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1.
Virol J ; 20(1): 79, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37101205

RESUMO

BACKGROUND: Porcine reproductive and respiratory syndrome virus (PRRSV) is an economically important pathogen, characterized by its genetic and antigenic variation. The PRRSV vaccine is widely used, however, the unsatisfied heterologic protection and the risk of reverse virulence raise the requirement to find some new anti-PRRSV strategies for disease control. Tylvalosin tartrate is used to inhibit PRRSV in the field non-specifically, however, the mechanism is still less known. METHODS: The antiviral effects of Tylvalosin tartrates from three producers were evaluated in a cell inoculation model. Their safety and efficacy concentrations, and effecting stage during PRRSV infection were analyzed. And, the Tylvalosin tartrates regulated genes and pathways which are potentially related to the anti-viral effect were further explored by using transcriptomics analysis. Last, the transcription level of six anti-virus-related DEGs was selected to confirm by qPCR, and the expression level of HMOX1, a reported anti-PRRSV gene, was proved by western blot. RESULTS: The safety concentrations of Tylvalosin tartrates from three different producers were 40 µg/mL (Tyl A, Tyl B, and Tyl C) in MARC-145 cells and 20 µg/mL (Tyl A) or 40 µg/mL (Tyl B and Tyl C) in primary pulmonary alveolar macrophages (PAMs) respectively. Tylvalosin tartrate can inhibit PRRSV proliferation in a dose-dependent manner, causing more than 90% proliferation reduction at 40 µg/mL. But it shows no virucidal effect, and only achieves the antiviral effect via long-term action on the cells during the PRRSV proliferation. Furthermore, GO terms and KEGG pathway analysis was carried out based on the RNA sequencing and transcriptomic data. It was found that the Tylvalosin tartrates can regulate the signal transduction, proteolysis, and oxidation-reduction process, as well as some pathways such as protein digestion and absorption, PI3K-Akt signaling, FoxO signaling, and Ferroptosis pathways, which might relate to PRRSV proliferation or host innate immune response, but further studies still need to confirm it. Among them, six antivirus-related genes HMOX1, ATF3, FTH1, FTL, NR4A1, and CDKN1A were identified to be regulated by Tylvalosin tartrate, and the increased expression level of HMOX1 was further confirmed by western blot. CONCLUSIONS: Tylvalosin tartrate can inhibit PRRSV proliferation in vitro in a dose-dependent manner. The identified DEGs and pathways in transcriptomic data will provide valuable clues for further exploring the host cell restriction factors or anti-PRRSV target.


Assuntos
Síndrome Respiratória e Reprodutiva Suína , Vírus da Síndrome Respiratória e Reprodutiva Suína , Suínos , Animais , Vírus da Síndrome Respiratória e Reprodutiva Suína/genética , Vírus da Síndrome Respiratória e Reprodutiva Suína/metabolismo , Antivirais/farmacologia , Antivirais/metabolismo , Tartaratos/metabolismo , Tartaratos/farmacologia , Transcriptoma , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/farmacologia , Macrófagos Alveolares , Replicação Viral
2.
Chem Biodivers ; 20(7): e202300115, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37236909

RESUMO

Most heavy metals and industrial chemicals such as nicotine and lead cause harm to the reproduction process through a decrease in sperm motility, fertilization process, and sperm binding to the oocyte. Salvia officinalis L. (sage) has been reported to enhance serum testosterone levels and other certain biochemical enzymes. Thus, the current study is aimed at evaluating the potential health benefits of S. officinalis L. methanol extract on lead and nicotine hydrogen tartrate-induced sperm quality degeneration in male rats and also identifying some of the non-polar volatile bioactive compounds that might be attributed to the bioactivity of S. officinalis extract using gas chromatography-mass spectrometry (GC/MS). In the study, fifty-four mature male albino rats of about 220-250 g [were divided randomly and equally into 9 groups (n=6)]. Sperm quality degeneration was induced through the oral administration of 1.5 g/L of lead acetate in drinking water or peritoneal injection of 0.50 mg/kg (animal weight) nicotine hydrogen tartrate for sixty days. Two doses (200 & 400 mg/kg b.w.) of S. officinalis L. were used. The rats were anesthetized after the experimental period and then sacrificed. Blood samples were collected while the epididymis, testicle, and accessory sex organs (prostates and seminal vesical) were taken for histopathological studies. Twelve major compounds were identified through the GC/MS analysis of S. officinalis L. methanol extract. Lead and nicotine toxicity had a great effect on the rats' sperm quality causing a significant (p<0.05) decrease in the quantity of sperm and sperm motility as well as an upsurge in the abnormalities of the sperm and a reduction in the length & diameter of seminiferous tubules and size & weight of sexual organs (accessory sex glands, epididymis, and testis). The administration of S. officinalis L. methanol extract, however, had a positive impact on the sexual organ weights, semen quality & quantity, and rats' fertility, thus, ameliorating the adversative effects of both lead and nicotine. Further evaluation and isolation of the bioactive components are recommended as potential drug leads.


