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1.
Arq. bras. oftalmol ; 80(2): 74-77, Mar.-Apr. 2017. tab
Article in English | LILACS | ID: biblio-838797

ABSTRACT

ABSTRACT Purpose: To investigate the effect of nicotinamide on the secretion of pro-an giogenic and pro-inflammatory cytokines in uveal melanoma cell lines. Methods: Two human uveal melanoma cell lines (92.1 and OCM-1) were treated with nicotinamide (10 mmol/L) or control media for 48 hours in culture. The su perna tant from each culture was used in sandwich enzyme-linked immuno sorbent assay-based angiogenesis and inflammation arrays to evaluate the effects of exogenously administered nicotinamide on the secretion of a total of 20 pro-an gio genic and pro-inflammatory proteins. Results: Seven pro-angiogenic cytokines were detected under control conditions for both uveal melanoma cell lines. Treatment with nicotinamide resulted in a significant decrease in secretion of the following pro-angiogenic cytokines: angiogenin, angiopoietin-2, epidermal growth factor, and vascular epithelial growth factor-A in the 92.1 cells; basic fibroblast growth factor in the OCM-1 cells; and placenta growth factor in both cell lines. Among the pro-inflammatory proteins, monocyte chemotactic protein-1 and interleukin-8 were expressed in both untreated cell lines and both were significantly reduced when treated with nicotinamide. Conclusions: Results from this in vitro model suggest that nicotinamide may have anti-inflammatory and anti-angiogenic properties, which may open the possibility of using it as a chemopreventive agent for uveal melanoma; however, further studies including animal models are warranted.


RESUMO Objetivo: Acredita-se que a nicotinamida (NIC) seja capaz de diminuir a angiogênese induzida pelo fator de crescimento endotelial vascular (VEGF). Investigar os efeitos da nicotinamida sobre a secreção de citocinas pró-angiogênicas e pró-inflamatórias em linhagens de células de melanoma uveal humano (UM). Métodos: Duas linhagens de células humanas de UM (92,1 e OCM-1) foram tratadas com NIC (10 mmol/L) ou apenas com meio de cultura por 48 horas. O sobrenadante das culturas obtido após a administração de nicotinamida foi comparado com o sobrenadante das culturas controle quanto à expressão de 20 fatores pró-angiogênicos e pró-inflamatórios, pela técnica de enzyme-linked immunosorbent assay (ELISA). Resultados: Sete citocinas pró-angiogênicas foram detectadas nas condições de controle em ambas as linhagens de células de UM. O tratamento com nicotinamida promoveu uma redução significativa da secreção das seguintes citocinas angiogênicas: Angiogenina, ANG2, EGF e VEGF-A em células 92.1; bFGF em células OCM-1; PIGF em ambas as linhagens celulares. Quanto às proteínas pró-inflamatórias, a expressão de MCP-1 e IL-8 foi significativamente reduzida com a administração de nicotinamida em relação às culturas de células que não receberam o tratamento. Conclusões: Nicotinamida apresenta propriedades anti-inflamatórias e anti-angiogênicas em modelo experimental in vitro. Tais efeitos sugerem a possibilidade de utilizar esta substância na quimioprevenção do UM. Entretanto, estudos com modelos experimentais in vivo são necessários para melhor avaliar o benefício do tratamento do UM com nicotinamida.


Subject(s)
Humans , Uveal Neoplasms/metabolism , Cytokines/drug effects , Niacinamide/pharmacology , Angiogenesis Inhibitors/pharmacology , Melanoma/metabolism , Anti-Inflammatory Agents/pharmacology , Ribonuclease, Pancreatic/drug effects , Uveal Neoplasms/blood supply , Cytokines/metabolism , Fibroblast Growth Factor 2/drug effects , Interleukin-8/drug effects , Chemokine CCL2/drug effects , Cell Line, Tumor , Angiopoietin-2/metabolism , Epidermal Growth Factor/drug effects , Placenta Growth Factor/drug effects , Melanoma/blood supply
2.
Korean Journal of Ophthalmology ; : 163-171, 2016.
Article in English | WPRIM | ID: wpr-50646

