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Tomohito Hamazaki - One of the best experts on this subject based on the ideXlab platform.
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what are the physiological roles of mead Acid 5 8 11 Eicosatrienoic Acid
2016Co-Authors: Tomohito Hamazaki, Kei HamazakiAbstract:Abstract In this chapter we explore the physiological effects of Mead Acid (5,8,11-Eicosatrienoic Acid, MA) on osteoblasts and osteoclasts in Part 1 and then on angiogenesis in Part 2. Part 1: MA (5,8,11-Eicosatrienoic Acid) is actively synthesized only in the essential fatty Acid (EFA)-deficient state, and until recently the roles of MA in the normal state had not been investigated. Concentrations of MA have long been known to be high in the cartilage of chicken and human infants, even without EFA deficiency. Based on these facts, we postulated that MA prevents the calcification of cartilage. To investigate this possibility, we treated goldfish scales, which served as a source of both osteoblasts and osteoclasts, with MA or oleic Acid for 6 and 18 h at 15 °C. Osteoblastic and osteoclastic activities in the scales were assessed by measuring alkaline phosphatase (ALP) and tartrate-resistant Acid phosphatase activities, respectively. Osteoblastic activity was also evaluated in MC3T3-E1 cells (a murine osteoblast cell line) by incubating cells with MA or oleic Acid for 6 and 18 h at 37 °C and then measuring ALP activity in cell lysate. In the scales, MA (1–102 μmol/L) significantly suppressed ALP after 6 and 18 h of incubation, whereas oleic Acid had no effect on ALP activity. Osteoclastic activity was not affected by either MA or oleic Acid. In the MC3T3-E1 cell line, osteoblastic activity was also significantly decreased by treatment with MA (3–30 μmol/L) for 6 h but not for 18 h. Part 2: Cartilage contains no blood vessels, a condition that likely leads to local EFA deficiency and the synthesis of MA. Why is cartilage an avascular tissue? Is the avascular state supported by MA? If MA inhibits angiogenesis in cartilage, this fatty Acid might support its own synthesis in avascular tissues, namely, MA→avascularity→EFA deficiency→MA synthesis. To examine this possibility, angiogenesis was measured in a coculture system consisting of human umbilical vein endothelial cells and diploid fibroblasts with exogenously added vascular endothelial growth factor-A (VEGF-A, 10 ng/mL) and fatty Acids (0.1–10 μmol/L). Vessel areas were calculated using image analysis software. Treatment with MA was found to dose-dependently inhibit VEGF-A-stimulated angiogenesis after 10 days of incubation. We speculate that the presence of MA in cartilage is related to its vessel-free status, which is associated with local EFA deficiency that in turn leads to the stimulation of MA synthesis. The presence of MA in cartilage may also be important for the prevention of calcification. These mechanisms may also occur in other avascular tissues, such as the cornea and lens.
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Chapter 17 – What Are the Physiological Roles of Mead Acid (5,8,11-Eicosatrienoic Acid)?*
Handbook of Lipids in Human Function, 2016Co-Authors: Tomohito Hamazaki, Kei HamazakiAbstract:In this chapter we explore the physiological effects of Mead Acid (5,8,11-Eicosatrienoic Acid, MA) on osteoblasts and osteoclasts in Part 1 and then on angiogenesis in Part 2. Part 1: MA (5,8,11-Eicosatrienoic Acid) is actively synthesized only in the essential fatty Acid (EFA)-deficient state, and until recently the roles of MA in the normal state had not been investigated. Concentrations of MA have long been known to be high in the cartilage of chicken and human infants, even without EFA deficiency. Based on these facts, we postulated that MA prevents the calcification of cartilage. To investigate this possibility, we treated goldfish scales, which served as a source of both osteoblasts and osteoclasts, with MA or oleic Acid for 6 and 18 h at 15 °C. Osteoblastic and osteoclastic activities in the scales were assessed by measuring alkaline phosphatase (ALP) and tartrate-resistant Acid phosphatase activities, respectively. Osteoblastic activity was also evaluated in MC3T3-E1 cells (a murine osteoblast cell line) by incubating cells with MA or oleic Acid for 6 and 18 h at 37 °C and then measuring ALP activity in cell lysate. In the scales, MA (1–102 μmol/L) significantly suppressed ALP after 6 and 18 h of incubation, whereas oleic Acid had no effect on ALP activity. Osteoclastic activity was not affected by either MA or oleic Acid. In the MC3T3-E1 cell line, osteoblastic activity was also significantly decreased by treatment with MA (3–30 μmol/L) for 6 h but not for 18 h. Part 2: Cartilage contains no blood vessels, a condition that likely leads to local EFA deficiency and the synthesis of MA. Why is cartilage an avascular tissue? Is the avascular state supported by MA? If MA inhibits angiogenesis in cartilage, this fatty Acid might support its own synthesis in avascular tissues, namely, MA→avascularity→EFA deficiency→MA synthesis. To examine this possibility, angiogenesis was measured in a coculture system consisting of human umbilical vein endothelial cells and diploid fibroblasts with exogenously added vascular endothelial growth factor-A (VEGF-A, 10 ng/mL) and fatty Acids (0.1–10 μmol/L). Vessel areas were calculated using image analysis software. Treatment with MA was found to dose-dependently inhibit VEGF-A-stimulated angiogenesis after 10 days of incubation. We speculate that the presence of MA in cartilage is related to its vessel-free status, which is associated with local EFA deficiency that in turn leads to the stimulation of MA synthesis. The presence of MA in cartilage may also be important for the prevention of calcification. These mechanisms may also occur in other avascular tissues, such as the cornea and lens.
