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Background The transient receptor potential vanilloid 4 (TRPV4), a thermo-sensitive stretch-activated cation channel, is expressed in the skin stratified squamous epithelium, contributing to the acquisition of barrier function. Similarly, functional TRPV4 may be located in the stratified squamous epithelial lining of the esophagus, being involved in the pathogenesis of gastroesophageal reflux disease (GERD). Here we investigated the expression of TRPV4 in the mouse esophageal epithelium. Methods TRPV4 expression at the mRNA and protein levels was examined by reverse transcription-polymerase chain reaction (RT-PCR), in situ hybridization, and immunohistochemistry. A calcium imaging technique and ATP assay were used to evaluate the functionality of TRPV4 in freshly isolated esophageal epithelial cells. Key Results Transcripts and proteins encoding TRPV4 were colocalized in the basal and intermediate layers of the esophageal epithelium. Both 4α-phorbol 12,13- didecanoate (4α-PDD), a selective agonist for TRPV4, and hypo-osmolar solution (160 mOsm) elevated the intracellular calcium concentration ([Ca2+]i) in a subset of the isolated cells (70%). These [Ca2+]i increases were potently inhibited by ruthenium red (RuR), a TRPV4 channel antagonist, and were suppressed by extracellular protons (pH 5.0). Finally, application of 4α-PDD evoked ATP release in primary esophageal epithelial cells. Conclusions & Inferences Acid-sensitive TRPV4 channels were mainly expressed in the esophageal epithelial cells of the basal and intermediate layers. Direct exposure of TRPV4-expressing cells to gastric acid, as would occur in cases of GERD, could influence their cellular functions, possibly aggravating the disease state. [ABSTRACT FROM AUTHOR]

The esophageal epithelium has sensory properties that enable it to sustain normal barrier function. Transient receptor potential vanilloid 4 (TRPV4) is a Ca2+-permeable channel that is activated by extracellular hypotonicity, polyunsaturated fatty acids, phorbol esters, and elevated temperature. We found that TRPV4 is expressed in both human esophageal tissue and in HET-1A cells, a human esophageal epithelial cell line. Specific activation of TRPV4 by the phorbol ester 4α-phorbol 12,13-didecanoate (4α-PDD) increased intracellular Ca2+ in a subset of HET-1A cells. Elevated temperature strongly potentiated this effect at low concentrations of 4α-PDD, and all of the responses were inhibited by the TRPV antagonist ruthenium red. TRPV4 activation differentially affected cell proliferation and cell viability; HET-1A cell proliferation was increased by 1 μM 4α-PDD, whereas higher concentrations (10 μM and 30 μM) significantly decreased cell viability. Transient TRPV4 activation triggered ATP release in a concentration-dependent manner via gap-junction hemichannels, including pannexin 1 and connexin 43. Furthermore, TRPV4 activation for 24 h did not increase the production of interleukin 8 (IL-8) but reduced IL-1β-induced IL-8 production. Small-interference RNA targeted to TRPV4 significantly attenuated all of the 4α-PDD-induced responses in HET-1A cells. Collectively, these findings suggest that TRPV4 is a novel regulator of Ca2+-dependent signaling pathways linked to cell proliferation, cell survival, ATP release, and IL-8 production in human esophageal epithelial cells. [ABSTRACT FROM AUTHOR]

Conclusion: Immunohistochemical detection of Reelin in granular cells and disabled-1 in cochlear nucleus suggests a possible Reelin signaling pathway in mature rat cochlear nucleus. Materials and Methods: Six-week-old Wister rats were used throughout this study. The expression of reelin and disabled-1 were studied by using in situ hybridization technique and immunohistochemistry. Results: Reelin mRNA expression was observed in granular cell layer of dorsal cochlear nucleus. Immunohistochemistry using anti-reelin monoclonal antibodies confirmed reelin expression in granule cells at protein level. We also examined disabled-1 expression in cochlear nucleus and observed positive immunoreactivity in both ventricular and dorsal cochlear nucleus. In the dorsal cochlear nucleus, fusiform and cartwheel cells were labeled. In the ventricular cochlear nucleus, relatively large cells were labeled with anti-disabled-1 polyclonal antibody but the subtypes of disabled-1 positive cells could not be identified. [ABSTRACT FROM AUTHOR]

