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Sample records for hyaluronan receptor lyve-1

  1. The interaction between LYVE-1 with hyaluronan on the cell surface may play a role in the diversity of adhesion to cancer cells.

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    Yan Du

    Full Text Available Hyaluronan (HA, a simple disaccharide unit, can polymerize and is considered a primary component of the extracellular matrix, which has a wide range of biological functions. In recent years, HA was found on the surface of tumor cells. According to previous reports, differing HA content on the cell surface of tumor cells is closely related to lymph node metastases, but the mechanisms mediating this process remained unclear. This research intended to study the surface content of HA on tumor cells and analyze cell adhesive changes caused by the interaction between HA and its lymphatic endothelial receptor (LYVE-1. We screened and observed high HA content on HS-578T breast cells and low HA content on MCF-7 breast cells through particle exclusion, immunofluorescence and flow cytometry experiments. The expression of LYVE-1, the lymph-vessel specific HA receptor, was consistent with our previous report and enhanced the adhesion of HA(high-HS-578T cells to COS-7(LYVE-1(+ through HA in cell static adhesion and dynamic parallel plate flow chamber experiments. MCF-7 breast cells contain little HA on the surface; however, our results showed little adhesion difference between MCF-7 cells and COS-7(LYVE-1(+ and COS-7(LYVE-1(- cells. Similar results were observed concerning the adhesion of HS-578T cells or MCF-7 cells to SVEC4-10 cells. Furthermore, we observed for the first time that the cell surface HA content of high transfer tumor cells was rich, and we visualized the cross-linking of HA cable structures, which may activate LYVE-1 on lymphatic endothelial cells, promoting tumor adhesion. In summary, high-low cell surface HA content of tumor cells through the interaction with LYVE-1 leads to adhesion differences.

  2. Relationship between LYVE-1, VEGFR-3 and CD44 gene expressions and lymphatic metastasis in gastric cancer

    Institute of Scientific and Technical Information of China (English)

    FusunOzmen; MahirOzmen; EvrenOzdemir; MunevverMoran; SeldaSeckin; DicleGUC; ErgunKaraagaoglu; EminKansu

    2011-01-01

    AIM: To investigate the expression levels of lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1), vascular endothelial growth factor receptor-3 (VEGFR-3) and CD44 genes and the relationship between their levels and clinicopathological parameters in gastric cancer.METHODS: Tissue samples were obtained from 33 patients (8 females) with gastric cancer. mRNA levels of LYVE-1, VEGFR-3 and CD44 in normal and tumor tissues were quantitatively measured using real time polymerase chain reaction. The results were correlated with lymph node metastasis, histological type and differentiation of the tumor, T-stage, and presence of vascular, perineural and lymphatic invasions. The distribution of molecules in the tissue was evaluated using immunohistochemistry. RESULTS: LYVE-1, CD44 and VEGFR-3 gene expression levels were significantly higher in gastric cancer than in normal tissue. While there was no correlation between gene expressions and clinicopathologic fea- tures such as histologic type, differentiation and stage, gene expression levels were found to be increased in conjunction with positive lymph node/total lymph node ratio and the presence of perineural invasion. A significant correlation was also found between LYVE-1 and CD44 over-expressions and perineural invasion and lymph node positivity in gastric cancers. When the dis- tribution of LYVE-1 antibody-stained lymphatic vessels in tissue was evaluated, lymphatic vessels were located intra-tumorally in 13% and peri-tumorally in 27% of the patients. Moreover, lymph node metastases were also positive in all patients with LYVE-1-staining. CONCLUSION: LYVE-1, VEGFR-3 and CD44 all play an important role in lymphangiogenesis, invasion and metastasis. LYVE-1 is a perfectly reliable lymphatic vessel marker and useful for immunohistochemistry.

  3. Mouse lymphatic endothelial cell targeted probes: anti-LYVE-1 antibody-based magnetic nanoparticles

    Directory of Open Access Journals (Sweden)

    Guo Q

    2013-06-01

    Full Text Available Qiu Guo,1,2,* Yi Liu,1,* Ke Xu,1 Ke Ren,1 WenGe Sun1 1Department of Radiology, The First Hospital of China Medical University, Shenyang, Liaoning, People's Republic of China; 2Key Laboratory of Imaging Diagnosis and Interventional Radiology of Liaoning Province, Shenyang, Liaoning, People's Republic of China *These authors contributed equally to this work Purpose: To investigate the specific targeting property of lymphatic vessel endothelial hyaluronan receptor-1 binding polyethylene glycol-coated ultrasmall superparamagnetic iron oxide (LYVE-1-PEG-USPIO nanoparticles to mouse lymphatic endothelial cells (MLECs. Methods: A ligand specific target to lymphatic vessels was selected by immunohistochemical staining on the sections of a Lewis subcutaneous transplanted tumor. The z-average hydrodynamic diameter (HD, zeta potential, and the relaxivity of PEG-USPIO and LYVE-1-PEG-USPIO nanoparticles were determined with a laser particle analyzer and magnetic resonance T2 spin echo sequence, respectively. Prussian blue staining and transmission electron microscopy (TEM of nanoparticle labeled cells were performed to determine the nanoparticles' binding form. Magnetic resonance imaging (MRI was performed in vitro to evaluate the signal enhancement on the T2 spin echo sequence of the nanoparticle labeled cells. The iron content of the labeled cells after the Prussian blue staining and MRI scanning was determined by atomic absorption spectroscopy (AAS. Results: The anti-LYVE-1 antibody was used as the specific ligand to synthesize the target probe to the MLECs. The mean z-average HDs of the LYVE-1-PEG-USPIO and PEG-USPIO nanoparticles were 57.42 ± 0.31 nm and 47.91 ± 0.73 nm, respectively, and the mean zeta potentials of the LYVE-1-PEG-USPIO and PEG-USPIO nanoparticles were 12.38 ± 4.87 mV and 2.57 ± 0.83 mV, respectively. The relaxivities of the LYVE-1-PEG-USPIO and PEG-USPIO nanoparticles were 185.48 mM-1s-1 and 608.32 mM-1s-1. Cells binding

  4. Effects of Melatonin, Aluminum Oxide, and Polymethylsiloxane Complex on the Expression of LYVE-1 in the Liver of Mice with Obesity and Type 2 Diabetes Mellitus.

    Science.gov (United States)

    Michurina, S V; Ishchenko, I Yu; Arkhipov, S A; Klimontov, V V; Rachkovskaya, L N; Konenkov, V I; Zavyalov, E L

    2016-12-01

    The effects of melatonin, aluminum oxide, and polymethylsiloxane complex on the expression of LYVE-1 (lymphatic vessel endothelial hyaluronan receptor) in the liver were studied in db/db mice with experimental obesity and type 2 diabetes mellitus. The complex or placebo was administered daily by gavage from week 8 to week 16 of life. The animals receiving the complex exhibited enhanced, in comparison with the placebo group, immunohistochemical LYVE-1+ staining of endothelial cells in sinusoids. Enhanced expression of LYVE-1 was associated with less pronounced dilatation of interlobular arteries, veins, and lymphatic vessels. Thee findings suggest a protective effect of the complex towards structural changes in the liver of mice with obesity and type 2 diabetes.

  5. CD147: regulator of hyaluronan signaling in invasiveness and chemoresistance.

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    Grass, G Daniel; Dai, Lu; Qin, Zhiqiang; Parsons, Chris; Toole, Bryan P

    2014-01-01

    Major determinants that influence negative outcome in cancer patients are the abilities of cancer cells to resist current therapies and to invade surrounding host tissue, consequently leading to local and metastatic dissemination. Hyaluronan (HA), a prominent constituent of the tumor microenvironment, not only provides structural support but also interacts with cell surface receptors, especially CD44, that influence cooperative signaling pathways leading to chemoresistance and invasiveness. CD147 (emmprin; basigin) is a member of the Ig superfamily that has also been strongly implicated in chemoresistance and invasiveness. CD147 both regulates HA synthesis and interacts with the HA receptors, CD44, and LYVE-1. Increased CD147 expression induces formation of multiprotein complexes containing CD44 (or LYVE-1) as well as members of the membrane-type matrix metalloproteinase, receptor tyrosine kinase, ABC drug transporter, or monocarboxylate transporter families, which become assembled in specialized lipid raft domains along with CD147 itself. In each case, multivalent HA-receptor interactions are essential for formation or stabilization of the lipid raft complexes and for downstream signaling pathways or transporter activities that are driven by these complexes. We conclude that cooperativity between HA, HA receptors, and CD147 may be a major driver of the interconnected pathways of invasiveness and chemoresistance widely critical to malignancy.

  6. Expression of hyaluronan synthases and corresponding hyaluronan receptors is differentially regulated during oocyte maturation in cattle.

    Science.gov (United States)

    Schoenfelder, Martin; Einspanier, Ralf

    2003-07-01

    In response to the gonadotropin surge, the compact cumulus-oocyte complex (COC) undergoes expansion by synthesis of the mucopolysaccharide hyaluronan (HA) accompanying oocyte maturation. The objective of the present study was to quantify mRNA transcripts of the HA synthase (HAS) 1, HAS2, and HAS3 and the HA-receptors CD44 and RHAMM (receptor for HA-mediated motility). Additionally, we determined the histological localization of HA and its receptor, CD44, in maturing bovine COCs and cultured granulosa cells (GCs). Full-length transcript of bovine HAS2 and a part of the bovine RHAMM sequence has been made available. Real-time reverse transcriptase-polymerase chain reaction was used for individual mRNA expressions of bovine COCs in comparison to follicular GC gonadotropin treatment. Localization of CD44 and HA were done by immunohistochemistry and biotinylated HA-binding protein, respectively. Gonadotropins caused a rapid, 120-fold increase of HAS2 mRNA, whereas a delayed, 2-fold up-regulation of HAS3 mRNA was observed. The HAS1 transcripts were barely detected. Expression of CD44 mRNA greatly increased during in vitro maturation of COCs, indicating an important role when compared to an unchanged, steady-state RHAMM expression. As a consequence, HA was locally enriched after COC expansion, but only limited change was observed in the GCs. In cultured GCs, HAS2 expression was stimulated through FSH application, followed by the effective treatments of FSH+LH and LH. Treatment with LH induced the highest increase of the CD44 receptor, followed by FSH and FSH+LH treatments. These results suggest that HAS2 is mainly responsible for rapid HA synthesis in bovine COCs and GCs. In bovine COCs, the transcriptional up-regulation of both HAS2 and the receptor CD44 appear to be important prerequisites for initiating HA-mediated effects during final oocyte development and sperm-egg interaction.

  7. Hyaluronan in human malignancies

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    Sironen, R.K. [Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Department of Pathology, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland); Tammi, M.; Tammi, R. [Institute of Biomedicine, Anatomy, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Auvinen, P.K. [Department of Oncology, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland); Anttila, M. [Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Department of Gynecology and Obstetrics, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland); Kosma, V-M., E-mail: Veli-Matti.Kosma@uef.fi [Institute of Clinical Medicine, Pathology and Forensic Medicine, University of Eastern Finland, P.O. Box 1627, FI-70211 Kuopio (Finland); Department of Pathology, Kuopio University Hospital, P.O. Box 1777, FI-70211 Kuopio (Finland)

    2011-02-15

    Hyaluronan, a major macropolysaccharide in the extracellular matrix of connective tissues, is intimately involved in the biology of cancer. Hyaluronan accumulates into the stroma of various human tumors and modulates intracellular signaling pathways, cell proliferation, motility and invasive properties of malignant cells. Experimental and clinicopathological evidence highlights the importance of hyaluronan in tumor growth and metastasis. A high stromal hyaluronan content is associated with poorly differentiated tumors and aggressive clinical behavior in human adenocarcinomas. Instead, the squamous cell carcinomas and malignant melanomas tend to have a reduced hyaluronan content. In addition to the stroma-cancer cell interaction, hyaluronan can influence stromal cell recruitment, tumor angiogenesis and epithelial-mesenchymal transition. Hyaluronan receptors, hyaluronan synthases and hyaluronan degrading enzymes, hyaluronidases, are involved in the modulation of cancer progression, depending on the tumor type. Furthermore, intracellular signaling and angiogenesis are affected by the degradation products of hyaluronan. Hyaluronan has also therapeutic implications since it is involved in multidrug resistance.

  8. Expression of LYVE-1 and Prox-1 in cervical squamous cell carcinoma%淋巴管生成因子LYVE-1及Prox-1在宫颈鳞癌组织的表达及意义

    Institute of Scientific and Technical Information of China (English)

    王健; 盛修贵; 张莉; 张师前; 张廷国

    2011-01-01

    目的:探讨淋巴管生成因子LYVE-1及Prox-1的定量表达与宫颈癌淋巴结转移的相关性.方法:收集宫颈鳞癌手术标本24例,运用半定量RT-PCR技术对淋巴管生成因子LYVE-1和Prox-1进行分析,分别比较这两种因子在切除标本的肿瘤组织、癌旁组织中表达的差异.结果:Prox-1在肿瘤及癌旁组织表达分别为1.52±0.26和0.46±0.19,LYVE-1在肿瘤及癌旁正常组织的表达分别为1.37±0.21和0.56±0.12.Prox-1及LYVE-1在肿瘤组织的表达均高于癌旁组织(P均<0.01),与肿瘤的发生有关.并且它们的表达与淋巴结转移有相关性(P<0.01).结论:Prox-1及LYVE-1表达升高与宫颈癌发生及淋巴结转移有一定关系,检测该指标对了解宫颈癌的侵袭和转移具有一定价值.%Objective: To investigate the relevance between the expression of lymphangiogenesis factor and cervical lymph node metastasis. Method :This study has collected 24 cases of surgical specimens of cervical squamous cell carcinoma-with lymph node metastasis, using semi-quamitatie reverse transcription PCR technique to analyse the expression of lymphangiogenic factor LYVE-1 and Prox-1 , and compared the differential expression of these two factors in tumor and adjacent tissue respectively. Results: The relative expression of Prox-1 in tumor and tissue adjacent to the tumor were I . 52±0. 26 and 0. 46 ±0.19 ( P<0. 01 ) , of LYVE-1 were 1. 37±0. 21 and 0. 56±0. 12 ( P<0. 01 ). They had higher expression m cervical tissues than adjacent tissues,related with the developme.nt of cervical cancer and lymph node metastasis. Conclusion: Prox-1 and LYVE-1 were correlated with cervical cancer and lymph node metastasis,suggesting that detection of LYVE-1 and Prox-1 may be valuable in the evaluation of invasiveness and metastasis of cervical cancer.

  9. Immunohistochemical localization and expression of the hyaluronan receptor CD44 in the epithelium of the pig oviduct during oestrus.

    Science.gov (United States)

    Tienthai, P; Yokoo, M; Kimura, N; Heldin, P; Sato, E; Rodriguez-Martinez, H

    2003-01-01

    Hyaluronan is related to essential reproductive processes in pigs. Hyaluronan produced by cumulus cells builds, via specific cell surface receptors, an extracellular matrix responsible for cumulus cell cloud expansion during final oocyte maturation, a preparatory event for ovulation and fertilization. In addition, hyaluronan that has been localized in the pig oviduct both in the intraluminal fluid and on the surface of the lining epithelium of the preovulatory sperm reservoir, has proven beneficial during in vitro fertilization and embryo culture, thus indicating that it has a role in vivo. This study monitored the immunolocalization, protein determination and gene expression of the major cell surface hyaluronan receptor CD44 in the epithelial lining of the pig oviduct during selected stages of standing oestrus, in relation to spontaneous ovulation. The CD44 immunostaining in the lining epithelium was localized to the surface membrane and the supranuclear domain of mainly the secretory cells, particularly in the sperm reservoir of both treatment (inseminated) and control (non-inseminated) specimens. Up to four hyaluronan-binding protein (HABP) bands (60, 90, 100 and 200 kDa) were detected in the tubal epithelium, and the 200 kDa band was determined as CD44 by immunoblotting. The expression of CD44 mRNA was higher before than after ovulation (P AIJ) of control animals was higher than in those that were inseminated (P AIJ, respectively). The results demonstrate for the first time that the specific hyaluronan receptor CD44 is expressed by the oviduct epithelial cells during spontaneous oestrus, and is particularly abundant in the sperm reservoir before ovulation. Presence of spermatozoa in this segment seemed to downregulate the receptor. The variation in the expression of CD44 in relation to spontaneous ovulation and the presence of spermatozoa indicate that the hyaluronan CD44-signalling pathway may play a role in oviduct function during sperm storage and

  10. LYVE-1及Podoplanin在小鼠Lewis肺癌模型肿瘤内表达情况的初步研究%The Preliminary Study of the Expression of LYVE-1 and Podoplanin in Mouse Modd of Lewis Lung Cancer

    Institute of Scientific and Technical Information of China (English)

    郭秋; 刘屹; 徐克; 任克

    2011-01-01

    目的 检测两种淋巴管标志物LYVE-1及Podoplanin在小鼠Lewis肺癌模型肿瘤中的表达,并比较其表达特异性.方法 建立小鼠Lewis肺癌肿瘤模型,检测LYVE-1、Podoplanin在肿瘤内淋巴管的表达,并利用CD34标记肿瘤内的毛细血管以便与淋巴管进行区分.结果 LYVE-1及Podoplanin染色结果并不完全重叠,Podoplanin阳性表达结果除与LYVE-1相同部分外,尚存在大量棕黄色条带状及阳性细胞结构染色,且CD34表达阴性.结论 LYVE-1较podoplanin对Lewis肺癌淋巴管的识别更为特异,背景更为清晰,与CD34联合应用可准确区分毛细淋巴管与毛细血管.%Objective To investigate the expression of LYVE-1 and Podoplanin in lewis lung cancer and compare the specific expression. Methods Establish mouse model of Lewis lung cancer, use LYVE-1, Podoplanin to detect the expression of lymphatic vessels within the tumor, and use CD34 to distinguish the lymphatic vessels and blood capillaries. Results The staining results of LYVE-1 and podoplanin are not completely identical, except the same part of LYVE-1 .podoplanin was also expressed in other structures which were not the blood vessels verified by CD34. Conclusion LYVE-1 is more specific than podoplanin in identification of lymphatic vessels to the Lewis lung cancer, the background is clearer, and in combination with CD34 can accurately distinguish lymphatic vessels and blood capillary.

  11. Expressions of LYVE-1 and PROX-1 in Breast Carcinoma and Their Clinical Significance%乳腺癌组织中LYVE-1和PROX-1的表达及临床意义

    Institute of Scientific and Technical Information of China (English)

    魏军成; 罗丹枫; 马丁

    2014-01-01

    目的:检测淋巴管内皮细胞透明质酸受体1(LYVE-1)和同源盒基因转录因子1(PROX-1)在人乳腺癌组织中的表达,探讨淋巴管密度在肿瘤淋巴结转移中的临床意义。方法收集80例乳腺浸润性导管癌和35例乳腺良性增生组织,采用免疫组织化学 SP法检测LYVE-1和PROX-1的表达。结果乳腺癌组织中LYVE-1和PROX-1各自标记的淋巴管密度均明显高于乳腺增生组织,差异均有统计学意义(均P<0.01),且与肿瘤淋巴结转移密切相关,有淋巴结转移者均高于无淋巴结转移者(均P<0.01);PROX-1在癌细胞内的表达,不同的肿瘤病理学分级和临床分期之间差异均有统计学意义(均P<0.01)。结论乳腺浸润性导管癌组织中淋巴管生成增多,淋巴管密度与肿瘤淋巴结转移相关, PROX-1可能与乳腺癌发生、发展及淋巴结转移相关。%Objective To investigate the expressions of LYVE-1 and PROX-1 in human breast carcinoma and the clinical significance of lymphatic vessel density.Methods Immunohistochemistry (SP method)was used to detect the expressions of LYVE-1 and PROX-1 in 80 specimens of breast invasive ductal carcinoma and 35 specimens of breast hyperplasia.Results The density of lymphatic vessels positive for LYVE-1 or PROX-1 was significantly higher in breast carcinoma than in breast hyper-plasia (P<0.01).There was a significant correlation between lymphatic vessel density and lymph node metastasis (P<0.01). A negative correlation was noted between the PROX-1 expression in carcinoma cells and tumor grade (P<0.01)or TNM stage (P < 0.01 ).Conclusion Lymphangiogenesis is increased in breast carcinoma,which is associated with lymph node metastasis.PROX-1 may be involved in tumorigenesis,progression and lymphatic metastasis in breast cancer.

  12. Receptor for hyaluronan mediated motility (RHAMM/HMMR) is a novel target for promoting subcutaneous adipogenesis.

    Science.gov (United States)

    Bahrami, S B; Tolg, C; Peart, T; Symonette, C; Veiseh, M; Umoh, J U; Holdsworth, D W; McCarthy, J B; Luyt, L G; Bissell, M J; Yazdani, A; Turley, E A

    2017-03-01

    Hyaluronan, CD44 and the Receptor for Hyaluronan-Mediated Motility (RHAMM, gene name HMMR) regulate stem cell differentiation including mesenchymal progenitor differentiation. Here, we show that CD44 expression is required for subcutaneous adipogenesis, whereas RHAMM expression suppresses this process. We designed RHAMM function blocking peptides to promote subcutaneous adipogenesis as a clinical and tissue engineering tool. Adipogenic RHAMM peptides were identified by screening for their ability to promote adipogenesis in culture assays using rat bone marrow mesenchymal stem cells, mouse pre-adipocyte cell lines and primary human subcutaneous pre-adipocytes. Oil red O uptake into fat droplets and adiponectin production were used as biomarkers of adipogenesis. Positive peptides were formulated in either collagen I or hyaluronan (Orthovisc) gels then assessed for their adipogenic potential in vivo following injection into dorsal rat skin and mammary fat pads. Fat content was quantified and characterized using micro CT imaging, morphometry, histology, RT-PCR and ELISA analyses of adipogenic gene expression. Injection of screened peptides increased dorsal back subcutaneous fat pad area (208.3 ± 10.4 mm(2)versus control 84.11 ± 4.2 mm(2); p 5 weeks as detected by micro CT imaging and perilipin 1 mRNA expression. RHAMM expression suppresses while blocking peptides promote expression of PPARγ, C/EBP and their target genes. Blocking RHAMM function by peptide injection or topical application is a novel and minimally invasive method for potentially promoting subcutaneous adipogenesis in lipodystrophic diseases and a complementary tool to subcutaneous fat augmentation techniques.

  13. 乳腺癌淋巴管LYVE-1和PROX-1表达程度与肿瘤淋巴转移的关联性分析%The Correlation Between Expression of LYVE-1 and PROX-1 in Breast Cancer Associated Lymphatic Vessel and Lymphatic Metastases

    Institute of Scientific and Technical Information of China (English)

    唐睿; 赵春英

    2015-01-01

    目的 观察乳腺浸润性导管癌患者肿瘤组织中乳腺癌淋巴管LYVE-1和PROX-1的表达程度与肿瘤淋巴转移的关联性.方法 选择乳腺浸润性导管癌患者90例为实验组,以60例乳腺良性病变患者为对照组,检测实验组患者肿瘤组织LYVE-1和PROX-1的水平,与对照组患者组织的LYVE-1和PROX-1的水平进行比较;将实验组患者按转移、复发情况进行分类,观察LYVE-1和PROX-1表达与肿瘤淋巴转移的关系.结果 实验组患者肿瘤组织的LYVE-1和PROX-1阳性淋巴管密度(LVD)明显高于对照组,实验组患者中有淋巴转移患者的LYVE-1和PROX-1阳性LVD明显高于无淋巴转移患者,差异具有统计学意义(P <0.05);LYVE-1和PROX-1阳性LVD之间无相关性;logistic回归分析,LYVE-1和PROX-1是肿瘤转移的相关因素,对LYVE-1、PROX-1与转移的关系绘制ROC曲线,AUC分别为0.716、0.672;按ROC曲线分析所得诊断临界值进行分组,随访观察一年,LYVE-1、PROX-1阳性LVD升高患者,淋巴转移率较高.结论 乳腺浸润性导管癌患者肿瘤组织LYVE-1和PROX-1表达与淋巴管生成有关,表达程度高的患者更易发生淋巴转移.

  14. Adiponectin promotes hyaluronan synthesis along with increases in hyaluronan synthase 2 transcripts through an AMP-activated protein kinase/peroxisome proliferator-activated receptor-{alpha}-dependent pathway in human dermal fibroblasts

    Energy Technology Data Exchange (ETDEWEB)

    Yamane, Takumi; Kobayashi-Hattori, Kazuo [Department of Nutritional Sciences, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502 (Japan); Oishi, Yuichi, E-mail: y3oishi@nodai.ac.jp [Department of Nutritional Sciences, Faculty of Applied Bioscience, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya-ku, Tokyo 156-8502 (Japan)

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer Adiponectin promotes hyaluronan synthesis along with an increase in HAS2 transcripts. Black-Right-Pointing-Pointer Adiponectin also increases the phosphorylation of AMPK. Black-Right-Pointing-Pointer A pharmacological activator of AMPK increases mRNA levels of PPAR{alpha} and HAS2. Black-Right-Pointing-Pointer Adiponectin-induced HAS2 mRNA expression is blocked by a PPAR{alpha} antagonist. Black-Right-Pointing-Pointer Adiponectin promotes hyaluronan synthesis via an AMPK/PPAR{alpha}-dependent pathway. -- Abstract: Although adipocytokines affect the functions of skin, little information is available on the effect of adiponectin on the skin. In this study, we investigated the effect of adiponectin on hyaluronan synthesis and its regulatory mechanisms in human dermal fibroblasts. Adiponectin promoted hyaluronan synthesis along with an increase in the mRNA levels of hyaluronan synthase 2 (HAS2), which plays a primary role in hyaluronan synthesis. Adiponectin also increased the phosphorylation of AMP-activated protein kinase (AMPK). A pharmacological activator of AMPK, 5-aminoimidazole-4-carboxamide-1{beta}-ribofuranoside (AICAR), increased mRNA levels of peroxisome proliferator-activated receptor-{alpha} (PPAR{alpha}), which enhances the expression of HAS2 mRNA. In addition, AICAR increased the mRNA levels of HAS2. Adiponectin-induced HAS2 mRNA expression was blocked by GW6471, a PPAR{alpha} antagonist, in a concentration-dependent manner. These results show that adiponectin promotes hyaluronan synthesis along with increases in HAS2 transcripts through an AMPK/PPAR{alpha}-dependent pathway in human dermal fibroblasts. Thus, our study suggests that adiponectin may be beneficial for retaining moisture in the skin, anti-inflammatory activity, and the treatment of a variety of cutaneous diseases.

  15. A case of cervical cancer expressed three mRNA variant of Hyaluronan-mediated motility receptor

    Science.gov (United States)

    Villegas-Ruíz, Vanessa; Salcedo, Mauricio; Zentella-Dehesa, Alejandro; de Oca, Edén V Montes; Román-Basaure, Edgar; Mantilla-Morales, Alejandra; Dávila-Borja, Víctor M; Juárez-Méndez, Sergio

    2014-01-01

    Cervical cancer is the second malignancy in Mexico, little is known about the prognostic factors associated with this disease. Several cellular components are important in their transformation and progression. Alternative mRNA splice is an important mechanism for generating protein diversity, nevertheless, in cancer unknown mRNA diversity is expressed. Hyaluronan-mediated motility receptor (HMMR, RHAMM, CD168) is a family member of proteins, hyaluronan acid dependent, and has been associated with different malignant processes such as: angiogenesis, cell invasiveness, proliferation, metastasis and poor outcome in some tumors. In the present study we identified expression of HMMR in cervical cancer by means of RT-PCR and sequencing. Our results indicate co-expression of two HMMR variants in all samples, and one case expressed three alternative HMMR splice transcripts. These results showed the heterogeneity of mRNA transcripts of HMMR that could express in cancer and the expression of HMMR could be marker of malignancy in CC. PMID:24966934

  16. LYVE-1、Prox-1在非小细胞肺癌中的表达及其与淋巴转移的关系%Expression of LYVE-1 and Prox-1 in Non-small Cell Lung Cancer and the Relationship with Lymph Node Metastasis

    Institute of Scientific and Technical Information of China (English)

    常超; 王平; 杨慧; 李琳; 张利斌

    2011-01-01

    目的 探讨淋巴管内皮透明质酸受体-1(LYVE-1)、同源异型盒转录因子(Prox-1)在非小细胞肺癌(NSCLC)中的表达规律,与微淋巴管密度(MLVD)及淋巴转移之间的关系及其在NSCLC发生发展、预后中的意义.方法 以40例经病理确诊的NSCLC组织(分为肿瘤中心组织及肿瘤周边组织)为实验组,以11例肺良性病变组织为对照组,采用免疫组化法检测上述组织中LYVE-1、Prox-1及CD31蛋白的表达,光镜下计数MLVD及微血管密度.结果 ①NSCLC肿瘤中心组织中LYVE-1及Prox-1标记的MLVD分别为4.22±1.25、1.99±1.49,低于肺良性病变组织(P均为0.000).②NSCLC肿瘤周边组织中LYVE-1及Prox-1标记的MLVD分别为10.89±2.06、6.63±1.99,高于肿瘤中心部位及肺良性病变组织(P均为0.000).③肿瘤周边组织中LYVE-1及Prox-1标记的MLVD与NSCLC患者的性别、年龄、肿瘤的大小、组织学类型、分化程度无关,但在有无肿瘤的淋巴结转移(P=0.000)、PTNM分期的高低间(P=0.000)差异有统计学意义,且随着肿瘤的淋巴结转移、PTNM分期的升高,LYVE-1及Prox-1蛋白的表达量及MLVD增加.而CD31与肿瘤的淋巴结转移、PTNM分期无关.④LYVE-1与Prox-1标记的MLVD相关(r=0.529,P=0.000).LYVE-1、Prox-1标记的MLVD与CD31标记的微血管密度无关.结论 与肿瘤淋巴转移相关的有功能的淋巴管主要位于肿瘤周边部位,而非肿瘤中心部位;LYVE-1与Prox-1可能成为检测NSCLC淋巴转移和评估预后的重要分子指标.

  17. The human and mouse receptors of hyaluronan-mediated motility, RHAMM, genes (HMMR) map to human chromosome 5q33.2-qter and mouse chromosome 11

    Energy Technology Data Exchange (ETDEWEB)

    Spicer, A.P.; McDonald, J.A. [Mayo Clinic Scottsdale, AZ (United States); Roller, M.L.; Camper, S.A. [Univ. of Michigan Medical School, Ann Arbor, MI (United States)] [and others

    1995-11-01

    The gene for the receptor for hyaluronan-mediated motility, RHAAM (designated hyaluronan-mediated motility receptor, HMMR (human) and Hmmr (mouse), for mapping purposes), was localized to human chromosome 5q33.2-qter by somatic cell and radiation hybrid analyses. Investigation of two interspecific back-crosses localized the mouse RHAMM (Hmmr) locus 18 cM from the centromere of mouse chromosome 11 within a region of synteny homology with human chromosome 5q23-q35 genes. The map position of the human RHAMM gene places it in a region comparatively rich in disease-associated genes, including those for low-frequency hearing loss, dominant limb-girdle muscular dystrophy, diastrophic dysplasia, Treacher Collins syndrome, and myeloid disorders associated with the 5q-syndrome. The RHAMM gene location and its ability to transform cells when overexpressed implicate RHAMM as a possible candidate gene in the pathogenesis of the recently described t(5;14)(q33-q34;q11) acute lymphoblastic leukemias. 18 refs., 1 fig.

  18. Critical importance of appropriate fixation conditions for faithful imaging of receptor microclusters

    Directory of Open Access Journals (Sweden)

    Tess A. Stanly

    2016-09-01

    Full Text Available Receptor clustering is known to trigger signalling events that contribute to critical changes in cellular functions. Faithful imaging of such clusters by means of fluorescence microscopy relies on the application of adequate cell fixation methods prior to immunolabelling in order to avoid artefactual redistribution by the antibodies themselves. Previous work has highlighted the inadequacy of fixation with paraformaldehyde (PFA alone for efficient immobilisation of membrane-associated molecules, and the advantages of fixation with PFA in combination with glutaraldehyde (GA. Using fluorescence microscopy, we here highlight how inadequate fixation can lead to the formation of artefactual clustering of receptors in lymphatic endothelial cells, focussing on the transmembrane hyaluronan receptors LYVE-1 and CD44, and the homotypic adhesion molecule CD31, each of which displays their native diffuse surface distribution pattern only when visualised with the right fixation techniques, i.e. PFA/GA in combination. Fluorescence recovery after photobleaching (FRAP confirms that the artefactual receptor clusters are indeed introduced by residual mobility. In contrast, we observed full immobilisation of membrane proteins in cells that were fixed and then subsequently permeabilised, irrespective of whether the fixative was PFA or PFA/GA in combination. Our study underlines the importance of choosing appropriate sample preparation protocols for preserving authentic receptor organisation in advanced fluorescence microscopy.

  19. The ubiquitous hyaluronan: Functionally implicated in the oviduct?

    Science.gov (United States)

    Rodriguez-Martinez, H; Tienthai, P; Atikuzzaman, M; Vicente-Carrillo, A; Rubér, M; Alvarez-Rodriguez, M

    2016-07-01

    Hyaluronan (hyaluronic acid) is a simple, nonantigenic, nonsulfated glycosaminoglycan present everywhere in the extracellular compartments of the body. Noteworthy, it is highly conserved phylogenetically, from sauropsida to mammals; and plays a plethora of roles from embryonic/fetal development to adult physiological and pathological events, including tumor development. In reproduction, hyaluronan has proven related to initial events as sperm survival, buildup of the sperm reservoir in the oviduct, regulation of sperm capacitation, and prefertilization to later participate in embryo, fetal, and placental development. Synthesis, binding (via the CD44 membrane receptor), and degradation of hyaluronan occur in male and female genital organs, the oviduct being no exception. This review discusses our current knowledge on roles of this ubiquitous glycosaminoglycan on the survival of immunologically foreign spermatozoa in the pig oviduct, a relevant event for fertility. During preovulatory storage in the functional tubal sperm reservoir, spermatozoa are entrapped in a mucus-like tubal fluid. This fluid contains fluctuating levels of hyaluronan, which is synthesized by the lining epithelium by hyaluronan synthase 3. Both hyaluronan and its CD44 receptor are particularly evident in the deep mucosal furrows of the sperm reservoir, in which most spermatozoa are embedded in; kept alive, uncapacitated but also undetected by the immune system of the female. Hyaluronan is also present in the seminal plasma, and evidence points toward an involvement of hyaluronan and its receptor in the local (tubal and possibly uterine) production of antiinflammatory cytokines, such as interleukin-10, pertaining maternal immune tolerance of these foreign cells.

  20. Divergent temporal expression of hyaluronan metabolizing enzymes and receptors with craniotomy vs. controlled cortical impact injury in rat brain: A pilot study

    Directory of Open Access Journals (Sweden)

    Guoqiang eXing

    2014-09-01

    Full Text Available Traumatic brain injury triggers many secondary changes in tissue biology which ultimately determine the extent of injury and clinical outcome. Hyaluronan (hyaluronic acid, HA is a protective cementing gel present in the intercellular spaces whose degradation has been reported as a causative factor in tissue damage. Yet little is known about the expression and activities of genes involved in HA catabolism after TBI. Young adult male Sprague-Dawley rats were assigned to three groups: naïve control, craniotomy and, controlled-cortical impact-induced TBI (CCI-TBI. Four animals per group were sacrificed at 4h, 1d, 3d and 7d post CCI. The mRNA expression of hyaluronan synthases (HAS1-3, hyaluronidases (enzymes for HA degradation, HYAL 1-4 & PH20 and CD44 and RHAMM (membrane receptors for HA signaling and removal were determined using real-time PCR. Compared to the naïve controls, expression of HAS1 and HAS2 mRNA, but not HAS3 mRNA increased significantly following craniotomy alone and following CCI with differential kinetics. Expression of HAS2 mRNA increased significantly in the ipsilateral brain at 1d and 3d post CCI. HYAL1 mRNA expression also increased significantly in the craniotomy group and in the contralateral CCI at 1d and 3d post CCI. CD44 mRNA expression increased significantly in the ipsilateral CCI at 4h, 1d, 3d and 7d post CCI (up to 25 fold increase. These data suggest a dynamic regulation and role for HA metabolism in secondary responses to traumatic brain injury.

  1. Production Methods for Hyaluronan

    Directory of Open Access Journals (Sweden)

    Carmen G. Boeriu

    2013-01-01

    Full Text Available Hyaluronan is a polysaccharide with multiple functions in the human body being involved in creating flexible and protective layers in tissues and in many signalling pathways during embryonic development, wound healing, inflammation, and cancer. Hyaluronan is an important component of active pharmaceutical ingredients for treatment of, for example, arthritis and osteoarthritis, and its commercial value far exceeds that of other microbial extracellular polysaccharides. Traditionally hyaluronan is extracted from animal waste which is a well-established process now. However, biotechnological synthesis of biopolymers provides a wealth of new possibilities. Therefore, genetic/metabolic engineering has been applied in the area of tailor-made hyaluronan synthesis. Another approach is the controlled artificial (in vitro synthesis of hyaluronan by enzymes. Advantage of using microbial and enzymatic synthesis for hyaluronan production is the simpler downstream processing and a reduced risk of viral contamination. In this paper an overview of the different methods used to produce hyaluronan is presented. Emphasis is on the advancements made in the field of the synthesis of bioengineered hyaluronan.

  2. Production methods for hyaluronan

    NARCIS (Netherlands)

    Boeriu, C.G.; Springer, J.; Kooy, F.K.; Broek, van den L.A.M.; Eggink, G.

    2013-01-01

    Hyaluronan is a polysaccharide with multiple functions in the human body being involved in creating flexible and protective layers in tissues and in many signalling pathways during embryonic development, wound healing, inflammation, and cancer. Hyaluronan is an important component of active

  3. The where, when, how and why of hyaluronan binding by immune cells

    Directory of Open Access Journals (Sweden)

    Sally S. M. Lee-Sayer

    2015-04-01

    Full Text Available Hyaluronan is made and extruded from cells to form a pericellular or extracellular matrix (ECM and is present in virtually all tissues in the body. The size and form of hyaluronan present in tissues is indicative of a healthy or inflamed tissue, and the interactions of hyaluronan with immune cells can influence their response. Thus in order to understand how inflammation is regulated, it is necessary to understand these interactions and their consequences. Although there is a large turnover of hyaluronan in our bodies, the large molecular mass form of hyaluronan predominates in healthy tissues. Upon tissue damage and/or infection, the ECM and hyaluronan are broken down and an inflammatory response ensues. As inflammation is resolved, the ECM is restored and high molecular mass hyaluronan predominates again. Immune cells encounter hyaluronan in the tissues and lymphoid organs and respond differently to high and low molecular mass forms. Immune cells differ in their ability to bind hyaluronan and this can vary with the cell type and their activation state. For example, peritoneal macrophages do not bind soluble hyaluronan but can be induced to bind after exposure to inflammatory stimuli. Likewise, naïve T cells, which typically express low levels of CD44, the hyaluronan receptor, do not bind hyaluronan until they undergo antigen-stimulated T cell proliferation and upregulate CD44. Despite substantial knowledge of where and when immune cells bind hyaluronan, why immune cells bind hyaluronan remains a major outstanding question. Here, we review what is currently known about the interactions of hyaluronan with immune cells in both healthy and inflamed tissues and discuss how hyaluronan binding by immune cells influences the inflammatory response.

  4. The where, when, how, and why of hyaluronan binding by immune cells.

    Science.gov (United States)

    Lee-Sayer, Sally S M; Dong, Yifei; Arif, Arif A; Olsson, Mia; Brown, Kelly L; Johnson, Pauline

    2015-01-01

    Hyaluronan is made and extruded from cells to form a pericellular or extracellular matrix (ECM) and is present in virtually all tissues in the body. The size and form of hyaluronan present in tissues are indicative of a healthy or inflamed tissue, and the interactions of hyaluronan with immune cells can influence their response. Thus, in order to understand how inflammation is regulated, it is necessary to understand these interactions and their consequences. Although there is a large turnover of hyaluronan in our bodies, the large molecular mass form of hyaluronan predominates in healthy tissues. Upon tissue damage and/or infection, the ECM and hyaluronan are broken down and an inflammatory response ensues. As inflammation is resolved, the ECM is restored, and high molecular mass hyaluronan predominates again. Immune cells encounter hyaluronan in the tissues and lymphoid organs and respond differently to high and low molecular mass forms. Immune cells differ in their ability to bind hyaluronan and this can vary with the cell type and their activation state. For example, peritoneal macrophages do not bind soluble hyaluronan but can be induced to bind after exposure to inflammatory stimuli. Likewise, naïve T cells, which typically express low levels of the hyaluronan receptor, CD44, do not bind hyaluronan until they undergo antigen-stimulated T cell proliferation and upregulate CD44. Despite substantial knowledge of where and when immune cells bind hyaluronan, why immune cells bind hyaluronan remains a major outstanding question. Here, we review what is currently known about the interactions of hyaluronan with immune cells in both healthy and inflamed tissues and discuss how hyaluronan binding by immune cells influences the inflammatory response.

  5. Therapeutic Targeting of Hyaluronan in the Tumor Stroma

    Energy Technology Data Exchange (ETDEWEB)

    Kultti, Anne, E-mail: akultti@halozyme.com [Department of Research, Halozyme Therapeutics, 11388 Sorrento Valley Road, San Diego, CA 92121 (United States); Li, Xiaoming; Jiang, Ping; Thompson, Curtis B. [Department of Pharmacology and Safety Assessment, Halozyme Therapeutics, 11388 Sorrento Valley Road, San Diego, CA 92121 (United States); Frost, Gregory I. [Department of General and Administrative, Halozyme Therapeutics, 11388 Sorrento Valley Road, San Diego, CA 92121 (United States); Shepard, H. Michael [Department of Research, Halozyme Therapeutics, 11388 Sorrento Valley Road, San Diego, CA 92121 (United States)

    2012-09-06

    The tumor stroma, consisting of non-malignant cells and the extracellular matrix, undergoes significant quantitative and qualitative changes throughout malignant transformation and tumor progression. With increasing recognition of the role of the tumor microenvironment in disease progression, stromal components of the tumor have become attractive targets for therapeutic intervention. Stromal accumulation of the glycosaminoglycan hyaluronan occurs in many tumor types and is frequently associated with a negative disease prognosis. Hyaluronan interacts with other extracellular molecules as well as cellular receptors to form a complex interaction network influencing physicochemical properties, signal transduction, and biological behavior of cancer cells. In preclinical animal models, enzymatic removal of hyaluronan is associated with remodeling of the tumor stroma, reduction of tumor interstitial fluid pressure, expansion of tumor blood vessels and facilitated delivery of chemotherapy. This leads to inhibition of tumor growth and increased survival. Current evidence shows that abnormal accumulation of hyaluronan may be an important stromal target for cancer therapy. In this review we highlight the role of hyaluronan and hyaluronan-mediated interactions in cancer, and discuss historical and recent data on hyaluronidase-based therapies and the effect of hyaluronan removal on tumor growth.

  6. Heparan sulfate proteoglycan isoforms of the CD44 hyaluronan receptor induced in human inflammatory macrophages can function as paracrine regulators of fibroblast growth factor action.

    Science.gov (United States)

    Jones, M; Tussey, L; Athanasou, N; Jackson, D G

    2000-03-17

    The CD44 glycoprotein is expressed in multiple isoforms on a variety of cell types where it functions as a receptor for hyaluronan-mediated motility. Recently, interest has centered on CD44 heparan sulfate proteoglycan (HSPG) isoforms because of their potential to sequester heparin-binding growth factors and chemokines. Expression of these isoforms on ectodermal cells has recently been shown to regulate limb morphogenesis via presentation of fibroblast growth factor (FGF) 4/FGF 8 while expression on tumor cells was shown to sequester hepatocyte growth factor and promote tumor dissemination. To date, however, CD44 HSPG expression in tissue macrophages and lymphocytes has not been adequately investigated, despite the fact these cells actively synthesize growth factors and chemokines and indirect evidence that monocyte CD44 sequesters macrophage inflammatory protein-1beta. Here we show primary human monocytes rather than lymphocytes express CD44 HSPGs, but only following in vitro differentiation to macrophages or activation with the proinflammatory cytokine interleukin-1alpha or bacterial lipopolysaccharide. Furthermore, we show these isoforms are preferentially modified with heparan rather than chondroitin sulfate, bind the macrophage-derived growth factors FGF-2, vascular endothelial growth factor, and heparin-binding epidermal growth factor with varying affinities (K(d) 25-330 nM) and in the case of FGF-2, can stimulate productive binding to the high affinity tyrosine kinase FGF receptor 1 (FGFR1). In contrast, we find no evidence for significant binding to C-C chemokines. Last, we confirm by immunofluorescent antibody staining that inflamed synovial membrane macrophages express CD44 HSPGs and that expression is greatest in cells containing high FGF-2 levels. These results suggest a paracrine role for macrophage CD44 HSPG isoforms in the regulation of growth factor action during inflammation.

  7. Developing Fluorescent Hyaluronan Analogs for Hyaluronan Studies

    Directory of Open Access Journals (Sweden)

    Shi Ke

    2012-02-01

    Full Text Available Two kinds of fluorescent hyaluronan (HA analogs, one serving as normal imaging agent and the other used as a biosensitive contrast agent, were developed for the investigation of HA uptake and degradation. Our approach of developing HA imaging agents depends on labeling HA with varying molar percentages of a near-infrared (NIR dye. At low labeling ratios, the hyaluronan uptake can be directly imaged while at high labeling ratios, the fluorescent signal is quenched and signal generation occurs only after degradation. It is found that the conjugate containing 1%–2% NIR dye can be used as a normal optical imaging agent, while bioactivable imaging agents are formed at 6% to 17% dye loading. It was determined that the conjugation of dye to HA with different loading percentages does not impact HA biodegradation by hyaluronidase (Hyal. The feasibility of using these two NIR fluorescent hyaluronan analogs for HA investigation was evaluated in vivo with optical imaging. The data demonstrates that the 1% dye loaded fluorescent HA can be used to monitor the behavior of HA and its fragments, whereas bioactivatable HA imaging agent (17% dye in HA is more suitable for detecting HA fragments.

  8. Biology of hyaluronan: Insights from genetic disorders of hyaluronan metabolism

    Institute of Scientific and Technical Information of China (English)

    Barbara; Triggs-Raine; Marvin; R; Natowicz

    2015-01-01

    Hyaluronan is a rapidly turned over component of the vertebrate extracellular matrix. Its levels are determined, in part, by the hyaluronan synthases, HAS1, HAS2, and HAS3, and three hyaluronidases, HYAL1, HYAL2 and HYAL3. Hyaluronan binding proteins also regulate hyaluronan levels although their involvement is less well understood. To date, two genetic disorders of hyaluronan metabolism have been reported in humans: HYAL1 deficiency(Mucopolysaccharidosis IX) in four individuals with joint pathology as the predominant phenotypic finding and HAS2 deficiency in a single person having cardiac pathology. However, inherited disorders and induced mutations affecting hyaluronan metabolism have been characterized in other species. Overproduction of hyaluronan by HAS2 results in skin folding and thickening in shar-pei dogs and the naked mole rat, whereas a complete deficiency of HAS2 causes embryonic lethality in mice due to cardiac defects. Deficiencies of murine HAS1 and HAS3 result in a predisposition to seizures. Like humans, mice with HYAL1 deficiency exhibit joint pathology. Mice lacking HYAL2 have variably penetrant developmental defects, including skeletal and cardiac anomalies. Thus, based on mutant animal models, a partial deficiency of HAS2 or HYAL2 might be compatible with survival in humans, while complete deficiencies of HAS1, HAS3, and HYAL3 may yet be recognized.

  9. The Content and Size of Hyaluronan in Biological Fluids and Tissues

    Directory of Open Access Journals (Sweden)

    Mary K. Cowman

    2015-06-01

    Full Text Available Hyaluronan is a simple repeating disaccharide polymer, synthesized at the cell surface by integral membrane synthases. The repeating sequence is perfectly homogeneous, and is the same in all vertebrate tissues and fluids. The polymer molecular mass is more variable. Most commonly, hyaluronan is synthesized as a high molecular mass polymer, with an average molecular mass of approximately 1000-8000 kDa. There are a number of studies showing increased hyaluronan content, but reduced average molecular mass with a broader range of sizes present, in tissues or fluids when inflammatory or tissue remodeling processes occur. In parallel studies, exogenous hyaluronan fragments of low molecular mass (generally, less than about 200 kDa have been shown to affect cell behavior through binding to receptor proteins such as CD44 and RHAMM (gene name HMMR, and to signal either directly or indirectly through Toll-like receptors. These data suggest that receptor sensitivity to hyaluronan size provides a biosensor of the state of the microenvironment surrounding the cell. Sensitive methods for isolation and characterization of hyaluronan and its fragments have been developed and continue to improve. This review provides an overview of the methods and our current state of knowledge of hyaluronan content and size distribution in biological fluids and tissues.

  10. Hyaluronan synthase 3 (HAS3) overexpression downregulates MV3 melanoma cell proliferation, migration and adhesion

    Energy Technology Data Exchange (ETDEWEB)

    Takabe, Piia, E-mail: piia.takabe@uef.fi [University of Eastern Finland, Institute of Biomedicine, 70211 Kuopio (Finland); Bart, Geneviève [University of Eastern Finland, Institute of Biomedicine, 70211 Kuopio (Finland); Ropponen, Antti [University of Eastern Finland, Institute of Clinical Medicine, 70211 Kuopio (Finland); Rilla, Kirsi; Tammi, Markku; Tammi, Raija; Pasonen-Seppänen, Sanna [University of Eastern Finland, Institute of Biomedicine, 70211 Kuopio (Finland)

    2015-09-10

    Malignant skin melanoma is one of the most deadly human cancers. Extracellular matrix (ECM) influences the growth of malignant tumors by modulating tumor cells adhesion and migration. Hyaluronan is an essential component of the ECM, and its amount is altered in many tumors, suggesting an important role for hyaluronan in tumorigenesis. Nonetheless its role in melanomagenesis is not understood. In this study we produced a MV3 melanoma cell line with inducible expression of the hyaluronan synthase 3 (HAS3) and studied its effect on the behavior of the melanoma cells. HAS3 overexpression expanded the cell surface hyaluronan coat and decreased melanoma cell adhesion, migration and proliferation by cell cycle arrest at G1/G0. Melanoma cell migration was restored by removal of cell surface hyaluronan by Streptomyces hyaluronidase and by receptor blocking with hyaluronan oligosaccharides, while the effect on cell proliferation was receptor independent. Overexpression of HAS3 decreased ERK1/2 phosphorylation suggesting that inhibition of MAP-kinase signaling was responsible for these suppressive effects on the malignant phenotype of MV3 melanoma cells. - Highlights: • Inducible HAS3-MV3 melanoma cell line was generated using Lentiviral transduction. • HAS3 overexpression inhibits MV3 cell migration via hyaluronan–receptor interaction. • HAS3 overexpression decreases MV3 melanoma cell proliferation and adhesion. • ERK1/2 phosphorylation is downregulated by 50% in HAS3 overexpressing cells. • The results suggest that hyaluronan has anti-cancer like effects in melanoma.

  11. [Larval stages of Ascaris lumbricoides: hyaluronan-binding capacity].

    Science.gov (United States)

    Ponce-León, Patricia; Foresto, Patricia; Valverde, Juana

    2009-03-01

    Hyaluronic acid has important functions in inflammatory and tissue reparation processes. Owing to the varied strategies of the parasites to evade the host's immune response, as well as the multiple functions and physiological importance of hyaluronic acid, the aim was to study the hyaluronan binding capacity by Ascaris lumbricoides larval stages. Larval concentrates were prepared by hatching A. lumbricoides eggs. The larvae were collected by the Baermann method. The test of serum soluble CD44 detection by Agregation Inhibition was modified. All the larval concentrates presented hyaluronan binding capacity. The obtained results allow to suppose the existence of an hyaluronic acid specific receptor in A. lumbricoides. This receptor eventually might compete with the usual receptors of the host. The parasite might use this mechanism to evade the immune response.

  12. Hyaluronan and calcium carbonate hybrid nanoparticles for colorectal cancer chemotherapy

    Science.gov (United States)

    Bai, Jinghui; Xu, Jian; Zhao, Jian; Zhang, Rui

    2017-09-01

    A hybrid drug delivery system (DDS) composed of hyaluronan and calcium carbonate (CC) was developed. By taking advantage of the tumor-targeting ability of hyaluronan and the drug-loading property of CC, the well-formed hyaluronan–CC nanoparticles were able to serve as a DDS targeting colorectal cancer with a decent drug loading content, which is beneficial in the chemotherapy of colorectal cancer. In this study, hyaluronan–CC nanoparticles smaller than 100 nm were successfully developed to load the wide-range anti-cancer drug adriamycin (Adr) to construct hyaluronan–CC/Adr nanoparticles. On the other hand, we also found that hyaluronan–CC/Adr nanoparticles can possibly increase the uptake ratio of Adr into HT29 colorectal cancer cells when compared with hyaluronan-free nanoparticles (CC/Adr) via the CD44 receptor-mediated endocytosis via competitive uptake and in vivo imaging assays. Note that both in vitro (CCK-8 assay on HT29 cells) and in vivo (anti-cancer assay on HT-29 tumor-bearing nude mice model) experiments revealed that hyaluronan–CC/Adr nanoparticles exhibited stronger anti-cancer activity than free Adr or CC/Adr nanoparticles with minimized toxic side effects and preferable cancer-suppression potential.

  13. Hydrocellular foam dressing promotes wound healing along with increases in hyaluronan synthase 3 and PPARα gene expression in epidermis.

    Directory of Open Access Journals (Sweden)

    Takumi Yamane

    Full Text Available BACKGROUND: Hydrocellular foam dressing, modern wound dressing, induces moist wound environment and promotes wound healing: however, the regulatory mechanisms responsible for these effects are poorly understood. This study was aimed to reveal the effect of hydrocellular foam dressing on hyaluronan, which has been shown to have positive effects on wound healing, and examined its regulatory mechanisms in rat skin. METHODOLOGY/PRINCIPAL FINDINGS: We created two full-thickness wounds on the dorsolateral skin of rats. Each wound was covered with either a hydrocellular foam dressing or a film dressing and hyaluronan levels in the periwound skin was measured. We also investigated the mechanism by which the hydrocellular foam dressing regulates hyaluronan production by measuring the gene expression of hyaluronan synthase 3 (Has3, peroxisome proliferator-activated receptor α (PPARα, and CD44. Hydrocellular foam dressing promoted wound healing and upregulated hyaluronan synthesis, along with an increase in the mRNA levels of Has3, which plays a primary role in hyaluronan synthesis in epidermis. In addition, hydrocellular foam dressing enhanced the mRNA levels of PPARα, which upregulates Has3 gene expression, and the major hyaluronan receptor CD44. CONCLUSIONS/SIGNIFICANCE: These findings suggests that hydrocellular foam dressing may be beneficial for wound healing along with increases in hyaluronan synthase 3 and PPARα gene expression in epidermis. We believe that the present study would contribute to the elucidation of the mechanisms underlying the effects of hydrocellular foam dressing-induced moist environment on wound healing and practice evidence-based wound care.

  14. Hyaluronan: from biomimetic to industrial business strategy.

    Science.gov (United States)

    Murano, Erminio; Perin, Danilo; Khan, Riaz; Bergamin, Massimo

    2011-04-01

    Hyaluronan (hyaluronic acid) is a naturally occurring polysaccharide of a linear repeating disaccharide unit consisting of beta-(1-->4)-linked D-glucopyranuronic acid and beta-(1-->3)-linked 2-acetamido-2-deoxy-D-glucopyranose, which is present in extracellular matrices, the synovial fluid of joints, and scaffolding that comprises cartilage. In its mechanism of synthesis, its size, and its physico-chemical properties, hyaluronan is unique amongst other glycosaminoglycans. The network-forming, viscoelastic and its charge characteristics are important to many biochemical properties of living tissues. It is an important pericellular and cell surface constituent; its interaction with other macromolecules such as proteins, participates in regulating cell behavior during numerous morphogenic, restorative, and pathological processes in the body. The knowledge of HA in diseases such as various forms of cancers, arthritis and osteoporosis has led to new impetus in research and development in the preparation of biomaterials for surgical implants and drug conjugates for targeted delivery. A concise and focused review on hyaluronan is timely. This review will cover the following important aspects of hyaluronan: (i) biological functions and synthesis in nature; (ii) current industrial production and potential biosynthetic processes of hyaluronan; (iii) chemical modifications of hyaluronan leading to products of commercial significance; and (iv) and the global market position and manufacturers of hyaluronan.

  15. Hyaluronan in human deciduous tooth germs in the bell stage. Histochemistry and immunohistochemistry

    DEFF Research Database (Denmark)

    Matthiessen, Martin Ebbe; Garbarsch, Charly; Olsen, Birgitte Engelbrecht

    1997-01-01

    Anatomy, development, glycosaminoglycans, hyaluronan, tooth germs, histochemistry, immunocytochemistry......Anatomy, development, glycosaminoglycans, hyaluronan, tooth germs, histochemistry, immunocytochemistry...

  16. Activation of the FGFR-STAT3 pathway in breast cancer cells induces a hyaluronan-rich microenvironment that licenses tumor formation.

    Science.gov (United States)

    Bohrer, Laura R; Chuntova, Pavlina; Bade, Lindsey K; Beadnell, Thomas C; Leon, Ronald P; Brady, Nicholas J; Ryu, Yungil; Goldberg, Jodi E; Schmechel, Stephen C; Koopmeiners, Joseph S; McCarthy, James B; Schwertfeger, Kathryn L

    2014-01-01

    Aberrant activation of fibroblast growth factor receptors (FGFR) contributes to breast cancer growth, progression, and therapeutic resistance. Because of the complex nature of the FGF/FGFR axis, and the numerous effects of FGFR activation on tumor cells and the surrounding microenvironment, the specific mechanisms through which aberrant FGFR activity contributes to breast cancer are not completely understood. We show here that FGFR activation induces accumulation of hyaluronan within the extracellular matrix and that blocking hyaluronan synthesis decreases proliferation, migration, and therapeutic resistance. Furthermore, FGFR-mediated hyaluronan accumulation requires activation of the STAT3 pathway, which regulates expression of hyaluronan synthase 2 (HAS2) and subsequent hyaluronan synthesis. Using a novel in vivo model of FGFR-dependent tumor growth, we demonstrate that STAT3 inhibition decreases both FGFR-driven tumor growth and hyaluronan levels within the tumor. Finally, our results suggest that combinatorial therapies inhibiting both FGFR activity and hyaluronan synthesis is more effective than targeting either pathway alone and may be a relevant therapeutic approach for breast cancers associated with high levels of FGFR activity. In conclusion, these studies indicate a novel targetable mechanism through which FGFR activation in breast cancer cells induces a protumorigenic microenvironment.

  17. Role of hyaluronan and hyaluronan-binding proteins in lung pathobiology.

    Science.gov (United States)

    Lennon, Frances E; Singleton, Patrick A

    2011-08-01

    Hyaluronan (HA) has diverse functions in normal lung homeostasis and pulmonary disease. HA constitutes the major glycosaminoglycan in lung tissue, with HA degradation products, produced by hyaluronidase enzymes and reactive oxygen species, being implicated in several lung diseases, including acute lung injury, asthma, chronic obstructive pulmonary disease, and pulmonary hypertension. The differential activities of HA and its degradation products are due, in part, to regulation of multiple HA-binding proteins, including cluster of differentiation 44 (CD44), Toll-like receptor 4 (TLR4), HA-binding protein 2 (HABP2), and receptor for HA-mediated motility (RHAMM). Recent research indicates that exogenous administration of high-molecular-weight HA can serve as a novel therapeutic intervention for lung diseases, including lipopolysaccharide (LPS)-induced acute lung injury, sepsis/ventilator-induced lung injury, and airway hyperreactivity. This review focuses on the regulatory role of HA and HA-binding proteins in lung pathology and discusses the capacity of HA to augment and inhibit various lung diseases.

  18. Catabolism of hyaluronan: involvement of transition metals

    OpenAIRE

    Šoltés, Ladislav; Kogan, Grigorij

    2009-01-01

    One of the very complex structures in the vertebrates is the joint. The main component of the joint is the synovial fluid with its high-molar-mass glycosaminoglycan hyaluronan, which turnover is approximately twelve hours. Since the synovial fluid does not contain any hyaluronidases, the fast hyaluronan catabolism is caused primarily by reductive-oxidative processes. Eight transition metals – V23, Mn25, Fe26, Co27, Ni28, Cu29, Zn30, and Mo42 – naturally occurring in living organism are essent...

  19. Hyaluronan and phospholipid association in biolubrication

    DEFF Research Database (Denmark)

    Wang, Min; Liu, Chao; Thormann, Esben

    2013-01-01

    load bearing capacity. With DPPC as the last adsorbed component, a friction coefficient of 0.01 was found up to pressures significantly above what is encountered in healthy synovial joints. Hyaluronan as the last added component increases the friction coefficient to 0.03 and decreases the load bearing...... capacity somewhat (but still above what is needed in the synovial joint). Our data demonstrate that self-assembly structures formed by hyaluronan and phospholipids at interfaces are efficient aqueous lubricants, and it seems plausible that such self-assembly structures contribute to the exceptional...

  20. Human Milk Hyaluronan Enhances Innate Defense of the Intestinal Epithelium*

    Science.gov (United States)

    Hill, David R.; Rho, Hyunjin K.; Kessler, Sean P.; Amin, Ripal; Homer, Craig R.; McDonald, Christine; Cowman, Mary K.; de la Motte, Carol A.

    2013-01-01

    Breast-feeding is associated with enhanced protection from gastrointestinal disease in infants, mediated in part by an array of bioactive glycan components in milk that act through molecular mechanisms to inhibit enteric pathogen infection. Human milk contains hyaluronan (HA), a glycosaminoglycan polymer found in virtually all mammalian tissues. We have shown that synthetic HA of a specific size range promotes expression of antimicrobial peptides in intestinal epithelium. We hypothesize that hyaluronan from human milk also enhances innate antimicrobial defense. Here we define the concentration of HA in human milk during the first 6 months postpartum. Importantly, HA isolated from milk has a biological function. Treatment of HT-29 colonic epithelial cells with human milk HA at physiologic concentrations results in time- and dose-dependent induction of the antimicrobial peptide human β-defensin 2 and is abrogated by digestion of milk HA with a specific hyaluronidase. Milk HA induction of human β-defensin 2 expression is also reduced in the presence of a CD44-blocking antibody and is associated with a specific increase in ERK1/2 phosphorylation, suggesting a role for the HA receptor CD44. Furthermore, oral administration of human milk-derived HA to adult, wild-type mice results in induction of the murine Hβ D2 ortholog in intestinal mucosa and is dependent upon both TLR4 and CD44 in vivo. Finally, treatment of cultured colonic epithelial cells with human milk HA enhances resistance to infection by the enteric pathogen Salmonella typhimurium. Together, our observations suggest that maternally provided HA stimulates protective antimicrobial defense in the newborn. PMID:23950179

  1. Human milk hyaluronan enhances innate defense of the intestinal epithelium.

    Science.gov (United States)

    Hill, David R; Rho, Hyunjin K; Kessler, Sean P; Amin, Ripal; Homer, Craig R; McDonald, Christine; Cowman, Mary K; de la Motte, Carol A

    2013-10-04

    Breast-feeding is associated with enhanced protection from gastrointestinal disease in infants, mediated in part by an array of bioactive glycan components in milk that act through molecular mechanisms to inhibit enteric pathogen infection. Human milk contains hyaluronan (HA), a glycosaminoglycan polymer found in virtually all mammalian tissues. We have shown that synthetic HA of a specific size range promotes expression of antimicrobial peptides in intestinal epithelium. We hypothesize that hyaluronan from human milk also enhances innate antimicrobial defense. Here we define the concentration of HA in human milk during the first 6 months postpartum. Importantly, HA isolated from milk has a biological function. Treatment of HT-29 colonic epithelial cells with human milk HA at physiologic concentrations results in time- and dose-dependent induction of the antimicrobial peptide human β-defensin 2 and is abrogated by digestion of milk HA with a specific hyaluronidase. Milk HA induction of human β-defensin 2 expression is also reduced in the presence of a CD44-blocking antibody and is associated with a specific increase in ERK1/2 phosphorylation, suggesting a role for the HA receptor CD44. Furthermore, oral administration of human milk-derived HA to adult, wild-type mice results in induction of the murine Hβ D2 ortholog in intestinal mucosa and is dependent upon both TLR4 and CD44 in vivo. Finally, treatment of cultured colonic epithelial cells with human milk HA enhances resistance to infection by the enteric pathogen Salmonella typhimurium. Together, our observations suggest that maternally provided HA stimulates protective antimicrobial defense in the newborn.

  2. TRPM3 channel stimulated by pregnenolone sulphate in synovial fibroblasts and negatively coupled to hyaluronan

    Directory of Open Access Journals (Sweden)

    English Anne A

    2010-06-01

    Full Text Available Abstract Background Calcium-permeable channels are known to have roles in many mammalian cell types but the expression and contribution of such ion channels in synovial cells is mostly unknown. The objective of this study was to investigate the potential relevance of Transient Receptor Potential Melastatin 3 (TRPM3 channel to fibroblast-like synoviocytes (FLSs of patients with rheumatoid arthritis. Methods The study used RT-PCR and immunofluorescence to detect mRNA and protein. Intracellular calcium measurement detected channel activity in a FLS cell-line and primary cultures of FLSs from patients with rheumatoid arthritis. Enzyme-linked immunosorbent assays measured hyaluronan. Results Endogenous expression of TRPM3 was detected. Previously reported stimulators of TRPM3 sphingosine and pregnenolone sulphate evoked sustained elevation of intracellular calcium in FLSs. The FLS cell-line showed an initial transient response to sphingosine which may be explained by TRPV4 channels but was not observed in FLSs from patients. Blocking antibody targeted to TRPM3 inhibited sustained sphingosine and pregnenolone sulphate responses. Secretion of hyaluronan, which contributes adversely in rheumatoid arthritis, was suppressed by pregnenolone sulphate in FLSs from patients and the effect was blocked by anti-TRPM3 antibody. Conclusions The data suggest that FLSs of patients with rheumatoid arthritis express TRPM3-containing ion channels that couple negatively to hyaluronan secretion and can be stimulated by pharmacological concentrations of pregnenolone sulphate.

  3. Hyaluronan tetrasaccharides stimulate ceramide production through upregulated mRNA expression of ceramide synthesis-associated enzymes.

    Science.gov (United States)

    Kage, Madoka; Tokudome, Yoshihiro

    2016-03-01

    It has been reported that hyaluronan has different physiological functions as suggested by variation in molecular weight. In addition, it has also been reported that CD44, the major hyaluronan receptor, was demonstrated to induce keratinocyte differentiation and lipid synthesis of cholesterol. We focus attention on the hyaluronan tetrasaccharides (HA4) which is the smallest unit of hyaluronan. We previously reported that HA4 induced keratinocyte differentiation and that CD44 may be involved. For the purpose of clarifying the influence of HA4 on ceramide synthesis, we evaluated both of these factors in keratinocytes in vitro and in vivo. The mRNA expression of ceramide synthesis-associated enzymes and intracellular ceramide content were evaluated after HA4 treatment in normal human epidermal keratinocytes. In addition, the ceramide increasing effect of HA4 on skin in UVA-irradiated hairless mice was assessed by water content of stratum corneum (SC) and transepidermal water loss (TEWL) methods. The mRNA expression of ceramide synthesis-associated enzymes and intracellular ceramide content after HA4 treatment were increased compared with the control. Furthermore, HA4 treatment increased water content of SC and decreased TEWL. These findings suggest that HA4 affected ceramide synthesis and is involved in the improvement of UV-induced skin damage.

  4. Brain hyaluronan binding protein inhibits tumor growth

    Institute of Scientific and Technical Information of China (English)

    高锋; 曹曼林; 王蕾

    2004-01-01

    Background Great efforts have been made to search for the angiogenic inhibitors in avascular tissues. Several proteins isolated from cartilage have been proved to have anti-angiogenic or anti-tumour effects. Because cartilage contains a great amount of hyaluronic acid (HA) oligosaccharides and abundant HA binding proteins (HABP), therefore, we speculated that HABP might be one of the factors regulating vascularization in cartilage or anti-angiogenesis in tumours. The purpose of this research was to evaluale the effects of hyaluronan binding protein on inhibiting tumour growth both in vivo and vitro. Methods A unique protein termed human brain hyaluronan (HA) binding protein (b-HABP) was cloned from human brain cDNA library. MDA-435 human breast cancer cell line was chosen as a transfectant. The in vitro underlying mechanisms were investigated by determining the possibilities of MDA-435/b-HABP colony formation on soft agar, the effects of the transfectant on the proliferation of endothelial cells and the expression levels of caspase 3 and FasL from MDA-435/b-HABP. The in vivo study included tumour growth on the chorioallantoic membrane (CAM) of chicken embryos and nude mice. Results Colony formation assay revealed that the colonies formed by MDA-435/b-HABP were greatly reduced compared to mock transfectants. The conditioned media from MDA-435/b-HABP inhibited the growth of endothelial cells in culture. Caspase 3 and FasL expressions were induced by MDA-435/b-HABP. The size of tumours of MDA-435/b-HABP in both CAM and nude mice was much smaller than that of MDA-435 alone. Conclusions Human brain hyaluronan binding protein (b-HABP) may represent a new kind of naturally existing anti-tumour substance. This brain-derived glycoprotein may block tumour growth by inducing apoptosis of cancer cells or by decreasing angiogenesis in tumour tissue via inhibiting proliferation of endothelial cells.

  5. Hyaluronan signaling during ozone-induced lung injury requires TLR4, MyD88, and TIRAP.

    Directory of Open Access Journals (Sweden)

    Zhuowei Li

    Full Text Available Ozone exposure is associated with exacerbation of reactive airways disease. We have previously reported that the damage-associated molecular pattern, hyaluronan, is required for the complete biological response to ambient ozone and that hyaluronan fragments signal through toll-like receptor 4 (TLR4. In this study, we further investigated the role of TLR4 adaptors in ozone-induced airway hyperresponsiveness (AHR and the direct response to hyaluronan fragments (HA. Using a murine model of AHR, C57BL/6J, TLR4-/-, MyD88-/-, and TIRAP-/- mice were characterized for AHR after exposure to either ozone (1 ppm × 3 h or HA fragments. Animals were characterized for AHR with methacholine challenge, cellular inflammation, lung injury, and production of pro-inflammatory cytokines. Ozone-exposed C57BL/6J mice developed cellular inflammation, lung injury, pro-inflammatory cytokines, and AHR, while mice deficient in TLR4, MyD88 or TIRAP demonstrated both reduced AHR and reduced levels of pro-inflammatory cytokines including TNFα, IL-1β, MCP-1, IL-6 and KC. The level of hyaluronan was increased after inhalation of ozone in each strain of mice. Direct challenge of mice to hyaluronan resulted in AHR in C57BL/6J mice, but not in TLR4-/-, MyD88-/-, or TIRAP-/- mice. HA-induced cytokine production in wild-type mice was significantly reduced in TLR4-/-, MyD88-/-, or TIRAP-/- mice. In conclusion, our findings support that ozone-induced airway hyperresponsiveness is dependent on the HA-TLR4-MyD88-TIRAP signaling pathway.

  6. Mannose reduces hyaluronan and leukocytes in wound granulation tissue and inhibits migration and hyaluronan-dependent monocyte binding.

    Science.gov (United States)

    Jokela, Tiina A; Kuokkanen, Jukka; Kärnä, Riikka; Pasonen-Seppänen, Sanna; Rilla, Kirsi; Kössi, Jyrki; Laato, Matti; Tammi, Raija H; Tammi, Markku I

    2013-01-01

    Wound healing is a highly regulated process starting from coagulation and ending in tissue remodeling. The end result varies from perfectly restored tissue, such as in early fetal skin, to scars in adults. The balanced repair process is frequently disturbed by local or systemic factors, like infections and diabetes. A rapid increase of hyaluronan is an inherent feature of wounds and is associated with tissue swelling, epithelial and mesenchymal cell migration and proliferation, and induction of cytokine signaling. Hyaluronan extending from cell surface into structures called cables can trap leukocytes and platelets and change their functions. All these features of hyaluronan modulate inflammation. The present data show that mannose, a recently described inhibitor of hyaluronan synthesis, inhibits dermal fibroblast invasion and prevents the enhanced leukocyte binding to hyaluronan that takes place in cells treated with an inflammatory mediator interleukin-1β. Mannose also reduced hyaluronan in subcutaneous sponge granulation tissue, a model of skin wound, and suppressed its leukocyte recruitment and tissue growth. Mannose thus seems to suppress wounding-induced inflammation in skin by attenuating hyaluronan synthesis.

  7. Structural profiling and biological performance of phospholipid-hyaluronan functionalized single-walled carbon nanotubes

    DEFF Research Database (Denmark)

    Dvash, Ram; Khatchatouriants, Artium; Solmesky, Leonardo J

    2013-01-01

    In spite of significant insolubility and toxicity, carbon nanotubes (CNTs) erupt into the biomedical research, and create an increasing interest in the field of nanomedicine. Single-walled CNTs (SWCNTs) are highly hydrophobic and have been shown to be toxic while systemically administrated. Thus......, SWCNTs have to be functionalized to render water solubility and biocompatibility. Herein, we introduce a method for functionalizing SWCNT using phospholipids (PL) conjugated to hyaluronan (HA), a hydrophilic glycosaminoglycan, with known receptors on many types of cancer and immune cells...

  8. Polypeptide Grafted Hyaluronan: Synthesis and Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaojun [ORNL; Messman, Jamie M [ORNL; Mays, Jimmy [ORNL; Baskaran, Durairaj [University of Tennessee, Knoxville (UTK)

    2010-01-01

    Poly(L-leucine) grafted hyaluronan (HA-g-PLeu) has been synthesized via a Michael addition reaction between primary amine terminated poly(L-leucine) and acrylate-functionalized HA (TBAHA-acrylate). The precursor hyaluronan was first functionalized with acrylate groups by reaction with acryloyl chloride in the presence of triethylamine in N,N-dimethylformamide. 1H NMR analysis of the resulting product indicated that an increase in the concentration of acryloylchoride with respect to hydroxyl groups on HA has only a moderate effect on functionalization efficiency, f. A precise control of stoichiometry was not achieved, which could be attributed to partial solubility of intermolecular aggregates and the hygroscopic nature of HA. Michael addition at high [PLeu- NH2]/[acrylate]TBAHA ratios gave a molar grafting ratio of only 0.20 with respect to the repeat unit of HA, indicating grafting limitation due to insolubility of the grafted HA-g-PLeu. Soluble HA-g-PLeu graft copolymers were obtained for low grafting ratios (<0.039) with <8.6% by mass of PLeu and were characterized thoroughly using light scattering, 1H NMR, FT-IR, and AFM techniques. Light scattering experiments showed a strong hydrophobic interaction between PLeu chains, resulting in aggregates with segregated nongrafted HA segments. This yields local networks of aggregates, as demonstrated by atomic force microscopy. Circular dichroism spectroscopy showed a -sheet conformation for aggregates of poly(L-leucine).

  9. Group B Streptococcus Evades Host Immunity by Degrading Hyaluronan.

    Science.gov (United States)

    Kolar, Stacey L; Kyme, Pierre; Tseng, Ching Wen; Soliman, Antoine; Kaplan, Amber; Liang, Jiurong; Nizet, Victor; Jiang, Dianhua; Murali, Ramachandran; Arditi, Moshe; Underhill, David M; Liu, George Y

    2015-12-09

    In response to tissue injury, hyaluronan (HA) polymers are cleaved by host hyaluronidases, generating small fragments that ligate Toll-like receptors (TLRs) to elicit inflammatory responses. Pathogenic bacteria such as group B Streptococcus (GBS) express and secrete hyaluronidases as a mechanism for tissue invasion, but it is not known how this activity relates to immune detection of HA. We found that bacterial hyaluronidases secreted by GBS and other Gram-positive pathogens degrade pro-inflammatory HA fragments to their component disaccharides. In addition, HA disaccharides block TLR2/4 signaling elicited by both host-derived HA fragments and other TLR2/4 ligands, including lipopolysaccharide. Application of GBS hyaluronidase or HA disaccharides reduced pulmonary pathology and pro-inflammatory cytokine levels in an acute lung injury model. We conclude that breakdown of host-generated pro-inflammatory HA fragments to disaccharides allows bacterial pathogens to evade immune detection and could be exploited as a strategy to treat inflammatory diseases.

  10. Carcinoma Cell Hyaluronan as a "Portable" Cancerized Prometastatic Microenvironment.

    Science.gov (United States)

    Turley, Eva A; Wood, David K; McCarthy, James B

    2016-05-01

    Hyaluronan (HA) is a structurally simple polysaccharide, but its ability to act as a template for organizing pericellular matrices and its regulated synthesis and degradation are key to initiating repair responses. Importantly, these HA functions are usurped by tumor cells to facilitate progression and metastasis. Recent advances have identified the functional complexities associated with the synthesis and degradation of HA-rich matrices. Three enzymes synthesize large HA polymers while multiple hyaluronidases or tissue free radicals degrade these into smaller bioactive fragments. A family of extracellular and cell-associated HA-binding proteins/receptors translates the bioinformation encrypted in this complex polymer mixture to activate signaling networks required for cell survival, proliferation, and migration in an actively remodeling microenvironment. Changes in HA metabolism within both the peritumor stroma and parenchyma are linked to tumor initiation, progression, and poor clinical outcome. We review evidence that metastatic tumor cells must acquire the capability to autonomously synthesize, assemble, and process their own "portable" HA-rich microenvironments to survive in the circulation, metastasize to ectopic sites, and escape therapeutic intervention. Strategies to disrupt the HA machinery of primary tumor and circulating tumor cells may enhance the effectiveness of current conventional and targeted therapies. Cancer Res; 76(9); 2507-12. ©2016 AACR.