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chapter 17 what are the physiological roles of mead Acid 5 8 11 Eicosatrienoic Acid
Handbook of Lipids in Human Function#R##N#Fatty Acids, 2016Co-Authors: Tomohito Hamazaki, Kei HamazakiAbstract:In this chapter we explore the physiological effects of Mead Acid (5,8,11-Eicosatrienoic Acid, MA) on osteoblasts and osteoclasts in Part 1 and then on angiogenesis in Part 2. Part 1: MA (5,8,11-Eicosatrienoic Acid) is actively synthesized only in the essential fatty Acid (EFA)-deficient state, and until recently the roles of MA in the normal state had not been investigated. Concentrations of MA have long been known to be high in the cartilage of chicken and human infants, even without EFA deficiency. Based on these facts, we postulated that MA prevents the calcification of cartilage. To investigate this possibility, we treated goldfish scales, which served as a source of both osteoblasts and osteoclasts, with MA or oleic Acid for 6 and 18 h at 15 °C. Osteoblastic and osteoclastic activities in the scales were assessed by measuring alkaline phosphatase (ALP) and tartrate-resistant Acid phosphatase activities, respectively. Osteoblastic activity was also evaluated in MC3T3-E1 cells (a murine osteoblast cell line) by incubating cells with MA or oleic Acid for 6 and 18 h at 37 °C and then measuring ALP activity in cell lysate. In the scales, MA (1–102 μmol/L) significantly suppressed ALP after 6 and 18 h of incubation, whereas oleic Acid had no effect on ALP activity. Osteoclastic activity was not affected by either MA or oleic Acid. In the MC3T3-E1 cell line, osteoblastic activity was also significantly decreased by treatment with MA (3–30 μmol/L) for 6 h but not for 18 h. Part 2: Cartilage contains no blood vessels, a condition that likely leads to local EFA deficiency and the synthesis of MA. Why is cartilage an avascular tissue? Is the avascular state supported by MA? If MA inhibits angiogenesis in cartilage, this fatty Acid might support its own synthesis in avascular tissues, namely, MA→avascularity→EFA deficiency→MA synthesis. To examine this possibility, angiogenesis was measured in a coculture system consisting of human umbilical vein endothelial cells and diploid fibroblasts with exogenously added vascular endothelial growth factor-A (VEGF-A, 10 ng/mL) and fatty Acids (0.1–10 μmol/L). Vessel areas were calculated using image analysis software. Treatment with MA was found to dose-dependently inhibit VEGF-A-stimulated angiogenesis after 10 days of incubation. We speculate that the presence of MA in cartilage is related to its vessel-free status, which is associated with local EFA deficiency that in turn leads to the stimulation of MA synthesis. The presence of MA in cartilage may also be important for the prevention of calcification. These mechanisms may also occur in other avascular tissues, such as the cornea and lens.
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inhibitory effect of 5 8 11 Eicosatrienoic Acid on angiogenesis
Prostaglandins Leukotrienes and Essential Fatty Acids, 2012Co-Authors: Tomohito Hamazaki, Tetsuro Nagasawa, Kei Hamazaki, Miho ItomuraAbstract:Abstract Introduction Cartilage contains high levels of n-9 Eicosatrienoic Acid (20:3n-9) but no blood vessels. 20:3n-9 might inhibit angiogenesis. Materials and methods Angiogenesis was measured in human umbilical vein endothelial cells and diploid fibroblasts. Co-culture was performed with vascular endothelial growth factor-A (VEGF-A, 10 ng/mL) and fatty Acids (0.1–10 μmol/L). After 10 days of incubation and immunostaining for endothelial cells, vessel areas were calculated with image analyser software. Results Addition of 20:3n-9 and n-3 Eicosatrienoic Acid (20:3n-3) dose dependently inhibited VEGF-A-stimulated angiogenesis (more than the positive control suramin). Arachidonic, eicosapentaenoic, dihomo-γ-linolenic (20:3n-6) and oleic Acids did not affect VEGF-A-stimulated angiogenesis even at 10 μmol/L. Arachidonic and dihomo-γ-linolenic Acids enhanced angiogenesis without VEGF-A. Discussion and conclusions We suggest that the presence of 20:3n-9 in cartilage may be related to its vessel-free status and that 20:3n-9 may be useful for the treatment of disorders with excessive vasculature. Acknowledgements This work was partly supported by Polyene Project, Inc.
