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1.
Pharmaceuticals (Basel) ; 17(4)2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38675446

RESUMO

Diabetes mellitus (DM) complications are a burden to health care systems due to the associated consequences of poor glycemic control and the side effects of insulin therapy. Recently. adjuvant therapies, such as vanadium compounds, have gained attention due to their potential to improve glucose homeostasis in patients with diabetes. In order to determine the anti-diabetic and antioxidant effects of the oxidovanadium(IV) complex (Et3NH)2[{VO(OH}2)(ox)2(µ-ox)] or Vox2), rats with streptozotocin (STZ)-induced diabetes were treated with 30 and 100 mg/kg of Vox2, orally administered for 12 days. Vox2 at 100 mg/kg in association with insulin caused a 3.4 times decrease in blood glucose in STZ rats (424 mg/dL), reaching concentrations similar to those in the normoglycemic animals (126 mg/dL). Compared to insulin alone, the association with Vox2 caused an additional decrease in blood glucose of 39% and 65% at 30 and 100 mg/kg, respectively, and an increased pancreatic GSH levels 2.5 times. Vox2 alone did not cause gastrointestinal discomfort, diarrhea, and hepatic or renal toxicity and was not associated with changes in blood glucose level, lipid profile, or kidney or liver function. Our results highlight the potential of Vox2 in association with insulin in treating diabetes.

2.
Bioorg Chem ; 146: 107283, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38513324

RESUMO

The breast cancer resistance protein (BCRP/ABCG2) transporter mediates the efflux of numerous antineoplastic drugs, playing a central role in multidrug resistance related to cancer. The absence of successful clinical trials using specific ABCG2 inhibitors reveals the urge to identify new compounds to attend this critical demand. In this work, a series of 13 magnolol derivatives was tested as ABCG2 inhibitors. Only two compounds, derivatives 10 and 11, showed partial and complete ABCG2 inhibitory effect, respectively. This inhibition was selective toward ABCG2, since none of the 13 compounds inhibited neither P-glycoprotein nor MRP1. Both inhibitors (10 and 11) were not transported by ABCG2 and demonstrated a low cytotoxic profile even at high concentrations (up to 100 µM). 11 emerged as the most promising compound of the series, considering the ratio between cytotoxicity (IG50) and ABCG2 inhibition potency (IC50), showing a therapeutic ratio (TR) higher than observed for 10 (10.5 versus 1.6, respectively). This derivative showed a substrate-independent and a mixed type of inhibition. The effect of compound 11 on the ABCG2 ATPase activity and thermostability revealed allosteric protein changes. This compound did not affect the expression levels of ABCG2 and increased the binding of the conformational-sensitive antibody 5D3. A docking study showed that 11 did not share the same binding site with ABCG2 substrate mitoxantrone. Finally, 11 could revert the chemoresistance to SN-38 mediated by ABCG2.


Assuntos
Antineoplásicos , Compostos de Bifenilo , Neoplasias da Mama , Lignanas , Humanos , Feminino , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Resistencia a Medicamentos Antineoplásicos , Proteínas de Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/metabolismo
3.
Int J Biochem Mol Biol ; 14(4): 51-61, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37736389

RESUMO

Type 1 diabetes mellitus (T1DM), associated with autoimmune destruction of pancreatic ß cells, is observed in children and adolescents. OBJECTIVE: We investigated the potential association of the apolipoprotein M (APOM) polymorphisms rs707921, rs805264, rs805296, rs805297, and rs9404941 in childhood-onset T1DM (n = 144) and compared them to those in healthy (mostly Euro-Brazilian) children (n = 168). METHODS: This project was approved by the Ethics Committee of the Federal University of Parana (CAAE 24676613.6.0000.0102). Genotyping was performed using PCR-restriction fragment length polymorphisms (rs805296 and rs9404941) and TaqMan probes (rs707921, rs805264, and rs805297). RESULTS: All polymorphisms were in Hardy-Weinberg equilibrium. In the codominant model, no significant differences (P > 0.05) were observed in genotype and allele frequencies between healthy controls and children with T1DM. The minor allele frequencies (95% CI) for healthy subjects were rs707921 (A, 10.7%; 7-14%), rs805264 (A, 6.5%; 4-9%), rs805296 (C, 3.6%; 2-6%), rs805297 (A, 22.6%; 22-31%), and rs9404941 (C, 2.7%; 1-4%). The frequencies of the rs805297 A allele and rs805296 C allele were similar to those of other Caucasian populations; both the rs707921 and rs805264 A alleles were similar to American and Latin American populations, whereas that of the rs9404941 C allele was lower than that observed in the Caucasian and Asian populations. CONCLUSIONS: Haplotype analysis suggests that rs805297-C, rs9404941-T, rs805296-T, rs805264-G, and rs707921-C conferred risk (OR: 4.25; 95% CI: 1.81-10.1) to childhood-onset T1DM in the Euro-Brazilian population.

