2SCIEN0CE NEWS OF THE YEAR | Body & Brain
The sleep, diabetes link
pancreatic cells have melatonin receptor
scientists find a surprisingly clear connection between
sleep and a healthy body: the regulation of sugar levels in
three large genomic studies, all online december 7 in
Nature Genetics, describe the first genetic link between
sleep and type 2 diabetes, a disease marked by high
blood sugar levels (SN: 1/3/09, p. 5). the research places
bodily rhythms, including the clock that sets human sleep
cycles, squarely in the blood sugar business.
melatonin is a major regulator of the body’s sleep
clock, best known for its sleep-inducing properties.
people with a single-letter change in the gene encoding
a molecule that senses melatonin are more likely to
develop diabetes, the studies show. one of the stud-
ies also showed that the sensing molecule, known to
be expressed in the brain, also sits on the outside of
insulin-producing pancreatic cells.
the results identify the melatonin system as a
“fascinating new target” for diabetes treatments, says
endocrinologist leif groop of lund university in malmö,
sweden, who coauthored two of the new reports. these
data link two trends in the united states —rising diabe-
tes rates and falling sleep levels.
Blind may see Gene therapy
restores limited vision in
three people with an inherited form of blindness. Studies in mice indicate that
other cells in the retina can
take over for rod and cone
cells (SN: 5/24/08, p. 8).
Early signal Before symptoms appear, inflammation-promoting genes become
active in immune cells in the
brains of people at risk of
developing bipolar disorder
(SN: 4/12/08, p. 228).
HIV updates Early HIV treatment can increase a patient’s
survival chances (SN Online:
10/27/08). A new drug
(chemical structure shown)
can, with other therapies,
suppress the most drug-resis-tant strains of the virus (SN
Online: 7/23/08). And clinics
in Africa experience long lines
for discounted or free male
circumcision as word spreads
that the operation provides
partial protection against HIV
(SN: 1/3/09, p. 14).
Scary malaria The parasite that causes malaria is
showing signs of thwarting top-line drugs called
artemisinins (SN: 11/22/08,
p. 9). But new reports show
evidence that a vaccine still
in the testing stage halves a
child’s risk of getting malaria
(SN: 1/3/09, p. 15).
Same brain map Months
after receiving a right-hand
transplant, a man displays
a partial sense of touch in
the new hand, activating the
same brain areas that would
have controlled his original
hand (SN: 11/8/08, p. 18).
A-beta on the brain Coma-
tose patients make more
amyloid-beta — a substance
that forms characteris-
tic plaques in the brains of
Alzheimer’s patients — as the
patients’ brains heal from
injury (SN Online: 8/28/08).
Dopamine and zzzz’s The
brain chemical dopamine
builds up in some parts of the
brain when sleep is lost (SN:
9/13/08, p. 11). Dopamine also
aids in learning and memory,
but too much of the chemical
can hinder performance (SN:
8/30/08, p. 8).
New neuron insights Newborn neurons (green, above)
help mice build memories.
Other research shows that
antidepressants may help
trigger neuron generation
in the hippocampus ( SN:
9/27/08, p. 5).
Glass a day Cell tests suggest that resveratrol, the
substance that seems to
account for the healthful effects of red wine, may
have antiobesity effects
(SN Online: 6/16/08). Other
research muddies the idea
that resveratrol can mimic
the life-extending effects of
a calorie-restricted diet, suggesting that the compound
improves health but doesn’t
necessarily lengthen life in
humans. And it also may
indirectly harm the brain
(SN: 8/2/08, p. 14).
clockwise from top left, Body & Brain: chunmei zhao/gage laB/
salk institute; cathrine wessel/corBis; damien persohn
Statin ups and downs Older
people taking cholesterol-
lowering statin drugs seem
less likely to develop demen-
tia (SN Online: 7/28/08).
A variant form of the gene