To clarify the effect of aerial insecticide spraying on pine wilt disease, pine wilt disease impacts was surveyed in pine stands and the damage evaluated using a logistic model. Eleven quadrats were established randomly in stands with or without aerial spraying. Aerial spraying alone did not entirely prevent the disease. Average annual mortality was lower in stands with aerial spraying than in stands without aerial spraying. Aerial spraying slowed the progress of pine wilt disease, as measured by the disease progress index. The biomass of live pine trees decreased with increased damage in stands without aerial spraying, whereas biomass was maintained in stands with aerial spraying. However, the relative basal area showed that succession of pine forests to forests dominated by other species was accelerated even in stands with aerial insecticide spraying. [ABSTRACT FROM AUTHOR]

Purpose: To establish an ultra-high dose rate (UHDR) radiation system using a synchrotron proton beam accelerator and to compare the effects by irradiation positions on cultured cells and chick embryos., Methods and Materials: Protons for UHDR were obtained by applying high-frequency power at much higher levels than usual to extract all protons within approximately 50 ms. Subsequently, monitoring with a Faraday cup was performed immediately after synchrotron extraction and the waveform was adjusted accordingly. Four cultured tumor lines, two normal cell lines, and chick embryos were used. Ultra-high dose-rate radiation (UHDR-RT) at 6-18 Gy (200-300 Gy/s, single exposure) and conventional dose-rate radiation (Conv-RT) at 6-18 Gy (3 Gy/s) were administered to the 1-cm spread-out Bragg peak (SOBP) and the plateau region preceding SOBP. Following irradiation, disparities in cell growth rates and cell cycle progression were assessed, and cell survival was evaluated via colony assay. Chick embryos were also examined for survival., Results: UHDR-RT was achieved at a range of 40 to 800 Gy/s, encompassing both plateau and peak phases. In vitro studies demonstrated similar cell-killing effects between UHDR-RT and Conv-RT in cancer cells. Significant apoptotic effects and G2 arrest were observed during the cell cycle under peak UHDR-RT conditions. The FLASH effect was not observed in normal single cells under normal atmospheric conditions. Stronger cell-killing effects were noted in V79 spheroids exposed to peak UHDR-RT than peak Conv-RT. Moreover, in chick embryos, an increase in survival rate, indicative of the FLASH effect, was observed., Conclusions: The FLASH effect was also achieved with UHDR-RT using a synchrotron proton beam accelerator in chick embryos. The cell-killing effects in cancer cells were higher with peak UHDR-RT which may be due to the higher linear energy transfer at the SOBP., Competing Interests: Declaration of competing interest Masumi Umezawa and Masashi Yamada are the permanent employees of Hitachi High-Tech Corporation. The authors declare this does not alter their adherence to IJROBP policies on sharing data and materials., (Copyright © 2024. Published by Elsevier Inc.)

Background: Neuronal dysfunction is implicated in the pathophysiology of asthma and functional dyspepsia (FD). However, the relationship between these diseases remains unclear., Objective: This study aimed to clarify the clinical implications of comorbid FD in asthma and to explore the unified pathway between asthma and FD by focusing on airway neuronal dysfunction., Methods: Clinical indices and biomarkers, including capsaicin cough sensitivity (C-CS), were compared between patients with asthma with and without FD. C-CS was determined on the basis of capsaicin concentration that induced at least 2 coughs (C2) or 5 coughs (C5). Additionally, the associations of airway inflammation with airway innervation and gastrointestinal motility were evaluated in mouse models of type 2 airway inflammation., Results: Patients with asthma with FD had worse asthma control and cough severity and lower C2 and C5 thresholds than those without FD. The severity of FD symptoms was negatively correlated with C2 and C5 thresholds. FD and poor asthma control were predictors of heightened C-CS (defined as C5 ≤ 2.44 μmol) in asthma. A mouse model of papain-induced airway inflammation developed airway hyperinnervation and gastrointestinal dysmotility, and both pathologies were ameliorated by an anti-IL-33 antibody. Moreover, papain-induced gastrointestinal dysmotility was mitigated by silencing the airway sensory neurons using QX-314, a sodium channel blocker. Furthermore, sputum IL-33 levels were significantly elevated in patients with asthma with FD or heightened C-CS compared to their counterparts., Conclusion: FD is significantly associated with airway neuronal dysfunction in asthma. IL-33-mediated airway neuronal dysfunction may contribute to the interaction between asthma and FD., Competing Interests: Disclosure statement Supported in part by a research grant from MSD Life Science Foundation, Public Interest Incorporated Foundation (RA-020 to Y.K.), a research grant from the Japanese Respiratory Society Research Grants Program (to K.I.), and a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology (MEXT; 24K11373 to Y.K.). Disclosure of potential conflict of interest: K. Ito reports speaker honoraria from AstraZeneca. Y. Kanemitsu reports research grants from Novartis, MSD, and Sanofi; and honoraria for lectures, presentations, and educational events from GSK, AstraZeneca, Kyorin, Sanofi, Novartis, and Zeria. K. Fukumitsu reports research grants from Novartis, GSK, and Daiichi Sankyo. S. Fukuda reports speaker honoraria from AstraZeneca. T. Uemura reports honoraria for lectures and presentations from AstraZeneca, MSD, Novartis, and Chugai. H. Ohkubo reports research grants and honoraria for lectures from Boehringer Ingelheim. A. Niimi reports honoraria for lectures and presentations from AstraZeneca, Kyorin, Novartis, GSK, Sanofi; and personal fees for participating on advisory boards from AstraZeneca, MSD, Kyorin, and Bayer. The rest of the authors declare that they have no relevant conflicts of interest., (Copyright © 2024 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