4.
Pharmaceutics ; 15(4)2023 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-37111745

RESUMO

Inhibition of ABC transporters is a promising approach to overcome multidrug resistance in cancer. Herein, we report the characterization of a potent ABCG2 inhibitor, namely, chromone 4a (C4a). Molecular docking and in vitro assays using ABCG2 and P-glycoprotein (P-gp) expressing membrane vesicles of insect cells revealed that C4a interacts with both transporters, while showing selectivity toward ABCG2 using cell-based transport assays. C4a inhibited the ABCG2-mediated efflux of different substrates and molecular dynamic simulations demonstrated that C4a binds in the Ko143-binding pocket. Liposomes and extracellular vesicles (EVs) of Giardia intestinalis and human blood were used to successfully bypass the poor water solubility and delivery of C4a as assessed by inhibition of the ABCG2 function. Human blood EVs also promoted delivery of the well-known P-gp inhibitor, elacridar. Here, for the first time, we demonstrated the potential use of plasma circulating EVs for drug delivery of hydrophobic drugs targeting membrane proteins.

5.
J Vis Exp ; (191)2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36715403

RESUMO

This paper describes a novel, simple, and low-cost device to perform in vitro photodynamic therapy (PDT) assays, named the PhotoACT. The device was built using a set of conventional programmable light-emitting diodes (LEDs), a liquid crystal display (LCD) module, and a light sensor connected to a commercial microcontroller board. The box-based structure of the prototype was made with medium-density fiberboards (MDFs). The internal compartment can simultaneously allocate four cell culture multiwell microplates. As a proof of concept, we studied the cytotoxic effect of the photosensitizer (PS) verteporfin against the HeLa cell line in two-dimensional (2D) culture. HeLa cells were treated with increasing concentrations of verteporfin for 24 h. The drug-containing supernatant medium was discarded, the adherent cells were washed with phosphate-buffered saline (PBS), and drug-free medium was added. In this study, the effect of verteporfin on cells was examined either without light exposure or after exposure for 1 h to light using red-green-blue (RGB) values of 255, 255, and 255 (average fluence of 49.1 ± 0.6 J/cm2). After 24 h, the cell viability was assessed by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide (MTT) assay. Experimental results showed that exposure of cells treated with verteporfin to the light from the device enhances the drug's cytotoxic effect via a mechanism mediated by reactive oxygen species (ROS). In addition, the use of the prototype described in this work was validated by comparing the results with a commercial PDT device. Thus, this LED-based photodynamic therapy prototype represents a good alternative for in vitro studies of PDT.


Assuntos
Antineoplásicos , Fotoquimioterapia , Humanos , Verteporfina/farmacologia , Células HeLa , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Técnicas de Cultura de Células
6.
EXCLI J ; 22: 1155-1172, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38204967

