RESUMO
This study investigated crotamine (CTA), a peptide derived from the venom of the South American rattlesnake Crotalus durissus terrificus, known for its exceptional cell penetration potential. The objective was to explore the antibacterial and antifungal activity of CTA, its ability to inhibit efflux pumps and evaluate the effectiveness of its pharmacological combination with antibiotics and antifungals. In microbiological assays, CTA in combination with antibiotics was tested against strains of S. aureus and the inhibition of NorA, Tet(K) and MepA efflux pumps was also evaluated. CTA alone did not present clinically relevant direct antibacterial action, presenting MIC > 209.7 µM against strains S. aureus 1199B, IS-58, K2068. The standard efflux pump inhibitor CCCP showed significant effects in all negative relationships to assay reproducibility. Against the S. aureus 1199B strain, CTA (20.5 µM) associated with norfloxacin diluted 10 × (320.67 µM) showed a potentiating effect, in relation to the control. Against the S. aureus IS-58 strain, the CTA associated with tetracycline did not show a significant combinatorial effect, either with 2304 or 230.4 µM tetracycline. CTA at a concentration of 2.05 µM associated with ciprofloxacin at a concentration of 309.4 µM showed a significant potentiating effect. In association with EtBr, CTA at concentrations of 2.05 and 20.5 µM potentiated the effect in all strains tested, reducing the prevention of NorA, Tet(K) and MepA efflux pumps. In the C. albicans strain, a potentiating effect of fluconazole (334.3 µM) was observed when combined with CTA (2.05 µM). Against the C. tropicalis strain, a significant effect was also observed in the association of fluconazole 334.3 µM, where CTA 2.05 µM considerably reduced fungal growth and decreased the potentiation of fluconazole. Against the C. krusei strain, no significant potentiating effect of fluconazole was obtained by CTA. Our results indicate that CTA in pharmacological combination potentiates the effects of antibiotics and antifungal. This represents a new and promising antimicrobial strategy for treating a wide variety of infections.
Assuntos
Antibacterianos , Antifúngicos , Venenos de Crotalídeos , Crotalus , Testes de Sensibilidade Microbiana , Antifúngicos/farmacologia , Antifúngicos/química , Antibacterianos/farmacologia , Venenos de Crotalídeos/farmacologia , Animais , Staphylococcus aureus/efeitos dos fármacos , Sinergismo Farmacológico , Candida albicans/efeitos dos fármacos , Serpentes PeçonhentasRESUMO
BACKGROUND: Neglected parasitic diseases constitute a broad spectrum of clinical conditions that, in the chronic phase, lack effective therapies for the target population. The utilization of vaccines based on liposomal nanocarrier systems is emerging, thereby enhancing clinical outcomes in various comorbidities. Consequently, this study aims to assess the immunological activity induced by liposomal nanocarriers against neglected parasitic diseases. METHODS: For the review, the Pubmed, Embase, and Lilacs databases were used using the descriptors vaccine, parasite, and liposome. The following inclusion criteria were adopted: in vivo and in vitro experimental articles. As exclusion criteria: book chapters, editorials, literature reviews and duplicate articles found during the database search. RESULTS: A total of 226 articles were identified, from which 34 were selected for review. The primary diseases identified included Babesia bovis, Entamoeba histolytica, Leishmania braziliensis, Leishmania donovani, Leishmania major, Leishmania infantum, Plasmodium falciparum, Plasmodium chabaudi, Plasmodium chabaudi, Plasmodium yoelii, Toxoplasma gondii and Trypanosoma cruzi. An elevation in cytokines such as GM-CSF, MCP-1, INF-γ, TNF-α, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12, and IL-17 was observed in the studies evaluated regarding the parasitic diseases. Furthermore, cytokines such as IL-4, IL-10, and TGF-ß were diminished with the administration of the vaccine systems in those studies. CONCLUSION: Therefore, the administration of liposomal nanovaccine systems can effectively ameliorate the clinical condition of patients by modulating their immunological profile.
