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[A1CR]

http://en.wikipedia.org/wiki/Hemolymph and the storage protein
http://en.wikipedia.org/wiki/Vitellogenin in grasshoppers
had been
previously studied for the effect that starvation has on
vitellogenin, which
is important for reproduction, and could thus be a marker
for the modulation
of the reproduction/survival switch that occurs with CR in
the (1) paper.
Both proteins were greatly reduced by starvation. More
recently, life span
and the level of storage protein, which may be more subject
to be CR than
essential proteins, in the grasshopper
http://en.wikipedia.org/wiki/Hemolymph#Open_circulatory_system
was examined
for the effect of CR. Life spans were increased at moderate
CR levels, and
hemolymph levels were unaffected. Thus, discrimination
between starvation
and CR may be evidenced. The two papers appear to be the
first data on
grasshopper CR, and the grasshoppers had apparently 60% or
more longer lives
than those that were fed ad libitum.

1. Fei H, Martin TR, Jaskowiak KM, Hatle JD, Whitman DW,
Borst DW.
Starvation affects vitellogenin production but not
vitellogenin mRNA levels
in the lubber grasshopper, Romalea microptera.
J Insect Physiol. 2005 Apr;51(4):435-43.
PMID: 15890187

The interaction of juvenile hormone (JH) and nutrition was
studied during
the oviposition cycle of the Eastern Lubber grasshopper
(Romalea
microptera). Starvation of females early or in the middle of
the cycle
inhibited oocyte growth. Starvation for 4 days also reduced
hemolymph levels
of JH III and vitellogenesis (Vg) to 25% and 15%,
respectively, of the
levels in fed animals. Likewise, Vg production by fat body
fragments
incubated in vitro was reduced to 2% of the levels in fed
animals and total
protein synthesis was reduced to 25%, suggesting that
starvation had a
stronger effect on Vg synthesis than on protein synthesis.
These effects
were reversed when starved animals were fed again. However,
fat body levels
of Vg-mRNA were similar in fed and starved animals,
indicating that
starvation did not affect transcript levels. We tested
whether the decline
in JH levels mediated the other starvation effects by
infusing animals with
JH III or vehicle for 2 days at the onset of starvation.
Infusion of JH
elevated JH and Vg-mRNA levels 670% and 103%, respectively,
above the levels
in vehicle-infused animals. However, Vg production and
hemolymph levels of
Vg were similar to the levels in vehicle-infused animals.
These data suggest
that JH alone is insufficient to stimulate Vg production.

2. Hatle JD, Wells SM, Fuller LE, Allen IC, Gordy LJ,
Melnyk S, Quattrochi
J.
Calorie restriction and late-onset calorie restriction
extend lifespan but
do not alter protein storage in female grasshoppers.
Mech Ageing Dev. 2006 Oct 16; [Epub ahead of print]
PMID: 17049582

Calorie restriction (CR) and late-onset CR enhance longevity
in many
organisms. Resource allocation theory suggests that
longevity is enhanced by
increasing somatic storage, at the expense of current
reproduction.
Phytophagous insects accumulate amino acids as hemolymph
storage proteins
for major developmental events. We hypothesized that protein
storage is
involved in life extension from CR. In a longitudinal
experiment, we tested
whether CR altered protein storage in female grasshoppers.
Individuals on CR
(60 or 70% of ad libitum) or late-onset CR had at least 60%
greater
longevity than ad libitum individuals. Age at first
oviposition, dry mass of
the first clutch, or lifetime fecundity were not affected by
CR, but CR did
increase the number of clutches produced. Most important,
females on
life-extending CR and late-onset CR did not differ in the
concentration of
hemolymph storage of proteins in comparison to ad libitum
females. Protein
storage changed with time in all groups, demonstrating
sufficient
sensitivity in our methods. Previous experiments have shown
that severe CR
( approximately 30% of ad libitum) can reduce hemolymph
storage. Therefore,
the reduction in intake needed to extend lifespan is not
sufficient to
reduce protein storage in the hemolymph. These results do
not support the
hypothesis that protein storage is involved in life
extension from CR.