RESUMO

A current clinical challenge in cancer is multidrug resistance (MDR) mediated by ABC transporters. Breast cancer resistance protein (BCRP) or ABCG2 transporter is one of the most important ABC transporters implicated in MDR and the use of inhibitors is a promising approach to overcome the resistance in cancer. This study aimed to characterize the molecular mechanism of ABCG2 inhibitors identified by a repurposing drug strategy using antiviral, anti-inflammatory and antiparasitic agents. Lopinavir and ivermectin can be considered as pan-inhibitors of ABC transporters, since both compounds inhibited ABCG2, P-glycoprotein and MRP1. They inhibited ABCG2 activity showing IC50 values of 25.5 and 23.4 µM, respectively. These drugs were highly cytotoxic and not transported by ABCG2. Additionally, these drugs increased the 5D3 antibody binding and did not affect the mRNA and protein expression levels. Cell-based analysis of the type of inhibition suggested a non-competitive inhibition, which was further corroborated by in silico approaches of molecular docking and molecular dynamics simulations. These results showed an overlap of the lopinavir and ivermectin binding sites on ABCG2, mainly interacting with E446 residue. However, the substrate mitoxantrone occupies a different site, binding to the F436 region, closer to the L554/L555 plug. In conclusion, these results revealed the mechanistic basis of lopinavir and ivermectin interaction with ABCG2. See also the Graphical abstract(Fig. 1).

7.
Biometals ; 35(5): 903-919, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35778658

RESUMO

Diabetes mellitus, a complex and heterogeneous disease associated with hyperglycemia, is a leading cause of mortality and reduces life expectancy. Vanadium complexes have been studied for the treatment of diabetes. The effect of complex [VO(bpy)(mal)]·H2O (complex A) was evaluated in a human hepatocarcinoma (HepG2) cell line and in streptozotocin (STZ)-induced diabetic male Wistar rats conditioned in seven groups with different treatments (n = 10 animals per group). Electron paramagnetic resonance and 51V NMR analyses of complex A in high-glucose Dulbecco's Modified Eagle Medium (DMEM) revealed the oxidation and hydrolysis of the oxidovanadium(IV) complex over a period of 24 h at 37 °C to give low-nuclearity vanadates "V1" (H2VO4-), "V2" (H2V2O72-), and "V4" (V4O124-). In HepG2 cells, complex A exhibited low cytotoxic effects at concentrations 2.5 to 7.5 µmol L-1 (IC50 10.53 µmol L-1) and increased glucose uptake (2-NBDG) up to 93%, an effect similar to insulin. In STZ-induced diabetic rats, complex A at 10 and 30 mg kg-1 administered by oral gavage for 12 days did not affect the animals, suggesting low toxicity or metabolic impairment during the experimental period. Compared to insulin treatment alone, complex A (30 mg kg-1) in association with insulin was found to improve glycemia (30.6 ± 6.3 mmol L-1 vs. 21.1 ± 8.6 mmol L-1, respectively; p = 0.002), resulting in approximately 30% additional reduction in glycemia. The insulin-enhancing effect of complex A was associated with low toxicity and was achieved via oral administration, suggesting the potential of complex A as a promising candidate for the adjuvant treatment of diabetes.


Assuntos
Diabetes Mellitus Experimental , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/tratamento farmacológico , Humanos , Hipoglicemiantes/efeitos adversos , Insulina/metabolismo , Insulina/farmacologia , Malatos , Masculino , Ratos , Ratos Wistar , Estreptozocina , Vanadatos/química , Vanádio/química , Vanádio/farmacologia
8.
Eur J Med Chem ; 237: 114346, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35483322

RESUMO

The primary source of failure of cancer therapies is multidrug resistance (MDR), which can be caused by different mechanisms, including the overexpression of ABC transporters in cancer cells. Among the 48 human ABC proteins, the breast cancer resistance protein (BCRP/ABCG2) has been described as a pivotal player in cancer resistance. The use of functional inhibitors and expression modulators is a promising strategy to overcome the MDR caused by ABCG2. Despite the lack of clinical trials using ABCG2 inhibitors, many compounds have already been discovered. This review presents an overview about various ABCG2 inhibitors that have been identified, discussing some chemical aspects and the main experimental methods used to identify and characterize the mechanisms of new inhibitors. In addition, some biological requirements to pursue preclinical tests are described. Finally, we discuss the potential use of ABCG2 inhibitors in cancer stem cells (CSC) for improving the objective response rate and the mechanism of ABCG2 modulators at transcriptional and protein expression levels.