RESUMO
OBJECTIVE: One of the techniques that has gained much attention is the in vitro maturation of oocytes for patients who use assisted reproduction techniques. However, its results are still inferior to controlled ovarian stimulation methodologies. Understanding the maturation mechanisms based on analyses can help improve this methodology's results. The work aims to identify the central genes differentially expressed in oocytes after in vitro maturation in the germinal vesicle and metaphase II stages. METHODS: This work is a computational analysis. The entire search will be conducted using the Gene Expression Omnibus (GEO) database. To carry out and obtain the data present in the work, an advanced research search was carried out in the GEO database within the period from January 1, 2013, to January 1, 2023. A total of 27 genomic data were available in the GEO database, of which only two were used. RESULTS: Two datasets were identified on the Gene Expression Omnibus database platform: registration data GSE158802 and GSE95477. From the analysis, we identified five downregulated and thirty-six upregulated genes; the central genes that correlated with the main gene proteins found were CLTA and PANK1. CONCLUSIONS: There was a differential regulation of gene expression. The most central ones are related to energy capture.
RESUMO
This study aimed to evaluate the antibacterial and inhibitory action of NorA, Tet(K), MsrA and MepA efflux pumps in S. aureus strains using the sesquiterpenes named trans-caryophyllene and caryophyllene oxide, both isolated and encapsulated in liposomes. The antibacterial and inhibitory action of these efflux pumps was evaluated through the serial microdilution test in 96-well microplates. Each sesquiterpene and liposome/sesquiterpene was combined with antibiotics and ethidium bromide (EtBr). The antibiotics named norfloxacin, tetracycline and erythromycin were used. The 1199 B, IS-58, RN4220 and K2068 S. aureus strains carrying NorA, Tet(K), MsrA and MepA, respectively, were tested. In the fluorescence measurement test, K2068 S. aureus was incubated with the sesquiterpenes and EtBr, and the fluorescence emission by EtBr was measured. The tested substances did not show direct antibacterial activity, with MIC >1024 µg/mL. Nonetheless, the isolated trans-caryophyllene and caryophyllene oxide reduced the MIC of antibiotics and EtBr, indicating inhibition of NorA, Tet(K) and MsrA. In the fluorescence test, these same sesquiterpenes increased fluorescence emission, indicating inhibition of MepA. Therefore, the sesquiterpenes named trans-caryophyllene and caryophyllene oxide did not show direct antibacterial action; however, in their isolated form, they showed possible inhibitory action on NorA, Tet(K), MsrA and MepA efflux pumps. They may also act in antibiotic potentiation. Further studies are needed to identify the mechanisms involved in antibiotic potentiation and efflux pump inhibitory action.
Assuntos
Lipossomos , Staphylococcus aureus , Staphylococcus aureus/metabolismo , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Sesquiterpenos Policíclicos , Etídio , Proteínas de Bactérias/metabolismo , Proteínas Associadas à Resistência a Múltiplos MedicamentosRESUMO
The aim of this study was to carry out a systematic literature review to investigate the main immune cells responsible for implantation failures. We selected papers from PubMed, Embase and Virtual Health Library databases. Eligible articles included publications between January 1, 2010 and April 24, 2022. Inclusion criteria were: observational and case-control studies; and the exclusion criteria were: review papers, letters to the editor, abstracts, animal studies and case reports. We extracted the following information: day of collection, number of patients, control group, age of patients, type of sample used, immune cells and cytokines. As main findings in our mapping, we found that in peripheral blood, CD3+, CD4+, CD8+, CD16+, CD56+, CD57+, CD69+, CD154+, CD158a+, NKp46 cells were increased and the CD4+, CD45+, Foxp3 and NKp46 markers were reduced. From the endometrial biopsies, there was an increase in CD3+, CD4+, CD5+, CD8+, CD16+, CD25+, CD45+, CD56+, CD57+, CD68+, CD127+ and a reduction in CD45+, CD56+, NKp46 and FoxP3 cells. Cytokines found increased in peripheral blood included IL-6, IL-10, IL-17, INF-γ, TGF-ß, TNF-α; while IL-4, IL-6, IL-10, IL-35, FoxP3, TGF-ß, SOCS3 were reduced. As for the biopsies, there was an increase in IL-2, IL-6, IL-17, IL-22, IL-23, INF-A1, INF-B1, INF-γ, TNF-R and a reduction in IL-6, IL-10, INF-γ, TGFß, TNF-α. We concluded that immune cells can be modulated during pregnancy failure, but further studies are needed to elucidate the modulating effect of the immune system on the endometrium of these patients.