  11. Hyaluronan-Based Therapy for Metastatic Prostate Cancer

    Science.gov (United States)

    2015-07-01

    interplay between the extrinsic and intrinsic apoptotic pathways would be an effective rationale for cancer therapy . In reality , however, dulanermin...AWARD NUMBER: W81XWH-14-1-0184 TITLE: Hyaluronan-Based Therapy for Metastatic Prostate Cancer PRINCIPAL INVESTIGATOR: Dr. Magdelena...5a. CONTRACT NUMBER W81XWH-14-1-0184 Hyaluronan-Based Therapy for Metastatic Prostate Cancer 5b. GRANT NUMBER W81XWH-14-1-0184 5c. PROGRAM

  12. Hyaluronan Benzyl Ester as a Scaffold for Tissue Engineering

    OpenAIRE

    2009-01-01

    Tissue engineering is a multidisciplinary field focused on in vitro reconstruction of mammalian tissues. In order to allow a similar three-dimensional organization of in vitro cultured cells, biocompatible scaffolds are needed. This need has provided immense momentum for research on “smart scaffolds” for use in cell culture. One of the most promising materials for tissue engineering and regenerative medicine is a hyaluronan derivative: a benzyl ester of hyaluronan (HYAFF®). HYAFF® can be proc...

  13. Interactions between CD44 and hyaluronan in leukocyte trafficking

    Directory of Open Access Journals (Sweden)

    Braedon eMcDonald

    2015-02-01

    Full Text Available Recruitment of leukocytes from the bloodstream to inflamed tissues requires a carefully regulated cascade of binding interactions between adhesion molecules on leukocytes and endothelial cells. Adhesive interactions between CD44 and hyaluronan have been implicated in the regulation of immune cell trafficking within various tissues. In this review, the biology of CD44-hyaluronan interactions in cell trafficking is summarized, with special attention to neutrophil recruitment within the liver microcirculation. We describe the molecular mechanisms that regulate adhesion between neutrophil CD44 and endothelial hyaluronan, including recent evidence implicating serum-derived hyaluronan associated protein (SHAP as an important co-factor in the binding of hyaluronan to CD44 under flow conditions. CD44-hyaluronan mediated neutrophil recruitment has been shown to contribute to innate immune responses to invading microbes, as well as to the pathogenesis of many inflammatory diseases, including various liver pathologies. As a result, blockade of neutrophil recruitment by targeting CD44-HA interactions has proven beneficial as an anti-inflammatory treatment strategy in a number of animal models of inflammatory diseases.

  14. Cytokines and Growth Factors Stimulate Hyaluronan Production: Role of Hyaluronan in Epithelial to Mesenchymal-Like Transition in Non-Small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Geraldine Chow

    2010-01-01

    Full Text Available In this study, we investigated the role of hyaluronan (HA in non-small cell lung cancer (NSCLC since close association between HA level and malignancy has been reported. HA is an abundant extracellular matrix component and its synthesis is regulated by growth factors and cytokines that include epidermal growth factor (EGF and interleukin-1β (IL-1β. We showed that treatment with recombinant EGF and IL-1β, alone or in combination with TGF-β, was able to stimulate HA production in lung adenocarcinoma cell line A549. TGF-β/IL-1β treatment induced epithelial to mesenchymal-like phenotype transition (EMT, changing cell morphology and expression of vimentin and E-cadherin. We also overexpressed hyaluronan synthase-3 (HAS3 in epithelial lung adenocarcinoma cell line H358, resulting in induced HA expression, EMT phenotype, enhanced MMP9 and MMP2 activities and increased invasion. Furthermore, adding exogenous HA to A549 cells and inducing HA H358 cells resulted in increased resistance to epidermal growth factor receptor (EGFR inhibitor, Iressa. Together, these results suggest that elevated HA production is able to induce EMT and increase resistance to Iressa in NSCLC. Therefore, regulation of HA level in NSCLC may be a new target for therapeutic intervention.

  15. Hyaluronan-lecithin foils and their properties

    Energy Technology Data Exchange (ETDEWEB)

    BiaIopiotrowicz, Tomasz [Department of Interfacial Phenomena, Faculty of Chemistry, Maria Curie-SkIodowska University, Maria Curie-SkIodowska Square 3, 20-031 Lublin (Poland); Janczuk, BronisIaw [Department of Interfacial Phenomena, Faculty of Chemistry, Maria Curie-SkIodowska University, Maria Curie-SkIodowska Square 3, 20-031 Lublin (Poland); Fiedorowicz, Maciej [Department of Chemistry, Agricultural University of Krakow, Mickiewicz Ave., 21, 31 120 Cracow (Poland); Khachatryan, Gohar [Department of Chemistry, Agricultural University of Krakow, Mickiewicz Ave., 21, 31 120 Cracow (Poland); Tomasik, Piotr [Department of Chemistry, Agricultural University of Krakow, Mickiewicz Ave., 21, 31 120 Cracow (Poland)]. E-mail: rrtomasi@cyf-kr.edu.pl; Bakos, Dusan [Faculty of Chemical and Food Technology, Slovak Technical University, Radlinskeho 9, 812 37 Bratislava (Slovakia)

    2006-01-10

    Thin, elastic foils of good resistance to the air exposure, patented as wound healing aids, were prepared by evaporation of a blend of lecithin (L) and sodium hyaluronan (H) taken under varying proportions. The contact angle for water, glycerol, formamide, ethylene glycol and diiodomethane, was determined for these foils. The contact angle was correlated against the H:L foil composition. For all liquids but formamide the highest contact angle was noted for the H:L = 2:1 (g g{sup -1}) ratio. The contact angles provided estimation of the work of adhesion. At the same L:H ratio the work of adhesion was the lowest. It was suggested that lecithin cross-linked hyaluronan. Since the work of adhesion of the studied liquids was similar to that of diiodomethane, it could be concluded that almost all functional groups on the foil surface were completely blocked. Perhaps, at H:L = 2:1 (g g{sup -1}) a stoichiometric complex of hyaluronic acid with lecithin was formed, and polar functional groups from both reagents were involved. Foils seem to be electrostatic complexes of H with L. Foils with the H:L equal to 2:1 exhibited specific properties confirmed by the IR reflectance spectra of the foils. The thermogravimetry (TG/DTG) also revealed unique thermal behaviour confirming other specific properties of the foil of this composition. For the same ratio a thorough inspection of the scanning electron micrographs (SEM) revealed few irregularly distributed perforations of 1-2 {mu}m in diameter seen as black points, which can be recognized as pores. Properties of the foils determined in the contact angle measurements are nicely backed by the results from thermogravimetric and scanning electron microscopic studies.

  16. Pulmonary surfactant adsorption is increased by hyaluronan or polyethylene glycol.

    Science.gov (United States)

    Taeusch, H William; Dybbro, Eric; Lu, Karen W

    2008-04-01

    In acute lung injuries, inactivating agents may interfere with transfer (adsorption) of pulmonary surfactants to the interface between air and the aqueous layer that coats the interior of alveoli. Some ionic and nonionic polymers reduce surfactant inactivation in vitro and in vivo. In this study, we tested directly whether an ionic polymer, hyaluronan, or a nonionic polymer, polyethylene glycol, enhanced adsorption of a surfactant used clinically. We used three different methods of measuring adsorption in vitro: a modified pulsating bubble surfactometer; a King/Clements device; and a spreading trough. In addition we measured the effects of both polymers on surfactant turbidity, using this assay as a nonspecific index of aggregation. We found that both hyaluronan and polyethylene glycol significantly increased the rate and degree of surfactant material adsorbed to the surface in all three assays. Hyaluronan was effective in lower concentrations (20-fold) than polyethylene glycol and, unlike polyethylene glycol, hyaluronan did not increase apparent aggregation of surfactant. Surfactant adsorption in the presence of serum was also enhanced by both polymers regardless of whether hyaluronan or polyethylene glycol was included with serum in the subphase or added to the surfactant applied to the surface. Therefore, endogenous polymers in the alveolar subphase, or exogenous polymers added to surfactant used as therapy, may both be important for reducing inactivation of surfactant that occurs with various lung injuries.

  17. Endothelial protein C receptor-expressing hematopoietic stem cells reside in the perisinusoidal niche in fetal liver.

    Science.gov (United States)

    Iwasaki, Hiroko; Arai, Fumio; Kubota, Yoshiaki; Dahl, Maria; Suda, Toshio

    2010-07-29

    Hematopoietic stem cells (HSCs) are maintained in specialized niches in adult bone marrow. However, niche and HSC maintenance mechanism in fetal liver (FL) still remains unclear. Here, we investigated the niche and the molecular mechanism of HSC maintenance in mouse FL using HSCs expressing endothelial protein C receptor (EPCR). The antiapoptotic effect of activated protein C (APC) on EPCR(+) HSCs and the expression of protease-activated receptor 1 (Par-1) mRNA in these cells suggested the involvement of the cytoprotective APC/EPCR/Par-1 pathway in HSC maintenance. Immunohistochemistry revealed that EPCR(+) cells were localized adjacent to, or integrated in, the Lyve-1(+) sinusoidal network, where APC and extracellular matrix (ECM) are abundant, suggesting that HSCs in FL were maintained in the APC- and ECM-rich perisinusoidal niche. EPCR(+) HSCs were in a relatively slow cycling state, consistent with their high expression levels of p57 and p18. Furthermore, the long-term reconstitution activity of EPCR(+) HSCs decreased significantly after short culture but not when cocultured with feeder layer of FL-derived Lyve-1(+) cells, which suggests that the maintenance of the self-renewal activity of FL HSCs largely depended on the interaction with the perisinusoidal niche. In conclusion, EPCR(+) HSCs resided in the perisinusoidal niche in mouse FL.

  18. Influence of Heating on the Structure of Hyaluronan

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Hyaluronan may be used in tissue engineering as a scaffold, and since the scaffold should degrade after the cells have proliiferated, and heat treatment is a method to achieve low molecular weight material.In this essay, we developed a new method to choose the characteristic heat treatment temperature, and applied a simple method to prepare the hyaluronan scaffold. We have acquired the TG and DTA curves of hyaluronan by thermal analysis, according to which we selected 310 ℃ ,375 ℃ and 500 ℃ as the heat treatment points. After heat treatment, test the infrared spectrum of the powder respectively. In conclusion, the scaffold formed by lyophilization exhibits a porous structure, and the occurrence of new groups after heating assumes the change of the molecular chain.

  19. Rheology of mixed alginate-hyaluronan aqueous solutions.

    Science.gov (United States)

    Travan, Andrea; Fiorentino, Simona; Grassi, Mario; Borgogna, Massimiliano; Marsich, Eleonora; Paoletti, Sergio; Donati, Ivan

    2015-01-01

    The present manuscript addresses the description of binary systems of hyaluronan (HA) and alginate (Alg) in semi-concentrated solution. The two polysaccharides were completely miscible in the entire range of relative weight fraction explored at a total polymer concentration of up to 3% (w/V). The rheological study encompassed steady flow and mechanical spectra for HA/Alg systems at different weight fractions with hyaluronan at different molecular weights. These extensive analyses allowed us to propose a model for the molecular arrangement in solution that envisages a mutual exclusion between the two polysaccharides even though a clear phase separation does not occur. This result may have profound implications when combinations of alginate and hyaluronan are proposed in the field of biomedical materials.

  20. Hyaluronan: A modulator of the tumor microenvironment.

    Science.gov (United States)

    Chanmee, Theerawut; Ontong, Pawared; Itano, Naoki

    2016-05-28

    Tumors are cellular masses formed through dynamic interactions between tumor cells and a mixed population of stromal cells. Crosstalk between oncogenic and adjacent stromal cells contributes to the formation of a "tumor microenvironment" influencing the tumor cell behaviors of proliferation, invasion, and metastatic spread throughout cancer progression. The composition and structure of the tumor microenvironment vary among different types of tumors and are extensively remodeled in close association with tumor advancement. The tumor microenvironment is composed not only of cellular compartments, such as endothelial cells, fibroblasts, inflammatory cells, and immune cells, but also of bioactive substances, including growth factors and the extracellular matrix. Hyaluronan (HA) is a major component of the extracellular matrix, and the degree of HA accumulation is strongly correlated with a poor prognosis in advanced cancer patients. Emerging evidence has suggested that HA creates a specific microenvironment that is favorable for tumor angiogenesis, invasion, and metastasis. This review highlights the prominent roles of HA as a modulator of the tumor microenvironment and addresses the recent advances regarding HA function in cancer stem cell niches. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. Regulated Hyaluronan Synthesis by Vascular Cells

    Directory of Open Access Journals (Sweden)

    Manuela Viola

    2015-01-01

    Full Text Available Cellular microenvironment plays a critical role in several pathologies including atherosclerosis. Hyaluronan (HA content often reflects the progression of this disease in promoting vessel thickening and cell migration. HA synthesis is regulated by several factors, including the phosphorylation of HA synthase 2 (HAS2 and other covalent modifications including ubiquitination and O-GlcNAcylation. Substrate availability is important in HA synthesis control. Specific drugs reducing the UDP precursors are able to reduce HA synthesis whereas the hexosamine biosynthetic pathway (HBP increases the concentration of HA precursor UDP-N-acetylglucosamine (UDP-GlcNAc leading to an increase of HA synthesis. The flux through the HBP in the regulation of HA biosynthesis in human aortic vascular smooth muscle cells (VSMCs was reported as a critical aspect. In fact, inhibiting O-GlcNAcylation reduced HA production whereas increased O-GlcNAcylation augmented HA secretion. Additionally, O-GlcNAcylation regulates HAS2 gene expression resulting in accumulation of its mRNA after induction of O-GlcNAcylation with glucosamine treatments. The oxidized LDLs, the most common molecules related to atherosclerosis outcome and progression, are also able to induce a strong HA synthesis when they are in contact with vascular cells. In this review, we present recent described mechanisms involved in HA synthesis regulation and their role in atherosclerosis outcome and development.

  2. Pathophysiology of the Peritoneal Membrane during Peritoneal Dialysis: The Role of Hyaluronan

    Directory of Open Access Journals (Sweden)

    Susan Yung

    2011-01-01

    Full Text Available During peritoneal dialysis (PD, constant exposure of mesothelial cells to bioincompatible PD solutions results in the denudation of the mesothelial monolayer and impairment of mesothelial cell function. Hyaluronan, a major component of extracellular matrices, is synthesized by mesothelial cells and contributes to remesothelialization, maintenance of cell phenotype, and tissue remodeling and provides structural support to the peritoneal membrane. Chronic peritoneal inflammation is observed in long-term PD patients and is associated with increased hyaluronan synthesis. During inflammation, depolymerization of hyaluronan may occur with the generation of hyaluronan fragments. In contrast to native hyaluronan which offers a protective role to the peritoneum, hyaluronan fragments exacerbate inflammatory and fibrotic processes and therefore assist in the destruction of the tissue. This paper will discuss the contribution of mesothelial cells to peritoneal membrane alterations that are induced by PD and the putative role of hyaluronan in these processes.

  3. XHAPLN3 plays a key role in cardiogenesis by maintaining the hyaluronan matrix around heart anlage.

    Science.gov (United States)

    Ito, Yuzuru; Seno, Satsuki; Nakamura, Hiroaki; Fukui, Akimasa; Asashima, Makoto

    2008-07-01

    Hyaluronan matrix plays an important role during vertebrate cardiogenesis. Transcripts for the hyaluronan synthase Has2 gene are expressed in heart anlage, and disruption of either Has2 or versican, a hyaluronan matrix component, abrogates normal cardiac morphogenesis. However, the mechanisms by which hyaluronan matrix contributes to early heart development are largely unknown. Here we show that Xenopus hyaluronan and proteoglycan-binding link protein 3 (XHAPLN3) helps to maintain hyaluronan matrix around the cardiac anlage, and thereby contribute to cardiogenesis. XHAPLN3 mRNA transcript localization overlapped with the mRNA expression of both Xhas2 and Xversican at the heart anlage of early tailbud (stage 23) embryos. Furthermore, knockdown of XHAPLN3 or Xhas2 with morpholino antisense oligos caused a heart deficiency in developing tadpoles. Our results show when and how components of the hyaluronan matrix function in cardiogenesis, improving our understanding of how extracellular matrix participates in embryogenesis.

  4. Hyaluronan and RHAMM in Wound Repair and the “Cancerization” of Stromal Tissues

    Directory of Open Access Journals (Sweden)

    Cornelia Tolg

    2014-01-01

    Full Text Available Tumors and wounds share many similarities including loss of tissue architecture, cell polarity and cell differentiation, aberrant extracellular matrix (ECM remodeling (Ballard et al., 2006 increased inflammation, angiogenesis, and elevated cell migration and proliferation. Whereas these changes are transient in repairing wounds, tumors do not regain tissue architecture but rather their continued progression is fueled in part by loss of normal tissue structure. As a result tumors are often described as wounds that do not heal. The ECM component hyaluronan (HA and its receptor RHAMM have both been implicated in wound repair and tumor progression. This review highlights the similarities and differences in their roles during these processes and proposes that RHAMM-regulated wound repair functions may contribute to “cancerization” of the tumor microenvironment.

  5. Role of Versican, Hyaluronan and CD44 in Ovarian Cancer Metastasis

    Directory of Open Access Journals (Sweden)

    Miranda P. Ween

    2011-01-01

    Full Text Available There is increasing evidence to suggest that extracellular matrix (ECM components play an active role in tumor progression and are an important determinant for the growth and progression of solid tumors. Tumor cells interfere with the normal programming of ECM biosynthesis and can extensively modify the structure and composition of the matrix. In ovarian cancer alterations in the extracellular environment are critical for tumor initiation and progression and intra-peritoneal dissemination. ECM molecules including versican and hyaluronan (HA which interacts with the HA receptor, CD44, have been shown to play critical roles in ovarian cancer metastasis. This review focuses on versican, HA, and CD44 and their potential as therapeutic targets for ovarian cancer.

  6. Expression of hyaluronan and the hyaluronan-binding proteoglycans neurocan, aggrecan, and versican by neural stem cells and neural cells derived from embryonic stem cells.

    Science.gov (United States)

    Abaskharoun, Mary; Bellemare, Marie; Lau, Elizabeth; Margolis, Richard U

    2010-04-23

    We have examined the expression and localization patterns of hyaluronan and hyaluronan-binding chondroitin sulfate proteoglycans in neural stem cells and differentiated neural cells derived from mouse embryonic stem cells. Expression of proteoglycans and hyaluronan was weak in the SSEA1-positive embryonic stem cells but increased noticeably after retinoic acid induction to nestin-positive neural stem cells. After subsequent plating, the hyaluronan-binding chondroitin sulfate proteoglycans aggrecan, neurocan, and versican are expressed by cells in both the astrocytic and neuronal lineages. During the time period that hyaluronan was present, it co-localized with each of the hyaluronan-binding proteoglycans studied and was found to be clearly associated with beta-III tubulin-expressing neurons and oligodendrocytes expressing the O4 sulfatide marker. Although proteoglycan expression levels increased to varying degrees following neural differentiation, they did not change noticably during the following 2 weeks in culture, but there was a significant decrease in hyaluronan expression. Our studies therefore demonstrate the expression by neural stem cells and neural cells derived from them of hyaluronan and its associated proteoglycans, thereby providing a necessary foundation for integrating their specific properties into developing strategies for therapeutic applications.

  7. The role of hyaluronan in the pathobiology and treatment of respiratory disease.

    Science.gov (United States)

    Garantziotis, Stavros; Brezina, Martin; Castelnuovo, Paolo; Drago, Lorenzo

    2016-05-01

    Hyaluronan, a ubiquitous naturally occurring glycosaminoglycan, is a major component of the extracellular matrix, where it participates in biological processes that include water homeostasis, cell-matrix signaling, tissue healing, inflammation, angiogenesis, and cell proliferation and migration. There are emerging data that hyaluronan and its degradation products have an important role in the pathobiology of the respiratory tract. We review the role of hyaluronan in respiratory diseases and present evidence from published literature and from clinical practice supporting hyaluronan as a novel treatment for respiratory diseases. Preliminary data show that aerosolized exogenous hyaluronan has beneficial activity against airway inflammation, protects against bronchial hyperreactivity and remodeling, and disrupts the biofilm associated with chronic infection. This suggests a role in airway diseases with a predominant inflammatory component such as rhinosinusitis, asthma, chronic obstructive pulmonary disease, cystic fibrosis, and primary ciliary dyskinesia. The potential for hyaluronan to complement conventional therapy will become clearer when data are available from controlled trials in larger patient populations.

  8. Inhibition of Oesophageal Squamous Cell Carcinoma Progression by in vivo Targeting of Hyaluronan Synthesis

    Directory of Open Access Journals (Sweden)

    Savani Rashmin C

    2011-03-01

    Full Text Available Abstract Background Oesophageal cancer is a highly aggressive tumour entity with at present poor prognosis. Therefore, novel treatment options are urgently needed. Hyaluronan (HA is a polysaccharide present in the matrix of human oesophageal squamous cell carcinoma (ESCC. Importantly, in vitro ESCC cells critically depend on HA synthesis to maintain the proliferative phenotype. The aim of the present study is (1 to study HA-synthase (HAS expression and regulation in human ESCC, and (2 to translate the in vitro results into a mouse xenograft model of human ESCC to study the effects of systemic versus tumour targeted HAS inhibition on proliferation and distribution of tumour-bound and stromal hyaluronan. Methods mRNA expression was investigated in human ESCC biopsies by semiquantitative real-time RT PCR. Furthermore, human ESCC were xenografted into NMRI nu/nu mice. The effects on tumour progression and morphology of 4-methylumbelliferone (4-MU, an inhibitor of HA-synthesis, and of lentiviral knock down of HA-synthase 3 (HAS3, the main HAS isoform in the human ESCC tissues and the human ESCC cell line used in this study, were determined. Tumour progression was monitored by calliper measurements and by flat-panel detector volume computed tomography (fpVCT. HA content, cellular composition and proliferation (Ki67 were determined histologically. Results mRNA of HAS isoform 3 (HAS3 was upregulated in human ESCC biopsies and HAS3 mRNA was positively correlated to expression of the epidermal growth factor (EGF receptor. EGF was also proven to be a strong inductor of HAS3 mRNA expression in vitro. During the course of seven weeks, 4-MU inhibited progression of xenograft tumours. Interestingly, remodelling of the tumour into a more differentiated phenotype and inhibition of cell proliferation were observed. Lentiviral knockdown of HAS3 in human ESCC cells prior to xenografting mimicked all effects of 4-MU treatment suggesting that hyaluronan produced by

  9. Therapeutic Targeting of Hyaluronan in the Tumor Stroma

    OpenAIRE

    2012-01-01

    The tumor stroma, consisting of non-malignant cells and the extracellular matrix, undergoes significant quantitative and qualitative changes throughout malignant transformation and tumor progression. With increasing recognition of the role of the tumor microenvironment in disease progression, stromal components of the tumor have become attractive targets for therapeutic intervention. Stromal accumulation of the glycosaminoglycan hyaluronan occurs in many tumor types and is frequently associat...

  10. Unbinding of Hyaluronan Accelerates the Enzymatic Activity of Bee Hyaluronidase

    OpenAIRE

    Iliás, Attila; Liliom, Károly; Greiderer-Kleinlercher, Brigitte; Reitinger, Stephan; Lepperdinger, Günter

    2011-01-01

    Hyaluronan (HA), a polymeric glycosaminoglycan ubiquitously present in higher animals, is hydrolyzed by hyaluronidases (HAases). Here, we used bee HAase as a model enzyme to study the HA-HAase interaction. Located in close proximity to the active center, a bulky surface loop, which appears to obstruct one end of the substrate binding groove, was found to be functionally involved in HA turnover. To better understand kinetic changes in substrate interaction, binding of high molecular weight HA ...

  11. Unbinding of Hyaluronan Accelerates the Enzymatic Acitivity of Bee Hyaluronidase

    OpenAIRE

    Iliás, A.; Greiderer-Kleinlercher, B.; Lepperdinger, G.; Liliom, K; Reitinger, S.

    2011-01-01

    Hyaluronan (HA), a polymeric glycosaminoglycan ubiquitously present in higher animals, is hydrolyzed by hyaluronidases (HAases). Here, we used bee HAase as a model enzyme to study the HA-HAase interaction. Located in close proximity to the active center, a bulky surface loop, which appears to obstruct one end of the substrate binding groove, was found to be functionally involved in HA turnover. To better understand kinetic changes in substrate interaction, binding of high molecular weight HA ...

  12. Hyaluronan Tumor Cell Interactions in Prostate Cancer Growth and Survival

    Science.gov (United States)

    2008-12-01

    RHAMM remaining following CD44 knockdown. Secondly, RHAMM will be knocked down using RNAi and the level of CD44 remaining will be measured using Western...hyaluronidase pretreatment or by using RNAi for the hyaluronan synthase enzymes expressed by these cells. The prediction, again, is that limiting HA...vertebrates and is not found in lower organisms or in insects (Fig. 9.2). Given its roles in such important cellular processes as motility and cell division in

  13. Hyaluronan-modified superparamagnetic iron oxide nanoparticles for bimodal breast cancer imaging and photothermal therapy

    Science.gov (United States)

    Yang, Rui-Meng; Fu, Chao-Ping; Fang, Jin-Zhi; Xu, Xiang-Dong; Wei, Xin-Hua; Tang, Wen-Jie; Jiang, Xin-Qing; Zhang, Li-Ming

    2017-01-01

    Theranostic nanoparticles with both imaging and therapeutic abilities are highly promising in successful diagnosis and treatment of the most devastating cancers. In this study, the dual-modal imaging and photothermal effect of hyaluronan (HA)-modified superparamagnetic iron oxide nanoparticles (HA-SPIONs), which was developed in a previous study, were investigated for CD44 HA receptor-overexpressing breast cancer in both in vitro and in vivo experiments. Heat is found to be rapidly generated by near-infrared laser range irradiation of HA-SPIONs. When incubated with CD44 HA receptor-overexpressing MDA-MB-231 cells in vitro, HA-SPIONs exhibited significant specific cellular uptake and specific accumulation confirmed by Prussian blue staining. The in vitro and in vivo results of magnetic resonance imaging and photothermal ablation demonstrated that HA-SPIONs exhibited significant negative contrast enhancement on T2-weighted magnetic resonance imaging and photothermal effect targeted CD44 HA receptor-overexpressing breast cancer. All these results indicated that HA-SPIONs have great potential for effective diagnosis and treatment of cancer. PMID:28096667

  14. Influence of water content and drying on the physical structure of native hyaluronan

    NARCIS (Netherlands)

    Prusova, A.; Vergeldt, F.J.; Kucerik, J.

    2013-01-01

    Hydration properties of semi-diluted hyaluronan were studied by means of time domain nuclear magnetic resonance. Based on the transverse proton relaxation times T2, the plasticization of hyaluronan which was precipitated by isopropylalcohol and dried in the oven have been determined at water content

  15. Oleyl-hyaluronan micelles loaded with upconverting nanoparticles for bio-imaging

    Energy Technology Data Exchange (ETDEWEB)

    Pospisilova, Martina, E-mail: martina.pospisilova@contipro.com; Mrazek, Jiri; Matuska, Vit; Kettou, Sofiane; Dusikova, Monika; Svozil, Vit; Nesporova, Kristina; Huerta-Angeles, Gloria; Vagnerova, Hana; Velebny, Vladimir [Contipro Biotech (Czech Republic)

    2015-09-15

    Hyaluronan (HA) represents an interesting polymer for nanoparticle coating due to its biocompatibility and enhanced cell interaction via CD44 receptor. Here, we describe incorporation of oleate-capped β–NaYF{sub 4}:Yb{sup 3+}, Er{sup 3+} nanoparticles (UCNP-OA) into amphiphilic HA by microemulsion method. Resulting structures have a spherical, micelle-like appearance with a hydrodynamic diameter of 180 nm. UCNP-OA-loaded HA micelles show a good stability in PBS buffer and cell culture media. The intensity of green emission of UCNP-OA-loaded HA micelles in water is about five times higher than that of ligand-free UCNP, indicating that amphiphilic HA effectively protects UCNP luminescence from quenching by water molecules. We found that UCNP-OA-loaded HA micelles in concentrations up to 50 μg mL{sup −1} increase cell viability of normal human dermal fibroblasts (NHDF), while viability of human breast adenocarcinoma cells MDA–MB–231 is reduced at these concentrations. The utility of UCNP-OA-loaded HA micelles as a bio-imaging probe was demonstrated in vitro by successful labelling of NHDF and MDA–MB–231 cells overexpressing the CD44 receptor.

  16. Identification of lymphatics in the ciliary body of the human eye: a novel "uveolymphatic" outflow pathway.

    Science.gov (United States)

    Yücel, Yeni H; Johnston, Miles G; Ly, Tina; Patel, Manoj; Drake, Brian; Gümüş, Ersin; Fraenkl, Stephan A; Moore, Sara; Tobbia, Dalia; Armstrong, Dianna; Horvath, Eva; Gupta, Neeru

    2009-11-01

    Impaired aqueous humor flow from the eye may lead to elevated intraocular pressure and glaucoma. Drainage of aqueous fluid from the eye occurs through established routes that include conventional outflow via the trabecular meshwork, and an unconventional or uveoscleral outflow pathway involving the ciliary body. Based on the assumption that the eye lacks a lymphatic circulation, the possible role of lymphatics in the less well defined uveoscleral pathway has been largely ignored. Advances in lymphatic research have identified specific lymphatic markers such as podoplanin, a transmembrane mucin-type glycoprotein, and lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1). Lymphatic channels were identified in the human ciliary body using immunofluorescence with D2-40 antibody for podoplanin, and LYVE-1 antibody. In keeping with the criteria for lymphatic vessels in conjunctiva used as positive control, D2-40 and LYVE-1-positive lymphatic channels in the ciliary body had a distinct lumen, were negative for blood vessel endothelial cell marker CD34, and were surrounded by either discontinuous or no collagen IV-positive basement membrane. Cryo-immunogold electron microscopy confirmed the presence D2-40-immunoreactivity in lymphatic endothelium in the human ciliary body. Fluorescent nanospheres injected into the anterior chamber of the sheep eye were detected in LYVE-1-positive channels of the ciliary body 15, 30, and 45 min following injection. Four hours following intracameral injection, Iodine-125 radio-labeled human serum albumin injected into the sheep eye (n = 5) was drained preferentially into cervical, retropharyngeal, submandibular and preauricular lymph nodes in the head and neck region compared to reference popliteal lymph nodes (P human ciliary body, and that fluid and solutes flow at least partially through this system. The discovery of a uveolymphatic pathway in the eye is novel and highly relevant to studies of glaucoma and other eye diseases.

  17. A Hyaluronan-Based Injectable Hydrogel Improves the Survival and Integration of Stem Cell Progeny following Transplantation

    Directory of Open Access Journals (Sweden)

    Brian G. Ballios

    2015-06-01

    Full Text Available The utility of stem cells and their progeny in adult transplantation models has been limited by poor survival and integration. We designed an injectable and bioresorbable hydrogel blend of hyaluronan and methylcellulose (HAMC and tested it with two cell types in two animal models, thereby gaining an understanding of its general applicability for enhanced cell distribution, survival, integration, and functional repair relative to conventional cell delivery in saline. HAMC improves cell survival and integration of retinal stem cell (RSC-derived rods in the retina. The pro-survival mechanism of HAMC is ascribed to the interaction of the CD44 receptor with HA. Transient disruption of the retinal outer limiting membrane, combined with HAMC delivery, results in significantly improved rod survival and visual function. HAMC also improves the distribution, viability, and functional repair of neural stem and progenitor cells (NSCs. The HAMC delivery system improves cell transplantation efficacy in two CNS models, suggesting broad applicability.

  18. Hyaluronan-modified superparamagnetic iron oxide nanoparticles for bimodal breast cancer imaging and photothermal therapy

    Directory of Open Access Journals (Sweden)

    Yang R

    2016-12-01

    Full Text Available Rui-Meng Yang,1,* Chao-Ping Fu,2,* Jin-Zhi Fang,1 Xiang-Dong Xu,1 Xin-Hua Wei,1 Wen-Jie Tang,1 Xin-Qing Jiang,1 Li-Ming Zhang2 1Department of Radiology, Guangzhou First People’s Hospital, Guangzhou Medical University, 2School of Materials Science and Engineering, School of Chemistry, Sun Yat-sen University, Guangzhou, China *These authors contributed equally to this work Abstract: Theranostic nanoparticles with both imaging and therapeutic abilities are highly promising in successful diagnosis and treatment of the most devastating cancers. In this study, the dual-modal imaging and photothermal effect of hyaluronan (HA-modified superparamagnetic iron oxide nanoparticles (HA-SPIONs, which was developed in a previous study, were investigated for CD44 HA receptor-overexpressing breast cancer in both in vitro and in vivo experiments. Heat is found to be rapidly generated by near-infrared laser range irradiation of HA-SPIONs. When incubated with CD44 HA receptor-overexpressing MDA-MB-231 cells in vitro, HA-SPIONs exhibited significant specific cellular uptake and specific accumulation confirmed by Prussian blue staining. The in vitro and in vivo results of magnetic resonance imaging and photothermal ablation demonstrated that HA-SPIONs exhibited significant negative contrast enhancement on T2-weighted magnetic resonance imaging and photothermal effect targeted CD44 HA receptor-overexpressing breast cancer. All these results indicated that HA-SPIONs have great potential for effective diagnosis and treatment of cancer. Keywords: iron oxide nanoparticles, surface functionalization, bioactive glycosaminoglycan, magnetic resonance imaging, cellular uptake, breast carcinoma

  19. Hyaluronan - a functional and structural sweet spot in the tissue microenvironment

    Directory of Open Access Journals (Sweden)

    James eMonslow

    2015-05-01

    Full Text Available Transition from homeostatic to reactive matrix remodeling is a fundamental adaptive tissue response to injury, inflammatory disease, fibrosis and cancer. Alterations in architecture, physical properties and matrix composition result in changes in biomechanical and biochemical cellular signaling. The dynamics of pericellular and extracellular matrices, including matrix protein, proteoglycan and glycosaminoglycan modification are continually emerging as essential regulatory mechanisms underlying cellular and tissue function. Nevertheless, the impact of matrix organization on inflammation and immunity in particular, and the consequent effects on tissue healing and disease outcome are arguably under-studied aspects of adaptive stress responses. Herein, we review how the predominant glycosaminoglycan hyaluronan (HA contributes to the structure and function of the tissue microenvironment. Specifically, we examine the evidence of HA degradation and the generation of biologically-active smaller HA fragments in pathological settings in vivo. We discuss how HA fragments versus nascent HA via alternate receptor-mediated signaling influence inflammatory cell recruitment and differentiation, resident cell activation, as well as tumor growth, survival and metastasis. Finally, we discuss how HA fragmentation impacts restoration of normal tissue function and pathological outcomes in disease.

  20. Evaluation of emulsion electrospun polycaprolactone/hyaluronan/epidermal growth factor nanofibrous scaffolds for wound healing.

    Science.gov (United States)

    Wang, Zhenbei; Qian, Yuna; Li, Linhao; Pan, Lianhong; Njunge, Lucy W; Dong, Lili; Yang, Li

    2016-01-01

    Wound healing scaffolds provide cells with structural integrity and can also deliver biological agents to establish a skin tissue-specific microenvironment to regulate cell functions and to accelerate the healing process. In this study, we fabricated biodegradable nanofibrous scaffolds with an emulsion electrospinning technique. The scaffolds were composed of polycaprolactone, hyaluronan and encapsulating epidermal growth factor. The morphology and core-sheath structure of the nanofibers were characterized by scanning electron microscopy and transmission electron microscopy. The scaffolds were also characterized for chemical composition and hydrophilicity with a Fourier-transform infrared analysis, energy dispersive spectroscopy and the water contact angle. An in vitro model protein bovine serum albumin and epidermal growth factor release study was conducted to evaluate the sustained release potential of the core-sheath structured nanofibers with and without the hyaluronan component. Additionally, an in vitro cultivation of human skin keratinocytes (HaCaT) and fibroblasts on polycaprolactone/hyaluronan and polycaprolactone/hyaluronan-epidermal growth factor scaffolds showed a significant synergistic effect of hyaluronan and epidermal growth factor on cell proliferation and infiltration. Furthermore, there was an up-regulation of the wound-healing-related genes collagen I, collagen III and TGF-β in polycaprolactone/hyaluronan/epidermal growth factor scaffolds compared with control groups. In the full-thickness wound model, the enhanced regeneration of fully functional skin was facilitated by epidermal regeneration in the polycaprolactone/hyaluronan/epidermal growth factor treatment group. Our findings suggest that bioactivity and hemostasis of the hyaluronan-based nanofibrous scaffolds have the capability to encapsulate and control the release of growth factors that can serve as skin tissue engineering scaffolds for wound healing.

  1. HABP2 is a novel regulator of hyaluronan-mediated human lung cancer progression

    OpenAIRE

    Tamara eMirzapoiazova; Nurbek eMambetsariev; Frances E Lennon; Bolot eMambetsariev; Joshua E. Berlind; Ravi eSalgia; Singleton, Patrick A.

    2015-01-01

    Background: Lung cancer is a devastating disease with limited treatment options. Many lung cancers have changes in their microenvironment including upregulation of the extracellular matrix glycosaminoglycan, hyaluronan (HA), which we have previously demonstrated can regulate the activity of the extracellular serine protease, Hyaluronan Binding Protein 2 (HABP2). This study examined the functional role of HABP2 on HA-mediated human lung cancer dynamics.Methods: Immunohistochemical analysis was...

  2. HABP2 is a Novel Regulator of Hyaluronan-Mediated Human Lung Cancer Progression

    OpenAIRE

    Mirzapoiazova, Tamara; Mambetsariev, Nurbek; Frances E Lennon; Mambetsariev, Bolot; Joshua E. Berlind; Salgia, Ravi; Singleton, Patrick A.

    2015-01-01

    Background Lung cancer is a devastating disease with limited treatment options. Many lung cancers have changes in their microenvironment including upregulation of the extracellular matrix glycosaminoglycan, hyaluronan (HA), which we have previously demonstrated can regulate the activity of the extracellular serine protease, hyaluronan binding protein 2 (HABP2). This study examined the functional role of HABP2 on HA-mediated human lung cancer dynamics. Methods Immunohistochemical an...

  3. [Hyaluronic acid (hyaluronan) levels in pathological human saphenous veins. Effects of procyanidol oligomers].

    Science.gov (United States)

    Drubaix, I; Maraval, M; Robert, L; Robert, A M

    1997-01-01

    We investigated the hyaluronan content in the pathologic human venous wall using an ELSA assay with hyaluronectin according to the method of Delpech et al. The mean hyaluronan content in the 74 fragments from 12 venous walls studied was 596 +/- 528 ng/mg dry weight. These 12 venous walls could be separated in 3 distinct groups according to their hyaluronan content, low (277 +/- 141 ng/mg dry weight), moderate (552 +/- 361 ng/m dry weight) or high (1299 +/- 568 ng/mg dry weight). The differences between these groups are significant (p < 0.001). The presence of a veino-lymphatic oedema was generally associated with a high hyaluronan level (in 65% of cases). The 3H-glucosamine incorporation in cultured venous wall explants showed a 35% increase (p < 0.002) in varicosis as compared with the non or less modified segments of the vein and a 29% (p < 0.001) increase in presence of a veino-lymphatic oedema. The addition of 1 mg/ml of PCO (Procyanidolic Oligomers) to the culture media induced near to 20% decrease of the 3H-glucosamine incorporation and a 34% decrease of the hyaluronan content. Our results confirm the role of local overproduction of hyaluronan in the establishment of oedema and the potential effect of PCO to counteract it.

  4. A Hyaluronan-Based Scaffold for the in Vitro Construction of Dental Pulp-Like Tissue

    Directory of Open Access Journals (Sweden)

    Letizia Ferroni

    2015-03-01

    Full Text Available Dental pulp tissue supports the vitality of the tooth, but it is particularly vulnerable to external insults, such as mechanical trauma, chemical irritation or microbial invasion, which can lead to tissue necrosis. In the present work, we present an endodontic regeneration method based on the use of a tridimensional (3D hyaluronan scaffold and human dental pulp stem cells (DPSCs to produce a functional dental pulp-like tissue in vitro. An enriched population of DPSCs was seeded onto hyaluronan-based non-woven meshes in the presence of differentiation factors to induce the commitment of stem cells to neuronal, glial, endothelial and osteogenic phenotypes. In vitro experiments, among which were gene expression profiling and immunofluorescence (IF staining, proved the commitment of DPSCs to the main components of dental pulp tissue. In particular, the hyaluronan-DPSCs construct showed a dental pulp-like morphology consisting of several specialized cells growing inside the hyaluronan fibers. Furthermore, these constructs were implanted into rat calvarial critical-size defects. Histological analyses and gene expression profiling performed on hyaluronan-DPSCs grafts showed the regeneration of osteodentin-like tissue. Altogether, these data suggest the regenerative potential of the hyaluronan-DPSC engineered tissue.

  5. Priming Adipose-Derived Mesenchymal Stem Cells with Hyaluronan Alters Growth Kinetics and Increases Attachment to Articular Cartilage

    Directory of Open Access Journals (Sweden)

    Peter Succar

    2016-01-01

    Full Text Available Background. Biological therapeutics such as adipose-derived mesenchymal stem cell (MSC therapy are gaining acceptance for knee-osteoarthritis (OA treatment. Reports of OA-patients show reductions in cartilage defects and regeneration of hyaline-like-cartilage with MSC-therapy. Suspending MSCs in hyaluronan commonly occurs in animals and humans, usually without supporting data. Objective. To elucidate the effects of different concentrations of hyaluronan on MSC growth kinetics. Methods. Using a range of hyaluronan concentrations, we measured MSC adherence and proliferation on culture plastic surfaces and a novel cartilage-adhesion assay. We employed time-course and dispersion imaging to assess MSC binding to cartilage. Cytokine profiling was also conducted on the MSC-secretome. Results. Hyaluronan had dose-dependent effects on growth kinetics of MSCs at concentrations of entanglement point (1 mg/mL. At higher concentrations, viscosity effects outweighed benefits of additional hyaluronan. The cartilage-adhesion assay highlighted for the first time that hyaluronan-primed MSCs increased cell attachment to cartilage whilst the presence of hyaluronan did not. Our time-course suggested patients undergoing MSC-therapy for OA could benefit from joint-immobilisation for up to 8 hours. Hyaluronan also greatly affected dispersion of MSCs on cartilage. Conclusion. Our results should be considered in future trials with MSC-therapy using hyaluronan as a vehicle, for the treatment of OA.

  6. Regulation of Synthesis and Roles of Hyaluronan in Peritoneal Dialysis

    Directory of Open Access Journals (Sweden)

    Timothy Bowen

    2015-01-01

    Full Text Available Hyaluronan (HA is a ubiquitous extracellular matrix glycosaminoglycan composed of repeated disaccharide units of alternating D-glucuronic acid and D-N-acetylglucosamine residues linked via alternating β-1,4 and β-1,3 glycosidic bonds. HA is synthesized in humans by HA synthase (HAS enzymes 1, 2, and 3, which are encoded by the corresponding HAS genes. Previous in vitro studies have shown characteristic changes in HAS expression and increased HA synthesis in response to wounding and proinflammatory cytokines in human peritoneal mesothelial cells. In addition, in vivo models and human peritoneal biopsy samples have provided evidence of changes in HA metabolism in the fibrosis that at present accompanies peritoneal dialysis treatment. This review discusses these published observations and how they might contribute to improvement in peritoneal dialysis.

  7. Rheological properties of aqueous solutions of biopolymeric hyaluronan

    Science.gov (United States)

    Szwajczak, Elzbieta

    2004-09-01

    Aqueous solutions of hyaluronic acid (hyaluronan, HA) were studied. The HA compound is a natural polysaccharide, bipolymer. It plays an important role in numerous biological processes as a component of the extracellular matrix, connective tissues and, especially, human and animal synovial joints. Natural and artificial solutions of the HA have demonstrated the viscoelastic nature. These properties are shown to be related to the microstructure parameters (bulk concentration, molecular weight) and external parameters (temperature, stress, shear rate). We emphasize the role of the flow properties of polymeric systems. It is found a liquid crystalline "order" can be "induced" during the material flow. The dynamic properties, such as the elastic shear modulus and viscous shear modulus, are given. These results are discussed in relation to the postulated function of hyaluronic acid in synovial joint and with respect to possibilities o their application in medicine and pharmacology.

  8. A novel photopolymerizable derivative of hyaluronan for designed hydrogel formation.

    Science.gov (United States)

    Bobula, Tomáš; Buffa, Radovan; Hermannová, Martina; Kohutová, Lenka; Procházková, Pavlína; Vágnerová, Hana; Čepa, Martin; Wolfová, Lucie; Židek, Ondřej; Velebný, Vladimír

    2017-04-01

    A new photopolymerizable derivative of hyaluronan (methacrylhydrazide-HA, MAHA) was prepared by carbodiimide chemistry. The reaction conditions were optimized for molecular weight (Mw), reaction time and amount of reagents with a degree of methacrylation (DM) ranging from 2% to 58%. Methacrylhydrazide-HA was hydrolytically stable (PBS, 7days, 37°C) in contrast to commonly used methacrylester analoque (23% hydrolyzed). MAHA readily photopolymerized into densely crosslinked hydrogels under physiological conditions. The varied DM, Mw, irradiation time (texp) and macromer concentration in photocrosslinking afforded hydrogels with different physical (swelling ratio, degradation rate) and mechanical properties (stiffness, toughness). Three-dimensional fabrication and surface patterning of MAHA hydrogels were demonstrated by photolithography and light mediated micromolding. A live-dead assay with skin fibroblasts showed convenient biocompatibility of MAHA (16%, 116kDa) for potential scaffolding applications in tissue engineering and regenerative medicine.

  9. Hyaluronan synthases (HAS1-3 and hyaluronidases (HYAL1-2 in the accumulation of hyaluronan in endometrioid endometrial carcinoma

    Directory of Open Access Journals (Sweden)

    Kosma Veli-Matti

    2010-09-01

    Full Text Available Abstract Background Hyaluronan accumulation correlates with the degree of malignancy in many solid tumor types, including malignant endometrial carcinomas. To elucidate the mechanism of hyaluronan accumulation, we examined the expression levels of the hyaluronan synthases (HAS1, HAS2 and HAS3 and hyaluronidases (HYAL1 and HYAL2, and correlated them with hyaluronan content and HAS1-3 immunoreactivity. Methods A total of 35 endometrial tissue biopsies from 35 patients, including proliferative and secretory endometrium (n = 10, post-menopausal proliferative endometrium (n = 5, complex atypical hyperplasia (n = 4, grade 1 (n = 8 and grade 2 + 3 (n = 8 endometrioid adenocarcinomas were divided for gene expression by real-time RT-PCR, and paraffin embedded blocks for hyaluronan and HAS1-3 cytochemistry. Results The mRNA levels of HAS1-3 were not consistently changed, while the immunoreactivity of all HAS proteins was increased in the cancer epithelium. Interestingly, HAS3 mRNA, but not HAS3 immunoreactivity, was increased in post-menopausal endometrium compared to normal endometrium (p = 0.003. The median of HYAL1 mRNA was 10-fold and 15-fold lower in both grade 1 and grade 2+3 endometrioid endometrial cancers, as compared to normal endometrium (p = 0.004-0.006, and post-menopausal endometrium (p = 0.002, respectively. HYAL2 mRNA was also reduced in cancer (p = 0.02 and correlated with HYAL1 (r = 0.8, p = 0.0001. There was an inverse correlation between HYAL1 mRNA and the epithelial hyaluronan staining intensity (r = -0.6; P = 0.001. Conclusion The results indicated that HYAL1 and HYAL2 were coexpressed and significantly downregulated in endometrioid endometrial cancer and correlated with the accumulation of hyaluronan. While immunoreactivity for HASs increased in the cancer cells, tumor mRNA levels for HASs were not changed, suggesting that reduced turnover of HAS protein may also have contributed to the accumulation of hyaluronan.

  10. Hyaluronan synthase mediates dye translocation across liposomal membranes

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    Medina Andria P

    2012-01-01

    Full Text Available Abstract Background Hyaluronan (HA is made at the plasma membrane and secreted into the extracellular medium or matrix by phospolipid-dependent hyaluronan synthase (HAS, which is active as a monomer. Since the mechanism by which HA is translocated across membranes is still unresolved, we assessed the presence of an intraprotein pore within HAS by adding purified Streptococcus equisimilis HAS (SeHAS to liposomes preloaded with the fluorophore Cascade Blue (CB. Results CB translocation (efflux was not observed with mock-purified material from empty vector control E. coli membranes, but was induced by SeHAS, purified from membranes, in a time- and dose-dependent manner. CB efflux was eliminated or greatly reduced when purified SeHAS was first treated under conditions that inhibit enzyme activity: heating, oxidization or cysteine modification with N-ethylmaleimide. Reduced CB efflux also occurred with SeHAS K48E or K48F mutants, in which alteration of K48 within membrane domain 2 causes decreased activity and HA product size. The above results used liposomes containing bovine cardiolipin (BCL. An earlier study testing many synthetic lipids found that the best activating lipid for SeHAS is tetraoleoyl cardiolipin (TO-CL and that, in contrast, tetramyristoyl cardiolipin (TM-CL is an inactivating lipid (Weigel et al, J. Biol. Chem. 281, 36542, 2006. Consistent with the effects of these CL species on SeHAS activity, CB efflux was more than 2-fold greater in liposomes made with TO-CL compared to TM-CL. Conclusions The results indicate the presence of an intraprotein pore in HAS and support a model in which HA is translocated to the exterior by HAS itself.

  11. Modulation of Hyaluronan Synthesis by the Interaction between Mesenchymal Stem Cells and Osteoarthritic Chondrocytes

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    Eliane Antonioli

    2015-01-01

    Full Text Available Bone marrow mesenchymal stem cells (BM-MSCs are considered a good source for cellular therapy in cartilage repair. But, their potential to repair the extracellular matrix, in an osteoarthritic environment, is still controversial. In osteoarthritis (OA, anti-inflammatory action and extracellular matrix production are important steps for cartilage healing. This study examined the interaction of BM-MSC and OA-chondrocyte on the production of hyaluronan and inflammatory cytokines in a Transwell system. We compared cocultured BM-MSCs and OA-chondrocytes with the individually cultured controls (monocultures. There was a decrease in BM-MSCs cell count in coculture with OA-chondrocytes when compared to BM-MSCs alone. In monoculture, BM-MSCs produced higher amounts of hyaluronan than OA-chondrocytes and coculture of BM-MSCs with OA-chondrocytes increased hyaluronan production per cell. Hyaluronan synthase-1 mRNA expression was upregulated in BM-MSCs after coculture with OA-chondrocytes, whereas hyaluronidase-1 was downregulated. After coculture, lower IL-6 levels were detected in BM-MSCs compared with OA-chondrocytes. These results indicate that, in response to coculture with OA-chondrocytes, BM-MSCs change their behavior by increasing production of hyaluronan and decreasing inflammatory cytokines. Our results indicate that BM-MSCs per se could be a potential tool for OA regenerative therapy, exerting short-term effects on the local microenvironment even when cell:cell contact is not occurring.

  12. On the demixing of hyaluronan and alginate in the gel state.

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    Scognamiglio, Francesca; Travan, Andrea; Cok, Michela; Borgogna, Massimiliano; Marsich, Eleonora; Paoletti, Sergio; Donati, Ivan

    2017-02-01

    The manuscript focuses on the demixing of hyaluronan and alginate in the hydrogel state. Binary solutions of the two polysaccharides have been treated with Ca(2+) as the alginate cross-linking ion and the radial distribution of the two components in the hydrogels was measured by means of (1)H NMR. These results revealed the presence of alginate-enriched and hyaluronan-enriched domains stemming from a polysaccharide demixing. The hydrogels were characterized by means of uniaxial compression and creep-compliance measurements which showed that the demixing increased the overall resistance of the hydrogel to stress. In addition, due to the viscoelastic properties of hyaluronan, a marked increase of the Newtonian viscosity of the constructs was noticed. The peculiarity of the effect of hyaluronan was demonstrated by the use of an alginate unable to form gel by binding non-calcium binding alginate, i.e. mannuronan, ruling out the effect of viscosity over the time-dependent behavior of the mixed hyaluronan-alginate hydrogels. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Oxidized low density lipoprotein (LDL) affects hyaluronan synthesis in human aortic smooth muscle cells.

    Science.gov (United States)

    Viola, Manuela; Bartolini, Barbara; Vigetti, Davide; Karousou, Evgenia; Moretto, Paola; Deleonibus, Sara; Sawamura, Tatsuya; Wight, Thomas N; Hascall, Vincent C; De Luca, Giancarlo; Passi, Alberto

    2013-10-11

    Thickening of the vessel in response to high low density lipoprotein(s) (LDL) levels is a hallmark of atherosclerosis, characterized by increased hyaluronan (HA) deposition in the neointima. Human native LDL trapped within the arterial wall undergoes modifications such as oxidation (oxLDL). The aim of our study is to elucidate the link between internalization of oxLDL and HA production in vitro, using human aortic smooth muscle cells. LDL were used at an effective protein concentration of 20-50 μg/ml, which allowed 80% cell viability. HA content in the medium of untreated cells was 28.9 ± 3.7 nmol HA-disaccharide/cell and increased after oxLDL treatment to 53.9 ± 5.6. OxLDL treatments doubled the transcripts of HA synthase HAS2 and HAS3. Accumulated HA stimulated migration of aortic smooth muscle cells and monocyte adhesiveness to extracellular matrix. The effects induced by oxLDL were inhibited by blocking LOX-1 scavenger receptor with a specific antibody (10 μg/ml). The cholesterol moiety of LDL has an important role in HA accumulation because cholesterol-free oxLDL failed to induce HA synthesis. Nevertheless, cholesterol-free oxLDL and unmodified cholesterol (20 μg/ml) induce only HAS3 transcription, whereas 22,oxysterol affects both HAS2 and HAS3. Moreover, HA deposition was associated with higher expression of endoplasmic reticulum stress markers (CHOP and GRP78). Our data suggest that HA synthesis can be induced in response to specific oxidized sterol-related species delivered through oxLDL.

  14. Biological interplay between proteoglycans and their innate immune receptors in inflammation.

    Science.gov (United States)

    Frey, Helena; Schroeder, Nina; Manon-Jensen, Tina; Iozzo, Renato V; Schaefer, Liliana

    2013-05-01

    An emerging body of evidence indicates that secreted proteoglycans act as signaling molecules, in addition to their canonical function in maintaining and regulating the architecture of various extracellular matrices. Proteoglycans interact with a number of receptors that regulate growth, motility and immune response. In part, as a consequence of their complex structure, proteoglycans can induce crosstalk among various families of receptors and can also interact with natural receptor ligands, often blocking and sequestering their bioactivity. In their soluble form, originating from either partial proteolytic processing or through de novo synthesis by activated cells, some proteoglycans can become potent danger signals, denoting tissue stress and injury. Recently, it has been shown that proteoglycans, especially those belonging to the small leucine-rich and hyaluronan-binding gene families as well as the glycosaminoglycan hyaluronan, act as endogenous ligands of the toll-like receptors, a group of central receptors regulating innate immunity. Furthermore, proteoglycans can activate intracellular inflammasomes and trigger sterile inflammation. In this review, we critically assess the signaling events induced by the proteoglycans biglycan, decorin, lumican and versican as well as hyaluronan during inflammation. We discuss the intriguing emerging notion that, in spite of structural diversity of biglycan, decorin, versican and hyaluronan, all of them signal through the same toll-like receptors, albeit triggering differential responses and biological outcomes. Finally, we review the modes of action of these endogenous ligands of toll-like receptors and their ability to specifically modify the final signaling events and the inflammatory response.

  15. Chromosomal localization of the human and mouse hyaluronan synthase genes

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    Spicer, A.P.; McDonald, J.A. [Mayo Clinic Scottsdale, AZ (United States); Seldin, M.F. [Univ. of California Davis, CA (United States)] [and others

    1997-05-01

    We have recently identified a new vertebrate gene family encoding putative hyaluronan (HA) synthases. Three highly conserved related genes have been identified, designated HAS1, HAS2, and HAS3 in humans and Has1, Has2, and Has3 in the mouse. All three genes encode predicted plasma membrane proteins with multiple transmembrane domains and approximately 25% amino acid sequence identity to the Streptococcus pyogenes HA synthase, HasA. Furthermore, expression of any one HAS gene in transfected mammalian cells leads to high levels of HA biosynthesis. We now report the chromosomal localization of the three HAS genes in human and in mouse. The genes localized to three different positions within both the human and the mouse genomes. HAS1 was localized to the human chromosome 19q13.3-q13.4 boundary and Has1 to mouse Chr 17. HAS2 was localized to human chromosome 8q24.12 and Has2 to mouse Chr 15. HAS3 was localized to human chromosome 16q22.1 and Has3 to mouse Chr 8. The map position for HAS1 reinforces the recently reported relationship between a small region of human chromosome 19q and proximal mouse chromosome 17. HAS2 mapped outside the predicted critical region delineated for the Langer-Giedion syndrome and can thus be excluded as a candidate gene for this genetic syndrome. 33 refs., 2 figs.

  16. NMR study of hydroxy and amide protons in hyaluronan polymers.

    Science.gov (United States)

    Nestor, Gustav; Sandström, Corine

    2017-02-10

    Hyaluronan (HA) is an important and well characterized glycosaminoglycan with high viscosity and water-retaining capacity. Nonetheless, it is not fully understood whether conformational properties of the easily characterized HA oligomers can be transferred to HA polymers. To investigate possible differences in hydration, hydrogen bonding and flexibility between HA polymers and oligomers, hydroxy and amide protons of HA polymers were studied by solution-state and high-resolution magic angle spinning (HR-MAS) NMR spectroscopy. Measurements of chemical shifts, temperature coefficients and NOEs in HA polymers revealed that the NMR data are very similar compared to the interior of a HA octasaccharide, supporting transient hydrogen bond interactions across the β(1→3) and β(1→4) glycosidic linkages. However, differences in NOEs suggested a cis-like orientation between NH and H2 in the HA polymer. The lack of concentration dependence of the hydroxy proton chemical shifts suggests that there are no direct inter-chain interactions involving hydroxy protons at the concentrations investigated.

  17. Hyaluronan scaffold supports osteogenic differentiation of bone marrow concentrate cells.

    Science.gov (United States)

    Cavallo, C; Desando, G; Ferrari, A; Zini, N; Mariani, E; Grigolo, B

    2016-01-01

    Osteochondral lesions are considered a challenge for orthopedic surgeons. Currently, the treatments available are often unsatisfactory and unable to stimulate tissue regeneration. Tissue engineering offers a new therapeutic strategy, taking into account the role exerted by cells, biomaterial and growth factors in restoring tissue damage. In this light, Mesenchymal Stem Cells (MSCs) have been indicated as a fascinating tool for regenerative medicine thanks to their ability to differentiate into bone, cartilage and adipose tissue. However, in vitro-cultivation of MSCs could be associated with some risks such as de-differentiation/reprogramming, infection and contaminations of the cells. To overcome these shortcomings, a new approach is represented by the use of Bone Marrow Concentrate (BMC), that could allow the delivery of cells surrounded by their microenvironment in injured tissue. For this purpose, cells require a tridimensional scaffold that can support their adhesion, proliferation and differentiation. This study is focused on the potentiality of BMC seeded onto a hyaluronan-based scaffold (Hyaff-11) to differentiate into osteogenic lineage. This process depends on the specific interaction between cells derived from bone marrow (surrounded by their niche) and scaffold, that create an environment able to support the regeneration of damaged tissue. The data obtained from the present study demonstrate that BMC grown onto Hyaff-11 are able to differentiate toward osteogenic sense, producing specific osteogenic genes and matrix proteins.

  18. Study on Preparation and Release of Dexamethasone Hyaluronan Microspheres

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Hyaluronan (HA), the consistent glycosaminoglycans in extracellular matrix, is a kind of biomaterials with wonderful biocompatibility. To develop drug release system (DDS) with HA as drug carrier is a new hotspot in the field of pharmaceutics. In this paper, we applied technique of ultrosound and reversed phase (Water/Oil) emulsification to develop dexamethasone (DEX)-HA-STMP cross-linking microspheres (DEX-HA MS) with STMP as cross-linker. DEX-HA MS has a wonderful shape and property of dispersion. There is a negative correlation between diameter of DEX-HA MS and the content of cross-linker, or the content of emulsifier, and a positive correlation between the diameter and CHA. When CHA≤1% ,DEX/HA≤1/10(g/g),there is a positive correlation between the factors mentioned below and drug loading (DL%)/loading efficiency (LE%) ,the content of STMP, the content of emulsifier, CHA and the content of DEX. DEX-HA-MS can realize function of slow release. In vitro drug release experiment shows that cumulative release (CR%) of DEX-HA MS fits in with pervasion-corrosion equation, and there is a negative correlation between the content of STMP, CHA and CR% , a positive correlation between emulsifier and CR%. When DEX/HA ≤1/5 (g/g) there is a negative correlation between the content of DEX and CR%.

  19. Hyaluronan molecular weight is controlled by UDP-N-acetylglucosamine concentration in Streptococcus zooepidemicus.

    Science.gov (United States)

    Chen, Wendy Yiting; Marcellin, Esteban; Hung, Jacky; Nielsen, Lars Keld

    2009-07-03

    The molecular weight of hyaluronan is important for its rheological and biological function. The molecular mechanisms underlying chain termination and hence molecular weight control remain poorly understood, not only for hyaluronan synthases but also for other beta-polysaccharide synthases, e.g. cellulose, chitin, and 1,3-betaglucan synthases. In this work, we manipulated metabolite concentrations in the hyaluronan pathway by overexpressing the five genes of the hyaluronan synthesis operon in Streptococcus equi subsp. zooepidemicus. Overexpression of genes involved in UDP-glucuronic acid biosynthesis decreased molecular weight, whereas overexpression of genes involved in UDP-N-acetylglucosamine biosynthesis increased molecular weight. The highest molecular mass observed was at 3.4 +/- 0.1 MDa twice that observed in the wild-type strain, 1.8 +/- 0.1 MDa. The data indicate that (a) high molecular weight is achieved when an appropriate balance of UDP-N-acetylglucosamine and UDP-glucuronic acid is achieved, (b) UDP-N-acetylglucosamine exerts the dominant effect on molecular weight, and (c) the wild-type strain has suboptimal levels of UDP-N-acetylglucosamine. Consistent herewith molecular weight correlated strongly (rho = 0.84, p = 3 x 10(-5)) with the concentration of UDP-N-acetylglucosamine. Data presented in this paper represent the first model for hyaluronan molecular weight control based on the concentration of activated sugar precursors. These results can be used to engineer strains producing high molecular weight hyaluronan and may provide insight into similar polymerization mechanisms in other polysaccharides.

  20. Hyaluronan-CD44 interaction promotes growth of decidual stromal cells in human first-trimester pregnancy.

    Directory of Open Access Journals (Sweden)

    Rui Zhu

    Full Text Available Hyaluronan (HA and its receptor CD44 are expressed at the maternal-fetal interface, but its role in early pregnancy remains unclear. Here, we found that primary decidual stromal cells (DSCs continuously secreted HA and expressed its receptor CD44. Pregnancy-associated hormones up-regulated HA synthetase (HAS 2 transcription and HA release from DSCs. High molecular weight-HA (HMW-HA, but not medium molecular weight (MMW-HA or low molecular weight (LMW-HA, promoted proliferation and inhibited apoptosis of DSCs in a CD44-dependent manner. The in-cell Western analysis revealed HMW-HA activated PI3K/AKT and mitogen-activated protein kinase (MAPK/ERK1/2 signaling pathways time-dependently. Blocking these pathways by specific inhibitor LY294002 or U0126 abrogated HMW-HA-regulated DSc proliferation and apoptosis. Finally, we have found that HA content, HA molecular weight, HAS2 mRNA level, and CD44 expression were significantly decreased in DSCs from unexplained miscarriage compared with the normal pregnancy. Collectively, our results indicate that higher level and greater molecular mass of HA at maternal-fetal interface contributes to DSc growth and maintenance of DSCs in human early pregnancy.

  1. Serum hyaluronan and laminin level in children with chronic hepatitis B during long-term lamivudine treatment.

    Science.gov (United States)

    Lebensztejn, Dariusz Marek; Skiba, Elzbieta; Sobaniec-Lotowska, Maria Elzbieta; Kaczmarski, Maciej

    2007-01-01

    The aim was to assess the effect of long-term lamivudine treatment on liver fibrosis by direct assessment of histological scores and by indirect assessment of serum biomarkers in children with chronic hepatitis B (chB). The observation was carried out on 31 children with biopsy proven chB who were nonresponders to previous IFNalpha therapy. The serum concentration of hyaluronan and laminin were measured before and up to 24 months of therapy. ROC analysis was used to calculate the power of the assays to detect advanced liver fibrosis (score > 2 according to Batts & Ludwig). Serum hyaluronan and laminin level were significantly higher in children with chB compared to controls. There was a significant correlation between serum hyaluronan level and the stage of liver fibrosis. The ability of serum hyaluronan to differentiate children with advanced fibrosis from those with mild fibrosis was significant (AUC = 0.7767). Laminin did not allow a useful prediction. Two-year lamivudine treatment did not improve histological fibrosis but it caused significant decrease of serum hyaluronan level. Hyaluronan is a better fibrosis marker than laminin to diagnose children with advanced liver fibrosis. The significant decrease of hyaluronan level during therapy suggests antifibrotic effect of lamivudine in children with chB.

  2. Hyaluronan within fascia in the etiology of myofascial pain.

    Science.gov (United States)

    Stecco, Carla; Stern, R; Porzionato, A; Macchi, V; Masiero, S; Stecco, A; De Caro, R

    2011-12-01

    The layers of loose connective tissue within deep fasciae were studied with particular emphasis on the histochemical distribution of hyaluronan (HA). Samples of deep fascia together with the underlying muscles were taken from neck, abdomen and thigh from three fresh non-embalmed cadavers. Samples were stained with hematoxylin-eosin, Azan-Mallory, Alcian blue and a biotinylated HA-binding protein specific for HA. An ultrasound study was also performed on 22 voluntary subjects to analyze the thickness of these deep fasciae and their sublayers. The deep fascia presented a layer of HA between fascia and the muscle and within the loose connective tissue that divided different fibrous sublayers of the deep fascia. A layer of fibroblast-like cells that stained prominently with Alcian blue stain was observed. It was postulated that these are cells specialized for the biosynthesis of the HA-rich matrix. These cells we have termed "fasciacytes", and may represent a new class of cells not previously recognized. The ultrasound study highlighted a mean thickness of 1.88 mm of the fascia lata, 1.68 mm of the rectus sheath, and 1.73 mm of the sternocleidomastoid fascia. The HA within the deep fascia facilitates the free sliding of two adjacent fibrous fascial layers, thus promoting the normal function associated with the deep fascia. If the HA assumes a more packed conformation, or more generally, if the loose connective tissue inside the fascia alters its density, the behavior of the entire deep fascia and the underlying muscle would be compromised. This, we predict, may be the basis of the common phenomenon known as "myofascial pain."

  3. Crucial role of hyaluronan in neointimal formation after vascular injury.

    Directory of Open Access Journals (Sweden)

    Yuichiro Kashima

    Full Text Available BACKGROUND: Hyaluronan (HA is a primary component of the extracellular matrix of cells, and it is involved in the pathogenesis of atherosclerosis. The purpose of this study was to investigate the role of HA in neointimal formation after vascular injury and determine its tissue-specific role in vascular smooth muscle cells (VSMCs by using a cre-lox conditional transgenic (cTg strategy. METHODS AND RESULTS: HA was found to be expressed in neointimal lesions in humans with atherosclerosis and after wire-mediated vascular injury in mice. Inhibition of HA synthesis using 4-methylumbelliferone markedly inhibited neointimal formation after injury. In vitro experiments revealed that low-molecular-weight HA (LMW-HA induced VSMC activation, including migration, proliferation, and production of inflammatory cytokines, and reactive oxygen species (ROS. The migration and proliferation of VSMCs were mediated by the CD44/RhoA and CD44/ERK1/2 pathways, respectively. Because HA synthase 2 (HAS2 is predominantly expressed in injured arteries, we generated cTg mice that overexpress the murine HAS2 gene specifically in VSMCs (cHAS2/CreSM22α mice and showed that HA overexpression markedly enhanced neointimal formation after cuff-mediated vascular injury. Further, HA-overexpressing VSMCs isolated from cHAS2/CreSM22α mice showed augmented migration, proliferation, and production of inflammatory cytokines and ROS. CONCLUSION: VSMC-derived HA promotes neointimal formation after vascular injury, and HA may be a potential therapeutic target for cardiovascular disease.

  4. Alginate-hyaluronan composite hydrogels accelerate wound healing process.

    Science.gov (United States)

    Catanzano, O; D'Esposito, V; Acierno, S; Ambrosio, M R; De Caro, C; Avagliano, C; Russo, P; Russo, R; Miro, A; Ungaro, F; Calignano, A; Formisano, P; Quaglia, F

    2015-10-20

    In this paper we propose polysaccharide hydrogels combining alginate (ALG) and hyaluronan (HA) as biofunctional platform for dermal wound repair. Hydrogels produced by internal gelation were homogeneous and easy to handle. Rheological evaluation of gelation kinetics of ALG/HA mixtures at different ratios allowed understanding the HA effect on ALG cross-linking process. Disk-shaped hydrogels, at different ALG/HA ratio, were characterized for morphology, homogeneity and mechanical properties. Results suggest that, although the presence of HA does significantly slow down gelation kinetics, the concentration of cross-links reached at the end of gelation is scarcely affected. The in vitro activity of ALG/HA dressings was tested on adipose derived multipotent adult stem cells (Ad-MSC) and an immortalized keratinocyte cell line (HaCaT). Hydrogels did not interfere with cell viability in both cells lines, but significantly promoted gap closure in a scratch assay at early (1 day) and late (5 days) stages as compared to hydrogels made of ALG alone (p<0.01 and 0.001 for Ad-MSC and HaCaT, respectively). In vivo wound healing studies, conducted on a rat model of excised wound indicated that after 5 days ALG/HA hydrogels significantly promoted wound closure as compared to ALG ones (p<0.001). Overall results demonstrate that the integration of HA in a physically cross-linked ALG hydrogel can be a versatile strategy to promote wound healing that can be easily translated in a clinical setting.

  5. Stimulation of porcine bone marrow stromal cells by hyaluronan, dexamethasone and rhBMP-2

    DEFF Research Database (Denmark)

    Zou, Xuenong; Li, Haisheng; Chen, Li

    2004-01-01

    In the interest of optimizing osteogenesis in in vitro, the present study sought to determine how porcine bone marrow stromal cell (BMSc) would respond to different concentrations of hyaluronan (HY) and its different combinations with dexamethasone (Dex) and recombinant human bone morphogenic pro...

  6. Splanchnic and renal extraction of circulating hyaluronan in patients with alcoholic liver disease

    DEFF Research Database (Denmark)

    Henriksen, Jens Henrik; Bentsen, K D; Laurent, T C

    1988-01-01

    hyaluronan was inversely correlated to indocyanine green clearance (r = -0.85, P less than 0.001) and to galactose elimination capacity (r = -0.62, P less than 0.02), but positively correlated to portal pressure (determined as wedged-to-free hepatic vein pressure) (r = 0.92, P less than 0.001). Splanchnic...

  7. Synthesis of a hexasaccharide partial sequence of hyaluronan for click chemistry and more

    Directory of Open Access Journals (Sweden)

    Marina Bantzi

    2015-04-01

    Full Text Available In the present work, the synthesis of a hexasaccharide partial sequence of hyaluronan equipped with a terminal azido moiety is reported. This hexasaccharide can be used for the attachment on surfaces by means of click chemistry and after suitable deprotection for biophysical studies.

  8. Can hyaluronan injections augment deficient papillae at implant-supported crowns in the anterior maxilla?

    DEFF Research Database (Denmark)

    Bertl, Kristina; Gotfredsen, Klaus; Jensen, Simon S;

    2017-01-01

    OBJECTIVES: The present randomized controlled trial aimed to assess the effect of hyaluronan (HY) injections to augment deficient interproximal papillae at implant-supported crowns in the anterior maxilla. METHODS: Twenty-two patients with a deficient papilla in the anterior maxilla next to an im...

  9. Heparin prevents intracellular hyaluronan synthesis and autophagy responses in hyperglycemic dividing mesangial cells and activates synthesis of an extensive extracellular monocyte-adhesive hyaluronan matrix after completing cell division.

    Science.gov (United States)

    Wang, Aimin; Ren, Juan; Wang, Christina P; Hascall, Vincent C

    2014-03-28

    Growth-arrested rat mesangial cells (RMCs) at a G0/G1 interphase stimulated to divide in hyperglycemic medium initiate intracellular hyaluronan synthesis that induces autophagy/cyclin D3-induced formation of a monocyte-adhesive extracellular hyaluronan matrix after completing cell division. This study shows that heparin inhibits the intracellular hyaluronan synthesis and autophagy responses, but at the end of cell division it induces synthesis of a much larger extracellular monocyte-adhesive hyaluronan matrix. Heparin bound to RMC surfaces by 1 h, internalizes into the Golgi/endoplasmic reticulum region by 2 h, and was nearly gone by 4 h. Treatment by heparin for only the first 4 h was sufficient for its function. Streptozotocin diabetic rats treated daily with heparin showed similar results. Glomeruli in sections of diabetic kidneys showed extensive accumulation of autophagic RMCs, increased hyaluronan matrix, and influx of macrophages over 6 weeks. Hyaluronan staining in the glomeruli of heparin-treated diabetic rats was very high at week 1 and decreased to near control level by 6 weeks without any RMC autophagy. However, the influx of macrophages by 6 weeks was as pronounced as in diabetic glomeruli. The results are as follows: 1) heparin blocks synthesis of hyaluronan in intracellular compartments, which prevents the autophagy and cyclin D3 responses thereby allowing RMCs to complete cell division and sustain function; 2) interaction of heparin with RMCs in early G1 phase is sufficient to induce signaling pathway(s) for its functions; and 3) influxed macrophages effectively remove the hyaluronan matrix without inducing pro-fibrotic responses that lead to nephropathy and proteinurea in diabetic kidneys.

  10. Bioactive hyaluronan fragment (hexasaccharide) detects specific hexa-binding proteins in human breast and stomach cancer: possible role in tumorogenesis.

    Science.gov (United States)

    Srinivas, Prashanth; Kollapalli, Srinivas Prasad; Thomas, Anil; Mortha, Karuna Kumar; Banerjee, Shib Das

    2012-08-01

    Hyaluronan (HA) is a component of extracellular matrix that influences cell-proliferation, migration, development, regeneration, normal tissue remodeling, tissues undergoing malignancy and tumor cell interaction. The widespread occurrence of HA binding proteins, their involvement in tissue organization and the control of cellular behavior are well documented. The low molecular mass HA fragments can also induce a variety of biological events, including chemokine gene expression, transcription factor expression and angiogenesis. It is believed that these fragments are more potent in cellular activities than high molecular mass HA. In this study, we isolated the various fragments by gel permeation chromatography of hyaluronidase digested HA and characterized by fluoro assisted carbohydrate electrophoresis (FACE) and matrix assisted laser desorption ionization analysis (MALDI). Detection and distribution of cellular receptors in invasive tumor tissues for HA polymer and HA fragments were determined both by Western blot and histochemistry. The study demonstrated the overexpression of HA-hexa binding protein in human tumors of breast and stomach and its involvement in tumorogenesis.

  11. A practical and sensitive method of quantitating lymphangiogenesis in vivo.

    Science.gov (United States)

    Majumder, Mousumi; Xin, Xiping; Lala, Peeyush K

    2013-07-01

    To address the inadequacy of current assays, we developed a directed in vivo lymphangiogenesis assay (DIVLA) by modifying an established directed in vivo angiogenesis assay. Silicon tubes (angioreactors) were implanted in the dorsal flanks of nude mice. Tubes contained either growth factor-reduced basement membrane extract (BME)-alone (negative control) or BME-containing vascular endothelial growth factor (VEGF)-D (positive control for lymphangiogenesis) or FGF-2/VEGF-A (positive control for angiogenesis) or a high VEGF-D-expressing breast cancer cell line MDA-MD-468LN (468-LN), or VEGF-D-silenced 468LN. Lymphangiogenesis was detected superficially with Evans Blue dye tracing and measured in the cellular contents of angioreactors by multiple approaches: lymphatic vessel endothelial hyaluronan receptor-1 (Lyve1) protein (immunofluorescence) and mRNA (qPCR) expression and a visual scoring of lymphatic vs blood capillaries with dual Lyve1 (or PROX-11 or Podoplanin)/Cd31 immunostaining in cryosections. Lymphangiogenesis was absent with BME, high with VEGF-D or VEGF-D-producing 468LN cells and low with VEGF-D-silenced 468LN. Angiogenesis was absent with BME, high with FGF-2/VEGF-A, moderate with 468LN or VEGF-D and low with VEGF-D-silenced 468LN. The method was reproduced in a syngeneic murine C3L5 tumor model in C3H/HeJ mice with dual Lyve1/Cd31 immunostaining. Thus, DIVLA presents a practical and sensitive assay of lymphangiogenesis, validated with multiple approaches and markers. It is highly suited to identifying pro- and anti-lymphangiogenic agents, as well as shared or distinct mechanisms regulating lymphangiogenesis vs angiogenesis, and is widely applicable to research in vascular/tumor biology.

  12. Characterization of polyelectrolyte behavior of the polysaccharides chitosan, heparin, and hyaluronan, by light scattering and viscometry.

    Science.gov (United States)

    Boddohi, Soheil; Yonemura, Susan; Kipper, Matt

    2008-03-01

    This study on the polyelectrolyte behavior of polysaccharides in solution is motivated by our recent work in development of nanostructured polysaccharide-based surface coatings. Chitosan behaves as a weak polycation, and hyaluronan behaves as a weak polyanion, while heparin behaves as a strong polyanion. The ability to control the conformation of these polysaccharides in solution, by changing the solution ionic strength and pH may offer the opportunity to further tune the nanoscale features of polysaccharide-based surface coatings assembled from solution. In the work reported here, the solution conformation of these polymers is determined from gel permeation chromatography coupled to differential refractive index, light scattering, and viscometry detection. These results are related to the nanostructure of chitosan-heparin and chitosan-hyaluronan surface coatings based on polyelectrolyte multilayers.

