Estrogen‐mediated coupling via gap junctions in the suprachiasmatic nucleus
European Journal of Neuroscience,
Год журнала:
2024,
Номер
unknown
Опубликована: Фев. 7, 2024
Abstract
The
circadian
clock
orchestrates
many
physiological
and
behavioural
rhythms
in
mammals
with
24‐h
periodicity,
through
a
hierarchical
organisation,
the
central
located
suprachiasmatic
nucleus
(SCN)
hypothalamus.
circuits
of
SCN
generate
precision,
relying
on
intrinsic
coupling
mechanisms,
for
example,
neurotransmitters
like
arginine
vasopressin
(AVP),
vasoactive
intestinal
peptide
(VIP),
neuronal
gamma‐aminobutyric
acid
(GABA)
signalling
astrocytes
connected
by
gap
junctions
composed
connexins
(Cx).
In
female
rodents,
presence
estrogen
receptors
(ERs)
dorsal
suggests
an
influence
(E2)
circuit
timekeeping
that
could
regulate
rhythm
coupling.
To
investigate
this,
we
used
explants
together
hypothalamic
neurons
astrocytes.
First,
showed
E2
stabilised
amplitude
when
rAVPs
(receptor‐associated
peptides)
were
inhibited.
However,
phase
delay
induced
VIPAC2
(VIP
receptors)
inhibition
remained
unaffected
E2.
We
then
exerted
its
effects
via
ERβ
(estrogen
receptor
beta),
resulting
increased
expression
Cx36
Cx43
.
Notably,
specific
both
resulted
significant
reduction
within
SCN.
Remarkably,
restored
period
inhibited
but
not
inhibition.
This
implies
network
between
neurons,
responsible
SCN,
can
be
reinforced
conclusion,
these
findings
provide
new
insights
into
how
regulates
ex
vivo
ERβ‐dependent
manner,
underscoring
crucial
role
fortifying
SCN's
rhythm.
Язык: Английский
Understanding the mechanistic interlink between circadian misalignment and heart disease in night shift workers: Therapeutic role of behavioral interventions
Sleep And Breathing,
Год журнала:
2025,
Номер
29(1)
Опубликована: Фев. 18, 2025
Язык: Английский
Selective changes in vasopressin neurons and astrocytes in the suprachiasmatic nucleus of Prader–Willi syndrome subjects
Journal of Neuroendocrinology,
Год журнала:
2025,
Номер
unknown
Опубликована: Март 8, 2025
The
hypothalamic
suprachiasmatic
nucleus
(SCN)
hosts
the
central
circadian
pacemaker
and
regulates
daily
rhythms
in
physiology
behavior.
SCN
is
composed
of
peptidergic
neuron
populations
expressing
arginine
vasopressin
(AVP)
vasoactive
intestinal
polypeptide
(VIP),
as
well
glial
cells.
Patients
with
Prader-Willi
Syndrome
(PWS)
commonly
experience
disturbances,
which
are
particularly
evident
their
sleep/wake
patterns.
Using
publicly
available
single-cell
RNA
sequencing
data,
we
assessed
cell-type
specificity
PWS-causative
genes
murine
SCN,
revealed
differential
presence
PWS-related
neural
subpopulations.
We
then
investigated
neurons
cells
using
immunohistochemistry
postmortem
hypothalami
PWS
subjects
matched
controls.
profiled
characterized
by
AVP
VIP,
astroglia
fibrillary
acid
protein
(GFAP),
microglia
marked
ionized
calcium-binding
adapter
molecule
1
(Iba1)
NADPH
oxidase
2
(NOX2).
Our
analysis
an
increased
total
number,
neuronal
density,
relative
staining
intensity
AVP-containing
compared
to
controls
while
VIP-containing
were
unaltered.
In
contrast,
GFAP-expressing
astroglial
significantly
lower
subjects.
Moreover,
did
not
detect
any
differences
between
Collectively,
our
findings
show
that
selectively
affects
astrocytes
SCN.
As
each
these
cell
can
affect
rhythmicity
biological
clock
machinery,
disruption
may
contribute
disturbances
patients
PWS.
Язык: Английский
Circadian rhythm mechanism in the suprachiasmatic nucleus and its relation to the olfactory system
Frontiers in Neural Circuits,
Год журнала:
2024,
Номер
18
Опубликована: Март 25, 2024
Animals
need
sleep,
and
the
suprachiasmatic
nucleus,
center
of
circadian
rhythm,
plays
an
important
role
in
determining
timing
sleep.
The
main
input
to
nucleus
is
retinohypothalamic
tract,
with
additional
inputs
from
intergeniculate
leaflet
pathway,
serotonergic
afferent
raphe,
other
hypothalamic
regions.
Within
two
major
subtypes
are
vasoactive
intestinal
polypeptide
(VIP)-positive
neurons
arginine-vasopressin
(AVP)-positive
neurons.
VIP
for
light
entrainment
synchronization
neurons,
whereas
AVP
period
determination.
Output
targets
include
hypothalamus
(subparaventricular
zone,
paraventricular
preoptic
area,
medial
hypothalamus),
thalamus
(paraventricular
thalamic
nuclei),
lateral
septum.
also
sends
information
through
several
brain
regions
pineal
gland.
olfactory
bulb
thought
be
able
generate
a
rhythm
without
nucleus.
Some
reports
indicate
that
rhythms
cortex
exist
absence
but
another
report
claims
influence
regulation
by
sensory
than
stimuli,
including
olfaction,
has
not
been
well
studied
further
progress
expected.