Assuntos
Metanol , Salvia officinalis , Ratos , Masculino , Animais , Nicotina/farmacologia , Análise do Sêmen , Tartaratos/farmacologia , Ratos Wistar , Contagem de Espermatozoides/métodos , Motilidade dos Espermatozoides , Sementes , Espermatozoides , Extratos Vegetais/farmacologia
3.
Ann Bot ; 129(1): 53-64, 2022 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-34582551

RESUMO

BACKGROUND AND AIMS: Soil phosphorus (P) deficiency and salinity are constraints to crop productivity in arid and semiarid regions. Salinity may weaken the effect of P fertilization on plant growth. We investigated the interactive effects of soil P availability and salinity on plant growth, P nutrition and salt tolerance of two alfalfa (Medicago sativa) cultivars. METHODS: A pot experiment was carried out to grow two cultivars of alfalfa in a loess soil under a combination of different rates of added P (0, 40, 80 and 160 mg P kg-1 soil as monopotassium phosphate) and sodium chloride (0, 0.4, 0.8 and 1.6 g NaCl kg-1 soil). Plant biomass, concentrations of P ([P]), sodium ([Na]) and potassium ([K]) were determined, and rhizosheath carboxylates were analysed. KEY RESULTS: There were significant interactions between soil P availability and salinity on some, but not all, of the parameters investigated, and interactions depended on cultivar. Plant growth and P uptake were enhanced by P fertilization, but inhibited by increased levels of salinity. Increasing the salinity resulted in decreased plant P-uptake efficiency and [K]/[Na]. Only soil P availability had a significant effect on the amount of tartrate in the rhizosheath of both cultivars. CONCLUSIONS: Increased salinity aggravated P deficiency. Appropriate application of P fertilizers improved the salt tolerance of alfalfa and increased its productivity in saline soils.


Assuntos
Medicago sativa , Salinidade , Fertilização , Fósforo , Raízes de Plantas , Sódio , Solo , Tartaratos/farmacologia
4.
Int J Mol Sci ; 23(17)2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-36076987

RESUMO

Toxoplasma gondii is a widespread intracellular pathogen that infects humans and a variety of animals. The current therapeutic strategy for human toxoplasmosis is a combination of sulphadiazine and pyrimethamine. However, this combination still has a high failure rate and is ineffective against chronic infections. Therefore, it is important to discover a new anti-T. gondii drug that is safer and more effective in both humans and animals. In this study, we describe the anti-T. gondii activities of the 16-membered macrolide tilmicosin and acetylisovaleryltylosin tartrate (ATLL). Both tilmicosin and ATLL potently inhibited T. gondii with a half-maximal effective concentration (EC50) of 17.96 µM and 10.67 µM, respectively. Interestingly, tilmicosin and ATLL had different effects on the parasites. ATLL exhibited a potent inhibitory effect on intracellular parasite growth, while tilmicosin suppressed parasites extracellularly. By studying the lytic cycle of T. gondii after treatment, we found that ATLL potently inhibited the intracellular proliferation of tachyzoites, while tilmicosin affected the invasion of tachyzoites. Immunofluorescence analysis using ATLL-treated T. gondii showed morphologically abnormal parasites, which may be due to the inhibition of tachyzoite proliferation and division. In addition, tilmicosin and ATLL significantly delayed the death of mice caused by acute toxoplasmosis. Our results suggest that ATLL has potent anti-Toxoplasma activity both in vitro and in vivo and may be an alternative to toxoplasmosis in the future.


Assuntos
Leucemia-Linfoma de Células T do Adulto , Toxoplasma , Toxoplasmose , Animais , Humanos , Camundongos , Tartaratos/farmacologia , Toxoplasmose/tratamento farmacológico , Toxoplasmose/parasitologia , Tilosina/análogos & derivados
5.
BMC Oral Health ; 22(1): 290, 2022 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842599

