Actions of 17β-estradiol and testosterone in the mitochondria and their implications in aging

A decline in the mitochondrial functions and aging are two closely related processes. The presence of estrogen and androgen receptors and hormone-responsive elements in the mitochondria represents the starting point for the investigation of the effects of 17β-estradiol and testosterone on the mitochondrial functions and their relationships with aging. Both steroids trigger a complex molecular mechanism that involves crosstalk between the mitochondria, nucleus, and plasma membrane, and the cytoskeleton plays a key role in these interactions. The result of this signaling is mitochondrial protection. Therefore, the molecular components of the pathways activated by the sexual steroids could represent targets for anti-aging therapies. In this review, we discuss previous studies that describe the estrogen- and testosterone-dependent actions on the mitochondrial processes implicated in aging.

Vestibular lesion-induced developmental plasticity in spinal locomotor networks during Xenopus laevis metamorphosis

During frog metamorphosis, the vestibular sensory system remains unchanged, while spinal motor networks undergo a massive restructuring associated with the transition from the larval to adult biomechanical system. We investigated in Xenopus laevis the impact of a pre- (tadpole stage) or post-metamorphosis (juvenile stage) unilateral labyrinthectomy (UL) on young adult swimming performance and underlying spinal locomotor circuitry. The acute disruptive effects on locomotion were similar in both tadpoles and juvenile frogs. However, animals that had metamorphosed with a preceding UL expressed restored swimming behavior at the juvenile stage, whereas animals lesioned after metamorphosis never recovered. Whilst kinematic and electrophysiological analyses of the propulsive system showed no significant differences in either juvenile group, a 3D biomechanical simulation suggested that an asymmetry in the dynamic control of posture during swimming could account for the behavioral restoration observed in animals that had been labyrinthectomized before metamorphosis. This hypothesis was subsequently supported by in vivo electromyography during free swimming and in vitro recordings from isolated brainstem/spinal cord preparations. Specifically, animals lesioned prior to metamorphosis at the larval stage exhibited an asymmetrical propulsion/posture coupling as a post-metamorphic young adult. This developmental alteration was accompanied by an ipsilesional decrease in propriospinal coordination that is normally established in strict left-right symmetry during metamorphosis in order to synchronize dorsal trunk muscle contractions with bilateral hindlimb extensions in the swimming adult. Our data thus suggest that a disequilibrium in descending vestibulospinal information during Xenopus metamorphosis leads to an altered assembly of adult spinal locomotor circuitry. This in turn enables an adaptive compensation for the dynamic postural asymmetry induced by the vestibular imbalance and the restoration of functionally-effective behavior.

Decrease of ATP by mitochondrial m-calpain inhibitory peptide in the rat retinas

Activations of mitochondrial calpains cause apoptosis-inducing factor-dependent apoptosis of retinal photoreceptor cells in the Royal College of Surgeons (RCS) rat, an animal model of retinitis pigmentosa. In the present study, we attempted to develop specific inhibitors of mitochondrial calpains that would prevent the retinal degeneration. We examined the inhibitory potency of 20-mer peptides of the m-calpain for mitochondrial calpains activity, determined the inhibitory regions, and conjugated the cell-penetrating peptides (CPP). The cytotoxicity and delivery of the peptide was evaluated using mouse photoreceptor-derived 661W cells. After intravitreal injection of the peptide in RCS rats, we examined the peptide delivery to the retina, photoreceptor cell death numbers, responses of the electroretinogram (ERG), concentrations of intracellular ATP, and changes of retinal morphology. Results showed that one of the peptides inhibited the activity of the mitochondrial m-calpain. The HIV-1 tat-conjugated m-calpain peptide, HIV-Nm, could preserve the inhibitory potency of the mitochondrial m-calpain, and penetrate into the 661W cells. While intravitreal injection of HIV-Nm made it possible to deliver to the retina, it did not prevent photoreceptor cell death. Furthermore, it caused the ERG attenuation and the decrease in the intracellular ATP only a day after the injection. Although HIV-Nm did not cause histological change of the retina after 1 or 2 days of the administration, the morphological abnormality of the retina was observed after 3-14 days. Our results demonstrated that HIV-Nm failed to prevent the photoreceptor cell death, but rather caused the attenuation of ERG response and the decrease of ATP.

The amygdala: an agent of change in adolescent neural networks

This article is part of a Special Issue "Puberty and Adolescence". A unique component of adolescent development is the need to master new developmental tasks in which peer interactions become primary (for the purposes of becoming autonomous from parents, forming intimate friendships, and romantic/sexual partnerships). Previously, it has been suggested that the ability to master these tasks requires an important re-organization in the relation between perceptual, motivational, affective, and cognitive systems in a very general and broad way that is fundamentally influenced by the infusion of sex hormones during pubertal development (Scherf et al., 2012). Herein, we extend this argument to suggest that the amygdala, which is vastly connected with cortical and subcortical regions and contains sex hormone receptors, may lie at the heart of this re-organization. We propose that during adolescent development there is a shift in the attribution of relevance to existing stimuli and contexts that is mediated by the amygdala (e.g., heightened relevance of peer faces, reduced relevance of physical distance from parents). As a result, amygdala inputs to existing stable neural networks are re-weighted (increased or decreased), which destabilizes the functional interactions among regions within these networks and allows for a critical restructuring of the network functional organization. This process of network re-organization enables processing of qualitatively new kinds of social information and the emergence of novel behaviors that support mastery of adolescent-specific developmental tasks.

Sensitivity differences in fish offer near-infrared vision as an adaptable evolutionary trait

Near-infrared (NIR) light constitutes an integrated part of solar radiation. The principal ability to sense NIR under laboratory conditions has previously been demonstrated in fish. The availability of NIR in aquatic habitats, and thus its potential use as a cue for distinct behaviors such as orientation and detection of prey, however, depends on physical and environmental parameters. In clear water, blue and green light represents the dominating part of the illumination. In turbid waters, in contrast, the relative content of red and NIR radiation is enhanced, due to increased scattering and absorption of short and middle range wavelengths by suspended particles and dissolved colored materials. We have studied NIR detection thresholds using a phototactic swimming assay in five fish species, which are exposed to different NIR conditions in their natural habitats. Nile and Mozambique tilapia, which inhabit waters with increased turbidity, displayed the highest spectral sensitivity, with thresholds at wavelengths above 930 nm. Zebrafish, guppy and green swordtail, which prefer clearer waters, revealed significantly lower thresholds of spectral sensitivity with 825–845 nm for green swordtail and 845–910 nm for zebrafish and guppy. The present study revealed a clear correlation between NIR sensation thresholds and availability of NIR in the natural habitats, suggesting that NIR vision, as an integral part of the whole spectrum of visual abilities, can serve as an evolutionarily adaptable trait in fish.

Birth weight correlates with size but not shape of the normal human placenta

INTRODUCTION

Studies on developmental programming rely on various measures of size and form of the human placenta. Size and form are not independent of each other and covariation patterns were not determined systematically.

METHODS

Twenty-two morphologic parameters were determined on 418 placentas from uncomplicated singleton pregnancies. We determined (i) placenta weight and birth weight, (ii) form parameters such as diameters, thickness, roundness, and eccentricity of cord insertion, and (iii) shape variability by geometric morphometry. Geometric morphometry analyzes shape variability independent of size. We define the technical terms form and shape according to the language of geometric morphometry.

RESULTS

Placenta weight correlated with birth weight. The form parameters correlated variably with placenta weight and shape. Shape variability did not correlate with birth weight and placenta weight.

DISCUSSION AND CONCLUSIONS

The correlation of placenta weight with birth weight stays a cornerstone of prenatal programming. Shape analysis shows that form parameters are hybrids of size and shape. Shape variability can be interpreted as an outcome of adaptation of a placenta to maternal factors and the associated uterine habitat. Correlation analysis of the whole data array provides a rigorous statistical frame to interpret published data and plan new studies.