  13. Isolation and characterization of the plasma hyaluronan-binding protein (PHBP) gene (HABP2).

    Science.gov (United States)

    Sumiya, J; Asakawa, S; Tobe, T; Hashimoto, K; Saguchi, K; Choi-Miura, N H; Shimizu, Y; Minoshima, S; Shimizu, N; Tomita, M

    1997-11-01

    PHBP is a novel human plasma hyaluronan-binding protein that shows significant homology in amino acid sequence to hepatocyte growth factor activator. Two overlapping clones that encode the human plasma hyaluronan-binding protein (PHBP) gene (HABP2) were isolated and characterized. The PHBP gene spans 35 kb and is composed of 13 exons from 37 to 1,394 bp in size with consensus splice sites. The gene's regulatory sequences contain putative promoter elements, but no typical TATA box. Some exons of this gene showed significant similarities to those of coagulation factor XII, tissue-type plasminogen activator, and urokinase genes in nucleotide length and in intron phasing. We also report the chromosome mapping of this gene by fluorescence in situ hybridization (FISH) using a genomic DNA fragment as a probe. The PHBP gene (HABP2) was located on chromosome 10q25-q26.

  14. Regulation of Non-Infectious Lung Injury, Inflammation, and Repair by the Extracellular Matrix Glycosaminoglycan Hyaluronan

    OpenAIRE

    Jiang, Dianhua; Liang, Jiurong; Noble, Paul W

    2010-01-01

    An important hallmark of tissue remodeling is the dynamic turnover of extracellular matrix (ECM). ECM performs a variety of functions in tissue repair including scaffold formation, modulation of fluid dynamics, and regulating cell behavior. During non-infectious tissue injury ECM degradation products are generated that acquire signaling functions not attributable to the native precursor molecules. Hyaluronan (HA) is a non-sulfated glycosaminoglycan which is produced in great abundance followi...

  15. High molecular weight hyaluronan for treatment of chronic shoulder pain associated with glenohumeral arthritis

    OpenAIRE

    Weil AJ

    2011-01-01

    Arnold J WeilNon-Surgical Orthopedics PC, Marietta, GA, USABackground: There is insufficient evidence to determine whether intra-articular injections may be effective for treatment of glenohumeral osteoarthritis. Euflexxa® (high molecular weight hyaluronate), a bioengineered high molecular weight hyaluronan, has been shown to be a safe and effective treatment for patients with knee osteoarthritis. There is also support for the use of hyaluronate injection for the treatment of chronic ...

  16. Charged Triazole Cross-Linkers for Hyaluronan-Based Hybrid Hydrogels

    Directory of Open Access Journals (Sweden)

    Maike Martini

    2016-09-01

    Full Text Available Polyelectrolyte hydrogels play an important role in tissue engineering and can be produced from natural polymers, such as the glycosaminoglycan hyaluronan. In order to control charge density and mechanical properties of hyaluronan-based hydrogels, we developed cross-linkers with a neutral or positively charged triazole core with different lengths of spacer arms and two terminal maleimide groups. These cross-linkers react with thiolated hyaluronan in a fast, stoichiometric thio-Michael addition. Introducing a positive charge on the core of the cross-linker enabled us to compare hydrogels with the same interconnectivity, but a different charge density. Positively charged cross-linkers form stiffer hydrogels relatively independent of the size of the cross-linker, whereas neutral cross-linkers only form stable hydrogels at small spacer lengths. These novel cross-linkers provide a platform to tune the hydrogel network charge and thus the mechanical properties of the network. In addition, they might offer a wide range of applications especially in bioprinting for precise design of hydrogels.

  17. Hyaluronan- and RNA-binding deubiquitinating enzymes of USP17 family members associated with cell viability

    Directory of Open Access Journals (Sweden)

    Kim Dongku

    2006-11-01

    Full Text Available Abstract Background Protein degradation by the ubiquitin system plays a crucial role in numerous cellular signaling pathways. Deubiquitination, a reversal of ubiquitination, has been recognized as an important regulatory step in the ubiquitin-dependent degradation pathway. Results While identifying putative ubiquitin specific protease (USP enzymes that contain a conserved Asp (I domain in humans, 4 USP17 subfamily members, highly homologous to DUB-3, have been found (USP17K, USP17L, USP17M, and USP17N, from human chorionic villi. Expression analysis showed that USP17 transcripts are highly expressed in the heart, liver, and pancreas and are expressed moderately in various human cancerous cell lines. Amino acid sequence analysis revealed that they contain the highly conserved Cys, His, and Asp domains which are responsible for the deubiquitinating activity. Biochemical enzyme assays indicated that they have deubiquitinating activity. Interestingly, the sequence analysis showed that these proteins, with exception of USP17N, contain the putative hyaluronan/RNA binding motifs, and cetylpyridinium chloride (CPC-precipitation analysis confirmed the association between these proteins and intracellular hyaluronan and RNA. Conclusion Here, we report that the overexpression of these proteins, with exception of USP17N, leads to apoptosis, suggesting that the hyaluronan and RNA binding motifs in these enzymes play an important role in regulating signal transduction involved in cell death.

  18. Biomimetic hemocompatible coatings through immobilization of hyaluronan derivatives on metal surfaces.

    Science.gov (United States)

    Thierry, Benjamin; Winnik, Françoise M; Merhi, Yahye; Griesser, Hans J; Tabrizian, Maryam

    2008-10-21

    Biomimetic coatings offer exciting options to modulate the biocompatibility of biomaterials. The challenge is to create surfaces that undergo specific interactions with cells without promoting nonspecific fouling. This work reports an innovative approach toward biomimetic surfaces based on the covalent immobilization of a carboxylate terminated PEGylated hyaluronan (HA-PEG) onto plasma functionalized NiTi alloy surfaces. The metal substrates were aminated via two different plasma functionalization processes. Hyaluronan, a natural glycosaminoglycan and the major constituent of the extracellular matrix, was grafted to the substrates by reaction of the surface amines with the carboxylic acid terminated PEG spacer using carbodiimide chemistry. The surface modification was monitored at each step by X-ray photoelectron spectroscopy (XPS). HA-immobilized surfaces displayed increased hydrophilicity and reduced fouling, compared to bare surfaces, when exposed to human platelets (PLT) in an in vitro assay with radiolabeled platelets (204.1 +/- 123.8 x 10 (3) PLT/cm (2) vs 538.5 +/- 100.5 x 10 (3) PLT/cm (2) for bare metal, p surfaces were successfully created as demonstrated by XPS chemical imaging. The bioactive surfaces described present unique features, which result from the synergy between the intrinsic biological properties of hyaluronan and the chemical composition and morphology of the polymer layer immobilized on a metal surface.

  19. receptores

    Directory of Open Access Journals (Sweden)

    Salete Regina Daronco Benetti

    2006-01-01

    Full Text Available Se trata de un estudio etnográfico, que tuvo lo objetivo de interpretar el sistema de conocimiento y del significado atribuidos a la sangre referente a la transfusión sanguínea por los donadores y receptores de un banco de sangre. Para la colecta de las informaciones se observaron los participantes y la entrevista etnográfica se realizó el análisis de dominio, taxonómicos y temáticos. Los dominios culturales fueron: la sangre es vida: fuente de vida y alimento valioso; creencias religiosas: fuentes simbólicas de apoyos; donación sanguínea: un gesto colaborador que exige cuidarse, gratifica y trae felicidad; donación sanguínea: fuente simbólica de inseguridad; estar enfermo es una condición para realizar transfusión sanguínea; transfusión sanguínea: esperanza de vida; Creencias populares: transfusión sanguínea como riesgo para la salud; donadores de sangre: personas benditas; donar y recibir sangre: como significado de felicidad. Temática: “líquido precioso que origina, sostiene, modifica la vida, provoca miedo e inseguridad”.

  20. Dynamics of hyaluronan, CD44, and inflammatory cells in the rat kidney after ischemia/reperfusion injury.

    Science.gov (United States)

    Declèves, Anne-Emilie; Caron, Nathalie; Nonclercq, Denis; Legrand, Alexandre; Toubeau, Gérard; Kramp, Ronald; Flamion, Bruno

    2006-07-01

    Ischemia/reperfusion (I/R) injury in the kidney involves hemodynamic and cellular dysfunctions as well as leukocyte infiltration. Functional recovery occurs via cell proliferation and/or migration. To determine the roles of hyaluronan (HA) and its main receptor CD44 in renal postischemic processes, we compared their localization and expression with that of neutrophils, macrophages, and PCNA-positive (regenerative) cells as characterized by immunohistochemistry, up to 28 days after I/R in uninephrectomized rats. Observations covered all kidney zones, i.e. cortex (C), outer and inner stripes of outer medulla (OSOM, ISOM), and inner medulla (IM). In controls, HA was localized to the interstitium of IM and ISOM, and CD44 was mostly present on the basolateral membranes of collecting ducts in ISOM, the thin descending limb of Henle's loop and macula densa cells. After I/R, HA and CD44 staining appeared in C and OSOM at 12 h and persisted throughout the regenerative period, i.e. until day 7. Thereafter, they regressed but remained associated with remodeling areas. CD44 expression was found de novo on the apical pole of regenerating, not fully differentiated tubular cells and on some interstitial cells. It was prominent on all infiltrating neutrophils, as soon as 2 h post-I/R, and on 30% of the macrophages, including those in late HA-rich inflammatory granulomas. CD44 is probably involved in early leukocyte infiltration, in tubular regeneration, and in macrophage activity, while HA modifies the physico-chemical environment of interstitial and migrating cells. Based on its presence in remodeling areas, the HA-CD44 pair may be implicated in persistent postichemic inflammation as observed in chronic allograft nephropathy.

  1. Superovulation of beef cattle with a split-single intramuscular administration of Folltropin-V in two concentrations of hyaluronan.

    Science.gov (United States)

    Tríbulo, Andrés; Rogan, Dragan; Tríbulo, Humberto; Tríbulo, Ricardo; Mapletoft, Reuben J; Bó, Gabriel A

    2012-05-01

    Three experiments were designed to evaluate the superovulatory response of beef cows following two intramuscular (IM) administrations 48 h apart of Folltropin-V diluted in reduced concentrations of hyaluronan (Split-single IM administrations; Experiment 1-300 mg Folltropin-V on the first day and 100 mg 48 h later; Experiment 2-200 mg Folltropin-V on the first day and 100 mg 48 h later). In Experiments 1 and 2, superovulatory response and ova embryo/embryo production did not differ between donors receiving twice daily IM of Folltropin-V over 4 days and those given a Split-single IM administration of Folltropin-V diluted in 10 mg/mL hyaluronan solution. Experiment 3 compared Split-single IM administration of Folltropin-V diluted in two hyaluronan concentrations (5 or 10 mg/mL) with Folltropin-V diluted in saline and administered twice-daily over 4 days. Beef cows (17 Angus and 12 Simmental) were randomly assigned to one of three treatment groups to be superstimulated three times in a cross-over design, so that all cows received all treatments. A total dose of 300 mg Folltropin-V was divided into twice-daily IM over 4 days, or in two IM treatment 48 h apart (200 mg on first day and 100 mg 48 h later) in the hyaluronan groups. Mean (± SEM) numbers of transferable embryos did not differ among treatment groups (Control: 4.0 ± 0.8; 10 mg/mL hylauronan: 5.0 ± 0.9; 5 mg/mL hyaluronan: 6.1 ± 1.3). We concluded that the Split-single IM administration of Folltropin-V diluted in either concentration of hyaluronan resulted in a comparable superovulatory response to the traditional twice-daily protocol.

  2. A hyaluronan-based nerve guide : in vitro cytotoxicity, subcutaneous tissue reactions, and degradation in the rat

    NARCIS (Netherlands)

    Jansen, K; van Wachem, PB; Nicolai, JPA; de Leij, LFMH; van Luyn, MJA; van der Werf, J.F.A.

    2004-01-01

    We investigated possible cytotoxic effects, biocompatibility, and degradation of a hyaluronan-based conduit for peripheral nerve repair. We subjected the conduits to an in vitro fibroblast cytotoxicity test and concluded that the conduits were not cytotoxic. Subsequently, we implanted the conduits s

  3. Hyaluronan, neural stem cells and tissue reconstruction after acute ischemic stroke.

    Science.gov (United States)

    Moshayedi, Pouria; Carmichael, S Thomas

    2013-01-01

    Focal stroke is a disabling disease with lifelong sensory, motor and cognitive impairments. Given the paucity of effective clinical treatments, basic scientists are developing novel options for protection of the affected brain and regeneration of lost tissue. Tissue bioengineering and stem/progenitor cell treatments have both been individually pursued for stroke neural repair therapies, with some benefit in tissue recovery. Emerging directions in stroke neural repair approaches combine these two therapies to use biopolymers with stem/progenitor transplants to promote greater cell survival in the transplant and directed delivery of bioactive molecules to the transplanted cells and the adjacent injured tissue. In this review the background literature on a combined use of neural stem/progenitor cells encapsulated in hyaluronan gels is discussed and the way this therapeutic approach can affect the important processes involved in brain tissue reconstruction, such as angiogenesis, axon regeneration, neural differentiation and inflammation is clarified. The glycosaminoglycan hyaluronan can optimize those processes and be employed in a successful neural tissue engineering approach.

  4. Design of benzimidazole- and benzoxazole-2-thione derivatives as inhibitors of bacterial hyaluronan lyase.

    Science.gov (United States)

    Braun, Stephan; Botzki, Alexander; Salmen, Sunnhild; Textor, Christian; Bernhardt, Günther; Dove, Stefan; Buschauer, Armin

    2011-09-01

    Bacterial hyaluronan lyases (Hyal) degrade hyaluronan, an important component of the extracellular matrix, and are involved in microbial spread. Hyal inhibitors may serve as tools to study the role of the enzyme, its substrates and products in the course of bacterial infections. Moreover, such enzyme inhibitors are potential candidates for antibacterial combination therapy. Based on crystal structures of Streptococcus pneumoniae Hyal in complex with a hexasaccharide substrate and with different inhibitors, 1-acylated benzimidazole-2-thiones and benzoxazole-2-thiones were derived as new leads for the inhibition of Streptococcus agalactiae strain 4755 Hyal. Structure-based optimization led to N-(3-phenylpropionyl)benzoxazole-2-thione, one of the most potent compounds known to date (IC(50) values: 24 μM at pH 7.4, 15 μM at pH 5). Among the 27 new derivatives, other N-acylated benzimidazoles and benzoxazoles are just as active at pH 7.4, but not at pH 5. The results support a binding mode characterized by interactions with residues in the catalytic site and with a hydrophobic patch.

  5. Survival of cord blood haematopoietic stem cells in a hyaluronan hydrogel for ex vivo biomimicry.

    Science.gov (United States)

    Demange, Elise; Kassim, Yusra; Petit, Cyrille; Buquet, Catherine; Dulong, Virginie; Cerf, Didier Le; Buchonnet, Gérard; Vannier, Jean-Pierre

    2013-11-01

    Haematopoietic stem cells (HSCs) and haematopoietic progenitor cells (HPCs) grow in a specified niche in close association with the microenvironment, the so-called 'haematopoietic niche'. Scaffolds have been introduced to overcome the liquid culture limitations, mimicking the presence of the extracellular matrix (ECM). In the present study the hyaluronic acid scaffold, already developed in the laboratory, has been used for the first time to maintain long-term cultures of CD34⁺ haematopoietic cells obtained from human cord blood. One parameter investigated was the impact on ex vivo survival of CD34⁺ cord blood cells (CBCs) on the hyaluronic acid surface, immobilized with peptides containing the RGD motif. This peptide was conjugated by coating the hyaluronan hydrogel and cultured in serum-free liquid phase complemented with stem cell factor (SCF), a commonly indispensable cytokine for haematopoiesis. Our work demonstrated that these hyaluronan hydrogels were superior to traditional liquid cultures by maintaining and expanding the HPCs without the need for additional cytokines, and a colonization of 280-fold increment in the hydrogel compared with liquid culture after 28 days of ex vivo expansion. Copyright © 2012 John Wiley & Sons, Ltd.

  6. New E-beam-initiated hyaluronan acrylate cryogels support growth and matrix deposition by dermal fibroblasts.

    Science.gov (United States)

    Thönes, S; Kutz, L M; Oehmichen, S; Becher, J; Heymann, K; Saalbach, A; Knolle, W; Schnabelrauch, M; Reichelt, S; Anderegg, U

    2017-01-01

    Cryogels made of components of natural extracellular matrix components are potent biomaterials for bioengineering and regenerative medicine. Human dermal fibroblasts are key cells for tissue replacement during wound healing. Thus, any biomaterial for wound healing applications should enable growth, differentiation and matrix synthesis by these cells. Cryogels are highly porous scaffolds consisting of a network of interconnected pores. Here, we used a novel group of cryogels generated from acrylated hyaluronan where the polymerization was initiated by accelerated electrons (E-beam). This novel procedure omits any toxic polymerization initiators and results in sterile, highly elastic scaffolds with adjustable pore size, excellent swelling and low flow resistance properties. We show that these cryogels are effective 3D-substrates for long-term cultures of human dermal fibroblasts in vitro. The cells proliferate for at least 28days throughout the cryogels and deposit their own matrix in the pores. Moreover, key modulators of dermal fibroblasts during wound healing like TGFβ and PDGF efficiently stimulated the expression of wound healing-relevant genes. In conclusion, electron beam initiated cryogels of acrylated hyaluronan represent a functional and cell compatible biomaterial that could be adapted for special wound healing applications by further functionalization. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Rodlike Complexes of a Polyelectrolyte (Hyaluronan) and a Protein (Lysozyme) observed by SANS

    CERN Document Server

    Boué, François; Cousin, Fabrice; Grillo, Isabelle; Morfin, Isabelle; 10.1021/bm100861g

    2012-01-01

    We study by Small Angle Neutron Scattering (SANS) the structure of Hyaluronan -Lysozyme complexes. Hyaluronan (HA) is a polysaccharide of 9 nm intrinsic persistence length that bears one negative charge per disaccharide monomer (Mmol = 401.3 g/mol); two molecular weights, Mw = 6000 and 500 000 Da were used. The pH was adjusted at 4.7 and 7.4 so that lysozyme has a global charge of +10 and + 8 respectively. The lysozyme concentration was varied from 3 to 40 g/L, at constant HA concentration (10 g/L). At low protein concentration, samples are monophasic and SANS experiments reveal only fluctuations of concentration although, at high protein concentration, clusters are observed by SANS in the dense phase of the diphasic samples. In between, close to the onset of the phase separation, a distinct original scattering is observed. It is characteristic of a rod-like shape, which could characterize "single" complexes involving one or a few polymer chains. For the large molecular weight (500 000) the rodlike rigid doma...

  8. Targeted Delivery of Hyaluronan-Immobilized Magnetic Ceramic Nanocrystals.

    Science.gov (United States)

    Wu, Hsi-Chin; Wang, Tzu-Wei; Hsieh, Shun-Yu; Sun, Jui-Sheng; Kang, Pei-Leun

    2016-01-01

    Effective cancer therapy relies on delivering the therapeutic agent precisely to the target site to improve the treatment outcome and to minimize side effects. Although surgery, chemotherapy, and radiotherapy are the standard methods commonly used in clinics, hyperthermia has been developed as a new and promising strategy for cancer therapy. In this study, magnetic bioceramic hydroxyapatite (mHAP) nanocrystals have been developed as heat mediator for intracellular hyperthermia. Hyaluronic acid (HA) modified mHAP nanocrystals are synthesized by a wet chemical precipitation process to achieve active targeting. The results demonstrate that the HA targeting moiety conjugated by a poly(ethylene glycol) (PEG) spacer arm is successfully immobilized on the surface of mHAP. The HA-modified mHAP possesses relatively good biocompatibility, an adequate biodegradation rate and superparamagnetic properties. The HA-modified mHAP could be localized and internalized into HA receptor-overexpressed malignant cells (e.g., MDA-MB-231 cell) and used as the heat generating agent for intracellular hyperthermia. The results from this study indicate that biocompatible HA-modified mHAP shows promise as a novel heat mediator and a specific targeting nanoagent for intracellular hyperthermia cancer therapy.

  9. Effect of molecular weight and concentration of hyaluronan on cell proliferation and osteogenic differentiation in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Ningbo, E-mail: curl-zhao@163.com; Wang, Xin, E-mail: 394041230@qq.com; Qin, Lei, E-mail: qinlei30@126.com; Guo, Zhengze, E-mail: zhzeguo@163.com; Li, Dehua, E-mail: lidehuafmmu@163.com

    2015-09-25

    Hyaluronan (HA), the simplest glycosaminoglycan and a major component of the extracellular matrix, exists in various tissues. It is involved in some critical biological procedures, including cellular signaling, cell adhesion and proliferation, and cell differentiation. The effect of molecular weight (MW) and concentration of HA on cell proliferation and differentiation was controversial. In this study, we investigated the effect of MW and concentration of HA on the proliferation and osteogenic differentiation of rabbit bone marrow-derived stem cells in vitro. Results showed that high MW HA decreased the cell adhesion rate in a concentration-dependant manner. The cell adhesion rate was decreased by increasing MW of HA. Cell proliferation was significantly enhanced by low MW HA (P < 0.05). The factorial analysis indicated that MW and concentration had an interactive effect on the cell adhesion rate and cell proliferation (P < 0.05). High MW HA increased the mRNA expressions of ALP, RUNX-2 and OCN. The higher the MW was, the higher the mRNA expressions were. The factorial analysis indicated that MW and concentration had an interactive effect on ALP mRNA expression (P < 0.05). HA of higher MW and higher concentration promoted bone formation. These findings provide some useful information in understanding the mechanism underlying the effect of MW and concentration of HA on cell proliferation and differentiation. - Highlights: • Effect of hyaluronan on cell proliferation and differentiation is evaluated in vitro. • Hyaluronan of low molecular weight increases cell proliferation. • Hyaluronan of high molecular weight promotes cell osteogenic differentiation. • Molecular weight and concentration of hyaluronan show interactive effect.

  10. The effect of different doses of hyaluronan on sperm morphology, motility, vitality and fertilization capability in mouse

    Directory of Open Access Journals (Sweden)

    S. Sayadi

    2006-07-01

    Full Text Available Background: Hyaluronan has an important role on the permeability and motility of sperm and the interaction of gametes and these can play a considerable role on the fertility rate. Therefore, in this study, we assessed the effect of different doses of hyaluronan on the morphology, motility, vitality and fertility rate of mice. Methods: We used 40 mice (6-8 week in this study which twenty of them were male and the rest were female. The sperm of each male mouse were divided into four groups. The group 1 (control: They were maintained in RPMI media without any hyaluronan supplementation for 2 hour. Hyaluronan with the doses of 750, 1000 and 1250 µg/ml were added into RPMI media in groups 2, 3 and 4, respectively. After 2 hour. incubation, the numbers of sperms were assessed, using haemocytometer. Also, their morphology with papanicolaeu staining and their vitality with Eosin B dye were assessed. As well as sperms motility measured under inverted microscope by observation and fertility rate evaluated after routine IVF by counting two-cell stage embryos. Results: Our results demonstrated that, the dose of 750 µ g/ml has the greatest effect on the motility, vitality and fertility rate of sperms. The effect of dose of 1000 µ g/ml also was positive on them. On the other hand, none of these doses had any effect on sperm morphology. Conclusion: Hyaluronan may have an influence on motility, vitality and fertility rate of sperms and the dose of 750µ g/ml had a significant effect on these factors.

  11. Self-reinforcement and protein sustained delivery of hyaluronan hydrogel by tailoring a dually cross-linked network

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Chunhong; Xu, Guoguang; Wang, Xinghui [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Tu, Mei; Zeng, Rong; Rong, Jianhua [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China); Zhao, Jianhao, E-mail: jhzhao@jnu.edu.cn [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China)

    2015-01-01

    A series of self-reinforcing hyaluronan hydrogels were developed to improve mechanical properties and protein sustained delivery thanks to a dually cross-linked network. Hyaluronan gel particles (HGPs, 1–5 μm in diameter) with different cross-linking densities, i.e. HGPs-1.5, HGPs-3 and HGPs-15, were prepared in an inverse emulsion system and used as the reinforcing phase after glycidyl methacrylation, while glycidyl methacrylated hyaluronan with a substitution degree of 45.2% was synthesized as the matrix phase. These two phases were cross-linked under ultraviolet irradiation to form self-reinforcing hyaluronan hydrogels (srHAs) that showed typical cross-linked structure of HGPs connecting the matrix phase by cross-section observation. In comparison to hyaluronan bulk gels and their blends with HGPs, srHAs distinctly enhanced the mechanical properties and BSA long-term sustained delivery, especially srHA-1.5 showed the highest compressive modulus of 220 ± 15 kPa and the slowest BSA delivery (67% release at 14 d). The 3T3 fibroblast cell culture showed that all the srHAs had no cytotoxicity. - Highlights: • New self-reinforcing HA hydrogels with a dually cross-linked network were developed. • Self-reinforcing HA hydrogels greatly enhanced the mechanical properties. • Self-reinforcing HA hydrogels prolonged the sustained delivery of BSA. • The self-reinforcing mechanism and BSA diffusion mechanism were discussed. • Self-reinforcing HA hydrogels had no cytotoxicity to 3T3 fibroblast cells.

  12. Molecular evolution of the hyaluronan synthase 2 gene in mammals: implications for adaptations to the subterranean niche and cancer resistance.

    Science.gov (United States)

    Faulkes, Christopher G; Davies, Kalina T J; Rossiter, Stephen J; Bennett, Nigel C

    2015-05-01

    The naked mole-rat (NMR) Heterocephalus glaber is a unique and fascinating mammal exhibiting many unusual adaptations to a subterranean lifestyle. The recent discovery of their resistance to cancer and exceptional longevity has opened up new and important avenues of research. Part of this resistance to cancer has been attributed to the fact that NMRs produce a modified form of hyaluronan--a key constituent of the extracellular matrix--that is thought to confer increased elasticity of the skin as an adaptation for living in narrow tunnels. This so-called high molecular mass hyaluronan (HMM-HA) stems from two apparently unique substitutions in the hyaluronan synthase 2 enzyme (HAS2). To test whether other subterranean mammals with similar selection pressures also show molecular adaptation in their HAS2 gene, we sequenced the HAS2 gene for 11 subterranean mammals and closely related species, and combined these with data from 57 other mammals. Comparative screening revealed that one of the two putatively important HAS2 substitutions in the NMR predicted to have a significant effect on hyaluronan synthase function was uniquely shared by all African mole-rats. Interestingly, we also identified multiple other amino acid substitutions in key domains of the HAS2 molecule, although the biological consequences of these for hyaluronan synthesis remain to be determined. Despite these results, we found evidence of strong purifying selection acting on the HAS2 gene across all mammals, and the NMR remains unique in its particular HAS2 sequence. Our results indicate that more work is needed to determine whether the apparent cancer resistance seen in NMR is shared by other members of the African mole-rat clade. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  13. Antioxidant effect of hyaluronan on polymorphonuclear leukocyte-derived reactive oxygen species is dependent on its molecular weight and concentration and mainly involves the extracellular space

    Directory of Open Access Journals (Sweden)

    Rafał Krasiński

    2009-05-01

    Full Text Available Introduction: Hyaluronan (HA, a component of the extracellular matrix, may regulate immune cell functions through its interactions with cellular receptors. Besides its effect on cytokine and chemokine production, its antioxidant properties have been described. However, the mechanisms of this are not fully elucidated. The aim of this study was to evaluate the relationship between HA concentration and molecular weight and its antioxidant properties towards human neutrophils. Also assessed was whether the antioxidant effect of HA is connected with a reduction in intracellular oxygen potential, which could indicate its direct effect on neutrophil respiratory burst.Materials/Methods: The relationship between HA’s antioxidant properties and its concentration and molecular weight was assessed by the luminol-enhanced chemiluminescence method (CL. To evaluate the effect of HA on intracellular oxygen potential selectively, the dihydrorhodamine 123 (DHR123 flow cytometric method was used.Results: Reduction of both HA molecular weight and its concentration decreased its antioxidant properties in the CL method. A selective effect of HA on intracellular oxygen potential measured by the DHR123 method was not shown.Conclusions: The antioxidant properties of HA are related to both its molecular weight and its concentration. The lack of an antioxidant effect of HA in the DHR123 test compared with a significant reduction in CL values at the same HA concentration suggests that HA acts mainly as a chemical ROI scavenger in the extracellular space.

  14. Synthesis and characterization of collagen/hyaluronan/chitosan composite sponges for potential biomedical applications.

    Science.gov (United States)

    Lin, Yen-Chih; Tan, Fa-Jui; Marra, Kacey G; Jan, Shyh-Shyan; Liu, Deng-Cheng

    2009-09-01

    Cells, scaffolds and growth factors are three main components of a tissue-engineered construct. Collagen type I, a major protein of the extracellular matrix (ECM) in mammals, is a suitable scaffold material for regeneration. Another important constituent of the ECM, hyaluronic acid (hyaluronan, HA), has been used for medical purposes due to its hydrogel properties and biodegradability. Chitosan is a linear polysaccharide comprised of beta1- to beta4-linked d-glucosamine residues, and its potential as a biomaterial is based on its cationic nature and high charge density in solution. This study was conducted to evaluate the characteristics of scaffolds composed of different ratios of type I comb collagen and chitosan with added HA in order to obtain the optimum conditions for the manufacture of collagen-hyaluronan-chitosan (Col-HA-Ch; comprising collagen, HA and chitosan mixed in different ratios: 10:1:0, Col10HACh0; 9:1:1, Col9HACh1; 8:1:2, Col8HACh2; 7:1:3, Col7HACh3; 6:1:4, Col6HACh4; and 5:1:5, Col5HACh5) composite porous scaffolds. Microstructural observation of the composite scaffolds was performed using scanning electron microscopy. The mean pore diameters ranged from 120 to 182microm and decreased as the chitosan composition increased. All scaffolds showed high pore interconnectivity. Swelling ratio measurements showed that all specimens could bind 35- to 40-fold of physiological fluid and still maintain their form and stability. For tensile strength, the optimal ratio of collagen and chitosan was 9:1. Thermal stability was investigated using a differential scanning calorimeter and showed that Col5HACh5 and Col6HACh4 were significantly more stable than the other groups. In enzymatic sensitivity, a steady increase in the biostability of the scaffolds was achieved as the chitosan concentration was increased. In biocompatibility testing, the proliferation of the fibroblasts cultured in Co-HA-Ch tri-copolymer scaffolds was high. Overall, we observed the 9

  15. Low molecular weight hyaluronan activates cytosolic phospholipase A2α and eicosanoid production in monocytes and macrophages.

    Science.gov (United States)

    Sokolowska, Milena; Chen, Li-Yuan; Eberlein, Michael; Martinez-Anton, Asuncion; Liu, Yueqin; Alsaaty, Sara; Qi, Hai-Yan; Logun, Carolea; Horton, Maureen; Shelhamer, James H

    2014-02-14

    Hyaluronan (HA) is the major glycosaminoglycan in the extracellular matrix. During inflammation, there is an increased breakdown of HA, resulting in the accumulation of low molecular weight (LMW) HA and activation of monocytes and macrophages. Eicosanoids, derived from the cytosolic phospholipase A2 group IVA (cPLA2α) activation, are potent lipid mediators also attributed to acute and chronic inflammation. The aim of this study was to determine the effect of LMW HA on cPLA2α activation, arachidonic acid (AA) release, and subsequent eicosanoid production and to examine the receptors and downstream mechanisms involved in these processes in monocytes and differently polarized macrophages. LMW HA was a potent stimulant of AA release in a time- and dose-dependent manner, induced cPLA2α, ERK1/2, p38, and JNK phosphorylation, as well as activated COX2 expression and prostaglandin (PG) E2 production in primary human monocytes, murine RAW 264.7, and wild-type bone marrow-derived macrophages. Specific cPLA2α inhibitor blocked HA-induced AA release and PGE2 production in all of these cells. Using CD44, TLR4, TLR2, MYD88, RHAMM or STAB2 siRNA-transfected macrophages and monocytes, we found that AA release, cPLA2α, ERK1/2, p38, and JNK phosphorylation, COX2 expression, and PGE2 production were activated by LMW HA through a TLR4/MYD88 pathway. Likewise, PGE2 production and COX2 expression were blocked in Tlr4(-/-) and Myd88(-/-) mice, but not in Cd44(-/-) mice, after LMW HA stimulation. Moreover, we demonstrated that LMW HA activated the M1 macrophage phenotype with the unique cPLA2α/COX2(high) and COX1/ALOX15/ALOX5/LTA4H(low) gene and PGE2/PGD2/15-HETE(high) and LXA4(low) eicosanoid profile. These findings reveal a novel link between HA-mediated inflammation and lipid metabolism.

  16. Anti-inflammatory effects of hyaluronan in arthritis therapy: Not just for viscosity

    Directory of Open Access Journals (Sweden)

    Kayo Masuko

    2009-04-01

    Full Text Available Kayo Masuko1, Minako Murata2, Kazuo Yudoh2, Tomohiro Kato1, Hiroshi Nakamura31Department of Biochemistry; 2Institute of Medical Science, St. Marianna University School of Medicine, Kawasaki-shi, Kanagawa, Japan; 3Department of Joint Disease and Rheumatism, Nippon Medical School, Bunkyo-ku, Tokyo, JapanAbstract: Hyaluronic acid (HA has been widely used for viscosupplementation of diseased or aged articular joints. However, recent investigations have revealed the active anti-inflammatory or chondroprotective effect of HA, suggesting its potential role in attenuation of joint damage. In particular, interactions between HA and other inflammatory mediators are attracting interest. This review summarizes several aspects of recent investigations of the anti-inflammatory effects of HA in arthritis.Keywords: hyaluronan, inflammation, chondroprotection

  17. Effect of hyaluronan on osteogenic differentiation of porcine bone marrow stromal cells in vitro

    DEFF Research Database (Denmark)

    Zou, Lijin; Zou, Xuenong; Chen, Li

    2007-01-01

    Hyaluronan (HA) plays a predominant role in tissue morphogenesis, cell migration, proliferation, and cell differentiation. The aims of the present study were to investigate whether (i) prolonged presence of high concentration (4.0 mg/mL) 800 KDa HA and (ii) pretreatment with HA can modify...... osteogenic differentiation of pig bone marrow stromal cells (pBMSC). Cell proliferation and mineralization were measured. Expression of differentiation-related genes was evaluated by means of real-time reverse transcription polymerase chain reaction (RT-PCR). HA increased cell proliferation on day 7. HA...... decreased the basal level of bone-related gene expression and increased the basal level of sox9 marginally during 7-day pretreatment with HA. HA increased calcium deposit on day 21. cbfa1, ALP, and type 1alpha collagen (Col1) expression was increased when pBMSC were cultivated in osteogenic medium, whereas...

  18. Increased Levels of Type I and III Collagen and Hyaluronan in Scleroderma Skin

    DEFF Research Database (Denmark)

    Søndergaard, Klaus; Heickendorff, Lene; L, Risteli

    1997-01-01

    The aminoterminal propeptide of type III procollagen (PIIINP) and the carboxyterminal propeptide of type I procollagen (PICP) and hyaluronan (HA) were measured in plasma and suction blister fluid from 13 systemic sclerosis patients and 11 healthy volunteers. Suction blisters and skin biopsies were...... from the transition zone between normal skin and scleroderma, and uninvolved abdominal skin of patients. The median value of suction blister PIIINP from the transition zone was 38% higher than suction blister PIIINP from uninvolved skin. PIIINP was localized to the dermis by immunohistochemical...... techniques. PICP and HA levels in blisters from the transition zone were 87% and 53%, respectively, above the levels measured in uninvolved skin. Furthermore, PICP and HA blister levels from the transition zone were 67% and 63%, respectively, higher than the levels measured in healthy volunteers. In plasma...

  19. Growth promoting effect of hyaluronan synthesis promoting substances on Japanese eel leptocephali.

    Directory of Open Access Journals (Sweden)

    Yutaka Kawakami

    Full Text Available Hyaluronans (HAs are glycosaminoglycans produced in the bodies of Anguilliform and Elopiform leptocephali, and play a role in metabolic energy. In mammals, HA synthesis-promoting substances (HASPS up-regulate the expression of HA synthase (HAS and increase the amount of HA in the body. In this study, Japanese eel leptocephali were fed a HASPS containing diet. We analyzed HAS1s and HAS2 expression, HA content, and their influence on growth. HASPS extracted from Grifola frondosa promoted HAS1s and HAS2 mRNA and HA content. Other than mammals, these results are first reported in vertebrate. Moreover, HASPS extracted from G. frondosa promoted leptocephalus growth. The relationship between growth and HA in the leptocephali is not yet clear. However, based on our results we hypothesize that HA is involved in the storage of energy, which is metabolized to sugars when needed for metabolic energy.

  20. Increased Levels of Type I and III Collagen and Hyaluronan in Scleroderma Skin

    DEFF Research Database (Denmark)

    Søndergaard, Klaus; Heickendorff, Lene; L, Risteli

    1997-01-01

    The aminoterminal propeptide of type III procollagen (PIIINP) and the carboxyterminal propeptide of type I procollagen (PICP) and hyaluronan (HA) were measured in plasma and suction blister fluid from 13 systemic sclerosis patients and 11 healthy volunteers. Suction blisters and skin biopsies were...... from the transition zone between normal skin and scleroderma, and uninvolved abdominal skin of patients. The median value of suction blister PIIINP from the transition zone was 38% higher than suction blister PIIINP from uninvolved skin. PIIINP was localized to the dermis by immunohistochemical...... techniques. PICP and HA levels in blisters from the transition zone were 87% and 53%, respectively, above the levels measured in uninvolved skin. Furthermore, PICP and HA blister levels from the transition zone were 67% and 63%, respectively, higher than the levels measured in healthy volunteers. In plasma...

  1. Hypochlorite-mediated fragmentation of hyaluronan, chondroitin sulfates, and related N-acetyl glycosamines

    DEFF Research Database (Denmark)

    Rees, Martin D; Hawkins, Clare Louise; Davies, Michael Jonathan

    2003-01-01

    Myeloperoxidase released from activated phagocytes reacts with H(2)O(2) in the presence of chloride ions to give hypochlorous acid. This oxidant has been implicated in the fragmentation of glycosaminoglycans, such as hyaluronan and chondroitin sulfates. In this study it is shown that reaction......, product formation via this mechanism is near quantitative with respect to chloramide loss. Analogous reactions with the glycosaminoglycans result in selective fragmentation at disaccharide intervals, as evidenced by the formation of "ladders" on gels; this selectivity is less marked under atmospheric...... oxygen concentrations than under anoxic conditions, due to competing peroxyl radical reactions. As the extracellular matrix plays a key role in mediating cell adhesion, growth, activation, and signaling, such HOCl-mediated glycosaminoglycan fragmentation may play a key role in disease progression...

  2. Hyaluronan binding motifs of USP17 and SDS3 exhibit anti-tumor activity.

    Directory of Open Access Journals (Sweden)

    Suresh Ramakrishna

    Full Text Available BACKGROUND: We previously reported that the USP17 deubiquitinating enzyme having hyaluronan binding motifs (HABMs interacts with human SDS3 (suppressor of defective silencing 3 and specifically deubiquitinates Lys-63 branched polyubiquitination of SDS3 resulting in negative regulation of histone deacetylase (HDAC activity in cancer cells. Furthermore, USP17 and SDS3 mutually interact with each other to block cell proliferation in HeLa cells but the mechanism for this inhibition in cell proliferation is not known. We wished to investigate whether the HABMs of USP17 were responsible for tumor suppression activity. METHODOLOGY/PRINCIPAL FINDINGS: Similarly to USP17, we have identified that SDS3 also has three consecutive HABMs and shows direct binding with hyaluronan (HA using cetylpyridinium chloride (CPC assay. Additionally, HA oligosaccharides (6-18 sugar units competitively block binding of endogenous HA polymer to HA binding proteins. Thus, administration of HA oligosaccharides antagonizes the interaction between HA and USP17 or SDS3. Interestingly, HABMs deleted USP17 showed lesser interaction with SDS3 but retain its deubiquitinating activity towards SDS3. The deletion of HABMs of USP17 could not alter its functional regulation on SDS3-associated HDAC activity. Furthermore, to explore whether HABMs in USP17 and SDS3 are responsible for the inhibition of cell proliferation, we investigated the effect of USP17 and SDS3-lacking HABMs on cell proliferation by soft agar, apoptosis, cell migration and cell proliferation assays. CONCLUSIONS: Our results have demonstrated that these HABMs in USP17 and its substrate SDS3 are mainly involved in the inhibition of anchorage-independent tumor growth.

  3. Therapeutic effects of high molecular weight hyaluronan injections for tendinopathy in a rat model.

    Science.gov (United States)

    Yoshida, Mamoru; Funasaki, Hiroki; Kubota, Makoto; Marumo, Keishi

    2015-01-01

    Tendinopathy is the most common tendon disorder. The etiology is still uncertain, and the disorder poses many therapeutic problems. In a few clinical studies, analgesic effects of high molecular weight hyaluronan (HMW HA) injections were observed, but the underlying mechanisms were not elucidated. In the present study, we analyzed the therapeutic effects of hyaluronan injections for tendinopathy in an animal model. We made the tendinopathy rat model using a rodent treadmill machine. Rats with tendinopathy were injected with HMW HA (HA group), normal saline (NS group), or nothing (control group) into the space between the patellar tendon and the fat pad bilaterally, or were injected with HMW HA into the right knees and with saline to the left knees (HA/NS group), 5 times every 4 days. To assess the pain-relieving effect of HA, the spontaneous locomotor activities at night (12 h) and weight bearing of hind paws were measured every day. Histological sections of the patellar tendon stained with hematoxylin-eosin or prepared by TdT-mediated dUTP nick end labeling were microscopically analyzed. The number of spontaneous locomotor activities in the HA group was significantly larger than those in NS or control groups, and in the HA group they recovered up to a healthy level. The percent weight distribution of the right hind paws was significantly increased along with the number of injections. On histologic examinations, the numbers of microtears, laminations, or apoptotic cells in the patellar tendons in the HA group were significantly lower than those in the NS or the control groups. The injections of HMW HA were effective for pain relief and for partial restoration of the patellar tendon in our tendinopathy rat model, and thus may become an effective therapeutic modality for the disease.

  4. High-molecular-mass hyaluronan mediates the cancer resistance of the naked mole rat.

    Science.gov (United States)

    Tian, Xiao; Azpurua, Jorge; Hine, Christopher; Vaidya, Amita; Myakishev-Rempel, Max; Ablaeva, Julia; Mao, Zhiyong; Nevo, Eviatar; Gorbunova, Vera; Seluanov, Andrei

    2013-07-18

    The naked mole rat (Heterocephalus glaber) displays exceptional longevity, with a maximum lifespan exceeding 30 years. This is the longest reported lifespan for a rodent species and is especially striking considering the small body mass of the naked mole rat. In comparison, a similarly sized house mouse has a maximum lifespan of 4 years. In addition to their longevity, naked mole rats show an unusual resistance to cancer. Multi-year observations of large naked mole-rat colonies did not detect a single incidence of cancer. Here we identify a mechanism responsible for the naked mole rat's cancer resistance. We found that naked mole-rat fibroblasts secrete extremely high-molecular-mass hyaluronan (HA), which is over five times larger than human or mouse HA. This high-molecular-mass HA accumulates abundantly in naked mole-rat tissues owing to the decreased activity of HA-degrading enzymes and a unique sequence of hyaluronan synthase 2 (HAS2). Furthermore, the naked mole-rat cells are more sensitive to HA signalling, as they have a higher affinity to HA compared with mouse or human cells. Perturbation of the signalling pathways sufficient for malignant transformation of mouse fibroblasts fails to transform naked mole-rat cells. However, once high-molecular-mass HA is removed by either knocking down HAS2 or overexpressing the HA-degrading enzyme, HYAL2, naked mole-rat cells become susceptible to malignant transformation and readily form tumours in mice. We speculate that naked mole rats have evolved a higher concentration of HA in the skin to provide skin elasticity needed for life in underground tunnels. This trait may have then been co-opted to provide cancer resistance and longevity to this species.

  5. High molecular weight hyaluronan mediates the cancer resistance of the naked mole-rat

    Science.gov (United States)

    Tian, Xiao; Azpurua, Jorge; Hine, Christopher; Vaidya, Amita; Myakishev-Rempel, Max; Ablaeva, Julia; Mao, Zhiyong; Nevo, Eviatar; Gorbunova, Vera; Seluanov, Andrei

    2013-01-01

    The naked mole-rat displays exceptional longevity, with a maximum lifespan exceeding 30 years1–3. This is the longest reported lifespan for a rodent species and is especially striking considering the small body mass of the naked mole-rat. In comparison, a similarly sized house mouse has a maximum lifespan of 4 years4,5. In addition to their longevity, naked mole-rats show an unusual resistance to cancer. Multi-year observations of large naked mole-rat colonies did not detect a single incidence of cancer2,6. Here we identify a mechanism responsible for the naked mole-rat’s cancer resistance. We found that naked mole-rat fibroblasts secrete extremely high molecular weight hyaluronan (HA), which is over five times larger than human or mouse HA. This high molecular weight HA accumulates abundantly in naked mole rat tissues due to the decreased activity of HA-degrading enzymes and a unique sequence of hyaluronan synthase 2 (HAS2). Furthermore, the naked mole-rat cells are more sensitive to HA signaling, as the naked mole rat cells have a higher affinity to HA than the mouse or human cells. Perturbation of the signaling pathways sufficient for malignant transformation of mouse fibroblasts fails to transform naked mole-rat cells. However, once high molecular weight HA is removed by either knocking down HAS2 or overexpressing the HA-degrading enzyme, Hyal2, naked mole-rat cells become susceptible to malignant transformation and readily form tumors in mice. We speculate that naked mole-rats have evolved a higher concentration of HA in the skin to provide skin elasticity needed for life in underground tunnels. This trait may have then been co-opted to provide cancer resistance and longevity to this species. PMID:23783513

  6. Increased concentration of hyaluronan in tears after soaking contact lenses in Biotrue multipurpose solution

    Directory of Open Access Journals (Sweden)

    Scheuer CA

    2016-10-01

    Full Text Available Catherine A Scheuer, Marjorie J Rah, William T Reindel Vision Care, Bausch & Lomb Incorporated, Rochester, NY, USA Purpose: This study was conducted to determine 1 the concentration of hyaluronan (HA in the tear films of contact lens (CL wearers versus non-CL wearers and 2 whether HA sorbed from Biotrue, an HA-containing multipurpose solution (MPS, onto senofilcon A lenses affects the concentration of HA in tears after 2 hours of wear.Patients and methods: Tears of habitual CL wearers and non-CL wearers were collected on Schirmer strips at baseline and after 2 hours of wear of senofilcon A CLs that had first been either rinsed with Sensitive Eyes Saline or soaked in Biotrue MPS for 14 hours. HA concentrations were measured by enzyme-linked immunosorbent assay (ELISA and adjusted for sample volumes.Results: No difference in baseline concentrations of HA in tears was found between CL wearers and non-CL wearers (P=0.07, nor between males and females (P=0.06. However, age was significantly negatively associated with HA concentration (P<0.01, and mostly, CL wear contributed to a significant association (P<0.01. Among saline-rinsed CL wearers, no change in HA concentration in tears was observed after 2 hours of wear (P=0.38. By contrast, a significant increase in HA concentration was observed in the tears from eyes that had worn CLs soaked in Biotrue MPS when compared to baseline (P=0.01 or to saline-rinsed control (P=0.03.Conclusion: 1 In this study population, no difference in baseline concentration of HA was observed between CL wearers and non-CL wearers, and 2 after 2 hours of wear of senofilcon A lenses that were soaked in Biotrue MPS, HA concentrations in the tear films of CL wearers increased. Keywords: contact lens, dry eye, hyaluronan, MPS

  7. HABP2 is a novel regulator of hyaluronan-mediated human lung cancer progression

    Directory of Open Access Journals (Sweden)

    Tamara eMirzapoiazova

    2015-07-01

    Full Text Available Background: Lung cancer is a devastating disease with limited treatment options. Many lung cancers have changes in their microenvironment including upregulation of the extracellular matrix glycosaminoglycan, hyaluronan (HA, which we have previously demonstrated can regulate the activity of the extracellular serine protease, Hyaluronan Binding Protein 2 (HABP2. This study examined the functional role of HABP2 on HA-mediated human lung cancer dynamics.Methods: Immunohistochemical analysis was performed on lung cancer patient samples using anti-HABP2 antibody. Stable control, shRNA and HABP2 overexpressing human lung adenocarcinoma cells were evaluated using immunoblot analysis, migration, extravasation and urokinase plasminogen activator (uPA activation assays with or without high molecular weight HA (HMW-HA or low molecular weight HA (LMW-HA. In human lung cancer xenograft models, primary tumor growth rates and lung metastasis were analyzed using consecutive tumor volume measurements and nestin immunoreactivity in nude mouse lungs.Results: We provide evidence that HABP2 is an important regulator of lung cancer progression. HABP2 expression was increased in several subtypes of patient non-small cell lung cancer samples. Further, HABP2 overexpression increased LMW-HA-induced uPA activation, migration and extravasation in human lung adenocarcinoma cells. In vivo, overexpression of HABP2 in human lung adenocarcinoma cells increased primary tumor growth rates in nude mice by ~2 fold and lung metastasis by ~10 fold compared to vector control cells (n=5 per condition.Conclusions: Our data suggests a possible direct effect of HABP2 on uPA activation and lung cancer progression. Our observations suggest that exploration of HABP2 in non-small cell lung carcinoma merits further study both as a diagnostic and therapeutic option.

  8. Golgi localization and dynamics of hyaluronan binding protein 1 (HABP1/p32/C1QBP) during the cell cycle

    Institute of Scientific and Technical Information of China (English)

    Aniruddha SENGUPTA; Bhaswati BANERJEE; Rakesh K. TYAGI; Kasturi DATTA

    2005-01-01

    Hyaluronan binding protein 1 (HABP1) is a negatively charged multifunctional mammalian protein with a unique structural fold. Despite the fact that HABP1 possesses mitochondrial localization signal, it has also been localized to other cellular compartments. Using indirect immunofluorescence, we examined the sub-cellular localization of HABP1 and its dynamics during mitosis. We wanted to determine whether it distributes in any distinctive manner after mitotic nuclear envelope disassembly or is dispersed randomly throughout the cell. Our results reveal the golgi localization of HABP1 and demonstrate its complete dispersion throughout the cell during mitosis. This distinctive distribution pattern of HABP1 during mitosis resembles its ligand hyaluronan, suggesting that in concert with each other the two molecules play critical roles in this dynamic process.

  9. Inhibition of Ovarian Cancer Chemoresistance and Metastasis with Antagonists of Hyaluronan-CD44-CD147 Interactions

    Science.gov (United States)

    2015-09-01

    and emmprin regulate lactate efflux and membrane localization of monocarboxylate transporters in human breast carcinoma cells. Cancer Res. 69:1293...1 AWARD NUMBER: W81XWH-12-1-0268 TITLE: Inhibition of Ovarian Cancer Chemoresistance and Metastasis with Antagonists of Hyaluronan-CD44-CD147...3. DATES COVERED 1 July, 2012 – 30 June, 2015 4. TITLE AND SUBTITLE Inhibition of Ovarian Cancer Chemoresistance and Metastasis with Antagonists of

  10. Sperm DNA Fragmentation Index and Hyaluronan Binding Ability in Men from Infertile Couples and Men with Testicular Germ Cell Tumor

    OpenAIRE

    Katarzyna Marchlewska; Eliza Filipiak; Renata Walczak-Jedrzejowska; Elzbieta Oszukowska; Slawomir Sobkiewicz; Malgorzata Wojt; Jacek Chmiel; Krzysztof Kula; Jolanta Slowikowska-Hilczer

    2016-01-01

    Objective. To investigate sperm DNA fragmentation and sperm functional maturity in men from infertile couples (IC) and men with testicular germ cell tumor (TGCT). Materials and Methods. Semen samples were collected from 312 IC men and 23 men with TGCT before unilateral orchiectomy and oncological treatment. The sperm chromatin dispersion test was performed to determine DNA fragmentation index (DFI) and the ability of sperm to bind with hyaluronan (HA) was assessed. Results. In comparison with...

  11. Cytocompatible in situ forming chitosan/hyaluronan hydrogels via a metal-free click chemistry for soft tissue engineering.

    Science.gov (United States)

    Fan, Ming; Ma, Ye; Mao, Jiahui; Zhang, Ziwei; Tan, Huaping

    2015-07-01

    Injectable hydrogels are important cell scaffolding materials for tissue engineering and regenerative medicine. Here, we report a new class of biocompatible and biodegradable polysaccharide hydrogels derived from chitosan and hyaluronan via a metal-free click chemistry, without the addition of copper catalyst. For the metal-free click reaction, chitosan and hyaluronan were modified with oxanorbornadiene (OB) and 11-azido-3,6,9-trioxaundecan-1-amine (AA), respectively. The gelation is attributed to the triazole ring formation between OB and azido groups of polysaccharide derivatives. The molecular structures were verified by FT-IR spectroscopy and elemental analysis, giving substitution degrees of 58% and 47% for chitosan-OB and hyaluronan-AA, respectively. The in vitro gelation, morphologies, equilibrium swelling, compressive modulus and degradation of the composite hydrogels were examined. The potential of the metal-free hydrogel as a cell scaffold was demonstrated by encapsulation of human adipose-derived stem cells (ASCs) within the gel matrix in vitro. Cell culture showed that this metal-free hydrogel could support survival and proliferation of ASCs. A preliminary in vivo study demonstrated the usefulness of the hydrogel as an injectable scaffold for adipose tissue engineering. These characteristics provide a potential opportunity to use the metal-free click chemistry in preparation of biocompatible hydrogels for soft tissue engineering applications. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  12. Conformational Analysis of the Streptococcus pneumoniae Hyaluronate Lyase and Characterization of Its Hyaluronan-specific Carbohydrate-binding Module*

    Science.gov (United States)

    Suits, Michael D. L.; Pluvinage, Benjamin; Law, Adrienne; Liu, Yan; Palma, Angelina S.; Chai, Wengang; Feizi, Ten; Boraston, Alisdair B.

    2014-01-01

    For a subset of pathogenic microorganisms, including Streptococcus pneumoniae, the recognition and degradation of host hyaluronan contributes to bacterial spreading through the extracellular matrix and enhancing access to host cell surfaces. The hyaluronate lyase (Hyl) presented on the surface of S. pneumoniae performs this role. Using glycan microarray screening, affinity electrophoresis, and isothermal titration calorimetry we show that the N-terminal module of Hyl is a hyaluronan-specific carbohydrate-binding module (CBM) and the founding member of CBM family 70. The 1.2 Å resolution x-ray crystal structure of CBM70 revealed it to have a β-sandwich fold, similar to other CBMs. The electrostatic properties of the binding site, which was identified by site-directed mutagenesis, are distinct from other CBMs and complementary to its acidic ligand, hyaluronan. Dynamic light scattering and solution small angle x-ray scattering revealed the full-length Hyl protein to exist as a monomer/dimer mixture in solution. Through a detailed analysis of the small angle x-ray scattering data, we report the pseudoatomic solution structures of the monomer and dimer forms of the full-length multimodular Hyl. PMID:25100731

  13. Hyaluronan and Fibrin Biomaterial as Scaffolds for Neuronal Differentiation of Adult Stem Cells Derived from Adipose Tissue and Skin

    Directory of Open Access Journals (Sweden)

    Chiara Gardin

    2011-10-01

    Full Text Available Recently, we have described a simple protocol to obtain an enriched culture of adult stem cells organized in neurospheres from two post-natal tissues: skin and adipose tissue. Due to their possible application in neuronal tissue regeneration, here we tested two kinds of scaffold well known in tissue engineering application: hyaluronan based membranes and fibrin-glue meshes. Neurospheres from skin and adipose tissue were seeded onto two scaffold types: hyaluronan based membrane and fibrin-glue meshes. Neurospheres were then induced to acquire a glial and neuronal-like phenotype. Gene expression, morphological feature and chromosomal imbalance (kariotype were analyzed and compared. Adipose and skin derived neurospheres are able to grow well and to differentiate into glial/neuron cells without any chromosomal imbalance in both scaffolds. Adult cells are able to express typical cell surface markers such as S100; GFAP; nestin; βIII tubulin; CNPase. In summary, we have demonstrated that neurospheres isolated from skin and adipose tissues are able to differentiate in glial/neuron-like cells, without any chromosomal imbalance in two scaffold types, useful for tissue engineering application: hyaluronan based membrane and fibrin-glue meshes.

  14. Overexpression of Hyaluronan-binding Protein 1 (HABP1/p32/gC1qR) in HepG2 Cells Leads to Increased Hyaluronan Synthesis and Cell Proliferation by Up-regulation of Cyclin D1 in AKT-dependent Pathway*

    Science.gov (United States)

    Kaul, Rachna; Saha, Paramita; Saradhi, Mallampati; Prasad, Ramachandra L. A.; Chatterjee, Soumya; Ghosh, Ilora; Tyagi, Rakesh K.; Datta, Kasturi

    2012-01-01

    Overexpression of the mature form of hyaluronan-binding protein 1 (HABP1/gC1qR/p32), a ubiquitous multifunctional protein involved in cellular signaling, in normal murine fibroblast cells leads to enhanced generation of reactive oxygen species (ROS), mitochondrial dysfunction, and ultimately apoptosis with the release of cytochrome c. In the present study, human liver cancer cell line HepG2, having high intracellular antioxidant levels was chosen for stable overexpression of HABP1. The stable transformant of HepG2, overexpressing HABP1 does not lead to ROS generation, cellular stress, and apoptosis, rather it induced enhanced cell growth and proliferation over longer periods. Phenotypic changes in the stable transformant were associated with the increased “HA pool,” formation of the “HA cable” structure, up-regulation of HA synthase-2, and CD44, a receptor for HA. Enhanced cell survival was further supported by activation of MAP kinase and AKT-mediated cell survival pathways, which leads to an increase in CYCLIN D1 promoter activity. Compared with its parent counterpart HepG2, the stable transformant showed enhanced tumorigenicity as evident by its sustained growth in low serum conditions, formation of the HA cable structure, increased anchorage-independent growth, and cell-cell adhesion. This study suggests that overexpression of HABP1 in HepG2 cells leads to enhanced cell survival and tumorigenicity by activating HA-mediated cell survival pathways. PMID:22451658

  15. Green synthesis, characterization, and anticancer activity of hyaluronan/zinc oxide nanocomposites

    Directory of Open Access Journals (Sweden)

    Namvar F

    2016-07-01

    Full Text Available Farideh Namvar,1,2 Susan Azizi,3 Heshu Sulaiman Rahman,4–6 Rosfarizan Mohamad,1,3 Abdullah Rasedee,4 Mozhgan Soltani,2 Raha Abdul Rahim71Institute of Tropical Forestry and Forest Products (INTROP, Universiti Putra Malaysia, UPM Serdang, Selangor, Malaysia; 2Research Center for Animal Development Applied Biology, Mashhad Branch, Islamic Azad University, Mashhad, Iran; 3Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, 4Department of Veterinary Laboratory Diagnosis, Faculty of Veterinary Medicine, Universiti Putra Malaysia, UPM Serdang, Selangor, Malaysia; 5Department of Clinic and Internal Medicine, College of Veterinary Medicine, University of Sulaimani, 6Department of Laboratory Medical Sciences, Komar University of Science and Technology, Sulaimani City, Kurdistan Region, Northern Iraq; 7Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, UPM Serdang, Selangor, Malaysia Abstract: The study describes an in situ green biosynthesis of zinc oxide nanocomposite using the seaweed Sargassum muticum water extract and hyaluronan biopolymer. The morphology and optical properties of the hyaluronan/zinc oxide (HA/ZnO nanocomposite were determined by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and ultraviolet–vis analysis. Electron microscopy and X-ray diffraction analysis showed that the zinc oxide nanoparticles were polydispersed with a mean size of 10.2±1.5 nm. The nanoparticles were mostly hexagonal in crystalline form. The HA/ZnO nanocomposite showed the absorption properties in the ultraviolet zone that is ascribed to the band gap of zinc oxide nanocomposite. In the cytotoxicity study, cancer cells, pancreatic adenocarcinoma (PANC-1, ovarian adenocarcinoma (CaOV-3, colonic adenocarcinoma (COLO205, and acute promyelocytic leukemia (HL-60 cells

  16. Improvement and enhancement of antibladder carcinoma cell effects of heteronemin by the nanosized hyaluronan aggregation

    Directory of Open Access Journals (Sweden)

    Huang HH

    2016-03-01

    Full Text Available Han Hsiang Huang,1 Shyh Ming Kuo,2 Yi-Jhen Wu,2 Jui-Hsin Su3 1Department of Veterinary Medicine, National Chiayi University, Chiayi City, 2Department of Biomedical Engineering, I-Shou University, Kaohsiung City, 3National Museum of Marine Biology and Aquarium, Pingtung, Taiwan Abstract: The effects against tumors exerted by marine active compounds have been highlighted and investigated. Polymeric nanoparticles made from biodegradable and biocompatible molecules such as hyaluronan (HA and chitosan (CHI are able to aggregate the compounds to enhance their activities against tumor cells and reduce the toxicity on normal cells. Here, we extensively examined the antitumor activities and the mechanisms of HA/CHI nanoparticles-aggregated heteronemin (HET extracted from the sponge Hippospongia sp. The half-maximal inhibitory concentration (IC50 of pure HET toward T24 bladder carcinoma cells is ~0.28 µg/mL. Pure HET from 0.2 to 0.8 µg/mL and HA nanoparticles-aggregated HET at 0.1 and 0.2 µg/mL significantly reduced T24 cell viability. Compared to pure HET, HA nanoparticles/HET aggregates showed much weaker viability-inhibitory effects on L929 normal fibroblasts. HET dose-dependently suppressed cancer cell migration as HA/CHI nanoparticles-aggregated HET displayed stronger migration-inhibitory effects than pure HET. Flow cytometric analysis showed that pure HET increased early/total apoptosis and JC-1 monomer fluorescence, while HA/CHI nanoparticles-aggregated HET induced higher apoptosis and JC-1 monomer rates than pure HET, suggesting that aggregation of HA nanoparticles offers HET stronger apoptosis-inducing capacity through mitochondrial depolarization. Western blot analysis showed that HA nanoparticles-aggregated HET further increased mitochondrial-associated, caspase-dependent and caspase-independent, as well as endoplasmic reticulum stress-related factors in comparison with pure HET. These data indicated that pure HET possesses cytotoxic

  17. Green synthesis, characterization, and anticancer activity of hyaluronan/zinc oxide nanocomposite.

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    Namvar, Farideh; Azizi, Susan; Rahman, Heshu Sulaiman; Mohamad, Rosfarizan; Rasedee, Abdullah; Soltani, Mozhgan; Rahim, Raha Abdul

    2016-01-01

    The study describes an in situ green biosynthesis of zinc oxide nanocomposite using the seaweed Sargassum muticum water extract and hyaluronan biopolymer. The morphology and optical properties of the hyaluronan/zinc oxide (HA/ZnO) nanocomposite were determined by Fourier transform infrared spectroscopy, X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, and ultraviolet-vis analysis. Electron microscopy and X-ray diffraction analysis showed that the zinc oxide nanoparticles were polydispersed with a mean size of 10.2±1.5 nm. The nanoparticles were mostly hexagonal in crystalline form. The HA/ZnO nanocomposite showed the absorption properties in the ultraviolet zone that is ascribed to the band gap of zinc oxide nanocomposite. In the cytotoxicity study, cancer cells, pancreatic adenocarcinoma (PANC-1), ovarian adenocarcinoma (CaOV-3), colonic adenocarcinoma (COLO205), and acute promyelocytic leukemia (HL-60) cells were treated with HA/ZnO nanocomposite. At 72 hours of treatment, the half maximal inhibitory concentration (IC50) value via the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was 10.8±0.3 μg/mL, 15.4±1.2 μg/mL, 12.1±0.9 μg/mL, and 6.25±0.5 μg/mL for the PANC-1, CaOV-3, COLO-205, and HL-60 cells, respectively, showing that the composite is most toxic to the HL-60 cells. On the other hand, HA/ZnO nanocomposite treatment for 72 hours did not cause toxicity to the normal human lung fibroblast (MRC-5) cell line. Using fluorescent dyes and flow cytometry analysis, HA/ZnO nanocomposite caused G2/M cell cycle arrest and stimulated apoptosis-related increase in caspase-3 and -7 activities of the HL-60 cells. Thus, the study shows that the HA/ZnO nanocomposite produced through green synthesis has great potential to be developed into an efficacious therapeutic agent for cancers.

  18. High molecular weight hyaluronan for treatment of chronic shoulder pain associated with glenohumeral arthritis

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    Weil AJ

    2011-07-01

    Full Text Available Arnold J WeilNon-Surgical Orthopedics PC, Marietta, GA, USABackground: There is insufficient evidence to determine whether intra-articular injections may be effective for treatment of glenohumeral osteoarthritis. Euflexxa® (high molecular weight hyaluronate, a bioengineered high molecular weight hyaluronan, has been shown to be a safe and effective treatment for patients with knee osteoarthritis. There is also support for the use of hyaluronate injection for the treatment of chronic shoulder pain associated with osteoarthritis or rotator cuff damage. This small-scale exploratory study was conducted to evaluate the safety and efficacy of high molecular weight hyaluronate for the treatment of chronic shoulder pain associated with osteoarthritis.Methods: Subjects with glenohumeral osteoarthritis and chronic pain (n = 27 received one injection per week for 3 weeks of high molecular weight hyaluronate and were assessed for changes in pain (100 mm visual analog scale [VAS], range of motion, and the subject’s and physician’s global assessment over 26 weeks. Subjects were also assessed for pain, stiffness, and physical functioning using the Western Ontario and McMaster Universities Arthritis Index (WOMAC. Finally, responses were evaluated using modified Outcome Measures in Rheumatoid Arthritis Clinical Trials (OMERACT-Osteoarthritis Research Society International (OARSI Proposition D criteria. Safety was assessed by recording adverse events.Results: High molecular weight hyaluronate significantly improved pain (VAS, WOMAC, range of motion, stiffness, and physical functioning scores; 77.8% of subjects were rated as having an OMERACT-OARSI Proposition D high response. There were no serious adverse events, and none were considered to be related to treatment.Conclusion: Treatment with high molecular weight hyaluronate improves pain, stiffness, and range of motion, and may have an acceptable safety and tolerability profile. A randomized, double

  19. Lymphatic Regulation of Cellular Trafficking

    Science.gov (United States)

    Jackson, David G.

    2016-01-01

    Lymphatic vessels play vital roles in immune surveillance and immune regulation by conveying antigen loaded dendritic cells, memory T cells, macrophages and neutrophils from the peripheral tissues to draining lymph nodes where they initiate as well as modify immune responses. Until relatively recently however, there was little understanding of how entry and migration through lymphatic vessels is organized or the specific molecular mechanisms that might be involved. Within the last decade, the situation has been transformed by an explosion of knowledge generated largely through the application of microscopic imaging, transgenic animals, specific markers and function blocking mAbs that is beginning to provide a rational conceptual framework. This article provides a critical review of the recent literature, highlighting seminal discoveries that have revealed the fascinating ultrastructure of leucocyte entry sites in lymphatic vessels, as well as generating controversies over the involvement of integrin adhesion, chemotactic and haptotactic mechanisms in DC entry under normal and inflamed conditions. It also discusses the major changes in lymphatic architecture that occur during inflammation and the different modes of leucocyte entry and trafficking within inflamed lymphatic vessels, as well as presenting a timely update on the likely role of hyaluronan and the major lymphatic endothelial hyaluronan receptor LYVE-1 in leucocyte transit.

  20. Engineering the periodontal ligament in hyaluronan-gelatin-type I collagen constructs: upregulation of apoptosis and alterations in gene expression by cyclic compressive strain.

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    Saminathan, Aarthi; Sriram, Gopu; Vinoth, Jayasaleen Kumar; Cao, Tong; Meikle, Murray C

    2015-02-01

    To engineer constructs of the periodontal ligament (PDL), human PDL cells were incorporated into a matrix of hyaluronan, gelatin, and type I collagen (COLI) in sample holders (13×1 mm) of six-well Biopress culture plates. The loading dynamics of the PDL were mimicked by applying a cyclic compressive strain of 33.4 kPa (340.6 gm/cm(2)) to the constructs for 1.0 s every 60 s, for 6, 12, and 24 h in a Flexercell FX-4000C Strain Unit. Compression significantly increased the number of nonviable cells and increased the expression of several apoptosis-related genes, including initiator and executioner caspases. Of the 15 extracellular matrix genes screened, most were upregulated at some point after 6-12 h deformation, but all were downregulated at 24 h, except for MMPs1-3 and CTGF. In culture supernatants, matrix metalloproteinase-1 (MMP-1) and tissue inhibitor of metalloproteinases-1 (TIMP-1) protein levels were upregulated at 24 h; receptor activator of nuclear kappa factor B (RANKL), osteoprotegerin (OPG) and fibroblast growth factor-2 (FGF-2) were unchanged; and connective tissue growth factor (CTGF) not detected. The low modulus of elasticity of the constructs was a disadvantage-future mechanobiology studies and tissue engineering applications will require constructs with much higher stiffness. Since the major structural protein of the PDL is COLI, a more rational approach would be to permeabilize preformed COLI scaffolds with PDL-populated matrices.

  1. Synthesis and characterization of a Hyaluronan-polyethylene copolymer for biomedical applications.

    Science.gov (United States)

    Oldinski, Rachael A; Cranson, Cody N; James, Susan P

    2010-08-01

    Hyaluronan (HA)-based biomaterials are of interest for bone and cartilage tissue engineering because HA plays an important role in orthopedic tissue development, function, and repair. The goal of this project was to develop a biomaterial that incorporated the constituents of both a hydrogel and a hydrophobic polymer for biomedical applications. A series of amphiphilic graft copolymers consisting of HA, a glycosaminoglycan, and high-density polyethylene (HDPE), that is, HA-co-HDPE, were fabricated. The chemical characteristics, physical and viscoelastic properties, and cytocompatibility of novel HA-co-HDPE materials were characterized via Fourier Transform infrared (FTIR) spectroscopy, solid state nuclear magnetic resonance (ssNMR) spectroscopy, differential scanning calorimetry (DSC), dynamic shear testing, and an in vitro human osteoblast cell study. The esterification reaction between HA and functionalized HDPE resulted in semicrystalline, insoluble powder. The dynamic shear properties of HA-co-HDPE concentrated solutions were more like natural proteoglycans than the HA control. HA-co-HDPE was successfully compression molded into disks that swelled upon hydration. Osteoblasts were viable and expressed the osteoblast phenotype after 7 days of culture on HA-co-HDPE materials. These HA-co-HDPE materials may have several biomaterial applications in saline suspension or molded form, including orthopedic tissue repair.

  2. Two fluoroquinolones and their combinations with hyaluronan: comparison of effects on canine chondrocyte culture.

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    Siengdee, P; Euppayo, T; Buddhachat, K; Chomdej, S; Nganvongpanit, K

    2016-10-01

    Fluoroquinolones (FQs) are frequently used for septic arthritis. Increased antibacterial activity has been associated with mammalian cell cytotoxicity that may increase the risk of developing osteoarthritis. This study compared the direct effects of two different FQs, enrofloxacin (Enro) and marbofloxacin (Mar), on normal primary canine chondrocytes and inflammatory-stimulated chondrocytes, in addition to their administration in combination with hyaluronan (HA). Cell viability, cell apoptosis, s-GAG production, and expression patterns of inflammatory, extracellular matrix (ECM) component and protease genes were measured. Enro co-culturing with HA could modify s-GAG synthesis compared with the negative control group. Co-treatment with both FQs and HA significantly decreased cell viability and induced more total apoptotic cell death compared with the negative control and pre-IL-1β-stimulated group. Enro regulated IL-1β-stimulated cells to overexpress IL-1β, TNF, and MMP3, whereas Mar induced upregulation of PTGS2 and NFKB1 and enhanced the expression of ECM component genes HAS1, COL2A1, and ACAN as well as TIMP1 and MMP9. Simultaneous use of HA with Enro can effectively reduce the expression of IL-1β, TNF, and MMP3 in pre-IL-1β-stimulated chondrocytes. These results suggest the beneficial effects of HA in reducing the adverse effects of Enro treatment at the transcriptional level. © 2016 John Wiley & Sons Ltd.

  3. Computational Study of Nanosized Drug Delivery from Cyclodextrins, Crown Ethers and Hyaluronan in Pharmaceutical Formulations.

    Science.gov (United States)

    Torrens, Francisco; Castellano, Gloria

    2015-01-01

    The problem in this work is the computational characterization of cyclodextrins, crown ethers and hyaluronan (HA) as hosts of inclusion complexes for nanosized drug delivery vehicles in pharmaceutical formulations. The difficulty is addressed through a computational study of some thermodynamic, geometric and topological properties of the hosts. The calculated properties of oligosaccharides of D-glucopyranoses allow these to act as co-solvents of polyanions in water. In crown ethers, the central channel is computed. Mucoadhesive polymer HA in formulations releases drugs in mucosas. Geometric, topological and fractal analyses are carried out with code TOPO. Reference calculations are performed with code GEPOL. From HA to HA·3Ca and hydrate, the hydrophilic solvent-accessible surface varies with the count of H-bonds. The fractal dimension rises. The dimension of external atoms rises resulting 1.725 for HA. It rises going to HA·3Ca and hydrate. Nonburied minus molecular dimension rises and decays. Hydrate globularity is lower than O(water), Ca(2+) and O(HA). Ca(2+) rugosity is smaller than for hydrate, O(HA) and O(water). Ca(2+) and O(water) accessibilities are greater than hydrate. Conclusions are drawn on: (1) the relative stability of linear/cyclic and shorter/larger polymers; (2) the atomic analysis of properties allows determining the atoms with maximum reactivity.

  4. Anticancer Effects of Sinulariolide-Conjugated Hyaluronan Nanoparticles on Lung Adenocarcinoma Cells

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    Kuan Yin Hsiao

    2016-03-01

    Full Text Available Lung cancer is one of the most clinically challenging malignant diseases worldwide. Sinulariolide (SNL, extracted from the farmed coral species Sinularia flexibilis, has been used for suppressing malignant cells. For developing anticancer therapeutic agents, we aimed to find an alternative for non-small cell lung cancer treatment by using SNL as the target drug. We investigated the SNL bioactivity on A549 lung cancer cells by conjugating SNL with hyaluronan nanoparticles to form HA/SNL aggregates by using a high-voltage electrostatic field system. SNL was toxic on A549 cells with an IC50 of 75 µg/mL. The anticancer effects of HA/SNL aggregates were assessed through cell viability assay, apoptosis assays, cell cycle analyses, and western blotting. The size of HA/SNL aggregates was approximately 33–77 nm in diameter with a thin continuous layer after aggregating numerous HA nanoparticles. Flow cytometric analysis revealed that the HA/SNL aggregate-induced apoptosis was more effective at a lower SNL dose of 25 µg/mL than pure SNL. Western blotting indicated that caspases-3, -8, and -9 and Bcl-xL and Bax played crucial roles in the apoptotic signal transduction pathway. In summary, HA/SNL aggregates exerted stronger anticancer effects on A549 cells than did pure SNL via mitochondria-related pathways.

  5. Mechanical properties of tyramine substituted-hyaluronan enriched fascia extracellular matrix.

    Science.gov (United States)

    Chin, Likang; Calabro, Anthony; Walker, Esteban; Derwin, Kathleen A

    2012-03-01

    Naturally occurring biomaterial scaffolds derived from extracellular matrix (ECM) have been the topic of recent investigation in the context of rotator cuff tendon repair. We previously reported a method to treat fascia ECM with high molecular weight tyramine substituted-hyaluronan (TS-HA) for use as a tendon augmentation scaffold. The presence of crosslinked TS-HA in fascia was associated with an increased macrophage and giant cell response compared to water-treated controls after implantation in a rat abdominal wall model. The objective of this study was to determine the extent to which TS-HA treatment was associated with mechanical property changes of fascia after implantation in the rat model. Fascia samples in all groups demonstrated time-dependent decreases in mechanical properties. TS-HA-treated fascia with crosslinking exhibited a lower toe modulus, a trend toward lower toe stiffness, and a higher transition strain than water-treated controls not only after implantation, but also at time zero. TS-HA treatment, with or without crosslinking, had no significant effect on time-zero or post-implantation load relaxation ratio, load relaxation rate, linear-region stiffness, or linear-region modulus. Our findings demonstrated that the particular TS-HA treatment employed in this study decreased the low-load elastic mechanical properties of fascia ECM, in keeping with the heightened macrophage and giant cell host response seen previously. This work provides a starting point and guidance for investigating alternative HA treatment strategies.

  6. BMP-2 induces versican and hyaluronan that contribute to post-EMT AV cushion cell migration.

    Science.gov (United States)

    Inai, Kei; Burnside, Jessica L; Hoffman, Stanley; Toole, Bryan P; Sugi, Yukiko

    2013-01-01

    Distal outgrowth and maturation of mesenchymalized endocardial cushions are critical morphogenetic events during post-EMT atrioventricular (AV) valvuloseptal morphogenesis. We explored the role of BMP-2 in the regulation of valvulogenic extracellular matrix (ECM) components, versican and hyaluronan (HA), and cell migration during post-EMT AV cushion distal outgrowth/expansion. We observed intense staining of versican and HA in AV cushion mesenchyme from the early cushion expansion stage, Hamburger and Hamilton (HH) stage-17 to the cushion maturation stage, HH stage-29 in the chick. Based on this expression pattern we examined the role of BMP-2 in regulating versican and HA using 3D AV cushion mesenchymal cell (CMC) aggregate cultures on hydrated collagen gels. BMP-2 induced versican expression and HA deposition as well as mRNA expression of versican and Has2 by CMCs in a dose dependent manner. Noggin, an antagonist of BMP, abolished BMP-2-induced versican and HA as well as mRNA expression of versican and Has2. We further examined whether BMP-2-promoted cell migration was associated with expression of versican and HA. BMP-2- promoted cell migration was significantly impaired by treatments with versican siRNA and HA oligomer. In conclusion, we provide evidence that BMP-2 induces expression of versican and HA by AV CMCs and that these ECM components contribute to BMP-2-induced CMC migration, indicating critical roles for BMP-2 in distal outgrowth/expansion of mesenchymalized AV cushions.

