7. Brain maturation is a process where the structure and performance of the brain
is modified. In needs:
myelination
muscle tonicity
cell differentiation
environmental stimulation
It all is related with the development of cognitive
functions
8. Arain, M (2013) Maturation of the adolescent brain Neuropsychiatr Dis Treat; 9: 449–
461.
9. Arain, M. (2013) Maturation of the adolescent brain Neuropsychiatr Dis Treat; 9: 449–461.
10. Paus, T. (2005) Mapping brain maturation and cognitive development
during adolescence. TRENDS in Cognitive Sciences Vol.9 No.2
11. Maternal stress
any physical or psychological stress of the mother
neuropsychiatric disorders
increase of the ACTH levels
the stimulation of adrenal gland
Adrenal hormones causes:
rise of glycemia
reduction of inflammatory and immune response
alters hydrolytic balance
12. Early life stressors
The stress response
On mood and cognition
in adulthood
Produces
Have effects
13. Chronic exposure to glucocorticoids contribute
to the dysfunction of the inhibitory network
and impairment of rhythmic oscillations
Are critical for the regulation of
brain activity and complex
cognitive processes
14. Thus,
A dysfunctional GABAergic system is
associated with the pathogenesis of
neuropsychiatric diseases such as
schizophrenia, anxiety and depression
15. GABA is a neurotransmitter, used:
the principal inhibitory of the CNS
reduction of neuronal excitability
regulation of muscle tone
➔The relations of these terms show the different effects of the maternal stress
in the maturation of the brain. The elevated amounts of adrenal hormones are
related to the dysfunctional brain maturation, such as the gaba receptors..
16. GABA transmission plays
important roles
neuronal
migration
neurite outgrowthcell proliferation
generating
synchronized
network activity
17. Cation Chloride
Cotransporter (CCC)
Is the key controlling the
GABAA receptor function
control the reversal
potential of the GABAA
receptor-mediated current
(EGABA)
which is important for the
modulation of the GABAA
receptor function
19. E. Delpire. Cation-Chloride Cotransporters in Neuronal Communication.
Physiology 2000 Vol. 15 no. 6, 309-312
20. E. Delpire. Cation-Chloride Cotransporters in Neuronal
Communication. Physiology 2000 Vol. 15 no. 6, 309-312
21. GABAa receptor
Alfa 1 Alfa 5
is required for the
tonic inhibitory
function of GABA
is required for the
phasic inhibition
function of GABA
indicates the
maturation of the
GABAA receptor
function
22. Chronic exposure to glucocorticoids contribute
to the dysfunction of the inhibitory network
and impairment of rhythmic oscillations
Are critical for the regulation of
brain activity and complex
cognitive processes
23. Vitale G,Salvioli S franceschi, C. Nature
Reviews Endocrinology 9, 228-240 (April
2013) oi:10.1038/nrendo.2013.29
24. Early life stress exerts an effect on the
hippocampal neurons and predisposes
individuals to neuropsychiatric diseases
Vitale G,Salvioli S franceschi, C. Nature
Reviews Endocrinology 9, 228-240
Mania
psicosis
schizophrenia
25. Introduction
Neuropsychiatric illness Brain disfunction
Mania = fast mood change
Psicosis = reality loss
Schizophrenia = loss of reality perception or alteration of the reality
26. “In this study we hypothesized that prenatal stress may
affect the structural and functional maturation of the
GABAA receptor in the hippocampus of rat pups”
27. Examine the effect of maternal restraint stress on
the levels of NKCC1 and KCC2, as well as GABAA
receptors a1 and a5 subunits in the hippocampus
Objective of experiment
29. Sprague
Dawley
Temperatura y humedad
controlada (?)
12 h luz/oscuridad ciclos
Acceso libre a agua y
alimento
y sus crías
Cada fue pesada
en el día
gestacional(GD) 7–21
En la mañana del GD
21, cada rata
embarazada recibió
material de anidación
Revisadas dos veces al
día para la aparición de
una camada de crías
33. El día que se descubre una camada, se
denomina “día posnatal o (Po)”
“Gestation days 14–20 were selected because they represent the
most sensitive period for the behavioral teratogenic effect of
prenatal stress”
34. Preparaciòn del tejido
Los tejidos del hipocampo fueron recolectados
de las crías y suspendidos en un buffer a
diferentes días postnatales (P)
desde P7, P14, P21, P28 hasta
P40, con n = 4/grupo
38. WESTERN BLOT
“Usado en investigación para separar e identificar proteínas. En esta técnica,
las proteínas se separan según peso molecular, y por ende por tipo, a través de
gel de electroforesis. Los resultados son transferidos posteriormente a una
membrana, produciendo bandas para cada proteína. La membrana es luego
incubada con anticuerpos específicos para la proteína de interés.”
PubMed Central® (PMC)
44. Maternal restraint stress alters NKCC1 and KCC2 in the
hippocampus of rat pups at puberty
They examined the effects of maternal restraint stress, during the
gestation day (GD) 14–20, on the levels of NKCC1 and KCC2 in the
hippocampus of rat pups and compared between the groups at
different postnatal ages.
