responses in banana (Musa acuminata cv. Berangan)

Mazumdar P, Lau SE, Singh P, Takhtgahi HM, Harikrishna JA

Physiol Mol Biol Plants, 2019 May;25(3):713-726.
PMID: 31168234 DOI: 10.1007/s12298-019-00659-3

Banana is often grown in coastal-regions, and while known for its sensitivity towards seawater, little is documented on the effect of sea-salt on the growth, physiology and metal homeostasis. Here we report that banana plantlets exposed to sea-salt at extreme (average seawater concentration; 52.7 dS m-1), severe (28.5 dS m-1) or moderate (10.2 dS m-1) salinity levels had reduced root length (2.0-6.0-fold), plant height (1.2-1.6-fold), leaf number (2.0-2.3-fold) and leaf area (3.3-4.0-fold) compared to control plantlets. Degradation of pigments (total chlorophyll: 1.3-12.3-fold, chlorophyll a: 1.3-9.2-fold; chlorophyll b: 1.3-6.9-fold lower and carotenoids: 1.4-3.7-fold lower) reflected vulnerability of photosystems to salt stress. Relative water content showed a maximum decrease of 1.5-fold in salt stress. MDA analysis showed sea-salt exposure triggers 2.3-3.5-fold higher lipid peroxidation. Metal content analysis showed a 73-fold higher Na value from roots exposed to extreme salinity compared to control plantlets. While phenotype was clearly affected, moderate salinity showed no significant alteration of macro (N, P, K and Ca) and micro (Fe, Mn and Cu) metal content. The antioxidant enzymes: SOD (3.2-fold), CAT (1.7-fold) and GR (6-fold) showed higher activity at moderate salinity level compared to control plantlets but lower activity at severe (SOD: 1.3-fold; CAT: 1.5-fold; GR: 2-fold lower) and extreme seawater salinity (SOD: 1.5; CAT: 1.9; GR: 1.3-fold lower). Mild changes in growth and physiology at sea-salt levels equivalent to moderate seawater flooding, indicate that banana will survive such flooding, while extreme seawater inundation will be lethal. This data provides a reference for future salinity-mediated work in banana.

Matched MeSH terms: Lipid Peroxidation
Lipid peroxidation: Its effects on the formulation and use of pharmaceutical emulsions

Khanum R, Thevanayagam H

Asian J Pharm Sci, 2017 Sep;12(5):401-411.
PMID: 32104352 DOI: 10.1016/j.ajps.2017.05.003

Pharmaceutical delivery systems are developed to improve the physicochemical properties of therapeutic compounds. Emulsions are one of these drug delivering systems formulated using water, oils and lipids as main ingredients. Extensive data are usually generated on the physical and chemical characteristics of these oil-in-water and lipid emulsions. However, the oxidative tendency of emulsions is often overlooked. Oxidation impacts the overall quality and safety of these pharmaceutical emulsions. Additionally, introducing oxidatively unstable emulsions into biological systems further promotes oxidation in situ. Products of these reactions then continue to pose serious harm to cells and fuel other physiological oxidation reactions. Consequently, the increase of oxidation products leads to oxidative damage to biological systems. Thus, emulsions with lower lipid peroxidation are more stable and will reduce the negative effects of oxidation in situ. Preventive measures during the formulation of emulsions are important. Many naturally occurring and cost effective substances possess low oxidation tendencies and confer oxidative protection when used in emulsions. Additionally, certain preparatory methods should be employed to reduce or better control lipid peroxidation. Finally, emulsions must be evaluated for their oxidation susceptibility using the various techniques available. Careful attention to the preparation of emulsions and assessment of their oxidative stability will help produce safer emulsions without compromising efficacy.

Matched MeSH terms: Lipid Peroxidation
Fulltext Effects of tocotrienol supplementation on hair growth in human volunteers

