Malaria misdiagnosis in the routine health system in Arba Minch area district in southwest Ethiopia: an implication for malaria control and elimination

BACKGROUND

Plasmodium falciparum and Plasmodium vivax are coendemic in Ethiopia, with different proportion in different settings. Microscopy is the diagnostic tool in Ethiopian health centres. Accurate species-specific diagnosis is vital for appropriate treatment of cases to interrupt its transmission. Therefore, this study assessed the status of species-specific misdiagnosis by microscope compared with polymerase chain reaction (PCR).

METHODS

A health facility based cross-sectional study was conducted from November 2019 to January 2020 in Kolla Shelle Health centre, Arba Minch Zuria district. The study population were suspected malaria cases, who visited the health centre for a diagnosis and treatment. Consecutive microscopy positive cases as well as a sample of microscopically negative cases were included for molecular analysis by polymerase chain reaction (PCR).

RESULTS

254 microscopically negative and 193 microscopically positive malaria suspects were included. Of the 193 malaria positive cases, 46.1% [95% confidence interval (CI) 38.9-53.4] (89/193) were P. falciparum infection, 52.3% (95% CI 45.0-59.5) (101/193) were P. vivax infection, and 1.6% (3/193) had mixed infection of P. falciparum and P. vivax. Of the microscopically positive cases of P. falciparum, 3.4% (3/89) were P. vivax and 11.2% (10/89) were mixed infections with P. falciparum and P. vivax and a single case was negative molecularly. Similarly, of the microscopically positive P. vivax cases, 5.9% (6/101) were P. falciparum and 1% (1/101) was mixed infection. Single case was negative by molecular technique. Of the 254 microscopically negative cases, 0.8% were tested positive for P. falciparum and 2% for P. vivax by PCR. Considering molecular technique as a reference, the sensitivity of microscopy for detecting P. falciparum was 89.2% and for P. vivax, it was 91.2%. The specificity of microscopy for detecting P. falciparum was 96.1% and for P. vivax, it was 97.7%. However, the sensitivity of microscopy in detecting mixed infection of P. falciparum and P. vivax was low (8.3%).

CONCLUSION

There were cases left untreated or inappropriately treated due to the species misidentification. Therefore, to minimize this problem, the gaps in the microscopic-based malaria diagnosis should be identified. It is recommended to regularly monitor the competency of malaria microscopists in the study area to improve species identification and diagnosis accuracy.

Hippocampal delivery of neurotrophic factor-α1/carboxypeptidase E gene prevents neurodegeneration, amyloidosis, memory loss in Alzheimer's Disease male mice

Alzheimer's Disease (AD) is a prevalent neurodegenerative disease characterized by tau hyperphosphorylation, Aβ1-42 aggregation and cognitive dysfunction. Therapeutic agents directed at mitigating tau aggregation and clearing Aβ1-42, and delivery of growth factor genes (BDNF, FGF2), have ameliorated cognitive deficits, but these approaches did not prevent or stop AD progression. Here we report that viral-(AAV) delivery of Neurotrophic Factor-α1/Carboxypeptidase E (NF-α1/CPE) gene in hippocampus at an early age prevented later development of cognitive deficits as assessed by Morris water maze and novel object recognition assays, neurodegeneration, and tau hyperphosphorylation in male 3xTg-AD mice. Additionally, amyloid precursor protein (APP) expression was reduced to near non-AD levels, and insoluble Aβ1-42 was reduced significantly. Pro-survival proteins: mitochondrial Bcl2 and Serpina3g were increased; and mitophagy inhibitor Plin4 and pro-inflammatory protein Card14 were decreased in AAV-NF-α1/CPE treated versus untreated AD mice. Thus NF-α1/CPE gene therapy targets many regulatory components to prevent cognitive deficits in 3xTg-AD mice and has implications as a new therapy to prevent AD progression by promoting cell survival, inhibiting APP overexpression and tau hyperphosphorylation.

Alzheimer's disease/dementia-associated brain pathology in aging DPP6-KO mice

We have previously reported that the single transmembrane protein Dipeptidyl Peptidase Like 6 (DPP6) impacts neuronal and synaptic development. DPP6-KO mice are impaired in hippocampal-dependent learning and memory and exhibit smaller brain size. Recently, we have described novel structures in hippocampal area CA1 in aging mice, apparently derived from degenerating presynaptic terminals, that are significantly more prevalent in DPP6-KO mice compared to WT mice of the same age and that these structures were observed earlier in development in DPP6-KO mice. These novel structures appear as clusters of large puncta that colocalize NeuN, synaptophysin, and chromogranin A, and also partially label for MAP2, amyloid β, APP, α-synuclein, and phosphorylated tau, with synapsin-1 and VGluT1 labeling on their periphery. In this current study, using immunofluorescence and electron microscopy, we confirm that both APP and amyloid β are prevalent in these structures; and we show with immunofluorescence the presence of similar structures in humans with Alzheimer's disease. Here we also found evidence that aging DPP6-KO mutants show additional changes related to Alzheimer's disease. We used in vivo MRI to show reduced size of the DPP6-KO brain and hippocampus. Aging DPP6-KO hippocampi contained fewer total neurons and greater neuron death and had diagnostic biomarkers of Alzheimer's disease present including accumulation of amyloid β and APP and increase in expression of hyper-phosphorylated tau. The amyloid β and phosphorylated tau pathologies were associated with neuroinflammation characterized by increases in microglia and astrocytes. And levels of proinflammatory or anti-inflammatory cytokines increased in aging DPP6-KO mice. We finally show that aging DPP6-KO mice display circadian dysfunction, a common symptom of Alzheimer's disease. Together these results indicate that aging DPP6-KO mice show symptoms of enhanced neurodegeneration reminiscent of dementia associated with a novel structure resulting from synapse loss and neuronal death. This study continues our laboratory's work in discerning the function of DPP6 and here provides compelling evidence of a direct role of DPP6 in Alzheimer's disease.

An integrated care pathway for maternal and childcare: evidence from Ethiopia, Tanzania, and Uganda

 

Performance monitoring and evaluation are key to quality improvement in maternal and child healthcare in Sub-Saharan Africa. This study presents the experience of designing and implementing bottom-up and integrated performance evaluation tools for care pathway to monitor and manage maternity healthcare services. The research project involved four health districts and relative reference hospitals, supported by the NGO Doctors with Africa CUAMM in Ethiopia, Tanzania, and Uganda. The maternal and childcare pathway developed consists of 23 indicators, calculated at hospital and district level, relating to pregnancy, childbirth and first year of life phases. The authors developed staves and performance maps, as graphical representation tools, to display longitudinally integrated health services provision performance along the continuum of care. Substantial variation was observed between the phases of each maternal and childcare pathway and across the care pathways of the different analysed settings. The most impressive results across the four settings are: 1) regarding pregnancy phase, that women tend to attend more than four antenatal classes, still with a quite high drop-out rate, and are largely tested for syphilis, 2) with respect to childbirth, that there are varying percentage levels in terms of C-sections, episiotomies and peri/intra-partum asphyxia cases, and 3) as it regards first year of life, there emerges scope for improvement considering the vaccination coverages attained for pentavalent, measles and polio vaccinations. Thanks to the collaboration with local managers and health professionals, the maternal and childcare pathway allowed to monitor the changes in the quality of maternity services provided within the analysed contexts. The benchmarking approach encouraged local professionals to learn from other settings. The use of such tool allowed the development of targeted quality improvement actions, shared among all involved stakeholders.

