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The skin is a protective interface between the internal organs and environment and functions not only as a physical barrier but also as an immune organ. However, the immune system in the skin is not fully understood. A member of the thermo-sensitive transient receptor potential (TRP) channel family, TRPM4, which acts as a regulatory receptor in immune cells, was recently reported to be expressed in human skin and keratinocytes. However, the function of TRPM4 in immune responses in keratinocytes has not been investigated. In this study, we found that treatment with BTP2, a known TRPM4 agonist, reduced cytokine production induced by tumor necrosis factor (TNF) α in normal human epidermal keratinocytes and in immortalized human epidermal keratinocytes (HaCaT cells). This cytokine-reducing effect was not observed in TRPM4-deficient HaCaT cells, indicating that TRPM4 contributed to the control of cytokine production in keratinocytes. Furthermore, we identified aluminum potassium sulfate, as a new TRPM4 activating agent. Aluminum potassium sulfate reduced Ca2+ influx by store-operated Ca2+ entry in human TRPM4-expressing HEK293T cells. We further confirmed that aluminum potassium sulfate evoked TRPM4-mediated currents, showing direct evidence for TRPM4 activation. Moreover, treatment with aluminum potassium sulfate reduced cytokine expression induced by TNFα in HaCaT cells. Taken together, our data suggested that TRPM4 may serve as a new target for the treatment of skin inflammatory reactions by suppressing the cytokine production in keratinocytes, and aluminum potassium sulfate is a useful ingredient to prevent undesirable skin inflammation through TRPM4 activation.

形態: カラー図版あり, Physical characteristics: Original contains color illustrations, Accepted: 2018-12-08, 資料番号: PA1920026000

形態: カラー図版あり, Physical characteristics: Original contains illustrations, Accepted: 2019-07-28, 資料番号: PA2020003000

Maternal–fetal transport of calcium (Ca2+) is important for bone mineralization in fetal development. Insufficient Ca2+ transport causes transient neonatal hyperparathyroidism (TNHP). Transient receptor potential cation channel, subfamily V, member 6 (TRPV6), has been found to play an important role in the active transport of Ca2+ through the placenta. Recently, TRPV6 gene was found to be the gene responsible for TNHP with severe skeletal undermineralization. To date, only seven cases of TNHP caused by TRPV6 recessive mutations have been reported. We present a case of TNHP caused by TRPV6 gene mutations. A female newborn was hospitalized because of respiratory distress. Marked undermineralization of the skeleton was observed in X-ray imaging. Laboratory examination revealed markedly high PTH and absence of hypercalcemia along with vitamin D deficiency. Her twin brother presented with almost no symptoms. Maternal laboratory findings indicated normocalcemia, but vitamin D deficiency with a high PTH level for the lactation period was observed. We initially diagnosed the patient as having secondary hyperparathyroidism because of maternal vitamin D deficiency. Nevertheless, the reasons underlying the discordant clinical manifestations between the twin siblings remained unclear. Our analysis of TRPV6 gene clarified that the patient had compound heterozygote mutations, which were reported previously (p.Ile223Thr and p.Gly428Arg). Pathologic mutations in TRPV6 gene were not detected in the other sibling. The clinical symptoms in the patient were transient: they resolved during infancy. TNHP caused by TRPV6 gene mutations is a unique disease in terms of its transient pathology in utero and relief after birth.

The stratum corneum (SC), the outermost epidermal layer, consists of nonviable anuclear keratinocytes, called corneocytes, which function as a protective barrier. The exact modes of cell death executed by keratinocytes of the upper stratum granulosum (SG1 cells) remain largely unknown. Here, using intravital imaging combined with intracellular Ca(2+)- and pH-responsive fluorescent probes, we aimed to dissect the SG1 death process in vivo. We found that SG1 cell death was preceded by prolonged (∼60 min) Ca(2+) elevation and rapid induction of intracellular acidification. Once such intracellular ionic changes were initiated, they became sustained, irreversibly committing the SG1 cells to corneocyte conversion. Time-lapse imaging of isolated murine SG1 cells revealed that intracellular acidification was essential for the degradation of keratohyalin granules and nuclear DNA, phenomena specific to SC corneocyte formation. Furthermore, intravital imaging showed that the number of SG1 cells exhibiting Ca(2+) elevation and the timing of intracellular acidification were both tightly regulated by the transient receptor potential cation channel V3. The functional activity of this protein was confirmed in isolated SG1 cells using whole-cell patch-clamp analysis. These findings provide a theoretical framework for improved understanding of the unique molecular mechanisms underlying keratinocyte-specific death mode, namely corneoptosis.

