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1.
Proc Biol Sci ; 291(2018): 20232840, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38471557

ABSTRACT

Scientific knowledge is produced in multiple languages but is predominantly published in English. This practice creates a language barrier to generate and transfer scientific knowledge between communities with diverse linguistic backgrounds, hindering the ability of scholars and communities to address global challenges and achieve diversity and equity in science, technology, engineering and mathematics (STEM). To overcome those barriers, publishers and journals should provide a fair system that supports non-native English speakers and disseminates knowledge across the globe. We surveyed policies of 736 journals in biological sciences to assess their linguistic inclusivity, identify predictors of inclusivity, and propose actions to overcome language barriers in academic publishing. Our assessment revealed a grim landscape where most journals were making minimal efforts to overcome language barriers. The impact factor of journals was negatively associated with adopting a number of inclusive policies whereas ownership by a scientific society tended to have a positive association. Contrary to our expectations, the proportion of both open access articles and editors based in non-English speaking countries did not have a major positive association with the adoption of linguistically inclusive policies. We proposed a set of actions to overcome language barriers in academic publishing, including the renegotiation of power dynamics between publishers and editorial boards.


Subject(s)
Biological Science Disciplines , Publishing , Language , Linguistics
2.
bioRxiv ; 2023 Oct 08.
Article in English | MEDLINE | ID: mdl-37986858

ABSTRACT

Antibodies have proven highly valuable for therapeutic development; however, they are typically poor candidates for applications that require activation of G protein-coupled receptors (GPCRs), the largest collection of targets for clinically approved drugs. Nanobodies (Nbs), the smallest antibody fragments retaining full antigen-binding capacity, have emerged as promising tools for pharmacologic applications, including GPCR modulation. Past work has shown that conjugation of Nbs with ligands can provide GPCR agonists that exhibit improved activity and selectivity compared to their parent ligands. The neurokinin-1 receptor (NK1R), a GPCR targeted for the treatment of pain, is activated by peptide agonists such as Substance P (SP) and neurokinin A (NKA), which induce signaling through multiple pathways (Gs, Gq and ß-arrestin). In this study, we investigated whether conjugating NK1R ligands with Nbs that bind to a separate location on the receptor would provide chimeric compounds with distinctive signaling properties. We employed sortase A-mediated ligation to generate several conjugates consisting of Nbs linked to NK1R ligands. Many of these conjugates exhibited divergent and unexpected signaling properties and transcriptional outputs. For example, some Nb-NKA conjugates showed enhanced receptor binding capacity, high potency partial agonism, prolonged cAMP production, and an increase in transcriptional output associated with Gs signaling; whereas other conjugates were virtually inactive. Nanobody conjugation caused only minor alterations in ligand-induced upstream Gq signaling with unexpected enhancements in transcriptional (downstream) responses. Our findings underscore the potential of nanobody conjugation for providing compounds with advantageous properties such as biased agonism, prolonged duration of action, and enhanced transcriptional responses. These compounds hold promise not only for facilitating fundamental research on GPCR signal transduction mechanisms but also for the development of more potent and enduring therapeutics.

3.
J Med Chem ; 65(8): 6191-6206, 2022 04 28.
Article in English | MEDLINE | ID: mdl-35420805

ABSTRACT

Inherent susceptibility of peptides to enzymatic degradation in the gastrointestinal tract is a key bottleneck in oral peptide drug development. Here, we present a systematic analysis of (i) the gut stability of disulfide-rich peptide scaffolds, orally administered peptide therapeutics, and well-known neuropeptides and (ii) medicinal chemistry strategies to improve peptide gut stability. Among a broad range of studied peptides, cyclotides were the only scaffold class to resist gastrointestinal degradation, even when grafted with non-native sequences. Backbone cyclization, a frequently applied strategy, failed to improve stability in intestinal fluid, but several site-specific alterations proved efficient. This work furthermore highlights the importance of standardized gut stability test conditions and suggests defined protocols to facilitate cross-study comparison. Together, our results provide a comparative overview and framework for the chemical engineering of gut-stable peptides, which should be valuable for the development of orally administered peptide therapeutics and molecular probes targeting receptors within the gastrointestinal tract.


