Assessment of the (Pro)renin Receptor Protein Expression in Organs.

The (pro)renin receptor ((P)RR) is an essential component of the renin-angiotensin system (RAS) as a specific single-pass transmembrane receptor for prorenin and renin and has now emerged as a multifunctional protein implicated in a wide variety of developmental and physio-pathological processes and pathways. The (P)RR may be of pathological significance in metabolic syndrome. The (P)RR has received much consideration; substantial efforts have been made to understand the localization, regulation, and function of the (P)RR at both a molecular and system level. (P)RR regulation of cell function depends on whether it is intact or cleaved into its constituent forms. Therefore, the present chapter describes immunohistochemical approaches to examine the expression of (P)RR in various organs. It was shown that different molecular forms of (P)RR could be present in different tissue compartments in almost all organs. Among them, the liver has high PRR activity. Our findings could elucidate more detailed distribution of different (P)RR molecular forms in different organs, which could provide useful information to further investigate the pathophysiological mechanisms of the development of various diseases in the future.

2024 Guidelines of the Taiwan Society of Cardiology on the Primary Prevention of Atherosclerotic Cardiovascular Disease --- Part I.

Atherosclerotic cardiovascular disease (ASCVD) is one of the leading causes of death worldwide and in Taiwan. It is highly prevalent and has a tremendous impact on global health. Therefore, the Taiwan Society of Cardiology developed these best-evidence preventive guidelines for decision-making in clinical practice involving aspects of primordial prevention including national policies, promotion of health education, primary prevention of clinical risk factors, and management and control of clinical risk factors. These guidelines cover the full spectrum of ASCVD, including chronic coronary syndrome, acute coronary syndrome, cerebrovascular disease, peripheral artery disease, and aortic aneurysm. In order to enhance medical education and health promotion not only for physicians but also for the general public, we propose a slogan (2H2L) for the primary prevention of ASCVD on the basis of the essential role of healthy dietary pattern and lifestyles: "Healthy Diet and Healthy Lifestyles to Help Your Life and Save Your Lives". We also propose an acronym of the modifiable risk factors/enhancers and relevant strategies to facilitate memory: " ABC2D2EFG-I'M2 ACE": Adiposity, Blood pressure, Cholesterol and Cigarette smoking, Diabetes mellitus and Dietary pattern, Exercise, Frailty, Gout/hyperuricemia, Inflammation/infection, Metabolic syndrome and Metabolic dysfunction-associated fatty liver disease, Atmosphere (environment), Chronic kidney disease, and Easy life (sleep well and no stress). Some imaging studies can be risk enhancers. Some risk factors/clinical conditions are deemed to be preventable, and healthy dietary pattern, physical activity, and body weight control remain the cornerstone of the preventive strategy.

Design of Tetrazolium Cations for the Release of Antiproliferative Formazan Chelators in Mammalian Cells.

Cancer cells generally present a higher demand for iron, which plays crucial roles in tumor progression and metastasis. This iron addiction provides opportunities to develop broad spectrum anticancer drugs that target iron metabolism. In this context, prochelation approaches are investigated to release metal-binding compounds under specific conditions, thereby limiting off-target toxicity. Here, we demonstrate a prochelation strategy inspired by the bioreduction of tetrazolium cations widely employed to assess the viability of mammalian cells. We designed a series of tetrazolium-based compounds for the intracellular release of metal-binding formazan ligands. The combination of reduction potentials appropriate for intracellular reduction and an N-pyridyl donor on the formazan scaffold led to two effective prochelators. The reduced formazans bind as tridentate ligands and stabilize low-spin Fe(II) centers in complexes of 2:1 ligand-to-metal stoichiometry. The tetrazolium salts are stable in blood serum for over 24 h, and antiproliferative activities at micromolar levels were recorded in a panel of cancer cell lines. Additional assays confirmed the intracellular activation of the prochelators and their ability to affect cell cycle progression, induce apoptotic death, and interfere with iron availability. Demonstrating the role of iron in their intracellular effects, the prochelators impacted the expression levels of key iron regulators (i.e., transferrin receptor 1 and ferritin), and iron supplementation mitigated their cytotoxicity. Overall, this work introduces the tetrazolium core as a platform to build prochelators that can be tuned for activation in the reducing environment of cancer cells and produce antiproliferative formazan chelators that interfere with cellular iron homeostasis.