Assuntos
Interleucina-10 , Interleucina-17 , Gravidez , Feminino , Humanos , Interleucina-6 , Fator de Necrose Tumoral alfa , Citometria de Fluxo , Citocinas , Sistema Imunitário , Fatores de Transcrição ForkheadRESUMO
The efflux systems are considered important mechanisms of bacterial resistance due to their ability to extrude various antibiotics. Several naturally occurring compounds, such as sesquiterpenes, have demonstrated antibacterial activity and the ability to inhibit efflux pumps in resistant strains. Therefore, the objective of this research was to analyze the antibacterial and inhibitory activity of the efflux systems NorA, Tet(K), MsrA, and MepA by sesquiterpenes nerolidol, farnesol, and α-bisabolol, used either individually or in liposomal nanoformulation, against multi-resistant Staphylococcus aureus strains. The methodology consisted of in vitro testing of the ability of sesquiterpenes to reduce the Minimum Inhibitory Concentration (MIC) and enhance the action of antibiotics and ethidium bromide (EtBr) in broth microdilution assays. The following strains were used: S. aureus 1199B carrying the NorA efflux pump, resistant to norfloxacin; IS-58 strain carrying Tet(K), resistant to tetracyclines; RN4220 carrying MsrA, conferring resistance to erythromycin. For the EtBr fluorescence measurement test, K2068 carrying MepA was used. It was observed the individual sesquiterpenes exhibited better antibacterial activity as well as efflux pump inhibition. Farnesol showed the lowest MIC of 16.5 µg/mL against the S. aureus RN4220 strain. Isolated nerolidol stood out for reducing the MIC of EtBr to 5 µg/mL in the 1199B strain, yielding better results than the positive control CCCP, indicating strong evidence of NorA inhibition. The liposome formulations did not show promising results, except for liposome/farnesol, which reduced the MIC of EtBr against 1199B and RN4220. Further research is needed to evaluate the mechanisms of action involved in the inhibition of resistance mechanisms by the tested compounds.
Assuntos
Staphylococcus aureus Resistente à Meticilina , Sesquiterpenos , Farneseno Álcool/farmacologia , Staphylococcus aureus/metabolismo , Staphylococcus aureus Resistente à Meticilina/metabolismo , Lipossomos , Proteínas Associadas à Resistência a Múltiplos Medicamentos , Antibacterianos/farmacologia , Sesquiterpenos/farmacologia , Etídio/farmacologia , Testes de Sensibilidade Microbiana , Proteínas de Bactérias/metabolismoRESUMO
BACKGROUND: Chagas disease kills around 10,000 people yearly, primarily in Latin America, where it is prevalent. Current treatment has limited chronic effectiveness, is unsafe, and has substantial side effects. As a result, the use of oxadiazole derivatives and similar heterocyclic compounds as bioisosteres are well known, and they are prospective candidates in the hunt for novel anti-Trypanosoma cruzi chemicals. Recent research has revealed that the cysteine protease cruzain from T. cruzi is a validated target for disease treatment. OBJECTIVE: Thus, using a molecular dynamics simulation, the current study attempted to determine if a significant interaction occurred between the enzyme cruzain and its ligand. RESULTS: Interactions with the catalytic site and other critical locations were observed. Also, the RMSD values suggested that the molecule under research had stable interactions with its target. CONCLUSION: Finally, the findings indicate that the investigated molecule 2b can interfere enzymatic activity of cruzain, indicating that it might be a promising antichagasic drug.
