scholarly journals 1,4-Disubstituted 1,2,3-Triazoles as Amide Bond Surrogates for the Stabilisation of Linear Peptides with Biological Activity

Molecules ◽  
2020 ◽  
Vol 25 (16) ◽  
pp. 3576
Author(s):  
Lisa-Maria Rečnik ◽  
Wolfgang Kandioller ◽  
Thomas L. Mindt
Keyword(s):  
Biological Function ◽  
Structural Diversity ◽  
Biological Properties ◽  
Biologically Active ◽  
Amide Bond ◽  
Peptide Backbone ◽  
Amide Bonds ◽  
Pharmacokinetic Properties ◽  
Endogenous Proteases

Peptides represent an important class of biologically active molecules with high potential for the development of diagnostic and therapeutic agents due to their structural diversity, favourable pharmacokinetic properties, and synthetic availability. However, the widespread use of peptides and conjugates thereof in clinical applications can be hampered by their low stability in vivo due to rapid degradation by endogenous proteases. A promising approach to circumvent this potential limitation includes the substitution of metabolically labile amide bonds in the peptide backbone by stable isosteric amide bond mimetics. In this review, we focus on the incorporation of 1,4-disubstituted 1,2,3-triazoles as amide bond surrogates in linear peptides with the aim to increase their stability without impacting their biological function(s). We highlight the properties of this heterocycle as a trans-amide bond surrogate and summarise approaches for the synthesis of triazole-containing peptidomimetics via the Cu(I)-catalysed azide-alkyne cycloaddition (CuAAC). The impacts of the incorporation of triazoles in the backbone of diverse peptides on their biological properties such as, e.g., blood serum stability and affinity as well as selectivity towards their respective molecular target(s) are discussed.

scholarly journals 1,2,3-Triazoles as Biomimetics in Peptide Science

Molecules ◽  
2021 ◽  
Vol 26 (10) ◽  
pp. 2937
Author(s):  
Naima Agouram ◽  
El Mestafa El Hadrami ◽  
Abdeslem Bentama
Keyword(s):  
Enzymatic Degradation ◽  
Triazole Ring ◽  
Biologically Active ◽  
Amide Bond ◽  
Biologically Relevant ◽  
Amide Bonds ◽  
Natural Peptides ◽  
Mimicking Peptides ◽  
Chemical Mediators

Natural peptides are an important class of chemical mediators, essential for most vital processes. What limits the potential of the use of peptides as drugs is their low bioavailability and enzymatic degradation in vivo. To overcome this limitation, the development of new molecules mimicking peptides is of great importance for the development of new biologically active molecules. Therefore, replacing the amide bond in a peptide with a heterocyclic bioisostere, such as the 1,2,3-triazole ring, can be considered an effective solution for the synthesis of biologically relevant peptidomimetics. These 1,2,3-triazoles may have an interesting biological activity, because they behave as rigid link units, which can mimic the electronic properties of amide bonds and show bioisosteric effects. Additionally, triazole can be used as a linker moiety to link peptides to other functional groups.

scholarly journals Constitutive and Regulated Shedding of Soluble FGF Receptors Releases Biologically Active Inhibitors of FGF-2

2021 ◽  
Vol 22 (5) ◽  
pp. 2712
Author(s):  
Anne Hanneken ◽  
Maluz Mercado ◽  
Pamela Maher
Keyword(s):  
Cell Surface ◽  
Ligand Binding ◽  
Cellular Proliferation ◽  
Biological Activities ◽  
Biological Properties ◽  
Matrix Metalloproteases ◽  
Biologically Active ◽  
Ectodomain Shedding ◽  
High Affinity

