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1.
Chem Biodivers ; : e202400935, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38818650

RESUMO

The study focuses on the anxiolytic potential of chalcone (2E,4E)-1-(2-hydroxyphenyl)-5-phenylpenta-2,4-dien-1-one (CHALCNM) in adult zebrafish. Successfully synthesized in 58% yield, CHALCNM demonstrated no toxicity after 96 h of exposure. In behavioral tests, CHALCNM (40 mg/kg) reduced locomotor activity and promoted less anxious behavior in zebrafish, confirmed by increased permanence in the light zone of the aquarium. Flumazenil reversed its anxiolytic effect, indicating interaction with GABAA receptors. Furthermore, CHALCNM (4 and 20 mg/kg) preserved zebrafish memory in inhibitory avoidance tests. Virtual screening and ADMET profile studies suggest high oral bioavailability, access to the CNS, favored by low topological polarity (TPSA ≤ 75 Ų) and low incidence of hepatotoxicity, standing out as a promising pharmacological agent against the GABAergic system. In molecular coupling, CHALCNM demonstrated superior affinity to diazepam for the GABAA receptor. These results reinforce the therapeutic potential of CHALCNM in the treatment of anxiety, highlighting its possible future clinical application.

2.
Chem Biodivers ; : e202400538, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639566

RESUMO

This is the first study to analyze the anti-inflammatory and antinociceptive effect of withanicandrin, isolated from Datura Ferox leaves, and the possible mechanism of action involved in adult zebrafish (ZFa). To this end, the animals were treated intraperitoneally (i. p.) with withanicandrin (4; 20 and 40 mg/kg; 20 µL) and subjected to locomotor activity and acute toxicity. Nociception tests were also carried out with chemical agents, in addition to tests to evaluate inflammatory processes induced by κ-Carrageenan 1.5 % and a Molecular Docking study. As a result, withanicandrin reduced nociceptive behavior by capsaicin at a dose of 40 mg/kg and by acid saline at doses of 4 and 40 mg/kg, through neuromodulation of TRPV1 channels and ASICs, identified through blocking the antinociceptive effect of withanicandrin by the antagonists capsazepine and naloxone. Furthermore, withanicandrin caused an anti-inflammatory effect through the reduction of abdominal edema, absence of leukocyte infiltrate in the liver tissue and reduction of ROS in thel liver tissue and presented better affinity energy compared to control morphine (TRPV1) and ibuprofen (COX-1 and COX-2).

3.
Chem Biodivers ; : e202400786, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38777789

RESUMO

This study carried out to investigate the anti-inflammatory and antinociceptive effect of tropane alkaloid (EB7) isolated from E. bezerrae. It evaluated the toxicity and possible involvement of ion channels in the antinociceptive effect of EB7, as well as its anti-inflammatory effect in adult zebrafish (Zfa). Docking studies with EB7 and COX-1 and 2 were also performed. The tested doses of EB7 (4, 20 and 40 mg/kg) did not show any toxic effect on Zfa during the 96h of analysis (LD50>40 mg/kg). They did not produce any alteration in the locomotor behavior of the animals. Furthermore, EB7 showed promising pharmacological effects as it prevented the nociceptive behavior induced by hypertonic saline, capsaicin, formalin and acid saline. EB7 had its analgesic effect blocked by amiloride involving the neuromodulation of ASICs in Zfa. In evaluating the anti-inflammatory activity, the edema induced by κ-carrageenan 3.5 % was reduced by the dose of 40 mg/kg of EB7 observed after the fourth hour of analysis, indicating an effect similar to that of ibuprofen. Molecular docking results indicated that EB7 exhibited better affinity energy when compared to ibuprofen control against the two evaluated targets binding at different sites in the cocrystallized COX-1 and 2 inhibitors.