Assuntos
Antineoplásicos , Neoplasias da Mama , Proteínas de Neoplasias , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/química , Antineoplásicos/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos
9.
Chem Biol Interact ; 351: 109718, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34717915

RESUMO

The ABCG2 transporter plays a pivotal role in multidrug resistance, however, no clinical trial using specific ABCG2 inhibitors have been successful. Although ABC transporters actively extrude a wide variety of substrates, photodynamic therapeutic agents with porphyrinic scaffolds are exclusively transported by ABCG2. In this work, we describe for the first time a porphyrin derivative (4B) inhibitor of ABCG2 and capable to overcome multidrug resistance in vitro. The inhibition was time-dependent and 4B was not itself transported by ABCG2. Independently of the substrate, the porphyrin 4B showed an IC50 value of 1.6 µM and a mixed type of inhibition. This compound inhibited the ATPase activity and increased the binding of the conformational-sensitive antibody 5D3. A thermostability assay confirmed allosteric protein changes triggered by the porphyrin. Long-timescale molecular dynamics simulations revealed a different behavior between the ABCG2 porphyrinic substrate pheophorbide a and the porphyrin 4B. Pheophorbide a was able to bind in three different protein sites but 4B showed one binding conformation with a strong ionic interaction with GLU446. The inhibition was selective toward ABCG2, since no inhibition was observed for P-glycoprotein and MRP1. Finally, this compound successfully chemosensitized cells that overexpress ABCG2. These findings reinforce that substrates may be a privileged source of chemical scaffolds for identification of new inhibitors of multidrug resistance-linked ABC transporters.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Adenosina Trifosfatases/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Porfirinas/farmacologia , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/química , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Adenosina Trifosfatases/química , Adenosina Trifosfatases/metabolismo , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Células HEK293 , Humanos , Irinotecano/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Estrutura Molecular , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Porfirinas/química , Porfirinas/metabolismo , Ligação Proteica , Conformação Proteica/efeitos dos fármacos
10.
FEBS Lett ; 596(3): 381-399, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34939198

RESUMO

A promising strategy to overcome multidrug resistance is the use of inhibitors of ABC drug transporters. For this reason, we evaluated the polyoxovanadates (POVs) [V10 O28 ]6- (V10 ), [H6 V14 O38 (PO4 )]5- (V14 ), [V15 O36 Cl]6- (V15 ) and [V18 O42 I]7- (V18 ) as inhibitors of three major multidrug resistance-linked ABC transporters: P-glycoprotein (P-gp), ABCG2 and MRP1. All of the POVs selectively inhibited P-gp. V10 and V18 were the two most promising compounds, with IC50 values of transport inhibition of 25.4 and 22.7 µm, respectively. Both compounds inhibited P-gp ATPase activity, with the same IC50 value of 1.26 µm. V10 and V18 triggered different conformational changes in the P-gp protein with time-dependent inhibition, which was confirmed using the synthesized salt of V10 with rhodamine B, RhoB-V10 . The hydrophilic nature of POVs supports the hypothesis that these compounds target an unusual ligand-binding site, opening new possibilities in the development of potent modulators of ABC transporters.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP
11.
Chem Biol Interact ; 349: 109641, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34534549

RESUMO

Breast cancer (BC) is the most frequently diagnosed female cancer and second leading cause of death. Despite the discovery of many antineoplastic drugs for BC, the current therapy is not totally efficient. In this study, we investigated the potential of repurposing the well-known diabetes type II drug liraglutide to modulate epigenetic modifications in BC cells lines in vitro and in vivo via Ehrlich mice tumors models. The in vitro results revealed a significant reduction on cell viability, migration, DNMT activity and displayed lower levels of global DNA methylation in BC cell lines after liraglutide treatment. The interaction between liraglutide and the DNMT enzymes resulted in a decrease profile of DNA methylation for the CDH1, ESR1 and ADAM33 gene promoter regions and, consequently, increased their gene and protein expression levels. To elucidate the possible interaction between liraglutide and the DNMT1 protein, we performed an in silico study that indicates liraglutide binding in the catalytic cleft via hydrogen bonds and salt bridges with the interdomain contacts and disturbs the overall enzyme conformation. The in vivo study was also able to reveal that liraglutide and the combined treatment of liraglutide and paclitaxel or methotrexate were effective in reducing tumor growth. Moreover, the modulation of CDH1 and ADAM33 mouse gene expression by DNA demethylation suggests a role for liraglutide in DNMT activity in vivo. Altogether, these results indicate that liraglutide may be further analysed as a new adjuvant treatment for BC.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , DNA (Citosina-5-)-Metiltransferase 1/antagonistas & inibidores , Inibidores Enzimáticos/uso terapêutico , Liraglutida/uso terapêutico , Proteínas ADAM/genética , Animais , Antígenos CD/genética , Neoplasias da Mama/patologia , Caderinas/genética , Linhagem Celular Tumoral , Metilação de DNA/efeitos dos fármacos , Receptor alfa de Estrogênio/genética , Feminino , Humanos , Camundongos , Regiões Promotoras Genéticas
12.
ChemMedChem ; 16(17): 2686-2694, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-33844464