  7. BMP-2 induces versican and hyaluronan that contribute to post-EMT AV cushion cell migration.

    Directory of Open Access Journals (Sweden)

    Kei Inai

    Full Text Available Distal outgrowth and maturation of mesenchymalized endocardial cushions are critical morphogenetic events during post-EMT atrioventricular (AV valvuloseptal morphogenesis. We explored the role of BMP-2 in the regulation of valvulogenic extracellular matrix (ECM components, versican and hyaluronan (HA, and cell migration during post-EMT AV cushion distal outgrowth/expansion. We observed intense staining of versican and HA in AV cushion mesenchyme from the early cushion expansion stage, Hamburger and Hamilton (HH stage-17 to the cushion maturation stage, HH stage-29 in the chick. Based on this expression pattern we examined the role of BMP-2 in regulating versican and HA using 3D AV cushion mesenchymal cell (CMC aggregate cultures on hydrated collagen gels. BMP-2 induced versican expression and HA deposition as well as mRNA expression of versican and Has2 by CMCs in a dose dependent manner. Noggin, an antagonist of BMP, abolished BMP-2-induced versican and HA as well as mRNA expression of versican and Has2. We further examined whether BMP-2-promoted cell migration was associated with expression of versican and HA. BMP-2- promoted cell migration was significantly impaired by treatments with versican siRNA and HA oligomer. In conclusion, we provide evidence that BMP-2 induces expression of versican and HA by AV CMCs and that these ECM components contribute to BMP-2-induced CMC migration, indicating critical roles for BMP-2 in distal outgrowth/expansion of mesenchymalized AV cushions.

  8. Circular Halbach array for fast magnetic separation of hyaluronan-expressing tissue progenitors.

    Science.gov (United States)

    Joshi, Powrnima; Williams, P Stephen; Moore, Lee R; Caralla, Tonya; Boehm, Cynthia; Muschler, George; Zborowski, Maciej

    2015-10-06

    Connective tissue progenitors (CTPs) are a promising therapeutic agent for bone repair. Hyaluronan, a high molecular mass glycosaminoglycan, has been shown by us to be a suitable biomarker for magnetic separation of CTPs from bone marrow aspirates in a canine model. For the therapy to be applicable in humans, the magnetic separation process requires scale-up without compromising the viability of the cells. The scaled-up device presented here utilizes a circular Halbach array of diametrically magnetized, cylindrical permanent magnets. This allows precise control of the magnetic field gradient driving the separation, with theoretical analysis favoring a hexapole field. The separation vessel has the external diameter of a 50 mL conical centrifuge tube and has an internal rod that excludes cells from around the central axis. The magnet and separation vessel (collectively dubbed the hexapole magnet separator or HMS) was tested on four human and four canine bone marrow aspirates. Each CTP-enriched cell product was tested using cell culture bioassays as surrogates for in vivo engraftment quality. The magnetically enriched cell fractions showed statistically significant, superior performance compared to the unenriched and depleted cell fractions for all parameters tested, including CTP prevalence (CTPs per 10(6) nucleated cells), proliferation by colony forming unit (CFU) counts, and differentiation by staining for the presence of osteogenic and chondrogenic cells. The simplicity and speed of the HMS operation could allow both CTP isolation and engraftment during a single surgical procedure, minimizing trauma to patients and lowering cost to health care providers.

  9. Hyaluronan/Tween 80-assisted synthesis of silver nanoparticles for biological application

    Science.gov (United States)

    Li, Hui-Jun; Zhang, An-Qi; Sui, Li; Qian, Dong-Jin; Chen, Meng

    2015-02-01

    Water-soluble and well-stabilized silver nanoparticles (NPs) of small size have been synthesized using hyaluronan (HA) and Tween 80 as reducing and stabilizing agents. The effect of reaction conditions on the formation process of silver NPs was studied, and an aggregative growth mechanism of the silver NPs dominated in HA/Tween 80 system at pH 12 has been proposed. The obtained Ag NPs were characterized by UV-Vis spectroscopy, transmission electron microscopy, X-ray powder diffraction, and X-ray photoelectron spectroscopy. Moreover, the stability of the HA-Tween 80-silver NPs in normal saline was also studied, and a flexible blend membrane containing chitosan, gelatin, and the HA-Tween 80-silver NPs was prepared for further biological applications. Due to the high specific surface area and improved stability of silver NPs, the chitosan-gelatin-silver membrane has shown high antibacterial activity for strains of Escherichia coli. The cell viability tests indicate that the polymer membrane is non-cytotoxic to HepG2 cells, which might be attributed to its good biocompatibility.

  10. Influence of hyaluronan on endometrial receptivity and embryo attachment in sheep.

    Science.gov (United States)

    Marei, Waleed F A; Wathes, D Claire; Raheem, Kabir A; Mohey-Elsaeed, Omnia; Ghafari, Fataneh; Fouladi-Nashta, Ali A

    2016-10-11

    An increasing number of reports suggests a role of hyaluronan (HA) in female reproduction and interest in its application in assisted reproduction is rising. However, there are contrasting data about the effectiveness of adding HA to the embryo-transfer medium on improving pregnancy rates. Using sheep as an experimental model, the studies reported here analysed the impact of HA infusion into the uterus on embryo attachment to uterine luminal epithelium (LE) and expression of selected markers of uterine receptivity. On Day 14 after natural mating (pre-attachment), uterine horns were infused with either (n=4 each): PBS (control), HA (1mg mL-1), HA+hyaluronidase 2 (Hyal2; 300IU mL-1) or 4-methyl-umbelliferone (HA-synthesis inhibitor; 4MU, 1mM). HA immunostaining on uterine sections collected on Day 17 was negative in the 4MU group and weak in the HA+Hyal2 group. In contrast to 4MU, which resulted in 100% attachment, HA infusion blocked embryo attachment in all treated animals. This was accompanied by the disappearance of mucin 1 and increased expression of osteopontin and CD44v6 in the LE of uteri with attached embryos. In conclusion, the presence of HA at the embryo-maternal interface during embryo implantation resulted in reduced endometrial receptivity and inhibited the interaction of trophoblasts with the LE, whereas clearance of HA favoured embryo attachment.

  11. Successful transplantation of human hepatic stem cells with restricted localization to liver using hyaluronan grafts.

    Science.gov (United States)

    Turner, Rachael A; Wauthier, Eliane; Lozoya, Oswaldo; McClelland, Randall; Bowsher, James E; Barbier, Claire; Prestwich, Glenn; Hsu, Edward; Gerber, David A; Reid, Lola M

    2013-02-01

    Cell therapies are potential alternatives to organ transplantation for liver failure or dysfunction but are compromised by inefficient engraftment, cell dispersal to ectopic sites, and emboli formation. Grafting strategies have been devised for transplantation of human hepatic stem cells (hHpSCs) embedded into a mix of soluble signals and extracellular matrix biomaterials (hyaluronans, type III collagen, laminin) found in stem cell niches. The hHpSCs maintain a stable stem cell phenotype under the graft conditions. The grafts were transplanted into the livers of immunocompromised murine hosts with and without carbon tetrachloride treatment to assess the effects of quiescent versus injured liver conditions. Grafted cells remained localized to the livers, resulting in a larger bolus of engrafted cells in the host livers under quiescent conditions and with potential for more rapid expansion under injured liver conditions. By contrast, transplantation by direct injection or via a vascular route resulted in inefficient engraftment and cell dispersal to ectopic sites. Transplantation by grafting is proposed as a preferred strategy for cell therapies for solid organs such as the liver.

  12. Hyaluronan synthesis is necessary for autoreactive T-cell trafficking, activation, and Th1 polarization.

    Science.gov (United States)

    Kuipers, Hedwich F; Rieck, Mary; Gurevich, Irina; Nagy, Nadine; Butte, Manish J; Negrin, Robert S; Wight, Thomas N; Steinman, Lawrence; Bollyky, Paul L

    2016-02-02

    The extracellular matrix polysaccharide hyaluronan (HA) accumulates at sites of autoimmune inflammation, including white matter lesions in multiple sclerosis (MS), but its functional importance in pathogenesis is unclear. We have evaluated the impact of 4-methylumbelliferone (4-MU), an oral inhibitor of HA synthesis, on disease progression in the experimental autoimmune encephalomyelitis (EAE) mouse model of MS. Treatment with 4-MU decreases the incidence of EAE, delays its onset, and reduces the severity of established disease. 4-MU inhibits the activation of autoreactive T cells and prevents their polarization toward a Th1 phenotype. Instead, 4-MU promotes polarization toward a Th2 phenotpye and induction of Foxp3(+) regulatory T cells. Further, 4-MU hastens trafficking of T cells through secondary lymphoid organs, impairs the infiltration of T cells into the CNS parenchyma, and limits astrogliosis. Together, these data suggest that HA synthesis is necessary for disease progression in EAE and that treatment with 4-MU may be a potential therapeutic strategy in CNS autoimmunity. Considering that 4-MU is already a therapeutic, called hymecromone, that is approved to treat biliary spasm in humans, we propose that it could be repurposed to treat MS.

  13. Hyaluronan-Phosphatidylethanolamine Polymers Form Pericellular Coats on Keratinocytes and Promote Basal Keratinocyte Proliferation

    Directory of Open Access Journals (Sweden)

    Caitlin J. Symonette

    2014-01-01

    Full Text Available Aged keratinocytes have diminished proliferative capacity and hyaluronan (HA cell coats, which are losses that contribute to atrophic skin characterized by reduced barrier and repair functions. We formulated HA-phospholipid (phosphatidylethanolamine, HA-PE polymers that form pericellular coats around cultured dermal fibroblasts independently of CD44 or RHAMM display. We investigated the ability of these HA-PE polymers to penetrate into aged mouse skin and restore epidermal function in vivo. Topically applied Alexa647-HA-PE penetrated into the epidermis and dermis, where it associated with both keratinocytes and fibroblasts. In contrast, Alexa647-HA was largely retained in the outer cornified layer of the epidermis and quantification of fluorescence confirmed that significantly more Alexa647-HA-PE penetrated into and was retained within the epidermis than Alexa647-HA. Multiple topical applications of HA-PE to shaved mouse skin significantly stimulated basal keratinocyte proliferation and epidermal thickness compared to HA or vehicle cream alone. HA-PE had no detectable effect on keratinocyte differentiation and did not promote local or systemic inflammation. These effects of HA-PE polymers are similar to those reported for endogenous epidermal HA in youthful skin and show that topical application of HA-PE polymers can restore some of the impaired functions of aged epidermis.

  14. Hyaluronan/Tween 80-assisted synthesis of silver nanoparticles for biological application

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hui-Jun [Fudan University, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry (China); Zhang, An-Qi [Fudan University, Department of Materials Science (China); Sui, Li [University of Shanghai for Science and Technology, School of Medical Instrument and Food Engineering (China); Qian, Dong-Jin; Chen, Meng, E-mail: chenmeng@fudan.edu.cn [Fudan University, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry (China)

    2015-02-15

    Water-soluble and well-stabilized silver nanoparticles (NPs) of small size have been synthesized using hyaluronan (HA) and Tween 80 as reducing and stabilizing agents. The effect of reaction conditions on the formation process of silver NPs was studied, and an aggregative growth mechanism of the silver NPs dominated in HA/Tween 80 system at pH 12 has been proposed. The obtained Ag NPs were characterized by UV–Vis spectroscopy, transmission electron microscopy, X-ray powder diffraction, and X-ray photoelectron spectroscopy. Moreover, the stability of the HA–Tween 80-silver NPs in normal saline was also studied, and a flexible blend membrane containing chitosan, gelatin, and the HA–Tween 80-silver NPs was prepared for further biological applications. Due to the high specific surface area and improved stability of silver NPs, the chitosan–gelatin-silver membrane has shown high antibacterial activity for strains of Escherichia coli. The cell viability tests indicate that the polymer membrane is non-cytotoxic to HepG2 cells, which might be attributed to its good biocompatibility.

  15. Synthesis of hyaluronan haloacetates and biology of novel cross-linker-free synthetic extracellular matrix hydrogels.

    Science.gov (United States)

    Serban, Monica A; Prestwich, Glenn D

    2007-09-01

    Hyaluronan (HA) derivatives containing thiol-reactive electrophilic esters were prepared to react with thiol-modified macromolecules to give cross-linker-free hydrogels. Specifically, HA was converted to two haloacetate derivatives, HA bromoacetate (HABA) and HA iodoacetate (HAIA). In cytotoxicity assays, these reactive macromolecules predictably induced cell death in a dose-dependent manner. Cross-linker-free synthetic extracellular matrix (sECM) hydrogels were prepared by thiol alkylation using HAIA and HABA as polyvalent electrophiles and thiol-modified HA (CMHA-S) with or without thiol-modified gelatin (Gtn-DTPH) as polyvalent nucleophiles. When primary human fibroblasts were seeded on the surface of the sECMs containing only the electrophilic HA haloacetate and nucleophilic CMHA-S components, no significant cytoadherence was observed. Cell attachment and viability was 17% (HABA) to 30% (HAIA) lower on HA haloacetate cross-linked hydrogels than on CMHA-S that had been oxidatively cross-linked via disulfide-bonds. In contrast, sECMs that included Gtn-DTPH allowed fibroblasts to attach, spread, and proliferate. Taken together, the HA haloacetates are attractive candidates for producing cross-linker-free sECM biomaterials that can function either as anti-adhesive barriers or as cytoadhesive sECMs for cell culture in pseudo-3-D.

  16. Fabrication of Hyaluronan-Poly(vinylphosphonic acid-Chitosan Hydrogel for Wound Healing Application

    Directory of Open Access Journals (Sweden)

    Dang Hoang Phuc

    2016-01-01

    Full Text Available A new hydrogel made of hyaluronan, poly(vinylphosphonic acid, and chitosan (HA/PVPA/CS hydrogel was fabricated and characterized to be used for skin wound healing application. Firstly, the component ratio of hydrogel was studied to optimize the reaction effectiveness. Next, its microstructure was observed by light microscope. The chemical interaction in hydrogel was evaluated by nuclear magnetic resonance spectroscopy and Fourier transform-infrared spectroscopy. Then, a study on its degradation rate was performed. After that, antibacterial activity of the hydrogel was examined by agar diffusion method. Finally, in vivo study was performed to evaluate hydrogel’s biocompatibility. The results showed that the optimized hydrogel had a three-dimensional highly porous structure with the pore size ranging from about 25 µm to less than 125 µm. Besides, with a degradation time of two weeks, it could give enough time for the formation of extracellular matrix framework during remodeling stages. Furthermore, the antibacterial test showed that hydrogel has antimicrobial activity against E. coli. Finally, in vivo study indicated that the hydrogel was not rejected by the immune system and could enhance wound healing process. Overall, HA/PVPA/CS hydrogel was successfully fabricated and results implied its potential for wound healing applications.

  17. Increased concentration of hyaluronan in tears after soaking contact lenses in Biotrue multipurpose solution

    Science.gov (United States)

    Scheuer, Catherine A; Rah, Marjorie J; Reindel, William T

    2016-01-01

    Purpose This study was conducted to determine 1) the concentration of hyaluronan (HA) in the tear films of contact lens (CL) wearers versus non-CL wearers and 2) whether HA sorbed from Biotrue, an HA-containing multipurpose solution (MPS), onto senofilcon A lenses affects the concentration of HA in tears after 2 hours of wear. Patients and methods Tears of habitual CL wearers and non-CL wearers were collected on Schirmer strips at baseline and after 2 hours of wear of senofilcon A CLs that had first been either rinsed with Sensitive Eyes Saline or soaked in Biotrue MPS for 14 hours. HA concentrations were measured by enzyme-linked immunosorbent assay (ELISA) and adjusted for sample volumes. Results No difference in baseline concentrations of HA in tears was found between CL wearers and non-CL wearers (P=0.07), nor between males and females (P=0.06). However, age was significantly negatively associated with HA concentration (Peyes that had worn CLs soaked in Biotrue MPS when compared to baseline (P=0.01) or to saline-rinsed control (P=0.03). Conclusion 1) In this study population, no difference in baseline concentration of HA was observed between CL wearers and non-CL wearers, and 2) after 2 hours of wear of senofilcon A lenses that were soaked in Biotrue MPS, HA concentrations in the tear films of CL wearers increased. PMID:27784983

  18. Neocartilage formation from mesenchymal stem cells grown in type II collagen-hyaluronan composite scaffolds.

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    Yeh, Hsi-Yi; Lin, Ting-Yu; Lin, Chen-Huan; Yen, B Linju; Tsai, Ching-Lin; Hsu, Shan-Hui

    2013-01-01

    Three-dimensional (3D) collagen type II-hyaluronan (HA) composite scaffolds (CII-HA) which mimics the extracellular environment of natural cartilage were fabricated in this study. Rheological measurements demonstrated that the incorporation of HA increased the compression modulus of the scaffolds. An initial in vitro evaluation showed that scaffolds seeded with porcine chondrocytes formed cartilaginous-like tissue after 8 weeks, and HA functioned to promote the growth of chondrocytes into scaffolds. Placenta-derived multipotent cells (PDMC) and gingival fibroblasts (GF) were seeded on tissue culture polystyrene (TCPS), CII-HA films, and small intestinal submucosa (SIS) sheets for comparing their chondrogenesis differentiation potentials with those of adipose-derived adult stem cells (ADAS) and bone marrow-derived mesenchymal stem cells (BMSC). Among different cells, PDMC showed the greatest chondrogenic differentiation potential on both CII-HA films and SIS sheets upon TGF-β3 induction, followed by GF. This was evidenced by the up-regulation of chondrogenic genes (Sox9, aggrecan, and collagen type II), which was not observed for cells grown on TCPS. This finding suggested the essential role of substrate materials in the chondrogenic differentiation of PDMC and GF. Neocartilage formation was more obvious in both PDMC and GF cells plated on CII-HA composite scaffolds vs. 8-layer SIS at 28 days in vitro. Finally, implantation of PDMC/CII-HA constructs into NOD-SCID mice confirmed the formation of tissue-engineered cartilage in vivo.

  19. Mechanically strong triple network hydrogels based on hyaluronan and poly(N,N-dimethylacrylamide).

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    Tavsanli, Burak; Can, Volkan; Okay, Oguz

    2015-11-21

    Hyaluronan (HA) is a natural polyelectrolyte with distinctive biological functions. Cross-linking of HA to generate less degradable hydrogels for use in biomedical applications has attracted interest over many years. One limitation of HA hydrogels is that they are very brittle and/or easily dissolve in physiological environments, which limit their use in load-bearing applications. Herein, we describe the preparation of triple-network (TN) hydrogels based on HA and poly(N,N-dimethylacrylamide) (PDMA) of high mechanical strength by sequential gelation reactions. TN hydrogels containing 81-91% water sustain compressive stresses above 20 MPa and exhibit Young's moduli of up to 1 MPa. HA of various degrees of methacrylation was used as a multifunctional macromer for the synthesis of the brittle first-network component, while loosely cross-linked PDMA was used as the ductile, second and third network components of TN hydrogels. By tuning the methacrylation degree of HA, double-network hydrogels with a fracture stress above 10 MPa and a fracture strain of 96% were obtained. Increasing the ratio of ductile-to-brittle components via the TN approach further increases the fracture stress above 20 MPa. Cyclic mechanical tests show that, although TN hydrogels internally fracture even under small strain, the ductile components hinder macroscopic crack propagation by keeping the macroscopic gel samples together.

  20. Androgen-stimulated UDP-glucose dehydrogenase expression limits prostate androgen availability without impacting hyaluronan levels

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    Wei, Qin; Galbenus, Robert; Raza, Ashraf; Cerny, Ronald L.; Simpson, Melanie A.

    2009-01-01

    UDP-glucose dehydrogenase (UGDH) oxidizes UDP-glucose to UDP-glucuronate, an essential precursor for production of hyaluronan (HA), proteoglycans, and xenobiotic glucuronides. High levels of HA turnover in prostate cancer are correlated with aggressive progression. UGDH expression is high in the normal prostate even though HA accumulation is virtually undetectable. Thus, its normal role in the prostate may be to provide precursors for glucuronosyltransferase enzymes, which inactivate and solubilize androgens by glucuronidation. In this report, we quantified androgen dependence of UGDH, glucuronosyltransferase, and HA synthase expression. Androgen dependent and independent human prostate cancer cell lines were used to test the effects of UGDH manipulation on tumor cell growth, HA production and androgen glucuronidation. Dihydrotestosterone (DHT) increased UGDH expression ≈2.5-fold in androgen dependent cells. However, upregulation of UGDH did not affect HA synthase expression or enhance HA production. Mass spectrometric analysis showed that DHT was converted to a glucuronide, DHT-G, at a six-fold higher level in androgen dependent cells relative to androgen independent cells. The increased solubilization and elimination of DHT corresponded to slower cellular growth kinetics, which could be reversed in androgen dependent cells by treatment with a UDP-glucuronate scavenger. Collectively, these results suggest that dysregulated expression of UGDH could promote the development of androgen independent tumor cell growth by increasing available levels of intracellular androgen. PMID:19244115

  1. Genetic variation in hyaluronan metabolism loci is associated with plasma plasminogen activator inhibitor-1 concentration.

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    Lanktree, Matthew B; Johansen, Christopher T; Anand, Sonia S; Davis, A Darlene; Miller, Ruby; Yusuf, Salim; Hegele, Robert A

    2010-09-23

    Elevated plasma plasminogen activator inhibitor-1 (PAI-1) concentration is associated with cardiovascular disease risk. PAI-1 is the primary inhibitor of fibrinolysis within both the circulation and the arterial wall, playing roles in both atherosclerosis and thrombosis. To define the heritable component, subjects within the population-based SHARE (Study of Health Assessment and Risk in Ethnic groups) and SHARE-AP (Study of Health Assessment and Risk Evaluation in Aboriginal Peoples) studies, composed of Canadians of South Asian (n = 298), Chinese (n = 284), European (n = 227), and Aboriginal (n = 284) descent, were genotyped using the gene-centric Illumina HumanCVD BeadChip. After imputation, more than 150,000 single nucleotide polymorphisms (SNPs) in more than 2000 loci were tested for association with plasma PAI-1 concentration. Marginal association was observed with the PAI-1 locus itself (SERPINE1; P HABP2, HSPA1A, HYAL1, MBTPS1, TARP) were associated with PAI-1 concentration at a P HABP2) and hyaluronoglucosaminidase 1 (HYAL1), play key roles in hyaluronan metabolism, providing genetic evidence to link these pathways.

  2. Characterization of and host response to tyramine substituted-hyaluronan enriched fascia extracellular matrix

    Science.gov (United States)

    Chin, LiKang; Calabro, Anthony; Rodriguez, E. Rene; Tan, Carmela D.; Walker, Esteban

    2011-01-01

    Naturally-occurring biomaterial scaffolds derived from extracellular matrix (ECM) have been previously investigated for soft tissue repair. We propose to enrich fascia ECM with high molecular weight tyramine substituted-hyaluronan (TS-HA) to modulate inflammation associated with implantation and enhance fibroblast infiltration. As critical determinants of constructive remodeling, the host inflammatory response and macrophage polarization to TS-HA enriched fascia were characterized in a rat abdominal wall model. TS-HA treated fascia with cross-linking had a similar lymphocyte (P = 0.11) and plasma cell (P = 0.13) densities, greater macrophage (P = 0.001) and giant cell (P fascia, with or without cross-linking, exhibited a predominantly M2 pro-remodeling macrophage profile similar to water controls (P = 0.82), which is suggestive of constructive tissue remodeling. Our findings demonstrated that HA augmentation can alter the host response to an ECM, but the appropriate concentration and molecular weight needed to minimize chronic inflammation within the scaffold remains to be determined. PMID:21553156

  3. Novel enzymatically cross-linked hyaluronan hydrogels support the formation of 3D neuronal networks.

    Science.gov (United States)

    Broguiere, Nicolas; Isenmann, Luca; Zenobi-Wong, Marcy

    2016-08-01

    Hyaluronan (HA) is an essential component of the central nervous system's extracellular matrix and its high molecular weight (MW) form has anti-inflammatory and anti-fibrotic properties relevant for regenerative medicine. Here, we introduce a new hydrogel based on high MW HA which is cross-linked using the transglutaminase (TG) activity of the activated blood coagulation factor XIII (FXIIIa). These HA-TG gels have significant advantages for neural tissue engineering compared to previous HA gels. Due to their chemical inertness in the absence of FXIIIa, the material can be stored long-term, is stable in solution, and shows no cytotoxicity. The gelation is completely cell-friendly due to the specificity of the enzyme and the gelation rate can be tuned from seconds to hours at physiological pH and independently of stiffness. The gels are injectable, and attach covalently to fibrinogen and fibrin, two common bioactive components in in vitro tissue engineering, as well as proteins present in vivo, allowing the gels to covalently bind to brain or spinal cord defects. These optimal chemical and bioactive properties of HA-TG gels enabled the formation of 3D neuronal cultures of unprecedented performance, showing fast neurite outgrowth, axonal and dendritic speciation, strong synaptic connectivity in 3D networks, and rapidly-occurring and long-lasting coordinated electrical activity.

  4. Hyaluronan (Erectus(R in der Behandlung der Osteoarthritis (OA des Kniegelenks - Ergebnisse einer offenen Anwendungsbeobachtung

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    Leeb BF

    2007-01-01

    Full Text Available Ziel der Untersuchung war es, praxisrelevante Daten hinsichtlich der Wirksamkeit, Verträglichkeit und Auswirkung auf die Lebensqualität einer in Österreich neu zugelassenen Hyaluronan-Präparation (Erectus(R; MW 1.100 KD zu erhalten. Patienten und Methodik: Zu diesem Zweck wurden 204 Patienten mit OA des Kniegelenkes, Kellgren-Lawrence (KL I–III (mean 61,1 a [31 a–100 a]; mean BMI 26,9; 57,2% weiblich, 42,8 % männlich von Oktober 2005 bis April 2006 in diese offene multizentrische Anwendungsbeobachtung eingeschlossen. Die Patienten erhielten fünf Injektionen Erectus(Rintraartikulär im Abstand von einer Woche. Primärer Endpunkt war die Verbesserung des Ruheschmerzes zu Visite 5 (Woche 5. Sekundäre Endpunkte waren Verbesserung des Ruheschmerzes bei Visite 6 (Woche 13 sowie des Bewegungsschmerzes, der Beweglichkeit und der Zufriedenheit mit der Lebenssituation. Alle Parameter wurden von den Patienten anhand einer Likert-Skala (0–10 beurteilt. Darüber hinaus erfolgte die Beurteilung von Gesamtwirksamkeit, Verträglichkeit und Gesamtzufriedenheit durch Prüfarzt und PatientIn. Die statistische Auswertung erfolgte mittels T-Test und Chi-Quadrat-Test. Fehlende Werte wurden gemäß LOCF ersetzt. Ergebnisse: Der Ruheschmerz wurde von den Patienten zu Beginn mit im Mittel 4,68 angegeben und verbesserte sich auf 2,04 bei Visite 5 bzw. auf 1,8 bei Visite 6 (p 0,01. Die Verbesserung war bei Patienten mit KL Grad I am stärksten und bei KL III am geringsten ausgeprägt. Die subjektive Beurteilung der Beweglichkeit sowie die Zufriedenheit, mit dem aktuellen Krankheitszustand längerfristig leben zu müssen, verbesserte sich ebenfalls signifikant (p 0,01, wobei dabei interessanterweise die stärksten Veränderungen bei Patienten mit KL III festzustellen waren. Patienten und Behandler beurteilten die globale Wirksamkeit parallel positiv, wie auch die Verträglichkeit. Die Beurteilung der Gesamtzufriedenheit nach einem Schulnotensystem (1–5 ergab

  5. Incorporation of pentraxin 3 into hyaluronan matrices is tightly regulated and promotes matrix cross-linking.

    Science.gov (United States)

    Baranova, Natalia S; Inforzato, Antonio; Briggs, David C; Tilakaratna, Viranga; Enghild, Jan J; Thakar, Dhruv; Milner, Caroline M; Day, Anthony J; Richter, Ralf P

    2014-10-31

    Mammalian oocytes are surrounded by a highly hydrated hyaluronan (HA)-rich extracellular matrix with embedded cumulus cells, forming the cumulus cell·oocyte complex (COC) matrix. The correct assembly, stability, and mechanical properties of this matrix, which are crucial for successful ovulation, transport of the COC to the oviduct, and its fertilization, depend on the interaction between HA and specific HA-organizing proteins. Although the proteins inter-α-inhibitor (IαI), pentraxin 3 (PTX3), and TNF-stimulated gene-6 (TSG-6) have been identified as being critical for COC matrix formation, its supramolecular organization and the molecular mechanism of COC matrix stabilization remain unknown. Here we used films of end-grafted HA as a model system to investigate the molecular interactions involved in the formation and stabilization of HA matrices containing TSG-6, IαI, and PTX3. We found that PTX3 binds neither to HA alone nor to HA films containing TSG-6. This long pentraxin also failed to bind to products of the interaction between IαI, TSG-6, and HA, among which are the covalent heavy chain (HC)·HA and HC·TSG-6 complexes, despite the fact that both IαI and TSG-6 are ligands of PTX3. Interestingly, prior encounter with IαI was required for effective incorporation of PTX3 into TSG-6-loaded HA films. Moreover, we demonstrated that this ternary protein mixture made of IαI, PTX3, and TSG-6 is sufficient to promote formation of a stable (i.e. cross-linked) yet highly hydrated HA matrix. We propose that this mechanism is essential for correct assembly of the COC matrix and may also have general implications in other inflammatory processes that are associated with HA cross-linking. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  6. Visualization of a hyaluronan network on the surface of silicone-hydrogel materials

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    Wygladacz KA

    2016-07-01

    Full Text Available Katarzyna A Wygladacz, Daniel J Hook Vision Care, Bausch & Lomb Incorporated, Rochester, NY, USA Abstract: Biotrue multipurpose solution (MPS is a bioinspired disinfecting and conditioning solution that includes hyaluronic acid (HA as a natural wetting agent. Previous studies demonstrated that HA sorbed from Biotrue MPS on both conventional and silicone hydrogel (SiHy contact lens materials; an in vitro simulated-wear test validated the presence of HA on the lens surfaces for as long as 20 hours. In this study, the morphology and distribution of HA sorbed from both Biotrue and pure HA solution on SiHy contact lens surfaces was examined. Atomic force microscopy imaging was used to illustrate the topography of fresh SiHy contact lens materials before and after incubation with 0.1% (w/v HA solution. The distribution, as well as fine details of the HA network, were resolved by first staining HA with Gram’s safranin, then imaging with confocal laser-scanning microscopy and differential interference-contrast microscopy. In this approach, SiHy materials take up the dye (safranin nonspecifically, such that the resultant safranin–HA complex appears dim against the fluorescent lens background. Balafilcon A was chosen as the representative of glassy SiHy lenses that require postpolymerization plasma treatment to increase wettability. Senofilcon A and samfilcon A were chosen as representatives of SiHy materials fabricated with an internal wetting agent. A confluent and dim HA–safranin network was observed adhered to balafilcon A, senofilcon A, and samfilcon A lens surfaces incubated with either 0.1% (w/v HA solution or Biotrue MPS. Therefore, the conditioning function provided by Biotrue MPS may be in part explained by the presence of the HA humectant layer that readily sorbs on the various types of SiHy contact lens materials. Keywords: contact lens, hyaluronan, MPS, AFM, CLSM, DIC microscopy

  7. Viscoelastic Properties of Hyaluronan in Physiological Conditions [version 1; referees: 2 approved

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    Mary K. Cowman

    2015-08-01

    Full Text Available Hyaluronan (HA is a high molecular weight glycosaminoglycan of the extracellular matrix (ECM, which is particularly abundant in soft connective tissues. Solutions of HA can be highly viscous with non-Newtonian flow properties. These properties affect the movement of HA-containing fluid layers within and underlying the deep fascia. Changes in the concentration, molecular weight, or even covalent modification of HA in inflammatory conditions, as well as changes in binding interactions with other macromolecules, can have dramatic effects on the sliding movement of fascia. The high molecular weight and the semi-flexible chain of HA are key factors leading to the high viscosity of dilute solutions, and real HA solutions show additional nonideality and greatly increased viscosity due to mutual macromolecular crowding. The shear rate dependence of the viscosity, and the viscoelasticity of HA solutions, depend on the relaxation time of the molecule, which in turn depends on the HA concentration and molecular weight. Temperature can also have an effect on these properties. High viscosity can additionally affect the lubricating function of HA solutions. Immobility can increase the concentration of HA, increase the viscosity, and reduce lubrication and gliding of the layers of connective tissue and muscle. Over time, these changes can alter both muscle structure and function. Inflammation can further increase the viscosity of HA-containing fluids if the HA is modified via covalent attachment of heavy chains derived from Inter-α-Inhibitor. Hyaluronidase hydrolyzes HA, thus reducing its molecular weight, lowering the viscosity of the extracellular matrix fluid and making outflow easier. It can also disrupt any aggregates or gel-like structures that result from HA being modified. Hyaluronidase is used medically primarily as a dispersion agent, but may also be useful in conditions where altered viscosity of the fascia is desired, such as in the treatment of

  8. Inhibition of hyaluronan synthesis reduces versican and fibronectin levels in trabecular meshwork cells.

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    Kate E Keller

    Full Text Available Hyaluronan (HA is a major component of the extracellular matrix (ECM and is synthesized by three HA synthases (HAS. Similarities between the HAS2 knockout mouse and the hdf mutant mouse, which has a mutation in the versican gene, suggest that HA and versican expression may be linked. In this study, the relationship between HA synthesis and levels of versican, fibronectin and several other ECM components in trabecular meshwork cells from the anterior segment of the eye was investigated. HA synthesis was inhibited using 4-methylumbelliferone (4MU, or reduced by RNAi silencing of each individual HAS gene. Quantitative RT-PCR and immunoblotting demonstrated a reduction in mRNA and protein levels of versican and fibronectin. Hyaluronidase treatment also reduced versican and fibronectin levels. These effects could not be reversed by addition of excess glucose or glucosamine or exogenous HA to the culture medium. CD44, tenascin C and fibrillin-1 mRNA levels were reduced by 4MU treatment, but SPARC and CSPG6 mRNA levels were unaffected. Immunostaining of trabecular meshwork tissue after exposure to 4MU showed an altered localization pattern of HA-binding protein, versican and fibronectin. Reduction of versican by RNAi silencing did not affect HA concentration as assessed by ELISA. Together, these data imply that HA concentration affects synthesis of certain ECM components. Since precise regulation of the trabecular meshwork ECM composition and organization is required to maintain the aqueous humor outflow resistance and intraocular pressure homeostasis in the eye, coordinated coupling of HA levels and several of its ECM binding partners should facilitate this process.

  9. Visible light crosslinking of methacrylated hyaluronan hydrogels for injectable tissue repair.

    Science.gov (United States)

    Fenn, Spencer L; Oldinski, Rachael A

    2016-08-01

    Tissue engineering hydrogels are primarily cured in situ using ultraviolet (UV) radiation which limits the use of hydrogels as drug or cell carriers. Visible green light activated crosslinking systems are presented as a safe alternative to UV photocrosslinked hydrogels, without compromising material properties such as viscosity and stiffness. The objective of this study was to fabricate and characterize photocrosslinked hydrogels with well-regulated gelation kinetics and mechanical properties for the repair or replacement of soft tissue. An anhydrous methacrylation of hyaluronan (HA) was performed to control the degree of modification (DOM) of HA, verified by (1) H-NMR spectroscopy. UV-activated crosslinking was compared to visible green light activated crosslinking. While the different photocrosslinking techniques resulted in varied crosslinking times, comparable mechanical properties of UV and green light activated crosslinked hydrogels were achieved using each photocrosslinking method by adjusting time of light exposure. Methacrylated HA (HA-MA) hydrogels of varying molecular weight, DOM, and concentration exhibited compressive moduli ranging from 1 kPa to 116 kPa, for UV crosslinking, and 3 kPa to 146 kPa, for green light crosslinking. HA-MA molecular weight and concentration were found to significantly influence moduli values. HA-MA hydrogels did not exhibit any significant cytotoxic effects toward human mesenchymal stem cells. Green light activated crosslinking systems are presented as a viable method to form natural-based hydrogels in situ. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1229-1236, 2016.

  10. Specific sizes of hyaluronan oligosaccharides stimulate fibroblast migration and excisional wound repair.

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    Cornelia Tolg

    Full Text Available The extracellular matrix polysaccharide hyaluronan (HA plays a key role in both fibrotic and regenerative tissue repair. Accumulation of high molecular weight HA is typical of regenerative repair, which is associated with minimal inflammation and fibrosis, while fragmentation of HA is typical of postnatal wounds, which heal in the presence of inflammation and transient fibrosis. It is generally considered that HA oligosaccharides and fragments of a wide size range support these processes of adult, fibrotic wound repair yet the consequences of sized HA fragments/oligosaccharides to each repair stage is not well characterized. Here, we compared the effects of native HA, HA oligosaccharide mixtures and individual sizes (4-10 mer oligosaccharides, 5 and, 40 kDa of HA oligosaccharides and fragments, on fibroblast migration in scratch wound assays and on excisional skin wound repair in vivo. We confirm that 4-10 mer mixtures significantly stimulated scratch wound repair and further report that only the 6 and 8 mer oligosaccharides in this mixture are responsible for this effect. The HA 6 mer promoted wound closure, accumulation of wound M1 and M2 macrophages and the M2 cytokine TGFβ1, but did not increase myofibroblast differentiation. The effect of 6 mer HA on wound closure required both RHAMM and CD44 expression. In contrast, The 40 kDa HA fragment inhibited wound closure, increased the number of wound macrophages but had no effect on TGFβ1 accumulation or subsequent fibrosis. These results show that specific sizes of HA polymer have unique effects on postnatal wound repair. The ability of 6 mer HA to promote wound closure and inflammation resolution without increased myofibroblast differentiation suggests that this HA oligosaccharide could be useful for treatment of delayed or inefficient wound repair where minimal fibrosis is advantageous.

  11. Three-year clinical outcome after chondrocyte transplantation using a hyaluronan matrix for cartilage repair

    Energy Technology Data Exchange (ETDEWEB)

    Nehrer, S. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)]. E-mail: stefan.nehrer@meduniwien.ac.at; Domayer, S. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Dorotka, R. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Schatz, K. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Bindreiter, U. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria); Kotz, R. [Department of Orthopedics, Medical University of Vienna, Waehringer Guertel 18-20, A-1090 Vienna (Austria)

    2006-01-15

    Repair of articular cartilage represents a significant clinical problem and although various new techniques - including the use of autologous chondrocytes - have been developed within the last century the clinical efficacy of these procedures is still discussed controversially. Although autologous chondrocyte transplantation (ACT) has been widely used with success, it has several inherent limitations, including its invasive nature and problems related to the use of the periosteal flap. To overcome these problems autologous chondrocytes transplantation combined with the use of biodegradable scaffolds has received wide attention. Among these, a hyaluronan-based scaffold has been found useful for inducing hyaline cartilage regeneration. In the present study, we have investigated the mid-term efficacy and safety of Hyalograft[reg] C grafts in a group of 36 patients undergoing surgery for chronic cartilage lesions of the knee. Clinical Outcome was assessed prospectively before and at 12, 24, and 36 months after surgery. No major adverse events have been reported during the 3-year follow-up. Significant improvements of the evaluated scores were observed (P < 0.02) at 1 year and a continued increase of clinical performance was evident at 2 and 3 years follow-up. Patients under 30 years of age with single lesions showed statistically significant improvements at all follow-up visits compared to those over 30 with multiple defects (P < 0.01). Hyalograft[reg] C compares favorably with classic ACT and is particularly indicated in younger patients with single lesions. The graft can be implanted through a miniarthrotomy and needs no additional fixation with sutures except optional fibrin gluing at the defect borders. These results suggest that Hyalograft[reg] C is a valid alternative to ACT.

  12. Peritoneal Adhesion and Angiogenesis in Ovarian Carcinoma Are Inversely Regulated by Hyaluronan: The Role of Gonadotropins

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    Yael Chagit Tzuman

    2010-01-01

    Full Text Available Ovarian carcinoma is the leading cause of death among gynecologic cancers. Although transformation of the outer ovarian epithelium was linked with ovulation, the disease is significantly more prevalent and severe in postmenopausal women. We postulated that menopause could augment ovarian cancer progression through the effects of gonadotropins on multifocal seeding to the mesothelial layer lining the peritoneum. This seeding is mediated by integrins as well as by CD44 interaction with hyaluronan (HA. Here, we report the effect of gonadotropins on HA synthesis and degradation and on peritoneal adhesion. A significant concentration- and time-dependent induction in expression levels of HA synthases (HASs and hyaluronidases (Hyals was observed in vitro on stimulation of human epithelial ovarian carcinoma cells by gonadotropins. Hormonal regulation of HA-mediated adhesion was manifested in vivo as well, by fluorescence microscopy of stained MLS multicellular tumor spheroids. The number of spheroids adhered to the mesothelium of ovariectomized CD-1 nude mice 9.5 hours after intraperitoneal insertion was significantly higher than in nonovariectomized mice. Inhibition of HA synthesis by 6-diazo-5-oxo-1-norleucine (DON both in spheroids and ovariectomized mice significantly reduced the number of adhered spheroids. Thus, the change in the hormonal environment during menopause assists in HA-dependent adherence of ovarian cancer spheroids onto the peritoneum. However, HA is antiangiogenic and it can significantly suppress tumor progression. Accordingly, angiogenesis of the adhered spheroids was significantly elevated in DON-treated tumors. These results can explain the selective pressure that can lead to simultaneously increased tumor expression of both HASs and Hyals.

  13. Dietary flavonoid fisetin increases abundance of high-molecular-mass hyaluronan conferring resistance to prostate oncogenesis.

    Science.gov (United States)

    Lall, Rahul K; Syed, Deeba N; Khan, Mohammad Imran; Adhami, Vaqar M; Gong, Yuansheng; Lucey, John A; Mukhtar, Hasan

    2016-09-01

    We and others have shown previously that fisetin, a plant flavonoid, has therapeutic potential against many cancer types. Here, we examined the probable mechanism of its action in prostate cancer (PCa) using a global metabolomics approach. HPLC-ESI-MS analysis of tumor xenografts from fisetin-treated animals identified several metabolic targets with hyaluronan (HA) as the most affected. Efficacy of fisetin on HA was then evaluated in vitro and also in vivo in the transgenic TRAMP mouse model of PCa. Size exclusion chromatography-multiangle laser light scattering (SEC-MALS) was performed to analyze the molar mass (Mw) distribution of HA. Fisetin treatment downregulated intracellular and secreted HA levels both in vitro and in vivo Fisetin inhibited HA synthesis and degradation enzymes, which led to cessation of HA synthesis and also repressed the degradation of the available high-molecular-mass (HMM)-HA. SEC-MALS analysis of intact HA fragment size revealed that cells and animals have more abundance of HMM-HA and less of low-molecular-mass (LMM)-HA upon fisetin treatment. Elevated HA levels have been shown to be associated with disease progression in certain cancer types. Biological responses triggered by HA mainly depend on the HA polymer length where HMM-HA represses mitogenic signaling and has anti-inflammatory properties whereas LMM-HA promotes proliferation and inflammation. Similarly, Mw analysis of secreted HA fragment size revealed less HMM-HA is secreted that allowed more HMM-HA to be retained within the cells and tissues. Our findings establish that fisetin is an effective, non-toxic, potent HA synthesis inhibitor, which increases abundance of antiangiogenic HMM-HA and could be used for the management of PCa. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. Growth factor PDGF-BB stimulates cultured cardiomyocytes to synthesize the extracellular matrix component hyaluronan.

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    Urban Hellman

    Full Text Available BACKGROUND: Hyaluronan (HA is a glycosaminoglycan located in the interstitial space which is essential for both structural and cell regulatory functions in connective tissue. We have previously shown that HA synthesis is up-regulated in a rat model of experimental cardiac hypertrophy and that cardiac tissue utilizes two different HA synthases in the hypertrophic process. Cardiomyocytes and fibroblasts are two major cell types in heart tissue. The fibroblasts are known to produce HA, but it has been unclear if cardiomyocytes share the same feature, and whether or not the different HA synthases are activated in the different cell types. METHODOLOGY/PRINCIPAL FINDINGS: This study shows, for the first time that cardiomyocytes can produce HA. Cardiomyocytes (HL-1 and fibroblasts (NIH 3T3 were cultivated in absence or presence of the growth factors FGF2, PDGF-BB and TGFB2. HA concentration was quantified by ELISA, and the size of HA was estimated using dynamic light scattering. Cardiomyocytes synthesized HA but only when stimulated by PDGF-BB, whereas fibroblasts synthesized HA without addition of growth factors as well as when stimulated by any of the three growth factors. When fibroblasts were stimulated by the growth factors, reverse dose dependence was observed, where the highest dose induced the least amount of HA. With the exception of TGFB2, a trend of reverse dose dependence of HA size was also observed. CONCLUSIONS/SIGNIFICANCE: Co-cultivation of cardiomyocytes and fibroblasts (80%/20% increased HA concentration far more that can be explained by HA synthesis by the two cell types separately, revealing a crosstalk between cardiomyocytes and fibroblasts that induces HA synthesis. We conclude that dynamic changes of the myocardium, such as in cardiac hypertrophy, do not depend on the cardiomyocyte alone, but are achieved when both cardiomyocytes and fibroblasts are present.

  15. Mechanical Properties of Tyramine Substituted-Hyaluronan Enriched Fascia Extracellular Matrix

    Science.gov (United States)

    Chin, LiKang; Calabro, Anthony; Walker, Esteban; Derwin, Kathleen A.

    2011-01-01

    Naturally-occurring biomaterial scaffolds derived from extracellular matrix (ECM) have been the topic of recent investigation in the context of rotator cuff tendon repair. We previously reported a method to treat fascia ECM with high molecular weight tyramine substituted-hyaluronan (TS-HA) for use as a tendon augmentation scaffold. The presence of cross-linked TS-HA in fascia was associated with an increased macrophage and giant cell response compared to water treated controls after implantation in a rat abdominal wall model. The objective of this study was to determine the extent to which TS-HA treatment was associated with mechanical property changes of fascia after implantation in the rat model. Fascia samples in all groups demonstrated time-dependent decreases in mechanical properties. TS-HA treated fascia with cross-linking exhibited a lower toe modulus, a trend toward lower toe stiffness, and a higher transition strain than water treated controls not only after implantation, but also at time zero. TS-HA treatment, with or without cross-linking, had no significant effect on time-zero or post-implantation load relaxation ratio, load relaxation rate, linear-region stiffness, or linear-region modulus. Our findings demonstrated that the particular TS-HA treatment employed in this study decreased the low-load elastic mechanical properties of fascia ECM, in keeping with the heightened macrophage and giant cell host response seen previously. This work provides a starting point and guidance for investigating alternative HA treatment strategies. PMID:22238019

  16. Lentiviral-mediated over-expression of hyaluronan synthase-1 (HAS-1) decreases the cellular inflammatory response and results in regenerative wound repair

    NARCIS (Netherlands)

    Caskey, Robert C.; Allukian, Myron; Lind, Robert C.; Herdrich, Benjamin J.; Xu, Junwang; Radu, Antoneta; Mitchell, Marc E.; Liechty, Kenneth W.

    2013-01-01

    Fetal wounds have been found to have increased levels of high-molecular-weight hyaluronan (HMW-HA) compared with those of adults. The primary enzyme responsible for producing HMW-HA is hyaluronic acid synthase-1 (HAS-1). We hypothesized that over-expression of HAS-1 in adult dermal wounds would decr

  17. One intra-articular injection of hyaluronan prevents cell death and improves cell metabolism in a model of injured articular cartilage in the rabbit

    NARCIS (Netherlands)

    Jansen, Edwin J. P.; Ernans, Pieter J.; Douw, Conny M.; Guidemond, Nick A.; Van Rhijn, Lodewijk W.; Bulstra, Sjoerd K.; Kuijer, Roell

    2008-01-01

    The purpose of this study was to determine the effect of one intra-articular injection of hyaluronan on chondrocyte death and metabolism in injured cartilage. Twenty-three 6-month-old rabbits received partial-thickness articular cartilage defects created on each medial femoral condyle. In order to e

  18. Hyaluronan protects against cartilage damage by decreasing stiffness and changing3-D microarchitecture of subchondral bone in guinea pig primary osteoarthrosis

    DEFF Research Database (Denmark)

    Ding, Ming

    Introduction: Hyaluronan (HA) is a biologic material, and a major component of synovial fluid. HA has received increasing interest as a potential agent of therapeutic intervention in osteoarthrosis (OA). High molecular weight HA has been shown to reduce arthritic lesions in experimental animal...

  19. Both Hyaluronan and Collagen Type II Keep Proteoglycan 4 (Lubricin) at the Cartilage Surface in a Condition That Provides Low Friction during Boundary Lubrication

    NARCIS (Netherlands)

    Majd, Sara Ehsani; Kuijer, Roel; Koewitsch, Alexander; Groth, Thomas; Schmidt, Tannin A.; Sharma, Prashant K.

    2014-01-01

    Wear resistant and ultralow friction in synovial joints is the outcome of a sophisticated synergy between the major macromolecules of the synovial fluid, e.g., hyaluronan (HA) and proteoglycan 4 (PRG4), with collagen type II fibrils and other non-collagenous macromolecules of the cartilage superfici

  20. Hyaluronan synthase 3 mediated oncogenic action through forming inter-regulation loop with tumor necrosis factor alpha in oral cancer

    Science.gov (United States)

    Kuo, Yi-Zih; Fang, Wei-Yu; Huang, Cheng-Chih; Tsai, Sen-Tien; Wang, Yi-Ching; Yang, Chih-Li; Wu, Li-Wha

    2017-01-01

    Hyaluronan (HA) is a major extracellular matrix component. However, its role and mediation in oral cancer remains elusive. Hyaluronan synthase 3 (HAS3), involved in pro-inflammatory short chain HA synthesis, was the predominant synthase in oral cancer cells and tissues. HAS3 overexpression significantly increased oral cancer cell migration, invasion and xenograft tumorigenesis accompanied with the increased expression of tumor necrosis factor alpha (TNF-α) and monocyte chemoattractant protein 1 (MCP-1). Conversely, HAS3 depletion abrogated HAS3-mediated stimulation. HAS3 induced oncogenic actions partly through activating EGFR-SRC signaling. HAS3-derived HA release into extracellular milieu enhanced transendothelial monocyte migration and MCP-1 expression, which was attenuated by anti-HAS3 antibodies or a HAS inhibitor, 4-Methylumbelliferone (4-MU). The NF-κB-binding site III at -1692 to -1682 bp upstream from the transcript 1 start site in HAS3 proximal promoter was the most responsive to TNF-α-stimulated transcription. ChIP-qPCR analysis confirmed the highest NF-κB-p65 enrichment on site III. Increased HAS3 mRNA expression was negatively correlated with the overall survival of oral cancer patients. A concomitant increase of TNF-α, a stimulus for HAS3 expression, with HAS3 expression was not only associated with lymph node metastasis but also negated clinical outcome. Together, HAS3 and TNF-α formed an inter-regulation loop to enhance tumorigenesis in oral cancer. PMID:28107185

  1. Evidence for clustered mannose as a new ligand for hyaluronan-binding protein (HABP1) from human fibroblasts

    Indian Academy of Sciences (India)

    Rajeev Kumar; Nirupam Roy Choudhury; Dinakar M Salunke; K Datta

    2001-09-01

    We have earlier reported that overexpression of the gene encoding human hyaluronan-binding protein (HABP1) is functionally active, as it binds specifically with hyaluronan (HA). In this communication, we confirm the collapse of the filamentous and branched structure of HA by interaction with increasing concentrations of recombinant-HABP1 (rHABP1). HA is the reported ligand of rHABP1. Here, we show the affinity of rHABP1 towards D-mannosylated albumin (DMA) by overlay assay and purification using a DMA affinity column. Our data suggests that DMA is another ligand for HABP1. Furthermore, we have observed that DMA inhibits the binding of HA in a concentration-dependent manner, suggesting its multiligand affinity amongst carbohydrates. rHABP1 shows differential affinity towards HA and DMA which depends on pH and ionic strength. These data suggest that affinity of rHABP1 towards different ligands is regulated by the microenvironment.

  2. The hyaluronan and proteoglycan link proteins: Organizers of the brain extracellular matrix and key molecules for neuronal function and plasticity.

    Science.gov (United States)

    Oohashi, Toshitaka; Edamatsu, Midori; Bekku, Yoko; Carulli, Daniela

    2015-12-01

    The hyaluronan and proteoglycanbinding link protein (Hapln) is a key molecule in the formation and control of hyaluronan-based condensed perineuronal matrix in the adult brain. This review summarizes the recent advances in understanding the role of Haplns in the formation and control of two distinct types of perineuronal matrices, one for "classical" PNN and the other for the specialized extracellular matrix (ECM) at the node of Ranvier in the central nervous system (CNS). We introduce the structural components of each ECM organization including the basic concept of supramolecular structure named "HLT model". We furthermore summarize the developmental and physiological role of perineuronal ECMs from the studies of Haplns and related molecules. Finally, we also discuss the potential mechanism modulating PNNs in the adult CNS. This layer of organized matrices may exert a direct effect via core protein or sugar moiety from the structure or by acting as a binding site for biologically active molecules, which are important for neuronal plasticity and saltatory conduction. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Local delivery of hyaluronan as an adjunct to scaling and root planing in the treatment of chronic periodontitis.

    Science.gov (United States)

    Johannsen, Annsofi; Tellefsen, Monica; Wikesjö, Ulf; Johannsen, Gunnar

    2009-09-01

    The aim of the present study was to evaluate the adjunctive effect of the local application of a hyaluronan gel to scaling and root planing in the treatment of chronic periodontitis. Twelve patients with chronic periodontitis were recruited to participate in a study with a split-mouth design and provided informed consent. Plaque formation and bleeding on probing were evaluated pretreatment (baseline) and at 1, 4, and 12 weeks post-treatment. Probing depths and attachment levels were evaluated at baseline and at 12 weeks. The patients received full-mouth scaling and root planing. A hyaluronan gel was administered subgingivally in the test sites at baseline and after 1 week. Significant differences between test and control were evaluated using the paired t test, repeated-measures analysis of variance (Wilks lambda), and a non-parametric Wilcoxon signed-rank test. A significant reduction in bleeding on probing scores and probing depths was observed in both groups at 12 weeks (P scaling and root planing may have a beneficial effect on periodontal health in patients with chronic periodontitis.

  4. Are sperm DNA fragmentation, hyperactivation, and hyaluronan-binding ability predictive for fertilization and embryo development in in vitro fertilization and intracytoplasmic sperm injection?

    Science.gov (United States)

    Pregl Breznik, Barbara; Kovačič, Borut; Vlaisavljević, Veljko

    2013-04-01

    To determine the diagnostic value of the following sperm function tests in predicting the fertilizing ability of spermatozoa in conventional in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI): hyaluronan-binding assay (HBA), DNA fragmentation (Halosperm), and hyperactivity. Prospective study. University medical center. 133 couples undergoing infertility treatment with IVF/ICSI. Analysis of sperm DNA fragmentation, hyaluronan-binding ability, and hyperactivation on washed semen samples used for the insemination of oocytes. Correlation between the results of sperm function tests and the fertilization rate (FR) or embryo quality (EQ) after IVF and ICSI. Comparison of the sperm DNA fragmentation, hyperactivation, and hyaluronan binding ability between cycles with less than 50% (group 1) and more than 50% (group 2) of oocytes fertilized after IVF. Both FR and EQ in IVF cycles negatively correlated with sperm DNA fragmentation. Furthermore, a positive correlation was observed between FR and hyaluronan-binding ability or induced hyperactivity. The semen samples from the IVF cycles with low FR (group 1) were characterized by statistically significantly higher sperm DNA fragmentation and lower hyaluronan-binding ability in comparison with semen samples from the group with high levels of fertilization (group 2). In ICSI cycles, no relationship was found between sperm function tests and FR or EQ. The Halosperm test, the HBA test, and induced hyperactivity are useful in predicting the ability of spermatozoa to fertilize oocytes in IVF and are helpful in distinguishing semen samples suitable for IVF or ICSI. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  5. Hyaluronan microgel as a potential carrier for protein sustained delivery by tailoring the crosslink network

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Chunhong [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Zhao, Jianhao, E-mail: jhzhao@jnu.edu.cn [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China); Tu, Mei; Zeng, Rong; Rong, Jianhua [Department of Materials Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China)

    2014-03-01

    Hyaluronan (HA) microgels with different crosslink network, i.e. HGPs-1, HGPs-1.5, HGPs-3, HGPs-6 and HGPs-15, were synthesized using divinyl sulfone (DVS) as the crosslinker in an inverse microemulsion system for controlling the sustained delivery of bovine serum albumin (BSA). With increasing the crosslinker content, the average particle size slightly increased from 1.9 ± 0.3 μm to 3.6 ± 0.5 μm by dynamic laser scattering analysis. However, the crosslinker content had no significant effect on the morphology of HA microgels by scanning and transmission electron microscopes. Fourier transform infrared spectroscopy and elemental analysis proved more sulfur participated in the crosslink reaction when raising the crosslinker amount. The water swelling test confirmed the increasing crosslink density with the crosslinker content by calculating the average molecular weight between two crosslink points to be 8.25 ± 2.51 × 10{sup 5}, 1.26 ± 0.43 × 10{sup 5}, 0.96 ± 0.09 × 10{sup 5}, 0.64 ± 0.03 × 10{sup 5}, and 0.11 ± 0.01 × 10{sup 5} respectively. The degradation of HA microgels by hyaluronidase slowed down by enhancing the crosslink density, only about 5% of HGPs-15 was degraded as opposed to over 90% for HGPs-1. BSA loading had no obvious influence on the surface morphology of HA microgels but seemed to induce their aggregation. The increase of crosslink density decreased the BSA loading capacity but facilitated its long-term sustained delivery. When the molar ratio of DVS to repeating unit of HA reached 3 or higher, similar delivery profiles were obtained. Among all these HA microgels, HGPs-3 was the optimal carrier for BSA sustained delivery in this system because it possessed both high BSA loading capacity and long-term delivery profile simultaneously. - Highlights: • HA microgels with different crosslink densities were prepared. • The crosslinker content had little effect on the morphology and size of HA microgels. • The crosslink density

  6. Selective hyaluronan-CD44 signaling promotes miRNA-21 expression and interacts with vitamin D function during cutaneous squamous cell carcinomas progression following UV irradiation

    Directory of Open Access Journals (Sweden)

    Lilly YW Bourguignon

    2015-05-01

    Full Text Available Hyaluronan (HA, the major extracellular matrix component, is often anchored to CD44 isoforms, a family of structurally/functionally important cell surface receptors. Our recent results indicate that UV irradiation (UVR-induced cutaneous squamous cell carcinomas (SCC overexpress a variety of CD44 variant isoforms (CD44v, with different CD44v isoforms appear to confer malignant SCC properties. UVR also stimulates HA degradation in epidermal keratinocytes. Both large HA polymers and their UVR-induced catabolic products (small HA selectively activate CD44 isoform-mediated cellular signaling in normal keratinocytes and SCC cells, with all of the downstream processes being mediated by RhoGTPases (e.g., RhoA and Rac1. Importantly, we found that the hormonally active form of vitamin D (1,25(OH2D3 not only prevents the UVR-induced small HA activation of abnormal keratinocyte behavior and SCC progression, but also enhances large HA stimulation of normal keratinocyte activities and epidermal function(s. Furthermore, we found that HA and its UVR-induced catabolic products (e.g., large and small HA selectively activate CD44-mediated Rac and RhoA signaling. Specifically, large HA-CD44 interaction promotes Rac/PKNγ-dependent normal keratinocyte differentiation, DNA repair and keratinocyte survival. Conversely, small HA-CD44v isoform interaction stimulates RhoA/ROK-dependent NFκB signaling and microRNA-21 (miR-21 production, leading to inflammation, proliferation (following acute UVR response and SCC progression (following chronic UVR exposure. Active vitamin D inhibits small HA-CD44v-mediated RhoA/ROK signaling and SCC progression; and it also enhances large HA-CD44-mediated differentiation, DNA repair and normal epidermal function. Selective applications of large HA and vitamin D will be used to improve the UVR-induced HA (small vs. large HA-CD44 isoform interaction with RhoGTPase signaling and skin inflammation as a potential therapeutic treatment for skin

  7. Systemic delivery of siRNA by hyaluronan-functionalized calcium phosphate nanoparticles for tumor-targeted therapy

    Science.gov (United States)

    Qiu, Chong; Wei, Wei; Sun, Jing; Zhang, Hai-Tao; Ding, Jing-Song; Wang, Jian-Cheng; Zhang, Qiang

    2016-06-01

    In this study, hyaluronan (HA)-functionalized calcium phosphate nanoparticles (CaP-AHA/siRNA NPs) were developed for an injectable and targetable delivery of siRNA, which were prepared by coating the alendronate-hyaluronan graft polymer (AHA) around the surface of calcium phosphate-siRNA co-precipitates. The prepared CaP-AHA/siRNA NPs had a uniform spherical core-shell morphology with an approximate size of 170 nm and zeta potential of -12 mV. The coating of hydrophilic HA improved the physical stability of nanoparticles over one month due to the strong interactions between phosphonate and calcium. In vitro experiments demonstrated that the negatively charged CaP-AHA/siRNA NPs could effectively deliver EGFR-targeted siRNA into A549 cells through CD44-mediated endocytosis and significantly down-regulate the level of EGFR expression. Also, the internalized CaP-AHA/siRNA NPs exhibited a pH-responsive release of siRNA, indicating that the acidification of lysosomes probably facilitated the disassembling of nanoparticles and the resultant ions sharply increased the inner osmotic pressure and thus expedited the release of siRNA from late lysosomes into the cytoplasm. Furthermore, in vivo tumor therapy demonstrated that high accumulation of CaP-AHA/siEGFR NPs in tumor led to a significant tumor growth inhibition with a specific EGFR gene silencing effect after intravenous administration in nude mice xenografted with A549 tumor, along with a negligible body weight loss. These results suggested that the CaP-AHA/siRNA NPs could be an effective and safe systemic siRNA delivery system for a RNAi-based tumor targeted therapy strategy.In this study, hyaluronan (HA)-functionalized calcium phosphate nanoparticles (CaP-AHA/siRNA NPs) were developed for an injectable and targetable delivery of siRNA, which were prepared by coating the alendronate-hyaluronan graft polymer (AHA) around the surface of calcium phosphate-siRNA co-precipitates. The prepared CaP-AHA/siRNA NPs had a uniform

  8. EFFECTS OF HYALURONAN ON THREE-DIMENSIONAL MICROARCHITECTURE OF SUBCHONDRAL BONE TISSUES IN GUINEA PIG PRIMARY OSTEOARTHROSIS

    DEFF Research Database (Denmark)

    Ding, Ming

    Introduction: It is not known whether hyaluronan (HA) has any effect on the underlying subchondral bone tissues. This study was to investigate the effects of high molecular weight HA (1.5x106 Daltons) intra-articular injection on subchondral bone tissues. Methods: Fifty-six male guinea pigs (6......-term study, these latter changes were more pronounced, with an additionally significant decrease in connectivity and bone surface density. HA groups had greater bone mineral concentration and mineral density, lower collagen to mineral ratio, and preserved the mechanical properties of cancellous bone....... The effects of HA on cartilage and subchondral bone were maintained when HA treatment was discontinued. Discussion: Significant positive effects of high molecular weight HA on the articular cartilage and subchondral bone tissues were seen. HA protects against OA-related cartilage degradation to almost normal...

  9. Vitrification is not superior to rapid freezing of normozoospermic spermatozoa: effects on sperm parameters, DNA fragmentation and hyaluronan binding.

    Science.gov (United States)

    Agha-Rahimi, Azam; Khalili, Mohammad Ali; Nabi, Ali; Ashourzadeh, Sareh

    2014-03-01

    Human sperm vitrification is a new cryopreservation method. This study compared the effects of rapid freezing and vitrification on various sperm parameters, hyaluronan-binding assay and DNA fragmentation and assessed the impact of cryoprotectant agents (CPA) with vitrification. A total of 30 normo-ejaculates were prepared by swim up and the motile sperm fraction was divided into four: fresh (control), rapid freezing, and two vitrification groups (a, lacking CPA; b, with CPA). For rapid freezing, a cryovial of sperm suspension was held just above the liquid nitrogen surface, and for vitrification, 30μl suspension was dropped directly into liquid nitrogen. Sperm parameters, including motility, viability and morphology, declined after cryopreservation in both groups. DNA fragmentation was not significantly higher in the vitrification (15.7±4.4%) or rapid freezing (16.6±5.6%) groups when compared with controls (11.6±4.5%). The rates of hyaluronan binding were similar between the control and cryopreserved groups. Moreover, addition of CPA for vitrification had a neutral effect on rates of sperm recovery. In conclusion, vitrification has great potential for human sperm cryopreservation and does not require CPA, with its possible toxicity. However, it is not superior to rapid cryopreservation regarding sperm recovery rate in normozoospermia. Human sperm vitrification is a new cryopreservation method that has been introduced recently. This study compared the effects of rapid freezing with vitrification on rates of sperm parameters, hyaluronan-binding assay and DNA fragmentation after thawing/warming and assessed the impact of cryoprotectant agent (CPA) on vitrification. The study was performed on 30 ejaculates prepared using the swim-up technique. Each motile sperm suspension was divided into four: control (fresh); rapid freezing; and two vitrification groups (a, lacking CPA; b, with CPA). For rapid freezing, a cryovial of sperm suspension was held above the surface of

  10. Sperm DNA Fragmentation Index and Hyaluronan Binding Ability in Men from Infertile Couples and Men with Testicular Germ Cell Tumor.

    Science.gov (United States)

    Marchlewska, Katarzyna; Filipiak, Eliza; Walczak-Jedrzejowska, Renata; Oszukowska, Elzbieta; Sobkiewicz, Slawomir; Wojt, Malgorzata; Chmiel, Jacek; Kula, Krzysztof; Slowikowska-Hilczer, Jolanta

    2016-01-01

    Objective. To investigate sperm DNA fragmentation and sperm functional maturity in men from infertile couples (IC) and men with testicular germ cell tumor (TGCT). Materials and Methods. Semen samples were collected from 312 IC men and 23 men with TGCT before unilateral orchiectomy and oncological treatment. The sperm chromatin dispersion test was performed to determine DNA fragmentation index (DFI) and the ability of sperm to bind with hyaluronan (HA) was assessed. Results. In comparison with the IC men, the men with TGCT had a higher percentage of sperm with fragmented DNA (median 28% versus 21%; p DNA fragmentation and/or sperm immaturity. We therefore recommend sperm banking after unilateral orchiectomy, but before irradiation and chemotherapy; the use of such a deposit appears to be a better strategy to obtain functionally efficient sperms.

  11. Clustered Conserved Cysteines in Hyaluronan Synthase Mediate Cooperative Activation by Mg(2+) Ions and Severe Inhibitory Effects of Divalent Cations.

    Science.gov (United States)

    Tlapak-Simmons, Valarie L; Medina, Andria P; Baggenstoss, Bruce A; Nguyen, Long; Baron, Christina A; Weigel, Paul H

    2011-11-15

    Hyaluronan synthase (HAS) uses UDP-GlcUA and UDP-GlcNAc to make hyaluronan (HA). Streptococcus equisimilis HAS (SeHAS) contains four conserved cysteines clustered near the membrane, and requires phospholipids and Mg(2+) for activity. Activity of membrane-bound or purified enzyme displayed a sigmoidal saturation profile for Mg(2+) with a Hill coefficient of 2. To assess if Cys residues are important for cooperativity we examined the Mg(2+) dependence of mutants with various combinations of Cys-to-Ala mutations. All Cys-mutants lost the cooperative response to Mg(2+). In the presence of Mg(2+), other divalent cations inhibited SeHAS with different potencies (Cu(2+)~Zn(2+) >Co(2+) >Ni(2+) >Mn(2+) >Ba(2+) Sr(2+) Ca(2+)). Some divalent metal ions likely inhibit by displacement of Mg(2+)-UDP-Sugar complexes (e.g. Ca(2+), Sr(2+) and Ba(2+) had apparent Ki values of 2-5 mM). In contrast, Zn(2+) and Cu(2+) inhibited more potently (apparent Ki ≤ 0.2 mM). Inhibition of Cys-null SeHAS by Cu(2+), but not Zn(2+), was greatly attenuated compared to wildtype. Double and triple Cys-mutants showed differing sensitivities to Zn(2+) or Cu(2+). Wildtype SeHAS allowed to make HA prior to exposure to Zn(2+) or Cu(2+) was protected from inhibition, indicating that access of metal ions to sensitive functional groups was hindered in processively acting HA•HAS complexes. We conclude that clustered Cys residues mediate cooperative interactions with Mg(2+) and that transition metal ions inhibit SeHAS very potently by interacting with one or more of these -SH groups.

  12. Increased Hyaluronan Acid Binding Ability of Spermatozoa Indicating a Better Maturity, Morphology, and Higher DNA Integrity After Micronutrient Supplementation

    Directory of Open Access Journals (Sweden)

    Markus Lipovac

    2014-05-01

    Full Text Available Measuring the hyaluronan-binding ability of spermatozoa is useful in predicting the ability of spermatozoa to fertilise oocytes during in vitro fertilisation (IVF. Recent publications discuss an influence of micronutrients on sperm quality. The objective of this paper was to evaluate the effect of a non-prescription nutraceutical containing eight micronutrients on sperm-hyaluronan binding assay (SHBA values among males with idiopathic sub-/infertility, using an open comparative pilot study. The study took place at the Outpatient Fertility Centre IMI, Vienna, Austria, and involved 67 sub-/infertile males. Sub-/infertile males were invited to participate and take two daily capsules of the active compound for a 3-month period between the first and the follow-up semen analysis. Each capsule contained L-carnitine, L-arginine, zinc, vitamin E, glutathione, selenium, coenzyme Q10 (CoQ10, and folic acid (Profertil®. 40 sub-/infertile men receiving no active treatment served as controls; this was measured by change in SHBA after 3 months. It was found that SHBA values significantly increased after 3 months of treatment with the active compound, from a median baseline value of 56.0% to 74% (p<0.05. This represented a 19.7% increase compared to baseline, which was significantly higher than the 2.1% decrease observed in the control group. The rate of subjects displaying an increase in SHBA values after 3 months was significantly higher in the active group (74.6% versus 30.0%, p=0.0001, which showed that sub-/infertile men treated with the active micronutrient compound displayed increased SHBA ability. However, more research is necessary to get detailed information on this specific subject.

  13. 基质细胞衍生因子-1α和白细胞介素-1β诱导淋巴管内皮表型的作用%Effect of stromal cell derived factor-1αand interleukin-1βon inducing vascular endothelial cells expressing lymphatic phenotype

    Institute of Scientific and Technical Information of China (English)

    索宁; 王雪颖; 杨春林; 周辉; 李菲; 张宗璞; 万芳竹; 田铧

    2014-01-01

    目的:探讨基质细胞衍生因子-1α( SDF-1α)及白细胞介素-1β( IL-1β)诱导内皮细胞表达淋巴管表型的作用。方法 SDF-1α和IL-1β分别诱导内皮细胞株CRL-1730,用Real-time PCR、Western blotting 及免疫细胞化学等方法检测其内皮及淋巴管标志物,的表达情况。结果 SDF-1α诱导培养之后,CRL-1730细胞株的内皮细胞标志物血管性血友病因子(vWF)、血管内皮钙黏蛋白(VE-cadherin)、血管内皮生长因子受体(VEGFR)2随其浓度增高而表达降低,淋巴管标志物平足蛋白( podoplanin )、同源异形盒蛋白-1( Prox-1)和淋巴管内皮透明质酸受体-1(LYVE-1)随其浓度增高而表达增高。 IL-1β诱导之后,CRL-1730细胞株的vWF、VEGFR2和podoplanin、prox-1、LYVE-1的变化趋势同SDF-1α,而VE-cadherin的表达量基本不变。结论 SDF-1α和IL-1β都能够诱导血管内皮细胞表达淋巴管标志物。%Objective To investigate the effect of stromal cell-derived factor-1α( SDF-1α) and interleukin ( IL-1β) on inducing vascular endothelial cells to express lymphatic phenotype .Methods The CRL-1730 cell line was cultured and treated with SDF-1αor IL-1β.The expression of endothelial cell markers and lymphatic endothelial cell markers were investigated with Real-time PCR, Western blotting and immunocytochemistry .Results In CRL-1730 cell line, endothelial cell markers such as voln willebrand factor ( vWF ) , VE-cadherin , vascular endothelial growth factor receptor(VEGFR)2, were dose dependently down-regulated after SDF-1αstimulation, while lymphatic phenotypes such as Prox-1, podoplanin and lymphatic vessel endothelial hyaluronan receptor-1(LYVE-1), were dose-dependently up-regulated after SDF-1αstimulation.The changes of vWF, VEGFR2 and podoplanin, Prox-1, LYVE-1 expression after IL-1βstimulation was similar to that after SDF-1αwhile expression of VE-cadherin changed slightly .Conclusion SDF-1αand IL-1

  14. Genetic Association and Gene-gene interaction of HAS2, HABP1 and HYAL3 Implicate Hyaluronan Metabolic Genes in Glaucomatous Neurodegeneration

    Directory of Open Access Journals (Sweden)

    Kaustuv Basu

    2012-01-01

    Full Text Available Hyaluronan (HA plays a significant role in maintaining aqueous humor outflow in trabecular meshwork, the primary ocular tissue involved in glaucoma. We examined potential association of the single nucleotide polymorphisms (SNPs of the HA synthesizing gene – hyaluronan synthase 2 (HAS2, hyaluronan binding protein 1 (HABP1 and HA catabolic gene hyaluronidase 3 (HYAL3 in the primary open angle glaucoma (POAG patients in the Indian population. Thirteen tagged SNPs (6 for HAS2, 3 for HABP1 and 4 for HYAL3 were genotyped in 116 high tension (HTG, 321 non-high tension glaucoma (NHTG samples and 96 unrelated, age-matched, glaucoma-negative, control samples. Allelic and genotypic association were analyzed by PLINK v1.04; haplotypes were identified using PHASE v2.1 and gene-gene interaction was analyzed using multifactor dimensionality reduction (MDR v2.0. An allelic association (rs6651224; p = 0.03; OR: 0.49; 95% CI: 0.25–0.94 was observed at the second intron (C>G of HAS2 both for NHTG and HTG. rs1057308 revealed a genotypic association (p = 0.03 at the 5’ UTR of HAS2 with only HTG. TCT haplotype (rs1805429 – rs2472614 – rs8072363 in HABP1 and TTAG and TTGA (rs2285044 – rs3774753 – rs1310073 – rs1076872 in HYAL3 were found to be significantly high (p < 0.05 both for HTG and NHTG compared to controls. Gene-gene interaction revealed HABP1 predominantly interacts with HAS2 in HTG while it associates with both HYAL3 and HAS2 in NHTG. This is the first genetic evidence, albeit from a smaller study, that the natural polymorphisms in the genes involved in hyaluronan metabolism are potentially involved in glaucomatous neurodegeneration.

  15. Sevoflurane mitigates shedding of hyaluronan from the coronary endothelium, also during ischemia/reperfusion: an ex vivo animal study

    Directory of Open Access Journals (Sweden)

    Chen C

    2016-04-01

    Full Text Available Congcong Chen,1,3 Daniel Chappell,2,3 Thorsten Annecke,2,3 Peter Conzen,2 Matthias Jacob,2,3 Ulrich Welsch,4 Bernhard Zwissler,2 Bernhard F Becker3 1Department of Anesthesiology, Second Affiliated Hospital of Zhejiang University, Hangzhou, People's Republic of China; 2Clinic of Anesthesiology, Ludwig-Maximilians-University, Munich, Germany; 3Walter-Brendel-Centre of Experimental Medicine, Ludwig-Maximilians-University, Munich, Germany; 4Institute of Anatomy, Ludwig-Maximilians-University, Munich, Germany Abstract: Glycosaminoglycan hyaluronan (HA, a major constituent of the endothelial glycocalyx, helps to maintain vascular integrity. Preconditioning the heart with volatile anesthetic agents protects against ischemia/reperfusion injury. We investigated a possible protective effect of sevoflurane on the glycocalyx, especially on HA. The effect of pre-ischemic treatment with sevoflurane (15 minutes at 2% vol/vol gas on shedding of HA was evaluated in 28 isolated, beating guinea pig hearts, subjected to warm ischemia (20 minutes at 37°C followed by reperfusion (40 minutes, half with and half without preconditioning by sevoflurane. HA concentration was measured in the coronary effluent. Over the last 20 minutes of reperfusion hydroxyethyl starch (1 g% was continuously infused and the epicardial transudate collected over the last 5 minutes for measuring the colloid extravasation. Additional hearts were fixed by perfusion after the end of reperfusion for immunohistology and electron microscopy. Sevoflurane did not significantly affect post-ischemic oxidative stress, but strongly inhibited shedding of HA during the whole period, surprisingly even prior to ischemia. Immunohistology demonstrated that heparan sulfates and SDC1 of the glycocalyx were also preserved by sevoflurane. Electron microscopy revealed shedding of glycocalyx caused by ischemia and a mostly intact glycocalyx in hearts exposed to sevoflurane. Coronary vascular permeability of the

  16. Normal and shear interactions between hyaluronan-aggrecan complexes mimicking possible boundary lubricants in articular cartilage in synovial joints.

