Casein kinase 1α (CK1α), a component of the β-catenin destruction complex, is a critical regulator of Wnt signaling; its ablation induces both Wnt and p53 activation. To characterize the role of CK1α ...(encoded by Csnk1a1) in skin physiology, we crossed mice harboring floxed Csnk1a1 with mice expressing K14–Cre–ERT2 to generate mice in which tamoxifen induces the deletion of Csnk1a1 exclusively in keratinocytes single-knockout (SKO) mice. As expected, CK1α loss was accompanied by β-catenin and p53 stabilization, with the preferential induction of p53 target genes, but phenotypically most striking was hyperpigmentation of the skin, importantly without tumorigenesis, for at least 9 mo after Csnk1a1 ablation. The number of epidermal melanocytes and eumelanin levels were dramatically increased in SKO mice. To clarify the putative role of p53 in epidermal hyperpigmentation, we established K14–Cre–ERT2 CK1α/p53 double-knockout (DKO) mice and found that coablation failed to induce epidermal hyperpigmentation, demonstrating that it was p53-dependent. Transcriptome analysis of the epidermis revealed p53-dependent up-regulation of Kit ligand (KitL). SKO mice treated with ACK2 (a Kit-neutralizing antibody) or imatinib (a Kit inhibitor) abrogated the CK1α ablation-induced hyperpigmentation, demonstrating that it requires the KitL/Kit pathway. Pro-opiomelanocortin (POMC), a precursor of α-melanocyte–stimulating hormone (α-MSH), was not activated in the CK1α ablation-induced hyperpigmentation, which is in contrast to the mechanism of p53-dependent UV tanning. Nevertheless, acute sunburn effects were successfully prevented in the hyperpigmented skin of SKO mice. CK1α inhibition induces skin-protective eumelanin but no carcinogenic pheomelanin and may therefore constitute an effective strategy for safely increasing eumelanin via UV-independent pathways, protecting against acute sunburn.
(1) Background: The autonomic imbalance plays a role in vasovagal syncope (VVS) diagnosed by head-up tilting test (HUT). neuECG is a new method of recording skin electrical signals to simultaneously ...analyze skin sympathetic nerve activity (SKNA) and electrocardiogram. We hypothesize that SKNA is higher in subjects with tilt-positive than tilt-negative and the SKNA surges before syncope. (2) Methods: We recorded neuECG in 41 subjects who received HUT (according to the “Italian protocol”), including rest, tilt-up, provocation and recovery phases. Data were analyzed to determine the average SKNA (aSKNA, μV) per digitized sample. Electrocardiogram was used to calculate standard deviation of normal-to-normal beat intervals (SDNN). The “SKNA-SDNN index” was calculated by rest aSKNA multiplied by the ratio of tilt-up to rest SDNN. (3) Results: 16 of 41 (39%) subjects developed syncope. The aSKNA at rest phase is significantly higher in the tilt-positive (1.21 ± 0.27 µV) than tilt-negative subjects (1.02 ± 0.29 µV) (p = 0.034). There are significant surges and withdraw of aSKNA 30 s before and after syncope (both p ≤ 0.006). SKNA-SDNN index is able to predict syncope (p < 0.001). (4) Conclusion: Higher SKNA at rest phase is associated with positive HUT. The SKNA-SDNN index is a novel marker to predict syncope during HUT.
The antihypertensive drug amiloride is being considered as a tactic to improve cancer therapy including that for chronic myelogenous leukemia. In this study, we show that amiloride modulates the ...alternative splicing of various cancer genes, including Bcl-x, HIPK3, and BCR/ABL, and that this effect is not mainly related to pH alteration, which is a known effect of the drug. Splice modulation involved various splicing factors, with the phosphorylation state of serine-arginine-rich (SR) proteins also altered during the splicing process. Pretreatment with okadaic acid to inhibit protein phosphatase PP1 reversed partially the phosphorylation levels of SR proteins and also the amiloride-modulated yields of Bcl-xs and HIPK3 U(-) isoforms. Genome-wide detection of alternative splicing further revealed that many other apoptotic genes were regulated by amiloride, including APAF-1, CRK, and SURVIVIN. Various proteins of the Bcl-2 family and MAPK kinases were found to be involved in amiloride-induced apoptosis. Moreover, the effect of amiloride on mRNA levels of Bcl-x was demonstrated to translate to the protein levels. Cotreatment of K562 and BaF3/Bcr-AblT315I cells with amiloride and imatinib induced more loss of cell viability than either agent alone. Our findings suggest that amiloride may offer a potential treatment option for chronic myelogenous leukemia either alone or in combination with imatinib.