Subject(s)
Cyclotides , Amino Acid Sequence , Cyclization , Cyclotides/chemistry
4.
Int J Biol Macromol ; 164: 687-693, 2020 Dec 01.
Article in English | MEDLINE | ID: mdl-32663559

ABSTRACT

NTPDases (EC 3.6.1.5) are enzymes belonging to a protein family which have as a common feature the ability to hydrolyze di- and triphosphate nucleotides (ADP and ATP) to monophosphate nucleosides (AMP) in the presence of Ca+2 and Mg+. The potato apyrase has been the first protein of the NTPDase family to be purified. In mammals, these enzymes are involved in physiologic and sick processes as thromboregulation, inflammatory and immunologic responses. In this study, we investigated the in vitro potential of synthetic chalcones on the inhibition of potato apyrase purified from Solanum tuberosum. The protein was purified with high grade purity and its identity was confirmed by electrophoresis, western blot, and LC-MS/MS. Five out of the eight chemically synthetized chalcones analyzed in this study showed significant inhibition of the apyrase activity. The compound with the best rate of inhibition of ATP hydrolytic activity was able to promote 54% inhibition with a concentration of 3.125 µM. Ticlopidine, used as an inhibition drug control, was able to promote inhibitions around 50% of the activity (IC50 = 2.167 µM). Our results with the potato apyrase inhibition with the synthetic chalcones suggest that these compounds may use as potential lead candidates for the treatment of some diseases associated with nucleotides.


Subject(s)
Adenosine Triphosphate/chemistry , Apyrase/antagonists & inhibitors , Chalcones/chemistry , Adenosine Triphosphate/genetics , Amino Acid Sequence/genetics , Antigens, CD/chemistry , Antigens, CD/genetics , Apyrase/chemistry , Apyrase/genetics , Biotechnology , Chalcones/pharmacology , Chromatography, Liquid , Humans , Hydrolysis/drug effects , Protein Engineering , Solanum tuberosum/enzymology , Tandem Mass Spectrometry
5.
Rev Soc Bras Med Trop ; 52: e20180139, 2019 Mar 28.
Article in English | MEDLINE | ID: mdl-30942255

ABSTRACT

INTRODUCTION: High percentages of structural identity and cross-immunoreactivity have been reported between potato apyrase and Schistosoma mansoni ATP diphosphohydrolase (SmATPDases) isoforms, showing the existence of particular epitopes shared between these proteins. METHODS: Potato apyrase was employed using ELISA, western blot, and mouse immunization methods to verify IgE reactivity. RESULTS: Most of the schistosomiasis patient's (75%) serum was seropositive for potato apyrase and this protein was recognized using western blotting, suggesting that parasite and plant proteins share IgE-binding epitopes. C57BL/6 mice immunized with potato apyrase showed increased IgE antibody production. CONCLUSIONS: Potato apyrase and SmATPDases have IgE-binding epitopes.


Subject(s)
Antibodies, Helminth/immunology , Apyrase/immunology , Epitopes/immunology , Immunoglobulin E/immunology , Schistosoma mansoni/immunology , Schistosomiasis mansoni/immunology , Solanum tuberosum/enzymology , Animals , Blotting, Western , Cross Reactions , Enzyme-Linked Immunosorbent Assay , Female , Mice, Inbred C57BL
6.
Exp Parasitol ; 200: 1-6, 2019 May.
Article in English | MEDLINE | ID: mdl-30904692

ABSTRACT

Nucleoside triphosphate diphosphohydrolase (NTPDase) 1 from intracellular amastigotes of Leishmania infantum-infected macrophage was identified by immunocytochemistry and confocal laser scanning microscopy using antibodies that specifically recognize its B-domain. This enzyme was previously characterized in Leishmania promastigote form, and here it is shown to be susceptible to pentamidine isethionate (PEN). In initial assays, this antileishmanial compound (100 µM) reduced 60% phosphohydrolytic activity of promastigotes preparation. An active NTPDase 1 was then isolated by non-denaturing gel electrophoresis, and PEN (10 µM) inhibited 74% and 35% of the ATPase and ADPase activities, respectively, of this pure protein. In addition, PEN 0.1-1 µM inhibited 56% potato apyrase activity, a plant protein that shares high identity with Leishmania NTPDase 1. In contrast, amphotericin B, fluconazole, ketoconazole or allopurinol did not significantly affect phosphohydrolytic activity of either promastigotes preparation or potato apyrase. This work suggests amastigote NTPDase 1 as a new molecular target, and inhibition of its catalytic activity by pentamidine can be part of the mode of action of this drug contributing with the knowledge of its antileishmanial effect.


