Elucidation of the Molecular Actions of 1,25 Dihydroxyvitamin D3 and Docosahexaenoic Acid that may Mediate Cardiovascular Health

Widener, Tim

dc.contributor.author	Widener, Tim
dc.date.accessioned	2013-04-17T18:48:20Z
dc.date.available	2013-04-17T18:48:20Z
dc.date.issued	2013-03
dc.identifier.uri	http://hdl.handle.net/10150/281812
dc.description	A Thesis submitted to The University of Arizona College of Medicine - Phoenix in partial fulfillment of the requirements for the Degree of Doctor of Medicine.	en
dc.description.abstract	Omega 3 polyunsaturated fatty acids (PUFAs), composed of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have been demonstrated to be beneficial in primary and secondary cardiovascular disease (CVD) prevention. The mechanism of action of PUFAs is not yet fully understood. Vitamin D, via its active form, 1,25-dihydroxyvitamin D3 (1,25 D3), functions through the vitamin D receptor (VDR), regulating serum calcium and phosphorus, and ultimately bone health. There is now evidence that 1,25 D3 may be cardioprotective as well, but the mechanism is also not fully understood. Evidence supports DHA as a weak VDR agonist, therefore there may be crosstalk between the two ligands and their known and yet to be discovered receptors. In the present research, we probed six genes as potential VDR targets, identified both through literature searches as well as their logical association with proposed 1,25 D3 and DHA cardioprotective mechanisms. Treating human embryonic kidney cells (HEK293) with 1,25 D3 and DHA independently, and in combination, we demonstrate changes of expression of three genes through quantitative real time polymerase chain reaction analysis (qRT-PCR). Nitric oxide synthase (NOS2), involved in the immune system nitric oxide burst, was significantly repressed by 1,25 D3 (fold effect 0.84, p value 0.04), DHA (fold effect 0.85, p value <0.01), with the greatest repression in the 1,25 D3 and DHA combination (fold effect 0.74, p value 0.01). Serpin peptidase inhibitor (SERPINE1), for which expression results in increased thrombus formation through tissue plasminogen activator inhibition, was repressed in the 1,25 D3 treatment group (fold effect 0.78, p value <0.01). Thrombomodulin (THBD), which indirectly activates protein C and increases thrombolysis, was repressed in the DHA (fold effect 0.69, p value <0.01) and combination 1,25 D3 and DHA groups (fold effect 0.75, p value 0.04). SERPINE1 and NOS2 repression is consistent with cardioprotective decreases in thrombus formation and immunomodulation, but THBD repression is not consistent with this hypothesis.
dc.language.iso	en_US	en
dc.publisher	The University of Arizona.	en_US
dc.rights	Copyright © is held by the author. Digital access to this material is made possible by the College of Medicine - Phoenix, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.	en_US
dc.subject.mesh	Vitamin D	en
dc.subject.mesh	Cardiovascular System	en
dc.subject.mesh	Fatty Acids, Omega-3	en
dc.subject.mesh	Docosahexaenoic Acids	en
dc.title	Elucidation of the Molecular Actions of 1,25 Dihydroxyvitamin D3 and Docosahexaenoic Acid that may Mediate Cardiovascular Health	en_US
dc.type	text; Electronic Thesis	en
dc.contributor.department	The University of Arizona College of Medicine - Phoenix	en
dc.description.collectioninformation	This item is part of the College of Medicine - Phoenix Scholarly Projects 2013 collection. For more information, contact the Phoenix Biomedical Campus Library at pbc-library@email.arizona.edu.	en_US
dc.contributor.mentor	Jurutka, Peter	en
dc.contributor.mentor	Haussler, Mark	en
refterms.dateFOA	2018-06-27T10:42:05Z
html.description.abstract	Omega 3 polyunsaturated fatty acids (PUFAs), composed of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have been demonstrated to be beneficial in primary and secondary cardiovascular disease (CVD) prevention. The mechanism of action of PUFAs is not yet fully understood. Vitamin D, via its active form, 1,25-dihydroxyvitamin D3 (1,25 D3), functions through the vitamin D receptor (VDR), regulating serum calcium and phosphorus, and ultimately bone health. There is now evidence that 1,25 D3 may be cardioprotective as well, but the mechanism is also not fully understood. Evidence supports DHA as a weak VDR agonist, therefore there may be crosstalk between the two ligands and their known and yet to be discovered receptors. In the present research, we probed six genes as potential VDR targets, identified both through literature searches as well as their logical association with proposed 1,25 D3 and DHA cardioprotective mechanisms. Treating human embryonic kidney cells (HEK293) with 1,25 D3 and DHA independently, and in combination, we demonstrate changes of expression of three genes through quantitative real time polymerase chain reaction analysis (qRT-PCR). Nitric oxide synthase (NOS2), involved in the immune system nitric oxide burst, was significantly repressed by 1,25 D3 (fold effect 0.84, p value 0.04), DHA (fold effect 0.85, p value <0.01), with the greatest repression in the 1,25 D3 and DHA combination (fold effect 0.74, p value 0.01). Serpin peptidase inhibitor (SERPINE1), for which expression results in increased thrombus formation through tissue plasminogen activator inhibition, was repressed in the 1,25 D3 treatment group (fold effect 0.78, p value <0.01). Thrombomodulin (THBD), which indirectly activates protein C and increases thrombolysis, was repressed in the DHA (fold effect 0.69, p value <0.01) and combination 1,25 D3 and DHA groups (fold effect 0.75, p value 0.04). SERPINE1 and NOS2 repression is consistent with cardioprotective decreases in thrombus formation and immunomodulation, but THBD repression is not consistent with this hypothesis.