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Abstract We have reported that an environmental pollutant, cadmium, promotes cell death in the human renal tubular cells (RTCs) through hyperactivation of a serine/threonine kinase Akt. However, the molecular mechanisms downstream of Akt in this process have not been elucidated. Cadmium has a potential to accumulate misfolded proteins, and proteotoxicity is involved in cadmium toxicity. To clear the roles of Akt in cadmium exposure-induced RTCs death, we investigated the possibility that Akt could regulate proteotoxicity through autophagy in cadmium chloride (CdCl2)-exposed HK-2 human renal proximal tubular cells. CdCl2 exposure promoted the accumulation of misfolded or damaged proteins, the formation of aggresomes (pericentriolar cytoplasmic inclusions), and aggrephagy (selective autophagy to degrade aggresome). Pharmacological inhibition of Akt using MK2206 or Akti-1/2 enhanced aggrephagy by promoting dephosphorylation and nuclear translocation of transcription factor EB (TFEB)/transcription factor E3 (TFE3), lysosomal transcription factors. TFEB or TFE3 knockdown by siRNAs attenuated the protective effects of MK2206 against cadmium toxicity. These results suggested that aberrant activation of Akt attenuates aggrephagy via TFEB or TFE3 to facilitate CdCl2-induced cell death. Furthermore, these roles of Akt/TFEB/TFE3 were conserved in CdCl2-exposed primary human RTCs. The present study shows the molecular mechanisms underlying Akt activation that promotes cadmium-induced RTCs death.

Reports indicate that an interaction between TRPV4 and anoctamin 1 (ANO1) could be widely involved in water efflux of exocrine glands, suggesting that the interaction could play a role in perspiration. In secretory cells of sweat glands present in mouse foot pads, TRPV4 clearly colocalized with cytokeratin 8, ANO1, and aquaporin-5 (AQP5). Mouse sweat glands showed TRPV4-dependent cytosolic Ca2+ increases that were inhibited by menthol. Acetylcholine-stimulated sweating in foot pads was temperature-dependent in wild-type, but not in TRPV4-deficient mice and was inhibited by menthol both in wild-type and TRPM8KO mice. The basal sweating without acetylcholine stimulation was inhibited by an ANO1 inhibitor. Sweating could be important for maintaining friction forces in mouse foot pads, and this possibility is supported by the finding that wild-type mice climbed up a slippery slope more easily than TRPV4-deficient mice. Furthermore, TRPV4 expression was significantly higher in controls and normohidrotic skin from patients with acquired idiopathic generalized anhidrosis (AIGA) compared to anhidrotic skin from patients with AIGA. Collectively, TRPV4 is likely involved in temperature-dependent perspiration via interactions with ANO1, and TRPV4 itself or the TRPV4/ANO 1 complex would be targeted to develop agents that regulate perspiration.

Abstract There are a lot of temperature-sensitive proteins including transient receptor potential (TRP) channels. Some TRP channels are temperature receptors having specific activation temperatures in vitro that are within the physiological temperature range. Mice deficient in specific TRP channels show abnormal thermal behaviors, but the role of TRP channels in these behaviors is not fully understood. The Thermal Gradient Ring is a new apparatus that allows mice to freely move around the ring floor and not stay in a corner. The system can analyze various factors (e.g., ‘Spent time’, ‘Travel distance’, ‘Moving speed’, ‘Acceleration’) associated with temperature-dependent behaviors of TRP-deficient mice. For example, the Ring system clearly discriminated differences in temperature-dependent phenotypes between mice with diabetic peripheral neuropathy and TRPV1 −/− mice, and demonstrated the importance of TRPV3 in temperature detection in skin. Studies using the Thermal Gradient Ring system can increase understanding of the molecular basis of thermal behaviors in mice and in turn help develop strategies to affect responses to different temperature conditions in humans.

