Involvement of an Aberrant Vascular System in Neurodevelopmental, Neuropsychiatric, and Neuro-Degenerative Diseases

The vascular system of the prenatal brain is crucial for the development of the central nervous system. Communication between vessels and neural cells is bidirectional, and dysfunctional communication can lead to neurodevelopmental diseases. In the present review, we introduce neurodevelopmental and neuropsychiatric diseases potentially caused by disturbances in the neurovascular system and discuss candidate genes responsible for neurovascular system impairments. In contrast to diseases that can manifest during the developing stage, we have also summarized the disturbances of the neurovascular system in neurodegenerative diseases including Alzheimer's disease and Parkinson's disease. Furthermore, we discussed the role of abnormal vascularization and dysfunctional vessels in the development of neurovascular-related diseases.

Bronchiolar adenoma/ciliated muconodular papillary tumor mixed with adenocarcinoma in situ in the same tumor

Bronchiolar adenoma (BA)/ciliated muconodular papillary tumor (CMPT) is defined as a benign tumor composed of epithelial and basal cells. Recently, some cases with driver mutations or malignant transformation have been observed. Thus, whether BA/CMPT is benign or malignant remains controversial. We herein report an extremely rare case of a 68-year-old woman with a CMPT accompanied by adenocarcinoma in situ (AIS). BA/CMPT existed inside the AIS. The BA/CMPT component did not show any driver mutations; however, the AIS component had an EGFR driver mutation in exon 19. The accumulation of cases and further studies are needed to discuss the malignant potential of BA/CMPT.

Essential Roles of Exocyst Complex Component 3-like 2 on Cardiovascular Development in Mice

Angiogenesis is a process to generate new blood vessels from pre-existing vessels and to maintain vessels, and plays critical roles in normal development and disease. However, the molecular mechanisms underlying angiogenesis are not fully understood. This study examined the roles of exocyst complex component (Exoc) 3-like 2 (Exoc3l2) during development in mice. We found that Exoc3l1, Exoc3l2, Exoc3l3 and Exoc3l4 are expressed abundantly in endothelial cells at embryonic day 8.5. The generation of Exoc3l2 knock-out (KO) mice showed that disruption of Exoc3l2 resulted in lethal in utero. Substantial numbers of Exoc3l2 KO embryos exhibited hemorrhaging. Deletion of Exoc3l2 using Tie2-Cre transgenic mice demonstrated that Exoc3l2 in hematopoietic and endothelial lineages was responsible for the phenotype. Taken together, these findings reveal that Exoc3l2 is essential for cardiovascular and brain development in mice.

Extracellular Environment-Controlled Angiogenesis, and Potential Application for Peripheral Nerve Regeneration

Endothelial cells acquire different phenotypes to establish functional vascular networks. Vascular endothelial growth factor (VEGF) signaling induces endothelial proliferation, migration, and survival to regulate vascular development, which leads to the construction of a vascular plexuses with a regular morphology. The spatiotemporal localization of angiogenic factors and the extracellular matrix play fundamental roles in ensuring the proper regulation of angiogenesis. This review article highlights how and what kinds of extracellular environmental molecules regulate angiogenesis. Close interactions between the vascular and neural systems involve shared molecular mechanisms to coordinate developmental and regenerative processes. This review article focuses on current knowledge about the roles of angiogenesis in peripheral nerve regeneration and the latest therapeutic strategies for the treatment of peripheral nerve injury.

Nasal spindle cell tumor with rhabdomyoblastic features: A rare and diagnostically difficult case

Nasal spindle cell rhabdomyosarcoma is very rare. The tumor is sometimes confused with other spindle cell tumors. We herein report a case of nasal spindle cell tumor in a 62-year-old woman. The patient first presented herself to a medical doctor’s office after an episode of left epistaxis. An intranasal tumor was found and resected. The tumor was composed of spindle cells, and she was diagnosed with desmoid-type fibromatosis. Five years after the initial episode, an intranasal tumor was found again. The tumor showed a fascicular growth pattern with high cellularity and was predominantly composed of spindle cells. Scattered eosinophilic rhabdomyoblasts were also observed. She was diagnosed with spindle cell rhabdomyosarcoma. This is a unique case report not only because nasal spindle cell rhabdomyosarcoma is very rare but also because the tumor was initially diagnosed as desmoid-type fibromatosis. It is important to consider spindle cell rhabdomyosarcoma as a differential diagnosis of nasal spindle cell tumors.