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The Depressive Effects of 5,8,11-Eicosatrienoic Acid (20:3n-9) on Osteoblasts
Lipids, 2009Co-Authors: Tomohito Hamazaki, Nobuo Suzuki, Retno Widyowati, Tatsuro Miyahara, Shigetoshi Kadota, Hiroshi Ochiai, Kei HamazakiAbstract:In cases of essential fatty Acid deficiency, 5,8,11-Eicosatrienoic Acid (Mead Acid, 20:3n-9) is synthesized from oleic Acid as a 20-carbon analog of arachidonic Acid. It was reported that 20:3n-9 levels were markedly higher in human fetal cartilage than in the muscle, liver and spleen. We, therefore, hypothesized that 20:3n-9 decreased osteoblastic activity. Goldfish scales were incubated either with 20:3n-9 or with oleic Acid at 15 °C for 6 and 18 h. Both osteoblastic and osteoclastic activities in the scale were assessed by measuring alkaline phosphatase (ALP) and tartrate-resistant Acid phosphatase, respectively. MC3T3-E1 cells (an osteoblast cell line derived from the mouse) were incubated with 20:3n-9 or oleic Acid at 37 °C for 6 and 18 h. ALP activity in cell lysate was measured. In the case of experiments with scales, 20:3n-9 (1–100 μM) significantly suppressed osteoblastic activity after 6 and 18 h of incubation, whereas oleic Acid did not change this activity. Osteoclastic activity was not affected either by 20:3n-9 or by oleic Acid. In the case with the cell line, osteoblastic activity was again significantly decreased with 20:3n-9 (10–30 μM) after 6-h incubation but not after 18 h incubation. The presence of 20:3n-9 in fetal cartilage may be important for the prevention of calcification in the cartilage. 20:3n-9 could be applied to some clinical situations where bone formation should be inhibited.
John R Falck - One of the best experts on this subject based on the ideXlab platform.
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a biosynthetic pathway generating 12 hydroxy 5 8 14 Eicosatrienoic Acid from arachidonic Acid is active in mouse skin microsomes
Journal of Pharmacology and Experimental Therapeutics, 2006Co-Authors: Liping Du, John R Falck, Valery Yermalitsky, David L Hachey, Setti G Jagadeesh, Diane S KeeneyAbstract:The epidermis expresses cyclooxygenases, lipoxygenases, and cytochromes P450, which utilize arachidonic Acid to generate a diverse array of lipid mediators affecting epidermal cellular differentiation and functions. Recent studies show that mouse epidermis expresses CYP2B19, a keratinocyte-specific epoxygenase that generates 11,12- and 14,15-epoxyEicosatrienoic (EET) Acids from arachidonate. We studied CYP2B19-dependent metabolism in mouse epidermal microsomes, reconstituted in the presence of [1-14C]arachidonic Acid. The majority of the 14C products formed independently of NADPH, indicative of robust epidermal cyclooxygenase and lipoxygenase activities. We studied two NADPH-dependent products generated in a highly reproducible manner from arachidonate. One of these (product I) coeluted with the CYP2B19 product 14,15-EET on a reversed-phase high-performance liquid chromatography (HPLC) system; there was no evidence for other regioisomeric EET products. Further analyses proved that product I was not an epoxy fatty Acid, based on different retention times on a normal-phase HPLC system and failure of product I to undergo hydrolysis in Acidic solution. We analyzed purified epidermal 14C products by liquid chromatography negative electrospray ionization mass spectrometry. Structures of the NADPH-dependent products were confirmed to be 12-oxo-5,8,14-Eicosatrienoic Acid (I) and 12-hydroxy-5,8,14-Eicosatrienoic Acid (II). This was the first evidence for a 12-hydroxy-5,8,14-Eicosatrienoic Acid biosynthetic pathway in mouse epidermis. Epidermal microsomes also generated 12-hydroperoxy, 12-hydroxy, and 12-oxo eicosatetraenoic Acids from arachidonate, possible intermediates in the 12-hydroxy-5,8,14-Eicosatrienoic Acid biosynthetic pathway. These results predict that hydroxyEicosatrienoic Acids are synthesized from arachidonate in human epidermis. This would have important implications for human skin diseases given the known pro- and anti-inflammatory activities of stereo- and regioisomeric hydroxyEicosatrienoic Acids.
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enhancement of delayed hypersensitivity inflammatory reactions in guinea pig skin by 12 r hydroxy 5 8 14 Eicosatrienoic Acid
Journal of Investigative Dermatology, 1995Co-Authors: Michael S Conners, John R Falck, Michal L Schwartzman, X I N Quan, Edward Heilman, Kamlesh R Chauhan, Henry P GodfreyAbstract:Delayed-type hypersensitivity (DTH) reactions are initiated by sensitized T cells. Their progression is dependent upon the local release of various autacoids, including cytokines and eicosanoids, by T cells, infiltrating inflammatory cells, and resident tissue cells. 12(R)-hydroxy-5,8,14-Eicosatrienoic Acid [12(R)-HETrE], an cicosanoid produced by skin and cornea, possesses potent proinflammatory properties at picomolar concentrations including vasodilation, increase in membrane permeability, neutrophil chemotaxis, and angiogenesis. Because DTH reactions are associated with many of these same phenomena, we examined the effect of 12(R)-HETrE and related 12-hydroxyeicosanoids on the expression of DTH to purified protein derivative of tuberculin in sensitized guinea pigs. In the absence of purified protein derivative of tuberculin, none of the eicosanoids evoked erythema or edema after intradermal injection at doses up to 100 pmol. When injected together with purified protein derivative of tuberculin, 12(R)-hydroxy-5,8,10,14-eicosatetraenoic Acid [12(R)-HETE], but not its enantiomer 12(S)-HETE, significantly inhibited macroscopic expression of delayed reactivity (erythema) only at the highest dose tested, 10 pmol. In contrast, 12(R)-HETrE significantly enhanced expression of DTH at doses between 1 fmol and 1 pmol (50% and 30% increases above control, respectively). Its stereoisomer, 12(S)-HETrE, did not enhance DTH at any tested dose, but was able to block the activity of 12 (R)-HETrE when injected simultaneously. Enhancement or inhibition of visible skin responses was not associated with qualitative or quantitative changes in cellular infiltrates at the reaction site. 12(R)-HETrE had no effect on the nonimmunologic inflammatory skin reaction induced by phorbol myristate acetate, suggesting selectivity toward DTH. We conclude that 12(R)-HETrE enhances DTH via a yet to be determined mechanism and that its stereo-isomer, 12(S)-HETrE, may be a useful antagonist for studying the inflammatory actions of this eicosanoid.
