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1.
World J Microbiol Biotechnol ; 36(2): 24, 2020 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-31965331

RESUMEN

The study evaluated the antibacterial activity of chlorogenic acid (CA) against Salmonella Enteritidis S1, a foodborne pathogen in chilled fresh chicken. Its minimum inhibitory concentration for S. Enteritidis S1 was 2 mM. 1 MIC CA treatment reduced the viable count of S. Enteritidis S1 by 3 log cfu/g in chilled fresh chicken. Scanning electron microscopy examination indicated that CA induced the cell envelope damage of S. Enteritidis S1. Following this, 1-N-Phenylnaphthylamine assay and LPS content analysis indicated that CA induced the permeability of outer membrane (OM). Confocal laser scanning microscopy examination further demonstrated that CA acted on the inner membrane (IM). To support this, the release of intracellular protein and ATP after CA treatment was also observed. CA also suppressed the activities of malate dehydrogenase and succinate dehydrogenase, two main metabolic enzymes in TCA cycle and electron transport chain. Thus, damage of intracelluar and outer membranes as well as disruption of cell metabolism resulted in cell death eventually. The finding suggested that CA has the potential to be developed as a preservative to control S. Enteritidis associated foodborne diseases.


Asunto(s)
Antibacterianos/farmacología , Ácido Clorogénico/farmacología , Salmonella enteritidis/efectos de los fármacos , Animales , Proteínas Bacterianas/antagonistas & inhibidores , Membrana Celular/efectos de los fármacos , Pollos/microbiología , Recuento de Colonia Microbiana , Regulación Bacteriana de la Expresión Génica/efectos de los fármacos , Malato Deshidrogenasa/antagonistas & inhibidores , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Microscopía Electrónica de Rastreo , Salmonella enteritidis/enzimología , Salmonella enteritidis/crecimiento & desarrollo , Succinato Deshidrogenasa/antagonistas & inhibidores
2.
J Agric Food Chem ; 68(2): 633-641, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31891488

RESUMEN

As typical perfluorinated compounds (PFCs), perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have been detected in various environmental media and their toxic effects have been extensively studied. Nevertheless, it remains unclear how PFCs cause cell apoptosis in healthy hepatocytes by inducing oxidative stress at the subcellular and molecular levels. In this study, the apoptotic pathways induced by PFOA and PFOS were explored. Besides, the effects of PFCs on the structure and function of lysozyme (LYZ) were investigated. After PFOA and PFOS exposure, the cell membrane and mitochondrial membrane potential were damaged. Further, PFOA and PFOS increased intracellular Ca2+ levels to 174.41 ± 1.70 and 158.91 ± 5.94%, respectively. Ultimately, caspase-3 was activated, causing cell apoptosis. As an indirect antioxidant enzyme, the molecular structure of LYZ was destroyed after interacting with PFOA and PFOS. Both PFOA and PFOS bound to the active center of LYZ, leading to the decrease of LYZ activity to 91.26 ± 0.78 and 76.01 ± 4.86%, respectively. This study demonstrates that PFOA and PFOS inhibit LYZ function, which can reduce the body's ability to resist oxidative stress, and then lead to mitochondria-mediated apoptosis.


Asunto(s)
Ácidos Alcanesulfónicos/farmacología , Apoptosis/efectos de los fármacos , Caprilatos/farmacología , Fluorocarburos/farmacología , Hepatocitos/efectos de los fármacos , Calcio/metabolismo , Caspasa 3/metabolismo , Línea Celular , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Hepatocitos/citología , Hepatocitos/metabolismo , Humanos , Estrés Oxidativo/efectos de los fármacos
4.
BMC Plant Biol ; 19(1): 512, 2019 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-31752698

