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1.
Rev. fitoter ; 19(1): 5-13, mar. 2021. tab, graf, ilus
Article in Spanish | IBECS | ID: ibc-202035

ABSTRACT

El rizoma de cúrcuma es una conocida especia proveniente del sudeste asiático que se utiliza ampliamente en la medicina ayurvédica para el tratamiento de patologías ginecológicas, alteraciones hepáticas, enfermedades infecciosas o alteraciones dermatológicas tales como psoriasis, dermatitis o acné. En la actualidad está cobrando especial interés por su efecto antiinflamatorio y antioxidante, sirviendo de base para el uso de esta planta medicinal en el tratamiento de patologías que cursan con inflamación o estrés oxidativo. En este sentido el rizoma de cúrcuma se ha propuesto como tratamiento del síndrome metabólico, cuya prevalencia está creciendo en los últimos años y que se caracteriza por la presencia de patologías subyacentes como son la obesidad, la diabetes, las dislipemias y la hipertensión arterial. Esta revisión recoge el potencial terapéutico de la cúrcuma en el síndrome metabólico en base a las evidencias obtenidas en diversos estudios clínicos y preclínicos


Turmeric rhizome, a well-known spice from the southeast of Asia, is widely used in. Ayurvedic medicine for the treatment of gynecological pathologies, liver disorders, infectious diseases or dermatological disorders such as psoriasis, dermatitis or acne. Currently, it is gaining interest due to its antiinflammatory and antioxidant effect, serving as the basis for the use of this plant in inflammatory diseases or pathologies that occur with oxidative stress. Turmeric rhizome has been proposed as a treatment for metabolic syndrome, which has an increasing prevalence in the last years and is characterized by a combination of underlying pathologies such as obesity, diabetes, dyslipidemia and hypertension. This paper aims to review the therapeutic potential of turmeric rhizome in metabolic syndrome, based on the evidences obtained from clinical and preclinical studies


O rizoma de cúrcuma, uma especiaria bem conhecida do sudeste da Ásia, é amplamente utilizado na medicina ayurvédica para o tratamento de patologias ginecológicas, doenças hepáticas e doenças infecciosas ou dermatológicas, como psoríase, dermatite ou acne. Atualmente, assiste-se a um crescente interesse na sua utilização, principalmente devido ao seu efeito antiinflamatório e antioxidante, que suportam a utilização desta planta em doenças inflamatórias ou patologias que ocorrem devido ao stress oxidativo. O rizoma de cúrcuma tem sido proposto como tratamento para a síndrome metabólica, que apresenta prevalência crescente nos últimos anos e é caracterizada por uma combinação de patologias de base, como obesidade, diabetes, dislipidemia e hipertensão.Este trabalho tem como objetivo fazer uma revisão do potencial terapêutico do rizoma de cúrcuma na síndrome metabólica com base nas evidências obtidas em estudos clínicos e pré-clínicos publicados na literatura científica


Subject(s)
Humans , Metabolic Syndrome/therapy , Curcumin/therapeutic use , Anti-Inflammatory Agents/therapeutic use , Diabetes Mellitus, Type 2/therapy , Antioxidants/therapeutic use , Medicine, Ayurvedic/methods , Curcuma , Obesity/therapy , Dyslipidemias/therapy , Tumor Necrosis Factor-alpha/chemical synthesis
2.
Bioorg Med Chem ; 25(18): 4946-4952, 2017 09 15.
Article in English | MEDLINE | ID: mdl-28651912

