Jetty Chung-Yung Lee | The University of Hong Kong (original) (raw)
Papers by Jetty Chung-Yung Lee
Biomolecules
Consumption of omega-3 polyunsaturated fatty acids (n-3 PUFAs) rich fatty fish is known to provid... more Consumption of omega-3 polyunsaturated fatty acids (n-3 PUFAs) rich fatty fish is known to provide an array of health benefits. However, high temperature in food preparation, such as pan-frying, potentially degrades eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) of the n-3 PUFAs by heat oxidation. The addition of antioxidant condiments, and herbs in particular, may retard PUFA peroxidation and preserve EPA and DHA during pan-frying. In this study, different types of antioxidant condiments (sage, rosemary, black peppercorn, thyme, basil, and garlic) were tested for antioxidant capacity, and the condiment with the highest capacity was selected for its effect on lipid oxidation of salmon. The changes in fatty acids and lipid peroxidation of salmon, during pan-frying with the selected condiment (olive oil infused with rosemary, RO(infused)), were compared with salmon prepared in extra virgin olive oil, olive oil, or without oil. The total saturated fatty acid was found to be...
Lactobacillus rhamnosus GG and Oat Beta‐Glucan Regulated Fatty Acid Profiles along the Gut‐Liver‐Brain Axis of Mice Fed with High Fat Diet and Demonstrated Antioxidant and Anti‐Inflammatory Potentials
Molecular Nutrition & Food Research
Dietary Oat Bran Increases Some Proinflammatory Polyunsaturated Fatty-Acid Oxidation Products and Reduces Anti-Inflammatory Products in Apolipoprotein E−/− Mice
Lipids
Moving forward with isoprostanes, neuroprostanes and phytoprostanes: where are we now?
Essays in Biochemistry
Polyunsaturated fatty acids (PUFAs) are essential components in eukaryotic cell membrane. They ta... more Polyunsaturated fatty acids (PUFAs) are essential components in eukaryotic cell membrane. They take part in the regulation of cell signalling pathways and act as precursors in inflammatory metabolism. Beside these, PUFAs auto-oxidize through free radical initiated mechanism and release key products that have various physiological functions. These products surfaced in the early nineties and were classified as prostaglandin isomers or isoprostanes, neuroprostanes and phytoprostanes. Although these molecules are considered robust biomarkers of oxidative damage in diseases, they also contain biological activities in humans. Conceptual progress in the last 3 years has added more understanding about the importance of these molecules in different fields. In this chapter, a brief overview of the past 30 years and the recent scope of these molecules, including their biological activities, biosynthetic pathways and analytical approaches are discussed.
Nonenzymatic oxygenated metabolite of docosahexaenoic acid, 4( RS )‐4‐F 4t ‐neuroprostane, acts as a bioactive lipid molecule in neuronal cells
FEBS Letters
Dietary Fiber from Oat and Rye Brans Ameliorate Western Diet–Induced Body Weight Gain and Hepatic Inflammation by the Modulation of Short‐Chain Fatty Acids, Bile Acids, and Tryptophan Metabolism
Molecular Nutrition & Food Research
Oxidative Medicine and Cellular Longevity
Almost 50% of infertility cases are associated with human male infertility. The sperm membrane is... more Almost 50% of infertility cases are associated with human male infertility. The sperm membrane is a key structure influencing sperm morphology and function in normal and pathological conditions. The fatty acid profile determines the performance not only of sperm motility but also of acrosomal reaction and sperm-oocyte fusion. This review presents available knowledge on the role of fatty acid composition in human sperm and spermatogenesis and discusses the influence of dietary fatty acids on the sperm fatty acid profile. Recent studies in biological sciences and clinical researches in this field are also reported. The topic object of this review has potential application in medicine by identifying potential causes of infertility.