The number of elderly patients with acute decompensated heart failure (ADHF) is increasing, and it is often difficult to treat. This study aimed to evaluate the efficacy and safety of using tolvaptan early after hospitalization in elderly patients with ADHF and the prognosis one year after hospitalization. This study enrolled 185 patients with ADHF who were admitted for the first time. Tolvaptan was administered within 24 h after admission. These patients were assigned to two groups: over 80 years old ( n = 109) and under 80 years old ( n = 76). There were no significant differences between the two groups in the occurrence of MACCE within one year (25% vs. 20%, p = 0.59). All-cause mortality was significantly higher in the over-80 group (12% vs. 2%, p = 0.01). There were no significant differences in the incidence of worsening renal failure (11% vs. 7%, p = 0.46) and hypernatremia (5% vs. 9%, p = 1.0), and in the duration of hospitalization (19.2 days vs. 18.8 days, p = 0.8). Tolvaptan might be effective and safe in elderly patients with ADHF, and there was no difference in the incidence of MACCE within one year.

Objectives: Vascular endothelial growth factor-A (VEGF-A) plays a leading role in angiogenesis and pain hypersensitivity in cancer and chronic pain. It is not only induced by ischemic conditions but is also highly correlated with proalgesic cytokines, both of which are prominent in inflammatory muscle pain. However, the molecular basis of the involvement of VEGF-A in muscle pain remains unknown., Methods: In the present study, we performed behavioral and pharmacological analyses to determine the possible involvement of VEGF-A in the development of inflammatory muscle pain and the associated signal transduction pathway., Results: Unilateral intramuscular injection of carrageenan, a classical model of inflammatory muscle pain, increased VEGF-A gene expression in the tissues surrounding the injection site. Intramuscular administration of recombinant VEGF-A165 on the same side induced cutaneous mechanical hyperalgesia during the acute and subacute phases. The application of a specific VEGFR1 antibody on the same side significantly reduced the mechanical hyperalgesia induced by carrageenan or VEGF-A165 injection, whereas both a VEGFR2-neutralizing antibody and a VEGFR2 antagonist showed limited effects. Local preinjection of capsazepine, a transient receptor potential vanilloid 1 (TRPV1) antagonist, also inhibited VEGF-A165-induced hyperalgesia. Finally, intramuscular VEGF-A165-induced mechanical hyperalgesia was not found in TRPV1 knockout mice during the subacute phase., Conclusions: These findings suggest that inflammatory stimuli increase interstitial VEGF-A165, which in turn induces cutaneous mechanical pain via the VEGFR1-mediated TRPV1 nociceptive pathway during inflammatory muscle pain. VEGFR1 could be a novel therapeutic target for inflammation-induced muscle pain., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