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14 15 cis episulfide Eicosatrienoic Acid an epoxygenase eicosanoid analog inhibits ionophore but not thrombin induced platelet aggregation
Molecular Pharmacology, 1991Co-Authors: K Bernstrom, K Malcolm, J Mcgee, J Maclouf, S Levytoledano, John R Falck, F A FitzpatrickAbstract:An 9epoxygenase9 eicosanoid analog, 14, 15-cis-episulfide-Eicosatrienoic Acid, has several unique pharmacological effects on platelets. These include (i) inhibition of ionophore A23187- but not thrombin-induced activation, (ii) inhibition of thromboxane B2 biosynthesis derived from endogenous but not exogenous arachidonic Acid, and (iii) attenuation of ionophore-mediated increases in cytosolic Ca2+ when extracellular or membrane Ca2+ is available but not when these pools are excluded. Neither elevation of cyclic AMP levels, a potent inhibitory process, nor direct antagonism of the prostaglandin H2/thromboxane A2 receptor is responsible for the actions of 14, 15-cis-episulfide-Eicosatrienoic Acid. These properties distinguish 14, 15-cis-episulfide-Eicosatrienoic Acid from other antiaggregatory substances.
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Metabolism of 12(S)-hydroxy-5,8,10,14-eicosatetraenoic Acid and other hydroxylated fatty Acids by the reductase pathway in porcine polymorphonuclear leukocytes
Biochemistry, 1990Co-Authors: Sandra Wainwright, John R Falck, Pendri Yadagiri, William S PowellAbstract:We have previously shown that porcine polymorphonuclear leukocytes (PMNL) reduce leukotriene B4 (LTB4) to 10,11-dihydro-LTB4, 10,11-dihydro-12-epi-LTB4, and 10,11-dihydro-12-oxo-LTB4 [Wainwright et al. (1990) Biochemistry 29, 1180-1185]. We have now demonstrated that 12(S)-hydroxy-5,8,10,14-eicosatetraenoic Acid [12(S)-HETE] is metabolized by a similar pathway in porcine PMNL. 12(S)-HETE was metabolized to two products that were identified by gas chromatography-mass spectrometry and nuclear magnetic resonance spectroscopy as 12-hydroxy-5,8,14-Eicosatrienoic Acid (10,11-dihydro-12-HETE) and 12-oxo-5,8,14-Eicosatrienoic Acid (10,11-dihydro-12-oxo-ETE). Derivatization of 12-hydroxy-5,8,14-Eicosatrienoic Acid with (R)-(+)-alpha-methoxy-alpha-(trifluoromethyl)phenylacetic Acid, followed by chromatography on a silicic Acid column, enabled the resolution of 12R and 12S stereoisomers, which were identified by cochromatography with synthetic standards. Incubation of 12(S)-HETE with PMNL for various times revealed that the stereochemistry of the 12-hydroxyl group of 12-hydroxy-5,8,14-Eicosatrienoic Acid was initially the same as that of 12(S)-HETE. However, after 40 min, 30% of the 12-hydroxy-5,8,14-Eicosatrienoic Acid had the opposite configuration at C12. 13-Hydroxy-9,11-octadecadienoic Acid (13-HODE) was metabolized in a similar fashion by porcine PMNL to 13-hydroxy-9-octadecenoic Acid (11,12-dihydro-13-HODE) and 13-oxooctadecenoic Acid (11,12-dihydro-13-oxo-ODE). The apparent Km values for the reduction of 12-HETE, LTB4, and 13-HODE were 0.21, 0.28, and 2.22 microM, respectively. All three substrates had the same apparent Vmax [0.029 pmol min-1 (10(6) cells)-1]. Competition experiments between LTB4 and 12-HETE indicated that they were metabolized by the same pathway. Various structurally related compounds were metabolized by porcine PMNL in the order LTB4 = 6-trans-LTB4 greater than 12-epi-6-trans,8-cis-LTB4 greater than 12-epi-6-trans-LTB4 greater than 12-HETE greater than LTB5 greater than 15-HETE = 13-HODE much greater than 5-HETE greater than 9-HODE greater than 20-hydroxy-LTB4 greater than 12-hydroxy-5,8,10-heptadecatrienoic Acid. Prostaglandins E2 and F2 alpha were not metabolized to any detectable products by porcine PMNL.