Zinc deficiency associated with cutaneous toxicities induced by epidermal growth factor receptor tyrosine kinase inhibitor therapy in patients with lung adenocarcinoma.

PURPOSE: Cutaneous toxicities are common adverse effects following epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) therapy. Zinc deficiency causes diverse diseases, including skin toxicities. Therefore, this study aimed to investigate the role of zinc deficiency in patients with EGFR-TKI-induced skin toxicities. EXPERIMENTAL DESIGN: This retrospective study enrolled 269 patients with diverse skin disorders who visited our hospital between January 2016 and December 2017. The skin toxicity severities and plasma zinc levels of 101 EGFR-TKI-treated cancer patients were analysed and compared with those of 43 non-EGFR-TKI-treated cancer patients and 125 patients without cancer but presenting cutaneous manifestations. Additionally, the role of zinc in erlotinib-induced skin eruptions was established in a 14-day-murine model. Clinical features were further evaluated following systemic zinc supplementation in EGFR-TKI-treated cancer patients. RESULTS: EGFR-TKI-treated patients demonstrated severe cutaneous manifestations and a significant decrease in plasma zinc levels than those of the control groups. The serum zinc level and Common Terminology Criteria for Adverse Events (CTCAE) 5.0 grading of EGFR-TKI-induced skin toxicities showed a significant negative correlation (r = -0.29; p < 0.0001). Moreover, erlotinib treatment decreased the plasma zinc levels and induced periorificial dermatitis in rats confirming zinc deficiency following EGFR-TKI treatment. Zinc supplementation to the EGFR-TKI-treated cancer patients showed a significant decrease in the CTCEA grading (p < 0.0005 for mucositis and p < 0.0.0001 for all other cases) after 8 weeks. CONCLUSIONS: Skin impairment following EGFR-TKI therapy could be ameliorated through zinc supplementation. Thus, zinc supplementation should be considered for cancer patients undergoing EGFR-TKI therapy.

Design Method of Three-Component Optic Fiber Balance Based on Fabry-Perot Displacement Sensor.

This article proposes a new type of three-component optic fiber balance based on Fabry-Perot displacement measurement technology based on the structure of the pulse wind tunnel balance. This paper systematically introduces the force measurement principle and design process of a three-component optic fiber balance and conducts relevant simulation analysis and experimental verification. The simulation results show that the Fabry-Perot sensor can achieve significant sensitivity to cavity length changes, and when used in existing balance structures, sensitivity gains can be achieved by changing the probe height without the need to modify the original structure of the balance. Finally, the feasibility of the design method was verified through calibration experiments: the optic fiber balance has high sensitivity and good linearity compared to simulation sensitivity, the error is less than 6%, and the calibration accuracy of each component is better than 0.13%, which is better than the existing traditional strain balance (0.37%). The pulse wind tunnel force measurement test has a short test time and a large model mass, and the balance needs to have a large stiffness to meet the short-term force measurement requirements. The introduction of more sensitive optic fiber balance force measurement technology is expected to solve the contradiction between the stiffness and sensitivity of force measurement systems.

Thiol-Reactive Arylsulfonate Masks for Phenolate Donors in Antiproliferative Iron Prochelators.

Tridentate thiosemicarbazones, among several families of iron chelators, have shown promising results in anticancer drug discovery because they target the increased need for iron that characterizes malignant cells. Prochelation strategies, in which the chelator is released under specific conditions, have the potential to avoid off-target metal binding (for instance, in the bloodstream) and minimize unwanted side effects. We report a prochelation approach that employs arylsulfonate esters to mask the phenolate donor of salicylaldehyde-based chelators. The new prochelators liberate a tridentate thiosemicarbazone intracellularly upon reaction with abundant nucleophile glutathione (GSH). A 5-bromo-substituted salicylaldehyde thiosemicarbazone (STC4) was selected for the chelator unit because of its antiproliferative activity at low micromolar levels in a panel of six cancer cell lines. The arylsulfonate prochelators were assessed in vitro with respect to their stability, ability to abolish metal binding, and reactivity in the presence of GSH. Cell-based assays indicated that the arylsulfonate-masked prochelators present higher antiproliferative activities relative to the parent compound after 24 h. The activation and release of the chelator intracellularly were corroborated by assays of cytosolic iron binding and iron supplementation effects as well as cell cycle analysis. This study introduces the 1,3,4-thiadiazole sulfonate moiety to mask the phenolate donor of an iron chelator and impart good solubility and stability to prochelator constructs. The reactivity of these systems can be tuned to release the chelator at high glutathione levels, as encountered in several cancer phenotypes.