Key messages

• In collaboration with local professionals, we designed and implemented an integrated pathway for maternal and childcare, covering the phases of pregnancy, childbirth and first year of life.

• Benchmarking performance results encouraged collaboration among professionals and allowed the identification of actions to improve the provision of maternal and childcare services.

An integrated hospital-district evaluation for communicable diseases in low/middle-income countries

Background

The last two decades saw an extensive effort to design and implement integrated and multidimensional healthcare evaluation systems in high-income countries. However, in low/middle-income countries, few experiences of such systems implementation have been reported in the scientific literature. We developed and piloted an innovative tool to assess the performance of health services provision for communicable diseases in three African countries.

Methods

A total of 42 indicators, 14 per each communicable disease care pathway (Tuberculosis, Gastroenteritis, and HIV/AIDS), were developed. A sub-set of 23 indicators was included in the evaluation process. The indicators assessed four care phases: prevention, diagnosis, treatment, and outcome. All indicators were calculated for the period 2017-2019, while performance evaluation was performed for 2019. The analysis involved four health districts and their relative hospitals in Ethiopia, Tanzania, and Uganda.

Results

Substantial variability was observed over time and across the four different districts. In the TB pathway, the majority of indicators scored below the standards and below-average performance was mainly reported for prevention and diagnosis phases. Along the Gastroenteritis pathway, excellent performance was instead evaluated for most indicators and the highest scores were reported in prevention and treatment phases. The HIV/AIDS pathway indicators related to screening and outcome phases were below the average score, while good or excellent performance was registered within the treatment phase.

Conclusions

The bottom-up approach and stakeholders’ engagement increased local ownership of the process and the likelihood that findings will inform health services performance and quality of care. Despite the intrinsic limitations of data sources, this framework may contribute to promoting good governance, performance evaluation and accountability in settings characterised by multiple healthcare service providers.

Key messages

• A successful experience in developing and implementing a communicable diseases performance evaluation systems in three sub-Saharan African countries using a bottom-up approach.

• The communicable diseases performance evaluation tool helped the data sharing between local healthcare providers and the development of competencies in data collection, analysis and interpretation.

Resilient Hippocampal Gamma Rhythmogenesis and Parvalbumin-Expressing Interneuron Function Before and After Plaque Burden in 5xFAD Alzheimer's Disease Model

Recent studies have implicated impaired Parvalbumin Fast-Spiking Interneuron (PVIN) function as a precipitating factor underlying abnormalities in network synchrony, oscillatory rhythms, and cognition associated with Alzheimer's disease (AD). However, a complete developmental investigation of potential gamma deficits, induced by commonly used carbachol or kainate in ex vivo slice preparations, within AD model mice is lacking. We examined gamma oscillations using field recordings in acute hippocampal slices from 5xFAD and control mice, through the period of developing pathology, starting at 3 months of age, when there is minimal plaque presence in the hippocampus, through to 12+ months of age, when plaque burden is high. In addition, we examined PVIN participation in gamma rhythms using targeted cell-attached recordings of genetically-reported PVINs, in both wild type and mutant mice. In parallel, a developmental immunohistochemical characterisation probing the PVIN-associated expression of PV and perineuronal nets (PNNs) was compared between control and 5xFAD mice. Remarkably, this comprehensive longitudinal evaluation failed to reveal any obvious correlations between PVIN deficits (electrical and molecular), circuit rhythmogenesis (gamma frequency and power), and Aβ deposits/plaque formation. By 6-12 months, 5xFAD animals have extensive plaque formation throughout the hippocampus. However, a deficit in gamma oscillatory power was only evident in the oldest 5xFAD animals (12+ months), and only when using kainate, and not carbachol, to induce the oscillations. We found no difference in PV firing or phase preference during kainate-induced oscillations in younger or older 5xFAD mice compared to control, and a reduction of PV and PNNs only in the oldest 5xFAD mice. The lack of a clear relationship between PVIN function, network rhythmicity, and plaque formation in our study highlights an unexpected resilience in PVIN function in the face of extensive plaque pathology associated with this model, calling into question the presumptive link between PVIN pathology and Alzheimer's progression.

Complex N-Linked Glycosylation: A Potential Modifier of Niemann-Pick Disease, Type C1 Pathology

Complex asparagine-linked glycosylation plays key roles in cellular functions, including cellular signaling, protein stability, and immune response. Previously, we characterized the appearance of a complex asparagine-linked glycosylated form of lysosome-associated membrane protein 1 (LAMP1) in the cerebellum of Npc1^-/- mice. This LAMP1 form was found on activated microglia, and its appearance correlated both spatially and temporally with cerebellar Purkinje neuron loss. To test the importance of complex asparagine-linked glycosylation in NPC1 pathology, we generated NPC1 knock-out mice deficient in MGAT5, a key Golgi-resident glycosyl transferase involved in complex asparagine-linked glycosylation. Our results show that Mgat5^-/-:Npc1^-/- mice were smaller than Mgat5^+/+:Npc1^-/- mice, and exhibited earlier NPC1 disease onset and reduced lifespan. Western blot and lectin binding analyses of cerebellar extracts confirmed the reduction in complex asparagine-linked glycosylation, and the absence of the hyper-glycosylated LAMP1 previously observed. Western blot analysis of cerebellar extracts demonstrated reduced calbindin staining in Mgat5^-/-:Npc1^-/- mice compared to Mgat5^+/+:Npc1^-/- mutant mice, and immunofluorescent staining of cerebellar sections indicated decreased levels of Purkinje neurons and increased astrogliosis in Mgat5^-/-:Npc1^-/- mice. Our results suggest that reduced asparagine-linked glycosylation increases NPC1 disease severity in mice, and leads to the hypothesis that mutations in genes involved in asparagine-linked glycosylation may contribute to disease severity progression in individuals with NPC1. To examine this with respect to MGAT5, we analyzed 111 NPC1 patients for two MGAT5 SNPs associated with multiple sclerosis; however, we did not identify an association with NPC1 phenotypic severity.

Overweight and obesity among non-pregnant women of reproductive age in Nigeria: findings from the 2008-2018 Nigerian Demographic and Health Survey

OBJECTIVES

Overweight and obesity are known risk factors for diabetes, heart disease, certain cancers and pregnancy-related problems. This study aimed to determine the prevalence and change in prevalence of overweight and obesity among non-pregnant women of reproductive age and relationship with individual- and community-level factors over a decade.