Nanosized silver, but not titanium dioxide or zinc oxide, enhances oxidative stress and inflammatory response by inducing 5-HETE activation in THP-1 cells
Nanotoxicology
Molecular Aspects of Medicine
ω3 Polyunsaturated fatty acids (ω3 PUFAs) have several biological properties including anti-arrhy... more ω3 Polyunsaturated fatty acids (ω3 PUFAs) have several biological properties including anti-arrhythmic effects. However, there are some evidences that it is not solely ω3 PUFAs per se that are biologically active but the nonenzymatic oxygenated metabolites of polyunsaturated fatty acids (NEO-PUFAs) like isoprostanes and neuroprostanes. Recent question arises how these molecules take part in physiological homeostasis, show biological bioactivities and anti-inflammatory properties. Furthermore, they are involved in the circulations of childbirth, by inducing the closure of the ductus arteriosus. In addition, oxidative stress which can be beneficial for the heart in given environmental conditions such as the presence of ω3 PUFAs on the site of the stress and the signaling pathways involved are also explained in this review.
Increase in omega-6 and decrease in omega-3 polyunsaturated fatty acid oxidation elevates the risk of exudative AMD development in adults with Chinese diet
Free Radical Biology and Medicine
Nanotoxicology
Nano-sized metal oxides are currently the most manufactured nanomaterials (NMs), and are increasi... more Nano-sized metal oxides are currently the most manufactured nanomaterials (NMs), and are increasingly used in consumer products. Recent exposure data reveal a genuine potential for adverse health outcomes for a vast array of NMs, however the underlying mechanisms are not fully understood. To elucidate size-related molecular effects, differentiated THP-1 cells were exposed to nano-sized materials (n-TiO2, n-ZnO, nAg), or their bulk-sized (b-ZnO, b-TiO2) or ionic (i-Ag) counterparts, and genome-wide gene expression changes were studied at low-toxic concentrations (<15% cytotoxicity). TiO2 materials were non-toxic in MTT assay, inducing only minor transcriptional changes. ZnO and Ag elicited dose-dependent cytotoxicity, wherein ionic and particulate effects were synergistic with respect to n-ZnO-induced cytotoxicity. In gene expression analyses, 6h and 24h samples formed two separate hierarchical clusters. N-ZnO and nAg shared only 3.1 % and 24.6 % differentially expressed genes (DEGs) when compared to corresponding control. All particles, except TiO2, activated various metallothioneins. At 6h, n-Zn, b-Zn and nAg induced various immunity related genes associating to pattern recognition (including toll-like receptor), macrophage maturation, inflammatory response (TNF, IL-1beta), chemotaxis (CXCL8) and leucocyte migration (CXCL2-3, CXCL14). After 24h exposure, especially nAg induced the expression of genes related to virus recognition and type I interferon responses. These results strongly suggest that in addition to ionic effects mediated by metallothioneins, n-Zn and nAg induce expression of genes involved in several innate and adaptive immunity associated pathways, which are known to play crucial role in immuno-regulation. This raises the concern of safe use of metal oxide and metal nanoparticle products, and their biological effects.
Relevance of 4-F4t-neuroprostane and 10-F4t-neuroprostane to neurological diseases
Free radical biology & medicine, Jan 9, 2017
F4-neuroprostanes (F4-NeuroPs) are non-enzymatic oxidized products derived from docosahexaenoic a... more F4-neuroprostanes (F4-NeuroPs) are non-enzymatic oxidized products derived from docosahexaenoic acid (DHA) and are suggested to be oxidative damage biomarkers of neurological diseases. However, 128 isomers can be formed from DHA oxidation and among them, 4(RS)-4-F4t-NeuroP (4-F4t-NeuroP) and 10(RS)-10-F4t-NeuroP (10-F4t-NeuroP) are the most studied. Here, we report the identification and the clinical relevance of 4-F4t-NeuroP and 10-F4t-NeuroP in plasma of four different neurological diseases, including multiple sclerosis (MS), autism spectrum disorders (ASD), Rett syndrome (RTT), and Down syndrome (DS). The identification and the optimization of the method were carried out by gas chromatography/negative-ion chemical ionization tandem mass spectrometry (GC/NICI-MS/MS) using chemically synthesized 4-F4t-NeuroP and 10-F4t-NeuroP standards and in oxidized DHA liposome. Both 4-F4t-NeuroP and 10-F4t-NeuroP were detectable in all plasma samples from MS (n = 16), DS (n = 16), ASD (n = 9) a...