RESUMO
Valencene and nootkatone are aromatic sesquiterpenes with known biological activities, such as antimicrobial, antioxidant, anti-inflammatory, and antitumor. Given the evidence that encapsulation into nanosystems, such as liposomes, could improve the properties of several compounds, the present study aimed to evaluate the activity of these sesquiterpenes in their isolated state or in liposomal formulations against strains of Staphylococcus aureus carrying efflux pumps. The broth microdilution method evaluated the antibiotic-enhancing activity associated with antibiotics and ethidium bromide (EtBr). The minimum inhibitory concentration was assessed in strains of S. aureus 1199B, IS-58, and RN4220, which carry the efflux proteins NorA, Tet(K), and MsrA. In tests with strain 1199B, valencene reduced the MIC of norfloxacin and EtBr by 50%, while the liposomal formulation of this compound did not show a significant effect. Regarding the strain IS-58, valencene, and its nanoformulation reduced norfloxacin MIC by 60.3% and 50%, respectively. In the non-liposomal form, the sesquiterpene reduced the MIC of EtBr by 90%. Against the RN4220 strain, valencene reduced the MIC of the antibiotic and EtBr by 99% and 93.7%, respectively. Nootkatone and its nanoformulation showed significant activity against the 1199B strain, reducing the EtBr MIC by 21.9%. Against the IS-58 strain, isolated nootkatone reduced the EtBr MIC by 20%. The results indicate that valencene and nootkatone potentiate the action of antibiotics and efflux inhibitors in strains carrying NorA, Tet(K), and MsrA proteins, which suggests that these sesquiterpenes act as efflux pump inhibitors in S. aureus. Therefore, further studies are needed to assess the impact of incorporation into liposomes on the activity of these compounds in vivo.
RESUMO
Myracrodruon urundeuva, popularly known as 'aroeira-do-sertão', a large tree, with a tall trunk. Belonging to the Anacardiaceae family, it occurs in the 'caatinga' and dry forests of Brazil, from Ceará to the states of Paraná and Mato Grosso do Sul. The present study aimed to analyse the whitening and antioxidant activities of the aqueous extract of the leaves of Myracrodruon urundeuva (AELMU). Inhibition of the tyrosinase enzyme, as well as its copper chelating capacity and antioxidant effect were evaluated. The AELMU (at 2000 µg/mL) showed excellent inhibitory action (83.76%) on tyrosinase by chelating the copper ion while kojic acid at the same concentration inhibited 97.81%. Moreover, the extract displayed important antioxidant activity (inhibited 76,46% of the 2,2-diphenyl-1-picrylhydrazyl radical - DPPH; 49,59% of thiobarbituric acid reactive substances and 51,07% of the hydroxyl radical). Thus, the extract under study is promising for use in cosmetics, given its multifactorial action.
RESUMO
BACKGROUND: Tumor plasticity processes impact the treatment of different types of cancer; as an effect of this, the bioprospecting of therapies from natural and/or synthetic compounds that can regulate or modulate the immune system has increased considerably. Oxadiazole derivatives are structures that exhibit diverse biological activities. Therefore, this review aimed to evaluate the activity of oxadiazole compounds against tumor cell lines and their possible immune-mediated mechanisms. METHODS: A search in PubMed, Web of Science, and Science Direct databases was carried out on studies published from January 1, 2004, to January 31, 2022, using "oxadiazole" in combination with the other descriptors "cancer" and "macrophage". Only experimental in vitro and in vivo articles were included. A similar search strategy was used in the Derwent Innovation Index database for technology mapping. The search was performed on Drugbank using the descriptor oxadiazole for commercial mapping. RESULTS: 23 oxadiazole studies were included in this review, and some biological activities linked to antitumoral and immunomodulation were listed. Oxadiazole derivatives inhibited tumor cell growth and proliferation, blocked cell cycle, modulated mitochondrial membrane potential, presented immunoregulatory activity by different mechanisms reducing proinflammatory cytokines levels and acted directly as selective inhibitors of the COX enzyme. There was an increase in oxadiazole patent publications in the last 11 years, with emphasis on chemistry, pharmacy and biotechnology applied to microbiology areas. Compounds with 1,2,4-oxadiazole isomer are predominant in patent publications and approved drugs as observed in the technological and commercial mapping. CONCLUSION: Therefore, oxadiazole derivatives are therapeutic molecules that can be considered promising for the development of cancer therapies.