ABSTRACT

PURPOSE: To investigate the properties of angiogenin (ANG) as a potential tool for the diagnosis and grading of dry eye syndrome (DES) by analyzing tear protein profiles. METHODS: Tear samples were collected with capillary tubes from 52 DES patients and 29 normal individuals as controls. Tear protein profiles were analyzed with an immunodot blot assay as a screening test. To confirm that the tear ANG levels were in inverse proportion to the disease severity grade, the ANG and lactoferrin (LF) tear contents of normal controls and DES patients were compared in an enzyme-linked immunosorbent assay. RESULTS: In the immunodot blot assay, the ANG area was lower in patients with grades 3 and 4 DES than in normal controls. The areas of basic fibroblast growth factor, transforming growth factor β2, and interleukin 10 were significantly greater than those of normal controls only in grade 4 DES patients, but these proteins were not linearly correlated with dry eye severity. Upon enzyme-linked immunosorbent assay analysis, the mean concentrations of ANG and LF decreased significantly as dry eye severity increased, except between grades 1 and 2. In addition, the ratios of ANG and LF to total tear proteins were correlated significantly with DES severity. CONCLUSIONS: ANG level was significantly lower in DES patients than in normal controls, and was significantly correlated with the worsening severity of DES, except between grades 1 and 2, as was LF. Therefore, ANG may be a useful measure of DES severity through proteomic analysis.


Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Angiogenesis Inducing Agents/pharmacology , Dry Eye Syndromes/diagnosis , Enzyme-Linked Immunosorbent Assay , Follow-Up Studies , Immunoblotting , Proteomics/methods , Ribonuclease, Pancreatic/pharmacology , Severity of Illness Index , Tears/chemistry
3.
Journal of Huazhong University of Science and Technology (Medical Sciences) ; (6): 82-87, 2016.
Article in English | WPRIM | ID: wpr-285307

ABSTRACT

Neamine, a non-toxic derivative of neomycin, has recently been shown to have antitumor activities in various types of cancers. However, its effect on pancreatic cancer is still unknown. The study aimed to investigate its antitumor activity on pancreatic cancer and the underlying mechanisms. MTT assay was used to observe the effect of neamine on angiogenin (ANG)-induced AsPC-1 cell proliferation. Tissue microassay and immunofluorescence staining were used to detect the expression of ANG and its nuclear translocation, respectively. Tumor xenografts were established by subcutaneous inoculation of AsPC-1 pancreatic cancer cells into the right flanks of nude mice, and neamine was injected subcutaneously. Immunohistochemistry was done to observe the expression of ANG, CD31 and Ki-67 in tumor xenografts. It was found that neamine blocked the nuclear translocation of ANG effectively and inhibited ANG-induced AsPC-1 cell proliferation in a dose-dependent manner. Neamine had anti-tumor effects on AsPC-1 xenograft models. Consistently, neamine reduced the expression levels of ANG, Ki-67 and CD31 in tumor xenografts. It was concluded that neamine may be a promising agent for treatment of pancreatic cancer.


Subject(s)
Adult , Animals , Humans , Male , Mice , Middle Aged , Antibiotics, Antineoplastic , Pharmacology , Therapeutic Uses , Carcinoma , Drug Therapy , Cell Line, Tumor , Cell Proliferation , Framycetin , Pharmacology , Therapeutic Uses , Ki-67 Antigen , Genetics , Metabolism , Mice, Inbred BALB C , Mice, Nude , Pancreatic Neoplasms , Drug Therapy , Platelet Endothelial Cell Adhesion Molecule-1 , Genetics , Metabolism , Ribonuclease, Pancreatic , Genetics , Metabolism
4.
Chinese Journal of Burns ; (6): 473-475, 2015.
Article in Chinese | WPRIM | ID: wpr-327373

ABSTRACT

Angiogenin, as a member of the ribonuclease superfamily, is an angiogenic protein. The angiogenic ability of angiogenin plays an important role in many physical and pathological processes. Angiogenin can induce endothelial cell migration, proliferation, tubulation, as well as inhibition of cellular apoptosis. Angiogenin can be used to modulate the angiogenetic process of tissue engineered constructions via local delivery. Furthermore, angiogenin can also be regarded as a biomarker for diagnostic evaluation of malignancy, or as a target for cancer therapy. This paper presents a comprehensive overview of the angiogenic mechanisms of angiogenin, as well as its potential application in the process of wound healing and treatment of ischemic diseases and malignancy.


Subject(s)
Humans , Cell Movement , Neovascularization, Pathologic , Neovascularization, Physiologic , Ribonuclease, Pancreatic , Therapeutic Uses
5.
Chinese Journal of Otorhinolaryngology Head and Neck Surgery ; (12): 680-684, 2010.
Article in Chinese | WPRIM | ID: wpr-276404