RESUMEN

BACKGROUND: Thaxtomin A (TA) is a natural cellulose biosynthesis inhibitor (CBI) synthesized by the potato common scab-causing pathogen Streptomyces scabies. Inhibition of cellulose synthesis by TA compromises cell wall organization and integrity, leading to the induction of an atypical program of cell death (PCD). These processes may facilitate S. scabies entry into plant tissues. To study the mechanisms that regulate the induction of cell death in response to inhibition of cellulose synthesis, we used Arabidopsis thaliana cell suspension cultures treated with two structurally different CBIs, TA and the herbicide isoxaben (IXB). RESULTS: The induction of cell death by TA and IXB was abrogated following pretreatment with the synthetic auxin 2,4-dichlorophenoxyacetic acid (2,4-D) and the natural auxin indole-3-acetic acid (IAA). The addition of auxin efflux inhibitors also inhibited the CBI-mediated induction of PCD. This effect may be due to intracellular accumulation of auxin. Auxin has a wide range of effects in plant cells, including a role in the control of cell wall composition and rigidity to facilitate cell elongation. Using Atomic Force Microscopy (AFM)-based force spectroscopy, we found that inhibition of cellulose synthesis by TA and IXB in suspension-cultured cells decreased cell wall stiffness to a level slightly different than that caused by auxin. However, the cell wall stiffness in cells pretreated with auxin prior to CBI treatment was equivalent to that of cells treated with auxin only. CONCLUSIONS: Addition of auxin to Arabidopsis cell suspension cultures prevented the TA- and IXB-mediated induction of cell death. Cell survival was also stimulated by inhibition of polar auxin transport during CBI-treatment. Inhibition of cellulose synthesis perturbed cell wall mechanical properties of Arabidopsis cells. Auxin treatment alone or with CBI also decreased cell wall stiffness, showing that the mechanical properties of the cell wall perturbed by CBIs were not restored by auxin. However, since auxin's effects on the cell wall stiffness apparently overrode those induced by CBIs, we suggest that auxin may limit the impact of CBIs by restoring its own transport and/or by stabilizing the plasma membrane - cell wall - cytoskeleton continuum.


Asunto(s)
Apoptosis/efectos de los fármacos , Arabidopsis/fisiología , Benzamidas/farmacología , Celulosa/biosíntesis , Ácidos Indolacéticos/metabolismo , Indoles/farmacología , Piperazinas/farmacología , Reguladores del Crecimiento de las Plantas/metabolismo , Arabidopsis/efectos de los fármacos , Calcio/metabolismo , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Pared Celular/efectos de los fármacos , Pared Celular/metabolismo , Células Cultivadas , Celulosa/antagonistas & inhibidores , Herbicidas/farmacología
5.
Int J Nanomedicine ; 14: 8483-8497, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31695376

RESUMEN

Introduction: Controlled delivery of therapeutic molecules in a localized manner has become an area of interest due to its potential to reduce drug exposure to healthy tissues and consequently to minimize undesirable side effects. We have recently introduced novel cell-penetrating vehicles by immobilizing the antimicrobial peptide Buforin II (BUF-II) on magnetite nanoparticles (MPNPs). Despite the potent translocating abilities of such nanobioconjugates, they failed to preserve the antimicrobial activity of native BUF-II. In this work, we explored immobilization on MNPs with the aid of polymer surface spacers, which has been considered as an attractive alternative for the highly efficient conjugation of various biomolecules. Methods: Here, we immobilized BUF-II on polyetheramine-modified magnetite nanoparticles to preserve its structural integrity. As a result, for the obtained nanobioconjugates the lost antimicrobial activity against gram-positive and gram-negative bacteria was only 50% with respect to the native BUF-II. The nanobioconjugates were also characterized via FTIR, DLS, TEM, and TGA. Delivery on THP-1, HaCaT, HFF, and Escherichia coli cells was conducted to confirm capability for cell membrane translocation. Results: Colocalization with Lysotracker showed an endosomal escape efficiency of about 73∓12% in THP-1 cells. Avoidance of endocytic pathways of internalization was qualitatively confirmed by a delivery assay at low temperature. Nuclear penetration of the nanobioconjugates was corroborated via confocal microscopy and showed high biocompatibility as demonstrated by hemolysis levels below 5% and acute cytotoxicity of around 15%. Conclusion: The obtained nanobioconjugates were capable of translocating the cell membrane and nuclei of different normal and cancerous cell lines without significantly decreasing viability. This makes the vehicle addressable for a number of applications ranging from antimicrobial topical treatments to the delivery of nucleotides and therapeutic molecules with difficulties to bypass cell membranes.


Asunto(s)
Aminas/química , Antibacterianos/farmacología , Péptidos de Penetración Celular/farmacología , Nanopartículas de Magnetita/química , Nanoconjugados/química , Proteínas/farmacología , Antibacterianos/química , Materiales Biocompatibles/farmacología , Línea Celular , Membrana Celular/efectos de los fármacos , Péptidos de Penetración Celular/química , Endocitosis/efectos de los fármacos , Endosomas/efectos de los fármacos , Endosomas/metabolismo , Escherichia coli/efectos de los fármacos , Escherichia coli/ultraestructura , Hemólisis/efectos de los fármacos , Humanos , Nanopartículas de Magnetita/ultraestructura , Proteínas/química
6.
Nat Commun ; 10(1): 4731, 2019 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-31636264

RESUMEN

Compounds with specific cytotoxic activity in senescent cells, or senolytics, support the causal involvement of senescence in aging and offer therapeutic interventions. Here we report the identification of Cardiac Glycosides (CGs) as a family of compounds with senolytic activity. CGs, by targeting the Na+/K+ATPase pump, cause a disbalanced electrochemical gradient within the cell causing depolarization and acidification. Senescent cells present a slightly depolarized plasma membrane and higher concentrations of H+, making them more susceptible to the action of CGs. These vulnerabilities can be exploited for therapeutic purposes as evidenced by the in vivo eradication of tumors xenografted in mice after treatment with the combination of a senogenic and a senolytic drug. The senolytic effect of CGs is also effective in the elimination of senescence-induced lung fibrosis. This experimental approach allows the identification of compounds with senolytic activity that could potentially be used to develop effective treatments against age-related diseases.