Masking is a direct behavioral response to environmental changes and plays an important role in the temporal distribution of activity. However, the mechanisms responsible for masking remain unclear. Here we identify thermosensors and a possible neural circuit regulating temperature-dependent masking behavior in mice. Analysis of mice lacking thermosensitive transient receptor potential (TRP) channels (Trpv1/3/4 and Trpm2/8) reveals that temperature-dependent masking is impaired in Trpm2- and Trpm8-null mice. Several brain regions are activated during temperature-dependent masking, including the preoptic area (POA), known as the thermoregulatory center, the suprachiasmatic nucleus (SCN), which is the primary circadian pacemaker, the paraventricular nucleus of the thalamus (PVT), and the nucleus accumbens (NAc). The POA, SCN, PVT are interconnected, and the PVT sends dense projections to the NAc, a key brain region involved in wheel-running activity. Partial chemical lesion of the PVT attenuates masking, suggesting the involvement of the PVT in temperature-dependent masking behavior.

We present three-scale modeling of multilayered structures consisting of heterogeneous layers. The presented laminated model is not based on the so-called lamination theory or assumption related to the theories. The framework is based on the multiscale seamless-domain method and homogenization theory. First, we conduct homogenization analysis of the heterogeneous laminate and regard it as being composed of the homogenized anisotropic layers (i.e., the microscopic analysis). Second, we analyze the laminate using the multiscale seamless-domain method (i.e., the mesoscopic and macroscopic analyses). We present numerical examples of heat conduction and elastic deformation for fiber-reinforced composite laminates. In all examples, the proposed multilayered models represented by a small number of points provided solutions as accurate as those of ordinary finite-element models having many nodes.

Carbon-fiber-reinforced polymer (CFRP) composites are used in aerospace and automobile structures. For many CFRP structures, mechanical metallic fasteners are adopted. In internal structures such as a wing box, damage to CFRP structures around the fastener holes is difficult to see. A simple method of finding damage around fastener holes is thus required for CFRP structures. This study applies self-sensing time-domain reflectometry to detect bearing failure around fastener holes of CFRP structures. In a previous paper, the effect of fasteners was minimized when the micro-strip line (MSL) was placed apart from the fasteners. This study numerically and experimentally investigates the peeling of glass-fiber-reinforced polymer (GFRP) insulator. A bearing failure results in embossing at the edge of a fastener hole. The embossing produces a wedge that causes the peeling of GFRP, generating a gap between the GFRP and CFRP. The gap strongly affects the characteristic impedance of the MSL.

Purpose: Calcium entry channels in the plasma membrane are thought to play a major role in maintaining cellular Ca2+ levels, crucial for growth and survival of normal and cancer cells. The calcium-selective channel TRPV6 is expressed in prostate, breast, and other cancer cells. Its expression coincides with cancer progression, suggesting that it drives cancer cell growth. However, no specific inhibitors for TRPV6 have been identified thus far. Methods: To develop specific TRPV6 inhibitors, we synthesized molecules based on the lead compound TH-1177, reported to inhibit calcium entry channels in prostate cancer cells in vitro and in vivo. Results: We found that one of our compounds (#03) selectively inhibited TRPV6 over five times better than TRPV5, whereas TH-1177 and the other synthesized compounds preferentially inhibited TRPV5. The IC50 value for growth inhibition by blocking endogenous Ca2+ entry channels in the LNCaP human prostate cancer cell line was 0.44 ± 0.07 μM compared to TH-1177 (50 ± 0.4 μM). Conclusions: These results suggest that compound #03 is a relatively selective and potent inhibitor for TRPV6 and that it is an interesting lead compound for the treatment of prostate cancer and other cancers of epithelial origin.

