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Pathological conditions such as epilepsy cause misregulation of adult neural stem/progenitor populations in the adult hippocampus in mice, and the resulting abnormal neurogenesis leads to impairment in learning and memory. However, how animals cope with abnormal neurogenesis remains unknown. Here we show that microglia in the mouse hippocampus attenuate convulsive seizure-mediated aberrant neurogenesis through the activation of Toll-like receptor 9 (TLR9), an innate immune sensor known to recognize microbial DNA and trigger inflammatory responses. We found that microglia sense self-DNA from degenerating neurons following seizure, and secrete tumour necrosis factor-a, resulting in attenuation of aberrant neurogenesis. Furthermore, TLR9 deficiency exacerbated seizure-induced cognitive decline and recurrent seizure severity. Our findings thus suggest the existence of bidirectional communication between the innate immune and nervous systems for the maintenance of adult brain integrity.

By affected sib-pair linkage analysis of 24 families with pre-eclampsia, we confirm a susceptibility locus on chromosome 10q22.1 in Dutch females: a multipoint non-parametric linkage score of 3.6 near marker D10S1432 was obtained. Haplotype analysis showed a parent-of-origin effect: maximal allele sharing in the affected sibs was found for maternally derived alleles in all families, but not for the paternally derived alleles. As matrilineal inheritance suggests the presence of maternally expressed imprinted genes, while imprinting operates predominantly in (extra)embryonic tissues, all genes (n=132) known on 10q22 between GATA121A08 and D10S580 were screened for seven sequence-related features associated with imprinting and subsequently tested for expression in first trimester placenta. Placental expression of genes selected in this way (n=55) was compared with expression in androgenetic placentas of identical gestational age. Two regions on 10q22 were identified with developmentally co-repressed genes with non-random chromosomal distribution. Interestingly, these two clusters, near CTNNA3 and KCNMA1 and each containing five genes with down-regulated expression in androgenetic placentas, coincided with the regions with maximal maternal allele sharing seen in the pre-eclamptic sisters. Our linkage and expression data are compatible with the concept that pre-eclampsia involves maternally expressed imprinted genes that operate in the first trimester placenta.

SummaryCurrently, all methods for converting non-neuronal cells into neurons involve injury to the brain; however, whether neuronal transdifferentiation can occur long after the period of insult remains largely unknown. Here, we use the transcription factor NEUROD1, previously shown to convert reactive glial cells to neurons in the cortex, to determine whether astrocyte-to-neuron transdifferentiation can occur under physiological conditions. We utilized adeno-associated virus 9 (AAV9), which crosses the blood-brain barrier without injury, to deliver NEUROD1 to astrocytes through an intravascular route. Interestingly, we found that a small, but significant number of non-reactive astrocytes converted to neurons in the striatum, but not the cortex. Moreover, astrocytes cultured to minimize their proliferative potential also exhibited limited neuronal transdifferentiation with NEUROD1 expression. Our results show that a single transcription factor can induce astrocyte-to-neuron conversion under physiological conditions, potentially facilitating future clinical approaches long after the acute injury phase.