High-Entropy van der Waals Materials Formed from Mixed Metal Dichalcogenides, Halides, and Phosphorus Trisulfides.

The charge, spin, and composition degrees of freedom in a high-entropy alloy endow it with tunable valence and spin states, infinite combinations, and excellent mechanical performance. Meanwhile, the stacking, interlayer, and angle degrees of freedom in a van der Waals material bring to it exceptional features and technological applications. Integration of these two distinct material categories while keeping their merits would be tempting. On the basis of this heuristic thinking, we design and explore a new range of materials (i.e., dichalcogenides, halides, and phosphorus trisulfides) with multiple metallic constitutions and intrinsic layered structure, which are coined as high-entropy van der Waals materials. Millimeter-scale single crystals with a homogeneous element distribution can be efficiently acquired and easily exfoliated or intercalated in this materials category. Multifarious physical properties such as superconductivity, magnetic ordering, metal-insulator transition, and corrosion resistance have been exploited. Further research based on the concept of high-entropy van der Waals materials will enrich the high-throughput design of new systems with intriguing properties and practical applications.

Iron Complexes of an Antiproliferative Aroyl Hydrazone: Characterization of Three Protonation States by Electron Paramagnetic Resonance Methods.

Tridentate aroyl hydrazones are effective metal chelators in biological settings, and their activity has been investigated extensively for medicinal applications in metal overload, cancer, and neurodegenerative diseases. The aroyl hydrazone motif is found in the recently reported prochelator (AH1-S)2, which has shown antiproliferative proapoptotic activity in mammalian cancer cell lines. Intracellular reduction of this disulfide prochelator leads to the formation of mercaptobenzaldehyde benzoylhydrazone chelator AH1 and to iron sequestration, which in turn impacts cell growth. Herein, we investigate the iron coordination chemistry of AH1 to determine the structural and spectroscopic properties of the iron complexes in the solid state and in solution. A neutral iron(III) complex of 2:1 ligand-to-metal stoichiometry was isolated and characterized fully to reveal two different binding modes for the tridentate AH1 ligand. Specifically, one ligand binds in the monoanionic keto form, whereas the other ligand coordinates as a dianionic enolate. Continuous-wave electron paramagnetic resonance experiments in frozen solutions indicated that this neutral complex is one of three low-spin iron(III) complexes observed depending on the pH of the solution. Electron spin echo envelope modulation (ESEEM) experiments allowed assignment of the three species to different protonation states of the coordinated ligands. Our ESEEM analysis provides a method to distinguish the coordination of aroyl hydrazones in the keto and enolate forms, which influences both the ligand field and overall charge of the complex. As such, this type of analysis could provide valuable information in a variety of studies of iron complexes of aroyl hydrazones, ranging from the investigation of spin-crossover behavior to tracking of their distribution in biological samples.

Inhibition of Advanced Glycation End Products Formation Attenuates Cardiac Electrical and Mechanical Remodeling and Vulnerability to Tachyarrhythmias in Diabetic Rats.