Transient neonatal hyperparathyroidism (TNHP) is etiologically a heterogeneous condition. One of the etiologies is an insufficient maternal-fetal calcium transport through the placenta. We report six subjects with homozygous and/or compound-heterozygous mutations in the gene encoding the transient receptor potential cation channel, subfamily V, member 6 (TRPV6), an epithelial Ca2+-selective channel associated with this condition. Exome sequencing on two neonates with skeletal findings consistent with neonatal hyperparathyroidism identified homozygous frameshift mutations before the first transmembrane domain in a subject born to first-cousins parents of Pakistani descent as well as compound-heterozygous mutations (a combination of a frameshift mutation and an intronic mutation that alters mRNA splicing) in an individual born to a non-consanguineous couple of African descent. Subsequently, targeted mutation analysis of TRPV6 performed on four other individuals (born to non-consanguineous Japanese parents) with similar X-rays findings identified compound-heterozygous mutations. The skeletal findings improved or resolved in most subjects during the first few months of life. We identified three missense variants (at the outer edges of the second and third transmembrane domains) that alter the localization of the TRPV6: one recurrent variant at the S2-S3 loop and two recurrent variants (in the fourth ankyrin repeat domain) that impair TRPV6 stability. Compound heterozygous loss-of-function mutations for the pathogenic frameshift allele and the allele with an intronic c.607+5G>A mutation resulted in the most severe phenotype. These results suggest that TNHP is an autosomal-recessive disease caused by TRPV6 mutations that affect maternal-fetal calcium transport.

Carbon fibre reinforced polymer (CFRP) composites structures are widely used in aeroplane structures. When a lightning strike affects fasteners or leak electric current of the lightning strike arrives at fasteners, the fasteners play serve as conducting electrodes for the CFRP plate. This current might cause complicated damage in the CFRP plate. The authors have developed self-sensing TDR to detect damage. Self-sensing TDR is used in this study to monitor lightning strike damage around a CFRP plate fastener hole. The lightning strike electric current is applied directly to a fastener. Thereafter, self-sensing TDR is applied. The lightning strike damage is investigated using cross-sectional inspection to clarify the mechanisms of the monitoring using TDR. Results show that the method can detect a 30 kA strike. Peeling of the GFRP insulator causes a characteristic impedance change, which in turn causes signal reflection of the transmission line.

The article Hypotonicity-induced cell swelling activates TRPA1, written by Fumitaka Fujita, Kunitoshi Uchida, Yasunori Takayama, Yoshiro Suzuki, Masayuki Takaishi and Makoto Tominaga, was originally published electronically on the publisher’s internet portal (currently SpringerLink) on 16 June 2017 without open access.

Brown adipose tissue (BAT), a major site for mammalian non-shivering thermogenesis, could be a target for prevention and treatment of human obesity. Transient receptor potential vanilloid 2 (TRPV2), a Ca(2+)-permeable non-selective cation channel, plays vital roles in the regulation of various cellular functions. Here, we show that TRPV2 is expressed in brown adipocytes and that mRNA levels of thermogenic genes are reduced in both cultured brown adipocytes and BAT from TRPV2 knockout (TRPV2KO) mice. The induction of thermogenic genes in response to β-adrenergic receptor stimulation is also decreased in TRPV2KO brown adipocytes and suppressed by reduced intracellular Ca(2+) concentrations in wild-type brown adipocytes. In addition, TRPV2KO mice have more white adipose tissue and larger brown adipocytes and show cold intolerance, and lower BAT temperature increases in response to β-adrenergic receptor stimulation. Furthermore, TRPV2KO mice have increased body weight and fat upon high-fat-diet treatment. Based on these findings, we conclude that TRPV2 has a role in BAT thermogenesis and could be a target for human obesity therapy.