ABSTRACT

The scope of chemical protein synthesis (CPS) continues to expand, driven primarily by advances in chemical ligation tools (e.g., reversible solubilizing groups and novel ligation chemistries). However, the design of an optimal synthesis route can be an arduous and fickle task due to the large number of theoretically possible, and in many cases problematic, synthetic strategies. In this perspective, we highlight recent CPS tool advances and then introduce a new and easy-to-use program, Aligator (Automated Ligator), for analyzing and designing the most efficient strategies for constructing large targets using CPS. As a model set, we selected the E. coli ribosomal proteins and associated factors for computational analysis. Aligator systematically scores and ranks all feasible synthetic strategies for a particular CPS target. The Aligator script methodically evaluates potential peptide segments for a target using a scoring function that includes solubility, ligation site quality, segment lengths, and number of ligations to provide a ranked list of potential synthetic strategies. We demonstrate the utility of Aligator by analyzing three recent CPS projects from our lab: TNFα (157 aa), GroES (97 aa), and DapA (312 aa). As the limits of CPS are extended, we expect that computational tools will play an increasingly important role in the efficient execution of ambitious CPS projects such as production of a mirror-image ribosome.


Subject(s)
Computational Biology/methods , Proteins/chemical synthesis , Software , Chaperonin 10/chemical synthesis , Chaperonin 10/chemistry , Chaperonin 60/chemical synthesis , Chaperonin 60/chemistry , Escherichia coli/metabolism , Proteins/chemistry , Ribosomal Proteins/chemical synthesis , Ribosomal Proteins/chemistry , Tumor Necrosis Factor-alpha/chemical synthesis , Tumor Necrosis Factor-alpha/chemistry
3.
Org Biomol Chem ; 14(23): 5298-303, 2016 Jun 21.
Article in English | MEDLINE | ID: mdl-27211891

ABSTRACT

Tumor Necrosis Factor alpha (TNFα) is an inflammatory cytokine that plays a central role in the pathogenesis of chronic inflammatory disease. Here we describe the chemical synthesis of l-TNFα along with the mirror-image d-protein for use as a phage display target. The synthetic strategy utilized native chemical ligation and desulfurization to unite three peptide segments, followed by oxidative folding to assemble the 52 kDa homotrimeric protein. This synthesis represents the foundational step for discovering an inhibitory d-peptide with the potential to improve current anti-TNFα therapeutic strategies.


Subject(s)
Peptide Library , Tumor Necrosis Factor-alpha/chemistry , Tumor Necrosis Factor-alpha/chemical synthesis , Models, Molecular , Protein Structure, Secondary , Stereoisomerism
4.
Clín. investig. arterioscler. (Ed. impr.) ; 20(6): 233-238, nov. 2008. ilus, tab
Article in Es | IBECS | ID: ibc-70129

ABSTRACT

Introducción. Además de sus acciones fisiológicas en el ámbito renal en el equilibrio hidroelectrolítico, la aldosterona está implicada en algunas alteraciones cardiovasculares asociadas a la hipertensión arterial, como la hipertrofia ventricular, la fibrosis cardíaca, la insuficiencia cardíaca, etc. El objetivo del estudio fue evaluar el posible papel de los mineral ocorticoides en el proceso inflamatorio vascular asociado a la hipertensión en ratas. Métodos. Se utilizaron ratas macho espontáneamente hipertensas (SHR, del inglés spontaneously hypertensive rats) de 18 semanas de edad, tratadas con 2 dosis del antagonista del receptor de mineralocorticoides eplerenona, de 30y 100 mg/kg/día, durante 10 semanas. Se utilizó un grupo de SHR sin tratar como control, y un grupo de ratas Wistar Kyoto (WKY) se utilizó como grupo de referencia normotenso. Se valoró la presión arterial sistólica (PAS), las concentraciones plasmáticas de interleucina (IL) 1B e IL-6, así como la expresión aórtica del ácido ribonucleicomensajero (ARNm) de ambas, del factor de necrosis tumoral alfa (TNF-alfa), del factor de transcripción nuclear kB (NF-kB), valorando elp105 (precursor de la subunidad p50 del NF-kB) yde su inhibidor (IkB).Resultados. Las ratas SHR presentaron valores superiores de PAS respecto a las ratas WKY (p <0,05). Los valores plasmáticos de IL-1Beta e IL-6, así como su expresión génica y la del TNF-alfa, aumentaron en las SHR (p < 0,05). Asimismo, las SHR presentaron un aumento en la expresión génica del NF-kB y una disminución del IkB. Solamente el tratamiento con eplerenona 100mg/kg/día redujo significativamente los valores de PAS. Sin embargo, ambas dosis redujeron los valores plasmáticos y la expresión génica aórtica de las citocinas valoradas (p < 0,05). Asimismo, ambas dosis redujeron la expresión aórtica del (..) (AU)