Toxicity of Industrially Relevant Chlorinated Organic Solvents In Vitro

The cytotoxic effects of 4 industrially important chlorinated organic solvents, dichloromethane (DCM), 1,2-dichloroethane (DCE), trichloroethylene (TCE), and tetrachloroethylene (PERC) in vitro, were investigated. Jurkat T cells were exposed to the solvents individually for 72 hours and changes in reactive oxygen species (ROS) formation, cell proliferation, intracellular free calcium concentration ([Ca2+]), and caspase-3 activity were measured. There was a concentration-dependent increase in the ROS formation and intracellular free [Ca2+] following exposure to each of the solvents. This was accompanied by a decrease in the cell proliferation. Solvent potency decreased in the following order: PERC > TCE > DCM > DCE. Caspase-3 activity was increased in a concentration-dependent manner by TCE and PERC but was not significantly altered by DCM or DCE. n-Acetyl-l-cysteine pretreatment showed that changes in the intracellular free [Ca2+] and caspase-3 activity were independent of ROS formation. However, increased ROS formation did play a causal role in the decreased cell proliferation observed.

Simvastatin induces apoptosis and disruption of the actin cytoskeleton in human dental pulp cells and periodontal ligament fibroblasts

OBJECTIVE

Simvastatin, a competitive inhibitor of 3-hydroxy-3-methylglutaryl coenzyme A reductase, and widely used as cholesterol-lowering agent, has been suggested for its beneficial effects on alveolar bone formation, regeneration of dental pulp tissue and periodontal ligament. High doses of simvastatin appear to induce apoptosis in several cell types, but little is known about its possible effect on tooth-associated cells. Therefore, the effects of simvastatin were studied on apoptosis and cell morphology of human dental pulp cells (HDPCs) and periodontal ligament fibroblasts (HPLFs).

METHODS

HDPCs/HPLFs obtained from 4 patients were cultured with or without various concentrations of simvastatin (0.1, 1, and 10μM) for 24, 48, and 72h. The 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to evaluate cell viability. The levels of apoptosis of HDPCs and HPLFs were measured by flow cytometry after Annexin V/propidium iodide double staining. Phalloidin-FITC and 4',6-diamidino-2-phenylindole dihydrochloride (DAPI) staining was used to examine differences in the actin cytoskeleton and nuclear morphology, respectively.

RESULTS

The viability of HDPCs and HPLFs was significantly reduced after simvastatin treatment in a dose- and time-dependent manner (p<0.05). The apoptosis of HDPCs and HPLFs was significantly increased in 10μM simvastatin-treated cells (p<0.05). The effect on apoptosis was comparable for HDPCs and HPLFs. Nuclear staining showed typical apoptotic nuclear condensation and fragmentation in simvastatin-treated HDPCs/HPLFs. A dose- and time-dependent simvastatin-induced disruption of the actin cytoskeleton was observed in both cell types.

CONCLUSION

Our data demonstrated that simvastatin decreases the viability of HDPCs and HPLFs, probably by inducing apoptosis.

Microglia activation in the extremely preterm human brain

BACKGROUND

The periventricular white matter (PVWM) of the immature preterm brain is selectively vulnerable to a spectrum of injury. Although essential for normal brain development, the presence of resident microglia may exacerbate PVWM injury.

METHODS

We used immunohistochemistry to investigate microglia profile in human preterm noninjured control brains and in brains with evidence of germinal matrix hemorrhage/intraventricular hemorrhage (GMH/IVH), with median gestational age (GA) of 24.1 and 25.4 wk, respectively.

RESULTS

The number of microglia in the PVWM was higher than the other brain regions in both the control and GMH/IVH groups. Microglial density increased further in the PVWM of GMH/IVH brains, regardless of hemorrhage severity and despite normal macroscopic and imaging appearances to the PVWM. This was due to an increase in activated Iba1/CD68- and not Iba/CD45-immunopositive microglia. However, there were very few CD68/Ki67 colocalized cells, suggesting that the source of this increase may be due to a quick transformation of CD45-immunopositive hematopoietic microglia into CD68-immunopositive microglia. There was also increased apoptosis in the PVWM of all cases of GMH/IVH, with axonal injury and increased tumor necrosis factor-α (TNF-α) expression evident in the most severe cases.

CONCLUSION

Isolated GMH/IVH may influence ongoing brain development, with a significant role played by microglial activation.

Oligodendroglial alterations and the role of microglia in white matter injury: relevance to schizophrenia

Schizophrenia is a chronic and debilitating mental illness characterized by a broad range of abnormal behaviors, including delusions and hallucinations, impaired cognitive function, as well as mood disturbances and social withdrawal. Due to the heterogeneous nature of the disease, the causes of schizophrenia are very complex; its etiology is believed to involve multiple brain regions and the connections between them, and includes alterations in both gray and white matter regions. The onset of symptoms varies with age and severity, and there is some debate over a degenerative or developmental etiology. Longitudinal magnetic resonance imaging studies have detected progressive gray matter loss in the first years of disease, suggesting neurodegeneration; but there is also increasing recognition of a temporal association between clinical complications at birth and disease onset that supports a neurodevelopmental origin. Presently, neuronal abnormalities in schizophrenia are better understood than alterations in myelin-producing cells of the brain, the oligodendrocytes, which are the predominant constituents of white matter structures. Proper white matter development and its structural integrity critically impacts brain connectivity, which affects sensorimotor coordination and cognitive ability. Evidence of defective white matter growth and compromised white matter integrity has been found in individuals at high risk of psychosis, and decreased numbers of mature oligodendrocytes are detected in schizophrenia patients. Inflammatory markers, including proinflammatory cytokines and chemokines, are also associated with psychosis. A relationship between risk of psychosis, white matter defects and prenatal inflammation is being established. Animal models of perinatal brain injury are successful in producing white matter damage in the brain, typified by hypomyelination and/or dysmyelination, impaired motor coordination and prepulse inhibition of the acoustic startle reflex, recapitulating structural and functional characteristics observed in schizophrenia. In addition, elevated expression of inflammation-related genes in brain tissue and increased production of cytokines by blood cells from patients with schizophrenia indicate immunological dysfunction and abnormal inflammatory responses, which are also important underlying features in experimental models. Microglia, resident immune defenders of the central nervous system, play important roles in the development and protection of neural cells, but can contribute to injury under pathological conditions. This article discusses oligodendroglial changes in schizophrenia and focuses on microglial activity in the context of the disease, in neonatal brain injury and in various experimental models of white matter damage. These include disorders associated with premature birth, and animal models of perinatal bacterial and viral infection, oxygen deprivation (hypoxia) and excess (hyperoxia), and elevated systemic proinflammatory cytokine levels. We briefly review the effects of treatment with antipsychotic and anti-inflammatory agents in models of perinatal brain injury, and comment on the therapeutic potential of these strategies. By understanding the neurobiological basis of oligodendroglial abnormalities in schizophrenia, it is hoped that patients will benefit from the availability of targeted and more efficacious treatment options.

Oil palm phenolics confer neuroprotective effects involving cognitive and motor functions in mice

Objectives

Phenolics are important phytochemicals which have positive effects on chronic diseases, including neurodegenerative ailments. The oil palm (Elaeis guineensis) is a rich source of water-soluble phenolics. This study was carried out to discover the effects of administering oil palm phenolics (OPP) to mice, with the aim of identifying whether these compounds possess significant neuroprotective properties.

Methods

OPP was given to BALB/c mice on a normal diet as fluids for 6 weeks while the controls were given distilled water. These animals were tested in a water maze and on a rotarod weekly to assess the effects of OPP on cognitive and motor functions, respectively. Using Illumina microarrays, we further explored the brain gene expression changes caused by OPP in order to determine the molecular mechanisms involved. Real-time quantitative reverse transcription-polymerase chain reaction experiments were then carried out to validate the microarray data.

Results

We found that mice given OPP showed better cognitive function and spatial learning when tested in a water maze, and their performance also improved when tested on a rotarod, possibly due to better motor function and balance. Microarray gene expression analysis showed that these compounds up-regulated genes involved in brain development and activity, such as those under the regulation of the brain-derived neurotrophic factor. OPP also down-regulated genes involved in inflammation.

Discussion

These results suggest that the improvement of mouse cognitive and motor functions by OPP is caused by the neuroprotective and anti-inflammatory effects of the extract.