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Previous observations indicate that transfer of human chromosome (chr.) 1 induces senescence of endometrial cancer cells. To identify the gene(s) responsible for the senescence, we first analyzed the structural integrity of the introduced chr. 1 in immortal revertant from chr.1-transferred HHUA cells. The data demonstrated a correlation between nonrandom deletions within the 1q31-qter region and reversion to immortality. Next, by using a panel of 12 microsatellite markers, we found high frequencies of loss of heterozygosity in the particular 1q region (1q41-42), in surgically removed samples. Then, we screened the genetic mutation of the genes involved in this region, with endometrial cancer panel. Among them, EGLN1, that is a member of prolyl hydroxylase and can facilitate HIF-1 degradation by ubiquitination through the hydroxylation of HIF-1, was mutated at significantly higher frequencies (12/20, 60%). Introduction of wild-type EGLN1 into endometrial cancer cell lines (HHUA, Ishikawa and HWCA), that carry EGLN1 gene mutations induced senescence. This was invoked through the negative regulation of HIF-1 expression. In addition, alternative way of negative regulation of HIF-1 by Factor inhibiting HIF-1(FIH), SiRNA against HIF-1, and HIF-1 inhibitor, YC-1, could also induce senescence. Thus, EGLN1 can be considered as a candidate tumor suppressor on chr. 1q, and our observation could open the new aspect in exploring the machinery of senescence induction associated with HIF-1 signal transduction. These results also suggested the availability of negative regulation of HIF-1 signals for uterine cancer treatment, especially for uterine sarcomas that have worse prognosis and show a high frequency of EGLN1 gene abnormality. ' 2005 Wiley-Liss, Inc.Key words: HIF-1; EGLN1; endometrial cancer; prolyl hydroxylase; Chromosome 1Endometrial cancer is one of the most common gynecologic malignancies. Considerable evidence has suggested a number of genetic events associated with this tumor. However, the molecular pathogenesis of endometrial cancers remains poorly understood. Genetic alterations that represent gross chromosomal alterations are known to occur during endometrial carcinogenesis. Among them, nonrandom chromosome changes have been found in almost 80% of endometrial cancers and are consistent with rearrangements and deletion in a centromeric or paracentromeric area, leading to an excess of chromosome (chr.) 1q.1-3 Previously, we transferred a single human chromosome into endometrial cancer cells (HHUA and Ishikawa cells) via microcell fusion to investigate the role of chr.1 alterations in the carcinogenesis. As a result, we found that the tumorigenicity of microcell hybrid clones with an introduced chr.1, 6, or 9 is completely suppressed. However, the hybrids with an introduced chr.1 differed from those with an introduced chr. 6 or 9.4,5 A large proportion of the hybrids with chr. 1 had arrested cell growth and showed remarkable alterations in cell morphology. This finding is in contrast with the transfer of chr. 6 ...

Together with residual host neurons, transplanted neural stem cell (NSC)-derived neurons play a critical role in reconstructing disrupted neural circuits after spinal cord injury (SCI). Since a large number of tracts are disrupted and the majority of host neurons die around the lesion site as the damage spreads, minimizing this spreading and preserving the lesion site are important for attaining further improvements in reconstruction. High mobility group box-1 (HMGB1) is a damage-associated molecular pattern protein that triggers sterile inflammation after tissue injury. In the ischemic and injured brain, neutralization of HMGB1 with a specific antibody reportedly stabilizes the blood-brain barrier, suppresses inflammatory cytokine expression, and improves functional recovery. Using a SCI model mouse, we here developed a combinatorial treatment for SCI: administering anti-HMGB1 antibody prior to transplantation of NSCs derived from human induced pluripotent stem cells (hiPSC-NSCs) yielded a dramatic improvement in locomotion recovery after SCI. Even anti-HMGB1 antibody treatment alone alleviated blood-spinal cord barrier disruption and edema formation, and increased the number of neurites from spared axons and the survival of host neurons, resulting in functional recovery. However, this recovery was greatly enhanced by the subsequent hiPSC-NSC transplantation, reaching an extent that has never before been reported. We also found that this improved recovery was directly associated with connections established between surviving host neurons and transplant-derived neurons. Taken together, our results highlight combinatorial treatment with anti-HMGB1 antibody and hiPSC-NSC transplantation as a promising novel therapy for SCI. Stem Cells 2018;36:737-750.

We demonstrated here the growth-suppressing effects of sodium butyrate (NaB) on human endometrial and ovarian cancer cells. The arrest of cells at the G1 checkpoint accounted for this effect. NaB-mediated p21 might arrest endometrial and ovarian cancer cells at the G0/G1 phase by eliciting pRb unphosphorylation. To demonstrate the role of pRb regulation by p21, we measured the sensitivity to NaB of cervical cancer cells in which pRb had been inactivated by HPV E7. The cervical cancer cells displayed a sensitivity in NaB-mediated G2/M arrest in addition to their sensitivity in G0/G1 arrest. Arrest at G0/G1 and G2/M accompanied induction of senescence-like phenotypes (SLPs). Most importantly, the effect of NaB on senescence induction was not coupled with the predominance of hypophosphorylated pRb forms in the cervical cancer cells. This suggested that NaB had the potential to elicit SLPs through p21-mediated withdrawal from cell cycle progression. The consequences of p21 induction were manifold. The effects of NaB on gynecologic cancer cell growth indicated its potential use in cancer treatment. NaB was effective even in the cancer cells with mutant p53 and/or Rb genes by eliciting cell senescence.