bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of endothelial cells on bone regeneration using poly(L‐lactide‐co‐1,5‐dioxepan‐2‐one) scaffolds
Authors: Xing Zhe , Xue Ying , Dånmark Staffan , Schander Kerstin , Østvold Siren , Arvidson Kristina , Hellem Sølve , Finne‐Wistrand Anna , Albertsson Ann‐Christine , Mustafa Kamal
Published: December 2010

Our recentin vitrostudy demonstrated that endothelial cells (ECs) might influence the differentiation of bone marrow stromal cells (BMSCs). Therefore, the aim of this study was to describe this effectin vivo, using a rat calvarial bone defect model. BMSCs were isolated from femurs of two‐donor Lewis rats and expanded in α‐minimum essential medium containing 10% fetal bovine serum. One fifth of BMSCs were induced and differentiated into ECs in an Endothelial Cell Growth Medium‐2 and then characterized by a flow cytometry. The remaining BMSCs were cultured in freshly prepared osteogenic stimulatory medium, containing dexamethasone, ascorbic acid and β‐glycerophosphate. Either BMSCs alone (BMSC‐group) or co‐cultured ECs/BMSCs (CO‐group) were seeded into poly(L‐lactide‐co‐1,5‐dioxepan‐2‐one) [poly(LLA‐co‐DXO)] scaffolds, cultured in spinner flasks, and then implanted into symmetrical calvarial defects prepared in recipient rats. The animals were sacrificed after 2 months. The formation of new bone was evaluated by radiography and histology and by the expression of osteogenic markers using reverse transcriptase‐polymerized chain reaction (RT–PCR). To investigate vessel formation, histological staining was performed with EC's markers. The radiographical and histological results showed more rapid bone formation in the CO‐ than in the BMSC‐group. However, the expression of EC's marker was similar on both groups by histological analysis after 2 months postoperatively. Furthermore, the CO‐group exhibited greater expression of osteogenic markers as demonstrated by RT–PCR. The results are consistent with the previousin vitrofindings that poly(LLA‐co‐DXO) scaffold might be suitable candidate for bone tissue engineering.In vivo, bone regeneration was enhanced by a construct of the polymer scaffold loaded with co‐cultured cells. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2011.
Mineral trioxide aggregate solution inhibits osteoclast differentiation through the maintenance of osteoprotegerin expression in osteoblasts
Authors: Hashiguchi Daisuke , Fukushima Hidefumi , Nakamura Midori , Morikawa Kazumasa , Yasuda Hisataka , Udagawa Nobuyuki , Maki Kenshi , Jimi Eijiro
Published: December 2010

Mineral trioxide aggregate (MTA) is a therapeutic, endodontic repair material that is reported to exhibit calcified tissue‐conductive activity. The aim of this study was to investigate whether MTA may prevent osteoclast differentiation in vitro. MTA solution, but not other commonly used retrofilling materials, such as Dycal, Super‐EBA, or intermediate restorative material (IRM) solution, dose‐dependently inhibited osteoclastogenesis in cocultures of mouse bone marrow cells (BMCs) with primary osteoblast cells (POBs) induced by 1α,25‐dihydroxyvitamin D3 [1α,25(OH)2D3]. Exogenous CaCl2 medium supplementation did not inhibit osteoclastogenesis in cocultures. Furthermore, MTA solution did not affect receptor activator of NF‐κB ligand (RANKL)‐induced osteoclastogenesis, suggesting that POBs are targets of MTA. MTA solution suppressed the 1α,25(OH)2D3‐induced reduction of osteoprotegerin (OPG) mRNA and protein production without changing RANKL expression in POBs. Consistent with this result, MTA solution did not inhibit osteoclastogenesis in cocultures of BMCs and POBs from OPG‐deficient mice. Therefore, the maintenance of OPG expression in POBs appears to be critical for the inhibitory effect of MTA solution on osteoclast differentiation. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A:, 2011.
Hematopoietic progenitor cell count, but not immature platelet fraction value, predicts successful harvest of autologous peripheral blood stem cells
Authors: Mitani Noriyuki , Yujiri Toshiaki , Tanaka Yoshinori , Tanaka Mayumi , Fujii Yasuhiko , Hinoda Yuji , Tanizawa Yukio
Published: December 2010

Mobilized stem cells in the peripheral blood (PB) must be efficiently harvested at the appropriate time before autologous PB stem cell (PBSC) transplantation. Enumeration of CD34+ cells in the PB before apheresis predicts the number of PBSCs that can be collected, but the cytometric techniques used are complex and expensive. Therefore, it is necessary to identify an alternative to the CD34+ cell count in PBSC harvest‐time monitoring. Fully automated flow cytometry using blood cell counters now allows reliable quantification of immature myeloid cells in the PB, referred to as hematopoietic progenitor cells (HPC), and reticulated platelets, expressed as the immature platelet fraction (IPF). Immature or reticulated platelets are thought to correlate with thrombopoietic activity of the marrow. Following a chemotherapy nadir, the recovery of white blood cell and platelet counts has been used to determine the right time for apheresis. Therefore, we examined whether the HPC count and IPF value could be used to predict PBSC mobilization in 20 patients with hematological malignancies. The HPC count was found to be correlated with the CD34+ cell count (r = 0.84, P < 0.01), whereas the IPF value was not (r = 0.37, P = 0.44). Therefore, the HPC count, but not the IPF value, is a possible predictor of the timing of autologous stem cell transplantation. J. Clin. Apheresis, 2011. © 2010 Wiley‐Liss, Inc.
Stem and progenitor cells for neurological repair: Minor issues, major hurdles, and exciting opportunities for paracrine‐based therapeutics
Authors: Shimada Issei S. , Spees Jeffrey L.
Published: December 2010

