Yasuda Women's University

Iron (Fe) is a transition metal necessary for achieving essential physiological processes throughout the plant lifecycle. In Arabidopsis thaliana, secreting Fe-mobilizing coumarins (FMC) is a key mechanism enabling roots to acquire nonbioavailable Fe present in soils. Here, we unveil the pivotal role played by NRT1/PTR FAMILY 7.2 (NPF7.2) in coumarin secretion by conducting phenotypic analyses of NPF7.2 loss-of-function mutants, NPF7.2 expression-localization analyses and direct transport assay of NPF7.2 protein with coumarin compounds using yeast cells. NPF7.2 loss-of-function impairs coumarin secretion and Fe acquisition in Arabidopsis seedlings, and the corresponding mutants are hypersensitive to Fe deficiency. NPF7.2 protein colocalizes with the main coumarin exporter, PDR9 (PLEIOTROPIC DRUG RESISTANCE PROTEIN 9), in both cortex and epidermis cell layers in root areas where coumarin secretion occurs. A site-specific accumulation of fraxin, a storage form of fraxetin, in root peripheral tissues is disturbed in the mutants under Fe deficiency. When expressed in yeast cells, NPF7.2 protein has an uptake activity for fraxetin and scopoletin, a major FMC and its precursor, respectively. However, fraxin and scopolin, their storage form, are not transported. We propose that NPF7.2 facilitates PDR9-mediated FMC secretion from the epidermis into the rhizosphere by the cellular loading of coumarins from apoplastic spaces, leading to optimal Fe acquisition.

The functions of phosphatase and tensin homolog deleted on chromosome 10 (PTEN), a tumor suppressor, depend on its subcellular localization. At the plasma membrane, PTEN dephosphorylates phosphatidylinositol-3,4,5-triphosphate to inhibit AKT signaling, whereas nuclear PTEN contributes to the maintenance of genomic stability. Fluorescent proteins (FPs) are widely used to assess PTEN's subcellular localization; however, both the intrinsic properties of FPs (e.g., molecular size) and the choice of FP can influence subcellular localization. This study aimed to determine whether FP fusion affects the subcellular localization of PTEN and its mutant forms under conditions involving DNA damage. mCherry typically promotes cytosolic localization of FP-fused PTEN, indicating that FP selection may affect the interpretation of localization data. Furthermore, FP fusion increases the molecular size of the truncated PTEN fragment, which may impede its nuclear import. In comparison, PTEN mutants such as PTENK13R or PTENA4, which predominantly localize to the cytoplasm or nucleus, respectively, show a minimal dependence on the type of FP. Similarly, DNA damage-induced nuclear accumulation of PTEN appears to be independent of the FP type. These findings underscore the importance of carefully considering the effects of FP fusion when investigating the mechanisms regulating the nuclear translocation of PTEN.

Our early study showed the vasoactive effects of soybean lecithin-derived lysophosphatidic acid (LPA). The finding indicates that the oral administration of LPA-rich supplements is beneficial to human health. Our studies have showed five beneficial effects of LPA in the upper digestive systems. First, we detected LPA at high levels in various herbs used in Chinese traditional medicine for the treatment of gastric ulcers, as well as other foods, including various vegetables. Second, we found human mixed saliva to be an LPA-rich biological fluid, suggesting its protective effect on human oral mucosa. Third, LPA levels in gingival crevicular fluid from patients with periodontitis was lower than that in healthy subjects, reinforcing the protective quality of LPA. Fourth, daily topical injections of LPA in rat buccal gingiva reduced the degree of alveolar bone absorption induced by oral bacteria in rats with experimental periodontitis. Fifth, repeated intragastric administration of LPA-rich herb reduced the degrees of gastric ulcer induced by stress (rats) or medication (mouse). Previous findings on the beneficial effects of LPA acting on the lumen side of the lower digestive tracts in mammals are well documented, although results on the harmful effects of LPA on mouse and rats with genetically easy to progress colon cancer are noted. Our studies also showed a novel pathway of LPA generation by lysophospholipase D activity of glycerophosphodiesterase 7 on the lumen side of digestive tracts. These findings suggest that additional research into creative food supplements focusing on LPA as a food factor could be beneficial.

Standard methods for evaluating swallowing function, such as videofluoroscopic swallowing studies and fiberoptic endoscopic evaluation, are invasive and environment-dependent. In our previous study, we confirmed through simultaneous VF measurement that specific waveforms detected by an earphone-type sensor correspond to the timing of soft palate movement during swallowing. The aim of this pilot study was to assess the feasibility and potential applicability of this sensor by examining the temporal relationship between swallowing sounds and sensor waveforms. The earphone-type sensor uses an LED and a phototransistor to detect ear canal movements via reflected infrared light. Six healthy adults swallowed 3 mL of water five times while wearing the sensor in the left ear and a throat microphone on the neck. Swallowing sounds (S I, S II, S III) and waveform points (SA, SB) were analyzed for timing. The mean SA-SB interval was 0.37 ± 0.14 s. SA preceded S I in 52.2% and S II in 100% of cases. No significant difference was observed between SA and S I, whereas SB and S II showed a significant difference (p < 0.001). These findings suggest that the earphone-type sensor waveform reflects the timing of soft palate movement prior to passage of the food bolus into the hypopharynx and esophagus. Although limited by a small sample size, this pilot study provides fundamental evidence supporting the feasibility of noninvasive swallowing assessment using an earphone-type sensor.

