Pharmacokinetics of L-theanine and the effect on amino acid composition in mice administered with L-theanine.

L-theanine, an amino acid component of the tea leaves of Camellia sinensis, is sold in Japan as a supplement for good sleep. Although several studies in humans and mice have reported the effects of L-theanine on brain function, only a few reports have comprehensively clarified the disposition of theanine administered to mice and its effects on concentrations of other blood amino acids. In this study, we aimed to determine the changes in the blood levels of L-theanine administered to mice and amino acid composition of the serum. L-theanine were administered to four-week-old Std-ddY male mice orally or via tail vein injection. L-theanine and other amino acids in serum prepared from blood collected at different time points post-dose were labeled with phenylisothiocyanate and quantified. The serum concentration of orally administered L-theanine peaked 15 min after administration. The area under the curve for tail vein injection revealed the bioavailability of L- theanine to be approximately 70%. L-theanine administration did not affect any amino acid levels in the serum, but a significant increase in the peak area overlapping the Glycine (Gly) peak was observed 30 min after administration. L-theanine administered to mice was rapidly absorbed and eliminated, suggesting that taking L-theanine as a supplement is safe without affecting its own levels or serum levels of other amino acids. However, considering that Gly, similar to L-theanine, is used as a dietary supplement for its anxiolytic effects and to improve sleep, determining the effects of L-theanine administration on Gly is important and needs further research.

Pharmacist perceptions of a "good death" and differences in perception between patients with cancer, oncologists, and oncology nurses: a questionnaire survey.

BACKGROUND: For pharmacists expected to encounter the deaths of many of their patients in the near future, it is important to understand the perception of a "good death" for patients with cancer who are likely to be aware of the circumstances of their poor prognosis. In this study, we clarified pharmacists' perceptions of a "good death" and considered the differences in perception among patients with cancer, oncologists, and oncology nurses. METHODS: From April to June 2022, an anonymous questionnaire survey was conducted on pharmacists working in hospitals and pharmacies and on members of the Japanese Society for Pharmaceutical Palliative Care and Sciences. The questionnaire consisted of 57 questions, called attributes, developed by Miyashita et al. to investigate the perception of "good death" in Japanese cancer medicine. The importance of those attributes was investigated using a 7-point Likert scale. RESULTS: Three thousand four hundred thirty-two pharmacists were made aware of this survey, and 207 participated in the survey. The responses of pharmacists to the 57 questions were very similar to those of the oncologists. Among them, "Fighting against disease until one's last moment" and "Not making trouble for others" had very low importance, which was the most significantly different from the responses of patients with cancer. "Fighting against disease until one's last moment" tended to be significantly underestimated by pharmacists engaged in patient guidance and interview compared to that by pharmacists not engaged in the duty (p = 0.02). Also, when we compared pharmacists with or without qualifications related to cancer and palliative care, there was no significant difference in the importance of "Fighting against disease until one's last moment." However, the importance of "Not making trouble for others" for qualified pharmacists was significantly underestimated (p = 0.04). CONCLUSION: Since pharmacists understand the limits of chemotherapy, they may want to be close to the patient but may not strongly agree with the "Fighting against cancer" component that patients with cancer prefer. It may be necessary to reconsider better ways of approaching the wishes and satisfaction of patients with cancer under the care of medical professionals in the field of oncology.

Role of afadin in vascular endothelial growth factor- and sphingosine 1-phosphate-induced angiogenesis.