Asunto(s)
Apoptosis/efectos de los fármacos , Glicósidos Cardíacos/farmacología , Senescencia Celular/efectos de los fármacos , Condrocitos/efectos de los fármacos , Fibroblastos/efectos de los fármacos , Células A549 , Animales , Antibióticos Antineoplásicos/farmacología , Bleomicina/farmacología , Neoplasias de la Mama , Línea Celular Tumoral , Membrana Celular/efectos de los fármacos , Digoxina/farmacología , Femenino , Humanos , Concentración de Iones de Hidrógeno/efectos de los fármacos , Ratones , Osteoartritis , Ouabaína/farmacología , Proscilaridina/farmacología , Fibrosis Pulmonar , Ensayos Antitumor por Modelo de Xenoinjerto
7.
Aquat Toxicol ; 216: 105323, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31606665

RESUMEN

Graphene oxide (GO), used in a wide variety of applications, is increasingly being introduced into aquatic environments; this situation calls for research on GO toxicity to assess its environmental risks. In this study, the toxic effect of GO to E.coli was studied before and after its aggregation equilibrium in the synthetic surface waters (the soft water, moderately hard water, and hard water) to reveal the effects of GO aggregation and solution hardness. The cytotoxicity of GO increased with increasing solution hardness while decreased after GO aggregation. The 3 h 50% inhibitory concentration (IC50) values of dispersed GO in the soft water, moderately hard water, and hard water were 12.2 ±â€¯2.2, 8.5 ±â€¯1.5, and 4.0 ±â€¯1.0 mg/L, respectively. After 24 h shaking (aggregation equilibrium) in the synthetic surface waters, the dispersed GO aggregated and the 3 h IC50 values of GO aggregates in the three synthetic waters were 40.3 ±â€¯6.9, 15.9 ±â€¯ 2.2, and 7.5 ±â€¯1.5 mg/L, respectively. The dispersed GO sheets wrapped E. coli cells and cut the cell membrane, resulting in the disruption of cell membrane and the cell inactivation. With increasing water hardness, the heteroaggregation between GO sheets/aggregates and E. coli cells was enhanced, resulting in the increase of toxic effect. The GO aggregates could also entrap E.coli cells while exhibited limited effect on cell membrane disruption without sharp edges, thereby causing the lower toxic effect compared with the dispersed GO sheets. These outcomes shed new light on the assessment of ecological effects of GO.


Asunto(s)
Escherichia coli/efectos de los fármacos , Grafito/toxicidad , Microbiología del Agua , Agua/química , Muerte Celular/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Escherichia coli/citología , Escherichia coli/crecimiento & desarrollo , Escherichia coli/ultraestructura , Agua Dulce/microbiología , Dureza , Contaminantes Químicos del Agua/toxicidad
8.
Int J Nanomedicine ; 14: 7107-7121, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31564868

RESUMEN

Background: Cervical cancer (CxCa) ranks as the fourth most prevalent women-related cancer worldwide. Therefore, there is a crucial need to develop newer treatment modalities. Ormeloxifene (ORM) is a non-steroidal, selective estrogen receptor modulator (SERM) that is used as an oral contraceptive in humans. Recent investigations suggest that ORM exhibits potent anti-cancer activity against various types of cancers. Nanoparticulates offer targeted delivery of anti-cancer drugs with minimal toxicity and promise newer approaches for cancer diagnosis and treatment. Therefore, the nanotherapy approach is superior compared to traditional chemotherapy, which is not site-specific and is often associated with various side effects. Methods: Pursuing this novel nanotherapy approach, our lab has recently developed ORM-loaded poly [lactic-co-glycolic acid] (PLGA), an FDA-approved biodegradable polymer, nanoparticles to achieve targeted drug delivery and improved bioavailability. Our optimized PLGA-ORM nanoformulation showed improved internalization in both dose- and energy-dependent manners, through endocytosis-mediated pathways in both Caski and SiHa cell lines. Additionally, we employed MTS and colony forming assays to determine the short- and long-term effects of PLGA-ORM on these cells. Results: Our results showed that this formulation demonstrated improved inhibition of cellular proliferation and clonogenic potential compared to free ORM. Furthermore, the PLGA-ORM nanoformulation exhibited superior anti-tumor activities in an orthotopic cervical cancer mouse model than free ORM. Conclusion: Collectively, our findings suggest that our novel nanoformulation has great potential for repurposing the drug and becoming a novel modality for CxCa management.