The purpose of this study is to investigate Japanese preservice elementary science teachers’ perceptions of environmental education through the theme of biodiversity. The investigation interpreted the array of meanings pre-service teachers construct for environmental phenomena as part of a curriculum addressing the environment. Participants’ experiences, perceptual differences, and intellectual representations regarding environmental education were epistemologically disclosed by a phenomenographic approach. Research was implemented as part of a curriculum that combined environmental education and biodiversity themes with storytelling activities. The data from a structured questionnaire with open-ended questions were analyzed using inductive thematic analysis. The results suggest that the multilayered nature of environmental education can be better understood through the lens of complex environmental issues, such as biodiversity. Findings indicate that preservice teachers highly valued cognitive and belief aspects of values, while having a less comprehensive understanding of both the social and civic engagement and the cultural dimensions of values.

We have undertaken a meta-analysis of international prospective cohorts to quantify the relationship between a family history of fracture and future fracture incidence. The analysis dataset comprised 350,542 men and women from 42 cohorts in 29 countries followed for 2.8 million person-years. We investigated the relationship between family history of hip fracture or any fracture and the risk of any clinical fracture, any osteoporotic fracture, major osteoporotic fracture (MOF), and hip fracture alone using an extended Poisson model in each cohort. Models were adjusted for current age, sex, BMD, and follow-up time. As no difference in influence of family history of fracture was seen between genders, results are presented for men and women combined. A parental history of hip fracture was associated with a higher risk of incident fracture across all fracture outcome categories, with a stronger relationship with future hip fracture (hazard ratios (HR, 95% CI) for hip and MOF 1.37, 1.23-1.52 and 1.19, 1.12-1.27, respectively). Associations were slightly reduced but remained significant when additionally adjusted for BMD and did not vary by baseline offspring age, follow-up time, or parent affected. In a more limited analysis, parental history of any fracture or a sibling history of hip or any fracture showed similar associations to those observed with parental history of hip fracture. A family history of fracture is confirmed as a significant BMD-independent predictor of future fracture risk. While parental hip fracture appears the strongest factor for future hip fracture, a family history of other fractures might be appropriate for inclusion in future iterations of the FRAX tool.

Spheroids are being widely studied as potential building blocks for complex organ engineering, tools for drug screening and cancer study. However, formation time has become the bottleneck of applications due to the need for large‐scale high‐quality spheroids production. Formation time is often dominated by ECM construction and not cell aggregation. Therefore, this study focuses on the influence of ultrasound detachment replacing conventional enzyme detachment on spheroid formation processes. Thanks to cell surface protein preservation in ultrasound detachment, cell aggregation time is reduced while decreasing the formation variabilities. Moreover, it is confirmed that cells are intrinsically more capable of aggregating through enzyme‐free detachment. On top of that, transplantations into rats showed equally successful engraftment properties for enzyme‐free detached cells. Finally, the impact on the real co‐cultured spheroid application was shown to be beneficial through more localized cell groups inside of the spheroids, possibly improving therapeutic effects and vascularization. Through this study, it is proved that ultrasound detachment can replace enzyme detachment without degrading the final spheroid properties but reducing the formation time, and variability and improving robustness and cell distribution. This opens up a new range of applications for better and faster spheroid formation in numerous bioengineering applications.

Mast cells and basophils play important roles in allergic disorders associated with specific antigens and IgE. Crosslinking of the high-affinity IgE receptor (FcεRI) by specific antigens activates several tyrosine kinases, such as Lyn and spleen-associated tyrosine kinase (Syk), resulting in the release of calcium ions (Ca2+) from the endoplasmic reticulum (ER) into the cytoplasm. As Ca2+ release from the ER is essential for the release of pro-inflammatory mediators, ER stress-related molecules, such as inositol-requiring enzyme 1α (IRE1α), may play roles in mast cell and basophil activation. However, the associations between ER stress-related molecules and mast cell and basophil activation remain unclear. In this study, we aimed to investigate the roles of ER stress-related molecules in mast cell and basophil activation. Activation of the IRE1α-spliced form of the X-box binding protein 1 (sXBP1) axis, an ER stress-related pathway, was observed during the antigen-induced activation of mast cells. Moreover, the IRE1α inhibitor, KIRA6, suppressed antigen-induced release of pro-inflammatory mediators from rat basophilic leukemia (RBL)-2H3 cells, bone marrow-derived mast cells (BMMCs), human basophils, and human mast cells at low doses (<1μM). However, to our surprise, IRE1α knockout did not inhibit antigen-induced release of pro-inflammatory mediators. Instead, KIRA6 blocked the antigen-induced activation of Syk by inhibiting kinase activity of Lyn. Additionally, KIRA6 exerted anti-allergic effects in vivo. Overall, our findings suggest that KIRA6 prevents allergic reactions by inhibiting the kinase activity of Lyn via an IRE1α-independent pathway.