10 research outputs found
Building sustainable neuroscience capacity in Africa : the role of non-profit organisations
While advances in neuroscience are helping to improve many aspects of human life, inequalities exist in this field between Africa and more scientifically-advanced continents. Many African countries lack the infrastructure and appropriately-trained scientists for neuroscience education and research. Addressing these challenges would require the development of innovative approaches to help improve scientific competence for neuroscience across the continent. In recent years, science-based non-profit organisations (NPOs) have been supporting the African neuroscience community to build state-of-the-art scientific capacity for sustainable education and research. Some of these contributions have included: the establishment of training courses and workshops to introduce African scientists to powerful-yet-cost-effective experimental model systems; research infrastructural support and assistance to establish research institutes. Other contributions have come in the form of the promotion of scientific networking, public engagement and advocacy for improved neuroscience funding. Here, we discuss the contributions of NPOs to the development of neuroscience in Africa
Vitamin D3 Receptor Activation Rescued Corticostriatal Neural Activity and Improved Motor-Cognitive Function in āD2R Parkinsonian Mice Model
Background: fourth generation antipsychotics have been implicated in the blockade of calcium
signalling through inhibition of dopamine receptive sites on dopaminergic D2 Receptor (D2R). As a
result of the abnormal calcium signalling associated with D2R inhibition, changes occur in the motor
and memory neural axis leading to the observed behavioural deficits after prolonged haloperidol.
Thus, Vitamin D3 receptor (VD3R), a calcium controlling receptor in the striatum can be targeted
to relief the neurological symptoms associated with haloperidol (āD2R) induced PD. Aim:
This study sets to investigate the role of VD3R activation in vitro and in vivo after haloperidolinduced
Dopaminergic (D2R) blockade. In addition, we examined the associated neural activity
and behavioural changes in parkinsonian and VDRA intervention mice. Methods: Dopaminergic
D2R inhibition was investigated in vitro using Melanocytes isolated from the scale of a Tilapia. In
four separate set ups, the cells were cultured in calcium free Ringerās solution as follows; 300 Ī¼M
haloperidol, 100 Ī¼M VD3, 100 mM calcium chloride and a combination of 300 Ī¼M haloperidol
and 100 Ī¼M VD3. Subsequently, dopaminergic vesicle accumulation and calcium signalling were observed in bright field microscopy using blue and green fluorescence probes. In the second phase,
PD was induced in adult BALB/c mice (āD2; n = 8) after 14 days of intraperitoneal haloperidol
treatment (10 mg/Kg). A set of n = 4 mice were untreated (āD2) while the other group (n = 4) received
100 mg/Kg of VD3 for 7 days (āD2/+VDR). The control groups (n = 4 each) were treated with
normal saline (NS) and VD3 (+VDR) for 14 days. At the end of the treatment phase, the animals
were assessed in Rotarod, parallel bar-, cylinder-, Y-Maze-, one trial place recognition- and novel
object recognition-(NOR) tests. Neural activity was measured using chronic electrode implants
placed in the M1 (motor cortex), CPu (striatum), CA1 (hippocampus) and PFC (prefrontal cortex).
Neural activity was compared with the outcomes of behavioural tests for memory and motor functions
and data was expressed as mean Ā± SEM (analysed using ANOVA with Tukey post-hoc test,
significant level was set at 0.05). Results/Discussion: in vitro outcomes show that VDR increase
calcium signalling and reverses the effect of haloperidol; specifically by reducing dopaminergic
vesicle accumulation in the cell body. Similarly, in vivo neural recordings suggest an increase in
calcium hyperpolarization currents in the CPu and PFC of intervention mice (āD2/+VDR) when
compared with the parkinsonian mice (āD2). These animals (āD2/+VDR) also recorded an improvement
in spatial working memory and motor function versus the Parkinsonian mice (āD2).