Insight into the contribution of isoprostanoids to the health effects of omega 3 PUFAs
Prostaglandins & Other Lipid Mediators
Omega 3 polyunsaturated fatty acids have been reported to confer beneficial health effects notabl... more Omega 3 polyunsaturated fatty acids have been reported to confer beneficial health effects notably in the field of cardiovascular and inflammatory diseases. The current knowledge suggests a significant portion of the effects of omega 3 polyunsaturated fatty acids are mediated by their oxygenated metabolites. This review attempts to cover the current literature about the contribution of specific omega 3 oxygenated metabolites, namely omega 3 isoprostanoids, which are produced through free-radical mediated oxidation. A special emphasis has been given to the most biologically relevant omega 3 polyunsaturated fatty acids namely the α-linolenic, eicosapentaenoic and docosahexaenoic acids. The review includes a comprehensive description of the biosynthetic pathways, a summary of studies related to the biological significance of omega 3 isoprostanoids as well as a critical description of analytical development in the field of omega 3 isoprostanoids profiling in biological samples.
Oxidative Damage In Ischemic Stroke. A Biomarker Study
Stroke
Isoprostanes, neuroprostanes and phytoprostanes. An overview of 25 years of research in chemistry and biology
Progress in Lipid Research
Since the beginning of the 1990's diverse types of metabolites originating from polyunsat... more Since the beginning of the 1990's diverse types of metabolites originating from polyunsaturated fatty acids, formed under autooxidative conditions were discovered. Known as prostaglandin isomers (or isoprostanoids) originating from arachidonic acid, neuroprostanes from docosahexaenoic acid, and phytoprostanes from α-linolenic acid proved to be prevalent in biology. The syntheses of these compounds by organic chemists and the development of sophisticated mass spectrometry methods has boosted our understanding of the isoprostanoid biology. In recent years, it has become accepted that these molecules not only serve as markers of oxidative damage but also exhibit a wide range of bioactivities. In addition, isoprostanoids have emerged as indicators of oxidative stress in humans and their environment. This review explores in detail the isoprostanoid chemistry and biology that has been achieved in the past three decades.
Short-time UVA exposure to human keratinocytes instigated polyunsaturated fatty acid without inducing lipid peroxidation
Free radical research, Jan 17, 2017
Short-term exposure to ultraviolet A (UVA) radiation can directly injure our skin through inflamm... more Short-term exposure to ultraviolet A (UVA) radiation can directly injure our skin through inflammatory response and indirectly through oxidative stress, triggering polyunsaturated fatty acid (PUFA) peroxidation in skin cell membrane and formation of DNA adduct, 8-hydroxy-2'-deoxyguanosine (8-OHdG). It is known that UVA exposure leads to photoaging, immunosuppression and skin cancer. However, the changes in PUFA and its oxidized metabolites, and cell cycle after short UVA exposure, are debatable. In this study, human keratinocytes (HaCaT) were exposed to low dose (5 J/cm(2)) and high dose (20 J/cm(2)) of UVA and assessed immediately, 8 h, 12 h, and 24 h post-treatment. Both doses showed a transient suppression in S-phase after 8 h of UVA exposure, and G2/M phase arrest after 12-h UVA exposure in the cell cycle but subsequently returned to normal cycle. Also, no observable DNA damage took place, where 8-OHdG levels were below par after 24-h UVA exposure. A dose of 20 J/cm(2) UVA s...