STUDY DESIGN

This was a cross-sectional survey with two-stage probability sampling design.

METHODS

Data sets were pooled from the 2008, 2013 and 2018 Nigerian Demographic and Health Survey - a cross-sectional, nationally representative sample of the entire Nigerian population aged 15-49 years. Body mass index (BMI) was used to classify overweight and obesity. Multilevel logistic regression was used to assess associations between overweight (25.0-29.9 kg/m²), obesity (≥30.0 kg/m²) and individual and community factors.

RESULTS

There were 76,729 non-pregnant women (38.0% in 2008, 44.5% in 2013 vs 17.5% in 2018) with a mean age of 29.0 years and a BMI of 23.0 kg/m² across the three survey periods. Overweight and obesity prevalence were 16.0% and 6.2% in 2008, 17.2% and 7.5% in 2013 and 18.1% and 9.9% in 2018, respectively. There was 76% (95% confidence interval: 44% to twofold) increased odds of obesity in 2018 compared with 2008 in adjusted analysis. Older women with at least primary education living in urban areas, ever married and from wealthier households are at a greater odd of being overweight and obese.

CONCLUSION

Over a decade, overweight and obesity prevalence increased among non-pregnant women of reproductive age in Nigeria. There is an urgent need for public health strategies and interventions to improve on deficient knowledge and low awareness about healthy foods and physical activity at individual and community levels especially in urban areas.

Synaptic Vesicle Precursors and Lysosomes Are Transported by Different Mechanisms in the Axon of Mammalian Neurons

BORC is a multisubunit complex previously shown to promote coupling of mammalian lysosomes and C. elegans synaptic vesicle (SV) precursors (SVPs) to kinesins for anterograde transport of these organelles along microtubule tracks. We attempted to meld these observations into a unified model for axonal transport in mammalian neurons by testing two alternative hypotheses: (1) that SV and lysosomal proteins are co-transported within a single type of “lysosome-related vesicle” and (2) that SVPs and lysosomes are distinct organelles, but both depend on BORC for axonal transport. Analyses of various types of neurons from wild-type rats and mice, as well as from BORC-deficient mice, show that neither hypothesis is correct. We find that SVPs and lysosomes are transported separately, but only lysosomes depend on BORC for axonal transport in these neurons. These findings demonstrate that SVPs and lysosomes are distinct organelles that rely on different machineries for axonal transport in mammalian neurons.

De Pace et al. show that lysosomes and synaptic vesicle precursors (SVPs) are distinct organelles that move separately from the soma to the axon in rat and mouse neurons. Moreover, they demonstrate that the BLOC-1-related complex (BORC) is required for the transport of lysosomes but not SVPs in mouse neurons.

Neurotrophic factor-α1, a novel tropin is critical for the prevention of stress-induced hippocampal CA3 cell death and cognitive dysfunction in mice: comparison to BDNF

Stress leads to brain pathology including hippocampal degeneration, cognitive dysfunction, and potential mood disorders. Hippocampal CA3, a most stress-vulnerable region, consists of pyramidal neurons that regulate cognitive functions e.g. learning and memory. These CA3 neurons express high levels of the neuroprotective protein, neurotrophic factor-α1 (NF-α1), also known as carboxypeptidase E (CPE), and receive contacts from granule cell projections that release BDNF which has neuroprotective activity. Whether NF-α1-CPE and/or BDNF are critical in protecting these CA3 neurons against severe stress-induced cell death is unknown. Here we show that social combined with the physical stress of maternal separation, ear tagging, and tail snipping at weaning in 3-week-old mice lacking NF-α1-CPE, led to complete hippocampal CA3 degeneration, despite having BDNF and active phosphorylated TrkB receptor levels similar to WT animals. Mice administered TrkB inhibitor, ANA12 which blocked TrkB phosphorylation showed no degeneration of the CA3 neurons after the weaning stress paradigm. Furthermore, transgenic knock-in mice expressing CPE-E342Q, an enzymatically inactive form, replacing NF-α1-CPE, showed no CA3 degeneration and exhibited normal learning and memory after the weaning stress, unlike NF-α1-CPE-KO mice. Mechanistically, we showed that radio-labeled NF-α1-CPE bound HT22 hippocampal cells in a saturable manner and with high affinity (Kd = 4.37 nM). Subsequently, treatment of the HT22^cpe-/- cells with NF-α1-CPE or CPE-E342Q equivalently activated ERK signaling and increased BCL2 expression to protect these neurons against H₂O₂-or glutamate-induced cytotoxicity. Our findings show that NF-α1-CPE is more critical compared to BDNF in protecting CA3 pyramidal neurons against stress-induced cell death and cognitive dysfunction, independent of its enzymatic activity.

Incidence and risk factors for hospital-acquired infection among paediatric patients in a teaching hospital: a prospective study in southeast Ethiopia

OBJECTIVES

In order to maximise the prevention of hospital-acquired infections (HAIs) and antimicrobial resistance, data on the incidence of HAIs are crucial. In Ethiopia, data about the occurrence of HAIs among hospitalised paediatric patients are lacking. We aim to determine the incidence and risk factors of HAIs among paediatric patients in Ethiopia.

DESIGN

A prospective cohort study.

SETTING

A teaching hospital in southeast Ethiopia.

PARTICIPANTS

448 hospitalised paediatric patients admitted between 1 November 2018 and 30 June 2019.

PRIMARY AND SECONDARY OUTCOME MEASURES

Incidence and risk factors of hospital-acquired infections.

RESULTS

A total of 448 paediatric patients were followed for 3227 patient days. The median age of the patients was 8 months (IQR: 2-26 months). The incidence rate of HAIs was 17.7 per 1000 paediatric days of follow-up; while the overall cumulative incidence was 12.7% (95% CI 9.8% to 15.8%) over 8 months. Children who stayed greater than 6 days in the hospital (median day) (adjusted risk ratio (RR): 2.58, 95% CI 1.52 to 4.38), and children with underlying disease conditions of severe acute malnutrition (adjusted RR: 2.83, 95% CI 1.61 to 4.97) had higher risks of developing HAIs.

CONCLUSIONS

The overall cumulative incidence of HAIs was about 13 per 100 admitted children. Length of stay in the hospital and underlying conditions of severe acute malnutrition were found to be important factors associated with increased risk of HAIs.