The transplantation of cultured stem and progenitor cells is a key element in the rapidly growing field of regenerative medicine. Based on their ability to rescue and/or repair injured tissue and partially restore organ function, multiple types of stem/progenitor cells have already entered into clinical trials. However, despite several decades of intense research, the goal to apply culture‐expanded stem/progenitor cells in a manner that can effectively replace cells after injury has yet to be realized. Many sources of potentially useful cells are available, but something is clearly missing. In addition, recent studies suggest that paracrine effects of secreted or released factors are responsible for most of the benefits observed after cell transplantation, rather than direct cell replacement. These data call into question the need for cell transplantation for many types of therapy, in particular for acute injuries such as myocardial infarction and stroke. In this review, we examine current progress in the area of cell transplantation and minor issues and major hurdles regarding the clinical application of different cell types. We discuss the “paracrine hypothesis” for the action of transplanted stem/progenitor cells as an opportunity to identify defined combinations of biomolecules to rescue and/or repair tissues after injury. Although many of the concepts in this review will apply to multiple injury/repair systems, we will focus primarily on stem/progenitor cell‐based treatments for neurological disorders and stroke. J. Cell. Biochem. 112: 374–380, 2011. © 2010 Wiley‐Liss, Inc.
New insights into the inactivation of gastric tumor suppressor RUNX3: The role of H. pylori infection
Authors: Tsang Ying‐Hung Nicole , Lamb Acacia , Chen Lin‐Feng
Published: December 2010

Runt‐related transcription factor 3, or RUNX3, is a tumor suppressor in gastric cancer. Inactivation of RUNX3 is causally associated with the genesis of gastric cancer, since RUNX3 is frequently inactivated in gastric cancers by hemizygous deletion, hypermethylation of its promoter, or protein mislocalization. Infection with Helicobacter pylori is the strongest risk factor for the development of gastric cancer. Recent studies have indicated that H. pylori infection plays an important role in the inactivation of RUNX3, and that this inactivation contributes to the pathogenesis of H. pylori. Here we summarize these recent advances and discuss their significances in understanding the initiation and development of gastric cancer. J. Cell. Biochem. 112: 381–386, 2011. © 2010 Wiley‐Liss, Inc.
Phloroglucinol derivative MCPP induces cell apoptosis in human colon cancer
Authors: Huang Ssu‐Ming , Cheung Chi‐Wai , Chang Chih‐Shiang , Tang Chih‐Hsin , Liu Ju‐Fang , Lin Yu‐Hsin , Chen Jia‐Hong , Ko Shihi‐Hsun , Wong Kar‐Lok , Lu Dah‐Yuu
Published: December 2010

This study is the first to investigate the anticancer effects of the new phloroglucinol derivative (3,6‐bis(3‐chlorophenylacetyl)phloroglucinol; MCPP) in human colon cancer cells. MCPP induced cell death and antiproliferation in three human colon cancer, HCT‐116, SW480, and Caco‐2 cells, but not in primary human dermal fibroblast cells. MCPP‐induced concentration‐dependent apoptotic cell death in colon cancer cells was measured by fluorescence‐activated cell sorter (FACS) analysis. Treatment of HCT‐116 human colon cancer cells with MCPP was found to induce a number of signature endoplasmic reticulum (ER) stress markers; and up‐regulation of CCAAT/enhancer‐binding protein homologous protein (CHOP) and glucose‐regulated protein (GRP)‐78, phosphorylation of eukaryotic initiation factor‐2α (eIF‐2α), suggesting the induction of ER stress. MCPP also increased GSK3α/β(Tyr270/216) phosphorylation and reduced GSK3α/β(Ser21/9) phosphorylation time‐dependently. Transfection of cells with GRP78 or CHOP siRNA, or treatment of GSK3 inhibitor SB216163 reduced MCPP‐mediated cell apoptosis. Treatment of MCPP also increased caspase‐7, caspase‐9, and caspase‐3 activity. The inhibition of caspase activity by z‐DEVE‐FMK or z‐VAD‐FMK significantly reduced MCPP‐induced apoptosis. Furthermore, treatment of GSK3 inhibitor SB216763 also dramatically reversed MCPP‐induced GRP and CHOP up‐regulation, and pro‐caspase‐3 and pro‐caspase‐9 degradation. Taken together, the present study provides evidences to support that GRP78 and CHOP expression, and GSK3α/β activation in mediating the MCPP‐induced human colon cancer cell apoptosis. J. Cell. Biochem. 112: 643–652, 2011. © 2010 Wiley‐Liss, Inc.
Direct transcriptional targets of sex steroid hormones in bone
Authors: Krum Susan A.
Published: December 2010

The sex steroid hormones, androgens and estrogens, via their respective nuclear receptors, regulate bone mineral density in humans and mice. Very little is known about the direct targets of the androgen and estrogen receptors in bone cells. First, models of hormone and receptor deficiency in mouse and human bone are discussed. This review then focuses on the direct targets of the receptors in osteoblasts and osteoclasts. A direct target of a NR is defined here as a gene that is regulated by NR binding to the DNA (either through DNA binding or association with a DNA binding protein) at an enhancer or promoter of that gene. The experimental evidence that illustrates androgen and estrogen gene regulation in osteoblasts and osteoclasts will be summarized and compared with the phenotype of the hormones in vivo. J. Cell. Biochem. 112: 401–408, 2011. © 2011 Wiley‐Liss, Inc.
Key roles of histone methyltransferase and demethylase in leukemogenesis
Authors: Yoshimi Akihide , Kurokawa Mineo
Published: December 2010

A growing body of evidence has underlined the involvement of histone methyltransferases and demethylases in leukemia development. These findings can be roughly classified into two categories according to their association with leukemia. On the one hand, these histone modifiers are recruited to DNA by specific affinities of aberrantly expressed transcription factors or fusion proteins, and induce chromatin modifications to regulate target gene expression. Epigenetic regulators may function as oncogenes in this context. On the other hand, recent studies have identified inactivating mutations of some key histone modulators in myeloid malignancies and these results suggest that they act as tumor suppressors. Profound understanding of these findings in the two categories will help us consider clinical applications of epigenetic drugs. In this prospect we will review the leukemogenic mechanisms clarified by the epigenetic approach and the current findings on genetic aberrations in each methyltransferase or demethylase, and discuss the potential of medical intervention in leukemia or leukemia stem cells targeting histone modifiers. J. Cell. Biochem. 112: 415–424, 2011. © 2010 Wiley‐Liss, Inc.
Molecular mechanisms underlying the inhibition of IFN‐γ‐induced, STAT1‐mediated gene transcription in human macrophages by simvastatin and agonists of PPARs and LXRs
Authors: Li Na , Salter Rebecca C. , Ramji Dipak P.
Published: December 2010