Asunto(s)
Benzopiranos/uso terapéutico , Nanopartículas/uso terapéutico , Neoplasias del Cuello Uterino/tratamiento farmacológico , Animales , Benzopiranos/farmacología , Carcinogénesis/efectos de los fármacos , Carcinogénesis/metabolismo , Carcinogénesis/patología , Línea Celular Tumoral , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células Clonales , Modelos Animales de Enfermedad , Endocitosis/efectos de los fármacos , Eritrocitos/metabolismo , Femenino , Hemólisis/efectos de los fármacos , Humanos , Ensayo de Materiales , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones Desnudos , Copolímero de Ácido Poliláctico-Ácido Poliglicólico/química , Suero/química , Neoplasias del Cuello Uterino/patología
9.
Chemosphere ; 235: 995-1006, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31561316

RESUMEN

The influence of Cr(VI) on the degradation of tetrabromobisphenol A (TBBPA) by a typical species of white rot fungi, Pycnoporus sanguineus, was investigated in this study. The results showed that P. sanguineus together with its intracellular and extracellular enzyme could effectively degrade TBBPA. The degradation efficiency of TBBPA by both P. sanguineus and its enzymes decreased significantly when Cr(VI) concentration increased from 0 to 40 mg/L. The subsequent analysis about cellular distribution of TBBPA showed that the extracellular amount of TBBPA increased with the increment of Cr(VI) concentration, but the content of TBBPA inside fungal cells exhibited an opposite variation tendency. The inhibition of TBBPA degradation by P. sanguineus was partly attributed to the increase of cell membrane permeability and the decrease of cell membrane fluidity caused by Cr(VI). In addition, the decline of H+-ATPase and Mg2+-ATPase activities was also an important factor contributing to the suppression of TBBPA degradation in the system containing concomitant Cr(VI). Moreover, the activities of two typical extracellular lignin-degrading enzymes of P. sanguineus, MnP and Lac, were found to descend with ascended Cr(VI) level. Cr(VI) could also obviously suppress the gene expression of four intracellular enzymes implicated in TBBPA degradation, including two cytochrome P450s, glutathione S-transferases and pentachlorophenol 4-monooxygenase, which resulted in a decline of TBBPA degradation efficiency by fungal cells and intracellular enzyme in the presence of Cr(VI). Overall, this study provides new insights into the characteristics and mechanisms involved in TBBPA biodegradation by white rot fungi in an environment where heavy metals co-exist.


Asunto(s)
Biodegradación Ambiental , Cromo/toxicidad , Contaminantes Ambientales/metabolismo , Bifenilos Polibrominados/metabolismo , Pycnoporus/metabolismo , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Proteínas Fúngicas/metabolismo , Oxidación-Reducción , Pycnoporus/efectos de los fármacos , Pycnoporus/crecimiento & desarrollo
10.
Molecules ; 24(18)2019 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-31547303

RESUMEN

Better understanding the mechanisms of Leonurus cardiaca L. extract (LCE) activity is necessary to prepare recommendations for the use of LCE-based herbal products for preventive/supportive purposes in case of infective endocarditis (IE) and other staphylococcal invasive infections. The aim of the study was to analyze molecular mechanisms of LCE effect on Staphylococcus aureus and blood platelets in the context of their interactions playing a pivotal role in such disorders. Using atomic force microscopy, we demonstrated that adhesion forces of S. aureus were markedly reduced after exposure to LCE at subinhibitory concentrations. The effect resulted from the impact of LCE on S. aureus cell morphology and the composition of phospholipids and fatty acids in bacterial membranes (assessed by HPLC), which modulated their stabilization, hydrophobicity, and charge. Moreover, using FACS we showed also that LCE significantly reduced GP IIb/IIIa expression on blood platelets, thus the disruption of platelet-fibrinogen interactions seems to explain antiplatelet effect of LCE. The obtained results prove the usefulness of LCE in the prevention of S. aureus adhesion, platelet activation, and vegetations development, however, also pointed out the necessity of excluding the cationic antibiotics from the treatment of S. aureus-associated IE and other invasive diseases, when motherwort herb is used simultaneously as an addition to the daily diet.


