A simple and rapid assay of lysosomal-targeting CDy6 for long-term real-time viability assessments in 2D and 3D in vitro culture models

CDy6, a BODIPY-derived compound, is used to label lysosomes and visualize proliferating cells. However, its effectiveness in long-term, real-time cell viability assays using 2D or 3D cell culture models is unclear. We evaluated the suitability of CDy6 by assessing cell health using human keratinocyte and fibroblast cell lines in both models. Cells were stained with CDy6 or other dyes and fluorescent images were obtained with confocal microscopy. CLV extracts derived from CDy6-stained HaCaT cells were also dissolved with DMSO and analyzed using a spectrometer. Furthermore, we added CDy6-stained collagen hydrogels to CCD-986sk cells, loaded them into a frame construction to establish a 3D dermal layer for long-term culture, and analyzed the status of the CLVs. The CLV method, also measured using a spectrometer, yielded results similar to MTT assay for validating viability. In contrast to calcein AM staining, the CLV method allows for both absorbance measurement and imaging under short-term and long-term culture conditions with less cytotoxicity. In conclusion, the CLV method provides a simple and sensitive tool for assessing the status of live cells in 2D and 3D in vitro cell culture models and can be used as an alternative to animal testing, such as with 3D artificial skin models.

UBAP2 plays a role in bone homeostasis through the regulation of osteoblastogenesis and osteoclastogenesis

Osteoporosis is a condition characterized by decreased bone mineral density (BMD) and reduced bone strength, leading to an increased risk of fractures. Here, to identify novel risk variants for susceptibility to osteoporosis-related traits, an exome-wide association study is performed with 6,485 exonic single nucleotide polymorphisms (SNPs) in 2,666 women of two Korean study cohorts. The rs2781 SNP in UBAP2 gene is suggestively associated with osteoporosis and BMD with p-values of 6.1 × 10-7 (odds ratio = 1.72) and 1.1 × 10-7 in the case-control and quantitative analyzes, respectively. Knockdown of Ubap2 in mouse cells decreases osteoblastogenesis and increases osteoclastogenesis, and knockdown of ubap2 in zebrafish reveals abnormal bone formation. Ubap2 expression is associated with E-cadherin (Cdh1) and Fra1 (Fosl1) expression in the osteclastogenesis-induced monocytes. UBAP2 mRNA levels are significantly reduced in bone marrow, but increased in peripheral blood, from women with osteoporosis compared to controls. UBAP2 protein level is correlated with the blood plasma level of the representative osteoporosis biomarker osteocalcin. These results suggest that UBAP2 has a critical role in bone homeostasis through the regulation of bone remodeling.

FIR-preconditioning promotes Akt-mTOR-exosome manufacture in cooperation with MITF to boost resilience of rat bone marrow-derived stem cells

A previous study from our laboratory observed the protective effects of far-infrared irradiation (FIR) on bone marrow-derived stem cells (BMSCs) against oxidative stress. However, it remains unknown precisely how FIR influences BMSC survival. We identify an unexpected route among the expression of MITF, BCL2, mTOR, and exosome in FIR-preconditioned BMSCs. MITF siRNA demonstrated that loss of MITF expression not only inhibited cell proliferation but also reduced the FIR-mediated expression of mTOR, BCL2, and exosome. mTOR signaling pathways have been implicated in cell growth, proliferation, and survival. We also found that rapamycin, a potent and selective inhibitor of mTOR, when combined with MITF siRNA, repressed FIR-mediated CD63 and BCL2 expression. In addition, FIR-preconditioned BMSCs demonstrated more tolerance in multiple stressful environments than untreated BMSCs. The elevated exosomes in conditioned medium derived from FIR-preconditioned BMSCs also repaired H9c2 cells that sustained cellular damage after subjected to an array of environmental stress conditions. Taken together, these results reveal a possible mechanism about how FIR-preconditioned BMSCs and its conditioned media could contribute to cellular resilience during environmental changes via MITF-Akt-mTOR associated with exosome manufacture. FIR preconditioning could thus complement and improve therapeutic applications of BMSCs on outcomes of various disorders.

Transwell-Hypoxia Method Facilitates the Outgrowth of 3D-Printed Collagen Scaffolds Loaded with Cryopreserved Patient-Derived Melanoma Explants

A previous study from our laboratory demonstrated the effects of in vitro three-dimensional (3D)-printed collagen scaffolds on the maintenance of cryopreserved patient-derived melanoma explants (PDMEs). However, it remains unknown whether 3D-printed collagen scaffolds (3D-PCSs) can be harmonized with any external culture conditions to increase the growth of cryopreserved PDMEs. In this study, 3D-PCSs were manufactured with a 3DX bioprinter. The 3D-printed collagen scaffold-on-frame construction was loaded with fragments of cryopreserved PDMEs (approximately 1-2 mm). 3D-PCSs loaded with patient-derived melanoma explants (3D-PCS-PDMEs) were incubated using two types of methods: (1) in transwells in the presence of a low concentration of oxygen (transwell-hypoxia method) and (2) using a traditional adherent attached to the bottom flat surface of a standard culture dish (traditional flat condition). In addition, we used six different types of media (DMEM high glucose, MEM α, DMEM/F12, RPMI1640, fibroblast basal medium (FBM), and SBM (stem cell basal medium)) for 7 days. The results reveal that the culture conditions of MEM α, DMEM/F12, and FBM using the transwell-hypoxia method show greater synergic effects on the outgrowth of the 3D-PCS-PDME compared to the traditional flat condition. In addition, the transwell-hypoxia method shows a higher expression of the MMP14 gene and the multidrug-resistant gene product 1 (MDR1) than in the typical culture method. Taken together, our findings suggest that the transwell-hypoxia method could serve as an improved, 3D alternative to animal-free testing that better mimics the skin's microenvironment using in vitro PDMEs.

Production of Multiple Cell-Laden Microtissue Spheroids with a Biomimetic Hepatic-Lobule-Like Structure

The construction of an in vitro 3D cellular model to mimic the human liver is highly desired for drug discovery and clinical applications, such as patient-specific treatment and cell-based therapy in regenerative medicine. However, current bioprinting strategies are limited in their ability to generate multiple cell-laden microtissues with biomimetic structures. This study presents a method for producing hepatic-lobule-like microtissue spheroids using a bioprinting system incorporating a precursor cartridge and microfluidic emulsification system. The multiple cell-laden microtissue spheroids can be successfully generated at a speed of approximately 45 spheroids min-1 and with a uniform diameter. Hepatic and endothelial cells are patterned in a microtissue spheroid with the biomimetic structure of a liver lobule. The spheroids allow long-term culture with high cell viability, and the structural integrity is maintained longer than that of non-structured spheroids. Furthermore, structured spheroids show high MRP2, albumin, and CD31 expression levels. In addition, the in vivo study reveals that structured microtissue spheroids are stably engrafted. These results demonstrate that the method provides a valuable 3D structured microtissue spheroid model with lobule-like constructs and liver functions.