Cellular and molecular mechanisms underlie the anti-tumor activities exerted by Walterinnesia aegyptia venom combined with silica nanoparticles against multiple myeloma cancer cell types

Multiple myeloma (MM) is a clonal disease of plasma cells that remains incurable despite the advent of several novel therapeutics. In this study, we aimed to delineate the impact of snake venom extracted from Walterinnesia aegyptia (WEV) alone or in combination with silica nanoparticles (WEV+NP) on primary MM cells isolated from patients diagnosed with MM as well as on two MM cell lines, U266 and RPMI 8226. The IC₅₀ values of WEV and WEV+NP that significantly decreased MM cell viability without affecting the viability of normal peripheral mononuclear cells (PBMCs) were determined to be 25 ng/ml and 10 ng/ml, respectively. Although both WEV (25 ng/ml) and WEV+NP (10 ng/ml) decreased the CD54 surface expression without affecting the expression of CXCR4 (CXCL12 receptor) on MM cells, they significantly reduced the ability of CXC chemokine ligand 12 (CXCL12) to induce actin cytoskeleton rearrangement and the subsequent reduction in chemotaxis. It has been established that the binding of CXCL12 to its receptor CXCR4 activates multiple intracellular signal transduction pathways that regulate MM cell chemotaxis, adhesion, and proliferation. We found that WEV and WEV+NP clearly decreased the CXCL12/CXCR4-mediated activation of AKT, ERK, NFκB and Rho-A using western blot analysis; abrogated the CXCL12-mediated proliferation of MM cells using the CFSE assay; and induced apoptosis in MM cell as determined by PI/annexin V double staining followed by flow cytometry analysis. Monitoring the expression of B-cell CCL/Lymphoma 2 (Bcl-2) family members and their role in apoptosis induction after treatment with WEV or WEV+NP revealed that the combination of WEV with NP robustly decreased the expression of the anti-apoptotic effectors Bcl-2, Bcl_XL and Mcl-1; conversely increased the expression of the pro-apoptotic effectors Bak, Bax and Bim; and altered the mitochondrial membrane potential in MM cells. Taken together, our data reveal the biological effects of WEV and WEV+NP and the underlying mechanisms against myeloma cancer cells.

Influence of aging on Bmal1 and Per2 expression in extra-SCN oscillators in hamster brain

Deletion of the core clock gene, Bmal1, ablates circadian rhythms and accelerates aging, leading to cognitive deficits and tissue atrophy (e.g., skeletal muscle) (Kondratov et al., 2006, Kondratova et al., 2010). Although normal aging has been shown to attenuate Bmal1 expression in the master circadian pacemaker in the suprachiasmatic nucleus (SCN), relatively little is known about age-related changes in Bmal1 expression in other tissues, where Bmal1 may have multiple functions. This study tested the hypothesis that aging reduces Bmal1 expression in extra-SCN oscillators including brain substrates for memory and in skeletal muscle. Brains and gastrocnemius muscles were collected from young (3-5 months) and old hamsters (17-21 months) euthanized at four times of day. Bmal1 mRNA expression was determined by conducting in situ hybridization on brain sections or real-time PCR on muscle samples. The results showed age-related attenuation of Bmal1 expression in many brain regions, and included loss of diurnal rhythms in the hippocampal CA2 and CA3 subfields, but no change in muscle. In situ hybridization for Per2 mRNA was also conducted and showed age-related reduction of diurnal rhythm amplitude selectively in the hippocampal CA1 and DG subfields. In conclusion, aging has tissue-dependent effects on Bmal1 expression in extra-SCN oscillators. These finding on normal aging will provide a reference for comparing potential changes in Bmal1 and Per2 expression in age-related pathologies. In conjunction with previous reports, the results suggest the possibility that attenuation of clock gene expression in some brain regions (the hippocampus, cingulate cortex and SCN) may contribute to age-related cognitive deficits.

A double-blind placebo controlled trial of Ginkgo biloba added to risperidone in patients with autistic disorders

Ginkgo biloba has been reported to affect the neurotransmitter system and to have antioxidant properties that could impact the pathogenesis of Autism Spectrum Disorder. Based on these studies, we decided to assess the effectiveness of Ginkgo biloba extract (Ginko T.D., Tolidaru, Iran) as an adjunctive agent to risperidone in the treatment of autism. Forty-seven outpatients with a DSM-IV-TR diagnosis of autism ages between 4 and 12 years were assigned to this double blinded clinical trial and were randomly divided into two groups. One group received risperidone plus Ginko T.D and the other received risperidone plus placebo. The dose of risperidone was 1-3 mg/day and the dose of Ginko T.D. was 80 mg/day for patients under 30 kg and 120 mg/day for patients above 30 kg. Patients were assessed using Aberrant Behavior Checklist-Community (ABC-C) rating scale and the side effect check list every 2 weeks until the endpoint. None of the 5 subscales of ABC-C rating scale showed significant differences between the two groups. Incidents of side effects were not significantly different between the two groups. Adding Ginkgo biloba to risperidone did not affect the treatment outcome of ADs. Nevertheless, further observations are needed to confirm this result.

In vivo manganese-enhanced MRI and diffusion tensor imaging of developing and impaired visual brains

This study explored the feasibility of high-resolution Mn-enhanced MRI (MEMRI) and diffusion tensor imaging (DTI) for in vivo assessments of the development and reorganization of retinal and visual callosal pathways in normal neonatal rodent brains and after early postnatal visual impairments. Using MEMRI, intravitreal Mn(2+) injection into one eye resulted in maximal T1-weighted hyperintensity in neonatal contralateral superior colliculus (SC) 8 hours after administration, whereas in adult contralateral SC signal increase continued at 1 day post-injection. Notably, mild but significant Mn(2+) enhancement was observed in the ipsilateral SC in normal neonatal rats, and in adult rats after neonatal monocular enucleation (ME) but not in normal adult rats. Upon intracortical Mn(2+) injection to the visual cortex, neonatal binocularly-enucleated (BE) rats showed an enhancement of a larger projection area, via the splenium of corpus callosum to the V1/V2 transition zone of the contralateral hemisphere in comparison to normal rats. For DTI, the retinal pathways projected from the enucleated eyes possessed lower fractional anisotropy (FA) 6 weeks after BE and ME. Interestingly, in the optic nerve projected from the remaining eye in ME rats a significantly higher FA was observed compared to normal rats. The results of this study are potentially important for understanding the axonal transport, microstructural reorganization and functional activities in the living visual brain during early postnatal development and plasticity in a global and longitudinal setting.

Effects of a water-soluble curcumin protein conjugate vs. pure curcumin in a diabetic model of erectile dysfunction

INTRODUCTION

Curcumin is involved in erectile signaling via elevation of cyclic guanosine monophosphate (cGMP).

AIM

Assessment of the effects of water-soluble curcumin in erectile dysfunction (ED).

METHODS

One hundred twenty male white albino rats were divided into: 1st and 2nd control groups with or without administration of Zinc protoporphyrin (ZnPP), 3rd and 4th diabetic groups with or without ZnPP, 5th diabetic group on single oral dose of pure curcumin, 6th diabetic group on pure curcumin administered daily for 12 weeks, 7th and 8th diabetic groups on single dose of water-soluble curcumin administered with or without ZnPP, 9th and 10th diabetic groups on water-soluble curcumin administered daily for 12 weeks with or without ZnPP. All curcumin dosage schedules were administered after induction of diabetes.

MAIN OUTCOME MEASURES

Quantitative gene expression of endothelial nitric oxide synthase (eNOS), neuronal NOS (nNOS), inducible NOS (iNOS), heme oxygenase-1 (HO-1), nuclear transcription factor-erythroid2 (Nrf2), NF-Кβ, and p38. Cavernous tissue levels of HO and NOS enzyme activities, cGMP and intracavernosal pressure (ICP).

RESULTS

Twelve weeks after induction of diabetes, ED was confirmed by the significant decrease in ICP. There was a significant decrease in cGMP, NOS, HO enzymes, a significant decrease in eNOS, nNOS, HO-1 genes and a significant elevation of NF-Кβ, p38, iNOS genes. Administration of pure curcumin or its water-soluble conjugate led to a significant elevation in ICP, cGMP levels, a significant increase in HO-1 and NOS enzymes, a significant increase in eNOS, nNOS, HO-1, and Nrf2 genes, and a significant decrease in NF-Кβ, p38, and iNOS genes. Water-soluble curcumin showed significant superiority and more prolonged duration of action. Repeated doses regimens were superior to single dose regimen. Administration of ZnPP significantly reduced HO enzyme, cGMP, ICP/ mean arterial pressure (MAP), HO-1 genes in diabetic groups.