PPARs and LXRs are ligand‐activated transcription factors that are emerging as promising therapeutic targets for limiting atherosclerosis, an inflammatory disorder orchestrated by cytokines. The potent anti‐atherogenic actions of these nuclear receptors involve the regulation of glucose and lipid metabolism along with attenuation of the inflammatory response. Similarly, cholesterol‐lowering drugs, statins, inhibit inflammation. Unfortunately, the mechanisms underlying such inhibitory actions of these agents in human macrophages are poorly understood and were therefore investigated in relation to IFN‐γ, a key pro‐atherogenic cytokine, which mediates its cellular effects mainly through STAT1. Simvastatin and PPAR agonists had no effect on the IFN‐γ‐induced, phosphorylation‐mediated activation of STAT1 and its DNA binding but attenuated its ability to activate gene transcription. On the other hand, LXR activators attenuated both DNA binding and trans‐activation potential of STAT1 induced by IFN‐γ. These studies reveal differences in the mechanism of action of agonists of PPARs (and simvastatin) and LXRs on the IFN‐γ‐induced, STAT1‐mediated gene transcription in human macrophages. J. Cell. Biochem. 112: 675–683, 2011. © 2010 Wiley‐Liss, Inc.
Modulation of oxidative stress responses in the human retinal pigment epithelium following treatment with vitamin C
Authors: Yin Jinggang , Thomas Fridtjof , Lang John C. , Chaum Edward
Published: December 2010

Oxidative stress (OS) in the retina plays an important role in the development and progression of age‐related macular degeneration (AMD). Our previous work has shown that OS can quantitatively regulate the expression of AP‐1 family genes in the retinal pigment epithelium (RPE). In this study, we sought to determine whether AP‐1 genes can be used as cellular biomarkers of OS to evaluate the efficacy of ascorbate, the major aqueous‐phase antioxidant in the blood, in reducing OS in RPE cells in vitro. Human ARPE19 cells were pretreated with increasing levels of ascorbate (0–500 µM) for 3 days which was then removed from the medium. OS was induced 24 h later by the addition of hydrogen peroxide for 1–4 h, to bring the final media concentration of H2O2 to 500 µM. FosB, c‐Fos, and ATF3 gene expression was examined from 0 to 24 h after OS. Pretreatment with 200 µM ascorbate maximally reduced the transcriptional OS response of AP‐1 genes by up to 87% after 1 and 4 h, compared to controls. One hundred micromolar of ascorbate provided a statistically significant, but far more modest effect. Ascorbate supplementation of 100–200 µM appears to strongly inhibit OS‐induced activation of AP‐1 in vitro, but pretreatment with higher levels of ascorbate conferred no additional advantage. These studies suggest that there are optimal levels of antioxidant supplementation to the RPE in vitro. Laboratory assays based upon transcription factor biomarkers may be useful to define beneficial molecular responses to new antioxidants, alternative dosing regimens, and to explore therapeutic efficacy in OS models in vitro. J. Cell. Physiol. 226: 2025–2032, 2011. © 2010 Wiley‐Liss, Inc.
Differential regulation of the humanCYP11A1promoter in mouse brain and adrenals
Authors: Chiang Yen‐Feng , Lin Hui‐Ting , Hu Ji‐Wei , Tai Yu‐Chen , Lin Yu‐Chi , Hu Meng‐Chun
Published: December 2010

CYP11A1encodes the first enzyme of steroid biosynthesis, cytochrome P450scc. The expression ofCYP11A1in the nervous system allows neurosteroids to be synthesized de novo. In the classic steroidogenic tissues, adrenals and gonads, the key regulator controllingCYP11A1expression is steroidogenic factor‐1 (SF‐1), but the transcriptional regulation ofCYP11A1in the brain is unclear. We recently used the 4.4‐kb regulatory region of the humanCYP11A1gene to drive Cre recombinase expression in the diencephalon and midbrain. In this study, we characterized the regional‐specific expression of Cre reporter in the SCC‐Cre transgenic brain using a transient Cre/ROSA26R transgenic system. Mutation of either the upstream or proximal SF‐1 binding site did not affect brainCYP11A1promoter activity. The upstream SF‐1 binding site, however, is required forCYP11A1promoter function in the embryonic adrenals. The 3.8‐kb promoter, like the 4.4‐kb length promoter, directed Cre expression in the diencephalon, midbrain and olfactory epithelium, whereas Cre expression controlled by the 2.7‐kb promoter was only observed in the caudal part of midbrain. This suggests that the 5′‐flanking region between 3.8 and 2.7 kb contains a crucial element for activation ofCYP11A1promoter in the diencephalon, olfactory epithelium and the anterior part of midbrain. Thus we have identified regions of the promoter that controlCYP11A1expression in the brain and embryonic adrenals. J. Cell. Physiol. 226: 1998–2005, 2011. © 2010 Wiley‐Liss, Inc.
Activation and induction of cytosolic phospholipase A2 by TNF‐α mediated through Nox2, MAPKs, NF‐κB, and p300 in human tracheal smooth muscle cells
Authors: Lee Chiang‐Wen , Lin Chih‐Chung , Lee I‐Ta , Lee Hui‐Chun , Yang Chuen‐Mao
Published: December 2010