ABSTRACT

<p><b>OBJECTIVE</b>To express, purify and refold recombinant luteinizing hormone releasing hormone-angiogenin (LHRH-Ang) toxin using E. coli. expression system.</p><p><b>METHODS</b>Recombinant LHRH-Ang expression vector was constructed by replacing of EGF fragment in plasmid pET28a/EGF-Ang with LHRH-PII fragment amplified from plasmid pET28/MSH-PE40. DNA sequencing would be used to verify the correction of fused LHRH-PII-Ang gene. Then, E. coli strain BL21 (DE3) was transformed by pET28a/LHRH-Ang vector. Expression of recombinant LHRH-Ang toxin was induced by Isopropyl-β-D-Thiogalactoside (IPTG). Refolding effects of gradient dialysis was evaluated by SDS-PAGE.</p><p><b>RESULTS</b>Prokaryotic expression vector pET28a/LHRH-Ang, containing LHRH-PII-Ang fusion gene, was constructed by PCR amplification, restriction enzyme digestion and ligation method. Sequence correction of fusion gene was confirmed by DNA sequencing. After IPGT induction, recombinant LHRH-Ang protein was expressed in BL21 (DE3) as inclusion body, it took 18.43% of total protein. Inclusion body was resolved in 8 mol/L urea and purified by DEAE-Sepharose FF column, the purity was 85%. Recombinant LHRH-Ang toxin was refolded and concentrated by gradient dialysis and PEG 20000, respectively.</p><p><b>CONCLUSIONS</b>Recombinant LHRH-Ang protein was expressed in E. coli and refolded successfully.</p>


Subject(s)
Escherichia coli , Metabolism , Gene Expression , Genetic Vectors , Gonadotropin-Releasing Hormone , Genetics , Plasmids , Recombinant Fusion Proteins , Genetics , Ribonuclease, Pancreatic , Genetics
6.
Journal of Experimental Hematology ; (6): 11-14, 2010.
Article in Chinese | WPRIM | ID: wpr-328582

ABSTRACT

The aim of study was to investigate the expression of angiogenin-2 (Ang-2) and vascular endothelial growth factor (VEGF) expression in acute leukemia (AL) and its significance in the angiogenesis and progress of AL. Serum levels of Ang-2 and VEGF in 24 de novo, 18 complete remitted (CR), 7 unremitted, 13 relapsed patients with AL were measured by enzyme-linked immunosorbent assay (ELISA), and compared with those of normal controls. The results showed that the serum levels of Ang-2 and VEGF in de novo, unremitted and relapsed patients were significantly higher than those in normal controls (p < 0.01). Compared with de novo group, the serum levels of Ang-2 and VEGF in CR patients decreased significantly, but showing no significant difference from those in normal controls (p > 0.05). In relapsed patients, the serum levels of Ang-2 and VEGF were obviously higher than those in unremitted and CR patients (p < 0.01). It is concluded that the expressions of Ang-2 and VEGF are closely related with occurrence and development of acute leukemia, the VEGF may regulate Ang-2 expression and promote angiogenesis and acute leukemia development. Preventing expressions of Ang-2 and VEGF may seem as targets for leukemia therapy in the future.


Subject(s)
Adolescent , Adult , Aged , Child , Female , Humans , Male , Middle Aged , Young Adult , Acute Disease , Case-Control Studies , Leukemia, Myeloid, Acute , Metabolism , Pathology , Neovascularization, Pathologic , Pathology , Ribonuclease, Pancreatic , Metabolism , Vascular Endothelial Growth Factor A , Metabolism
7.
Asian Journal of Andrology ; (6): 240-251, 2009.
Article in English | WPRIM | ID: wpr-284700

ABSTRACT

To explore the functions of human ribonuclease 9 (RNase 9), we constructed a mammalian fusion expression vector pcDNA-hRNase9, prepared recombinant human RNase 9-His fusion protein from HEK293T cells and determined its N-terminal amino acid sequences. According to the determined mature protein, recombinant human RNase 9 was prepared in E. coli. Ribonucleolytic activity and antibacterial activity of recombinant human RNase 9 were detected, and the distribution of human RNase 9 on tissues and ejaculated spermatozoa and in vitro capacitated spermatozoa were analyzed via indirect immunofluorescence assay. The results showed that recombinant human RNase 9 did not exhibit detectable ribonucleolytic activity against yeast tRNA, but exhibited antibacterial activity, in a concentration/time dependent manner, against E. coli. Immunofluorescent analyses showed that the predicted human RNase 9 was present throughout the epididymis, but not present in other tissues examined, and human RNase 9 was also present on the entire head and neck regions of human ejaculated spermatozoa and in vitro capacitated spermatozoa. These results suggest that human RNase 9 may play roles in host defense of male reproductive tract.