Early-stage multi-differentiated gastric carcinosarcoma and post-resection local recurrence: a case report

BACKGROUND

Carcinosarcoma is a rare neoplasm with a poor prognosis that is most often discovered at an advanced stage; a gastric carcinosarcoma is even rarer than carcinosarcomas originating in other organs, such as the uterus. We report our experience with an early-stage multi-differentiated gastric carcinosarcoma.

CASE PRESENTATION

A 68-year-old male patient presented with anemia, and his fecal occult blood test was positive. An endoscopic examination was conducted which revealed a hemorrhagic, irregular, protruding lesion in the stomach. The lesion was diagnosed as an adenocarcinoma by histopathological examination of the biopsy specimen, and a segmental gastrectomy was performed. A 41 × 29 × 18 mm³ protruding lesion was observed in the resection specimen, and histologically confirmed to be a gastric carcinosarcoma with mixed adenocarcinomatous and sarcomatous composition. Tumor invasion was limited to the submucosa. Besides the adenocarcinomatous portion, neuroendocrine differentiation and AFP-positive gastric carcinoma were present in the carcinomatous portion of the tumor; in the sarcomatous portion, chondrosarcomatous, leiomyosarcomatous, and rhabdomyosarcomatous components were observed in addition to the undifferentiated sarcomatous component. Furthermore, the tumor included SALL4-positive germ cell-like cells. Despite early-stage detection, the cancer recurred locally 14 months after tumor resection, which necessitated a total gastrectomy. At the 2-month follow-up after the total gastrectomy, the patient was alive. This patient had developed an esophageal squamous cell carcinoma and primary lung adenosquamous carcinoma, both of which were resected.

CONCLUSIONS

Few cases of early-stage gastric carcinosarcoma have been reported, but there are no reports of recurrence to date. Local recurrence as in this patient, and even in early-stage cases, requires cautious surveillance to check for post-resection recurrence and metastasis. The etiopathogenesis of carcinosarcoma has not yet been elucidated; however, in the present case, despite the tumor's relatively small size, it exhibited various types of differentiation in both the carcinomatous and sarcomatous components and a proliferative germ cell-like portion, which suggests that the monoclonal origin hypothesis may be a valid theory for the carcinosarcoma.

Dermal Fibroblasts Internalize Phosphatidylserine-Exposed Secretory Melanosome Clusters and Apoptotic Melanocytes

Pigmentation in the dermis is known to be caused by melanophages, defined as melanosome-laden macrophages. In this study, we show that dermal fibroblasts also have an ability to uptake melanosomes and apoptotic melanocytes. We have previously demonstrated that normal human melanocytes constantly secrete melanosome clusters from various sites of their dendrites. After adding secreted melanosome clusters collected from the culture medium of melanocytes, time-lapse imaging showed that fibroblasts actively attached to the secreted melanosome clusters and incorporated them. Annexin V staining revealed that phosphatidylserine (PtdSer), which is known as an 'eat-me' signal that triggers the internalization of apoptotic cells by macrophages, is exposed on the surface of secreted melanosome clusters. Dermal fibroblasts were able to uptake secreted melanosome clusters as did macrophages, and those fibroblasts express TIM4, a receptor for PtdSer-mediated endocytosis. Further, co-cultures of fibroblasts and melanocytes demonstrated that dermal fibroblasts internalize PtdSer-exposed apoptotic melanocytes. These results suggest that not only macrophages, but also dermal fibroblasts contribute to the collection of potentially toxic substances in the dermis, such as secreted melanosome clusters and apoptotic melanocytes, that have been occasionally observed to drop down into the dermis from the epidermis.

Serious takotsubo cardiomyopathy: an autopsy case presenting severe irreversible myocardial damage after frequent episodes of recurrence

Background

Takotsubo cardiomyopathy is characterized by transient dysfunction of the medial to apical segment of the left ventricle. Recurrence within a few months or years has been reported and serious complications, including arrhythmia, acute cardiac shock and cardiac rupture, can arise; however, recurrence is rare and takotsubo cardiomyopathy is typically a reversible functional disorder.