Cytosolic phospholipase A2 (cPLA2) plays a pivotal role in mediating agonist‐induced arachidonic acid (AA) release for prostaglandin (PG) synthesis during inflammation triggered by tumor necrosis factor‐α (TNF‐α). However, the mechanisms underlying TNF‐α‐induced cPLA2 expression and PGE2 synthesis in human tracheal smooth muscle cells (HTSMCs) remain unknown. Here, we report that TNF‐α‐induced cPLA2 protein and mRNA expression, PGE2 production, and phosphorylation of p42/p44 MAPK, p38 MAPK, and JNK1/2, which were attenuated by pretreatment with a ROS scavenger [N‐acetyl‐L‐cysteine, (NAC)] and the inhibitors of NADPH oxidase [apocynin (APO) and diphenyleneiodonium chloride (DPI)], MEK1/2 (U0126), p38 MAPK (SB202190), and JNK1/2 (SP600125) or transfection with siRNA of Nox2, p47phox, MEK1, p42, p38, or JNK2. TNF‐α‐induced cPLA2 expression was also inhibited by pretreatment with a selective NF‐κB inhibitor [helenalin (HLN)] or transfection with dominant negative mutants of NF‐κB inducing kinase (NIK) or IκB kinase (IKK)α/β. TNF‐α‐induced NF‐κB translocation was blocked by pretreatment with NAC, DPI, APO, or HLN, but not by U0126, SB202190, or SP600125. In addition, pretreatment with curcumin (a p300 inhibitor) or transfection with p300 siRNA blocked cPLA2 expression and PGE2 synthesis induced by TNF‐α. We further confirmed that p300 was associated with the cPLA2 promoter which was dynamically linked to histone H4 acetylation stimulated by TNF‐α, determined by chromatin immunoprecipitation assay. Association of p300 and histone H4 to cPLA2 promoter was inhibited by U0126, SB202190, and SP600125. These results suggested that in HTSMCs, activation of p47phox, MAPKs, NF‐κB, and p300 is essential for TNF‐α‐induced cPLA2 expression and PGE2 release. J. Cell. Physiol. 226: 2103–2114, 2011. © 2010 Wiley‐Liss, Inc.
Pulmonary microvascular endothelial cells from bleomycin‐induced rats promote the transformation and collagen synthesis of fibroblasts
Authors: Yin Qian , Nan Hai‐Yan , Zhang Wen‐Hu , Yan Lin‐Feng , Cui Guang‐Bin , Huang Xiao‐Feng , Wei Jing‐Guo
Published: December 2010

Accumulation and activation of myofibroblasts are the hallmark of progressive pulmonary fibrosis, and the resident fibroblasts are the major source of myofibroblasts. However, the key factors involved in the transformation of fibroblasts are unknown. Pulmonary microvascular endothelial cells (PMVECs), major effector cells against pathogenesis in early stages of the disease, can secrete cytokines to induce the differentiation of mesenchymal cells. We speculated that PMVECs could secrete pro‐fibrotic cytokines and promote the transformation of fibroblasts into myofibroblasts. Accordingly, we established a co‐culture system with PMVECs and fibroblasts to examine the specific transformation and collagen synthesis of the co‐cultured fibroblasts by FACS and Western blot, prior to and after treatment with neutralizing antibodies against transforming growth factor‐beta1 (TGF‐β1) and connective tissue growth factor (CTGF). We also analyzed expression of TGF‐β1 and CTGF in PMVECs. The synthesis and secretion of TGF‐β1 and CTGF protein were up‐regulated in PMVECs isolated from bleomycin (BLM)‐treated rats, most prominently at 7 days post‐instillation. We showed that the PMVECs isolated from BLM‐induced rats could induce the transformation of normal fibroblasts and their secretion of collagen I, which was inhibited by both neutralizing anti‐TGF‐β1 and anti‐CTGF antibodies. Therefore, up‐regulation of TGF‐β1 and CTGF in PMVECs plays an important role in activation, transformation, and collagen synthesis of fibroblasts; in particular, these effects in PMVECs are likely to be the key factors for activation and stimulation of static fibroblasts in lung interstitium in early stages of pulmonary fibrosis disease. J. Cell. Physiol. 226: 2091–2102, 2011. © 2010 Wiley‐Liss, Inc.
Leptin up‐regulates pro‐inflammatory cytokines in discrete cells within mouse colon
Authors: Padidar Sara , Farquharson Andrew J. , Williams Lynda M. , Kelaiditi Eirini , Hoggard Nigel , Arthur John R. , Drew Janice E.
Published: December 2010

Dysregulation of leptin associated with obesity is implicated in obesity‐related colon cancer, but mechanisms are elusive. Increased adiposity and elevated plasma leptin are associated with perturbed metabolism in colon and leptin receptors are expressed on colon epithelium. We hypothesise that obesity increases the sensitivity of the colon to cancer by disrupting leptin‐regulated gene targets within colon tissues. PCR arrays were used to firstly identify leptin responsive genes and secondly to identify responses to leptin challenge in wild‐type mice, or those lacking leptin (ob/ob). Leptin‐regulated genes were localised in the colon using in situ hybridisation. IL6, IL1β and CXCL1 were up‐regulated by leptin and localised to discrete cells in gut epithelium, lamina propria, muscularis and at the peritoneal serosal surface. Leptin regulates pro‐inflammatory genes such as IL6, IL1β and CXCL1, and might increase the risk of colon cancer among obese individuals. J. Cell. Physiol. 226: 2123–2130, 2011. © 2010 Wiley‐Liss, Inc.
Resistin induces monocyte–endothelial cell adhesion by increasing ICAM‐1 and VCAM‐1 expression in endothelial cells via p38MAPK‐dependent pathway
Authors: Hsu Wei‐Yen , Chao Yu‐Wen , Tsai Ying‐Lan , Lien Chih‐Chan , Chang Chao‐Fu , Deng Ming‐Chung , Ho Low‐Tone , Kwok Ching Fai , Juan Chi‐Chang
Published: December 2010

