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Previous studies have shown inconsistent results regarding the effect of the Val158Met polymorphism of the catechol-O-methyltransferase (COMT) gene on personality and cognition. Here, nonclinical Caucasian university students of Italian origin were administered the Temperament and Character Inventory-Revised, Tellegen Absorption Scale, Differential Attentional Processes Inventory, and Waterloo-Stanford Group Scale of Hypnotic Susceptibility. We found that the COMT Val158Met polymorphism was significantly associated with the disorderliness facet of novelty seeking (NS4) and that sex was a moderator of this association. Females with the Met/Met genotype showed higher NS4 scores compared to those with the Val/Met and Val/Val genotypes. No significant genotype effect was found for males. Additionally, we failed to find a significant effect of the COMT gene on attention and hypnotic suggestibility measures. These results provide further evidence for a sex-specific influence on the gene-behaviour associations.

It has long been known that there is decreased mitochondrial function in several tissues of Niemann–Pick C1 model mice and cultured cells. These defects contribute to the accumulation of Reactive Oxygen Species (ROS) and tissue damage. It is also well established that there is increased unesterified cholesterol, stored in late endosomes/lysosomes, in many tissues in mutant humans, mouse models, and mutant cultured cells. Using a mouse model with an NPC1 point mutation that is more typical of the most common form of the disease, and highly purified liver mitochondria, we find markedly decreased mitochondrial membrane cholesterol. This is compared to previous reports of increased mitochondrial membrane cholesterol. We also find that, although in wild-type or heterozygous mitochondria cytochrome c oxidase (COX) activity decreases with age as expected, surprisingly, COX activity in homozygous mutant mice improves with age. COX activity is less than half of wild-type amounts in young mutant mice but later reaches wild-type levels while total liver cholesterol is decreasing. Mutant mice also contain a decreased number of mitochondria that are morphologically abnormal. We suggest that the decreased mitochondrial membrane cholesterol is causative for the mitochondrial energy defects. In addition, we find that the mitochondrial stress regulator protein MNRR1 can stimulate NPC1 synthesis and is deficient in mutant mouse livers. Furthermore, the age curve of MNRR1 deficiency paralleled levels of total cholesterol. The role of such altered mitochondria in initiating the abnormal autophagy and neuroinflammation found in NPC1 mouse models is discussed.

The loss of NPC1 or NPC2 function results in cholesterol and sphingolipid dyshomeostasis that impairs developmental trajectories, predisposing the postnatal brain to the appearance of pathological signs, including progressive and stereotyped Purkinje cell loss and microgliosis. Despite increasing evidence reporting the activation of pro-inflammatory microglia as a cardinal event of NPC1 disease progression at symptomatic stages both in patients and preclinical models, how microglia cells respond to altered neurodevelopmental dynamics remains not completely understood. To gain an insight on this issue, we have characterized patterns of microglia activation in the early postnatal cerebellum and young adult olfactory bulb of the hypomorphic Npc1

Selective neuronal vulnerability is common to most degenerative disorders, including Niemann-Pick C (NPC), a rare genetic disease with altered intracellular trafficking of cholesterol. Purkinje cell dysfunction and loss are responsible for cerebellar ataxia, which is among the prevailing neurological signs of the NPC disease. In this review, we focus on some questions that are still unresolved. First, we frame the cerebellar vulnerability in the context of the extended postnatal time length by which the development of this structure is completed in mammals. In line with this thought, the much later development of cerebellar symptoms in humans is due to the later development and/or maturation of the cerebellum. Hence, the occurrence of developmental events under a protracted condition of defective intracellular cholesterol mobilization hits the functional maturation of the various cell types generating the ground of increased vulnerability. This is particularly consistent with the high cholesterol demand required for cell proliferation, migration, differentiation, and synapse formation/remodeling. Other major questions we address are why the progression of Purkinje cells loss is always from the anterior to the posterior lobes and why cerebellar defects persist in the mouse model even when genetic manipulations can lead to nearly normal survival.

Ferroptosis is an iron-dependent cell death caused by impaired glutathione metabolism, lipid peroxidation and mitochondrial failure. Emerging evidences report a role for ferroptosis in Friedreich's Ataxia (FRDA), a neurodegenerative disease caused by the decreased expression of the mitochondrial protein frataxin. Nrf2 signalling is implicated in many molecular aspects of ferroptosis, by upstream regulating glutathione homeostasis, mitochondrial function and lipid metabolism. As Nrf2 is down-regulated in FRDA, targeting Nrf2-mediated ferroptosis in FRDA may be an attractive option to counteract neurodegeneration in such disease, thus paving the way to new therapeutic opportunities. In this study, we evaluated ferroptosis hallmarks in frataxin-silenced mouse myoblasts, in hearts of a frataxin Knockin/Knockout (KIKO) mouse model, in skin fibroblasts and blood of patients, particularly focusing on ferroptosis-driven gene expression, mitochondrial impairment and lipid peroxidation. The efficacy of Nrf2 inducers to neutralize ferroptosis has been also evaluated.