RATIONALE: Angiogenesis contributes to physiological and pathological conditions, including atherosclerosis. The Rap1 small G protein regulates vascular integrity and angiogenesis. However, little is known about the effectors of Rap1 involved in angiogenesis. It is not known whether afadin, an adherens junction protein that connects immunoglobulin-like adhesion molecule nectins to the actin cytoskeleton and binds activated Rap1, plays a role in angiogenesis. OBJECTIVE: We investigated the role of endothelial afadin in angiogenesis and attempted to clarify the underlying molecular mechanism. METHODS AND RESULTS: Treatment of human umbilical vein endothelial cells (HUVECs) with vascular endothelial growth factor (VEGF) and sphingosine 1-phosphate (S1P) induced the activation of Rap1. Activated Rap1 regulated intracellular localization of afadin. Knockdown of Rap1 or afadin by small interfering RNA inhibited the VEGF- and S1P-induced capillary-like network formation, migration, and proliferation, and increased the serum deprivation-induced apoptosis of HUVECs. Knockdown of Rap1 or afadin decreased the accumulation of adherens and tight junction proteins to the cell-cell contact sites. Rap1 regulated the interaction between afadin and phosphatidylinositol 3-kinase (PI3K), recruitment of the afadin-PI3K complex to the leading edge, and the activation of Akt, indicating the involvement of Rap1 and afadin in the PI3K-Akt signaling pathway. Binding of afadin to Rap1 regulated the activity of Rap1 in a positive-feedback manner. In vivo, conditional deletion of afadin in mouse vascular endothelium using a Cre-loxP system impaired the VEGF- and S1P-induced angiogenesis. CONCLUSIONS: These results demonstrate a novel molecular mechanism by which Rap1 and afadin regulate the VEGF- and S1P-induced angiogenesis.

Localization of nectin-free afadin at the leading edge and its involvement in directional cell movement induced by platelet-derived growth factor.

Afadin is an actin-filament-binding protein that binds to nectin, an immunoglobulin-like cell-cell adhesion molecule, and plays an important role in the formation of adherens junctions. Here, we show that afadin, which did not bind to nectin and was localized at the leading edge of moving cells, has another role: enhancement of the directional, but not random, cell movement. When NIH3T3 cells were stimulated with platelet-derived growth factor (PDGF), afadin colocalized with PDGF receptor, alphavbeta3 integrin and nectin-like molecule-5 at the leading edge and facilitated the formation of leading-edge structures and directional cell movement in the direction of PDGF stimulation. However, these phenotypes were markedly perturbed by knockdown of afadin, and were dependent on the binding of afadin to active Rap1. Binding of Rap1 to afadin was necessary for the recruitment of afadin and the tyrosine phosphatase SHP-2 to the leading edge. SHP-2 was previously reported to tightly regulate the activation of PDGF receptor and its downstream signaling pathway for the formation of the leading edge. These results indicate that afadin has a novel role in PDGF-induced directional cell movement, presumably in cooperation with active Rap1 and SHP-2.

Is the Meaning of the "Sharing Economy" Shared Among Us? Comparing the Perspectives of Japanese and Swedish Researchers.

In this paper, we aim to investigate how researchers in Japan and Sweden perceive and approach the term "sharing economy" in research publications. Systematic literature reviews were used to explore academic discussions in both countries. The main finding of this research is that although researchers in both contexts use similar definitions and concepts, the meanings and connotations of the sharing economy differ among the two contexts. In summary, Japanese researchers tend to focus first and foremost on the economic effects of the sharing economy, as it serves the purpose of economic revitalisation. In contrast, Swedish researchers focus on its environmental effects. The differences reflect country-specific socio-cultural, technological, and economic contexts. Finally, we suggest future directions for research and policy development.

[Construction of Pre-clinical Practice and Survey of Consciousness for Pharmacy Students with Hearing Disability].

Various types of pre-learning-including pre-learning for practical training-provide pharmacy students with practical training and sufficient knowledge, skills, and attitudes for practical work. Opportunities in the medical field, including for pharmacists, have been greatly expanded for students with a hearing disability, and we have responded with appropriate training for such students. In this study, we report on the results of an evaluation of a survey on the preparatory training conducted by the students and the changes in their consciousness, such as in their level of understanding, knowledge, and self-confidence. Before the training, the participants' anxiety concerning items related to dispensing and communication were quite high; after the training, however, these anxiety levels were reduced. In addition, we were able to encourage the participant's concern for people and to face the difficulty of expressing words in letters, as well as to drive enthusiasm for the Objective Structured Clinical Examination (OSCE) and practical training. These results suggest that having a teacher as an assistant is useful for helping students with hearing disability in practical training.

[Survey of Nurse and Community Pharmacist Collaboration and Expectations of Nurses in Community Care Systems].