RESUMO

Multidrug resistance (MDR) is one of the major factors in the failure of many chemotherapy approaches. In cancer cells, MDR is mainly associated with the expression of ABC transporters such as P-glycoprotein, MRP1 and ABCG2. Despite major efforts to develop new selective and potent inhibitors of ABC drug transporters, no ABCG2-specific inhibitors for clinical use are yet available. Here, we report the evaluation of sixteen tetrahydroquinoline/4,5-dihydroisoxazole derivatives as a new class of ABCG2 inhibitors. The affinity of the five best inhibitors was further investigated by the vanadate-sensitive ATPase assay. Molecular modelling data, proposing a potential binding mode, suggest that they can inhibit the ABCG2 activity by binding on site S1, previously reported as inhibitors binding region, as well targeting site S2, a selective region for substrates, and by specifically interacting with residues Asn436, Gln398, and Leu555. Altogether, this study provided new insights into THQ/4,5-dihydroisoxazole molecular hybrids, generating great potential for the development of novel most potent ABCG2 inhibitors.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Isoxazóis/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Quinolinas/farmacologia , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Feminino , Humanos , Isoxazóis/química , Modelos Moleculares , Estrutura Molecular , Proteínas de Neoplasias/metabolismo , Quinolinas/química , Relação Estrutura-Atividade
13.
Sci Rep ; 11(1): 1788, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33469044

RESUMO

The ATP-binding cassette transporter ABCG2 mediates the efflux of several chemotherapeutic drugs, contributing to the development of multidrug resistance (MDR) in many cancers. The most promising strategy to overcome ABCG2-mediated MDR is the use of specific inhibitors. Despite many efforts, the identification of new potent and specific ABCG2 inhibitors remains urgent. In this study, a structural optimization of indeno[1,2-b]indole was performed and a new generation of 18 compounds was synthesized and tested as ABCG2 inhibitors. Most compounds showed ABCG2 inhibition with IC50 values below 0.5 µM. The ratio between cytotoxicity (IG50) and ABCG2 inhibition potency (IC50) was used to identify the best inhibitors. In addition, it was observed that some indeno[1,2-b]indole derivatives produced complete inhibition, while others only partially inhibited the transport function of ABCG2. All indeno[1,2-b]indole derivatives are not transported by ABCG2, and even the partial inhibitors are able to fully chemosensitize cancer cells overexpressing ABCG2. The high affinity of these indeno[1,2-b]indole derivatives was confirmed by the strong stimulatory effect on ABCG2 ATPase activity. These compounds did not affect the binding of conformation-sensitive antibody 5D3 binding, but stabilized the protein structure, as revealed by the thermostabilization assay. Finally, a docking study showed the indeno[1,2-b]indole derivatives share the same binding site as the substrate estrone-3-sulfate.


Assuntos
Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/antagonistas & inibidores , Neoplasias da Mama/metabolismo , Indóis/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Antineoplásicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Indóis/química , Relação Estrutura-Atividade
14.
Rev. bras. anal. clin ; 52(4): 337-345, 20201230. tab, ilus
Artigo em Português | LILACS | ID: biblio-1223688

RESUMO

Em humanos, o pH sanguíneo é mantido em uma faixa estreita, entre 7,35 e 7,45. Diferentes mecanismos bioquímicos, de forma harmônica, atuam para a manutenção do pH fisiológico. Múltiplos processos patológicos podem promover alterações no pH e nos gases sanguíneos, caracterizando acidose (pH <7,35) ou alcalose (pH >7,45). A ruptura da homeostasia do pH é identificada pela medição do pH, pressão parcial de dióxido de carbono (pCO2), concentração do bicarbonato (HCO3-) e, adicionalmente, com a pressão de oxigênio (pO2) em sangue arterial, processo descrito como gasometria arterial. Este artigo revisa os principais elementos associados a compreensão das alterações e tem como objetivo central apresentar uma abordagem didática e intuitiva para a caracterização destes distúrbios; e também comenta sobre ferramentais digitais destinadas a interpretações das alterações da gasometria arterial que também são abordados, como programas para computadores em ambiente web e aplicativos para telefonia móvel.