Subject(s)
Antiprotozoal Agents/pharmacology , Apyrase/antagonists & inhibitors , Leishmania infantum/drug effects , Leishmania infantum/enzymology , Pentamidine/pharmacology , Animals , Antigens, CD , Immunohistochemistry , Macrophages/parasitology , Male , Mice , Mice, Inbred BALB C , Microscopy, Confocal
7.
Rev. Soc. Bras. Med. Trop ; 52: e20180139, 2019. graf
Article in English | LILACS | ID: biblio-1041506

ABSTRACT

Abstract INTRODUCTION: High percentages of structural identity and cross-immunoreactivity have been reported between potato apyrase and Schistosoma mansoni ATP diphosphohydrolase (SmATPDases) isoforms, showing the existence of particular epitopes shared between these proteins. METHODS: Potato apyrase was employed using ELISA, western blot, and mouse immunization methods to verify IgE reactivity. RESULTS: Most of the schistosomiasis patient's (75%) serum was seropositive for potato apyrase and this protein was recognized using western blotting, suggesting that parasite and plant proteins share IgE-binding epitopes. C57BL/6 mice immunized with potato apyrase showed increased IgE antibody production. CONCLUSIONS: Potato apyrase and SmATPDases have IgE-binding epitopes.


Subject(s)
Animals , Female , Apyrase/immunology , Schistosoma mansoni/immunology , Schistosomiasis mansoni/immunology , Solanum tuberosum/enzymology , Immunoglobulin E/immunology , Antibodies, Helminth/immunology , Epitopes/immunology , Enzyme-Linked Immunosorbent Assay , Blotting, Western , Cross Reactions , Mice, Inbred C57BL
8.
Parasitol Int ; 62(1): 44-52, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22995148

ABSTRACT

We identified a shared B domain within nucleoside triphosphate diphosphohydrolases (NTPDases) of plants and parasites. Now, an NTPDase activity not affected by inhibitors of adenylate kinase and ATPases was detected in Leishmania infantum promastigotes. By non-denaturing gel electrophoresis of detergent-homogenized promastigote preparation, an active band hydrolyzing nucleosides di- and triphosphate was visualized and, following SDS-PAGE and silver staining was identified as a single polypeptide of 50kDa. By Western blots, it was recognized by immune sera raised against potato apyrase (SA), r-pot B domain (SB), a recombinant polypeptide derived from the potato apyrase, and LbB1LJ (SC) or LbB2LJ (SD), synthetic peptides derived from the Leishmania NTPDase 1, and by serum samples from dogs with visceral leishmaniasis, identifying the antigenic L. infantum NTPDase 1 and, also, its conserved B domain (r83-122). By immunoprecipitation assays and Western blots, immune sera SA and SB identified the catalytically active NTPDase 1 in promastigote preparation. In addition, the immune sera SB (44%) and SC or SD (87-99%) inhibited its activity, suggesting a direct effect on the B domain. By ELISA, 37%, 45% or 50% of 38 infected dogs were seropositive for r-pot B domain, LbB1LJ and LbB2LJ, respectively, confirming the B domain antigenicity.


Subject(s)
Antigens, CD/chemistry , Antigens, CD/immunology , Antigens, Protozoan/metabolism , Apyrase/chemistry , Apyrase/immunology , Leishmania infantum/enzymology , Leishmania infantum/immunology , Amino Acid Sequence , Animals , Antigens, CD/isolation & purification , Antigens, CD/metabolism , Antigens, Protozoan/chemistry , Antigens, Protozoan/immunology , Apyrase/isolation & purification , Apyrase/metabolism , Dogs , Leishmania infantum/genetics , Models, Molecular , Molecular Sequence Data , Protein Structure, Tertiary , Sequence Alignment
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