Beoy LA, Woei WJ, Hay YK

Trop Life Sci Res, 2010 Dec;21(2):91-9.
PMID: 24575202 MyJurnal

Studies have shown an association between oxidative stress and alopecia. Patients with alopecia generally exhibit lower levels of antioxidants in their scalp area as well as a higher lipid peroxidation index. Tocotrienols belong to the vitamin E family and are known to be potent antioxidants. Hence, a study was conducted to investigate the effect of tocotrienol supplementation on hair growth in volunteers suffering from hair loss. Twenty one volunteers were randomly assigned to orally receive 100 mg of mixed tocotrienols daily while 17 volunteers were assigned to receive placebo capsule orally. The volunteers were monitored for the number of hairs in a pre-determined scalp area as well as the weight of 20 strands of 1 cm length hair clippings at 0 (before supplementation), 4 and 8 months. The number of hairs of the volunteers in the tocotrienol supplementation group increased significantly as compared to the placebo group, with the former recording a 34.5% increase at the end of the 8-month supplementation as compared to a 0.1% decrease for the latter. Nevertheless, the cumulative weight of 20 strands of hair clippings did not differ much from the baseline for both supplementation groups at the end of the study period. In conclusion, this trial demonstrated that supplementation with tocotrienol capsules increases hair number in volunteers suffering from hair loss as compared to the placebo group. This observed effect was most likely to be due to the antioxidant activity of tocotrienols that helped to reduce lipid peroxidation and oxidative stress in the scalp, which are reported to be associated with alopecia.

Matched MeSH terms: Lipid Peroxidation
Ferroptosis as a potential target for cancer therapy

Chen Z, Wang W, Abdul Razak SR, Han T, Ahmad NH, Li X

Cell Death Dis, 2023 Jul 24;14(7):460.
PMID: 37488128 DOI: 10.1038/s41419-023-05930-w

Ferroptosis is a recently discovered essential type of cell death that is mainly characterized by iron overload and lipid peroxidation. Emerging evidence suggests that ferroptosis is a double-edged sword in human cancer. However, the precise underlying molecular mechanisms and their differential roles in tumorigenesis are unclear. Therefore, in this review, we summarize and briefly present the key pathways of ferroptosis, paying special attention to the regulation of ferroptosis as well as its dual role as an oncogenic and as a tumor suppressor event in various human cancers. Moreover, multiple pharmacological ferroptosis activators are summarized, and the prospect of targeting ferroptosis in cancer therapy is further elucidated.

Matched MeSH terms: Lipid Peroxidation
Fulltext Effect of single-session aerobic exercise with varying intensities on lipid peroxidation and muscle-damage markers in sedentary males

Moflehi D, Kok LY, Tengku-Kamalden TF, Amri S

Glob J Health Sci, 2012 Jul;4(4):48-54.
PMID: 22980341 DOI: 10.5539/gjhs.v4n4p48

This study was conducted to evaluate the effect of the different intensity levels of single-session aerobic exercise on serum levels of lipid peroxidation and muscle damage markers in sedentary males.

Matched MeSH terms: Lipid Peroxidation/physiology*
Fulltext Antioxidant and hepatoprotective effects of Murdannia bracteata methanol extract

Yam MF, Ang LF, Lim CP, Ameer OZ, Salman IM, Ahmad M, et al.

J Acupunct Meridian Stud, 2010 Sep;3(3):197-202.
PMID: 20869021 DOI: 10.1016/S2005-2901(10)60036-2

Murdannia bracteata (C. B. Clarke) is a local plant that is widely used in Malaysia as a traditional remedy for various diseases of the kidney and liver, including inflammation and cancer. In the present study, we investigated the antioxidant and hepatoprotective activities of M. bracteata methanol extract (MB). 2,2'-diphenyl-1-picrylhydrazyl radical scavenging activity, lipid peroxidation inhibition and trolox equivalent antioxidant capacity of MB were determined. The hepatoprotective activity of MB was studied using a CCl(4)-induced liver toxicity model in rats. The hepatoprotective effect was assessed by monitoring the plasma malondialdehyde level and serum alanine transaminase and aspartate transaminase activities. Histopathological changes of hepatic tissue were also investigated. The results indicated that MB possessed potential antioxidant, lipid peroxidation inhibition and free radical scavenging activities. Pretreatment of rats with MB (500 mg/kg and 1000 mg/kg per os) before induction of CCl(4)-induced hepatotoxicity showed a dose-dependent reduction in the necrotic changes in hepatic tissue. The increases in plasma malondialdehyde level, serum alanine transaminase and aspartate transaminase activities were also significantly inhibited by MB. The total phenolic content of MB determined using Folin-Ciocalteu assay was found to be 10%. The results of the present study indicated that the hepatoprotective effect of MB is most likely due to its antioxidant and free radical scavenging properties.

Matched MeSH terms: Lipid Peroxidation/drug effects
Fulltext Biomedical studies on lipid peroxidation and erythrocyte fragility during the process of aging

Kumar A

Asian Pac J Trop Biomed, 2011 Jan;1(1):6-7.
PMID: 23569715 DOI: 10.1016/S2221-1691(11)60058-0

To investigate oxidative stress, hemoglobin percentage and erythrocyte osmotic fragility in various aging groups.