    Science.gov (United States)

    Seror, Jasmine; Merkher, Yulia; Kampf, Nir; Collinson, Lisa; Day, Anthony J; Maroudas, Alice; Klein, Jacob

    2012-11-12

    Using a surface force balance, normal and shear interactions have been measured between two atomically smooth surfaces coated with hyaluronan (HA), and with HA/aggrecan (Agg) complexes stabilized by cartilage link protein (LP). Such HA/Agg/LP complexes are the most abundant mobile macromolecular species permeating articular cartilage in synovial joints and have been conjectured to be present as boundary lubricants at its surface. The aim of the present study is to gain insight into the extremely efficient lubrication when two cartilage surfaces slide past each other in healthy joints, and in particular to elucidate the possible role in this of the HA/Agg/LP complexes. Within the range of our parameters, our results reveal that the HA/Agg/LP macromolecular surface complexes are much better boundary lubricants than HA alone, likely because of the higher level of hydration, due to the higher charge density, of the HA/Agg/LP layers with respect to the HA alone. However, the friction coefficients (μ) associated with the mutual interactions and sliding of opposing HA/Agg/LP layers (μ ≈ 0.01 up to pressure P of ca. 12 atm, increasing sharply at higher P) suggest that such complexes by themselves cannot account for the remarkable boundary lubrication observed in mammalian joints (up to P > 50 atm).

  17. Fabrication of tubular tissue constructs by centrifugal casting of cells suspended in an in situ crosslinkable hyaluronan-gelatin hydrogel.

    Science.gov (United States)

    Mironov, Vladimir; Kasyanov, Vladimir; Zheng Shu, Xiao; Eisenberg, Carol; Eisenberg, Leonard; Gonda, Steve; Trusk, Thomas; Markwald, Roger R; Prestwich, Glenn D

    2005-12-01

    Achieving the optimal cell density and desired cell distribution in scaffolds is a major goal of cell seeding technologies in tissue engineering. In order to reach this goal, a novel centrifugal casting technology was developed using in situ crosslinkable hyaluronan-based (HA) synthetic extracellular matrix (sECM). Living cells were suspended in a viscous solution of thiol-modified HA and thiol-modified gelatin, a polyethyleneglycol diacrylate crosslinker was added, and a hydrogel was formed during rotation. The tubular tissue constructs consisting of a densely packed cell layer were fabricated with the rotation device operating at 2000 rpm for 10 min. The majority of cells suspended in the HA mixture before rotation were located inside the layer after centrifugal casting. Cells survived the effect of the centrifugal forces experienced under the rotational regime employed. The volume cell density (65.6%) approached the maximal possible volume density based on theoretical sphere packing models. Thus, centrifugal casting allows the fabrication of tubular constructs with the desired redistribution, composition and thickness of cell layers that makes the maximum efficient use of available cells. Centrifugal casting in this sECM would enable rapid fabrication of tissue-engineered vascular grafts, as well as other tubular and planar tissue-engineered constructs.

  18. Architectural organization and functional features of early endothelial progenitor cells cultured in a hyaluronan-based polymer scaffold.

    Science.gov (United States)

    Pasquinelli, Gianandrea; Vinci, Maria Cristina; Gamberini, Chiara; Orrico, Catia; Foroni, Laura; Guarnieri, Carlo; Parenti, Astrid; Gargiulo, Mauro; Ledda, Fabrizio; Caldarera, Claudio Marcello; Muscari, Claudio

    2009-09-01

    Neovascularization can be improved using polymer scaffolds supporting endothelial progenitor cells (EPCs). The aim of the present study was to investigate whether human early EPCs (eEPCs) could be efficiently cultured in a hyaluronan-based non-woven mesh (HYAFF-11). eEPCs were seeded on HYAFF-11 at the density of 1 x 10(6)/cm(2) and cultured with endothelial differentiating factors for 3 weeks. After 24 h, nearly 90% of EPCs were adherent. Cell viability, evaluated by methyltetrazolium test, was greater in HYAFF-11 than on the most commonly used fibronectin-coated dishes, even if a progressive decline in viability was observed starting from approximately the second week of culture. eEPCs easily migrated to and aggregated on the scaffold. Evidence of active protein synthesis and features of endothelial differentiation, including cellular transcytotic channels and micropinocytotic vesicles, was revealed using electron microscopy, immunofluorescence, and reverse transcriptase polymerase chain reaction analysis. eEPCs cultured in the scaffold also showed a certain angiogenic activity, as demonstrated by hepatocyte growth factor transcription and vascular endothelial growth factor secretion. In conclusion, eEPCs can migrate and adhere inside HYAFF-11, maintain their pre-endothelial phenotype, and express angiogenic factors, especially within the first week of growth. These results indicate that non-woven HYAFF-11 could be a promising candidate as a vehicle for eEPCs for regenerative medicine applications.

  19. Over expression of hyaluronan promotes progression of HCC via CD44-mediated pyruvate kinase M2 nuclear translocation

    Science.gov (United States)

    Li, Jing-Huan; Wang, Ying-Cong; Qin, Cheng-Dong; Yao, Rong-Rong; Zhang, Rui; Wang, Yan; Xie, Xiao-Ying; Zhang, Lan; Wang, Yan-Hong; Ren, Zheng-Gang

    2016-01-01

    Hyaluronan is expressed in hepatocellular carcinoma (HCC) as HCC generally arises from a cirrhotic liver in which excessive production and accumulation of HA leads to developing cirrhosis. Though it has been suggested HA is involved in progression of HCC, the mechanisms underlying the connection between HA and HCC progression are unclear. Since increased aerobic glycolysis is a metabolic trait of malignant cells and HA-CD44 can modulate glucose metabolism, we aim to investigate the roles of PKM2, a key enzyme in glucose metabolism, in the HA-CD44 axis facilitated the progress of HCC. We shown PKM2 was required for HA-promoted HCC progression, which was not modulated by PKM2 kinase activity but by nuclear translocation of PKM2. PKM2 translocation was Erk (Thr202/Tyr204) phosphorylation dependent, which functioned at the downstream of HA-CD44 binding. Furthermore, elevated HA expression significantly correlated with PKM2 nuclear location and was an independent factors predicting poor HCC prognosis. In conclusions PKM2 nuclear translocation is required for mediating the described HA biological effects on HCC progression and our results imply that inhibition of HA may have therapeutic value in treating HCC. PMID:27186420

  20. Agarose and Polyacrylamide Gel Electrophoresis Methods for Molecular Mass Analysis of 5–500 kDa Hyaluronan

    Science.gov (United States)

    Bhilocha, Shardul; Amin, Ripal; Pandya, Monika; Yuan, Han; Tank, Mihir; LoBello, Jaclyn; Shytuhina, Anastasia; Wang, Wenlan; Wisniewski, Hans-Georg; de la Motte, Carol; Cowman, Mary K.

    2011-01-01

    Agarose and polyacrylamide gel electrophoresis systems for the molecular mass-dependent separation of hyaluronan (HA) in the size range of approximately 5–500 kDa have been investigated. For agarose-based systems, the suitability of different agarose types, agarose concentrations, and buffers systems were determined. Using chemoenzymatically synthesized HA standards of low polydispersity, the molecular mass range was determined for each gel composition, over which the relationship between HA mobility and logarithm of the molecular mass was linear. Excellent linear calibration was obtained for HA molecular mass as low as approximately 9 kDa in agarose gels. For higher resolution separation, and for extension to molecular masses as low as approximately 5 kDa, gradient polyacrylamide gels were superior. Densitometric scanning of stained gels allowed analysis of the range of molecular masses present in a sample, and calculation of weight-average and number-average values. The methods were validated for polydisperse HA samples with viscosity-average molecular masses of 112, 59, 37, and 22 kDa, at sample loads of 0.5 µg (for polyacrylamide) to 2.5 µg (for agarose). Use of the methods for electrophoretic mobility shift assays was demonstrated for binding of the HA-binding region of aggrecan (recombinant human aggrecan G1-IGD-G2 domains) to a 150 kDa HA standard. PMID:21684248

  1. Force spectroscopy of hyaluronan by atomic force microscopy: from hydrogen-bonded networks toward single-chain behavior.

    Science.gov (United States)

    Giannotti, Marina I; Rinaudo, Marguerite; Vancso, G Julius

    2007-09-01

    The conformational behavior of hyaluronan (HA) polysaccharide chains in aqueous NaCl solution was characterized directly at the single-molecule level. This communication reports on one of the first single-chain atomic force microscopy (AFM) experiments performed at variable temperatures, investigating the influence of the temperature on the stability of the HA single-chain conformation. Through AFM single-molecule force spectroscopy, the temperature destabilization of a local structure was proven. This structure involved a hydrogen-bonded network along the polymeric chain, with hydrogen bonds between the polar groups of HA and possibly water, and a change from a nonrandom coil to a random coil behavior was observed when increasing the temperature from 29 +/- 1 to 46 +/- 1 degrees C. As a result of the applied force, this superstructure was found to break progressively at room temperature. The use of a hydrogen-bonding breaker solvent demonstrated the hydrogen-bonded water-bridged nature of the network structure of HA single chains in aqueous NaCl solution.

  2. Tissue hyaluronan expression, as reflected in the sputum of lung cancer patients, is an indicator of malignancy

    Energy Technology Data Exchange (ETDEWEB)

    Rangel, M.P.; Sá, V.K. de; Martins, V. [Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Martins, J.R.M. [Disciplina de Biologia Molecular, Departamento de Bioquímica, Faculdade de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Disciplina de Endocrinologia e Metabolismo, Laboratório de Endocrinologia Molecular e Translacional-LEMT, Departamento de Medicina, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Parra, E.R. [Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Mendes, A. [Disciplina de Biologia Molecular, Departamento de Bioquímica, Faculdade de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Andrade, P.C. [Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Reis, R.M. [Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga (Portugal); ICVS/3B' s - PT Government Associate Laboratory, Guimarães (Portugal); Centro de Pesquisa em Oncologia Molecular, Hospital de Câncer de Barretos, Fundação Pio XII, Barretos, SP (Brazil); Longatto-Filho, A. [Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga (Portugal); ICVS/3B' s - PT Government Associate Laboratory, Guimarães (Portugal); Laboratório de Investigação Médica (LIM 14), Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Centro de Pesquisa em Oncologia Molecular, Hospital de Câncer de Barretos, Fundação Pio XII, Barretos, SP (Brazil); Oliveira, C.Z. [Centro de Pesquisa em Oncologia Molecular, Hospital de Câncer de Barretos, Fundação Pio XII, Barretos, SP (Brazil); Takagaki, T. [Divisão de Pneumologia, Instituto do Coração, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil); Carraro, D.M. [Centro Internacional de Pesquisa/CIPE, AC Camargo Cancer Center, São Paulo, SP (Brazil); Nader, H.B. [Disciplina de Biologia Molecular, Departamento de Bioquímica, Faculdade de Medicina, Universidade Federal de São Paulo, São Paulo, SP (Brazil); Capelozzi, V.L. [Departamento de Patologia, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP (Brazil)

    2015-05-08

    Hyaluronan (HA) shows promise for detecting cancerous change in pleural effusion and urine. However, there is uncertainty about the localization of HA in tumor tissue and its relationship with different histological types and other components of the extracellular matrix, such as angiogenesis. We evaluated the association between HA and degree of malignancy through expression in lung tumor tissue and sputum. Tumoral tissue had significantly increased HA compared to normal tissue. Strong HA staining intensity associated with cancer cells was significant in squamous cell carcinoma compared to adenocarcinoma and large cell carcinoma. A significant direct association was found between tumors with a high percentage of HA and MVD (microvessel density) in tumoral stroma. Similarly significant was the direct association between N1 tumors and high levels of HA in cancer cells. Cox multivariate analysis showed significant association between better survival and low HA. HA increased in sputum from lung cancer patients compared to cancer-free and healthy volunteers and a significant correlation was found between HA in sputum and HA in cancer tissue. Localization of HA in tumor tissue was related to malignancy and reflected in sputum, making this an emerging factor for an important diagnostic procedure in patients suspected to have lung cancer. Further study in additional patients in a randomized prospective trial is required to finalize these results and to validate our quantitative assessment of HA, as well as to couple it to gold standard sputum cytology.

  3. Sperm DNA Fragmentation Index and Hyaluronan Binding Ability in Men from Infertile Couples and Men with Testicular Germ Cell Tumor

    Directory of Open Access Journals (Sweden)

    Katarzyna Marchlewska

    2016-01-01

    Full Text Available Objective. To investigate sperm DNA fragmentation and sperm functional maturity in men from infertile couples (IC and men with testicular germ cell tumor (TGCT. Materials and Methods. Semen samples were collected from 312 IC men and 23 men with TGCT before unilateral orchiectomy and oncological treatment. The sperm chromatin dispersion test was performed to determine DNA fragmentation index (DFI and the ability of sperm to bind with hyaluronan (HA was assessed. Results. In comparison with the IC men, the men with TGCT had a higher percentage of sperm with fragmented DNA (median 28% versus 21%; p<0.01 and a lower percentage of HA-bound sperm (24% versus 66%; p<0.001. Normal results of both analyses were observed in 24% of IC men and 4% of men with TGCT. Negative Spearman’s correlations were found between DFI and the percentage of HA-bound sperm in the whole group and in IC subjects and those with TGCT analyzed separately. Conclusions. Approximately 76% of IC men and 96% with TGCT awaiting orchiectomy demonstrated DNA fragmentation and/or sperm immaturity. We therefore recommend sperm banking after unilateral orchiectomy, but before irradiation and chemotherapy; the use of such a deposit appears to be a better strategy to obtain functionally efficient sperms.

  4. Low- and high-resolution nuclear magnetic resonance (NMR) characterisation of hyaluronan-based native and sulfated hydrogels.

    Science.gov (United States)

    Barbucci, Rolando; Leone, Gemma; Chiumiento, Antonio; Di Cocco, Maria Enrica; D'Orazio, Giovanni; Gianferri, Raffaella; Delfini, Maurizio

    2006-08-14

    Hyaluronan-based hydrogels were synthesised using different crosslinking agents, such as 1,3-diaminopropane (1,3-DAP) and 1,6-diaminohexane (1,6-DAE). The hydrogels were sulfated to provide materials (Hyal-1,3-DAP, Hyal-1,6-DAE, HyalS-1,3-DAP and HyalS-1,6-DAE) that were characterised by both high- and low-resolution nuclear magnetic resonance (NMR) spectroscopy. The (13)C NMR spectra of the materials were analysed to identify, characterise and study the crosslinking degree of the hydrogels. The crosslinking degree was also determined by potentiometric titration and the effectiveness of the two techniques was compared. Measurements of longitudinal relaxation times (spin-lattice) and of NOE enhancement were used to study the mobility of the hydrogels. Low-resolution NMR studies allowed the determination of the water transport properties in the hydrogels. In addition, the swelling degree for the various hydrogels was calculated as a function of the longitudinal and transversal relaxation times of the water molecules. Lastly, the self-diffusion coefficients of the water in interaction with the four polysaccharides were measured by the pulsed field gradient spin echo (PFGSE) sequence.

  5. Effect of Hyaluronan on Developmental Competence and Quality of Oocytes and Obtained Blastocysts from In Vitro Maturation of Bovine Oocytes

    Directory of Open Access Journals (Sweden)

    Jolanta Opiela

    2014-01-01

    Full Text Available The objective of the present study was to evaluate the effect of hyaluronan (HA during IVM on meiotic maturation, embryonic development, and the quality of oocytes, granulosa cells (GC, and obtained blastocysts. COCs were matured in vitro in control medium and medium with additional 0.035% or 0.07% of exogenous HA. The meiotic maturity did not differ between the analysed groups. The best rate and the highest quality of obtained blastocysts were observed when 0.07% HA was used. A highly significant difference (P<0.001 was noted in the mean number of apoptotic nuclei per blastocyst and in the DCI between the 0.07% HA and the control blastocysts (P<0.01. Our results suggest that addition of 0.035% HA and 0.07% HA to oocyte maturation media does not affect oocyte nuclear maturation and DNA fragmentation. However, the addition of 0.07% HA during IVM decreases the level of blastocysts DNA fragmentation. Finally, our results suggest that it may be risky to increase the HA concentration during IVM above 0.07% as we found significantly higher Bax mRNA expression levels in GC cultured with 0.07% HA. The final concentration of HA being supplemented to oocyte maturation media is critical for the success of the IVP procedure.

  6. Improvement of the Digestibility of Sulfated Hyaluronans by Bovine Testicular Hyaluronidase: A UV Spectroscopic and Mass Spectrometric Study

    Directory of Open Access Journals (Sweden)

    Katharina Lemmnitzer

    2014-01-01

    Full Text Available Glycosaminoglycans (GAGs such as hyaluronan (HA and chondroitin sulfate (CS are important, natural polysaccharides which occur in biological (connective tissues and have various biotechnological and medical applications. Additionally, there is increasing evidence that chemically (oversulfated GAGs possess promising properties and are useful as implant coatings. Unfortunately, a detailed characterization of these GAGs is challenging: although mass spectrometry (MS is one of the most powerful tools to elucidate the structures of (polysaccharides, MS is not applicable to high mass polysaccharides, but characteristic oligosaccharides are needed. These oligosaccharides are normally generated by enzymatic digestion. However, chemically modified (particularly sulfated GAGs are extremely refractive to enzymatic digestion. This study focuses on the investigation of the digestibility of GAGs with different degrees of sulfation by bovine testicular hyaluronidase (BTH. It will be shown by using an adapted spectrophotometric assay that all investigated GAGs can be basically digested if the reaction conditions are carefully adjusted. However, the oligosaccharide yield correlates reciprocally with the number of sulfate residues per polymer repeating unit. Finally, matrix-laser desorption and ionization (MALDI MS will be used to study the released oligosaccharides and their sulfation patterns.

  7. Chitin-Hyaluronan Nanoparticles: A Multifunctional Carrier to Deliver Anti-Aging Active Ingredients through the Skin

    Directory of Open Access Journals (Sweden)

    Pierfrancesco Morganti

    2014-07-01

    Full Text Available The paper describes the process to produce Chitin Nanofibril-Hyaluronan nanoparticles (CN-HA, showing their ability to easily load active ingredients, facilitate penetration through the skin layers, and increase their effectiveness and safety as an anti-aging agent. Size and characterization of CN-HA nanoparticles were determined by Scanning Electron Microscopy (SEM and Zetasizer, while encapsulation efficiency and loading capacity of the entrapped ingredients were controlled by chromatographic and spectrophotometric methods. Safeness was evidenced on fibroblasts and keratinocytes culture viability by the MTT (Methylthiazol assay; anti-aging activity was evaluated in vitro measuring antioxidant capacity, anti-collagenase activity, and metalloproteinase and pro-inflammatory release; efficacy was shown in vivo by a double-blind vehicle-controlled study for 60 days on 60 women affected by photo-aging. In addition, the CN-HA nanoparticles have shown interesting possibility to be used as active ingredients, for designing and making advanced medication by the electrospinning technology, as well as to produce transparent films for food packaging, by the casting method, and can be used also in their dry form as tissues or films without adding preservatives. These unusual CN-HA nanoparticles obtained from the use of raw materials of waste origin may offer an unprecedented occasion for making innovative products, ameliorating the quality of life, reducing pollution and safeguarding the environment’s integrity.

  8. Molecular cloning and tissue distribution of hyaluronan binding protein 2 (HABP2) in red sea bream Pagrus major.

    Science.gov (United States)

    Yoshida, Asami; Wang, Yajun; Bae, Inwoo; Cao, Min-Jie; Osatomi, Kiyoshi; Hara, Kenji

    2013-08-01

    Previously we have isolated a novel gelatinolytic serine proteinase, named G1, from the muscle and the plasma of red sea bream. In order to clarify the structure and function of G1, we cloned the full-length cDNA of G1 from the hepatopancreas of red sea bream. G1 cDNA encoded 633 amino acids with a secretory signal sequence at N-terminus, three epidermal growth factor-like domains, a kringle domain, and a trypsin-like serine protease domain. The active site residues of a serine proteinase were conserved in the serine protease domain of G1. The tissue distributions of the mRNA and gelatinolytic activity of G1 were investigated using RT-PCR and gelatin zymography, respectively. Its activity was detected in various tissues while the mRNA of it was strongly expressed in the hepatopancreas. These results suggest that G1 is synthesized in hepatopancreas and carried to the muscle, kidney, heart and ovary via the bloodstream in the red sea bream. The enzyme has a similar domain structure and tissue distribution to those of human hyaluronan binding protein 2 (HABP2) engaged in the extracellular matrix (ECM) turnover. Thus, it is suggested that G1 is identified as HABP2 and is possibly involved in ECM proteolysis of red sea bream.

  9. Variation in hyaluronan-binding protein 2 (HABP2) promoter region is associated with unexplained female infertility.

    Science.gov (United States)

    Altmäe, Signe; Kallak, Theodora Kunovac; Fridén, Barbo; Stavreus-Evers, Anneli

    2011-05-01

    We set up to analyze polymorphisms in hyaluronan-binding protein 2 (HABP2) gene in healthy fertile women (n = 158) and in women with unexplained infertility (n = 116) and to investigate the potential role of HABP2 in receptive endometrium. Minor rs1157916 A and the major rs2240879 A alleles together with AA genotypes were significantly less frequent in infertile women than in controls. Immunohistochemistry analysis of endometrial HABP2 expression at the time of implantation identified significantly lower HABP2 protein level in infertile women in stroma and vessels than in fertile women. Migration assay analysis of cultured trophoblast and endothelial cells toward HABP2 protein referred to the function of HABP2 in endometrial endothelial cells. In conclusion, our results indicate that polymorphisms in the regulatory region of HABP2 gene could influence gene expression levels in the receptive endometrium and could thereby be one reason for infertility complications in women with unexplained infertility. Additionally, HABP2 protein involvement in endometrial angiogenesis is proposed.

  10. Terminal sialic acids on CD44 N-glycans can block hyaluronan binding by forming competing intramolecular contacts with arginine sidechains

    Science.gov (United States)

    Faller, Christina E.; Guvench, Olgun

    2014-01-01

    Specific sugar residues and their linkages form the basis of molecular recognition for interactions of glycoproteins with other biomolecules. Seemingly small changes, like the addition of a single monosaccharide in the covalently attached glycan component of glycoproteins, can greatly affect these interactions. For instance, the sialic acid capping of glycans affects protein-ligand binding involved in cell-cell and cell-matrix interactions. CD44 is a single-pass transmembrane glycoprotein whose binding with its carbohydrate ligand hyaluronan (HA), an extracellular matrix component, mediates processes such as leukocyte homing, cell adhesion, and tumor metastasis. This binding is highly regulated by glycosylation of the N-terminal extracellular hyaluronan-binding domain (HABD); specifically, sialic acid capped N-glycans of HABD inhibit ligand binding. However, the molecular mechanism behind this sialic acid mediated regulation has remained unknown. Two of the five N-glycosyation sites of HABD have been previously identified as having the greatest inhibitory effect on HA binding, but only if the glycans contain terminal sialic acid residues. These two sites, Asn25 and Asn120, were chosen for in silico glycosylation in this study. Here, from extensive standard molecular dynamics simulations and biased simulations, we propose a molecular mechanism for this behavior based on spontaneously-formed charge-paired hydrogen bonding interactions between the negatively-charged sialic acid residues and positively-charged Arg sidechains known to be critically important for binding to HA, which itself is negatively charged. Such intramolecular hydrogen bonds would preclude associations critical to hyaluronan binding. This observation suggests how CD44 and related glycoprotein binding is regulated by sialylation as cellular environments fluctuate. PMID:25116630

  11. Increased Hyaluronan Levels in HABP1/p32/gC1qR Overexpressing HepG2 Cells Inhibit Autophagic Vacuolation Regulating Tumor Potency

    Science.gov (United States)

    Saha, Paramita; Ghosh, Ilora; Datta, Kasturi

    2014-01-01

    Tumor growth and development is influenced by its microenvironment. A major extracellular matrix molecule involved in cancer progression is hyaluronan (HA). Hyaluronan and expression of a number of hyaladherin family proteins are dramatically increased in many cancer malignancies. One such hyaladherin, hyaluronan-binding protein 1 (HABP1/p32/gC1qR) has been considered to be a biomarker for tumor progression. Interestingly, overexpression of HABP1 in fibroblast has been shown to increase autophagy via generation of excess reactive oxygen species (ROS) and depletion of HA leading to apoptosis. Cancerous cells are often found to exhibit decreased rate of proteolysis/autophagy in comparison to their normal counterparts. To determine if HABP1 levels alter tumorigenicity of cancerous cells, HepR21, the stable transfectant overexpressing HABP1 in HepG2 cell line was derived. HepR21 has been shown to have increased proliferation rate than HepG2, intracellular HA cable formation and enhanced tumor potency without any significant alteration of intracellular ROS. In this paper we have observed that HepR21 cells containing higher endogenous HA levels, have downregulated expression of the autophagic marker, MAP-LC3, consistent with unaltered levels of endogenous ROS. In fact, HepR21 cells seem to have significant resistance to exogenous ROS stimuli and glutathione depletion. HepR21 cells were also found to be more resilient to nutrient starvation in comparison to its parent cell line. Decline in intracellular HA levels and HA cables in HepR21 cells upon treatment with HAS inhibitor (4-MU), induced a surge in ROS levels leading to increased expression of MAP-LC3 and tumor suppressors Beclin 1 and PTEN. This suggests the importance of HABP1 induced HA cable formation in enhancing tumor potency by maintaining the oxidant levels and subsequent autophagic vacuolation. PMID:25061661

  12. Eco-friendly microwave-assisted protocol to prepare hyaluronan-fatty acid conjugates and to induce their self-assembly process.

    Science.gov (United States)

    Calce, Enrica; Mercurio, Flavia Anna; Leone, Marilisa; Saviano, Michele; De Luca, Stefania

    2016-06-05

    An environmentally sustainable and energy-efficient synthetic process has been developed to prepare hyaluronan-based nano-sized material. It consists in a microwave-promoted acylation of the hydroxyl function of the polysaccharide with natural fatty acids, performed under solvent-free conditions. The efficient interaction of the solid reagents with the MW radiation accounts for the obtained high yielded products. The self-assembly process of the obtained compounds very fast occurred in an aqueous medium under MW-radiation, thus allowing the development of a green protocol for the nano-particles preparation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Rheology and Confocal Reflectance Microscopy as Probes of Mechanical Properties and Structure during Collagen and Collagen/Hyaluronan Self-Assembly

    OpenAIRE

    Yang, Ya-Li; Kaufman, Laura J.

    2009-01-01

    In this work, the gelation of three-dimensional collagen and collagen/hyaluronan (HA) composites is studied by time sweep rheology and time lapse confocal reflectance microscopy (CRM). To investigate the complementary nature of these techniques, first collagen gel formation is investigated at concentrations of 0.5, 1.0, and 1.5 mg/mL at 37°C and 32°C. The following parameters are used to describe the self-assembly process in all gels: the crossover time (tc), the slope of the growth phase (kg...

  14. Mapping Sentinel Lymph Node Metastasis by Dual-probe Optical Imaging

    Science.gov (United States)

    Yang, Xiangyu; Wang, Zhe; Zhang, Fuwu; Zhu, Guizhi; Song, Jibin; Teng, Gao-Jun; Niu, Gang; Chen, Xiaoyuan

    2017-01-01

    Purpose: Sentinel lymph node biopsy (SLNB) has emerged as the preferred standard procedure in patients with breast cancer, melanoma and other types of cancer. Herein, we developed a method to intra-operatively map SLNs and differentiate tumor metastases within SLNs at the same time, with the aim to provide more accurate and real-time intraoperative guidance. Experimental Design: Hyaluronic acid (HA), a ligand of lymphatic vessel endothelial hyaluronan receptor (LYVE)-1, is employed as a SLN mapping agent after being conjugated with a near-infrared fluorophore (Cy5.5). Different sized HAs (5, 10 and 20K) were tested in normal mice and mice with localized inflammation to optimize LN retention time and signal to background ratio. Cetuximab, an antibody against epidermal growth factor receptor (EGFR), and trastuzumab, an antibody against human epidermal growth factor receptor 2 (HER2), were labeled with near-infrared fluorophore (IRDye800) for detecting metastatic tumors. LN metastasis model was developed by hock injection of firefly luciferase engineered human head neck squamous carcinoma cancer UM-SCC-22B cells or human ovarian cancer SKOV-3 cells. The metastases within LNs were confirmed by bioluminescence imaging (BLI). IRDye800-Antibodies were intravenously administered 24 h before local administration of Cy5.5-HA. Optical imaging was then performed to identify nodal metastases. Results: Binding of HA with LYVE-1 was confirmed by ELISA and fluorescence staining. HA with a size of 10K was chosen based on the favorable migration and retention profile. After sequential administration of IRDye800-antibodies intravenously and Cy5.5-HA locally to a mouse model with LN metastases and fluorescence optical imaging, partially metastasized LNs were successfully distinguished from un-metastasized LNs and fully tumor occupied LNs, based on the different signal patterns. Conclusions: Fluorophore conjugated HA is a potential lymphatic mapping agent for SLNB. Dual-tracer imaging

  15. Autoimmunity in Graves' ophthalmopathy: the result of an unfortunate marriage between TSH receptors and IGF-1 receptors?

    Science.gov (United States)

    Wiersinga, Wilmar M

    2011-08-01

    The immunopathogenesis of Graves' ophthalmopathy (GO) is still incompletely understood. Attention has shifted from the TSH receptor (TSHR) to the IGF-I receptor (IGF-1R) as a major autoantigen. This review on the pathophysiology of GO focused on orbital fibroblasts and the question whether autoimmunity against TSHR or IGF-1R is primarily involved. Relevant papers on GO were identified by a search on PubMed and scrutiny of their reference lists. In addition, abstracts presented on GO at the 14th International Thyroid Congress in 2010 in Paris, France, were read. Orbital fibroblasts (OF) are recognized as the prime target cells of the autoimmune attack in GO. In early stages OF are undifferentiated with low TSHR expression and are stimulated to produce hyaluronan by cytokines (released by activated infiltrating T cells) and not by Graves' IgG. OF lacking the surface glycoprotein Thy-1 (not present in the muscle compartment) may differentiate into adipocytes, associated with increased TSHR expression. Graves IgG stimulate hyaluronan in differentiated OF mostly via non-cAMP signaling pathways for growth, which can also be activated via TSHR. The existence of IGF-1R stimulating antibodies in serum remains dubious. Autoimmunity against IGF-1R is also observed in rheumatoid arthritis and is not specific for Graves' disease. Expression of IGF-1R on T and B lymphocytes may contribute to autoimmunity against fibroblasts. Autoimmunity against TSHR is most likely initiating the immune response in GO. Autoimmunity against IGF-1R is not specific for Graves' DISEASE but may contribute to ongoing immune reactions.

  16. Antioxidant protects against increases in low molecular weight hyaluronan and inflammation in asphyxiated newborn pigs resuscitated with 100% oxygen.

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    Helene C D Østerholt

    Full Text Available BACKGROUND: Newborn resuscitation with 100% oxygen is associated with oxidative-nitrative stresses and inflammation. The mechanisms are unclear. Hyaluronan (HA is fragmented to low molecular weight (LMW by oxidative-nitrative stresses and can promote inflammation. We examined the effects of 100% oxygen resuscitation and treatment with the antioxidant, N-acetylcysteine (NAC, on lung 3-nitrotyrosine (3-NT, LMW HA, inflammation, TNFα and IL1ß in a newborn pig model of resuscitation. METHODS & PRINCIPAL FINDINGS: Newborn pigs (n = 40 were subjected to severe asphyxia, followed by 30 min ventilation with either 21% or 100% oxygen, and were observed for the subsequent 150 minutes in 21% oxygen. One 100% oxygen group was treated with NAC. Serum, bronchoalveolar lavage (BAL, lung sections, and lung tissue were obtained. Asphyxia resulted in profound hypoxia, hypercarbia and metabolic acidosis. In controls, HA staining was in airway subepithelial matrix and no 3-NT staining was seen. At the end of asphyxia, lavage HA decreased, whereas serum HA increased. At 150 minutes after resuscitation, exposure to 100% oxygen was associated with significantly higher BAL HA, increased 3NT staining, and increased fragmentation of lung HA. Lung neutrophil and macrophage contents, and serum TNFα and IL1ß were higher in animals with LMW than those with HMW HA in the lung. Treatment of 100% oxygen animals with NAC blocked nitrative stress, preserved HMW HA, and decreased inflammation. In vitro, peroxynitrite was able to fragment HA, and macrophages stimulated with LMW HA increased TNFα and IL1ß expression. CONCLUSIONS & SIGNIFICANCE: Compared to 21%, resuscitation with 100% oxygen resulted in increased peroxynitrite, fragmentation of HA, inflammation, as well as TNFα and IL1ß expression. Antioxidant treatment prevented the expression of peroxynitrite, the degradation of HA, and also blocked increases in inflammation and inflammatory cytokines. These findings

  17. Effects of tenoxicam and aspirin on the metabolism of proteoglycans and hyaluronan in normal and osteoarthritic human articular cartilage.

    Science.gov (United States)

    Manicourt, D H; Druetz-Van Egeren, A; Haazen, L; Nagant de Deuxchaisnes, C

    1994-01-01

    1. As nonsteroidal anti-inflammatory drugs may impair the ability of the chondrocyte to repair its damaged extracellular matrix, we explored the changes in the metabolism of newly synthesized proteoglycan (PG) and hyaluronan (HA) molecules produced by tenoxicam and aspirin in human normal cartilage explants and in osteoarthritic (OA) cartilage from age-matched donors. 2. Explants were sampled from the medial femoral condyle and were classified by use of Mankin's histological-histochemical grading system. Cartilage specimens were normal in 10 subjects, exhibited moderate OA (MOA) in 10 and had severe OA (SOA) in 10. 3. Cartilage explants were pulsed with [3H]-glucosamine and chased in the absence and in the presence of either aspirin (190 micrograms ml-1) or tenoxicam (4-16 micrograms ml-1). After papain digestion, the labelled chondroitin sulphate ([3H]-PGs) and HA([3H]-HA) molecules present in the tissue and media were purified by anion-exchange chromatography. 4. In normal cartilage as well as in explants with MOA and SOA aspirin reduced more strongly PG and HA synthesis than the loss of [3H]-HA and [3H]-PGs. 5. In normal cartilage, tenoxicam did not affect PG metabolism whereas it reduced HA synthesis in a dose-dependent manner and did not change or even increased the net loss of [3H]-HA. In contrast, in OA cartilage, tenoxicam produced a stronger reduction in the loss of [3H]-PGs than in PG synthesis and this decrease occurred at lower concentrations in cartilage with SOA (4-8 micrograms ml-1) than in cartilage with MOA (8-16 micrograms ml-1).(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7889262

  18. Radiosensitizing and Hyperthermic Properties of Hyaluronan Conjugated, Dextran-Coated Ferric Oxide Nanoparticles: Implications for Cancer Stem Cell Therapy

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    Ranjeeta Thapa

    2015-01-01

    Full Text Available Cytotoxicity, radiosensitivity, and hyperthermia sensitivity of hyaluronan-mediated dextran-coated super paramagnetic iron oxide nanoparticles (HA-DESPIONs were assessed in CD44-expressing head and neck squamous cell carcinoma (HNSCC cell lines at clinically relevant radiation dose and temperatures. Low-passage HNSCC cells were exposed to HA-DESPIONs and cytotoxicity was assessed using MTT assay. Radiosensitizing properties of graded doses of HA-DESPIONs were assessed in both unsorted and CD44-sorted cells using clonogenic assay in combination with 2 Gy exposure to X-rays. Hyperthermia-induced toxicity was measured at 40°C, 41°C, and 42°C using clonogenic assay. Cell death was assessed 24 hours after treatment using a flow cytometry-based apoptosis analysis. Results showed that HA-DESPIONs were nontoxic at moderate concentrations and did not directly radiosensitize the cell lines. Further, there was no significant difference in the radiosensitivity of CD44high and CD44low cells. However, HA-DESPIONs enhanced the effect of hyperthermia which resulted in reduced cell survival that appeared to be mediated through apoptosis. We demonstrated that HA-DESPIONs are nontoxic and although they do not enhance radiation sensitivity, they did increase the effect of local hyperthermia. These results support further development of drug-attached HA-DESPIONs in combination with radiation for targeting cancer stem cells (CSCs and the development of an alternating magnetic field approach to activate the HA-DESPIONs attached to CSCs.

  19. Transient exposure of pulmonary surfactant to hyaluronan promotes structural and compositional transformations into a highly active state.

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    Lopez-Rodriguez, Elena; Cruz, Antonio; Richter, Ralf P; Taeusch, H William; Pérez-Gil, Jesús

    2013-10-11

    Pulmonary surfactant is a lipid-protein complex that lowers surface tension at the respiratory air-liquid interface, stabilizing the lungs against physical forces tending to collapse alveoli. Dysfunction of surfactant is associated with respiratory pathologies such as acute respiratory distress syndrome or meconium aspiration syndrome where naturally occurring surfactant-inhibitory agents such as serum, meconium, or cholesterol reach the lung. We analyzed the effect of hyaluronan (HA) on the structure and surface behavior of pulmonary surfactant to understand the mechanism for HA-promoted surfactant protection in the presence of inhibitory agents. In particular, we found that HA affects structural properties such as the aggregation state of surfactant membranes and the size, distribution, and order/packing of phase-segregated lipid domains. These effects do not require a direct interaction between surfactant complexes and HA and are accompanied by a compositional reorganization of large surfactant complexes that become enriched with saturated phospholipid species. HA-exposed surfactant reaches very high efficiency in terms of rapid and spontaneous adsorption of surfactant phospholipids at the air-liquid interface and shows significantly improved resistance to inactivation by serum or cholesterol. We propose that physical effects pertaining to the formation of a meshwork of interpenetrating HA polymer chains are responsible for the changes in surfactant structure and composition that enhance surfactant function and, thus, resistance to inactivation. The higher resistance of HA-exposed surfactant to inactivation persists even after removal of the polymer, suggesting that transient exposure of surfactant to polymers like HA could be a promising strategy for the production of more efficient therapeutic surfactant preparations.

  20. Phase I-II clinical trial of hyaluronan-cisplatin nanoconjugate in dogs with naturally occurring malignant tumors.

    Science.gov (United States)

    Cai, Shuang; Zhang, Ti; Forrest, W C; Yang, Qiuhong; Groer, Chad; Mohr, Eva; Aires, Daniel J; Axiak-Bechtel, Sandra M; Flesner, Brian K; Henry, Carolyn J; Selting, Kimberly A; Tate, Deborah; Swarz, Jeffrey A; Bryan, Jeffrey N; Forrest, M Laird

    2016-09-01

    OBJECTIVE To conduct a phase I-II clinical trial of hyaluronan-cisplatin nanoconjugate (HA-Pt) in dogs with naturally occurring malignant tumors. ANIMALS 18 healthy rats, 9 healthy mice, and 16 dogs with cancer. PROCEDURES HA-Pt was prepared and tested by inductively coupled plasma mass spectrometry; DNA-platinum adduct formation and antiproliferation effects of cisplatin and HA-Pt were compared in vitro. Effects of cisplatin (IV) and HA-Pt (SC) in rodents were tested by clinicopathologic assays. In the clinical trial, dogs with cancer received 1 to 4 injections of HA-Pt (10 to 30 mg/m(2), intratumoral or peritumoral, q 3 wk). Blood samples were collected for pharmacokinetic analysis; CBC, serum BUN and creatinine concentration measurement, and urinalysis were conducted before and 1 week after each treatment. Some dogs underwent hepatic enzyme testing. Tumors were measured before the first treatment and 3 weeks after each treatment to assess response. RESULTS No adverse drug effects were detected in pretrial assessments in rodents. Seven of 16 dogs completed the study; 3 had complete tumor responses, 3 had stable disease, and 1 had progressive disease. Three of 7 dogs with oral and nasal squamous cell carcinoma (SCC) that completed the study had complete responses. Myelosuppression and cardiotoxicosis were identified in 6 and 2 dogs, respectively; none had nephrotoxicosis. Four of 5 dogs with hepatic enzymes assessed had increased ALT activities, attributed to diaquated cisplatin products in the HA-Pt. Pharmacokinetic data fit a 3-compartment model. CONCLUSIONS AND CLINICAL RELEVANCE HA-Pt treatment resulted in positive tumor responses in some dogs, primarily those with SCC. The adverse effect rate was high. IMPACT FOR HUMAN MEDICINE Oral SCC in dogs has characteristics similar to human head and neck SCC; these results could be useful in developing human treatments.

  1. Preventing effects of joint contracture by high molecular weight hyaluronan injections in a rat immobilized knee model.

    Science.gov (United States)

    Kanazawa, Kenji; Hagiwara, Yoshihiro; Tsuchiya, Masahiro; Yabe, Yutaka; Sonofuchi, Kazuaki; Koide, Masashi; Sekiguchi, Takuya; Itaya, Nobuyuki; Ando, Akira; Saijo, Yoshifumi; Itoi, Eiji

    2015-01-01

    To elucidate preventive effects of high molecular weight hyaluronan (HMWHA) on the joint capsule of immobilized knees in rats. Unilateral knee joints of rats were immobilized with an internal fixator. Either 50 μl of HMWHA (Im-HA group) or 50 μl of saline (control group) was administered intra-articularly once a week after surgery. Sagittal sections were prepared from the medial midcondylar region of the knee joints and assessed by histological, histomorphometric, and immunohistochemical methods. Gene expressions related to inflammation, fibrotic conditions, and hypoxia were evaluated by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Tissue elasticity of the capsule from both groups was examined using a scanning acoustic microscope (SAM). CD68 positive cells decreased in adhesion areas of the synovial membrane after 1 week in both groups. The length of the superficial layer in the synovial membrane of the Im-HA group was significantly longer than those in the control group over a period of 4 to 8 weeks with significantly small numbers of CD68 positive cells. The gene expressions of IL-6, IL-1β, TGF-β, CTGF, COL1a1, COL3a1, SPARC, and HIF1-α were significantly lower in the Im-HA group compared to those in the control group. The sound speed of the anterior and posterior synovial membrane increased significantly (a reduction in elasticity) in the control group compared to those in the Im-HA group during weeks 1 to 4. This study demonstrated that HMWHA injections suppressed inflammatory, fibrotic, and hypoxic conditions observed in the immobilized joint capsule.

  2. Inherited polymorphisms in hyaluronan synthase 1 predict risk of systemic B-cell malignancies but not of breast cancer.

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    Hemalatha Kuppusamy

    Full Text Available Genetic variations in the hyaluronan synthase 1 gene (HAS1 influence HAS1 aberrant splicing. HAS1 is aberrantly spliced in malignant cells from multiple myeloma (MM and Waldenstrom macroglobulinemia (WM, but not in their counterparts from healthy donors. The presence of aberrant HAS1 splice variants predicts for poor survival in multiple myeloma (MM. We evaluated the influence of inherited HAS1 single nucleotide polymorphisms (SNP on the risk of having a systemic B cell malignancy in 1414 individuals compromising 832 patients and 582 healthy controls, including familial analysis of an Icelandic kindred. We sequenced HAS1 gene segments from 181 patients with MM, 98 with monoclonal gammopathy of undetermined significance (MGUS, 72 with Waldenstrom macroglobulinemia (WM, 169 with chronic lymphocytic leukemia (CLL, as well as 34 members of a monoclonal gammopathy-prone Icelandic family, 212 age-matched healthy donors and a case-control cohort of 295 breast cancer patients with 353 healthy controls. Three linked single nucleotide polymorphisms (SNP in HAS1 intron3 are significantly associated with B-cell malignancies (range p = 0.007 to p = 10(-5, but not MGUS or breast cancer, and predict risk in a 34 member Icelandic family (p = 0.005, Odds Ratio = 5.8 (OR, a relatively homogeneous cohort. In contrast, exon3 SNPs were not significantly different among the study groups. Pooled analyses showed a strong association between the linked HAS1 intron3 SNPs and B-cell malignancies (OR = 1.78, but not for sporadic MGUS or for breast cancer (OR<1.0. The minor allele genotypes of HAS1 SNPs are significantly more frequent in MM, WM, CLL and in affected members of a monoclonal gammopathy-prone family than they are in breast cancer, sporadic MGUS or healthy donors. These inherited changes may increase the risk for systemic B-cell malignancies but not for solid tumors.

  3. Development of a complex hydrogel of hyaluronan and PVA embedded with silver nanoparticles and its facile studies on Escherichia coli.

    Science.gov (United States)

    Zhang, Fei; Wu, Juan; Kang, Ding; Zhang, Hongbin

    2013-01-01

    Novel nanocomposite hydrogels composed of hyaluronan (HA), poly(vinyl alcohol) (PVA) and silver nanoparticles were prepared by several cycles of freezing and thawing. The nanocomposite was then characterised using Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), wide-angle X-ray diffraction (XRD) and scanning electron microscopy (SEM). The complex hydrogels consisted of semi-interpenetrating network structures, with PVA microcrystallines as junction zones. By increasing the HA content, the crystallinity and melting temperature of the complex hydrogels decreased, whereas the glass transition temperatures of these materials increased because of the steric hindrance of HA and the occurrence of intermolecular interactions through hydrogen bonding between HA and PVA in the complex hydrogels. Swelling studies showed that in comparison with the swelling properties of the cryogels from PVA alone, those of the complex hydrogels can be significantly improved and presented in a pH-sensitive manner. In addition, silver nanoparticles were synthesised through UV-initiated photoreduction with HA functioning as a reducing agent and stabiliser. The silver nanoparticles were then incorporated in situ into the HA/PVA complex hydrogel matrix. The size and morphology of the as-prepared Ag nanoparticles were investigated through ultraviolet-visible light spectroscopy, transmission electron microscopy, XRD and thermogravimetric analysis. The experimental results indicated that silver nanoparticles 20-50 nm in size were uniformly dispersed in the hydrogel matrix. The antibacterial effects of the HA/PVA/Ag nanocomposite hydrogel against Escherichia coli were evaluated. The results show that this nanocomposite hydrogel possesses high antibacterial property and has a potential application as a wound dressing material.

  4. Cell density-dependent stimulation of PAI-1 and hyaluronan synthesis by TGF-β in orbital fibroblasts.

    Science.gov (United States)

    Galgoczi, Erika; Jeney, Florence; Gazdag, Annamaria; Erdei, Annamaria; Katko, Monika; Nagy, Domonkos M; Ujhelyi, Bernadett; Steiber, Zita; Gyory, Ferenc; Berta, Eszter; Nagy, Endre V

    2016-05-01

    During the course of Graves' orbitopathy (GO), orbital fibroblasts are exposed to factors that lead to proliferation and extracellular matrix (ECM) overproduction. Increased levels of tissue plasminogen activator inhibitor type 1 (PAI-1 (SERPINE1)) might promote the accumulation of ECM components. PAI-1 expression is regulated by cell density and various cytokines and growth factors including transforming growth factorβ(TGF-β). We examined the effects of increasing cell densities and TGF-β on orbital fibroblasts obtained from GO patients and controls. Responses were evaluated by the measurement of proliferation, PAI-1 expression, and ECM production. There was an inverse correlation between cell density and the per cell production of PAI-1. GO orbital, normal orbital, and dermal fibroblasts behaved similarly in this respect. Proliferation rate also declined with increasing cell densities. Hyaluronan (HA) production was constant throughout the cell densities tested in all cell lines. In both GO and normal orbital fibroblasts, but not in dermal fibroblasts, TGF-β stimulated PAI-1 production in a cell density-dependent manner, reaching up to a five-fold increase above baseline. This has been accompanied by increased HA secretion and pericellular HA levels at high cell densities. Increasing cell density is a negative regulator of proliferation and PAI-1 secretion both in normal and GO orbital fibroblasts; these negative regulatory effects are partially reversed in the presence of TGF-β. Cell density-dependent regulation of PAI-1 expression in the orbit, together with the local cytokine environment, may have a regulatory role in the turnover of the orbital ECM and may contribute to the expansion of orbital soft tissue in GO.

  5. Renal intratubular crystals and hyaluronan staining occur in stone formers with bypass surgery but not with idiopathic calcium oxalate stones.

    Science.gov (United States)

    Evan, Andrew P; Coe, Fredric L; Gillen, Daniel; Lingeman, James E; Bledsoe, Sharon; Worcester, Elaine M

    2008-03-01

    Whether idiopathic calcium oxalate (CaOx) stone formers form inner medullary collecting duct (IMCD) crystal deposits bears on pathogenetic mechanisms of stone formation. In prior work, using light and transmission electron microscopy, we have found no IMCD crystal deposits. Here, we searched serial sections of papillary biopsies from a prior study of 15 idiopathic calcium oxalate stone formers, 4 intestinal bypass patients with CaOx stones, and 4 non-stone-forming subjects, and biopsies from an additional hitherto unreported 15 idiopathic calcium oxalate stone formers and 1 bypass patient using polarized light oil immersion optics, for deposits overlooked in our original study. We found no IMCD deposits in any of 1,500 serial sections from the 30 idiopathic calcium oxalate stone formers, nor in 87 additional sections from a frozen idiopathic calcium oxalate stone former biopsy sample processed without exposure to aqueous solutions. Among 4 of the 5 bypass patients but in none of the 30 idiopathic calcium oxalate stone formers or 4 normal stone formers, we found tiny birefringent thin crystalline overlays on scattered IMCD cell membranes. We also found IMCD lumen deposits in two bypass patients that contained mixed birefringent and nonbirefringent crystals, presumably CaOx and apatite. In the bypass patients, we observed focal apical IMCD cell hyaluronan staining, which was absent in idiopathic calcium oxalate stone formers. The absence of any IMCD deposits in 1,500 serial sections of biopsies from 30 idiopathic calcium oxalate stone formers allows us to place the upper limit on the probability of their occurrence at approximately 0.002 and place the lower limit of their size at the resolution of the optics (crystal lesion.

  6. Hyaluronan/Tannic Acid Nanoparticles Via Catechol/Boronate Complexation as a Smart Antibacterial System.

    Science.gov (United States)

    Montanari, Elita; Gennari, Arianna; Pelliccia, Maria; Gourmel, Charlotte; Lallana, Enrique; Matricardi, Pietro; McBain, Andrew J; Tirelli, Nicola

    2016-12-01

    Nanoparticles based on hyaluronic acid (HA) are designed to deliver tannic acid (TA) as an antimicrobial agent. The presence of HA makes these particles potentially useful to target bacteria that colonize cells presenting HA membrane receptors (e.g. CD44), such as macrophages. HA bearing 3-aminophenyl boronic acid groups (HA-APBA) is reacted with TA, yielding nanoparticles with a size that decreases with decreasing HA molecular weight (e.g. 200 nm for 44 kDa, 400 nm for 737 kDa). The boronate esters make the nanoparticles stable at physiological pH, but their hydrolysis in an acidic environment (pH = 5) leads to swelling/solubilization, therefore potentially allowing TA release in endosomal compartments. We have assessed the nanoparticle toxicity profile (on RAW 264.7 macrophages) and their antimicrobial activity (on E. coli and on both methicillin-sensitive and -resistant S. aureus). The antibacterial effect of HA-APBA/TA nanoparticles was significantly higher than that of TA alone, and has very similar activity to TA coformulated with a reducing agent (ascorbic acid), which indicates both the nanoparticles to protect TA catechols from oxidation, and the effective release of TA after nanoparticle internalization. Therefore, there is potential for these nanoparticles to be used in stable, effective, and potentially targetable nanoparticle-based antimicrobial formulations.

  7. Prostaglandin E2 receptor EP4 as the common target on cancer cells and macrophages to abolish angiogenesis, lymphangiogenesis, metastasis, and stem-like cell functions.

    Science.gov (United States)

    Majumder, Mousumi; Xin, Xiping; Liu, Ling; Girish, Gannareddy V; Lala, Peeyush K

    2014-09-01

    We previously established that COX-2 overexpression promotes breast cancer progression and metastasis. As long-term use of COX-2 inhibitors (COX-2i) can promote thrombo-embolic events, we tested an alternative target, prostaglandin E2 receptor EP4 subtype (EP4), downstream of COX-2. Here we used the highly metastatic syngeneic murine C3L5 breast cancer model to test the role of EP4-expressing macrophages in vascular endothelial growth factor (VEGF)-C/D production, angiogenesis, and lymphangiogenesis in situ, the role of EP4 in stem-like cell (SLC) functions of tumor cells, and therapeutic effects of an EP4 antagonist RQ-15986 (EP4A). C3L5 cells expressed all EP receptors, produced VEGF-C/D, and showed high clonogenic tumorsphere forming ability in vitro, functions inhibited with COX-2i or EP4A. Treating murine macrophage RAW 264.7 cell line with COX-2i celecoxib and EP4A significantly reduced VEGF-A/C/D production in vitro, measured with quantitative PCR and Western blots. Orthotopic implants of C3L5 cells in C3H/HeJ mice showed rapid tumor growth, angiogenesis, lymphangiogenesis (CD31/LYVE-1 and CD31/PROX1 immunostaining), and metastasis to lymph nodes and lungs. Tumors revealed high incidence of EP4-expressing, VEGF-C/D producing macrophages identified with dual immunostaining of F4/80 and EP4 or VEGF-C/D. Celecoxib or EP4A therapy at non-toxic doses abrogated tumor growth, lymphangiogenesis, and metastasis to lymph nodes and lungs. Residual tumors in treated mice revealed markedly reduced VEGF-A/C/D and phosphorylated Akt/ERK proteins, VEGF-C/D positive macrophage infiltration, and proliferative/apoptotic cell ratios. Knocking down COX-2 or EP4 in C3L5 cells or treating cells in vitro with celecoxib or EP4A and treating tumor-bearing mice in vivo with the same drug reduced SLC properties of tumor cells including preferential co-expression of COX-2 and SLC markers ALDH1A, CD44, OCT-3/4, β-catenin, and SOX-2. Thus, EP4 is an excellent therapeutic target to block

  8. A prospective randomised controlled clinical trial comparing the efficacy of different molecular weight hyaluronan solutions in the treatment of knee osteoarthritis.

    Science.gov (United States)

    Kotevoglu, Nurdan; Iyibozkurt, Pinar Cakil; Hiz, Ozcan; Toktas, Hasan; Kuran, Banu

    2006-02-01

    Viscosupplementation consists of injecting exagenous hyaluronan (HA) into the synovial joints to restore the normal rheological environment which deteriorates severely in osteoarthritic (OA) joints. Efficacy might be related to the rheological properties and molecular weight (MW) of the hyaluronan preparations. This prospective, controlled, double-blind, randomised clinical trial was aimed at comparing the elastoviscous properties of a high molecular weight viscosupplement, hylan G-F 20, with that of a lower molecular weight hyaluronan product in order to determine the relationship of elastoviscosity to efficacy, alongside placebo, in the treatment of patients with knee OA. The results were analysed as a "completers" analysis with 59 patients. Primary outcome measures included the Western Ontario and Mc Master Universities' Osteoarthritis Index (WOMAC) for pain, stiffness and function scores, and patient and physician global assessments (0-100 scale). For patient (PGA) and physician global assessments (PhGA), the 0-100 scale was used, with 100 being the worst. Follow-up assessments were made at intervals of 1, 3 and 6 months after the first injection. Local adverse events, such as transient pain at the injection site or warm knee lasting for one night, were recorded in two patients (3%). In all groups, the WOMAC pain score exhibited a significant difference from the baseline value; neither treatment group was significantly different from the placebo group, but total pain score was significantly better than baseline for both of the HA groups at the end of 6 months (p < 0.05). Improvement in WOMAC physical function score favoured both sodium hyaluronate and hylan G-F 20 after the first month, and remained significant until the end of 6 months (p < 0.01). In the placebo group, the physical function scores became worse after the end of the 1st month; the scores at the end of 6 months were no different from those at the beginning. The WOMAC stiffness scores of both of

  9. Intra-articular hyaluronan is without clinical effect in knee osteoarthritis: a multicentre, randomised, placebo-controlled, double-blind study of 337 patients followed for 1 year

    DEFF Research Database (Denmark)

    Jørgensen, Anette; Stengaard-Pedersen, Kristian; Simonsen, Lars Ole;

    2010-01-01

    Objective To examine the long-term efficacy and safety of five intra-articular injections with hyaluronan in knee osteoarthritis. Methods A multicentre, randomised, placebo-controlled double-blind study of 337 patients fulfilling the American College of Rheumatology (ACR) criteria for knee...... efficacy parameter. LFI, pain on walking 50 m based on visual analogue scale (VAS pain 50 m), paracetamol consumption, patients' global assessment, Nottingham health profile, joint effusion and number of responders were secondary efficacy parameters. The efficacy parameters were analysed by intention...... to treat (ITT) and per protocol (PP). All adverse events (AE) were recorded as safety parameters. Results Time to recurrence showed no significant treatment effect (ITT analysis, p = 0.26). Change from baseline in LFI and VAS pain 50 m for the ITT population showed no treatment effect. Paracetamol...

  10. Improving post-transfer survival of bovine embryos produced in vitro: actions of insulin-like growth factor-1, colony stimulating factor-2 and hyaluronan.

    Science.gov (United States)

    Block, J; Hansen, P J; Loureiro, B; Bonilla, L

    2011-12-01

    Technologies for in vitro embryo production have the potential to enhance the efficiency of cattle production systems. However, utilization of in vitro-produced embryos for transfer remains limited throughout much of the world. Despite improvements over the past two decades, problems associated with the production of bovine embryos in vitro still exist which limit the widespread commercial application of this technology. In particular, bovine embryos produced in vitro have a reduced capacity to establish and maintain pregnancy as compared with their in vivo-derived counterparts. Embryo competence for survival following transfer is improved by in vivo culture in the sheep oviduct, thus indicating that standard embryo culture conditions are sub-optimal. Therefore, one strategy to improve post-transfer survival is to modify embryo culture media to more closely mimic the in vivo microenvironment. The maternal environment in which the bovine embryo develops in vivo contains various growth factors, cytokines, hormones, and other regulatory molecules. In addition to affecting bovine embryo development in vitro, recent research indicates that embryo competence for survival following transfer can also be improved when such molecules are added to embryo culture medium. Among the specific molecules that can increase post-transfer embryo survival are insulin-like growth factor-1 (IGF-1), colony stimulating factor-2 (CSF-2) and hyaluronan. This paper will review the effects IGF-1, CSF-2 and hyaluronan on post-culture embryo viability and discuss the potential mechanisms through which each of these molecules improves post-transfer survival. Copyright © 2011 Elsevier Inc. All rights reserved.

  11. Interleukin-10-mediated regenerative postnatal tissue repair is dependent on regulation of hyaluronan metabolism via fibroblast-specific STAT3 signaling.

    Science.gov (United States)

    Balaji, Swathi; Wang, Xinyi; King, Alice; Le, Louis D; Bhattacharya, Sukanta S; Moles, Chad M; Butte, Manish J; de Jesus Perez, Vinicio A; Liechty, Kenneth W; Wight, Thomas N; Crombleholme, Timothy M; Bollyky, Paul L; Keswani, Sundeep G

    2017-03-01

    The cytokine IL-10 has potent antifibrotic effects in models of adult fibrosis, but the mechanisms of action are unclear. Here, we report a novel finding that IL-10 triggers a signal transducer and activator of transcription 3 (STAT3)-dependent signaling pathway that regulates hyaluronan (HA) metabolism and drives adult fibroblasts to synthesize an HA-rich pericellular matrix, which mimics the fetal regenerative wound healing phenotype with reduced fibrosis. By using cre-lox-mediated novel, inducible, fibroblast-, keratinocyte-, and wound-specific STAT3-knockdown postnatal mice-plus syngeneic fibroblast cell-transplant models-we demonstrate that the regenerative effects of IL-10 in postnatal wounds are dependent on HA synthesis and fibroblast-specific STAT3-dependent signaling. The importance of IL-10-induced HA synthesis for regenerative wound healing is demonstrated by inhibition of HA synthesis in a murine wound model by administering 4-methylumbelliferone. Although IL-10 and STAT3 signaling were intact, the antifibrotic repair phenotype that is induced by IL-10 overexpression was abrogated in this model. Our data show a novel role for IL-10 beyond its accepted immune-regulatory mechanism. The opportunity for IL-10 to regulate a fibroblast-specific formation of a regenerative, HA-rich wound extracellular matrix may lead to the development of innovative therapies to attenuate postnatal fibrosis in organ systems or diseases in which dysregulated inflammation and HA intersect.-Balaji, S., Wang, X., King, A., Le, L. D., Bhattacharya, S. S., Moles, C. M., Butte, M. J., de Jesus Perez, V. A., Liechty, K. W., Wight, T. N., Crombleholme, T. M., Bollyky, P. L., Keswani, S. G. Interleukin-10-mediated regenerative postnatal tissue repair is dependent on regulation of hyaluronan metabolism via fibroblast-specific STAT3 signaling. © The Author(s).

  12. Semi-permeable membrane retention of synovial fluid lubricants hyaluronan and proteoglycan 4 for a biomimetic bioreactor.

    Science.gov (United States)

    Blewis, Megan E; Lao, Brian J; Jadin, Kyle D; McCarty, William J; Bugbee, William D; Firestein, Gary S; Sah, Robert L

    2010-05-01

    Synovial fluid (SF) contains lubricant macromolecules, hyaluronan (HA), and proteoglycan 4 (PRG4). The synovium not only contributes lubricants to SF through secretion by synoviocyte lining cells, but also concentrates lubricants in SF due to its semi-permeable nature. A membrane that recapitulates these synovium functions may be useful in a bioreactor system for generating a bioengineered fluid (BF) similar to native SF. The objectives were to analyze expanded polytetrafluoroethylene membranes with pore sizes of 50 nm, 90 nm, 170 nm, and 3 microm in terms of (1) HA and PRG4 secretion rates by adherent synoviocytes, and (2) the extent of HA and PRG4 retention with or without synoviocytes adherent on the membrane. Experiment 1: Synoviocytes were cultured on tissue culture (TC) plastic or membranes +/- IL-1beta + TGF-beta1 + TNF-alpha, a cytokine combination that stimulates lubricant synthesis. HA and PRG4 secretion rates were assessed by analysis of medium. Experiment 2: Bioreactors were fabricated to provide a BF compartment enclosed by membranes +/- adherent synoviocytes, and an external compartment of nutrient fluid (NF). A solution with HA (1 mg/mL, MW ranging from 30 to 4,000 kDa) or PRG4 (50 microg/mL) was added to the BF compartment, and HA and PRG4 loss into the NF compartment after 2, 8, and 24 h was determined. Lubricant loss kinetics were analyzed to estimate membrane permeability. Experiment 1: Cytokine-regulated HA and PRG4 secretion rates on membranes were comparable to those on TC plastic. Experiment 2: Transport of HA and PRG4 across membranes was lowest with 50 nm membranes and highest with 3 microm membranes, and transport of high MW HA was decreased by adherent synoviocytes (for 50 and 90 nm membranes). The permeability to HA mixtures for 50 nm membranes was approximately 20 x 10(-8) cm/s (- cells) and approximately 5 x 10(-8) cm/s (+ cells), for 90 nm membranes was approximately 35 x 10(-8) cm/s (- cells) and approximately 19 x 10(-8) cm

  13. Relationship between cyclooxygenase-2 and human epidermal growth factor receptor 2 in vascular endothelial growth factor C up-regulation and lymphangiogenesis in human breast cancer.

    Science.gov (United States)

    Bhattacharjee, Rabindra N; Timoshenko, Alexander V; Cai, Jing; Lala, Peeyush K

    2010-09-01

    Both cyclooxygenase (COX)-2 and human epidermal growth factor receptor (HER)-2 promote breast cancer progression; however, the relationship between the two molecules remains unclear. We utilized human breast cancer tissues and cell lines to examine whether COX-2 and HER-2 played independent or interdependent roles in vascular endothelial growth factor (VEGF)-C up-regulation and lymphangiogenesis. A paired correlation of immunodetectable levels of COX-2, VEGF-C, and HER-2 proteins and lymphovascular density (LVD; D2-40-immunolabeled) in 55 breast cancer specimens revealed a positive correlation between COX-2 and HER-2 irrespective of clinicopathological status. However COX-2 alone positively correlated with LVD. In 10 independent specimens, mRNA levels showed a positive correlation between HER-2 and COX-2 or VEGF-C but not LYVE-1 (lymphovascular endothelial marker). These findings implicate COX-2, but not HER-2, in breast cancer-associated lymphangiogenesis. Manipulation of the COX-2 or HER-2 genes in breast cancer cell lines varying widely in COX-2 and HER-2 expression revealed a direct role of COX-2 and an indirect COX-2 dependent role of HER-2 in VEGF-C up-regulation: (i) high VEGF-C expression in high COX-2/low HER-2 expressing MDA-MB-231 cells was reduced by siRNA-mediated down-regulation of COX-2, but not HER-2; (ii) integration of HER-2 in these cells simultaneously up-regulated COX-2 protein as well as VEGF-C secretion; and (iii) low VEGF-C secretion by high HER-2/low COX-2 expressing SK-BR-3 cells was stimulated by COX-2 overexpression. These findings of the primary role of COX-2 and the COX-2-dependent role of HER-2, if any, in VEGF-C up-regulation and lymphangiogenesis suggest that COX-2 inhibitors may abrogate lymphatic metastasis in breast cancer irrespective of HER-2 status. © 2010 Japanese Cancer Association.

  14. CD147, CD44, and the epidermal growth factor receptor (EGFR) signaling pathway cooperate to regulate breast epithelial cell invasiveness.

    Science.gov (United States)

    Grass, G Daniel; Tolliver, Lauren B; Bratoeva, Momka; Toole, Bryan P

    2013-09-06

    The immunoglobulin superfamily glycoprotein CD147 (emmprin; basigin) is associated with an invasive phenotype in various types of cancers, including malignant breast cancer. We showed recently that up-regulation of CD147 in non-transformed, non-invasive breast epithelial cells is sufficient to induce an invasive phenotype characterized by membrane type-1 matrix metalloproteinase (MT1-MMP)-dependent invadopodia activity (Grass, G. D., Bratoeva, M., and Toole, B. P. (2012) Regulation of invadopodia formation and activity by CD147. J. Cell Sci. 125, 777-788). Here we found that CD147 induces breast epithelial cell invasiveness by promoting epidermal growth factor receptor (EGFR)-Ras-ERK signaling in a manner dependent on hyaluronan-CD44 interaction. Furthermore, CD147 promotes assembly of signaling complexes containing CD147, CD44, and EGFR in lipid raftlike domains. We also found that oncogenic Ras regulates CD147 expression, hyaluronan synthesis, and formation of CD147-CD44-EGFR complexes, thus forming a positive feedback loop that may amplify invasiveness. Last, we showed that malignant breast cancer cells are heterogeneous in their expression of surface-associated CD147 and that high levels of membrane CD147 correlate with cell surface EGFR and CD44 levels, activated EGFR and ERK1, and activated invadopodia. Future studies should evaluate CD147 as a potential therapeutic target and disease stratification marker in breast cancer.

  15. Somatostatin receptors

    DEFF Research Database (Denmark)

    Møller, Lars Neisig; Stidsen, Carsten Enggaard; Hartmann, Bolette

    2003-01-01

    therefore been acknowledged to be a third endogenous ligand at SRIF receptors. This review goes through mechanisms of signal transduction, pharmacology, and anatomical distribution of SRIF receptors. Structurally, SRIF receptors belong to the superfamily of G protein-coupled (GPC) receptors, sharing....... The generation of knock-out (KO) mice, intended as a means to define the contributions made by individual receptor subtypes, necessarily marks but an approximation. Furthermore, we must now take into account the stunning complexity of receptor co-operation indicated by the observation of receptor homo......-peptides, receptor agonists and antagonists. Relatively long half lives, as compared to those of the endogenous ligands, have been paramount from the outset. Motivated by theoretical puzzles or the shortcomings of present-day diagnostics and therapy, investigators have also aimed to produce subtype...

  16. VEGF-C and TGF-β reciprocally regulate mesenchymal stem cell commitment to differentiation into lymphatic endothelial or osteoblastic phenotypes.

    Science.gov (United States)

    Igarashi, Yasuyuki; Chosa, Naoyuki; Sawada, Shunsuke; Kondo, Hisatomo; Yaegashi, Takashi; Ishisaki, Akira

    2016-04-01

    The direction of mesenchymal stem cell (MSC) differentiation is regulated by stimulation with various growth factors and cytokines. We recently established MSC lines, [transforming growth factor-β (TGF-β)-responsive SG‑2 cells, bone morphogenetic protein (BMP)-responsive SG‑3 cells, and TGF-β/BMP-non-responsive SG‑5 cells], derived from the bone marrow of green fluorescent protein-transgenic mice. In this study, to compare gene expression profiles in these MSC lines, we used DNA microarray analysis to characterize the specific gene expression profiles observed in the TGF-β-responsive SG‑2 cells. Among the genes that were highly expressed in the SG‑2 cells, we focused on vascular endothelial growth factor (VEGF) receptor 3 (VEGFR3), the gene product of FMS-like tyrosine kinase 4 (Flt4). We found that VEGF-C, a specific ligand of VEGFR3, significantly induced the cell proliferative activity, migratory ability (as shown by Transwell migration assay), as well as the phosphorylation of extracellular signal-regulated kinase (ERK)1/2 in the SG‑2 cells. Additionally, VEGF-C significantly increased the expression of prospero homeobox 1 (Prox1) and lymphatic vessel endothelial hyaluronan receptor 1 (Lyve1), which are lymphatic endothelial cell markers, and decreased the expression of osteogenic differentiation marker genes in these cells. By contrast, TGF-β significantly increased the expression of early-phase osteogenic differentiation marker genes in the SG‑2 cells and markedly decreased the expression of lymphatic endothelial cell markers. The findings of our study strongly suggest the following: i) that VEGF-C promotes the proliferative activity and migratory ability of MSCs; and ii) VEGF-C and TGF-β reciprocally regulate MSC commitment to differentiation into lymphatic endothelial or osteoblastic phenotypes, respectively. Our findings provide new insight into the molecular mechanisms underlying the regenerative ability of MSCs.

  17. Both hyaluronan and collagen type II keep proteoglycan 4 (lubricin) at the cartilage surface in a condition that provides low friction during boundary lubrication.

    Science.gov (United States)

    Majd, Sara Ehsani; Kuijer, Roel; Köwitsch, Alexander; Groth, Thomas; Schmidt, Tannin A; Sharma, Prashant K

    2014-12-09

    Wear resistant and ultralow friction in synovial joints is the outcome of a sophisticated synergy between the major macromolecules of the synovial fluid, e.g., hyaluronan (HA) and proteoglycan 4 (PRG4), with collagen type II fibrils and other non-collagenous macromolecules of the cartilage superficial zone (SZ). This study aimed at better understanding the mechanism of PRG4 localization at the cartilage surface. We show direct interactions between surface bound HA and freely floating PRG4 using the quartz crystal microbalance with dissipation (QCM-D). Freely floating PRG4 was also shown to bind with surface bound collagen type II fibrils. Albumin, the most abundant protein of the synovial fluid, effectively blocked the adsorption of PRG4 with HA, through interaction with C and N terminals on PRG4, but not that of PRG4 with collagen type II fibrils. The above results indicate that collagen type II fibrils strongly contribute in keeping PRG4 in the SZ during cartilage articulation in situ. Furthermore, PRG4 molecules adsorbed very well on mimicked SZ of absorbed HA molecules with entangled collagen type II fibrils and albumin was not able to block this interaction. In this last condition PRG4 adsorption resulted in a coefficient of friction (COF) of the same order of magnitude as the COF of natural cartilage, measured with an atomic force microscope in lateral mode.

  18. Adequacy of hyaluronan binding assay and a new fertility index derived from it for measuring of male fertility potential and the efficacy of supplement therapy.

    Science.gov (United States)

    Szucs, M; Osvath, P; Laczko, I; Jakab, A

    2015-06-01

    The aim of the study was to statistically prove that the HBA(®) test is an efficient practical method for andrologists to determine the fertility potential as well as to measure the efficiency of oral supplement therapy in case of male infertility. In the study, 175 patients were involved and it also included the follow-up studies of 39 patients after supplement therapy. Completing the 'classic' spermatological parameters with the results of HBA(®) test, the authors have also determined a new fertility index to be used for practical rating of the measure of fertility potential. After the supplement therapy, both sperm density and hyaluronan binding capacity increased significantly. The authors are convinced that the HBA(®) analysis is an objective, standardisable test, which provides a better approach to fertility potential. This analysis enables us to detect spermatozoa that were previously misjudged as normal by morphological assay and also makes the efficiency of the therapy more measurable. © 2014 Blackwell Verlag GmbH.

  19. NCBI nr-aa BLAST: CBRC-DNOV-01-2020 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available minin-type EGF-like and link domain-containing scavenger receptor 2) (FEEL-2) (Hyaluronan receptor for endocytosis...) [Contains: 175 kDa stabilin-2 (175 kDa hyaluronan receptor for endocytosis)] gb|AAG13634.1| hyaluronan receptor for endocytos...is HARE precursor [Rattus norvegicus] Q8CFM6 1e-16 90% ...

  20. NOK/STYK1 promotes the genesis and remodeling of blood and lymphatic vessels during tumor progression.

    Science.gov (United States)

    Liu, Yue; Li, Tianqi; Hu, Dan; Zhang, Shuping

    2016-09-01

    Previous studies have indicated that the overexpression of NOK, also named STYK1, led to tumorigenesis and metastasis. Here, we provide evidence that increased expression of NOK/STYK1 caused marked alterations in the overall and inner structures of tumors and substantially facilitates the genesis and remodeling of the blood and lymphatic vessels during tumor progression. In particular, NOK-expressed HeLa stable cells (HeLa-K) significantly enhanced tumor growth and metastasis in xenografted nude mice. Hematoxylin and eosin (HE) staining demonstrated that the tumor tissues generated by HeLa-K cells were much more ichorous and had more interspaces than those generated by control HeLa cells (HeLa-C). The fluorescent areas stained with cluster of differentiation 31 (CD31), a marker protein for blood vessels, appeared to be in different patterns. The total blood vessels, especially the ring patterns, within the tumors of the HeLa-K group were highly enriched compared with those in the HeLa-C group. NOK-HA was demonstrated to be well colocalized with CD31 in the wall of the tubular structures within tumor tissues. Interestingly, antibody staining of the lymphatic vessel endothelial hyaluronan receptor (LYVE-1) further revealed the increase in ring (oratretic strip-like) lymphatic vessels in either the peritumoral or intratumoral areas in the HeLa-K group compared with the HeLa-C group. Consistently, the analysis of human cancerous tissue also showed that NOK was highly expressed in the walls of tubular structures. Thus, our results reveal a novel tumorigenic function of NOK to mediate the genesis and remodeling of blood and lymphatic vessels during tumor progression.

  1. SwissProt search result: AK060289 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK060289 001-006-C12 (Q00547) Hyaluronan mediated motility receptor (Intracellular ...hyaluronic acid binding protein) (Receptor for hyaluronan-mediated motility) HMMR_MOUSE 9e-12 ...

  2. SwissProt search result: AK073937 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK073937 J033075G21 (Q00547) Hyaluronan mediated motility receptor (Intracellular h...yaluronic acid binding protein) (Receptor for hyaluronan-mediated motility) HMMR_MOUSE 3e-13 ...

  3. SwissProt search result: AK106271 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK106271 002-100-G09 (Q00547) Hyaluronan mediated motility receptor (Intracellular ...hyaluronic acid binding protein) (Receptor for hyaluronan-mediated motility) HMMR_MOUSE 8e-16 ...

  4. SwissProt search result: AK106271 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK106271 002-100-G09 (O75330) Hyaluronan mediated motility receptor (Intracellular ...hyaluronic acid binding protein) (Receptor for hyaluronan-mediated motility) (CD168 antigen) HMMR_HUMAN 6e-17 ...

  5. SwissProt search result: AK067565 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK067565 J013112J12 (O75330) Hyaluronan mediated motility receptor (Intracellular h...yaluronic acid binding protein) (Receptor for hyaluronan-mediated motility) (CD168 antigen) HMMR_HUMAN 2e-12 ...

  6. SwissProt search result: AK066964 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK066964 J013092J24 (Q00547) Hyaluronan mediated motility receptor (Intracellular h...yaluronic acid binding protein) (Receptor for hyaluronan-mediated motility) HMMR_MOUSE 2e-15 ...

  7. SwissProt search result: AK240924 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240924 J065039N21 (Q00547) Hyaluronan mediated motility receptor (Intracellular h...yaluronic acid binding protein) (Receptor for hyaluronan-mediated motility) HMMR_MOUSE 2e-15 ...

  8. SwissProt search result: AK063431 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK063431 001-115-D10 (Q00547) Hyaluronan mediated motility receptor (Intracellular ...hyaluronic acid binding protein) (Receptor for hyaluronan-mediated motility) HMMR_MOUSE 2e-14 ...

  9. SwissProt search result: AK063431 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK063431 001-115-D10 (O75330) Hyaluronan mediated motility receptor (Intracellular ...hyaluronic acid binding protein) (Receptor for hyaluronan-mediated motility) (CD168 antigen) HMMR_HUMAN 1e-14 ...

  10. SwissProt search result: AK063431 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK063431 001-115-D10 (P97779) Hyaluronan mediated motility receptor (Intracellular ...hyaluronic acid binding protein) (Receptor for hyaluronan-mediated motility) HMMR_RAT 2e-12 ...

  11. SwissProt search result: AK067565 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK067565 J013112J12 (Q00547) Hyaluronan mediated motility receptor (Intracellular h...yaluronic acid binding protein) (Receptor for hyaluronan-mediated motility) HMMR_MOUSE 9e-15 ...

  12. SwissProt search result: AK240924 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK240924 J065039N21 (O75330) Hyaluronan mediated motility receptor (Intracellular h...yaluronic acid binding protein) (Receptor for hyaluronan-mediated motility) (CD168 antigen) HMMR_HUMAN 7e-11 ...