Asunto(s)
Endocarditis Bacteriana/prevención & control , Leonurus/química , Extractos Vegetales/farmacología , Infecciones Estafilocócicas/prevención & control , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/farmacología , Adhesión Bacteriana/efectos de los fármacos , Plaquetas/efectos de los fármacos , Plaquetas/metabolismo , Plaquetas/microbiología , Membrana Celular/química , Membrana Celular/efectos de los fármacos , Endocarditis Bacteriana/microbiología , Ácidos Grasos/metabolismo , Fibrinógeno/metabolismo , Humanos , Microscopía de Fuerza Atómica , Fosfolípidos/metabolismo , Activación Plaquetaria/efectos de los fármacos , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/química , Staphylococcus aureus/patogenicidad
11.
Soft Matter ; 15(37): 7509-7526, 2019 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-31528961

RESUMEN

Antimicrobial peptides (AMPs) are naturally-occurring peptide antibiotics. AMPs are typically cationic and utilize their electrostatic interactions with the bacterial membrane to selectively attack bacteria. The way they work has inspired a vigorous search for optimized peptides for fighting resistant bacteria. Here, we present a physical model of membrane selectivity of AMPs. The challenge for theoretical modeling of membrane-peptide systems arises from the simultaneous presence of several competing effects, including lipid demixing and peptide-peptide interactions on the membrane surface. We first examine critically a number of models of peptide-membrane interactions and map out one, which incorporates adequately these competing effects as well as the geometry of various regions in membranes, occupied by bound peptides, anionic lipids within the interaction range of each peptide, and those outside this range. This effort leads to a systematically-improved model for peptide selectivity. Using the model, we relate peptide's intrinsic (Ccell-independent) selectivity to an apparent, Ccell-dependent one, and clarify the relative roles of peptide parameters and cell densities in determining their selectivity. This relationship suggests that the selectivity is more sensitive to peptide parameters at low cell densities; as a result, the optimal peptide charge, at which the selectivity is maximized, increases with the cell density in such a manner that this notion becomes less meaningful at high cell densities.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/química , Membrana Celular/química , Termodinámica , Péptidos Catiónicos Antimicrobianos/farmacología , Membrana Celular/efectos de los fármacos , Membrana Dobles de Lípidos/química , Modelos Teóricos
12.
Lett Appl Microbiol ; 69(5): 312-317, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31529504

RESUMEN

Andrias davidianus is widely recognized in traditional medicine as a cure-all to treat a plethora of ailments. In a previous study, a novel antibacterial peptide named andricin B was isolated from A. davidianus blood. In this study, we investigated andricin B structure and its mode of action. Circular dichroism spectra suggested that andricin B adopts a random coil state in aqueous solution and a more rigid conformation in the presence of bacteria. Moreover propidium iodide/fluorescein diacetate double staining indicated that bacteria treated with andricin B were not immediately eliminated. Rather, there is a gradual bacterial death, followed by a sublethal stage. Scanning electronic microscope imaging indicates that andricin B might form pores on cell membranes, leading to the release of cytoplasmic contents. These results were consistent with flow cytometry analysis. Furthermore, Fourier transform infrared spectroscopy suggests that andricin B induces changes in the chemical properties in the areas surrounding these "pores" on the cell membranes. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study suggested the new perspectives about the mode of action of antimicrobial peptide (AMP) active against sensitive bacteria. The AMP was able to be in a random coiled state in aqueous solution but to change to a more rigid one in the presence of sensitive bacteria. Exposure to AMP might not lead to immediate death of treated bacteria, rather bacteria concentration decreased gradually flattening at a sublethal stage. These findings will help people to understand better how the AMPs activate against sensitive bacteria.


Asunto(s)
Antibacterianos/química , Antibacterianos/farmacología , Péptidos/química , Péptidos/farmacología , Urodelos/sangre , Animales , Antibacterianos/sangre , Bacterias/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Dicroismo Circular , Pruebas de Sensibilidad Microbiana , Péptidos/sangre
13.
Cell Physiol Biochem ; 53(3): 573-586, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31529929

RESUMEN

BACKGROUND/AIMS: In our recent work, the importance of GSK3ß-mediated phosphorylation of presenilin-1 as crucial process to establish a Ca2+ leak in the endoplasmic reticulum and, subsequently, the pre-activation of resting mitochondrial activity in ß-cells was demonstrated. The present work is a follow-up and reveals the importance of GSK3ß-phosphorylated presenilin-1 for responsiveness of pancreatic islets and ß-cells to elevated glucose in terms of cytosolic Ca2+ spiking and insulin secretion. METHODS: Freshly isolated pancreatic islets and the two pancreatic ß-cell lines INS-1 and MIN-6 were used. Cytosolic Ca2+ was fluorometrically monitored using Fura-2/AM and cellular insulin content and secretion were measured by ELISA. RESULTS: Our data strengthened our previous findings of the existence of a presenilin-1-mediated ER-Ca2+ leak in ß-cells, since a reduction of presenilin-1 expression strongly counteracted the ER Ca2+ leak. Furthermore, our data revealed that cytosolic Ca2+ spiking upon administration of high D-glucose was delayed in onset time and strongly reduced in amplitude and frequency upon siRNA-mediated knock-down of presenilin-1 or the inhibition of GSK3ß in the pancreatic ß-cells. Moreover, glucose-triggered initial insulin secretion disappeared by depletion from presenilin-1 and inhibition of GSK3ß in the pancreatic ß-cells and isolated pancreatic islets, respectively. CONCLUSION: These data complement our previous work and demonstrate that the sensitivity of pancreatic islets and ß-cells to glucose illustrated as glucose-triggered cytosolic Ca2+ spiking and initial but not long-lasting insulin secretion crucially depends on a strong ER Ca2+ leak that is due to the phosphorylation of presenilin-1 by GSK3ß, a phenomenon that might be involved in the development of type 2 diabetes.