Matched MeSH terms: Lipid Peroxidation/physiology*
The antioxidant properties of garlic compounds: allyl cysteine, alliin, allicin, and allyl disulfide

Chung LY

J Med Food, 2006;9(2):205-13.
PMID: 16822206

Garlic and garlic extracts, through their antioxidant activities, have been reported to provide protection against free radical damage in the body. This study investigated antioxidant properties of garlic compounds representing the four main chemical classes, alliin, allyl cysteine, allyl disulfide, and allicin, prepared by chemical synthesis or purification. Alliin scavenged superoxide, while allyl cysteine and allyl disulfide did not react with superoxide. Allicin suppressed the formation of superoxide by the xanthine/xanthine oxidase system, probably via a thiol exchange mechanism. Alliin, allyl cysteine, and allyl disulfide all scavenged hydroxyl radicals; the rate constants calculated based on deoxyribose competitive assay were 1.4-1.7 x 10(10), 2.1-2.2 x 10(9), and 0.7-1.5 x 10(10) M (1) second(1), respectively. Contrary to previous reports, allicin did not exhibit hydroxyl radical scavenging activity in this study. Alliin, allicin, and allyl cysteine did not prevent induced microsomal lipid peroxidation, but both alliin and allyl cysteine were hydroxyl scavengers, and allyl disulfide was a lipid peroxidation terminator. In summary, our findings indicated that allyl disulfide, alliin, allicin, and allyl cysteine exhibit different patterns of antioxidant activities as protective compounds against free radical damage.

Matched MeSH terms: Lipid Peroxidation/drug effects
Fulltext Alteration of lipid peroxidation and antioxidant enzymes in young Malaysian IDDM patients

Indran M, Rokiah P, Chan SP, Kuppusamy UR

Med J Malaysia, 2004 Jun;59(2):166-70.
PMID: 15559165 MyJurnal

The present study was designed to explore the relationship between lipid peroxidation and antioxidant enzymes in young Malaysian insulin dependant diabetes mellitus (IDDM) patients. Indicative parameters of lipid peroxidation, activities of antioxidant enzymes and diabetes parameters were evaluated in single blood samples from 30 young type 1 diabetic patients and 30 healthy control subjects. Antioxidant enzymes namely superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) were significantly decreased while plasma malondialdehyde (MDA), an indicator for lipid peroxidation was significantly increased in IDDM patients compared to control subjects. Positive correlations between HbA1c and MDA; fasting blood glucose (FBG) and MDA and negative correlations between HbA1c and SOD; MDA and SOD were observed in these patients. No significant correlation existed between HbA1c and fasting blood glucose, GPx or CAT in the diabetic patients. The strong correlations found between lipid peroxidation, antioxidant enzymes and diabetes parameters confirms the existence of oxidative stress in our IDDM patients.

Matched MeSH terms: Lipid Peroxidation*
Antioxidant synergism between ethanolic Centella asiatica extracts and α-tocopherol in model systems

Thoo YY, Abas F, Lai OM, Ho CW, Yin J, Hedegaard RV, et al.

Food Chem, 2013 Jun 1;138(2-3):1215-9.
PMID: 23411234 DOI: 10.1016/j.foodchem.2012.11.013

The synergistic antioxidant effects of ethanolic extracts of Centella asiatica (CE), and α-tocopherol have been studied. The types of interactions exhibited by CE and α-tocopherol combined at different ratios were measured using three assays: 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) radical-scavenging capacity, the β-carotene bleaching system and liposome peroxidation assays. Fixed-fraction isobolographic analysis was used to detect any inducement of the antioxidant activity compared with the individual activities of CE and α-tocopherol. Of all synergistic combinations of CE and α-tocopherol, only fraction 2/3 showed the synergistic combination that fits well in three different assays and can be explained by the regeneration of α-tocopherol by CE despite the interaction effect of β-carotene present in the analytical assay. This phenomenon involved complex interactions between CE and α-tocopherol to exhibit different degrees of interactions that eventually increased antioxidant activity.