The purpose of this study was to clarify the current status of collaboration between nurses and community pharmacists as well as the requests and expectations that community pharmacists have of nurses in community-based comprehensive care systems. Questionnaires requiring open-ended responses were sent to 867 pharmacies throughout Fukushima prefecture (excluding four suspended pharmacies). We asked one pharmacist at each facility to answer the questions. We then analyzed the collected questionnaires using descriptive statistics, including the current status of nurse cooperation and the basic information about the pharmacies. Additionally, the open-ended descriptions of nurses' requests and expectations were analyzed quantitatively and qualitatively. The questionnaire collection rate was 32% (278 cases), and the breakdown of pharmacies that responded was 68.0% for facilities with 1 or 2 full-time pharmacists and 27.0% for facilities with 3 to 5 pharmacists. About 30% of respondents reported contact with the nursing profession at least once a week, while about 50% reported no contact at all or several times a year. The types of nurses collaborating with the pharmacies were clinic nurses (54.6%) and visiting nurses (43.4%). Some pharmacists had expected nurses to work cooperatively and rely on pharmacists. These results indicate that only about half of the pharmacists had opportunities to cooperate with nurses. For trust to be established between nurses and pharmacists, it is necessary for nurses to ask the pharmacists about medication and consult with them about patient medication management.

Involvement of afadin in the formation and remodeling of synapses in the hippocampus.

In the hippocampus, synapses are formed between mossy fiber terminals and CA3 pyramidal cell dendrites and comprise highly developed synaptic junctions (SJs) and puncta adherentia junctions (PAJs). Dynamic remodeling of synapses in the hippocampus is implicated in learning and memory. Components of both the nectin-afadin and cadherin-catenin cell adhesion systems exclusively accumulate at PAJs. We investigated the role of afadin at synapses in mice in which the afadin gene was conditionally inactivated in hippocampal neurons. In these mutant mice, the signals for not only nectins, but also N-cadherin and beta-catenin, were hardly detected in the CA3 area, in addition to loss of the signal for afadin, resulting in disruption of PAJs. Ultrastructural analysis revealed an increase in the number of perforated synapses, suggesting the instability of SJs. These results indicate that afadin is involved not only in the assembly of nectins and cadherins at synapses, but also in synaptic remodeling.

Helicobacter pylori augments growth of gastric cancers via the lipopolysaccharide-toll-like receptor 4 pathway whereas its lipopolysaccharide attenuates antitumor activities of human mononuclear cells.

PURPOSE: Helicobacter pylori is reportedly involved in the development of gastric cancer. We investigated the mechanisms by which H. pylori affects gastric cancer growth and antitumor immunities in the host, focusing on H. pylori-derived lipopolysaccharide (LPS). EXPERIMENTAL DESIGN: H. pylori and four gastric cancer cell lines (MKN28, MKN45, NUGC3, and KATOIII) were used. We examined the effect of H. pylori or its LPS stimulation on cancer growth and the involvement of the H. pylori LPS-toll-like receptor 4 (TLR4) pathway. We also examined the cytotoxicities of H. pylori/LPS-stimulated human mononuclear cells (MNC) against gastric cancer cells and the effect of H. pylori LPS stimulation on cytokine production by MNC. RESULTS: H. pylori, as well as its LPS, augmented the growth of gastric cancers, all of which expressed TLR4. Neutralization of TLR4 almost completely abrogated the H. pylori-induced proliferative activity of cancer cells. Escherichia coli LPS also augmented cancer growth via the LPS-TLR4 pathway. However, only H. pylori-derived LPS attenuated the cytotoxicity of MNC against gastric cancer cells. Stimulation with H. pylori/LPS also down-regulated perforin production in cancer cell-cocultured CD56+ natural killer cells. H. pylori LPS induced neither interleukin-12 nor IFN-gamma production by MNC, although E. coli LPS did induce production of both significantly. Nevertheless, interleukin-12 stimulation restored the IFN-gamma-producing capacity of H. pylori LPS-stimulated MNC. CONCLUSION: H. pylori augmented the growth of gastric cancers via the LPS-TLR4 pathway, whereas it attenuated the antitumor activity and IFN-gamma-mediated cellular immunity of MNC. H. pylori infection might thereby promote proliferation and progression of gastric cancers.

Gastric cancer cells exploit CD4+ cell-derived CCL5 for their growth and prevention of CD8+ cell-involved tumor elimination.