4.
Chem Biodivers ; 21(4): e202400063, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38329295

RESUMO

The xanthone lichenxanthone did not show toxic effects (LC50>1.0 mg/mL). lichenxanthone prevented nociceptive behavior induced by acidic saline, and its analgesic effect was blocked by amiloride, highlighting the involvement of neuromodulation of acid-sensitive ion channels (ASICs). In the analysis of anti-inflammatory activity, concentrations of 0.1 and 0.5 mg/mL of lichenxanthone reduced the edema induced by k-carrageenan 3.5 %, observed from the fourth hour of analysis. This effect was similar to that observed with ibuprofen (positive control). No leukocyte infiltrates were observed in lichenxanthone, suggesting that the compound acts in the acute inflammatory response. The results of the molecular docking study revealed that lichenxanthone exhibited better affinity energy when compared to the ibuprofen control against the two targets evaluated.


Assuntos
Ibuprofeno , Peixe-Zebra , Animais , Simulação de Acoplamento Molecular , Anti-Inflamatórios/farmacologia , Canais Iônicos
5.
J Infect Dis ; 228(6): 723-733, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37279654

RESUMO

The emergence of novel variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) underscores the need to investigate alternative approaches to prevent infection and treat patients with coronavirus disease 2019. Here, we report the preclinical efficacy of NL-CVX1, a de novo decoy that blocks virus entry into cells by binding with nanomolar affinity and high specificity to the receptor-binding domain of the SARS-CoV-2 spike protein. Using a transgenic mouse model of SARS-CoV-2 infection, we showed that a single prophylactic intranasal dose of NL-CVX1 conferred complete protection from severe disease following SARS-CoV-2 infection. Multiple therapeutic administrations of NL-CVX1 also protected mice from succumbing to infection. Finally, we showed that infected mice treated with NL-CVX1 developed both anti-SARS-CoV-2 antibodies and memory T cells and were protected against reinfection a month after treatment. Overall, these observations suggest NL-CVX1 is a promising therapeutic candidate for preventing and treating severe SARS-CoV-2 infections.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Animais , Humanos , Camundongos , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/prevenção & controle , Camundongos Transgênicos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus
6.
Eur J Immunol ; 52(1): 149-160, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34695227

RESUMO

During the COVID-19 pandemic, Portugal has experienced three distinct SARS-CoV-2 infection waves. We previously documented the prevalence of SARS-CoV-2 immunity, measured by specific antibodies, in September 2020, 6 months after the initial moderate wave. Here, we show the seroprevalence changes 6 months later, up to the second week of March 2021, shortly following the third wave, which was one of the most severe in the world, and 2 months following the start of the vaccination campaign. A longitudinal epidemiological study was conducted, with a stratified quota sample of the Portuguese population. Serological testing was performed, including ELISA determination of antibody class and titers. The proportion of seropositives, which was 2.2% in September 2020, rose sharply to 17.3% (95% CI: 15.8-18.8%) in March 2021. Importantly, circulating IgG and IgA antibody levels were very stable 6 months after the initial determination and up to a year after initial infection, indicating long-lasting infection immunity against SARS-CoV-2. Moreover, vaccinated people had higher IgG levels from 3 weeks post-vaccination when compared with previously infected people at the same time post-infection.


Assuntos
Anticorpos Antivirais/imunologia , Teste Sorológico para COVID-19 , COVID-19 , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , SARS-CoV-2/imunologia , Adolescente , Adulto , COVID-19/epidemiologia , COVID-19/imunologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Portugal/epidemiologia , Prevalência , Fatores de Tempo
7.
Opt Express ; 31(11): 18075-18087, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37381526

RESUMO

It is still unclear how well anomalous trichromats discriminate natural colors and whether commercial spectral filters improve performance in these conditions. We show that anomalous trichromats have good color discrimination with colors drawn from natural environments. It is only about 14% poorer, on average, than normal trichromats in our sample of thirteen anomalous trichromats. No measurable effect of the filters on discrimination was found, even after 8 hours of continuous use. Computations of cone and post-receptoral signals show only a modest increase in medium-to-long-wavelength difference signals, which may explain the absent effect of the filters.