In humans, blood pH is kept in a narrow range, between 7.35 to 7.45. Different biochemical mechanisms, in a harmonic way, act to maintain the physiological pH. Multiple pathological processes can promote changes in pH and blood gases, characterizing acidosis (pH <7.35) or alkalosis (pH> 7.45). The rupture of pH homeostasis is identified by measuring pH, partial pressure of carbon dioxide (pCO2), bicarbonate concentration (HCO3 - and, in addition, with the pressure of oxygen (pO2) in arterial blood, a process described as gasometry arterial. This article reviews the main elements associated with the understanding of acid-base changes and aims to present a didactic and intuitive approach to the characterization of these disorders; and also comments on digital tools for the interpretation of alterations in arterial blood gases are also covered, such as programs for computers in a web environment and applications for mobile phone.


Assuntos
Valores de Referência , Desequilíbrio Ácido-Base , Gasometria , Software , Aplicativos Móveis
15.
Arch Biochem Biophys ; 692: 108515, 2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32791141

RESUMO

Apoptosis-inducing factor (AIF) is a flavoprotein and essential partner of the CHCHD4 redox protein during the mitochondrial intermembrane space import machinery. Mammalian AIF has three cysteine residues, which have received little attention. Previous reports have evidenced a redox interaction between AIF and thioredoxin 1 (Trx1), particularly after oxidant conditions. Therefore, we asked whether the cysteine residues of the human AIF could be oxidized. Our data showed that endogenous AIF could be oxidized to disulfide-linked conjugates (DLC). Overexpressed WT AIF in HEK293T cells, as well as recombinant WT AIF, formed DLC. Expression of C256S, C317S or C441S AIF mutants severely inhibited DLC formation in cells exposed to oxidants. In vitro, DLC formation was completely precluded with C256S and C441S AIF mutants and partially inhibited with the C317S mutant. DLC was shown to enhance cellular susceptibility to apoptosis induced by staurosporine, likely by preventing AIF to maintain mitochondrial oxidative phosphorylation. Cells with decreased expression of Trx1 produced more AIF DLC than those with normal Trx1 levels, and in vitro, Trx1 was able to decrease the amount of AIF DLC. Finally, confocal analysis, as well as immunoblotting of mitochondrial fraction, indicated that a fraction of Trx1 is present in mitochondria. Overall, these data provide evidence that all three cysteine residues of AIF can be oxidized to DLC, which can be disrupted by mitochondrial Trx1.


Assuntos
Fator de Indução de Apoptose , Apoptose , Dissulfetos , Substituição de Aminoácidos , Fator de Indução de Apoptose/química , Fator de Indução de Apoptose/genética , Fator de Indução de Apoptose/metabolismo , Cisteína/química , Cisteína/genética , Cisteína/metabolismo , Dissulfetos/química , Dissulfetos/metabolismo , Células HEK293 , Células HeLa , Humanos , Mutação de Sentido Incorreto , Oxirredução , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Estaurosporina/farmacologia
16.
Phytother Res ; 34(10): 2756-2765, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32510696

