Porphyran Attenuates Neuronal Loss in the Hippocampal CA1 Subregion Induced by Ischemia and Reperfusion in Gerbils by Inhibiting NLRP3 Inflammasome-Mediated Neuroinflammation

Porphyran, a sulfated polysaccharide found in various species of marine red algae, has been demonstrated to exhibit diverse bioactivities, including anti-inflammatory effects. However, the protective effects of porphyran against cerebral ischemia and reperfusion (IR) injury have not been investigated. The aim of this study was to examine the neuroprotective effects of porphyran against brain IR injury and its underlying mechanisms using a gerbil model of transient forebrain ischemia (IR in the forebrain), which results in pyramidal cell (principal neuron) loss in the cornu ammonis 1 (CA1) subregion of the hippocampus on day 4 after IR. Porphyran (25 and 50 mg/kg) was orally administered daily for one week prior to IR. Pretreatment with 50 mg/kg of porphyran, but not 25 mg/kg, significantly attenuated locomotor hyperactivity and protected pyramidal cells located in the CA1 area from IR injury. The pretreatment with 50 mg/kg of porphyran significantly suppressed the IR-induced activation and proliferation of microglia in the CA1 subregion. Additionally, the pretreatment significantly inhibited the overexpressions of nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing protein-3 (NLRP3) inflammasome complex, and pro-inflammatory cytokines (interleukin 1 beta and interleukin 18) induced by IR in the CA1 subregion. Overall, our findings suggest that porphyran exerts neuroprotective effects against brain IR injury, potentially by reducing the reaction (activation) and proliferation of microglia and reducing NLRP3 inflammasome-mediated neuroinflammation.

Human Pluripotent Stem Cell-Derived Alveolar Organoids: Cellular Heterogeneity and Maturity

Chronic respiratory diseases such as idiopathic pulmonary fibrosis, chronic obstructive pulmonary disease, and respiratory infections injure the alveoli; the damage evoked is mostly irreversible and occasionally leads to death. Achieving a detailed understanding of the pathogenesis of these fatal respiratory diseases has been hampered by limited access to human alveolar tissue and the differences between mice and humans. Thus, the development of human alveolar organoid (AO) models that mimic in vivo physiology and pathophysiology has gained tremendous attention over the last decade. In recent years, human pluripotent stem cells (hPSCs) have been successfully employed to generate several types of organoids representing different respiratory compartments, including alveolar regions. However, despite continued advances in three-dimensional culture techniques and single-cell genomics, there is still a profound need to improve the cellular heterogeneity and maturity of AOs to recapitulate the key histological and functional features of in vivo alveolar tissue. In particular, the incorporation of immune cells such as macrophages into hPSC-AO systems is crucial for disease modeling and subsequent drug screening. In this review, we summarize current methods for differentiating alveolar epithelial cells from hPSCs followed by AO generation and their applications in disease modeling, drug testing, and toxicity evaluation. In addition, we review how current hPSC-AOs closely resemble in vivo alveoli in terms of phenotype, cellular heterogeneity, and maturity.

Recombinant Human Bone Morphogenetic Protein-2 Priming of Mesenchymal Stem Cells Ameliorate Acute Lung Injury by Inducing Regulatory T Cells

Mesenchymal stromal/stem cells (MSCs) possess immunoregulatory properties and their regulatory functions represent a potential therapy for acute lung injury (ALI). However, uncertainties remain with respect to defining MSCs-derived immunomodulatory pathways. Therefore, this study aimed to investigate the mechanism underlying the enhanced effect of human recombinant bone morphogenic protein-2 (rhBMP-2) primed ES-MSCs (MSCBMP2) in promoting Tregs in ALI mice. MSC were preconditioned with 100 ng/ml rhBMP-2 for 24 h, and then administrated to mice by intravenous injection after intratracheal injection of 1 mg/kg LPS. Treating MSCs with rhBMP-2 significantly increased cellular proliferation and migration, and cytokines array reveled that cytokines release by MSCBMP2 were associated with migration and growth. MSCBMP2 ameliorated LPS induced lung injury and reduced myeloperoxidase activity and permeability in mice exposed to LPS. Levels of inducible nitric oxide synthase were decreased while levels of total glutathione and superoxide dismutase activity were further increased via inhibition of phosphorylated STAT1 in ALI mice treated with MSCBMP2. MSCBMP2 treatment increased the protein level of IDO1, indicating an increase in Treg cells, and Foxp3+CD25+ Treg of CD4+ cells were further increased in ALI mice treated with MSCBMP2. In co-culture assays with MSCs and RAW264.7 cells, the protein level of IDO1 was further induced in MSCBMP2. Additionally, cytokine release of IL-10 was enhanced while both IL-6 and TNF-α were further inhibited. In conclusion, these findings suggest that MSCBMP2 has therapeutic potential to reduce massive inflammation of respiratory diseases by promoting Treg cells.

PTD-FGF2 Attenuates Elastase Induced Emphysema in Mice and Alveolar Epithelial Cell Injury

Aberrant communication in alveolar epithelium is a major feature of inflammatory response for the airway remodeling leading to chronic obstructive pulmonary disease (COPD). In this study, we investigated the effect of protein transduction domains (PTD) conjugated Basic Fibroblast Growth Factor (FGF2) (PTD-FGF2) in response to cigarette smoke extract (CSE) in MLE-12 cells and porcine pancreatic elastase (PPE)-induced emphysematous mice. When PPE-induced mice were intraperitoneally treated with 0.1-0.5 mg/kg PTD-FGF2 or FGF2, the linear intercept, infiltration of inflammatory cells into alveoli and pro-inflammatory cytokines were significantly decreased. In western blot analysis, phosphorylated protein levels of c-Jun N-terminal Kinase 1/2 (JNK1/2), extracellular signal-regulated kinase (ERK1/2) and p38 mitogen-activated protein kinases (MAPK) were decreased in PPE-induced mice treated PTD-FGF2. In MLE-12 cells, PTD-FGF2 treatment decreased reactive oxygen species (ROS) production and further decreased Interleukin-6 (IL-6) and IL-1b cytokines in response to CSE. In addition, phosphorylated protein levels of ERK1/2, JNK1/2 and p38 MAPK were reduced. We next determined microRNA expression in the isolated exosomes of MLE-12 cells. In reverse transcription-polymerase chain reaction (RT-PCR) analysis, level of let-7c miRNA was significantly increased while levels of miR-9 and miR-155 were decreased in response to CSE. These data suggest that PTD-FGF2 treatment plays a protective role in regulation of let-7c, miR-9 and miR-155 miRNA expressions and MAPK signaling pathways in CSE-induced MLE-12 cells and PPE-induced emphysematous mice.

[Association between volatile organic compounds and mortality risk of stroke]

Objective: To investigate the effect of volatile organic compounds (VOCs) exposure in the atmosphere on the risk of daily death from stroke in Guangzhou. Methods: Daily average concentrations of twelve atmospheric VOCs, meteorological factors, and daily deaths for stroke and its subtypes (including ischemic and hemorrhagic stroke) in Guangzhou from 2020 to 2021 were collected. The time-series Poisson generalized additive model was established to analyze the relationship between daily average concentrations of atmospheric VOCs and daily mortality from a stroke on different lag days. The season, gender, and age group further performed stratification analysis. Results: Toluene and n-pentane were associated with a higher mortality risk from stroke and its subtypes. For each interquartile range (IQR) increment in toluene concentration at lag0- 1 days, the RRs for mortality from stroke and hemorrhagic stroke were 1.060 (95%CI: 1.036-1.085) and 1.071 (95%CI: 1.030-1.113), respectively. For each IQR increment in n-pentane concentration, the RR for mortality from ischemic stroke was 1.064 (95%CI: 1.030-1.099). The effect estimates of VOCs may be higher during the cold season and among women and people aged ≥75 years. For each IQR increment in toluene concentration, the RRs for mortality risk of stroke in the cold season and women were 1.099 (95%CI: 1.056-1.143) and 1.085 (95%CI: 1.050-1.120), respectively. For n-pentane, the RR for death risk of stroke in people aged ≥75 years old was 1.072 (95%CI: 1.036-1.109). Results of sensitivity analysis showed that the effect estimates fluctuated less when PM2.5 and O3 were separately introduced for the two-pollutant model, as well as changing the degrees of freedom for covariates. Conclusions: This study suggests that VOCs may be an independent risk factor for daily mortality from stroke. Moreover, Toluene presented the most significant health impact.