  13. 口服透明质酸对皮肤水分的改善作用及体内抗氧化作用研究%Improving Effect of Oral Hyaluronan on Skin Moisture and Its Antioxidation Functionin vivo

    Institute of Scientific and Technical Information of China (English)

    冯宁; 石艳丽; 郭风仙; 郭学平

    2016-01-01

    Objective To study the effect of oral hyaluronan on skin moisture and its antioxidation functionin vivo, as well as its safety.Methods In this double-blind clinical study, the subjects were divided into trial group and control group, respectively. The skin moisture and serum MDA, SOD, GSH-Px levels and other biochemical indices were analyzed before and after test. Results Skin moisture of the hyaluronan treated group after test increased significantly compared with that before test and the placebo treated group (P<0.05). Serum SOD in trial group increased significantly after test (P<0.05). The safety indices of the subjects were within the normal range in the hyaluronan treated groups.Conclusion Oral hyaluronan can improve the skin moisture, and has high antioxidant activity and high safetyin vivo.%目的:考察口服透明质酸(HA)对皮肤水分的改善作用、体内抗氧化作用及安全性。方法按双盲法进行人体试食试验,分为试食组与对照组,分析两组受试者皮肤水分及血清中丙二醛(MDA)、超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)的含量变化,并对受试者身体情况和各生化指标进行安全性考察。结果试食组的皮肤水分明显提高,与试食前和对照组比较,差异均有统计学意义(P<0.05);试食组血清SOD活性与对照组试食后及自身试验前比较,差异均有统计学意义(P<0.05);受试者安全性指标均在正常范围内。结论口服HA可改善人体皮肤水分,具有体内抗氧化作用,且口服安全性高。

  14. Lipoxin Receptors

    Directory of Open Access Journals (Sweden)

    Mario Romano

    2007-01-01

    Full Text Available Lipoxins (LXs represent a class of arachidonic acid (AA metabolites that carry potent immunoregulatory and anti-inflammatory properties, LXA4 and LXB4 being the main components of this series. LXs are generated by cooperation between 5-lipoxygenase (LO and 12- or 15-LO during cell-cell interactions or by single cell types. LX epimers at carbon 15, the 15-epi-LXs, are formed by aspirin-acetylated cyclooxygenase-2 (COX-2 in cooperation with 5-LO. 15-epi-LXA4 is also termed aspirin-triggered LX (ATL. In vivo studies with stable LX and ATL analogs have established that these eicosanoids possess potent anti-inflammatory activities. A LXA4 receptor has been cloned. It belongs to the family of chemotactic receptors and clusters with formyl peptide receptors on chromosome 19. Therefore, it was initially denominated formyl peptide receptor like 1 (FPRL1. This receptor binds with high affinity and stereoselectivity LXA4 and ATL. It also recognizes a variety of peptides, synthetic, endogenously generated, or disease associated, but with lower affinity compared to LXA4. For this reason, this receptor has been renamed ALX. This review summarizes the current knowledge on ALX expression, signaling, and potential pathophysiological role. The involvement of additional recognition sites in LX bioactions is also discussed.

  15. Rheology and Confocal Reflectance Microscopy as Probes of Mechanical Properties and Structure during Collagen and Collagen/Hyaluronan Self-Assembly

    Science.gov (United States)

    Yang, Ya-li; Kaufman, Laura J.

    2009-01-01

    In this work, the gelation of three-dimensional collagen and collagen/hyaluronan (HA) composites is studied by time sweep rheology and time lapse confocal reflectance microscopy (CRM). To investigate the complementary nature of these techniques, first collagen gel formation is investigated at concentrations of 0.5, 1.0, and 1.5 mg/mL at 37°C and 32°C. The following parameters are used to describe the self-assembly process in all gels: the crossover time (tc), the slope of the growth phase (kg), and the arrest time (ta). The first two measures are determined by rheology, and the third by CRM. A frequency-independent rheological measure of gelation, tg, is also measured at 37°C. However, this quantity cannot be straightforwardly determined for gels formed at 32°C, indicating that percolation theory does not fully capture the dynamics of collagen network formation. The effects of collagen concentration and gelation temperature on kg, tc, and ta as well as on the mechanical properties and structure of these gels both during gelation and at equilibrium are elucidated. Composite collagen/HA gels are also prepared, and their properties are monitored at equilibrium and during gelation at 37°C and 32°C. We show that addition of HA subtly alters mechanical properties and structure of these systems both during the gelation process and at equilibrium. This occurs in a temperature-dependent manner, with the ratio of HA deposited on collagen fibers versus that distributed homogeneously between fibers increasing with decreasing gelation temperature. In addition to providing information on collagen and collagen/HA structure and mechanical properties during gelation, this work shows new ways in which rheology and microscopy can be used complementarily to reveal details of gelation processes. PMID:19217873

  16. Heavy Chain-Hyaluronan/Pentraxin 3 from Amniotic Membrane Suppresses Inflammation and Scarring in Murine Lacrimal Gland and Conjunctiva of Chronic Graft-versus-Host Disease

    Science.gov (United States)

    Ogawa, Yoko; He, Hua; Mukai, Shin; Imada, Toshihiro; Nakamura, Shigeru; Su, Chen-Wei; Mahabole, Megha; Tseng, Scheffer C. G.; Tsubota, Kazuo

    2017-01-01

    Chronic graft-versus-host disease (cGVHD) is a major complication of hematopoietic stem cell transplantation. Dry eye disease is the prominent ocular sequel of cGVHD and is caused by excessive inflammation and fibrosis in the lacrimal glands. Heavy chain-Hyaluronan/Pentraxin 3 (HC-HA/PTX3) is a complex purified from human amniotic membrane (AM) and known to exert anti-inflammatory and anti-scarring actions. In this study, we utilized a mouse model of cGVHD to examine whether HC-HA/PTX3 could attenuate dry eye disease elicited by cGVHD. Our results indicated that subconjunctival and subcutaneous injection of HC-HA/PTX3 preserved tear secretion and conjunctival goblet cell density and mitigated inflammation and scarring of the conjunctiva. Such therapeutic benefits were associated with suppression of scarring and infiltration of inflammatory/immune cells in the lacrimal glands. Furthermore, HC-HA/PTX3 significantly reduced the extent of infiltration of CD45+ CD4+ IL-17+ cells, CD45+ CD34+ collagen I+ CXCR4+ fibrocytes, and HSP47+ activated fibroblasts that were accompanied by upregulation of collagen type Iα1, collagen type IIIα1 and NF-kB in lacrimal glands. Collectively, these pre-clinical data help prove the concept that subcutaneous and subconjunctival injection of HC-HA/PTX3 is a novel approach to prevent dry eye disease caused by cGVHD and allow us to test its safety and efficacy in future human clinical trials. PMID:28165063

  17. Efficacy of platelet-rich plasma gel and hyaluronan hydrogel as carriers of electrically polarized hydroxyapatite microgranules for accelerating bone formation.

    Science.gov (United States)

    Ohba, Seiko; Wang, Wei; Itoh, Soichiro; Takagi, Yuzo; Nagai, Akiko; Yamashita, Kimihiro

    2012-11-01

    The technology for electrical polarization and characterization of hydroxyapatite (HA) microgranules has been developed. This study aimed to examine and compare the efficacy of composites comprising electrically polarized HA (pHA) microgranules and platelet-rich plasma (PRP) or hyaluronan (HAN) in osteoconductivity. Composites of HA microgranules with or without electrical polarization and either PRP or HAN (PRP+pHA, PRP+HA, HAN+pHA, and HAN+HA, respectively), as well as pHA and HA microgranules were implanted randomly into holes created in the medial femoral condyle or tibial tuberosity of rabbits. As a control, PRP or HAN gel alone was implanted, or the bone holes were left empty. Each group included six animals. After 6 weeks, histological examination was performed, and osteoclastic and osteoblastic cell activities were assessed by cell counting. Although PRP alone could not induce bone formation, PRP+pHA and PRP+HA composites, especially the former, activated osteogenic cells and enhanced bone formation. This effect was not prominent in the HAN+pHA and HAN+HA composites. PRP+HA composites formed a gel in which the ceramic particles were dispersed and entrapped in the fibrin network of PRP. It is assumed that these particles provide scaffolds for osteogenic cells, and when electrically polarized, can activate the cells in co-operation with the positive effects of the PRP, resulting in enhanced bone formation. Conversely, it is conceivable that this composite gel cannot act as an accelerator for woven bone formation, because HAN with low viscoelasticity is absorbed rapidly after implantation, the hydrated network containing HA microgranules is destroyed, and the HA microgranules effuse with HAN from the bone hole.

  18. Effects of leflunomide on hyaluronan synthases (HAS): NF-kappa B-independent suppression of IL-1-induced HAS1 transcription by leflunomide.

    Science.gov (United States)

    Stuhlmeier, Karl M

    2005-06-01

    Despite evidence that points to unfettered hyaluronic acid (HA) production as a culprit in the progression of rheumatic disorders, little is known about differences in regulation and biological functions of the three hyaluronan synthase (HAS) genes. Testing the effects of drugs with proven anti-inflammatory effects could help to clarify biological functions of these genes. In this study, we demonstrate that leflunomide suppresses HA release in fibroblast-like synoviocytes (FLS) in a dose-dependent manner. We further demonstrate that leflunomide suppresses HA synthase activity, as determined by (14)C-glucuronic acid incorporation assays. Additional experiments revealed that in FLS, leflunomide specifically blocked the induction of HAS1. HAS2 and HAS3, genes that are, in contrast to HAS1, constitutively expressed in FLS, are not significantly affected. Leflunomide can function as a NF-kappaB inhibitor. However, EMSA experiments demonstrate that at the concentrations used, leflunomide neither interferes with IL-1beta- nor with PMA-induced NF-kappaB translocation. Furthermore, reconstituting the pyrimidine synthase pathway did not lead to the restoration of IL-1beta-induced HAS1 activation. More importantly, two tyrosine kinase inhibitors mimicked the effect of leflunomide in that both blocked IL-1beta-induced HAS1 activation without affecting HAS2 or HAS3. These data point at HAS1 activation as the possible cause for unfettered HA production in rheumatoid arthritis and might explain, at least in part, the beneficial effects of leflunomide treatment. These findings also support the concept that IL-1beta-induced HAS1 activation depends on the activation of tyrosine kinases, and indicate that leflunomide blocks HA release by suppressing tyrosine kinases rather than through inhibition of NF-kappaB translocation.

  19. Placental stem cells pre-treated with a hyaluronan mixed ester of butyric and retinoic acid to cure infarcted pig hearts: a multimodal study.

    Science.gov (United States)

    Simioniuc, Anca; Campan, Manuela; Lionetti, Vincenzo; Marinelli, Martina; Aquaro, Giovanni D; Cavallini, Claudia; Valente, Sabrina; Di Silvestre, Dario; Cantoni, Silvia; Bernini, Fabio; Simi, Claudia; Pardini, Silvia; Mauri, Pierluigi; Neglia, Danilo; Ventura, Carlo; Pasquinelli, Gianandrea; Recchia, Fabio A

    2011-06-01

    Pre-treating placenta-derived human mesenchymal stem cells (FMhMSCs) with a hyaluronan mixed ester of butyric and retinoic acid (HBR) potentiates their reparative capacity in rodent hearts. Our aim was to test FMhMSCs in a large-animal model by employing a novel combination of in vivo and ex vivo analyses. Matched regional quantifications of myocardial function and viability were performed by magnetic resonance imaging (MRI) and positron emission tomography (PET) 4 weeks after myocardial infarction combined with intramyocardial injection of FMhMSCs (n = 7), or HBR-pre-treated FMhMSCs (HBR-FMhMSCs, n = 6), or saline solution (PBS, n = 7). Sham-operated pigs (n = 4) were used as control animals. Despite no differences in the ejection fraction and haemodynamics, regional MRI revealed, in pigs treated with HBR-FMhMSCs compared with the other infarcted groups, a 40% smaller infarct scar size and a significant improvement of the end-systolic wall thickening and circumferential shortening of the infarct border zone. Consistently, PET showed that myocardial perfusion and glucose uptake were, respectively, 35 and 23% higher in the border zone of pigs treated with HBR-FMhMSCs compared with the other infarcted groups. Histology supported in vivo imaging; the delivery of HBR-FMhMSCs significantly enhanced capillary density and decreased fibrous tissue by approximately 68%. Moreover, proteomic analysis of the border zone in the HBR-FMhMSCs group and the FMhMSCs group indicated, respectively, 45 and 30% phenotypic homology with healthy tissue, while this homology was only 26% in the border zone of the PBS group. Our results support a more pronounced reparative potential of HBR-pre-treated FMhMSCs in a clinically relevant animal model of infarction and highlight the necessity of using combined diagnostic imaging to avoid underestimations of stem cell therapeutic effects in the heart.

  20. Comparison of Peritendinous Hyaluronan Injections Versus Extracorporeal Shock Wave Therapy in the Treatment of Painful Achilles' Tendinopathy: A Randomized Clinical Efficacy and Safety Study.

    Science.gov (United States)

    Lynen, Nils; De Vroey, Thierry; Spiegel, Imke; Van Ongeval, Frederik; Hendrickx, Niels-Jan; Stassijns, Gaëtane

    2017-01-01

    To compare the safety and efficacy of hyaluronan (HA) injections with standard extracorporeal shock wave therapy (ESWT) in the treatment of painful midportion Achilles' tendinopathy. Multinational, prospective, randomized controlled, blinded-observer trial. Ambulatory care. Adults (N=62) with Achilles' midportion tendinopathy for ≥6 weeks and a pain score of at least 40mm (Huskisson visual analog scale [VAS], 100mm) were randomized, and 59 were analyzed in the intention-to-treat data set. There were no withdrawals because of adverse effects. Two peritendinous HA injections versus 3 ESWT applications at weekly intervals. Primary efficacy criterion was changed from the Victorian Institute of Sports Assessment-Achilles' questionnaire (VISA-A) score to the percent change in pain (VAS) at 3 months posttreatment, compared with baseline values. Main secondary parameters were VISA-A, Clinical Global Impression (CGI), and clinical parameters. HA treatment provided a clinically relevant improvement in Achilles' midportion tendinopathy. A large superiority of the HA group, compared with ESWT application, was observed for percent change in pain (VAS), and this superiority was proven to be statistically significant (Mann-Whitney statistic [MW]=.7507 with P=.0030 lower than required α=.025 significance level 1-sided; Mann-Whitney U test) at 3 months posttreatment. Similar findings for HA were also observed at 4 weeks (MW=.6425, P=.0304) and 6 months (MW=.7172, P=.0018). Advantage of HA treatment was confirmed by VISA-A questionnaire, CGI, and clinical parameters. Ten adverse events, 4 in the HA group and 6 in the ESWT group, were reported, but none were classified as serious. Two peritendinous HA injections showed greater treatment success in Achilles' midportion tendinopathy compared with standard ESWT. Copyright © 2016 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

  1. Efficacy of intravenous administration of hyaluronan, sodium chondroitin sulfate, and N-acetyl-d-glucosamine for prevention or treatment of osteoarthritis in horses.

    Science.gov (United States)

    Frisbie, David D; McIlwraith, C Wayne; Kawcak, Christopher E; Werpy, Natasha M

    2016-10-01

    OBJECTIVE To evaluate the efficacy of IV administration of a product containing hyaluronan, sodium chondroitin sulfate, and N-acetyl-d-glucosamine for prevention or treatment of osteoarthritis in horses. ANIMALS 32 healthy 2- to 5-year-old horses. PROCEDURES The study involved 2 portions. To evaluate prophylactic efficacy of the test product, horses received 5 mL of the product (n = 8) or saline (0.9% NaCl) solution (8; placebo) IV every fifth day, starting on day 0 (when osteoarthritis was induced in the middle carpal joint of 1 forelimb) and ending on day 70. To evaluate treatment efficacy, horses received either the product or placebo (n = 8/treatment) on days 16, 23, 30, 37, and 44 after osteoarthritis induction. Clinical, diagnostic imaging, synovial fluid, gross anatomic, and histologic evaluations and other tests were performed. Results of each study portion were compared between treatment groups. RESULTS Limb flexion and radiographic findings were significantly worse for horses that received the test product in the prophylactic efficacy portion than for placebo-treated horses or product-treated horses in the treatment efficacy portion. In the prophylactic efficacy portion, significantly less articular cartilage erosion was identified in product-treated versus placebo-treated horses. In the treatment efficacy portion, joints of product-treated horses had a greater degree of bone edema identified via MRI than did joints of placebo-treated horses but fewer microscopic articular cartilage abnormalities. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that caution should be used when administering the evaluated product IV to horses, particularly when administering it prophylactically, as it may have no benefit or may even cause harm.

  2. Towards a structure for a TSG-6.hyaluronan complex by modeling and NMR spectroscopy: insights into other members of the link module superfamily.

    Science.gov (United States)

    Blundell, Charles D; Almond, Andrew; Mahoney, David J; DeAngelis, Paul L; Campbell, Iain D; Day, Anthony J

    2005-05-06

    The Link module from human TSG-6, a hyaladherin with roles in ovulation and inflammation, has a hyaluronan (HA)-binding groove containing two adjacent tyrosine residues that are likely to form CH-pi stacking interactions with sequential rings in the sugar. We have used this observation to construct a model of a protein.HA complex, which was then tested against existing experimental information and by acquisition of new NMR data sets of [(13)C, (15)N]HA (8-mer) complexed with unlabeled protein. A major finding of this analysis was that acetamido side chains of two GlcNAc rings fit into hydrophobic pockets on either side of the adjacent tyrosines, providing a selectivity mechanism of HA over other polysaccharides. Furthermore, two basic residues have a separation that matches that of glucuronic acids in the sugar, consistent with the formation of salt bridges; NMR experiments at a range of pH values identified protein groups that titrate due to their proximity to a free carboxylate in HA. Sequence alignment and construction of homology models for all human Link modules in their HA-bound states revealed that many of these features are conserved across the superfamily, thus allowing the prediction of functionally important residues. In the case of cartilage link protein, its two Link modules were docked together (using bound HA as a guide), identifying hydrophobic residues likely to form an intra-Link module interface as well as amino acids that could be involved in supporting intermolecular interactions between link proteins and chondroitin sulfate proteoglycans. Here, we propose a mechanism for ternary complex formation that generates higher order helical structures, as may exist in cartilage aggregates.

  3. The role of interleukin-10 and hyaluronan in murine fetal fibroblast function in vitro: implications for recapitulating fetal regenerative wound healing.

    Science.gov (United States)

    Balaji, Swathi; King, Alice; Marsh, Emily; LeSaint, Maria; Bhattacharya, Sukanta S; Han, Nathaniel; Dhamija, Yashu; Ranjan, Rajeev; Le, Louis D; Bollyky, Paul L; Crombleholme, Timothy M; Keswani, Sundeep G

    2015-01-01

    Mid-gestation fetal cutaneous wounds heal scarlessly and this has been attributed in part to abundant hyaluronan (HA) in the extracellular matrix (ECM) and a unique fibroblast phenotype. We recently reported a novel role for interleukin 10 (IL-10) as a regulator of HA synthesis in the fetal ECM, as well as the ability of the fetal fibroblast to produce an HA-rich pericellular matrix (PCM). We hypothesized that IL-10-mediated HA synthesis was essential to the fetal fibroblast functional phenotype and, moreover, that this phenotype could be recapitulated in adult fibroblasts via supplementation with IL-10 via an HA dependent process. To evaluate the differences in functional profile, we compared metabolism (MTS assay), apoptosis (caspase-3 staining), migration (scratch wound assay) and invasion (transwell assay) between C57Bl/6J murine fetal (E14.5) and adult (8 weeks) fibroblasts. We found that fetal fibroblasts have lower rates of metabolism and apoptosis, and an increased ability to migrate and invade compared to adult fibroblasts, and that these effects were dependent on IL-10 and HA synthase activity. Further, addition of IL-10 to adult fibroblasts resulted in increased fibroblast migration and invasion and recapitulated the fetal phenotype in an HA-dependent manner. Our data demonstrates the functional differences between fetal and adult fibroblasts, and that IL-10 mediated HA synthesis is essential for the fetal fibroblasts' enhanced invasion and migration properties. Moreover, IL-10 via an HA-dependent mechanism can recapitulate this aspect of the fetal phenotype in adult fibroblasts, suggesting a novel mechanism of IL-10 in regenerative wound healing.

  4. The role of interleukin-10 and hyaluronan in murine fetal fibroblast function in vitro: implications for recapitulating fetal regenerative wound healing.

    Directory of Open Access Journals (Sweden)

    Swathi Balaji

    Full Text Available Mid-gestation fetal cutaneous wounds heal scarlessly and this has been attributed in part to abundant hyaluronan (HA in the extracellular matrix (ECM and a unique fibroblast phenotype. We recently reported a novel role for interleukin 10 (IL-10 as a regulator of HA synthesis in the fetal ECM, as well as the ability of the fetal fibroblast to produce an HA-rich pericellular matrix (PCM. We hypothesized that IL-10-mediated HA synthesis was essential to the fetal fibroblast functional phenotype and, moreover, that this phenotype could be recapitulated in adult fibroblasts via supplementation with IL-10 via an HA dependent process.To evaluate the differences in functional profile, we compared metabolism (MTS assay, apoptosis (caspase-3 staining, migration (scratch wound assay and invasion (transwell assay between C57Bl/6J murine fetal (E14.5 and adult (8 weeks fibroblasts. We found that fetal fibroblasts have lower rates of metabolism and apoptosis, and an increased ability to migrate and invade compared to adult fibroblasts, and that these effects were dependent on IL-10 and HA synthase activity. Further, addition of IL-10 to adult fibroblasts resulted in increased fibroblast migration and invasion and recapitulated the fetal phenotype in an HA-dependent manner.Our data demonstrates the functional differences between fetal and adult fibroblasts, and that IL-10 mediated HA synthesis is essential for the fetal fibroblasts' enhanced invasion and migration properties. Moreover, IL-10 via an HA-dependent mechanism can recapitulate this aspect of the fetal phenotype in adult fibroblasts, suggesting a novel mechanism of IL-10 in regenerative wound healing.

  5. A novel thiol-modified hyaluronan and elastin-like polypetide composite material for tissue engineering of the nucleus pulposus of the intervertebral disc.

    Science.gov (United States)

    Moss, Isaac L; Gordon, Lyle; Woodhouse, Kimberly A; Whyne, Cari M; Yee, Albert J M

    2011-06-01

    Biomechanical, in vitro, and initial in vivo evaluation of a thiol-modified hyaluronan (TM-HA) and elastin-like polypeptide (ELP) composite hydrogel for nucleus pulposus (NP) tissue engineering. To investigate the utility of a TM-HA and ELP composite material as a potential tissue-engineering scaffold to reconstitute the NP in early degenerative disc disease (DDD) on the basis of both biomechanical and biologic parameters. DDD is a common ailment with enormous medical, psychosocial, and economic ramifications. Only end-stage surgical therapies are currently widely available. A less invasive, early stage therapy may provide a clinically relevant treatment option. TM-HA and ELP were combined in various concentrations and cross-linked using poly (ethylene glycol) diacrylate. Resulting materials were evaluated biomechanically using confined compression to determine biphasic material properties. In vitro cell culture with human intervertebral disc (IVD) cells seeded within TM-HA/ELP scaffolds was analyzed for cell viability and phenotype. The hydrogels' materials were evaluated in an established New Zealand White (NZW) rabbit model of DDD. The addition of ELP to TM-HA-based hydrogels resulted in a stiffer construct, which is less stiff than native NP but has time-dependant loading characteristics that may be desirable when injected into the IVD. In vitro experiments demonstrated 70% cell viability at 3 weeks with apparent maintenance of phenotype on the basis of morphologic and immunohistochemical data. The addition of ELP had a positive desirable biomechanical effect but did not have a significant positive or negative biologic effect on cell activity. The in vivo feasibility study demonstrated favorable material characteristics and biocompatibility for application as a minimally invasive injectable NP supplement. TM-HA-based hydrogels provide a hospitable environment for human IVD cells and have material characteristics, particularly when supplemented with ELPs that

  6. Regeneration of dentin-pulp complex with cementum and periodontal ligament formation using dental bud cells in gelatin-chondroitin-hyaluronan tri-copolymer scaffold in swine.

    Science.gov (United States)

    Kuo, Tzong-Fu; Huang, An-Ting; Chang, Hao-Hueng; Lin, Feng-Huei; Chen, San-Tai; Chen, Rung-Shu; Chou, Cheng-Hung; Lin, Hsin-Chi; Chiang, Han; Chen, Min-Huey

    2008-09-15

    The purpose of this study is to use a tissue engineering approach for tooth regeneration. The swine dental bud cells (DBCs) were isolated from the developing mandibular teeth, expanded in vitro, and cultured onto cylinder scaffold gelatin-chrondroitin-hyaluronan-tri-copolymer (GCHT). After culturing in vitro, the DBCs/GCHT scaffold was autografted back into the original alveolar socket. Hematoxylin and eosin (H&E) staining combined with immunohistochemical staining were applied for identification of regenerated tooth structure. After 36-week post-transplantation, tooth-like structures, including well-organized dentin-pulp complex, cementum, and periodontal ligament, were evident in situ in two of six experimental animals. The size of the tooth structure (1 x 0.5 x 0.5 cm(3) and 0.5 x 0.5 x 0.5 cm(3) size) appeared to be dictated by the size of the GCHT scaffold (1 x 1 x 1.5 cm(3)). The third swine was demonstrated with irregular dentin-bony like calcified tissue about 1 cm in diameter without organized tooth or periodontal ligament formation. The other three swine in the experimental group showed normal bone formation and no tooth regeneration in the transplantation sites. The successful rate of tooth regeneration from DBCs/GCHT scaffolds' was about 33.3%. In the control group, three swine's molar teeth buds were removed without DBCs/GCHT implantation, the other three swine received GCHT scaffold implants without DBCs. After evaluation, no regenerated tooth was found in the transplantation site of the control group. The current results using DBSs/GCHT scaffold autotransplantation suggest a technical breakthrough for tooth regeneration.

  7. Rheology and confocal reflectance microscopy as probes of mechanical properties and structure during collagen and collagen/hyaluronan self-assembly.

    Science.gov (United States)

    Yang, Ya-li; Kaufman, Laura J

    2009-02-18

    In this work, the gelation of three-dimensional collagen and collagen/hyaluronan (HA) composites is studied by time sweep rheology and time lapse confocal reflectance microscopy (CRM). To investigate the complementary nature of these techniques, first collagen gel formation is investigated at concentrations of 0.5, 1.0, and 1.5 mg/mL at 37 degrees C and 32 degrees C. The following parameters are used to describe the self-assembly process in all gels: the crossover time (t(c)), the slope of the growth phase (k(g)), and the arrest time (t(a)). The first two measures are determined by rheology, and the third by CRM. A frequency-independent rheological measure of gelation, t(g), is also measured at 37 degrees C. However, this quantity cannot be straightforwardly determined for gels formed at 32 degrees C, indicating that percolation theory does not fully capture the dynamics of collagen network formation. The effects of collagen concentration and gelation temperature on k(g), t(c), and t(a) as well as on the mechanical properties and structure of these gels both during gelation and at equilibrium are elucidated. Composite collagen/HA gels are also prepared, and their properties are monitored at equilibrium and during gelation at 37 degrees C and 32 degrees C. We show that addition of HA subtly alters mechanical properties and structure of these systems both during the gelation process and at equilibrium. This occurs in a temperature-dependent manner, with the ratio of HA deposited on collagen fibers versus that distributed homogeneously between fibers increasing with decreasing gelation temperature. In addition to providing information on collagen and collagen/HA structure and mechanical properties during gelation, this work shows new ways in which rheology and microscopy can be used complementarily to reveal details of gelation processes.

  8. Selective Targeting and Restrictive Damage for Nonspecific Cells by Pulsed Laser-Activated Hyaluronan-Gold Nanoparticles.

    Science.gov (United States)

    Rau, Lih-Rou; Tsao, Shu-Wei; Liaw, Jiunn-Woei; Tsai, Shiao-Wen

    2016-08-08

    Herein, we describe an approach that immobilizes low-molecular-weight hyaluronic acid (low-MW HA) on the surface of gold nanoparticles (GNPs), which can serve as a cellular probe and photodamage media, to evaluate the selectivity and efficiency of HA-based GNPs (HGNPs) as a mediator of laser-induced photothermal cell damage. In addition, it is known that solid tumors contain a higher content of low-MW HA than normal tissues. Thus, we used low-MW HA rather than high-MW HA used in other studies. In the present study, we conjugated low-MW HA, which is a linear polysaccharide with a disaccharide repeat unit, to prevent a reduction of the ligand-receptor binding efficiency in contrast to the conjugation of protein or peptides, which have unique three-dimensional structures. Three cell lines-MDA-MB-435 S (with CD44), MDA-MB-453 and NIH/3T3 (both are without CD44)-were investigated in the study, and qualitative observations were conducted by dark-field microscopy and laser scanning confocal microscopy (LSCM). In addition, quantitative measurements calculated using inductively coupled plasma emissions were taken for comparison. Our results showed that within the same treatment time, the uptake dosage of HGNPs by the MDA-MB-435 S cells was higher than that by the MDA-MB-453 and NIH 3T3 cells. Meanwhile, HGNPs uptake by the untreated MDA-MB-435 S cells was higher than that of MDA-MB-435 S cells with CD44 blocked by antibodies or silencing CD44 expression. This result implies that receptor-mediated endocytosis can enhance the cellular uptake of HGNPs. In addition, when exposed to a low-power pulsed laser, the former cell morphologies showed a more laser-induced giant plasma membrane vesicles (GPMV) than the latter morphologies. Therefore, this study utilized the specific photothermal property of HA-modified GNPs with laser-induced blebs to create a possible new method for medical applications.

  9. Response to injection of the navicular bursa with corticosteroid and hyaluronan following high-field magnetic resonance imaging in horses with signs of navicular syndrome: 101 cases (2000-2008).

    Science.gov (United States)

    Marsh, Chad A; Schneider, Robert K; Sampson, Sarah N; Roberts, Greg D

    2012-11-15

    To determine treatment outcome on the basis of pathological changes identified on MRI and lameness duration in horses with navicular syndrome that underwent injection of corticosteroid and hyaluronan into the navicular bursa. Retrospective case series. 101 horses with navicular syndrome. Medical records of horses with signs of navicular syndrome evaluated between January 2000 and December 2008 were reviewed. Data on signalment, use of the horse, history, affected limbs, duration of lameness, findings on lameness examination, radiographic findings, MRI findings, treatment, and outcome were collected from the medical records. Follow-up information was obtained a minimum of 10 months after navicular bursa injection. Following navicular bursa injection, 76 of 101 (75%) horses returned to their intended use for a mean of 9.66 months, and 35 (35%) were sound at follow-up. Horses that had been lame for horses that had a longer lameness history. Horses with primary deep digital flexor (DDF) tendonitis responded best to navicular bursa injection with rest and rehabilitation, followed by horses with navicular bursitis and horses with DDF tendonitis and adhesions to the collateral sesamoidean ligament of the distal sesamoid (navicular) bone. Horses with scar tissue in the proximal portion of the navicular bursa, adhesions from the navicular bone to the DDF tendon, or multiple abnormalities did not respond as well to treatment. Response to navicular bursa injection with corticosteroid and hyaluronan in horses with navicular syndrome was dependent on the disease process detected on MRI and duration of lameness.

  10. Efficacy of intra-articular hyaluronan (Synvisc® for the treatment of osteoarthritis affecting the first metatarsophalangeal joint of the foot (hallux limitus: study protocol for a randomised placebo controlled trial

    Directory of Open Access Journals (Sweden)

    Landorf Karl B

    2009-01-01

    Full Text Available Abstract Background Osteoarthritis of the first metatarsophalangeal joint (MPJ of the foot, termed hallux limitus, is common and painful. Numerous non-surgical interventions have been proposed for this disorder, however there is limited evidence for their efficacy. Intra-articular injections of hyaluronan have shown beneficial effects in case-series and clinical trials for the treatment of osteoarthritis of the first metatarsophalangeal joint. However, no study has evaluated the efficacy of this form of treatment using a randomised placebo controlled trial. This article describes the design of a randomised placebo controlled trial to evaluate the efficacy of intra-articular hyaluronan (Synvisc® to reduce pain and improve function in people with hallux limitus. Methods One hundred and fifty community-dwelling men and women aged 18 years and over with hallux limitus (who satisfy inclusion and exclusion criteria will be recruited. Participants will be randomised, using a computer-generated random number sequence, to receive a single intra-articular injection of up to 1 ml hyaluronan (Synvisc® or sterile saline (placebo into the first MPJ. The injections will be performed by an interventional radiologist using fluoroscopy to ensure accurate deposition of the hyaluronan in the joint. Participants will be given the option of a second and final intra-articular injection (of Synvisc® or sterile saline according to the treatment group they are in either 1 or 3 months post-treatment if there is no improvement in pain and the participant has not experienced severe adverse effects after the first injection. The primary outcome measures will be the pain and function subscales of the Foot Health Status Questionnaire. The secondary outcome measures will be pain at the first MPJ (during walking and at rest, stiffness at the first MPJ, passive non-weightbearing dorsiflexion of the first MPJ, plantar flexion strength of the toe-flexors of the hallux, global

  11. Opioid Receptors.

    Science.gov (United States)

    Stein, Christoph

    2016-01-01

    Opioids are the oldest and most potent drugs for the treatment of severe pain. Their clinical application is undisputed in acute (e.g., postoperative) and cancer pain, but their long-term use in chronic pain has met increasing scrutiny. This article reviews mechanisms underlying opioid analgesia and other opioid actions. It discusses the structure, function, and plasticity of opioid receptors; the central and peripheral sites of analgesic actions and side effects; endogenous and exogenous opioid receptor ligands; and conventional and novel opioid compounds. Challenging clinical situations, such as the tension between chronic pain and addiction, are also illustrated.

  12. Hyaluronidases and hyaluronan synthases expression is inversely correlated with malignancy in lung/bronchial pre-neoplastic and neoplastic lesions, affecting prognosis

    Directory of Open Access Journals (Sweden)

    V.K. de Sá

    2015-11-01

    Full Text Available We collected a series of 136 lung/bronchial and 56 matched lung parenchyma tissue samples from patients who underwent lung/bronchial biopsies and presented invasive carcinoma after lung surgery. The lung/bronchial samples included basal cell hyperplasia, squamous metaplasia, moderate dysplasia, adenomatous hyperplasia, severe dysplasia, squamous cell carcinoma and adenocarcinoma. Matched lung parenchyma tissue samples included 25 squamous cell carcinomas and 31 adenocarcinomas. Immunohistochemistry was performed to analyze for the distribution of hyaluronidase (Hyal-1 and −3, and hyaluronan synthases (HAS-1, −2, and −3. Hyal-1 showed significantly higher expression in basal cell hyperplasia than in moderate dysplasia (P=0.01, atypical adenomatous hyperplasia (P=0.0001, or severe dysplasia (P=0.03. Lower expression of Hyal-3 was found in atypical adenomatous hyperplasia than in basal cell hyperplasia (P=0.01 or moderate dysplasia (P=0.02. HAS-2 was significantly higher in severe dysplasia (P=0.002 and in squamous metaplasia (P=0.04 compared with basal cell hyperplasia. HAS-3 was significantly expressed in basal cell hyperplasia compared with atypical adenomatous hyperplasia (P=0.05 and severe dysplasia (P=0.02. Lower expression of HAS-3 was found in severe dysplasia compared with squamous metaplasia (P=0.01 and moderate dysplasia (P=0.01. Epithelial Hyal-1 and −3 and HAS-1, −2, and −3 expressions were significantly higher in pre-neoplastic lesions than in neoplastic lesions. Comparative Cox multivariate analysis controlled by N stage and histologic tumor type showed that patients with high HAS-3 expression in pre-neoplastic cells obtained by lung/bronchial biopsy presented a significantly higher risk of death (HR=1.19; P=0.04. We concluded that localization of Hyal and HAS in lung/bronchial pre-neoplastic and neoplastic lesions was inversely related to malignancy, which implied that visualizing these factors could be a useful

  13. Development of drug loaded nanoparticles for tumor targeting. Part 2: Enhancement of tumor penetration through receptor mediated transcytosis in 3D tumor models

    Science.gov (United States)

    El-Dakdouki, Mohammad H.; Puré, Ellen; Huang, Xuefei

    2013-04-01

    We report that receptor mediated transcytosis can be utilized to facilitate tumor penetration by drug loaded nanoparticles (NPs). We synthesized hyaluronan (HA) coated silica nanoparticles (SNPs) containing a highly fluorescent core to target CD44 expressed on the cancer cell surface. Although prior studies have primarily focused on CD44 mediated endocytosis to facilitate cellular uptake of HA-NPs by cancer cells, we discovered that, once internalized, the HA-SNPs could be transported out of the cells with their cargo. The exported NPs could be taken up by neighboring cells. This enabled the HA-SNPs to penetrate deeper inside tumors and reach a much greater number of tumor cells in 3D tumor models, presumably through tandem cycles of CD44 mediated endocytosis and exocytosis. When doxorubicin (DOX) was loaded onto the NPs, better penetration of multilayered tumor cells was observed with much improved cytotoxicities against both drug sensitive and drug resistant cancer spheroids compared to the free drug. Thus, targeting receptors such as CD44 that can readily undergo recycling between the cell surface and interior of the cells can become a useful strategy to enhance the tumor penetration potential of NPs and the efficiency of drug delivery through receptor mediated transcytosis.We report that receptor mediated transcytosis can be utilized to facilitate tumor penetration by drug loaded nanoparticles (NPs). We synthesized hyaluronan (HA) coated silica nanoparticles (SNPs) containing a highly fluorescent core to target CD44 expressed on the cancer cell surface. Although prior studies have primarily focused on CD44 mediated endocytosis to facilitate cellular uptake of HA-NPs by cancer cells, we discovered that, once internalized, the HA-SNPs could be transported out of the cells with their cargo. The exported NPs could be taken up by neighboring cells. This enabled the HA-SNPs to penetrate deeper inside tumors and reach a much greater number of tumor cells in 3D tumor

  14. Peripheral-type benzodiazepine receptor levels correlate with the ability of human breast cancer MDA-MB-231 cell line to grow in SCID mice.

    Science.gov (United States)

    Hardwick, M; Rone, J; Han, Z; Haddad, B; Papadopoulos, V

    2001-11-01

    MDA-MB-231 (MDA-231) human breast cancer cells have a high proliferation rate, lack the estrogen receptor, express the intermediate filament vimentin, the hyaluronan receptor CD44, and are able to form tumors in nude mice. The MDA-231 cell line has been used in our laboratory to examine the role of the peripheral-type benzodiazepine receptor (PBR) in the progression of cancer. During these studies 2 populations of MDA-231 cells were subcloned based on the levels of PBR. The subclones proliferated at approximately the same rate, lacked the estrogen receptor, expressed vimentin and CD44, and had the same in vitro chemoinvasive and chemotactic potential. Both restriction fragment length polymorphism and comparative genomic hybridization analyses of genomic DNA from these cells indicated that both subclones are of the same genetic lineage. Only the subclone with high PBR levels, however, was able to form tumors when injected in SCID mice. These data suggest that the ability of MDA-231 cells to form tumors in vivo may depend on the amount of PBR present in the cells.

  15. The androgen receptor and estrogen receptor

    NARCIS (Netherlands)

    Oosterkamp, H.M.; Bernards, R.A.

    2002-01-01

    The androgen receptor (AR) and the estrogen receptors (ER) are members of the nuclear receptor (NR) family. These NRs are distinguished from the other transcription factors by their ability to control gene expression upon ligand binding (steroids, retinoids, thyroid hormone, vitamin D, fatty acids,

  16. PDGF-BB-mediated activation of p42(MAPK) is independent of PDGF beta-receptor tyrosine phosphorylation.

    Science.gov (United States)

    Cartel, N J; Liu, J; Wang, J; Post, M

    2001-10-01

    Herein, we investigated the activity of mitogen-activated protein kinase (MAPK), a key component of downstream signaling events, which is activated subsequent to platelet-derived growth factor (PDGF)-BB stimulation. Specifically, p42(MAPK) activity peaked 60 min after addition of PDGF-BB, declined thereafter, and was determined not to be a direct or necessary component of glycosaminoglycan (GAG) synthesis. PDGF-BB also activated MAPK kinase 2 (MAPKK2) but had no effect on MAPKK1 and Raf-1 activity. Chemical inhibition of Janus kinase, phosphatidylinositol 3-kinase, Src kinase, or tyrosine phosphorylation inhibition of the PDGF beta-receptor (PDGFR-beta) did not abrogate PDGF-BB-induced p42(MAPK) activation or its threonine or tyrosine phosphorylation. A dominant negative cytoplasmic receptor for hyaluronan-mediated motility variant 4 (RHAMMv4), a regulator of MAPKK-MAPK interaction and activation, did not inhibit PDGF-BB-induced p42(MAPK) activation nor did a construct expressing PDGFR-beta with cytoplasmic tyrosines mutated to phenylalanine. However, overexpression of a dominant negative PDGFR-beta lacking the cytoplasmic signaling domain abrogated p42(MAPK) activity. These results suggest that PDGF-BB-mediated activation of p42(MAPK) requires the PDGFR-beta but is independent of its tyrosine phosphorylation.

  17. New model of in-situ xenograft lymphangiogenesis by a human colonic adenocarcinoma cell line in nude mice.

    Science.gov (United States)

    Sun, Jian-Jun; Jing, Wei; Ni, Yan-Yan; Yuan, Xiao-Jian; Zhou, Hai-Hua; Fan, Yue-Zu

    2012-01-01

    To explore a new model of in-situ xenograft lymphangiogenesis of human colonic adenocarcinomas in nude mice. On the basis of establishing subcutaneous xenograft lymphangiogenesis model of human colonic adenocarcinoms, in-situ xenografts were established through the in situ growth of the HT-29 human colonic adenocarcinoma cell line in nude mice. The numbers of lymphangiogenic microvessels, the expression of lymphatic endothelial cell markers lymphatic vessel endothelial hyaloronic acid receptor-1 (LYVE-1), D2-40 and the lymphatic endothelial growth factors vascular endothelial growth factor-C (VEGF-C), -D (VEGF-D) and receptor-3 (VEGFR-3) were compared by immunohistochemical staining, Western bolt and quantitative RT-PCR in xenograft in-situ models. Some microlymphatics with thin walls, large and irregular or collapsed cavities and increased LMVD, with strong positive of LYVE-1, D2-40 in immunohistochemistry, were observed, identical with the morphological characteristics of lymphatic vessels and capillaries. Expression of LYVE-1 and D2-40 proteins and mRNAs were significantly higher in xenografts in-situ than in the negative control group (both Pconformity with the signal regulation of the VEGF-C,-D/VEGFR-3 axis of tumor lymphangiogenesis. In-situ xenografts of a human colonic adenocarcinoma cell line demonstrate tumor lymphangiogenesis. This novel in-situ animal model should be useful for further studying mechanisms of lymph node metastasis, drug intervention and anti-metastasis therapy in colorectal cancer.

  18. GLP-1 Receptor Agonists

    Science.gov (United States)

    ... in Balance › GLP-1 Receptor Agonists Fact Sheet GLP-1 Receptor Agonists May, 2012 Download PDFs English Espanol Editors Silvio ... are too high or too low. What are GLP-1 receptor agonist medicines? GLP-1 receptor agonist medicines, also called ...

  19. 玻璃酸钠对老年膝关节炎患者本体感觉的影响%Effect of intra-articular injection of hyaluronan on proprioception of the knee joint in gerontal patients with osteoarthritis

    Institute of Scientific and Technical Information of China (English)

    潘哲尔; 张挺; 刘扬波; 张纯武; 李驰; 朱雄白

    2011-01-01

    Objective To investigate the short-term effects of intra-articular injection of hyaluronan on proprioception of the knee in gerontal patients with osteoarthritis (OA). Methods The 53 gerontal patients were included in this study. The study included treatment group (n=35) and the placebo group (n=18). Hyaluronan was intra-articularly injected into both knees of the subjects in treatment group, whereas physiological saline was intra-articularly injected in the placebo group. Proprioception test was performed, and Western Ontario and McMaster Universities(WOMAC) scales were used to evaluate pain and physical function. Results Statistical analysis was performed on 100 knees of 50 patients who completed the trial. Compared with the placebo group,the average absolute angular error (AAAE) value in the treatment group was detected to be statistically lower one week after the 4th injection (1.8±0.9 vs.2.9±1.1,t=2.42,P=0.02),and WOMAC was lower in the treatment group after one week (8.7±3.1 vs.11.5±4.0, t=0.73,P<0.05). Conclusions Intra-articular injection of hyaluronan in gerontal patients with knee OA leads to a short-term increase in proprioception, and significant improvement in the functional conditions of patients.%目的 研究关节内注射玻璃酸钠后对老年膝骨关节炎患者膝关节本体感觉的影响.方法 共53例老年患者入选该研究.受试者被随机分为治疗组(35例)和安慰剂组(18例).治疗组患者行双侧膝关节玻璃酸钠(阿尔治)关节内注射,安慰剂组则予双侧膝关节注射生理盐水.测量膝关节本体感觉,西方安大略和麦克马斯特大学(WOMAC)骨关节炎指数评分表用于评估膝关节疼痛和功能改善情况.结果 共50例患者100个膝关节进行了评估,平均绝对角误差值在第4次注射后1周,治疗组明显低于安慰剂组,分别为(1.8±0.9)分和(2.9±1.1)分(t=2.42,P=0.02);治疗组WOMAC积分在注射玻璃酸钠1周后开始明显下降,治疗组和

  20. Co-cultivation of keratinocyte-human mesenchymal stem cell (hMSC) on sericin loaded electrospun nanofibrous composite scaffold (cationic gelatin/hyaluronan/chondroitin sulfate) stimulates epithelial differentiation in hMSCs: In vitro study.

    Science.gov (United States)

    Bhowmick, Sirsendu; Scharnweber, Dieter; Koul, Veena

    2016-05-01

    Fortifying the scaffold with bioactive molecules and glycosaminoglycans (GAGs), is an efficient way to design new generation tissue engineered biomaterials. In this study, we evaluated the synergistic effect of electrospun nanofibrous composite scaffold (cationic gelatin/hyaluronan/chondroitin sulfate) loaded with sericin and, contact co-culture of human mesenchymal stem cells (hMSCs)-keratinocytes on hMSCs' differentiation towards epithelial lineage. Cationic gelatin is prepared with one step novel synthesis process by grafting quaternary ammonium salts to the backbone of gelatin. Release kinetics studies showed that Fickian diffusion is the major release mechanism for both GAGs and sericin/gelatin. In vitro biocompatibility of the electrospun scaffold was evaluated in terms of LDH and DNA quantification assay on human foreskin fibroblast, human keratinocyte and hMSC. Significant proliferation (∼ 4-6 fold) was detected after culturing all three cell on the electrospun scaffold containing sericin. After 5 days of contact co-culture, results revealed that electrospun scaffold containing sericin promote epithelial differentiation of hMSC in terms of several protein markers (keratin 14, ΔNp63α and Pan-cytokeratin) and gene expression of some dermal proteins (keratin 14, ΔNp63α). Findings of this study will foster the progress of current skin tissue engineering scaffolds by understanding the skin regeneration and wound healing process.

  1. Acetylcholine receptor antibody

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/003576.htm Acetylcholine receptor antibody To use the sharing features on this page, please enable JavaScript. Acetylcholine receptor antibody is a protein found in the blood ...

  2. Androgen receptor abnormalities

    NARCIS (Netherlands)

    A.O. Brinkmann (Albert); G.G.J.M. Kuiper (George); C. Ris-Stalpers (Carolyn); H.C.J. van Rooij (Henri); G. Romalo (G.); G. Trifiro (Gianluca); E. Mulder (Eppo); L. Pinsky (L.); H.U. Schweikert (H.); J. Trapman (Jan)

    1991-01-01

    markdownabstract__Abstract__ The human androgen receptor is a member of the superfamily of steroid hormone receptors. Proper functioning of this protein is a prerequisite for normal male sexual differentiation and development. The cloning of the human androgen receptor cDNA and the elucidation of t

  3. Mammalian Sweet Taste Receptors

    National Research Council Canada - National Science Library

    Nelson, Greg; Hoon, Mark A; Chandrashekar, Jayaram; Zhang, Yifeng; Ryba, Nicholas J.P; Zuker, Charles S

    2001-01-01

    ... and information coding, and have focused on the isolation and characterization of genes encoding sweet and bitter taste receptors. The identification of taste receptors generates powerful molecular tools to investigate not only the function of taste receptor cells, but also the logic of taste coding. For example, defining the size and diversity of the re...

  4. Overexpression of CD44 accompanies acquired tamoxifen resistance in MCF7 cells and augments their sensitivity to the stromal factors, heregulin and hyaluronan

    Directory of Open Access Journals (Sweden)

    Hiscox Stephen

    2012-10-01

    Full Text Available Abstract Background Acquired resistance to endocrine therapy in breast cancer is a significant problem with relapse being associated with local and/or regional recurrence and frequent distant metastases. Breast cancer cell models reveal that endocrine resistance is accompanied by a gain in aggressive behaviour driven in part through altered growth factor receptor signalling, particularly involving erbB family receptors. Recently we identified that CD44, a transmembrane cell adhesion receptor known to interact with growth factor receptors, is upregulated in tamoxifen-resistant (TamR MCF7 breast cancer cells. The purpose of this study was to explore the consequences of CD44 upregulation in an MCF7 cell model of acquired tamoxifen resistance, specifically with respect to the hypothesis that CD44 may influence erbB activity to promote an adverse phenotype. Methods CD44 expression in MCF7 and TamR cells was assessed by RT-PCR, Western blotting and immunocytochemistry. Immunofluorescence and immunoprecipitation studies revealed CD44-erbB associations. TamR cells (± siRNA-mediated CD44 suppression or MCF7 cells (± transfection with the CD44 gene were treated with the CD44 ligand, hyaluronon (HA, or heregulin and their in vitro growth (MTT, migration (Boyden chamber and wound healing and invasion (Matrigel transwell migration determined. erbB signalling was assessed using Western blotting. The effect of HA on erbB family dimerisation in TamR cells was determined by immunoprecipitation in the presence or absence of CD44 siRNA. Results TamR cells overexpressed CD44 where it was seen to associate with erbB2 at the cell surface. siRNA-mediated suppression of CD44 in TamR cells significantly attenuated their response to heregulin, inhibiting heregulin-induced cell migration and invasion. Furthermore, TamR cells exhibited enhanced sensitivity to HA, with HA treatment resulting in modulation of erbB dimerisation, ligand-independent activation of erbB2

  5. [Melatonin receptor agonist].

    Science.gov (United States)

    Uchiyama, Makoto

    2015-06-01

    Melatonin is a hormone secreted by the pineal gland and is involved in the regulation of human sleep-wake cycle and circadian rhythms. The melatonin MT1 and MT2 receptors located in the suprachiasmatic nucleus in the hypothalamus play a pivotal role in the sleep-wake regulation. Based on the fact that MT1 receptors are involved in human sleep onset process, melatonin receptor agonists have been developed to treat insomnia. In this article, we first reviewed functions of melatonin receptors with special reference to MT1 and MT2, and properties and clinical application of melatonin receptor agonists as hypnotics.

  6. Dopamine receptors and hypertension.

    Science.gov (United States)

    Banday, Anees Ahmad; Lokhandwala, Mustafa F

    2008-08-01

    Dopamine plays an important role in regulating renal function and blood pressure. Dopamine synthesis and dopamine receptor subtypes have been shown in the kidney. Dopamine acts via cell surface receptors coupled to G proteins; the receptors are classified via pharmacologic and molecular cloning studies into two families, D1-like and D2-like. Two D1-like receptors cloned in mammals, the D1 and D5 receptors (D1A and D1B in rodents), are linked to adenylyl cyclase stimulation. Three D2-like receptors (D2, D3, and D4) have been cloned and are linked mainly to adenylyl cyclase inhibition. Activation of D1-like receptors on the proximal tubules inhibits tubular sodium reabsorption by inhibiting Na/H-exchanger and Na/K-adenosine triphosphatase activity. Reports exist of defective renal dopamine production and/or dopamine receptor function in human primary hypertension and in genetic models of animal hypertension. In humans with essential hypertension, renal dopamine production in response to sodium loading is often impaired and may contribute to hypertension. A primary defect in D1-like receptors and an altered signaling system in proximal tubules may reduce dopamine-mediated effects on renal sodium excretion. The molecular basis for dopamine receptor dysfunction in hypertension is being investigated, and may involve an abnormal posttranslational modification of the dopamine receptor.

  7. GABA receptor imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Doo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2007-04-15

    GABA is primary an inhibitory neurotransmitter that is localized in inhibitory interneurons. GABA is released from presynaptic terminals and functions by binding to GABA receptors. There are two types of GABA receptors, GABA{sub A}-receptor that allows chloride to pass through a ligand gated ion channel and GABA{sub B}-receptor that uses G-proteins for signaling. The GABA{sub A}-receptor has a GABA binding site as well as a benzodiazepine binding sites, which modulate GABA{sub A}-receptor function. Benzodiazepine GABAA receptor imaging can be accomplished by radiolabeling derivates that activates benzodiazepine binding sites. There has been much research on flumazenil (FMZ) labeled with {sup 11}C-FMZ, a benzodiazepine derivate that is a selective, reversible antagonist to GABAA receptors. Recently, {sup 18}F-fluoroflumazenil (FFMZ) has been developed to overcome {sup 11}C's short half-life. {sup 18}F-FFMZ shows high selective affinity and good pharmacodynamics, and is a promising PET agent with better central benzodiazepine receptor imaging capabilities. In an epileptic focus, because the GABA/benzodiazepine receptor amount is decreased, using '1{sup 1}C-FMZ PET instead of {sup 18}F-FDG, PET, restrict the foci better and may also help find lesions better than high resolution MR. GABA{sub A} receptors are widely distributed in the cerebral cortex, and can be used as an viable neuronal marker. Therefore it can be used as a neuronal cell viability marker in cerebral ischemia. Also, GABA-receptors decrease in areas where neuronal plasticity develops, therefore, GABA imaging can be used to evaluate plasticity. Besides these usages, GABA receptors are related with psychological diseases, especially depression and schizophrenia as well as cerebral palsy, a motor-related disorder, so further in-depth studies are needed for these areas.

  8. Effect of macrophages with different activated phenotypes on tumor growth, lymphangiogenesis and lymph node metastasis in mice bearing Lewis lung carcinoma%不同活化表型的巨噬细胞对小鼠肺癌移植瘤生长、淋巴管生成和淋巴结转移的影响

    Institute of Scientific and Technical Information of China (English)

    章必成; 赵勇; 王俊; 郭燕; 饶智国; 高建飞

    2008-01-01

    目的:探讨不同活化表型的巨噬细胞对小鼠Lewis肺癌(Lewis lung carcinoma,LLC)移植瘤生长、淋巴管生成和淋巴结转移的影响.方法:将活化的巨噬细胞与LLC细胞混合后注射至小鼠颈部背侧皮下,建立移植瘤模型,分为4组:空白对照组,经典活化的巨噬细胞(classically activated macrophages,caMphi)组,替代性活化的巨噬细胞(alternatively activated macro-phages,aaMphi)组和RAW264.7巨噬细胞组.每组10只小鼠,观察移植瘤生长情况.d 28时杀死小鼠,HE染色检测淋巴结和远处器官转移情况,免疫组织化学法检测并计数移植瘤淋巴管内皮细胞透明质酸受体-1(lymphatic vessel endothelial hyaluro-nan receptor-1,LYVE-1)阳性淋巴管密度(lymphatic vessel density,LVD).同时另取40只小鼠随机分为上述4组,观察其生存时间并计算生存率.结果:与空白对照组比较,aaMphi组和RAW264.7组移植瘤生长速度较快,淋巴结转移数和双肺转移结节数较多(P0.05).结论:aaMphi能够促进LLC移植瘤生长、淋巴管生成、淋巴结和肺转移,并降低荷瘤小鼠生存率.在与LLC一起形成移植瘤的过程中,未经处理的巨噬细胞可以朝着aaMphi的方向极化.

  9. Doxorubicin-Hyaluronan Conjugated Super-Paramagnetic Iron Oxide Nanoparticles (DOX-HA-SPION) Enhanced Cytoplasmic Uptake of Doxorubicin and Modulated Apoptosis, IL-6 Release and NF-kappaB Activity in Human MDA-MB-231 Breast Cancer Cells.

    Science.gov (United States)

    Vyas, Dinesh; Lopez-Hisijos, Nicolas; Gandhi, Sulakshana; El-Dakdouki, M; Basson, Marc D; Walsh, Mary F; Huang, X; Vyas, Arpita K; Chaturvedi, Lakshmi S

    2015-09-01

    Triple negative breast cancer exhibit increased IL-6 expression compared with matched healthy breast tissue and a strong link between inflammation and cancer progression and metastasis has been reported. We investigated whether doxorubicin-hyaluronan-super-paramagnetic iron oxide nanoparticles (DOX-HA-SPION) would show greater therapeutic efficacy in human triple negative breast cancer cells (TNBC) MDA-MB-231, as was recently shown in drug-sensitive and multi-drug-resistant ovarian cancer cells. Therefore, we measured cellular DOX uptake via confocal microscopy; observed morphologic changes: mitochondrial and nuclear changes with electron microscopy, and quantitated apoptosis using FACS analysis after Annexin V and PI staining in MDA-MB-231 cells treated with either DOX alone or DOX-HA-SPION. We also measured both proinflammatory and anti-inflammatory cytokines; IL-6, IL-10 respectively and also measured nitrate levels in the conditioned medium by ELISA. Inaddition, NF-κB activity was measured by luciferase assay. Confocal microscopy demonstrated greater cytoplasmic uptake of DOX-HA-SPION than free DOX. We also demonstrated reduction of Vimentin with DOX-HA-SPION which is significantly less than both control and DOX. DOX-HA-SPION enhanced apoptosis and significantly down regulated both pro-inflammatory mediators IL-6 and NF-κB in comparison to DOX alone. The secretion levels of anti-inflammatory mediators IL-10 and nitrate was not decreased in the DOX or DOX-HA-SPION treatment groups. Our data suggest that DOX-HA-SPION nanomedicine-based drug delivery could have promising potential in treating metastasized and chemoresistant breast cancer by enhancing the drug efficacy and minimizing off-target effects.

  10. Chicken NK cell receptors.

    Science.gov (United States)

    Straub, Christian; Neulen, Marie-Luise; Sperling, Beatrice; Windau, Katharina; Zechmann, Maria; Jansen, Christine A; Viertlboeck, Birgit C; Göbel, Thomas W

    2013-11-01

    Natural killer cells are innate immune cells that destroy virally infected or transformed cells. They recognize these altered cells by a plethora of diverse receptors and thereby differ from other lymphocytes that use clonally distributed antigen receptors. To date, several receptor families that play a role in either activating or inhibiting NK cells have been identified in mammals. In the chicken, NK cells have been functionally and morphologically defined, however, a conclusive analysis of receptors involved in NK cell mediated functions has not been available. This is partly due to the low frequencies of NK cells in blood or spleen that has hampered their intensive characterization. Here we will review recent progress regarding the diverse NK cell receptor families, with special emphasis on novel families identified in the chicken genome with potential as chicken NK cell receptors. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Novel cannabinoid receptors

    OpenAIRE

    Brown, A J

    2007-01-01

    Cannabinoids have numerous physiological effects. In the years since the molecular identification of the G protein-coupled receptors CB1 and CB2, the ion channel TRPV1, and their corresponding endogenous ligand systems, many cannabinoid-evoked actions have been shown conclusively to be mediated by one of these specific receptor targets. However, there remain several examples where these classical cannabinoid receptors do not explain observed pharmacology. Studies using mice genetically delete...

  12. Therapeutic androgen receptor ligands

    OpenAIRE

    Allan, George F.; Sui, Zhihua

    2003-01-01

    In the past several years, the concept of tissue-selective nuclear receptor ligands has emerged. This concept has come to fruition with estrogens, with the successful marketing of drugs such as raloxifene. The discovery of raloxifene and other selective estrogen receptor modulators (SERMs) has raised the possibility of generating selective compounds for other pathways, including androgens (that is, selective androgen receptor modulators, or SARMs).

  13. AMPA receptor ligands

    DEFF Research Database (Denmark)

    Strømgaard, Kristian; Mellor, Ian

    2004-01-01

    Alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors (AMPAR), subtype of the ionotropic glutamate receptors (IGRs), mediate fast synaptic transmission in the central nervous system (CNS), and are involved in many neurological disorders, as well as being a key player in the f......Alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors (AMPAR), subtype of the ionotropic glutamate receptors (IGRs), mediate fast synaptic transmission in the central nervous system (CNS), and are involved in many neurological disorders, as well as being a key player...

  14. Biomaterial-enabled delivery of SDF-1α at the ventral side of breast cancer cells reveals a crosstalk between cell receptors to promote the invasive phenotype.

    Science.gov (United States)

    Liu, Xi Qiu; Fourel, Laure; Dalonneau, Fabien; Sadir, Rabia; Leal, Salome; Lortat-Jacob, Hugues; Weidenhaupt, Marianne; Albiges-Rizo, Corinne; Picart, Catherine

    2017-05-01

    The SDF-1α chemokine (CXCL12) is a potent bioactive chemoattractant known to be involved in hematopoietic stem cell homing and cancer progression. The associated SDF-1α/CXCR4 receptor signaling is a hallmark of aggressive tumors, which can metastasize to distant sites such as lymph nodes, lung and bone. Here, we engineered a biomimetic tumoral niche made of a thin and soft polyelectrolyte film that can retain SDF-1α to present it, in a spatially-controlled manner, at the ventral side of the breast cancer cells. Matrix-bound SDF-1α but not soluble SDF-1α induced a striking increase in cell spreading and migration in a serum-containing medium, which was associated with the formation of lamellipodia and filopodia in MDA-MB231 cells and specifically mediated by CXCR4. Other Knockdown and inhibition experiments revealed that CD44, the major hyaluronan receptor, acted in concert, via a spatial coincidence, to drive a specific matrix-bound SDFα-induced cell response associated with ERK signaling. In contrast, the β1 integrin adhesion receptor played only a minor role on cell polarity. The CXCR4/CD44 mediated cellular response to matrix-bound SDF-1α involved the Rac1 RhoGTPase and was sustained solely in the presence of matrix-bound SDFα, in contrast with the transient signaling observed in response to soluble SDF-1α. Our results highlight that a biomimetic tumoral niche enables to reveal potent cellular effects and so far hidden molecular mechanisms underlying the breast cancer response to chemokines. These results open new insights for the design of future innovative therapies in metastatic cancers, by inhibiting CXCR4-mediated signaling in the tumoral niche via dual targeting of receptors (CXCR4 and CD44) or of associated signaling molecules (CXCR4 and Rac1).

  15. Signaling of Prostaglandin E Receptors, EP3 and EP4 Facilitates Wound Healing and Lymphangiogenesis with Enhanced Recruitment of M2 Macrophages in Mice.

    Science.gov (United States)

    Hosono, Kanako; Isonaka, Risa; Kawakami, Tadashi; Narumiya, Shuh; Majima, Masataka

    2016-01-01

    Lymphangiogenesis plays an important role in homeostasis, metabolism, and immunity, and also occurs during wound-healing. Here, we examined the roles of prostaglandin E2 (PGE2) receptor (EP) signaling in enhancement of lymphangiogenesis in wound healing processes. The hole-punch was made in the ears of male C57BL/6 mice using a metal ear punch. Healing process and lymphangiogenesis together with macrophage recruitment were analyzed in EP knockout mice. Lymphangiogenesis was up-regulated in the granulation tissues at the margins of punched-hole wounds in mouse ears, and this increase was accompanied by increased expression levels of COX-2 and microsomal prostaglandin E synthase-1. Administration of celecoxib, a COX-2 inhibitor, suppressed lymphangiogenesis in the granulation tissues and reduced the induction of the pro-lymphangiogenic factors, vascular endothelial growth factor (VEGF) -C and VEGF-D. Topical applications of selective EP receptor agonists enhanced the expressions of lymphatic vessel endothelial hyaluronan receptor-1 and VEGF receptor-3. The wound-healing processes and recruitment of CD11b-positive macrophages, which produced VEGF-C and VEGF-D, were suppressed under COX-2 inhibition. Mice lacking either EP3 or EP4 exhibited reduced wound-healing, lymphangiogenesis and recruitment of M2 macrophages, compared with wild type mice. Proliferation of cultured human lymphatic endothelial cells was not detected under PGE2 stimulation. Lymphangiogenesis and recruitment of M2 macrophages that produced VEGF-C/D were suppressed in mice treated with a COX-2 inhibitor or lacking either EP3 or EP4 during wound healing. COX-2 and EP3/EP4 signaling may be novel targets to control lymphangiogenesis in vivo.

  16. Signaling of Prostaglandin E Receptors, EP3 and EP4 Facilitates Wound Healing and Lymphangiogenesis with Enhanced Recruitment of M2 Macrophages in Mice

    Science.gov (United States)

    Hosono, Kanako; Isonaka, Risa; Kawakami, Tadashi; Narumiya, Shuh; Majima, Masataka

    2016-01-01

    Lymphangiogenesis plays an important role in homeostasis, metabolism, and immunity, and also occurs during wound-healing. Here, we examined the roles of prostaglandin E2 (PGE2) receptor (EP) signaling in enhancement of lymphangiogenesis in wound healing processes. The hole-punch was made in the ears of male C57BL/6 mice using a metal ear punch. Healing process and lymphangiogenesis together with macrophage recruitment were analyzed in EP knockout mice. Lymphangiogenesis was up-regulated in the granulation tissues at the margins of punched-hole wounds in mouse ears, and this increase was accompanied by increased expression levels of COX-2 and microsomal prostaglandin E synthase-1. Administration of celecoxib, a COX-2 inhibitor, suppressed lymphangiogenesis in the granulation tissues and reduced the induction of the pro-lymphangiogenic factors, vascular endothelial growth factor (VEGF) -C and VEGF-D. Topical applications of selective EP receptor agonists enhanced the expressions of lymphatic vessel endothelial hyaluronan receptor-1 and VEGF receptor-3. The wound-healing processes and recruitment of CD11b-positive macrophages, which produced VEGF-C and VEGF-D, were suppressed under COX-2 inhibition. Mice lacking either EP3 or EP4 exhibited reduced wound-healing, lymphangiogenesis and recruitment of M2 macrophages, compared with wild type mice. Proliferation of cultured human lymphatic endothelial cells was not detected under PGE2 stimulation. Lymphangiogenesis and recruitment of M2 macrophages that produced VEGF-C/D were suppressed in mice treated with a COX-2 inhibitor or lacking either EP3 or EP4 during wound healing. COX-2 and EP3/EP4 signaling may be novel targets to control lymphangiogenesis in vivo. PMID:27711210

  17. [The LDL receptor family].

    Science.gov (United States)

    Meilinger, Melinda

    2002-12-29

    The members of the LDL receptor family are structurally related endocytic receptors. Our view on these receptors has considerably changed in recent years. Not only have new members of the family been identified, but also several interesting observations have been published concerning the biological function of these molecules. The LDL receptor family members are able to bind and internalize a plethora of ligands; as a consequence, they play important roles in diverse physiological processes. These receptors are key players in the lipoprotein metabolism, vitamin homeostasis, Ca2+ homeostasis, cell migration, and embryonic development. Until recently, LDL receptor family members were thought to be classic endocytic receptors that provide cells with metabolites on one hand, while regulating the concentration of their ligands in the extracellular fluids on the other hand. However, recent findings indicate that in addition to their cargo transport function, LDL receptor family members can act as signal transducers, playing important roles in the development of the central nervous system or the skeleton. Better understanding of physiological and pathophysiological functions of these molecules may open new avenues for the treatment or prevention of many disorders.

  18. Glutamate receptor agonists

    DEFF Research Database (Denmark)

    Vogensen, Stine Byskov; Greenwood, Jeremy R; Bunch, Lennart;

    2011-01-01

    The neurotransmitter (S)-glutamate [(S)-Glu] is responsible for most of the excitatory neurotransmission in the central nervous system. The effect of (S)-Glu is mediated by both ionotropic and metabotropic receptors. Glutamate receptor agonists are generally a-amino acids with one or more...... stereogenic centers due to strict requirements in the agonist binding pocket of the activated state of the receptor. By contrast, there are many examples of achiral competitive antagonists. The present review addresses how stereochemistry affects the activity of glutamate receptor ligands. The review focuses...... mainly on agonists and discusses stereochemical and conformational considerations as well as biostructural knowledge of the agonist binding pockets, which is useful in the design of glutamate receptor agonists. Examples are chosen to demonstrate how stereochemistry not only determines how the agonist...

  19. Opiate receptors: an introduction.

    Science.gov (United States)

    Carmody, J J

    1987-02-01

    Current status of opiate receptors and their agonists is reviewed--basic aspects of receptor theory, the importance of stereospecificity in drug-receptor interactions and the role of 'second messengers' in drug action. The three classes of endogenous opioids, originating from three distinct genes, are discussed: pro-opiomelanocortin, giving rise to beta-endorphin, ACTH and various MSHs; pro-enkephalin, giving methionine enkephalin and leucine enkephalin; and prodynorphin; their anatomical distribution and the main classes of receptors with which they interact, the mu-receptor, with a high affinity for met-enkephalin and beta-endorphin (as well as morphine and dynorphin A); the delta-receptor for which the primary ligand is leu-enkephalin; and the kappa-receptor which is the main target for the dynorphins. Functional roles for endogenous opioids are considered. Essentially they are inhibitory to target neurones, depressing motor reflexes, baroreflexes and nociception. They also have roles in the response to physical and psychological stress.

  20. Serotonin receptors in hippocampus.

    Science.gov (United States)

    Berumen, Laura Cristina; Rodríguez, Angelina; Miledi, Ricardo; García-Alcocer, Guadalupe

    2012-01-01

    Serotonin is an ancient molecular signal and a recognized neurotransmitter brainwide distributed with particular presence in hippocampus. Almost all serotonin receptor subtypes are expressed in hippocampus, which implicates an intricate modulating system, considering that they can be localized as autosynaptic, presynaptic, and postsynaptic receptors, even colocalized within the same cell and being target of homo- and heterodimerization. Neurons and glia, including immune cells, integrate a functional network that uses several serotonin receptors to regulate their roles in this particular part of the limbic system.

  1. Serotonin Receptors in Hippocampus

    Directory of Open Access Journals (Sweden)

    Laura Cristina Berumen

    2012-01-01

    Full Text Available Serotonin is an ancient molecular signal and a recognized neurotransmitter brainwide distributed with particular presence in hippocampus. Almost all serotonin receptor subtypes are expressed in hippocampus, which implicates an intricate modulating system, considering that they can be localized as autosynaptic, presynaptic, and postsynaptic receptors, even colocalized within the same cell and being target of homo- and heterodimerization. Neurons and glia, including immune cells, integrate a functional network that uses several serotonin receptors to regulate their roles in this particular part of the limbic system.

  2. Dopamine receptor and hypertension.

    Science.gov (United States)

    Zeng, Chunyu; Eisner, Gilbert M; Felder, Robin A; Jose, Pedro A

    2005-01-01

    Dopamine plays an important role in the pathogenesis of hypertension by regulating epithelial sodium transport and reactive oxygen and by interacting with vasopressin, renin-angiotensin, and the sympathetic nervous system. Decreased renal dopamine production and/or impaired dopamine receptor function have been reported in hypertension. Disruption of any of the dopamine receptors (D(1), D(2), D(3), D(4), and D(5)) results in hypertension. In this paper, we review the mechanisms by which hypertension develops when dopamine receptor function is perturbed.

  3. Serotonin Receptors in Hippocampus

    Science.gov (United States)

    Berumen, Laura Cristina; Rodríguez, Angelina; Miledi, Ricardo; García-Alcocer, Guadalupe

    2012-01-01

    Serotonin is an ancient molecular signal and a recognized neurotransmitter brainwide distributed with particular presence in hippocampus. Almost all serotonin receptor subtypes are expressed in hippocampus, which implicates an intricate modulating system, considering that they can be localized as autosynaptic, presynaptic, and postsynaptic receptors, even colocalized within the same cell and being target of homo- and heterodimerization. Neurons and glia, including immune cells, integrate a functional network that uses several serotonin receptors to regulate their roles in this particular part of the limbic system. PMID:22629209

  4. Alteration of introns in a hyaluronan synthase 1 (HAS1 minigene convert Pre-mRNA [corrected] splicing to the aberrant pattern in multiple myeloma (MM: MM patients harbor similar changes.

    Directory of Open Access Journals (Sweden)

    Jitra Kriangkum

    Full Text Available Aberrant pre-mRNA splice variants of hyaluronan synthase 1 (HAS1 have been identified in malignant cells from cancer patients. Bioinformatic analysis suggests that intronic sequence changes can underlie aberrant splicing. Deletions and mutations were introduced into HAS1 minigene constructs to identify regions that can influence aberrant intronic splicing, comparing the splicing pattern in transfectants with that in multiple myeloma (MM patients. Introduced genetic variations in introns 3 and 4 of HAS1 as shown here can promote aberrant splicing of the type detected in malignant cells from MM patients. HAS1Vd is a novel intronic splice variant first identified here. HAS1Vb, an intronic splice variant previously identified in patients, skips exon 4 and utilizes the same intron 4 alternative 3'splice site as HAS1Vd. For transfected constructs with unaltered introns 3 and 4, HAS1Vd transcripts are readily detectable, frequently to the exclusion of HAS1Vb. In contrast, in MM patients, HAS1Vb is more frequent than HAS1Vd. In the HAS1 minigene, combining deletion in intron 4 with mutations in intron 3 leads to a shift from HAS1Vd expression to HAS1Vb expression. The upregulation of aberrant splicing, exemplified here by the expression of HAS1Vb, is shown here to be influenced by multiple genetic changes in intronic sequences. For HAS1Vb, this includes enhanced exon 4 skipping and increased usage of alternative 3' splice sites. Thus, the combination of introduced mutations in HAS1 intron3 with introduced deletions in HAS1 intron 4 promoted a shift to an aberrant splicing pattern previously shown to be clinically significant. Most MM patients harbor genetic variations in intron 4, and as shown here, nearly half harbor recurrent mutations in HAS1 intron 3. Our work suggests that aberrant intronic HAS1 splicing in MM patients may rely on intronic HAS1 deletions and mutations that are frequent in MM patients but absent from healthy donors.

  5. Comparative analysis of hyaluronan gel and xanthan-based chlorhexidine gel, as adjunct to scaling and root planing with scaling and root planing alone in the treatment of chronic periodontitis: A preliminary study

    Directory of Open Access Journals (Sweden)

    Avinash Singh Chauhan

    2013-01-01

    Full Text Available Aim : The aim of this study was to evaluate the effects of hyaluronan (HA and chlorhexidine (CHX gels as adjunct to scaling and root planing (SRP in the treatment of chronic periodontitis. Materials and Methods: Sixty patients within the age group of 30-65 years recruited to participate in the study were randomly equally divided into three groups. Complete SRP and subgingival debridement were performed within 6 h in all the patients. For control (Group I patients, SRP was the only treatment modality given; for Group II and III patients, at least 8 teeth with 4-8 mm probing pocket depth (PPD were selected for subgingival application of HA gel and CHX gel, respectively. Clinical periodontal parameters such as gingival index, PPD, and clinical attachment level (CAL were recorded at baseline and 3 months, whereas plaque index was recorded at baseline, 1 month, and 3 months. For measuring systemic/hematological parameters, blood samples for laboratory tests for total leucocyte count (TLC, differential leucocyte count (DLC, and C-reactive protein (CRP were obtained using standard 2-mL syringe from each subject in all the three groups at baseline, 24 h, and on the 1 month and 3 months post-baseline. Results: In all the three groups, a significant reduction in PPD and gain in CAL were observed between baseline and 3 months follow-up ( P < 0.05; however, at 3 months, change in PPD and CAL was more in Group II than Group III, but the difference was non-significant, and Group I (control showed less changes in PPD and CAL than both experimental groups. Only one patient revealed positive value for CRP at baseline only, and hence could not be statistically analyzed. In all the three groups, the peak values for TLC count were observed at 24 h. At 1-month and 3-month intervals, a significant improvement in TLC and DLC counts was observed among the experimental (HA gel/SRP and Xan-CHX gel groups as compared to control group (SRP alone.

  6. Recognition receptors in biosensors

    CERN Document Server

    Zourob, Mohammed

    2010-01-01

    This book presents a significant and up-to-date review of the various recognition receptors, their immobilization, and an overview of the used surface characterization techniques. It includes more than 150 illustrations that help explain the ideas presented.

  7. Somatostatin receptor skintigrafi

    DEFF Research Database (Denmark)

    Rasmussen, Karin; Nielsen, Jørn Theil; Rehling, Michael

    2005-01-01

    Somatostatin receptor scintigraphy (SRS) is a very valuable imaging technique for visualisation of a diversity of neuroendocrine tumours. The sensitivity for localisation of carcinoid tumours is high, but somewhat lower for other neuroendocrine tumours. The methodology, multiple clinical aspects...

  8. Update on Melatonin Receptors. IUPHAR Review. : Melatonin Receptors

    OpenAIRE

    Jockers, Ralf; Delagrange, Philippe; Dubocovich, Margarita ,; Markus, Regina ,; Renault, Nicolas; Tosini, Gianluca; Cecon, Erika; Zlotos, Darius Paul

    2016-01-01

    International audience; Melatonin receptors are seven transmembrane-spanning proteins belonging to the G protein-coupled receptor super-family. In mammals, two melatonin receptor subtypes exit MT1 and MT2 encoded by the MTNR1A and MTNR1B genes, respectively. The current review provides an update on melatonin receptors by the corresponding sub-committee of the International Union of Basic and Clinical Pharmacology. We will highlight recent developments of melatonin receptor ligands, including ...

  9. Serotonin Receptors in Hippocampus

    OpenAIRE

    Laura Cristina Berumen; Angelina Rodríguez; Ricardo Miledi; Guadalupe García-Alcocer

    2012-01-01

    Serotonin is an ancient molecular signal and a recognized neurotransmitter brainwide distributed with particular presence in hippocampus. Almost all serotonin receptor subtypes are expressed in hippocampus, which implicates an intricate modulating system, considering that they can be localized as autosynaptic, presynaptic, and postsynaptic receptors, even colocalized within the same cell and being target of homo- and heterodimerization. Neurons and glia, including immune cells, integrate a fu...