Case presentation

A 91-year-old Japanese woman with a past medical history of angina pectoris, hypertension and uterine carcinoma noted bilateral axillary pain and presented herself to an emergency room. Although the pain improved and she went home, there were several subsequent episodes of recurrent chest pain. At approximately 1 week after the onset, she was hospitalized as her symptom worsened. Electrocardiography showed low voltage in limb and chest leads, and ST-segment elevation in leads II, III, aVF and V3 to V6. Echocardiography revealed medial to apical dyskinesia and basal hypercontractility of the left ventricle, and cardiac tamponade. Pericardiocentesis improved the symptom, but not her cardiac dysfunction. At 3 days after her admission, cardiopulmonary resuscitation was performed due to ventricular fibrillation. She died on the 5th day of admission (2 weeks after the onset). At autopsy, the left ventricle was dilatated and the apical ventricular wall was thin. On microscopy, remarkable wavy change and thinning of myocardium were diffusely observed, especially at the apex and the anterior to lateral wall of the left ventricle, interventricular septum and right ventricle, intermingled with interstitial fibrosis, hemorrhage and neutrophil infiltration. Contraction band necrosis was mainly observed on the posterior to inferior wall of the left ventricle.

Conclusion

Our case showed severe morphological myocardial change after several chest pain episodes that were considered to be takotsubo cardiomyopathy. This notable case suggests that the frequent recurrence of serious takotsubo cardiomyopathy is life threatening and can lead to irreversible serious myocardial degeneration.

A case report of fibroadenoma of the breast with characteristic cystic change on a cut surface

Fibroadenoma with remarkable cystic change is very unusual. Opinions differ as to the interpretation of this lesion. Furthermore, there have been few reports focusing on its macroscopic view. We herein report a case of fibroadenoma in a 43-year-old woman. The patient presented herself to a medical doctor's office due to a rapidly growing breast tumor. Based on a core needle biopsy, a benign lesion was suspected, and the tumor was surgically resected. On a macroscopic study, the cut surface of the tumor revealed a remarkably cystic and well-circumscribed lesion with an intracystic polypoid component. Microscopically, a variety of findings of epithelial and stromal proliferation were observed. This is an interesting case not only because a fibroadenoma with prominent cystic change is unusual but also because the breast tumor showed a characteristically cystic appearance on its macroscopic view.

Case report of large malignant pericardial effusion in a post-surgical setting of endometrial mixed carcinoma: A description of unique cytological, histological, and immunohistochemical findings

Appearance of endometrial carcinoma in pericardial effusion is extremely rare. Its major etiological factors include lung cancer, breast cancer, lymphoma, and leukemia. We herein report a case of a large malignant pericardial effusion 7 years after surgery for endometrial carcinoma. A 66-year-old woman who underwent modified radical hysterectomy, bilateral salpingo-oophorectomy, and lymph node dissection for endometrial carcinoma 7 years ago and who had self-interrupted subsequent chemotherapy was presented with vertigo and vomiting. Chest computed tomography revealed pericardial effusion. Cytological examination diagnosed it as adenocarcinoma with psammoma bodies and mitoses. Immunohistochemistry analysis revealed that adenocarcinoma cells were positive for p53, p16, and insulin-like growth factor II mRNA-binding protein-3, but negative for estrogen receptor. Adenocarcinoma cells in pericardial effusion were morphologically and immunohistochemically similar to the serous carcinoma component of the surgical specimen. The appearance of psammoma bodies in cytological examination triggered the diagnosis.

Rhabdomyosarcoma arising from retroperitoneal teratoma in an infantile neurofibromatosis type 1 patient

We herein report the case of a 2-year-old girl with neurofibromatosis type 1 (NF1), who presented with a 12-cm mass in the right retroperitoneum and underwent tumor resection. Histologically, the tumor was composed of two distinct components: one was teratoma, showing mature morphology; and the other was embryonal rhabdomyosarcoma. An interphase fluorescence in situ hybridization (FISH) analysis of the rhabdomyosarcoma component revealed the absence of isochromosome 12p. Although it is well known that rhabdomyosarcoma occurs in infantile NF1, and that rhabdomyosarcoma can arise from teratoma as a somatic-type malignancy, to the best of our knowledge, this is the first case of an infantile NF1 patient, who developed rhabdomyosarcoma within a retroperitoneal teratoma. The absence of chromosome 12p alteration suggests a possibility that the rhabdomyosarcoma occurred due to the NF1 background, not as a somatic-type malignancy of germ cell tumor.