CONCLUSION

Water-soluble curcumin could enhance erectile function with more effectiveness and with more prolonged duration of action.

Transcriptome analysis of amoeboid and ramified microglia isolated from the corpus callosum of rat brain

Background

Microglia, the resident immune cells of the central nervous system (CNS), have two distinct phenotypes in the developing brain: amoeboid form, known to be amoeboid microglial cells (AMC) and ramified form, known to be ramified microglial cells (RMC). The AMC are characterized by being proliferative, phagocytic and migratory whereas the RMC are quiescent and exhibit a slow turnover rate. The AMC transform into RMC with advancing age, and this transformation is indicative of the gradual shift in the microglial functions. Both AMC and RMC respond to CNS inflammation, and they become hypertrophic when activated by trauma, infection or neurodegenerative stimuli. The molecular mechanisms and functional significance of morphological transformation of microglia during normal development and in disease conditions is not clear. It is hypothesized that AMC and RMC are functionally regulated by a specific set of genes encoding various signaling molecules and transcription factors.

Results

To address this, we carried out cDNA microarray analysis using lectin-labeled AMC and RMC isolated from frozen tissue sections of the corpus callosum of 5-day and 4-week old rat brain respectively, by laser capture microdissection. The global gene expression profiles of both microglial phenotypes were compared and the differentially expressed genes in AMC and RMC were clustered based on their functional annotations. This genome wide comparative analysis identified genes that are specific to AMC and RMC.

Conclusions

The novel and specific molecules identified from the trancriptome explains the quiescent state functioning of microglia in its two distinct morphological states.

A comparative review of cell culture systems for the study of microglial biology in Alzheimer's disease

Over the past two decades, it has become increasingly apparent that Alzheimer’s disease neuropathology is characterized by activated microglia (brain resident macrophages) as well as the classic features of amyloid plaques and neurofibrillary tangles. The intricacy of microglial biology has also become apparent, leading to a heightened research interest in this particular cell type. Over the years a number of different microglial cell culturing techniques have been developed to study either primary mammalian microglia, or immortalized cell lines. Each microglial system has advantages and disadvantages and should be selected for its appropriateness in a particular research context. This review summarizes several of the most common microglial cell culture systems currently being employed in Alzheimer’s research including primary microglia; BV2 and N9 retroviral immortalized microglia; human immortalized microglia (HMO6); and spontaneously immortalized rodent microglial lines (EOC lines and HAPI cells). Particularities of cell culture requirements and characteristics of microglial behavior, especially in response to applied inflammogen stimuli, are compared and discussed across these cell types.

Ultrastructure of the distal retina of the adult zebrafish, Danio rerio

The organization, morphological characteristics, and synaptic structure of photoreceptors in the adult zebrafish retina were studied using light and electron microscopy. Adult photoreceptors show a typical ordered tier arrangement with rods easily distinguished from cones based on outer segment (OS) morphology. Both rods and cones contain mitochondria within the inner segments (IS), including the large, electron-dense megamitochondria previously described (Kim et al.) Four major ultrastructural differences were observed between zebrafish rods and cones: (1) the membranes of cone lamellar disks showed a wider variety of relationships to the plasma membrane than those of rods, (2) cone pedicles typically had multiple synaptic ribbons, while rod spherules had 1-2 ribbons, (3) synaptic ribbons in rod spherules were ∼2 times longer than ribbons in cone pedicles, and (4) rod spherules had a more electron-dense cytoplasm than cone pedicles. Examination of photoreceptor terminals identified four synaptic relationships at cone pedicles: (1) invaginating contacts postsynaptic to cone ribbons forming dyad, triad, and quadrad synapses, (2) presumed gap junctions connecting adjacent postsynaptic processes invaginating into cone terminals, (3) basal junctions away from synaptic ribbons, and (4) gap junctions between adjacent photoreceptor terminals. More vitread and slightly farther removed from photoreceptor terminals, extracellular microtubule-like structures were identified in association with presumed horizontal cell processes in the OPL. These findings, the first to document the ultrastructure of the distal retina in adult zebrafish, indicate that zebrafish photoreceptors have many characteristics similar to other species, further supporting the use of zebrafish as a model for the vertebrate visual system.

Apigenin induces apoptosis via extrinsic pathway, inducing p53 and inhibiting STAT3 and NFκB signaling in HER2-overexpressing breast cancer cells

Phytoestrogens are known to prevent tumor induction. But their molecular mechanisms of action are still unknown. This study aimed to examine the effect of apigenin on proliferation and apoptosis in HER2-expressing breast cancer cells. In our experiments, apigenin inhibited the proliferation of MCF-7 vec and MCF-7 HER2 cells. This growth inhibition was accompanied with an increase of sub G(0)/G(1) apoptotic fractions. Overexpression of HER2 did not confer resistance to apigenin in MCF-7 cells. Apigenin-induced extrinsic apoptosis pathway up-regulating the levels of cleaved caspase-8, and inducing the cleavage of poly (ADP-ribose) polymerase, whereas apigenin did not induce apoptosis via intrinsic mitochondrial apoptosis pathway since this compound did not decrease mitochondrial membrane potential maintaining red fluorescence and did not affect the levels of B-cell lymphoma 2 (BCL2) and Bcl-2-associated X protein. Moreover, apigenin reduced the tyrosine phosphorylation of HER2 (phospho-HER2 level) in MCF-7 HER2 cells, and up-regulated the levels of p53, phospho-p53 and p21 in MCF-7 vec and MCF-7 HER2 cells. This suggests that apigenin induces apoptosis through p53-dependent pathway. Apigenin also reduced the expression of phospho-JAK1 and phospho-STAT3 and decreased STAT3-dependent luciferase reporter gene activity in MCF-7 vec and MCF-7 HER2 cells. Apigenin decreased the phosphorylation level of IκBα in the cytosol, and abrogated the nuclear translocation of p65 within the nucleus suggesting that it blocks the activation of NFκB signaling pathway in MCF-7 vec and MCF-7 HER2 cells. Our study indicates that apigenin could be a potential useful compound to prevent or treat HER2-overexpressing breast cancer.

SOX2 hypomorphism disrupts development of the prechordal floor and optic cup

Haploinsufficiency for the HMG-box transcription factor SOX2 results in abnormalities of the human ventral forebrain and its derivative structures. These defects include anophthalmia (absence of eye), microphthalmia (small eye) and hypothalamic hamartoma (HH), an overgrowth of the ventral hypothalamus. To determine how Sox2 deficiency affects the morphogenesis of the ventral diencephalon and eye, we generated a Sox2 allelic series (Sox2(IR), Sox2(LP), and Sox2(EGFP)), allowing for the generation of mice that express germline hypomorphic levels (<40%) of SOX2 protein and that faithfully recapitulate SOX2 haploinsufficient human phenotypes. We find that Sox2 hypomorphism significantly disrupts the development of the posterior hypothalamus, resulting in an ectopic protuberance of the prechordal floor, an upregulation of Shh signaling, and abnormal hypothalamic patterning. In the anterior diencephalon, both the optic stalks and optic cups (OC) of Sox2 hypomorphic (Sox2(HYP)) embryos are malformed. Furthermore, Sox2(HYP) eyes exhibit a loss of neural potential and coloboma, a common phenotype in SOX2 haploinsufficient humans that has not been described in a mouse model of SOX2 deficiency. These results establish for the first time that germline Sox2 hypomorphism disrupts the morphogenesis and patterning of the hypothalamus, optic stalk, and the early OC, establishing a model of the development of the abnormalities that are observed in SOX2 haploinsufficient humans.

Development of active controlled retrieval during middle childhood

The aim of this study was to examine the development of active controlled memory retrieval in children. Active retrieval is an effortful retrieval required to disambiguate information stored in memory. Brain imaging studies and monkey experiments have shown that the ventrolateral prefrontal cortex (VLPFC) is specifically engaged in this retrieval in both adult humans and monkeys. Three groups of 6-, 8-, and 11-year-old children and adults were tested on an active retrieval task. Results showed a marked difference in performance between 6-year olds, who made more errors and had longer response time, and 8- and 11-year olds, who had performance similar to adults. These results provide evidence that the VLPFC and the network supporting its top-down modulation undergo substantial maturational changes between 6 and 8 years old, giving children better active control of visual memory.