The Presenilin1 (PSEN1) gene encodes the catalytic peptide of the γ-secretase complex, a key enzyme that cleaves the amyloid-β protein precursor (AβPP), to generate the amyloid-β (Aβ) peptides, involved in Alzheimer’s Disease (AD). Other substrates of the γ-secretase, such as E-cadherin and Notch1, are involved in neurodevelopment and haematopoiesis. Gene-specific DNA methylation influences PSEN1 expression in AD animal models. Here we evaluated canonical and non-canonical cytosine methylation patterns of the PSEN1 5ʹ-flanking during brain development and AD progression, in DNA extracted from the frontal cortex of AD transgenic mice (TgCRND8) and post-mortem human brain. Mapping CpG and non-CpG methylation revealed different methylation profiles in mice and humans. PSEN1 expression only correlated with DNA methylation in adult female mice. However, in post-mortem human brain, lower methylation, both at CpG and non-CpG sites, correlated closely with higher PSEN1 expression during brain development and in disease progression. PSEN1 methylation in blood DNA was significantly lower in AD patients than in controls. The present study is the first to demonstrate a temporal correlation between dynamic changes in PSEN1 CpG and non-CpG methylation patterns and mRNA expression during neurodevelopment and AD neurodegeneration. These observations were made possible by the use of an improved bisulphite methylation assay employing primers that are not biased towards non-CpG methylation. Our findings deepen the understanding of γ-secretase regulation and support the hypothesis that epigenetic changes can promote the pathophysiology of AD. Moreover, they suggest that PSEN1 DNA methylation in peripheral blood may provide a biomarker for AD.

Rosanna Parlato and Kerry Lee Tucker. "EMERGING CELLULAR STRESS SENSORS IN NEUROLOGICAL DISORDERS: CLOSING IN ON THE NUCLEOLUS AND THE PRIMARY CILIUM." iBooks.

The dyshomeostasis of intracellular cholesterol trafficking is typical of the Niemann-Pick type C (NPC) disease, a fatal inherited lysosomal storage disorder presenting with progressive neurodegeneration and visceral organ involvement. In light of the well-established relevance of cholesterol in regulating the endocannabinoid (eCB) system expression and activity, this study was aimed at elucidating whether NPC disease-related cholesterol dyshomeostasis affects the functional status of the brain eCB system. To this end, we exploited a murine model of NPC deficiency for determining changes in the expression and activity of the major molecular components of the eCB signaling, including cannabinoid type-1 and type-2 (CB1 and CB2) receptors, their ligands, N-arachidonoylethanolamine (AEA) and 2-arachidonoylglycerol (2-AG), along with their main synthesizing/inactivating enzymes. We found a robust alteration of distinct components of the eCB system in various brain regions, including the cortex, hippocampus, striatum and cerebellum, of Npc1-deficient compared to wild-type pre-symptomatic mice. Changes of the eCB component expression and activity differ from one brain structure to another, although 2-AG and AEA are consistently found to decrease and increase in each structure, respectively. The thorough biochemical characterization of the eCB system was accompanied by a behavioral characterization of Npc1-deficient mice using a number of paradigms evaluating anxiety, locomotor activity, spatial learning/memory abilities, and coping response to stressful experience. Our findings provide the first description of an early and region-specific alteration of the brain eCB system in NPC and suggest that defective eCB signaling could contribute at producing and/or worsening the neurological symptoms of this disorder.

The Npc1nih/nih-null model and the Npc1nmf164/nmf164 hypomorph models of Niemann-Pick C1 (NPC1) disease show defects in olfaction. We have tested the effects of the life-prolonging treatment hydroxypropyl-beta-cyclodextrin (HPBCD) on olfaction and neural stem cell numbers when delivered either systemically or by nasal inhalation. Using the paradigm of finding a hidden cube of food after overnight food deprivation, Npc1nih/nih homozygous mice showed a highly significant delay in finding the food compared with wild-type mice. Npc1nmf164/nmf164 homozygous mice showed an early loss of olfaction which was mildly corrected by somatic delivery of HPBCD which also increased the number of neural stem cells in the mutant but did not change the number in wild-type mice. In contrast, nasal delivery of this drug, at 1/5 the dosage used for somatic delivery, to Npc1nmf164/nmf164 mutant mice delayed loss of olfaction but the control of nasal delivered saline did so as well. The nasal delivery of HPBCD to wild-type mice caused loss of olfaction but nasal delivery of saline did not. Neural stem cell counts were not improved by nasal therapy with HPBCD. We credit the delay in olfaction found with the treatment, a delay which was also found for time of death, to a large amount of stimulation the mice received with handling during the nasal delivery.