SUN-260 Dual Role of Carboxypeptidase E in Prohormone Processing and a Novel Neurotrophic Factor Mediating Neuroprotection and Cognitive Functions in Hippocampal CA3 Neurons in Mice

Stress causes release of glucocorticoids from the adrenals which then circulate to the brain. High concentrations glucocorticoid from chronic severe stress results in pathophysiology in the brain, including neuronal degeneration, cell death and cognitive dysfunction, leading to diseases such as Alzheimer Disease and Major Depressive Disorders. Neurotrophic/growth factors such as BDNF, NGF and NT3 have been linked to these pathological conditions. Carboxypeptidase E (CPE), a proneuropeptide/prohormone processing enzyme, also named neurotrophic factor-α1(NFα1) is highly expressed in the stress-vulnerable hippocampal CA3 neurons, and was shown to have neuroprotective activity from in vitro studies. Here we investigated if CPE-NFα1 functions in vivo, independent of its enzymatic activity, and the mechanism underlying its action. We generated knock-in mice expressing a non-enzymatic form of CPE, CPE-E342Q, but not wild-type CPE. The CPE-E342Q mice showed significantly decreased neuropeptide content and exhibited obesity, diabetes and infertility due to lack of prohormone processing activity, similar to CPE-KO mice. However, they showed no hippocampal CA3 degeneration, exhibited neurogenesis in the dentate gyrus, and displayed normal spatial learning and memory, similar to CPE wild-type mice, after weaning stress; unlike CPE-KO mice which showed hippocampal CA3 neuronal degeneration and cognitive deficits. Binding studies showed that radiolabeled CPE bound hippocampal cell membrane specifically, in a saturable manner. Binding of CPE and CPE-E342Q to hippocampal neurons activated Erk signaling and pre-treatment with either of these proteins protected neurons against H₂O₂- or glutamate-induced neurotoxcity by increasing BCL2 expression. In vitro and in vivo inhibitor studies demonstrated that this neuroprotective effect was independent of tyrosine kinase receptor signaling. Taken together, the data provide evidence that CPE-NFα1 is a unique neurotrophic factor which acts through a non-tyrosine kinase receptor to activate Erk-BCL2 signaling to protect hippocampal CA3 neurons against stress-induced neurodegeneration and maintaining normal cognitive functions in mice.

Activity-dependent isomerization of Kv4.2 by Pin1 regulates cognitive flexibility

Voltage-gated K+ channels function in macromolecular complexes with accessory subunits to regulate brain function. Here, we describe a peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (Pin1)-dependent mechanism that regulates the association of the A-type K+ channel subunit Kv4.2 with its auxiliary subunit dipeptidyl peptidase 6 (DPP6), and thereby modulates neuronal excitability and cognitive flexibility. We show that activity-induced Kv4.2 phosphorylation triggers Pin1 binding to, and isomerization of, Kv4.2 at the pThr607-Pro motif, leading to the dissociation of the Kv4.2-DPP6 complex. We generated a novel mouse line harboring a knock-in Thr607 to Ala (Kv4.2TA) mutation that abolished dynamic Pin1 binding to Kv4.2. CA1 pyramidal neurons of the hippocampus from these mice exhibited altered Kv4.2-DPP6 interaction, increased A-type K+ current, and reduced neuronal excitability. Behaviorally, Kv4.2TA mice displayed normal initial learning but improved reversal learning in both Morris water maze and lever press paradigms. These findings reveal a Pin1-mediated mechanism regulating reversal learning and provide potential targets for the treatment of neuropsychiatric disorders characterized by cognitive inflexibility.

Paradoxical network excitation by glutamate release from VGluT3+ GABAergic interneurons

In violation of Dale's principle several neuronal subtypes utilize more than one classical neurotransmitter. Molecular identification of vesicular glutamate transporter three and cholecystokinin expressing cortical interneurons (CCK+VGluT3+INTs) has prompted speculation of GABA/glutamate corelease from these cells for almost two decades despite a lack of direct evidence. We unequivocally demonstrate CCK+VGluT3+INT-mediated GABA/glutamate cotransmission onto principal cells in adult mice using paired recording and optogenetic approaches. Although under normal conditions, GABAergic inhibition dominates CCK+VGluT3+INT signaling, glutamatergic signaling becomes predominant when glutamate decarboxylase (GAD) function is compromised. CCK+VGluT3+INTs exhibit surprising anatomical diversity comprising subsets of all known dendrite targeting CCK+ interneurons in addition to the expected basket cells, and their extensive circuit innervation profoundly dampens circuit excitability under normal conditions. However, in contexts where the glutamatergic phenotype of CCK+VGluT3+INTs is amplified, they promote paradoxical network hyperexcitability which may be relevant to disorders involving GAD dysfunction such as schizophrenia or vitamin B6 deficiency.

Divergent expression patterns of pituitary gonadotropin subunit and GnRH receptor genes to continuous GnRH in vitro and in vivo

Continuous, as opposed to pulsatile, delivery of hypothalamic gonadotropin-releasing hormone (GnRH) leads to a marked decrease in secretion of pituitary gonadotropins LH and FSH and impairment of reproductive function. Here we studied the expression profile of gonadotropin subunit and GnRH receptor genes in rat pituitary in vitro and in vivo to clarify their expression profiles in the absence and continuous presence of GnRH. Culturing of pituitary cells in GnRH-free conditions downregulated Fshb, Cga, and Gnrhr expression, whereas continuous treatment with GnRH agonists upregulated Cga expression progressively and Gnrhr and Fshb expression transiently, accompanied by a prolonged blockade of Fshb but not Gnrhr expression. In contrast, Lhb expression was relatively insensitive to loss of endogenous GnRH and continuous treatment with GnRH, probably reflecting the status of Egr1 and Nr5a1 expression. Similar patterns of responses were observed in vivo after administration of a GnRH agonist. However, continuous treatment with GnRH stimulated LH secretion in vitro and in vivo, leading to decrease in LH cell content despite high basal Lhb expression. These data suggest that blockade of Fshb expression and depletion of the LH secretory pool are two major factors accounting for weakening of the gonadotroph secretory function during continuous GnRH treatment.

Schwann-Cell-Specific Deletion of Phosphatidylinositol 4-Kinase Alpha Causes Aberrant Myelination

Active membrane remodeling during myelination relies on phospholipid synthesis and membrane polarization, both of which are known to depend on inositol phospholipids. Here, we show that sciatic nerves of mice lacking phosphatidylinositol 4-kinase alpha (PI4KA) in Schwann cells (SCs) show substantially reduced myelin thickness with grave consequences on nerve conductivity and motor functions. Surprisingly, prolonged inhibition of PI4KA in immortalized mouse SCs failed to decrease plasma membrane phosphatidylinositol 4,5-bisphosphate (PI(4,5)P₂) levels or PI 3-kinase (PI3K) activation, in spite of large reductions in plasma membrane PI4P levels. Instead, it caused rearrangements of the actin cytoskeleton, which was also observed in sciatic nerves of knockout animals. PI4KA inactivation disproportionally reduced phosphatidylserine, phosphatidylethanolamine, and sphingomyelin content in mutant nerves, with similar changes observed in SCs treated with a PI4KA inhibitor. These studies define a role for PI4KA in myelin formation primarily affecting metabolism of key phospholipids and the actin cytoskeleton.