Cigarette Smoke-Induced Respiratory Response: Insights into Cellular Processes and Biomarkers

Cigarette smoke (CS) poses a significant risk factor for respiratory, vascular, and organ diseases owing to its high content of harmful chemicals and reactive oxygen species (ROS). These substances are known to induce oxidative stress, inflammation, apoptosis, and senescence due to their exposure to environmental pollutants and the presence of oxidative enzymes. The lung is particularly susceptible to oxidative stress. Persistent oxidative stress caused by chronic exposure to CS can lead to respiratory diseases such as chronic obstructive pulmonary disease (COPD), pulmonary fibrosis (PF), and lung cancer. Avoiding exposure to environmental pollutants, like cigarette smoke and air pollution, can help mitigate oxidative stress. A comprehensive understanding of oxidative stress and its impact on the lungs requires future research. This includes identifying strategies for preventing and treating lung diseases as well as investigating the underlying mechanisms behind oxidative stress. Thus, this review aims to investigate the cellular processes induced by CS, specifically inflammation, apoptosis, senescence, and their associated biomarkers. Furthermore, this review will delve into the alveolar response provoked by CS, emphasizing the roles of potential therapeutic target markers and strategies in inflammation and oxidative stress.

Cyclic Phytosphingosine-1-Phosphate Primed Mesenchymal Stem Cells Ameliorate LPS-Induced Acute Lung Injury in Mice

Background and Objectives

O-cyclic phytosphingosine-1-phosphate (cP1P) is a synthetic chemical and has a structure like sphingosine-1-phosphate (S1P). S1P is known to promote cell migration, invasion, proliferation, and anti-apoptosis through hippocampal signals. However, S1P mediated cellular-, molecular mechanism is still remained in the lung. Acute lung injury (ALI) and its severe form acute respiratory distress syndrome (ARDS) are characterized by excessive immune response, increased vascular permeability, alveolar-peritoneal barrier collapse, and edema. In this study, we determined whether cP1P primed human dermal derived mesenchymal stem cells (hdMSCs) ameliorate lung injury and its therapeutic pathway in ALI mice.

Methods and Results

cP1P treatment significantly stimulated MSC migration and invasion ability. In cytokine array, secretion of vascular-related factors was increased in cP1P primed hdMSCs (hdMSC^cP1P), and cP1P treatment induced inhibition of Lats while increased phosphorylation of Yap. We next determined whether hdMSC^cP1P reduce inflammatory response in LPS exposed mice. hdMSC^cP1P further decreased infiltration of macrophage and neutrophil, and release of TNF-α, IL-1β, and IL-6 were reduced rather than naïve hdMSC treatment. In addition, phosphorylation of STAT1 and expression of iNOS were significantly decreased in the lungs of MSC^cP1P treated mice.

Conclusions

Taken together, these data suggest that cP1P treatment enhances hdMSC migration in regulation of Hippo signaling and MSC^cP1P provide a therapeutic potential for ALI/ARDS treatment.

Establishment of a human induced pluripotent stem cell derived alveolar organoid for toxicity assessment

Alveolar epithelial cells (AECs) are vulnerable to injury, which can result in epithelial hyperplasia, apoptosis, and chronic inflammation. In this study, we developed human induced pluripotent stem cell (hiPS) cell-derived AECs (iAECs) and the iAECs based organoids (AOs) for testing AEC toxicity after chemical exposure. HiPS cells were cultured for 14 days with differentiation medium corresponding to each step, and the iAECs-based AOs were maintained for another 14 days. SFTPC and AQP5 were expressed in the AOs, and mRNA levels of SOX9, NKX2.1, GATA6, HOPX, and ID2 were increased. The AOs were exposed for 24 h to nine chemical substances, and IC₅₀ values of the nine chemicals were determined using MTT assay. When the correlations between iAECs 2D culture and AOs 3D culture were calculated using Pearson's correlation coefficient r value, the nine chemicals that caused a significant decrease of cell viability in 3D culture were found to be highly correlated in 2D culture. The cytotoxicity and nitric oxide release in AO cultured with macrophages were then investigated. When AOs with macrophages were exposed to sodium chromate for 24 h, the IC₅₀ value and nitric oxide production were higher than when the AOs were exposed alone. Taken together, the AO-based 3D culture system provides a useful platform for understanding biological characteristics of AECs and modeling chemical exposures.

Acute Inhibition of the Human Kv1.5 Channel by H1 Receptor Antagonist Dimenhydrinate: Mode of Action

Dimenhydrinate, an H1 receptor antagonist, is generally used for the prevention and treatment of nausea and vomiting. However, cardiac arrhythmias have been reported to be associated with the overdose of histamine H1 receptor antagonists, indicating the probable effect of antihistamines on ion channels. By using a two-microelectrode voltage clamp, we have herein studied the electrophysiological effects of dimenhydrinate on the human Kv1.5 channel in the Xenopus oocyte expression system. Dimenhydrinate acutely and reversibly suppressed the amplitudes of the peak and the steady-state current, within 6 min. The inhibitory effect of dimenhydrinate on the peak and the steady-state Kv1.5 currents increased progressively from -10 to +50 mV. At each test voltage, the drug suppressed both the peak and the steady-state currents to a similar extent. When the oocytes were stimulated at the rates of 5- and 30-s intervals, dimenhydrinate-induced a use-dependent blockade of the human Kv1.5 channel. Dimenhydrinate expedited the timecourse of the Kv1.5 channel activation more effectively than the timecourse of its inactivation. However, the activation and inactivation curves of the channel were not altered by the H1 receptor antagonist. In conclusion, we found that dimenhydrinate inhibits the human Kv1.5 channel by changing the channel's activation mode, thereby possibly increasing the possibility of triggering cardiac arrhythmias and affecting atrial fibrillation.

L-carnosine Attenuates Bleomycin-Induced Oxidative Stress via NFκB Pathway in the Pathogenesis of Pulmonary Fibrosis

Idiopathic Pulmonary fibrosis (IPF), a chronic interstitial lung disease, has pulmonary manifestations clinically characterized by collagen deposition, epithelial cell injury, and a decline in lung function. L-carnosine, a dipeptide consisting of β-alanine and L-histidine, has demonstrated a therapeutic effect on various diseases because of its pivotal function. Despite the effect of L-carnosine in experimental IPF mice, its anti-oxidative effect and associated intercellular pathway, particularly alveolar epithelial cells, remain unknown. Therefore, we demonstrated the anti-fibrotic and anti-inflammatory effects of L-carnosine via Reactive oxygen species (ROS) regulation in bleomycin (BLM)-induced IPF mice. The mice were intratracheally injected with BLM (3 mg/kg) and L-carnosine (150 mg/kg) was orally administrated for 2 weeks. BLM exposure increased the protein level of Nox2, Nox4, p53, and Caspase-3, whereas L-carnosine treatment suppressed the protein level of Nox2, Nox4, p53, and Caspase-3 cleavage in mice. In addition, the total SOD activity and mRNA level of Sod2, catalase, and Nqo1 increased in mice treated with L-carnosine. At the cellular level, a human fibroblast (MRC-5) and mouse alveolar epithelial cell (MLE-12) were exposed to TGFβ1 following L-carnosine treatment to induce fibrogenesis. Moreover, MLE-12 cells were exposed to cigarette smoke extract (CSE). Consequently, L-carnosine treatment ameliorated fibrogenesis in fibroblasts and alveolar epithelial cells, and inflammation induced by ROS and CSE exposure was ameliorated. These results were associated with the inhibition of the NFκB pathway. Collectively, our data indicate that L-carnosine induces anti-inflammatory and anti-fibrotic effects on alveolar epithelial cells against the pathogenesis of IPF.

[Research progress in association between endothelial dysfunction and periodontitis]

Vascular endothelium formulates the basic defense against cardiovascular diseases. Multiple factors such as inflammatory factors, oxidative stress and biological factors can cause endothelial dysfunction and be involved in the formation and development of cardiovascular diseases. In studies of recent years, accumulated evidences showed that periodontitis was an independent risk factor for cardiovascular events, and was related to vascular endothelial dysfunction. Periodontal therapy could improve the vascular endothelial function. In this paper, the epidemiological evidences of associations between periodontitis and vascular endothelial dysfunction in recent years were listed, and the possible mechanisms of periodontitis aggravating endothelial dysfunction were analyzed. The importance of periodontal intervention in improving endothelial function was emphasized. This will provide new ideas for further study about the relationship between periodontitis and cardiovascular diseases and for the prevention and treatment strategies.