Diabetic patients with cardiomyopathy show a higher incidence of arrhythmias and sudden death. Chronic hyperglycemia induces the formation of advanced glycation end products (AGEs), which contribute to the pathogenesis of diabetic cardiomyopathy. This study investigated whether inhibition of AGEs formation by aminoguanidine (AG) could prevent cardiac electromechanical and arrhythmogenic remodeling in diabetes mellitus. Streptozotocin-induced diabetic rats received AG (100 mg/kg daily, i.p.) or vehicle (normal saline, i.p.) for 5 weeks. The rats underwent hemodynamic recording to evaluate cardiac function, and heart preparations were used to determine the electrical, mechanical, and biochemical functions. In vitro high glucose-induced AGEs formation, reactive oxygen species (ROS) generation, and action potential changes were examined in HL-1 atrial cells. AG treatment improved the diabetes-induced depression in left ventricular pressure and the relaxation rate, and normalized the prolongation of QTc intervals in anesthetized rats. AG reduced the vulnerabilities to atrial and ventricular tachyarrhythmias in perfused diabetic hearts. AG normalized the prolonged action potential duration in diabetic atrial and ventricular muscles, which was correlated with the restoration of both transient outward (I to) and steady-state outward (I SS) K+ current densities in cardiomyocytes. The abnormal kinetics of Ca2+ transients and contraction were reversed in cardiomyocytes from AG-treated diabetic rats, along with parallel preservation of sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA2a) expression. Furthermore, ex vivo and in vitro studies showed AG attenuated AGEs and ROS formation. Thus, long-term administration of AG ameliorated cardiac electromechanical remodeling and arrhythmogenicity in diabetic rats and may present an effective strategy for the prevention of diabetes-associated arrhythmias.

A Novel DES L115F Mutation Identified by Whole Exome Sequencing is Associated with Inherited Cardiac Conduction Disease.

Inherited cardiac conduction disease (CCD) is rare; it is caused by a large number of mutations in genes encoding cardiac ion channels and cytoskeletal proteins. Recently, whole-exome sequencing has been successfully used to identify causal mutations for rare monogenic Mendelian diseases. We used trio-based whole-exome sequencing to study a Chinese family with multiple family members affected by CCD, and identified a heterozygous missense mutation (c.343C>T, p.Leu115Phe) in the desmin (DES) gene as the most likely candidate causal mutation for the development of CCD in this family. The mutation is novel and is predicted to affect the conformation of the coiled-coil rod domain of DES according to structural model prediction. Its pathogenicity in desmin protein aggregation was further confirmed by expressing the mutation, both in a cellular model and a CRISPR/CAS9 knock-in mouse model. In conclusion, our results suggest that whole-exome sequencing is a feasible approach to identify candidate genes underlying inherited conduction diseases.

Crusade Microcatheter-Facilitated Reverse Wire Technique for Revascularization of Bifurcation Lesions of Coronary Arteries.

BACKGROUND: This study aims to analyze the lesion characteristics of bifurcations that required reverse wire technique and the efficacy and safety of this technique in approaching branches with a highly angulated take-off. METHODS: We enrolled patients in whom reverse wire technique was used after failed conventional antegrade wiring with the support of a Crusade catheter. The study endpoints were the technical success defined as succeeding in sending the reversely bent wire to the targeted branches without complications and the procedural success defined as succeeding in revascularization of the bifurcation lesions without complications. RESULTS: Among 158 patients with bifurcation lesions undergoing percutaneous coronary intervention using a Crusade catheter to facilitate wiring, 23 (14.6%) requiring the reverse wire technique in an attempt to access branches of the bifurcation lesions with an acutely angulated take-off were enrolled for analysis. The obtainable angle of take-off was 162.9 ± 4.7 degrees. For the parent vessel, the ostium of the targeted branch, and nontargeted branch, the minimal luminal diameters were 0.3 ± 0.5 mm, 0.4 ± 0.2 mm, and 1.8 ± 0.5 mm, respectively; the diameter stenosis were 88.8 ± 18.5%, 83.0 ± 7.3%, and 32.0 ± 14.5%, respectively. Technical and procedural success was achieved in 22 cases (96% for both). CONCLUSIONS: We showed in the present study that the reverse wire technique is effective and safe for approaching highly angulated branches of bifurcation lesions and consequently for complete revascularization of difficult bifurcation lesions.

Perceptions about eating experiences of low-literate older adults with heart disease: a qualitative study.