Distinct Expression Patterns of Osteopontin and Dentin Matrix Protein 1 Genes in Pituitary Gonadotrophs

Cell-matrix interactions play important roles in pituitary development, physiology, and pathogenesis. In other tissues, a family of non-collagenous proteins, termed SIBLINGs, are known to contribute to cell-matrix interactions. Anterior pituitary gland expresses two SIBLING genes, Dmp1 (dentin matrix protein-1) and Spp1 (secreted phosphoprotein-1) encoding DMP1 and osteopontin proteins, respectively, but their expression pattern and roles in pituitary functions have not been clarified. Here we provide novel evidence supporting the conclusion that Spp1/osteopontin, like Dmp1/DMP1, are expressed in gonadotrophs in a sex- and age-specific manner. Other anterior pituitary cell types do not express these genes. In contrast to Dmp1, Spp1 expression is higher in males; in females, the expression reaches the peak during the diestrus phase of estrous cycle. In further contrast to Dmp1 and marker genes for gonadotrophs, the expression of Spp1 is not regulated by gonadotropin-releasing hormone in vivo and in vitro. However, Spp1 expression increases progressively after pituitary cell dispersion in both female and male cultures. We may speculate that gonadotrophs signal to other pituitary cell types about changes in the structure of pituitary cell-matrix network by osteopontin, a function consistent with the role of this secretory protein in postnatal tissue remodeling, extracellular matrix reorganization after injury, and tumorigenesis.

Neto Auxiliary Subunits Regulate Interneuron Somatodendritic and Presynaptic Kainate Receptors to Control Network Inhibition

Although Netos are considered auxiliary subunits critical for kainate receptor (KAR) function, direct evidence for their regulation of native KARs is limited. Because Neto KAR regulation is GluK subunit/Neto isoform specific, such regulation must be determined in cell-type-specific contexts. We demonstrate Neto1/2 expression in somatostatin (SOM)-, cholecystokinin/cannabinoid receptor 1 (CCK/CB1)-, and parvalbumin (PV)-containing interneurons. KAR-mediated excitation of these interneurons is contingent upon Neto1 because kainate yields comparable effects in Neto2 knockouts and wild-types but fails to excite interneurons or recruit inhibition in Neto1 knockouts. In contrast, presynaptic KARs in CCK/CB1 interneurons are dually regulated by both Neto1 and Neto2. Neto association promotes tonic presynaptic KAR activation, dampening CCK/CB1 interneuron output, and loss of this brake in Neto mutants profoundly increases CCK/CB1 interneuron-mediated inhibition. Our results confirm that Neto1 regulates endogenous somatodendritic KARs in diverse interneurons and demonstrate Neto regulation of presynaptic KARs in mature inhibitory presynaptic terminals.

DPP6 Loss Impacts Hippocampal Synaptic Development and Induces Behavioral Impairments in Recognition, Learning and Memory

DPP6 is well known as an auxiliary subunit of Kv4-containing, A-type K⁺ channels which regulate dendritic excitability in hippocampal CA1 pyramidal neurons. We have recently reported, however, a novel role for DPP6 in regulating dendritic filopodia formation and stability, affecting synaptic development and function. These results are notable considering recent clinical findings associating DPP6 with neurodevelopmental and intellectual disorders. Here we assessed the behavioral consequences of DPP6 loss. We found that DPP6 knockout (DPP6-KO) mice are impaired in hippocampus-dependent learning and memory. Results from the Morris water maze and T-maze tasks showed that DPP6-KO mice exhibit slower learning and reduced memory performance. DPP6 mouse brain weight is reduced throughout development compared with WT, and in vitro imaging results indicated that DPP6 loss affects synaptic structure and motility. Taken together, these results show impaired synaptic development along with spatial learning and memory deficiencies in DPP6-KO mice.

The burden of road traffic injuries in an emergency department in Addis Ababa, Ethiopia

SETTING

The emergency department (ED) of Zewditu Memorial Hospital, Addis Ababa, Ethiopia.

OBJECTIVE

To document the proportion, trend, characteristics and outcomes of road traffic injury (RTI) related ED admissions (⩾15 years) between 2014 and 2015.

DESIGN

A retrospective, cross-sectional study using routinely collected ED data.

RESULTS

Of 10 007 ED admissions, 779 (8%) were RTI cases; this proportion peaked in the month of January (11%). Medical records were available for 522 (67%) of these RTI cases. The median age was 28 years and 69% were males. The majority were pedestrians (69%) injured by an automobile (78%). On triage, 32% were classified as needing urgent/immediate intervention. Head injuries (20%) were the second most common injury after lower limb injuries (36%). ED outcomes were as follows: discharged (68%), hospitalised (17%), referred (17%) and died (1%). Among the 78 hospitalised cases, respectively 62% and 16% were admitted to the surgical and orthopaedic departments. Of 146 RTI cases with head injuries, 25% were hospitalised, of whom 82% were admitted to the surgical department.

CONCLUSION

Our findings can guide policy makers in referral hospitals in improving the planning of hospital resources and the prioritisation of public health needs linked to further urban development. A comprehensive plan to prevent RTIs, particularly among pedestrians in Addis Ababa, is urgently needed.

Determination of Corynebacterium pseudotuberculosis prevalence and antimicrobial susceptibility pattern of isolates from lymph nodes of sheep and goats at an organic export abattoir, Modjo, Ethiopia

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis, a suppurative abscessation in the superficial and internal lymph nodes and internal organs of small ruminants. This study was conducted on the superficial lymph nodes and carcasses of 768 small ruminants slaughtered at a slaughterhouse during the study period; 82 had abscesses or caseous lymphadenitis. The most frequent sites of abscesses in goats were the prescapular (34, 5·54%) and prefemoral lymph nodes (24, 3·91%) respectively. Similar patterns were observed in sheep. The prevalence of caseous lymphadenitis was found to be significantly higher in adult than in young animals, in both species (P < 0·05). The age-wise prevalence rates of lesions on post-mortem inspection, at 95% CI, were 2·7% (2·3-3·1%) and 3·1% (2·8-3·4%) in young sheep and goats, respectively, and 24·4% (17·4-31·4%) and 27·5% (23·8-31·2%) in adult sheep and goats respectively. Corynebacterium pseudotuberculosis isolates were recovered from 72% (59/82) of animals found to have post-mortem evidence of abscesses. The Coryne. pseudotuberculosis isolates were susceptible to the antibiotics norfloxacin, tetracycline, doxycyline HCl and kanamycine; however, resistance was observed against ampicillin, clindamycin and doxycyline HCl. In conclusion, this study reported the magnitude of the problem in the country for the first time and the authors recommend a thorough investigation of wider study areas.

SIGNIFICANCE AND IMPACT OF THE STUDY

This work presents data on the prevalence of caseous lymphadenitis in slaughtered sheep and goats as well as the isolation and antibiotic susceptibility pattern of Corynebacterium pseudotuberculosis for the first time in Ethiopia. The carcasses of small ruminants are the major livestock product exported from the country and serves as an important source of foreign currency. Assessing the impact of diseases such as caseous lymphadenitis in the industry would be of great significance. This work forms initial data that call for further wider investigations to gain complete understanding of its impact in the country.