Proteins belonging to the TGFβ-stimulated clone 22 domain (TSC22D) family display a repertoire of activities, regulating cell proliferation and differentiation. The tumor suppressor activity of the first identified member of the family, TSC22D1 (formerly named TSC-22), has been extensively studied, but afterward a longer isoform encoded by the same gene turned out to play an opposite role. We have previously characterized the role of TSC22D1 and TSC22D4 in cell differentiation using granule neurons (GNs) isolated from the mouse cerebellum. However, the possibility to study the role of these factors in cell proliferation was limited by the fact that GNs readily exit from the cell-cycle and differentiate upon isolation and in vitro culture. To overcome this limitation, we have now exploited DAOY medulloblastoma cells, which are ontogenetically similar to cerebellar GNs and can be efficiently transfected with interfering RNA for gene knockdown purposes. Our findings indicate that TSC22D4-TSC22D1 short isoform heterodimers are involved in the escape from cell proliferation and exit from the cell-cycle, whereas, the TSC22D1 long isoform is required for cell proliferation, acting independently from TSC22D4. We also show that the silencing of specific expression of TSC22D4 or TSC22D1 isoforms affects the cell-cycle progression. These findings add a novel insight on the function of TSC22D proteins, with particular reference to the tumor suppressor activity of the TSC22D1 short isoform, which is re-framed within the context of a functional interplay with TSC22D4 and the mutually exclusive expression with the TSC22D1 long isoform.

Activation of Akt/Protein Kinase B (PKB) by phosphatidylinositol-3-kinase (PI3K) controls several cellular functions largely studied in mammalian cells, including preimplantation embryos. We previously showed that early mouse embryos inherit active Akt from oocytes and that the intracellular localization of this enzyme at the two-cell stage depends on the T-cell leukemia/lymphoma 1 oncogenic protein, Tcl1. We have now investigated whether Akt isoforms, namely Akt1, Akt2 and Akt3, exert a specific role in blastomere proliferation during preimplantation embryo development. We show that, in contrast to other Akt family members, Akt2 enters male and female pronuclei of mouse preimplantation embryos at the late one-cell stage and thereafter maintains a nuclear localization during later embryo cleavage stages. Depleting one-cell embryos of single Akt family members by microinjecting Akt isoform-specific antibodies into wild-type zygotes, we observed that: (a) Akt2 is necessary for normal embryo progression through cleavage stages; and (b) the specific nuclear targeting of Akt2 in two-cell embryos depends on Tcl1. Our results indicate that preimplantation mouse embryos have a peculiar regulation of blastomere proliferation based on the activity of the Akt/PKB family member Akt2, which is mediated by the oncogenic protein Tcl1. Both Akt2 and Tcl1 are essential for early blastomere proliferation and embryo development.

Ferroptosis is an iron-dependent form of regulated cell death, arising from the accumulation of lipid-based reactive oxygen species when glutathione-dependent repair systems are compromised. Lipid peroxidation, mitochondrial impairment and iron dyshomeostasis are the hallmark of ferroptosis, which is emerging as a crucial player in neurodegeneration. This review provides an analysis of the most recent advances in ferroptosis, with a special focus on Friedreich’s Ataxia (FA), the most common autosomal recessive neurodegenerative disease, caused by reduced levels of frataxin, a mitochondrial protein involved in iron–sulfur cluster synthesis and antioxidant defenses. The hypothesis is that the iron-induced oxidative damage accumulates over time in FA, lowering the ferroptosis threshold and leading to neuronal cell death and, at last, to cardiac failure. The use of anti-ferroptosis drugs combined with treatments able to activate the antioxidant response will be of paramount importance in FA therapy, such as in many other neurodegenerative diseases triggered by oxidative stress.