Introduction. Besides its physiological role in the control of hydroelectrolyte balance at renal level, aldosterone plays an important role incardiovascular alterations associated with hypertension, such as left ventricular hypertrophy, cardiac fibrosis, congestive heart failure, etc. Th eaim of the present study was to evaluate the effect of endogenous mineral corticoids on vascular inflammation associated with hypertension in rats. Methods. Male spontaneously hypertensive rats(SHR) (18 weeks old) were treated with two doses of eplerenone (30 and 100 mg/kg/day) for 10 weeks. A group of (n = 8) untreated SHR was used as a control-vehicle group, and a group of Wistar Kyotorats (n=8) was used as a reference of (..) (AU)


Subject(s)
Animals , Rats , Mineralocorticoids/adverse effects , Mineralocorticoids/blood , Mineralocorticoids/toxicity , Hypertension/complications , Hypertension/therapy , Myocardial Infarction/epidemiology , Cytokines/analysis , Cytokines/chemical synthesis , Tumor Necrosis Factor-alpha/chemical synthesis , Tumor Necrosis Factor-alpha/pharmacology , Heart Diseases/complications , Heart Diseases/etiology , Aldosterone/analysis , Aldosterone/toxicity , Myocardial Infarction/mortality , Myocardial Infarction/therapy
5.
J Control Release ; 129(3): 179-86, 2008 Aug 07.
Article in English | MEDLINE | ID: mdl-18547669

ABSTRACT

Numerous antagonists of tumor necrosis factor alpha (TNFalpha) have been developed to attenuate inflammation and accompanying pain in many disease processes. Soluble TNF receptor type II (sTNFRII) is one such antagonist that sequesters TNFalpha away from target receptors and attenuates its activity. Systemic delivery of soluble TNF receptors or other antagonists may have deleterious side effects associated with immune suppression, so that strategies for locally targeted drug delivery are of interest. Elastin-like polypeptides (ELPs) are biopolymers capable of in situ drug depot formation through thermally-driven supramolecular complexes at physiological temperatures. A recombinant fusion protein between ELP and sTNFRII was designed and evaluated for retention of bivalent functionality. Thermal sensitivity was observed by formation of supramolecular submicron-sized particles at 32 degrees C, with gradual resolubilization from the depot observed at physiological temperatures. In vitro refolding of the sTNFRII domain was required and the purified product exhibited an equilibrium dissociation constant for interacting with TNFalpha that was seven-fold higher than free sTNFRII. Furthermore, anti-TNF activity was observed in inhibiting TNFalpha-mediated cytotoxicity in the murine L929 fibrosarcoma assay. Potential advantages of this ELP-sTNFRII fusion protein as an anti-TNFa drug depot include facility of injection, in situ depot formation, low endotoxin content, and functionality against TNFalpha.


Subject(s)
Tumor Necrosis Factor-alpha/antagonists & inhibitors , Tumor Necrosis Factor-alpha/chemical synthesis , Animals , Elastin/chemistry , Elastin/genetics , Elastin/metabolism , Escherichia coli/genetics , Fibrosarcoma/metabolism , Fibrosarcoma/pathology , Humans , Inhibitory Concentration 50 , Kinetics , L Cells , Mice , Peptides/chemistry , Peptides/metabolism , Protein Renaturation , Protein Structure, Tertiary , Receptors, Tumor Necrosis Factor, Type II/chemistry , Receptors, Tumor Necrosis Factor, Type II/genetics , Receptors, Tumor Necrosis Factor, Type II/metabolism , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/metabolism , Solubility , Temperature , Tumor Necrosis Factor-alpha/chemistry
6.
J Immunol ; 180(12): 8176-83, 2008 Jun 15.
Article in English | MEDLINE | ID: mdl-18523283