HDL are dynamic transporters of diverse molecular cargo and play critical roles in lipid metabolism and inflammation. We have previously reported that HDL transport both host and nonhost small RNAs (sRNA) based on quantitative PCR and sRNA sequencing approaches; however, these methods require RNA isolation steps which have potential biases and may not isolate certain forms of RNA molecules from samples. HDL have also been reported to accept functional sRNAs from donor macrophages and deliver them to recipient endothelial cells; however, using PCR to trace HDL-sRNA intercellular communication has major limitations. The present study aims to overcome these technical barriers and further understand the pathways involved in HDL-mediated bidirectional flux of sRNAs between immune cells. To overcome these technical limitations, SYTO RNASelect, a lipid-penetrating RNA dye, was used to quantify a) overall HDL-sRNA content, b) bidirectional flux of sRNAs between HDL and immune cells, c) HDL-mediated intercellular communication between immune cells, and d) HDL-mediated RNA export changes in disease. Live cell imaging and loss-of-function assays indicate that the endo-lysosomal system plays a critical role in macrophage storage and export of HDL-sRNAs. These results identify HDL as a substantive mediator of intercellular communication between immune cells and demonstrate the importance of endocytosis for recipient cells of HDL-sRNAs. Utilizing a lipid-penetrating RNA-specific fluorescence dye, we were able to both quantify the absolute concentration of sRNAs transported by HDL and characterize HDL-mediated intercellular RNA transport between immune cells., Competing Interests: Conflict of interest No author reports a financial interest with respect to the work outlined in this document., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

Fibroblasts of different origins are known to possess stromal memory after inflammatory episodes. However, there are no studies exploring human lung fibroblast memory which may predict a subsequent inflammatory response in chronic respiratory diseases and COVID-19. MRC-5 and HF19 human lung fibroblast cell lines were treated using different primary and secondary stimulus combinations: TNFα-WD-TNFα, Poly (I:C)-WD-TNFα, TNFα-WD-Poly (I:C), or LPS-WD-TNFα with a 24-h rest period (withdrawal period; WD) between the two 24-h stimulations. TLR3 and NF-κB inhibitors were used to determine pathways involved. The effect of SARS-Cov-2 spike protein to inflammatory response of lung fibroblasts was also investigated. mRNA expressions of genes and IL6 release were measured using qRT-PCR and ELISA, respectively. Statistical significance was determined by using one- or two-way ANOVA, followed by Bonferroni's post hoc analysis for comparison of multiple groups. Preexposure with Poly (I:C) significantly increased TNFα-induced IL6 gene expression and IL6 release in both cell lines, while it affected neither gene expressions of IL1B , IL2 , IL8 , and MMP8 nor fibrosis-related genes: ACTA2 , COL1A1 , POSTN , and TGFB1 . Inhibition of TLR3 or NF-κB during primary stimulation significantly downregulated IL6 release. Simultaneous treatment of MRC-5 cells with SARS-CoV-2 spike protein further increased TNFα-induced IL6 release; however, preexposure to Poly (I:C) did not affect it. Human lung fibroblasts are capable of retaining inflammatory memory and showed an augmented response upon secondary exposure. These results may contribute to the possibility of training human lung fibroblasts to respond suitably on inflammatory episodes after viral infection., Competing Interests: The following authors received research grants and personal fees outside the submitted work: YK received research grants from Novartis Pharma, MSD, Sanofi, and personal fees from GSK, Novartis Pharma, AstraZeneca, Sanofi, and Kyorin. KF received research grants from Novartis Pharma and GSK. SF received personal fees from AstraZeneca and Eli Lilly. HO received a research grant from Boehringer Ingelheim. KM received personal fees from Pfizer and Chugai Pharmaceutical. TO reports personal fees from AstraZeneca, Eli Lilly Japan, Taiho Pharmaceutical, Pfizer, Chugai Pharmaceutical, MSD, Daiichi Sankyo, and Asahi Kasei Pharma, as well as research grants and personal fees from Kyowa Hakko Kirin, Boehringer Ingelheim, Ono Pharmaceutical, and Novartis. AN reports personal fees from Astellas, AstraZeneca, Kyorin, GSK, MSD, Shionogi, Bayer, Sanofi, Taiho, and Boehringer Ingelheim, and research grants from Astellas, Kyorin, Boehringer Ingelheim, Novartis, MSD, Daiichi Sankyo, Taiho, Teijin, Ono, Takeda, and Sanofi Pharmaceutical. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Yap, Ueda, Kanemitsu, Takeda, Fukumitsu, Fukuda, Uemura, Tajiri, Ohkubo, Maeno, Ito, Oguri, Ugawa and Niimi.)