Subject(s)
Adult , Humans , Male , Young Adult , Amino Acid Sequence , Anti-Infective Agents , Metabolism , Blotting, Western , Cloning, Molecular , Enzyme-Linked Immunosorbent Assay , Epididymis , Escherichia coli , Genetic Vectors , Molecular Sequence Data , Recombinant Fusion Proteins , Chemistry , Metabolism , Ribonuclease, Pancreatic , Metabolism , Ribonucleases , Chemistry , Metabolism , Seminal Plasma Proteins , Chemistry , Metabolism , Spermatozoa , Metabolism , Testis
8.
Medical Journal of Cairo University [The]. 2009; 77 (1): 479-484
in English | IMEMR | ID: emr-100959

ABSTRACT

Acute coronary syndrome [ACS] represents a life threatening manifestation of atherosclerosis usually precipitated by acute thrombosis, induced by a ruptured or eroded atherosclerotic plaque, with or without concomitant vasoconstriction. Angiogenesis is a complex biological process that has precise coordination of multiple steps. Angiogenin is a potent angiogenic growth factor related to endothelial cell proliferation. This work tried to asses angiogenin as biochemical marker contributing to the pathophysiology of ACS and its prognostic value in adverse events of ACS. This study included 23 patients of ACS. Ten patients were in disease controls group and another twelve as healthy controls. The results revealed markedly elevated angiogenin levels in acute coronary syndrome compared to the controls [Disease group and healthy control group] p<0.0001. No significant difference in angiogenin levels between the disease control and the healthy controls. Angiogenin was high in those patients with adverse outcomes. Plasma angiogenin levels were significantly increased in ACS. Angiogenin may be involved in the pathogenesis of ACS and may have prognostic value to predict adverse events


Subject(s)
Humans , Male , Female , Biomarkers , Ribonuclease, Pancreatic , Angiogenesis Inducing Agents
9.
Journal of Korean Medical Science ; : 802-807, 2008.
Article in English | WPRIM | ID: wpr-37039

ABSTRACT

Angiogenin, a potent inducer of angiogenesis, is expressed in human endometrium. This study was performed to compare the expression of angiogenin mRNA level in the eutopic endometrium from women with and without endometriosis. Thirty-two women with advanced stage endometriosis and 29 control women were recruited. Following isolation of total RNA from endometrial tissue and reverse transcription, cDNA samples were amplified by real time polymerase chain reaction to quantify the expression of angiogenin genes. In selected patients, immunohistochemical staining was utilized to localize the area of angiogenin expression. Angiogenin mRNA level was significantly lower in the endometriosis group than in the control group during the secretory phase, especially the mid-secretory phase, and the decline was observed mainly in the women who presented with infertility. Within the endometriosis group, angiogenin mRNA levels did not differ between the proliferative and secretory phases, but, in the control group, the level in the secretory phase was higher than that during the proliferative phase. Immunohistochemistry showed that the glandular epithelial cell layer was decorated positively in both groups. These findings suggest that the relative deficiency of angiogenin expression in the secretory endometrium could impair implantation in women with advanced stage endometriosis.


Subject(s)
Adult , Female , Humans , Endometriosis/metabolism , Endometrium/metabolism , Fertility , Gene Expression Regulation , Immunohistochemistry/methods , Menstrual Cycle , Models, Biological , RNA, Messenger/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Ribonuclease, Pancreatic/biosynthesis
10.
Journal of Experimental Hematology ; (6): 667-670, 2008.
Article in Chinese | WPRIM | ID: wpr-267914

ABSTRACT

This study was purposed to investigate the angiogenin (ANG) expression in COS-7 cells and its biological activity. The gene of angiogenin was obtained from mononuclear cells of peripheral blood by using RT-PCR and inserted into eukaryotic expression vector of pcDNA3.1. After being transfected into COS-7 cells, the recombinant ANG was identified by Western blot assay. The function of promoting proliferation of ANG to ECV304 cells was detected by MTT method, and its activity of vascularization was analyzed by chick embryo chorioallantois treated by the culture supernatant after transfection with pcDNA3.1-ang. The result showed that recombinant ANG was expressed in COS-7 cells after transfection for 24 to 36 hours. It could specifically react with monoclonal antibody against ANG. The recombinant ANG could obviously promote the proliferation of ECV304 cells. In contrast with the control group, the culture supernatant of pcDNA3.1-ang transfected group could stimulate the angiogenesis in embryo chorioallantois. It is concluded that the ang transiently expresses in COS-7 cells, and its expression product obviously stimulates the cell proliferation and angiogenesis.