These outcomes suggest the role of CPu-PFC corticostriatal outputs in the motor-cognitive decline
seen in parkinsonian mice. Similarly, VDRA reduced the neural deficits through restoration of calcium
currents (burst activities) in the intervention mice (āD2/+VDR). Conclusion: VDRA treatment
reduced the motor-cognitive defects observed in haloperidol induced PD. Our findings suggest the
role of VDRA in restoration of calcium currents associated with PFC and CPu corticostriatal outputs
seen as burst frequencies in in vivo neural recording
Vitamin D 3 Receptor Activation Rescued Corticostriatal Neural Activity and Improved Motor Function in āD 2 R Tardive Dyskinesia Mice Model
Haloperidol-induced dyskinesia has been linked to a reduction in dopamine activity characterized
by the inhibition of dopamine receptive sites on D2-receptor (D2R). As a result of D2R inhibition,
calcium-linked neural activity is affected and seen as a decline in motor-cognitive function after
prolonged haloperidol use in the treatment of psychotic disorders. In this study, we have elucidated the relationship between haloperidol-induced tardive dyskinesia and the neural activity in
motor cortex (M1), basal nucleus (CPu), prefrontal cortex (PFC) and hippocampus (CA1). Also, we
explored the role of Vitamin D3 receptor (VD3R) activation as a therapeutic target in improving
motor-cognitive functions in dyskinetic mice. Dyskinesia was induced in adult BALB/c mice after
28 days of haloperidol treatment (10 mg/Kg; intraperitoneal). We established the presence of abnormal involuntary movements (AIMs) in the haloperidol treated mice (āD2) through assessment
of the threshold and amplitude of abnormal involuntary movements (AIMs) for the Limbs (Li) and
Orolingual (Ol) area (Li and Ol AIMs). As a confirmatory test, the dyskinetic mice (āD2) showed
high global AIMs score when compared with the VD3RA intervention group (āD2/+VDR) for Li and Ol AIMs. Furthermore, in the behavioral tests, the dyskinetic mice exhibited a decrease in latency
of fall (LOF; Rotarod-P < 0.05), climbing attempts (Cylinder test; P < 0.05) and latency of Turning
(Parallel bar test; LOT-P < 0.05) when compared with the control. The reduced motor function in
dyskinetic mice was associated with a decline in CPu-CA1 burst frequencies and an increase in
M1-PFC cortical activity. However, after VD3RA intervention (āD2/+VDR), 100 mg/Kg for 7 days,
CPu-CA1 burst activity was restored leading to a decrease in abnormal movement, and an increase
in motor function. Ultimately, we deduced that VD3RA activation reduced the threshold of abnormal movement in haloperidol induced dyskinesia
Vitamin D 3 Receptor Activation Rescued Corticostriatal Neural Activity and Improved Motor - Cognitive Function in ā D 2 R Parkinsonian Mice Model
fourth generation antipsychotics have been implicated in the blockade of calcium
signalling through inhibition of dopamine receptive sites on dopaminergic D
2
Receptor (D
2
R). As a
result of the
abnormal calcium signalling associated with D
2
R inhibition, changes occur in the m
o-
tor and memory neural axis leading to the observed behavioural deficits after prolonged halope
r-
idol. Thus, Vitamin D
3
receptor (VD
3
R), a calcium controlling receptor in the
striatum can be ta
r-
geted to relief the neurological symptoms associated with haloperidol (
ā
D
2
R) induced PD.
Aim:
This study sets to investigate the role of VD3R activation
in vitro
and
in vivo
after haloperidol
-
induced Dopaminergic (D
2
R) blockade. In addi
tion, we examined the associated neural activity
and behavioural changes in parkinsonian and VDRA intervention mice.
Methods: Dopaminergic
D
2
R inhibition was investigated
in vitro
using Melanocytes isolated from the scale of a Tilapia. In
four separate set ups, the cells were cultured in calcium free Ringerās solution as follows; 300
Ī¼M
haloperidol, 100
Ī¼M VD
3
, 100
mM calcium chloride and a combination of 300
Ī¼M haloperidol
and
100
Ī¼M VD
3
. Subsequently, dopaminergic vesicle accumulation and calcium signalling were observed in bright field microscopy using blue and green fluorescence probes. In the second phase,
PD was induced in adult BALB/c mice (
ā
D
2
; n
=
8) after 14 days of
intraperitoneal haloperidol
treatment (10
mg/Kg). A set of n
=
4 mice were untreated (
ā
D
2
) while the other group (n
=
4) r
e-
ceived 100
mg/Kg of VD
3
for 7
days (
ā
D
2
/+VDR). The control groups (n
=
4 each) were treated with
normal saline (NS) and VD
3
(+VDR) fo
r 14 days. At the end of the treatment phase, the animals
were assessed in Rotarod, parallel bar
-
, cylinder
-
, Y
-
Maze
-
, one trial place recognition
-
and novel
object recognition
-
(NOR) tests. Neural activity was measured
using chronic electrode implants
plac
ed in the M1 (motor cortex), CPu (striatum), CA1 (hippocampus) and PFC (prefrontal cortex).
Neural activity was compared with the outcomes of behavioural tests for memory and motor fun
c-
tions and data was expressed as mean
Ā±
SEM (analysed using ANOVA with T
ukey post
-
hoc test,
significant level was set at 0.05).
Results/Discussion:
in vitro
outcomes show that VDR increase
calcium signalling and reverses the effect of haloperidol; specifically by reducing dopaminergic
vesicle accumulation in the cell body. Sim
ilarly,
in vivo
neural recordings
suggest an increase in
calcium hyperpolarization currents in the CPu and PFC of intervention mice (
ā
D
2
/+VDR) when
compared with the parkinsonian mice (
ā
D
2
). These animals (
ā
D
2
/+VDR) also recorded an i
m-
provement in spatial
working memory and motor function versus the Parkinsonian mice (
ā
D
2
).
These outcomes suggest
the role of CPu
-
PFC corticostriatal outputs in the motor
-
cognitive decline
seen in parkinsonian mice. Similarly, VDRA reduced the neural deficits through restorati
on of ca
l-
cium currents (burst activities) in the intervention mice (
ā
D
2
/+VDR).
