الفهرس 
Egg incubation and groupingOnly 14 pages are availabe for public view
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Abstract
Additives are found in many types of food and we often consume them
unknowingly. Thus, it is very important to study the biological consequences
of using food coloring agents. For the time being, people are becoming more
aware of the possible danger of these additives that have no nutritional value.
Taking into account the concentration indicated as the equivalent ADI for
human. The present study showed the toxic effect of some synthetic coloring
agent during organogenesis phase of chick embryonic development due to
single dose in the 6th day of incubation and the ameliorative role of Cur as
natural coloring agent had against this toxicity. The target organs under
investigation were liver, kidney and endoskeleton of embryos. Based on that,
five integrated approaches, namely, morphologoical, skeletal, histological,
immuno-histochemical and molecular were utilized.
1- Morphological and morphometric investigation: this included body,
liver and kidney weights as well as crown-rump length and mortality
rate of chick embryos. In addition, the external feature of embryos. The
investigation displayed that administration of Cur as natural color
decrease in mortality rate and normal growth parameter. But,
administration of both SY and TZ as synthetic color led to increase in
mortality rate, reduction in growth parameter including crown-rump
length, body weight but increase in liver and kidney weights. There was
a high frequency in malformation of skin, head, trunk and limbs of
embryos of both SY and Tz groups. Meanwhile, embryos injected with
both Cur and SY or Tz groups showed salient improvement in terms of
mortality rate, shape, length and weights of both body and organs of
embryos.
2- Skeletal investigation: this included examining the double stained
endo-skeleton system of 20-day-old chick embryos of all groups. No
malformation of bone in natural color groups was observed. On the other hand, several malformations as excencephaly, clindoctyle and
flexed toes as well as sharp lack of ossification and reduction in the
length of ossified pats of long bone were seen in embryos injected with
SY and Tz in 6th day of incubation. Furthermore, administration of Cur
after SY and Tz resulted in an evident decrease in skeletal
malformation compared to SY and Tz groups.
3- Histological investigation: this involved the histological structure of
the liver and kidney of chick embryos of different groups. The liver of
Cur groups displayed normal histological structure. On the other hand
liver of SY and Tz treated groups showed massive change throughout
the lobule with cellular vacuolization, leucocytic infiltration, dilatation
in central vein with haemorrhagic conditions, fibrosis and hyalinization
of hepatocyte especially in SY groups. Also, microgranuloma in
hepatocyte of Tz groups was observed. The liver of combined groups
showed an evident ameliorative result. Otherwise, the kidney of Cur
groups displayed no pathological effect. But, kidney of SY and Tz
injected groups revealed dilatation in convoluted renal tubules and the
lining epithelium showed degenerative changes, oedema especially in
SY groups and hyalinization of tubules with presence of fibrosis, as
well as hypertrophy of renal glomeruli showed in Tz groups. In the
kidney of combined SY, Tz and Cur, despite the presence of mild
tubular degeneration and epithelial vacuolization in renal tubules,
glomeruli maintained better morphology compared with SY and Tz
groups.
4- Immuno-histochemical investigation: this involved investigation of
the pattern of expression of proapoptotic marker Caspase-3 in the liver
and kidney of embryos of different groups. The Cur treated groups
showed decrease in expression of Caspase-3 of both liver and kidney
cells but, SY and Tz treated embryos showed increase in the expression of Caspase-3. While, co-adminestration of Cur resulted in decreased
expression in Caspase-3in the liver and kidney of both groups.
5- Molecular investigation: this involved two parts:
A- Determination of DNA fragmentation by gel electrophoresis: the
cells of Cur treated group showed no damage in DNA. On the other
hand, the cells of both SY and Tz injected group revealed extensive
DNA fragmentation compared with control. The cells taken from
combined groups displayed some DNA fragmentation but less than SY
and Tz groups.
B- Detection of DNA damage and measurement of cell cycle
distribution: this has been done using flow cytometry and applied on
liver and kidney of coloring agent. In accordance with the mentioned
present investigation, low percentage of DNA damage and normal
trend of cell cycle in Cur group. While, treated groups with SY and Tz
showed high percentage in DNA damage in the cells and arrested S
phase of cell cycle. The combined groups with Cur revealed
amelioration effect in percentage of DNA damage and in the cell cycle
trend of both groups.