8.
J Biol Inorg Chem ; 28(4): 439-450, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37083842

RESUMO

Antimicrobial resistance is an ever-growing global concern to public health with no clear or immediate solution. Silver nanoparticles (AgNPs) have long been proposed as efficient agents to fight the growing number of antibiotic-resistant strains. However, the synthesis of these particles is often linked to high costs and the use of toxic, hazardous chemicals, with environmental and health impact. In this study, we successfully produced AgNPs by green synthesis with the aid of the extract of two brown algae-Cystoseira baccata (CB) and Cystoseira tamariscifolia (CT)-and characterized their physico-chemical properties. The NPs produced in both cases (Ag@CB and Ag@CT) present similar sizes, with mean diameters of around 22 nm. The antioxidant activity of the extracts and the NPs was evaluated, with the extracts showing important antioxidant activity. The bacteriostatic and bactericidal properties of both Ag@CB and Ag@CT were tested and compared with gold NPs produced in the same algae extracts as previously reported. AgNPs demonstrated the strongest bacteriostatic and bactericidal properties, at concentrations as low as 2.16 µg/mL against Pseudomonas aeruginosa and Escherichia coli. Finally, the capacity of these samples to prevent the formation of biofilms characteristic of infections with a poorer outcome was assessed, obtaining similar results. This work points towards an alternative for the treatment of bacterial infections, even biofilm-inducing, with the possibility of minimizing the risk of drug resistance, albeit the necessary caution implied using metallic NPs.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Phaeophyceae , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Antioxidantes/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antibacterianos , Escherichia coli , Biofilmes , Testes de Sensibilidade Microbiana
9.
Mar Drugs ; 21(7)2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37504928

RESUMO

Bacterial and fungal infections are a challenging global problem due to the reported increasing resistance of pathogenic microorganisms to conventional antimicrobials. Nanomaterials are a promising strategy to fight infections caused by multidrug-resistant microbes. In this work, gold (Au@UP) and silver (Ag@UP) nanoparticles were produced for the first time by green synthesis using an aqueous extract of the invasive macroalgae Undaria pinnatifida (UP). The nanoparticles were characterized by a wide range of physicochemical techniques. Au@UP and Ag@UP demonstrated to be spherical and crystalline with an average size of 6.8 ± 1.0 nm and 14.1 ± 2.8 nm, respectively. Carbohydrates and proteins of the UP extract may participate in the synthesis and capping of the nanoparticles. The UP extract, Ag@UP, and Au@UP were assessed for their antimicrobial activity against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Candida albicans, and Candida auris. Ag@UP showed the highest antimicrobial activity with very low MIC and MBC values for all the tested bacteria, and Au@UP demonstrated to be very effective against biofilm-producing bacteria. The antifungal properties of both Ag@UP and Au@UP were remarkable, inhibiting hyphae formation. This study points towards a very promising biomedical exploitation of this invasive brown algae.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Alga Marinha , Undaria , Antibacterianos/farmacologia , Antibacterianos/química , Antioxidantes/farmacologia , Prata/farmacologia , Prata/química , Nanopartículas Metálicas/química , Ouro/química , Anti-Infecciosos/química , Bactérias , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana
10.
Molecules ; 28(16)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37630268

RESUMO

With the increment of the aging population in recent years, neurodegenerative diseases exert a major global disease burden, essentially as a result of the lack of treatments that stop the disease progression. Alzheimer's Disease (AD) is an example of a neurodegenerative disease that affects millions of people globally, with no effective treatment. Natural compounds have emerged as a viable therapy to fill a huge gap in AD management, and in recent years, mostly fueled by the COVID-19 pandemic, RNA-based therapeutics have become a hot topic in the treatment of several diseases. Treatments of AD face significant limitations due to the complex and interconnected pathways that lead to their hallmarks and also due to the necessity to cross the blood-brain barrier. Nanotechnology has contributed to surpassing this bottleneck in the treatment of AD by promoting safe and enhanced drug delivery to the brain. In particular, exosome-like nanoparticles, a hybrid delivery system combining exosomes and liposomes' advantageous features, are demonstrating great potential in the treatment of central nervous system diseases.