Niemann-Pick Type C1 disorder (NPC) is a rare lysosomal storage disease characterized by the accumulation of cholesterol in lysosomes. NPC has no FDA approved treatments yet, however 2-hydroxypropyl-β-cyclodextrin (HPβCD) has shown efficacy for treating the disease in both mouse and feline NPC models and is currently being investigated in late stage clinical trials. Despite promising results, therapeutic use of HPβCD is limited by the need for high doses, ototoxicity and intrathecal administration. These limitations can be attributed to its poor pharmacokinetic profile. In the attempt to overcome these limitations, we have designed a β-cyclodextrin (βCD) based polymer prodrugs (ORX-301) for an enhanced pharmacokinetic and biodistribution profile, which in turn can potentially provide an improved efficacy at lower doses. We demonstrated that subcutaneously injected ORX-301 extended the mean lifespan of NPC mice at a dosage 5-fold lower (800 mg/kg, body weight) the HPβCD dose proven efficacious (4000 mg/kg). We also show that ORX-301 penetrates the blood brain barrier and counteracts neurological impairment. These properties represent a substantial improvement and appear to overcome major limitations of presently available βCD-based therapy, demonstrating that this novel prodrug is a valuable alternative/complement for existing therapies.

There is growing evidence that the complex clinical manifestations of lysosomal storage diseases (LSDs) are not fully explained by the engorgement of the endosomal-autophagic-lysosomal system. In this review, we explore current knowledge of common pathogenetic mechanisms responsible for the early onset of tissue abnormalities of two LSDs, Mucopolysaccharidosis type II (MPSII) and Niemann-Pick type C (NPC) diseases. In particular, perturbations of the homeostasis of glycosaminoglycans (GAGs) and cholesterol (Chol) in MPSII and NPC diseases, respectively, affect key biological processes, including morphogen signaling. Both GAGs and Chol finely regulate the release, reception and tissue distribution of Shh. Hence, not surprisingly, developmental processes depending on correct Shh signaling have been found altered in both diseases. Besides abnormal signaling, exaggerated activation of microglia and impairment of autophagy and mitophagy occur in both diseases, largely before the appearance of typical pathological signs.

We previously demonstrated that the nuclear form of Glutathione peroxidase 4 (nGPx4) has a peculiar distribution in sperm head, being localized to nuclear matrix and acrosome and that sperm lacking nGPx4 are more prone to decondensation in vitro. In this study we have hypothesized that sperm retained acetylated histones and nGPx4 are implicated in paternal chromatin decondensation and male pronucleus formation at fertilization. Indeed, significant higher amounts of acetylated histone H4 and acetylated histone H3 were observed by both immunofluorescence and western blotting in nGPx4-KO sperm vs WT ones. In vitro fertilization of zona pellucida-deprived oocytes by WT sperm in the presence of trichostatin (TSA) also demonstrated that paternal histone acetylation was inversely related to the timing of sperm nucleus decondensation at fertilization. In contrast, TSA had no effect on nGPx4-KO sperm, indicating they had a maximal level of histone acetylation. Moreover the paternally imprinted gene Igf2/H19 was hypomethylated in KO sperm compared to WT ones. The lack of nGPx4 negatively affected male fertility, causing a marked decrease in total pups and pregnancies with delivery, a significant reduction in pronuclei (PN) embryos in in vitro fertilization assays and an approximately 2 h delay in egg fertilization in vivo. Because the zona pellucida binding and fusion to oolemma of nGPx4-KO and WT sperm were similar, the subfertility of nGPx4 sperm reflected a decreased sperm progression through egg cumulus/zona pellucida, pinpointing a defective acrosome in line with acrosomal nGPx4 localization. We conclude that paternal acetylated histones and acrosomal nGPx4 are directly involved in fertilization.

Transcription factors operate in developmental processes to mediate inductive events and cell competence, and perturbation of their function or regulation can dramatically affect morphogenesis, organogenesis, and growth. We report that a narrow spectrum of amino-acid substitutions within the transactivation domain of the v-maf avian musculoaponeurotic fibrosarcoma oncogene homolog (MAF), a leucine zipper-containing transcription factor of the AP1 superfamily, profoundly affect development. Seven different de novo missense mutations involving conserved residues of the four GSK3 phosphorylation motifs were identified in eight unrelated individuals. The distinctive clinical phenotype, for which we propose the eponym Aymé-Gripp syndrome, is not limited to lens and eye defects as previously reported for MAF/Maf loss of function but includes sensorineural deafness, intellectual disability, seizures, brachycephaly, distinctive flat facial appearance, skeletal anomalies, mammary gland hypoplasia, and reduced growth. Disease-causing mutations were demonstrated to impair proper MAF phosphorylation, ubiquitination and proteasomal degradation, perturbed gene expression in primary skin fibroblasts, and induced neurodevelopmental defects in an in vivo model. Our findings nosologically and clinically delineate a previously poorly understood recognizable multisystem disorder, provide evidence for MAF governing a wider range of developmental programs than previously appreciated, and describe a novel instance of protein dosage effect severely perturbing development.