The level of serum CCL5, a C-C chemokine, is reportedly correlated with tumor progression in several cancers. We herein investigated the mechanisms by which CCL5 might contribute to tumor progression in gastric cancer. Serum CCL5 levels significantly correlated with tumor progression and prognosis in patients with gastric cancer. Immunohistochemistry showed that tumor-infiltrating lymphocytes expressed CCL5, while the tumor cells expressed the CCL5 receptors. Fluorescent double staining showed that tumor-infiltrating CD4+ cells rather than CD8+ cells preferentially expressed CCL5. Using gastric cancer cell lines (MKN45, KATO III), we examined CCL5 production by coculturing whole peripheral blood mononuclear cells (PBMCs), CD4+ cells, or CD8+ cells, with tumor cells. CD4+ cells cocultured with tumor cells remarkably enhanced CCL5 production in a direct cell-cell contact manner over other cocultured PBMCs, including CD8+ cells. Gastric cancer cell lines expressed CCL5 receptors and augmented their proliferation in response to CCL5 stimulation. Furthermore, we examined the effect of CCL5-treated cancer cells on the cocultured PBMCs, focusing on the CD4+/CD8+ proportion and apoptosis. Coculture of CCL5-treated gastric cancer cells with PBMCs resulted in a significant decrease in the proportion of CD8+ cells but not CD4+ cells, suggesting Fas-FasL-mediated apoptosis in CD8+ cells. In immunodeficient mice coinjected with KATO III and PBMCs, neutralization of CCL5 significantly suppressed tumor progression, resulting in a favorable outcome. In conclusion, gastric cancer cells might thus induce CD4+ T cells to secrete CCL5 and exploit it for their progression, as well as to aid in the prevention of CD8+ T cell-involved tumor elimination.

A tissue-engineered stomach shows presence of proton pump and G-cells in a rat model, resulting in improved anemia following total gastrectomy.

Despite advances in surgical reconstruction, total gastrectomy still is accompanied by various complications, especially chronic ones, such as pernicious anemia, resulting in refractory malnutrition. As an alternative approach, we have proposed a tissue-engineered stomach as a replacement of the native stomach. This study aimed to assess the secretory functions of a tissue-engineered stomach in a rat model and the nutritional status of the recipients over an extended time period. Stomach epithelial organoid units were isolated from neonatal rats and seeded onto biodegradable polymers. These constructs were implanted into the omenta of adult recipient rats. After 3 weeks, cyst-like structures had formed, henceforth referred to as tissue-engineered stomachs. The recipient stomachs were resected and replaced by their tissue-engineered counterparts. At 24 weeks after implantation, the secretory function of the tissue-engineered stomach was evaluated using immunohistochemical staining. The hemoglobin levels and nutritional status of the recipients were compared with a control group that had undergone a simple Roux-en-Y reconstruction following total gastrectomy. Recipient rats tolerated the tissue-engineered stomachs well. X-ray examination using barium as contrast showed no bowel stenosis. Staining for proton pump alpha-subunit and gastrin demonstrated the existence of parietal cells and G-cells in the neogastric mucosa, respectively, suggesting secretory functions. The treatment group showed significantly higher hemoglobin levels than the control group, although no differences in the body weight change, total protein, or cholesterol levels were observed between the two groups. A tissue-engineered stomach has the potential to function as a food reservoir following total gastrectomy. It is conjectured that replacement with a tissue-engineered stomach might restore the proton pump parietal cells and G-cells, and thereby improve anemia after a total gastrectomy in a rat model.

[Outcomes of Pharmaceutical Faculty-focused Introduction to Nursing Education for Pharmacy Students: A Questionnaire Survey].

　The scope of pharmaceutical education in Japan has been expanding, and with it an awareness of the importance of team medical care. However, pharmaceutical education still gives little attention to the psychosocial aspects of care, instead focusing on the structures and functions of drugs. In contrast, nursing education emphasizes the fact that medical care involves patients' family and significant others as much as the patients themselves, and thus nursing students are taught the basic needs and developmental stages of those people requiring care alongside their practical nursing skills. In this study, we examined the effect of incorporating certain aspects of introductory nursing education into pharmaceutical education on the self-efficacy of pharmaceutical students. We thus ran an introduction to nursing education course for fourth-year pharmaceutical students (n=86). After the course had finished, we surveyed students about the course. Approximately 94.2% of the students became more interested in team medical care and nearly all (98.8%) thought that what they had learned in the course would be useful in their career. The results indicated that the introduction to nursing education course offered students an opportunity to acquire different viewpoints on clinical situations because the lectures were given by a pharmacist with a nurse license and they were based on his clinical experiences. We therefore propose that more facets of introductory nursing education be incorporated into pharmaceutical education to help students develop their ability to consider patients' psychosocial backgrounds.