Resistin, firstly reported as an adipocyte‐specific hormone, is suggested to be an important link between obesity and diabetes. Recent studies have suggested an association between resistin and atherogenic processes. The adhesion of circulating monocytes to endothelial cells is a critical step in the early stages of atherosclerosis. The purpose of the present study was to investigate the effect of resistin on the adhesion of THP‐1 monocytes to human umbilical vein endothelial cells (HUVECs) and the underlying mechanism. Our results showed that resistin caused a significant increase in monocyte adhesion. In exploring the underlying mechanisms of resistin action, we found that resistin‐induced monocyte adhesion was blocked by inhibition of p38MAPK activation using SB203580 and SB202190. Furthermore, resistin increased the expression of intercellular adhesion molecule‐1 (ICAM‐1) and vascular cell adhesion molecule‐1 (VCAM‐1) by HUVECs and these effects were also p38MAPK‐dependent. Resistin‐induced monocyte adhesion was also blocked by monoclonal antibodies against ICAM‐1 and VCAM‐1. Taken together, these results show that resistin increases both the expression of ICAM‐1 and VCAM‐1 by endothelial cells and monocyte adhesion to HUVECs via p38MAPK‐dependent pathways. J. Cell. Physiol. 226: 2181–2188, 2011. © 2010 Wiley‐Liss, Inc.
Endothelin‐1 exacerbates lipid accumulation by increasing the protein degradation of the ATP‐binding cassette transporter G1 in macrophages
Authors: Lin Chun‐Yueh , Lee Tzong‐Shyuan , Chen Chin‐Chang , Chang Cheng‐An , Lin Yan‐Jie , Hsu Yung‐Pei , Ho Low‐Tone
Published: December 2010

Endothelin‐1 (ET‐1), a potent proatherogenic vasoconstrictive peptide, is known to promote macrophage foam cell formation via mechanisms that are not fully understood. Excessive lipid accumulation in macrophages is a major hallmark during the early stages of atherosclerotic lesions. Cholesterol homeostasis is tightly regulated by scavenger receptors (SRs) and ATP‐binding cassette (ABC) transporters during the transformation of macrophage foam cells. The aim of this study was to investigate the possible mechanisms by which ET‐1 affects lipid accumulation in macrophages. Our results demonstrate that oxidized low‐density lipoprotein (oxLDL) treatment increases lipid accumulation in rat bone marrow‐derived macrophages. Combined treatment with ET‐1 and oxLDL significantly exacerbated lipid accumulation in macrophages as compared to treatment with oxLDL alone. The results of Western blotting show that ET‐1 markedly decreased the ABCG1 levels via ET type A and B receptors and activation of the phosphatidylinositol 3‐kinase pathway; however, ET‐1 had no effect on the protein expression of CD36, SR‐BI, SR‐A, or ABCA1. In addition, real‐time PCR analysis showed that ET‐1 treatment did not affect ABCG1 mRNA expression. We also found that ET‐1 decreases ABCG1 possibly due to the enhancement of the proteosome/calpain pathway‐dependent degradation of ABCG1. Moreover, ET‐1 significantly reduced the efficiency of the cholesterol efflux in macrophages. Taken together, these findings suggest that ET‐1 may impair cholesterol efflux and further exacerbate lipid accumulation during the transformation of macrophage foam cells. J. Cell. Physiol. 226: 2198–2205, 2011. © 2010 Wiley‐Liss, Inc.
The p53 tumor suppressor protein regulates hematopoietic stem cell fate
Authors: Asai Takashi , Liu Yan , Bae Narae , Nimer Stephen D.
Published: December 2010

The p53 tumor suppressor protein is a key transcription factor that regulates several signaling pathways involved in the cell's response to stress. Through stress‐induced activation, p53 accumulates and triggers the expression of target genes that protect the genetic integrity of all cells including hematopoietic stem cells (HSCs). These protective mechanisms include cell‐cycle arrest, DNA repair, induction of apoptosis, or initiation of senescence. In addition to its function under stress conditions, p53 has important functions during steady‐state hematopoiesis, regulating HSC quiescence and self‐renewal. In addition, it appears that p53 levels affect HSC competition for the hematopoietic niche, with the less p53 activated HSCs preferentially surviving. The specific genes and precise mechanisms underlying p53's effects on normal HSCs are slowly being clarified. p53 also plays an important role in leukemia stem cell (LSC) behavior, with p53 loss affecting drug resistance and disease progression. Pharmacologic activation of p53 function could overcome the adverse impact of p53 inactivation in LSCs. Thus, understanding the p53 regulatory mechanisms active in HSCs and LSCs may promote the development of new therapeutic strategies that could eliminate the population of largely quiescent LSCs. J. Cell. Physiol. 226: 2215–2221, 2011. © 2010 Wiley‐Liss, Inc.
Expression of members of the miRNA17–92 cluster during development and in carcinogenesis
Authors: Jevnaker Anne‐Marthe , Khuu Cuong , Kjøle Elisabeth , Bryne Magne , Osmundsen Harald
Published: December 2010

The six microRNAs (miRNA) encoded by the miR‐17–92 cluster, also named oncomir‐1, have been associated with carcinogenesis and typically exhibit‐increased expression in tumors. Despite the well‐established role for the miR‐17–92 cluster in an oncogenic network, the physiological function of these miRNAs in normal tissues remains unresolved. In order to investigate whether there are similar patterns of miR‐17–92 expression during embryogenesis and carcinogenesis, we have preformed a systematic study of the expression in cultured carcinoma cells, cultured primary human keratinocytes (KC), and during development of some murine tissues. Both levels of expression of the primary transcript (pri‐miRNA) and levels of expression of the individual members of the cluster were monitored. Irrespectively of tissue examined we found that the level of expression decreased markedly during development. With cultured primary human KCs their levels of expression of some of these microRNAs decreased as the number of cell passages increased. Their levels of expression in cultured carcinoma cells, in contrasts, increased, or remained unchanged, with increasing number of cell passages. The results suggest these microRNAs are involved in the regulation of foetal development and that they may promote proliferation and inhibit differentiation during embryogenesis and carcinogenesis. Additionally, the six microRNAs exhibit variable tissue expression, suggesting selective processing of these microRNAs. J. Cell. Physiol. 226: 2257–2266, 2011. © 2010 Wiley‐Liss, Inc.
R‐Ras interacts with filamin a to maintain endothelial barrier function
Authors: Griffiths G.S. , Grundl M. , Allen J.S. , Matter M.L.
Published: December 2010