Subject(s)
Animals , Humans , Angiogenesis Inducing Agents , Pharmacology , COS Cells , Metabolism , Cell Line , Cell Proliferation , Chlorocebus aethiops , Endothelial Cells , Cell Biology , Genetic Vectors , Genetics , Recombinant Fusion Proteins , Genetics , Pharmacology , Ribonuclease, Pancreatic , Genetics , Pharmacology , Transfection
11.
Chinese Journal of Experimental and Clinical Virology ; (6): 504-506, 2008.
Article in Chinese | WPRIM | ID: wpr-332452

ABSTRACT

<p><b>OBJECTIVE</b>Establish the fluorescent quantitative RT-PCR detection method for rabies virus (RV) and construct RNase-resistant virus-like particles as positive controls.</p><p><b>METHODS</b>Analyze the database in GenBank, the probe and the primers were designed in the conservative region of N gene of rabies virus and the method of real-time fluorescent quantitative PCR was obtained; On the basis of MS2 phage, with the technology of gene recombination, prepare the RNase-resistant virus-like particles for RV positive controls;</p><p><b>RESULTS</b>RNase-resistant virus-like particles were obtained after prokaryotic expression in E. coli. The designed primers and probe were confirmed to be very specific and conservative, and be sensitive to-concentration of 15 copies/microl.</p><p><b>CONCLUSION</b>Established the method of detecting rabies virus by reverse transcription real-time quantitative PCR,obtained the RNase-resistant and no infectivity virus-like particles as positive controls of rabies virus.</p>


Subject(s)
Animals , Dogs , Humans , DNA Probes , DNA, Viral , RNA, Viral , Rabies , Virology , Rabies virus , Chemistry , Reverse Transcriptase Polymerase Chain Reaction , Methods , Ribonuclease, Pancreatic , Metabolism , Viral Load
12.
Indian J Biochem Biophys ; 2007 Feb; 44(1): 19-25
Article in English | IMSEAR | ID: sea-27233

ABSTRACT

Structural stability of thermophilic archaeon Sulfolobus acidocaldarius ribosomes, with respect their susceptibility to pancreatic RNase A and stability to temperature (deltaTm), on treatment with various stabilizing (polyamines) and destabilizing (sulfhydryl and intercalating) agents were studied and compared with mesophilic E. coli ribosomes, to understand the structural differences between thermophilic and mesophilic ribosomes. Thermophilic archaeal ribosomes and their subunits were 10-times less susceptible to pancreatic RNase A, compared to mesophilic ribosomes, showing the presence of strong and compact structural organization in them. Thermophilic ribosomes treated with destabilizing agents, such as sulfhydryl reagents [5,5'-Dithio-bis-(2-nitrobenzoic acid), N-ethylmaleimide and p-hydroxymercurybenzoate) and intercalating agents (ethidium bromide, EtBr) showed higher stability to RNase A, compared to similarly treated mesophilic ribosomes, indicating the unavailability of thiol-reactive groups and the presence of strong solvent inaccessible inner core. Higher stability of thermophilic ribosomes compared to mesophilic ribosomes to unfolding agents like urea further supported the presence of strong inner core particle. Thermophilic ribosomes treated with intercalating agents, such as EtBr were less susceptible to RNase A, though they bound to more reagent, showing the rigidity or resilience of their macromolecular structure to alterations caused by destabilizing agents. Overall, these results indicated that factors such as presence of strong solvent inaccessible inner core and rigidity of ribosome macromolecular structure contributed stability of thermophilic ribosomes to RNase A and other destabilizing agents, when compared to mesophilic ribosomes.


Subject(s)
Escherichia coli/chemistry , Ribonuclease, Pancreatic , Ribosomes/chemistry , Sulfolobus acidocaldarius/chemistry , Thermodynamics
13.
Chinese Acupuncture & Moxibustion ; (12): 129-133, 2007.
Article in Chinese | WPRIM | ID: wpr-351942

ABSTRACT

<p><b>OBJECTIVE</b>To explore the mechanism of electroacupuncture (EA) in improving ischemic stroke.</p><p><b>METHODS</b>A Wistar rat model of focal cerebral ischemia reperfusion was made by filament occlusion. The rats were randomly divided into a normal group, a model group, an EA group. EA was given at bilateral "Hegu" (LI 4) in the EA group. Vascular endothelial growth factor (VEGF) mRNA was detected with in situ hybridization and expression of angiogenin-1 (Ang-1) and endostatin proteins with immunohistochemical method.</p><p><b>RESULTS</b>The expressions of angiogenic growth factors including VEGF and Ang-1 in the EA group were significantly increased, while the expressions of endostatin was significantly decreased as compared with those in the model group (both P<0.05).</p><p><b>CONCLUSION</b>EA improving ischemic stroke is carried out possibly through up-regulating the expression of angiogenic growth factors and down-regulating the expression of antiangiogenic growth factors.</p>


Subject(s)
Animals , Male , Rats , Brain , Metabolism , Brain Ischemia , Metabolism , Therapeutics , Electroacupuncture , Endostatins , Immunohistochemistry , RNA, Messenger , Rats, Wistar , Reperfusion , Ribonuclease, Pancreatic , Vascular Endothelial Growth Factor A , Genetics
14.
Experimental & Molecular Medicine ; : 412-418, 2007.
Article in English | WPRIM | ID: wpr-195952