RESUMO

BACKGROUND: External root resorption is one of common complications of orthodontic treatment, while internal root resorption is rarely observed, and the difference between pulp and periodontal tissues during orthodontic treatment is still unknown. The purpose of this study was to evaluate the effects of orthodontic forces on histological and cellular changes of the dental pulp and periodontal tissues. METHODS: Orthodontic tooth movement model was established in Forty-eight adult male Wistar rats. The distance of orthodontic tooth movement was quantitatively analyzed. The histological changes of pulp and periodontal tissues were performed by hematoxylin-eosin staining, tartrate-resistant acid phosphate staining was used to analyze the changes of osteoclast number, immunohistochemistry analysis and reverse transcription polymerase chain reaction were used to examine the receptor of nuclear factor-κB ligand (RANKL) and osteoprotegerin (OPG) expression. The width of tertiary dentine was quantitatively analyzed. Tartrate-resistant acid phosphate staining and the erosion area of osteo assay surface plate was used to evaluate osteoclast activity. RESULTS: The orthodontic tooth movement distance increased in a force dependent manner, and reached the peak value when orthodontic force is 60 g. Heavy orthodontic force increased the RANKL expression of periodontal ligament srem cells (PDLSCs) which further activated osteoclasts and resulted in external root resorption, while the RANKL expression of dental pulp stem cells (DPSCs) was relatively low to activate osteoclasts and result in internal root resorption, and the dental pulp tend to form tertiary dentine under orthodontic force stimulation. CONCLUSIONS: Heavy orthodontic forces activated osteoclasts and triggered external root resorption by upregulating RANKL expression in rat periodontal tissues, while there was no significant change of RANKL expression in dental pulp tissue under heavy orthodontic forces, which prevented osteoclast activation and internal root resorption.


Assuntos
Osteoprotegerina/metabolismo , Ligante RANK/metabolismo , Reabsorção da Raiz , Animais , Masculino , Osteoclastos , Ligamento Periodontal/metabolismo , Fosfatos , Ratos , Ratos Wistar , Reabsorção da Raiz/etiologia , Tartaratos/farmacologia , Técnicas de Movimentação Dentária/efeitos adversos
6.
Mol Pharm ; 18(9): 3326-3341, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34428047

RESUMO

Orally dosed drugs must dissolve in the gastrointestinal (GI) tract before being absorbed through the epithelial cell membrane. In vivo drug dissolution depends on the GI tract's physiological conditions such as pH, residence time, luminal buffers, intestinal motility, and transit and drug properties under fed and fasting conditions (Paixão, P. et al. Mol. Pharm.2018 and Bermejo, et al. M. Mol. Pharm.2018). The dissolution of an ionizable drug may benefit from manipulating in vivo variables such as the environmental pH using pH-modifying agents incorporated into the dosage form. A successful example is the use of such agents for dissolution enhancement of BCS class IIb (high-permeability, low-solubility, and weak base) drugs under high gastric pH due to the disease conditions or by co-administration of acid-reducing agents (i.e., proton pump inhibitors, H2-antagonists, and antacids). This study provides a rational approach for selecting pH modifiers to improve monobasic and dibasic drug compounds' dissolution rate and extent under high-gastric pH dissolution conditions, since the oral absorption of BCS class II drugs can be limited by either the solubility or the dissolution rate depending on the initial dose number. Betaine chloride, fumaric acid, and tartaric acid are examples of promising pH modifiers that can be included in oral dosage forms to enhance the rate and extent of monobasic and dibasic drug formulations. However, selection of a suitable pH modifier is dependent on the drug properties (e.g., solubility and pKa) and its interplay with the pH modifier pKa or pKas. As an example of this complex interaction, for basic drugs with high pKa and intrinsic solubility values and large doses, a polyprotic pH modifier can be expected to outperform a monoacid pH modifier. We have developed a hierarchical mass transport model to predict drug dissolution of formulations under varying pH conditions including high gastric pH. This model considers the effect of physical and chemical properties of the drug and pH modifiers such as pKa, solubility, and particle size distribution. This model also considers the impact of physiological conditions such as stomach emptying rate, stomach acid and buffer secretion, residence time in the GI tract, and aqueous luminal volume on drug dissolution. The predictions from this model are directly applicable to in vitro multi-compartment dissolution vessels and are validated by in vitro experiments in the gastrointestinal simulator. This model's predictions can serve as a potential data source to predict plasma concentrations for formulations containing pH modifiers administered under the high-gastric pH conditions. This analysis provides an improved formulation design procedure using pH modifiers by minimizing the experimental iterations under both in vitro and in vivo conditions.


Assuntos
Excipientes/farmacologia , Absorção Gastrointestinal/efeitos dos fármacos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Modelos Biológicos , Administração Oral , Betaína/farmacologia , Disponibilidade Biológica , Química Farmacêutica , Simulação por Computador , Desenho de Fármacos , Liberação Controlada de Fármacos , Fumaratos/farmacologia , Humanos , Solubilidade , Tartaratos/farmacologia
7.
Ecotoxicol Environ Saf ; 187: 109790, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31639642