Neuroprotective peptides influence cytokine and chemokine alterations in a model of fetal alcohol syndrome

OBJECTIVE

Fetal alcohol syndrome (FAS) is associated with intellectual disability and neurodevelopmental abnormalities. Neuroprotective peptides NAPVSIPQ (NAP) and SALLRSIPA (SAL) can prevent some of the alcohol-induced teratogenesis including fetal death, growth abnormalities, and learning impairment in part by preventing alcohol-induced alterations in N-methyl-D-aspartate receptor gene expression in a mouse model for FAS. We evaluated a panel of cytokines and chemokines to determine whether NAP plus SAL work through a cytokine/chemokine-mediated pathway in preventing these alterations.

STUDY DESIGN

Using a well-characterized FAS model, timed, pregnant C57BL6/J mice were treated on gestational day (E) 8 with alcohol (0.03 mL/g), placebo, or alcohol plus peptides. Embryos were evaluated at 2 time points: after 6 hours and 10 days later at E18. A panel of cytokines/chemokines was measured using a microsphere-based multiplex immunoassay (Luminex xMAP; Millipore, Billerica, MA). Statistical analysis included Kruskal-Wallis, with P < .05 considered significant.

RESULTS

Six hours after treatment, interleukin (IL)-6 and keratinocyte chemoattractant cytokine (KC) were not detectable in the control embryos. Alcohol treatment resulted in detectable levels and significant increases in IL-6 (median, 15.7; range, 10.1-45.9 pg/mL) and KC (median, 45.9; range, 32.5-99.1 pg/mL). Embryos exposed to alcohol plus NAP plus SAL had undetectable IL-6 and KC (both P < .003), similar to the controls. Alcohol exposure resulted in a significant increase of granulocyte colony-stimulating factor (G-CSF) (P < .003) as compared with controls, and treatment with NAP plus SAL prevented the alcohol-induced increase. IL-13 and IL-1β were decreased 6 hours after alcohol exposure, and exposure to alcohol plus NAP plus SAL did not completely ameliorate the decrease. At E18, 10 days after exposure, these alterations were no longer present. Several analytes (regulated upon activation, normal T cell expressed, and secreted, tumor necrosis factor-α, interferon-γ, and IL-4) were not detectable at either time point in any of the groups.

CONCLUSION

Prenatal alcohol exposure acutely results in a significant elevation of IL-6, G-CSF and the KC, which are known to affect N-methyl-D-aspartate receptors. NAP plus SAL treatment prevented alcohol-induced increases. This provides additional insight into the mechanism of alcohol damage in FAS and NAP plus SAL prevention of neurodevelopmental anomalies.

Prenatal treatment prevents learning deficit in Down syndrome model

Down syndrome is the most common genetic cause of mental retardation. Active fragments of neurotrophic factors release by astrocyte under the stimulation of vasoactive intestinal peptide, NAPVSIPQ (NAP) and SALLRSIPA (SAL) respectively, have shown therapeutic potential for developmental delay and learning deficits. Previous work demonstrated that NAP+SAL prevent developmental delay and glial deficit in Ts65Dn that is a well-characterized mouse model for Down syndrome. The objective of this study is to evaluate if prenatal treatment with these peptides prevents the learning deficit in the Ts65Dn mice. Pregnant Ts65Dn female and control pregnant females were randomly treated (intraperitoneal injection) on pregnancy days 8 through 12 with saline (placebo) or peptides (NAP 20 µg +SAL 20 µg) daily. Learning was assessed in the offspring (8–10 months) using the Morris Watermaze, which measures the latency to find the hidden platform (decrease in latency denotes learning). The investigators were blinded to the prenatal treatment and genotype. Pups were genotyped as trisomic (Down syndrome) or euploid (control) after completion of all tests. Statistical analysis: two-way ANOVA followed by Neuman-Keuls test for multiple comparisons, P<0.05 was used to denote statistical significance. Trisomic mice who prenatally received placebo (Down syndrome -placebo; n = 11) did not demonstrate learning over the five day period. DS mice that were prenatally exposed to peptides (Down syndrome-peptides; n = 10) learned significantly better than Down syndrome -placebo (p<0.01), and similar to control-placebo (n = 33) and control-peptide (n = 30). In conclusion prenatal treatment with the neuroprotective peptides (NAP+SAL) prevented learning deficits in a Down syndrome model. These findings highlight a possibility for the prevention of sequelae in Down syndrome and suggest a potential pregnancy intervention that may improve outcome.

Antiretroviral preexposure prophylaxis for heterosexual HIV transmission in Botswana

BACKGROUND

Preexposure prophylaxis with antiretroviral agents has been shown to reduce the transmission of human immunodeficiency virus (HIV) among men who have sex with men; however, the efficacy among heterosexuals is uncertain.

METHODS

We randomly assigned HIV-seronegative men and women to receive either tenofovir disoproxil fumarate and emtricitabine (TDF-FTC) or matching placebo once daily. Monthly study visits were scheduled, and participants received a comprehensive package of prevention services, including HIV testing, counseling on adherence to medication, management of sexually transmitted infections, monitoring for adverse events, and individualized counseling on risk reduction; bone mineral density testing was performed semiannually in a subgroup of participants.

RESULTS

A total of 1219 men and women underwent randomization (45.7% women) and were followed for 1563 person-years (median, 1.1 years; maximum, 3.7 years). Because of low retention and logistic limitations, we concluded the study early and followed enrolled participants through an orderly study closure rather than expanding enrollment. The TDF-FTC group had higher rates of nausea (18.5% vs. 7.1%, P<0.001), vomiting (11.3% vs. 7.1%, P=0.008), and dizziness (15.1% vs. 11.0%, P=0.03) than the placebo group, but the rates of serious adverse events were similar (P=0.90). Participants who received TDF-FTC, as compared with those who received placebo, had a significant decline in bone mineral density. K65R, M184V, and A62V resistance mutations developed in 1 participant in the TDF-FTC group who had had an unrecognized acute HIV infection at enrollment. In a modified intention-to-treat analysis that included the 33 participants who became infected during the study (9 in the TDF-FTC group and 24 in the placebo group; 1.2 and 3.1 infections per 100 person-years, respectively), the efficacy of TDF-FTC was 62.2% (95% confidence interval, 21.5 to 83.4; P=0.03).

CONCLUSIONS

Daily TDF-FTC prophylaxis prevented HIV infection in sexually active heterosexual adults. The long-term safety of daily TDF-FTC prophylaxis, including the effect on bone mineral density, remains unknown. (Funded by the Centers for Disease Control and Prevention and the National Institutes of Health; TDF2 ClinicalTrials.gov number, NCT00448669.).