Two sides of the same coin: NEO-PUFAs in Rett syndrome and post-infarction cardiac arrhythmias
European Journal of Lipid Science and Technology, 2017
Non-enzymatic oxidized metabolite of DHA, 4(RS)-4-F4t-neuroprostane protects the heart against reperfusion injury
Free radical biology & medicine, 2017
Acute myocardial infarction leads to an increase in oxidative stress and lipid peroxidation. 4(RS... more Acute myocardial infarction leads to an increase in oxidative stress and lipid peroxidation. 4(RS)-4-F4t-Neuroprostane (4-F4t-NeuroP) is a mediator produced by non-enzymatic free radical peroxidation of the cardioprotective polyunsaturated fatty acid, docosahexaenoic acid (DHA). In this study, we investigated whether intra-cardiac delivery of 4-F4t-NeuroP (0.03mg/kg) prior to occlusion (ischemia) prevents and protects rat myocardium from reperfusion damages. Using a rat model of ischemic-reperfusion (I/R), we showed that intra-cardiac infusion of 4-F4t-NeuroP significantly decreased infarct size following reperfusion (-27%) and also reduced ventricular arrhythmia score considerably during reperfusion (-41%). Most notably, 4-F4t-NeuroP decreased ventricular tachycardia and post-reperfusion lengthening of QT interval. The evaluation of the mitochondrial homeostasis indicates a limitation of mitochondrial swelling in response to Ca(2+) by decreasing the mitochondrial permeability trans...
The novelty of phytofurans, isofurans, dihomo-isofurans and neurofurans: Discovery, synthesis and potential application
Biochimie, 2016
Polyunsaturated fatty acids (PUFA) are oxidized in vivo under oxidative stress through free radic... more Polyunsaturated fatty acids (PUFA) are oxidized in vivo under oxidative stress through free radical pathway and release cyclic oxygenated metabolites, which are commonly classified as isoprostanes and isofurans. The discovery of isoprostanes goes back twenty-five years compared to fifteen years for isofurans, and great many are discovered. The biosynthesis, the nomenclature, the chemical synthesis of furanoids from α-linolenic acid (ALA, C18:3 n-3), arachidonic acid (AA, C20:4 n-6), adrenic acid (AdA, 22:4 n-6) and docosahexaenoic acid (DHA, 22:6 n-3) as well as their identification and implication in biological systems are highlighted in this review.
Extra Virgin Olive Oil Reduced Polyunsaturated Fatty Acid and Cholesterol Oxidation in Rodent Liver: Is This Accounted for Hydroxytyrosol-Fatty Acid Conjugation?
Chemical Research in Toxicology, 2016
The effects of extra virgin olive oil (EVOO) and carbon tetrachloride (CCl4) induced oxidative st... more The effects of extra virgin olive oil (EVOO) and carbon tetrachloride (CCl4) induced oxidative stress in rats were determined by the generation of isoprostanoids. These are known to be robust biomarkers to evaluate nonenzymatic and free radical related oxidation. Other oxidative stress biomarkers such as hydroxyeicosatetraenoic acid products (HETEs) and cholesterol oxidation products (COPs) were also determined. The rodents received a control diet, high-fat diet (20% w/w) composed of extra virgin olive oil (EVOO), corn oil (CO), or lard, and high-fat diets with CCl4 insult throughout the experimental period. The EVOO diet was found to suppress the formation of isoprostanoids and COPs compared to that of the control. EVOO also had a high total phenolic content and antioxidant activity compared to those of CO and lard and may be contributed to by the hydroxytyrosol component conjugated to fatty acids (HT-FA). This is the first study to identify HT-FA in EVOO, and it was 4-fold higher than that of olive oil, whereas none was found in corn oil. Furthermore, the EVOO diet showed reduced liver lipid vesicles in CCl4 treated rats compared to that of the control. However, liver toxicity measurements of AST (aspartate transaminase) and ALT (alanine transaminase) activities showed augmentation with CCl4 treatment but were not alleviated by the diets given. Our findings suggest that EVOO is a daily functional food capable of enhancing the antioxidant system for liver protection; the effect is potentially attributed to the phenolic and lipophenolic (phenol conjugated by fatty acids) content.
