Newsletter 02 2006.pdf - Sight and Life

SIGHT AND LIFE 22
NEWSLETTER 2/2006
Maria Stacewicz-Sapuntzakis receives award from Wendy White.
in North American whites, as
compared to peers in Shanghai,
China. The Physicians’ Health
Study implicated higher intakes
of tomato sauce, tomatoes, pizza
and strawberries, all sources of
lycopene (a non-provitamin A
carotenoid), with reduced prostate
cancer occurrence. Prof.
Erdman summarized the science
findings of his group in pursuing
the bases of these epidemiological
observations. Using a prostatic
cancer murine tumor model,
the combination of broccoli and
tomato proved to be superior
to tomato alone, and both were
superior to isolated lycopene in
terms of anti-cancer activity in the
mouse tumors. The conclusion
is that lycopene is not the only
preventive substance in broccoli
or tomatoes.
At the VARIG/CARIG social event.
The other basic pursuit involved
the potential bioactivity of metabolic
derivatives of lycopene.
Analogous to the format by which
retinoids and apo-carotenals
of different carbon lengths are
produced by central or eccentric
cleavage of provitamin A carotenes,
the search has been joined
for generation of apo-lycopenals.
The carotene monoxygenase I
(CMO I), responsible for central
cleavage of β-carotene (formerly
known as 15,15’ monoxygenase)
is inactive in cleaving lycopene.
However, the carotene monoxygenase
II (CMO II), which produces
eccentric cleavage of β-carotene,
can also generate apo-lycopenals
in in-vitro systems. These products
have recently been detected
with sensitive assay techniques
in human plasma and breast milk
in concentrations over 100 times
lower than that of lycopene itself.
Studies documenting the bioactivity
of lycopene split-products have
yet to appear, but the fundamentals
of carotene biology for retinoids
are a template for inquiry into
potential anti-cancer mechanisms
for lycopene.
The final wisdom from Prof.
Erdman is not to ignore other
compounds, even phytoene and
phytofluene precursors. In the
ripe tomato, the sum of these
two compounds is equivalent by
weight to that of lycopene, and
these non-aromatic forms are 10
times more abundant than alphaand
beta-carotenes combined.
Heather Mernitz in front of her
awarded poster.
Other awards were involved in
the CARIG meeting arena in San
Francisco. These included travelawards
based on the scientific
merit of the abstracts submitted
by graduate students for presentation
in Experimental Biology
on carotenoids. The winner was
Francesca Alvarez-Calderon,
from Florida International University,
for her free-paper entitled: A
computational study of end-group
conformational barriers in carotenoids.
In addition, a new element
was brought in for the benefit of
encouraging and recognizing the
talent of young trainees this year.
This was a poster competition as
part of the VARIG/CARIG social,
held following the Conference. A
total of 12 contestants exhibited
their free-paper posters, brought
for display in the mini-symposia
of the EB 2006. Heather Mernitz,
from the USDA Human Nutrition
Research Center at Tufts University
was judged as best in the
competition with her poster on
Inhibition of lung carcinogenesis
by 9-cis retinoic acid and 1,25
dihydroxyvitamin D3 in the A/J
mouse model. Finally, the Steering
Committee of CARIG made
a “surprise award”, in the form
of a recognition-of-merit plaque,
to Maria Stacewicz-Sapuntzakis,
the tireless and undaunted editor
of the CARIG Newsletter, who
has undertaken its semi-annual
publication since the founding of
the Group.