The molecular mechanisms regulating vascular barrier integrity remain incompletely elucidated. We have previously reported an association between the GTPase R‐Ras and repeat 3 of Filamin A (FLNa). Loss of FLNa has been linked to increased vascular permeability. We sought to determine whether FLNa's association with R‐Ras affects endothelial barrier function. We report that in endothelial cells endogenous R‐Ras interacts with endogenous FLNa as determined by co‐immunoprecipitations and pulldowns with the FLNa‐GST fusion protein repeats 1–10. Deletion of FLNa repeat 3 (FLNaΔ3) abrogated this interaction. In these cells FLNa and R‐Ras co‐localize at the plasma membrane. Knockdown of R‐Ras and/or FLNa by siRNA promotes vascular permeability, as determined by TransEndothelial Electrical Resistance and FITC‐dextran transwell assays. Re‐expression of FLNa restored endothelial barrier function in cells lacking FLNa whereas re‐expression of FLNaΔ3 did not. Immunostaining for VE‐Cadherin in cells with knocked down R‐Ras and FLNa demonstrated a disorganization of VE‐Cadherin at adherens junctions. Loss of R‐Ras and FLNa or blocking R‐Ras function via GGTI‐2133, a selective R‐Ras inhibitor, induced vascular permeability and increased phosphorylation of VE‐Cadherin (Y731) and Src (Y416). Expression of dominant negative R‐Ras promoted vascular permeability that was blocked by the Src inhibitor PP2. These findings demonstrate that maintaining endothelial barrier function is dependent upon active R‐Ras and association between R‐Ras and FLNa and that loss of this interaction promotes VE‐Cadherin phosphorylation and changes in downstream effectors that lead to endothelial leakiness. J. Cell. Physiol. 226: 2287–2296, 2011. © 2010 Wiley‐Liss, Inc.
Macrophage‐conditioned medium inhibits the activation of cyclin‐dependent kinase 2 by adipogenic inducers in 3T3‐L1 preadipocytes
Authors: Ide Jennifer , Gagnon AnneMarie , Molgat André S.D. , Landry Anne , Foster Charlie , Sorisky Alexander
Published: December 2010

Macrophage infiltration into adipose tissue, associated with obesity, is thought to contribute to abnormal adipose tissue remodeling, low‐grade inflammation, and insulin resistance. Medium conditioned by macrophages (MacCM) inhibits 3T3‐L1 and human adipocyte differentiation, as well as early adipogenic cell cycle events including MCE and retinoblastoma protein (Rb) phosphorylation. Our objective was to determine if the inhibition of Rb phosphorylation was linked to changes in cell cycle‐related proteins. We treated 3T3‐L1 preadipocytes with adipogenic inducers for 24 h in control medium versus J774A.1‐MacCM. The differentiation‐induced mRNA and protein expression of cyclin A, an activator of cyclin‐dependent kinase (cdk) 2 which phosphorylates Rb, was inhibited by 82% and 73%, respectively, by J774A.1‐MacCM; adipogenic expression of Myc, a transcriptional regulator of cyclin A, was also suppressed significantly. Consistent with the reduction in cyclin A levels, the activation of cdk2 by adipogenic inducers was inhibited by 75% by J774A.1‐MacCM. J774A.1‐MacCM also lowered levels of cyclins D1 and D2. Inhibition studies demonstrated that platelet‐derived growth factor, an anti‐adipogenic factor found in J774A.1‐MacCM, was not responsible for the inhibitory effect on differentiation. The anti‐adipogenic effect of J774A.1‐MacCM was resistant to proteinase K and heat treatment, and was present in a <3 kDa fraction. Our data indicate that J774A.1‐MacCM interferes with the upregulation of cyclin A levels and cdk2 activity that are required for Rb phosphorylation and MCE in 3T3‐L1 adipogenesis. J. Cell. Physiol. 226: 2297–2306, 2011. © 2010 Wiley‐Liss, Inc.
Effects of insulin and high glucose on mobilization of slo1 BKCa channels in podocytes
Authors: Kim Eun Young , Dryer Stuart E.
Published: December 2010

Podocytes are dynamic polarized cells that lie on the surface of glomerular capillaries and comprise an essential component of the glomerular filitration barrier. Podocytes are affected in the earliest stages of diabetic nephropathy and insulin signaling to podocytes is essential for normal glomerular function. Large‐conductance Ca2+‐activated K+ channels (BKCa channels) encoded by the Slo1 gene are expressed in podocytes in a complex with multiple glomerular slit diaphragm proteins including nephrin, TRPC6 channels, and several different actin‐binding proteins. Here we show that insulin increases cell surface expression of podocyte BKCa channels, which is accompanied by a corresponding increase in the density of current flowing through these channels. Insulin stimulation of BKCa channels was detectable in 15 min and required activation of both Erk and Akt signaling cascades. Exposure to high glucose (36.1 mM) for 24 h caused a marked reduction in the steady‐state surface expression of BKCa channels as well as of the slit diaphragm signaling molecule nephrin. High glucose treatment also abolished the stimulatory effects of insulin on BKCa current density, although insulin continued to increase phosphorylation of Erk and Akt under those conditions. Therefore, in contrast to most other cell types, high glucose abrogates the effects of insulin in podocytes at relatively distal steps in its signaling pathway. Insulin stimulation of BKCa channels in podocytes may prepare podocytes to adapt to changes in pressure gradients that occur during postprandial hyperfiltration. J. Cell. Physiol. 226: 2307–2315, 2011. © 2010 Wiley‐Liss, Inc.
A case of an epignathus with intracranial extension appearing as a persistently open mouth at 16 weeks and subsequently diagnosed at 20 weeks of gestation
Authors: Calda Pavel , Novotná Michaela , Čutka David , Břešt'ák Miroslav , Hašlík Lubomír , Goldová Barbara , Vítková Ivana , Vaněčková Manuela , Seidl Zdeněk
Published: December 2010