Kei Hamazaki - One of the best experts on this subject based on the ideXlab platform.
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what are the physiological roles of mead Acid 5 8 11 Eicosatrienoic Acid
2016Co-Authors: Tomohito Hamazaki, Kei HamazakiAbstract:Abstract In this chapter we explore the physiological effects of Mead Acid (5,8,11-Eicosatrienoic Acid, MA) on osteoblasts and osteoclasts in Part 1 and then on angiogenesis in Part 2. Part 1: MA (5,8,11-Eicosatrienoic Acid) is actively synthesized only in the essential fatty Acid (EFA)-deficient state, and until recently the roles of MA in the normal state had not been investigated. Concentrations of MA have long been known to be high in the cartilage of chicken and human infants, even without EFA deficiency. Based on these facts, we postulated that MA prevents the calcification of cartilage. To investigate this possibility, we treated goldfish scales, which served as a source of both osteoblasts and osteoclasts, with MA or oleic Acid for 6 and 18 h at 15 °C. Osteoblastic and osteoclastic activities in the scales were assessed by measuring alkaline phosphatase (ALP) and tartrate-resistant Acid phosphatase activities, respectively. Osteoblastic activity was also evaluated in MC3T3-E1 cells (a murine osteoblast cell line) by incubating cells with MA or oleic Acid for 6 and 18 h at 37 °C and then measuring ALP activity in cell lysate. In the scales, MA (1–102 μmol/L) significantly suppressed ALP after 6 and 18 h of incubation, whereas oleic Acid had no effect on ALP activity. Osteoclastic activity was not affected by either MA or oleic Acid. In the MC3T3-E1 cell line, osteoblastic activity was also significantly decreased by treatment with MA (3–30 μmol/L) for 6 h but not for 18 h. Part 2: Cartilage contains no blood vessels, a condition that likely leads to local EFA deficiency and the synthesis of MA. Why is cartilage an avascular tissue? Is the avascular state supported by MA? If MA inhibits angiogenesis in cartilage, this fatty Acid might support its own synthesis in avascular tissues, namely, MA→avascularity→EFA deficiency→MA synthesis. To examine this possibility, angiogenesis was measured in a coculture system consisting of human umbilical vein endothelial cells and diploid fibroblasts with exogenously added vascular endothelial growth factor-A (VEGF-A, 10 ng/mL) and fatty Acids (0.1–10 μmol/L). Vessel areas were calculated using image analysis software. Treatment with MA was found to dose-dependently inhibit VEGF-A-stimulated angiogenesis after 10 days of incubation. We speculate that the presence of MA in cartilage is related to its vessel-free status, which is associated with local EFA deficiency that in turn leads to the stimulation of MA synthesis. The presence of MA in cartilage may also be important for the prevention of calcification. These mechanisms may also occur in other avascular tissues, such as the cornea and lens.
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Chapter 17 – What Are the Physiological Roles of Mead Acid (5,8,11-Eicosatrienoic Acid)?*
Handbook of Lipids in Human Function, 2016Co-Authors: Tomohito Hamazaki, Kei HamazakiAbstract:In this chapter we explore the physiological effects of Mead Acid (5,8,11-Eicosatrienoic Acid, MA) on osteoblasts and osteoclasts in Part 1 and then on angiogenesis in Part 2. Part 1: MA (5,8,11-Eicosatrienoic Acid) is actively synthesized only in the essential fatty Acid (EFA)-deficient state, and until recently the roles of MA in the normal state had not been investigated. Concentrations of MA have long been known to be high in the cartilage of chicken and human infants, even without EFA deficiency. Based on these facts, we postulated that MA prevents the calcification of cartilage. To investigate this possibility, we treated goldfish scales, which served as a source of both osteoblasts and osteoclasts, with MA or oleic Acid for 6 and 18 h at 15 °C. Osteoblastic and osteoclastic activities in the scales were assessed by measuring alkaline phosphatase (ALP) and tartrate-resistant Acid phosphatase activities, respectively. Osteoblastic activity was also evaluated in MC3T3-E1 cells (a murine osteoblast cell line) by incubating cells with MA or oleic Acid for 6 and 18 h at 37 °C and then measuring ALP activity in cell lysate. In the scales, MA (1–102 μmol/L) significantly suppressed ALP after 6 and 18 h of incubation, whereas oleic Acid had no effect on ALP activity. Osteoclastic activity was not affected by either MA or oleic Acid. In the MC3T3-E1 cell line, osteoblastic activity was also significantly decreased by treatment with MA (3–30 μmol/L) for 6 h but not for 18 h. Part 2: Cartilage contains no blood vessels, a condition that likely leads to local EFA deficiency and the synthesis of MA. Why is cartilage an avascular tissue? Is the avascular state supported by MA? If MA inhibits angiogenesis in cartilage, this fatty Acid might support its own synthesis in avascular tissues, namely, MA→avascularity→EFA deficiency→MA synthesis. To examine this possibility, angiogenesis was measured in a coculture system consisting of human umbilical vein endothelial cells and diploid fibroblasts with exogenously added vascular endothelial growth factor-A (VEGF-A, 10 ng/mL) and fatty Acids (0.1–10 μmol/L). Vessel areas were calculated using image analysis software. Treatment with MA was found to dose-dependently inhibit VEGF-A-stimulated angiogenesis after 10 days of incubation. We speculate that the presence of MA in cartilage is related to its vessel-free status, which is associated with local EFA deficiency that in turn leads to the stimulation of MA synthesis. The presence of MA in cartilage may also be important for the prevention of calcification. These mechanisms may also occur in other avascular tissues, such as the cornea and lens.