In this paper, we applied a multiscale numerical scheme called the seamless-domain method (SDM) to nonlinear elliptic boundary value problems. Although the SDM is meshfree, it can obtain a high-resolution solution whose dependent-variable gradient(s) is sufficiently smooth and continuous. The SDM models with only coarse-grained points can produce accurate solutions for both linear heat conduction problems and linear elastic problems. This manuscript presents a simple nonlinear solver for the SDM analysis of heterogeneous materials. Although the solver can easily approximate the solutions to nonlinear multiscale problems, it does not require an iterative multiscale analysis at every convergence calculation. In other words, the proposed scheme does not completely interactively couple the multiple scales. We present numerical examples of nonlinear stationary heat conduction analyses of heterogeneous fields and compare the SDM model, the direct finite-element model, and the homogenized model based on the homogenization theory. For a real heterogeneous structure (graphite fiber composite) that did not have strong material nonlinearities, the SDM model using only 925 points gave a solution with similar precisions as an ordinary finite element solution using hundreds of thousands of nodes. To investigate the limitations of the method, we also applied the SDM to imaginary materials with various strengths of thermal property nonlinearities.

In this paper, we propose a specialized probe to detect in-plane and out-of-plane fiber waviness in unidirectional carbon fiber-reinforced plastics and to characterize fiber orientations by an eddy current-based nondestructive technique. Experimental studies show that the proposed probe can detect in-plane fiber waviness with amplitude of 1.1 mm and length of 15.9 mm in a thin unidirectional carbon fiber reinforced plastic at sufficiently high drive frequency. The validity of the proposed method is verified through three-dimensional finite element method analysis. Variation in amplitude and phase of output signal obtained in numerical analyses qualitatively agreed with experimental results. Out-of-plane fiber waviness induced in a thick unidirectional carbon fiber-reinforced plastic can also be detected using the proposed probe. It is found that output signals in complex plane obtained during scanning a material with out-of-plane waviness become ring-shaped plots. Those plots in complex plane are used to identify the presence and location of out-of-plane fiber waviness.

By using differential mRNA display to monitor the molecular alterations associated with adaptation of euryhaline eels to different salinities, we identified a cDNA fragment strongly induced in seawater eel gills. Cloning of a full-length cDNA and its expression in COS-7 cells indicated that the clone codes for an inward rectifier K+ channel (eKir) of 372 amino acid residues, which has two transmembrane segments and a typical pore-forming region (H5). Only low sequence similarities are present, except the H5 region, compared with other members of the inward rectifier K+ channel family (Kir). Consistent with this divergence in the amino acid sequence, a phylogenetic analysis indicated early divergence and independent evolution of eKir from other members; it is only distantly related to the Kir5.0 subfamily members. RNase protection analysis showed that eKir is highly expressed in the seawater eel gill, kidney, and posterior intestine but very weakly in freshwater eels. Immunohistochemistry of gill sections revealed dense localization of eKir in the chloride cells. Immunoelectron microscopy indicated that eKir is mainly present in the microtubular system in the chloride cell. This location and its salt-inducible nature suggest that the eKir channel cloned here is a novel member of the Kir5.0 subfamily of the Kir family and is implicated in osmoregulation.

Prostate cancer is a major health concern as it has the second highest incidence rate among cancers in men. Despite progress in tumor diagnostics and therapeutic approaches, prognosis for men with advanced disease remains poor. In this review we provide insight into the changes of the intermediary metabolism in normal prostate and prostate cancer. In contrast to normal cells, prostate cancer cells are reprogrammed for optimal energy-efficiency with a functional Krebs cycle and minimal apoptosis rates. A key element in this relationship is the uniquely high zinc level of normal prostate epithelial cells. Zinc is transported by the SLC30 and SLC39 families of zinc transporters. However, in prostate cancer the intracellular zinc content is remarkably reduced and expression levels of certain zinc transporters are altered. Here, we summarize the role of different zinc transporters in the development of prostate cancer.