Microglial reaction in axonal crossroads is a hallmark of noncystic periventricular white matter injury in very preterm infants

Disabilities after brain injury in very preterm infants have mainly been attributed to noncystic periventricular white matter injury (PWMI). We analyzed spatiotemporal patterns of PWMI in the brains of 18 very preterm infants (25-29 postconceptional weeks [pcw]), 7 preterm infants (30-34 pcw), and 10 preterm controls without PWMI. In very preterm infants, we examined PWMI in detail in 2 axonal crossroad areas in the frontal lobe: C1 (lateral to the lateral angle of the anterior horn of the lateral ventricle, at the exit of the internal capsule radiations) and C2 (above the corpus callosum and dorsal angle of the anterior horn). These brains had greater microglia-macrophage densities and activation but lesser astroglial reaction (glial fibrillary acidic protein and monocarboxylate transporter 1 expression) than in preterm cases with PWMI. In preterm infants, scattered necrotic foci were rimmed by axonal spheroids and ionized calcium binding adaptor molecule 1-positive macrophages. Diffuse lesions near these foci consisted primarily of hypertrophic and reactive astrocytes associated with fewer microglia. No differences in Olig2-positive preoligodendrocytes between noncystic PWMI and control cases were found. These data show that the growing axonal crossroad areas are highly vulnerable to PWMI in very preterm infants and highlight differences in glial activation patterns between very preterm and preterm infants.

Dangguijakyak-san protects dopamine neurons against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity under postmenopausal conditions

Dangguijakyak-san protects dopamine neurons against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced neurotoxicity under postmenopausal conditions.

ETHNOPHARMACOLOGICAL RELEVANCE

Dangguijakyak-san (DJS), a famous traditional herbal formula, has long been used to treat gynecological disorders, including postmenopausal symptoms. This study evaluated the effects and mechanism of DJS on 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity in a postmenopausal mouse model induced by ovariectomy.

MATERIALS AND METHODS

Three weeks after ovariectomy, C57bl/6 female mice were divided randomly into (1) control, (2) MPTP (30 mg/kg/day, i.p., 5 days), (3) MPTP+estrogen (50 μg/kg/day, i.p., 5 days), and (4) MPTP+DJS (50 mg/kg/day, p.o., 5 days) groups. We investigated the behavioral recovery and dopamine neuron protection of DJS using the pole test and tyrosine hydroxylase (TH) immunohistochemistry. We also explored the mechanism by assessing the protein expression of Bax, Bcl-2, cytochrome c, and cleaved caspase-3.

RESULTS

DJS treatment restored the movement behavior impaired by MPTP, showing a similar or better effect than estrogen. DJS protected TH-immunoreactive cells and fibers in the nigrostriatal region from MPTP toxicity. In addition, DJS inhibited the Bcl-2 decrease and Bax increase in mitochondria, cytochrome c release to the cytosol, and caspase-3 activation induced by MPTP.

CONCLUSIONS

DJS showed behavior recovery and dopamine neuron protection against MPTP-induced toxicity via anti-apoptotic activities in ovariectomized female mice. These results suggest that DJS treatment is effective for postmenopausal neurodegenerative diseases.

Digital cranial endocast of Hyopsodus (Mammalia, "Condylarthra"): a case of paleogene terrestrial echolocation?

We here describe the endocranial cast of the Eocene archaic ungulate Hyopsodus lepidus AMNH 143783 (Bridgerian, North America) reconstructed from X-ray computed microtomography data. This represents the first complete cranial endocast known for Hyopsodontinae. The Hyopsodus endocast is compared to other known "condylarthran" endocasts, i. e. those of Pleuraspidotherium (Pleuraspidotheriidae), Arctocyon (Arctocyonidae), Meniscotherium (Meniscotheriidae), Phenacodus (Phenacodontidae), as well as to basal perissodactyls (Hyracotherium) and artiodactyls (Cebochoerus, Homacodon). Hyopsodus presents one of the highest encephalization quotients of archaic ungulates and shows an "advanced version" of the basal ungulate brain pattern, with a mosaic of archaic characters such as large olfactory bulbs, weak ventral expansion of the neopallium, and absence of neopallium fissuration, as well as more specialized ones such as the relative reduction of the cerebellum compared to cerebrum or the enlargement of the inferior colliculus. As in other archaic ungulates, Hyopsodus midbrain exposure is important, but it exhibits a dorsally protruding largely developed inferior colliculus, a feature unique among "Condylarthra". A potential correlation between the development of the inferior colliculus in Hyopsodus and the use of terrestrial echolocation as observed in extant tenrecs and shrews is discussed. The detailed analysis of the overall morphology of the postcranial skeleton of Hyopsodus indicates a nimble, fast moving animal that likely lived in burrows. This would be compatible with terrestrial echolocation used by the animal to investigate subterranean habitat and/or to minimize predation during nocturnal exploration of the environment.

Microglia in the developing brain: a potential target with lifetime effects

Microglia are a heterogenous group of monocyte-derived cells serving multiple roles within the brain, many of which are associated with immune and macrophage like properties. These cells are known to serve a critical role during brain injury and to maintain homeostasis; yet, their defined roles during development have yet to be elucidated. Microglial actions appear to influence events associated with neuronal proliferation and differentiation during development, as well as, contribute to processes associated with the removal of dying neurons or cellular debris and management of synaptic connections. These long-lived cells display changes during injury and with aging that are critical to the maintenance of the neuronal environment over the lifespan of the organism. These processes may be altered by changes in the colonization of the brain or by inflammatory events during development. This review addresses the role of microglia during brain development, both structurally and functionally, as well as the inherent vulnerability of the developing nervous system. A framework is presented considering microglia as a critical nervous system-specific cell that can influence multiple aspects of brain development (e.g., vascularization, synaptogenesis, and myelination) and have a long term impact on the functional vulnerability of the nervous system to a subsequent insult, whether environmental, physical, age-related, or disease-related.

Sensing BMP pathway activity by immune detection of phosphorylated R-Smad proteins in mouse embryonic kidney

At the onset of mammalian kidney development, the ureteric bud invades the surrounding metanephric mesenchyme, and genetic studies in the mouse have shown that BMP pathway activity has to be antagonized in the vicinity of the epithelium, a task performed by the secreted BMP antagonist Grem1. Here, we describe a short protocol that allows for detection of the pattern of BMP canonical signal transduction by using antibodies that specifically recognize the phosphorylated forms of R-Smad proteins (Smad1, Smad5, and Smad8), which provides a way to monitor overall pathway activity in the mammalian embryonic kidney.

Fetal surgery for myelomeningocele: progress and perspectives

Myelomeningocele (MMC), one of the most common congenital malformations, can result in severe lifelong disabilities, including paraplegia, hydrocephalus, Chiari II malformation, bowel and bladder dysfunction, skeletal deformations, and neurocognitive impairment. Experimental studies provide compelling evidence that the neurological deficits associated with MMC are not simply caused by incomplete neurulation but rather by the prolonged exposure of the vulnerable neural elements to the intrauterine environment. MMC is the first non-lethal anomaly considered for fetal surgical intervention, necessitating a careful analysis of risks and benefits. Retrospective and prospective randomized studies suggest that fetal surgery of MMC before 26 weeks of gestation may preserve neuromotor function, reverse hindbrain herniation, and reduce the need for ventriculoperitoneal shunting. However, these studies also demonstrate that fetal surgery is associated with significant maternal and fetal risks. Consequently, additional research is necessary to further elucidate the pathophysiology of MMC, to define the ideal timing and technique of fetal closure, and to evaluate the long-term implications of prenatal intervention.