Genetic Approaches Using Zebrafish to Study the Microbiota-Gut-Brain Axis in Neurological Disorders

The microbiota-gut-brain axis (MGBA) is a bidirectional signaling pathway mediating the interaction of the microbiota, the intestine, and the central nervous system. While the MGBA plays a pivotal role in normal development and physiology of the nervous and gastrointestinal system of the host, its dysfunction has been strongly implicated in neurological disorders, where intestinal dysbiosis and derived metabolites cause barrier permeability defects and elicit local inflammation of the gastrointestinal tract, concomitant with increased pro-inflammatory cytokines, mobilization and infiltration of immune cells into the brain, and the dysregulated activation of the vagus nerve, culminating in neuroinflammation and neuronal dysfunction of the brain and behavioral abnormalities. In this topical review, we summarize recent findings in human and animal models regarding the roles of the MGBA in physiological and neuropathological conditions, and discuss the molecular, genetic, and neurobehavioral characteristics of zebrafish as an animal model to study the MGBA. The exploitation of zebrafish as an amenable genetic model combined with in vivo imaging capabilities and gnotobiotic approaches at the whole organism level may reveal novel mechanistic insights into microbiota-gut-brain interactions, especially in the context of neurological disorders such as autism spectrum disorder and Alzheimer's disease.

Substance P enhances the local activation of NK1R-expressing c-kit+ cardiac progenitor cells in right atrium of ischemia/reperfusion-injured heart

BACKGROUND

Localization of neurokinin 1 receptor (NK₁R), the endogenous receptor for neuropeptide substance P (SP), has already been described for the right atrium (RA) of the heart. However, the biological role of SP/NK₁R signal pathways in the RA remains unclear. Sprague-Dawley rats were randomly divided into 4 groups (n = 22 each); subjected to sham, ischemia/reperfusion-injury (I/R), I/R with 5 nmole/kg SP injection (SP + I/R), and SP + I/R with 1 mg/kg RP67580 injection (RP, a selective non-peptide tachykinin NK₁R antagonist) (RP/SP + I/R). The left anterior descending coronary artery was occluded for 40 min followed by 1 day reperfusion with SP or SP + RP or without either. After 1 day, both atria and ventricles as well as the heart apexes were collected.

RESULTS

SP promoted the expression of c-Kit, GATA4, Oct4, Nanog, and Sox2 in only the RA of the SP + I/R rats via NK₁R activation. In agreement with these observations, NK₁R-expressing c-Kit⁺ Nkx2.5⁺GATA4⁺ cardiac progenitor cells (CPCs) in the ex vivo RA explant outgrowth assay markedly migrated out from RA^{1 day SP + I/R} approximately 2-fold increase more than RA^{1 day I/R}. Treatment of SP promoted proliferation, migration, cardiosphere formation, and potential to differentiate into cardiomyocytes. Using RP inhibitor, NK₁R antagonist not only inhibited cell proliferation and migration but also reduced the formation of cardiosphere and differentiation of c-Kit⁺ CPCs.

CONCLUSION

SP/NK₁R might play a role as a key mediator involved in the cellular response to c-Kit⁺ CPC expansion in RA of the heart within 24 h after I/R.

Diagnostic Performance of Multidetector Computerized Tomography in the Detection of Abdominal Complications Early and Late After Liver Transplantation: A 10-Year Experience

BACKGROUND

Multidetector computerized tomography (MDCT) is considered to be a fast noninvasive diagnostic technique for the evaluation of postoperative complications in patients with liver transplantation (LT). However, its role has not been fully established in the diagnosis for detecting complications after liver transplantation. The aim of this work was to evaluate the diagnostic performance of MDCT for detecting abdominal complications in the early and late periods after LT.

METHODS

We retrospectively enrolled 75 patients who had undergone LT from March 2006 to January 2010, followed by MDCT from March 2006 to November 2017. Patients were divided into 2 groups according to the timing after LT: within the first 3 months (early period) or ≥3 months after LT (late period). We evaluated vascular, biliary, and other complications on MDCT. Angiography, endoscopic retrograde cholangiography, and percutaneous transhepatic cholangiography were used as reference standards.

RESULTS

We initially found 77 complications in 45 patients (60.0%) with the use of MDCT. After comparison with the reference standards, 83 complications were diagnosed in 49 patients (65.3%). Forty-seven complications (34 vascular, 10 biliary, 3 other complications) were diagnosed in 33 patients (44.0%) during the early period, and 36 complications (6 vascular, 20 biliary, 10 other complications) were detected in 27 patients (36.0%) in the late period. The sensitivity, specificity, and diagnostic accuracy of MDCT for diagnosing overall complications were, respectively, 93.6%, 90.2%, and 92.0% in the early period (for vascular complications: 97.1%, 92.6%, and 94.3%,; for biliary complications: 80.0%, 100%, and 97.7%) and 77.8%, 98.1%, and 89.8% in the late period (for vascular complications: 83.3%, 100%, and 98.9%; for biliary complications: 65.0%, 98.6%, and 90.9%).

CONCLUSIONS

Although MDCT in the late period should be interpreted with caution in patients with suspected biliary complication, MDCT is a reliable diagnostic technique for the identification of early and late abdominal complications after LT.

Preconditioning with far-infrared irradiation enhances proliferation, cell survival, and migration of rat bone marrow-derived stem cells via CXCR4-ERK pathways

Far-infrared radiation (FIR) has been shown to exert positive effects on the cardiovascular system. However, the biological effects of FIR on bone marrow-derived stem cells (BMSCs) are not understood. In the present study, BMSCs were isolated from rat femur bone marrow and cultured in vitro. To investigate the effects of an FIR generator with an energy flux of 0.13 mW/cm² on rat BMSCs, survival of BMSCs was measured by crystal violet staining, and cell proliferation was additionally measured using Ez-Cytox cell viability, EdU, and Brd U assays. FIR preconditioning was found to significantly increase BMSC proliferation and survival against H₂O₂. The scratch and transwell migration assays showed that FIR preconditioning resulted in an increase in BMSC migration. qRT-PCR and Western blot analyses demonstrated that FIR upregulated Nanog, Sox2, c-Kit, Nkx2.5, and CXCR4 at both the mRNA and protein levels. Consistent with these observations, PD98059 (an ERK inhibitor) and AMD3100 (a CXCR4 inhibitor) prevented the activation of CXCR4/ERK and blocked the cell proliferation and migration induced by FIR. Overall, these findings provide the first evidence that FIR confers a real and significant benefit on the preconditioning of BMSCs, and might lead to novel strategies for improving BMSC therapy for cardiac ischemia.