ABSTRACT

To develop a novel therapeutic angiogenesis for the treatment of cardiovascular diseases, angiogenin (ANG1) was examined as a potential therapeutic gene. An adeno-associated virus (AAV)-mediated gene delivery system was used to measure the therapeutic efficacy of ANG1. Using a triple co-transfection technique, rAAV-ANG1-GFP, rAAV- VEGF-GFP and rAAV-GFP vectors were produced, which were then used to infect human umbilical vein endothelial cells (HUVECs) in order to evaluate in vitro angiogenic activities. Their protein expressions, tagged with green fluorescent protein (GFP), were monitored by confocal microscopy. The functional activities were measured using wound-healing HUVEC migration assays. The number of migrated cells stimulated by both the expressed ANG1 and the VEGF in rAAV-infected HUVECs increased almost twice the number observed in the expressed GFP control. In vivo angiogenic activities of the expressed ANG1 or VEGF were determined using mouse angiogenesis assays. The angiogenic activities of ANG1 or VEGF expressed in the injected mice were increased by 1.36 and 2.16 times, respectively, compared to those of the expressed GFP control. These results demonstrate that the expressed ANG1 derived from rAAV infection has in vitro and in vivo angiogenic activities and suggest that the rAAV-ANG1 vector is a potential strategy for therapeutic angiogenesis.


Subject(s)
Animals , Humans , Male , Mice , Cell Movement , Cells, Cultured , Dependovirus/genetics , Endothelial Cells/metabolism , Gene Transfer Techniques , Genetic Vectors , Mice, Inbred C57BL , Neovascularization, Physiologic , Ribonuclease, Pancreatic/biosynthesis , Umbilical Veins/cytology , Vascular Endothelial Growth Factor A/biosynthesis
15.
Biosci. j ; 21(2): 77-81, May-Aug. 2005. ilus, tab, graf
Article in English | LILACS | ID: lil-430568

ABSTRACT

Este trabalho objetivou investigar a dependência entre o equilíbrio de desenovelamento da invertase por uréia, segundo um mecanismo de equilíbrio entre dois estados, com algumas propriedades termodinâmicas do solvente. Os valores das propriedades termodinâmicas do solvente foram calculados com aplicação da teoria de McMillian-Mayer. O equilíbrio de desenovelamento da invertase foi acompanhado por titulação espectrofotométrica em 280nm com uma solução de uréia a 8 mol.L-¹. O bom ajuste a um modelo de primeira ordem apresentado pelos dados de equilíbrio da invertase, bem como da RNase A e da RNase T1, é consistente com a idéia de que o alto conteúdo em carboidratos da invertase não afeta o mecanismo geral de desenovelamento. Entretanto, um aumento na concentração de uréia produziu uma diminuição na energia livre de desenovelamento (DeltaG°U ) para a intertase, e um aumento nos valores de DeltaG°U para Rnase A e Rnase T1. A invertase também exigiu maiores valores de atividade de água (Aw) do que a RNAse A e a RNAse T1 para ser desenovelada. O diferente comportamento da invertase em relação a aquelas enzimas pode ser relevante para fornecer informação adicional sobre os mecanismos detalhados do enovelamento e desenovelamento de proteínas.


Subject(s)
Ribonuclease T1 , Ribonuclease, Pancreatic , Ribonucleases , Solvents , Thermodynamics , Urea , Water
16.
Benha Medical Journal. 2004; 21 (1): 71-83
in English | IMEMR | ID: emr-172728

ABSTRACT

Abnormal angiogenesis is reported in patients with con-heart diseases [CHD]. Angiogenic growth factors play an important role in the regulation of angiogenesis. This study was done to assess angiogenin [ANG] levels in children with CHD, its correlation with degree of hypoxaemia and its relation to the development of pulmonary hypertension [PH]. Serum ANG level was assessed by sandwich .enzyme immunoassay technique in 36 children with cyanotic congenital, heart diseases [CCHD] and in 35 children with acyanotic congenital heart diseases [ACHD]. Both groups were compared to 12 healthy controls of matched age and sex. CCHD patients had higher serum ANG levels compared to ACHD [177.8 +/- 53.7 Vs 149.4 . +/- 51.2 ng/ml, P=0.02] and controls m8 +/- 53.7 Vs 114.8 +/- 51.8 ng/ml, P 0.002]. A1VG was negatively correlated with pO2 and O2 saturation [r =-0.46, p=0.004 and r =-0.403, p 0.015; respectively]. AATG level in ACHD was not significantly different from controls [149.4 +/- 51.2 Vs 114.8 +/- 51.8 ng/ml, P=0.06]. In ACHD, patients with PH had significantly elevated ANG levels when compared to without PH [188.9 +/- 48,7 Vs 137.7 . +/- 46.6 ng/ml, P=0.011 and to controls [1 88.9 +/- 48.7 V 114.8 +/- 51.8 ng/ml, P=0.005]. Increased ANG in CCHD-secondary to hypoxemia-may responsible for abnormal angiogenesis in these patients. Increased ANG levels in ACHD patients with PH may be a compensatory mechanism aiming for neovasculrization distal to the site of pulmonary vascular obstruction