ABSTRACT

The inflammatory and proapoptotic cytokine TNF possesses a compelling potential as an antitumoral therapeutic agent. Possible target cells include the malignant cells themselves, the tumor vasculature, or the immune system. As the clinical use of TNF is limited by systemic toxicity, targeting strategies using TNF-based fusion proteins are currently used. A major obstacle, however, is that homotrimeric TNF ligands are prone to activity loss due to dissociation into their monomers. In this study, we report the construction of single-chain TNF molecule, a TNF mutant consisting of three TNF monomers fused by short peptide linkers. In comparison to wild-type TNF, single-chain TNF was found to possess increased stability in vitro and in vivo, displayed reduced systemic toxicity yet slightly enhanced antitumoral activity in mouse models. Creation of single-chain variants is a new approach for improvement of functional activity of therapeutics based on TNF family ligands.


Subject(s)
Antineoplastic Agents/chemical synthesis , Thermodynamics , Tumor Necrosis Factor-alpha/chemical synthesis , Tumor Necrosis Factor-alpha/physiology , Animals , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Cell Line, Transformed , Cell Line, Tumor , Cells, Cultured , Female , Humans , Mice , Mice, Inbred BALB C , Mice, Inbred C3H , Mice, Knockout , Protein Binding/genetics , Protein Binding/immunology , Protein Denaturation , Receptors, Tumor Necrosis Factor, Type I/deficiency , Receptors, Tumor Necrosis Factor, Type I/genetics , Receptors, Tumor Necrosis Factor, Type II/deficiency , Receptors, Tumor Necrosis Factor, Type II/genetics , Recombinant Proteins/administration & dosage , Recombinant Proteins/adverse effects , Recombinant Proteins/chemical synthesis , Tumor Necrosis Factor-alpha/adverse effects
7.
Bioconjug Chem ; 18(1): 41-9, 2007.
Article in English | MEDLINE | ID: mdl-17226956

ABSTRACT

PEGylation is a procedure of growing interest for enhancing the therapeutic and biotechnological potential of peptides and proteins. Transferrin (Tf) has been proposed to be useful for targeting cancer cells. The aim of this study was to modify PEGylated recombinant human tumor necrosis factor alpha (PEG-TNF-alpha) with Tf to form Tf-PEG-TNF-alpha conjugates, which would maintain the advantages of PEGylation and also achieve the function of active targeting to tumor cells. In PEGylation reactions with 5-, 20-, 40-, and 60-fold molar excess of 3.4 kDa N-hydroxysuccinimide-PEG-maleimide (PT1, PT2, PT3, and PT4, respectively), PEG-TNF-alpha conjugates with different PEG chains were synthesized. A perfusion chromatography technique using a cation-exchange column was introduced to purify PEG-TNF-alpha conjugates. PT4 with about five PEG chains was selected as a lead candidate due to highest extent of PEGylation and maximum reaction yield. Thiolated Tf was conjugated to the maleimide group at the distal end of the PEG chains on the PEG-TNF-alpha conjugates, with the resulting Tf-PEG-TNF-alpha conjugates after purification containing approximately one Tf ligand on one TNF-alpha molecule. The conjugate of Tf and PT4 (TPT4) was selected to assess the specificity and affinity to transferrin receptor (TfR) on two kinds of tumor cells, K562 and KB. Both the receptor binding assays and the competition experiments were performed using radioligand binding analysis. The results demonstrated that TPT4 as well as Tf bound specifically to the TfR on the tumor cell surface and the affinity of the conjugate to TfR was similar to that of native Tf. In contrast, PEG-TNF-alpha demonstrated no specificity. The biodistribution and antitumor effects were investigated in S-180 tumor-bearing mice. It was found that TPT4 could markedly alter in vivo behavioral characteristics of TNF-alpha. Compared with TNF-alpha and PT4, extravasated TPT4 in tumor tissues exhibited a significantly delayed blood clearance and the highest intratumoral TNF-alpha levels. Furthermore, the inhibitory rate of tumor of TPT4 enhanced 5.3- and 1.8-fold over that of TNF-alpha and PT4, indicating that TPT4 exhibited the highest antitumor activity. These results suggested that Tf-PEG-TNF-alpha was a useful long circulating conjugate with the capabilities of specific receptor binding resulting in enhanced antitumor activity of TNF-alpha.