Ottogi Inhibits Wnt/β-catenin Signaling by Regulating Cell Membrane Trafficking of Frizzled8

Wnt signaling controls critical developmental processes including tissue/body patterning. Here we report the identification of a novel regulator of Wnt signaling, OTTOGI (OTG), isolated from a large-scale expression screening of human cDNAs in zebrafish embryos. Overexpression of OTG in zebrafish embryos caused dorso-anteriorized phenotype, inhibited the expression of Wnt target genes, and prevented nuclear accumulation of β-catenin. Conversely, knockdown of zebrafish otg using specific antisense morpholino promoted nuclear accumulation of β-catenin and caused ventralization. However, OTG failed to rescue headless-like phenotype induced by inhibition of GSK-3β activity, suggesting that OTG acts upstream of GSK-3β. OTG bound specifically to Frizzled8 (Fz8) receptor and caused retention of Fz8 in the endoplasmic reticulum possibly by preventing N-linked glycosylation of Fz8. Taken together, our data indicate that OTG functions as a novel negative regulator of Wnt signaling during development by the modulation of cell surface expression of Fz receptor.

Zebrafish knockout of Down syndrome gene, DYRK1A, shows social impairments relevant to autism

BACKGROUND

DYRK1A maps to the Down syndrome critical region at 21q22. Mutations in this kinase-encoding gene have been reported to cause microcephaly associated with either intellectual disability or autism in humans. Intellectual disability accompanied by microcephaly was recapitulated in a murine model by overexpressing Dyrk1a which mimicked Down syndrome phenotypes. However, given embryonic lethality in homozygous knockout (KO) mice, no murine model studies could present sufficient evidence to link Dyrk1a dysfunction with autism. To understand the molecular mechanisms underlying microcephaly and autism spectrum disorders (ASD), we established an in vivo dyrk1aa KO model using zebrafish.

METHODS

We identified a patient with a mutation in the DYRK1A gene using microarray analysis. Circumventing the barrier of murine model studies, we generated a dyrk1aa KO zebrafish using transcription activator-like effector nuclease (TALEN)-mediated genome editing. For social behavioral tests, we have established a social interaction test, shoaling assay, and group behavior assay. For molecular analysis, we examined the neuronal activity in specific brain regions of dyrk1aa KO zebrafish through in situ hybridization with various probes including c-fos and crh which are the molecular markers for stress response.

RESULTS

Microarray detected an intragenic microdeletion of DYRK1A in an individual with microcephaly and autism. From behavioral tests of social interaction and group behavior, dyrk1aa KO zebrafish exhibited social impairments that reproduce human phenotypes of autism in a vertebrate animal model. Social impairment in dyrk1aa KO zebrafish was further confirmed by molecular analysis of c-fos and crh expression. Transcriptional expression of c-fos and crh was lower than that of wild type fish in specific hypothalamic regions, suggesting that KO fish brains are less activated by social context.

CONCLUSIONS

In this study, we established a zebrafish model to validate a candidate gene for autism in a vertebrate animal. These results illustrate the functional deficiency of DYRK1A as an underlying disease mechanism for autism. We also propose simple social behavioral assays as a tool for the broader study of autism candidate genes.

Cardioprotective effects of PKG activation by soluble GC activator, BAY 60-2770, in ischemia-reperfusion-injured rat hearts

Soluble guanylate cyclase (sGC) has been suggested as a therapeutic target for cardiac ischemia-reperfusion (IR) injury. Until now, the molecular mechanism of BAY 60-2770, a sGC activator, in cardiac IR injury has not been assessed. To identify the cardioprotective effects of BAY 60-2770 in IR-injured rat hearts, IR injury was established by occlusion of LAD for 40 min and reperfusion for 7 days, and the effects of BAY 60-2770 on myocardial protection were assessed by echocardiography and TTC staining. 5 nM and 5 μM of BAY 60-2770 were perfused into isolated rat hearts in a Langendorff system. After 10- or 30-min reperfusion with BAY 60-2770, cGMP and cAMP concentrations and PKG activation status were examined. Hearts were also perfused with 1 μM KT5823 or 100 μM 5-HD in conjunction with 5 nM Bay 60-2770 to evaluate the protective role of PKG. Mitochondrial oxidative stress was investigated under hypoxia-reoxygenation in H9c2 cells. In IR-injured rat hearts, BAY 60-2770 oral administration reduced infarct size by TTC staining and improved left ventricular function by echocardiography. Tissue samples from BAY 60-2770-perfused hearts had approximately two-fold higher cGMP levels. BAY 60-2770 increased PKG activity in the myocardium, and the reduced infarct area by BAY 60-2770 was abrogated by KT-5823 in isolated myocardium. In H9c2 cardiac myoblasts, hypoxia-reoxygenation-mediated mitochondrial ROS generation was diminished with BAY 60-2770 treatment, but was recovered by pretreatment with KT-5823. BAY 60-2770 demonstrated a protective effect against cardiac IR injury via mitoKATP opening and decreased mitoROS by PKG activation. BAY 60-2770 has a protective effect against cardiac IR injury via mitoKATP opening and decreased mitoROS by PKG activation. These results demonstrated that BAY 60-2770 may be used as a therapeutic agent for cardiac IR injury.

Prognostic significance of cachexia score assessed by CT in male patients with small cell lung cancer

To determine the prognostic significance of CT-determined cachexia scores (CSs) in 127 consecutive male small cell lung cancer (SCLC) patients, cross-sectional areas of muscle and fat tissues at the third lumbar vertebra (L3) were retrospectively measured on baseline CT images. CSs were determined based on the presence of sarcopenia and/or adipopenia. According to the presence of sarcopenia (L3 muscle index <55 cm² /m² , 86.8%) and adipopenia (L3 fat index <22 cm² /m² , 11.8%), CSs were defined as follows: CS2 (sarcopenia and adipopenia, 11.8%), CS1 (sarcopenia only, 74.8%) and CS0 (13.4%). CS2 was significantly related to lower body mass index (p < .001) and poor performance status (p = .002), and patients with CS2 had shorter OS than patients with CS1 or CS0 (median OS, 5.0 months vs. 8.9 months vs. 18.3 months; p = .007). Multivariable analysis revealed that CS was an independent prognostic factor of poor survival (HR, 1.99 for CS1 and 2.59 for CS2, p = .036 and .023, CS0 as a reference), along with extensive stage (p < .001), supportive care only (p < .001) and an elevated lactate dehydrogenase (p = .005). CT-determined CSs, based on the presence of sarcopenia and/or adipopenia, could be used to predict prognosis in male SCLC.