The potential usefulness of sputum cytology in the conclusive diagnosis of methotrexate-associated lymphoproliferative disorders: A case report

Background:

Methotrexate has been used as an anchor drug for the treatment of rheumatoid arthritis and is considered to be a cause of methotrexate-associated lymphoproliferative disorder. Spontaneous regression can occur after withdrawal of methotrexate and may be associated with Epstein–Barr virus positivity and non-diffuse large B cell lymphoma histological type. Methotrexate-associated lymphoproliferative disorders are often diagnosed pathologically by lung biopsy. To the best of our knowledge, there have been no studies on the cytological diagnosis of methotrexate-associated lymphoproliferative disorder using sputum smears.

Case:

A 70-year-old man, who was diagnosed with rheumatoid arthritis 13 years previously and who had been treated with methotrexate, presented shortness of breath and productive cough. Methotrexate-associated lymphoproliferative disorder was suspected as the sputum cytology showed many atypical lymphoid cells with hyperchromatic enlarged nuclei, foamy cytoplasm and distinct nucleoli. Chest computed tomography revealed multiple nodular shadows with interstitial pneumonia in the bilateral lower lung field. A lung biopsy specimen contained atypical lymphoid cells that were immunohistochemically positive for CD20 and MUM-1, and weakly positive for bcl-6, but negative for CD3 and CD10. There were no Epstein–Barr virus-infectious lymphoid cells by ISH-EBER. He was finally diagnosed with methotrexate-associated lymphoproliferative disorder (non-germinal center B-cell-like diffuse large B cell lymphoma histological type). Most of the nodules disappeared spontaneously following the withdrawal of methotrexate.

Discussion and conclusion:

A cytologically conclusive diagnosis of methotrexate-associated lymphoproliferative disorder may be reached using sputum smears and clinical information.

Whitish-Yellow Tumor on its Characteristic Cut Surface: A Case Report of Congenital Granular Cell Epulis

Introduction:

Congenital granular cell epulis is a rare and benign lesion in newborn. There are some papers of the entity; however, there are very few reports focusing on its macroscopic view.

Case Presentation:

A 0-day-old boy was noted to have a mass consisting of multiple nodules on maxillary gingiva, and it was excised. The mass was measured about 2 cm in its greatest diameter. Surface of cross-section was characteristically whitish-yellow and very smooth. Histopathologically, the lesion was composed of a proliferation of large polygonal cells with demarcated cell membrane, granular cytoplasm, and small uniform nuclei. Immunohistochemically, these cells were negative for S100. The diagnosis was concluded as congenital granular cell epulis.

Discussion and Conclusion:

We reported a typical case of congenital granular cell epulis. It is noteworthy that the cross-section observed in this case was very characteristically whitish-yellow and smooth.

The impact of PRDX4 and the EGFR mutation status on cellular proliferation in lung adenocarcinoma

Background: Oxidative stress plays key roles in the progression of lung adenocarcinoma. Recently, we reported that peroxiredoxin 4 (PRDX4), an antioxidant enzyme, can be a prognostic marker of lung adenocarcinoma (LUAD). In the present study, we aimed to further investigate the relationship among the PRDX4 expression, epidermal growth factor receptor (EGFR) mutations and cell proliferation in LUAD. Methods: The expression of PRDX4 was immunohistochemically analyzed and the EGFR mutation status was examined in 127 paraffin-embedded human surgical specimens from patients with stage I LUAD. The PRDX4 expression was considered to be high when >40% of the adenocarcinoma cells were positively stained. In vitro, using plasmid transfection methods, PRDX4 plasmid DNAs were transfected into human lung adenocarcinoma cell lines, A549 (EGFR-wild) or PC-9 (EGFR mutant). The viability of these cells was analyzed using a Cell Counting Kit-8 kit. Results: The number of cases with high PRDX4 expression levels among patients with LUAD with EGFR mutations was significantly larger than that in patients with EGFR wild-type. The combination of the PRDX4 expression level with the EGFR mutation status was closely associated with the prognosis of patients with stage I LUAD. Viability assays showed that the proliferation of A549 cells was significantly suppressed after PRDX4 plasmid transfection, while the overexpression of PRDX4 had no effect on the proliferation of EGFR-mutant PC-9 cells. Conclusions: The PRDX4 expression and EGFR mutation status were significantly associated with the prognosis of patients with stage I LUAD, and EGFR mutations affected the role of PRDX4 in the proliferation of LUAD cells.