Biomolecules
Consumption of omega-3 polyunsaturated fatty acids (n-3 PUFAs) rich fatty fish is known to provid... more Consumption of omega-3 polyunsaturated fatty acids (n-3 PUFAs) rich fatty fish is known to provide an array of health benefits. However, high temperature in food preparation, such as pan-frying, potentially degrades eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) of the n-3 PUFAs by heat oxidation. The addition of antioxidant condiments, and herbs in particular, may retard PUFA peroxidation and preserve EPA and DHA during pan-frying. In this study, different types of antioxidant condiments (sage, rosemary, black peppercorn, thyme, basil, and garlic) were tested for antioxidant capacity, and the condiment with the highest capacity was selected for its effect on lipid oxidation of salmon. The changes in fatty acids and lipid peroxidation of salmon, during pan-frying with the selected condiment (olive oil infused with rosemary, RO(infused)), were compared with salmon prepared in extra virgin olive oil, olive oil, or without oil. The total saturated fatty acid was found to be...
Lactobacillus rhamnosus GG and Oat Beta‐Glucan Regulated Fatty Acid Profiles along the Gut‐Liver‐Brain Axis of Mice Fed with High Fat Diet and Demonstrated Antioxidant and Anti‐Inflammatory Potentials
Molecular Nutrition & Food Research
Dietary Oat Bran Increases Some Proinflammatory Polyunsaturated Fatty-Acid Oxidation Products and Reduces Anti-Inflammatory Products in Apolipoprotein E−/− Mice
Lipids
Moving forward with isoprostanes, neuroprostanes and phytoprostanes: where are we now?
Essays in Biochemistry
Polyunsaturated fatty acids (PUFAs) are essential components in eukaryotic cell membrane. They ta... more Polyunsaturated fatty acids (PUFAs) are essential components in eukaryotic cell membrane. They take part in the regulation of cell signalling pathways and act as precursors in inflammatory metabolism. Beside these, PUFAs auto-oxidize through free radical initiated mechanism and release key products that have various physiological functions. These products surfaced in the early nineties and were classified as prostaglandin isomers or isoprostanes, neuroprostanes and phytoprostanes. Although these molecules are considered robust biomarkers of oxidative damage in diseases, they also contain biological activities in humans. Conceptual progress in the last 3 years has added more understanding about the importance of these molecules in different fields. In this chapter, a brief overview of the past 30 years and the recent scope of these molecules, including their biological activities, biosynthetic pathways and analytical approaches are discussed.
Nonenzymatic oxygenated metabolite of docosahexaenoic acid, 4( RS )‐4‐F 4t ‐neuroprostane, acts as a bioactive lipid molecule in neuronal cells
FEBS Letters
Dietary Fiber from Oat and Rye Brans Ameliorate Western Diet–Induced Body Weight Gain and Hepatic Inflammation by the Modulation of Short‐Chain Fatty Acids, Bile Acids, and Tryptophan Metabolism
Molecular Nutrition & Food Research
Oxidative Medicine and Cellular Longevity
Almost 50% of infertility cases are associated with human male infertility. The sperm membrane is... more Almost 50% of infertility cases are associated with human male infertility. The sperm membrane is a key structure influencing sperm morphology and function in normal and pathological conditions. The fatty acid profile determines the performance not only of sperm motility but also of acrosomal reaction and sperm-oocyte fusion. This review presents available knowledge on the role of fatty acid composition in human sperm and spermatogenesis and discusses the influence of dietary fatty acids on the sperm fatty acid profile. Recent studies in biological sciences and clinical researches in this field are also reported. The topic object of this review has potential application in medicine by identifying potential causes of infertility.