Mind Bomb-Binding Partner RanBP9 Plays a Contributory Role in Retinal Development

Ran-binding protein family member, RanBP9 has been reported in various basic cellular mechanisms and neuropathological conditions including schizophrenia. Previous studies have reported that RanBP9 is highly expressed in the mammalian brain and retina; however, the role of RanBP9 in retinal development is largely unknown. Here, we present the novel and regulatory roles of RanBP9 in retinal development of a vertebrate animal model, zebrafish. Zebrafish embryos exhibited abundant expression of ranbp9 in developing brain tissues as well as in the developing retina. Yeast two-hybrid screening demonstrated the interaction of RanBP9 with Mind bomb, a component of Notch signaling involved in both neurogenesis and neural disease autism. The interaction is further substantiated by co-localization studies in cultured cells. Knockdown of ranbp9 resulted in retinal dysplasia with defective proliferation of retinal cells, downregulation of neuronal differentiation marker huC, elevation of neural proliferation marker her4, and alteration of cell cycle marker p57kip2. Expression of the Müller glial cell marker glutamine synthase was also affected in knockdown morphants. Our results suggest that Mind bomb-binding partner RanBP9 plays a role during retinal cell development of zebrafish embryogenesis.

Enhanced-autophagy by exenatide mitigates doxorubicin-induced cardiotoxicity

OBJECTIVES

Exenatide is a glucagon-like peptide-1 analogue that mitigates myocardial injury caused by ischemia-reperfusion injury via the survival signaling pathway. We hypothesized that exenatide would provide a protective effect in doxorubicin-induced cardiotoxicity.

METHODS

H9c2 cardiomyocytes were pre-treated with exenatide followed by doxorubicin (DOX), and cell viability and intracellular reactive oxygen species (ROS) were subsequently measured. In order to determine the role of autophagy, we performed western blot as well as TUNEL and autophagosome staining. Additionally, rats were treated with exenatide 1h prior to every DOX treatment. Left ventricular (LV) function and performance were then assessed by echocardiography. Myocardial and serum ROS was measured with DHE fluorescence and ROS/RNS assay.

RESULTS

DOX-induced caspase-3 activation decreased after pre-treatment with exenatide both in vivo and in vitro. Oxidative stress was attenuated by exenatide in H9c2 cells, as well as in cardiac tissue and serum. The number of autophagosomes and autophagic markers were further increased by exenatide in the DOX-treated H9c2 cells, which mediated AMPK activation. Suppression of the autophagosome abolished exenatide-induced anti-apoptotic effect. Echocardiography showed that pre-treatment with exenatide significantly improved LV dysfunction that is induced by DOX treatment. Exenatide inhibits the DOX-induced production of intracellular ROS and apoptosis in the myocardium. The autophagic markers increased in exenatide pre-treated cardiac tissue.

CONCLUSION

Exenatide reduces DOX-induced apoptosis of cardiomyocytes by upregulating autophagy and improving cardiac dysfunction. These novel results highlight the therapeutic potential of exenatide to prevent doxorubicin cardiotoxicity.

Hair-growth-promoting effect of conditioned medium of high integrin α6 and low CD 71 (α6bri/CD71dim) positive keratinocyte cells

Keratinocyte stem/progenitor cells (KSCs) reside in the bulge region of the hair follicles and may be involved in hair growth. Hair follicle dermal papilla cells (HFDPCs) and outer root sheath (ORS) cells were treated with conditioned medium (CM) of KSCs. Moreover, the effects of KSC-CM on hair growth were examined ex vivo and in vivo. A human growth factor chip array and RT-PCR were employed to identify enriched proteins in KSC-CM as compared with CM from keratinocytes. KSC-CM significantly increased the proliferation of HFDPCs and ORS cells, and increased the S-phase of the cell cycle in HFDPCs. KSC-CM led to the phosphorylation of ATK and ERK1/2 in both cell types. After subcutaneous injection of KSC-CM in C3H/HeN mice, a significant increase in hair growth and increased proliferation of hair matrix keratinocytes ex vivo was observed. We identified six proteins enriched in KSC-CM (amphiregulin, insulin-like growth factor binding protein-2, insulin-like growth factor binding protein-5, granulocyte macrophage-colony stimulating factor, Platelet-derived growth factor-AA, and vascular endothelial growth factor). A growth-factor cocktail that contains these six recombinant growth factors significantly increased the proliferation of HFDPCs and ORS cells and enhanced the hair growth of mouse models. These results collectively indicate that KSC-CM has the potential to increase hair growth via the proliferative capacity of HFDPCs and ORS cells.

Mutations in DDX58, which encodes RIG-I, cause atypical Singleton-Merten syndrome

Singleton-Merten syndrome (SMS) is an autosomal-dominant multi-system disorder characterized by dental dysplasia, aortic calcification, skeletal abnormalities, glaucoma, psoriasis, and other conditions. Despite an apparent autosomal-dominant pattern of inheritance, the genetic background of SMS and information about its phenotypic heterogeneity remain unknown. Recently, we found a family affected by glaucoma, aortic calcification, and skeletal abnormalities. Unlike subjects with classic SMS, affected individuals showed normal dentition, suggesting atypical SMS. To identify genetic causes of the disease, we performed exome sequencing in this family and identified a variant (c.1118A>C [p.Glu373Ala]) of DDX58, whose protein product is also known as RIG-I. Further analysis of DDX58 in 100 individuals with congenital glaucoma identified another variant (c.803G>T [p.Cys268Phe]) in a family who harbored neither dental anomalies nor aortic calcification but who suffered from glaucoma and skeletal abnormalities. Cys268 and Glu373 residues of DDX58 belong to ATP-binding motifs I and II, respectively, and these residues are predicted to be located closer to the ADP and RNA molecules than other nonpathogenic missense variants by protein structure analysis. Functional assays revealed that DDX58 alterations confer constitutive activation and thus lead to increased interferon (IFN) activity and IFN-stimulated gene expression. In addition, when we transduced primary human trabecular meshwork cells with c.803G>T (p.Cys268Phe) and c.1118A>C (p.Glu373Ala) mutants, cytopathic effects and a significant decrease in cell number were observed. Taken together, our results demonstrate that DDX58 mutations cause atypical SMS manifesting with variable expression of glaucoma, aortic calcification, and skeletal abnormalities without dental anomalies.

The development of a nucleus staining fluorescent probe for dynamic mitosis imaging in live cells

The rapid and efficient synthesis of a novel fluorescent xanthone library (AX) and its application for the development of a new nucleus staining fluorescent probe (CDb12) for monitoring real-time mitosis progression in live cells is presented.