Matched MeSH terms: Lipid Peroxidation/drug effects
Atherosclerotic cardiovascular disease: a review of initiators and protective factors

Ellulu MS, Patimah I, Khaza'ai H, Rahmat A, Abed Y, Ali F

Inflammopharmacology, 2016 Feb;24(1):1-10.
PMID: 26750181 DOI: 10.1007/s10787-015-0255-y

Atherosclerotic cardiovascular disease (CVD) is a collective term comprising of a group of disorders of the heart and blood vessels. These diseases are the largest cause of morbidity and premature death worldwide. Coronary heart disease and cerebrovascular disease (stroke) are the most frequently occurring diseases. The two major initiators involved in the development of atherosclerotic CVD are vascular production of reactive oxygen species (ROS) and lipid oxidation. In atherosclerosis development, ROS is associated with rapid loss of anti-inflammatory and anti-atherogenic activities of the endothelium-derived nitric oxide (NO(·)) resulting in endothelial dysfunction. In part involving activation of the transcription factor NF-κB, ROS have been involved in signaling cascades leading to vascular pro-inflammatory and pro-thrombotic gene expression. ROS is also a potent activator of matrix metalloproteinases (MMPs), which indicate plaque destabilization and rupture. The second initiator involved in atherosclerotic CVD is the oxidation of low-density lipoproteins (LDL). Oxidation of LDL in vessel wall leads to an inflammatory cascade that activates atherogenic pathway leading to foam cell formation. The accumulation of foam cells leads to fatty streak formation, which is the earliest visible atherosclerotic lesion. In contrast, the cardiac sarco/endoplasmic reticulum Ca(2+)-ATPase (SERCA2a) and hepatic apolipoprotein E (apoE) expression can improve cardiovascular function. SERCA2a regulates the cardiac contractile function by lowering cytoplasmic calcium levels during relaxation, and affecting NO(·) action in vascular cells, while apoE is a critical ligand in the plasma clearance of triglyceride- and cholesterol-rich lipoproteins.

Matched MeSH terms: Lipid Peroxidation/physiology
Fulltext Antioxidative Effects and Inhibition of Human Low Density Lipoprotein Oxidation In Vitro of Polyphenolic Compounds in Flammulina velutipes (Golden Needle Mushroom)

Rahman MA, Abdullah N, Aminudin N

Oxid Med Cell Longev, 2015;2015:403023.
PMID: 26180589 DOI: 10.1155/2015/403023

Dietary polyphenolic compounds mediate polynomial actions in guarding against multiple diseases. Atherosclerosis is an oxidative stress driven pathophysiological complication where free radical induced oxidative modification of low density lipoprotein (LDL) plays the ground breaking role. Mushrooms have been highly regarded for possessing an antioxidant arsenal. Polyphenolic compounds present in dietary mushrooms seem pertinent in withstanding LDL oxidation en route to controlling atherosclerosis. In this study, the antioxidative effect of five solvent fractions consisting of methanol : dichloromethane (M : DCM), hexane (HEX), dichloromethane (DCM), ethyl acetate (EA), and aqueous residue (AQ) of Flammulina velutipes was evaluated. M : DCM fraction showed the most potent 2,2-diphenyl-1-picrylhydrazyl radical scavenging effect with IC50 of 0.86 mg/mL and total phenolic content of 56.36 gallic acid equivalent/g fraction. In LDL oxidation inhibitory tests, M : DCM fraction at 1 µg/mL concentration mostly lengthened the lag time (125 mins) of conjugated diene formation and inhibited the formation of thiobarbituric acid reactive substances (48.71%, at 1 mg/mL concentration). LC-MS/MS analyses of M : DCM fraction identified the presence of polyphenolic substances protocatechuic acid, p-coumaric, and ellagic acid. These chain-breaking polyphenolics might impart the antioxidative effects of F. velutipes. Thus, mushroom-based dietary polyphenolic compounds might be implicated in slowing down the progression of atherosclerosis.

Matched MeSH terms: Lipid Peroxidation/drug effects*
Effect of alpha-tocopherol on lipid peroxidation and total antioxidant status in spontaneously hypertensive rats