An autopsy case of peripheral T cell lymphoma occurring in a postpartum woman: a unique case suggesting changes in the immunocharacteristics of lymphoma cells before and after delivery

Background

The occurrence of malignant lymphoma after delivery is an extremely rare event. Although several cases of Hodgkin lymphoma and B cell lymphoma and a few cases of peripheral T cell lymphoma (PTCL) after delivery have been reported, there are no report of autopsy cases of PTCL in the puerperal period.

Case presentation

A 32-year-old Japanese woman with a past medical history of atopic dermatitis and bronchial asthma presented with generalized eruptions four days after the delivery of her first child; generalized skin induration and lymphadenopathy subsequently emerged. A skin biopsy specimen showed the diffuse proliferation of atypical lymphoid cells that were immunohistochemically-positive for CD4 but negative for CD8. She was diagnosed as PTCL, not otherwise specified (PTCL, NOS). She died one year and three months after the onset of symptoms. At autopsy, the systemic infiltration of lymphoma cells into the whole body was observed. Unexpectedly, these lymphoma cells were immuno-reactive with CD8 but not with CD4.

Conclusion

The occurrence and development of PTCL after delivery with the shift from CD4 positivity to CD8 positivity may be associated with not only the selection of resistant subclone as a result of chemotherapy but also the changes of immune status before and after delivery.

Deletion of Prdm8 impairs development of upper-layer neocortical neurons

Upper-layer (UL) neocortical neurons are the most prominent distinguishing features of the mammalian neocortex compared with those of the avian dorsal cortex and are vastly expanded in primates. However, little is known about the identities of the genes that control the specification of UL neurons. Here, we found that Prdm8, a member of the PR (PRDI-BF1 and RIZ homology) domain protein family, was specifically expressed in the postnatal UL neocortex, particular those in late-born RORß-positive layer IV neurons. We generated homozygous Prdm8 knockout (Prdm8 KO) mice and found that the deletion of Prdm8 causes growth retardation and a reduced brain weight, although the brain weight-to-body weight ratio is unchanged at postnatal day 8 (P8). Immunohistochemistry showed that the relative UL thickness, but not the thickness of the deep layer (DL), was significantly reduced in Prdm8 KO mice compared with wild-type (WT) mice. In addition, we found that a number of late-born Brn2-positive UL neurons were significantly decreased in Prdm8 KO mice. To identify genes regulated by Prdm8 during neocortical development, we compared expression profiling analysis in Prdm8 KO and WT mice, and identified some candidate genes. These results suggest that the proper expression of Prdm8 is required for the normal development and construction of UL neurons in the mammalian neocortex.

NF-κB signaling regulates the generation of intermediate progenitors in the developing neocortex

In addition to its well-established role during immune system function, NF-κB regulates cell survival and synaptic plasticity in the mature nervous system. Here, we show that during mouse brain development, NF-κB activity is present in the neocortical ventricular and subventricular zones (VZ and SVZ), where it regulates proliferative pool maintenance. Activation of NF-κB signaling, by expression of p65 or an activated form of the IκB kinase complex subunit IKK2, inhibited neuronal differentiation and promoted retention of progenitors in the VZ and SVZ. In contrast, blockade of the pathway with dominant negative forms of IKK2 and IκBα promoted neuronal differentiation both in vivo and in vitro. Furthermore, by modulating both the NF-κB and Notch pathways, we show that in the absence of canonical Notch activity, after knockdown of the pathway effector CBF1, NF-κB signaling promoted Tbr2 expression and intermediate neural progenitor fate. Interestingly, however, activation of NF-κB in vivo, with canonical Notch signaling intact, promoted expression of the radial glial marker Pax6. This work identifies NF-κB signaling as a regulator of neocortical neurogenesis and suggests that the pathway plays roles in both the VZ and SVZ.