Induction of clusterin expression by neuronal cell death in Zebrafish

Clusterin, a protein associated with multiple functions, is expressed in a wide variety of mammalian tissues. Although clusterin is known to be involved in neurodegenerative diseases, ageing, and tumorigenesis, a detailed analysis of the consequences of gain- or loss-of-function approaches has yet to be performed to understand the underlying mechanisms of clusterin functions. Since clusterin levels change in neurological diseases, it is likely that clusterin contributes to cell death and degeneration in general. Zebrafish was investigated as a model system to study human diseases. During development, zebrafish clusterin was expressed in the notochord and nervous system. Embryonic overexpression of clusterin by mRNA microinjection did not affect axis formation, whereas its knock-down by anti-sense morpholino treatment resulted in neuronal cell death. To analyze the function of clusterin in neurodegeneration, a transgenic zebrafish was investigated, in which nitroreductase expression is regulated under the control of a neuron-specific huC promoter which is active between the stages of early neuronal precursors and mature neurons. Nitroreductase turns metronidazole into a cytotoxic agent that induces cell death within 12 h. After metronidazole treatment, transgenic zebrafish showed neuron-specific cell death. Interestingly, we also observed a dramatic induction of clusterin expression in the brain and spinal cord in these fish, suggesting a direct or indirect role of clusterin in neuronal cell death and thus, more generally, in neurodegeneration.

Physical characterization and in vitro skin permeation of solid lipid nanoparticles for transdermal delivery of quercetin

OBJECTIVE

Quercetin, a phenolic compound isolated from plants, can act as an antioxidant to protect the skin from oxidative stress induced by ultraviolet rays. The aims of this work were (i) to compare the physical characterization of quercetin-loaded solid lipid nanoparticles (QSLNs) and (ii) to investigate the enhanced skin permeation of quercetin using QSLNs.

METHODS

QSLNs were prepared with a certain amount lipid (palmitic acid) and the different ratio of surfactant (Tween(®) 80) by homogenization and ultrasonification method.

RESULTS

QSLNs showed mono-dispersed particle size distribution in the ranges of 274.0-986.6 nm and zeta potential from -50.4 to -29.4 mV. Entrapment efficiency of QSLN was 15.2-46.2%, and their crystallinity index was low (0-18.2%). In vitro occlusion test showed QSLN-2 has the highest occlusive effect due to its smallest particle size (274.0 nm), and through these result, QSLN-2 was selected as the optimum formulation. Transmission electron microscopy (TEM) analysis further confirmed the uniform spherical shape of QSLN-2 particles. Field emission-scanning electron microscope (FE-SEM) analysis and histological observation of hairless rat skin showed that the lipid particles of QSLN-2 formed a fused lipid film and, subsequently, it hydrated the surface of the rat skin. Franz diffusion cell was used to measure in vitro skin permeation of quercetin dissolved in propylene glycol (QPG), QSLN-2 and QSLN-3. The results showed that QSLN-2 (33.5 μg cm(-2) , 21.9%) exhibited higher skin permeability than QPG (6.6 μg cm(-2) , 4.2%) and QSLN-3 (14.2 μg cm(-2) , 9.1%), which was visually confirmed by confocal laser scanning microscope (CLSM) image analysis as well.

CONCLUSION

The results suggest that QSLN-2, prepared with a surfactant content of 2%, could be used as useful skin delivery system for transdermal delivery of hydrophobic antioxidants such as quercetin.

Leucine-rich glioma inactivated 3 is a melanogenic cytokine in human skin

Recently, we demonstrated that leucine-rich glioma inactivated 3 (LGI3) is expressed in human skin. However, the effects of LGI3 on melanocytes remain unknown. The present study demonstrated that LGI3 can serve to stimulate melanogenesis without affecting cell viability. To determine the effects of LGI3 on melanin synthesis, normal human melanocytes and Mel-Ab cells were treated with recombinant LGI3 and melanin content was measured. Our results showed that LGI3 promoted melanin synthesis in both cell types. Moreover, upregulation of microphthalmia-associated transcription factor (MITF) and tyrosinase was observed at both the mRNA and protein levels via RT-PCR and Western blotting, respectively. Furthermore, immunohistochemical staining showed that the expression of LGI3 increased in the basal layer of melasma skin samples, whereas it decreased slightly in vitiligo samples. These results suggest that LGI3 may play a role as a melanogenic cytokine in human skin.

Leucine-rich glioma inactivated 3 promotes HaCaT keratinocyte migration

Our finding that human skin expresses leucine-rich glioma inactivated 3 (LGI3) raises the question of the function of this cytokine in keratinocytes. We have shown that LGI3 stimulates human HaCaT keratinocyte migration without affecting viability or proliferation. Western blot analysis showed that LGI3 induced focal adhesion kinase activation, Akt phosphorylation, and glycogen synthase kinase 3β (GSK3β) phosphorylation in these cells. Using the scratch wound assay and a modified Boyden chamber, we found that LY294002, a selective phosphatidylinositol 3-kinase inhibitor, and LiCl, a selective GSK3β inhibitor, abolished LGI3-induced cell migration. We tested β-catenin levels after LGI3 treatment because the Akt-GSK3β pathway regulates β-catenin accumulation, and β-catenin promotes cell migration. LGI3 treatment increased β-catenin protein and nuclear localization, whereas LY294002 prevented LGI3-induced focal adhesion kinase and Akt activation as well as β-catenin accumulation. Overall, these data suggest that LGI3 stimulates HaCaT cell migration following β-catenin accumulation through the Akt pathway.

Ultraviolet B preconditioning enhances the hair growth-promoting effects of adipose-derived stem cells via generation of reactive oxygen species

Hypoxia induces the survival and regenerative potential of adipose-derived stem cells (ASCs), but there are tremendous needs to find alternative methods for ASC preconditioning. Therefore, this work investigated: (1) the ability of low-dose ultraviolet B (UVB) radiation to stimulate the survival, migration, and tube-forming activity of ASCs in vitro; (2) the ability of UVB preconditioning to enhance the hair growth-promoting capacity of ASCs in vivo; and (3) the mechanism of action for ASC stimulation by UVB. Although high-dose UVB decreased the proliferation of ASCs, low-dose (10 or 20 mJ/cm(2)) treatment increased their survival, migration, and tube-forming activity. In addition, low-dose UVB upregulated the expression of ASC-derived growth factors, and a culture medium conditioned by UVB-irradiated ASCs increased the proliferation of dermal papilla and outer root sheet cells. Notably, injection of UVB-preconditioned ASCs into C(3)H/HeN mice significantly induced the telogen-to-anagen transition and increased new hair weight in vivo. UVB treatment significantly increased the generation of reactive oxygen species (ROS) in cultured ASCs, and inhibition of ROS generation by diphenyleneiodonium chloride (DPI) significantly attenuated UVB-induced ASC stimulation. Furthermore, NADPH oxidase 4 (Nox4) expression was induced in ASCs by UVB irradiation, and Nox4 silencing by small interfering RNA, like DPI, significantly reduced UVB-induced ROS generation. These results suggest that the primary involvement of ROS generation in UVB-mediated ASC stimulation occurs via the Nox4 enzyme. This is the first indication that a low dose of UVB radiation and/or the control of ROS generation could potentially be incorporated into a novel ASC preconditioning method for hair regeneration.