Assuntos
Antineoplásicos , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Agentes de Imunomodulação , Oxidiazóis/farmacologia , Oxidiazóis/uso terapêutico , Oxidiazóis/química , Linhagem Celular Tumoral , Proliferação de Células , Relação Estrutura-Atividade , Estrutura MolecularRESUMO
In folk medicine, Vismia guianensis is used to treat skin diseases and mycoses in the Amazon region. We evaluated the anti-Candida activity of the hydroalcoholic extract from the leaves of Vismia guianensis (EHVG). HPLC-PDA and FIA-ESI-IT-MSn were used to chemically characterize EHVG. The anti-Candida activity was determined in vitro by the minimum inhibitory concentrations (MIC) against Candida glabrata (ATCC-2001); Candida albicans (ATCC-90028, ATCC-14053, and ATCC-SC5314), and C. albicans clinical isolates. EHVG effects on adhesion, growth, and biofilm formation were also determined. Molecular docking was used to predict targets for EHVG compounds. The main compounds identified included anthraquinone, vismione D, kaempferol, quercetin, and vitexin. EHVG was fungicidal against all tested strains. C. albicans ATCC 14053 and C. glabrata ATCC 2001 were the most sensitive strains, as the extract inhibited their virulence factors. In silico analysis indicated that vismione D presented the best antifungal activity, since it was the most effective in inhibiting CaCYP51, and may act as anti-inflammatory and antioxidant agent, according to the online PASS prediction. Overall, the data demonstrate that EHVG has an anti-Candida effect by inhibiting virulence factors of the fungi. This activity may be related to its vismione D content, indicating this compound may represent a new perspective for treating diseases caused by Candida sp.
RESUMO
OBJECTIVE: To investigate the in vitro activity, synergism, cytotoxicity and cellular immunological response, as well as the molecular affinity between amphotericin B (AmB) and crotamine (CTA), derived from Crotalus durissus terrificus venom against Leishmania amazonensis. METHODS: This study performed the inhibition of promastigotes and amastigotes' growth under different concentrations of the drug and pharmacological combinations (AmB + CTA) based on the Berimbaum method (synergism study). The lactate dehydrogenase (LDH) quantification method was used to determine the cytotoxicity of the drug and combinations employing four cell lines (J774, HepG2, VERO, and C2C12). Following, the levels of Tumour Necrose Factor-alpha (TNF-α) and Interleukin-12 (IL-12) cytokines, using enzyme-linked immunosorbent assay (ELISA) and nitrites, as an indirect measure of Nitric Oxide (NO), using the Griess reaction were assessed in the supernatants of infected macrophages. In silico approach (molecular docking and dynamics) and binding affinity (surface plasmon resonance) between the drug and toxin were also investigated. RESULTS: CTA enhanced AmB effect against promastigote and amastigote forms of L. amazonensis, decreased the drug toxicity in different cell lines and induced the production of important Th1-like cytokines and NO by infected macrophages. The pharmacological combination also displayed consistent molecular interactions with low energy of coupling and a concentration-dependent profile. CONCLUSION: Our data suggest that this pharmacological approach is a promising alternative treatment against L. amazonensis infection due to the improved activity (synergistic effect) achieved against the parasites' forms and to the decreased cytotoxic effect.