Human pluripotent stem cell-derived macrophages and macrophage-derived exosomes: therapeutic potential in pulmonary fibrosis

Pulmonary fibrosis (PF) is a fatal chronic disease characterized by accumulation of extracellular matrix and thickening of the alveolar wall, ultimately leading to respiratory failure. PF is thought to be initiated by the dysfunction and aberrant activation of a variety of cell types in the lung. In particular, several studies have demonstrated that macrophages play a pivotal role in the development and progression of PF through secretion of inflammatory cytokines, growth factors, and chemokines, suggesting that they could be an alternative therapeutic source as well as therapeutic target for PF. In this review, we describe the characteristics, functions, and origins of subsets of macrophages involved in PF and summarize current data on the generation and therapeutic application of macrophages derived from pluripotent stem cells for the treatment of fibrotic diseases. Additionally, we discuss the use of macrophage-derived exosomes to repair fibrotic lung tissue.

ESMO expert consensus statements on the management of EGFR mutant non-small-cell lung cancer

The European Society for Medical Oncology (ESMO) held a virtual consensus-building process on epidermal growth factor receptor (EGFR)-mutant non-small-cell lung cancer in 2021. The consensus included a multidisciplinary panel of 34 leading experts in the management of lung cancer. The aim of the consensus was to develop recommendations on topics that are not covered in detail in the current ESMO Clinical Practice Guideline and where the available evidence is either limited or conflicting. The main topics identified for discussion were: (i) tissue and biomarkers analyses; (ii) early and locally advanced disease; (iii) metastatic disease and (iv) clinical trial design, patient's perspective and miscellaneous. The expert panel was divided into four working groups to address questions relating to one of the four topics outlined above. Relevant scientific literature was reviewed in advance. Recommendations were developed by the working groups and then presented to the entire panel for further discussion and amendment before voting. This manuscript presents the recommendations developed, including findings from the expert panel discussions, consensus recommendations and a summary of evidence supporting each recommendation.

Reduced receptor for advanced glycation end products is associated with α-SMA expression in patients with idiopathic pulmonary fibrosis and mice

Background

Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive interstitial lung disease. Despite alveolar epithelial cells is crucial role in lung, its contribution and the associated biomarker remain unknown in the pathogenesis of IPF. Recently, environmental factors including stone dust, silica and cigarette smoking were found as risk factors involved in IPF. Receptor for advanced glycation end products (RAGE) is a member of the immunoglobulin super family of cell surface receptors. It has been shown that interaction between RAGE and its ligands on immune cells mediates cellular migration and regulation of pro-inflammation. RAGE is highly expressed in the lung, in particular, alveolar epithelial cells. Therefore, we determined whether RAGE expression is associated with fibrosis-associated genes in patients with IPF and mice.

Results

When bleomycin (BLM) was intratracheally administered to C57BL/6 mice for 1, 2 weeks, macrophage and neutrophils were significantly increased. The fibrotic nodule formed and accumulation of collagen was determined after BLM injection in H&E- and Masson’s trichrome staining. Levels of elastin, Col1a1 and fibronectin were increased in quantitative real-time PCR and protein levels of α-SMA was increased in western blot analysis. In the lung tissues of 1 mg/kg BLM-induced mice, RAGE expression was gradually decreased in 1- and 2 weeks in immunohistochemistry and western blot analysis, and 3 mg/kg of BLM-induced mice exhibited decreased RAGE levels while α-SMA expression was increased. We next determined RAGE expression in the lungs of IPF patients using immunohistochemistry. As a result, RAGE expression was decreased, while α-SMA expression was increased compared with non-IPF subjects.

Conclusions

Our findings suggest that reduced RAGE was associated with increased fibrotic genes in BLM-induced mice and patients with IPF. Therefore, RAGE could be applied with a biomarker for prognosis and diagnosis in the pathogenesis of IPF.

Organoid Model in Idiopathic Pulmonary Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive- fibrosing disease characterized by extensive deposition of extracellular matrix (ECM), scarring of the lung parenchyma. Despite increased awareness of IPF, etiology and physiological mechanism of IPF are unclear. Therefore, preclinical model will require relevant and recapitulative features of IPF. Recently, pluripotent stem cells (PSC)-based organoid studies are emerging as an alternative approach able to recapitulate tissue architecture with remarkable fidelity. Moreover, these biomimetic tissue models can be served to investigate the mechanisms of diverse disease progression. In this review, we will overview the current organoids technology for human disease modeling including lung organoids for IPF.

Suppression of voltage-gated K+ channels by darifenacin in coronary arterial smooth muscle cells

Darifenacin, an anticholinergic agent, has been used to treat overactive bladder syndrome. Despite its extensive clinical use, there is little information about the effect of darifenacin on vascular ion channels, specifically K⁺ channels. This study aimed to investigate the effect of the anti-muscarinic drug darifenacin on voltage-gated K⁺ (Kv) channels, vascular contractility, and coronary blood flow in rabbit coronary arteries. We used the whole-cell patch-clamp technique to evaluate the effect of darifenacin on Kv channels. Darifenacin inhibited the Kv current in a concentration-dependent manner. Applying 1 μM darifenacin shifted the activation and inactivation curves toward a more positive and negative potential, respectively. Darifenacin slowed the time constants of recovery from inactivation. Furthermore, blockade of the Kv current with darifenacin was increased gradually by applying a train of pulses, indicating that darifenacin inhibited Kv currents in a use- (state)-dependent manner. The darifenacin-mediated inhibition of Kv currents was associated with the Kv1.5 subtype, not the Kv2.1 or Kv7 subtype. Applying another anti-muscarinic drug atropine or ipratropium did not affect the Kv current or change the inhibitory effect of darifenacin. Isometric organ bath experiments using isolated coronary arteries were applied to evaluate whether darifenacin-induced inhibition of the Kv channel causes vasocontraction. Darifenacin substantially induced vasocontraction. Furthermore, darifenacin caused membrane depolarization and decreased coronary blood flow. From these results, we concluded that darifenacin inhibits the Kv currents in concentration- and use- (state)-dependent manners. Inhibition of the Kv current with darifenacin occurred by shifting the steady-state activation and inactivation curves regardless of its anti-muscarinic effect.

WKYMVm ameliorates acute lung injury via neutrophil antimicrobial peptide derived STAT1/IRF1 pathway

Formyl peptide receptors (FPRs) are mainly expressed on leucocytes and sense microbe-associated molecular pattern (MAMP) molecules, thereby regulating leukocyte chemotaxis and activation. The formyl peptide receptor 2 (FPR2) selective agonist WKYMVm (Trp-Lys-Met-Val-D-Met) has shown potent pro-angiogenic, anti-inflammatory, and anti-apoptotic properties. In this study, we investigated whether WKYMVm exhibits bactericidal activity during neutrophil accumulation in acute lung injury (ALI) in mice and determined its cellular signaling pathways in HL-60 neutrophil-like cells. A daily intraperitoneal treatment of ALI mice with WKYMVm (2.5- and 5 mg/kg/d) daily over four days decreased the levels of proinflammatory cytokines TNF-α, IL-6, and IL-1β, while it increased the MPO and NO release by differentiated HL-60 neutrophil-like cells. The IRF1 level and STAT1 phosphorylation at S727 were increased in the lungs of mice with ALI treated with WKYMVm. Lung histology induced by ALI was unaffected by treatment with WKYMVm. In vitro, WKYMVm increased MPO, NO, and SOD activity, as well as IRF1 and STAT1 phosphorylation at Ser727. Taken together, our data suggest therapeutic potential of WKYMVm, via FPR2-dependent regulation of STAT1/IRF1, in ALI.