Abstract Demand-adjusted and cell type specific rates of protein synthesis represent an important safeguard for fate and function of long-term hematopoietic stem cells. Here, we identify increased protein synthesis rates in the fetal hematopoietic stem cell pool at the onset of hematopoietic failure in Fanconi Anemia, a prototypical DNA repair disorder that manifests with bone marrow failure. Mechanistically, the accumulation of misfolded proteins in Fancd2−/− fetal liver hematopoietic stem cells converges on endoplasmic reticulum stress, which in turn constrains midgestational expansion. Restoration of protein folding by the chemical chaperone tauroursodeoxycholic acid, a hydrophilic bile salt, prevents accumulation of unfolded proteins and rescues Fancd2−/− fetal liver long-term hematopoietic stem cell numbers. We find that proteostasis deregulation itself is driven by excess sterile inflammatory activity in hematopoietic and stromal cells within the fetal liver, and dampened Type I interferon signaling similarly restores fetal Fancd2−/− long-term hematopoietic stem cells to wild type-equivalent numbers. Our study reveals the origin and pathophysiological trigger that gives rise to Fanconi anemia hematopoietic stem cell pool deficits. More broadly, we show that fetal protein homeostasis serves as a physiological rheostat for hematopoietic stem cell fate and function.

Cell volume regulation (CVR) is a prerequisite for animal cells to survive and fulfill their functions. CVR dysfunction is essentially involved in the induction of cell death. In fact, sustained normotonic cell swelling and shrinkage are associated with necrosis and apoptosis, and thus called the necrotic volume increase (NVI) and the apoptotic volume decrease (AVD), respectively. Since a number of ubiquitously expressed ion channels are involved in the CVR processes, these volume-regulatory ion channels are also implicated in the NVI and AVD events. In Part 1 and Part 2 of this series of review articles, we described the roles of swelling-activated anion channels called VSOR or VRAC and acid-activated anion channels called ASOR or PAC in CVR and cell death processes. Here, Part 3 focuses on therein roles of Ca2+-permeable non-selective TRPM2 and TRPM7 cation channels activated by stress. First, we summarize their phenotypic properties and molecular structure. Second, we describe their roles in CVR. Since cell death induction is tightly coupled to dysfunction of CVR, third, we focus on their participation in the induction of or protection against cell death under oxidative, acidotoxic, excitotoxic, and ischemic conditions. In this regard, we pay attention to the sensitivity of TRPM2 and TRPM7 to a variety of stress as well as to their capability to physicall and functionally interact with other volume-related channels and membrane enzymes. Also, we summarize a large number of reports hitherto published in which TRPM2 and TRPM7 channels are shown to be involved in cell death associated with a variety of diseases or disorders, in some cases as double-edged swords. Lastly, we attempt to describe how TRPM2 and TRPM7 are organized in the ionic mechanisms leading to cell death induction and protection.

Summary: Neurons contribute to the regeneration of projected tissues; however, it remains unclear whether they are involved in the non-innervated tissue regeneration. Herein, we showed that a neuronal tachykinin-like receptor at 86C (TkR86C) is required for the repair of non-innervated wing discs in Drosophila. Using a genetic tissue repair system in Drosophila larvae, we performed genetic screening for G protein-coupled receptors to search for signal mediatory systems for remote tissue repair. An evolutionarily conserved neuroinflammatory receptor, TkR86C, was identified as the candidate receptor. Neuron-specific knockdown of TkR86C impaired disc repair without affecting normal development. We investigated the humoral metabolites of the kynurenine (Kyn) pathway regulated in the fat body because of their role as tissue repair-mediating factors. Neuronal knockdown of TkR86C hampered injury-dependent changes in the expression of vermillion in the fat body and humoral Kyn metabolites. Our data indicate the involvement of TkR86C neurons upstream of Kyn metabolism in non-autonomous tissue regeneration.