In ovo thyroxine exposure alters later UVS cone loss in juvenile rainbow trout

Thyroid hormones (THs) play a vital role in vertebrate neural development, and, together with the beta isoform of the thyroid hormone receptor (TRβ), the development and differentiation of cone photoreceptors in the vertebrate retina. Rainbow trout undergo a natural process of cone cell degeneration during development and this change in photoreceptor distribution is regulated by thyroxine (T4; a thyroid hormone). In an effort to further understand the role of T4 in photoreceptor ontogeny and later developmental changes in photoreceptor subtype distribution, the influence of enhanced in ovo T4 content on the onset of opsin expression and cone development was examined. Juvenile trout reared from the initial in ovo-treated embryos were challenged with exogenous T4 at the parr stage of development to determine if altered embryonic exposure to yolk THs would affect later T4-induced short-wavelength-sensitive (SWS1) opsin transcript downregulation and ultraviolet-sensitive (UVS) cone loss. In ovo TH manipulation led to upregulation of both SWS1 and long-wavelength-sensitive (LWS) opsin transcripts in the pre-hatch rainbow trout retina and to changes in the relative expression of TRβ. After 7 days of exposure to T4, juveniles that were also treated with T4 in ovo had greatly reduced SWS1 expression levels and premature loss of UVS cones relative to T4-treated juveniles raised from untreated eggs. These results suggest that changes in egg TH levels can have significant consequences much later in development, particularly in the retina.

Nurse-Enhanced Memory Intervention in Heart Failure: the MEMOIR study

BACKGROUND

Many patients with heart failure (HF) have cognitive deficits, including memory loss.

OBJECTIVES

The aim of this study was to evaluate the efficacy of a cognitive training intervention on memory (primary outcome), working memory, psychomotor speed, executive function, and performance of cognitive activities and instrumental activities of daily living (IADLs).

METHODS AND RESULTS

Forty patients with HF were randomly assigned to the computerized plasticity-based cognitive training intervention called Brain Fitness or to the health education active control intervention. Advanced practice nurses made weekly home visits to assess symptoms and monitor intervention adherence. Patients completed demographic and clinical data (baseline), neuropsychologic tests (baseline and 8 and 12 weeks), and measures of cognitive and IADLs performance (baseline and 12 weeks) and satisfaction (12 weeks). Linear mixed models analyses indicated a significant group by time interaction for delayed recall memory (P = .032) and a significant time effect for total (list learning) (P < .001) and delayed (P = .015) recall memory, psychomotor speed (P = .029), and performance of IADLs (P = .006). Intervention adherence and patient satisfaction were high.

CONCLUSIONS

To our knowledge, this was the first test of Brain Fitness in HF. Although it was a preliminary study with limitations, results support the need for a larger randomized controlled trial to determine whether the memory loss of HF is amenable to plasticity-based interventions.

Contribution of the caspase gene sequence diversification to the specifically antiviral defense in invertebrate

Vertebrates achieve adaptive immunity of all sorts against pathogens through the diversification of antibodies. However the mechanism of invertebrates' innate immune defense against various pathogens remains largely unknown. Our study used shrimp and white spot syndrome virus (WSSV) to show that PjCaspase, a caspase gene of shrimp that is crucial in apoptosis, possessed gene sequence diversity. At present, the role of gene sequence diversity in immunity has not been characterized. To address this issue, we compared the PjCaspase gene sequence diversities from WSSV-free and WSSV-resistant shrimp. The sequence analysis indicated that the PjCaspase gene from the WSSV-resistant shrimp contained a special fragment, designated as fragment 3 (221-229 aa). Down-regulation or overexpression of the PjCaspase gene containing fragment 3 led to significant inhibition or enhancement of virus-induced apoptosis, but had no effect on bacterium challenge. We found evidence that the silencing or overexpression of this gene led to a 7-fold increase or 11-fold decrease of WSSV copies, respectively. Our results suggested that the PjCaspase gene containing fragment 3 provided the molecular basis for the antiviral defense of shrimp. This study represented the first report of the role of gene sequence diversity in the immunity of an invertebrate against virus infection. Invertebrates may employ this gene sequence diversity as a system to avoid pathogen interference with their immune response.

Preschool neurobehavioral outcome following fetal myelomeningocele surgery

OBJECTIVE

It was the aim of this study to assess the prevalence of preschool neurobehavioral problems in children following fetal myelomeningocele (fMMC) surgery.

METHODS

Prior to the Management of Myelomeningocele Study, 30 fMMC patients underwent a standardized neurodevelopmental examination at 5 years of age. The prevalence of behavioral problems was assessed by the Child Behavior Check List (CBCL), which includes a total problem score and 2 broad-band indices (internalizing and externalizing problems). fMMC children were classified as having normal, at-risk or clinically significant scores based on calculated T scores.

RESULTS

Twenty-two (73%) fMMC families completed the evaluation. Mean age at delivery following fMMC surgery was 35.5 ± 1.6 weeks. The prevalence of 'at-risk' or 'clinically significant' scores for internalizing, externalizing and total behavioral problems was similar to general population norms. No difference in overall internalizing (p = 0.19), externalizing (p = 0.54) and total behavioral (p = 0.18) scores was found between non-shunted and shunted fMMC children. However, shunted fMMC children were more likely to experience anxiety and depressive (p = 0.02), pervasive developmental (p = 0.03) and withdrawn (p = 0.06) behavior. Oppositional defiant, attention deficit and hyperactivity problems were not found. No correlation was found between overall neurodevelopmental outcome and abnormal CBCL scores.

CONCLUSIONS

fMMC surgery and subsequent preterm delivery is not associated with increased behavioral problems, impaired social interactions and restricted behavior patterns. Shunted fMMC children were more likely to have scores in the 'at-risk' or 'clinically significant' range for multiple CBCL subindices. Early detection of behavioral problems following fMMC surgery provides an opportunity for targeted and timely intervention enabling affected fMMC children to be socially successful.

Analysis of the sacral neural crest cell contribution to the hindgut enteric nervous system in the mouse embryo

BACKGROUND & AIMS

The majority of the enteric nervous system is derived from the vagal neural crest, with a second contribution, which is restricted to the post-umbilical gut, originating from the sacral neural crest. In mammals, although sacral neural crest cells (NCCs) have been shown to enter the hindgut, information on their development and role remains scant. Our aim was to determine the migratory routes of sacral NCCs to the hindgut, their timing and site of entry into the gut, and their migratory behaviors and differentiation within the hindgut.

METHODS

We used in situ cell labeling, whole embryo culture, immunofluorescence, organotypic culture, and time-lapse live-cell imaging in mouse embryos.

RESULTS

Sacral NCCs emigrated from the neural tube at embryonic day 9.5, accumulated bilateral to the hindgut to form prospective pelvic ganglia at embryonic day 11.5, and from there entered the distal hindgut through its ventrolateral side at embryonic day 13.5. They then migrated along nerve fibers extending from the pelvic ganglia toward the proximal hindgut, intermingling with rostrocaudally migrating vagal NCCs to differentiate into neurons and glia. In organotypic culture, genetically labeled sacral and vagal NCCs displayed different capabilities of entering the hindgut, implying differences in their intrinsic migratory properties. Time-lapse live-cell imaging on explants ex vivo showed that sacral NCCs migrated along nerve fibers and exhibited different migratory behaviors from vagal NCCs.

CONCLUSIONS

Murine sacral NCCs are a distinct group of cells that migrate along defined pathways from neural tube to hindgut. They exhibit discrete migratory behaviors within the gut mesenchyme and contribute neurons and glial cells to the hindgut enteric nervous system.

Anti-diabetic activity and potential mechanism of total flavonoids of Selaginella tamariscina (Beauv.) Spring in rats induced by high fat diet and low dose STZ

AIM OF THE STUDY

To evaluate the anti-diabetic effects of the total flavonoids of Selaginella tamariscina (Beauv.) Spring (TFST), and to explore the pertinent mechanism.

MATERIALS AND METHODS

High fat diet and STZ (35 mg/kg) induced diabetic rats were administered with TFST at graded oral doses (100, 200 and 400mg/kg/day, ig.) for 8 weeks. A range of parameters, including blood glucose and lipid, serum insulin and glucagon, glucose tolerance, were tested to evaluate its anti-diabetic effects. The determination of protein expression of peroxisome proliferator activated receptor γ (PPAR-γ) in adipose tissue and insulin receptor substrate 1 (IRS-1) in hepatic and skeletal muscle tissues was used to study the mechanism of TFST. Moreover, the preliminary study of TFST on the antioxidant activity was performed.