Subject(s)
Humans , Male , Female , Ribonuclease, Pancreatic/blood , Angiogenesis Inducing Agents/blood , Hypertension, Pulmonary/etiology , Hypoxia/etiology , Child , Echocardiography/methods
17.
Indian J Biochem Biophys ; 2001 Feb-Apr; 38(1-2): 27-33
Article in English | IMSEAR | ID: sea-27464

ABSTRACT

Angiogenin is a protein belonging to the superfamily of RNase A. The RNase activity of this protein is essential for its angiogenic activity. Although members of the RNase A family carry out RNase activity, they differ markedly in their strength and specificity. In this paper, we address the problem of higher specificity of angiogenin towards cytosine against uracil in the first base binding position. We have carried out extensive nano-second level molecular dynamics(MD) computer simulations on the native bovine angiogenin and on the CMP and UMP complexes of this protein in aqueous medium with explicit molecular solvent. The structures thus generated were subjected to a rigorous free energy component analysis to arrive at a plausible molecular thermodynamic explanation for the substrate specificity of angiogenin.


Subject(s)
Animals , Cattle , Cytidine Monophosphate/chemistry , Ligands , Models, Chemical , Models, Molecular , Protein Binding , Ribonuclease, Pancreatic/chemistry , Substrate Specificity , Thermodynamics , Uridine Monophosphate/chemistry
18.
Experimental & Molecular Medicine ; : 203-209, 1999.
Article in English | WPRIM | ID: wpr-158704

ABSTRACT

Angiostatin is a potent angiogenesis inhibitor that is composed of the first four kringles of plasminogen fragment. Angiostatin with one less kringle molecule (kringle 1 to 3) was recently demonstrated to be an effective angiogenic inhibitor. To determine whether recombinant plasminogen kringle 1-3 (rPK1-3) can inhibit the corneal neovascularization induced by potent angiogenic factors; angiogenin, bFGF, or VEGF, hydron polymer discs each containing 2.0 microg of angiogenin, 500 ng of bFGF, or 500 ng of VEGF respectively were implanted into the corneal stroma of 138 rabbit eyes, and then discs each containing 10 microg, 12.5 microg, 20 microg or 30 microg of rPK1-3 were implanted randomly. Discs containing phosphate buffered saline were also implanted as a control. The angiogenesis score on number and length of newly formed vessels on the each of the rabbit's cornea were recorded daily by two observers (blinded). The treated corneas were also examined histologically. Recombinant PK1-3 treated corneas showed less neovascularization induced by all angiogenic factors (p < 0.05). and the extent of inhibition of neovascularization was proportional to the concentration of rPK1-3 (p < 0.05). Histologic examination showed leukocyte infiltration into the corneal stroma on the PBS treated eyes whereas rPK1-3 treated eyes showed only traces of leukocytes. These results of the effective rPK1-3 inhibition of corneal neovascularization induced by angiogenin, bFGF, or VEGF suggest that this angiostatin related fragment, rPK1-3, may be useful in the treatment of various neovascular diseases. Copyright 2000 Academic Press.


Subject(s)
Chick Embryo , Rabbits , Angiogenesis Inhibitors/pharmacology , Angiogenesis Inhibitors/genetics , Animals , Chorion/drug effects , Chorion/blood supply , Cornea/pathology , Cornea/drug effects , Cornea/blood supply , Endothelial Growth Factors/pharmacology , Fibroblast Growth Factor 2/pharmacology , Kringles/genetics , Lymphokines/pharmacology , Microscopy/methods , Neovascularization, Pathologic/drug therapy , Plasminogen/pharmacology , Plasminogen/genetics , Recombinant Proteins/pharmacology , Recombinant Proteins/genetics , Ribonuclease, Pancreatic/pharmacology
19.
Korean Journal of Medicine ; : 615-626, 1998.
Article in Korean | WPRIM | ID: wpr-196292