AORTIC INJURY DUE TO PARAGLIDING: A CASE REPORT.

A 64-year-old male fell from an altitude of 10 m while paragliding after stalling due to the wind. The purpose of this case report is to describe the outcomes after multiple injuries sustained during a paragliding accident, including a potentially life-threating injury to the thoracic aorta. The subject sustained a bite wound on his tongue, injuries to his chest (left side) and back, and a right forearm deformity. Enhanced whole body computed tomography (CT) revealed fractures of the bilateral laminae of the second and third cervical bones, right first rib, the tenth thoracic vertebral body (compression type), second lumbar vertebral body (burst type) and the right radius, Other injuries included an injury to the thoracic aortic arch and the presence of intraabdominal fluid collection without perforation of the digestive tract. Endovascular treatment was selected for the aortic injury because of multiple injuries. Immediate management included hypotensive rate control therapy using calcium and a beta blocker. On the fourth hospital day, the subject underwent deployment of a stent-graft to the aorta and subsequent surgical immobilization for the lumbar burst fracture. He also underwent surgical immobilization of the radial fracture and was discharged on the 28th hospital day. First responders or physicians should consider the possibility of aortic injury when treating patients who suffer falls while paragliding and provide appropriate management. Failure to provide appropriate management of an aortic injury could result in death. LEVEL OF EVIDENCE: 4.

Neutrophil elastase, MIP-2, and TLR-4 expression during human and experimental sepsis.

Highly activated neutrophils play a critical role in mediating organ injury in sepsis by releasing neutrophil elastase (NE). Toll-like receptors (TLRs) play an important role in the host defense against invading microbes, and their signaling pathway is critical to the activation of the proinflammatory response. However, the relationship between TLR expression and the host defense mechanism during sepsis has not been fully elucidated. In this paper, we investigated the relationships among chemokine (MIP-2), TLR-4, and NE expression in human sepsis and murine peritonitis (CLP). TLR-4 expression on monocytes/macrophages was examined in patients with sepsis and in murine peritonitis and was markedly increased in both populations. LPS-induced MIP-2 production by bronchoalveolar cells and liver mononuclear cells in mice with peritonitis was also significantly increased compared with sham-operated mice. Pretreatment of the macrophage cell line, RAW 264.7 cells, with a NE inhibitor before their exposure to LPS resulted in a significant dose-dependent decrease in MIP-2 production, which was comparable to that seen following pretreatment with TLR-4 antibody. Furthermore, NE and LPS both up-regulated TLR-4 expression on human peripheral blood monocytes. Thus, chemokine-induced recruitment of neutrophils in sepsis may result in further increased chemokine production and increased expression of TLR-4. Neutrophil-derived NE may be associated with increased expression of monocyte/macrophage TLR-4, thereby serving as a positive feedback loop for the inflammatory response among the different cell populations.

Hemoperfusion with polymyxin B-immobilized fibers reduced the number of CD16+ CD14+ monocytes in patients with septic shock.

BACKGROUND: CD16+ CD14+ monocytes dramatically increase in number in patients with severe infection. Hemoperfusion with PMX-F (direct hemoperfusion with polymyxin B immobilized fibers) has been reported to be a safe and effective treatment for patients with septic shock, although the molecular mechanism that accounts for its effectiveness is still unclear. The purpose of this study was to quantify the number of CD16+ CD14+ monocytes in patients with an intra-abdominal infection and to evaluate the effects of PMX-F treatment on clinical parameters and leukocyte surface antigen expression in these patients. MATERIALS AND METHODS: Seventeen septic patients who had an intra-abdominal infection were enrolled in this study; 7 of these patients received PMX-F treatment. Peripheral blood samples were obtained immediately after admission, and were also collected from the above 7 patients before, during, and immediately after their PMX-F treatment. The expression of CD14, CD16, and Toll-like receptor (TLR)-4 on these patients' monocytes was evaluated using flow cytometry. In addition, lipopolysaccharide (LPS)-induced production of TNF-alpha and IL-1beta by these cells was measured by ELISA. RESULTS: Monocytic expression of CD16 and TLR-4 was significantly greater in septic patients than in healthy controls, and their proportion of CD16+ CD14+ monocytes was similarly elevated. LPS-induced production of TNF-alpha and IL-1beta by peripheral blood mononuclear cells (PBMCs) of septic patients was significantly reduced compared to controls. Furthermore, there was a reduction in the proportion of CD16+ CD14+ monocytes during PMX-F treatment, and in the expression of TLR-4 on monocytes after PMX-F treatment. CONCLUSIONS: These results showed that the number of peripheral blood CD16+ CD14+ monocytes and monocytic TLR-4 expression were markedly increased, and the production of pro-inflammatory cytokines in response to LPS significantly reduced in patients with sepsis. PMX-F treatment was found to be effective in reducing the number of CD16+ CD14+ monocytes and in decreasing the monocytic expression of TLR-4 in patients with septic shock.