Subject(s)
Drug Delivery Systems/methods , Drug Design , Propylene Glycol/chemistry , Receptors, Transferrin/metabolism , Transferrin/chemistry , Transferrin/metabolism , Tumor Necrosis Factor-alpha/pharmacology , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/metabolism , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Female , Humans , Mice , Molecular Structure , Neoplasms/drug therapy , Neoplasms/pathology , Tumor Necrosis Factor-alpha/chemical synthesis , Tumor Necrosis Factor-alpha/chemistry
8.
Sci STKE ; 2003(208): PE51, 2003 Nov 11.
Article in English | MEDLINE | ID: mdl-14612594

ABSTRACT

Site-directed mutagenesis of tumor necrosis factor (TNF) based on prediction of the interaction of specific residues with TNF receptors generated dominant-negative constructs, in which single- or double-amino acid changes result in decreased receptor binding and cellular activation. These dominant-negatives not only provide a novel manner to block the proinflammatory effects of TNF, but also can be used as a tool to examine ligand-receptor interactions and their importance in signaling. Because these TNF mutant molecules are smaller than those used for conventional anti-TNF therapies, such as etanercept or infliximab, they are likely to achieve greater tissue concentrations and may provide enhanced therapeutic effect. However, the immunogenicity, as well as efficacy, of the dominant-negative TNF constructs must be more completely examined.


Subject(s)
Computational Biology/methods , Drug Design , Genetic Variation/genetics , Inflammation Mediators/chemical synthesis , Signal Transduction/physiology , Tumor Necrosis Factor-alpha/chemical synthesis , Humans , Inflammation/prevention & control , Mutagenesis, Site-Directed/genetics , Protein Isoforms/chemical synthesis , Signal Transduction/genetics , Tumor Necrosis Factor-alpha/genetics
9.
Bioorg Med Chem Lett ; 12(20): 3009-13, 2002 Oct 21.
Article in English | MEDLINE | ID: mdl-12270195

ABSTRACT

A detailed SAR study directed toward the optimization of pharmacokinetic parameters for analogues of L-791,943 is reported. The introduction of a soft metabolic site on this structure permitted the identification of L-826,141 as a potent phosphodiesterase type 4 (PDE4) inhibitor that is well absorbed and that presents a shorter half-life than L-791,943 in a variety of animal species. The efficacy of L-826,141 is also demonstrated in different in vivo models.


Subject(s)
3',5'-Cyclic-AMP Phosphodiesterases/antagonists & inhibitors , Phosphodiesterase Inhibitors/chemical synthesis , Phosphodiesterase Inhibitors/pharmacology , Alkylation , Animals , Biological Availability , Cell Line , Cyclic Nucleotide Phosphodiesterases, Type 4 , Half-Life , Humans , Indicators and Reagents , Phosphodiesterase Inhibitors/pharmacokinetics , Pyridines/chemical synthesis , Pyridines/pharmacokinetics , Pyridines/pharmacology , Rats , Structure-Activity Relationship , Tumor Necrosis Factor-alpha/chemical synthesis , Tumor Necrosis Factor-alpha/pharmacology
10.
Int. j. lepr. other mycobact. dis ; 69(3): 225-233, Sept., 2001. ilus, tab, graf
Article in English | Sec. Est. Saúde SP, HANSEN, Hanseníase Leprosy, SESSP-ILSLACERVO, Sec. Est. Saúde SP | ID: biblio-1227054