ABSTRACT

OBJECTIVE: Activities of nucleases (acid DNase and neutral RNase) and RNase inhibitor known to be involved in carcinogenesis and suppression of cancer were determined in cancer tissue, serum and ascitic fluid of patients with hepatocellular carcinoma and were compared with those of the controls. Also studied were nucleases and RNase inhibitor isolated from hepatocellular carcinoma tissue and ascitic fluid of the cancer patients to evaluate the properties and interactions between them. METHOD: Activities of nucleases and RNase inhibitor were measured in cancer tissue, serum and ascitic fluid of patients with hepatocellular carcinoma by ultraviolet spectrophotometry. Nucleases and RNase inhibitor were isolated from hepatocellular carcinoma tissue and ascitic fluid of the cancer patients by DEAE-cellulose column chromatography. As controls, normal tissue of the cancer patients, serum of healthy persons and ascitic fluid of cirrhotic patients were used. RESULT: Activities of DNase, RNase and RNase inhibitor were significantly increased in hepatocellular carcinoma tissue. DNase activity was not detected, RNase activity was increased and RNase inhibitor activity was unchanged in both serum and ascitic fluid of the hepatocellular carcinoma patients. DNase was isolated as a single enzyme and RNase as seven isozymes from the hepatocellular carcinoma tissue. The DNase isolated preferentially cleaved ds DNA over ss DNA and was endonuclease in nature (majority of hydrolytic products of DNA by the DNase were oligodeoxyribonucleotides). Of seven RNase isozymes isolated from the hepatocellular carcinoma tissue, isozyme I exhibited nonsecretory nature of RNase and other six isozymes secretory nature of the enzyme. Activity of RNase isozyme V was greatly increased and the activity of inhibitor complexed with the isozyme V was also increased. RNase in ascitic fluid of the cancer patient was separated into four isozymes, of which isozyme I exhibited mixed form of secretory and nonseretory nature and greatly increased in its activity. RNase isozyme V isolated in the hepatocellular carcinoma tissue was not detected in the ascitic fluid. CONCLUSION: The use of the nucleases and the inhibitor in the cancer tissue as biochemical markers for the hepatocellular carcinoma was suggested. RNase was released into the body fluid from the cancer tissue and could be used as a diagnostic marker for the hepatocellular carcinoma. An important role of the DNase in carcinogenesis of the liver was suggested. RNase isozyme V was limited in the cancer tissue and RNase isozyme I and V and inhibitors associated with these isozymes might be involved in carcinogenesis processes, suppression of cancer and maintenance of hepatocellular carcinoma through their interactions.


Subject(s)
Humans , Ascitic Fluid , Biomarkers , Body Fluids , Carcinogenesis , Carcinoma, Hepatocellular , Chromatography , DEAE-Cellulose , Deoxyribonucleases , DNA , Isoenzymes , Liver , Ribonuclease, Pancreatic , Ribonucleases , Spectrophotometry, Ultraviolet
20.
Journal of the Korean Cancer Association ; : 231-241, 1998.
Article in Korean | WPRIM | ID: wpr-188254

ABSTRACT

PURPOSE: We determined the clinical significance of telomerase activity and telomere length in breast cancer patients and also developed the measuring system of telomerase activity change with RNAse A pre-treatment. MATERIALS AND METHODS: We measured the telomerase activity in 71 breast cancer tissues and paired normal tissues with TRAP (Telomeric Repeat Amplification Protocol) assay. Telomerase activity was calculated by computer-assisted densitometry compared to telomerase activity of the 293 control cell line. To develop the measuring system of telomerase activity modulation, we measured the telomerase activity after the treatment with RNAse A, 150microgram/ml, which inhibited 70% of telomerase activity compared to control in the 293 control cell line. In 59 paired tissues with telomerase activity, terminal restriction fragment (TRFs) length were measured using Southern blotting. RESULTS: Sixty-three out of 71 cancer tissues showed telomerase activity (88.7%), while no telomerase activity was detected in their paired normal tissues. Telomerase activity was correlated to the node metastasis (p=0.02) and stage (p=0.005), but not to the tumor size or the hormonal receptor status. TRFs were neither specific to tumor tissues nor related to any of the clinical parameters. However, changes of TRFs of the tumor tissues from their paired normal tissues were correlated to the telomerase activities. Also the patients with different TRFs between cancer and normal tissues were in more advanced stage. After pre-treatment with the 150microgram/ml of RNAse A, telomerase activity in the tumor tissues showed variable inhibition. Relative inhibition, the ratio of inhibited telomerase activity in each tumor tissue compared to the inhibition of 293 control cell line, was proportional to the telomerase activity. CONCLUSION: In breast cancer, telomerase activity was specific to the tumor tissues and correlated to tumor progression. A combination of telomerase activity and TRFs changes can be used as a guidline in detecting a better candidate for telomerase inhibition. Semi-quantitative assay with RI system can be used in evaluating the changes of telomerase activity after treatment with a new telomerase inhibitor with TRAP assay.


Subject(s)
Humans , Biological Therapy , Blotting, Southern , Breast Neoplasms , Breast , Cell Line , Densitometry , Neoplasm Metastasis , Ribonuclease, Pancreatic , Telomerase , Telomere
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