Abstract Background During metastasis, cancer cells undergo epithelial-mesenchymal transition (EMT) in response to transforming growth factor-β (TGF-β), which is abundant in the tumor microenvironment, and acquire invasive and metastatic potentials. Metastasis to distant organs requires intravascular invasion and extravasation of cancer cells, which is accompanied by the disruption of the adhesion between vascular endothelial cells. Cancer cell-derived extracellular vesicles (EVs) have been suggested to induce the destabilization of normal blood vessels at the metastatic sites. However, the roles of EVs secreted from cancer cells that have undergone EMT in the destabilization of blood vessels remain to be elucidated. In the present study, we characterized EVs secreted by oral cancer cells undergoing TGF-β-induced EMT and elucidated their effects on the characteristics of vascular endothelial cells. Methods Induction of EMT by TGF-β in human oral cancer cells was assessed using quantitative RT-PCR (qRT-PCR) and immunocytochemistry. Oral cancer cell-derived EVs were isolated from the conditioned media of oral cancer cells that were treated with or without TGF-β using ultracentrifugation, and characterized using nanoparticle tracking analysis and immunoblotting. The effects of EVs on human umbilical artery endothelial cells were examined by qRT-PCR, cellular staining, and permeability assay. The significant differences between means were determined using a t-test or one-way analysis of variance with Tukey’s multiple comparisons test. Results Oral cancer cells underwent EMT in response to TGF-β as revealed by changes in the expression of epithelial and mesenchymal cell markers at both the RNA and protein levels. Oral cancer cells treated with TGF-β showed increased EV production and altered EV composition when compared with untreated cells. The EVs that originated from cells that underwent EMT by TGF-β induced endothelial-mesenchymal transition, which was characterized by the decreased and increased expression of endothelial and mesenchymal cell markers, respectively. EVs derived from oral cancer cells also induced intercellular gap formation which led to the loss of endothelial cell barrier stability. Conclusions EVs released from oral cancer cells that underwent TGF-β-induced EMT target endothelial cells to induce vascular destabilization. Detailed characterization of oral cancer-derived EVs and factors responsible for EV-mediated vascular instability will lead to the development of agents targeting metastasis.

The mechanisms by which the innate immune system senses damage have been extensively explored in multicellular organisms. In Drosophila, various types of tissue damage, including epidermal injury, tumor formation, cell competition, and apoptosis deficiency, induce sterile activation of the Toll pathway, a process that requires the use of extracellular serine protease (SP) cascades. Upon infection, the SP Spätzle (Spz)-processing enzyme (SPE) cleaves and activates the Toll ligand Spz downstream of two paralogous SPs, Hayan and Persephone (Psh). However, upon tissue damage, it is not fully understood which SPs establish Spz activation cascades nor what damage-associated molecules can activate SPs. In this study, using newly generated uncleavable spz mutant flies, we revealed that Spz cleavage is required for the sterile activation of the Toll pathway, which is induced by apoptosis-deficient damage of wing epidermal cells in adult Drosophila. Proteomic analysis of hemolymph, followed by experiments with Drosophila Schneider 2 (S2) cells, revealed that among hemolymph SPs, both SPE and Melanization Protease 1 (MP1) have high capacities to cleave Spz. Additionally, in S2 cells, MP1 acts downstream of Hayan and Psh in a similar manner to SPE. Using genetic analysis, we found that the upstream SPs Hayan and Psh contributes to the sterile activation of the Toll pathway. While SPE/MP1 double mutants show more impairment of Toll activation upon infection than SPE single mutants, Toll activation is not eliminated in these apoptosis-deficient flies. This suggests that Hayan and Psh sense necrotic damage, inducing Spz cleavage by SPs other than SPE and MP1. Furthermore, hydrogen peroxide, a representative damage-associated molecule, activates the Psh-Spz cascade in S2 cells overexpressing Psh. Considering that reactive oxygen species (ROS) were detected in apoptosis-deficient wings, our findings highlight the importance of ROS as signaling molecules that induce the activation of SPs such as Psh in response to damage.

In this study, a method was developed for the management of marine plastic waste via the production of activated carbon. The specific surface area, micropore volume, and mesopore volume of marine-plastic-based activated carbon prepared at selected temperatures and using selected activator weight ratios were measured, and the specific capacitance and supercapacitor electrode performance were evaluated. At an activation temperature of 800 °C and a raw material to 8 M KOH weight ratio of 1:7, a specific capacitance of 201F/g and a high surface area of 2389 m2/g were obtained. Therefore, marine plastic waste-based activated carbon can be used as the electrode material in supercapacitors.