Metabolic syndrome (MetS) is associated with arrhythmias and cardiovascular mortality. Arrhythmogenesis in MetS results from atrial structural and electrical remodelling. The small-conductance ...Ca2+-activated K+ (SK) currents modulate atrial repolarization and may influence atrial arrhythmogenicity. This study investigated the regulation of SK current perturbed by a high-fat diet (HFD) to mimic MetS.
Thirty mice were divided into two groups that were fed with normal chow (CTL) and HFD for 4 months. Electrocardiography and echocardiography were used to detect cardiac electrical and structure remodelling. Atrial action potential duration (APD) and calcium transient duration (CaTD) were measured by optical mapping of Langendorff-perfused mice hearts. Atrial fibrillation (AF) inducibility and duration were assessed by burst pacing. Whole-cell patch clamp was performed in primarily isolated atrial myocytes for SK current density. The SK current density is higher in atrial myocytes from HFD than in CTL mice (P ≤ 0.037). The RNA and protein expression of SK channels are increased in HFD mice (P ≤ 0.041 and P ≤ 0.011, respectively). Action potential duration is shortened in HFD compared with CTL (P ≤ 0.015). The shortening of the atrial APD in HFD is reversed by the application of 100 nM apamin (P ≤ 0.043). Compared with CTL, CaTD is greater in HFD atria (P ≤ 0.029). Calcium transient decay (Tau) is significantly higher in HFD than in CTL (P = 0.001). Both APD and CaTD alternans thresholds were higher in HFD (P ≤ 0.043), along with higher inducibility and longer duration of AF in HFD (P ≤ 0.023).
Up-regulation of apamin-sensitive SK currents plays a partial role in the atrial arrhythmogenicity of HFD mice.
Tumor endothelial marker 1 (TEM1/CD248) is a transmembrane protein that expresses in mesenchymal lineage derived cells during embryogenesis and becomes undetectable in normal adults after birth. ...Re-expression of TEM1 is found in organ fibrosis, wound healing and cardiac remodeling indicating its potential role in heart failure (HF). The purpose of this study is to explore the role of soluble TEM1 (sTEM1) in patients with HF with reduced ejection fraction.
We examined endomyocardial biopsy specimens from three HF patients and blood samples from 48 patients admitted for acute decompensated HF (age 72 years, men 61.7%). The expression of TEM1 in cardiac tissue and concentrations of sTEM1 in plasma were evaluated. Cultured rat cardiomyocytes (H9c2) and human cardiac fibroblasts (HCF) were stimulated with hypoxia or transforming growth factor beta (TGF-β) to observe the release of sTEM1 into culture media. The conditioned media of hypoxia-stimulated H9c2 cells was harvested and added into cultured cardiac fibroblast to evaluate its biological effect.
Immunofluorescence study of biopsy specimens from three HF patients showed TEM1 expression in cardiomyocytes and cardiac fibroblasts. The plasma level of sTEM1 was significantly higher in patients (0.90 ± 0.23 vs. 0.33 ± 0.10 ng/mL,
= 0.032) with LVEF ≤ 35% compared with those with LVEF 36-49%. The sTEM1 levels had correlations with HF biomarkers of cardiac fibrosis, including growth differentiation factor-15 (GDF-15) and galectin-3. There was a significant increase in sTEM1 levels in the cultured media of H9c2 and HCF after being stressed with hypoxia or TGF-β. The conditioned media derived from hypoxia-stimulated H9c2 cells significantly increased cell proliferation of cardiac fibroblasts. This effect was partially reversed by anti-TEM1 antibody.
This pilot study demonstrated that cardiac TEM1 expression was upregulated in HF. The levels of sTEM1 were significantly higher in HF patients with LVEF ≤ 35% and correlated with other biomarkers of cardiac fibrosis.
study proved that functional sTEM1 was released into cultured media after stressing cardiomyocytes and HCF.
Testicular cancer is fairly rare but can affect fertility in adult males. Leucine-rich repeats- and WD repeat domain-containing protein 1 (LRWD1) is a sperm-specific marker that mainly affects sperm ...motility in reproduction. Our previous study demonstrated the impact of LRWD1 on testicular cancer development; however, the underlying mechanisms remain unclear.