Assuntos
Doença de Alzheimer , COVID-19 , Exossomos , Doenças Neurodegenerativas , Humanos , Idoso , Doença de Alzheimer/tratamento farmacológico , Lipossomos , Pandemias , RNA
11.
Molecules ; 27(3)2022 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-35164406

RESUMO

Sesquiterpene lactones (SL), characterized by their high prevalence in the Asteraceae family, are one of the major groups of secondary metabolites found in plants. Researchers from distinct research fields, including pharmacology, medicine, and agriculture, are interested in their biological potential. With new SL discovered in the last years, new biological activities have been tested, different action mechanisms (synergistic and/or antagonistic effects), as well as molecular structure-activity relationships described. The review identifies the main sesquiterpene lactones with interconnections between immune responses and anti-inflammatory actions, within different cellular models as well in in vivo studies. Bioaccessibility and bioavailability, as well as molecular structure-activity relationships are addressed. Additionally, plant metabolic engineering, and the impact of sesquiterpene lactone extraction methodologies are presented, with the perspective of biological activity enhancement. Sesquiterpene lactones derivatives are also addressed. This review summarizes the current knowledge regarding the therapeutic potential of sesquiterpene lactones within immune and inflammatory activities, highlighting trends and opportunities for their pharmaceutical/clinical use.


Assuntos
Anti-Inflamatórios/farmacologia , Agentes de Imunomodulação/farmacologia , Lactonas/farmacologia , Sesquiterpenos/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Asteraceae/química , Descoberta de Drogas , Humanos , Agentes de Imunomodulação/química , Agentes de Imunomodulação/isolamento & purificação , Lactonas/química , Lactonas/isolamento & purificação , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação
12.
Emerg Infect Dis ; 27(11): 2878-2881, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34437830

RESUMO

In September 2020, we tested 13,398 persons in Portugal for antibodies against severe acute respiratory syndrome coronavirus 2 by using a quota sample stratified by age and population density. We found a seroprevalence of 2.2%, 3-4 times larger than the official number of cases at the end of the first wave of the pandemic.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Pandemias , Portugal/epidemiologia , Prevalência , Estudos Soroepidemiológicos
13.
Oncologist ; 26(9): e1619-e1632, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34018280

RESUMO

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-infected patients with cancer show worse outcomes compared with patients without cancer. The humoral immune response (HIR) of patients with cancer against SARS-CoV-2 is not well characterized. To better understand it, we conducted a serological study of hospitalized patients with cancer infected with SARS-CoV-2. MATERIALS AND METHODS: This was a unicentric, retrospective study enrolling adult patients with SARS-CoV-2 admitted to a central hospital from March 15 to June 17, 2020, whose serum samples were quantified for anti-SARS-CoV-2 receptor-binding domain or spike protein IgM, IgG, and IgA antibodies. The aims of the study were to assess the HIR to SARS-CoV-2; correlate it with different cancer types, stages, and treatments; clarify the interplay between the HIR and clinical outcomes of patients with cancer; and compare the HIR of SARS-CoV-2-infected patients with and without cancer. RESULTS: We included 72 SARS-CoV-2-positive subjects (19 with cancer, 53 controls). About 90% of controls revealed a robust serological response. Among patients with cancer, a strong response was verified in 57.9%, with 42.1% showing a persistently weak response. Treatment with chemotherapy within 14 days before positivity was the only factor statistically shown to be associated with persistently weak serological responses among patients with cancer. No significant differences in outcomes were observed between patients with strong and weak responses. All IgG, IgM, IgA, and total Ig antibody titers were significantly lower in patients with cancer compared with those without. CONCLUSION: A significant portion of patients with cancer develop a proper HIR. Recent chemotherapy treatment may be associated with weak serological responses among patients with cancer. Patients with cancer have a weaker SARS-CoV-2 antibody response compared with those without cancer. IMPLICATIONS FOR PRACTICE: These results place the spotlight on patients with cancer, particularly those actively treated with chemotherapy. These patients may potentially be more vulnerable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, so it is important to provide oncologists further theoretical support (with concrete examples and respective mechanistic correlations) for the decision of starting, maintaining, or stopping antineoplastic treatments (particularly chemotherapy) not only on noninfected but also on infected patients with cancer in accordance with cancer type, stage and prognosis, treatment agents, treatment setting, and SARS-CoV-2 infection risks.