45. Maternal restraint stress alters NKCC1 and KCC2 in the
hippocampus of rat pups at puberty
Maternal restraint stress caused a
transient but significant increase in
the level of NKCC1 in the
hippocampus at P14 (but no
significant difference when
observed at the other periods)
Maternal restraint stress caused a
transient but significant increase in
the KCC2 level in the
hippocampus of rat pups during
the weaning period (P21) and this
was followed by a decrease
during the preadolescence
period (P28)
46. Fig. 1.
Effects of maternal restraint stress on the level of NKCC1 in the hippocampus of rat pups. The (Upper) western blot
analysis of NKCC1 in the hippocampal tissue comparing the prenatal stress groups and the control groups during P7–P40.
The (Lower) bar graph displays the results from western blot analysis. Data were expressed as band densities/β-actin ratio;
values represent Mean ± SEM, N = 4. There was a significant difference when compared with control group at *p < 0.05.
47. Fig. 2.
Effects of maternal restraint stress on the levels of KCC2 in the hippocampus of rat pups. The (Upper) western blot analysis of
KCC2 in the hippocampal tissue comparing the prenatal stress groups and control groups during P7–P40. The (Lower) bar
graph displays the results from the western blot analysis. Data were expressed as band densities/β-actin ratio; values
represent Mean ± SEM, N = 4. There was a significant difference when compared with the control group at **p < 0.01 and *p <
0.05.
48. Maternal restraint stress delays development of the GABAA receptor
α1 and α5 subunits in the hippocampus of rat pups
In the control pups, the developmental expressions of GABAA receptor
α5 and α1 subunits in the hippocampus appear in the opposite way.
Maternal restraint stress
caused a decrease in the
level of the GABAA receptor
α5 subunit at P14 and
followed by an increase at
P21, P28 and P40
maternal restraint stress
caused an increase in the
level of the GABAA α1
subunit at P14 followed by
a significant decrease at
P21 and P28
49. Fig. 4.
Effects of maternal restraint stress on the levels of the GABAA receptor α5 subunit in the hippocampus of rat pups. The (Upper)
western blot analysis of GABAA receptor α5 subunit in the hippocampal tissue comparing the prenatal stress and control groups during
P7–P40. The (Lower) bar graph displays the results from the western blot analysis. Data were expressed as a band densities/β-actin
ratio; values represent Mean ± SEM, N = 4. There was a significant difference when compared with the control group at **p < 0.01 and
*p < 0.05.
50. Fig. 5.
Effects of maternal restraint stress on the levels of the GABAA receptor α1 subunit in the hippocampus of rat pups. The (Upper) western blot
analysis of the GABAA receptor α1 subunit in the hippocampal tissue comparing the prenatal stress and control groups during P7–P40. The
(Lower) bar graph displays the results from the western blot analysis. Data were expressed as band densities/β-actin ratio; values represent
Mean ± SEM, N = 3. There was a significant difference when compared with the control group at **p < 0.01 and *p < 0.05.
51.
52.
53. Discussion
Author Theory or affirmation Observation (Yes or no)
Rivera & et al, 1999; Emri & et al,
2001; Gulyas & et al, 2001; Stein
& et al, 2004
“while the hyperpolarizing GABA
is completed by the second
postnatal week due to the
progressive reduction of NKCC1
activity in parallel with the
enhanced activity of KCC2”
No
Sarkar & et al, 2011 “In contrast, prenatal stress
causes a significant decrease in
the KCC2 level and its activity in
the hippocampus”
No
54. Discussion
Author Theory or affirmation Observation (Yes or no)
(Rivera and et al, 1999 and Clayton and
et al, 1998)
KCC2 expression significantly increases
during the second postnatal week,
which is the co-incidence time point
when the developmental switch of
GABAA receptor activity is observed
YES
Lu et al., 1999 and continually increased until P28 YES
55. Discussion
Author Theory or affirmation Observation (Yes or no)
Prenatal stress delays the
developmental shift of the
GABAA receptor α1 and α5
subunits that normally occur
around P21 in the control pups.
Ramos and et al, 2004 and Laurie et al.,
1992
NO
56. Conclusions
The study could prove that maternal stress decrease the
expression level of some important proteins associated
with many psychological dysfunctions.
Some relevant aspects were not measured to establish
the importance of the variations on the different
proteins. They mentioned a factor, the BDNF. It is
totally important of the KCC2 expression promotion
and in the study it had not been measured.
57. Conclusions
It's clearly important the discovery about how the variations of both KCC2 and
NKCC1 cotransporters alters the expression of GABAa receptors but we think
that it's most important to continue researching in the exact mechanism how
the prenatal stress alters this cotransporters because with that information,
we could start developing alternatives to prevent neuropsychiatric diseases
caused by prenatal stress in a future.
The article talks about some things that they discovered but neither in the
results nor in the discussion are exposed and we think that they are important
facts in the research, but with no evidence, it's hard to trust in them.
The assay is based on the observation that the absorbance maximum for an acidic solution of Coomassie Brilliant Blue G-250 shifts from 465 nm to 595 nm when binding to protein occurs.
ANTICUERPOS USADOS
Weaning is the process of gradually introducing a mammal infant to what will be its adult diet and withdrawing the supply of its mother's milk.