Treatment with neuropeptides attenuates c-fos expression in a mouse model of fetal alcohol syndrome

Fetal alcohol syndrome (FAS) is the most common nongenetic cause of mental retardation and is characterized by neurodevelopmental anomalies. C-FOS is a cellular marker of transcriptional activity in the stress-signal pathway. Previously, we showed the treatment with NAP (NAPVSIPQ) + SAL (SALLRSIPA) reversed the learning deficit after prenatal alcohol exposure in FAS. Our objective was to evaluate if the mechanism of actions of NAP + SAL involves the stress-signal pathway differentiating C-FOS expression in mouse brains after prenatal alcohol exposure. C57Bl6/J mice were treated with alcohol (0.03 mL/g) or placebo on gestational day 8. On postnatal day 40, in utero alcohol-exposed males were treated via gavage with 40 μg D-NAP and 40 μg D-SAL ( N = 6) or placebo ( N = 4); controls were gavaged with placebo daily ( N = 12). After learning evaluation, hippocampus, cerebellum, and cortex were isolated. Calibrator-normalized relative real-time polymerase chain reaction and Western blot analysis were performed. Statistics included analysis of variance and post hoc Fisher analysis. Adult treatment with NAP + SAL restored the down-regulation of C-FOS in the hippocampus after prenatal alcohol exposure ( P < 0.05), but not in the cerebellum. There was no difference in C-FOS expression in the cortex. Adult treatment with NAP + SAL restored the down-regulation of C-FOS expression in hippocampus attenuating the alcohol-induced alteration of the stress-signal pathway.

Prevention of the alcohol-induced changes in brain-derived neurotrophic factor expression using neuroprotective peptides in a model of fetal alcohol syndrome

OBJECTIVE

Our objective was to evaluate whether brain-derived neurotrophic factor (BDNF) expression is affected by prenatal alcohol exposure and whether the neuroprotective effects of the vasoactive intestinal peptide (VIP)-related peptides, NAPVSIPQ (NAP) and SALLRSIPA (SAL), are mediated through BDNF.

STUDY DESIGN

Using a well-characterized fetal alcohol syndrome (FAS) model, timed pregnant C57BL6/J mice were treated on gestational day (E) 8 with alcohol (0.03 mL/g), placebo, or alcohol plus (NAP plus SAL). Embryos were harvested at 6 hours (E8), 24 hours (E9), and 10 days (E18) and pups at postnatal day 40. Calibrator-normalized relative real time polymerase chain reaction was performed to quantify BDNF with hypoxanthine phosphoribosyl transferase-1 standardization.

RESULTS

BDNF expression was lower in the alcohol-exposed embryos than in controls at 6 hours and higher at 24 hours and 10 days (all P<.05). Pretreatment with NAP plus SAL prevented the alcohol-induced rise in BDNF expression (P<.05) at 24 hours and 10 days after alcohol exposure. We found no difference between alcohol and control in young-adults' brain (P>.05).

CONCLUSION

NAP plus SAL treatment prevented alcohol-induced changes in BDNF expression 24 hours and 10 days after alcohol exposure in mouse embryos. This may explain, at least in part, the peptides' prevention of neurodevelopmental anomalies in FAS.

Prenatal NAP+SAL prevents developmental delay in a mouse model of Down syndrome through effects on N-methyl-D-aspartic acid and gamma-aminobutyric acid receptors

OBJECTIVE

Down syndrome (DS) affects 1/800 infants. Prenatal NAPVSIPQ (NAP) and SALLRSIPA (SAL) (NAP+SAL) prevent developmental delay in Ts65Dn mice, a mouse model of DS. We investigated whether this finding involves N-methyl-D-aspartic acid and gamma-aminobutyric acid (GABA) receptor subunits.

STUDY DESIGN

Pregnant Ts65Dn mice were treated with placebo or NAP+SAL on gestational days 8-12. After developmental delay prevention was shown, 4 trisomic (Ts), 4 control, and 3 Ts+NAP+SAL adult offspring brains (from 3 litters) were collected. Calibrator-normalized real-time polymerase chain reaction was performed using primers for N-methyl-D-aspartic acid subunits NR2A and NR2B, and for GABA subunits GABA(A)alpha5 and GABA(A)beta3 with glyceraldehyde-3-phosphate dehydrogenase standardization. Statistics included analysis of variance and Fisher PLSD with P < .05 as significant.

RESULTS

NR2A, NR2B, and GABA(A)beta3 levels were decreased in Ts vs control (all P < .05). Prenatal NAP+SAL increased NR2A, NR2B, and GABA(A)beta3 to levels similar to control (all P < .05). A significant difference in GABA(A)alpha5 levels was not found.

CONCLUSION

Prenatal NAP+SAL increases NR2A, NR2B, and GABA(A)beta3 expression in adult DS mice to levels similar to controls. This may explain how NAP+SAL improve developmental milestone achievement.

Alterations in phosphorylated cyclic adenosine monophosphate response element of binding protein activity: a pathway for fetal alcohol syndrome-related neurotoxicity

OBJECTIVE

Fetal alcohol syndrome (FAS) is the leading cause of a spectrum of preventable nongenetic learning and behavioral disorders. In adult (FAS) mice, we measured phosphorylated cyclic adenosine monophosphate response element of binding protein (pCREB) staining in hippocampal subregions to evaluate a possible mechanism underlying FAS learning deficits.

STUDY DESIGN

Pregnant C57BL6/J mice were treated on gestational day 8 with alcohol or control (saline). After learning assessment, the offspring were perfused for immunohistochemistry and brain sections probed using SER 133 pCREB antibody. Relative staining density was assessed using National Institutes of Health Image software. Statistical analysis included analysis of variance with P < .05 considered significant.

RESULTS

In all hippocampal subregions, pCREB staining was greater in the control animals than in the alcohol-treated group (P < or = .0001).

CONCLUSION

In utero alcohol exposure decreased pCREB activity in hippocampal subregions of adult mice. The dentate gyrus had the most robust cumulative decrease in pCREB staining, suggesting FAS adult learning deficits may correlate to enhanced dentate gyrus neurodegeneration.

Absence of carboxypeptidase E leads to adult hippocampal neuronal degeneration and memory deficits

Molecules that govern the formation, integrity, and function of the hippocampus remain an important area of investigation. Here we show that absence of the proneuropeptide processing enzyme, carboxypeptidase E (CPE) in CPE knock-out (KO) mice had a profound effect on memory, synaptic physiology, and the cytoarchitecture of the hippocampus in these animals. Adult CPE-KO mice displayed deficits in memory consolidation as revealed by the water-maze, object preference, and social transmission of food preference tests. These mice also showed no evoked long-term potentiation. Additionally, CPE-KO mice at 4 weeks of age and older, but not at 3 weeks of age, exhibited marked degeneration specifically of the pyramidal neurons in the hippocampal CA3 region which normally expresses high levels of CPE. Immunohistochemistry revealed that the neuronal marker, NeuN, was reduced, while the glial marker, GFAP, was increased, characteristic of gliosis in the CA3 area of CPE-KO mice. Calbindin staining indicated early termination of the mossy fibers before reaching the CA1 region in these mice. Thus, absence of CPE leads to degeneration of the CA3 neurons and perturbation of the cytoarchitecture of the hippocampus. Ex vivo studies showed that overexpression of CPE in cultured hippocampal neurons protected them against H(2)O(2) oxidative-stress induced cell death. These findings taken together indicate that CPE is essential for the survival of adult hippocampal CA3 neurons to maintain normal cognitive function.