RESULTS

The TFST possessed anti-diabetic activities as shown by the decreased serum levels of fast blood glucose (FBG), glycosylated hemoglobulin A1C (HbA1c), triglyceride (TG), total cholesterol (TC), free fatty acid (FFA), low density lipoprotein-cholesterol (LDL-C) and glucagon, as well as increased serum levels of high density lipoprotein-cholesterol (HDL-C), insulin and C-peptide. TFST also improved the oral glucose tolerance test (OGTT) to a certain degree. Furthermore, TFST increased the protein expression of PPAR-γ in adipose tissue, and increased the protein expressions of IRS-1 in hepatic and skeletal muscle tissues. These benefits were associated with increased superoxide dismutase (SOD) and decreased malondialdehyde (MDA) in serum.

CONCLUSIONS

TFST exert beneficial effects on hyperglycosemia and hyperlipoidemia in diabetic rats possibly through regulating the levers of PPAR-γ in adipose tissue and IRS-1 in hepatic and skeletal muscle tissues.

Induction of apoptotic cell death by ursolic acid through mitochondrial death pathway and extrinsic death receptor pathway in MDA-MB-231 cells

Ursolic acid (3-hydroxy-urs-12-en-28-oic acid) is a pentacyclic triterpenoid derived from leaves, berries, fruits, and flowers of medicinal plants, such as Rosemarinus officinalis. Ursolic acid has been shown to inhibit tumorigenesis, tumor promotion, and suppress angiogenesis. In our present study, we found that ursolic acid decreased cell proliferation rate and induce apoptosis in human breast cancer cell line, MDA-MB-231. When we checked the expression levels of proteins associated with apoptosis signal by using immunoblotting, we found that ursolic acid induces various apoptotic molecules related to either extrinsic or intrinsic apoptosis signal pathway in MDA-MB-231 cells. In our study, we found that ursolic acid induced the appearance of Fas receptor and cleavage of caspase-8, -3 and PARP. We also found that ursolic acid induced Bax up-regulation and Bcl-2 down-regulation and release of cytochrome C to the cytosol from mitochondria. Moreover, ursolic acid cleaved caspase-9 and decreased mitochondrial membrane potential (ΔΨm) as shown with JC-1 staining. These data indicate that ursolic acid induce apoptosis through both mitochondrial death pathway and extrinsic death receptor dependent pathway in MDA-MB-231 cells. Our data clearly indicate that ursolic acid could be used as a potential anticancer drug for breast cancer.

The period of the somite segmentation clock is sensitive to Notch activity

The number of vertebrae is defined strictly for a given species and depends on the number of somites, which are the earliest metameric structures that form in development. Somites are formed by sequential segmentation. The periodicity of somite segmentation is orchestrated by the synchronous oscillation of gene expression in the presomitic mesoderm (PSM), termed the "somite segmentation clock," in which Notch signaling plays a crucial role. Here we show that the clock period is sensitive to Notch activity, which is fine-tuned by its feedback regulator, Notch-regulated ankyrin repeat protein (Nrarp), and that Nrarp is essential for forming the proper number and morphology of axial skeleton components. Null-mutant mice for Nrarp have fewer vertebrae and have defective morphologies. Notch activity is enhanced in the PSM of the Nrarp(-/-) embryo, where the ~2-h segmentation period is extended by 5 min, thereby forming fewer somites and their resultant vertebrae. Reduced Notch activity partially rescues the Nrarp(-/-) phenotype in the number of somites, but not in morphology. Therefore we propose that the period of the somite segmentation clock is sensitive to Notch activity and that Nrarp plays essential roles in the morphology of vertebrae and ribs.

Isolation and characterisation of novel antioxidant constituents of Croton zambesicus leaf extract

A 1,1-diphenyl-2-picrylhydrazyl (DPPH)-activity-directed fractionation was used to target antioxidant constituents of the ethyl acetate fraction obtained from a 20% aqueous methanol crude extract of Croton zambesicus leaf. Repeated column chromatography of the fraction on silica gel and Sephadex LH-20 led to the isolation of a new natural product, identified as quercetin-3-O-β-6″(p-coumaroyl) glucopyranoside-3'-methyl ether, helichrysoside-3'-methyl ether (1), along with kaempferol-3-O-β-6″(p-coumaroyl) glucopyranoside, tiliroside (2) and apigenin-6-C-glucoside, isovitexin (3) as the antioxidant constituents. The structures of the isolated compounds were elucidated using spectroscopic techniques, namely NMR (1D and 2D) and mass spectrometry. Compounds 1 and 2 are reported from this species for the first time. In the qualitative antioxidant assay, the three isolated compounds instantly bleached the DPPH (0.2% MeOH) purple colour indicating antioxidant activity. In the quantitative antioxidant assay, all the isolated compounds demonstrated weak antioxidant activity compared to quercetin and rutin used as positive control antioxidant agents. The compounds displayed little to no cytotoxicity against Vero cells in an in vitro assay. The presence of these antioxidant compounds in the leaf extract of C. zambesicus could provide a rationale for the ethnomedicinal use of the plant in the management of oxidative-stress-related diseases in folk medicine.

Molecular cloning and characterisation of the rock bream, Oplegnathus fasciatus, Fas (CD95/APO-1), and its expression analysis in response to bacterial or viral infection

Fas belongs to the tumour necrosis factor (TNF) receptor superfamily and can transmit a death signal leading to apoptosis. In the present study, we isolated the full-length cDNA for rock bream (Oplegnathus fasciatus) Fas (RbFas). The full-length RbFas cDNA was 1770 bp long and contained an open reading frame of 957 bp that encoded 319 amino acid residues with a predicted molecular mass of 35.1 kDa. The 319 amino-acid predicted RbFas sequence is homologous to other Fas sequences, contains three cysteine-rich domains and a death domain (DD) and two potential N-glycosylation sites. Expression of RbFas mRNA was detected in nine different tissues from healthy rock bream and was the highest in red blood cells. In analyses of mitogen-stimulated RbFas expression in peripheral blood leucocytes, expression of RbFas mRNA was observed between 1 and 36 h after stimulation with LPS, and 1 and 3 h stimulation with poly I:C. In the case of bacterial injection, the RbFas transcript peaked 6 h after injection in both the kidney and the spleen. Otherwise, the RbFas transcript peaked after 1 h in spleen and 6 h in kidney following injection with RSIV.

Fetal myelomeningocele surgery: preschool functional status using the Functional Independence Measure for children (WeeFIM)

OBJECTIVE

To study preschool functional status in children following fetal myelomeningocele (fMMC) surgery.

MATERIAL AND METHODS

Prior to the NICHD-MOMS trial, 30 fMMC underwent standardized neurodevelopmental examination at 5 years of age. Functional status was determined with the Functional Independence Measure (WeeFIM), which assesses self-care, mobility, and cognitive independence.

RESULTS

Evaluations were completed in 26 (87%). Mean cognitive (93.0 ± 21.9), self-care (66.5 ± 23.9), mobility (82.3 ± 19.5), and total (77.9 ± 20.3) functional quotient of fMMC children were significantly lower than age-matched population norms (P < 0.01). Complete caregiver independence was achieved by 22 (84%), 10 (38%), 16 (62%), and 15 (58%) fMMC children for cognition, self-care, mobility, and total functional outcome, respectively. Cognitive, mobility, and total independence were higher in non-shunted than shunted fMMC children (P = 0.02, P = 0.02, and P < 0.01, respectively) and in fMMC children with average neurodevelopmental scores (P < 0.001, P = 0.01, and P < 0.01, respectively). Self-care independence tended to be higher in the non-shunted group and in fMMC children with normal neurodevelopmental outcome (P = 0.07 and P = 0.09, respectively).

CONCLUSION

The majority of fMMC children achieved cognitive and mobility independence, but continue to require significant assistance in self-care. Non-shunted and fMMC children with normal neurodevelopmental outcome were more likely to be independent in daily living activities. Better understanding of the extent of functional limitations following fMMC surgery will allow for more effective early interventions geared toward maximizing independence in everyday tasks in all environments.