Nanosized silver, but not titanium dioxide or zinc oxide, enhances oxidative stress and inflammatory response by inducing 5-HETE activation in THP-1 cells
Nanotoxicology
Molecular Aspects of Medicine
ω3 Polyunsaturated fatty acids (ω3 PUFAs) have several biological properties including anti-arrhy... more ω3 Polyunsaturated fatty acids (ω3 PUFAs) have several biological properties including anti-arrhythmic effects. However, there are some evidences that it is not solely ω3 PUFAs per se that are biologically active but the nonenzymatic oxygenated metabolites of polyunsaturated fatty acids (NEO-PUFAs) like isoprostanes and neuroprostanes. Recent question arises how these molecules take part in physiological homeostasis, show biological bioactivities and anti-inflammatory properties. Furthermore, they are involved in the circulations of childbirth, by inducing the closure of the ductus arteriosus. In addition, oxidative stress which can be beneficial for the heart in given environmental conditions such as the presence of ω3 PUFAs on the site of the stress and the signaling pathways involved are also explained in this review.
Increase in omega-6 and decrease in omega-3 polyunsaturated fatty acid oxidation elevates the risk of exudative AMD development in adults with Chinese diet
Free Radical Biology and Medicine
Nanotoxicology
Nano-sized metal oxides are currently the most manufactured nanomaterials (NMs), and are increasi... more Nano-sized metal oxides are currently the most manufactured nanomaterials (NMs), and are increasingly used in consumer products. Recent exposure data reveal a genuine potential for adverse health outcomes for a vast array of NMs, however the underlying mechanisms are not fully understood. To elucidate size-related molecular effects, differentiated THP-1 cells were exposed to nano-sized materials (n-TiO2, n-ZnO, nAg), or their bulk-sized (b-ZnO, b-TiO2) or ionic (i-Ag) counterparts, and genome-wide gene expression changes were studied at low-toxic concentrations (<15% cytotoxicity). TiO2 materials were non-toxic in MTT assay, inducing only minor transcriptional changes. ZnO and Ag elicited dose-dependent cytotoxicity, wherein ionic and particulate effects were synergistic with respect to n-ZnO-induced cytotoxicity. In gene expression analyses, 6h and 24h samples formed two separate hierarchical clusters. N-ZnO and nAg shared only 3.1 % and 24.6 % differentially expressed genes (DEGs) when compared to corresponding control. All particles, except TiO2, activated various metallothioneins. At 6h, n-Zn, b-Zn and nAg induced various immunity related genes associating to pattern recognition (including toll-like receptor), macrophage maturation, inflammatory response (TNF, IL-1beta), chemotaxis (CXCL8) and leucocyte migration (CXCL2-3, CXCL14). After 24h exposure, especially nAg induced the expression of genes related to virus recognition and type I interferon responses. These results strongly suggest that in addition to ionic effects mediated by metallothioneins, n-Zn and nAg induce expression of genes involved in several innate and adaptive immunity associated pathways, which are known to play crucial role in immuno-regulation. This raises the concern of safe use of metal oxide and metal nanoparticle products, and their biological effects.
Relevance of 4-F4t-neuroprostane and 10-F4t-neuroprostane to neurological diseases
Free radical biology & medicine, Jan 9, 2017
F4-neuroprostanes (F4-NeuroPs) are non-enzymatic oxidized products derived from docosahexaenoic a... more F4-neuroprostanes (F4-NeuroPs) are non-enzymatic oxidized products derived from docosahexaenoic acid (DHA) and are suggested to be oxidative damage biomarkers of neurological diseases. However, 128 isomers can be formed from DHA oxidation and among them, 4(RS)-4-F4t-NeuroP (4-F4t-NeuroP) and 10(RS)-10-F4t-NeuroP (10-F4t-NeuroP) are the most studied. Here, we report the identification and the clinical relevance of 4-F4t-NeuroP and 10-F4t-NeuroP in plasma of four different neurological diseases, including multiple sclerosis (MS), autism spectrum disorders (ASD), Rett syndrome (RTT), and Down syndrome (DS). The identification and the optimization of the method were carried out by gas chromatography/negative-ion chemical ionization tandem mass spectrometry (GC/NICI-MS/MS) using chemically synthesized 4-F4t-NeuroP and 10-F4t-NeuroP standards and in oxidized DHA liposome. Both 4-F4t-NeuroP and 10-F4t-NeuroP were detectable in all plasma samples from MS (n = 16), DS (n = 16), ASD (n = 9) a...