SLC26A4 is a known iodide transporter, and is localized at the apical membrane of thyrocytes. Previously, we reported that SLC26A7 is also involved in iodide transport and that Slc26a7 is a novel causative gene for congenital hypothyroidism. However, its detailed role in vivo remains to be elucidated. We generated mice that were deficient in Slc26a7 and Slc26a4 to delineate differences and associations in their roles in iodide transport. Slc26a7 -/- mice showed goitrous congenital hypothyroidism and mild growth failure on a normal diet. Slc26a7 -/- mice with a low iodine environment showed marked growth failure. In contrast, Slc26a4 -/- mice showed no growth failure and hypothyroidism in the same low iodine environment. Double-deficient mice showed more severe growth failure than Slc26a7 -/- mice. RNA-seq analysis revealed that the number of differentially expressed genes (DEGs) in Slc26a7 -/- mice was significantly higher than that in Slc26a4 -/- mice. These indicate that SLC26A7 is more strongly involved in iodide transport and the maintenance of thyroid function than SLC26A4., (© 2022. The Author(s).)

Specific amino acid substitutions in degenerin mechano-gated channels (DEGs) of C. elegans convert these channels into constitutively active mutants that induce the degeneration of neurons where DEGs are expressed. Acid-sensing ion channel-2a (ASIC2a), a proton-gated cation channel predominantly expressed in central neurons, is a mammalian ortholog of DEGs, and it can remain unclosed to be cytotoxic once the same mutations as the DEG mutants are introduced into its gene. Here we show that heterozygous transgenic (Tg) rats expressing ASIC2a-G430F (ASIC2a G430F ), the most active form of the gain-of-function mutants, under the control of the intrinsic ASIC2a promoter exhibited marked cerebellar maldevelopment with mild whole-brain atrophy. The Tg rats were small and developed an early-onset ataxic gait, as evidenced by rotarod and footprint tests. The overall gross-anatomy of the Tg brain was normal just after birth, but a reduction in brain volume, especially cerebellar volume, gradually emerged with age. Histological examination of the adult Tg brain revealed that the cell-densities of cerebellar Purkinje and granule cells were markedly reduced, while the cytoarchitecture of other brain regions was not significantly altered. RT-PCR and immunoblot analyses demonstrated that ASIC2a G430F transcripts and proteins were already present in various regions of the neonatal Tg brain before the deforming cerebellum became apparent. These results suggest that, according to the spatiotemporal pattern of the wild-type (WT) ASIC2a gene expression, the ASIC2a G430F channel induced lethal degeneration in Tg brain neurons expressing both ASIC2a G430F and ASIC2a channels., Competing Interests: Declaration of competing interest The authors declare no competing financial interests., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objectives: To investigate the efficacy and safety of larger valve sizing beyond the commercially recommended annular range in transcatheter aortic valve replacement (TAVR) with balloon-expandable transcatheter heart valve (THVs)., Background: The clinical implications of larger balloon-expandable THV implantation with underfilling are poorly evaluated., Methods: This retrospective study included 692 consecutive patients who underwent TAVR with SAPIEN3. A total of 271 patients who underwent SAPIEN 3 implantation were analyzed based on three border zones (Zone 1: 300-345 mm 2 , 23 vs. 20 mm; Zone 2: 400-430 mm 2 , 26 vs. 23 mm; Zone 3: 500-546 mm 2 , 29 vs. 26 mm). The primary endpoint was the effective orifice area (EOA) assessed by echocardiography at 1 year, and secondary endpoints were a 30-day mortality rate, procedural complications during TAVR, and a composite of death from any cause and heart failure requiring rehospitalization at 1 year., Results: At 1-year follow-up, the EOA in the larger valve groups was greater than that in the recommended valve group in each zone (Zone 1: 1.45 ± 0.03 vs. 1.06 ± 0.06 cm 2 , p < 0.001; Zone 2: 1.83 ± 0.05 vs. 1.41 ± 0.05 cm 2 , p < 0.001; Zone 3: 1.93 ± 0.07 vs. 1.69 ± 0.07 cm 2 , p = 0.02). No significant difference in the secondary endpoint was observed in any of the zones., Conclusions: Implantation of the out-of-range larger SAPIEN 3 THVs with underfilling was associated with greater EOA at the 1-year follow-up and feasible in the selected patients., (© 2022 Wiley Periodicals LLC.)