Assuntos
COVID-19 , Neoplasias , Anticorpos Antivirais , Humanos , Imunidade Humoral , Imunoglobulina G , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Estudos Retrospectivos , SARS-CoV-2
14.
Eur J Immunol ; 50(12): 2025-2040, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33084029

RESUMO

SARS-CoV-2 has emerged as a human pathogen, causing clinical signs, from fever to pneumonia-COVID-19-but may remain mild or asymptomatic. To understand the continuing spread of the virus, to detect those who are and were infected, and to follow the immune response longitudinally, reliable and robust assays for SARS-CoV-2 detection and immunological monitoring are needed. We quantified IgM, IgG, and IgA antibodies recognizing the SARS-CoV-2 receptor-binding domain (RBD) or the Spike (S) protein over a period of 6 months following COVID-19 onset. We report the detailed setup to monitor the humoral immune response from over 300 COVID-19 hospital patients and healthcare workers, 2500 University staff, and 198 post-COVID-19 volunteers. Anti-SARS-CoV-2 antibody responses follow a classic pattern with a rapid increase within the first three weeks after symptoms. Although titres reduce subsequently, the ability to detect anti-SARS-CoV-2 IgG antibodies remained robust with confirmed neutralization activity for up to 6 months in a large proportion of previously virus-positive screened subjects. Our work provides detailed information for the assays used, facilitating further and longitudinal analysis of protective immunity to SARS-CoV-2. Importantly, it highlights a continued level of circulating neutralising antibodies in most people with confirmed SARS-CoV-2.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , COVID-19/epidemiologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Soroepidemiológicos , Fatores de Tempo
15.
Cell Tissue Res ; 385(3): 497-518, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34050823

RESUMO

The umbilical cord has been proved to be an easy-access, reliable, and useful source of mesenchymal stem cells (MSC) for clinical applications due to its primitive, immunomodulatory, non-immunogenic, secretory and paracrine, migratory, proliferative, and multipotent properties. This set of characteristics has recently attracted great research interest in the fields of nanotechnology and regenerative medicine and cellular therapy. Accumulating evidence supports a pronounced therapeutic potential of MSC in many different pathologies, from hematology to immunology, wound-healing, tissue regeneration, and oncology. Diabetes mellitus, branded the epidemic of the century, is considered a chronic metabolic disorder, representing a major burden for health system sustainability and an important public health challenge to modern societies. The available treatments for type 2 diabetes mellitus (T2DM) still rely mainly on combinations of oral antidiabetic agents with lifestyle and nutritional adjustments. Despite the continuous development of novel and better hypoglycemic drugs, their efficacy is limited in the installment and progression of silent T2DM complications. T2DM comorbidities and mortality rates still make it a serious, common, costly, and long-term manageable disease. Recently, experimental models, preclinical observations, and clinical studies have provided some insights and preliminary promising results using umbilical cord MSCs to treat and manage diabetes. This review focuses on the latest research and applications of human-derived umbilical cord MSC in the treatment and management of T2DM, exploring and systematizing the key effects of both umbilical cord MSC and its factor-rich secretome accordingly with the major complications associated to T2DM.


Assuntos
Diabetes Mellitus Tipo 2/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/metabolismo , Cordão Umbilical/metabolismo , Humanos
16.
Chemistry ; 27(2): 692-704, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-32830362

RESUMO

Drug delivery vectors based on amphiphiles have important features such as versatile physicochemical properties and stimuli-responsiveness. Amino acid-based surfactants are especially promising amphiphiles due to their enhanced biocompatibility compared to conventional surfactants. They can self-organize into micelles, vesicles and complex hierarchical structures, such as fibers, twisted and coiled ribbons, and tubules. In this work, we investigated the self-assembly and drug loading properties of a family of novel anionic double-tailed lysine-derived surfactants, with variable degree of tail length mismatch, designated as mLys10 and 10Lysn, where m and n are the number of carbon atoms in the tails. These surfactants form tubular aggregates with assorted morphologies in water that undergo gelation due to dense entanglement, as evidenced by light and electron microscopy. Lysozyme (LZM), an enzyme with antimicrobial properties, was selected as model protein for loading. After the characterization of the interfacial properties and phase behavior of the amphiphiles, the LZM-loading ability of the tubules was investigated, under varying experimental conditions, to assess the efficiency of the aggregates as pH- and temperature-sensitive nanocarriers. Further, the toxicological profile of the surfactants per se and surfactant/LZM hydrogels was obtained, using human skin fibroblasts (BJ-5ta cell line). Overall, the results show that the tubule-based hydrogels exhibit very interesting properties for the transport and controlled release of molecules of therapeutic interest.