Ultraviolet B-induced LGI3 secretion protects human keratinocytes

Leucine-rich glioma inactivated 3 (LGI3) is known to be expressed mainly in the brain. However, the expression and physiological roles of LGI3 in skin cells remain unknown. In this study, it was found for the first time that LGI3 is expressed mostly by normal human keratinocytes. Furthermore, ELISA analysis showed that HaCaT human keratinocytes increased LGI3 secretion after exposure to ultraviolet B (UVB) in a time- and dose-dependent manner. We next investigated the possible role of LGI3 in keratinocytes. LGI3 (50 ng/ml) increased survival of HaCaT cells by 20% after UVB irradiation (150 mJ/cm(2) ). It was also found that LGI3 stimulates the phosphorylation of Akt, which is involved in the cell survival-signalling cascade. Furthermore, LGI3 led to the phosphorylation of MDM2 and subsequent p53 degradation. Taken together, the data suggest that LGI3 may regulate p53 levels and that keratinocyte-derived LGI3 may act as a novel cytokine for skin homoeostasis.

Activation of vasculogenic progenitor cells by ent-16α,17-dihydroxy-kauran-19-oic acid

Vasculogenic progenitor cells (VPCs) circulate in the blood and have the ability to differentiate into endothelial cells that make up the lining of blood vessels. Therefore, VPC transplantation is a new strategy for the treatment of ischemic diseases. Because priming/preconditioning of VPCs before transplantation enhances their regenerative potential, the present study investigated whether ent-16α,17-dihydroxy-kauran-19-oic acid (DHK) isolated from Siegesbeckia pubescens could stimulate/activate VPCs in vitro. Therefore, the effect of DHK (1-100 µM concentration) on the proliferation, migration, and tube forming of VPCs was examined in various systems, and related signaling pathways were identified. DHK treatment significantly increased the proliferation, migration, and tube formation of VPCs in a dose-dependent manner. Phosphorylation of extracellular signal-regulated kinase (ERK)1/2 and Akt was significantly increased by DHK, but chemical inhibitors against ERK1/2 (U0126) and Akt (LY294002) significantly attenuated DHK-enhanced proliferation, migration, and tube formation of VPCs. Collectively, these results indicated that DHK shows promise as a novel VPC primer/activator.

Indole-3-carbinol and ultraviolet B induce apoptosis of human melanoma cells via down-regulation of MITF

We investigated the mechanism of indole-3-carbinol (13C)/ultraviolet B (UVB)-induced apoptosis using SK-MEL-2 and SK-MEL-5 human melanoma cells. 13C/UVB significantly reduced the viability of SK-MEL-2 cells, whereas it had little influence on SK-MEL-5 cells. Correspondingly, cell cycle analysis showed that 13C/UVB induced a clear increase in the sub-G0/G1 phase in SK-MEL-2 cells. Furthermore, 13C/UVB activated caspase-9, caspase-8, caspase-3, and Bid and caused the cleavage of poly(ADP-ribose) polymerase (PARP) in SK-MEL-2 cells. In contrast, 13C/UVB showed no effects on the apoptotic signaling pathways in SK-MEL-5 cells. Moreover, we found that 13C down-regulated the microphthalmia-associated transcription factor (MITF) in SK-MEL-2 cells, but not in SK-MEL-5 cells. Next, to investigate the involvement of MITF in 13C/UVB-induced apoptosis, MITF silencing was conducted using small interfering RNA (siRNA) for MITF in SK-MEL-5 cells. Interestingly, 13C/UVB dramatically decreased the viability of MITF-down-regulated SK-MEL-5 cells. These results indicate that MITF plays a critical role in melanoma cell survival.

Indole-3-carbinol inhibits prostate cancer cell migration via degradation of beta-catenin

We determined whether indole-3-carbinol (I3C) could affect DU145 human prostate carcinoma cell migration to prevent the development and progression of prostate cancer. Although previous studies have shown anticancer properties of I3C in various cancer cell lines, it has not been determined how I3C regulates epidermal growth factor (EGF)-induced migration and related signaling pathways. DU145 cells were treated with I3C (100 microM) in the absence or presence of EGF (10 ng/ml). Our results showed that I3C significantly inhibited DU145 cell migration with and without EGF stimulation. It has been reported that the beta-catenin signaling pathway controls androgen receptor (AR)-mediated prostate cancer progression, which plays a key role in the metastasis of prostate cancer. Western blot analysis demonstrated that I3C led to the phosphorylation of beta-catenin and subsequent degradation of beta-catenin in the absence and presence of EGF. In contrast, I3C did not have any effect on the expression of beta-catenin mRNA. From these results, we suggest that I3C inhibits EGF (dependent or independent)-induced DU145 cell migration through beta-catenin degradation.

Neuron-specific expression of scratch genes during early zebrafish development

Scratch (scrt) genes are neural-specific in mammals, but their homologues have not been well studied in non-mammalian vertebrates. In this report, we isolated three zebrafish scrt genes, scratch1a (scrt1a), scratch1b (scrt1b), and scratch2 (scrt2), which belong to the Snail superfamily of zinc finger transcription factors. Spatiotemporal expression analysis revealed that scrt1a and scrt2 were initially detected in the central nervous system (CNS) during early somitogenesis while scrt1b was first detectable in neuronal clusters in the brain during late somitogenesis. Interestingly, scrt-expressing cells largely overlapped with huC-positive differentiating neurons and partially with neurogenin1-positive neuronal precursor cells. In addition, scrt-expressing cells were dramatically increased in mind bomb, a neurogenic mutant. Taken together, these results suggest that each zebrafish scrt gene is specifically expressed in neuronal cells and may be involved in differentiation of distinct neuronal populations in the vertebrate nervous system.

Arbutin inhibits TCCSUP human bladder cancer cell proliferation via up-regulation of p21

Arbutin is a glycosylated hydroquinone extracted from the bearberry plant (Arctostaphylos species). In the present study, we determined the effects of arbutin on TCCSUP human bladder carcinoma cell proliferation. Arbutin did not exhibit any cytotoxic effects in TCCSUP cells at concentrations of < 500 microg/ml. To determine the effects of arbutin on cell proliferation, TCCSUP cells were treated with arbutin at various concentrations, and the cell proliferation was measured using the MTT assay. Arbutin significantly decreased TCCSUP cell proliferation in a concentration- and time-dependent manner. Furthermore, cell cycle analysis revealed that arbutin strongly disrupted the cell cycle in a time-dependent manner. Western blot analysis demonstrated that arbutin led to the inactivation of extracellular signal-regulated kinase (ERK), which is known to critically regulate cell proliferation. In addition, arbutin markedly increased the expression of p21WAF1/CIP1 (p21), which is known to be highly involved in cell cycle regulation. Therefore, this study suggests that arbutin inhibits TCCSUP cell proliferation via ERK inactivation and p21 up-regulation.