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chapter 17 what are the physiological roles of mead Acid 5 8 11 Eicosatrienoic Acid
Handbook of Lipids in Human Function#R##N#Fatty Acids, 2016Co-Authors: Tomohito Hamazaki, Kei HamazakiAbstract:In this chapter we explore the physiological effects of Mead Acid (5,8,11-Eicosatrienoic Acid, MA) on osteoblasts and osteoclasts in Part 1 and then on angiogenesis in Part 2. Part 1: MA (5,8,11-Eicosatrienoic Acid) is actively synthesized only in the essential fatty Acid (EFA)-deficient state, and until recently the roles of MA in the normal state had not been investigated. Concentrations of MA have long been known to be high in the cartilage of chicken and human infants, even without EFA deficiency. Based on these facts, we postulated that MA prevents the calcification of cartilage. To investigate this possibility, we treated goldfish scales, which served as a source of both osteoblasts and osteoclasts, with MA or oleic Acid for 6 and 18 h at 15 °C. Osteoblastic and osteoclastic activities in the scales were assessed by measuring alkaline phosphatase (ALP) and tartrate-resistant Acid phosphatase activities, respectively. Osteoblastic activity was also evaluated in MC3T3-E1 cells (a murine osteoblast cell line) by incubating cells with MA or oleic Acid for 6 and 18 h at 37 °C and then measuring ALP activity in cell lysate. In the scales, MA (1–102 μmol/L) significantly suppressed ALP after 6 and 18 h of incubation, whereas oleic Acid had no effect on ALP activity. Osteoclastic activity was not affected by either MA or oleic Acid. In the MC3T3-E1 cell line, osteoblastic activity was also significantly decreased by treatment with MA (3–30 μmol/L) for 6 h but not for 18 h. Part 2: Cartilage contains no blood vessels, a condition that likely leads to local EFA deficiency and the synthesis of MA. Why is cartilage an avascular tissue? Is the avascular state supported by MA? If MA inhibits angiogenesis in cartilage, this fatty Acid might support its own synthesis in avascular tissues, namely, MA→avascularity→EFA deficiency→MA synthesis. To examine this possibility, angiogenesis was measured in a coculture system consisting of human umbilical vein endothelial cells and diploid fibroblasts with exogenously added vascular endothelial growth factor-A (VEGF-A, 10 ng/mL) and fatty Acids (0.1–10 μmol/L). Vessel areas were calculated using image analysis software. Treatment with MA was found to dose-dependently inhibit VEGF-A-stimulated angiogenesis after 10 days of incubation. We speculate that the presence of MA in cartilage is related to its vessel-free status, which is associated with local EFA deficiency that in turn leads to the stimulation of MA synthesis. The presence of MA in cartilage may also be important for the prevention of calcification. These mechanisms may also occur in other avascular tissues, such as the cornea and lens.
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inhibitory effect of 5 8 11 Eicosatrienoic Acid on angiogenesis
Prostaglandins Leukotrienes and Essential Fatty Acids, 2012Co-Authors: Tomohito Hamazaki, Tetsuro Nagasawa, Kei Hamazaki, Miho ItomuraAbstract:Abstract Introduction Cartilage contains high levels of n-9 Eicosatrienoic Acid (20:3n-9) but no blood vessels. 20:3n-9 might inhibit angiogenesis. Materials and methods Angiogenesis was measured in human umbilical vein endothelial cells and diploid fibroblasts. Co-culture was performed with vascular endothelial growth factor-A (VEGF-A, 10 ng/mL) and fatty Acids (0.1–10 μmol/L). After 10 days of incubation and immunostaining for endothelial cells, vessel areas were calculated with image analyser software. Results Addition of 20:3n-9 and n-3 Eicosatrienoic Acid (20:3n-3) dose dependently inhibited VEGF-A-stimulated angiogenesis (more than the positive control suramin). Arachidonic, eicosapentaenoic, dihomo-γ-linolenic (20:3n-6) and oleic Acids did not affect VEGF-A-stimulated angiogenesis even at 10 μmol/L. Arachidonic and dihomo-γ-linolenic Acids enhanced angiogenesis without VEGF-A. Discussion and conclusions We suggest that the presence of 20:3n-9 in cartilage may be related to its vessel-free status and that 20:3n-9 may be useful for the treatment of disorders with excessive vasculature. Acknowledgements This work was partly supported by Polyene Project, Inc.