RESUMO

We studied the effects of three organic acids (citric acid, tartaric acid and malic acid) on the biomass, photosynthetic pigment content and photosynthetic parameters of Salix variegata under Cd stress and observed the ultrastructure of mesophyll cells in each treatment. Cd stress significantly reduced photosynthesis by reducing the content of pigments and disrupting chloroplast structure, which consequently decreased the biomass. However, respective addition of three organic acids greatly increased the biomass of S. variegata under Cd stress. Among them, the effect of malic acid or tartaric acid on shoot and total biomass accumulation was greater than that of citric acid. The alleviation of biomass probably related with the photosynthetic process. Results revealed that treatment with each organic acid enhanced the net photosynthesis rate under Cd stress. Malic acid promoted plant growth and biomass by increasing the chlorophyll content and mitigating damage to the photosynthetic apparatus resulting from Cd stress. Tartaric acid had little impact on the photosynthetic pigment content, but it was important in mitigating the ultrastructural damage of plants caused by Cd. Addition of citric acid significantly increased the carotenoid as well as the number and volume of chloroplasts in mesophyll cells, while the mitigation of structural damage in the photosynthetic apparatus was weaker than that in tartaric acid or malic acid treatment. It is concluded that application of tartaric acid or malic acid is effective in increasing the growth potential of S. variegata under Cd stress and thus can be a promising approach for the phytoremediation of Cd-contaminated soil.


Assuntos
Cádmio/toxicidade , Malatos/farmacologia , Fotossíntese/efeitos dos fármacos , Salix/efeitos dos fármacos , Poluentes do Solo/toxicidade , Tartaratos/farmacologia , Biodegradação Ambiental , Disponibilidade Biológica , Biomassa , Cádmio/metabolismo , Clorofila/metabolismo , Cloroplastos/efeitos dos fármacos , Cloroplastos/metabolismo , Salix/crescimento & desenvolvimento , Salix/ultraestrutura , Poluentes do Solo/metabolismo
8.
Zhongguo Zhong Yao Za Zhi ; 43(16): 3291-3300, 2018 Aug.
Artigo em Zh | MEDLINE | ID: mdl-30200732

RESUMO

To screen the active fractions with lithagogue effects of Pyrrosia lingua from Guizhou province and preliminarily investigate its mechanism. The rats were fed with 1% ethylene glycol and 2% ammonium chloride to establish the nephrolithiasis models, which were used to evaluate thelithagogue effects of different polar fractions of P. lingua from Guizhou province. The level of urinary calcium and oxalic acid in urine, renal calcium, oxalic acid, superoxide dismutase (SOD), catalase(CAT) and malondialdehyde (MDA) in renal tissues,as well as crystalline deposit and lithogenesis in renal tissues and the levels of creatinine(Cr) and blood urea nitrogen (BUN) in the serum were detected. The effective compounds were inferred from the analysis of active fractions extract based on LC-MS technology. Petroleum ether fraction and dichloromethane fraction of P. lingua from Guizhou province can reduce renal oxalic acid and renal calcium concentration, increase urinary oxalic acid and urine calcium, with significant inhibitory effect on the formation of renal calculus in rats, significantly increase SOD and CAT activities in renal tissues, and significantly reduce MDA levels. LC-MS analysis showed that the caffeine, citric acid and tartaric acid among the compounds from petroleum ether fraction and dichloromethane fraction had lithagogue effects. Both the petroleum ether fraction and dichloromethane fraction of P. lingua from Guizhou province showed good effect on prevention and treatment of calculus in middle dose groups, and the mechanism may be associated with antioxidation, reducing calcium oxalate crystal deposition, and promoting calcium oxalatecrystal release, in addition, caffeine, citric acid and tartaric acid had lithagogue effects.


Assuntos
Oxalato de Cálcio , Medicamentos de Ervas Chinesas/farmacologia , Cálculos Renais/tratamento farmacológico , Polypodiaceae/química , Animais , Cafeína/farmacologia , Ácido Cítrico/farmacologia , Rim/efeitos dos fármacos , Ratos , Tartaratos/farmacologia
9.
Int J Mol Sci ; 18(6)2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28617325

RESUMO

Biopolymer films based on apple skin powder (ASP) and carboxymethylcellulose (CMC) were developed with the addition of apple skin extract (ASE) and tartaric acid (TA). ASP/CMC composite films were prepared by mixing CMC with ASP solution using a microfluidization technique to reduce particle size. Then, various concentrations of ASE and TA were incorporated into the film solution as an antioxidant and an antimicrobial agent, respectively. Fourier transform infrared (FTIR), optical, mechanical, water barrier, and solubility properties of the developed films were then evaluated to determine the effects of ASE and TA on physicochemical properties. The films were also analyzed for antioxidant effect on 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and antimicrobial activities against Listeria monocytogenes, Staphylococcus aureus, Salmonella enterica, and Shigella flexneri. From the results, the ASP/CMC film containing ASE and TA was revealed to enhance the mechanical, water barrier, and solubility properties. Moreover, it showed the additional antioxidant and antimicrobial properties for application as an active packaging film.