Empagliflozin dilates the rabbit aorta by activating PKG and voltage-dependent K+ channels

We investigated the vasodilatory effects of empagliflozin (a sodium-glucose co-transporter 2 inhibitor) and the underlying mechanisms using rabbit aorta. Empagliflozin induced vasodilation in a concentration-dependent manner independently of the endothelium. Likewise, pretreatment with the nitric oxide synthase inhibitor L-NAME or the SKca inhibitor apamin together with the IKca inhibitor TRAM-34 did not impact the vasodilatory effects of empagliflozin. Pretreatment with the adenylyl cyclase inhibitor SQ22536 or a guanylyl cyclase inhibitor ODQ or a protein kinase A (PKA) inhibitor KT5720 also did not alter the vasodilatory response of empagliflozin. However, the vasodilatory effects of empagliflozin were significantly reduced by pretreatment with the protein kinase G (PKG) inhibitor KT5823. Although application of the ATP-sensitive K⁺ (K_ATP) channel inhibitor glibenclamide, large-conductance Ca²⁺-activated K⁺ (BK_Ca) channel inhibitor paxilline, or inwardly rectifying K⁺ (Kir) channel inhibitor Ba²⁺ did not impact the vasodilatory effects of empagliflozin, pretreatment with the voltage-dependent K⁺ (Kv) channel inhibitor 4-AP reduced the vasodilatory effects of empagliflozin. Pretreatment with DPO-1 (Kv1.5 channel inhibitor), guangxitoxin (Kv2.1 channel inhibitor), or linopirdine (Kv7 channel inhibitor) had little effect on empagliflozin-induced vasodilation. Application of nifedipine (L-type Ca²⁺ channel inhibitor) or thapsigargin (sarco-endoplasmic reticulum Ca²⁺-ATPase pump inhibitor) did not impact empagliflozin-induced vasodilation. Therefore, empagliflozin induces vasodilation by activating PKG and Kv channels.

Inhibition of voltage-dependent K+ channels by iloperidone in coronary arterial smooth muscle cells

Iloperidone, a second-generation atypical antipsychotic drug, is widely used in the treatment of schizophrenia. However, the side-effects of iloperidone on vascular K⁺ channels remain to be determined. Therefore, we explored the effect of iloperidone on voltage-dependent K⁺ (Kv) channels in rabbit coronary arterial smooth muscle cells using the whole-cell patch-clamp technique. Iloperidone inhibited vascular Kv channels in a concentration-dependent manner with a half-maximal inhibitory concentration (IC₅₀ ) of 2.11 ± 0.5 μM and a Hill coefficient of 0.68 ± 0.03. Iloperidone had no effect on the steady-state inactivation kinetics. However, it shifted the steady-state activation curve to the right, indicating that iloperidone inhibited Kv channels by influencing the voltage sensors. Application of 20 repetitive depolarizing pulses (1 and 2 Hz) progressively increased the inhibition of the Kv current in the presence of iloperidone. Furthermore, iloperidone increased the recovery time constant from Kv channel inactivation, suggesting that iloperidone-induced inhibition of Kv channels is use (state)-dependent. Pretreatment with a Kv1.5 inhibitor (diphenyl phosphine oxide 1 [DPO-1]) inhibited the Kv current to a level similar to that with iloperidone alone. However, pretreatment with a Kv2.1 or Kv7.X inhibitor (guangxitoxin or linopirdine) did not affect the inhibitory effect of iloperidone on Kv channels. Therefore, iloperidone directly inhibits Kv channels in a concentration- and use (state)-dependent manner independently of its antagonism of serotonin and dopamine receptors. Furthermore, the primary target of iloperidone is the Kv1.5 subtype.

Perivascular Stem Cells Suppress Inflammasome Activation during Inflammatory Responses in Macrophages

Background and Objectives

Perivascular stem cells (PVCs) have been identified as precursors of mesenchymal stem cells (MSCs) that offer promising prospects for application in the development of cellular therapies. Although PVCs have been demonstrated to have greater therapeutic potential compared to bone marrow and adipose tissue-derived MSCs in various diseases, the regulatory role of PVCs on inflammasome activation during macrophage-mediated inflammatory responses has not been investigated.

Methods and Results

In this study, we found that the PVC secretome effectively alleviates secretion of both caspase-1 and interleukin-1β in lipopolysaccharide-primed and activated human and murine macrophages by blocking inflammasome activation and attenuating the production of mitochondrial reactive oxygen species (ROS). We further showed that the PVC secretome significantly reduces inflammatory responses and endoplasmic reticulum stress in peritoneal macrophages in a mouse model of monosodium urate-induced peritonitis. A cytokine antibody array analysis revealed that the PVC secretome contains high levels of serpin E1 and angiogenin, which may be responsible for the inhibitory effects on mitochondrial ROS generation as well as on inflammasome activation.

Conclusions

Our results suggest that PVCs may be therapeutically useful for the treatment of macrophage- and inflammation-mediated diseases by paracrine action via the secretion of various biological factors.

Mesenchymal Stem Cell Transplantation Promotes Functional Recovery through MMP2/STAT3 Related Astrogliosis after Spinal Cord Injury

Background and Objectives

Treatment with mesenchymal stem cells (MSC) in spinal cord injury (SCI) has been highlighted as therapeutic candidate for SCI. Although astrogliosis is a major phenomenon after SCI, the role of astrogliosis is still controversial. In this study, we determined whether acute transplantation of MSC improves the outcome of SCI through modulating astrogliosis.

Methods

Bone marrow derived rat MSCs were induced neural differentiation and transplanted after acute SCI rats. Matrix metalloproteinase (MMP) and neuro-inflammatory pathway were analyzed for acute astrogliosis at 1, 3 and 7 d after SCI in RT-PCR- and western blot analysis. Functional outcome was assessed serially at postoperative 1 d and weekly for 4 weeks. Histopathologic analysis was undertaken at 7 and 28 d following injury in immunohistochemistry.

Results

Transplantation of MSCs decreased IL-1α, CXCL-2, CXCL-10, TNF-α and TGF-β in a rat model of contusive SCI. Protein level of NF-κB p65 was slightly decreased while level of STAT-3 was increased. In immunohistochemistry, MSC transplantation increased acute astrogliosis whereas attenuated scar formation with increased sparing white matter of spinal cord lesions. In RT-PCR analysis, mRNA levels of MMP2 was significantly increased in MSC transplanted rats. In BBB locomotor scale, the rats of MSC treated group exhibited improvement of functional recovery.

Conclusions

Transplantation of MSC reduces the inflammatory reaction and modulates astrogliosis via MMP2/STAT3 pathway leading to improve functional recovery after SCI in rats.

Anti-proliferative Effect of a Novel Anti-oxidative Peptide in Hanwoo Beef on Human Colorectal Carcinoma Cells

The present study aimed to characterise anti-oxidant peptides from water-soluble protein extracts of Hanwoo beef and evaluate their anti-proliferative effect on human colorectal carcinoma cells (HCT116). Antioxidant peptides were purified from the low-molecular-weight fraction (<3 kDa) of Hanwoo beef extract. Antioxidant activity of peptide fractions was determined using the oxygen radical absorbance capacity (ORAC) assay. Purified peptide (P3) displayed higher ORAC activity than the low-molecular-weight fraction (202.66 μM TE/g vs 167.38 μM TE/g of dry matter, respectively) (p<0.05). The peptide sequence of P3 was Cys-Cys-Cys-Cys-Ser-Val-Gln-Lys (888.30 Da). The novel peptide P3, at 250 μg/mL, also significantly inhibited HCT116 cell proliferation up to 25.24% through phosphorylation of ERK, JNK, and p38 kinase (p<0.05). Hence, antioxidant peptide P3 from Hanwoo beef extract can be used as an antioxidative and anti-cancer agent in the functional food industry.

Inhibition of MicroRNA-221 and 222 Enhances Hematopoietic Differentiation from Human Pluripotent Stem Cells via c-KIT Upregulation

The stem cell factor (SCF)/c-KIT axis plays an important role in the hematopoietic differentiation of human pluripotent stem cells (hPSCs), but its regulatory mechanisms involving microRNAs (miRs) are not fully elucidated. Here, we demonstrated that supplementation with SCF increases the hematopoietic differentiation of hPSCs via the interaction with its receptor tyrosine kinase c-KIT, which is modulated by miR-221 and miR-222. c-KIT is comparably expressed in undifferentiated human embryonic and induced pluripotent stem cells. The inhibition of SCF signaling via treatment with a c-KIT antagonist (imatinib) during hPSC-derived hematopoiesis resulted in reductions in the yield and multi-lineage potential of hematopoietic progenitors. We found that the transcript levels of miR-221 and miR-222 targeting c-KIT were significantly lower in the pluripotent state than they were in terminally differentiated somatic cells. Furthermore, suppression of miR-221 and miR-222 in undifferentiated hPSC cultures induced more hematopoiesis by increasing c-KIT expression. Collectively, our data implied that the modulation of c-KIT by miRs may provide further potential strategies to expedite the generation of functional blood cells for therapeutic approaches and the study of the cellular machinery related to hematologic malignant diseases such as leukemia.