ABSTRACT

Pentoxifylline (PTX), a phosphodiesterase inhibitor, is known to downregulate tumor necrosis factor-alpha (TNF-alpha) secretion induced by lipopolysacchride (LPS) and gamma interferon (IFN-gamma). We have had limited success in treating leprosy reactions, including erythema nodosum leprosum (ENL), in which TNF-alpha has been identified as a major proinflammatory cytokine. PTX inhibited production of NO (IC50 approximately equal to 1.0 mg/ml) and TNF-alpha (IC50 approximately equal to 0.05 mg/ml) in a dose-dependent fashion. As little as 0.5 mg/ml of PTX decreased NO production and 0.01 mg/ml of PTX inhibited TNF-alpha production. Western blot analyses demonstrated that iNOS was suppressed by PTX. Northern blot analyses showed significant reduction of TNF-alpha mRNA. We conclude that PTX is an effective inhibitor of lipoarabinomannan (LAM)-induced TNF-alpha production at both the product and transcriptional levels in our macrophage cell line. PTX also showed moderate inhibition of NO at the product level as well as translation of iNOS.


Subject(s)
Tumor Necrosis Factor-alpha/immunology , Tumor Necrosis Factor-alpha/chemical synthesis , Macrophages/immunology , Pentoxifylline/immunology , Pentoxifylline/chemical synthesis
11.
J Pharmacol Exp Ther ; 290(1): 368-72, 1999 Jul.
Article in English | MEDLINE | ID: mdl-10381801

ABSTRACT

We attempted to develop a novel method for the chemical modification of cytokines with synthetic polymers to increase in vivo therapeutic efficacy. A pH-reversible amino-protective reagent, dimethylmaleic anhydride (DMMAn), was used for polymer conjugation of tumor necrosis factor-alpha (TNF-alpha) with polyethylene glycol (PEG). The novel PEGylated TNF-alpha, PEG-TNF-alpha(+), which was pretreated with DMMAn before PEGylation, had 20% to 40% higher specific activity than PEG-TNF-alpha(-) (not treated with DMMAn) in vitro. Moreover, PEG-TNF-alpha(+) more potently caused tumor necrosis in Meth-A solid tumors in mice than did PEG-TNF-alpha(-). The middle fraction (M) of PEG-TNF-alpha(+), which was of the optimal degree of modification among PEG-TNF-alpha(+)s with different molecular weights, caused the highest degree of tumor hemorrhagic necrosis: 30-fold higher than native TNF-alpha and 2-fold higher than the most potent MPEG-TNF-alpha(-) that also had nearly the same molecular weight. Significantly, improvements in antitumor activity in vivo were more marked than were changes in specific activity. Furthermore, native TNF-alpha caused a dose-dependent body weight loss in mice, whereas no obvious side effects were observed in any PEG-TNF-alpha-treated mice. These results suggest that PEGylation using DMMAn is a useful for clinical cytokine delivery.


Subject(s)
Antineoplastic Agents/chemical synthesis , Maleic Anhydrides/chemistry , Polyethylene Glycols/chemical synthesis , Tumor Necrosis Factor-alpha/chemical synthesis , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Endopeptidases/chemistry , Female , Fibrosarcoma/drug therapy , Fibrosarcoma/pathology , Hydrolysis , Indicators and Reagents , Mice , Mice, Inbred BALB C , Neoplasm Transplantation , Polyethylene Glycols/chemistry , Polyethylene Glycols/pharmacology , Tumor Necrosis Factor-alpha/chemistry , Tumor Necrosis Factor-alpha/pharmacology
12.
Nat Med ; 5(2): 157-63, 1999 Feb.
Article in English | MEDLINE | ID: mdl-9930862