Asunto(s)
Retículo Endoplásmico/metabolismo , Glucosa/farmacología , Células Secretoras de Insulina/metabolismo , Islotes Pancreáticos/metabolismo , Presenilina-1/metabolismo , Animales , Antracenos/farmacología , Calcio/metabolismo , Línea Celular , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Retículo Endoplásmico/efectos de los fármacos , Humanos , Secreción de Insulina/efectos de los fármacos , Células Secretoras de Insulina/efectos de los fármacos , Islotes Pancreáticos/efectos de los fármacos , MAP Quinasa Quinasa 4/antagonistas & inhibidores , Masculino , Ratones , Ratones Endogámicos C57BL , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo
14.
Int J Med Sci ; 16(8): 1180-1187, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31523181

RESUMEN

Objective: The effects of pre-treatments from s-methyl cysteine (SMC) alone, syringic acid (SA) alone and SMC plus SA against kainic acid (KA) induced injury in nerve growth factor (NGF) differentiated PC12 cells were investigated. Methods: NGF-differentiated PC12 cells were treated with 1 µM SMC, 1 µM SA or 0.5 µM SMC plus 0.5 µM SA for 2 days. Subsequently, cells were further treated by 150 µM KA. Results: KA suppressed Bcl-2 mRNA expression, enhanced Bax mRNA expression and casued cell death. SMC was greater than SA, and similar as SMC+SA in increasing Bcl-2 mRNA expression. SMC+SA led to greater increase in mitochondrial membrane potential and cell survival than SMC or SA alone. SMC+SA resulted in more reduction in reactive oxygen species and tumor necrosis factor-alpha generation, more increase in glutathione content and glutathione reductase activity than SMC or SA alone. KA up-regulated protein expression of nuclear factor kappa B (NF-κB) p65 and phosphorylated p38 (p-p38). SMC or SA pre-treatments alone limited protein expression of both factors. SMC+SA resulted in more suppression in NF-κB p65 and p-p38 expression. KA decreased glutamine level, increased glutamate level and stimulated calcium release. SMC pre-treatments alone reversed these alterations. SMC alone elevated glutamine synthetase (GS) activity and mRNA expression. SMC+SA led to greater GS activity and mRNA expression than SMC pre-treatments alone. Conclusion: These findings suggested that this combination, SMC+SA, might provide greater protective potent for neuronal cells.


Asunto(s)
Cisteína/análogos & derivados , Ácido Gálico/análogos & derivados , Factor de Crecimiento Nervioso/farmacología , Fármacos Neuroprotectores/farmacología , Animales , Calcio/metabolismo , Diferenciación Celular/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Membrana Celular/patología , Supervivencia Celular , Cisteína/farmacología , Sinergismo Farmacológico , Ácido Gálico/farmacología , Ácido Kaínico/toxicidad , Potencial de la Membrana Mitocondrial/efectos de los fármacos , FN-kappa B/antagonistas & inhibidores , FN-kappa B/metabolismo , Estrés Oxidativo/efectos de los fármacos , Células PC12 , Ratas , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
15.
Phys Chem Chem Phys ; 21(36): 20211-20218, 2019 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-31486459

RESUMEN

In spite of their well-known side effects, the nonsteroidal anti-inflammatory drugs (NSAIDs) are one of the most commonly prescribed medications for their antipyretic and anti-inflammatory actions. Interaction of NSAIDs with the plasma membrane plays a vital role in their therapeutic actions and defines many of their side effects. In the present study, we investigate the effects of three NSAIDs, aspirin, ibuprofen, and indomethacin, on the structure and dynamics of a model plasma membrane using a combination of small angle neutron scattering (SANS) and neutron spin echo (NSE) techniques. The SANS and NSE measurements were carried out on a 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) membrane, with and without NSAIDs, at two different temperatures, 11 °C and 37 °C, where the DMPC membrane is in the gel and fluid phase, respectively. SANS data analysis shows that incorporation of NSAIDs leads to bilayer thinning of the membrane in both the phases. The dynamic properties of the membrane are represented by the intermediate scattering functions for NSE data, which are successfully described by the Zilman and Granek model. NSE data analysis shows that in both gel and fluid phases, addition of NSAIDs results in a decrease in the bending rigidity and compressibility modulus of the membrane, which is more prominent when the membrane is in the gel phase. The magnitude of the effect of NSAIDs on the bending rigidity and compressibility modulus of the membrane in the gel phase follows an order of ibuprofen > aspirin > indomethacin, whereas in the fluid phase, it is in the order of aspirin > ibuprofen > indomethacin. We find that the interaction between NSAIDs and phospholipid membranes is strongly dependent on the chemical structure of the drugs and physical state of the membrane. Mechanical properties of the membrane can be quantified by the membrane's bending rigidity. Hence, the present study reveals that incorporation of NSAIDs modulates the mechanical properties of the membrane, which may affect several physiological processes, particularly those linked to the membrane curvature.