High-quality thulium iron garnet films with tunable perpendicular magnetic anisotropy by off-axis sputtering - correlation between magnetic properties and film strain

Thulium iron garnet (TmIG) films with perpendicular magnetic anisotropy (PMA) were grown on gadolinium gallium garnet (GGG) (111) substrates by off-axis sputtering. High-resolution synchrotron radiation X-ray diffraction studies and spherical aberration-corrected scanning transmission electron microscope (Cs-corrected STEM) images showed the excellent crystallinity of the films and their sharp interface with GGG. Damping constant of TmIG thin film was determined to be 0.0133 by frequency-dependent ferromagnetic resonance (FMR) measurements. The saturation magnetization (Ms) and the coercive field (Hc) were obtained systematically as a function of the longitudinal distance (L) between the sputtering target and the substrate. A 170% enhancement of PMA field (H⊥) was achieved by tuning the film composition to increase the tensile strain. Moreover, current-induced magnetization switching on a Pt/TmIG structure was demonstrated with an ultra-low critical current density (jc) of 2.5 × 106 A/cm2, an order of magnitude smaller than the previously reported value. We were able to tune Ms, Hc and H⊥ to obtain an ultra-low jc of switching the magnetization, showing the great potential of sputtered TmIG films for spintronics.

Inhibition of RAGE Attenuates Cigarette Smoke-Induced Lung Epithelial Cell Damage via RAGE-Mediated Nrf2/DAMP Signaling

The oxidative stress and cellular apoptosis by environmental factor including cigarette smoke induces alveolar airway remodeling leading to chronic obstructive pulmonary disease (COPD). Recently, the receptor for advanced glycan end products (RAGE) which is highly expressed in alveolar epithelium is emerging as a biomarker for COPD susceptibility or progression. However, it still remains unknown how RAGE plays a role in cigarette smoke extract (CSE)-exposed human alveolar type II epithelial cell line. Therefore, we determined the efficacy of RAGE-specific antagonist FPS-ZM1 in response to CSE-induced lung epithelial cells. CSE induced the elevated generation of RONS and release of pro-inflammatory cytokines, and impaired the cellular antioxidant defense system. Further, CSE induced the alteration of RAGE distribution via the activation of redox-sensitive DAMP (Damage-associated molecular patterns) signaling through Nrf2 in cells. Although pre-treatment with SB202190 (p38 inhibitor) or SP600125 (JNK inhibitor) failed to recover the alteration of RAGE distribution, treatment of FPS-ZM1 significantly exhibited anti-inflammatory and anti-oxidative/nitrosative effects, also inhibited the activation of redox-sensitive DAMP signaling through Nrf2 (nuclear factor erythroid 2-related factor 2) migration in the presence of CSE. Taken together, our data demonstrate that RAGE and Nrf2 play a pivotal role in maintenance of alveolar epithelial integrity.

Early IV-injected human dermis-derived mesenchymal stem cells after transient global cerebral ischemia do not pass through damaged blood-brain barrier

There is lack of researches on effects of intravenously injected mesenchymal stem cells (MSCs) against transient cerebral ischemia (TCI). We investigated the disruption of the neurovascular unit (NVU), which comprises the blood-brain barrier and examined entry of human dermis-derived MSCs (hDMSCs) into the damaged hippocampal CA1 area in a gerbil model of TCI and their subsequent effects on neuroprotection and cognitive function. Impairments of neurons and blood-brain barrier were examined by immunohistochemistry, electron microscopy, and Evans blue and immunoglobulin G leakage. Neuronal death was observed in pyramidal neurons 5-day postischemia. NVU were structurally damaged; in particular, astrocyte end-feet were severely damaged from 2-day post-TCI and immunoglobulin G leaked out of the CA1 area 2 days after 5 min of TCI; however, Evans blue extravasation was not observed. On the basis of the results of NVU damages, ischemic gerbils received PKH2-transfected hDMSCs 3 times at early times (3 hr, 2, and 5 days) after TCI, and fluorescence imaging was used to detect hDMSCs in the tissue. PKH2-transfected hDMSCs were not found in the CA1 from immediate time to 8 days after injection, although they were detected in the liver. Furthermore, hDMSCs transplantation did not protect CA1 pyramidal neurons and did not improve cognitive impairment. Intravenously transplanted hDMSCs did not migrate to the damaged CA1 area induced by TCI. These findings suggest no neuroprotection and cognitive improvement by intravenous hDMSCs transplantation after 5 min of TCI.

Biocompatibility and hemocompatibility of efficiently decellularized whole porcine kidney for tissue engineering

Whole kidney decellularization is a promising approach in regenerative medicine for engineering a functional organ. The reaction of the potential host depends on the biocompatibility of these decellularized constructs. Despite the proven ability of decellularized kidney scaffolds to guide cell attachment and growth, little is known about biocompatibility and hemocompatibility of these scaffolds. Our aim is to prepare decellularized kidneys of a clinically relevant size and evaluate its biocompatibility and hemocompatibility. Porcine kidneys were cannulated via the renal artery, and then perfused with 0.1% sodium dodecyl sulfate solution. Hematoxylin and eosin as well as DAPI staining confirmed cellular clearance from native kidneys in addition to preservation of the microstructure. SEM confirmed the absence of any cellular content within the scaffold, which is maintained in a well-organized 3D architecture. Decellularized kidneys retained the intact renal vasculature upon examination with contrast radiography. The essential structural extracellular matrix molecules were well-preserved. Scaffolds were susceptible to enzymatic degradation upon collagenase treatment. Scaffolds showed a good hemocompatibility when exposed to porcine blood. Decellularization was efficient to remove 97.7% of DNA from native kidneys in addition to the immunogenic and pathogenic antigens. Scaffolds did not induce the human immune response in vitro. Decellularized kidneys were non-cytotoxic to pig kidney cells (PKs). PKs were able to grow and proliferate within the decellularized renal scaffolds with maintaining a higher function than cells grown as monolayers. Thus, we have developed a rapid decellularization technique for generating biocompatible kidney scaffolds that represents a step toward development of a transplantable organ. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 2034-2047, 2018.

A novel endogenous damage signal, glycyl tRNA synthetase, activates multiple beneficial functions of mesenchymal stem cells

During tissue repair, the injury site releases various bioactive molecules as damage signals to actively recruit stem cells to the damaged region. Despite convincing evidence that mesenchymal stem cells (MSCs) can sense damage signals and promote repair processes, the identity of these signals and how these signals regulate stem cell-mediated tissue repair remain unknown. Glycyl tRNA synthetase (GRS) is a ubiquitously expressed enzyme that catalyzes the first step of protein synthesis in all organisms. In addition to this canonical function, we identified for the first time that GRS is released by damaged tissues or cells in response to various injury signals and may function as a damage signal that activates the proliferative, differentiation, and migratory potential of MSCs, possibly through its identified receptor, cadherin-6 (CDH-6). Binding between GRS and CDH-6 activates survival signals, such as those of the PI3K/Akt and/or FAK/ERK1/2 pathways. More importantly, we also found that MSCs stimulated with GRS show significantly improved homing and differentiation potential and subsequent in vivo therapeutic effects, in a liver fibrosis animal model. Collectively, our findings provide compelling evidence for a novel function of GRS in enhancing the multiple beneficial functions of stem cells via a non-canonical mechanism as a damage signal.

