This study analyzed glycogen storage and localization of glycogen metabolizing enzymes in the murine uterus from proestrus until implantation. Immunohistochemistry and western blot techniques were used to identify and locate key glycogen synthesizing enzymes in the glandular epithelium, luminal epithelium, and stroma. The results showed glycogen deposits and enzyme expression patterns in the different uterine tissues across the estrous cycle and implantation. The discussion agrees with previous studies that glucose levels must be carefully regulated for embryo development, and that glycogen may act as an energy reserve for preimplanted embryos.

1. Presented by:
Juan José González Arias
Medical School 3rd Semester
Universidad Pontificia Bolivariana
2022

2. Introduction:
■ Before implantation, embryos are dependent on nutrients secreted into the
uterine lumen. Of the nutrients in uterine secretions, glucose is one of the
most important. The uterus lacks the enzymes to make glucose de novo;
therefore, all glucose used by the endometrium or secreted into the uterine
lumen must come from maternal circulation. The uterus may take up glucose
from maternal circulation as needed whit GLUTS; however, the endometrium
can also transiently store glucose as the macromolecule glycogen.

3. Introduction:
■ but it is not clear which tissues store the glycogen or where enzymes that
metabolize glycogen are expressed. in this investigation sought to characterize
the glycogen deposits in the murine uterus from proestrus to implantation in
the glandular epithelium, luminal epithelium and stroma, locate key glycogen
metabolize enzymes during the same period and determine if decidualization is
sufficient to drive glycogen accumulation in the endometrial stroma regardless
of pregnancy.

4. Objetives:
This study analyzed glycogen storage and
localization of glycogen metabolizing
enzymes from proestrus until
implantation in the murine uterus.

5. Methods
4.3 Immunohistochemistry
Immunohistochemistry is a procedure that aims to make a
specific target visible, which is usually a protein. This
technique makes it possible to identify the location of a
specific substance at the tissue or cellular level and is
mainly based on the use of tests that specifically bind to a
substance to be identified. In this study, this method is used
to identify and locate the main enzymes that synthesize
glycogen. A control was established in which all the steps of
the immunohistochemistry performed for all proteins were
performed except that the main one was replaced with an
isotype control (anti-green fluorescent protein).
4.4 | Western blots
Is an analytical technique used in cell and molecular
biology to identify specific proteins in a complex mixture of
proteins, such as that present in cell or tissue extracts. The
technique uses three steps to achieve this: size separation,
transfer to a solid support, and finally visualization by
labeling proteins with the use of appropriate primary or
secondary antibodies. In this investigation they were used
to visualize and repair the proteins present in the
myometrium and in the endometrium in pregnancy and in
this way study the results and compare them.

6. Methods
4.1 Animals
CD-1 mice from Charles River Laboratories were used and
maintained at the University of Illinois animal facility. Mice were
maintained on a 12L:12D light cycle and fed a standard chow
diet. To obtain proestrus uteri, vaginal lavages were examined
daily to monitor the estrous cycle in mice. After at least two
normal estrous cycles, mice were sacrificed in proestrus and the
uterine horns were harvested. To induce artificial decidualization
of the uterus, female CD-1 mice were ovariectomized. The right
uterine horn was left unstimulated and served as an internal
control. . Mice were treated with 1 mg progesterone in 0.1 mL
corn oil daily for 4 days and sacrificed 96 h after inducing
decidualization.
4.2 PAS staining
The basis of the reaction consists in oxidizing the tissues by
means of periodic acid to increase the number of carbonyl
groups (aldehydes or ketones) present in them.
Subsequently, the sample is treated with Schiff's reagent
that reacts with two adjacent aldehyde groups giving rise to
a characteristic red-purple color. They were analyzed with
this stain o (the glandular epithelium, the luminal
epithelium and the stroma)

7. Results
■ Figura 1
■ Figura 2

8. Results
■ Figura 6
■ Figura 9
Figura 8

9. discusion
autor Que dijo Esta de acuerdo o no con el
articulo
Cagnone et al.,2012;
Pantaleón et al.,2010
Demasiada glucosa durante el
desarrollo de la división es
tóxica para el embrión

Gardner & Leese, 1990; Leese
y Barton, (1984)
El embrión temprano prefiere
el piruvato y el lactato como
sustratos energéticos, pero ha
cambiado a la glucosa en la
etapa de blastocisto

Dean, (2019) Esto ha llevado a la teoría de
que el glucógeno actúa como
un reservorio de energía para
los embriones preimplantados


10. conclutions
■ b

11. Mapa conceptual