Asunto(s)
Antiinflamatorios no Esteroideos/farmacología , Estructuras de la Membrana Celular/química , Estructuras de la Membrana Celular/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Neutrones , Dispersión del Ángulo Pequeño
16.
Life Sci ; 235: 116827, 2019 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-31479680

RESUMEN

OBJECTIVE: This study aims to evaluate the effective of azoles and MTX for patients with invasive candidiasis. METHODS: We used the disk diffusion assay and the checkerboard assay to evaluate the in vitro interactions between MTX and antifungals. In addition, we used the transmission electron microscopy to observe the ultrastructure of the effect of MTX and fluconazole on Candida albicans. RESULTS: The rates of synergy for the combination of MTX with fluconazole (FLC), itraconazole (ITC), and voriconazole (VRZ) were 91.3%, 65.2%, and 87% in checkerboard testing. No antagonism was found between methotrexate and azole antifungals in any of the strains. Furthermore, MTX treated C. albicans showed extensive cell wall vacuolations and the inhibition of blastospores growth, as observed using transmission electron microscopy. There was an apparent destruction of the cell membrane and cell wall resulting in the destruction of cytoplasm, a phenomenon observed when MTX was combined with azoles. CONCLUSION: This study provides evidence that the combination of azoles and MTX is effective for patients with invasive candidiasis, which on the other hand, will reduce the side effects of the drugs.


Asunto(s)
Candida albicans/efectos de los fármacos , Sinergismo Farmacológico , Fluconazol/farmacología , Itraconazol/farmacología , Metotrexato/farmacología , Voriconazol/farmacología , Membrana Celular/efectos de los fármacos , Pared Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Gástrula/efectos de los fármacos , Técnicas In Vitro , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Transmisión
17.
Curr Top Med Chem ; 19(23): 2114-2127, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31475899

RESUMEN

The Ras proteins play an important role in cell growth, differentiation, proliferation and survival by regulating diverse signaling pathways. Oncogenic mutant K-Ras is the most frequently mutated class of Ras superfamily that is highly prevalent in many human cancers. Despite intensive efforts to combat various K-Ras-mutant-driven cancers, no effective K-Ras-specific inhibitors have yet been approved for clinical use to date. Since K-Ras proteins must be associated to the plasma membrane for their function, targeting K-Ras plasma membrane localization represents a logical and potentially tractable therapeutic approach. Here, we summarize the recent advances in the development of K-Ras plasma membrane localization inhibitors including natural product-based inhibitors achieved from high throughput screening, fragment-based drug design, virtual screening, and drug repurposing as well as hit-to-lead optimizations.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Membrana Celular/efectos de los fármacos , Membrana Celular/metabolismo , Evaluación Preclínica de Medicamentos , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Proteína Oncogénica p21(ras)/metabolismo , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/uso terapéutico , Productos Biológicos/química , Productos Biológicos/farmacología , Reposicionamiento de Medicamentos , Humanos , Mutación , Neoplasias/genética , Neoplasias/patología , Proteína Oncogénica p21(ras)/genética
18.
World J Microbiol Biotechnol ; 35(9): 143, 2019 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-31493142

RESUMEN

Bacterial biofilms are multicellular aggregates enclosed in a self-created biopolymer matrix. Biofilm-producing bacteria have become a great public health problem worldwide because biofilms enable these microorganisms to evade several clearance mechanisms produced by host and synthetic sources. Over the past years, different flavonoids including quercetin have engrossed considerable interest among researchers owing to their potential anti-biofilm properties. To our knowledge, there is no review regarding effects of quercetin towards bacterial biofilms, prompting us to summarize experimental evidence on its anti-biofilm properties. Quercetin inhibits biofilm development by a diverse array of bacterial pathogens such as Enterococcus faecalis, Staphylococcus aureus, Streptococcus mutans, Escherichia coli, and Pseudomonas aeruginosa. Prevention of bacterial adhesion, suppression of quorum-sensing pathways, disruption or alteration of plasma membrane, inhibition of efflux pumps, and blocking nucleic acid synthesis have been documented as major anti-biofilm mechanisms of quercetin. Overall, anti-biofilm activity of quercetin can open up new horizons in a wide range of biomedical areas, from food industry to medicine.