[Molecular typing characterization of food-borne methicillin-resistant Staphylococcus aureus in China]

Objective: To analyses the antimicrobial resistance and molecular characterization of 21 MRSA isolates cultured from retail foods from different provinces in China, and evaluate the molecular typing methods. Methods: Twenty-one MRSA isolates were obtained from national foodborne pathogen surveillance network in 2012 (Chinese salad, n=3; milk, n=1; cake, n=2; rice, n=1; cold noodle, n=1; spiced beef, n=1; dumpling, n=1; packed meal, n=1; salad, n=1; raw pork, n=9). The antimicrobial resistance of 21 strains to 12 antimicrobial agents was tested by broth dilution method. Polymerase chain reaction (PCR) and DNA sequencing were performed to obtain the genetic types of MLST (ST) and spa typing. The clonal complex (CC) was assigned by eBURST soft and the MLVA type (MT) and MLVA complex (MC) were identified via the database of the MLVA website (http://www.mlva.net). SmaI pulsed-field gel electrophoresis (SmaⅠ-PFGE) was also carried out to obtain the PFGE patterns of 21 strains. The genetic diversity and discriminatory power of typing were calculated by the Simpson's index of diversity (diversity index, DI) to find out the best genotyping method for MRSA. Results: All MRSA isolates showed multi-drug resistance(MDR), and were resistant to oxacillin, benzylpenicillin, clindamycin and erythromycin, and 71.4% (15/21), 47.6% (10/21), 42.9% (9/21) and 28.6% (6/21) of the MRSA isolates were resistant to tetracycline, ciprofloxacin, trimethoprim/sulfamethoxazole and gentamicin, respectively. Moreover, one strain was found to be resistant to all three antimicrobials of levofloxacin, moxifloxacin and rifampicin. Great diversity was found in these food-associated MRSA (6 STs, 7 spa types, and 9 MTs). PFGE patterns were more diverse than those of other three molecular typing methods (19 pulse types). The index of diversity (DI) of PFGE, MLVA, spa typing and MLST was 0.99, 0.80, 0.73, and 0.61, respectively. Among the MRSA isolates, CC9-ST9-t899-MT929-MC2236 (PFGE Cluster Ⅴ) was the most prevalent clone, which were all cultured from raw pork (9 isolates). Besides, two MRSA were identified as CC59-ST338-t437-MT621-MC621 (PFGE Cluster Ⅳ). Different clone had their own resistance spectrum profiles. Conclusion: The food-borne MRSA isolates were all MDR in this study. Different clones had their own resistance spectrum profiles. MLVA represented a promising tool for molecular epidemiology tracing of MRSA in foodborne disease events.

The tri-peptide GHK-Cu complex ameliorates lipopolysaccharide-induced acute lung injury in mice

The tripeptide-copper complex glycyl-l-histidyl-l-lysine-Cu (II) (GHK-Cu) is involved in wound healing and tissue remodeling. Although GHK-Cu exhibits anti-aging and tissue renewing properties, its roles in acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) are still unknown. Therefore, we examined the effects of GHK-Cu in lipopolysaccharide (LPS)-induced RAW 264.7 macrophages in vitro and ALI in mice in vivo. GHK-Cu treatment reduced reactive oxygen species (ROS) production, increased superoxide dismutase (SOD) activity while decreased TNF-α and IL-6 production through the suppression of NF-κB p65 and p38 MAPK signaling in vitro and in vivo model of ALI. Moreover, GHK-Cu attenuated LPS-induced lung histological alterations, suppressed the infiltration of inflammatory cells into the lung parenchyma in LPS-induced ALI in mice. Taken together, these findings demonstrate that GHK-Cu possesses a protective effect in LPS-induced ALI by inhibiting excessive inflammatory responses; accordingly it may represent a novel therapeutic approach for ALI/ARDS.

Strongly exchange-coupled and surface-state-modulated magnetization dynamics in Bi2Se3/yttrium iron garnet heterostructures

Harnessing the spin–momentum locking of topological surface states in conjunction with magnetic materials is the first step to realize novel topological insulator-based devices. Here, we report strong interfacial coupling in Bi₂Se₃/yttrium iron garnet (YIG) bilayers manifested as large interfacial in-plane magnetic anisotropy (IMA) and enhancement of damping probed by ferromagnetic resonance. The interfacial IMA and damping enhancement reaches a maximum when the Bi₂Se₃ film approaches its two-dimensional limit, indicating that topological surface states play an important role in the magnetization dynamics of YIG. Temperature-dependent ferromagnetic resonance of Bi₂Se₃/YIG reveals signatures of the magnetic proximity effect of T_C as high as 180 K, an emerging low-temperature perpendicular magnetic anisotropy competing the high-temperature IMA, and an increasing exchange effective field of YIG steadily increasing toward low temperature. Our study sheds light on the effects of topological insulators on magnetization dynamics, essential for the development of topological insulator-based spintronic devices.

Understanding the effects of topological insulators on magnetization dynamics of adjacent magnetic materials is essential for novel spintronic devices. Here, Fanchiang et al. report thickness dependence of interfacial in-plane magnetic anisotropy and damping enhancement in Bi₂Se₃/yttrium iron garnet (YIG) bilayers, indicating an important role of topological surface states in the magnetization dynamics of YIG.

Zinc Oxide Nanoparticles Exhibit Both Cyclooxygenase- and Lipoxygenase-Mediated Apoptosis in Human Bone Marrow-Derived Mesenchymal Stem Cells

Nanoparticles (NPs) have been recognized as both useful tools and potentially toxic materials in various industrial and medicinal fields. Previously, we found that zinc oxide (ZnO) NPs that are neurotoxic to human dopaminergic neuroblastoma SH-SY5Y cells are mediated by lipoxygenase (LOX), not cyclooxygenase-2 (COX-2). Here, we examined whether human bone marrow-derived mesenchymal stem cells (MSCs), which are different from neuroblastoma cells, might exhibit COX-2- and/or LOX-dependent cytotoxicity of ZnO NPs. Additionally, changes in annexin V expression, caspase-3/7 activity, and mitochondrial membrane potential (MMP) induced by ZnO NPs and ZnO were compared at 12 hr and 24 hr after exposure using flow cytometry. Cytotoxicity was measured based on lactate dehydrogenase activity and confirmed by trypan blue staining. Rescue studies were executed using zinc or iron chelators. ZnO NPs and ZnO showed similar dose-dependent and significant cytotoxic effects at concentrations ≥ 15 μg/mL, in accordance with annexin V expression, caspase-3/7 activity, and MMP results. Human MSCs exhibited both COX-2 and LOX-mediated cytotoxicity after exposure to ZnO NPs, which was different from human neuroblastoma cells. Zinc and iron chelators significantly attenuated ZnO NPs-induced toxicity. Conclusively, these results suggest that ZnO NPs exhibit both COX-2- and LOX-mediated apoptosis by the participation of mitochondrial dysfunction in human MSC cultures.

Cadmium-induced ER stress and inflammation are mediated through C/EBP-DDIT3 signaling in human bronchial epithelial cells

Cadmium (Cd), a major component of cigarette smoke, disrupts the normal functions of airway cells and can lead to the development of various pulmonary diseases such as chronic obstructive pulmonary disease (COPD). However, the molecular mechanisms involved in Cd-induced pulmonary diseases are poorly understood. Here, we identified a cluster of genes that are altered in response to Cd exposure in human bronchial epithelial cells (BEAS-2B) and demonstrated that Cd-induced ER stress and inflammation are mediated via CCAAT-enhancer-binding proteins (C/EBP)-DNA-damaged-inducible transcript 3 (DDIT3) signaling in BEAS-2B cells. Cd treatment led to marked upregulation and downregulation of genes associated with the cell cycle, apoptosis, oxidative stress and inflammation as well as various signal transduction pathways. Gene set enrichment analysis revealed that Cd treatment stimulated the C/EBP signaling pathway and induced transcriptional activation of its downstream target genes, including DDIT3. Suppression of DDIT3 expression using specific small interfering RNA effectively alleviated Cd-induced ER stress and inflammatory responses in both BEAS-2B and normal primary normal human bronchial epithelial cells. Taken together, these data suggest that C/EBP signaling may have a pivotal role in the early induction of ER stress and inflammatory responses by Cd exposure and could be a molecular target for Cd-induced pulmonary disease.

Gestational Diabetes Affects the Growth and Functions of Perivascular Stem Cells

Gestational diabetes mellitus (GDM), one of the common metabolic disorders of pregnancy, leads to functional alterations in various cells including stem cells as well as some abnormalities in fetal development. Perivascular stem cells (PVCs) have gained more attention in recent years, for the treatment of various diseases. However, the effect of GDM on PVC function has not been investigated. In our study, we isolated PVCs from umbilical cord of normal pregnant women and GDM patients and compared their phenotypes and function. There is no significant difference in phenotypic expression, response to bFGF exposure and adipogenic differentiation capacity between normal (N)-PVCs and GDM-PVCs. However, when compared with N-PVCs, early passage GDM-PVCs displayed decreased initial rates of cell yield and proliferation as well as a reduced ability to promote wound closure. These results suggest that maternal metabolic dysregulation during gestation can alter the function of endogenous multipotent stem cells, which may impact their therapeutic effectiveness.