The increase of CD57+ T cells in the peripheral blood and their impaired immune functions in patients with advanced gastric cancer.

In addition to natural killer (NK) cells, T cells expressing natural killer cell markers, CD56 or CD57 (NK type T cells), have been considered to play an important role in antitumor immunity. We examined the proportion of NK cell and NK type T cell subsets in the peripheral blood from patients with gastric cancer. The IFN-gamma production capacity and population of cytoplasmic perforin positive cells in peripheral blood mononuclear cells (PBMC) were evaluated. Peripheral blood samples were obtained from 56 patients with gastric cancer and 21 healthy volunteers. The proportion of CD56- CD57+ T cells (CD57+ T cells) was significantly higher in advanced gastric cancer patients than those in healthy volunteers and patients with early stage gastric cancer, whereas no correlation was observed between the proportion of CD56+ T cells or NK cells and tumor progression. Furthermore, a significant decrease of CD8+ CD57+ T cells was found in patients with advanced gastric cancer. The proportion of CD57+ T cells did not correlate with interferon-gamma (IFN-gamma) production from PBMC in gastric cancer patients, although a significant correlation was found between them in healthy volunteers. The proportion of perforin positive CD57+ T cells, especially CD8+ CD57+ T cells, in patients with gastric cancer was markedly lower than that in healthy volunteers. Collectively, although the proportion of CD57+ T cells in PBMC was found to increase with tumor progression, their function in antitumor immunity is impaired in patients with gastric cancer.

The influence of interleukin-10 and interleukin-18 on interferon-gamma production by peritoneal exudate cells in patients with gastric carcinoma.

Although the peritoneal cavity (PC) is the most common site of metastasis in gastric carcinoma, its immune status in patients with advanced cancer remains largely unknown. We investigated the relationship between clinical parameters and cytokine levels in the PC and also evaluated IFN-y production by peritoneal exudate cells (PEC), obtained during surgery from patients with stage III-IV gastric carcinoma. Although the IFN-gamma and IL-12 levels in the PC did not differ between stage III and stage IV cancer patients, the latter had higher levels of IL-10 and IL-18. Those patients with higher IFN-gamma levels experienced a significantly better survival-rate than those with lower IFN-gamma levels, whereas IL-18 (but not IL-10) levels were inversely-correlated with survivaL IFN-gamma levels increased in parallel with IL-18 levels in patients who survived more than two years, but this correlation did not apply to patients who died of disease within two years. In addition, anti-CD3-Ab or cytokine- stimulated PEC from patients with low IL-10 levels in their PC produced a significantly greater amount of IFN-gamma than PEC from patients with high PC IL-10 levels. In conclusion, a high level of IFN-y in the PC is an indicator of favorable outcome. Both IL-10 and IL-18 levels in the PC increased with tumor progression. Although the number of PEC capable of producing IFN-gamma increases with tumor progression, their ability to secrete IFN-gamma in response to IL-18 may be influenced by local IL-10 levels in the PC.

An Adaptor Molecule Afadin Regulates Lymphangiogenesis by Modulating RhoA Activity in the Developing Mouse Embryo.