Maternal-fetal calcium (Ca(2+)) transport is crucial for fetal Ca(2+) homeostasis and bone mineralization. In this study, the physiological significance of the transient receptor potential, vanilloid 6 (TRPV6) Ca(2+) channel in maternal-fetal Ca(2+) transport was investigated using Trpv6 knockout mice. The Ca(2+) concentration in fetal blood and amniotic fluid was significantly lower in Trpv6 knockout fetuses than in wildtypes. The transport activity of radioactive Ca(2+) ((45)Ca) from mother to fetuses was 40% lower in Trpv6 knockout fetuses than in wildtypes. The ash weight was also lower in Trpv6 knockout fetuses compared with wildtype fetuses. TRPV6 mRNA and protein were mainly localized in intraplacental yolk sac and the visceral layer of extraplacental yolk sac, which are thought to be the places for maternal-fetal Ca(2+) transport in mice. These expression sites were co-localized with calbindin D(9K) in the yolk sac. In wildtype mice, placental TRPV6 mRNA increased 14-fold during the last 4 days of gestation, which coincides with fetal bone mineralization. These results provide the first in vivo evidence that TRPV6 is involved in maternal-fetal Ca(2+) transport. We propose that TRPV6 functions as a Ca(2+) entry pathway, which is critical for fetal Ca(2+) homeostasis.

Ca2+ is essential for numerous physiological functions in our bodies. Therefore, its homeostasis is finely maintained through the coordination of intestinal absorption, renal reabsorption, and bone resorption. The Ca2+-selective epithelial channels TRPV5 and TRPV6 have been identified, and their physiological roles have been revealed: TRPV5 is important in final renal Ca2+ reabsorption, and TRPV6 has a key role in intestinal Ca2+ absorption. The TRPV5 knockout mice exhibit renal leak hypercalciuria and accordingly upregulate their intestinal TRPV6 expression to compensate for their negative Ca2+ balance. In contrast, despite their severe negative Ca2+ balance, TRPV6-null mice do not display any compensatory mechanism, thus resulting in secondary hyperparathyroidism. These results indicate that the genes for TRPV5 and TRPV6 are differentially regulated in human diseases associated with disturbed Ca2+ balance such as hypercalciuria, osteoporosis, and vitamin D–resistant rickets.

Transient receptor potential vanilloid 1 (TRPV1) is activated by elevated temperature (>42 °C), and it has been reported that cold temperature decreases capsaicin-induced TRPV1 activity. In contrast, transient receptor potential melastatin 8 (TRPM8) is activated by low temperatures and menthol, and heat stimulation suppresses menthol-evoked TRPM8 currents. These findings suggest that the effects of specific agents on TRPV1 and TRPM8 channels are intricately interrelated. We examined the effects of menthol on human (h)TRPV1 and of capsaicin on hTRPM8. hTRPV1 currents activated by heat and capsaicin were inhibited by menthol, whereas hTRPM8 currents activated by cold and menthol were similarly inhibited by capsaicin. An in vivo sensory irritation test showed that menthol conferred an analgesic effect on the sensory irritation evoked by a capsaicin analogue. These results indicate that in our study the agonists of TRPV1 and TRPM8 interacted with both of these channels and suggest that the anti-nociceptive effects of menthol can be partially explained by this phenomenon. Electronic supplementary material The online version of this article (doi:10.1007/s12576-015-0427-y) contains supplementary material, which is available to authorized users.

Claudins are major components of tight junctions and contribute to the epithelial-harrier function by restricting free diffusion of solutes through the paracellular pathway. We have mapped a new locus for recessive renal magnesium loss on chromosome 1p34.2 and have identified mutations in CLDN19, a member of the claudin multigene family, in patients affected by hypomagnesemia, renal failure, and severe ocular abnormalities. CLDN19 encodes the tight-junction protein claudin-19, and we demonstrate high expression of CLDN19 in renal tubules and the retina. The identified mutations interfere severely with either cell-membrane trafficking or the assembly of the claudin-19 protein. The identification of CLDN19 mutations in patients with chronic renal failure and severe visual impairment supports the fundamental role of claudln-19 for normal renal tubular function and undisturbed organization and development of the retina. © 2006 by The American Society of Human Genetics. All rights reserved., published_or_final_version