Alterations of voltage-dependent K(+) channels in the mesenteric artery during the early and chronic phases of diabetes

This study investigated the alteration of voltage-dependent K(+) (Kv) channels in mesenteric arterial smooth muscle cells from control (Long-Evans Tokushima Otsuka [LETO]) and diabetic (Otsuka Long-Evans Tokushima Fatty [OLETF]) rats during the early and chronic phases of diabetes. We demonstrated alterations in the mesenteric Kv channels during the early and chronic phase of diabetes using the patch-clamp technique, the arterial tone measurement system, and RT-PCR in Long-Evans Tokushima (LETO; for control) and Otsuka Long-Evans Tokushima Fatty (OLETF; for diabetes) type 2 diabetic model rats. In the early phase of diabetes, the amplitude of mesenteric Kv currents induced by depolarizing pulses was greater in OLETF rats than in LETO rats. The contractile response of the mesenteric artery induced by the Kv inhibitor, 4-aminopyridine (4-AP), was also greater in OLETF rats. The expression of most Kv subtypes- including Kv1.1, Kv1.2, Kv1.4, Kv1.5, Kv1.6, Kv2.1, Kv3.2, Kv4.1, Kv4.3, Kv5.1, Kv6.2, Kv8.1, Kv9.3, and Kv10.1-were increased in mesenteric arterial smooth muscle from OLETF rats compared with LETO rats. However, in the chronic phase of diabetes, the Kv current amplitude did not differ between LETO and OLETF rats. In addition, the 4-AP-induced contractile response of the mesenteric artery and the expression of Kv subtypes did not differ between the two groups. The increased Kv current amplitude and Kv channel-related contractile response were attributable to the increase in Kv channel expression during the early phase of diabetes. The increased Kv current amplitude and Kv channel-related contractile response were reversed during the chronic phase of diabetes.

Paracrine influence of human perivascular cells on the proliferation of adenocarcinoma alveolar epithelial cells

Understanding the crosstalk mechanisms between perivascular cells (PVCs) and cancer cells might be beneficial in preventing cancer development and metastasis. In this study, we investigated the paracrine influence of PVCs derived from human umbilical cords on the proliferation of lung adenocarcinoma epithelial cells (A549) and erythroleukemia cells (TF-1α and K562) in vitro using Transwell® co-culture systems. PVCs promoted the proliferation of A549 cells without inducing morphological changes, but had no effect on the proliferation of TF-1α and K562 cells. To identify the factors secreted from PVCs, conditioned media harvested from PVC cultures were analyzed by antibody arrays. We identified a set of cytokines, including persephin (PSPN), a neurotrophic factor, and a key regulator of oral squamous cell carcinoma progression. Supplementation with PSPN significantly increased the proliferation of A549 cells. These results suggested that PVCs produced a differential effect on the proliferation of cancer cells in a cell-type dependent manner. Further, secretome analyses of PVCs and the elucidation of the molecular mechanisms could facilitate the discovery of therapeutic target(s) for lung cancer.

Blockade of RAGE ameliorates elastase-induced emphysema development and progression via RAGE-DAMP signaling

The receptor for advanced glycan end products (RAGE) has been identified as a susceptibility gene for chronic obstructive pulmonary disease (COPD) in genome-wide association studies (GWASs). However, less is known about how RAGE is involved in the pathogenesis of COPD. To determine the molecular mechanism by which RAGE influences COPD in experimental COPD models, we investigated the efficacy of the RAGE-specific antagonist FPS-ZM1 administration in in vivo and in vitro COPD models. We injected elastase intratracheally and the RAGE antagonist FPS-ZM1 in mice, and the infiltrated inflammatory cells and cytokines were assessed by ELISA. Cellular expression of RAGE was determined in protein, serum, and bronchoalveolar lavage fluid of mice and lungs and serum of human donors and patients with COPD. Downstream damage-associated molecular pattern (DAMP) pathway activation in vivo and in vitro and in patients with COPD was assessed by immunofluorescence staining, Western blot analysis, and ELISA. The expression of membrane RAGE in initiating the inflammatory response and of soluble RAGE acting as a decoy were associated with up-regulation of the DAMP-related signaling pathway via Nrf2. FPS-ZM1 administration significantly reversed emphysema in the lung of mice. Moreover, FPS-ZM1 treatment significantly reduced lung inflammation in Nrf2^+/+ , but not in Nrf2^-/- mice. Thus, our data indicate for the first time that RAGE inhibition has an essential protective role in COPD. Our observation of RAGE inhibition provided novel insight into its potential as a therapeutic target in emphysema/COPD.-Lee, H., Park, J.-R., Kim, W. J., Sundar, I. K., Rahman, I., Park, S.-M., Yang. S.-R. Blockade of RAGE ameliorates elastase-induced emphysema development and progression via RAGE-DAMP signaling.

Improved hematopoietic differentiation of human pluripotent stem cells via estrogen receptor signaling pathway

Background

Aside from its importance in reproduction, estrogen (E2) is known to regulate the proliferation and differentiation of hematopoietic stem cells in rodents. However, the regulatory role of E2 in human hematopoietic system has not been investigated. The purpose of this study is to investigate the effect of E2 on hematopoietic differentiation using human pluripotent stem cells (hPSCs).

Results

E2 improved hematopoietic differentiation of hPSCs via estrogen receptor alpha (ER-α)-dependent pathway. During hematopoietic differentiation of hPSCs, ER-α is persistently maintained and hematopoietic phenotypes (CD34 and CD45) were exclusively detected in ER-α positive cells. Interestingly, continuous E2 signaling is required to promote hematopoietic output from hPSCs. Supplementation of E2 or an ER-α selective agonist significantly increased the number of hemangioblasts and hematopoietic progenitors, and subsequent erythropoiesis, whereas ER-β selective agonist did not. Furthermore, ICI 182,780 (ER antagonist) completely abrogated the E2-induced hematopoietic augmentation. Not only from hPSCs but also from human umbilical cord bloods, does E2 signaling potentiate hematopoietic development, suggesting universal function of E2 on hematopoiesis.

Conclusions

Our study identifies E2 as positive regulator of human hematopoiesis and suggests that endocrine factors such as E2 influence the behavior of hematopoietic stem cells in various physiological conditions.

Electronic supplementary material

The online version of this article (doi:10.1186/s13578-016-0111-9) contains supplementary material, which is available to authorized users.

Generation of liver-specific TGF-α/c-Myc-overexpressing porcine induced pluripotent stem-like cells and blastocyst formation using nuclear transfer

Transgenic porcine induced pluripotent stem (iPS) cells are attractive cell sources for the development of genetically engineered pig models, because they can be expanded without senescence and have the potential for multiple gene manipulation. They are also useful cell sources for disease modeling and treatment. However, the generation of transgenic porcine iPS cells is rare, and their embryonic development after nuclear transfer (NT) has not yet been reported. We report here the generation of liver-specific oncogenes (TGF-α/c-Myc)-overexpressing porcine iPS (T/M iPS)-like cells. They expressed stem cell characteristics and were differentiated into hepatocyte-like cells that express oncogenes. We also confirmed that NT embryos derived from T/M iPS-like cells successfully developed blastocysts in vitro. As an initial approach toward porcine transgenic iPS cell generation and their developmental competence after NT, this study provides foundations for the efficient generation of genetically modified porcine iPS cells and animal models.

Decellularized Liver Extracellular Matrix as Promising Tools for Transplantable Bioengineered Liver Promotes Hepatic Lineage Commitments of Induced Pluripotent Stem Cells

Liver transplantation is the last resort for liver failure patients. However, due to the shortage of donor organs, bioengineered liver generated from decellularized whole liver scaffolds and induced pluripotent stem cell (iPSC)-derived hepatocytes (iPSC-Heps) is being studied as an alternative approach to treat liver disease. Nevertheless, there has been no report on both the interaction of iPSC-Heps with a liver extracellular matrix (ECM) and the analysis of recellularized iPSC-Heps into the whole liver scaffolds. In this study, we produced porcine iPSC-Heps, which strongly expressed the hepatic markers α-fetoprotein and albumin and exhibited hepatic functionalities, including glycogen storage, lipid accumulation, low-density lipoprotein uptake, and indocyanine green metabolism. Supplementation of ECM from porcine decellularized liver containing liver-derived growth factors stimulated the albumin expression of porcine iPSC-Heps during differentiation procedures. The iPSC-Heps were reseeded into decellularized liver scaffolds, and the recellularized liver was cultured using a continuous perfusion system. The recellularized liver scaffolds were transplanted into rats for a short term, and the grafts expressed hepatocyte markers and did not rupture. These results provide a foundation for development of bioengineered liver using stem cell and decellularized scaffolds.