The identification of soluble fibroblast growth factor (FGF) receptors in blood and the extracellular matrix has led to the prediction that these proteins modulate the diverse biological activities of the FGF family of ligands in vivo. A recent structural characterization of the soluble FGF receptors revealed that they are primarily generated by proteolytic cleavage of the FGFR-1 ectodomain. Efforts to examine their biological properties are now focused on understanding the functional consequences of FGFR-1 ectodomain shedding and how the shedding event is regulated. We have purified an FGFR-1 ectodomain that is constitutively cleaved from the full-length FGFR-1(IIIc) receptor and released into conditioned media. This shed receptor binds FGF-2; inhibits FGF-2-induced cellular proliferation; and competes with high affinity, cell surface FGF receptors for ligand binding. FGFR-1 ectodomain shedding downregulates the number of high affinity receptors from the cell surface. The shedding mechanism is regulated by ligand binding and by activators of PKC, and the two signaling pathways appear to be independent of each other. Deletions and substitutions at the proposed cleavage site of FGFR-1 do not prevent ectodomain shedding. Broad spectrum inhibitors of matrix metalloproteases decrease FGFR-1 ectodomain shedding, suggesting that the enzyme responsible for constitutive, ligand-activated, and protein kinase C-activated shedding is a matrix metalloprotease. In summary, shedding of the FGFR-1 ectodomain is a highly regulated event, sharing many features with a common system that governs the release of diverse membrane proteins from the cell surface. Most importantly, the FGFR ectodomains are biologically active after shedding and are capable of functioning as inhibitors of FGF-2.

scholarly journals RECENTES AVANÇOS NA FUNCIONALIZAÇÃO SELETIVA DE QUINOLINAS

Química Nova ◽  
2021 ◽  
Author(s):  
Dartagnan Ferreira ◽  
Valter Murie ◽  
Thiago Santos ◽  
Paulo Vieira ◽  
Giuliano Clososki
Keyword(s):  
Wide Spectrum ◽  
Structural Diversity ◽  
Biological Properties ◽  
Biologically Active ◽  
Chemical Transformations ◽  
Heterocyclic Molecules ◽  
Point Of Interest ◽  
Selective Functionalization ◽  
Biological Interest ◽  
Approved Drugs

RECENT ADVANCES IN SELECTIVE FUNCTIONALIZATION OF QUINOLINES. Heterocyclic compounds form an important and extensive group of organic substances. Among nitrogenous heterocyclic molecules, quinolines stand out for exhibiting attractive chemical and biological properties. These substances can be used as ligands, sensors, luminescent and agrochemical materials. In addition, quinoline-containing compounds can exhibit a wide spectrum of pharmacological properties, allowing their use in several approved drugs nowadays. Due to its importance, the synthesis of molecules containing this nucleus becomes a point of interest for synthetic chemists. In this way, several methodologies have been recently developed to prepare quinoline derivatives with high structural diversity. Such chemical transformations allow the chemical modification of these rings with high selectivity and tolerance to diverse functional groups and these properties have been conveniently used in the preparation of biologically active molecules containing this unit. Herein, we present a review of the main methodologies employed in the selective functionalization of quinolines in the last twenty years. In this context, a brief introduction addressing general synthetic and medicinal aspects related to the functionalization positions of the quinoline ring is presented. Several methodologies used in the functionalization of this moiety are discussed, as well relevant synthetic applications, both in the preparation and functionalization of substances of biological interest.

Przeciwnowotworowe działanie składników propolisu. Cz. 1. Ester fenyloetylowy kwasu kawowego (CAPE)

2020 ◽  
Vol 21 (3) ◽  
Author(s):  
Bogdan Kędzia ◽  
Elżbieta Hołderna-Kędzia
Keyword(s):  
Human Colon ◽  
Caffeic Acid Phenethyl Ester ◽  
Biological Properties ◽  
Biologically Active ◽  
Significant Activity ◽  
Colon Adenoma ◽  
Cancer Cell Survival ◽  
Ht 29