Newaz MA, Nawal NN

Am J Hypertens, 1998 Dec;11(12):1480-5.
PMID: 9880131

The aim of this study was to determine the effects of alpha-tocopherol on lipid peroxidation and total antioxidant status of spontaneously hypertensive rats (SHR), comparing them with normal Wistar-Kyoto (WKY) rats. SHR were divided into three groups and treated with different doses of alpha-tocopherol (alpha1, 17 mg/kg diet; alpha2, 34 mg/kg diet; and alpha3, 170 mg/kg diet). Normal WKY and untreated SHR were used as normal (N) and hypertensive control (HC). Blood pressures were recorded every 10 days for 3 months. At the end of the trial, animals were killed and measurement of plasma total antioxidant status, plasma superoxide dismutase (SOD) activity, and lipid peroxide levels in plasma and blood vessels was carried out following well-established methods. From our study it was found that lipid peroxides in thoracic aorta (N, 0.47 +/- 0.17; H, 0.96 +/- 0.37; P < .0001) and plasma (N, 0.06 +/- 0.01; H, 0.13 +/- 0.01) were significantly higher in hypertensives than in normal rats. SOD activity was significantly lower in hypertensive than normal rats (N, 172.93 +/- 46.91; H, 110.08 +/- 14.38; P < .005). Total antioxidant status was significantly higher in normal than hypertensive rats (N, 0.88 +/- 0.05; H, 0.83 +/- 0.02; P < .05). After the antioxidant trial, it was found that in the treated groups rise of blood pressure was prevented significantly (P < .001) and lipid peroxides in blood vessels were significantly reduced more than in the controls (P < .001). For plasma lipid peroxide it was only significant for groups alpha2 (P < .001) and alpha3 (P < .05). Although all three treated groups showed improved total antioxidant status, only groups alpha2 (0.87 +/- 0.04, P < .005) and alpha3 (1.20 +/- 0.18, P < .001) were statistically significant. All the three groups showed significant increases in their SOD activity (P < .001). Correlation studies showed that total antioxidant status and SOD were significantly negatively correlated with blood pressure in normal rats (P = .007; P = .008). Lipid peroxides in both blood vessel and plasma showed a positive correlation. In the treated groups, lipid peroxides in blood vessels maintained a significant positive correlation with blood pressure in all groups (alpha1, P = .021; alpha2, P = .019; alpha3, P = .002), whereas for plasma lipid peroxides the correlation was in groups alpha1 (P = .005) and alpha2 (P = .009). For SOD activity, significant negative correlations were found with blood pressure in the alpha2 (P = .017) and alpha3 (P = .025) groups. Total antioxidant status maintained a significant negative correlation with blood pressure in all three groups (alpha1, P = .012; alpha2, P = .044; alpha3, P = .014). In conclusion it was found that supplement of alpha-tocopherol may prevent development of increased blood pressure, reduce lipid peroxides in plasma and blood vessels, and enhance the total antioxidant status, including SOD activity.

Matched MeSH terms: Lipid Peroxidation/drug effects*
A comparison of bleeding efficiency, microbiological quality and lipid oxidation in goats subjected to conscious halal slaughter and slaughter following minimal anesthesia

Sabow AB, Sazili AQ, Zulkifli I, Goh YM, Ab Kadir MZ, Abdulla NR, et al.

Meat Sci, 2015 Jun;104:78-84.
PMID: 25732178 DOI: 10.1016/j.meatsci.2015.02.004

The study assessed the effect of conscious halal slaughter and slaughter following minimal anesthesia on bleeding efficiency of goats and keeping quality of goat meat. Ten Boer cross bucks were divided into two groups and subjected to either halal slaughter without stunning (HS) or minimal anesthesia prior to slaughter (AS). The blood lost during exsanguination was measured. Residual blood was further quantified by determination of hemoglobin and myoglobin content in longissimus lumborum muscle. Storage stability of the meat was evaluated by microbiological analysis and lipid oxidation. Blood loss at exsanguination, residual hemoglobin and lipid oxidation were not significantly different (p>0.05) between HS and AS. Lactic acid bacteria was the only microbe that was significantly elevated after 24h of storage at 4°C in the AS group. In conclusion, slaughtering goats under minimal anesthesia or fully conscious did not affect bleeding efficiency and keeping quality of goat meat.

Matched MeSH terms: Lipid Peroxidation*
Antibodies against malondialdehyde (MDA) in MRL/lpr/lpr mice: evidence for an autoimmune mechanism involving lipid peroxidation

Yahya MD, Pinnas JL, Meinke GC, Lung CC

J Autoimmun, 1996 Feb;9(1):3-9.
PMID: 8845052

Previous studies have shown that lipid peroxidative processes may play a role in disease pathogenesis in lupus-prone MRL/lpr mice. Studies were thus performed to determine if an immune response against malondialdehyde (MDA), a highly reactive byproduct of lipid peroxidation, was present in these mice. By using MDA-modified mouse serum albumin (MSA) as antigens in ELISA, we found that these mice produce high levels of MDA-specific antibodies in the complement-fixing IgG2a and IgG2b subclasses. Anti-MDA antibodies were also found in MRL/+ mice but in significantly lower levels. The specificity of these antibodies was verified by inhibition ELISA. MDA may contribute to disease pathogenesis in these mice by altering the immunogenicity of self molecules, eliciting an immune response and forming immune complexes that may deposit in tissues.