Nicotine inhibits the proliferation by upregulation of nitric oxide and increased HDAC1 in mouse neural stem cells

Cigarette smoking (CS) is considered one of the major risk factors to cause neurodegenerative disorders. Nicotine is the main chemical in CS which is responsible for dysfunction of the brain as a neuroteratogen. Also, nicotine dependency is a real mental illness and disease. Recently, chronic nicotine exposure has been shown to cause oxidative/nitrosative stress leading to a deleterious condition to cellular death in different brain regions. However, little is known about the effects of nicotine on mouse neural stem cells (mNSCs). The aim of this study is to investigate the effects of nicotine on mNSCs and elucidate underlying mechanisms involved in expression of a diversity of genes regulated by nicotine. When mNSCs were isolated from the whole brain of embryonic day 16 mice treated with nicotine at vehicle, 100, 400, and 800 μM for 5 d, nicotine significantly decreased the number and size of neurospheres. In immunocytochemistry, nicotine-exposed mNSCs expressing nestin showed the shortened filaments and condensed nuclei. In RT-PCR, messenger RNA (mRNA) levels of proliferating cell nuclear antigen (PCNA) and sirtuin1 (SIRT1) were significantly decreased, while the production of nitric oxide and mRNA levels of cyclooxygenase2 (COX-2), tumor necrosis factor-alpha TNF-α, and histone deacetylase 1 (HDAC1) were increased in a dose-dependent manner. In addition, sodium butyrate and valproic acid, HDAC inhibitors, partially rescue proliferation of mNSCs via inhibition of HDAC1 expression and NO production. Taken together, these data demonstrate that prolonged exposure of nicotine decreased proliferation of mNSCs by increased NO and inflammatory cytokine through increased HDAC1. Furthermore, this study could help in the development of a therapy for nicotine-induced neurodegenerative disorder and drug abuse.

Influence of pre-diagnostic cigarette smoking on colorectal cancer survival: overall and by tumour molecular phenotype

BACKGROUND

Smoking is a risk factor for incident colorectal cancer (CRC); however, it is unclear about its influence on survival after CRC diagnosis.

METHODS

A cohort of 706 CRC patients diagnosed from 1999 to 2003 in Newfoundland and Labrador, Canada, was followed for mortality and recurrence until April 2010. Smoking and other relevant data were collected by questionnaire after cancer diagnosis, using a referent period of '2 years before diagnosis' to capture pre-diagnosis information. Molecular analyses of microsatellite instability (MSI) status and BRAF V600E mutation status were performed in tumour tissue using standard techniques. Multivariate hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated with Cox proportional hazards regression, controlling for major prognostic factors.

RESULTS

Compared with never smokers, all-cause mortality (overall survival, OS) was higher for current (HR: 1.78; 95% CI: 1.04-3.06), but not for former (HR: 1.06; 95% CI: 0.71-1.59) smokers. The associations of cigarette smoking with the study outcomes were higher among patients with ≥40 pack-years of smoking (OS: HR: 1.72; 95% CI: 1.03-2.85; disease-free survival (DFS: HR: 1.99; 95% CI: 1.25-3.19), those who smoked ≥30 cigarettes per day (DFS: HR: 1.80; 95% CI: 1.22-2.67), and those with microsatellite stable (MSS) or MSI-low tumours (OS: HR: 1.38; 95% CI: 1.04-1.82 and DFS: HR: 1.32; 95% CI: 1.01-1.72). Potential heterogeneity was noted for sex (DFS HR: 1.68 for men and 1.01 for women: P for heterogeneity=0.04), and age at diagnosis (OS: HR: 1.11 for patients aged <60 and 1.69 for patients aged ≥60: P for heterogeneity=0.03).

CONCLUSIONS

Pre-diagnosis cigarette smoking is associated with worsened prognosis among patients with CRC.

Immunolocalisation and oestrogen regulation of small proline-rich protein 2a protein in the mouse uterus

Small proline-rich protein 2a (Sprr2a) is one of the structural components of the cornified keratinocyte cell envelope that contributes to form a protective barrier in the skin against dehydration and environmental stress. Interestingly, Sprr2a mRNA is detected in the mouse uterus and is regulated by 17β-oestradiol (E2). In the present study, we investigated the effects of E2 and oestrogenic compounds on the regulation and localisation of Sprr2a protein in the mouse uterus. Immunohistochemical staining revealed that Sprr2a protein is detected only in the adult uterus, and not in the ovary, oviduct or testis. We also demonstrated that Sprr2a protein is tightly regulated by E2 in the mouse uterus and exclusively detected in luminal and glandular epithelial cells. Furthermore, Sprr2a is dose-dependently induced by oestrogenic compounds such as bisphenol A and 4-tert-octylphenol. Collectively, our studies suggest that Sprr2a protein may have a unique function in physiological events in the mouse uterus and can be used as an indicator to detect compounds with oestrogenic activity in the mouse uterus.

Oxidative stress-induced biomarkers for stem cell-based chemical screening

Stem cells have been considered for their potential in pharmaceutical research, as well as for stem cell-based therapy for many diseases. Despite the potential for their use, the challenge remains to examine the safety and efficacy of stem cells for their use in therapies. Recently, oxidative stress has been strongly implicated in the functional regulation of cell behavior of stem cells. Therefore, development of rapid and sensitive biomarkers, related to oxidative stress is of growing importance in stem cell-based therapies for treating various diseases. Since stem cells have been implicated as targets for carcinogenesis and might be the origin of "cancer stem cells", understanding of how oxidative stress-induced signaling, known to be involved in the carcinogenic process could lead to potential screening of cancer chemopreventive and chemotherapeutic agents. An evaluation of antioxidant states reducing equivalents like GSH and superoxide dismutase (SOD), as well as reactive oxygen species (ROS) and nitric oxide (NO) generation, can be effective markers in stem cell-based therapies. In addition, oxidative adducts, such as 4-hydroxynonenal, can be reliable markers to detect cellular changes during self-renewal and differentiation of stem cells. This review highlights the biomarker development to monitor oxidative stress response for stem cell-based chemical screening.

JNK Activation by Up-Regulation of iNOS on Cholesterol Accumulation Limits Neurogenesis and Induces Region-Specific DNA Damage Responses in the Subventricular Zone of NPC Mice

Abstract Aims: We explore the region-specific impact of nitric oxide (NO) on adult neural stem cell (aNSC) niches with regard to neurogenesis and NSC damage and investigate the underlying mechanisms in Niemann-Pick disease type C (NPC) mice. Results: Among the two anatomical stem-cell niches of the brain, subventricular zone (SVZ)-derived aNSCs enhanced c-Jun N-terminal kinase (JNK) activity because of excessive NO production by the cholesterol accumulation. Activated JNK interacts with γH2AX, a marker for DNA damage; however, almost none of the aNSCs in the dentate gyrus (DG) showed either JNK signaling activation or abundant DNA damage. SVZ-derived aNSCs were protected from DNA damage by the treatment of Nω-nitro-L-arginine methyl ester (L-NAME), a NO synthase (NOS) inhibitor, both in vitro and in vivo. We also observed that U18666A, an inducer of cholesterol accumulation, increased inducible NOS expression, JNK activation, and DNA damage in the wild type (WT)-aNSCs. Interestingly, we found that endogenous cholesterol efflux transporters and their regulator were less activated in the SVZ than in the DG, in both WT and NPC mice. This result explains the high vulnerability of SVZ-derived aNSCs to the cholesterol imbalance as observed in NPC mice. Innovation and Conclusion: In this study, we demonstrated that the SVZ-derived aNSCs might be major targets of NPC. Significantly, aNSCs showed different responses depending on their anatomical origins due to dissimilarities in their cholesterol transporting system and NO-dependent JNK activation. These findings can contribute to the understanding of the region-specific nature of the two SVZ and DG neurogenic niches. Antioxid. Redox Signal. 00, 000-000.