Assuntos
Antiprotozoários , Venenos de Crotalídeos , Anfotericina B/metabolismo , Anfotericina B/toxicidade , Animais , Antiprotozoários/farmacologia , Venenos de Crotalídeos/química , Crotalus/metabolismo , Citocinas/metabolismo , Simulação de Acoplamento Molecular , Óxido Nítrico/metabolismoRESUMO
Leishmaniasis is a disease that represents a serious global health problem with a potentially fatal outcome in some cases. Leishmania spp. is transmitted by the bite of a sandfly and the disease is endemic in 98 countries. Treatment is carried out with toxic drugs and not consistently effective, so there is a need for new treatments. Oxadiazoles are five-membered heterocyclic compounds, and their antileishmanial activity is well documented in the literature. Specifically, n-cyclohexyl-1,2,4-oxadiazole (2b) was designed to obtain the simplified molecular data line entry system (SMILES). The approach for predicting pharmacokinetic properties used was pkCSM-Pharmacokinetics and ADME/TOX parameters were achieved. SMILES of 2b and Amphotericin B (ANF B) were submitted to the server and the results were compared. The cytotoxic action of 2b on host cells (LLC-MK2) was also evaluated, using MTT salt and antileishmanial activity against Leishmania infantum promastigotes at different concentrations for 24 h. The molecule 2b studied here demonstrated low toxicity in LLC-MK2 cells even at the highest concentration (1000 µM) with cell viability of 69%. Furthermore, it demonstrated anti-L. infantum action with cell viability of 13% at the highest concentration (1000 µM), while (ANF B) (16 µg/mL) demonstrated cell viability of 7%, justifying the need for further studies with n-cyclohexyl-1.2,4-oxadiazole employing experimental models of leishmaniasis.
RESUMO
BACKGROUND: In a scenario of increased pathogens with multidrug resistance phenotypes, it is necessary to seek new pharmacological options. This fact is responsible for an increase in neoplasms and multiresistant parasitic diseases. In turn, snake venom- derived peptides exhibited cytotoxic action on fungal and bacterial strains, possibly presenting activities in resistant tumor cells and parasites. Therefore, the aim of this work is to verify an antitumor and antiparasitic activity of antimicrobial peptides derived from snake venom. METHODS: For this purpose, searches were performed in the Pubmed, Embase and Virtual Health Library databases by combining the descriptors peptides, venom and snake with antitumor/ antiparasitic agent and in silico. The inclusion criteria: in vitro and in vivo experimental articles in addition to in silico studies. The exclusion criteria: articles that were out of scope, review articles, abstracts, and letters to the reader. Data extracted: peptide name, peptide sequence, semi-maximal inhibitory concentration, snake species, tumor lineage or parasitic strain, cytotoxicity, in vitro and in vivo activity. RESULTS: In total 164 articles were found, of which 14 were used. A total of ten peptides with antiproliferative activity on tumor cells were identified. Among the articles, seven peptides addressed the antiparasitic activity. CONCLUSION: In conclusion, snake venom-derived peptides can be considered as potential pharmacological options for parasites and tumors, however more studies are needed to prove their specific activity.
Assuntos
Anti-Infecciosos , Antineoplásicos , Neoplasias , Animais , Anti-Infecciosos/farmacologia , Anti-Infecciosos/uso terapêutico , Peptídeos Antimicrobianos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antiparasitários/farmacologia , Antiparasitários/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Venenos de Serpentes/farmacologia , SerpentesRESUMO
Chagas disease (CD) is a neglected disease, prevalent and endemic in Latin America, but also present in Europe and North America. The main treatment used for this disease is benznidazole, but its efficacy is variable in the chronic phase and presents high toxicity. So, there is a need for the development of new therapeutic agents. The five-membered heterocyclic 1,2,4-oxadiazole ring has received attention for its unique properties and a broad spectrum of biological activities and is therefore a potential candidate for the development of new drugs. Thus, the aim of this study was to evaluate the activity of the N-cyclohexyl-3-(3-methylphenyl)-1,2,4-oxadiazol-5-amine (2) on the evolutionary forms of Trypanosoma cruzi strain Y, as well as its mechanisms of action and in silico theoretical approach. The results by computational method showed an interaction of the 1,2,4-oxadiazole (2) with TcGAPDH, cruzain, and trypanothione reductase, showing good charge distribution and affinity in those three targets. Furthermore, cytotoxicity in LLC-MK2 cells was performed by the MTT method. In the assays with different parasite forms, the tested compound showed similar time-dependent concentration effect. The evaluation of the antiamastigote effect between the two concentrations tested showed a reduction in the number of infected cells and also in the number of amastigotes per infected cell. By flow cytometry, the compound (2) displayed alterations suggestive of necrotic events. Finally, in scanning electron microscopy structural alterations were present, characteristic of necrosisin the epimastigote forms. Overall, the 1,2,4-oxadiazole derivative (2) here evaluated opens perspectives to the development of new antichagasic agents.