Recent evidence highlights the protective role of reelin against amyloid β (Aβ)-induced synaptic dysfunction and cognitive impairment in Alzheimer disease (AD). In this study, exploiting TgCRND8 mice that overexpress a mutant form of amyloid β precursor protein (AβPP) and display an early onset of AD neuropathological signs, we addressed the question whether changes of reelin expression eventually precede the appearance of Aβ-plaques in a sex-dependent manner. We show that sex-associated and brain region-specific differences in reelin expression appear long before Aβ-plaque formation. However, in spite of a downregulation of reelin expression compared to males, TgCRND8 females display fewer Aβ-plaques, suggesting that additional factors, other than sex and reelin level, influence amyloidosis in this mouse model.

In this study we show that postnatal development of cerebellar granule neurons (GNs) is defective in Npc1−/− mice. Compared to age-matched wild-type littermates, there is an accelerated disappearance of the external granule layer (EGL) in these mice. This is due to a premature exit from the cell cycle of GN precursors residing at the level of the EGL. As a consequence, the size of cerebellar lobules of these mice displays a 20%–25% reduction compared to that of age-matched wild-type mice. This size reduction is detectable at post-natal day 28 (PN28), when cerebellar GN development is completed while signs of neuronal atrophy are not yet apparent. Based on the analysis of EGL thickness and the determination of proliferating GN fractions at increasing developmental times (PN8–PN14), we trace the onset of this GN developmental defect during the second postnatal week. We also show that during this developmental time Shh transcripts undergo a significant reduction in Npc1−/− mice compared to age-matched wild-type mice. In light of the mitogenic activity of Shh on GNs, this observation further supports the presence of defective GN proliferation in Npc1−/− mice. A single injection of hydroxypropyl-β-cyclodextrin at PN7 rescues this defect, restoring the normal patterns of granule neuron proliferation and cerebellar lobule size. To our knowledge, these findings identify a novel developmental defect that was underappreciated in previous studies. This defect was probably overlooked because Npc1 loss-of-function does not affect cerebellar foliation and causes the internal granule layer and molecular layer to decrease proportionally, giving rise to a normally appearing, yet harmoniously smaller, cerebellum., Highlights • Cerebellar lobules of adult Npc1−/− mice display a 20–25% reduction in size compared to wild-type age-matched mice. • The proliferation of granule neuron (GN) precursors in the developing cerebellum of Npc1−/− mice is defective. • Npc1−/− GN precursors of the external granule layer (EGL) undergo a premature exit from the cell cycle. • The EGL of Npc1−/− mice is thinner and persists for a shorter time. • A single injection of hydroxypropyl-β-cyclodextrin at PN7 rescues these defects.

Niemann-Pick type C1 (NPC1) disease is a lysosomal storage disorder caused by defective intracellular trafficking of exogenous cholesterol. Purkinje cell (PC) degeneration is the main sign of cerebellar dysfunction in both NPC1 patients and animal models. It has been recently shown that a significant decrease in Sonic hedgehog (Shh) expression reduces the proliferative potential of granule neuron precursors in the developing cerebellum of Npc1 −/− mice. Pursuing the hypothesis that this developmental defect translates into functional impairments, we have assayed Npc1-deficient pups belonging to the milder mutant mouse strain Npc1 nmf164 for sensorimotor development from postnatal day (PN) 3 to PN21. Npc1 nmf164 / Npc1 nmf164 pups displayed a 2.5-day delay in the acquisition of complex motor abilities compared to wild-type (wt) littermates, in agreement with the significant disorganization of cerebellar cortex cytoarchitecture observed between PN11 and PN15. Compared to wt, Npc1 nmf164 homozygous mice exhibited a poorer morphological differentiation of Bergmann glia (BG), as indicated by thicker radial shafts and less elaborate reticular pattern of lateral processes. Also BG functional development was defective, as indicated by the significant reduction in GLAST and Glutamine synthetase expression. A reduced VGluT2 and GAD65 expression also indicated an overall derangement of the glutamatergic/GABAergic stimulation that PCs receive by climbing/parallel fibers and basket/stellate cells, respectively. Lastly, Npc1-deficiency also affected oligodendrocyte differentiation as indicated by the strong reduction of myelin basic protein. Two sequential 2-hydroxypropyl-β-cyclodextrin administrations at PN4 and PN7 counteract these defects, partially preventing functional impairment of BG and fully restoring the normal patterns of glutamatergic/GABAergic stimulation to PCs. These findings indicate that in Npc1 nmf164 homozygous mice the derangement of synaptic connectivity and dysmyelination during cerebellar morphogenesis largely anticipate motor deficits that are typically observed during adulthood.