We report a rare case of oral mass (epignathus) with intracranial extension originally suspected antenatally at 16 weeks' gestation because of a persistent open mouth. Postmortem MRI and pathologic examination of the fetus confirmed an oral teratoma with bilateral ventricular dilatation, corpus callosum agenesis, and a neuroepithelial intracranial cyst. The relevant literature regarding this anomaly is reviewed. © 2010 Wiley Periodicals, Inc. J Clin Ultrasound, 2011
Multi‐residue analysis of pesticides in tea by online SEC‐GC/MS
Authors: Xu Xiao‐Min , Yu Cun , Han Jian‐Long , Li Jia‐Ping , El‐Sepai Fawzi , Zhu Yan , Huang Bai‐Fen , Cai Zeng‐Xuan , Wu Hong‐Wei , Ren Yi‐Ping
Published: December 2010

A multi‐residue method for the analysis of pesticides in tea was developed by online size exclusion chromatography (SEC)‐GC/MS with full scan mode. The sample was fortified with chlorpyrifos‐d10 isotope internal standard and extracted by acetonitrile. After purification by primary secondary amine sorbent and solvent exchange by SEC mobile phase, the sample was detected by online SEC‐GC/MS. The purification result of the online system was evaluated by comparing the correlation between Chinese cabbage and tea matrix. The factors for method optimization included sample preparation, matrix effects and the instrument parameters of each online component. Scatter plot was introduced in this study to directly illustrate the results of the condition optimization and matrix effects in the online system. For most of the pesticides, the average recoveries ranged from 70 to 130% and the RSD were below 15%. The feasibility of the application of full scan mode in multi‐residue determination of trace amounts of pesticides (LODs below 0.01 mg/kg) in a complex matrix was discussed.
Relationship between the interleukin-28b gene polymorphism and the histological severity of hepatitis C virus-induced graft inflammation and the response to antiviral therapy after liver transplantation
Authors: Eurich Dennis , Boas-Knoop Sabine , Ruehl Martin , Schulz Maria , Carrillo Esperanza D. , Berg Thomas , Neuhaus Ruth , Neuhaus Peter , Neumann Ulf Peter , Bahra Marcus
Published: December 2010

Up to 30% of liver transplants will develop graft cirrhosis within 5 years after liver transplantation (LT) due to recurrent HCV-infection forwarding accelerated graft damage. Genetic variants of cytokines involved in the immune response may contribute to the degree of graft inflammation, fibrosis progression, and antiviral therapy outcome. The aim of our study was to analyze biochemical and histological inflammation extent based on protocol liver biopsies and to evaluate the role of genetic variants of IL-28b in HCV-related graft disease and antiviral treatment response. 183 patients, who underwent liver transplantation for HCV-induced liver disease, were genotyped for IL-28b (rs8099917, G ≥ T) by TaqMan Genotyping Assay. 56 of 159 patients have been successfully treated with interferon-based antiviral therapy. 605 protocol liver biopsies performed 0.5 to 10 and more than 10 years after transplantation were evaluated according to Desmet and Scheuer classification of inflammation and fibrosis. Prevalence of IL-28b-genotypes was correlated with histological severity of graft damage, levels of aminotransferases, occurrence of acute cellular rejection, pre-treatment viremia, and antiviral therapy outcome. Significant association of IL-28b-genotype distribution was observed to the median grade of inflammation (p < 0.001), mean levels of aminotransferases (ALT: p = 0.001, AST: p = 0.003), median pre-treatment viremia level within 1 year after LT (p = 0.046) and interferon-based antiviral therapy failure (p < 0.001). Among successfully treated patients, G-allele was significantly less frequent, and the genotype GG was not present at all. No differences were observed regarding acute cellular rejection (p = 0.798) and fibrosis stages (p = 0.586). IL-28b polymorphism seems to influence the degree of graft inflammation at biochemical and histological levels. G-allele might serve as a marker for graft inflammation and as a predictor for unfavorable antiviral therapy outcome in HCV-re-infected LT-population. Liver Transpl, 2011. © 2011 AASLD.
Reversible Conformational Transitions of a Polymer Brush Containing Boronic Acid and its Interaction with Mucin Glycoprotein
Authors: Ivanov Alexander E. , Solodukhina Nadezda , Wahlgren Marie , Nilsson Lars , Vikhrov Alexander A. , Nikitin Maxim P. , Orlov Alexey V. , Nikitin Petr I. , Kuzimenkova Marina V. , Zubov Vitali P.
Published: December 2010

Reversible changes of the height of a polymer brush containing phenylboronic acid were studied. The polymer brush thickness underwent reversible changes of 0.5–1 nm, in response to the changes in composition of the contacting aqueous phase from deionized water to bicarbonate buffer and vice versa, apparently due to the conformational transition of the weak polyelectrolyte to the more extended electrically charged state. Adsorption of mucin glycoprotein to the polymer brush took place due to boronate/sugar interactions between the glycoprotein and the graft copolymer and resulted in further increase of the brush height by ca. 1.5 nm, as observed by means of spectral correlation spectroscopy and ellipsometry.

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Novel Oligonucleotide Carrier as Scavenger for Reactive Oxygen Species
Authors: Ikeda Yutaka , Suzuki Rie , Yoshitomi Toru , Nagasaki Yukio
Published: December 2010

A novel oligonucleotide carrier which can scavenge ROS is described. The synthesized graft polymer is composed of a PEG segment and a TEMPO‐containing hydrophobic segment for scavenging ROS. This graft polymer can form a PIC through electrostatic interaction with oligonucleotides such as siRNA. The amount of ROS was monitored by fluorescence measurements using H2DCFDA as a probe, and it was confirmed that the ROS level was effectively suppressed. The cellular uptake of PIC containing the fluorescence‐labeled oligonucleotide was evaluated by fluorescence microscopy. Delivered siRNA suppressed the expression of the mRNA. The prepared graft copolymer is thus a promising candidate as a novel oligonucleotide carrier which also reduces ROS damage generated by cationic polymer carriers.