Abstract Objectives The periodontal ligament (PDL) is an important component of periodontium to support dental structure in the alveolar socket. Regeneration of PDL tissue is an effective treatment option for periodontal disease and the profiling of genes involved in this process will be informative. Therefore, our study aims to accurately delineate the profiling of gene expression for PDL tissue regeneration. Materials and Methods We isolated PDL tissues and PDL fibroblasts (PDLFs) from premolar teeth, which were extracted from healthy periodontal status patients undergoing orthodontic treatment. Messenger RNA (mRNA) expression in PDL tissue and PDLFs were analyzed using Cap analysis gene expression, which is a second‐generation sequencing technique to create profiling. We also determined the protein expression using Western blot. Results Collagens (type I, III, and VI), noncollagenous proteins (periostin and osteonectin), and proteoglycans (asporin, lumican, decorin, and osteomodulin) were highly expressed in PDL tissue. Integrin, β1 was also expressed in PDL tissue. On comparison of gene expression between PDL tissue and PDLFs, four PDL marker genes, osteopontin, asporin, periostin, and osteonectin, were decreased in PDLFs. The genes for gene regulation were also highly expressed. Conclusions Our study demonstrated the overall profiling of mRNA expression in PDL tissue and analyzed the important genes which may be useful for providing specific information for the reconstruction of PDL. We also identified the difference in gene expression between PDL tissue and PDLFs which might provide insights towards PDL regeneration.

The presence of cancer can induce systemic disruption of the host homeostasis. Here, the authors show that different solid tumours remotely increase hepatic nicotinamide-Nmethyltransferase disrupting the host urea cycle metabolism in the liver.

Fanconi Anemia (FA) is an inherited bone marrow (BM) failure disorder commonly diagnosed during school age. However, in murine models, disrupted function of FA genes leads to a much earlier decline in fetal liver hematopoietic stem cell (FL HSC) number that is associated with increased replication stress (RS). Recent reports have shown mitochondrial metabolism and clearance are essential for long-term BM HSC function. Intriguingly, impaired mitophagy has been reported in FA cells. We hypothesized that RS in FL HSC impacts mitochondrial metabolism to investigate fetal FA pathophysiology. Results show that experimentally induced RS in adult murine BM HSCs evoked a significant increase in mitochondrial metabolism and mitophagy. Reflecting the physiological RS during development in FA, increase mitochondria metabolism and mitophagy were observed in FANCD2-deficient FL HSCs, whereas BM HSCs from adult FANCD2-deficient mice exhibited a significant decrease in mitophagy. These data suggest that RS activates mitochondrial metabolism and mitophagy in HSC.

Abstract Tissue aging is a major cause of aging-related disabilities and a shortened life span. Understanding how tissue aging progresses and identifying the factors underlying tissue aging are crucial; however, the mechanism of tissue aging is not fully understood. Here we show that the biosynthesis of S-adenosyl-methionine (SAM), the major cellular donor of methyl group for methylation modifications, potently accelerates the aging-related defects during Drosophila oogenesis. An aging-related increase in the SAM-synthetase (Sam-S) levels in the germline leads to an increase in ovarian SAM levels. Sam-S-dependent biosynthesis of SAM controls aging-related defects in oogenesis through two mechanisms, decreasing the ability to maintain germline stem cells and accelerating the improper formation of egg chambers. Aging-related increases in SAM commonly occur in mouse reproductive tissue and the brain. Therefore, our results raise the possibility suggesting that SAM is the factor related to tissue aging beyond the species and tissues.