Assuntos
Doença de Chagas , Tripanossomicidas , Trypanosoma cruzi , Linhagem Celular , Doença de Chagas/tratamento farmacológico , Humanos , Oxidiazóis/farmacologia , Oxidiazóis/uso terapêutico , Tripanossomicidas/farmacologia , Tripanossomicidas/uso terapêuticoRESUMO
Liposomes, in addition to providing greater efficacy to antibiotics, decrease toxicity and increase selectivity. This work has as main objectives the sensitization of the need to solve bacterial resistance to antibiotics, addressing the potential of antibiotics carried by liposome. In the preparation of the liposomes, the lipids dipalmitoyl phosphatidylcholine (DPPC), dipalmitoyl phosphatidylserine (DPPS), and cholesterol (COL) with > 99% purity were used. The Staphylococcus aureus strains used were SA-1199B, which expresses the NorA gene encoding the NorA efflux protein, which expels hydrophilic fluoroquinolones and other drugs intercalating DNA dyes, and the wild strain SA-1199. The liposomes associated with antibiotics in the wild type of strain SA-1199 and the carrier strain of pump 1199B, had a better representation of growth inhibition than the wild type strain SA-1199. Given the potential for inhibition of efflux pump seen in the results, we highlight the creation of new drugs or alteration of existing drugs. They are not recognized by the efflux pumps and removed from the target cell.
Assuntos
Infecções Estafilocócicas , Staphylococcus aureus , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Humanos , Lipossomos/metabolismo , Testes de Sensibilidade Microbiana , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismoRESUMO
Given the magnitude of the global snakebite crisis, strategies to ensure the quality of antivenom, as well as the availability and sustainability of its supply are under development by several research groups. Recombinant DNA technology has allowed the engineering of monoclonal antibodies and recombinant fragments as alternatives to conventional antivenoms. Besides having higher therapeutic efficacy, with broad neutralization capacity against local and systemic toxicity, novel antivenoms need to be safe and cost-effective. Due to the biological and physical chemical properties of camelid single-domain antibodies, with high volume of distribution to distal tissue, their modular format, and their versatility, their biotechnological application has grown considerably in recent decades. This article presents the most up-to-date developments concerning camelid single-domain-based antibodies against major toxins from snake venoms, the main venomous animals responsible for reported envenoming cases and related human deaths. A brief discussion on the composition, challenges, and perspectives of antivenoms is presented, as well as the road ahead for next-generation antivenoms based on single-domain antibodies.
Assuntos
Anticorpos de Domínio Único/farmacologia , Mordeduras de Serpentes/tratamento farmacológico , Venenos de Serpentes/antagonistas & inibidores , Animais , Camelídeos Americanos , Humanos , Modelos Moleculares , Engenharia de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Anticorpos de Domínio Único/química , Anticorpos de Domínio Único/genética , Mordeduras de Serpentes/imunologia , Distribuição TecidualRESUMO
A total of forty-three compounds were synthesized, including thirty-two new ones. Among those compounds, seventeen were selected and tested on human tumor cell lines: PC-3 (prostate adenocarcinoma), HCT-116 (colorectal tumor), NCIH-460 (lung carcinoma), SKMEL-103 (melanoma) and AGP-01 (gastric tumor). Alkynylated 1,2,4-oxadiazoles 2m, 3g and 3k exhibited antiproliferative activities against NCIH-460 in culture. Alkynylated N-cyclohexyl-1,2,4-oxadiazoles 3a-m and bis-heterocycle glucoglycero-1,2,3-triazole-N-cyclohexyl-1,2,4-oxadiazole derivatives 5a-k and 6-11 were evaluated for their in vitro efficacy towards Mycobacterium tuberculosis (Mtb) H37Ra and H37Rv strains. In general, glycerosugars conjugated to 1,2,4-oxadiazole via a 1,2,3-triazole linkage (5a, 5e, 5j, 5k, and 7) showed in vitro inhibitory activity against Mtb (H37Rv). The largest molecules bis-triazoles 10 and 11, proved inactive against TB. Probably, the absence of the N-cyclohexyl group in compound 8 and 1,2,4-oxadiazole nucleus in compound 9 were responsible for its low activity. Glucoglycero-triazole-oxadiazole derivatives 5e (10 µM) and 7 (23.9 µM) were the most promising antitubercular compounds, showing a better selective index than when tested against RAW 264.7 and HepG2 cells. Vero cell were used to investigate cytotoxicity of compounds 5a, 5h, 5j, 5k, and these compounds showed good cell viability. Further, in silico studies were performed for most active compounds (5e and 7) with potential drug targets, DprE1 and InhA of Mtb to understand possible interactions aided with molecular dynamic simulation (100ns).