Conclusion: VDRA treatment
reduced the motor
-
cognitive defects observed in haloperidol induced PD. Our findings suggest the
role of VDRA in restoration of calcium currents assoc
iated with PFC and CPu
corticostriatal ou
t-
puts seen as burst frequencies in
in vivo
neural recording
Building sustainable neuroscience capacity in Africa: the role of non-profit organisations
Ndams, āBuilding sustainable neuroscience capacity in Africa: the role of nonprofit organisations,āMetabolic Brain Disease
Abstract While advances in neuroscience are helping to improve many aspects of human life, inequalities exist in this field between Africa and more scientifically-advanced continents. Many African countries lack the infrastructure and appropriately-trained scientists for neuroscience education and research. Addressing these challenges would require the development of innovative approaches to help improve scientific competence for neuroscience across the continent. In recent years, science-based non-profit organisations (NPOs) have been supporting the African neuroscience community to build state-of-the-art scientific capacity for sustainable education and research. Some of these contributions have included: the establishment of training courses and workshops to introduce African scientists to powerful-yet-cost-effective experimental model systems; research infrastructural support and assistance to establish research institutes. Other contributions have come in the form of the promotion of scientific networking, public engagement and advocacy for improved neuroscience funding. Here, we discuss the contributions of NPOs to the development of neuroscience in Africa
The development of body and organ shape
Background: Organisms show an incredibly diverse array of body and organ shapes that are both unique to their taxon and important for adapting to their environment. Achieving these specific shapes involves coordinating the many processes that transform single cells into complex organs, and regulating their growth so that they can function within a fully-formed body. Main text: Conceptually, body and organ shape can be separated in two categories, although in practice these categories need not be mutually exclusive. Body shape results from the extent to which organs, or parts of organs, grow relative to each other. The patterns of relative organ size are characterized using allometry. Organ shape, on the other hand, is defined as the geometric features of an organās component parts excluding its size. Characterization of organ shape is frequently described by the relative position of homologous features, known as landmarks, distributed throughout the organ. These descriptions fall into the domain of geometric morphometrics. Conclusion: In this review, we discuss the methods of characterizing body and organ shape, the developmental programs thought to underlie each, highlight when and how the mechanisms regulating body and organ shape might overlap, and provide our perspective on future avenues of research.</p
Maintaining robust size across environmental conditions through plastic brain growth dynamics
Organ growth is tightly regulated across environmental conditions to generate an appropriate final size. While the size of some organs is free to vary, others need to maintain constant size to function properly. This poses a unique problem: how is robust final size achieved when environmental conditions alter key processes that regulate organ size throughout the body, such as growth rate and growth duration? While we know that brain growth is āsparedā from the effects of the environment from humans to fruit flies, we do not understand how this process alters growth dynamics across brain compartments. Here, we explore how this robustness in brain size is achieved by examining differences in growth patterns between the larval body, the brain and a brain compartmentāthe mushroom bodiesāin Drosophila melanogaster across both thermal and nutritional conditions. We identify key differences in patterns of growth between the whole brain and mushroom bodies that are likely to underlie robustness of final organ shape. Further, we show that these differences produce distinct brain shapes across environments
<i>Vitamin</i> D<sub>3</sub> Receptor Activation Rescued Corticostriatal Neural Activity and Improved Motor-Cognitive Function in -D<sub>2</sub>R Parkinsonian Mice Model
Disruption of mitochondrial dynamics affects behaviour and lifespan in Caenorhabditis elegans
Mitochondria are essential components of eukaryotic cells, carrying out critical physiological processes that include energy production and calcium buffering. Consequently, mitochondrial dysfunction is associated with a range of human diseases. Fundamental to their function is the ability to transition through fission and fusion states, which is regulated by several GTPases. Here, we have developed new methods for the non-subjective quantification of mitochondrial morphology in muscle and neuronal cells of Caenorhabditis elegans. Using these techniques, we uncover surprising tissue-specific differences in mitochondrial morphology when fusion or fission proteins are absent. From ultrastructural analysis, we reveal a novel role for the fusion protein FZO-1/mitofusin 2 in regulating the structure of the inner mitochondrial membrane. Moreover, we have determined the influence of the individual mitochondrial fission (DRP-1/DRP1) and fusion (FZO-1/mitofusin 1,2; EAT-3/OPA1) proteins on animal behaviour and lifespan. We show that loss of these mitochondrial fusion or fission regulators induced age-dependent and progressive deficits in animal movement, as well as in muscle and neuronal function. Our results reveal that disruption of fusion induces more profound defects than lack of fission on animal behaviour and tissue function, and imply that while fusion is required throughout life, fission is more important later in life likely to combat ageing-associated stressors. Furthermore, our data demonstrate that mitochondrial function is not strictly dependent on morphology, with no correlation found between morphological changes and behavioural defects. Surprisingly, we find that disruption of either mitochondrial fission or fusion significantly reduces median lifespan, but maximal lifespan is unchanged, demonstrating that mitochondrial dynamics play an important role in limiting variance in longevity across isogenic populations. Overall, our study provides important new insights into the central role of mitochondrial dynamics in maintaining organismal health