RESUMO

It is well established that plants from the Brassicaceae family, particularly watercress, have been associated to reduce oxidative DNA damage. Nasturtium officinale R. Br (watercress) contains glucosinolates, with anti-inflammatory action and protective effect on human health against oxidative stress. We aimed to evaluate whether the standardized extract of Nasturtium officinale (SENO) is capable of changing biomarkers of oxidative stress and inflammation in people with physical disabilities. 65 people enrolled this study: as a control group composed by; 15 people with no physical disability assessed once, 25 people with physical disabilities using 750 mg/kg/day of SENO, and 25 people with physical disabilities using 750 mg/kg/day of placebo-control for 5 weeks. Biomarkers of oxidative stress and inflammation were analyzed on day 0 and 36. The results indicated that SENO was associated with decreasing levels of lipid peroxidation, protein carbonyl, catalase, superoxide dismutase, and C-reactive protein. Furthermore, the cytokine kit demonstrated below and out of invertible range, which was impossible to detect the inflammatory process. Despite the cytokine kit was not able to detect the inflammation; these data might provide supportive evidence that SENO, have affected positively people with physical disabilities decreasing their biomarkers of oxidative stress and C-reactive protein. Further studies are required.


Assuntos
Pessoas com Deficiência/psicologia , Inflamação/diagnóstico , Nasturtium/química , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/química , Estudos de Casos e Controles , Método Duplo-Cego , Humanos
17.
J Proteome Res ; 19(1): 92-105, 2020 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-31599156

RESUMO

Azospirillum brasilense is a diazotrophic microorganism capable of associating with roots of important grasses and cereals, promoting plant growth and increasing crop yields. Nitrogen levels and the Ntr regulatory system control the nitrogen metabolism in A. brasilense. This system comprises the nitrogen regulatory proteins GlnD, which is capable of adding uridylyl groups to the PII proteins, GlnB (PII-1) and GlnZ (PII-2), under limiting nitrogen levels. Under such conditions, the histidine kinase NtrB (nitrogen regulatory protein B) cannot interact with GlnB and phosphorylate NtrC (nitrogen regulatory protein C). The phosphorylated form of NtrC acts as a transcriptional activator of genes involved in the metabolism of alternative nitrogen sources. Considering the key role of NtrC in nitrogen metabolism in A. brasilense, in this work we evaluated the proteomic and metabolomic profiles of the wild-type FP2 strain and its mutant ntrC grown under high and low nitrogen. Analysis of the integrated data identifies novel NtrC targets, including proteins involved in the response against oxidative stress (i.e., glutathione S-transferase and hydroperoxide resistance protein), underlining the importance of NtrC to bacterial survival under oxidative stress conditions.


Assuntos
Azospirillum brasilense , Proteômica , Azospirillum brasilense/genética , Azospirillum brasilense/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Nitrogênio/metabolismo , Fixação de Nitrogênio , Proteínas PII Reguladoras de Nitrogênio/genética , Proteínas PII Reguladoras de Nitrogênio/metabolismo
18.
Bol. latinoam. Caribe plantas med. aromát ; 19(5): 495-507, 2020. tab, graf
Artigo em Inglês | MTYCI, LILACS | ID: biblio-1145991

RESUMO

La composición química del aceite esencial obtenido de las ramas de Ocotea paranaensis se estudió por cromatografía de gases/espectrometría de masas (CG/MS). Se identificaron veintisiete compuestos, que comprenden el 94,82% de los componentes totales. El aceite se caracterizó por una concentración relativamente alta de sesquiterpenos (62,96%), sesquiterpenos oxigenados (33,33%) y diterpeno (3,70%). En cuanto a los compuestos principales, se destacaron Z-nerolidol (19,16%), germacreno D (12,92%) y α-bulnesene (8,47%), que correspondieron al 40,55% de las sustancias encontradas. El aceite esencial analizado de Ocotea paranaensis tiene una buena acción reductora de fosfomolibdeno y es moderadamente tóxico para la Artemia salina (LC50 = 147,91 µg/mL). Mostró potencial hemolítico y actividad moderada contra Staphylococcus aureus (concentración inhibitoria mínima MIC = 250 µg/mL) y Pseudomonas aeruginosa (MIC = 500 µg/mL). No se observaron resultados satisfactorios de citotoxicidad en el linaje H460 y HeLa.