Sphingosine-1-phosphate decreases melanin synthesis via microphthalmia-associated transcription factor phosphorylation through the S1P3 receptor subtype

OBJECTIVES

Previously, we reported that sphingosine-1-phosphate (S1P) reduced melanin synthesis. In this study we have investigated S1P receptor-mediated extracellular signal-regulated protein kinase (ERK) activation and microphthalmia-associated transcription factor (MITF) phosphorylation.

METHODS

To examine S1P-induced signalling pathways, electron and confocal microscopic studies, reverse transcription-polymerase chain reaction and Western blot analysis were performed.

KEY FINDINGS

S1P phosphorylated MITF at Ser73, which may have resulted in a MITF mobility shift. Furthermore, 90 kDa ribosomal S6 kinase-1 (RSK-1) phosphorylation was observed after S1P treatment. In addition, PD98059 abrogated the S1P-induced MITF mobility shift and RSK-1 activation. In experiments with MITF mutants, it was shown that dual phosphorylation at Ser73 and Ser409 was indispensable for MITF degradation. We investigated further the actions of S1P on its specific receptors. The results showed that pertussis toxin completely abolished the hypopigmentary effects and ERK pathway activation by S1P, suggesting that S1P regulated melanogenesis via its receptor. The use of specific receptor antagonists indicated that the S1P(3) receptor was dominantly involved in S1P-induced ERK activation and hypopigmentation.

CONCLUSIONS

The results suggested that S1P reduced melanin synthesis via S1P(3) receptor-mediated ERK and RSK-1 activation, and subsequent MITF dual phosphorylation and degradation.

Indole-3-acetic acid/horseradish peroxidase induces apoptosis in TCCSUP human urinary bladder carcinoma cells

Indole-3-acetic acid (IAA) and horseradish peroxidase (HRP) have emerged as a new strategy for cancer treatment. In the present study, we determined the effects of IAA/HRP treatment on TCCSUP human urinary bladder carcinoma cells. It was found that the IAA/HRP combination decreased cell viability of TCCSUP cells in a time- and dose-dependent manner, whereas IAA or HRP alone showed no such effect. In addition, the decreased cell viability was restored by pretreatment with ascorbic acid. To clarify the mechanism of death of TCCSUP cells by IAA/HRP, we investigated the signal transduction pathways related to the apoptosis. It was found that IAA/HRP activates p38 mitogen-activated protein (MAP) kinase and c-Jun N-terminal kinase (JNK). We further investigated the IAA/HRP-mediated apoptotic pathways and showed that IAA/HRP induces caspase-8 and caspase-9 activation, which results in caspase-3 activation and poly(ADP-ribose) polymerase (PARP) cleavage. To further confirm whether IAA/HRP induces apoptotic cell death, we performed a DNA fragmentation assay after IAA/HRP treatment and found that IAA/HRP-treated cells showed typical apoptotic DNA ladder formation. From these results, we suggest that IAA/HRP induces apoptosis of TCCSUP human urinary bladder carcinoma cells via both death receptor-mediated and mitochondrial apoptotic pathways.

Enhanced effects of citrate on UVB-induced apoptosis of B16 melanoma cells

Ultraviolet (UV) radiation is a major risk factor for the development of melanoma. Recent studies have reported that the intake of citrate-containing juices may reduce the risk of cancer. Thus, we investigated the effects of citrate on UVB-irradiated B16 murine melanoma cells. B16 cells had more evident apoptotic features with the combination of citrate/UVB than by citrate or UVB alone; cell death of HaCaT human keratinocytes was not observed with citrate/UVB. Western blot analysis demonstrated that citrate/UVB led to phosphorylation of the stress signaling proteins, such as c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (MAPK). Furthermore, citrate/UVB caused activation of caspase-9/-3 as well as cleavage of poly(ADP-ribose) polymerase (PARP). Correspondingly, cell cycle analysis showed that citrate/UVB clearly increased the sub-G0/G1 phase, which indicated apoptotic cell death of B16 cells. Therefore, our study has demonstrated that sub-lethal doses of citrate enhanced the apoptotic cell death of melanoma cells under UVB irradiation. From these results, we suggest that citrate might reduce the risk of developing melanoma induced by UVB.

Applications of three-dimensionally scanned models in orthodontics

The purpose of this study was to investigate clinical applications of the three-dimensional reverse engineering technologies for the analysis of orthodontic models. The measuring accuracy and the process of the 3D model scanning technique were evaluated with respect to linear, surface and volumetric parameters. Orthodontically induced dentoalveolar changes, which have been traditionally evaluated by cephalometric analysis, were assessed by the registration function of Rapidform 2002, a 3D-reverse modeling software in scanned maxillary casts. Three-dimensional digital models are valuable alternatives to conventional casts for model analysis and also yield information which could previously be gathered only by cephalometric superimposition.

A New 2-Imino-1,3-thiazoline Derivative, KHG22394, Inhibits Melanin Synthesis in Mouse B16 Melanoma Cells

During our on-going attempts to develop a new skin-whitening agent, we identified a novel candidate compound KHG22394, a 2-imino-1,3-thiazoline derivative. Our data show that KHG22394 significantly inhibits melanin production in a dose-dependent manner, but that it does not directly inhibit tyrosinase, the rate limiting melanogenic enzyme. It has been reported that the activation of extracellular signal-regulated kinase (ERK) reduces melanin synthesis by downregulating microphthalmia-associated transcription factor (Mitf). Thus, we examined the effects of KHG22394 on the ERK pathway and found that it induced ERK and 90 kDa ribosomal S6 kinase (RSK-1) activation. Moreover, alpha-melanocyte-stimulating hormone (alpha-MSH) is known to increase melanin biosynthesis by increasing tyrosinase production, and here, we found that alpha-MSH-induced Mitf and tyrosinase increases were inhibited in B16 melanoma cells treated with KHG22394. These findings suggest that the hypopigmentary effect of KHG22394 results from the downregulation of Mitf and subsequently of tyrosinase, although KHG22394 did not inhibit tyrosinase activity directly. Our findings indicate that 2-imino-1,3-thiazoline derivatives are potential skin whitening agents.