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The Depressive Effects of 5,8,11-Eicosatrienoic Acid (20:3n-9) on Osteoblasts
Lipids, 2009Co-Authors: Tomohito Hamazaki, Nobuo Suzuki, Retno Widyowati, Tatsuro Miyahara, Shigetoshi Kadota, Hiroshi Ochiai, Kei HamazakiAbstract:In cases of essential fatty Acid deficiency, 5,8,11-Eicosatrienoic Acid (Mead Acid, 20:3n-9) is synthesized from oleic Acid as a 20-carbon analog of arachidonic Acid. It was reported that 20:3n-9 levels were markedly higher in human fetal cartilage than in the muscle, liver and spleen. We, therefore, hypothesized that 20:3n-9 decreased osteoblastic activity. Goldfish scales were incubated either with 20:3n-9 or with oleic Acid at 15 °C for 6 and 18 h. Both osteoblastic and osteoclastic activities in the scale were assessed by measuring alkaline phosphatase (ALP) and tartrate-resistant Acid phosphatase, respectively. MC3T3-E1 cells (an osteoblast cell line derived from the mouse) were incubated with 20:3n-9 or oleic Acid at 37 °C for 6 and 18 h. ALP activity in cell lysate was measured. In the case of experiments with scales, 20:3n-9 (1–100 μM) significantly suppressed osteoblastic activity after 6 and 18 h of incubation, whereas oleic Acid did not change this activity. Osteoclastic activity was not affected either by 20:3n-9 or by oleic Acid. In the case with the cell line, osteoblastic activity was again significantly decreased with 20:3n-9 (10–30 μM) after 6-h incubation but not after 18 h incubation. The presence of 20:3n-9 in fetal cartilage may be important for the prevention of calcification in the cartilage. 20:3n-9 could be applied to some clinical situations where bone formation should be inhibited.
Ernst H Oliw - One of the best experts on this subject based on the ideXlab platform.
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oxygenation of 5 8 11 Eicosatrienoic Acid by prostaglandin h synthase 2 of ovine placental cotyledons isolation of 13 hydroxy 5 8 11 Eicosatrienoic and 11 hydroxy 5 8 12 Eicosatrienoic Acids
Journal of Chromatography B: Biomedical Sciences and Applications, 1997Co-Authors: Ernst H Oliw, Lena Hornsten, Howard SprecherAbstract:Oxygenation of 5,8,11-Eicosatrienoic Acid by prostaglandin H synthase-2 ofovine placental cotyledons: isolation of 13-hydroxy-5,8,11-Eicosatrienoicand 11-hydroxy-5,8,12-Eicosatrienoic Acids.
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oxygenation of 5 8 11 Eicosatrienoic Acid by prostaglandin endoperoxide synthase and by cytochrome p450 monooxygenase structure and mechanism of formation of major metabolites
Archives of Biochemistry and Biophysics, 1993Co-Authors: Ernst H Oliw, Lena Hornsten, Howard Sprecher, Mats HambergAbstract:Abstract Incubation of 5,8,11-[1- 14 C]Eicosatrienoic Acid with prostaglandin endoperoxide synthase of ram vesicular gland microsomes led to formation of a number of polar metabolites. Four major compounds were characterized by chemical and physical methods and found to be: (13 R )-hydroxy-5,8,11-Eicosatrienoic Acid, (11 R )-hydroxy-5,8,12-Eicosatrienoic Acid, 8,9,11-trihydroxy-5,12-eicosadienoic Acid (two diastereoisomers), and 8,9-epoxy-11-hydroxy-5,12-eicosadienoic Acid. On the basis of previous studies on the mechanism of prostaglandin biosynthesis it seemed likely that the initial step of conversion of 5,8,11-Eicosatrienoic Acid consisted of removal of the pro-S hydrogen from C-13. The resulting carbon-centered radical was apparently attacked by dioxygen at C-13 to provide a (13 R )-(hydro)peroxy derivative, which served as the precursor of (13 R )-hydroxyEicosatrienoic Acid. Alternatively, attack by dioxygen occurred at C-11 to produce an (11 R )-peroxy radical. This intermediate was further converted to (11 R )-hydroxyEicosatrienoic Acid by reduction, into two 8,9,11-trihydroxy-5,12-eicosadienoic Acids by successive cyclization, oxygenation, and reduction, and into the epoxy-hydroxy Acid by cyclization and intramolecular epoxidation. The relative abundance of (13 R )-hydroxy-5,8,11-Eicosatrienoic Acid, (11 R )-hydroxy-5,8,12-Eicosatrienoic Acid, and the epoxy alcohol plus the two 8,9,11-triols was 51, 9, and 40%, respectively. The oxygenation at C-13 and C-11 of 5,8,11-Eicosatrienoic Acid was inhibited by 90% in the presence of diclofenac, an inhibitor of prostaglandin endoperoxide synthase. The two diastereomeric 8,9,11-trihydroxy Acids and the epoxy-hydroxy Acid are novel oxylipins and their formation provides independent chemical evidence for the existence of an 11-peroxy radical intermediate in prostaglandin endoperoxide synthase catalysis. Oxygenation of 5,8,11-Eicosatrienoic Acid by cytochrome P450 from liver microsomes of cynomolgus monkeys and phenobarbital-treated rats was also investigated. The metabolites formed included 19- and 20-hy-droxyEicosatrienoic Acid, 8,9- and 11,12-dihydroxyeicosadienoic Acids (formed by enzymatic hydrolysis of the corresponding epoxides), and (12 R )-hydroxy-5,8,10-hydroxyEicosatrienoic Acid.
