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SINGAPORE – NUS Study Uncovers Novel Genetic Alterations Contributing to Development of Leukaemia.

AUSTRALIA – Meat Consumption Contributing to Global Obesity.

AUSTRALIA – Warmer Climate Could Lower Dengue Risk.

UNITED KINGDOM – Treatment Option for Alzheimer’s Disease Possible.

UNITED STATES – Hot News Flash! Menopause, Sleepless Nights Make Women’s Bodies Age Faster.

UNITED STATES – Innovative Technology Improves Detection of Bladder Cancer.

UNITED STATES – Research Shows New Neurons Created Through Exercise Don’t Cause You to Forget Old Memories.

INDIA – Praj to be the First Indian Technology Provider to Launch ‘Green Fund’ for 2G Ethanol Projects.

MALAYSIA – Tunku Laksamana Johor Cancer Foundation Partners Singapore-based Asian American Medical Group to Conduct Feasibility of Establishing Centre of Excellence in Southern Malaysia to Treat Cancer.

TAIWAN – Curcumin Derivatives May Prevent Alzheimer’s Disease by Promoting Amyloid-β Clearance.

The separation of input patterns received from the entorhinal cortex (EC) by the dentate gyrus (DG) is a well-known critical step of information processing in the hippocampus. Although the role of interneurons in separation pattern efficiency of the DG has been theoretically known, the balance of neurogenesis of excitatory neurons and interneurons as well as its potential role in information processing in the DG is not fully understood. In this work, we study separation efficiency of the DG for different rates of neurogenesis of interneurons and excitatory neurons using a novel computational model in which we assume an increase in the synaptic efficacy between excitatory neurons and interneurons and then its decay over time. Information processing in the EC and DG was simulated as information flow in a two layer feed-forward neural network. The neurogenesis rate was modeled as the percentage of new born neurons added to the neuronal population in each time bin. The results show an important role of an optimal neurogenesis rate of interneurons and excitatory neurons in the DG in efficient separation of inputs from the EC in pattern separation tasks. The model predicts that any deviation of the optimal values of neurogenesis rates leads to different decreased levels of the separation deficits of the DG which influences its function to encode memory.

Sequencing of complete nuclear genomes of Neanderthal and Denisovan stimulated studies about their relationship with modern humans demonstrating, in particular, that DNA alleles from both Neanderthal and Denisovan genomes are present in genomes of modern humans. The Papuan genome is a unique object because it contains both Neanderthal and Denisovan alleles. Here, we have shown that the Papuan genomes contain different gene functional groups inherited from each of the ancient people. The Papuan genomes demonstrate a relative prevalence of Neanderthal alleles in genes responsible for the regulation of transcription and neurogenesis. The enrichment of specific functional groups with Denisovan alleles is less pronounced; these groups are responsible for bone and tissue remodeling. This analysis shows that introgression of alleles from Neanderthals and Denisovans to Papuans occurred independently and retention of these alleles may carry specific adaptive advantages.

Brain-derived neurotrophic factor (BDNF), a crucial member of the neurotrophic family, is most widely distributed and extensively studied in the mammalian central nervous system. Accumulating evidence from animal and human studies indicates that BDNF plays critical roles in regulating neurogenesis, synaptogenesis and plasticity, and neurological diseases. In this review, we summarize the synthesis and general signaling pathway of BDNF and review its pivotal roles in neurogenesis and the maintenance of axon and dendrites, synaptic transmission and plasticity, which are thought to be the cellular basis for learning and memory, and certain neurological diseases, including Alzheimer’s disease, Parkinson’s disease and Huntington’s disease. Future studies should focus on understanding the multifunctional roles of BDNF in different brain regions and tightly controlled clinical studies.

Postnatal hippocampal neurogenesis originates from progenitor cells in the postnatal dentate gyrus (DG) and results in new granule cell neuron. Neurogenesis in the DG of the hippocampus undergoes several developmental stages. Stem cells/early progenitor cells with their cell bodies located within the subgranular zone in the dentate gyrus have radial processes that project through the granular cell layer and short tangential processes that extend along the border of the granule cell layer and the hilus. These cells give rise to late progenitor cells, which are thought to divide to produce intermediate stage progenitors, which then undergo further rounds of cell division to generate post-mitotic immature granule neurons. Pax6 transcription factor is a key player for patterning the brain and promoting embryonic neurogenesis. Recently, we have found that Pax6 is expressed differentially during the neurogenesis of hippocampus. Pax6 is expressed in stem cells/early progenitor cells and late progenitor cells. We have also found that cell proliferation was 30% decreased at postnatal stages and that the number of stem cells/early progenitors decreased in Pax6 deficient rSey²/+ rat. Taken all together, Pax6 is suggested to maintain the stem cells/early progenitor cells and to regulate their proliferation and differentiation.

In the adult brain, neurogenesis continues to take place in certain regions including the subventricular zone (SVZ) and the subgranular zone (SGZ) of the hippocampal dentate gyrus (DG). Pax6 is a transcriptional factor that plays key roles in critical events of the developing central nervous system such as brain patterning and neurogenesis, and also expressed in the SGZ. In order to reveal whether Pax6 had the role in the regulation of adult neurogenesis, we have studied the proliferative activity and character of Pax6-expressing cells in the adult DG using immunohistochemistry. Here we have shown that a majority of Pax6-expressing cells in the SGZ exhibited a progenitor-like character. In Pax6 mutant Sey/+ mouse, cell proliferation was markedly decreased at postnatal stages. These results suggest that Pax6 have critical roles in the postnatal hippocampal neurogenesis.

To produce precise number of neurons and glial cells from neuroepithelial cells, the progeression and exit of the cell cycle should accurately be coordinated. In mammalian neuroepithelial cells, the molecular and cellular mechanisms coordinating the cell cycle progression and neuronal differentiation is yet unknown. Recently, we noticed that a certain cell cycle regulator protein localized in the basal endfeet of the mouse neuroepithelial cells. However, it is difficult to know in which cell cycle phase the protein localizes, because suitable cell cycle markers expressed at the endfeet of the neuroepithelial cells are missing. To address this issue, we performed sequential labeling of neuroepithelial cells by introducing EGFP-F cDNA into cultured mouse embryos using electroporation and short pulse labeling of S-phase cells by incorporating BrdU, and analyzed the cell cycle phase of EGFP-F labeled cells by using antibodies to BrdU and PH3 (a M-phase marker). We found that EGFP-F-labled cells were in S-phase to Gl-phase, but not in G2-phase to M-phase 6 hours after electroporation, and that both of the nucleus and the whole outline of neuroepithelial cell including bipolar processes were clearly visualized. These results suggest that our labeling strategy makes it possible to characterize the cell cycle of neuroepithelial cells, and therefore the cell cycle-dependent distribution of cytoplasmic proteins at the endfeet would be elucidated in the future.