Assuntos
Antineoplásicos/farmacologia , Antituberculosos/farmacologia , Carcinoma de Células Escamosas/tratamento farmacológico , Glicoconjugados/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Mycobacterium tuberculosis/efeitos dos fármacos , Oxidiazóis/química , Alcinos/química , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antituberculosos/síntese química , Antituberculosos/química , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Descoberta de Drogas , Glicoconjugados/síntese química , Glicoconjugados/química , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade , Triazóis/químicaRESUMO
The treatment for hepatitis Delta virus (HDV) still consists of Pegylated interferon (PEG-IFN) combined with inhibitors of Hepatitis B virus (HBV) replication. In some patients may be occur a virological response, which means a negative HDV RNA 6 months after stopping treatment. In this study it was conducted an in vitro approach with the aim to mimic possible immunological events that are observed in patients responding to PEG-IFN therapy. Jurkat cells (human T lymphocyte cell line) were employed alone or co-cultured with THP-1 (human monocytic cell line) and stimulated with controls and HBV Surface Antigen (HBsAg), Small-Delta Antigen (SHDAg), and HBsAg + SHDAg combined. Twenty-four hours stimulation with SHDAg and/or HBSAg led to a toxic profile in a co-culture condition and cell supernatants were collected for cytokines quantification. PEG-IFN was added and cells were incubated for additional 24 h. Co-cultured cells incubated with the association (SHDAg + PEG-IFN) significantly produced levels of IFN-γ, IL-2 and IL-12. On the other hand, the HBsAg alone was able to inhibit the production of IFN-γ, suggesting that this antigen may hinder the treatment exclusively with PEG-IFN.
Assuntos
Antivirais/farmacologia , Citocinas/metabolismo , Citotoxicidade Imunológica/efeitos dos fármacos , Hepatite D/tratamento farmacológico , Vírus Delta da Hepatite/imunologia , Interferons/farmacologia , Polietilenoglicóis/farmacologia , Técnicas de Cocultura , Antígenos de Superfície da Hepatite B/farmacologia , Hepatite D/imunologia , Hepatite D/metabolismo , Hepatite D/virologia , Vírus Delta da Hepatite/patogenicidade , Antígenos da Hepatite delta/farmacologia , Interações Hospedeiro-Patógeno , Humanos , Interferon gama/metabolismo , Interleucina-12/metabolismo , Interleucina-2/metabolismo , Células Jurkat , Transdução de Sinais , Células THP-1RESUMO
COVID-19 is an emerging outbreak similar to previous pandemics caused by Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS). Till date, SARS-CoV-2 infection is still spreading, representing a major threat to public health, where several control measures are being practiced in order to culminate its spread. The research and development of new drugs require a lot of funding in addition to being a slow and costly process. As a result, new techniques have been proposed to streamline this process. The repositioning or repurposing of drugs represents an attractive strategy, presenting a promising way to introduce new drugs. Currently, numerous reused drugs are already available in the market and are in practice. In this review, it was observed that the antiviral drugs Entricitabine and Tenofovir display potential therapeutic efficacy in preclinical studies. Therefore, in silico analyses were considered a potential tool for predicting the effectiveness of drugs, mainly as an effective approach to encourage a complementary in vitro and in vivo antiviral evaluation.