Hydrogen peroxide is a mediator of indole-3-acetic acid/horseradish peroxidase-induced apoptosis

Recently, we reported that a combination of indole-3-acetic acid (IAA) and horseradish peroxidase (HRP) induces apoptosis in G361 human melanoma cells. However, the apoptotic mechanism involved has been poorly studied. It is known that when IAA is oxidized by HRP, free radicals are produced, and since oxidative stress can induce apoptosis, we investigated whether reactive oxygen species (ROS) are involved in IAA/HRP-induced apoptosis. Our results show that IAA/HRP-induced free radical production is inhibited by catalase, but not by superoxide dismutase or sodium formate. Furthermore, catalase was found to prevent IAA/HRP-induced apoptotic cell death, indicating that IAA/HRP-produced hydrogen peroxide (H2O2) may be involved in the apoptotic process. Moreover, the antiapoptotic effect of catalase is potentiated by NADPH, which is known to protect catalase. On further investigating the IAA/HRP-mediated apoptotic pathway, we found that the IAA/HRP reaction leads to caspase-3 activation and poly(ADP-ribose) polymerase (PARP) cleavage, which was also blocked by catalase. Additionally, we found that IAA/HRP produces H2O2 and induces peroxiredoxin (Prx) sulfonylation. Consequently, our results suggest that H2O2 plays a major role in IAA/HRP-induced apoptosis.

Indole-3-Acetic Acid/Horseradish Peroxidase-Induced Apoptosis Involves Cell Surface CD95 (Fas/APO-1) Expression

Recently, we showed that a combination of indole-3-acetic acid (IAA) and horseradish peroxidase (HRP) produces hydrogen peroxide (H2O2), and that this leads to the apoptosis of G361 human melanoma cells. In the present study, flow cytometric analysis confirmed that H2O2 is involved the IAA/HRP-induced apoptotic process. We also found that IAA/HRP increases cell surface CD95 (Fas/APO-1) expression, and that this is blocked by catalase treatment. Furthermore, blocking CD95 with a neutralizing antibody significantly restored IAA/HRP-induced apoptosis. In addition, the IAA/HRP-induced activations of CD95 downstream molecules, i.e., caspase-8, Bid, and caspase-3, were also inhibited by catalase. Moreover, a caspase-8 inhibitor significantly blocked IAA/HRP-induced apoptosis. These results indicate that IAA/HRP-induced apoptosis involves a CD95-initiated death receptor signaling pathway initiated by hydrogen peroxide.

Light-Activated Indole-3-Acetic Acid Induces Apoptosis in G361 Human Melanoma Cells

Indole-3-acetic acid (IAA) activation by horseradish peroxidase (HRP) has been suggested as a new cancer therapy. Interestingly, we found that ultraviolet B UVB radiation also can activate IAA and produce free radicals in a dose-dependent manner. In this study, we attempted to identify the free radicals generated by UVB-irradiated IAA (IAAUVB), and to determine whether IAAUVB can induce the apoptosis of G361 human melanoma cells. Since IAA/HRP produces reactive oxygen species (ROS), we examined whether IAAUVB-generated radicals include ROS. Our results show that IAAUVB-induced free radical production is not inhibited by catalase, superoxide dismutase, or sodium formate, indicating that ROS are not generated by IAAUVB. On the other hand, IAAUVB caused lipid peroxidation, and this was blocked by Trolox, a water-soluble vitamin E derivative. Moreover, we found that IAAUVB caused apoptotic cell death and that this was inhibited by a low temperature. We further investigated IAAUVB-mediated apoptotic pathways, and found that IAAUVB causes caspase-8, Bid, caspase-3 activation, and poly (ADP-ribose) polymerase (PARP) cleavage. In addition, these apoptotic pathways were also blocked by low temperature. From these results, we propose that IAAUVB-induced free radicals cause human melanoma cell apoptosis via a death receptor-mediated apoptotic pathway.

Cytoprotective effect of green tea extract and quercetin against hydrogen peroxide-induced oxidative stress

In this study, we evaluated the cytoprotective effects of antioxidative substances in hydrogen peroxide (H2O2) treated Mel-Ab melanocytes. Tested substances include selenium, quercetin, green tea (GT) extract, and several vitamins (ascorbic acid, Trolox, and folic acid). Of these, both quercetin and GT extract were found to have strong cytoprotective effects on H2O2-induced cell death. We also examined additive effects, but no combination of two of any of the above substances was found to act synergistically against oxidative damage in Mel-Ab cells. Nevertheless, a multi-combination of GT extract, quercetin, and folic acid appeared to prevent cellular damage in a synergistic manner, which suggests that combinations of antioxidants may be of importance, and that co-treatment with antioxidants offers a possible means of treating vitiligo, which is known to be related to melanocyte oxidative stress.

Sequence analysis of the Bacillus subtilis 168 chromosome region between the sspC and odhA loci (184 degrees-180 degrees)

The nucleotide sequence of 45,389 bp in the 184 degrees-180 degrees region of the Bacillus subtilis chromosome, containing the cge cluster, which is controlled by the sporulation regulatory protein GerE, was determined. Fifty-four putative ORFs with putative ribosome-binding sites were recognized. Seven of them correspond to previously characterized genes: cgeB, cgeA, cgeC, cgeD, cgeE, ctpA, and odhA. The deduced products of 25 ORFs were found to display significant similarities to proteins in the data banks. We have identified genes involved in detoxification, cell walls, and in the metabolism of biotins, purines, fatty acids, carbohydrates and amino acids. The remaining 22 ORFs showed no similarity to known proteins. Both an attachment site of the SPbeta prophage and 2 new putative DNA replication terminators were identified in this region.

Sonography of the stomach: an in vitro study to determine the anatomic cause of inner hyperechoic and hypoechoic layers of the gastric wall

OBJECTIVE

Sonography of the normal gastric wall delineates five distinct layers: from the luminal side, a first, inner hyperechoic layer; a second, hypoechoic layer; a third, middle hyperechoic layer; a fourth, hypoechoic layer; and a final, outer hyperechoic layer. The anatomic origin of the inner two sonographic layers has been a matter of controversy. To verify the histologic origin of the inner two sonographic layers, we attempted to correlate sonographic and histologic layers of resected gastric specimens. Because we hypothesized that the fluid covering the mucosa and the mucosa may be responsible for the sonographic inner two layers of the stomach, we selected specimens in which the mucosa was sloughed or thickened.

MATERIALS AND METHODS

We selected five resected gastric specimens with ulcerative carcinoma in which the mucosa was totally sloughed, one specimen with a mucosal polyp, and two specimens with a polypoid lesion and partial surface ulceration. The gastric specimens were immersed in normal saline and examined with 5-MHz high-resolution sonographic equipment. Sonographic findings were correlated with gross and microscopic pathologic findings. Two phantoms were immersed in normal saline and examined with the same technique to evaluate the thickness of the sonographic interface between water and phantoms.

RESULTS

The inner hyperechoic layer was constant in thickness, measuring 1 mm, and covered the surface of the normal areas and the areas where the mucosa was lost or thickened. The hypoechoic layer underlying the hyperechoic layer was obliterated where the mucosa was defective and thickened where the mucosa was thickened. The sonographic interface between water and phantoms was 1 mm thick.

CONCLUSION

Our results show that the inner hyperechoic layer of the stomach seen on sonograms is due to echoes arising from the interface between fluid in the gastric lumen and the mucosal surface. The underlying hypoechoic layer is caused by the mucosa itself.