Project/Activity Title: N-3
Polyunsaturated fatty acids in human health and disease.
Period Covered:
Date of this report:
Annual Meeting Dates:
Participants: Kenneth G.D. Allen (Colorado State
University), Jennifer E.L. Anderson (Colorado State University), Mary A. Harris
(Colorado State University),
Members Absent: Debra Palmer-Keenan, (Rutgers), K. Shane Broughton (University of
Wyoming), Rosemary Wander (University of North Carolina, Greensboro), Daniel
Gallaher (University of Minnesota), Melvin Mathias (CSREES Representative,
Washington, DC).
The meeting was called to
order by Kenneth GD Allen, Chairman at
Mary A. Harris (
A CSREES report was submitted
by Melvin Mathias (CSREES Representative) and presented by Nancy Lewis. The report covered CSREES staff changes,
proposed funding for fiscal 2004, NRI funding update including proposed
integrated initiative in food safety and water quality. Changes may include a smaller number of
larger dollar awards up to 500K and longer term projects. Obesity RFP for FY03 is not out yet. Other CSREES emphasis areas include functional
foods and microconstituents included in bioactive food components, and gene-nutrient
interactions
Technical committee membership
was discussed by Ian Gray, Administrative Advisor. Issues included several members who have not
participated and/or submitted progress reports to demonstrate ongoing interest
in project; these are: Rosemary Wander (
Announcements:
Report
on IFT Symposium on dietary n6/n3 fatty acid balance presented at the IFT
Meeting in
Nutrition
Education Report
Nancy
Lewis reported the results of a survey of 10 RDs in each of 4 states. Report included
dietitian and client knowledge and sources of n3 information. A journal article is being prepared for
submission on what RDs know about n3 and their education needs. Trained
interviewers are ready to start collecting data.
The
first day meeting was adjourned at
The
second day meeting was called to order at
Collaborative
efforts of the basic science groups and nutrition education component were
discussed. The collaboration has
strengthened as the project progresses; the group is developing into a cohesive
core of n3 fatty acid studies. Collaborative efforts are in experimental
design, n-3 form and amount, investigations being done under a number of different
experimental conditions and the education of nutrition professionals. The result will be a general answer to a
fundamental question regarding the most important forms and amounts of dietary
n3 fatty acids for health maintenance and disease prevention which is
strengthened by documenting the effect in a number of different systems. In
addition, the nutrition education component will inform nutrition professionals
on these results for education of RDs and their clients.
The
feasibility of writing an NRI integrative proposal by this group was discussed.
Essentiality
of DHA. reviewed by
Individual
station reports were presented
Election
of officers was held. The next chairman
is Shane Broughton and secretary is Kevin Fritschie
The
meeting was adjourned at
Abbreviated State (Station) Reports for
NC-1167 Committee
|
Kenneth G.D. Allen (PI) Mary A. Harris (CoI) Department of |
Tel:(970)491-6712 Fax:(970)491-7252 |
We
investigated the importance of both the form and the amount of dietary n-3
polyunsaturated fatty acids (PUFA) on indices of gestational length and
premature delivery in rats. We constructed rat diets to provide relatively
constant linoleic acid (LA) which ranged from 5.4 to 6.3 energy (en) %,
containing either 0.7 en% n-3 PUFA or 2.0 en % PUFA as linolenic acid,
docosahexaenoic, or SDA. At day 20 of gestation uterine prostaglandin (PG) E2
and F2α synthesis rates were both significantly depressed
approximately 50% by both 0.7 en% and 2.0 en% DHA, but not by 2.0 en% LnA.
Placental collagenase activity (matrix metalloproteinase (MMP) 1, 8 and 13 activities)
was 50% depressed by 0.7 en % and 2.0 en% DHA and by 2.0 en% LnA. Placental
active MMP-2 and MMP-9 expression were 40% suppressed by 0.7 en% and 2.0 en%
DHA. Decreases in PG synthesis and MMP activity and expression are associated
with increased gestational length and reduced incidence of premature delivery.
Replacing LnA with DHA in diets, without increasing n-3 PUFA intakes from
current
|
K.
Shane Broughton (PI) Nutrition/Dept.
of Family and Consumer Sci. |
Tel:
(307)766-5248 Fax:
(307)766-5686 |
The influence of different forms of n-3 fatty acids, 2.2
energy% of the n-3 PUFA stearidonic acid
(SDA) and eicosapentaenoic acid (EPA) and conjugated linoleic acid (CLA on
ovulation and the expression of enzymes involved in ovulation. Sprague Dawley rats were maintained on a diet
that was isocaloric with a variation in the n-3 PUFA source, or consumed a
control diet or a diet enriched in conjugated linoleic acid (CLA). Following induction of ovulation with
pregnant mares serum gonadotropin followed by human chorionic gonadotropin, the
female rats were euthanized and the eggs in the oviduct were assayed along with
prostaglandin production and ovarian cyclooxygenase 1 and 2 (COX-1 and COX-2)
expression. While egg release did not
vary at this level of dietary lipid modification, COX-1 expression was
increased by 120% with SDA ingestion over control or EPA ingestion. Conversely, with CLA ingestion, COX-2
expression was reduced to 68% of that seen by the control and EPA animals. Prostaglandin release in correlation with COX
expression is under analysis.
|
Dept.