Assuntos
Anti-Infecciosos/química , Antioxidantes/química , Carboximetilcelulose Sódica/química , Embalagem de Alimentos/métodos , Malus/química , Extratos Vegetais/química , Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Infecções Bacterianas/prevenção & controle , Carboximetilcelulose Sódica/farmacologia , Microbiologia de Alimentos , Humanos , Listeria monocytogenes/efeitos dos fármacos , Microfluídica/instrumentação , Tamanho da Partícula , Extratos Vegetais/farmacologia , Salmonella enterica/efeitos dos fármacos , Shigella flexneri/efeitos dos fármacos , Solubilidade , Staphylococcus aureus/efeitos dos fármacos , Vapor , Tartaratos/química , Tartaratos/farmacologia
10.
Mol Vis ; 22: 548-62, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27293373

RESUMO

PURPOSE: Pathological angiogenesis and chronic inflammation greatly contribute to the development of choroidal neovascularization (CNV) in chorioretinal diseases involving abnormal contact between retinal pigment epithelial (RPE) and endothelial cells (ECs), associated with Bruch's membrane rupture. We explored the ability of the small organotellurium compound octa-O-bis-(R,R)-tartarate ditellurane (SAS) to mitigate inflammatory processes in human RPE cells. METHODS: Cell adhesion assays and analyses of gene and protein expression were used to examine the effect of SAS on ARPE-19 cells or primary human RPE cells that were grown alone or in an RPE-EC co-culture. RESULTS: Adhesion assays showed that SAS inhibited αv integrins expressed on RPE cells. Co-cultures of RPE cells with ECs significantly reduced the gene expression of PEDF, as compared to RPE cells cultured alone. Both SAS and the anti-αvß3 antibody LM609 significantly enhanced the production of PEDF at both mRNA and protein levels in RPE cells. RPE cells co-cultured with EC exhibited increased gene expression of CXCL5, COX1, MMP2, IGF1, and IL8, all of which are involved in both angiogenesis and inflammation. The enhanced expression of these genes was greatly suppressed by SAS, but interestingly, remained unaffected by LM609. Zymography assay showed that SAS reduced the level of MMP-2 activity in RPE cells. We also found that SAS significantly suppressed IL-1ß-induced IL-6 expression and secretion from RPE cells by reducing the protein levels of phospho-IkappaBalpha (pIκBα). CONCLUSIONS: Our results suggest that SAS is a promising anti-inflammatory agent in RPE cells, and may be an effective therapeutic approach for controlling chorioretinal diseases.


Assuntos
Anti-Inflamatórios/farmacologia , Inflamação/prevenção & controle , Compostos Organometálicos/farmacologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Tartaratos/farmacologia , Linhagem Celular , Quimiocina CXCL5/metabolismo , Técnicas de Cocultura , Ciclo-Oxigenase 1/metabolismo , Eletroforese em Gel de Poliacrilamida , Células Endoteliais/citologia , Ensaio de Imunoadsorção Enzimática , Proteínas do Olho/genética , Proteínas do Olho/metabolismo , Humanos , Inflamação/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Integrina alfaV/metabolismo , Interleucina-8/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Fatores de Crescimento Neural/genética , Fatores de Crescimento Neural/metabolismo , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Epitélio Pigmentado da Retina/metabolismo , Serpinas/genética , Serpinas/metabolismo , Telúrio/farmacologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
12.
Langmuir ; 31(43): 11875-85, 2015 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-26488599

RESUMO

Cationic amphiphiles have received increasing attention as antimicrobials given their unique ability to disrupt bacteria cell membranes. While extensive research has demonstrated that amphiphiles' hydrophobic-to-charge ratio significantly modulates antibacterial activity, less work has focused on elucidating the specific impact of charge location on amphiphile bioactivity. In this study, two series of cationic amphiphiles, termed bola-like and gemini-like, were synthesized with analogous hydrophobic-to-charge ratios yet differing charge location, and their resulting antibacterial activity was assessed. Bola-like amphiphiles exhibited preferential activity against two Gram-positive bacteria, with activity increasing with increasing hydrophobicity, whereas gemini-like amphiphiles were active against both Gram-positive and Gram-negative bacteria, with activity decreasing with increasing hydrophobicity. After identifying lead compounds from each amphiphile series (bola- and gemini-like), biophysical experiments indicated that both amphiphiles were membrane-active; notably, the lead gemini-like amphiphile exhibited a strong dependence on electrostatic interactions for membrane interaction. In contrast, the lead bola-like amphiphile exhibited a reliance on both hydrophobic and electrostatic contributions. These results demonstrate that charge location significantly impacts cationic amphiphiles' antibacterial and membrane activity.