Язык: Английский
In vivo recording of the circadian calcium rhythm in Prokineticin 2 neurons of the suprachiasmatic nucleus
Scientific Reports,
Год журнала:
2023,
Номер
13(1)
Опубликована: Окт. 9, 2023
Abstract
Prokineticin
2
(Prok2)
is
a
small
protein
expressed
in
subpopulation
of
neurons
the
suprachiasmatic
nucleus
(SCN),
primary
circadian
pacemaker
mammals.
Prok2
has
been
implicated
as
candidate
output
molecule
from
SCN
to
control
multiple
rhythms.
Genetic
manipulation
specific
Prok2-producing
would
be
powerful
approach
understanding
their
function.
Here,
we
report
generation
Prok2-tTA
knock-in
mice
expressing
tetracycline
transactivator
(tTA)
specifically
and
an
application
these
vivo
recording
Ca
2+
rhythms
neurons.
First,
efficient
expression
tTA
was
verified
by
crossing
with
EGFP
reporter
mice.
were
then
used
express
fluorescent
sensor
record
rhythm
vivo.
cells
showed
clear
both
light–dark
constant
dark
conditions,
peaks
around
midday.
Notably,
hours
high
nearly
coincided
rest
period
behavioral
rhythm.
These
observations
fit
well
predicted
function
pathway
suppressing
locomotor
activity
during
daytime
subjective
daytime.
Язык: Английский
The transcription factor VAX1 in VIP neurons of the suprachiasmatic nucleus impacts circadian rhythm generation, depressive-like behavior, and the reproductive axis in a sex-specific manner in mice
Frontiers in Endocrinology,
Год журнала:
2023,
Номер
14
Опубликована: Дек. 22, 2023
Background
The
suprachiasmatic
nucleus
(SCN)
within
the
hypothalamus
is
a
key
brain
structure
required
to
relay
light
information
body
and
synchronize
cell
tissue
level
rhythms
hormone
release.
Specific
subpopulations
of
SCN
neurons,
defined
by
their
peptide
expression,
regulate
output.
Here
we
focus
on
vasoactive
intestinal
(VIP)
expressing
neurons
SCN.
VIP
are
known
circadian
reproductive
function.
Methods
To
specifically
study
generated
novel
knock
out
mouse
line
conditionally
deleting
enriched
transcription
factor,
Ventral
Anterior
Homeobox
1
(Vax1),
in
(Vax1
Vip
;
Vax1
fl/fl
:Vip
Cre
).
Results
We
found
that
females
presented
with
lengthened
estrous
cycles,
reduced
circulating
estrogen,
increased
depressive-like
behavior.
Further,
males
shortened
period
locomotor
activity
ex
vivo
period.
On
molecular
level,
shortening
was
driven,
at
least
partially,
direct
regulatory
role
VAX1
clock
genes
Bmal1
Per2
.
Interestingly,
expression
arginine
vasopressin
(
Avp
)
paraventricular
nucleus,
which
resulted
corticosterone.
AVP
gonadotropin-releasing
(GnRH)
kisspeptin
neurons.
determine
how
neuroendocrine
network
impacted
mice,
assessed
GnRH
sensitivity
challenge
females,
but
not
males,
had
an
kisspeptin,
leading
luteinizing
showed
small,
significant
increase
total
sperm
modest
delay
pubertal
onset.
Both
male
female
mice
were
fertile
litters
comparable
size
frequency
controls.
Conclusion
Together,
these
data
identify
as
neurological
overlap
between
timekeeping,
reproduction,
symptoms
provide
insight
into
Язык: Английский
Arginine vasopressin: Critical regulator of circadian homeostasis
Peptides,
Год журнала:
2024,
Номер
177, С. 171229 - 171229
Опубликована: Апрель 23, 2024
Язык: Английский
The Functional Connectome Mediating Circadian Synchrony in the Suprachiasmatic Nucleus
bioRxiv (Cold Spring Harbor Laboratory),
Год журнала:
2024,
Номер
unknown
Опубликована: Дек. 11, 2024
Abstract
Circadian
rhythms
in
mammals
arise
from
the
spatiotemporal
synchronization
of
∼20,000
neuronal
clocks
Suprachiasmatic
Nucleus
(SCN).
While
anatomical,
molecular,
and
genetic
approaches
have
revealed
diverse
cell
types
signaling
mechanisms,
network
wiring
that
enables
SCN
cells
to
communicate
synchronize
remains
unclear.
To
overcome
challenges
revealing
functional
connectivity
fixed
tissue,
we
developed
MITE
(Mutual
Information
&
Transfer
Entropy),
an
information
theory
approach
infers
directed
cell-cell
connections
with
high
fidelity.
By
analyzing
3447
hours
continuously
recorded
clock
gene
expression
9011
17
mice,
found
connectome
was
highly
conserved
bilaterally
across
sparse,
organized
into
a
dorsomedial
ventrolateral
module.
most
were
local,
discovered
long-range
ventral
both
dorsal
SCN.
Based
on
their
connectivity,
can
be
characterized
as
circadian
signal
generators,
broadcasters,
sinks,
or
bridges.
For
example,
subset
VIP
neurons
acts
hubs
generate
signals
critical
daily
neural
network.
Simulations
experimentally
inferred
networks
recapitulated
stereotypical
dorsal-to-ventral
wave
PER2
ability
spontaneously
synchronize,
emergent
dynamics
are
sculpted
by
connectivity.
We
conclude
provides
powerful
method
infer
connectomes,
architecture
mediates
synchrony
space
time
mammalian
Highlights
MITE,
method,
accurately
among
cells.
patterns
spatially
organize
two
regions
function
bridges
information.
One-third
serve
drive
Key
features
mediate
generation
maintenance
intercellular
waves
Язык: Английский