Afadin is an intracellular binding partner of nectins, cell-cell adhesion molecules, and plays important roles in the formation of cell-cell junctions. Afadin-knockout mice show early embryonic lethality, therefore little is known about the function of afadin during organ development. In this study, we generated mice lacking afadin expression in endothelial cells, and found that the majority of these mice were embryonically lethal as a result of severe subcutaneous edema. Defects in the lymphatic vessels of the skin were observed, although the morphology in the blood vessels was almost normal. Severe disruption of VE-cadherin-mediated cell-cell junctions occurred only in lymphatic endothelial cells, but not in blood endothelial cells. Knockout of afadin did not affect the differentiation and proliferation of lymphatic endothelial cells. Using in vitro assays with blood and lymphatic microvascular endothelial cells (BMVECs and LMVECs, respectively), knockdown of afadin caused elongated cell shapes and disruption of cell-cell junctions among LMVECs, but not BMVECs. In afadin-knockdown LMVECs, enhanced F-actin bundles at the cell periphery and reduced VE-cadherin immunostaining were found, and activation of RhoA was strongly increased compared with that in afadin-knockdown BMVECs. Conversely, inhibition of RhoA activation in afadin-knockdown LMVECs restored the cell morphology. These results indicate that afadin has different effects on blood and lymphatic endothelial cells by controlling the levels of RhoA activation, which may critically regulate the lymphangiogenesis of mouse embryos.

Genetic deletion of afadin causes hydrocephalus by destruction of adherens junctions in radial glial and ependymal cells in the midbrain.

Adherens junctions (AJs) play a role in mechanically connecting adjacent cells to maintain tissue structure, particularly in epithelial cells. The major cell-cell adhesion molecules at AJs are cadherins and nectins. Afadin binds to both nectins and α-catenin and recruits the cadherin-ß-catenin complex to the nectin-based cell-cell adhesion site to form AJs. To explore the role of afadin in radial glial and ependymal cells in the brain, we generated mice carrying a nestin-Cre-mediated conditional knockout (cKO) of the afadin gene. Newborn afadin-cKO mice developed hydrocephalus and died neonatally. The afadin-cKO brain displayed enlarged lateral ventricles and cerebral aqueduct, resulting from stenosis of the caudal end of the cerebral aqueduct and obliteration of the ventral part of the third ventricle. Afadin deficiency further caused the loss of ependymal cells from the ventricular and aqueductal surfaces. During development, radial glial cells, which terminally differentiate into ependymal cells, scattered from the ventricular zone and were replaced by neurons that eventually covered the ventricular and aqueductal surfaces of the afadin-cKO midbrain. Moreover, the denuded ependymal cells were only occasionally observed in the third ventricle and the cerebral aqueduct of the afadin-cKO midbrain. Afadin was co-localized with nectin-1 and N-cadherin at AJs of radial glial and ependymal cells in the control midbrain, but these proteins were not concentrated at AJs in the afadin-cKO midbrain. Thus, the defects in the afadin-cKO midbrain most likely resulted from the destruction of AJs, because AJs in the midbrain were already established before afadin was genetically deleted. These results indicate that afadin is essential for the maintenance of AJs in radial glial and ependymal cells in the midbrain and is required for normal morphogenesis of the cerebral aqueduct and ventral third ventricle in the midbrain.

Pretreatment with ascorbic acid prevents lethal gastrointestinal syndrome in mice receiving a massive amount of radiation.

While bone marrow or stem cell transplantation can rescue bone marrow aplasia in patients accidentally exposed to a lethal radiation dose, radiation-induced irreversible gastrointestinal damage (GI syndrome) is fatal. We investigated the effects of ascorbic acid on radiation-induced GI syndrome in mice. Ascorbic acid (150 mg/kg/day) was orally administered to mice for 3 days, and then the mice underwent whole body irradiation (WBI). Bone marrow transplantation (BMT) 24 h after irradiation rescued mice receiving a WBI dose of less than 12 Gy. No mice receiving 14 Gy-WBI survived, because of radiation-induced GI syndrome, even if they received BMT. However, pretreatment with ascorbic acid significantly suppressed radiation-induced DNA damage in the crypt cells and prevented denudation of intestinal mucosa; therefore, ascorbic acid in combination with BMT rescued mice after 14 Gy-WBI. DNA microarray analysis demonstrated that irradiation up-regulated expressions of apoptosis-related genes in the small intestine, including those related to the caspase-9-mediated intrinsic pathway as well as the caspase-8-mediated extrinsic pathway, and down-regulated expressions of these genes in ascorbic acid-pretreated mice. Thus, pretreatment with ascorbic acid may effectively prevent radiation-induced GI syndrome.