Assuntos
Antibacterianos/química , Cátions/química , Tartaratos/química , Antibacterianos/farmacologia , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Tartaratos/farmacologia
13.
Langmuir ; 31(18): 5130-40, 2015 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-25879768

RESUMO

Carboxylate-rich organic acids play an important role in controlling the growth of apatite crystals and the extent of mineralization in the natural bone. The objective of this work was to investigate the effect of organic acids on calcium phosphate (CaP) nucleation on nanofiber microsheets functionalized with a glutamic acid peptide and osteogenic differentiation of human mesenchymal stem cells (hMSCs) seeded on the CaP-nucleated microsheets. High molecular weight poly(dl-lactide) (DL-PLA) was mixed with low molecular weight L-PLA conjugated with Glu-Glu-Gly-Gly-Cys peptide, and the mixture was electrospun to generate aligned nanofiber microsheets. The nanofiber microsheets were incubated in a modified simulated body fluid (mSBF) supplemented with different organic acids for nucleation and growth of CaP crystals on the nanofibers. Organic acids included citric acid (CA), hydroxycitric acid (HCA), tartaric acid (TART), malic acid (MA), ascorbic acid (AsA), and salicylic acid (SalA). HCA microsheets had the highest CaP content at 240 ± 10% followed by TART and CA with 225 ± 8% and 225 ± 10%, respectively. The Ca/P ratio and percent crystallinity of the nucleated CaP in TART microsheets was closest to that of stoichiometric hydroxyapatite. The extent of CaP nucleation and growth on the nanofiber microsheets depended on the acidic strength and number of hydrogen-bonding hydroxyl groups of the organic acids. Compressive modulus and degradation of the CaP nucleated microsheets were related to percent crystallinity and CaP content. Osteogenic differentiation of hMSCs seeded on the microsheets and cultured in osteogenic medium increased only for those microsheets nucleated with CaP by incubation in CA or AsA-supplemented mSBF. Further, only CA microsheets stimulated bone nodule formation by the seeded hMSCs.


Assuntos
Fosfatos de Cálcio/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanofibras/química , Oligopeptídeos/química , Ácido Ascórbico/farmacologia , Diferenciação Celular/efeitos dos fármacos , Citratos/farmacologia , Ácido Cítrico/farmacologia , Humanos , Malatos/farmacologia , Ácido Salicílico/farmacologia , Tartaratos/farmacologia
14.
Arch Microbiol ; 196(1): 51-61, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24322541

RESUMO

The antibacterial effects of a new organo-tellurium compound [Octa-O-bis-(R,R)-tartarate ditellurane (OTD)] on Escherichia coli isolates as a model are shown. OTD was found to be a bactericidal drug. It exhibits inhibition zones on a protein-rich agar medium but not in a protein-poor medium unless a thiol is added. When applied at the lag phase, OTD inhibits more efficiently than at the log phase. Thiols enhance the efficiency at the log phase. OTD inhibits biofilm formation of E. coli. X-ray microanalysis demonstrated damage caused to the Na⁺/K⁺ pumps and leakage of potassium and phosphorous. Scanning electron microscopy demonstrated an incomplete surface of the bacterial cell wall with a concavity in the center that looks like a hole. Transmission electron microscopy demonstrated severe damage, such as depletion, perforation, and holes in the inner membrane. These results indicate for the first time that the new tellurium compound has antibacterial activities.


Assuntos
Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Compostos Organometálicos/farmacologia , Tartaratos/farmacologia , Biofilmes/efeitos dos fármacos , Parede Celular/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão
15.
Exp Parasitol ; 137: 8-13, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24316462

RESUMO

Several ecto-enzymatic activities have been described in the plasma membrane of the protozoan Leishmania amazonensis, which is the major etiological agent of diffuse cutaneous leishmaniasis in South America. These enzymes, including ecto-phosphatases, contribute to the survival of the parasite by participating in phosphate metabolism. This work identifies and characterizes the extracellular hydrolysis of inorganic pyrophosphate related to an ecto-pyrophosphatase activity of the promastigote form of L. amazonensis. This ecto-pyrophosphatase activity is insensitive to MnCl2 but is strongly stimulated by MgCl2. This stimulation was not observed during the hydrolysis of p-nitrophenyl phosphate (p-NPP) or ß-glycerophosphate, two substrates for different ecto-phosphatases present in the L. amazonensis plasma membrane. Furthermore, extracellular PPi hydrolysis is more efficient at alkaline pHs, while p-NPP hydrolysis occurs mainly at acidic pHs. These results led us to conclude that extracellular PPi is hydrolyzed not by non-specific ecto-phosphatases but rather by a genuine ecto-pyrophosphatase. In the presence of 5mM MgCl2, the ecto-pyrophosphatase activity from L. amazonensis is sensitive to micromolar concentrations of NaF and millimolar concentrations of CaCl2. Moreover, this activity is significantly higher during the first days of L. amazonensis culture, which suggests a possible role for this enzyme in parasite growth.