ABSTRACT

To evaluate the utility of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) as a cancer therapeutic, we created leucine zipper (LZ) forms of human (hu) and murine (mu) TRAIL to promote and stabilize the formation of trimers. Both were biologically active, inducing apoptosis of both human and murine target cells in vitro with similar specific activities. In contrast to the fulminant hepatotoxicity of LZ-huCD95L in vivo, administration of either LZ-huTRAIL or LZ-muTRAIL did not seem toxic to normal tissues of mice. Finally, repeated treatments with LZ-huTRAIL actively suppressed growth of the TRAIL-sensitive human mammary adenocarcinoma cell line MDA-231 in CB.17 (SCID) mice, and histologic examination of tumors from SCID mice treated with LZ-huTRAIL demonstrated clear areas of apoptotic necrosis within 9-12 hours of injection.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Membrane Glycoproteins/pharmacology , Tumor Necrosis Factor-alpha/pharmacology , Animals , Apoptosis Regulatory Proteins , Dose-Response Relationship, Drug , Fas Ligand Protein , Humans , Membrane Glycoproteins/administration & dosage , Membrane Glycoproteins/chemical synthesis , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, SCID , Protein Conformation , TNF-Related Apoptosis-Inducing Ligand , Tumor Cells, Cultured , Tumor Necrosis Factor-alpha/administration & dosage , Tumor Necrosis Factor-alpha/chemical synthesis
13.
Br J Cancer ; 74(7): 1090-5, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8855980

ABSTRACT

To design hybrid tumour necrosis factor-alpha (TNF-alpha) applicable to systemic anti-tumour therapeutic use, we assessed the relationships among the molecular size of hybrid TNF-alpha, in vitro bioactivity and in vivo anti-tumour potency. Natural human TNF-alpha was covalently modified with polyethylene glycol (PEG) of various number-average molecular weights (Mn = 2000, 5000, 12,000). The in vitro bioactivity of PEG-modified TNF-alpha s decreased with an increase in the degree of PEG modification, irrespective of the molecular weight of PEG. This decrease in the specific bioactivity markedly increased with an increase in the molecular weight of the attached PEG. The in vivo anti-tumour effects of the hybrid TNF-alpha s with a molecular size from 100 to 110 kDa, which had more than 50% of specific bioactivity of native TNF-alpha, were significantly superior to other PEG-TNF-alpha s. These hybrid TNF-alpha s showed over ten times greater anti-tumour effects than native TNF-alpha. Thus, the molecular size, which was determined by the degree of PEG modification and PEG molecular weight, influences the specific activity and anti-tumour effects of hybrid TNF-alpha.


Subject(s)
Antineoplastic Agents/chemical synthesis , Drug Design , Polyethylene Glycols/chemical synthesis , Tumor Necrosis Factor-alpha/chemical synthesis , Animals , Antineoplastic Agents/pharmacology , Drug Screening Assays, Antitumor , Humans , Male , Mice , Polyethylene Glycols/pharmacology , Sarcoma 180/drug therapy , Structure-Activity Relationship , Tumor Necrosis Factor-alpha/pharmacology
14.
Pept Res ; 5(6): 315-20, 1992.
Article in English | MEDLINE | ID: mdl-1283542

ABSTRACT

A fully automated instrument for multiple simultaneous peptide synthesis was constructed to provide large numbers of peptides for immunological research. The synthesis is performed in a flow-through mode with the conventional solid supports contained in 48 individual reaction columns. The instrument is based on a commercial autosampler equipped with a motor-driven syringe for accurate delivery of reagents and a robot arm carrying a dispenser needle. Dedicated software was developed to compile overlapping peptides from a given protein sequence and to control all functions of the robot. In situ activation by BOP was chosen as the optimized chemistry protocol. The peptides are cleaved from the resin in the reactors used for synthesis, thus minimizing handling. Performance of the instrument was demonstrated by synthesis of overlapping 14-mer peptides derived from the sequence of HIV reversed transcriptase. A second mode of operation allows the synthesis to be carried out on the surface of polyethylene pins. Peptides derived from the sequence of human TNF were synthesized using this method and used to characterize antibodies raised against the intact protein.