  10. Receptors for enterovirus 71

    OpenAIRE

    Yamayoshi, Seiya; Fujii, Ken; Koike, Satoshi

    2014-01-01

    Enterovirus 71 (EV71) is one of the major causative agents of hand, foot and mouth disease (HFMD). Occasionally, EV71 infection is associated with severe neurological diseases, such as acute encephalitis, acute flaccid paralysis and cardiopulmonary failure. Several molecules act as cell surface receptors that stimulate EV71 infection, including scavenger receptor B2 (SCARB2), P-selectin glycoprotein ligand-1 (PSGL-1), sialylated glycan, heparan sulfate and annexin II (Anx2). SCARB2 plays crit...

  11. Adenosine receptor neurobiology: overview.

    Science.gov (United States)

    Chen, Jiang-Fan; Lee, Chien-fei; Chern, Yijuang

    2014-01-01

    Adenosine is a naturally occurring nucleoside that is distributed ubiquitously throughout the body as a metabolic intermediary. In the brain, adenosine functions as an important upstream neuromodulator of a broad spectrum of neurotransmitters, receptors, and signaling pathways. By acting through four G-protein-coupled receptors, adenosine contributes critically to homeostasis and neuromodulatory control of a variety of normal and abnormal brain functions, ranging from synaptic plasticity, to cognition, to sleep, to motor activity to neuroinflammation, and cell death. This review begun with an overview of the gene and genome structure and the expression pattern of adenosine receptors (ARs). We feature several new developments over the past decade in our understanding of AR functions in the brain, with special focus on the identification and characterization of canonical and noncanonical signaling pathways of ARs. We provide an update on functional insights from complementary genetic-knockout and pharmacological studies on the AR control of various brain functions. We also highlight several novel and recent developments of AR neurobiology, including (i) recent breakthrough in high resolution of three-dimension structure of adenosine A2A receptors (A2ARs) in several functional status, (ii) receptor-receptor heterodimerization, (iii) AR function in glial cells, and (iv) the druggability of AR. We concluded the review with the contention that these new developments extend and strengthen the support for A1 and A2ARs in brain as therapeutic targets for neurologic and psychiatric diseases.

  12. Imidazoline receptors ligands

    Directory of Open Access Journals (Sweden)

    Agbaba Danica

    2012-01-01

    Full Text Available Extensive biochemical and pharmacological studies have determined three different subtypes of imidazoline receptors: I1-imidazoline receptors (I1-IR involved in central inhibition of sympathicus that produce hypotensive effect; I2-imidazoline receptors (I2-IR modulate monoamine oxidase B activity (MAO-B; I3-imidazoline receptors (I3-IR regulate insulin secretion from pancreatic β-cells. Therefore, the I1/I2/I3 imidazoline receptors are selected as new, interesting targets for drug design and discovery. Novel selective I1/I2/I3 agonists and antagonists have been recently developed. In the present review, we provide a brief update to the field of imidazoline research, highlighting some of the chemical diversity and progress made in the 2D-QSAR, 3D-QSAR and quantitative pharmacophore development studies of I1-IR and I2-IR imidazoline receptor ligands. Theoretical studies of I3-IR ligands are not yet performed because of insufficient number of synthesized I3-IR ligands.

  13. Ionotropic crustacean olfactory receptors.

    Directory of Open Access Journals (Sweden)

    Elizabeth A Corey

    Full Text Available The nature of the olfactory receptor in crustaceans, a major group of arthropods, has remained elusive. We report that spiny lobsters, Panulirus argus, express ionotropic receptors (IRs, the insect chemosensory variants of ionotropic glutamate receptors. Unlike insects IRs, which are expressed in a specific subset of olfactory cells, two lobster IR subunits are expressed in most, if not all, lobster olfactory receptor neurons (ORNs, as confirmed by antibody labeling and in situ hybridization. Ligand-specific ORN responses visualized by calcium imaging are consistent with a restricted expression pattern found for other potential subunits, suggesting that cell-specific expression of uncommon IR subunits determines the ligand sensitivity of individual cells. IRs are the only type of olfactory receptor that we have detected in spiny lobster olfactory tissue, suggesting that they likely mediate olfactory signaling. Given long-standing evidence for G protein-mediated signaling in activation of lobster ORNs, this finding raises the interesting specter that IRs act in concert with second messenger-mediated signaling.

  14. Presynaptic P2 receptors?

    Science.gov (United States)

    Stone, T W; O'Kane, E M; Nikbakht, M R; Ross, F M

    2000-07-01

    Although the emphasis in ATP research has been on postjunctional receptors, there is also evidence for presynaptic receptors regulating transmitter release in the autonomic nervous system. Recent work has attempted to identify similar mechanisms in the central nervous system. Some of the existing results can be explained by the metabolism of nucleotides to adenosine or adenosine 5'-monophosphate (AMP). However, studies of presynaptic effects using sensitive electrophysiological tests such as paired-pulse interactions indicate that nucleotides can act at presynaptic sites, but that their effects may be mediated by a release of adenosine. Results are also described which indicate that, under some conditions, nucleotides can mediate phenomena such as long-term potentiation, which probably involves a significant presynaptic element. In part these effects may involve a nucleotide-induced release of adenosine and the simultaneous activation of P1 and P2 receptors.

  15. Human presynaptic receptors.

    Science.gov (United States)

    Schlicker, Eberhard; Feuerstein, Thomas

    2017-04-01

    Presynaptic receptors are sites at which transmitters, locally formed mediators or hormones inhibit or facilitate the release of a given transmitter from its axon terminals. The interest in the identification of presynaptic receptors has faded in recent years and it may therefore be justified to give an overview of their occurrence in the autonomic and central nervous system; this review will focus on presynaptic receptors in human tissues. Autoreceptors are presynaptic receptors at which a given transmitter restrains its further release, though in some instances may also increase its release. Inhibitory autoreceptors represent a typical example of a negative feedback; they are tonically activated by the respective endogenous transmitter and/or are constitutively active. Autoreceptors also play a role under pathophysiological conditions, e.g. by limiting the massive noradrenaline release occurring during congestive heart failure. They can be used for therapeutic purposes; e.g., the α2-adrenoceptor antagonist mirtazapine is used as an antidepressant and the inverse histamine H3 receptor agonist pitolisant has been marketed as a new drug for the treatment of narcolepsy in 2016. Heteroreceptors are presynaptic receptors at which transmitters from adjacent neurons, locally formed mediators (e.g. endocannabinoids) or hormones (e.g. adrenaline) can inhibit or facilitate transmitter release; they may be subject to an endogenous tone. The constipating effect of the sympathetic nervous system or of the antihypertensive drug clonidine is related to the activation of inhibitory α2-adrenoceptors on postganglionic parasympathetic neurons. Part of the stimulating effect of adrenaline on the sympathetic nervous system during stress is related to its facilitatory effect on noradrenaline release via β2-adrenoceptors.

  16. Biomimetic Receptors and Sensors

    Directory of Open Access Journals (Sweden)

    Franz L. Dickert

    2014-11-01

    Full Text Available In biomimetics, living systems are imitated to develop receptors for ions, molecules and bioparticles. The most pertinent idea is self-organization in analogy to evolution in nature, which created the key-lock principle. Today, modern science has been developing host-guest chemistry, a strategy of supramolecular chemistry for designing interactions of analytes with synthetic receptors. This can be realized, e.g., by self-assembled monolayers (SAMs or molecular imprinting. The strategies are used for solid phase extraction (SPE, but preferably in developing recognition layers of chemical sensors.

  17. Beyond the Receptor

    Institute of Scientific and Technical Information of China (English)

    Russell Jones

    2008-01-01

    @@ Had this Special Issue on plant hormones been published 5 years ago,it is likely that details about biosynthetic pathways would have taken center stage.As articles in this issue show,however,the field of plant hormone research has progressed rapidly and is now moving beyond the search for receptors.Progress in research on the mechanism of action of plant hormones has been rapid;receptors for the main classes of hormones have been identified;and the search is on for players downstream in signal-transduction chains.

  18. Assays for calcitonin receptors

    Energy Technology Data Exchange (ETDEWEB)

    Teitelbaum, A.P.; Nissenson, R.A.; Arnaud, C.D.

    1985-01-01

    The assays for calcitonin receptors described focus on their use in the study of the well-established target organs for calcitonin, bone and kidney. The radioligand used in virtually all calcitonin binding studies is /sup 125/I-labelled salmon calcitonin. The lack of methionine residues in this peptide permits the use of chloramine-T for the iodination reaction. Binding assays are described for intact bone, skeletal plasma membranes, renal plasma membranes, and primary kidney cell cultures of rats. Studies on calcitonin metabolism in laboratory animals and regulation of calcitonin receptors are reviewed.

  19. Chemokine Receptors and Transplantation

    Institute of Scientific and Technical Information of China (English)

    Jinquan Tan; Gang Zhou

    2005-01-01

    A complex process including both the innate and acquired immune responses results in allograft rejection. Some chemokine receptors and their ligands play essential roles not only for leukocyte migration into the graft but also in facilitating dendritic and T cell trafficking between lymph nodes and the transplant in the early and late stage of the allogeneic response. This review focuses on the impact of these chemoattractant proteins on transplant outcome and novel diagnostic and therapeutic approaches for antirejection therapy based on targeting of chemokine receptors and/or their ligands. Cellular & Molecular Immunology.

  20. Modulation of bleomycin-induced lung fibrosis by pegylated hyaluronidase and dopamine receptor antagonist in mice.

    Directory of Open Access Journals (Sweden)

    Evgenii Germanovich Skurikhin

    Full Text Available Hyaluronidases are groups of enzymes that degrade hyaluronic acid (HA. To stop enzymatic hydrolysis we modified testicular hyaluronidase (HYAL by activated polyethylene oxide with the help of electron-beam synthesis. As a result we received pegylated hyaluronidase (pegHYAL. Spiperone is a selective D2 dopamine receptor antagonist. It was demonstrated on the model of a single bleomycin damage of alveolar epithelium that during the inflammatory phase monotherapy by pegHYAL or spiperone reduced the populations of hematopoietic stem /progenitor cells in the lung parenchyma. PegHYAL also reduced the levels of transforming growth factor (TGF-β, interleukin (IL-1β, tumor necrosis factor (TNF-α in the serum and lungs, while spiperone reduced the level of the serum IL-1β. Polytherapy by spiperone and pegHYAL caused the increase of the quantity of hematopoietic stem/ progenitor cells in the lungs. Such an influx of blood cell precursors was observed on the background of considerable fall level of TGF-β and the increase level of TNF-α in the serum and lungs. These results show pegHYAL reduced the bleomycin-induced fibrosis reaction (production and accumulation of collagen in the lung parenchyma. This effect was observed at a single and repetitive bleomycin damage of alveolar epithelium, the antifibrotic activity of pegHYAL surpassing the activity of testicular HYAL. The antifibrotic effect of pegHYAL is enhanced by an additional instillation of spiperone. Therapy by pegHYAL causes the flow of CD31‒ CD34‒ CD45‒ CD44+ CD73+ CD90+ CD106+-cells into the fibrous lungs. These cells are incapable of differentiating into fibroblast cells. Spiperone instillation separately or together with pegHYAL reduced the MSC-like cells considerably. These data enable us to assume, that pegHYAL is a new and promising instrument both for preventive and therapy of toxic pneumofibrosis. The blockage of D2 dopamine receptors with the following change of hyaluronan

  1. UniProt search blastx result: AK288414 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK288414 J090031D01 O75330|HMMR_HUMAN Hyaluronan mediated motility receptor (Intrac...ellular hyaluronic acid-binding protein) (Receptor for hyaluronan-mediated motility) (CD168 antigen) - Homo sapiens (Human) 9.00E-11 ...

  2. SwissProt search result: AK110401 [KOME

    Lifescience Database Archive (English)

    Full Text Available AK110401 002-165-F10 (Q8CFM6) Stabilin-2 precursor (Hyaluronan receptor for endocytosis...) [Contains: 175 kDa stabilin-2 (175 kDa hyaluronan receptor for endocytosis)] (Fragment) STAB2_RAT 5e-13 ...

  3. Angiotensin type 2 receptor (AT2R) and receptor Mas

    DEFF Research Database (Denmark)

    Villela, Daniel; Leonhardt, Julia; Patel, Neal

    2015-01-01

    The angiotensin type 2 receptor (AT2R) and the receptor Mas are components of the protective arms of the renin-angiotensin system (RAS), i.e. they both mediate tissue protective and regenerative actions. The spectrum of actions of these two receptors and their signalling mechanisms display striking...

  4. Characterization of melanocortin receptors.

    Science.gov (United States)

    Goetz, Aaron S; Ignar, Diane M

    2003-11-01

    This unit describes a Scintillation Proximity Assay (SPA) for the measurement of ligand binding to melanocortin receptors (MCRs) using membranes prepared from cell lines stably expressing recombinant MCRs. It provides a facile method for determining the affinity of compounds at MC1R, MC3R, MC4R, or MC5R.

  5. P2-purinerge receptorer

    DEFF Research Database (Denmark)

    Solgaard, Marie; Jørgensen, Niklas Rye

    2005-01-01

    and by osteoclasts, and agonist binding affects cell proliferation, differentiation, activity and apoptosis. With increasing knowledge of the function and role of these receptors in bone biology, they will undoubtedly be a future target for the design of new drugs which can be used for treatment of metabolic bone...

  6. Meeting report: nuclear receptors

    DEFF Research Database (Denmark)

    Tuckermann, Jan; Bourguet, William; Mandrup, Susanne

    2010-01-01

    The biannual European Molecular Biology Organization (EMBO) conference on nuclear receptors was organized by Beatrice Desvergne and Laszlo Nagy and took place in Cavtat near Dubrovnik on the Adriatic coast of Croatia September 25-29, 2009. The meeting brought together researchers from all over...

  7. Glutamate receptor ligands

    DEFF Research Database (Denmark)

    Guldbrandt, Mette; Johansen, Tommy N; Frydenvang, Karla Andrea;

    2002-01-01

    Homologation and substitution on the carbon backbone of (S)-glutamic acid [(S)-Glu, 1], as well as absolute stereochemistry, are structural parameters of key importance for the pharmacological profile of (S)-Glu receptor ligands. We describe a series of methyl-substituted 2-aminoadipic acid (AA......-ray crystallographic analyses, chemical correlation, and CD spectral analyses. The effects of the individual stereoisomers at ionotropic and metabotropic (S)-Glu receptors (iGluRs and mGluRs) were characterized. Compounds with S-configuration at the alpha-carbon generally showed mGluR2 agonist activity of similar...... limited effect on pharmacology. Structure-activity relationships at iGluRs in the rat cortical wedge preparation showed a complex pattern, some compounds being NMDA receptor agonists [e.g., EC(50) =110 microM for (2S,5RS)-5-methyl-AA (6a,b)] and some compounds showing NMDA receptor antagonist effects [e...

  8. Ginkgolides and glycine receptors

    DEFF Research Database (Denmark)

    Jaracz, Stanislav; Nakanishi, Koji; Jensen, Anders A.

    2004-01-01

    Ginkgolides from the Ginkgo biloba tree are diterpenes with a cage structure consisting of six five-membered rings and a unique tBu group. They exert a variety of biological properties. In addition to being antagonists of the platelet activating factor receptor (PAFR), it has recently been shown...

  9. Androgen receptor mutations

    NARCIS (Netherlands)

    A.O. Brinkmann (Albert); G.W. Jenster (Guido); C. Ris-Stalpers (Carolyn); J.A.G.M. van der Korput (J. A G M); H.T. Brüggenwirth (Hennie); A.L.M. Boehmer (Annemie); J. Trapman (Jan)

    1995-01-01

    textabstractMale sexual differentiation and development proceed under direct control of androgens. Androgen action is mediated by the intracellular androgen receptor, which belongs to the superfamily of ligand-dependent transcription factors. At least three pathological situations are associated wit

  10. Metformin and insulin receptors

    Energy Technology Data Exchange (ETDEWEB)

    Vigneri, R.; Gullo, D.; Pezzino, V.

    The authors evaluated the effect of metformin (N,N-dimethylbiguanide), a biguanide known to be less toxic than phenformin, on insulin binding to its receptors, both in vitro and in vivo. Specific /sup 125/I-insulin binding to cultured IM-9 human lymphocytes and MCF-7 human breast cancer cells was determined after preincubation with metformin. Specific /sup 125/I-insulin binding to circulating monocytes was also evaluated in six controls, eight obese subjects, and six obese type II diabetic patients before and after a short-term treatment with metformin. Plasma insulin levels and blood glucose were also measured on both occasions. Metformin significantly increased insulin binding in vitro to both IM-9 lymphocytes and MCF-7 cells; the maximum increment was 47.1% and 38.0%, respectively. Metformin treatment significantly increased insulin binding in vivo to monocytes of obese subjects and diabetic patients. Scatchard analysis indicated that the increased binding was mainly due to an increase in receptor capacity. Insulin binding to monocytes of normal controls was unchanged after metformin as were insulin levels in all groups; blood glucose was significantly reduced after metformin only in diabetic patients. These data indicate that metformin increases insulin binding to its receptors in vitro and in vivo. The effect in vivo is observed in obese subjects and in obese type II diabetic patients, paralleling the clinical effectiveness of this antidiabetic agent, and is not due to receptor regulation by circulating insulin, since no variation in insulin levels was recorded.

  11. Levamisole receptors: a second awakening

    Science.gov (United States)

    Martin, Richard J.; Robertson, Alan P.; Buxton, Samuel K.; Beech, Robin N.; Charvet, Claude L.; Neveu, Cedric

    2012-01-01

    Levamisole and pyrantel are old (1965) but useful anthelmintics that selectively activate nematode acetylcholine ion-channel receptors; they are used to treat roundworm infections in humans and animals. Interest in their actions has surged, giving rise to new knowledge and technical advances, including an ability to reconstitute receptors that reveal more details of modes of action/resistance. We now know that the receptors are plastic and may form diverse species-dependent subtypes of receptor with different sensitivities to individual cholinergic anthelmintics. Understanding the biology of the levamisole receptors is expected to inform other studies on anthelmintics (ivermectin and emodepside) that act on ion-channels. PMID:22607692

  12. Histamine H3-receptor isoforms.

    Science.gov (United States)

    Bakker, R A

    2004-10-01

    Increasing evidence supports a role for HA as a neurotransmitter and neuromodulator in various brain functions, including emotion, cognition, and feeding. The recent cloning of the histamine H3 receptor allowed for the subsequent cloning of a variety of H3 receptor isoforms from different species as well as the H4 receptor. As a result a wide variety of H3-receptor isoforms are now known that display differential brain expression patterns and signalling properties. These recent discoveries are discussed in view of the growing interest of the H3 receptor as a target for the development of potential therapeutics.

  13. Virally encoded 7TM receptors

    DEFF Research Database (Denmark)

    Rosenkilde, M M; Waldhoer, M; Lüttichau, H R

    2001-01-01

    A number of herpes- and poxviruses encode 7TM G-protein coupled receptors most of which clearly are derived from their host chemokine system as well as induce high expression of certain 7TM receptors in the infected cells. The receptors appear to be exploited by the virus for either immune evasion...... in various parts of the viral life cyclus. Most of the receptors encoded by human pathogenic virus are still orphan receptors, i.e. the endogenous ligand is unknown. In the few cases where it has been possible to characterize these receptors pharmacologically, they have been found to bind a broad spectrum...... expression of this single gene in certain lymphocyte cell lineages leads to the development of lesions which are remarkably similar to Kaposi's sarcoma, a human herpesvirus 8 associated disease. Thus, this and other virally encoded 7TM receptors appear to be attractive future drug targets....

  14. Receptor tyrosine kinases in carcinogenesis.

    Science.gov (United States)

    Zhang, Xiao-Ying; Zhang, Pei-Ying

    2016-11-01

    Receptor tyrosine kinases (RTKs) are cell surface glycoproteins with enzymatic activity involved in the regulation of various important functions. In all-important physiological functions including differentiation, cell-cell interactions, survival, proliferation, metabolism, migration and signaling these receptors are the key players of regulation. Additionally, mutations of RTKs or their overexpression have been described in many human cancers and are being explored as a novel avenue for a new therapeutic approach. Some of the deregulated RTKs observed to be significantly affected in cancers included vascular endothelial growth factor receptor, epidermal growth factor receptor, fibroblast growth factor receptor, RTK-like orphan receptor 1 (ROR1) and the platelet-derived growth factor receptor. These deregulated RTKs offer attractive possibilities for the new anticancer therapeutic approach involving specific targeting by monoclonal antibodies as well as kinase. The present review aimed to highlight recent perspectives of RTK ROR1 in cancer.

  15. TSH RECEPTOR AUTOANTIBODIES

    Science.gov (United States)

    Michalek, Krzysztof; Morshed, Syed A.; Latif, Rauf; Davies, Terry F.

    2009-01-01

    Thyrotropin receptor autoantibodies (TSHR-Abs) of the stimulating variety are the hallmark of Graves’ disease. The presence of immune defects leading to synthesis of TSHR-Abs causes hyperthyroidism and is associated with other extrathyroidal manifestations. Further characterization of these antibodies has now been made possible by the generation of monoclonal antibodies with this unique stimulating capacity as well as similar TSHR-Abs not associated with hyperthyroidism. Their present classification divides TSHR-Abs into stimulating, blocking (competing with TSH binding) and neutral (no signaling). Recent studies using monoclonal TSHR-Abs has revealed that stimulating and blocking antibodies bind to the receptor using mostly conformational epitopes, whilst neutral antibodies utilize exclusively linear peptides. Subtle differences in epitopes for stimulating and blocking antibodies account for the diversity of their biological actions. Recently non-classical signaling elicited by neutral antibodies has also been described, raising the need for a new classification of TSHR-Abs. PMID:19332151

  16. Ligand-Receptor Interactions

    CERN Document Server

    Bongrand, Pierre

    2008-01-01

    The formation and dissociation of specific noncovalent interactions between a variety of macromolecules play a crucial role in the function of biological systems. During the last few years, three main lines of research led to a dramatic improvement of our understanding of these important phenomena. First, combination of genetic engineering and X ray cristallography made available a simultaneous knowledg of the precise structure and affinity of series or related ligand-receptor systems differing by a few well-defined atoms. Second, improvement of computer power and simulation techniques allowed extended exploration of the interaction of realistic macromolecules. Third, simultaneous development of a variety of techniques based on atomic force microscopy, hydrodynamic flow, biomembrane probes, optical tweezers, magnetic fields or flexible transducers yielded direct experimental information of the behavior of single ligand receptor bonds. At the same time, investigation of well defined cellular models raised the ...

  17. The interleukin-4 receptor: signal transduction by a hematopoietin receptor.

    Science.gov (United States)

    Keegan, A D; Pierce, J H

    1994-02-01

    Over the last several years, the receptors for numerous cytokines have been molecularly characterized. Analysis of their amino acid sequences shows that some of these receptors bear certain motifs in their extracellular domains that define a family of receptors called the Hematopoietin receptor superfamily. Significant advances in characterizing the structure, function, and mechanisms of signal transduction have been made for several members of this family. The purpose of this review is to discuss the recent advances made for one of the family members, the interleukin (IL) 4 receptor. Other receptor systems have recently been reviewed elsewhere. The IL-4 receptor consists of, at the minimum, the cloned 140 kDa IL-4-binding chain with the potential for associating with other chains. The IL-4 receptor transduces its signal by activating a tyrosine kinase that phosphorylates cellular substrates, including the receptor itself, and the 170 kDa substrate called 4PS. Phosphorylated 4PS interacts with the SH2 domain of the enzyme PI-3'-kinase and increases its enzymatic activity. These early events in the IL-4 receptor initiated signaling pathway may trigger a series of signals that will ultimately lead to an IL-4 specific biologic outcome.

  18. [Lipoprotein receptors. Old acquaintances and newcomers].

    Science.gov (United States)

    Ducobu, J

    1997-02-01

    Lipoprotein receptors are plasma membrane proteins of high affinity which interact with circulating lipoprotein particles. The well characterized LDL receptor continues to be analysed and some new findings on its intracellular mechanisms of action have emerged. New lipoprotein receptors have recently been described: the chylomicron remnant receptor or LDL-related protein (LRP), the lipolysis stimulated receptor (LSR), the very low density lipoprotein receptor (VLDLR), the HDL receptor (HDLR) and the scavenger receptor (SR). The molecular details of the receptors will facilitate the development of new therapeutic means to improve receptor-mediated clearance of lipoproteins.

  19. Similarity of Bovine Rotavirus Receptor and Human Rotavirus Receptor

    Institute of Scientific and Technical Information of China (English)

    苏琦华; 訾自强; 潘菊芬; 徐燕

    2004-01-01

    The monoclonal antibody against bovine rotavirus (BRV) receptor (BRV-R-mAb) was used to explore the similarity between the receptors of BRV and human rotavirus (HRV). ELISA, dot immunobinding assay, cell protection assay, solid-phase assay and immunohistochemistry method were applied. BRV-R-mAb bound both anti-BRV IgG and anti-HRV IgG respectively and could protect MA 104 cells against BRV and HRV challenges. Immunohistochemistry test showed that there were rotavirus receptors on the surfaces of foetal intestinal, tracheal mucosa and MA 104 cells membrane. We purified the rotavirus receptors on MA 104 ceils, which could bind both BRV and HRV in vitro. It is concluded that BRV receptor and HRV receptor are homogenous proteins and can be recognized by both BRV and HRV.

  20. Melatonin Receptor Genes in Vertebrates

    Directory of Open Access Journals (Sweden)

    Hua Dong Yin

    2013-05-01

    Full Text Available Melatonin receptors are members of the G protein-coupled receptor (GPCR family. Three genes for melatonin receptors have been cloned. The MT1 (or Mel1a or MTNR1A and MT2 (or Mel1b or MTNR1B receptor subtypes are present in humans and other mammals, while an additional melatonin receptor subtype, Mel1c (or MTNR1C, has been identified in fish, amphibians and birds. Another melatonin related orphan receptor, GPR50, which does not bind melatonin, is found exclusively in mammals. The hormone melatonin is secreted primarily by the pineal gland, with highest levels occurring during the dark period of a circadian cycle. This hormone acts systemically in numerous organs. In the brain, it is involved in the regulation of various neural and endocrine processes, and it readjusts the circadian pacemaker, the suprachiasmatic nucleus. This article reviews recent studies of gene organization, expression, evolution and mutations of melatonin receptor genes of vertebrates. Gene polymorphisms reveal that numerous mutations are associated with diseases and disorders. The phylogenetic analysis of receptor genes indicates that GPR50 is an outgroup to all other melatonin receptor sequences. GPR50 may have separated from a melatonin receptor ancestor before the split between MTNR1C and the MTNR1A/B ancestor.

  1. Vascular endothelial growth factor C induces differentiation of bone marrow mesenchymal stem cells into lymphatic endothelial cells%血管内皮生长因子C诱导骨髓间充质干细胞分化为淋巴管内皮细胞的研究

    Institute of Scientific and Technical Information of China (English)

    李波; 刘艳丽; 魏璐婉; 王静; 刘执玉; 丁兆习

    2011-01-01

    Objective To study the differentiation potentiality and inducement conditions of bone marrow mesenchymal stem cells (BMSCs) into lymphatic endothelial cells (LECs), and to provide an ideal source of LECs for lymphatic regeneration and reconstruction. Methods BMSCs were isolated from the bone marrow of SD rats, and the surface antigens CD31, CD14, CD29 and CD90 on BMSCs were detected by flow cytometry. Purified BMSCs were cultured for 10 days in the conditioned medium with vascular endothelial growth factor C (VEGF-C) (50ng/mL). Then, expressions of lymphatic endothelial cell markers, (prospero ho-meobox protein 1 (Prox-1) and lymphatic vessel endothelial receptor 1 (LYVE-1), were detected by Western blot and immunofluorescence. Results BMSCs were typically fusiform in shape and circulate in arrangement, while they transformed into polygonal cells after co-culture with VEGF-C. Flow cytometry showed that expressions of surface antigens CD29 and CD90 on BMSCs were positive, however, CD31and CD14 were negative. After induction with VEGF-C, Western blot and immunofluorescence showed that prox-1 and LYVE-1 were expressed in differentiated BMSCs, while they were not expressed in undifferentiated BMSCs in the control group. Conclusion BMSCs can be induced to express the lymphatic specific antigen and to differentiate into LECs by VEGF-C in vitro.%目的 研究骨髓间充质干细胞向淋巴管内皮细胞分化的潜能及条件,为淋巴管再生和重建提供理想的细胞来源.方法 分离SD大鼠骨髓间充质干细胞,流式细胞仪检测骨髓间充质干细胞表面抗原CD31、CD14、CD29和CD90.将纯化的骨髓间充质干细胞加血管内皮生长因子C(VEGF-C)50 ng/mL诱导培养10 d,Western-blot法与免疫荧光染色法检测细胞中淋巴管内皮细胞标记物Prox-1和LYVE-1的表达.结果 骨髓间充质干细胞呈现典型的梭形和旋涡状排列;经VEGF-C诱导后,细胞变短、呈多边形.流式细胞学显示,分离培养的骨

  2. Flavivirus Entry Receptors: An Update

    Directory of Open Access Journals (Sweden)

    Manuel Perera-Lecoin

    2013-12-01

    Full Text Available Flaviviruses enter host cells by endocytosis initiated when the virus particles interact with cell surface receptors. The current model suggests that flaviviruses use at least two different sets of molecules for infectious entry: attachment factors that concentrate and/or recruit viruses on the cell surface and primary receptor(s that bind to virions and direct them to the endocytic pathway. Here, we present the currently available knowledge regarding the flavivirus receptors described so far with specific attention to C-type lectin receptors and the phosphatidylserine receptors, T-cell immunoglobulin and mucin domain (TIM and TYRO3, AXL and MER (TAM. Their role in flavivirus attachment and entry as well as their implication in the virus biology will be discussed in depth.

  3. Angiotensin II receptors in testes

    Energy Technology Data Exchange (ETDEWEB)

    Millan, M.A.; Aguilera, G.

    1988-05-01

    Receptors for angiotensin II (AII) were identified and characterized in testes of rats and several primate species. Autoradiographic analysis of the binding of 125I-labeled (Sar1,Ile8)AII to rat, rhesus monkey, cebus monkey, and human testicular slide-mounted frozen sections indicated specific binding to Leydig cells in the interstitium. In rat collagenase-dispersed interstitial cells fractionated by Percoll gradient, AII receptor content was parallel to that of hCG receptors, confirming that the AII receptors are in the Leydig cells. In rat dispersed Leydig cells, binding was specific for AII and its analogs and of high affinity (Kd, 4.8 nM), with a receptor concentration of 15 fmol/10(6) cells. Studies of AII receptors in rat testes during development reveals the presence of high receptor density in newborn rats which decreases toward the adult age (4934 +/- 309, 1460 +/- 228, 772 +/- 169, and 82 +/- 12 fmol/mg protein at 5, 15, 20, and 30 days of age, respectively) with no change in affinity. At all ages receptors were located in the interstitium, and the decrease in binding was parallel to the decrease in the interstitial to tubular ratio observed with age. AII receptor properties in membrane-rich fractions from prepuberal testes were similar in the rat and rhesus monkey. Binding was time and temperature dependent, reaching a plateau at 60 min at 37 C, and was increased by divalent cations, EGTA, and dithiothreitol up to 0.5 mM. In membranes from prepuberal monkey testes, AII receptors were specific for AII analogs and of high affinity (Kd, 4.2 nM) with a receptor concentration of 7599 +/- 1342 fmol/mg protein. The presence of AII receptors in Leydig cells in rat and primate testes in conjunction with reports of the presence of other components of the renin-angiotensin system in the testes suggests that the peptide has a physiological role in testicular function.

  4. Uncompetitive antagonism of AMPA receptors

    DEFF Research Database (Denmark)

    Andersen, Trine F; Tikhonov, Denis B; Bølcho, Ulrik;

    2006-01-01

    Philanthotoxins are uncompetitive antagonists of Ca2+-permeable AMPA receptors presumed to bind to the pore-forming region, but a detailed molecular mechanism for this interaction is missing. Here a small library of novel philanthotoxins was designed and synthesized using a solid-phase strategy. ...... polyamine toxins antagonize the AMPA receptor ion channel and provide the basis for rational development of uncompetitive antagonists of AMPA receptors....

  5. GABAρ1/GABAAα1 receptor chimeras to study receptor desensitization

    Science.gov (United States)

    Martínez-Torres, Ataúlfo; Demuro, Angelo; Miledi, Ricardo

    2000-01-01

    γ-Aminobutyrate type C (GABAC) receptors are ligand-gated ion channels that are expressed preponderantly in the vertebrate retina and are characterized, among other things, by a very low rate of desensitization and resistance to the specific GABAA antagonist bicuculline. To examine which structural elements determine the nondesensitizing character of the human homomeric ρ1 receptor, we used a combination of gene chimeras and electrophysiology of receptors expressed in Xenopus oocytes. Two chimeric genes were constructed, made up of portions of the ρ1-subunit and of the α1-subunit of the GABAA receptor. When expressed in Xenopus oocytes, one chimeric gene (ρ1/α1) formed functional homooligomeric receptors that were fully resistant to bicuculline and were blocked by the specific GABAC antagonist (1,2,5,6-tetrahydropyridine-4-yl)methylphosphinic acid and by zinc. Moreover, these chimeric receptors had a fast-desensitizing component, even faster than that of heterooligomeric GABAA receptors, in striking contrast to the almost nil desensitization of wild-type ρ1 (wt ρ1) receptors. To see whether the fast-desensitizing characteristic of the chimera was determined by the amino acids forming the ion channels, we replaced the second transmembrane segment (TM2) of ρ1 by that of the α1-subunit of GABAA. Although the α1-subunit forms fast-desensitizing receptors when coexpressed with other GABAA subunits, the sole transfer of the α1TM2 segment to ρ1 was not sufficient to form desensitizing receptors. All this suggests that the slow-desensitizing trait of ρ1 receptors is determined by a combination of several interacting domains along the molecule. PMID:10725369

  6. Renal dopamine receptors and hypertension.

    Science.gov (United States)

    Hussain, Tahir; Lokhandwala, Mustafa F

    2003-02-01

    Dopamine has been recognized as an important modulator of central as well as peripheral physiologic functions in both humans and animals. Dopamine receptors have been identified in a number of organs and tissues, which include several regions within the central nervous system, sympathetic ganglia and postganglionic nerve terminals, various vascular beds, the heart, the gastrointestinal tract, and the kidney. The peripheral dopamine receptors influence cardiovascular and renal function by decreasing afterload and vascular resistance and promoting sodium excretion. Within the kidney, dopamine receptors are present along the nephron, with highest density on proximal tubule epithelial cells. It has been reported that there is a defective dopamine receptor, especially D(1) receptor function, in the proximal tubule of various animal models of hypertension as well as in humans with essential hypertension. Recent reports have revealed the site of and the molecular mechanisms responsible for the defect in D(1) receptors in hypertension. Moreover, recent studies have also demonstrated that the disruption of various dopamine receptor subtypes and their function produces hypertension in rodents. In this review, we present evidence that dopamine and dopamine receptors play an important role in regulating renal sodium excretion and that defective renal dopamine production and/or dopamine receptor function may contribute to the development of various forms of hypertension.

  7. Leptin and its receptors.

    Science.gov (United States)

    Wada, Nobuhiro; Hirako, Satoshi; Takenoya, Fumiko; Kageyama, Haruaki; Okabe, Mai; Shioda, Seiji

    2014-11-01

    Leptin is mainly produced in the white adipose tissue before being secreted into the blood and transported across the blood-brain barrier. Leptin binds to a specific receptor (LepR) that has numerous subtypes (LepRa, LepRb, LepRc, LepRd, LepRe, and LepRf). LepRb, in particular, is expressed in several brain nuclei, including the arcuate nucleus, the paraventricular nucleus, and the dorsomedial, lateral and ventromedial regions of the hypothalamus. LepRb is also co-expressed with several neuropeptides, including proopiomelanocortin, neuropeptide Y, galanin, galanin-like peptide, gonadotropin-releasing hormone, tyrosine hydroxylase and neuropeptide W. Functionally, LepRb induces activation of the JAK2/ERK, /STAT3, /STAT5 and IRS/PI3 kinase signaling cascades, which are important for the regulation of energy homeostasis and appetite in mammals. In this review, we discuss the structure, genetics and distribution of the leptin receptors, and their role in cell signaling mechanisms.

  8. Axonal GABAA receptors.

    Science.gov (United States)

    Trigo, Federico F; Marty, Alain; Stell, Brandon M

    2008-09-01

    Type A GABA receptors (GABA(A)Rs) are well established as the main inhibitory receptors in the mature mammalian forebrain. In recent years, evidence has accumulated showing that GABA(A)Rs are prevalent not only in the somatodendritic compartment of CNS neurons, but also in their axonal compartment. Evidence for axonal GABA(A)Rs includes new immunohistochemical and immunogold data: direct recording from single axonal terminals; and effects of local applications of GABA(A)R modulators on action potential generation, on axonal calcium signalling, and on neurotransmitter release. Strikingly, whereas presynaptic GABA(A)Rs have long been considered inhibitory, the new studies in the mammalian brain mostly indicate an excitatory action. Depending on the neuron that is under study, axonal GABA(A)Rs can be activated by ambient GABA, by GABA spillover, or by an autocrine action, to increase either action potential firing and/or transmitter release. In certain neurons, the excitatory effects of axonal GABA(A)Rs persist into adulthood. Altogether, axonal GABA(A)Rs appear as potent neuronal modulators of the mammalian CNS.

  9. Discoidin Domain Receptor 1

    Science.gov (United States)

    Song, Sunmi; Shackel, Nicholas A.; Wang, Xin M.; Ajami, Katerina; McCaughan, Geoffrey W.; Gorrell, Mark D.

    2011-01-01

    Discoidin domain receptor 1 (DDR1) is a receptor tyrosine kinase that binds and is activated by collagens. Transcriptional profiling of cirrhosis in human liver using a DNA array and quantitative PCR detected elevated mRNA expression of DDR1 compared with that in nondiseased liver. The present study characterized DDR1 expression in cirrhotic and nondiseased human liver and examined the cellular effects of DDR1 expression. mRNA expression of all five isoforms of DDR1 was detected in human liver, whereas DDR1a demonstrated differential expression in liver with hepatitis C virus and primary biliary cirrhosis compared with nondiseased liver. In addition, immunoblot analysis detected shed fragments of DDR1 more readily in cirrhotic liver than in nondiseased liver. Inasmuch as DDR1 is subject to protease-mediated cleavage after prolonged interaction with collagen, this differential expression may indicate more intense activation of DDR1 protein in cirrhotic compared with nondiseased liver. In situ hybridization and immunofluorescence localized intense DDR1 mRNA and protein expression to epithelial cells including hepatocytes at the portal-parenchymal interface and the luminal aspect of the biliary epithelium. Overexpression of DDR1a altered hepatocyte behavior including increased adhesion and less migration on extracelular matrix substrates. DDR1a regulated extracellular expression of matrix metalloproteinases 1 and 2. These data elucidate DDR1 function pertinent to cirrhosis and indicate the importance of epithelial cell–collagen interactions in chronic liver injury. PMID:21356365

  10. Trace amine-associated receptors are olfactory receptors in vertebrates.

    Science.gov (United States)

    Liberles, Stephen D

    2009-07-01

    The mammalian nose is a powerful chemosensor, capable of detecting and distinguishing a myriad of chemicals. Sensory neurons in the olfactory epithelium contain two types of chemosensory G protein-coupled receptors (GPCRs): odorant receptors (ORs), which are encoded by the largest gene family in mammals, and trace amine-associated receptors (TAARs), a smaller family of receptors distantly related to biogenic amine receptors. Do TAARs play a specialized role in olfaction distinct from that of ORs? Genes encoding TAARs are found in diverse vertebrates, from fish to mice to humans. Like OR genes, each Taar gene defines a unique population of canonical sensory neurons dispersed in a single zone of the olfactory epithelium. Ligands for mouse TAARs include a number of volatile amines, several of which are natural constituents of mouse urine, a rich source of rodent social cues. One chemical, 2-phenylethylamine, is reported to be enriched in the urine of stressed animals, and two others, trimethylamine and isoamylamine, are enriched in male versus female urine. Furthermore, isoamylamine has been proposed to be a pheromone that induces puberty acceleration in young female mice. These data raise the possibility that some TAARs are pheromone receptors in the nose, a hypothesis consistent with recent data suggesting that the olfactory epithelium contains dedicated pheromone receptors, separate from pheromone receptors in the vomeronasal organ. Future experiments will clarify the roles of TAARs in olfaction.

  11. GABAB receptors modulate NMDA receptor calcium signals in dendritic spines.

    Science.gov (United States)

    Chalifoux, Jason R; Carter, Adam G

    2010-04-15

    Metabotropic GABA(B) receptors play a fundamental role in modulating the excitability of neurons and circuits throughout the brain. These receptors influence synaptic transmission by inhibiting presynaptic release or activating postsynaptic potassium channels. However, their ability to directly influence different types of postsynaptic glutamate receptors remains unresolved. Here we examine GABA(B) receptor modulation in layer 2/3 pyramidal neurons from the mouse prefrontal cortex. We use two-photon laser-scanning microscopy to study synaptic modulation at individual dendritic spines. Using two-photon optical quantal analysis, we first demonstrate robust presynaptic modulation of multivesicular release at single synapses. Using two-photon glutamate uncaging, we then reveal that GABA(B) receptors strongly inhibit NMDA receptor calcium signals. This postsynaptic modulation occurs via the PKA pathway and does not affect synaptic currents mediated by AMPA or NMDA receptors. This form of GABA(B) receptor modulation has widespread implications for the control of calcium-dependent neuronal function.

  12. Possible Relevance of Receptor-Receptor Interactions between Viral- and Host-Coded Receptors for Viral-Induced Disease

    Directory of Open Access Journals (Sweden)

    Luigi F. Agnati

    2007-01-01

    Full Text Available It has been demonstrated that some viruses, such as the cytomegalovirus, code for G-protein coupled receptors not only to elude the immune system, but also to redirect cellular signaling in the receptor networks of the host cells. In view of the existence of receptor-receptor interactions, the hypothesis is introduced that these viral-coded receptors not only operate as constitutively active monomers, but also can affect other receptor function by interacting with receptors of the host cell. Furthermore, it is suggested that viruses could also insert not single receptors (monomers, but clusters of receptors (receptor mosaics, altering the cell metabolism in a profound way. The prevention of viral receptor-induced changes in host receptor networks may give rise to novel antiviral drugs that counteract viral-induced disease.

  13. Sensory receptors in monotremes.

    Science.gov (United States)

    Proske, U; Gregory, J E; Iggo, A

    1998-01-01

    This is a summary of the current knowledge of sensory receptors in skin of the bill of the platypus, Ornithorhynchus anatinus, and the snout of the echidna, Tachyglossus aculeatus. Brief mention is also made of the third living member of the monotremes, the long-nosed echidna, Zaglossus bruijnii. The monotremes are the only group of mammals known to have evolved electroreception. The structures in the skin responsible for the electric sense have been identified as sensory mucous glands with an expanded epidermal portion that is innervated by large-diameter nerve fibres. Afferent recordings have shown that in both platypuses and echidnas the receptors excited by cathodal (negative) pulses and inhibited by anodal (positive) pulses. Estimates give a total of 40,000 mucous sensory glands in the upper and lower bill of the platypus, whereas there are only about 100 in the tip of the echidna snout. Recording of electroreceptor-evoked activity from the brain of the platypus have shown that the largest area dedicated to somatosensory input from the bill, S1, shows alternating rows of mechanosensory and bimodal neurons. The bimodal neurons respond to both electrosensory and mechanical inputs. In skin of the platypus bill and echidna snout, apart from the electroreceptors, there are structures called push rods, which consist of a column of compacted cells that is able to move relatively independently of adjacent regions of skin. At the base of the column are Merkel cell complexes, known to be type I slowly adapting mechanoreceptors, and lamellated corpuscles, probably vibration receptors. It has been speculated that the platypus uses its electric sense to detect the electromyographic activity from moving prey in the water and for obstacle avoidance. Mechanoreceptors signal contact with the prey. For the echidna, a role for the electrosensory system has not yet been established during normal foraging behaviour, although it has been shown that it is able to detect the presence

  14. Coronavirus spike-receptor interactions

    NARCIS (Netherlands)

    Mou, H.

    2015-01-01

    Coronaviruses cause important diseases in humans and animals. Coronavirus infection starts with the virus binding with its spike proteins to molecules present on the surface of host cells that act as receptors. This spike-receptor interaction is highly specific and determines the virus’ cell, tissue

  15. Hydrocarbon Receptor Pathway in Dogs

    NARCIS (Netherlands)

    Steenbeek, F.G. van; Spee, B.; Penning, L.C.; Kummeling, A.; Gils, I.H.M.; Grinwis, G.C.M.; Leenen, D. van; Holstege, F.C.P.; Vos-Loohuis, M.; Rothuizen, J.; Leegwater, P.A.J.

    2013-01-01

    The aryl hydrocarbon receptor (AHR) mediates biological responses to toxic chemicals. An unexpected role for AHR in vascularization was suggested when mice lacking AHR displayed impaired closure of the ductus venosus after birth, as did knockout mice for aryl hydrocarbon receptor interacting protein

  16. Hydrocarbon Receptor Pathway in Dogs

    NARCIS (Netherlands)

    Steenbeek, F.G. van; Spee, B.; Penning, L.C.; Kummeling, A.; Gils, I.H.M.; Grinwis, G.C.M.; Leenen, D. van; Holstege, F.C.P.; Vos-Loohuis, M.; Rothuizen, J.; Leegwater, P.A.J.

    The aryl hydrocarbon receptor (AHR) mediates biological responses to toxic chemicals. An unexpected role for AHR in vascularization was suggested when mice lacking AHR displayed impaired closure of the ductus venosus after birth, as did knockout mice for aryl hydrocarbon receptor interacting

  17. Purinergic Receptors in Thrombosis and Inflammation

    National Research Council Canada - National Science Library

    Hechler, Béatrice; Gachet, Christian

    2015-01-01

    .... Beyond platelets, these 3 receptors, along with the P2Y2, P2Y6, and P2X7 receptors, constitute the main P2 receptors mediating the proinflammatory effects of nucleotides, which play important roles...

  18. Dopamine Receptors and Parkinson's Disease

    Directory of Open Access Journals (Sweden)

    Shin Hisahara

    2011-01-01

    Full Text Available Parkinson's disease (PD is a progressive extrapyramidal motor disorder. Pathologically, this disease is characterized by the selective dopaminergic (DAergic neuronal degeneration in the substantia nigra. Correcting the DA deficiency in PD with levodopa (L-dopa significantly attenuates the motor symptoms; however, its effectiveness often declines, and L-dopa-related adverse effects emerge after long-term treatment. Nowadays, DA receptor agonists are useful medication even regarded as first choice to delay the starting of L-dopa therapy. In advanced stage of PD, they are also used as adjunct therapy together with L-dopa. DA receptor agonists act by stimulation of presynaptic and postsynaptic DA receptors. Despite the usefulness, they could be causative drugs for valvulopathy and nonmotor complication such as DA dysregulation syndrome (DDS. In this paper, physiological characteristics of DA receptor familyare discussed. We also discuss the validity, benefits, and specific adverse effects of pharmaceutical DA receptor agonist.

  19. Opioids and their peripheral receptors

    Directory of Open Access Journals (Sweden)

    Francesco Amato

    2012-12-01

    Full Text Available The inflammation of peripheral tissues leads the primary afferent neurons, in particular at the cell bodies level located in the DRG (dorsal root ganglia, to an increased synthesis of opioid receptors: determining an “up-regulation”. After that opioid receptors are transported at the level of the nociceptive terminals, they are incorporated into the neuronal membrane becoming functional receptors. The above receptor proteins bind to opioid produced by immune cells or the exogenous ones. This leads to a direct or indirect suppression of the Ca2+ currents induced by TRPV1 or the currents of the Na+, resulting in neuronal reduced excitability and in transmitted signals decrease. The observation that the immune system is able to modulate the pain by ligands that interact with the opioid receptors located on sensory neurons, may have broad implications for the development of innovative and safer pain drugs.

  20. Ryanodine receptor channelopathies

    Science.gov (United States)

    Betzenhauser, Matthew J.

    2010-01-01

    Ryanodine receptors (RyR) are intracellular Ca2+-permeable channels that provide the sarcoplasmic reticulum Ca2+ release required for skeletal and cardiac muscle contractions. RyR1 underlies skeletal muscle contraction, and RyR2 fulfills this role in cardiac muscle. Over the past 20 years, numerous mutations in both RyR isoforms have been identified and linked to skeletal and cardiac diseases. Malignant hyperthermia, central core disease, and catecholaminergic polymorphic ventricular tachycardia have been genetically linked to mutations in either RyR1 or RyR2. Thus, RyR channelopathies are both of interest because they cause significant human diseases and provide model systems that can be studied to elucidate important structure–function relationships of these ion channels. PMID:20179962

  1. The evolution of vertebrate opioid receptors

    OpenAIRE

    Stevens, Craig W.

    2009-01-01

    The proteins that mediate the analgesic and other effects of opioid drugs and endogenous opioid peptides are known as opioid receptors. Opioid receptors consist of a family of four closely-related proteins belonging to the large superfamily of G-protein coupled receptors. The three types of opioid receptors shown unequivocally to mediate analgesia in animal models are the mu (MOR), delta (DOR), and kappa (KOR) opioid receptor proteins. The role of the fourth member of the opioid receptor fami...

  2. Estrogen-related receptor β (ERRβ) - renaissance receptor or receptor renaissance?

    Science.gov (United States)

    Divekar, Shailaja D; Tiek, Deanna M; Fernandez, Aileen; Riggins, Rebecca B

    2016-01-01

    Estrogen-related receptors (ERRs) are founding members of the orphan nuclear receptor (ONR) subgroup of the nuclear receptor superfamily. Twenty-seven years of study have yet to identify cognate ligands for the ERRs, though they have firmly placed ERRα and ERRγ at the intersection of cellular metabolism and oncogenesis. The pace of discovery for novel functions of ERRβ, however, has until recently been somewhat slower than that of its family members. ERRβ has also been largely ignored in summaries and perspectives of the ONR literature. Here, we provide an overview of established and emerging knowledge of ERRβ in mouse, man, and other species, highlighting unique aspects of ERRβ biology that set it apart from the other two estrogen-related receptors, with a focus on the impact of alternative splicing on the structure and function of this receptor.

  3. Stargazin Modulation of AMPA Receptors

    Directory of Open Access Journals (Sweden)

    Sana A. Shaikh

    2016-10-01

    Full Text Available Fast excitatory synaptic signaling in the mammalian brain is mediated by AMPA-type ionotropic glutamate receptors. In neurons, AMPA receptors co-assemble with auxiliary proteins, such as stargazin, which can markedly alter receptor trafficking and gating. Here, we used luminescence resonance energy transfer measurements to map distances between the full-length, functional AMPA receptor and stargazin expressed in HEK293 cells and to determine the ensemble structural changes in the receptor due to stargazin. In addition, we used single-molecule fluorescence resonance energy transfer to study the structural and conformational distribution of the receptor and how this distribution is affected by stargazin. Our nanopositioning data place stargazin below the AMPA receptor ligand-binding domain, where it is well poised to act as a scaffold to facilitate the long-range conformational selection observations seen in single-molecule experiments. These data support a model of stargazin acting to stabilize or select conformational states that favor activation.

  4. Cytokine receptors and hematopoietic differentiation.

    Science.gov (United States)

    Robb, L

    2007-10-15

    Colony-stimulating factors and other cytokines signal via their cognate receptors to regulate hematopoiesis. In many developmental systems, inductive signalling determines cell fate and, by analogy with this, it has been postulated that cytokines, signalling via their cognate receptors, may play an instructive role in lineage specification in hematopoiesis. An alternative to this instructive hypothesis is the stochastic or permissive hypothesis. The latter proposes that commitment to a particular hematopoietic lineage is an event that occurs independently of extrinsic signals. It predicts that the role of cytokines is to provide nonspecific survival and proliferation signals. In this review, we look at the role of cytokine receptor signalling in hematopoiesis and consider the evidence for both hypotheses. Data from experiments that genetically manipulate receptor gene expression in vitro or in vivo are reviewed. Experiments in which cytokine receptors were installed in multipotential cells showed that, in some cases, stimulation with the cognate ligand could lead to alterations in lineage output. The creation of genetically manipulated mouse strains demonstrated that cytokine receptors are required for expansion and survival of single lineages but did not reveal a role in lineage commitment. We conclude that hematopoietic differentiation involves mainly stochastic events, but that cytokine receptors also have some instructive role.

  5. Vascular dopamine-I receptors.

    Science.gov (United States)

    Yasunari, K; Kohno, M; Yokokawa, K; Horio, T; Kano, H; Takeda, T

    1995-06-01

    The modulation of dopamine DA1 receptors of cultured rat renal arterial smooth muscle cells by phorbol ester, glucocorticoid and sodium chloride was studied. The extent of [3H]Sch-23390 binding to phorbol ester-treated cell was increased without any change in the dissociation constant (Kd). At a concentration of 10 nmol/l, the synthetic glucocorticoid dexamethasone increased maximum receptor binding (Bmax) but had no effect on the Kd. 100 mmol/l sodium chloride did not change Bmax, but increased the Kd for DA1 receptor. The production of cAMP in response to DA1 receptor stimulation was enhanced without any change of the adenylate cyclase activity. The glucocorticoid effect on DA1 of arterial smooth muscle cells became apparent after hours of incubation in the presence of the steroid and was significantly inhibited by cycloheximide (10 micrograms/ml) and by the glucocorticoid receptor antagonist RU-38486, indicating that the effect required protein synthesis through glucocorticoid receptors. Treatment of cells with 1 mumol/l dexamethasone for 24 h increased basal and DA1-stimulated adenylate cyclase activity. Basal adenylate cyclase was decreased by sodium chloride in a dose-dependent manner. These results suggest differential control of DA1 receptors on vascular smooth muscle cells by protein kinase C, glucocorticoid or sodium chloride.

  6. Nuclear hormone receptors in podocytes

    Directory of Open Access Journals (Sweden)

    Khurana Simran

    2012-09-01

    Full Text Available Abstract Nuclear receptors are a family of ligand-activated, DNA sequence-specific transcription factors that regulate various aspects of animal development, cell proliferation, differentiation, and homeostasis. The physiological roles of nuclear receptors and their ligands have been intensively studied in cancer and metabolic syndrome. However, their role in kidney diseases is still evolving, despite their ligands being used clinically to treat renal diseases for decades. This review will discuss the progress of our understanding of the role of nuclear receptors and their ligands in kidney physiology with emphasis on their roles in treating glomerular disorders and podocyte injury repair responses.

  7. Quantitative receptor radioautography in the study of receptor-receptor interactions in the nucleus tractus solitarii

    Directory of Open Access Journals (Sweden)

    Fior-Chadi D.R.

    1998-01-01

    Full Text Available The nucleus tractus solitarii (NTS in the dorsomedial medulla comprises a wide range of neuropeptides and biogenic amines. Several of them are related to mechanisms of central blood pressure control. Angiotensin II (Ang II, neuropeptide Y (NPY and noradrenaline (NA are found in the NTS cells, as well as their receptors. Based on this observation we have evaluated the modulatory effect of these peptide receptors on a2-adrenoceptors in the NTS. Using quantitative receptor radioautography, we observed that NPY and Ang II receptors decreased the affinity of a2-adrenoceptors for their agonists in the NTS of the rat. Cardiovascular experiments agreed with the in vitro data. Coinjection of a threshold dose of Ang II or of the NPY agonists together with an ED50 dose of adrenergic agonists such as NA, adrenaline and clonidine counteracted the depressor effect produced by the a2-agonist in the NTS. The results provide evidence for the existence of an antagonistic interaction between Ang II at1 receptors and NPY receptor subtypes with the a2-adrenoceptors in the NTS. This receptor interaction may reduce the transduction over the a2-adrenoceptors which can be important in central cardiovascular regulation and in the development of hypertension

  8. Autoimmune NMDA receptor encephalitis.

    Science.gov (United States)

    Lazar-Molnar, Eszter; Tebo, Anne E

    2015-01-01

    Anti-N-methyl-d-aspartate receptor (anti-NMDAR) encephalitis is a treatable autoimmune disease of the central nervous system (CNS) with prominent neurologic and psychiatric features at disease onset. The disease is associated with the production of autoantibodies to NMDAR, a protein involved in memory function and synaptic plasticity. Affected patients develop a multistage progressive illness with symptoms ranging from memory deficits, seizures and psychosis, to potentially lethal catatonia, and autonomic and breathing instability. The outcome can be much improved with accurate diagnosis and early treatment using adequate immunosuppressive therapy. However, since the neurological and psychiatric symptoms as well as the clinical examination results can be non-specific, the disease is probably under-recognized. Reliable and accurate clinical testing for the identification of NMDAR autoantibodies is crucial for diagnosis, timely treatment selection, and monitoring. Recently, a cell-based indirect immunofluorescent antibody test for the detection of IgG antibodies to NMDAR has become available for diagnostic use. This review highlights the progress and challenges of laboratory testing in the evaluation and management anti-NMDAR encephalitis, and perspectives for the future.

  9. Nuclear Receptor Signaling Atlas (NURSA)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Nuclear Receptor Signaling Atlas (NURSA) is designed to foster the development of a comprehensive understanding of the structure, function, and role in disease...

  10. Anthrax receptors position the spindle.

    Science.gov (United States)

    Minc, Nicolas; Piel, Matthieu

    2013-01-01

    Spindle orientation plays a pivotal role in tissue morphogenesis. An asymmetric anthrax receptor cap is revealed to promote activation of a formin to orient the spindle along the planar cell polarity (PCP) axis in zebrafish dorsal epiblast cells.

  11. [Nucleotide receptors and renal function].

    Science.gov (United States)

    Jankowski, Maciej

    2014-01-01

    Kidney plays a key role in homeostasis of human body. It has heterogenic structure and is characterized by complicated vascular beds and numbers of sympathetic nerves endings. Nucleotides receptors are involved in the regulation of blood flow, a fundamental process for renal function. Plasma is filtrated in renal glomerulus and activity of nucleotides receptors located on cells of glomerular filter modifies the physi- cochemical properties of filter and affects the filtration process. Electrolytes, water and low molecular weight molecules are reabsorbed from tubular fluid or secreted into fluid in proximal and distal tubules. Glomerular filtration rate and activity of tubular processes are regulated via nucleotides receptors by glomerulotubularbalance and tubuloglomerular feedback. Nucleotides receptors are involved in systemic regulation of blood pressure and carbohydrate metabolism.

  12. The lactate receptor, G-protein-coupled receptor 81/hydroxycarboxylic acid receptor 1

    DEFF Research Database (Denmark)

    Morland, Cecilie; Lauritzen, Knut Huso; Puchades, Maja;

    2015-01-01

    We have proposed that lactate is a “volume transmitter” in the brain and underpinned this by showing that the lactate receptor, G-protein-coupled receptor 81 (GPR81, also known as HCA1 or HCAR1), which promotes lipid storage in adipocytes, is also active in the mammalian brain. This includes...... anion channels activated by depolarization. In addition to locally produced lactate, lactate produced by exercising muscle as well as exogenous HCAR1 agonists, e.g., from fruits and berries, might activate the receptor on cerebral blood vessels and brain cells....

  13. An Update on GABAρ Receptors

    OpenAIRE

    Martínez-Delgado, Gustavo; Estrada-Mondragón, Argel; Miledi, Ricardo; Martínez-Torres, Ataúlfo

    2010-01-01

    The present review discusses the functional and molecular diversity of GABAρ receptors. These receptors were originally described in the mammalian retina, and their functional role in the visual pathway has been recently elucidated; however new studies on their distribution in the brain and spinal cord have revealed that they are more spread than originally thought, and thus it will be important to determine their physiological contribution to the GABAergic transmission in other areas of the ...

  14. Lysophospholipid receptors in drug discovery

    OpenAIRE

    Kihara, Yasuyuki; Mizuno, Hirotaka; Chun, Jerold

    2014-01-01

    Lysophospholipids (LPs), including lysophosphatidic acid (LPA), sphingosine 1-phospate (S1P), lysophosphatidylinositol (LPI), and lysophosphatidylserine (LysoPS), are bioactive lipids that transduce signals through their specific cell-surface G protein-coupled receptors, LPA1–6, S1P1–5, LPI1, and LysoPS1–3, respectively. These LPs and their receptors have been implicated in both physiological and pathophysiological processes such as autoimmune diseases, neurodegenerative diseases, fibrosis, p...

  15. Receptor antibodies as novel therapeutics for diabetes

    DEFF Research Database (Denmark)

    Ussar, Siegfried; Vienberg, Sara Gry; Kahn, C Ronald

    2011-01-01

    Antibodies to receptors can block or mimic hormone action. Taking advantage of receptor isoforms, co-receptors, and other receptor modulating proteins, antibodies and other designer ligands can enhance tissue specificity and provide new approaches to the therapy of diabetes and other diseases....

  16. Receptor-targeted metalloradiopharmaceuticals. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Green, Mark A.

    2000-03-22

    Copper (II) and platinum (II) coordination complexes were prepared and characterized. These complexes were designed to afford structural homology with steroidal and non-steroidal estrogens for possible use as receptor-targeted radiopharmaceuticals. While weak affinity for the estrogen receptor was detectable, none would appear to have sufficient receptor-affinity for estrogen-receptor-targeted imaging or therapy.

  17. Estrogen receptors in breast carcinoma.

    Science.gov (United States)

    Huaman, A

    1979-11-01

    On the basis of estrogen receptor assays, breast carcinomas are presently classified as estrogen-dependent tumors, which respond to endocrine therapy, and autonomous tumors, for which endocrine therapy is useless. This paper presents a short review of the biochemical principles of estrogen dependence, the procedures used to determine estrogen receptors, and the clinical applications of the findings of these assay procedures. Biobhemically, the estroogen dependence of normal breast cells is explained as a biochemical reaction occurring between the circulating estradiol and the breast cell, which occurs in 3 steps: 1) circulating estradiol penetrates the cellular membrane by passive diffusion, followed by 2) combining of estradiol with the estrogen-binding protein (estrophilin) and formation of an estrogen receptor complex which undergoes activation and translocation into the nucleus, to result in 3) the activated steroid receptor which combines with the nuclear charomatin and stimulates ribonucleic acid synthesis for the formation of estradiol binding proteins or estradiol receptors. The cytosol method of Wittliff et al. is described in brief and entails radioactive competitive analysis; the other available laboratory procedure is immunofluorescence of tumor sections. Quantification of estrogen receptor content can be used clinically to decide on ablative endocrine therapy, to determine the effectiveness of anti-estrogen administration, to determine the primary site of metastatic carcinoma, and as a screenng device.

  18. Lymphangiogenesis Occurring in Transplanted Corneas

    Institute of Scientific and Technical Information of China (English)

    LING Shiqi; XIAO Qing; HU Yanhua

    2006-01-01

    To study corneal lymphangiogenesis after corneal transplantation, corneal allogenic transplantation models were established in rats. 8 female Wister rats were used as donors, and 16 Sprague Dawley (SD) rats were used as recipients and 2 SD served as controls. Corneal lymphangiogenesis and hemangiogenesis was examined by electron microscopy 1 and 2 weeks after corneal penetrating transplantation, and the expression of lymphatic vessel endothelial receptor (LYVE-1) was examined 1, 3, 7, 14 days after the transplantation respectively. In addition, 19 allograft failed human corneas were examined by 5'-nase-alkaline phosphatase (5'-NA-ALP) doubleenzyme-histochemistry staining to detect corneal lymphangiogenesis and hemangiogenesis. By immunohistochemistry for LYVE-1, it was found that blown lymphatics were localized in the stroma 3days after the corneal transplantation. With electron microscopy, new lymphatic vessels and blood vessels were found 1 and 2 weeks after the corneal transplantation. By 5'-NA-ALP enzyme-histochemistry, corneal hemangiogenesis was found in all allograft failed huma n corneas and 5 of 19(26.3%) cases had developed corneal lymphangiogenesis. It is concluded that corneal lymphangiogenesis is present after corneal transplantation, which may play an important role in allograft rejection.

  19. Nuclear Receptors, RXR, and the Big Bang.

    Science.gov (United States)

    Evans, Ronald M; Mangelsdorf, David J

    2014-03-27

    Isolation of genes encoding the receptors for steroids, retinoids, vitamin D, and thyroid hormone and their structural and functional analysis revealed an evolutionarily conserved template for nuclear hormone receptors. This discovery sparked identification of numerous genes encoding related proteins, termed orphan receptors. Characterization of these orphan receptors and, in particular, of the retinoid X receptor (RXR) positioned nuclear receptors at the epicenter of the "Big Bang" of molecular endocrinology. This Review provides a personal perspective on nuclear receptors and explores their integrated and coordinated signaling networks that are essential for multicellular life, highlighting the RXR heterodimer and its associated ligands and transcriptional mechanism.

  20. Prognostic Value of Estrogen Receptor alpha and Progesterone Receptor Conversion in Distant Breast Cancer Metastases

    NARCIS (Netherlands)

    Hoefnagel, Laurien D. C.; Moelans, Cathy B.; Meijer, S. L.; van Slooten, Henk-Jan; Wesseling, Pieter; Wesseling, Jelle; Westenend, Pieter J.; Bart, Joost; Seldenrijk, Cornelis A.; Nagtegaal, Iris D.; Oudejans, Joost; van der Valk, Paul; van Gils, Carla H.; van der Wall, Elsken; van Diest, Paul J.

    2012-01-01

    BACKGROUND: Changes in the receptor profile of primary breast cancers to their metastases (receptor conversion) have been described for the estrogen receptor alpha (ER alpha) and progesterone receptor (PR). The purpose of this study was to evaluate the impact of receptor conversion for ER alpha and

  1. Neurotrophins and their receptors in inflammation

    Institute of Scientific and Technical Information of China (English)

    NellyFROSSARD; CharlesADVENIER

    2004-01-01

    The neurotrophin family has recently been in volved ininflammatory and remodelling processes occurring in chronic inflammatory diseases, in particular in asthma. Nerve growth fac-tor (NGF) is a high molecular weight peptide that belongs to the neurotrophin family. It is synthesized by various structural and inflammatory cells and activates two types of receptors, the TrkA (tropomyosin-receptor kinase A) receptor and the p75NTR receptor, in the death receptor family. NGF was first studied for

  2. Toll-like receptors in neonatal sepsis.

    LENUS (Irish Health Repository)

    O'Hare, Fiona M

    2013-06-01

    Toll-like receptors are vital transmembrane receptors that initiate the innate immune response to many micro-organisms. The discovery of these receptors has improved our understanding of host-pathogen interactions, and these receptors play an important role in the pathogenesis of multiple neonatal conditions such as sepsis and brain injury. Toll-like receptors, especially TLRs 2 and 4, are associated with necrotizing enterocolitis, periventricular leukomalacia and sepsis.

  3. Phenobarbital and Insulin Reciprocate Activation of the Nuclear Receptor Constitutive Androstane Receptor through the Insulin Receptor.

    Science.gov (United States)

    Yasujima, Tomoya; Saito, Kosuke; Moore, Rick; Negishi, Masahiko

    2016-05-01

    Phenobarbital (PB) antagonized insulin to inactivate the insulin receptor and attenuated the insulin receptor downstream protein kinase B (AKT)-forkhead box protein O1 and extracellular signal-regulated kinase 1/2 signals in mouse primary hepatocytes and HepG2 cells. Hepatic AKT began dephosphorylation in an early stage of PB treatment, and blood glucose levels transiently increased in both wild-type and constitutive androstane receptor (CAR) knockout (KO) mice. On the other hand, blood glucose levels increased in wild-type mice, but not KO mice, in later stages of PB treatment. As a result, PB, acting as an insulin receptor antagonist, elicited CAR-independent increases and CAR-dependent decreases of blood glucose levels at these different stages of treatment, respectively. Reciprocally, insulin activation of the insulin receptor repressed CAR activation and induction of its target CYP2B6 gene in HepG2 cells. Thus, PB and insulin cross-talk through the insulin receptor to regulate glucose and drug metabolism reciprocally.

  4. Purinergic Receptors in Ocular Inflammation

    Directory of Open Access Journals (Sweden)

    Ana Guzman-Aranguez

    2014-01-01

    Full Text Available Inflammation is a complex process that implies the interaction between cells and molecular mediators, which, when not properly “tuned,” can lead to disease. When inflammation affects the eye, it can produce severe disorders affecting the superficial and internal parts of the visual organ. The nucleoside adenosine and nucleotides including adenine mononucleotides like ADP and ATP and dinucleotides such as P1,P4-diadenosine tetraphosphate (Ap4A, and P1,P5-diadenosine pentaphosphate (Ap5A are present in different ocular locations and therefore they may contribute/modulate inflammatory processes. Adenosine receptors, in particular A2A adenosine receptors, present anti-inflammatory action in acute and chronic retinal inflammation. Regarding the A3 receptor, selective agonists like N6-(3-iodobenzyl-5′-N-methylcarboxamidoadenosine (CF101 have been used for the treatment of inflammatory ophthalmic diseases such as dry eye and uveoretinitis. Sideways, diverse stimuli (sensory stimulation, large intraocular pressure increases can produce a release of ATP from ocular sensory innervation or after injury to ocular tissues. Then, ATP will activate purinergic P2 receptors present in sensory nerve endings, the iris, the ciliary body, or other tissues surrounding the anterior chamber of the eye to produce uveitis/endophthalmitis. In summary, adenosine and nucleotides can activate receptors in ocular structures susceptible to suffer from inflammatory processes. This involvement suggests the possible use of purinergic agonists and antagonists as therapeutic targets for ocular inflammation.

  5. Ionotropic glutamate receptors & CNS disorders.

    Science.gov (United States)

    Bowie, Derek

    2008-04-01

    Disorders of the central nervous system (CNS) are complex disease states that represent a major challenge for modern medicine. Although aetilogy is often unknown, it is established that multiple factors such as defects in genetics and/or epigenetics, the environment as well as imbalance in neurotransmitter receptor systems are all at play in determining an individual's susceptibility to disease. Gene therapy is currently not available and therefore, most conditions are treated with pharmacological agents that modify neurotransmitter receptor signaling. Here, I provide a review of ionotropic glutamate receptors (iGluRs) and the roles they fulfill in numerous CNS disorders. Specifically, I argue that our understanding of iGluRs has reached a critical turning point to permit, for the first time, a comprehensive re-evaluation of their role in the cause of disease. I illustrate this by highlighting how defects in AMPA receptor (AMPAR) trafficking are important to fragile X mental retardation and ectopic expression of kainate receptor (KAR) synapses contributes to the pathology of temporal lobe epilepsy. Finally, I discuss how parallel advances in studies of other neurotransmitter systems may allow pharmacologists to work towards a cure for many CNS disorders rather than developing drugs to treat their symptoms.

  6. Brain CB₂ Receptors: Implications for Neuropsychiatric Disorders.

    Science.gov (United States)

    Roche, Michelle; Finn, David P

    2010-08-10

    Although previously thought of as the peripheral cannabinoid receptor, it is now accepted that the CB₂ receptor is expressed in the central nervous system on microglia, astrocytes and subpopulations of neurons. Expression of the CB₂ receptor in the brain is significantly lower than that of the CB₁ receptor. Conflicting findings have been reported on the neurological effects of pharmacological agents targeting the CB₂ receptor under normal conditions. Under inflammatory conditions, CB₂ receptor expression in the brain is enhanced and CB2 receptor agonists exhibit potent anti-inflammatory effects. These findings have prompted research into the CB₂ receptor as a possible target for the treatment of neuroinflammatory and neurodegenerative disorders. Neuroinflammatory alterations are also associated with neuropsychiatric disorders and polymorphisms in the CB₂ gene have been reported in depression, eating disorders and schizophrenia. This review will examine the evidence to date for a role of brain CB₂ receptors in neuropsychiatric disorders.

  7. Identification and mechanism of ABA receptor antagonism

    Energy Technology Data Exchange (ETDEWEB)

    Melcher, Karsten; Xu, Yong; Ng, Ley-Moy; Zhou, X. Edward; Soon, Fen-Fen; Chinnusamy, Viswanathan; Suino-Powell, Kelly M; Kovach, Amanda; Tham, Fook S.; Cutler, Sean R.; Li, Jun; Yong, Eu-Leong; Zhu, Jian-Kang; Xu, H. Eric (NU Sinapore); (Van Andel); (UCR)

    2010-11-11

    The phytohormone abscisic acid (ABA) functions through a family of fourteen PYR/PYL receptors, which were identified by resistance to pyrabactin, a synthetic inhibitor of seed germination. ABA activates these receptors to inhibit type 2C protein phosphatases, such as ABI1, yet it remains unclear whether these receptors can be antagonized. Here we demonstrate that pyrabactin is an agonist of PYR1 and PYL1 but is unexpectedly an antagonist of PYL2. Crystal structures of the PYL2-pyrabactin and PYL1-pyrabactin-ABI1 complexes reveal the mechanism responsible for receptor-selective activation and inhibition, which enables us to design mutations that convert PYL1 to a pyrabactin-inhibited receptor and PYL2 to a pyrabactin-activated receptor and to identify new pyrabactin-based ABA receptor agonists. Together, our results establish a new concept of ABA receptor antagonism, illustrate its underlying mechanisms and provide a rational framework for discovering novel ABA receptor ligands.

  8. Cannabinoids, cannabinoid receptors and tinnitus.

    Science.gov (United States)

    Smith, Paul F; Zheng, Yiwen

    2016-02-01

    One hypothesis suggests that tinnitus is a form of sensory epilepsy, arising partly from neuronal hyperactivity in auditory regions of the brain such as the cochlear nucleus and inferior colliculus. Although there is currently no effective drug treatment for tinnitus, anti-epileptic drugs are used in some cases as a potential treatment option. There is increasing evidence to suggest that cannabinoid drugs, i.e. cannabinoid receptor agonists, can also have anti-epileptic effects, at least in some cases and in some parts of the brain. It has been reported that cannabinoid CB1 receptors and the endogenous cannabinoid, 2-arachidonylglycerol (2-AG), are expressed in the cochlear nucleus and that they are involved in the regulation of plasticity. This review explores the question of whether cannabinoid receptor agonists are likely to be pro- or anti-epileptic in the cochlear nucleus and therefore whether cannabinoids and Cannabis itself are likely to make tinnitus better or worse.

  9. Are olfactory receptors really olfactive?

    DEFF Research Database (Denmark)

    Giorgi, Franco; Maggio, Roberto; Bruni, Luis Emilio

    2011-01-01

    Any living organism interacts with and responds specifically to environmental molecules by expressing specific olfactory receptors. This specificity will be first examined in causal terms with particular emphasis on the mechanisms controlling olfactory gene expression, cell-to-cell interactions...... and odor-decoding processes. However, this type of explanation does not entirely justify the role olfactory receptors have played during evolution, since they are also expressed ectopically in different organs and/or tissues. Homologous olfactory genes have in fact been found in such diverse cells and....../or organs as spermatozoa, testis and kidney where they are assumed to act as chemotactic sensors or renin modulators. To justify their functional diversity, homologous olfactory receptors are assumed to share the same basic role: that of conferring a self-identity to cells or tissues under varying...

  10. An Update on GABAρ Receptors

    Science.gov (United States)

    Martínez-Delgado, Gustavo; Estrada-Mondragón, Argel; Miledi, Ricardo; Martínez-Torres, Ataúlfo

    2010-01-01

    The present review discusses the functional and molecular diversity of GABAρ receptors. These receptors were originally described in the mammalian retina, and their functional role in the visual pathway has been recently elucidated; however new studies on their distribution in the brain and spinal cord have revealed that they are more spread than originally thought, and thus it will be important to determine their physiological contribution to the GABAergic transmission in other areas of the central nervous system. In addition, molecular modeling has revealed peculiar traits of these receptors that have impacted on the interpretations of the latest pharmacolgical and biophysical findings. Finally, sequencing of several vertebrate genomes has permitted a comparative analysis of the organization of the GABAρ genes. PMID:21629448

  11. Cytokine-Leukotriene Receptor Interactions

    Directory of Open Access Journals (Sweden)

    Marek Rola-Pleszczynski

    2007-01-01

    Full Text Available Biochemical and pharmacological studies have identified the structure of leukotrienes, the pathways that lead to their synthesis, and the signaling events they trigger when they interact with their cognate receptors. A privileged interaction exists between these lipid mediators and another group of molecules essential for inflammation and immune modulation, namely, cytokines. Whereas leukotrienes can trigger the synthesis and release of selected cytokines in distinct cell populations, many cytokines can affect cellular responsiveness to leukotrienes by modulating leukotriene receptor expression. As we progressively begin to unravel these complex interactions, new areas of cell-cell communication and eventual therapeutic interventions will emerge.