Asunto(s)
Bacterias/efectos de los fármacos , Biopelículas/efectos de los fármacos , Quercetina/farmacología , Adhesión Bacteriana/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Membrana Celular/efectos de los fármacos , Pared Celular/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Inhibidores de la Síntesis del Ácido Nucleico/farmacología , Ácidos Nucleicos/biosíntesis , Percepción de Quorum/efectos de los fármacos
19.
Exp Parasitol ; 206: 107730, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31494215

RESUMEN

Phospholipids are the main component of membranes and are responsible for cell integrity. Alkylphospholipid analogues (APs) were first designed as antitumoral agents and were later tested against different cell types. Trypanosoma cruzi, the Chagas disease etiological agent, is sensitive to APs (edelfosine, miltefosine and ilmofosine) in vitro. We investigated the effect of synthetic ring substituted AP against epimastigotes, amastigotes and trypomastigotes. TCAN26, could inhibit the in vitro growth of epimastigotes and amastigotes with the 50% inhibitory concentrations (IC50) in the nanomolar range. Trypomastigotes lysis was also induced with 24-h treatment and a LC50 of 2.3 µM. Ultrastructural analysis by electron microscopy demonstrated that TCAN26 mainly affected the parasite's membranes leading to mitochondrial and Golgi cisternae swelling, membrane blebs, and autophagic figures in the different parasite developmental stages. While the Golgi of the parasites was significantly affected, the Golgi complex of the host cells remained normal suggesting a specific mechanism of action. In summary, our results suggest that TCAN 26 is a potent and selective inhibitor of T. cruzi growth probably due to disturbances of phospholipid biosynthesis.


Asunto(s)
Adamantano/farmacología , Fosforilcolina/análogos & derivados , Fosforilcolina/farmacología , Tripanocidas/farmacología , Trypanosoma cruzi/efectos de los fármacos , Adamantano/química , Animales , Antiprotozoarios/química , Antiprotozoarios/farmacología , Autofagia/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Enfermedad de Chagas/tratamiento farmacológico , Enfermedad de Chagas/parasitología , Relación Dosis-Respuesta a Droga , Citometría de Flujo , Aparato de Golgi/efectos de los fármacos , Concentración 50 Inhibidora , Dosificación Letal Mediana , Macrófagos Peritoneales/efectos de los fármacos , Ratones , Microscopía Electrónica de Rastreo , Microscopía Electrónica de Transmisión , Microscopía Fluorescente , Microscopía Inmunoelectrónica , Mitocondrias/efectos de los fármacos , Fosforilcolina/química , Tripanocidas/química , Trypanosoma cruzi/crecimiento & desarrollo , Trypanosoma cruzi/ultraestructura
20.
Plant Physiol Biochem ; 142: 528-535, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31473567

RESUMEN

Tryptophan at concentrations higher than 0.1 mM, triggered characteristic early physiological effects such as rapid (within 5 min) dose-dependent membrane hyperpolarization in Mimosa pudica motor cells and modification of the time course of the spontaneous proton efflux monitored in the incubation medium of pulvinar tissues. The rapid modifications of the leaf turgor-mediated movements seen on the primary pulvini of M. pudica following a shock and on Cassia fasciculata leaflets during a transition from light to darkness indicate that tryptophan disturbed the ionic migrations involved in the electrophysiological events and in the osmocontractile reaction of the motor cells. These reactions were specific to tryptophan compared to those induced by serine and 5-hydroxytryptophan. The tryptophan mode of action cannot be linked to a direct modification of the plasma membrane H+-ATPase activity as monitored on purified pulvinar plasma membrane vesicles. The tryptophan metabolism-linked products tryptamine and indole also inhibited the motile reactions, activated in a continuous manner the H+ secretion of pulvinar tissues and showed properties of a protonophore and an ATPase activity inhibitor on plasma membrane vesicles, respectively. The specific behavior of tryptophan in the reaction studies here is discussed in light of the previously reported action of phytohormones.


Asunto(s)
Cassia/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Mimosa/efectos de los fármacos , Triptófano/farmacología , Cassia/citología , Cassia/fisiología , Membrana Celular/metabolismo , Relación Dosis-Respuesta a Droga , Potenciales de la Membrana/efectos de los fármacos , Mimosa/citología , Mimosa/fisiología , Movimiento/efectos de los fármacos , Movimiento/fisiología , Hojas de la Planta/citología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/fisiología , Triptófano/metabolismo
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