Insight into the contribution of isoprostanoids to the health effects of omega 3 PUFAs
Prostaglandins & Other Lipid Mediators
Omega 3 polyunsaturated fatty acids have been reported to confer beneficial health effects notabl... more Omega 3 polyunsaturated fatty acids have been reported to confer beneficial health effects notably in the field of cardiovascular and inflammatory diseases. The current knowledge suggests a significant portion of the effects of omega 3 polyunsaturated fatty acids are mediated by their oxygenated metabolites. This review attempts to cover the current literature about the contribution of specific omega 3 oxygenated metabolites, namely omega 3 isoprostanoids, which are produced through free-radical mediated oxidation. A special emphasis has been given to the most biologically relevant omega 3 polyunsaturated fatty acids namely the α-linolenic, eicosapentaenoic and docosahexaenoic acids. The review includes a comprehensive description of the biosynthetic pathways, a summary of studies related to the biological significance of omega 3 isoprostanoids as well as a critical description of analytical development in the field of omega 3 isoprostanoids profiling in biological samples.
Oxidative Damage In Ischemic Stroke. A Biomarker Study
Stroke
Isoprostanes, neuroprostanes and phytoprostanes. An overview of 25 years of research in chemistry and biology
Progress in Lipid Research
Since the beginning of the 1990's diverse types of metabolites originating from polyunsat... more Since the beginning of the 1990's diverse types of metabolites originating from polyunsaturated fatty acids, formed under autooxidative conditions were discovered. Known as prostaglandin isomers (or isoprostanoids) originating from arachidonic acid, neuroprostanes from docosahexaenoic acid, and phytoprostanes from α-linolenic acid proved to be prevalent in biology. The syntheses of these compounds by organic chemists and the development of sophisticated mass spectrometry methods has boosted our understanding of the isoprostanoid biology. In recent years, it has become accepted that these molecules not only serve as markers of oxidative damage but also exhibit a wide range of bioactivities. In addition, isoprostanoids have emerged as indicators of oxidative stress in humans and their environment. This review explores in detail the isoprostanoid chemistry and biology that has been achieved in the past three decades.
Short-time UVA exposure to human keratinocytes instigated polyunsaturated fatty acid without inducing lipid peroxidation
Free radical research, Jan 17, 2017
Short-term exposure to ultraviolet A (UVA) radiation can directly injure our skin through inflamm... more Short-term exposure to ultraviolet A (UVA) radiation can directly injure our skin through inflammatory response and indirectly through oxidative stress, triggering polyunsaturated fatty acid (PUFA) peroxidation in skin cell membrane and formation of DNA adduct, 8-hydroxy-2'-deoxyguanosine (8-OHdG). It is known that UVA exposure leads to photoaging, immunosuppression and skin cancer. However, the changes in PUFA and its oxidized metabolites, and cell cycle after short UVA exposure, are debatable. In this study, human keratinocytes (HaCaT) were exposed to low dose (5 J/cm(2)) and high dose (20 J/cm(2)) of UVA and assessed immediately, 8 h, 12 h, and 24 h post-treatment. Both doses showed a transient suppression in S-phase after 8 h of UVA exposure, and G2/M phase arrest after 12-h UVA exposure in the cell cycle but subsequently returned to normal cycle. Also, no observable DNA damage took place, where 8-OHdG levels were below par after 24-h UVA exposure. A dose of 20 J/cm(2) UVA s...