Subject(s)
Peptides/chemical synthesis , Amino Acid Sequence , Animals , Epitopes/analysis , HIV/enzymology , Humans , Mice , Molecular Sequence Data , Peptide Fragments/chemical synthesis , Peptide Mapping , Peptides/immunology , RNA-Directed DNA Polymerase/chemical synthesis , Robotics/instrumentation , Software , Tumor Necrosis Factor-alpha/chemical synthesis , Tumor Necrosis Factor-alpha/immunology
15.
J Exp Med ; 172(6): 1749-56, 1990 Dec 01.
Article in English | MEDLINE | ID: mdl-2258704

ABSTRACT

Macrophages are a major source of fibrogenic factors that promote healing of injured tissue. The recruitment of fibroblasts to sites of tissue injury is a prerequisite for optimal repair of tissue damage. In the present study, human recombinant tumor necrosis factor alpha (hrTNF-alpha), a major macrophage-derived cytokine, was demonstrated to be a potent fibroblast chemoattractant, inducing migration at picomolar concentrations. Anti-hrTNF-alpha monoclonal antibody neutralized most of the fibroblast chemotactic activity generated during short-term culture of human peripheral blood monocytes stimulated with bacterial lipopolysaccharide, suggesting that TNF-alpha is a major monocyte-derived fibroblast chemoattractant. The portion of the human TNF-alpha molecule responsible for its chemotactic stimulation of fibroblasts appears to reside in residues 31-68. This region is highly conserved between TNF-alpha and lymphotoxin. This peptide is not only itself chemotactic but is also able to block the chemotactic response of fibroblasts to hrTNF-alpha and vice versa, suggesting that they each mediate fibroblast migration through similar mechanisms. These data further underscore the potential importance of TNF-alpha in modulating a variety of fibroblast functions, including chemotaxis and synthesis of collagen, glycosaminoglycans, interleukin 1 alpha (IL-1 alpha) and -beta, human histocompatibility leukocyte antigen A and B antigens, collagenase, prostaglandin E2, and IL-6.


Subject(s)
Chemotaxis/drug effects , Peptide Fragments/chemical synthesis , Peptides/chemical synthesis , Tumor Necrosis Factor-alpha/chemical synthesis , Tumor Necrosis Factor-alpha/pharmacology , Amino Acid Sequence , Antibodies, Monoclonal , Cells, Cultured , Fibroblasts/drug effects , Fibroblasts/physiology , Humans , Infant, Newborn , Kinetics , Lipopolysaccharides/pharmacology , Male , Molecular Sequence Data , Monocytes/drug effects , Monocytes/physiology , Peptide Fragments/pharmacology , Peptides/pharmacology , Recombinant Proteins/pharmacology , Skin Physiological Phenomena , Tumor Necrosis Factor-alpha/immunology
16.
Colomb. med ; 20(4): 142-6, dic. 1989. tab
Article in Spanish | LILACS | ID: lil-83862

ABSTRACT

El factor de necrosis tumoral (FNT) es una citocina producida por los macrofagos activados qeu parece tener importacia tanto en la proteccion como en la patologia de la malaria. En este estudio se evaluo la liberacion espontanea del factor en el sobrenadante de cultivos in vitro de celulas mononucleares de pacientes malaricos. Un grupo de 40 individuos con Plasmodium falciparum o P. vivax y otro de 20 personas normales se estudiaron mediante un bioensayo con fibroblastos murinos de la linea L929 para la determinacion de los niveles de FNT. Casi 50% de los sobrenadantes de los sujetos infectados presentaron altos niveles del factor, con cantidades 5-10 veces mayores que las cifras normales. A pesar de que algunas de estas personas tenian parasitemias altas (5%-9.2%) ninguna hizo cuadros complicados de la enfermedad y no hubo correlacion entre ella y el factor. Tanto al grupo control como al grupo de los infectados se les determinaron niveles de quimica sanguinea y fibrinogeno, sin que se observara ninguna correlacion con los niveles de FNT


Subject(s)
Humans , Male , Female , Malaria/diagnosis , Tumor Necrosis Factor-alpha/therapeutic use , Plasmodium falciparum/isolation & purification , Plasmodium falciparum/microbiology , Tumor Necrosis Factor-alpha/chemical synthesis
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