In this study, various plasmids associated with LRWD1 and miR-320a manipulation were used to explore the roles and regulatory effects of these molecules in NT2D1 cellular processes. A Dual-Glo luciferin-luciferase system was used to investigate LRWD1 transcriptional activity, and qRT-PCR and western blotting were used to determine gene and protein expression.
The results suggested that miR-320a positively regulated LRWD1 and positively correlated with NT2D1 cell proliferation but negatively correlated with cell migration and invasion ability. In addition, the miRNA-ribonucleoprotein complex AGO2/FXR1 was shown to be essential in the mechanism by which miR-320a regulates LRWD1 mRNA expression. As miR-320a was required to regulate LRWD1 expression through the AGO2 and FXR1 complex, eEF2 and eLF4E were also found to be involved in miR-320a increasing LRWD1 expression. Furthermore, miR-320a and LRWD1 were responsive to oxidative stress, and NRF2 was affected by the presence of miR-320a in response to ROS stimulation.
This is the first study showing the role of miR-320a in upregulating the testicular cancer-specific regulator LRWD1 and the importance of the AGO2/FXR1 complex in miR-320a-mediated upregulation of LRWD1 during testicular cancer progression.
•A single micromixer composed of double Archimedes-screw adapted to fit in microchannel to generate 3D omnidirectional momentum-changes and multiple jets for enhancing mixing performance.•With the ...spiral conformation, the Archimedes-screw micromixer (ASM) can substantially enhance fluid circulation.•The screw-turn of the ASM was investigated for an optimal design. The quantitative analysis of experimental mixing result shows good agreement with the simulation findings
Recent developments in 3D micromixers promise to accomplish satisfactory mixing for applications in microchemical process, biomicrofluidic analyses, μ-TAS, etc. However, the complicated 3D architecture employed to ensure thorough mixing might reduce fluid circulation due to the space for fluid flowing becomes narrow. In this study, we developed a single 3D multi-manifold micromixer composed of a double-Archimedes-screw for rapidly mixing within a short distance. Archimedes screw is well known for its fluid circulation under stable flow. The mixing strategy is based on split-and-recombination for increasing the interfacial area, and the 3D flow rotation for generating omnidirectional momentum-changes during the fluid propagation. With the spiral conformation, the Archimedes-screw micromixer (ASM) can substantially enhance fluid circulation. Numerical simulations used to help to design the optimal screw-turn show that satisfactory mixing efficiency can achieve at the distance of approximately twice the microchannel width. The ASM characteristics, such as pressure loss, ratio of cross-sections, and Reynolds number (Re) were evaluated. Experimental demonstration by an ASM fabricated by two-photon stereolithography showed mixing result in good agreement with the simulation findings.
A single micromixer composed of double Archimedes-screws adapted to fit rectangular section microchannel to generate 3D omnidirectional momentum-changes and multiple jets for high efficient mixing. Display omitted
AIM： To verify the usefulness of FibroQ for predicting fi brosis in patients with chronic hepatitis C, compared with other noninvasive tests. METHODS： This retrospective cohort study included 237 ...consecutive patients with chronic hepatitis C who had undergone percutaneous liver biopsy before treatment. FibroQ, aspartate aminotransferase （AST）/alanine aminotransferase ratio （AAR）, AST to platelet ratioindex, cirrhosis discriminant score, age-platelet index （API）, Pohl score, FIB-4 index, and Lok＇s model were calculated and compared. RESULTS： FibroQ, FIB-4, AAR, API and Lok＇s model results increased significantly as fibrosis advanced （analysis of variance test： P 〈 0.001）. FibroQ trended to be superior in predicting signifi cant fi brosis score in chronic hepatitis C compared with other noninvasive tests. CONCLUSION： FibroQ is a simple and useful test for predicting signifi cant fi brosis in patients with chronic hepatitis C.
Highlights • Frizzled-3 is constitutively expressed in melanocyte lineage cells. • Wnt3a stimulates the proliferation of melanocyte precursors and melanocytes. • Wnt3a stimulates melanogenesis and ...dendrite formation in melanocytes. • Wnt3a cannot induce c-Kit− melanocyte precursors to express c-Kit. • Wnt3a does not affect migration of melanocyte precursors and melanocytes.
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