Deregulated miR-155 promotes Fas-mediated apoptosis in human intervertebral disc degeneration by targeting FADD and caspase-3

The role of apoptosis in the pathogenesis of intervertebral disc degeneration (IDD) remains enigmatic. Accumulating evidence has shown that the apoptotic machinery is regulated by miRNAs. We hypothesized that miRNAs might contribute to apoptosis in IDD. We have found that 29 miRNAs were differentially expressed and miR-155 was down-regulated in degenerative nucleus pulposus (NP). The deregulation of miR-155 was further verified using real-time PCR (0.56 fold, p < 0.05). Bioinformatics target prediction identified FADD and caspase-3 as putative targets of miR-155. Furthermore, miR-155 inhibited FADD and caspase-3 expression by directly targeting their 3'-UTRs, which was abolished by mutation of the miR-155 binding sites. In vitro up-regulation of miR-155 in human NP cells by transfection with lentiviral pre-miR-155 resulted in repression of FADD and caspase-3; whereas knockdown of miR-155 with lentiviral antigomiR-155 led to over-expression of FADD and caspase-3. Also, Fas-mediated apoptosis was increased when antagonizing miR-155 and decreased when using pre-miR-155 in human NP cells. In addition, we presented direct evidence of NP cells undergoing apoptosis in IDD tissues using transmission electron microscopy analysis. Moreover, a combination of in situ hybridization (ISH) and immunohistochemistry (IHC) revealed that miR-155 expressed in the cytoplasm of human NP cells with reverse correlation with FADD and caspase-3. In summary, this is the first study addressing the underlying mechanisms of IDD in terms of apoptosis and miRNAs. Furthermore, caspase-3 is identified as a novel target of miR-155. Our results suggest that deregulated miR-155 promotes Fas-mediated apoptosis in human IDD by targeting FADD and caspase-3, implicating an aetiological and therapeutic role of miR-155 in IDD.

Altered temporal patterns of anxiety in aged and amyloid precursor protein (APP) transgenic mice

Both normal aging and dementia are associated with dysregulation of the biological clock, which contributes to disrupted circadian organization of physiology and behavior. Diminished circadian organization in conjunction with the loss of cholinergic input to the cortex likely contributes to impaired cognition and behavior. One especially notable and relatively common circadian disturbance among the aged is "sundowning syndrome," which is characterized by exacerbated anxiety, agitation, locomotor activity, and delirium during the hours before bedtime. Sundowning has been reported in both dementia patients and cognitively intact elderly individuals living in institutions; however, little is known about temporal patterns in anxiety and agitation, and the neurobiological basis of these rhythms remains unspecified. In the present study, we explored the diurnal pattern of anxiety-like behavior in aged and amyloid precursor protein (APP) transgenic mice. We then attempted to treat the observed behavioral disturbances in the aged mice using chronic nightly melatonin treatment. Finally, we tested the hypothesis that time-of-day differences in acetylcholinesterase and choline acetyltransferase expression and general neuronal activation (i.e., c-Fos expression) coincide with the behavioral symptoms. Our results show a temporal pattern of anxiety-like behavior that emerges in elderly mice. This behavioral pattern coincides with elevated locomotor activity relative to adult mice near the end of the dark phase, and with time-dependent changes in basal forebrain acetylcholinesterase expression. Transgenic APP mice show a similar behavioral phenomenon that is not observed among age-matched wild-type mice. These results may have useful applications to the study and treatment of age- and dementia-related circadian behavioral disturbances, namely, sundowning syndrome.

Monoamine oxidase a expression is vital for embryonic brain development by modulating developmental apoptosis

Monoamine oxidases (MAO-A, MAO-B) metabolize biogenic amines and have been implicated in neuronal apoptosis. Although apoptosis is an important process in embryo development, the role of MAO isoenzymes has not been investigated in detail. We found that expression of MAO-A and MAO-B can be detected early on during embryo development. Expression levels remained constant until around midgestation but then dropped to almost undetectable levels toward birth. Similar expression kinetics were observed in the brain. Isoform-specific expression silencing of MAO-A mediated by siRNA during in vitro embryogenesis induced developmental defects, as indicated by a reduction of the crown rump length and impaired cerebral development. These alterations were paralleled by elevated serotonin levels. Similar abnormalities were observed when embryos were cultured in the presence of the MAO-A inhibitor clorgyline or when the transcriptional inhibitor of MAO-A expression R1 was overexpressed. In contrast, no such alterations were detected when expression of MAO-B was knocked down. To explore the underlying mechanisms for the developmental abnormalities in MAO-A knockdown embryos, we quantified the degree of developmental apoptosis in the developing brain. MAO-A knockdown reduced the number of apoptotic cells in the neuroepithelium, which coincided with impaired activation of caspases 3 and 9. Moreover, we observed reduced cyclin D1 levels as an indicator of impaired cell proliferation in MAO-A knockdown embryos. This data highlights MAO-A as a vital regulator of embryonic brain development.

The Zagreb Collection of human brains: a unique, versatile, but underexploited resource for the neuroscience community

The Zagreb Collection of developing and adult human brains was founded in 1974 by Ivica Kostović and consists of 1,278 developing and adult human brains, including 610 fetal, 317 children, and 359 adult brains. It is one of the largest collections of developing human brains. The collection serves as a key resource for many focused research projects and has led to several seminal contributions on mammalian cortical development, such as the discovery of the transient fetal subplate zone and of early bilaminar synaptogenesis in the embryonic and fetal human cerebral cortex, and the first description of growing afferent pathways in the human fetal telencephalon. The Zagreb Collection also serves as a core resource for ever-growing networks of international collaboration and represents the starting point for many young investigators who now pursue independent research careers at leading international institutions. The Zagreb Collection, however, remains underexploited owing to a lack of adequate funding in Croatia. Funding could establish an online catalog of the collection and modern virtual microscopy scanning methods to make the collection internationally more accessible.

Animal models of periventricular leukomalacia

Periventricular leukomalacia, specifically characterized as white matter injury, in neonates is strongly associated with the damage of pre-myelinating oligodendrocytes. Clinical data suggest that hypoxia-ischemia during delivery and intrauterine or neonatal infection-inflammation are important factors in the etiology of periventricular leukomalacia including cerebral palsy, a serious case exhibiting neurobehavioral deficits of periventricular leukomalacia. In order to explore the pathophysiological mechanisms of white matter injury and to better understand how infectious agents may affect the vulnerability of the immature brain to injury, novel animal models have been developed using hypoperfusion, microbes or bacterial products (lipopolysaccharide) and excitotoxins. Such efforts have developed rat models that produce predominantly white matter lesions by adopting combined hypoxia-ischemia technique on postnatal days 1-7, in which unilateral or bilateral carotid arteries of animals are occluded (ischemia) followed by 1-2 hour exposure to 6-8% oxygen environment (hypoxia). Furthermore, low doses of lipopolysaccharide that by themselves have no adverse-effects in 7-day-old rats, dramatically increase brain injury to hypoxic-ischemic challenge, implying that inflammation sensitizes the immature central nervous system. Therefore, among numerous models of periventricular leukomalacia, combination of hypoxia-ischemia-lipopolysaccharide might be one of the most-acceptable rodent models to induce extensive white matter injury and ensuing neurobehavioral deficits for the evaluation of candidate therapeutics.

Enhancement of shrimp antiviral immune response through caspase-dependent apoptosis by small molecules

Epidemic diseases cost large amount of economic loss in the shrimp aquaculture. To control the epidemic diseases, it is a very efficient approach to enhance the shrimp immunity by immunostimulants. In aquaculture, however, the applications of the available immunostimulants are very limited due to the lack of information about the roles of these immunostimulants in animal immunity. In the present study, a caspase protein (PjCaspase), required in shrimp antiviral apoptosis, was used as the target protein to screen for small molecules which would enhance the shrimp immunity. Based on screening using the EGFP-PjCaspase fusion protein in insect cells, four small molecules could enhance the activity of PjCaspase protein. Among them, IL-2 and evodiamine were further evidenced to enhance the apoptotic activity of shrimp hemocytes in vivo, suggesting that the small molecules improved the activity of apoptosis through the activation of the PjCaspase protein. The results indicated that the enhancement of apoptotic activity effectively inhibited the white spot syndrome virus (WSSV) infection in shrimp, which further led to the decrease of mortalities of WSSV-infected shrimp. Therefore, our study, for the first time, presented that the strategy using the key proteins in immune responses of aquatic organisms as the target proteins was a very efficient approach for the screening of immunostimulants to prevent the aquatic organisms from pathogen infections.