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production of 5 8 11 Eicosatrienoic Acid by a δ5 and δ6 desaturation activity enhanced mutant derived from a δ12 desaturation activity defective mutant of mortierella alpina 1s 4
Applied Microbiology and Biotechnology, 2002Co-Authors: Eiji Sakuradani, Hiroshi Kawashima, Kengo Akimoto, Nozomu Kamada, Yuriko Hirano, M Nishihara, Kenichi Higashiyama, Jun Ogawa, Sakayu ShimizuAbstract:Enhanced production of 5,8,11-Eicosatrienoic Acid (Mead Acid, 20:3ω9) was attained with a mutant fungus, Mortierella alpina JT-180, derived from Δ12 desaturation activity-defective and Δ6 desaturation activity-enhanced M. alpina M209–7. Production of 20:3ω9 by JT-180 was 1.4 times greater than that of the parent strain M209–7. This is thought to be due to its enhanced Δ5 desaturation activity, which was 3.3 times higher than that of M209–7. In both strains, 78.5–80.4% of the total lipids comprised triacylglycerol (TG), and 76.6–79.0% of 20:3ω9 was present in TG. Comparing the fatty Acid compositions among various lipid species, the highest percentages (24.1–37.6%) of 20:3ω9 in total lipids were found in phosphatidylcholine. For optimization of 20:3ω9 production by JT-180, a glucose concentration of 4% in the culture medium and shifting of the growth temperature from 28°C to 20°C on the 2nd day were shown to be effective. Under optimal conditions, 20:3ω9 production by JT-180 reached 1.92 g/l culture medium in a 10-l jar fermentor (corresponding to 81.5 mg/g dry mycelia and 18.3% of total fatty Acids), which is greater than that reported previously from M209–7 (1.65 g/l).
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production of 5 8 11 Eicosatrienoic Acid mead Acid by a delta 6 desaturation activity enhanced mutant derived from a delta 12 desaturase defective mutant of an arachidonic Acid producing fungus mortierella alpina 1s 4
Applied and Environmental Microbiology, 1997Co-Authors: Hiroshi Kawashima, Kengo Akimoto, Nozomu Kamada, Yuriko Hirano, M Nishihara, Kyoko Konishi, Sakayu ShimizuAbstract:Enhanced production of 5,8,11-Eicosatrienoic Acid (Mead Acid, 20:3(omega)9) was attained by a mutant fungus, Mortierella alpina M209-7, derived from (Delta)12 desaturase-defective M. alpina Mut48. The 20:3(omega)9 production by M209-7 was 1.3 times greater than that by its parent strain, Mut48. This is thought to be due to its enhanced (Delta)6 desaturation activity, which was 1.4 times higher than that of Mut48. In both strains, 87 to 88% of the total lipids comprised triacylglycerol (TG) and 85% of 20:3(omega)9 was contained in TG. On optimization of the culture conditions for M209-7, earlier glucose feeding and shifting of the growth temperature from 28 to 19(deg)C on the second day were shown to be effective. Under the optimal conditions with a 10-liter jar fermentor, 20:3(omega)9 production reached 1.65 g/liter of culture medium (corresponding to 118 mg/g of dry mycelia and 28.9% of total fatty Acids), which is about twice that reported previously (0.8 g/liter).
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production of 5 8 11 cis Eicosatrienoic Acid by a δ12 desaturase defective mutant ofmortierella alpina 1s 4
Journal of the American Oil Chemists' Society, 1992Co-Authors: Saeree Jareonkitmongkol, Hiroshi Kawashima, Sakayu Shimizu, Hideaki YamadaAbstract:A mutant defective in Δ12-desaturase of an arachidonic-Acid producing fungus,Mortierella alpina 1S-4, was shown to be a novel potent producer of Mead Acid (5,8,11-cis-Eicosatrienoic Acid, 20:3ω9). The fungus produced several fatty Acids of the n-9 family,i.e., 6,9-cis-octadecadienoic Acid (18:2ω9), 8,11-cis-eicosadienoic Acid (20:2ω9) and 20:3ω9. Significantly high levels of these fatty Acids were produced during growth at low temperatures (12–20°C). On submerged cultivation at 20°C for 10 days in a 5-L fermenter containing 2% glucose plus 1% yeast extract (pH 6.0), the production of 20:3ω9 reachedca. 0.8 g/L (56 mg/g dry mycelia), accounting for 15% (by wt) of the total mycelial fatty Acids. The other major fatty Acids were palmitic Acid (6%), stearic Acid (11%), oleic Acid (45%), 18:2ω9 (12%) and 20:2ω9 (3%). Studies on the distribution of fatty Acids among lipid classes showed that, irrespective of the growth temperature employed (12–28°C),ca. 70% (by mol) of 20:3ω9 was present in the triglyceride and the remainder in the phospholipid fraction, especially in phosphatidylcholine (PC). When the fungus was grown at 12°C, the proportion of 20:3ω9 in the PC fraction wasca. 55%.