AIMS: To explore perceptions of low-literate older adults with heart disease about their eating experiences. BACKGROUND: Heart disease has been closely linked with nutrition, and nutritional status is poor in patients with limited education, but no studies have explored the eating experiences of low-literate adults with heart disease. DESIGN: Qualitative descriptive study. METHODS: Data were collected in tape-recorded semi-structured interviews from March-June 2012. A convenience sample of 13 low-literate older adults with heart disease was recruited from a cardiovascular ward of a medical centre in northern Taiwan. Participants were recruited until findings reached saturation and data were analysed using qualitative content analysis. FINDINGS: Analysis of participants' interview data on eating experiences identified three main categories: (1) eating-related hardships because of low literacy; (2) eating adjustments due to low literacy; and (3) misinformation about dietary modifications for heart disease. CONCLUSION: Because of their low literacy, these older adults had difficult life experiences, gained inappropriate or inadequate eating information and held a passive, fatalistic perspective about eating with heart disease. Healthcare practitioners caring for this population need to appreciate their unique eating challenges and respect their eating customs. Nurses could play a greater role in educating and supporting low-literate older adults in selecting appropriate foods and preparing meals. Strategies to help this population learn to select, prepare and cook their food should be easy and practical, using specific symbols, concrete signs and simple labels.

Clinicopathologic analysis of coxsackievirus a6 new variant induced widespread mucocutaneous bullous reactions mimicking severe cutaneous adverse reactions.

BACKGROUND: The cutaneous manifestations of human enterovirus (HEV) infection are usually limited, such as hand-foot-mouth disease. By comparison, Stevens-Johnson syndrome (SJS) is a life-threatening severe cutaneous adverse reaction (SCAR), mainly caused by drugs. During the HEV outbreaks in 2010-2012 in Taiwan, we identified 21 patients who developed widespread blistering mucocutaneous reactions without any suspected drug causality. METHODS: We screened possible pathogen(s) for detecting human herpes virus (HHV1-HHV7), HEV, or Mycoplasma pneumoniae infections using throat swab virus cultures, real-time PCR, DNA sequencing, immunochemistry and electron microscopy analyses. RESULTS: Coxsackievirus A6 (CVA6) DNA was identified in the blistering skin lesions in 6 of 21 patients. Cytotoxic T lymphocytes and natural killer cells expressing granulysin predominantly infiltrated into the skin lesions, sharing the histopathological features with SJS. Intact CVA6 viral particles were identified in the blister fluids and skin lesions by electron microscopy. The phylogenetic analysis of the viral genome showed the CVA6 DNA sequence sharing higher similarity (97.6%-98.1%) to CVA6 strains reported from Finland at 2008. CONCLUSIONS: This study identifies a new variant of CVA6 as the causative agent for severe mucocutaneous blistering reactions mimicking SCAR. An awareness of this unusual presentation of HEV infection is needed in the epidemic area.

Quinoline-based tetrazolium prochelators: formazan release, iron sequestration, and antiproliferative efficacy in cancer cells.

Iron-binding strategies in anticancer drug design target the key role of iron in cancer growth. The incorporation of a quinoline moiety in the design of tetrazolium-based prochelators facilitates their intracellular reduction/activation to iron-binding formazans. The new prochelators are antiproliferative at submicromolar levels, induce apoptosis and cell cycle arrest, and impact iron signaling in cancer cells.

Risk of myocardial infarction among patients with gout: a nationwide population-based study.

OBJECTIVE: To investigate the association between gout and myocardial infarction (MI) in a representative cohort in Taiwan. METHODS: Data were collected from the Taiwan National Health Insurance database. Adults >20 years of age without history of MI were included. Patients were considered to have gout if they received a diagnosis of gout requiring medical treatment. Multivariate Cox proportional hazards models were used to evaluate the risk of MI in gout patients. RESULTS: Of the 704 503 patients included, 26 556 (3.8%) had gout. In total, 3718 (with gout, n = 463; without gout, n = 3255) patients had an MI, 299 (with gout, n = 35; without gout, n = 264) of whom died. The incidence of MI was 2.20 and 0.60 per 1000 patient-years in individuals with and without gout, respectively (log-rank test, P < 0.001). After adjustment for age, sex and history of diabetes mellitus, hypertension, coronary heart disease (CHD), stroke and end-stage renal disease, gout was associated with MIs [hazard ratio (HR), 1.23] and non-fatal MIs (HR, 1.26). In individuals without cardiovascular risk factors, gout was associated with MIs (HR 1.84; 95% CI 1.51, 2.24) and non-fatal MIs (HR 1.80; 95% CI 1.49, 3.95), after adjustment for age and sex. Moreover, in our study population, the HRs for MI decreased as age increased. CONCLUSION: Gout is an independent risk factor for MI, and the increased risk of MI is present even in young people and those without cardiovascular risk factors.