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(Coixan polysaccharide)‐graft‐Polyethylenimine Folate for Tumor‐Targeted Gene Delivery
Authors: Jiang Qiying , Shi Peihua , Li Chunyan , Wang Qingqing , Xu Fujian , Yang Wantai , Tang Guping
Published: December 2010

CP‐PEI‐FA was prepared as an effective vector for in vitro and in vivo tumor‐targeted gene delivery. The structures of the polymers were characterized, and their DNA condensation capability, particle sizes, zeta potentials, cytotoxicity and in vitro/in vivo transfection were examined. The cytotoxicity of CP‐PEI‐FA was significantly lower than that of PEI 25 kDa and close to that of PEI 1200. The in vitro transfection of CP‐PEI‐FA was tested in C6 and HeLa cells (FR‐positive cells) and A549 cells (FR‐negative cells). CP‐PEI‐FA showed a high targeting specificity and good gene transfection efficiency in FR‐positive cells. These results indicate that CP‐PEI‐FA is a safe and effective polyplex‐forming agent for both in vitro and in vivo transfection of plasmid DNA.

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Easy Fabrication and Morphology Control of Supramolecular Liquid‐Crystalline Polymer Microparticles
Authors: Liu Hui , Kobayashi Takaomi , Yu Haifeng
Published: December 2010

A novel kind of supramolecular liquid‐crystalline polymer (SLCP) microparticles was successfully fabricated with an azopyridyl polymer and sebacic acid by combining a simple self‐organized precipitation method with hydrogen bonding interactions. Upon slow evaporation of a mixed solution of a volatile good solvent and a nonvolatile poor one, walnutlike microparticles showing wrinkled surfaces and LC natures were obtained. The diacid might play a crucial role in the formation of SLCP particles. Without addition of the diacid, neither wrinkled surfaces nor LC natures were observed in azopyridyl polymer microparticles. The fabricated SLCP microparticle possessed not only photoresponsive properties (due to azopyridyl groups) but also LC ordering, which might enable them to find advanced applications.

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The deep inferior epigastric artery perforator flap for autologous reconstruction of large partial mastectomy defects
Authors: Enajat Morteza , Rozen Warren M. , Whitaker Iain S. , Smit Jeroen M. , Van Der Hulst Rene R. W. J. , Acosta Rafael
Published: December 2010

Background:

Breast conservation surgery in the treatment of early stage breast cancer has become increasingly utilized as a means to avoiding mastectomy. While partial mastectomy defects (PMDs) may often be cosmetically acceptable, some cases warrant consideration of reconstructive options, and while several reconstructive options have been described in this role, a series of deep inferior epigastric perforator (DIEP) flaps has not been reported to date.

Methods:

A cohort of 18 patients undergoing PMD reconstruction with a DIEP flap were included. Patient‐specific data, operation details, cosmetic results, and complication rates were assessed. Oncologic outcomes, in particular recurrence rates, were also evaluated.

Results:

In our series there were no cases of partial or total flap necrosis, and overall complications were low. There were two cases of wound infection (both had undergone radiotherapy), managed conservatively, and one case of reoperation due to hematoma. There were no cancer recurrences or effect on oncologic management. Cosmetic outcome was rated as high by both patients and surgeon. The results were thus comparable with other reconstructive options.

Conclusion:

Although autologous reconstruction has an established complication rate, our results suggest that the DIEP flap may be of considerable value for delayed reconstruction of selected larger partial mastectomy defects. © 2010 Wiley‐Liss, Inc. Microsurgery, 2011.
Soy isoflavone genistein induces cell death in breast cancer cells through mobilization of endogenous copper ions and generation of reactive oxygen species
Authors: Ullah Mohammad F. , Ahmad Aamir , Zubair Haseeb , Khan Husain Y. , Wang Zhiwei , Sarkar Fazlul H. , Hadi Sheikh M.
Published: December 2010

Scope: Worldwide geographical variation in cancer incidence indicates a correlation between dietary habits and cancer risk. Epidemiological studies have suggested that populations with high isoflavone intake through soy consumption have lower rates of breast, prostate, and colon cancer. Isoflavone genistein in soybean is considered a potent chemopreventive agent against cancer. Although several mechanisms have been proposed, a clear anticancer action mechanism of genistein is still not known.

Methods and results: Here, we show that the cytotoxic action of genistein against breast cancer cells involves mobilization of endogenous copper. Further, whereas the copper specific chelator neocuproine is able to inhibit the apoptotic potential of genistein, the molecules which specifically bind iron (desferroxamine mesylate) and zinc (histidine) are relatively ineffective in causing such inhibition. Also, genistein‐induced apoptosis in these cells is inhibited by scavengers of reactive oxygen species (ROS) implicating ROS as effector elements leading to cell death.

Conclusions: As copper levels are known to be considerably elevated in almost all types of cancers, in this proof‐of‐concept study we show that genistein is able to target endogenous copper leading to prooxidant signaling and consequent cell death. We believe that such a mechanism explains the anticancer effect of genistein as also its preferential cytotoxicity towards cancer cells.
Sanfte Landung schneller lonen
Authors: Räder Hans Joachim , Müllen Klaus
Published: December 2010

Kann man Moleküle analysieren, reinigen und zu kristallinen Schichten verarbeiten, wenn sie sich weder lösen noch verdampfen lassen? Eigentlich nicht – es sei denn, man findet eine neue Methode: „MALDI‐Soft‐Landing”︁. Über die Handhabung von Molekülen hinaus hat das Verfahren auch Potential zum Aufbau organischer Halbleiterstrukturen.
Redoxpolymerisation und Superabsorber – Werner Kern (1906 – 1985)
Authors: Braun Dietrich
Published: December 2010

Wenn Herrmann Staudinger mit Fug und Recht als Begründer der wissenschaftlichen makromolekularen Chemie gilt, dann hat sein Schüler Werner Kern in präparativen Arbeiten die makromolekulare Chemie aus ihrer Isolierung innerhalb der organischen Chemie herausgeführt. Dieses Jahr hätte Kern seinen 100. Geburtstag gefeiert.