Assuntos
Anti-Infecciosos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/síntese química , Lisina/química , Tensoativos/química , Linhagem Celular , Portadores de Fármacos/administração & dosagem , Humanos , Hidrogéis/administração & dosagem , Hidrogéis/síntese química , Hidrogéis/química , Micelas , Tensoativos/administração & dosagem , Tensoativos/síntese química
17.
Soft Matter ; 17(30): 7099-7110, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34259282

RESUMO

In this work, we explore the ability of newly synthesized threonine-derived surfactants to form robust, versatile and cytocompatible catanionic vesicles when mixed with gemini surfactants, as potential effective nanocarriers for biomolecules. The threonine surfactants consist of single-tailed amphiphiles with carboxylate headgroups and varying alkyl tail length, CnThr, where n is the (even) number of tail C atoms, varying from 8 to 16. After an initial characterization of the micellization behavior of the neat CnThr surfactants (at pH = 7 and 12), the dodecyl derivative, C12Thr, was selected as the optimal surfactant to investigate regions of formation of spontaneous catanionic vesicles. Phase behavior studies and microstructural characterization of mixtures involving both conventional bis-quat n-s-n gemini (where n and s are the tail and spacer number of C atoms) and biocompatible serine-derived gemini surfactants were carried out. Light and electron microscopy, dynamic light scattering and zeta potential measurements show spontaneous vesicles indeed form and exhibit versatile features in terms of average size, morphology, polydispersity, surface charge and pH. The toxicological profile of the neat surfactants and C12Thr/gemini vesicles based on MTT assays with a L929 cell line was also evaluated, showing good levels of in vitro cytocompatibility. Overall, the assortment of developed catanionic vesicles offers very attractive physicochemical and biological features to be explored for delivery purposes.


Assuntos
Serina , Tensoativos , Micelas , Treonina
18.
Int J Med Sci ; 18(3): 582-592, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33437193

RESUMO

Obesity associates with macrophage accumulation in adipose tissue where these infiltrating cells interact with adipocytes and contribute to the systemic chronic metabolic inflammation present in immunometabolic diseases. Tyrosine hydroxylase (TH) and phenylethanolamine N-methyltransferase (PNMT) are two of the main enzymes of catecholamines (CA) synthesis. Adipocytes and macrophages produce, secrete and respond to CA, but the regulation of their synthesis in the interplay between immune and metabolic systems remains unknown. A model of indirect cell coculture with conditioned medium (CM) from RAW 264.7 macrophages with or without LPS-activation and 3T3-L1 adipocytes and preadipocytes was established to study the effect of cellular secretomes on the expression of the above enzymes. During the adipocyte differentiation process, we found a decrease of TH and PNMT expression. The secretome from LPS-activated macrophages downregulated TH and PNMT expression in preadipocytes, but not in mature adipocytes. Mature adipocytes CM induced a decrease of PNMT levels in RAW 264.7 macrophages. Pre and mature adipocytes showed a similar pattern of TH, PNMT and peroxisome proliferator-activated receptor gamma expression after exposure to pro and anti-inflammatory cytokines. We evidenced macrophages and adipocytes coregulate the expression of CA synthesis enzymes through secretome, with non-inflammatory signaling networks possibly being involved. Mediators released by macrophages seem to equally affect CA production by adipocytes, while adipocytes secretome preferentially affect AD production by macrophages. CA synthesis seems to be more determinant in early stages of adipogenic differentiation. Our results suggest that CA are key signaling molecules in the regulation of immune-metabolic crosstalk within the adipose tissue.