  12. Nuclear receptors and nonalcoholic fatty liver disease.

    Science.gov (United States)

    Cave, Matthew C; Clair, Heather B; Hardesty, Josiah E; Falkner, K Cameron; Feng, Wenke; Clark, Barbara J; Sidey, Jennifer; Shi, Hongxue; Aqel, Bashar A; McClain, Craig J; Prough, Russell A

    2016-09-01

    Nuclear receptors are transcription factors which sense changing environmental or hormonal signals and effect transcriptional changes to regulate core life functions including growth, development, and reproduction. To support this function, following ligand-activation by xenobiotics, members of subfamily 1 nuclear receptors (NR1s) may heterodimerize with the retinoid X receptor (RXR) to regulate transcription of genes involved in energy and xenobiotic metabolism and inflammation. Several of these receptors including the peroxisome proliferator-activated receptors (PPARs), the pregnane and xenobiotic receptor (PXR), the constitutive androstane receptor (CAR), the liver X receptor (LXR) and the farnesoid X receptor (FXR) are key regulators of the gut:liver:adipose axis and serve to coordinate metabolic responses across organ systems between the fed and fasting states. Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease and may progress to cirrhosis and even hepatocellular carcinoma. NAFLD is associated with inappropriate nuclear receptor function and perturbations along the gut:liver:adipose axis including obesity, increased intestinal permeability with systemic inflammation, abnormal hepatic lipid metabolism, and insulin resistance. Environmental chemicals may compound the problem by directly interacting with nuclear receptors leading to metabolic confusion and the inability to differentiate fed from fasting conditions. This review focuses on the impact of nuclear receptors in the pathogenesis and treatment of NAFLD. Clinical trials including PIVENS and FLINT demonstrate that nuclear receptor targeted therapies may lead to the paradoxical dissociation of steatosis, inflammation, fibrosis, insulin resistance, dyslipidemia and obesity. Novel strategies currently under development (including tissue-specific ligands and dual receptor agonists) may be required to separate the beneficial effects of nuclear receptor activation from unwanted metabolic

  13. Slamf receptors : Modulators of Phagocyte Immune Responses

    NARCIS (Netherlands)

    Van Driel, Boaz Job

    2015-01-01

    Signaling Lymphocyte Activation Molecule family (Slamf) receptors can operate in three distinct modes. Slamf receptors can dictate the extent of immune responses, thereby maneuvering immunity to the optimal zone between immunopathology or autoimmunity and weak, ineffective immune responses. A second

  14. Mechanism for the activation of glutamate receptors

    Science.gov (United States)

    Scientists at the NIH have used a technique called cryo-electron microscopy to determine a molecular mechanism for the activation and desensitization of ionotropic glutamate receptors, a prominent class of neurotransmitter receptors in the brain and spina

  15. Cannabinoid receptor localization in brain

    Energy Technology Data Exchange (ETDEWEB)

    Herkenham, M.; Lynn, A.B.; Little, M.D.; Johnson, M.R.; Melvin, L.S.; de Costa, B.R.; Rice, K.C. (National Institute of Mental Health, Bethesda, MD (USA))

    1990-03-01

    (3H)CP 55,940, a radiolabeled synthetic cannabinoid, which is 10-100 times more potent in vivo than delta 9-tetrahydrocannabinol, was used to characterize and localize a specific cannabinoid receptor in brain sections. The potencies of a series of natural and synthetic cannabinoids as competitors of (3H)CP 55,940 binding correlated closely with their relative potencies in several biological assays, suggesting that the receptor characterized in our in vitro assay is the same receptor that mediates behavioral and pharmacological effects of cannabinoids, including human subjective experience. Autoradiography of cannabinoid receptors in brain sections from several mammalian species, including human, reveals a unique and conserved distribution; binding is most dense in outflow nuclei of the basal ganglia--the substantia nigra pars reticulata and globus pallidus--and in the hippocampus and cerebellum. Generally high densities in forebrain and cerebellum implicate roles for cannabinoids in cognition and movement. Sparse densities in lower brainstem areas controlling cardiovascular and respiratory functions may explain why high doses of delta 9-tetrahydrocannabinol are not lethal.

  16. Are olfactory receptors really olfactive?

    DEFF Research Database (Denmark)

    Giorgi, Franco; Maggio, Roberto; Bruni, Luis Emilio

    2011-01-01

    Any living organism interacts with and responds specifically to environmental molecules by expressing specific olfactory receptors. This specificity will be first examined in causal terms with particular emphasis on the mechanisms controlling olfactory gene expression, cell-to-cell interactions a...

  17. Hormone receptors in breast cancer

    NARCIS (Netherlands)

    Suijkerbuijk, K. P M; van der Wall, E.; van Diest, P. J.

    2016-01-01

    Steroid hormone receptors are critical for the growth and development of breast tissue as well as of breast cancer. The importance of the role estrogens in breast cancer has been delineated for more than 100 years. The analysis of its expression has been used not only to classify breast cancers but

  18. Dopamine Receptor Availability in ADHD

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2002-01-01

    Full Text Available Striatal dopamine (D2 receptor availability was determined by iodobenzamide brain SPECT, before and 3 months after methylphenidate (MPH therapy, in 9 children (mean age, 9.8 years with attention deficit hyperactivity disorder (ADHD examined at Gazi University, Ankara, Turkey.

  19. Emerging GLP-1 receptor agonists

    DEFF Research Database (Denmark)

    Lund, Asger; Knop, Filip K; Vilsbøll, Tina

    2011-01-01

    Introduction: Recently, glucagon-like peptide-1 receptor (GLP-1R) agonists have become available for the treatment of type 2 diabetes. These agents exploit the physiological effects of GLP-1, which is able to address several of the pathophysiological features of type 2 diabetes. GLP-1R agonists...

  20. Serotonin receptors as cardiovascular targets

    NARCIS (Netherlands)

    C.M. Villalón (Carlos); P.A.M. de Vries (Peter); P.R. Saxena (Pramod Ranjan)

    1997-01-01

    textabstractSerotonin exerts complex effects in the cardiovascular system, including hypotension or hypertension, vasodilatation or vasoconstriction, and/or bradycardia or tachycardia; the eventual response depends primarily on the nature of the 5-HT receptors involved. In the light of current 5-HT

  1. Estrogen Receptor Driven Inhibitor Synthesis

    Science.gov (United States)

    2006-09-01

    Engstrom O, Ohman L, Greene GL, Gustaffson JA, Carlquist M. Molecular basis of agonism and antagonism in the oestrogen receptor. Nature 389, 753-758...oxidatively modified proteins in Bacillus subtilis, Mol. Microbiol. 58 (2005) 409–425. [7] K. Tyagarajan, E. Pretzer, J.E. Wiktorowicz, Thiol-reactive dyes

  2. NMDA receptors and memory encoding.

    Science.gov (United States)

    Morris, Richard G M

    2013-11-01

    It is humbling to think that 30 years have passed since the paper by Collingridge, Kehl and McLennan showing that one of Jeff Watkins most interesting compounds, R-2-amino-5-phosphonopentanoate (d-AP5), blocked the induction of long-term potentiation in vitro at synapses from area CA3 of the hippocampus to CA1 without apparent effect on baseline synaptic transmission (Collingridge et al., 1983). This dissociation was one of the key triggers for an explosion of interest in glutamate receptors, and much has been discovered since that collectively contributes to our contemporary understanding of glutamatergic synapses - their biophysics and subunit composition, of the agonists and antagonists acting on them, and their diverse functions in different networks of the brain and spinal cord. It can be fairly said that Collingridge et al.'s (1983) observation was the stimulus that has led, on the one hand, to structural biological work at the atomic scale describing the key features of NMDA receptors that enables their coincidence function to happen; and, on the other, to work with whole animals investigating the contributions that calcium signalling via this receptor can have on rhythmical activities controlled by spinal circuits, memory encoding in the hippocampus (the topic of this article), visual cortical plasticity, sensitization in pain, and other functions. In this article, I lay out how my then interest in long-term potentiation (LTP) as a model of memory enabled me to recognise the importance of Collingridge et al.'s discovery - and how I and my colleagues endeavoured to take things forward in the area of learning and memory. This is in some respects a personal story, and I tell it as such. The idea that NMDA receptor activation is essential for memory encoding, though not for storage, took time to develop and to be accepted. Along the way, there have been confusions, challenges, and surprises surrounding the idea that activation of NMDA receptors can

  3. Amide-based Fluorescent Macrocyclic Anion Receptors

    Institute of Scientific and Technical Information of China (English)

    ZENG, Zhen-Ya(曾振亚); XU, Kuo-Xi(徐括喜); HE, Yong-Bing(何永炳); LIU, Shun-Ying(刘顺英); WU, Jin-Long(吴进龙); WEI, Lan-Hua(隗兰华); MENG, Ling-Zhi(孟令芝)

    2004-01-01

    Two fluorescent anion receptors (1 and 2) based on amide macrocycle were synthesized and corresponding fluorescence quenching induced by anion complexation was observed in different degree. Receptors form 1: 1 complexes with anions by hydrogen bonding interactions. Receptor 1 bound anions in the order of F->Cl->H2PO4->CH3COO->>Br-, I- and receptor 2 showed high selectivity to F- over other anions.

  4. Endogenous ion channel complexes: the NMDA receptor.

    Science.gov (United States)

    Frank, René A W

    2011-06-01

    Ionotropic receptors, including the NMDAR (N-methyl-D-aspartate receptor) mediate fast neurotransmission, neurodevelopment, neuronal excitability and learning. In the present article, the structure and function of the NMDAR is reviewed with the aim to condense our current understanding and highlight frontiers where important questions regarding the biology of this receptor remain unanswered. In the second part of the present review, new biochemical and genetic approaches for the investigation of ion channel receptor complexes will be discussed.

  5. Neuroexcitatory Drug Receptors in Mammals and Invertebrates

    Science.gov (United States)

    1990-03-16

    several animal species investigated. We identified the codfish as having a single polypeptide/gene for CABA -A receptors, as compared to 10-15 different...through blocking of CABA receptor functions. The CABA receptor-chloride channel system is important in wide-spread regions of the mammalian nervous... CABA receptor distribution was quantitated and mapped (14). For this analysis, we employed an image analyzer purchased by Drs. Olsen and de Vellis under

  6. Benzodiazepine receptor antagonists for hepatic encephalopathy

    DEFF Research Database (Denmark)

    Als-Nielsen, B; Gluud, L L; Gluud, C

    2004-01-01

    Hepatic encephalopathy may be associated with accumulation of substances that bind to a receptor-complex in the brain resulting in neural inhibition. Benzodiazepine receptor antagonists may have a beneficial effect on patients with hepatic encephalopathy.......Hepatic encephalopathy may be associated with accumulation of substances that bind to a receptor-complex in the brain resulting in neural inhibition. Benzodiazepine receptor antagonists may have a beneficial effect on patients with hepatic encephalopathy....

  7. Mannose receptor-targeted vaccines.

    Science.gov (United States)

    Keler, Tibor; Ramakrishna, Venky; Fanger, Michael W

    2004-12-01

    Targeting antigens to endocytic receptors on professional antigen-presenting cells (APCs) represents an attractive strategy to enhance the efficacy of vaccines. Such APC-targeted vaccines have an exceptional ability to guide exogenous protein antigens into vesicles that efficiently process the antigen for major histocompatibility complex class I and class II presentation. Efficient targeting not only requires high specificity for the receptor that is abundantly expressed on the surface of APCs, but also the ability to be rapidly internalised and loaded into compartments that contain elements of the antigen-processing machinery. The mannose receptor (MR) and related C-type lectin receptors are particularly designed to sample antigens (self and non-self), much like pattern recognition receptors, to integrate the innate with adaptive immune responses. In fact, a variety of approaches involving delivery of antigens to the MR have demonstrated effective induction of potent cellular and humoral immune responses. Yet, although several lines of evidence in diverse experimental systems attest to the efficacy of targeted vaccine strategies, it is becoming increasingly clear that additional signals, such as those afforded by adjuvants, may be critical to elicit sustained immunity. Therefore, MR-targeted vaccines are likely to be most efficacious in vivo when combined with agents that elicit complementary activation signals. Certainly, a better understanding of the mechanism associated with the induction of immune responses as a result of targeting antigens to the MR, will be important in exploiting MR-targeted vaccines not only for mounting immune defenses against cancer and infectious disease, but also for specific induction of tolerance in the treatment of autoimmune disease.

  8. Repeated blockade of mineralocorticoid receptors, but not of glucocorticoid receptors impairs food rewarded spatial learning

    NARCIS (Netherlands)

    Douma, BRK; Korte, SM; Buwalda, B; la Fleur, SE; Bohus, B; Luiten, PGM

    1998-01-01

    Corticosteroids from the adrenal cortex influence a variety of behaviours including cognition, learning and memory. These hormones act via two intracellular receptors, the mineralo-corticoid receptor (MR) and the glucocorticoid receptor (GR). These two receptor types display a high concentration and

  9. Repeated blockade of mineralocorticoid receptors, but not of glucocorticoid receptors impairs food rewarded spatial learning

    NARCIS (Netherlands)

    Douma, B.R.; Korte, S.M.; Buwalda, B.; Fleur, la S.E.; Bohus, B.; Luiten, P.G.

    1998-01-01

    Corticosteroids from the adrenal cortex influence a variety of behaviours including cognition, learning and memory. These hormones act via two intracellular receptors, the mineralo-corticoid receptor (MR) and the glucocorticoid receptor (GR). These two receptor types display a high concentration and

  10. The brain mineralocorticoid receptor and stress resilience

    NARCIS (Netherlands)

    ter Heegde, Freija; De Rijk, Roel H.; Vinkers, Christiaan H.

    2015-01-01

    Stress exposure activates the HPA-axis and results in the release of corticosteroids which bind to two receptor types in the brain: the mineralocorticoid receptor (MR) and the glucocorticoid receptor (GR). While the role of the GR in stress reactivity has been extensively studied, the MR has receive

  11. The brain mineralocorticoid receptor and stress resilience

    NARCIS (Netherlands)

    ter Heegde, Freija; De Rijk, Roel H.; Vinkers, Christiaan H.

    Stress exposure activates the HPA-axis and results in the release of corticosteroids which bind to two receptor types in the brain: the mineralocorticoid receptor (MR) and the glucocorticoid receptor (GR). While the role of the GR in stress reactivity has been extensively studied, the MR has

  12. Chapter 8. Activation mechanisms of chemokine receptors

    DEFF Research Database (Denmark)

    Jensen, Pia C; Rosenkilde, Mette M

    2009-01-01

    Chemokine receptors belong to the large family of 7-transmembrane (7TM) G-protein-coupled receptors. These receptors are targeted and activated by a variety of different ligands, indicating that activation is a result of similar molecular mechanisms but not necessarily similar modes of ligand bin...

  13. Imaging of receptors in clinical neurosciences

    NARCIS (Netherlands)

    Korf, J

    This article deals with the question why should one determine receptors in the brain with positron and single photon emission tomography (PET and SPECT, respectively). Radiopharmaceuticals for a wide variety of receptors are available now. Receptors studies with PET and SPECT have thus far focused

  14. A new family of insect tyramine receptors

    DEFF Research Database (Denmark)

    Cazzamali, Giuseppe; Klærke, Dan Arne; Grimmelikhuijzen, Cornelis J P

    2005-01-01

    in the genomic databases from the malaria mosquito Anopheles gambiae and the honeybee Apis mellifera. These four tyramine or tyramine-like receptors constitute a new receptor family that is phylogenetically distinct from the previously identified insect octopamine/tyramine receptors. The Drosophila tyramine...

  15. Estrogen receptors in human vaginal tissue

    NARCIS (Netherlands)

    Wiegerinck, M.A.H.M.; Poortman, J.; Agema, A.R.; Thijssen, J.H.H.

    1980-01-01

    The presence of specific estrogen receptors could be demonstrated in vaginal tissue, obtained during operation from 38 women, age 27–75 yr. In 23 premenopausal women the receptor concentration in the vaginal tissue varied between 12 and 91 fmol/mg protein, no significant difference in the receptor

  16. The Human Laminin Receptor is a Member of the Integrin Family of Cell Adhesion Receptors

    Science.gov (United States)

    Gehlsen, Kurt R.; Dillner, Lena; Engvall, Eva; Ruoslahti, Erkki

    1988-09-01

    A receptor for the adhesive basement membrane protein, laminin, was isolated from human glioblastoma cells by affinity chromatography on laminin. This receptor has a heterodimeric structure similar to that of receptors for other extracellular matrix proteins such as fibronectin and vitronectin. Incorporation of the laminin receptor into liposomal membranes makes it possible for liposomes to attach to surfaces coated with laminin. The receptor liposomes also attached to some extent to surfaces coated with fibronectin, but not with other matrix proteins. These properties identify the laminin receptor as a member of the integrin family of cell adhesion receptors.

  17. Activation of Neuropeptide FF Receptors by Kisspeptin Receptor Ligands.

    Science.gov (United States)

    Oishi, Shinya; Misu, Ryosuke; Tomita, Kenji; Setsuda, Shohei; Masuda, Ryo; Ohno, Hiroaki; Naniwa, Yousuke; Ieda, Nahoko; Inoue, Naoko; Ohkura, Satoshi; Uenoyama, Yoshihisa; Tsukamura, Hiroko; Maeda, Kei-Ichiro; Hirasawa, Akira; Tsujimoto, Gozoh; Fujii, Nobutaka

    2011-01-13

    Kisspeptin is a member of the RFamide neuropeptide family that is implicated in gonadotropin secretion. Because kisspeptin-GPR54 signaling is implicated in the neuroendocrine regulation of reproduction, GPR54 ligands represent promising therapeutic agents against endocrine secretion disorders. In the present study, the selectivity profiles of GPR54 agonist peptides were investigated for several GPCRs, including RFamide receptors. Kisspeptin-10 exhibited potent binding and activation of neuropeptide FF receptors (NPFFR1 and NPFFR2). In contrast, short peptide agonists bound with much lower affinity to NPFFRs while showing relatively high selectivity toward GPR54. The possible localization of secondary kisspeptin targets was also demonstrated by variation in the levels of GnRH release from the median eminence and the type of GPR54 agonists used. Negligible affinity of the reported NPFFR ligands to GPR54 was observed and indicates the unidirectional cross-reactivity between both ligands.

  18. Venus Kinase Receptors: prospects in signalling and biological functions of these invertebrate receptors

    OpenAIRE

    Colette eDissous; Marion eMorel; Mathieu eVanderstraete

    2014-01-01

    Venus Kinase Receptors (VKRs) form a family of invertebrate receptor tyrosine kinases (RTKs) initially discovered in the parasitic platyhelminth Schistosoma mansoni. VKRs are single transmembrane receptors which contain an extracellular Venus Flytrap (VFT) structure similar to the ligand binding domain of G Protein Coupled Receptors of class C, and an intracellular Tyrosine Kinase domain close to that of Insulin Receptors. VKRs are found in a large variety of invertebrates from cnidarians to ...

  19. Discoidin Domain Receptors Role in Human Diseases

    Directory of Open Access Journals (Sweden)

    Iker BADIOLA

    2011-11-01

    Full Text Available Discoidin Domain Receptor 1 and Discodin Domain Receptor 2 are the two only members of the DDR family. The DDR family is a Tyrosine Kinase Receptor (TKR family with some peculiarities compared with other Tyrosine Kinase Receptors such as their natural ligand; which in this case is the fibrillar collagen; or the slow phosphorylation pattern. These peculiarities confer a special role to the receptors present in many diseases development processes as cancer, cirrhosis or lung fibrosis. In this review it is described the overview of the DDRs structure and their role in the different disease development and the possibility to consider them as therapeutic targets.

  20. Novel receptors for bacterial protein toxins.

    Science.gov (United States)

    Schmidt, Gudula; Papatheodorou, Panagiotis; Aktories, Klaus

    2015-02-01

    While bacterial effectors are often directly introduced into eukaryotic target cells by various types of injection machines, toxins enter the cytosol of host cells from endosomal compartments or after retrograde transport via Golgi from the ER. A first crucial step of toxin-host interaction is receptor binding. Using optimized protocols and new methods novel toxin receptors have been identified, including metalloprotease ADAM 10 for Staphylococcus aureus α-toxin, laminin receptor Lu/BCAM for Escherichia coli cytotoxic necrotizing factor CNF1, lipolysis stimulated lipoprotein receptor (LSR) for Clostridium difficile transferase CDT and low-density lipoprotein receptor-related protein (LRP) 1 for Clostridium perfringens TpeL toxin.

  1. Evolutionary vignettes of natural killer cell receptors.

    Science.gov (United States)

    Sambrook, Jennifer G; Beck, Stephan

    2007-10-01

    The discovery of novel immune receptors has led to a recent renaissance of research into the innate immune system, following decades of intense research of the adaptive immune system. Of particular interest has been the discovery of the natural killer (NK) cell receptors which, depending on type, interact with classical or non-classical MHC class I antigens of the adaptive immune system, thus functioning at the interface of innate and adaptive immunity. Here, we review recent progress with respect to two such families of NK receptors, the killer immunoglobulin-like receptors (KIRs) and the killer cell lectin-like receptors (KLRs), and attempt to trace their evolution across vertebrates.

  2. Sugars, Sweet Taste Receptors, and Brain Responses.

    Science.gov (United States)

    Lee, Allen A; Owyang, Chung

    2017-06-24

    Sweet taste receptors are composed of a heterodimer of taste 1 receptor member 2 (T1R2) and taste 1 receptor member 3 (T1R3). Accumulating evidence shows that sweet taste receptors are ubiquitous throughout the body, including in the gastrointestinal tract as well as the hypothalamus. These sweet taste receptors are heavily involved in nutrient sensing, monitoring changes in energy stores, and triggering metabolic and behavioral responses to maintain energy balance. Not surprisingly, these pathways are heavily regulated by external and internal factors. Dysfunction in one or more of these pathways may be important in the pathogenesis of common diseases, such as obesity and type 2 diabetes mellitus.

  3. Differences in the interaction of acetylcholine receptor antibodies with receptor from normal, denervated and myasthenic human muscle.

    OpenAIRE

    Lefvert, A. K.

    1982-01-01

    The interaction of acetylcholine receptor antibodies with different kinds of human skeletal muscle receptor was investigated. The reaction of most receptor antibodies was strongest with receptor from a patient with myasthenia gravis and with receptor from denervated muscle. Results obtained with these receptors were well correlated. The binding of most receptor antibodies to receptor from functionally normal muscle was much weaker and also qualitatively different. In a few patients with moder...

  4. Receptor arrays optimized for natural odor statistics.

    Science.gov (United States)

    Zwicker, David; Murugan, Arvind; Brenner, Michael P

    2016-05-17

    Natural odors typically consist of many molecules at different concentrations. It is unclear how the numerous odorant molecules and their possible mixtures are discriminated by relatively few olfactory receptors. Using an information theoretic model, we show that a receptor array is optimal for this task if it achieves two possibly conflicting goals: (i) Each receptor should respond to half of all odors and (ii) the response of different receptors should be uncorrelated when averaged over odors presented with natural statistics. We use these design principles to predict statistics of the affinities between receptors and odorant molecules for a broad class of odor statistics. We also show that optimal receptor arrays can be tuned to either resolve concentrations well or distinguish mixtures reliably. Finally, we use our results to predict properties of experimentally measured receptor arrays. Our work can thus be used to better understand natural olfaction, and it also suggests ways to improve artificial sensor arrays.

  5. Targeting Nuclear Receptors with Marine Natural Products

    Directory of Open Access Journals (Sweden)

    Chunyan Yang

    2014-01-01

    Full Text Available Nuclear receptors (NRs are important pharmaceutical targets because they are key regulators of many metabolic and inflammatory diseases, including diabetes, dyslipidemia, cirrhosis, and fibrosis. As ligands play a pivotal role in modulating nuclear receptor activity, the discovery of novel ligands for nuclear receptors represents an interesting and promising therapeutic approach. The search for novel NR agonists and antagonists with enhanced selectivities prompted the exploration of the extraordinary chemical diversity associated with natural products. Recent studies involving nuclear receptors have disclosed a number of natural products as nuclear receptor ligands, serving to re-emphasize the translational possibilities of natural products in drug discovery. In this review, the natural ligands of nuclear receptors will be described with an emphasis on their mechanisms of action and their therapeutic potentials, as well as on strategies to determine potential marine natural products as nuclear receptor modulators.

  6. How calcium makes endocytic receptors attractive

    DEFF Research Database (Denmark)

    Andersen, Christian B F; Moestrup, Søren K

    2014-01-01

    Nutrients, biological waste-products, toxins, pathogens, and other ligands for endocytosis are typically captured by multidomain receptors with multiligand specificity. Upon internalization, the receptor-ligand complex segregates, followed by lysosomal degradation of the ligand and recycling...... of the receptor. Endosomal acidification and calcium efflux lead to the essential ligand-receptor affinity switch and separation. Recent data, including crystal structures of receptor-ligand complexes, now reveal how calcium, in different types of domain scaffolds, functions in a common way as a removable...... 'lynchpin' that stabilizes favorable positioning of ligand-attractive receptor residues. In addition to explaining how calcium depletion can cause ligand-receptor dissociation, the new data add further insight into how acidification contributes to dissociation through structural changes that affect...

  7. Receptor arrays optimized for natural odor statistics

    CERN Document Server

    Zwicker, David; Brenner, Michael P

    2016-01-01

    Natural odors typically consist of many molecules at different concentrations. It is unclear how the numerous odorant molecules and their possible mixtures are discriminated by relatively few olfactory receptors. Using an information-theoretic model, we show that a receptor array is optimal for this task if it achieves two possibly conflicting goals: (i) each receptor should respond to half of all odors and (ii) the response of different receptors should be uncorrelated when averaged over odors presented with natural statistics. We use these design principles to predict statistics of the affinities between receptors and odorant molecules for a broad class of odor statistics. We also show that optimal receptor arrays can be tuned to either resolve concentrations well or distinguish mixtures reliably. Finally, we use our results to predict properties of experimentally measured receptor arrays. Our work can thus be used to better understand natural olfaction and it also suggests ways to improve artificial sensor...

  8. Glutamate Receptor Aptamers and ALS

    Science.gov (United States)

    2009-01-01

    proposed, including oxidative stress, excitotoxicity, mitochondrial dysfunction, etc., the cause(s) of the disease, including the pathogenesis of the...GluR6-Selective Aptamers for Potential Autism Therapy This project is to develop RNA aptamers against a GluR6 kainate receptor mutant thought to be...involved in autism . Role: PI Department of Defense (PI: Niu) 4/1/09-3/30/14 Advanced Tech./Therapeutic Develop. Grant Developing Biostable

  9. The vanilloid receptor and hypertension

    Institute of Scientific and Technical Information of China (English)

    Donna H WANG

    2005-01-01

    Mammalian transient receptor potential (TRP) channels consist of six related protein sub-families that are involved in a variety of pathophysiological function, and disease development. The TRPV1 channel, a member of the TRPV sub-family, is identified by expression cloning using the "hot" pepper-derived vanilloid compound capsaicin as a ligand. Therefore, TRPV1 is also referred as the vanilloid receptor (VR1) or the capsaicin receptor. VR1 is mainly expressed in a subpopulation of primary afferent neurons that project to cardiovascular and renal tissues.These capsaicin-sensitive primary afferent neurons are not only involved in the perception of somatic and visceral pain, but also have a "sensory-effector" function.Regarding the latter, these neurons release stored neuropeptides through a calcium-dependent mechanism via the binding of capsaicin to VR1. The most studied sensory neuropeptides are calcitonin gene-related peptide (CGRP) and substance P (SP), which are potent vasodilators and natriuretic/diuretic factors. Recent evidence using the model of neonatal degeneration of capsaicin-sensitive sensory nerves revealed novel mechanisms that underlie increased salt sensitivity and several experimental models of hypertension. These mechanisms include insufficient suppression of plasma renin activity and plasma aldosterone levels subsequent to salt loading, enhancement of sympathoexcitatory response in the face of a salt challenge, activation of the endothelin- 1 receptor, and impaired natriuretic response to salt loading in capsaicin-pretreated rats. These data indicate that sensory nerves counterbalance the prohypertensive effects of several neurohormonal systems to maintain normal blood pressure when challenged with salt loading. The therapeutic utilities of vanilloid compounds, endogenous agonists,and sensory neuropeptides are also discussed.

  10. Endomorphins interact with tachykinin receptors.

    Science.gov (United States)

    Kosson, Piotr; Bonney, Iwona; Carr, Daniel B; Lipkowski, Andrzej W

    2005-09-01

    Soon after the discovery of endomorphins several studies indicated differences between pharmacological effects of endomorphins and other MOR selective ligands, as well as differences between the effects of endomorphin I and endomorphin II. We now propose that these differences are the result of an additional non-opioid property of endomorphins, namely, their weak antagonist properties with respect to tachykinin NK1 and NK1 receptors.

  11. The Laminins and their Receptors

    OpenAIRE

    Ferletta, Maria

    2002-01-01

    Basement membranes are thin extracellular sheets that surround muscle, fat and peripheral nerve cells and underlay epithelial and endothelial cells. Laminins are one of the main protein families of these matrices. Integrins and dystroglycan are receptors for laminins, connecting cells to basement membranes. Each laminin consists of three different chains, (α, β, γ). Laminin-1 (α1β1γ1) was the first laminin to be found and is the most frequently studied. Despite this, it was unclear where its ...

  12. Nitrosamines as nicotinic receptor ligands

    OpenAIRE

    Schuller, Hildegard M

    2007-01-01

    Nitrosamines are carcinogens formed in the mammalian organism from amine precursors contained in food, beverages, cosmetics and drugs. The potent carcinogen, NNK, and the weaker carcinogen, NNN, are nitrosamines formed from nicotine. Metabolites of the nitrosamines react with DNA to form adducts responsible for genotoxic effects. We have identified NNK as a high affinity agonist for the alpha7 nicotinic acetylcholine receptor (α7nAChR) whereas NNN bound with high affinity to epibatidine-sensi...

  13. CB receptor ligands from plants.

    Science.gov (United States)

    Woelkart, Karin; Salo-Ahen, Outi M H; Bauer, Rudolf

    2008-01-01

    Advances in understanding the physiology and pharmacology of the endogenous cannabinoid system have potentiated the interest of cannabinoid receptors as potential therapeutic targets. Cannabinoids have been shown to modulate a variety of immune cell functions and have therapeutic implications on central nervous system (CNS) inflammation, chronic inflammatory conditions such as arthritis, and may be therapeutically useful in treating autoimmune conditions such as multiple sclerosis. Many of these drug effects occur through cannabinoid receptor signalling mechanisms and the modulation of cytokines and other gene products. Further, endocannabinoids have been found to have many physiological and patho-physiological functions, including mood alteration and analgesia, control of energy balance, gut motility, motor and co-ordination activities, as well as alleviation of neurological, psychiatric and eating disorders. Plants offer a wide range of chemical diversity and have been a growing domain in the search for effective cannabinoid ligands. Cannabis sativa L. with the known plant cannabinoid, Delta(9-)tetrahydrocannabinol (THC) and Echinacea species with the cannabinoid (CB) receptor-binding lipophilic alkamides are the best known herbal cannabimimetics. This review focuses on the state of the art in CB ligands from plants, as well their possible therapeutic and immunomodulatory effects.

  14. Autophagy selectivity through receptor clustering

    Science.gov (United States)

    Rutenberg, Andrew; Brown, Aidan

    Substrate selectivity in autophagy requires an all-or-none cellular response. We focus on peroxisomes, for which autophagy receptor proteins NBR1 and p62 are well characterized. Using computational models, we explore the hypothesis that physical clustering of autophagy receptor proteins on the peroxisome surface provides an appropriate all-or-none response. We find that larger peroxisomes nucleate NBR1 clusters first, and lose them due to competitive coarsening last, resulting in significant size-selectivity. We then consider a secondary hypothesis that p62 inhibits NBR1 cluster formation. We find that p62 inhibition enhances size-selectivity enough that, even if there is no change of the pexophagy rate, the volume of remaining peroxisomes can significantly decrease. We find that enhanced ubiquitin levels suppress size-selectivity, and that this effect is more pronounced for individual peroxisomes. Sufficient ubiquitin allows receptor clusters to form on even the smallest peroxisomes. We conclude that NBR1 cluster formation provides a viable physical mechanism for all-or-none substrate selectivity in pexophagy. We predict that cluster formation is associated with significant size-selectivity. Now at Simon Fraser University.

  15. [Anti-NMDA-receptor encephalitis].

    Science.gov (United States)

    Engen, Kristine; Agartz, Ingrid

    2016-06-01

    BACKGROUND In 2007 a clinical disease caused by autoantibodies directed against the N-methyl-D-aspartate (NMDA) receptor was described for the first time. Anti-NMDA-receptor encephalitis is a subacute, autoimmune neurological disorder with psychiatric manifestations. The disease is a form of limbic encephalitis and is often paraneoplastic. The condition is also treatable. In this review article we examine the development of the disease, clinical practice, diagnostics and treatment.MATERIAL AND METHOD The article is based on references retrieved from searches in PubMed, and a discretionary selection of articles from the authors' own literature archive.RESULTS The disease most frequently affects young women. It may initially be perceived as a psychiatric condition, as it usually presents in the form of delusions, hallucinations or mania. The diagnosis should be suspected in patients who later develop neurological symptoms such as various movement disorders, epileptic seizures and autonomic instability. Examination of serum or cerebrospinal fluid for NMDA receptor antibodies should be included in the assessment of patients with suspected encephalitis. MRI, EEG and assessment for tumours are important tools in diagnosing the condition and any underlying malignancy.INTERPRETATION If treatment is initiated early, the prognosis is good. Altogether 75 % of patients will fully recover or experience significant improvement. Apart from surgical resection of a possible tumour, the treatment consists of immunotherapy. Because of good possibilities for treatment, it is important that clinicians, particularly those in acute psychiatry, are aware of and alert to this condition.

  16. Presynaptic inhibition by kainate receptors converges mechanistically with presynaptic inhibition by adenosine and GABAB receptors.

    Science.gov (United States)

    Partovi, Dara; Frerking, Matthew

    2006-11-01

    Kainate receptors are widely reported to regulate the release of neurotransmitter in the CNS, but the mechanisms involved remain controversial. Previous studies have found that the kainate receptor agonist ATPA, which selectively activates Glu(K5)-containing kainate receptors, depresses glutamate release at Schaffer-collateral synapses in the hippocampus. In the present study, we provide pharmacological evidence that this depressant effect is mediated by Glu(K5)-containing heteromers, but is distinct from a similar depressant effect engaged by the kainate receptor agonist domoate. The depressant effect of ATPA is insensitive to antagonists for GABA(A), GABA(B), and adenosine receptors, and is also unaffected by lowering the release probability by reducing extracellular calcium. However, the effect of ATPA is partly occluded by prior activation of GABA(B) receptors and completely occluded by prior activation of adenosine receptors, suggesting a mechanistic convergence of heteromeric Glu(K5) kainate receptor signaling with GABA(B) receptors and adenosine receptors. The effects of domoate are partially occluded by both adenosine and GABA(B) receptor agonists, indicating at least a partial convergence of Glu(K5)-lacking kainate receptor signaling with these other pathways. The depressant effect of ATPA is not blocked by inhibition of serine/threonine protein kinases. These results suggest that ATPA and domoate inhibit glutamate release through mechanisms that converge with those of classical metabotropic receptor agonists, although they do so through different receptors.

  17. Receptor response in Venus's fly-trap.

    Science.gov (United States)

    Jacobson, S L

    1965-09-01

    The insect-trapping movement of the plant Dionaea muscipula (Venus's fly-trap) is mediated by the stimulation of mechanosensory hairs located on the surface of the trap. It is known that stimulation of the hairs is followed by action potentials which are propagated over the surface of the trap. It has been reported that action potentials always precede trap closure. The occurrence of non-propagated receptor potentials is reported here. Receptor potentials always precede the action potentials. The receptor potential appears to couple the mechanical stimulation step to the action potential step of the preying sequence. Receptor potentials elicited by mechanical stimulation of a sensory hair were measured by using the hair as an integral part of the current-measuring path. The tip of the hair was cut off exposing the medullary tissue; this provided a natural extension of the measuring electrode into the receptor region at the base of the hair. A measuring pipette electrode was slipped over the cut tip of the hair. Positive and negative receptor potentials were measured. Evidence is presented which supports the hypothesis that the positive and negative receptor potentials originate from independent sources. An analysis is made of (a) the relation of the parameters of mechanical stimuli to the magnitude of the receptor potential, and (b) the relation of the receptor potentials to the action potential. The hypothesis that the positive receptor potential is the generator of the action potential is consistent with these data.

  18. Constitutive receptor systems for drug discovery.

    Science.gov (United States)

    Chen, G; Jayawickreme, C; Way, J; Armour, S; Queen, K; Watson, C; Ignar, D; Chen, W J; Kenakin, T

    1999-12-01

    This paper discusses the use of constitutively active G-protein-coupled receptor systems for drug discovery. Specifically, the ternary complex model is used to define the two major theoretical advantages of constitutive receptor screening-namely, the ability to detect antagonists as well as agonists directly and the fact that constitutive systems are more sensitive to agonists. In experimental studies, transient transfection of Chinese hamster ovary cyclic AMP response element (CRE) luciferase reporter cells with cDNA for human parathyroid hormone receptor, glucagon receptor, and glucagon-like peptide (GLP-1) receptor showed cDNA concentration-dependent constitutive activity with parathyroid hormone (PTH-1) and glucagon. In contrast, no constitutive activity was observed for GLP-1 receptor, yet responses to GLP-1 indicated that receptor expression had taken place. In another functional system, Xenopus laevi melanophores transfected with cDNA for human calcitonin receptor showed constitutive activity. Nine ligands for the calcitonin receptor either increased or decreased constitutive activity in this assay. The sensitivity of the system to human calcitonin increased with increasing constitutive activity. These data indicate that, for those receptors which naturally produce constitutive activity, screening in this mode could be advantageous over other methods.

  19. Protein Connectivity in Chemotaxis Receptor Complexes.

    Directory of Open Access Journals (Sweden)

    Stephan Eismann

    2015-12-01

    Full Text Available The chemotaxis sensory system allows bacteria such as Escherichia coli to swim towards nutrients and away from repellents. The underlying pathway is remarkably sensitive in detecting chemical gradients over a wide range of ambient concentrations. Interactions among receptors, which are predominantly clustered at the cell poles, are crucial to this sensitivity. Although it has been suggested that the kinase CheA and the adapter protein CheW are integral for receptor connectivity, the exact coupling mechanism remains unclear. Here, we present a statistical-mechanics approach to model the receptor linkage mechanism itself, building on nanodisc and electron cryotomography experiments. Specifically, we investigate how the sensing behavior of mixed receptor clusters is affected by variations in the expression levels of CheA and CheW at a constant receptor density in the membrane. Our model compares favorably with dose-response curves from in vivo Förster resonance energy transfer (FRET measurements, demonstrating that the receptor-methylation level has only minor effects on receptor cooperativity. Importantly, our model provides an explanation for the non-intuitive conclusion that the receptor cooperativity decreases with increasing levels of CheA, a core signaling protein associated with the receptors, whereas the receptor cooperativity increases with increasing levels of CheW, a key adapter protein. Finally, we propose an evolutionary advantage as explanation for the recently suggested CheW-only linker structures.

  20. Characterization of astrocytic and neuronal benzodiazepine receptors

    Energy Technology Data Exchange (ETDEWEB)

    Bender, A.S.

    1988-01-01

    Primary cultures of astrocytes and neurons express benzodiazepine receptors. Neuronal benzodiazepine receptors were of high-affinity, K{sub D} values were 7.5-43 nM and the densities of receptors (B{sub max}) were 924-4131 fmol/mg protein. Astrocytes posses a high-affinity benzodiazepine receptor, K{sub D} values were 6.6-13 nM. The B{sub max} values were 6,033-12,000 fmol/mg protein. The pharmacological profile of the neuronal benzodiazepine receptor was that of the central-type benzodiazepine receptor, where clonazepam has a high-affinity and Ro 5-4864 (4{prime}-chlorodiazepam) has a low-affinity. Whereas astrocytic benzoidazepine receptor was characteristic of the so called peripheral-type benzodiazepine receptors, which shows a high-affinity towards Ro 5-4863, and a low-affinity towards clonazepam. The astrocytic benzodiazepine receptors was functionally correlated with voltage dependent calcium channels, since dihydropyridines and benzodiazepines interacted with ({sup 3}H) diazepam and ({sup 3}H) nitrendipine receptors with the same rank order of potency, showing a statistically significant correlation. No such correlation was observed in neurons.

  1. Assembly of PRR-containing receptors on scaffolds: a model for imidazoline I(1)-receptor action.

    Science.gov (United States)

    Musgrave, I F; Dehle, F C; Piletz, J

    2003-12-01

    IRAS, a putative clone of the I(1)-imidazoline receptor, possesses a proline-rich region (PRR) motif, which might interact with SH3 regions on tyrosine kinases, and an integrin-binding motif. Receptors with a PRR motif can generally assemble onto multi-element signaling complexes (eg., the beta(3)-receptor on the EGF receptor) and thereby modulate signal transduction. Integrins serve as scaffolds for multi-element signaling complexes, similar to that assembled with the EGF receptor. It is therefore possible that IRAS signals through a complex with other receptors.

  2. Subtype selective kainic acid receptor agonists

    DEFF Research Database (Denmark)

    Bunch, Lennart; Krogsgaard-Larsen, Povl

    2009-01-01

    (S)-Glutamic acid (Glu) is the major excitatory neurotransmitter in the mammalian central nervous system, activating the plethora of glutamate receptors (GluRs). In broad lines, the GluRs are divided into two major classes: the ionotropic Glu receptors (iGluRs) and the metabotropic Glu receptors (m......GluRs). Within the iGluRs, five subtypes (KA1, KA2, iGluR5-7) show high affinity and express full agonist activity upon binding of the naturally occurring amino acid kainic acid (KA). Thus these receptors have been named the KA receptors. This review describes all-to our knowledge-published KA receptor agonists...

  3. Mast Cell and Immune Inhibitory Receptors

    Institute of Scientific and Technical Information of China (English)

    LixinLi; ZhengbinYao

    2004-01-01

    Modulation by balancing activating and inhibitory receptors constitutes an important mechanism for regulating immune responses. Cells that are activated following ligation of receptors bearing immunoreceptor tyrosine-based activation motifs (ITAMs) can be negatively regulated by other receptors bearing immunoreceptor tyrosine-based inhibition motifs (ITIMs). Human mast cells (MCs) are the major effector cells of type I hypersensitivity and important participants in a number of disease processes. Antigen-mediated aggregation of IgE bound to its high-affinity receptor on MCs initiates a complex series of biochemical events leading to MC activation. With great detailed description and analysis of several inhibitory receptors on human MCs, a central paradigm of negative regulation of human MC activation by these receptors has emerged. Cellular & Molecular Immunology. 2004;1(6):408-415.

  4. The anatomy of mammalian sweet taste receptors.

    Science.gov (United States)

    Chéron, Jean-Baptiste; Golebiowski, Jérôme; Antonczak, Serge; Fiorucci, Sébastien

    2017-02-01

    All sweet-tasting compounds are detected by a single G-protein coupled receptor (GPCR), the heterodimer T1R2-T1R3, for which no experimental structure is available. The sweet taste receptor is a class C GPCR, and the recently published crystallographic structures of metabotropic glutamate receptor (mGluR) 1 and 5 provide a significant step forward for understanding structure-function relationships within this family. In this article, we recapitulate more than 600 single point site-directed mutations and available structural data to obtain a critical alignment of the sweet taste receptor sequences with respect to other class C GPCRs. Using this alignment, a homology 3D-model of the human sweet taste receptor is built and analyzed to dissect out the role of key residues involved in ligand binding and those responsible for receptor activation. Proteins 2017; 85:332-341. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  5. P2X receptors in epithelia

    DEFF Research Database (Denmark)

    Leipziger, Jens Georg

    2015-01-01

    pathways that inhibit epithelial absorption are currently not well understood. Epithelial P2X7 receptors show pronounced up-regulation during varies diseased states highlighting a role of purinergic signaling in epithelial pathophysiology. Importantly, functional effects of epithelial P2X receptors cover......P2X receptors are ubiquitously expressed in all epithelial tissues but their functional roles are less well studied. Here we review the current state of knowledge by focusing on functional effects of P2X receptor in secretory and in absorptive tissues. In glandular tissue like the parotid gland...... basolateral P2X receptors stimulate ion secretion via an increase of [Ca2+]i. In absorptive epithelia like the renal tubule P2X receptor stimulation mediates the inhibition of NaCl, Mg2+ and water transport in the thick ascending limb and the distal convoluted tubule, respectively. The underlying signaling...

  6. Nitrosamines as nicotinic receptor ligands.

    Science.gov (United States)

    Schuller, Hildegard M

    2007-05-30

    Nitrosamines are carcinogens formed in the mammalian organism from amine precursors contained in food, beverages, cosmetics and drugs. The potent carcinogen, NNK, and the weaker carcinogen, NNN, are nitrosamines formed from nicotine. Metabolites of the nitrosamines react with DNA to form adducts responsible for genotoxic effects. We have identified NNK as a high affinity agonist for the alpha7 nicotinic acetylcholine receptor (alpha7nAChR) whereas NNN bound with high affinity to epibatidine-sensitive nAChRs. Diethylnitrosamine (DEN) bound to both receptors but with lower affinity. High levels of the alpha7nAChR were expressed in human small cell lung cancer (SCLC) cell lines and in hamster pulmonary neuroendocrine cells (PNECs), which serve as a model for the cell of origin of human SCLC. Exposure of SCLC or PNECs to NNK or nicotine increased expression of the alpha7nAChR and caused influx of Ca(2+), activation of PKC, Raf-1, ERK1/2, and c-myc, resulting in the stimulation of cell proliferation. Signaling via the alpha7nAChR was enhanced when cells were maintained in an environment of 10-15% CO(2) similar to that in the diseased lung. Hamsters with hyperoxia-induced pulmonary fibrosis developed neuroendocrine lung carcinomas similar to human SCLC when treated with NNK, DEN, or nicotine. The development of the NNK-induced tumors was prevented by green tea or theophylline. The beta-adrenergic receptor agonist, isoproterenol or theophylline blocked NNK-induced cell proliferation in vitro. NNK and nicotine-induced hyperactivity of the alpha7nAChR/RAF/ERK1/2 pathway thus appears to play a crucial role in the development of SCLC in smokers and could be targeted for cancer prevention.

  7. Angiotensin II receptors in the gonads

    Energy Technology Data Exchange (ETDEWEB)

    Aguilera, G.; Millan, M.A.; Harwood, J.P.

    1989-05-01

    The presence of components of the renin-angiotensin system in ovaries and testes suggests that angiotensin II (AII) is involved in gonadal function, and thus we sought to characterize receptors for AII in rat and primate gonads. In the testes, autoradiographic studies showed receptors in the interstitium in all species. In rat interstitial cells fractionated by Percoll gradient, AII receptors coincided with hCG receptors indicating that AII receptors are located on the Leydig cells. In Leydig cells and membranes from rat and rhesus monkey prepuberal testes, AII receptors were specific for AII analogues and of high affinity (Kd=nM). During development, AII receptor content in rat testes decreases with age parallel to a fall in the ratio of interstitial to tubular tissue. In the ovary, the distribution of AII receptors was dependent on the stage of development, being high in the germinal epithelium and stromal tissue between five and 15 days, and becoming localized in secondary follicles in 20-and 40-day-old rats. No binding was found in primordial or primary follicles. In rhesus monkey ovary, AII receptors were higher in stromal tissue and lower in granulosa and luteal cells of the follicles. Characterization of the binding in rat and monkey ovarian membranes showed a single class of sites with a Kd in the nmol/L range and specificity similar to that of the adrenal glomerulosa and testicular AII receptors. Receptors for AII were also present in membrane fractions from PMSG/hCG primed rat ovaries. Infusion of AII (25 ng/min) or captopril (1.4 micrograms/min) during the PMSG/hCG induction period had no effect on ovarian weight or AII receptor concentration in the ovaries.

  8. Complex pharmacology of free fatty acid receptors

    OpenAIRE

    Milligan, Graeme; Shimpukade, Bharat; Ulven, Trond; Hudson, Brian D.

    2017-01-01

    G protein-coupled receptors (GPCRs) are historically the most successful family of drug targets. In recent times it has become clear that the pharmacology of these receptors is far more complex than previously imagined. Understanding of the pharmacological regulation of GPCRs now extends beyond simple competitive agonism or antagonism by ligands interacting with the orthosteric binding site of the receptor to incorporate concepts of allosteric agonism, allosteric modulation, signaling bias, c...

  9. Muscarinic Receptor Agonists and Antagonists

    Directory of Open Access Journals (Sweden)

    David R. Kelly

    2001-02-01

    Full Text Available A comprehensive review of pharmacological and medical aspects of the muscarinic class of acetylcholine agonists and antagonists is presented. The therapeutic benefits of achieving receptor subtype selectivity are outlined and applications in the treatment of Alzheimer’s disease are discussed. A selection of chemical routes are described, which illustrate contemporary methodology for the synthesis of chiral medicinal compounds (asymmetric synthesis, chiral pool, enzymes. Routes to bicyclic intrannular amines and intramolecular Diels-Alder reactions are highlighted.

  10. Emerging GLP-1 receptor agonists

    DEFF Research Database (Denmark)

    Lund, Asger; Knop, Filip K; Vilsbøll, Tina

    2011-01-01

    Introduction: Recently, glucagon-like peptide-1 receptor (GLP-1R) agonists have become available for the treatment of type 2 diabetes. These agents exploit the physiological effects of GLP-1, which is able to address several of the pathophysiological features of type 2 diabetes. GLP-1R agonists...... presently available are administered once or twice daily, but several once-weekly GLP-1R agonists are in late clinical development. Areas covered: The present review aims to give an overview of the clinical data on the currently available GLP-1R agonists used for treatment of type 2 diabetes, exenatide...

  11. New transmembrane AMPA receptor regulatory protein isoform, gamma-7, differentially regulates AMPA receptors

    National Research Council Canada - National Science Library

    Kato, Akihiko S; Zhou, Wei; Milstein, Aaron D; Knierman, Mike D; Siuda, Edward R; Dotzlaf, Joe E; Yu, Hong; Hale, John E; Nisenbaum, Eric S; Nicoll, Roger A; Bredt, David S

    2007-01-01

    AMPA-type glutamate receptors (GluRs) mediate most excitatory signaling in the brain and are composed of GluR principal subunits and transmembrane AMPA receptor regulatory protein (TARP) auxiliary subunits...

  12. The angiotensin Ⅱ type 1 receptor and receptor-associated proteins

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The mechanisms of regulation, activation and signal transduction of the angiotensin Ⅱ(Ang Ⅱ) type 1 (AT1) receptor have been studied extensively in the decade after its cloning. The AT1receptor is a major component of the renin-angiotensin system (RAS). It mediates the classical biological actions of Ang Ⅱ. Among the structures required for regulation and activation of the receptor, its carboxylterminal region plays crucial roles in receptor internalization, desensitization and phosphorylation. The mechanisms involved in heterotrimeric G-protein coupling to the receptor, activation of the downstreamsignaling pathway by G proteins and the Ang Ⅱ signal transduction pathways leading to specific cellularresponses are discussed. In addition, recent work on the identification and characterization of novel proteinsassociated with carboxyl-terminus of the AT1 receptor is presented. These novel proteins will advance ourunderstanding of how the receptor is internalized and recycled as they provide molecular mechanisms for the activation and regulation of G-protein-coupled receptors.

  13. Mechanisms of NMDA Receptor- and Voltage-Gated L-Type Calcium Channel-Dependent Hippocampal LTP Critically Rely on Proteolysis That Is Mediated by Distinct Metalloproteinases.

    Science.gov (United States)

    Wiera, Grzegorz; Nowak, Daria; van Hove, Inge; Dziegiel, Piotr; Moons, Lieve; Mozrzymas, Jerzy W

    2017-02-01

    Long-term potentiation (LTP) is widely perceived as a memory substrate and in the hippocampal CA3-CA1 pathway, distinct forms of LTP depend on NMDA receptors (nmdaLTP) or L-type voltage-gated calcium channels (vdccLTP). LTP is also known to be effectively regulated by extracellular proteolysis that is mediated by various enzymes. Herein, we investigated whether in mice hippocampal slices these distinct forms of LTP are specifically regulated by different metalloproteinases (MMPs). We found that MMP-3 inhibition or knock-out impaired late-phase LTP in the CA3-CA1 pathway. Interestingly, late-phase LTP was also decreased by MMP-9 blockade. When both MMP-3 and MMP-9 were inhibited, both early- and late-phase LTP was impaired. Using immunoblotting, in situ zymography, and immunofluorescence, we found that LTP induction was associated with an increase in MMP-3 expression and activity in CA1 stratum radiatum. MMP-3 inhibition and knock-out prevented the induction of vdccLTP, with no effect on nmdaLTP. L-type channel-dependent LTP is known to be impaired by hyaluronic acid digestion. We found that slice treatment with hyaluronidase occluded the effect of MMP-3 blockade on LTP, further confirming a critical role for MMP-3 in this form of LTP. In contrast to the CA3-CA1 pathway, LTP in the mossy fiber-CA3 projection did not depend on MMP-3, indicating the pathway specificity of the actions of MMPs. Overall, our study indicates that the activation of perisynaptic MMP-3 supports L-type channel-dependent LTP in the CA1 region, whereas nmdaLTP depends solely on MMP-9. Various types of long-term potentiation (LTP) are correlated with distinct phases of memory formation and retrieval, but the underlying molecular signaling pathways remain poorly understood. Extracellular proteases have emerged as key players in neuroplasticity phenomena. The present study found that L-type calcium channel-dependent LTP in the CA3-CA1 hippocampal projection is critically regulated by the activity

  14. ABA Receptors: Past, Present and Future

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Jianjun [Harvard University; Yang, Xiaohan [ORNL; Weston, David [ORNL; Chen, Jay [ORNL

    2011-01-01

    Abscisic acid (ABA) is the key plant stress hormone. Consistent with the earlier studies in support of the presence of both membrane- and cytoplasm-localized ABA receptors, recent studies have identified multiple ABA receptors located in various subcellular locations. These include a chloroplast envelope-localized receptor (the H subunit of Chloroplast Mg2+-chelatase/ABA Receptor), two plasma membrane-localized receptors (G-protein Coupled Receptor 2 and GPCR-type G proteins), and one cytosol/nucleus-localized Pyrabactin Resistant (PYR)/PYR-Like (PYL)/Regulatory Component of ABA Receptor 1 (RCAR). Although the downstream molecular events for most of the identified ABA receptors are currently unknown, one of them, PYR/PYL/RACR was found to directly bind and regulate the activity of a long-known central regulator of ABA signaling, the A-group protein phosphatase 2C (PP2C). Together with the Sucrose Non-fermentation Kinase Subfamily 2 (SnRK2s) protein kinases, a central signaling complex (ABA-PYR-PP2Cs-SnRK2s) that is responsible for ABA signal perception and transduction is supported by abundant genetic, physiological, biochemical and structural evidence. The identification of multiple ABA receptors has advanced our understanding of ABA signal perception and transduction while adding an extra layer of complexity.

  15. Challenges in imaging cell surface receptor clusters

    Science.gov (United States)

    Medda, Rebecca; Giske, Arnold; Cavalcanti-Adam, Elisabetta Ada

    2016-01-01

    Super-resolution microscopy offers unique tools for visualizing and resolving cellular structures at the molecular level. STED microscopy is a purely optical method where neither complex sample preparation nor mathematical post-processing is required. Here we present the use of STED microscopy for imaging receptor cluster composition. We use two-color STED to further determine the distribution of two different receptor subunits of the family of receptor serine/threonine kinases in the presence or absence of their ligands. The implications of receptor clustering on the downstream signaling are discussed, and future challenges are also presented.

  16. Neuropeptide Receptor Transcriptome Reveals Unidentified Neuroendocrine Pathways

    Science.gov (United States)

    Yamanaka, Naoki; Yamamoto, Sachie; Žitňan, Dušan; Watanabe, Ken; Kawada, Tsuyoshi; Satake, Honoo; Kaneko, Yu; Hiruma, Kiyoshi; Tanaka, Yoshiaki; Shinoda, Tetsuro; Kataoka, Hiroshi

    2008-01-01

    Neuropeptides are an important class of molecules involved in diverse aspects of metazoan development and homeostasis. Insects are ideal model systems to investigate neuropeptide functions, and the major focus of insect neuropeptide research in the last decade has been on the identification of their receptors. Despite these vigorous efforts, receptors for some key neuropeptides in insect development such as prothoracicotropic hormone, eclosion hormone and allatotropin (AT), remain undefined. In this paper, we report the comprehensive cloning of neuropeptide G protein-coupled receptors from the silkworm, Bombyx mori, and systematic analyses of their expression. Based on the expression patterns of orphan receptors, we identified the long-sought receptor for AT, which is thought to stimulate juvenile hormone biosynthesis in the corpora allata (CA). Surprisingly, however, the AT receptor was not highly expressed in the CA, but instead was predominantly transcribed in the corpora cardiaca (CC), an organ adjacent to the CA. Indeed, by using a reverse-physiological approach, we purified and characterized novel allatoregulatory peptides produced in AT receptor-expressing CC cells, which may indirectly mediate AT activity on the CA. All of the above findings confirm the effectiveness of a systematic analysis of the receptor transcriptome, not only in characterizing orphan receptors, but also in identifying novel players and hidden mechanisms in important biological processes. This work illustrates how using a combinatorial approach employing bioinformatic, molecular, biochemical and physiological methods can help solve recalcitrant problems in neuropeptide research. PMID:18725956

  17. Neuropeptide receptor transcriptome reveals unidentified neuroendocrine pathways.

    Directory of Open Access Journals (Sweden)

    Naoki Yamanaka

    Full Text Available Neuropeptides are an important class of molecules involved in diverse aspects of metazoan development and homeostasis. Insects are ideal model systems to investigate neuropeptide functions, and the major focus of insect neuropeptide research in the last decade has been on the identification of their receptors. Despite these vigorous efforts, receptors for some key neuropeptides in insect development such as prothoracicotropic hormone, eclosion hormone and allatotropin (AT, remain undefined. In this paper, we report the comprehensive cloning of neuropeptide G protein-coupled receptors from the silkworm, Bombyx mori, and systematic analyses of their expression. Based on the expression patterns of orphan receptors, we identified the long-sought receptor for AT, which is thought to stimulate juvenile hormone biosynthesis in the corpora allata (CA. Surprisingly, however, the AT receptor was not highly expressed in the CA, but instead was predominantly transcribed in the corpora cardiaca (CC, an organ adjacent to the CA. Indeed, by using a reverse-physiological approach, we purified and characterized novel allatoregulatory peptides produced in AT receptor-expressing CC cells, which may indirectly mediate AT activity on the CA. All of the above findings confirm the effectiveness of a systematic analysis of the receptor transcriptome, not only in characterizing orphan receptors, but also in identifying novel players and hidden mechanisms in important biological processes. This work illustrates how using a combinatorial approach employing bioinformatic, molecular, biochemical and physiological methods can help solve recalcitrant problems in neuropeptide research.

  18. Abscisic Acid Receptors: Past, Present and Future

    Institute of Scientific and Technical Information of China (English)

    Jianjun Guo; Xiaohan Yang; David J. Weston; Jin-Gui Chen

    2011-01-01

    Abscisic acid (ABA) is the key plant stress hormone. Consistent with the earlier studies in support of the presence of both membrane- and cytoplasm-localized ABA receptors, recent studies have identified multiple ABA receptors located in various subcellular locations. These include a chloroplast envelope-localized receptor (the H subunit of Chloroplast Mg2+-chelatase/ABA Receptor), two plasma membrane-localized receptors (G-protein Coupled Receptor 2 and GPCR-type G proteins),and one cytosol/nucleus-localized Pyrabactin Resistant (PYR)/PYR-Like (PYL)/Regulatory Component of ABA Receptor 1 (RCAR). Although the downstream molecular events for most of the identified ABA receptors are currently unknown, one of them, PYR/PYL/RCAR was found to directly bind and regulate the activity of a long-known central regulator of ABA signaling, the A-group protein phosphatase 2C (PP2C). Together with the Sucrose Non-fermentation Kinase Subfamily 2 (SnRK2s) protein kinases, a central signaling complex (ABA-PYR-PP2Cs-SnRK2s) that is responsible for ABA signal perception and transduction is supported by abundant genetic, physiological, biochemical and structural evidence. The identification of multiple ABA receptors has advanced our understanding of ABA signal perception and transduction while adding an extra layer of complexity.

  19. CERAPP: Collaborative Estrogen Receptor Activity Prediction Project

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data from a large-scale modeling project called CERAPP (Collaborative Estrogen Receptor Activity Prediction Project) demonstrating using predictive computational...

  20. Identification and mechanism of ABA receptor antagonism

    KAUST Repository

    Melcher, Karsten

    2010-08-22

    The phytohormone abscisic acid (ABA) functions through a family of fourteen PYR/PYL receptors, which were identified by resistance to pyrabactin, a synthetic inhibitor of seed germination. ABA activates these receptors to inhibit type 2C protein phosphatases, such as ABI1, yet it remains unclear whether these receptors can be antagonized. Here we demonstrate that pyrabactin is an agonist of PYR1 and PYL1 but is unexpectedly an antagonist of PYL2. Crystal structures of the PYL2-pyrabactin and PYL1-pyrabactin-ABI1 complexes reveal the mechanism responsible for receptor-selective activation and inhibition, which enables us to design mutations that convert PYL1 to a pyrabactin-inhibited receptor and PYL2 to a pyrabactin-activated receptor and to identify new pyrabactin-based ABA receptor agonists. Together, our results establish a new concept of ABA receptor antagonism, illustrate its underlying mechanisms and provide a rational framework for discovering novel ABA receptor ligands. © 2010 Nature America, Inc. All rights reserved.

  1. Regulation of Estrogen Receptor Nuclear Export by Ligand-Induced and p38-Mediated Receptor Phosphorylation

    OpenAIRE

    Lee, Heehyoung; Bai, Wenlong

    2002-01-01

    Estrogen receptors are phosphoproteins which can be activated by ligands, kinase activators, or phosphatase inhibitors. Our previous study showed that p38 mitogen-activated protein kinase was involved in estrogen receptor activation by estrogens and MEKK1. Here, we report estrogen receptor-dependent p38 activation by estrogens in endometrial adenocarcinoma cells and in vitro and in vivo phosphorylation of the estrogen receptor α mediated through p38. The phosphorylation site was identified as...

  2. Studies on mu and delta opioid receptor selectivity utilizing chimeric and site-mutagenized receptors.

    Science.gov (United States)

    Wang, W W; Shahrestanifar, M; Jin, J; Howells, R D

    1995-01-01

    Opioid receptors are members of the guanine nucleotide binding protein (G protein)-coupled receptor family. Three types of opioid receptors have been cloned and characterized and are referred to as the delta, kappa and mu types. Analysis of receptor chimeras and site-directed mutant receptors has provided a great deal of information about functionally important amino acid side chains that constitute the ligand-binding domains and G-protein-coupling domains of G-protein-coupled receptors. We have constructed delta/mu opioid receptor chimeras that were express in human embryonic kidney 293 cells in order to define receptor domains that are responsible for receptor type selectivity. All chimeric receptors and wild-type delta and mu opioid receptors displayed high-affinity binding of etorphine (an agonist), naloxone (an antagonist), and bremazocine (a mixed agonist/antagonist). In contrast, chimeras that lacked the putative first extracellular loop of the mu receptor did not bind the mu-selective peptide [D-Ala2,MePhe4,Gly5-ol]enkephalin (DAMGO). Chimeras that lacked the putative third extracellular loop of the delta receptor did not bind the delta-selective peptide, [D-Ser2,D-Leu5]enkephalin-Thr (DSLET). Point mutations in the putative third extracellular loop of the wild-type delta receptor that converted vicinal arginine residues to glutamine abolished DSLET binding while not affecting bremazocine, etorphine, and naltrindole binding. We conclude that amino acids in the putative first extracellular loop of the mu receptor are critical for high-affinity DAMGO binding and that arginine residues in the putative third extracellular loop of the delta receptor are important for high-affinity DSLET binding. Images Fig. 3 PMID:8618916

  3. Epac2: a sulfonylurea receptor?

    Science.gov (United States)

    Rehmann, Holger

    2012-02-01

    Sulfonylureas are widely used oral drugs in the treatment of diabetes mellitus. They function by the inhibition of ATP-sensitive K+ channels in pancreatic β-cells, which are thus considered the 'classical' sulfonylurea receptor. Next to the ATP-sensitive K+ channels, additional sulfonylurea-interacting proteins were identified, which might contribute to the physiological effects of this drug family. Most recently, Epac2 (exchange protein directly activated by cAMP 2) was added to the list of sulfonylurea receptors. However, this finding caused controversy in the literature. The critical discussion of the present paper comes to the conclusion that sulfonylureas are not able to activate Epac2 directly and are unlikely to bind to Epac2. Increased blood glucose levels after food intake result in the secretion of insulin from pancreatic β-cells. Glucose levels are detected 'indirectly' by β-cells: owing to increased glycolysis rates, the ratio of cellular ATP/ADP increases and causes the closure of ATP-sensitive K+ channels. In consequence, cells depolarize and voltage-dependent Ca2+ channels open to cause an increase in the cellular Ca2+ concentration. Finally, Ca2+ induces the fusion of insulin-containing granules with the plasma membrane. Sulfonylureas, such as tolbutamide, glibenclamide or acetohexamide, form a class of orally applicable drugs used in the treatment of non-insulin-dependent diabetes mellitus.

  4. Prorenin receptor in kidney development.

    Science.gov (United States)

    Yosypiv, Ihor V

    2017-03-01

    Prorenin receptor (PRR), a receptor for renin and prorenin and an accessory subunit of the vacuolar proton pump H(+)-ATPase, is expressed in the developing kidney. Global loss of PRR is lethal in mice, and PRR mutations are associated with a high blood pressure, left ventricular hypertrophy and X-linked mental retardation in humans. With the advent of modern gene targeting techniques, including conditional knockout approaches, several recent studies have demonstrated critical roles for the PRR in several lineages of the developing kidney. PRR signaling has been shown to be essential for branching morphogenesis of the ureteric bud (UB), nephron progenitor survival and nephrogenesis. PRR regulates these developmental events through interactions with other transcription and growth factors. Several targeted PRR knockout animal models have structural defects mimicking congenital anomalies of the kidney and urinary tract observed in humans. The aim of this review, is to highlight new insights into the cellular and molecular mechanisms by which PRR may regulate UB branching, terminal differentiation and function of UB-derived collecting ducts, nephron progenitor maintenance, progression of nephrogenesis and normal structural kidney development and function.

  5. Excitatory amino acid receptor antagonists

    DEFF Research Database (Denmark)

    Johansen, T N; Frydenvang, Karla Andrea; Ebert, B

    1997-01-01

    We have previously shown that (RS)-2-amino-2-(5-tert-butyl-3-hydroxyisoxazol-4-yl)acetic acid (ATAA) is an antagonist at N-methyl-D-aspartic acid (NMDA) and (RS)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) receptors. We have now resolved ATAA via diastereomeric salt formation......)-phenylethylamine salt of N-BOC-(R)-ATAA. Like ATAA, neither (R)- nor (S)-ATAA significantly affected (IC50 > 100 microM) the receptor binding of tritiated AMPA, kainic acid, or (RS)-3-(2-carboxypiperazin-4-yl)propyl-1-phosphonic acid, the latter being a competitive NMDA antagonist. Electrophysiological experiments......, using the rat cortical wedge preparation, showed the NMDA antagonist effect as well as the AMPA antagonist effect of ATAA to reside exclusively in the (R)-enantiomer (Ki = 75 +/- 5 microM and 57 +/- 1 microM, respectively). Neither (R)- nor (S)-ATAA significantly reduced kainic acid-induced excitation...

  6. Androgen receptor drives cellular senescence.

    Directory of Open Access Journals (Sweden)

    Yelena Mirochnik

    Full Text Available The accepted androgen receptor (AR role is to promote proliferation and survival of prostate epithelium and thus prostate cancer progression. While growth-inhibitory, tumor-suppressive AR effects have also been documented, the underlying mechanisms are poorly understood. Here, we for the first time link AR anti-cancer action with cell senescence in vitro and in vivo. First, AR-driven senescence was p53-independent. Instead, AR induced p21, which subsequently reduced ΔN isoform of p63. Second, AR activation increased reactive oxygen species (ROS and thereby suppressed Rb phosphorylation. Both pathways were critical for senescence as was proven by p21 and Rb knock-down and by quenching ROS with N-Acetyl cysteine and p63 silencing also mimicked AR-induced senescence. The two pathways engaged in a cross-talk, likely via PML tumor suppressor, whose localization to senescence-associated chromatin foci was increased by AR activation. All these pathways contributed to growth arrest, which resolved in senescence due to concomitant lack of p53 and high mTOR activity. This is the first demonstration of senescence response caused by a nuclear hormone receptor.

  7. Receptor oligomerization in family B1 of G-protein-coupled receptors

    DEFF Research Database (Denmark)

    Roed, Sarah Norklit; Ørgaard, Anne; Jørgensen, Rasmus

    2012-01-01

    , the glucagon receptor, and the receptors for parathyroid hormone (PTHR1 and PTHR2). The dysregulation of several family B1 receptors is involved in diseases, such as diabetes, chronic inflammation, and osteoporosis which underlines the pathophysiological importance of this GPCR subfamily. In spite of this...

  8. The G protein-coupled receptor, class C, group 6, subtype A (GPRC6A) receptor

    DEFF Research Database (Denmark)

    Clemmensen, C; Smajilovic, S; Wellendorph, P;

    2014-01-01

    GPRC6A (G protein-coupled receptor, class C, group 6, subtype A) is a class C G protein-coupled receptor, that has been cloned from human, mouse and rat. Several groups have shown that the receptor is activated by a range of basic and small aliphatic L-α-amino acids of which L-arginine, L...

  9. The role of the CGRP-receptor component protein (RCP) in adrenomedullin receptor signal transduction.

    Science.gov (United States)

    Prado, M A; Evans-Bain, B; Oliver, K R; Dickerson, I M

    2001-11-01

    G protein-coupled receptors are usually thought to act as monomer receptors that bind ligand and then interact with G proteins to initiate signal transduction. In this study we report an intracellular peripheral membrane protein named the calcitonin gene-related peptide (CGRP)-receptor component protein (RCP) required for signal transduction at the G protein-coupled receptor for adrenomedullin. Cell lines were made that expressed an antisense construct of the RCP cDNA, and in these cells diminished RCP expression correlated with loss of adrenomedullin signal transduction. In contrast, loss of RCP did not diminish receptor density or affinity, therefore RCP does not appear to act as a chaperone protein. Instead, RCP represents a novel class of protein required to couple the adrenomedullin receptor to the cellular signal transduction pathway. A candidate adrenomedullin receptor named the calcitonin receptor-like receptor (CRLR) has been described, which forms high affinity adrenomedullin receptors when co-expressed with the accessory protein receptor-activity modifying protein 2 (RAMP2). RCP co-immunoprecipitated with CRLR and RAMP2, indicating that a functional adrenomedullin receptor is composed of at least three proteins: the ligand binding protein (CRLR), an accessory protein (RAMP2), and a coupling protein for signal transduction (RCP).

  10. A novel fluorescent receptor assay : Based upon receptors embedded in labeled liposomes

    NARCIS (Netherlands)

    Viel, Gerhard Theodoor

    1999-01-01

    Receptor proteins play an essential role in life. All organisms, from bacteria to plants, animals and human beings use receptors for their response to (external) signals. By definition, a receptor is a (macro) molecule which is able to recognize a distinct chemical entity (e.g. a hormone or neurotra

  11. A novel fluorescent receptor assay : based upon receptors embedded in labeled liposomes

    NARCIS (Netherlands)

    Viel, Gerhard Theodoor

    1999-01-01

    Receptor proteins play an essential role in life. All organisms, from bacteria to plants, animals and human beings use receptors for their response to (external) signals. By definition, a receptor is a (macro) molecule which is able to recognize a distinct chemical entity (e.g. a hormone or neurotra

  12. Microarray-based determination of estrogen receptor, progesterone receptor, and HER2 receptor status in breast cancer

    NARCIS (Netherlands)

    P. Roepman; H.M. Horlings; O. Krijgsman; M. Kok; J.M. Bueno-de-Mesquita; R. Bender; S.C. Linn; A.M. Glas; M.J. van de Vijver

    2009-01-01

    Purpose: The level of estrogen receptor (ER), progesterone receptor (PR), and HER2 aids in the determination of prognosis and treatment of breast cancer. Immunohistochemistry is currently the predominant method for assessment, but differences in methods and interpretation can substantially affect th

  13. Novel CD44 receptor targeting multifunctional “nano-eggs” based on double pH-sensitive nanoparticles for co-delivery of curcumin and paclitaxel to cancer cells and cancer stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Daquan, E-mail: cdq1981@126.com [Peking University, School of Pharmaceutical Sciences, Health Science Center (China); Wang, Guohua [China Academy of Chinese Medical Sciences, Institute of Chinese Materia Madica (China); Song, Weiguo [Shouguang Fukang Pharmceutial Co., Ltd. (China); Zhang, Qiang, E-mail: zqdodo@bjmu.edu.cn [Peking University, School of Pharmaceutical Sciences, Health Science Center (China)

    2015-10-15

    Most anticancer drugs cannot kill cancer stem cells (CSCs) effectively, which lead to the failure of anticancer chemotherapy, such as relapse and metastasis. In this study, we prepared a multifunctional oligosaccharides of hyaluronan (oHA) conjugates, oHA-histidine-menthone 1,2-glycerol ketal (oHM). The oHM conjugates possess pH-sensitive menthone 1,2-glycerol ketal (MGK) as hydrophobic moieties and oHA as the target of CD44 receptor. Anticancer drugs, curcumin(Cur) and paclitaxel(PTX), were loaded into oHM micelles via self-assembly. Then, oHM micelles were mineralized through controlled deposition of inorganic calcium and phosphate ions on the nanoparticular shell via a sequential addition method to fabricate the “nano-eggs.” The formed nano-eggs had a smaller size (120.6 ± 4.5 nm) than oHM micelles (158.6 ± 6.4 nm), indicating that mineralization made the appearance of compact nanoparticles. Interestingly, when the nano-eggs were put into the acidic conditions (pH 6.5), their outer shell(inorganic minerals) will be destroyed with the larger size, while the “nano-eggs” were stable under pH 7.4. For both nano-eggs and oHM micelles, the Cur and PTX were released in a sustained manner depending on the pH of the solution. However, the nano-eggs showed much lower released than the oHM micelles due to the dissolution of the inorganic minerals and pH-sensitive ketal at mildly acidic environments (pH 6.5). In vivo study, the nano-eggs could get to the tumor site more effectively than oHM micelles. CSCs were sorted by a side population assay from MDA-MB-231 breast cancer cell lines over-expressing CD44 receptors. Antitumor activity was also evaluated on MDA-MB-231 xenografts in nude mice. The antitumor efficacy indicated that nano-eggs with co-delivery of Cur and PTX produced the strongest antitumor efficacy, and nano-eggs showed strong activity against cancer stem cells. These double pH-sensitive nano-eggs may provide a promising strategy for drug

  14. Group I Metabotropic Glutamate Receptor Interacting Proteins: Fine-Tuning Receptor Functions in Health and Disease.

    Science.gov (United States)

    Kalinowska, Magdalena; Francesconi, Anna

    2016-01-01

    Group I metabotropic glutamate receptors mediate slow excitatory neurotransmission in the central nervous system and are critical to activity-dependent synaptic plasticity, a cellular substrate of learning and memory. Dysregulated receptor signaling is implicated in neuropsychiatric conditions ranging from neurodevelopmental to neurodegenerative disorders. Importantly, group I metabotropic glutamate receptor signaling functions can be modulated by interacting proteins that mediate receptor trafficking, expression and coupling efficiency to signaling effectors. These interactions afford cell- or pathway-specific modulation to fine-tune receptor function, thus representing a potential target for pharmacological interventions in pathological conditions.

  15. Identifying the receptor subtype selectivity of retinoid X and retinoic acid receptors via quantum mechanics.

    Science.gov (United States)

    Tsuji, Motonori; Shudo, Koichi; Kagechika, Hiroyuki

    2017-03-01

    Understanding and identifying the receptor subtype selectivity of a ligand is an important issue in the field of drug discovery. Using a combination of classical molecular mechanics and quantum mechanical calculations, this report assesses the receptor subtype selectivity for the human retinoid X receptor (hRXR) and retinoic acid receptor (hRAR) ligand-binding domains (LBDs) complexed with retinoid ligands. The calculated energies show good correlation with the experimentally reported binding affinities. The technique proposed here is a promising method as it reveals the origin of the receptor subtype selectivity of selective ligands.

  16. Down regulation of epidermal growth factor receptors: direct demonstration of receptor degradation in human fibroblasts

    OpenAIRE

    1984-01-01

    The metabolism of the receptor for epidermal growth factor (EGF) has been measured by labeling the receptor in vivo with radioactive amino acid precursors and then determining, by immunoprecipitation with specific anti-EGF receptor antisera, the rate of degradation of the receptor when the cells are placed in a nonradioactive medium. In human fibroblasts the rate of EGF receptor degradation (t1/2 = 10.1 h) was faster than the rate of degradation of total cell protein. When EGF was added to th...

  17. Transitional cell carcinoma express vitamin D receptors

    DEFF Research Database (Denmark)

    Hermann, G G; Andersen, C B

    1997-01-01

    .05). Similarly, also tumor grade appeared to be related to the number of cells expressing the receptor. Normal urothlium also expressed VDR but only with low intensity. Our study shows that TCC cells possess the VDR receptor which may make them capable to respond to stimulation with vitamin D, but functional...

  18. METHODOLOGICAL ASPECTS OF QUANTITATIVE RECEPTOR ASSAYS

    NARCIS (Netherlands)

    SMISTEROVA, J; ENSING, K; DEZEEUW, RA

    1994-01-01

    Receptor assays occupy a particular position in the methods used in bioanalysis, as they do not exploit the physico-chemical properties of the analyte. These assays make use of the property of the analyte to bind to the specific binding site (receptor) and to competitively replace a labelled ligand

  19. Transient receptor potential channels in essential hypertension

    DEFF Research Database (Denmark)

    Liu, Daoyan; Scholze, Alexandra; Zhu, Zhiming

    2006-01-01

    The role of nonselective cation channels of the transient receptor potential channel (TRPC) family in essential hypertension has not yet been investigated.......The role of nonselective cation channels of the transient receptor potential channel (TRPC) family in essential hypertension has not yet been investigated....

  20. [Olfactory esthesioneuroblastoma: scintigraphic expression of somatostatin receptors].

    Science.gov (United States)

    García Vicente, A; García Del Castillo, E; Soriano Castrejón, A; Alonso Farto, J

    1999-10-01

    Esthesioneuroblastoma is an uncommon tumor originating in the upper nasal cavity and constitutes 3% of all intranasal neoplasms. Few references exist about the expression of somatostatin receptors in these tumors. Our case demonstrates a good correlation between the somatostatin receptor scintigraphy and magnetic resonance imaging.