Niemann-Pick type C (NPC) disease is a lysosomal storage disorder characterized by the occurrence of visceral and neurological symptoms. At present, the molecular mechanisms causing neurodegeneration in this disease are unknown. Here we report the altered expression and/or mislocalization of the TAR-DNA binding protein 43 (TDP-43) in both NPC mouse and in a human neuronal model of the disease. We also report the neuropathologic study of a NPC patient’s brain, showing that while TDP-43 is below immunohistochemical detection in nuclei of cerebellar Purkinje cells, it has a predominant localization in the cytoplasm of these cells. From a functional point of view, the TDP-43 mislocalization, that occurs in a human experimental neuronal model system, is associated with specific alterations in TDP-43 controlled genes. Most interestingly, treatment with N-Acetyl-cysteine (NAC) or beta-cyclodextrin (CD) can partially restore TDP-43 nuclear localization. Taken together, the results of these studies extend the role of TDP-43 beyond the Amyotrophic lateral sclerosis (ALS)/frontotemporal dementia (FTD)/Alzheimer disease (AD) spectrum. These findings may open novel research/therapeutic avenues for a better understanding of both NPC disease and the TDP-43 proteinopathy disease mechanism. Electronic supplementary material The online version of this article (doi:10.1186/s40478-016-0325-4) contains supplementary material, which is available to authorized users.

The lysosomal storage disorder, Niemann Pick type C1 (NPC1), presents a variable phenotype including neurovisceral and neurological symptoms. 2-Hydroxypropyl-s-cyclodextrin (HPsCD)-based therapies are presently the most promising route of intervention. While severe cerebellar dysfunction remains the main disabling feature of NPC1, sensory functions including auditory and olfactory ones are also affected. Morphological and functional anomalies of Npc1 −/− mouse retina have also been observed, although the functional integrity of the visual pathway from retina to visual cortex is still unsettled. We have addressed this issue by characterizing the visual evoked potential (VEP) response of Npc1 −/− mice and determining if/how HPsCD administration influences the VEPs of both Npc1 −/− and Npc1 +/+ mice. VEP elicited by a brief visual stimulus were recorded from the scalp overlying the visual cortex of adult (PN, postnatal days 60, 75, 85 and 100) Npc1 +/+ and Npc1 −/− mice that had received repeated injections of either HPsCD or plain vehicle. The first injection was given at PN4 and was followed by a second one at PN7 and thereafter by weekly injections up to PN49. Cholesterol accumulation and myelin loss were finally assessed by filipin staining and myelin basic protein immunohistochemistry, respectively. We have found that the transmission of visual signals from retina to visual cortex is negatively influenced by the loss of Npc1 function. In fact, the VEP response of Npc1 −/− mice displayed a highly significant increase in the latency compared to that of Npc1 +/+ mice. HPsCD administration fully rescued this defect and counteracted the cholesterol accumulation in retinal ganglion cells and dorsal lateral geniculate nucleus neurons, as well as the myelin loss in optic nerve fibers and axons projecting to the visual cortex observed in of Npc1 −/− mice. By contrast, HPsCD administration had no effect on the VEP response of Npc1 +/+ mice, further strengthening the treatment efficacy. This study pinpoints the analysis of VEP response as a potentially accurate and non-invasive approach to assess neural activity and visual information processing in NPC1 patients, as well as for monitoring the progression of the disease and assessing the efficacy of potential therapies.

Taurine (2-aminoethanesulphonic acid) is an endogenous amino acid that has a number of protective roles in most mammalian cells, including modulation of cytoplasmic calcium levels, antioxidant effects and protection against mitochondrial dysfunction and endoplasmic reticulum stress associated with neurological disorders. Thiotaurine (2-aminoethane thiosulfonate), a molecule structurally related to hypotaurine and taurine, counteracts the damaging effect of oxidants and prevents apoptosis of human neutrophils.