Elevated circulating lipoprotein(a) levels are associated with an increased risk of cardiovascular events. We reported that early initiation of evolocumab, a proprotein convertase subtilisin/kexin type 9 inhibitor, in addition to a statin substantially reduced the lipoprotein(a) levels in patients with acute myocardial infarction (AMI) after primary percutaneous coronary intervention (PCI). This sub-analysis sought to investigate the effect of evolocumab on lipoprotein(a) based on baseline lipoprotein(a) levels and characteristics. This study was a prespecified analysis of a randomized controlled trial that enrolled 102 patients who underwent primary PCI for AMI. Patients received pitavastatin (2 mg/day) alone or pitavastatin and evolocumab 140 mg subcutaneously within 24 h and 2 weeks after the index PCI. The evolocumab group showed significantly suppressed lipoprotein(a) levels in patients with baseline lipoprotein(a) levels of ≤10 mg/dL, 10 < lipoprotein(a) ≤ 20 mg/dL, and >20 mg/dL compared with the control group, as well as similar reductions in lipoprotein(a) levels in all patient subgroups. Among these subgroups, evolocumab tended to show more favorable effects in patients with diabetes mellitus. In AMI patients, early initiation of evolocumab therapy within 24 h of primary PCI suppressed the increase in lipoprotein(a) levels within 4 weeks, regardless of baseline levels and characteristics.

Dual-energy computed tomography (DECT) is a promising technique for the assessment of the lung perfused blood volume (LPBV) in the lung parenchyma. This study was performed to compare the LPBV by DECT of patients with pulmonary hypertension (PH) and controls and to evaluate the association between the LPBV and the perfusion ratio derived by lung perfusion scintigraphy. This study involved 45 patients who underwent DECT (25 patients with PH and 20 controls). We measured the total LPBV and distribution of the LPBV in each lung. The total LPBV was significantly lower in the PH group than the control group (38 ± 9 vs. 45 ± 8 HU, p = 0.024). Significant differences were observed between the LPBV of the upper lung of the PH and control groups (34 ± 10 vs. 47 ± 10, p = 0.021 and 37 ± 10 vs. 47 ± 8, p < 0.001). A significant correlation was observed between the LPBV and the lung perfusion scintigraphy. A lower total LPBV and lower LPBV of the upper lung as detected by DECT might be specific findings of PH.

To produce water-stable Ni-rich lithium nickel cobalt aluminum oxides (LiNi x Co y Al 1- x - y O 2 , x > 0.85, NCAs), the formation of trilithium phosphate (Li 3 PO 4 )-coated layers on the NCA surfaces was attempted through the use of a surface reaction in a mixture of ethanol and water and a post-heat treatment at 350 and 400 °C. Based on the results of X-ray photoelectron spectroscopy (XPS), the coated layers consisted of nickel phosphate (Ni 3 (PO 4 ) 2 ) and Li 3 PO 4 . The coated NCA surface could have sufficient water stability to maintain the cathode performance in a water slurry for 1 day. In addition, the coated layers formed on the NCA surfaces did not block Li + -ion transfer through the Ni 3 (PO 4 ) 2 /Li 3 PO 4 -coating layers and enhanced the high-rate discharge performance., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

In addition to the taste receptors corresponding to the six basic taste qualities-sweet, salty, sour, bitter, umami, and fatty-another type of taste receptor, calcium-sensing receptor (CaSR), is found in taste-bud cells. CaSR is called the ' kokumi ' receptor because its agonists increase sweet, salty and umami tastes to induce ' koku ', a Japanese word meaning the enhancement of flavor characters such as thickness, mouthfulness, and continuity. Koku is an important factor for enhancing food palatability. However, it is not well known whether other kokumi -receptors and substances exist. Here, we show that ornithine (L-ornithine but not D-ornithine) at low concentrations that do not elicit a taste of its own, enhances preferences to sweet, salty, umami, and fat taste solutions in mice. Increased preference to monosodium glutamate (MSG) was the most dominant effect. Antagonists of G-protein-coupled receptor family C group 6 subtype A (GPRC6A) abolished the additive effect of ornithine on MSG solutions. The additive effects of ornithine on taste stimuli are thought to occur in the oral cavity, and are not considered post-oral events because ornithine's effects were confirmed in a brief-exposure test. Moreover, the additive effects of ornithine and the action of the antagonist were verified in electrophysiological taste nerve responses. Immunohistochemical analysis implied that GPRC6A was expressed in subsets of type II and type III taste cells of mouse circumvallate papillae. These results are in good agreement with those reported for taste modulation involving CaSR and its agonists. The present study suggests that ornithine is a kokumi substance and GPRC6A is a newly identified kokumi receptor.