Transdermal delivery of three vitamin C derivatives by Er:YAG and carbon dioxide laser pretreatment.

The objective of this study was to investigate the effects of two lasers (Er:YAG and CO2) in enhancing skin permeation of three vitamin C derivatives, L-ascorbic acid 2-phosphate sesquimagnesium salt (MAP-1), magnesium L-ascorbic acid-2-phosphate (MAP-2), and 2-phospho-L-ascorbic acid trisodium salt (SAP). Dorsal skin of 1-week-old pathogen-free pigs was used for this in vitro study. Changes in permeation in laser-treated skin treated by the lasers were examined by confocal scanning electron microscopy. Transdermal flux of vitamin C derivatives was examined with a Franz diffusion cell. Fluxes of MAP-1, MAP-2, and SAP across Er:YAG laser-treated skin were 15-27-fold, 48-123-fold, and 22-56-fold higher, respectively, than their fluxes across intact skin. The fluxes of MAP-1, MAP-2, and SAP across CO2 laser-treated skin were 28-36-fold, 116-156-fold, and 79-102-fold higher, respectively, than their fluxes across intact skin. Optimal fluency for the Er:YAG laser was 3.8 J/cm(2) for MAP-1 and 5 J/cm(2) for MAP-2 and SAP. Optimal fluency for the CO2 laser was 5 W for all three derivatives. In conclusion, optimal fluency for all derivatives was 5 W for the CO2 laser and 3.8 to 5 J/cm(2) for the Er:YAG laser.

Application of Self-Assembled Polyarylether Substrate in Flexible Organic Light-Emitting Diodes.

The structure used in this study is as follows: substrate/PMMA/ZnS/Ag/MoO3/NPB/Alq3/LiF/Al. Here, PMMA serves as the surface flattening layer, ZnS/Ag/MoO3 as the anode, NPB as the hole injection layer, Alq3 as the emitting layer, LiF as the electron injection layer, and aluminum as the cathode. The properties of the devices with different substrates were investigated using P4 and glass, developed in the laboratory, as well as commercially available PET. After film formation, P4 creates holes on the surface. The light field distribution of the device was calculated at wavelengths of 480 nm, 550 nm, and 620 nm using optical simulation. It was found that this microstructure contributes to light extraction. The maximum brightness, external quantum efficiency, and current efficiency of the device at a P4 thickness of 2.6 µm were 72,500 cd/m2, 1.69%, and 5.68 cd/A, respectively. However, the maximum brightness of the same structure with PET (130 µm) was 9500 cd/m2. The microstructure of the P4 substrate was found to contribute to the excellent device performance through analysis of the AFM surface morphology, film resistance, and optical simulation results. The holes formed by the P4 substrate were created solely by spin-coating the material and then placing it on a heating plate to dry, without any special processing. To confirm the reproducibility of the naturally formed holes, devices were fabricated again with three different emitting layer thicknesses. The maximum brightness, external quantum efficiency, and current efficiency of the device at an Alq3 thickness of 55 nm were 93,400 cd/m2, 1.7%, and 5.6 cd/A, respectively.

Fractional carbon dioxide laser treatment to enhance skin permeation of ascorbic acid 2-glucoside with minimal skin disruption.