BACKGROUND: A reduced number of progressively motile sperm (as may occur in cases of asthenozoospermia or when cryopreserved spermatozoa are used for fertilization) limits the possibility of applying various assisted reproductive techniques (ARTs). We previously showed that incubation of sperm with the phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002 increases sperm progressive motility and enhances the number of sperm recovered by capacitation protocols used in ART. METHODS AND RESULTS: In the present study, we investigate the motilityenhancing effects of this compound in epididymal mouse sperm, and examine the use of the mouse system to investigate the effect of LY294002 on oocyte fertilization and preimplantation embryo development. Our results show that neither pre-incubation of mouse spermatozoa with the inhibitor during in vitro capacitation nor the direct addition of LY294002 to the sperm–oocyte mixture significantly affects the process of fertilization and preimplantation development of embryos produced even when they developed in the presence of LY294002. CONCLUSIONS: The present data encourage the design of new drugs based on the molecular structure of LY294002, which may open up new options for the in vitro treatment of human/animal asthenozoospermia.

We have studied the expression of Thg-1pit in developing and adult mouse brain by in situ hybridization analysis. We show that, at day 12.5 of embryo development, Thg-1pit expression is restricted to the rhombic lip, subventricular neuroepithelium/mantle zone, and lateral ganglionic eminence, namely the embryonic brain areas where granule cell precursors originate. Thereafter, Thg-1pit expression landmarks both differentiative steps and the mature function of granule/interneuron cells in several brain districts, including cerebellum, basal forebrain, olfactory bulb, and hippocampus. In the adult, Thg-1pit becomes also activated in mitral cells of olfactory bulb and in Purkinje cells of cerebellum, in concomitance with full development of the synaptic contacts that Purkinje and mitral cells establish with granule cells. We conclude that Thg-1pit is relevant to specification, proliferation/migration, differentiation, and mature function of granule/interneuron cells in different brain districts, as well as to the function of mature, but not immature, Purkinje cells and mitral cells. Developmental Dynamics 234:689–697, 2005. © 2005 Wiley-Liss, Inc.

In fertilized mouse eggs, de novo transcription of embryonic genes is first observed during the S phase of the one-cell stage. This transcription, however, is mostly limited to the male pronucleus and possibly uncoupled from translation, making the functional meaning obscure. We found that one-cell mouse embryos respond to the osmotic shock of in vitro isolation with migration of HSF1, the canonical stress activator of mammalian heat shock genes, to pronuclei and by transient transcription of the hsp70.1, but not hsp70.3 and hsp90, heat shock genes. Isolated growing dictyate oocytes also display a nuclear HSF1 localization, but, in contrast with embryos, they transcribe both hsp70.1 and hsp70.3 genes only after heat shock. Intranuclear injection of double-stranded oligodeoxyribonucleotides containing HSE, GAGA box or GC box consensus sequences, and antibodies raised to transcription factors HSF1, HSF2, Drosophila melanogaster GAGA factor, or Sp1 demonstrated that hsp70.1 transcription depends on HSF1 in both oocytes and embryos and that Sp1 is dispensable in oocytes and inhibitory in the embryos. Hsp70.1 thus represents the first endogenous gene so far identified to be physiologically activated and tightly regulated after fertilization in mammals.

We identified a novel isoform transcript, MPP alpha-2, of the mouse Mg(2+)-dependent protein phosphatase (MPP) alpha gene. The amino acid sequence encoded by MPP alpha-2 differs from the previously known MPP alpha-1 sequence only at the carboxyl terminal region. Northern and in situ hybridization analysis revealed differential expression patterns of these two transcripts in the embryo and in the adult organism, suggesting an elaborate regulation of the MPP alpha gene.

Recent evidence emphasizes the role of dysregulated one-carbon metabolism in Alzheimer’s Disease (AD). Exploiting a nutritional B-vitamin deficiency paradigm, we have previously shown that PSEN1 and BACE1 activity is modulated by one-carbon metabolism, leading to increased amyloid production. We have also demonstrated that S-adenosylmethionine (SAM) supplementation contrasted the AD-like features, induced by B-vitamin deficiency. In the present study, we expanded these observations by investigating the effects of SAM and SOD (Superoxide dismutase) association. TgCRND8 AD mice were fed either with a control or B-vitamin deficient diet, with or without oral supplementation of SAM + SOD. We measured oxidative stress by lipid peroxidation assay, PSEN1 and BACE1 expression by Real-Time Polymerase Chain Reaction (PCR), amyloid deposition by ELISA assays and immunohistochemistry. We found that SAM + SOD supplementation prevents the exacerbation of AD-like features induced by B vitamin deficiency, showing synergistic effects compared to either SAM or SOD alone. SAM + SOD supplementation also contrasts the amyloid deposition typically observed in TgCRND8 mice. Although the mechanisms underlying the beneficial effect of exogenous SOD remain to be elucidated, our findings identify that the combination of SAM + SOD could be carefully considered as co-adjuvant of current AD therapies.