The paper presents a review of the publications on the anticancerogenic activity of the biologically active component of propolis – caffeic acid phenethyl ester (CAPE). Literature data indicate numerous biological properties of CAPE, namely: antioxidant, anti-inflammatory, antiviral, immunostimulatory, anti-angiogenic and others. In numerous tests, both in vitro and in vivo, the significant activity of CAPE has been confirmed, including an action against HT-29 human colon adenoma cells, and five: human, murine and other tumor cell cultures. The authors also emphasize that CAPE supports the anticancerogenic effect of drugs, including doxorubicin and cisplatin, due to the reduction of cancer cell survival by 45% and 34%, respectively, compared to the above-mentioned drugs used alone. The conducted research indicates that the induction of apoptosis in cells, i.e. programmed cell death, can be mentioned among the main mechanisms of the anticancerogenic activity of CAPE.

scholarly journals Clitoria ternatea - Shifting Paradigms: From Laboratory to Industry

2021 ◽  
pp. 18-26
Author(s):  
C. B. Ranaweera ◽  
A. K. Chandana
Keyword(s):  
Folk Medicine ◽  
Biological Properties ◽  
Biologically Active ◽  
Potential Health ◽  
Clitoria Ternatea ◽  
In Vivo Experiments ◽  
Industrial Level ◽  
New Treatments

Clitoria ternatea commonly known as Butterfly pea is a standard Ayurvedic medicinal plant used in many parts of south Asian countries. Traditional medicinal plants are a great alternative to find new treatments and for the development of novel antimicrobials to combat many diseases. In Ayurveda and traditional and folk medicine in several countries, decoction and extracts made from C. ternatea are recommended to be used for various medical treatments. C. ternatea extracts claimed to possess antibacterial, antiviral, and antifungal properties, which had been supported and validated by many in vitro and in vivo experiments. However, biologically active compound/s isolation and development novel compounds still remain in its infancy. Despite its enormous potential health benefits, only a single commercial product managed to reach industrial level production. C. ternatea cyclotide studies are also limited despite the fact that it the fastest known natural ligase discovered to date. These cyclotides are rapid peptide ligators and has been the focus of many recent studies on peptide ligation and cyclization for biotechnological applications. In this mini summary we have tried to point out innate unique biological properties of C. ternatea and suggested few future studies, more specifically on C. ternatea cyclotides development against bacterial heat shock proteins (Hsp 100) for novel antimicrobial discovery and development.

scholarly journals Dimeric prion protein ligand activates Adgrg6 but does not rescue myelinopathy of PrP-deficient mice

2020 ◽  
Author(s):  
Anna Henzi ◽  
Assunta Senatore ◽  
Asvin KK Lakkaraju ◽  
Claudia Scheckel ◽  
Jonas Mühle ◽  
...  
Keyword(s):  
Prion Protein ◽  
Biologically Active ◽  
Pharmacokinetic Properties ◽  
Attractive Therapeutic Target ◽  
Sciatic Nerves ◽  
Transcriptomic Changes ◽  
G Protein Coupled ◽  
Peripheral Nervous System Myelin

AbstractThe adhesion G-protein coupled receptor Adgrg6 (formerly Gpr126) is instrumental in the development, maintenance and repair of peripheral nervous system myelin. The prion protein (PrP) is a potent activator of Adgrg6 and could be used as a potential therapeutic agent in treating peripheral demyelinating and dysmyelinating diseases. We designed a dimeric Fc-fusion protein comprising the myelinotrophic domain of PrP (FT2Fc), which activated Adgrg6 in vitro and exhibited favorable pharmacokinetic properties for in vivo treatment of peripheral neuropathies. While chronic FT2Fc treatment elicited specific transcriptomic changes in the sciatic nerves of PrP knockout mice, no amelioration of the peripheral demyelinating neuropathy was detected. Instead, RNA sequencing of sciatic nerves revealed downregulation of cytoskeletal and sarcomere genes, akin to the gene expression changes seen in myopathic skeletal muscle of PrP overexpressing mice. These results call for caution when devising myelinotrophic therapies based on PrP-derived Adgrg6 ligands. While our treatment approach was not successful, Adgrg6 remains an attractive therapeutic target to be addressed in other disease models or by using different biologically active Adgrg6 ligands.Summary blurbA dimeric prion protein ligand activates Adgrg6 but fails to induce pro-myelination signaling upon chronic treatment in a mouse model of peripheral demyelination.