Assuntos
Difosfatos/metabolismo , Leishmania mexicana/enzimologia , Pirofosfatases/metabolismo , Animais , Cloreto de Cálcio/farmacologia , Membrana Celular/enzimologia , Cloretos/farmacologia , Cricetinae , Relação Dose-Resposta a Droga , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Leishmania mexicana/crescimento & desenvolvimento , Leishmaniose Tegumentar Difusa/parasitologia , Levamisol/farmacologia , Cloreto de Magnésio/farmacologia , Compostos de Manganês/farmacologia , Pirofosfatases/antagonistas & inibidores , Pirofosfatases/efeitos dos fármacos , Fluoreto de Sódio/farmacologia , Tartaratos/farmacologia , Vanadatos/farmacologia
16.
Semin Cancer Biol ; 22(1): 60-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22202556

RESUMO

Tellurium is a rare element, which has been regarded as a toxic, non-essential trace element; its biological role, if any, has not been clearly established to date. The investigation of therapeutic activities of tellurium compounds is rather limited in the literature, despite the relative abundance of tellurium in the human body. Nevertheless, the varied activities of tellurium agents in both malignant and normal cells are extremely exciting, though very complex. Not surprisingly, an increased interest in tellurium among biological chemists and pharmacists has fuelled the search for more and more diverse tellurium compounds. The present review will focus on two small inorganic tellurium complexes, ammonium trichloro(dioxoethylene-O,O')tellurate (AS101) and Octa-O-bis-(R,R)-tartarate ditellurane (SAS), thoroughly investigated by us, converging at their anti-cancer properties, and elucidating their mechanism of action. AS101 is probably the most extensively studied synthetic tellurium compound from the standpoint of its biological activity. It is a potent immunomodulator (both in vitro and in vivo) with a variety of potential therapeutic applications. It is probably the only tellurium compound to be tested in phase I/II clinical studies in cancer patients. The effects of AS101 and SAS are primarily caused by their specific Te(IV) redox-modulating activities enabling the inactivation of cysteine proteases such as cathepsin B, inhibition of specific tumor survival proteins like survivin, or obstruction of tumor IL-10 production. All of these have profound consequences regarding anti-tumor activity or sensitization of tumors to chemotherapy. These properties, coupled with the excellent safety profile of the compounds, suggest promising anti-cancer therapeutic potential for tellurium compounds such as AS101 or SAS.


Assuntos
Antineoplásicos/uso terapêutico , Etilenos/uso terapêutico , Interleucina-10/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Compostos Organometálicos/uso terapêutico , Tartaratos/uso terapêutico , Adjuvantes Imunológicos/farmacologia , Adjuvantes Imunológicos/uso terapêutico , Animais , Antineoplásicos/farmacologia , Inibidores de Cisteína Proteinase/farmacologia , Inibidores de Cisteína Proteinase/uso terapêutico , Cães , Etilenos/farmacologia , Humanos , Fatores Imunológicos/fisiologia , Imunomodulação/fisiologia , Interleucina-10/metabolismo , Camundongos , Compostos Organometálicos/farmacologia , Ratos , Tartaratos/farmacologia
17.
Eur J Pharmacol ; 975: 176668, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38788791

RESUMO

Tartaric acid (TA) has been shown beneficial effects on blood pressure and lipid levels. However, its effect on non-alcoholic fatty liver disease (NAFLD) remains unknown. This study aimed to investigate the role of TA in experimental NAFLD. Mice were fed a Western diet for 8 weeks, followed by administration of TA or a vehicle for an additional 12 weeks while continuing on the Western diet. Blood biochemistry including transaminases and glucose tolerance test and liver tissue RNA sequencing (RNA-seq), lipid content, and histology were investigated. The HepG2 cell line was used to explore the mechanism by which TA regulates lipid metabolism. We found that TA significantly improved weight gain, insulin resistance, hepatic steatosis, inflammation and fibrosis in Western diet-fed mice. By comparing gene expression differences, we found that TA affects pathways related to lipid metabolism, inflammatory response, and fibrosis. Furthermore, TA effectively reduced oleic acid-induced lipid accumulation in HepG2 cells and downregulated the genes associated with fatty acid synthesis, which were enriched in the AMP-activated protein kinase (AMPK) signaling pathway. TA also enhanced the phosphorylation of AMPK which could be reverted by the AMPK inhibitor Compound C in HepG2 cells. Our study suggests that TA improves experimental NAFLD by activating the AMPK signaling pathway. These findings indicate that TA may serve as a potential therapy for the human NAFLD.