Matched MeSH terms: Lipid Peroxidation/immunology*
Lipid peroxidation in the descending thoracic aorta of rats deprived of REM sleep using the inverted flowerpot technique

Nawi A, Eu KL, Faris ANA, Wan Ahmad WAN, Noordin L

Exp Physiol, 2020 08;105(8):1223-1231.
PMID: 32539237 DOI: 10.1113/EP088667

NEW FINDINGS: What is the central question of this study? Deprivation of rapid eye movement (REM) sleep is associated with increased oxidative stress, but its effects on the blood vessels are poorly documented. We investigated whether REM sleep deprivation induces oxidative stress and causes lipid peroxidation in the aorta. What is the main finding and its important? We demonstrate that REM sleep deprivation induces oxidative stress and mediates lipid peroxidation in the aorta. This can cause endothelial changes and increased blood pressure. These findings will contribute to the growing body of literature on the mechanism underlying the effects of sleep deprivation on cardiovascular disease.
ABSTRACT: Oxidative stress-mediated lipid peroxidation is a known cause of endothelial injury or dysfunction. Deprivation of rapid eye movement (REM) sleep is associated with oxidative stress. To date, the pathogenesis of increased blood pressure after sleep deprivation remains poorly understood, particularly in the REM sleep phase. Our aim was to investigate the effects of REM sleep deprivation on blood vessels in the REM sleep-deprived rat model. Twenty-eight male Sprague-Dawley rats were divided into four equal groups: free-moving control rats, rats deprived of REM sleep for 72 h (REMsd), tank control rats and 72 h sleep-recovered rats after 72 h of REM sleep deprivation. The rats were deprived of REM sleep using the inverted flowerpot technique. Food consumption, body weight gain and systolic blood pressure were monitored. At the end of the experiment, the descending thoracic aorta was isolated for the measurement of oxidative stress markers. Despite a significant increase in food consumption in the REMsd group compared with the other groups, there was a significant reduction in body weight gain. Systolic blood pressure also showed a significant increase in the REMsd group compared with the other groups. Superoxide dismutase activity was significantly lower and malondialdehyde concentrations significantly higher in the REMsd group compared with the other groups. Increased levels of malondialdehyde are suggestive of lipid peroxidation in the blood vessels, and oxidative stress may be attributed to the initiation of the process. The changes after REM sleep deprivation revert during sleep recovery. In conclusion, the findings of the present study provide convincing evidence that REM sleep deprivation induced lipid peroxidation, leading to endothelial damage.

Matched MeSH terms: Lipid Peroxidation*
Fulltext Antioxidative Potential of a Streptomyces sp. MUM292 Isolated from Mangrove Soil

Tan LT, Chan KG, Chan CK, Khan TM, Lee LH, Goh BH

Biomed Res Int, 2018;2018:4823126.
PMID: 29805975 DOI: 10.1155/2018/4823126

Mangrove derived microorganisms constitute a rich bioresource for bioprospecting of bioactive natural products. This study explored the antioxidant potentials of Streptomyces bacteria derived from mangrove soil. Based on 16S rRNA phylogenetic analysis, strain MUM292 was identified as the genus Streptomyces. Strain MUM292 showed the highest 16S rRNA gene sequence similarity of 99.54% with S. griseoruber NBRC12873T. Furthermore, strain MUM292 was also characterized and showed phenotypic characteristics consistent with Streptomyces bacteria. Fermentation and extraction were performed to obtain the MUM292 extract containing the secondary metabolites of strain MUM292. The extract displayed promising antioxidant activities, including DPPH, ABTS, and superoxide radical scavenging and also metal-chelating activities. The process of lipid peroxidation in lipid-rich product was also retarded by MUM292 extract and resulted in reduced MDA production. The potential bioactive constituents of MUM292 extract were investigated using GC-MS and preliminary detection showed the presence of pyrazine, pyrrole, cyclic dipeptides, and phenolic compound in MUM292 extract. This work demonstrates that Streptomyces MUM292 can be a potential antioxidant resource for food and pharmaceutical industries.

Matched MeSH terms: Lipid Peroxidation/drug effects

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