Prdm8 regulates the morphological transition at multipolar phase during neocortical development

Here, we found that the PR domain protein Prdm8 serves as a key regulator of the length of the multipolar phase by controlling the timing of morphological transition. We used a mouse line with expression of Prdm8-mVenus reporter and found that Prdm8 is predominantly expressed in the middle and upper intermediate zone during both the late and terminal multipolar phases. Prdm8 expression was almost coincident with Unc5D expression, a marker for the late multipolar phase, although the expression of Unc5D was found to be gradually down-regulated to the point at which mVenus expression was gradually up-regulated. This expression pattern suggests the possible involvement of Prdm8 in the control of the late and terminal multipolar phases, which controls the timing for morphological transition. To test this hypothesis, we performed gain- and loss-of-function analysis of neocortical development by using in utero electroporation. We found that the knockdown of Prdm8 results in premature change from multipolar to bipolar morphology, whereas the overexpression of Prdm8 maintained the multipolar morphology. Additionally, the postnatal analysis showed that the Prdm8 knockdown stimulated the number of early born neurons, and differentiated neurons located more deeply in the neocortex, however, majority of those cells could not acquire molecular features consistent with laminar location. Furthermore, we found the candidate genes that were predominantly utilized in both the late and terminal multipolar phases, and these candidate genes included those encoding for guidance molecules. In addition, we also found that the expression level of these guidance molecules was inhibited by the introduction of the Prdm8 expression vector. These results indicate that the Prdm8-mediated regulation of morphological changes that normally occur during the late and terminal multipolar phases plays an important role in neocortical development.

Differential Notch signalling distinguishes neural stem cells from intermediate progenitors

During brain development, neurons and glia are generated from a germinal zone containing both neural stem cells (NSCs) and more limited intermediate neural progenitors (INPs). The signalling events that distinguish between these two proliferative neural cell types remain poorly understood. The Notch signalling pathway is known to maintain NSC character and to inhibit neurogenesis, although little is known about the role of Notch signalling in INPs. Here we show that both NSCs and INPs respond to Notch receptor activation, but that NSCs signal through the canonical Notch effector C-promoter binding factor 1 (CBF1), whereas INPs have attenuated CBF1 signalling. Furthermore, whereas knockdown of CBF1 promotes the conversion of NSCs to INPs, activation of CBF1 is insufficient to convert INPs back to NSCs. Using both transgenic and transient in vivo reporter assays we show that NSCs and INPs coexist in the telencephalic ventricular zone and that they can be prospectively separated on the basis of CBF1 activity. Furthermore, using in vivo transplantation we show that whereas NSCs generate neurons, astrocytes and oligodendrocytes at similar frequencies, INPs are predominantly neurogenic. Together with previous work on haematopoietic stem cells, this study suggests that the use or blockade of the CBF1 cascade downstream of Notch is a general feature distinguishing stem cells from more limited progenitors in a variety of tissues.

Progenitors resume generating neurons after temporary inhibition of neurogenesis by Notch activation in the mammalian cerebral cortex

The mammalian cerebral cortex comprises six layers of neurons. Cortical progenitors in the ventricular zone generate neurons specific to each layer through successive cell divisions. Neurons of layer VI are generated at an early stage, whereas later-born neurons occupy progressively upper layers. The underlying molecular mechanisms of neurogenesis, however, are relatively unknown. In this study, we devised a system where the Notch pathway was activated spatiotemporally in the cortex by in vivo electroporation and Cre-mediated DNA recombination. Electroporation at E13.5 transferred DNA to early progenitors that gave rise to neurons of both low and upper layers. Forced expression of a constitutively active form of Notch (caNotch) at E13.5 inhibited progenitors from generating neurons and kept progenitors as proliferating radial glial cells. After subsequent transfection at E15.5 of a Cre expression vector to remove caNotch, double-transfected cells, in which caNotch was excised, migrated into the cortical plate and differentiated into neurons specific to upper layers. Bromodeoxyuridine-labeling experiments showed that the neurons were born after Cre transfection. These results indicate that cortical progenitors that had been temporarily subjected to Notch activation at an early stage generated neurons at later stages, but that the generation of low-layer neurons was skipped. Moreover, the double-transfected cells gave rise to upper-layer neurons, even after their transplantation into the E13.5 brain, indicating that the developmental state of progenitors is not halted by caNotch activity.