Myo-inositol (myoIns) has a positive role in mammalian development and human reproduction. Since experiments on farming species suggest a similar role in preimplantation development, we evaluated the hypothesis that the inclusion of myoIns in human embryo culture media would produce an increase in embryo quality in IVF cycles, using the mouse embryo assay.To determine the effect of myoIns on completion of preimplantation development in vitro, one-cell embryos of the inbred C57BL/6N mouse strain were produced by ICSI, cultured in human fertilization media in the presence of myoIns (myoIns+) or in its absence (myoIns-) and evaluated morphologically. Daily progression through cleavage stages, blastocyst production and expansion and blastomere number at 96 hours post fertilization were assessed.Compared to myoIns- embryos, myoIns+ embryos displayed a faster cleavage rate and by the end of preimplantation development, the majority of myoIns+ blastocysts was expanded and formed by a higher number of blastomeres.The presence of myoIns resulted in both an increase in proliferation activity and developmental rate of in vitro cultured early mouse embryos, representing a substantial improvement of culture conditions. These data may identify myoIns as an important supplement for human embryo preimplantation culture.

Thg-1pit, a novel mouse gene, was detected in a screen for genes that are differentially expressed in the developing pituitary of wild-type and Lhx3 null mutant embryos. The predicted translation product of the Thg-1pit gene contains a C-terminal TSC-box adjacent to a leucine zipper motif. These features are characteristic for the TSC-22/DIP/bun family of proteins. The onset of prominent Thg-1pit expression coincides with Lhx3 activation at early stages of pituitary development. Expression is further enhanced as cells begin to differentiate within the developing pituitary gland. No expression is observed in the pituitary rudiment of mutants that lack Lhx3 function. A possible role is thus suggested for Lhx3 activities in the regulation of Thg-1pit function during early steps of pituitary organogenesis.

We have investigated the onset of zygotic genome transcription in early two-cell mouse embryos by analyzing the regulation of hsp70.1, one of the first genes expressed after fertilization. The transcriptional activation of both an episomic hsp70 promoter and the endogenous hsp70.1 gene requires the contiguity of the GC box proximal to the TATA box with a GAGA box and involves GC box- and GAGA box-binding factors. In vivo transcription factor titrations with double-stranded oligodeoxyribonucleotides and antibodies pinpoint these factors as Sp1 and a novel murine GAGA box-binding factor, which is structurally related to the Drosophila GAGA factor and acts as transcriptional coactivator/potentiator of Sp1. Mouse unfertilized eggs and one-cell and two-cell embryos display a GAGA box-binding activity of maternal origin that disappears at the four-cell stage and is also abundant in the gonads, but is barely detectable in other adult tissues. In light of the well-established nucleosome-disruption role of the Drosophila GAGA factor, these findings suggest a novel mechanism of enhancer-independent gene derepression in early mouse embryos.

TCL1 promotes blastomere proliferation through nuclear transfer, but not direct phosphorylation, of AKT/PKB in early mouse embryos

Presenilin 1 and presenilin 2 are widely expressed during brain development. Several mutations in these proteins have been associated with autosomal-dominant inherited forms of Alzheimer disease. Their expression is regulated by various cellular and extracellular factors, which change with age and sex. Both age and sex are key risk factors for Alzheimer’s disease, but the issue of whether the expression of presenilins is influenced by the sex during early postnatal development of the brain has been poorly investigated so far. In this study, we report that transcript levels of presenilins, and the subset of neurons expressing these proteins in various brain areas of the developing post-natal brain are different in male and female rats, suggesting that their function(s) may contribute to sexual dimorphism in the brain, both at morphological and functional levels.

Chronic lymphocytic leukemia (CLL) is a B-cell malignancy with a mature phenotype. In spite of its relatively indolent nature, no radical cure is as yet available. CLL is not associated with either a unique cytogenetic or a molecular defect, which might have been a potential therapeutic target. Instead, several factors are involved in disease development, such as environmental signals which interact with genetic abnormalities to promote survival, proliferation and an immune surveillance escape. Among these, PI3-Kinase signal pathway alterations are nowadays considered to be clearly important. The TCL1 gene, an AKT co-activator, is the cause of a mature T-cell leukemia, as well as being highly expressed in all B-CLL. A TCL1 transgenic mouse which reproduces leukemia with a distinct immunophenotype and similar to the course of the human B-CLL was developed several years ago and is widely used by many groups. This is a review of the CLL biology arising from work of many independent investigators who have used TCL1 transgenic mouse model focusing on pathogenetic, microenviroment and therapeutic targets.