Resazurin Method for Evaluation of Bioactive Compounds from Cranberry Extracts Using the Metabolic Activity of a ΔSOD1 Mutant of Saccharomyces cerevisiae Yeast Under Severe Osmotic Stress

2020 ◽  
Vol 103 (2) ◽  
pp. 422-427
Author(s):  
Agata Święciło ◽  
Kamila Rybczyńska-Tkaczyk
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Growth Parameters ◽  
Raw Materials ◽  
Antioxidant Properties ◽  
Biological Properties ◽  
Biologically Active ◽  
Antioxidant Compounds ◽  
Alcohol Water

Abstract Background: In addition to nutrients, plant raw materials for food production should also contain substances with beneficial biological properties, which unquestionably include antioxidant compounds. Among the numerous methods of determining the antioxidant properties of samples of plant material, biological methods that provide information about not only the in vivo antioxidant potential of samples but also their metabolism and bioavailability are increasingly valued. Objective: The aim of the study was to assess the antioxidant properties of extracts from large cranberry (Vaccinium macrocarpon) obtained from different producers. Methods: Biologically active compounds were extracted from cranberry fruits using water alone and ethyl alcohol–water in proportions of 1+1 and 4+1 (v/v) as solvents. The following were determined in the extracts: content of phenolic compounds and anthocyanins, total antioxidant capacity based on reduction of the ABTS+• [2,20-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid)] radical cation, and antioxidant properties as reflected by the growth of a Saccharomyces cerevisiae Δsod1 mutant in a liquid hypertonic environment. The growth parameters of this Δsod1 mutant, monitored by a method exploiting a color reaction with resazurin, reflected the antioxidant properties of the extracts. Results: The ethanol–water cranberry extracts showed higher content of polyphenols, anthocyanins, and total antioxidants expressed as Trolox equivalent, determined on the basis of ABTS+• reduction. Conclusions: The antioxidant properties determined by the bioassay did not respond strongly to the data obtained in the in vitro chemical and biochemical assays, because they were more closely associated with the batch of fruit than with the type of solvent used to extract phytochemicals.

scholarly journals Improved Tumor-Targeting with Peptidomimetic Analogs of Minigastrin 177Lu-PP-F11N

Cancers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2629
Author(s):  
Nathalie M. Grob ◽  
Roger Schibli ◽  
Martin Béhé ◽  
Thomas L. Mindt
Keyword(s):  
Tumor Targeting ◽  
Amide Bond ◽  
Amide Bonds ◽  
Structural Modifications ◽  
The Past ◽  
Cell Internalization ◽  
Biodistribution Studies ◽  
Metabolic Degradation

The cholecystokinin-2 receptor (CCK2R) is an attractive target in nuclear medicine due to its overexpression by different tumors. Several radiolabeled peptidic ligands targeting the CCK2R have been investigated in the past; however, their low stability against proteases can limit their uptake in tumors and metastases. Substitution of single or multiple amide bonds with metabolically stable 1,4-disubstituted 1,2,3-triazoles as amide bond bioisosteres proved a promising strategy for improving the tumor-targeting properties of a truncated analog of minigastrin. In this study, we applied the previously studied structural modifications to improve the pharmacokinetic and pharmacodynamic properties of PP-F11N, a minigastrin analog currently in clinical trials. Novel minigastrins (NMGs) as analogs of PP-F11N with one or two amide bonds substituted by 1,2,3-triazoles were synthesized, radiolabeled with 177Lu3+, and subjected to full evaluation in vitro (cell internalization, receptor affinity, stability in blood plasma) and in vivo (stability, biodistribution, SPECT/CT imaging). NMGs with triazoles inserted between the amino acids DGlu10-Ala11 and/or Tyr12-Gly13 showed a significantly increased cellular uptake and affinity toward the CCK2R in vitro. Resistance against the metabolic degradation of the NMGs was comparable to those of the clinical candidate PP-F11N. Imaging by SPECT/CT and biodistribution studies demonstrated a higher uptake in CCK2R-positive tumors but also in the CCK2R-positive stomach. The peptidomimetic compounds showed a slow tumor washout and high tumor-to-kidney ratios. The structural modifications led to the identification of analogs with promising properties for progression to clinical applications in the diagnosis and therapy of CCK2R-positive neoplasms.