To investigate the effect of reduced snow cover on fine root dynamics in a cool-temperate forest in northern Japan because of decreases in snowfall at high latitudes due to global warming, we monitored root length, production, and mortality before and after snow removal with an in-ground root scanner. We measured root dynamics of both overstory deciduous oak (Quercus crispula) and understory evergreen dwarf bamboo (Sasa nipponica), the two major species in the forest. Snow removal advanced the timing of peak root production by a month both in total and in Sasa, but not in oak. There was a significant interaction between snow removal and plant form on root production; this indicates that enhanced Sasa root production following snow removal might increase its ability to compete with oak. In contrast, snow removal did not enhance root mortality, suggesting that the roots of these species tolerate soil freezing. The earlier snow disappearance in the snow removal plot expanded the growing season in Sasa. We speculate that this change in the understory environment would advance the timing of root production by Sasa by extending the photosynthetic period in spring. We propose that different responses of root production to reduced snow cover between the two species would change the competitive interactions of overstory and understory vegetation, influencing net primary production and biogeochemistry (e.g., carbon and nitrogen cycles) in the forest ecosystem.

Background: Little is known on the role of transient receptor potential ankyrin 1 (TRPA1) in fibroblast-myofibroblast transition (FMT) that can lead to airway remodeling which is a major problem for severe asthma and fibrosis. Thus, this study investigated the effect of TRPA1 modulators on transforming growth factor beta 1(TGF-β1) -treated lung fibroblasts., Methods: MRC-5 cells were preincubated with TGF-β1 for 24 h. TRPA1 agonist or antagonist were added and further incubated for 24 h. The changes in TRPA1 and alpha-smooth muscle actin (α-SMA) expressions by stimuli were evaluated using qRT-PCR, western blot and immunohistochemical analyses. Statistical significance was determined by using one- or two-way ANOVA, followed by Bonferroni's post hoc analysis for comparison of multiple groups and paired 2-tailed Student's t-test between 2 groups., Results: MRC-5 cells treated by TGF-β1 significantly upregulated α-SMA mRNA expressions (P < 0.01), but downregulated TRPA1 gene expression (P < 0.001). Post-treatment of TRPA1 activator, allyl isothiocyanate (AITC), after TGF-β1 significantly downregulated the α-SMA gene induction (P < 0.01 at 24 h), protein expression (P < 0.05) and immunoreactivity with stress fibers (P < 0.05). On the other hand, TRPA1 antagonist HC-030031 did not prevent this effect, and instead tended to facilitate the suppressive effect of AITC when co-stimulated. AITC significantly increased phosphorylated- extracellular signal-regulated kinase (ERK) 1/2 and heme oxygenase (HO)-1 protein expressions (P < 0.05) in TGF-β1-treated cells. Combined inhibition with ERK1/2 mitogen-activated protein kinase (MAPK) and nuclear factor erythroid 2-related factor (NRF2) almost completely reversed AITC-induced α-SMA suppression (P < 0.05). Dexamethasone was not able to inhibit the upregulated α-SMA induction by TGF-β1. However, AITC improved dexamethasone-insensitive myodifferentiation in the presence of the corticosteroid (P < 0.01)., Conclusion: We found that AITC exerts protective effect on TGF-β1-induced α-SMA induction by activating ERK1/2 MAPK and NRF2/HO-1 pathways in lung fibroblasts. It also overcomes corticosteroids insensitivity in TGF-β1-induced α-SMA induction. TRPA1 antagonist modulates the suppressive effect, but not prevent it. AITC and TRPA1 antagonist may be therapeutic agents in treating chronic respiratory diseases.