|
Tel:
(517)355-8474 Fax:
(517)353-8963 |
An
increasing number of studies have shown that inflammation plays a major role in
the development of cardiovascular diseases. IL-6, a proinflammatory cytokine,
is secreted from variety of cell types such as activated leukocytes,
endothelial cells, and adipocytes and is a potent inducer of hepatic C-reactive
protein (CRP), one of the most sensitive markers of CVD risk. Recent studies
also have demonstrated that adipose tissue releases large amounts of CRP
activator, IL-6, in vivo. We tested whether murine 3T3-L1 preadipocytes secret
significant levels of IL-6 when compared to differentiated 3T3-L1 adipocytes
and whether anti-inflammatory n-3 fatty acids such as EPA (20:5, n-3) and SDA
(18:4, n-3) inhibit lipopolysaccharide (LPS)-induced increases in IL-6
secretion in murine 3T3-L1 preadipocytes. Our data showed that preadipocytes
secrete significantly higher levels of IL-6 than adipocytes, and treatment of
preadipocytes with both EPA and SDA decreases LPS-induced IL-6 secretion
significantly by approximately 70%. We conclude that one way by which n-3 fatty
acids can reduce cardiovascular disease risk may be via down regulating IL-6 in
the preadipocytes.
|
Kevin
Fritsche (PI) Dept.
|
Tel:
(573)882-7240 Fax:
(573)882-6827 |
Cells of the
innate immune system (i.e. macrophages, natural
killer cells, neutrophils, dendritic cells) play a critical role in controlling
bacterial growth during the initial stages of infection. It is this stage of host defense that seems
most seriously impaired by LCn-3 PUFA, e.g. fish oil, as illustrated by the
reduced bacterial clearance we have observed in the liver and spleen 3 to 4
days post-infection. Changes in bacterial clearance correlate with lower
survival rates for mice consuming a high LCn-3 PUFA diet. We have some evidence that both LCn-3 PUFA
found in fish oils eicosapentaenoic
acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) are equally
effective at modulating host infectious disease resistance to this pathogen. We
have observed a significant adverse effect of LCn-3 PUFA at a level of intake
equivalent to ~2 energy%. This is about
10-fold higher than the current average intake of LCn-3 PUFA for people in the
U.S., however, it is not far from the levels that are currently being recommended
by some health professionals (i.e., 0.65 energy%). Current studies are investigating the level
of LCn-3 PUFA and the impact of various n-3 PUFA forms (alpha-linolenic,
stearidonic, EPA and DHA) on host infectious disease resistance.
|
Nancy M. Lewis (PI) Department of Nutritional
Sciences and Dietetics |
Tel: (402)472-4633 Fax: (402)472-1587 |
We
have designed and evaluated an omega-3 fatty acid nutrition education
intervention for heart patients and have shown that participants increased
their n-3 fatty acid intakes after receiving the education. We have also assessed the impact of
geographic region on omega-3 fatty acid intakes by surveying the intakes of elderly
men in two geographic regions (a coastal and an internal region) of
During
this past year, NC-1167 partners from Kansas, Colorado, New Jersey and Nebraska
have worked as a team to develop a detailed questionnaire for assessing omega-3
knowledge and practices of dietitians which was adapted for completion using
the web and this web survey was piloted with two dietitians from each state and
further refinements have been made. Our
plan at this time is to conduct the survey early in 2004 and to obtain
responses using both telephone and web-based surveys. Information gathered from these surveys will
provide a profile of baseline knowledge and practices of a random sample of
dietitians in these four states.
|
Barbara Lohse PhD, RD, LD Department of Human Nutrition |
Tel:
(785)532-0154 Fax:
(785)532-3132 |
Kansas
State University Extension Agents in the College of Human Ecology have been
teaching consumers about omega-3 fatty acids using the Lesson, “Omega-3s: Fats you Should and Can Eat,” written by
Barbara Lohse (Knous). A second omega-3
problem that encouraged menu planning was developed and the omega-3 website (www.oznet.ksu.edu/humannutrition/omega3.htm)
was updated.
|
Debra Palmer Keenan Department of Nutritional
Sciences |
Tel: (732)932-9853 Fax: (732) 932-6522 |
. An open ended, qualitative survey prototype
was developed to collect preliminary information on what Registered Dieticians
(RDs) know about omega-3 fatty acids, what they believe their clients know,
what they teach their clients, and what kind of educational opportunities would
be most useful to them to learn more. A convenience sample of ten RDs in
|
Department of Nutrition |
Tel:
(865)974-6260 Fax:
(865)974-3491 |
OBJECTIVES:
Studies are evaluating the effect of different n-3
fatty acids, both form (source) and amount, on tissue functions and correlating
these effects with changes in putative biomarkers relevant to health promotion
and disease prevention. Experimental diets used in animal studies will examine
dietary levels of n-3 PUFA that are achievable in human diets, based on human
equivalent amounts (allometric scaling) in rodent models. We are currently
establishing a mathematical models predicting allometric scaling for dietary
polyunsaturated fatty acids between rodent models and humans and testing this
mathematical model using C57BL/J6 mice.
Following
adjustment and validation of the mathematical model, a series of experiments
will be performed in the same murine model where we will be comparing dietary
alpha-linolenic acid (
|
Jennifer E.L. Anderson, PhD, RD Department of |
Tel: (970)491-7622 Fax: (970) 491-7252 |
During this past year the NC
1167 partners from