BACKGROUND: Topical treatment with vitamin C has been used to treat photoaged skin and as a skin whitener, but no standard procedure exists for percutaneous delivery. OBJECTIVE: To compare skin histology and the permeation of ascorbic acid 2-glucoside (AA2G) after fractional and conventional carbon dioxide (CO(2) ) laser pretreatment. METHODS: The effect on porcine skin of treatment with different strengths of fractional and conventional CO(2) laser treatment was examined using scanning electron microscopy and transmission electron microscopy. Permeation of AA2G through porcine skin was tested in vitro using a Franz diffusion chamber. In vivo changes in fluorescein thiocyanate permeability in nude mice were examined using confocal laser scanning microscopy. RESULTS: Fractional CO(2) laser treatment with four or fewer passes caused less disruption than conventional laser treatment at the same fluence. AA2G permeation using four passes of fractional laser treatment was similar to that seen with conventional CO(2) laser treatment of the same fluence. Changes in permeability and in depth of permeation were higher with conventional than fractional laser treatment. CONCLUSION: Fractional CO(2) laser treatment can cause similar transdermal delivery of AA2G to conventional laser treatment with less skin disruption and a different pattern of histologic change.

Aroylhydrazone Glycoconjugate Prochelators Exploit Glucose Transporter 1 (GLUT1) to Target Iron in Cancer Cells.

Glycoconjugation strategies in anticancer drug discovery exploit the high expression of glucose transporters in malignant cells to achieve preferential uptake and hence attractive pharmacological characteristics of increased therapeutic windows and decreased unwanted toxicity. Here we present the design of glycoconjugated prochelators of aroylhydrazone AH1, an antiproliferative scavenger that targets the increased iron demand of rapidly proliferating malignant cells. The constructs feature a monosaccharide (d-glucose, d-glucosamine, or glycolytic inhibitor 2-deoxy-d-glucose) connected at the C2 or C6 position via a short linker, which masks the chelator through a disulfide bond susceptible to intracellular reduction. Cellular assays showed that the glycoconjugates rely on the GLUT1 transporter for uptake, lead to intracellular iron deprivation, and present antiproliferative activity. Ectopic overexpression of GLUT1 in malignant and normal cells increased the uptake and toxicity of the glycoconjugated prochelators, demonstrating that these compounds are well suited for targeting cells overexpressing glucose transporters and therefore for selective iron sequestration in malignant cells.

Candesartan Cilexetil Attenuates Arrhythmogenicity Following Pressure Overload in Rats via the Modulation of Cardiac Electrical and Structural Remodeling and Calcium Handling Dysfunction.

Background Cardiac hypertrophy is associated with abnormal electrophysiology and increased arrhythmia risk. This study assessed whether candesartan cilexetil, an angiotensin II type 1 receptor blocker, could suppress arrhythmogenecity by attenuating cardiac electrical remodeling and calcium mishandling in rats with pressure-overload hypertrophy. Methods and Results Male Sprague-Dawley rats were randomly subjected to abdominal aorta banding or sham procedure and received either candesartan cilexetil (3.0 mg/kg per day) or vehicle by gavage for 5 weeks. Pressure overload was characterized by compensated left ventricular (LV) hypertrophy and fibrosis, increased LV pressure and its decay time, and prolonged corrected QT interval, all of which were attenuated by candesartan cilexetil treatment. Candesartan cilexetil-treated banded rat hearts displayed shorter QT intervals and lower vulnerability to atrial and ventricular tachyarrhythmias than vehicle-treated banded hearts. Candesartan cilexetil prevented banding-induced prolonged action potential duration and reduced the occurrence of triggered activity in LV papillary muscles. In addition, the prolonged time to 50% cell relengthening and calcium transient decay time were normalized in LV myocytes from candesartan cilexetil-treated banded rats, along with a normalization of decreased SERCA2a (sarco[endo]plasmic reticulum calcium-ATPase) expression in LV tissues. Furthermore, candesartan cilexetil normalized depressed transient outward potassium current densities and protein and mRNA levels of both voltage-gated potassium 4.2 and 4.3 channel subunits (Kv4.2 and Kv4.3) in banded rats. Conclusions Candesartan cilexetil protects the heart from pressure overload-induced adverse electrical remodeling by preserving potassium channel densities. In addition, calcium handling and its molecular regulation also improved after treatment. These beneficial effects may contribute to a lower susceptibility to arrhythmias in hearts from candesartan cilexetil-treated pressure-overloaded rats.