The Sox-2 regulatory regions display their activities in two distinct types of multipotent stem cells

The Sox-2 gene is expressed in embryonic stem (ES) cells and neural stem cells. Two transcription enhancer regions, Sox-2 regulatory region 1 (SRR1) and SRR2, were described previously based on their activities in ES cells. Here, we demonstrate that these regulatory regions also exert their activities in neural stem cells. Moreover, our data reveal that, as in ES cells, both SRR1 and SRR2 show their activities rather specifically in multipotent neural stem or progenitor cells but cease to function in differentiated cells, such as postmitotic neurons. Systematic deletion and mutation analyses showed that the same or at least overlapping DNA elements of SRR2 are involved in its activity in both ES and neural stem or progenitor cells. Thus, SRR2 is the first example of an enhancer in which a single regulatory core sequence is involved in multipotent-state-specific expression in two different stem cells, i.e., ES and neural stem cells.

Analyses of differential gene expression in genetic hypertensive rats by microarray

We identified genes that were differentially expressed between spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY) using cDNA microarray analysis, and analyzed the correlation between these genes and hypertension. Twenty four genes were found to be up-regulated and 20 were down-regulated in SHR. We selected 11 genes (6 up-regulated genes: SAH, Hsp70, MCT1, RBP, IDI1, Prion; and 5 down-regulated genes: Thrombin, Dyn, SOD3, Ela1, Gst Y(b)) and subjected them to an F2 cosegregation analysis. One hundred five F2 rats were obtained from the same strains used for microarray analysis, and blood pressure was measured directly with a catheter implanted in the femoral artery. The genotypes of monocarboxylate transporter 1 and glutathione S-transferase Y(b) subunit significantly affected diastolic blood pressure in F2 rats, and these two genes are located near each other on chromosome 2. However, quantitative trait loci (QTL) analysis in this region revealed that the QTL for diastolic blood pressure were from these two genes. Antihypertensive treatment with either enalapril or hydralazine only affected the expression level of Hsp70, which was up-regulated by hydralazine, probably through compensatory sympathetic activation. We were unable to associate the other 10 genes with hypertension in SHR. Based on these results, the identification of differentially expressed genes may not be an efficient method for selecting candidate genes for hypertension in the SHR-WKY system.

Kynureninase is a novel candidate gene for hypertension in spontaneously hypertensive rats

The rostral ventrolateral medulla (RVLM) plays a critical role in the tonic and reflexive regulation of arterial blood pressure. Recent studies have demonstrated that injection of kynurenic acid (KYN) into the RVLM of spontaneously hypertensive rats (SHR) decreases arterial blood pressure. We hypothesized that a relative increase in the excitatory amino acid-mediated drive of RVLM vasomotor neurons in SHR may be due to derangement of one of the enzymes that affect the KYN level in the brain. We selected kynureninase, kynureninase hydroxylase, kynurenine aminotransferase type I, and kynurenine aminotransferase type II as candidates that may affect the KYN level in the brainstem. We conducted association studies between polymorphisms of these genes and blood pressure in an F2 population derived from SHR and Wistar-Kyoto rats (WKY). The cosegregation analysis indicated that only the kynureninase gene (KYNU) polymorphism influenced systolic blood pressure (SBP) and residuals of systolic blood pressure after adjusting for heart rate and body weight (RSBP). KYNU was found to be located on rat chromosome 3, and quantitative trait loci analysis at this locus indicated that the logarithms of the odds scores for KYNU in terms of SBP and RSBP were 2.0 and 3.3, respectively. This association with blood pressure decreased in proportion to the distance from KYNU. The expression level of KYNU mRNA in the brainstem was about 3.1 and 2.9 times higher in 10-week-old and 16-week-old SHR than in age-matched WKY, respectively. The increased expression of KYNU in SHR is thought to decrease the KYN level. KYNU seems to be one of the genes that contributes to hypertension in SHR.