The chemical composition of the essential oil obtained from the branches of Ocotea paranaensis was studied by gas chromatography/mass spectrometry (GC/MS). Twenty-seven compounds, comprising 94.82% of the total components, were identified. The oil showed relatively high concentration of sesquiterpenes (62.96%), oxygenated sesquiterpenes (33.33%), and diterpene (3.70%). Regarding the major compounds, Z-nerolidol (19.16%), germacrene D (12.92%) and α-bulnesene (8.47%) could be highlighted, which corresponded to 40.55% of the substances that were found. The essential oil from Ocotea paranaensis has phosphomolybdenum reducing action and is moderately toxic to the Artemia salina (LC50 = 147.91 µg/mL). It showed haemolytic potential and moderate activity against Staphylococcus aureus, (minimum inhibitory concentration MIC = 250 µg/mL) and Pseudomonas aeruginosa (MIC = 500 µg/mL). No satisfactory cytotoxicity results were observed in lineage H460 and HeLa.


Assuntos
Ocotea/química , Anti-Infecciosos , Antineoplásicos , Antioxidantes , Extratos Vegetais , Cromatografia , Medicina Tradicional
19.
Arch. endocrinol. metab. (Online) ; 63(5): 524-530, Sept.-Oct. 2019. graf
Artigo em Inglês | LILACS | ID: biblio-1038503

RESUMO

ABSTRACT Objective The aim of the study is to describe a portable and convenient software to facilitate the diagnostics of gestational (GDM) and pre-gestational diabetes (PGDM). Materials and methods An open source software, d-GDM, was developed in Java. The integrated development environment Android Studio was used as the Android operational system. The software for GDM diagnosis uses the criteria endorsed by the International Association of Diabetes and Pregnancy Study Group, modified by the World Health Organization. Results GDM diagnosis criteria is not simple to follow, therefore, errors or inconsistencies in diagnosis are expected and could delay the appropriate treatment. The d-GDM, was developed to assist GDM diagnosis with precision and consistency diagnostic reports. The open source software can be manipulated conveniently. The operator requires information regarding the gestational period and selects the appropriate glycaemic marker options from the menu. During operation, pressing the button "diagnosticar" on the screen will present the diagnosis and information for the follow up. d-GDM is available in Portuguese or English and can be downloaded from the Google PlayStore. A responsive web version of d-GDM is also available. The usefulness and accuracy of d-GDM was verify by field tests involving 22 subjects and 5 mobile phone brands. The approval regards user-friendliness and efficiency were 95% or higher. The GDM diagnosis were 100% correct, in this pilot test. d-GDM is a user-friendly, free software for diagnosis that was developed for mobile devices. It has the potential to contribute and facilitate the diagnosis of gestational diabetes for healthcare professionals.


Assuntos
Humanos , Feminino , Gravidez , Técnicas de Apoio para a Decisão , Diabetes Gestacional/diagnóstico , Aplicativos Móveis
20.
Arch Endocrinol Metab ; 63(5): 524-530, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31482958

RESUMO

OBJECTIVE: The aim of the study is to describe a portable and convenient software to facilitate the diagnostics of gestational (GDM) and pre-gestational diabetes (PGDM). MATERIALS AND METHODS: An open source software, d-GDM, was developed in Java. The integrated development environment Android Studio was used as the Android operational system. The software for GDM diagnosis uses the criteria endorsed by the International Association of Diabetes and Pregnancy Study Group, modified by the World Health Organization. RESULTS: GDM diagnosis criteria is not simple to follow, therefore, errors or inconsistencies in diagnosis are expected and could delay the appropriate treatment. The d-GDM, was developed to assist GDM diagnosis with precision and consistency diagnostic reports. The open source software can be manipulated conveniently. The operator requires information regarding the gestational period and selects the appropriate glycaemic marker options from the menu. During operation, pressing the button "diagnosticar" on the screen will present the diagnosis and information for the follow up. d-GDM is available in Portuguese or English and can be downloaded from the Google PlayStore. A responsive web version of d-GDM is also available. The usefulness and accuracy of d-GDM was verify by field tests involving 22 subjects and 5 mobile phone brands. The approval regards user-friendliness and efficiency were 95% or higher. The GDM diagnosis were 100% correct, in this pilot test. d-GDM is a user-friendly, free software for diagnosis that was developed for mobile devices. It has the potential to contribute and facilitate the diagnosis of gestational diabetes for healthcare professionals.


Assuntos
Técnicas de Apoio para a Decisão , Diabetes Gestacional/diagnóstico , Aplicativos Móveis , Feminino , Humanos , Gravidez
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