Altered expression of KIF17, a kinesin motor protein associated with NR2B trafficking, may mediate learning deficits in a Down syndrome mouse model

OBJECTIVE

Down syndrome (DS), a major cause of mental retardation, affects 1 of 800 newborns. Mouse models for Down syndrome have been studied and found to have developmental and learning deficits, including the Ts65Dn (DS) mouse model. N-methyl-D-aspartate receptor NR2B subunit enhances synaptic plasticity. The up-regulation of KIF17, a motor protein that transports NR2B to the synaptic region parallels up-regulation of synaptic NR2B. Down regulation of KIF17 reflects up-regulation of less plastic NR2A subunit. We evaluated NR2B, NR2A, and KIF17 in Ts65Dn and control mice.

STUDY DESIGN

Ts65Dn (4) and control (4) adult brains were collected; NR2A, NR2B, and KIF17 were measured by Western blot and quantified using National Institutes of Health Image software. Comparisons were made using analysis of variance, < .05 was considered significant.

RESULTS

There was a significant decrease in KIF17 (P = .04) level in Ts65Dn mice as compared with the control animals, but there were no significant differences in the levels of NR2A (P = .79) and NR2B (P = .96).

CONCLUSION

The significant decrease of KIF17 inTs65Dn animals may in part mediate cognitive defects in DS.

Blockage of VIP during mouse embryogenesis modifies adult behavior and results in permanent changes in brain chemistry

Vasoactive intestinal peptide (VIP) regulates growth and development during the early postimplantation period of mouse embryogenesis. Blockage of VIP with a VIP antagonist during this period results in growth restriction, microcephaly, and developmental delays. Similar treatment of neonatal rodents also causes developmental delays and impaired diurnal rhythms, and the adult brains of these animals exhibit neuronal dystrophy and increased VIP binding. These data suggest that blockage of VIP during the development of the nervous system can result in permanent changes to the brain. In the current study, pregnant mice were treated with a VIP antagonist during embryonic days 8 through 10. The adult male offspring were examined in tests of novelty, paired activity, and social recognition. Brain tissue was examined for several measures of chemistry and gene expression of VIP and related compounds. Glial cells from the cortex of treated newborn mice were plated with neurons and examined for VIP binding and their ability to enhance neuronal survival. Treated adult male mice exhibited increased anxiety-like behavior and deficits in social behavior. Brain tissue exhibited regionally specific changes in VIP chemistry and a trend toward increased gene expression of VIP and related compounds that reached statistical significance in the VIP receptor, VPAC-1, in the female cortex. When compared to control astrocytes, astrocytes from treated cerebral cortex produced further increases in neuronal survival with excess synaptic connections and reduced VIP binding. In conclusion, impaired VIP activity during mouse embryogenesis resulted in permanent changes to both adult brain chemistry/cell biology and behavior with aspects of autism-like social deficits.

Understanding the mechanism of learning enhancement: NMDA and GABA receptor expression

OBJECTIVE

The administration of neurotrophic peptides NAPVSIPQ (NAP) + SALLRSIPA (SAL) to aged mice resulted in significant learning enhancement. N-methyl-D-aspartate (NMDA) and gamma-aminobutyric acid (GABA) receptors are fundamental for learning because they are the major modulators of the long-term potentiation, the electrophysiologic mechanism for learning. Also, these receptors have been shown to be involved in NAP + SAL prevention of learning deficit in a mouse model for fetal alcohol syndrome, when administered prenatally during development. Our objective was to test whether NMDA and GABA receptors contribute to the learning enhancement that is induced by the peptides after adult administration.

STUDY DESIGN

Aged (14.5 months) male mice were treated for 10 consecutive days with placebo or D-NAP + D-SAL (20 microg, by gavage). At the end of the treatment, brains were harvested. Calibrator-normalized relative real-time polymerase chain reaction was performed with primers for GABA-(A)beta3, GABA-(A)alpha5, and the NMDA receptor subunits NR2A and NR2B, with GAPDH standardization. Statistical analysis included analysis of variance, with a probability value that was considered significant at <.05.

RESULTS

Five control brains and 6 brains from animals that were treated with NAP + SAL were collected. There was no difference in GABA-(A)beta3, GABA-(A)alpha5, NR2A, and NR2B subunits after adult administration of NAP + SAL, as compared with the controls (P > .05).

CONCLUSION

Postnatal treatment with NAP + SAL induced learning enhancement in aged mice with a mechanism that does not involve alteration in NMDA and GABA receptor expression. Thus, the mechanism of learning enhancement might be different for a developing fetus than an adult or in the absence of a perturbing agent.

Neuroprotective peptides prevent some alcohol-induced alteration in gamma-aminobutyric acid A-beta3, which plays a role in cleft lip and palate and learning in fetal alcohol syndrome

OBJECTIVE

Prenatal alcohol exposure affects 1 in 100 births in the United States and results in craniofacial dysmorphologic condition and learning disabilities. In a model for fetal alcohol syndrome, neuroprotective peptides prevented fetal death and learning deficits. The gamma-aminobutyric acid A (GABA) receptor subunit GABAbeta3 plays a critical role for nervous system and palate development. Our objective was to determine whether the neuropeptides prevented alcohol-induced damage through GABAbeta3.

STUDY DESIGN

With a model for fetal alcohol syndrome, timed pregnant C57B16/J mice were treated on gestational day 8 with alcohol (25% alcohol) or control (saline solution) or alcohol plus peptides NAPVSIPQ + SALLRSIPA (NAP + SAL; 20 microg). Embryos were harvested at 6 and 24 hours and 10 days after treatment. Adult males were tested for learning on the Morris water maze, and their brains were dissected. With samples from at least 3 litters per time point, calibrator-normalized relative real-time polymerase chain reaction was performed for GABAbeta3 with glyceraldehyde-3-phosphate dehydrogenase standardization. Statistical analysis included analysis of variance and Fisher protected least significant difference.

RESULTS

Twenty-four hours and 10 days after treatment, alcohol decreased GABAbeta3 in the embryos (P < or = .01); this decrease was prevented by the peptides (P = .01). GABAbeta3 was higher in alcohol treated adult brains respect to the controls (P = .002); this rise was not prevented by the peptides.

CONCLUSION

Treatment with the neuropeptides NAPVSIPQ and SALLRSIPA prevented the alcohol-induced decline in GABAbeta3 expression 10 days after alcohol exposure. Because palate formation continues through E18, NAPVSIPQ and SALLRSIPA may be beneficial for the prevention of cleft lip and palate.