Assuntos
Proteínas Quinases Ativadas por AMP , Metabolismo dos Lipídeos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica , Transdução de Sinais , Tartaratos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Animais , Humanos , Células Hep G2 , Proteínas Quinases Ativadas por AMP/metabolismo , Transdução de Sinais/efeitos dos fármacos , Masculino , Camundongos , Tartaratos/farmacologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Modelos Animais de Doenças
18.
Biomacromolecules ; 14(8): 2463-9, 2013 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-23795777

RESUMO

Amphiphilic macromolecules (AMs) based on carbohydrate domains functionalized with poly(ethylene glycol) can inhibit the uptake of oxidized low density lipoprotein (oxLDL) and counteract foam cell formation, a key characteristic of early atherogenesis. To investigate the influence of lipophilicity and stereochemistry on the AMs' physicochemical and biological properties, mucic acid-based AMs bearing four aliphatic chains (2a) and tartaric acid-based AMs bearing two (2b and 2l) and four aliphatic chains (2g and 2k) were synthesized and evaluated. Solution aggregation studies suggested that both the number of hydrophobic arms and the length of the hydrophobic domain impact AM micelle sizes, whereas stereochemistry impacts micelle stability. 2l, the meso analogue of 2b, elicited the highest reported oxLDL uptake inhibition values (89%), highlighting the crucial effect of stereochemistry on biological properties. This study suggests that stereochemistry plays a critical role in modulating oxLDL uptake and must be considered when designing biomaterials for potential cardiovascular therapies.


Assuntos
Lipoproteínas LDL/metabolismo , Açúcares Ácidos/farmacologia , Tensoativos/farmacologia , Tartaratos/farmacologia , Aterosclerose/tratamento farmacológico , Células Cultivadas , Avaliação Pré-Clínica de Medicamentos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Lipoproteínas LDL/antagonistas & inibidores , Micelas , Nanopartículas/química , Tamanho da Partícula , Polietilenoglicóis/síntese química , Polietilenoglicóis/farmacologia , Estereoisomerismo , Açúcares Ácidos/síntese química , Tensoativos/síntese química , Tartaratos/síntese química
19.
Phys Chem Chem Phys ; 15(23): 9186-96, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23652787

RESUMO

The inhibitors of the Tumor Necrosis Factor-α Converting Enzyme represent promising tools for the treatment of Rheumatoid Arthritis, Multiple Sclerosis and other autoimmune diseases. In this work, using Hamiltonian Replica Exchange Molecular Dynamics simulations and atomistic force field we perform an accurate structural characterization of a group of tartrate-based inhibitors. The simulations highlight a correlation between the conformational landscape in bulk solvent and inhibition potency. Since the structures in bulk solvent are much more compact than the crystallographic bound state, we formulate the hypothesis of a two-step docking mechanism: (i) formation of an intermediate between the compact, hydroxyl exposing conformations in solution and the catalytic zinc ion; (ii) structural rearrangement in the active site of TACE of the zinc-tethered drug in the final binding conformation.


Assuntos
Proteínas ADAM/antagonistas & inibidores , Tartaratos/química , Tartaratos/farmacologia , Proteínas ADAM/química , Proteínas ADAM/metabolismo , Proteína ADAM17 , Domínio Catalítico , Humanos , Conformação Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Estereoisomerismo
20.
Poult Sci ; 92(5): 1425-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23571355

RESUMO

When assessing effects of decontamination techniques on counts of Campylobacter spp. on broiler meat, it is essential that the results reflect the variations that may exist. Decontamination studies often use high inoculation levels (10(7) to 10(8) cfu) and one or few strains of Campylobacter jejuni, thereby restricting the results to reflect only a limited part of the true situation. This study presents results from physical and chemical decontamination of broiler meat medallions using different strains and different initial concentrations of C. jejuni. For 3 strains of C. jejuni, mean log reductions obtained by freezing at -20°C for 7 d was significantly higher for an initial concentration of 10(7) cfu/sample on the meat compared with an initial concentration of 10(3) cfu/sample. For freezing at -20°C for 24 h or application of 6% tartaric acid and subsequent storage for 24 h, no statistically significant difference in reductions was found for initial concentrations ranging from 10(3) to 10(7) cfu per sample. The mean log reductions obtained by all techniques were strongly dependent on the strain tested. The results reveal that reductions obtained with high inoculation levels of C. jejuni (10(7) cfu/sample) or single or few strains of the species (or both) should not be interpreted as a generic result for the species. If inoculation studies cannot be replaced by investigations of naturally contaminated meat, we advise using a mixture of strains found in the production environment at levels as close as possible to the natural contamination level.


Assuntos
Antibacterianos/farmacologia , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/isolamento & purificação , Descontaminação/métodos , Congelamento , Indústria de Embalagem de Carne/métodos , Carne/microbiologia , Animais , Campylobacter jejuni/genética , Galinhas , Contagem de Colônia Microbiana , Fosfatos/farmacologia , Densidade Demográfica , Tartaratos/farmacologia , Fatores de Tempo
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