We herein report the first case of lupus-related protein-losing enteropathy associated with pseudo-pseudo Meigs’ syndrome. Lupus-related protein-losing enteropathy and pseudo-pseudo Meigs’ syndrome are extremely rare complications in patients with systemic lupus erythematosus, Both have a similar clinical course characterized by producing marked ascites, and respond to steroids in typical cases. However, in our case, steroid monotherapy was inadequate and the addition of hydroxychloroquine was effective for their treatment. Furthermore, no reports have previously confirmed elevated CA 125 levels with lupus-related protein-losing enteropathy or increased 99mTc-HSA activity with pseudo-pseudo Meigs’ syndrome. In addition, we are the first to report an evaluation of the histopathology of lupus-related protein-losing enteropathy. Previously reported cases have been described as being caused by either pseudo-Meigs’s syndrome or lupus-related protein-losing enteropathy as the cause of the rare pathology that causes marked pleural effusion and ascites in patients with systemic lupus erythematosus, but it has not been evaluated whether the other is co-occurring. Our case highlights that there is a potential case of overlapping lupus-related protein-losing enteropathy and pseudo-Pseudo-Meigs’s syndrome. Furthermore, it is possible that patients with marked ascites with elevated CA 125 levels were mistakenly diagnosed with Meigs’s syndrome or pseudo-Meigs’s syndrome associated with malignant or benign ovarian tumors and underwent surgery. Clinicians should not forget SLE with pseudo-Pseudo-Meigs’s syndrome as one of the differential diagnoses for marked ascites with elevated CA 125 levels.

Cholesteatoma is a benign tumor of the middle ear. Tympanoplasty is performed to remove cholesteatoma, prevent recurrence, and avoid complications. Previously, microscopy was used for tympanoplasty; however, endoscopy has become increasingly popular for this procedure. The effectiveness of endoscopy and the appropriate candidacy for endoscopic ear surgery remain controversial. In this retrospective chart review study, we enrolled 107 patients with cholesteatoma who underwent tympanoplasty and compared the microscopic approach (71 patients) and the endoscopic approach (36 patients) at different stages to clarify the benefits of using endoscopy and to determine candidacy for endoscopic ear surgery. Approach selection, complication rate, recurrence rate, and postoperative hearing threshold were compared between microscopic and endoscopic approaches in stages I, II, and III. Endoscopy was used more often than microscopy for early-stage (stage I) cholesteatoma (p = 0.005) and less frequently for advanced-stage (stage II) cholesteatoma (p = 0.02). Endoscopy surgery resulted in chorda tympani injury less often than microscopic surgery (p = 0.049); however, there were no significant differences between these two groups in terms of recurrence rate or postoperative hearing outcome. Endoscopy is particularly useful for early-stage cholesteatoma, and both approaches show no difference in hearing outcome in stage I and II; nevertheless, further research is required to determine an appropriate approach for more advanced stages (stage III). [ABSTRACT FROM AUTHOR]

The authors solve the crystal structure of OsGA3ox2 and predict that of OsGA3ox1. These enzymes catalyze the final step in the biosynthesis of gibberellin, one of the plant hormones. Evolutionary analysis combined with the new structure reveal important aspects of the OsGA3ox1’s function in plant male reproduction.

Objective Vestibular impairment has been observed in patients with congenital hearing loss, but little is known about the vestibular anatomy and function of those in this group with inner ear malformations. This study aims to investigate the association between vestibulocochlear anatomy and vestibular function test results in children with inner ear malformations. Study Design Case series with chart review. Setting Pediatric patients with inner ear malformations presenting with bilateral profound hearing loss at a tertiary hospital from 1999 to 2017. Methods Ears were classified into subgroups based on anatomic abnormalities seen on computed tomography imaging. Cervical vestibular evoked myogenic potential (cVEMP), rotatory chair, and caloric test results were obtained and collated. Descriptive and inferential statistics were calculated. Results Of 82 ears, 29.3% had incomplete partition type II malformation, the most common type. The second-most common type was isolated vestibular organ anomaly (20.7%), which is not included in currently accepted categories. Most ears exhibited abnormal vestibular function. Abnormal vestibule volume was associated with a nonreactive cVEMP ( P < .001). Radiologically abnormal lateral semicircular canals were associated with abnormal caloric and rotatory chair results ( P < .001). Conclusion With a relatively large number of cases of isolated vestibular organ anomaly not only in our study but also in previous publications, we suggest that this category be added to the subsets of inner ear malformations. Abnormal vestibule volume was significantly associated with a nonreactive cVEMP finding. The majority of patients with hearing loss secondary to inner ear malformations have abnormal vestibular function test results.