scholarly journals Soluble dimeric prion protein ligand activates Adgrg6 receptor but does not rescue early signs of demyelination in PrP-deficient mice

PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0242137 ◽  
Author(s):  
Anna Henzi ◽  
Assunta Senatore ◽  
Asvin K. K. Lakkaraju ◽  
Claudia Scheckel ◽  
Jonas Mühle ◽  
...  
Keyword(s):  
Prion Protein ◽  
Biologically Active ◽  
Pharmacokinetic Properties ◽  
Attractive Therapeutic Target ◽  
Sciatic Nerves ◽  
Transcriptomic Changes ◽  
G Protein Coupled ◽  
Peripheral Nervous System Myelin

The adhesion G-protein coupled receptor Adgrg6 (formerly Gpr126) is instrumental in the development, maintenance and repair of peripheral nervous system myelin. The prion protein (PrP) is a potent activator of Adgrg6 and could be used as a potential therapeutic agent in treating peripheral demyelinating and dysmyelinating diseases. We designed a dimeric Fc-fusion protein comprising the myelinotrophic domain of PrP (FT2Fc), which activated Adgrg6 in vitro and exhibited favorable pharmacokinetic properties for in vivo treatment of peripheral neuropathies. While chronic FT2Fc treatment elicited specific transcriptomic changes in the sciatic nerves of PrP knockout mice, no amelioration of the early molecular signs demyelination was detected. Instead, RNA sequencing of sciatic nerves revealed downregulation of cytoskeletal and sarcomere genes, akin to the gene expression changes seen in myopathic skeletal muscle of PrP overexpressing mice. These results call for caution when devising myelinotrophic therapies based on PrP-derived Adgrg6 ligands. While our treatment approach was not successful, Adgrg6 remains an attractive therapeutic target to be addressed in other disease models or by using different biologically active Adgrg6 ligands.

Properties of Bifidobacteria and Their Use for Scientific and Practical Purposes

2021 ◽  
Vol 37 (3) ◽  
pp. 3-10
Author(s):  
L.I. Nikolaeva
Keyword(s):  
Bacterial Infections ◽  
Biological Properties ◽  
Biologically Active ◽  
Recombinant Vaccines ◽  
Scientific Publications ◽  
Wide Range ◽  
Normal Human ◽  
Made In

Bifidobacteria occupy a special place among various representatives of normal human microbiota. A wide range of probiotic preparations has been obtained based on cultivated strains of various bifidobacteria of the intestinal microbiota. A number of scientific publications noted the immunomodulatory, anticarcinogenic, and antiviral properties of bifidobacteria in vitro and in vivo. Recently, progress has been made in the research and application of this group of microorganisms in genetic engineering. It was established that vaccines against viral and bacterial infections and antitumor substances can be developed on the basis of various strains of bifidobacteria. Bifidobacteria can also be used as adjuvants for other vaccines, as well as delivery systems for biologically active substances to tumors. The prospects for the use of bifidobacteria for the development of recombinant vaccines are discussed. bifidobacteria, medical and biological properties, recombinant vaccines, drug delivery, adjuvants, plasmids This work was funded by the Epidemiology and Microbiology National Research Center. The authors are grateful to V. V. Kuprianov for valuable comments on the text of the review.

Sign in / Sign up

Export Citation Format

Share Document