Two sides of the same coin: NEO-PUFAs in Rett syndrome and post-infarction cardiac arrhythmias
European Journal of Lipid Science and Technology, 2017
Non-enzymatic oxidized metabolite of DHA, 4(RS)-4-F4t-neuroprostane protects the heart against reperfusion injury
Free radical biology & medicine, 2017
Acute myocardial infarction leads to an increase in oxidative stress and lipid peroxidation. 4(RS... more Acute myocardial infarction leads to an increase in oxidative stress and lipid peroxidation. 4(RS)-4-F4t-Neuroprostane (4-F4t-NeuroP) is a mediator produced by non-enzymatic free radical peroxidation of the cardioprotective polyunsaturated fatty acid, docosahexaenoic acid (DHA). In this study, we investigated whether intra-cardiac delivery of 4-F4t-NeuroP (0.03mg/kg) prior to occlusion (ischemia) prevents and protects rat myocardium from reperfusion damages. Using a rat model of ischemic-reperfusion (I/R), we showed that intra-cardiac infusion of 4-F4t-NeuroP significantly decreased infarct size following reperfusion (-27%) and also reduced ventricular arrhythmia score considerably during reperfusion (-41%). Most notably, 4-F4t-NeuroP decreased ventricular tachycardia and post-reperfusion lengthening of QT interval. The evaluation of the mitochondrial homeostasis indicates a limitation of mitochondrial swelling in response to Ca(2+) by decreasing the mitochondrial permeability trans...
The novelty of phytofurans, isofurans, dihomo-isofurans and neurofurans: Discovery, synthesis and potential application
Biochimie, 2016
Polyunsaturated fatty acids (PUFA) are oxidized in vivo under oxidative stress through free radic... more Polyunsaturated fatty acids (PUFA) are oxidized in vivo under oxidative stress through free radical pathway and release cyclic oxygenated metabolites, which are commonly classified as isoprostanes and isofurans. The discovery of isoprostanes goes back twenty-five years compared to fifteen years for isofurans, and great many are discovered. The biosynthesis, the nomenclature, the chemical synthesis of furanoids from α-linolenic acid (ALA, C18:3 n-3), arachidonic acid (AA, C20:4 n-6), adrenic acid (AdA, 22:4 n-6) and docosahexaenoic acid (DHA, 22:6 n-3) as well as their identification and implication in biological systems are highlighted in this review.
Extra Virgin Olive Oil Reduced Polyunsaturated Fatty Acid and Cholesterol Oxidation in Rodent Liver: Is This Accounted for Hydroxytyrosol-Fatty Acid Conjugation?
Chemical Research in Toxicology, 2016
The effects of extra virgin olive oil (EVOO) and carbon tetrachloride (CCl4) induced oxidative st... more The effects of extra virgin olive oil (EVOO) and carbon tetrachloride (CCl4) induced oxidative stress in rats were determined by the generation of isoprostanoids. These are known to be robust biomarkers to evaluate nonenzymatic and free radical related oxidation. Other oxidative stress biomarkers such as hydroxyeicosatetraenoic acid products (HETEs) and cholesterol oxidation products (COPs) were also determined. The rodents received a control diet, high-fat diet (20% w/w) composed of extra virgin olive oil (EVOO), corn oil (CO), or lard, and high-fat diets with CCl4 insult throughout the experimental period. The EVOO diet was found to suppress the formation of isoprostanoids and COPs compared to that of the control. EVOO also had a high total phenolic content and antioxidant activity compared to those of CO and lard and may be contributed to by the hydroxytyrosol component conjugated to fatty acids (HT-FA). This is the first study to identify HT-FA in EVOO, and it was 4-fold higher than that of olive oil, whereas none was found in corn oil. Furthermore, the EVOO diet showed reduced liver lipid vesicles in CCl4 treated rats compared to that of the control. However, liver toxicity measurements of AST (aspartate transaminase) and ALT (alanine transaminase) activities showed augmentation with CCl4 treatment but were not alleviated by the diets given. Our findings suggest that EVOO is a daily functional food capable of enhancing the antioxidant system for liver protection; the effect is potentially attributed to the phenolic and lipophenolic (phenol conjugated by fatty acids) content.