Assuntos
Adipócitos/metabolismo , Tecido Adiposo/imunologia , Comunicação Celular/imunologia , Macrófagos/metabolismo , Obesidade/imunologia , Células 3T3-L1 , Adipócitos/imunologia , Adipocinas/metabolismo , Tecido Adiposo/citologia , Tecido Adiposo/metabolismo , Animais , Catecolaminas/biossíntese , Diferenciação Celular/imunologia , Técnicas de Cocultura , Humanos , Lipopolissacarídeos/imunologia , Macrófagos/imunologia , Camundongos , Obesidade/metabolismo , Feniletanolamina N-Metiltransferase/metabolismo , Células RAW 264.7 , Tirosina 3-Mono-Oxigenase/metabolismo
19.
Curr Microbiol ; 78(6): 2345-2354, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33913000

RESUMO

In the Amazon, the leaching from soil left unprotected by deforestation increases the entry of iron, among other elements, in aquatic ecosystems, which can cause cyanobacterial blooms. This study aimed to investigate the physiological response of a strain of Microcystis panniformis to iron variation. The strain was isolated from a reservoir located in the Western Amazon and produces microcystin-LR. After a period of iron deprivation, the cultures were submitted to three conditions: control (223 µgFe.L-1), treatment with 23 µgFe.L-1, and absence of iron. At regular intervals for eight days, the cell density, levels of chlorophyll a and microcystins were determined. On the second and fourth day, transcription of genes responsive to iron limitation was quantified. Starting on the fourth day of the experiment, the different iron concentrations affected growth, and on the eighth day in the iron-free condition cell density was 90% lower than in control. Chlorophyll cell quota in 23 µgFe.L-1 and control presented similar values, while without iron the cells became chlorotic as of the fourth day Toxin concentration in cells grow in 0 µgFe.L-1 in relation to the control. Higher transcription levels of the feo and fut genes were observed in the 0 µgFe.L-1 and 23 µgFe.L-1 treatments, indicating that the cells were activating high-affinity capture systems to reestablish an adequate concentration of intracellular iron. The increasing deforestation in the Jamari River Basin (Amazon region), can contribute to the occurrence of toxic cyanobacterial blooms due to the greater entrance of iron in water bodies.


Assuntos
Microcistinas , Microcystis , Clorofila A , Ecossistema , Ferro , Microcystis/genética
20.
Proc Natl Acad Sci U S A ; 115(47): E11128-E11137, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30385632

RESUMO

Osteosarcoma (OS), the most common primary bone tumor, is highly metastatic with high chemotherapeutic resistance and poor survival rates. Using induced pluripotent stem cells (iPSCs) generated from Li-Fraumeni syndrome (LFS) patients, we investigate an oncogenic role of secreted frizzled-related protein 2 (SFRP2) in p53 mutation-associated OS development. Interestingly, we find that high SFRP2 expression in OS patient samples correlates with poor survival. Systems-level analyses identified that expression of SFRP2 increases during LFS OS development and can induce angiogenesis. Ectopic SFRP2 overexpression in normal osteoblast precursors is sufficient to suppress normal osteoblast differentiation and to promote OS phenotypes through induction of oncogenic molecules such as FOXM1 and CYR61 in a ß-catenin-independent manner. Conversely, inhibition of SFRP2, FOXM1, or CYR61 represses the tumorigenic potential. In summary, these findings demonstrate the oncogenic role of SFRP2 in the development of p53 mutation-associated OS and that inhibition of SFRP2 is a potential therapeutic strategy.


Assuntos
Neoplasias Ósseas/genética , Carcinogênese/genética , Síndrome de Li-Fraumeni/patologia , Proteínas de Membrana/genética , Osteossarcoma/genética , Proteína Supressora de Tumor p53/genética , Animais , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proteína Rica em Cisteína 61/antagonistas & inibidores , Proteína Rica em Cisteína 61/genética , Proteína Forkhead Box M1/antagonistas & inibidores , Proteína Forkhead Box M1/genética , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Síndrome de Li-Fraumeni/genética , Masculino , Proteínas de Membrana/antagonistas & inibidores , Camundongos , Camundongos Nus , Neovascularização Patológica/genética , Osteoblastos/citologia , Osteossarcoma/patologia
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