Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 106
Filtrar
1.
Anticancer Agents Med Chem ; 24(5): 317-333, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-37936467

RESUMEN

AIMS: The aim of this study is to isolate the Millettia pinnata (Karanj) leaf extract for pure compound with anticancer properties and to study the molecular target of the isolates in non-small cell lung cancer cell lines. BACKGROUND: In our earlier research Millettia pinnata leaf extract has demonstrated potential anticancer activities. Thus, in pursuit of the bioactive compounds, the most potential active extract from our previous study was purified. Furthermore, the anticancer properties of the isolated compound karanjin was studied and aimed for apoptosis and restraining growth. METHODS: A novel method was developed through column chromatography for isolation and purification of the compound karanjin from leaf chloroform extract. The purified component was then characterised using FTIR, mass spectrometry, and NMR. An MTT-based cytotoxicity assay was used to analyse cell cytotoxicity, whereas fluorescence staining was used for apoptosis and reactive oxygen species inhibition quantification. Furthermore, the real-time PCR assay was used to determine the molecular mechanism of action in cells causing cytotoxicity induced by karanjin dosing. RESULTS: The anticancer activity of karanjin in A549 cell line exhibited prominent activity revealing IC50 value of 4.85 µM. Conferring the predicted molecular pathway study, karanjin restrains the proliferation of cancer cells through apoptosis, which is controlled by extrinsic pathway proteins FAS/FADD/Caspases 8/3/9. Downregulation of KRAS and dependent gene expression also stopped cell proliferation. CONCLUSION: Karanjin has been identified as a compound with potential effect in non-small cell lung cancer cells. Molecular mechanism for apoptosis and inhibition of reactive oxygen species induced through H2O2 were observed, concluding karanjin have medicinal and antioxidant properties.


Asunto(s)
Benzopiranos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Peróxido de Hidrógeno/farmacología , Neoplasias Pulmonares/tratamiento farmacológico , Línea Celular Tumoral , Apoptosis , Extractos Vegetales/farmacología , Modelos Teóricos
2.
Blood ; 142(19): 1658-1671, 2023 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-37624904

RESUMEN

Iron is an essential nutrient required by all cells but used primarily for red blood cell production. Because humans have no effective mechanism for ridding the body of excess iron, the absorption of dietary iron must be precisely regulated. The critical site of regulation is the transfer of iron from the absorptive enterocyte to the portal circulation via the sole iron efflux transporter, ferroportin. Here, we report that poly(rC)-binding protein 1 (PCBP1), the major cytosolic iron chaperone, is necessary for the regulation of iron flux through ferroportin in the intestine of mice. Mice lacking PCBP1 in the intestinal epithelium exhibit low levels of enterocyte iron, poor retention of dietary iron in enterocyte ferritin, and excess efflux of iron through ferroportin. Excess iron efflux occurred despite lower levels of ferroportin protein in enterocytes and upregulation of the iron regulatory hormone hepcidin. PCBP1 deletion and the resulting unregulated dietary iron absorption led to poor growth, severe anemia on a low-iron diet, and liver oxidative stress with iron loading on a high-iron diet. Ex vivo culture of PCBP1-depleted enteroids demonstrated no defects in hepcidin-mediated ferroportin turnover. However, measurement of kinetically labile iron pools in enteroids competent or blocked for iron efflux indicated that PCBP1 functioned to bind and retain cytosolic iron and limit its availability for ferroportin-mediated efflux. Thus, PCBP1 coordinates enterocyte iron and reduces the concentration of unchaperoned "free" iron to a low level that is necessary for hepcidin-mediated regulation of ferroportin activity.


Asunto(s)
Proteínas de Transporte de Catión , Sobrecarga de Hierro , Humanos , Ratones , Animales , Hierro/metabolismo , Hepcidinas/genética , Hepcidinas/metabolismo , Hierro de la Dieta/metabolismo , Proteínas de Transporte de Catión/genética , Proteínas de Transporte de Catión/metabolismo , Intestinos , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo
3.
Mol Divers ; 2023 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-37289383

RESUMEN

Cancer is one of the life-threatening diseases and the second leading cause of death in the world. The estrogen receptor can be considered as one of the significant drug targets for cancer. A large number of clinically used anticancer drugs were identified from phytochemicals. Multiple literatures suggested that extracts of Datura sp. significantly inhibit estrogen receptors associated with human cancer. In the present study, all reported natural products present in Datura sp. were subjected to molecular docking against estrogen receptors. The top hits were shortlisted based on binding orientation and docking score and subjected to molecular dynamics simulation to explore the conformational stability followed by binding energy calculation. The ligand [(1S,5R)-8-Methyl-8-Azabicyclo [3.2.1] Octan-3-yl] (2R)-3-Hydroxy-2-Phenylpropanoate depicts highly acceptable MD simulations outcomes and drug-likeness profile. Knowledge-based de novo design and similar ligand screening were executed using the structural information. The designed ligand DL-50 exhibited satisfactory binding, drug-likeness profile, and well-accepted ADMET profile followed by easy synthetic accessibility which further requires experimental validation.

4.
J Phys Chem A ; 127(6): 1512-1531, 2023 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-36695527

RESUMEN

It is generally challenging to obtain high-accuracy predictions for the heat of formation for species with more than a handful of heavy atoms, such as those of importance in standard combustion mechanisms. To this end, we construct the CBH-ANL approach and illustrate that, for a set of 194 alkane oxidation species, it can be used to produce ΔHf(0 K) values with 2σ uncertainties of 0.2-0.5 kcal mol-1. This set includes the alkanes, hydroperoxides, and alkyl, peroxy, and hydroperoxyalkyl radicals for 17 representative hydrocarbon fuels containing up to 10 heavy atoms with various degrees of branching in the alkane backbone. The CBH-ANL approach, automated in the QTC and AutoMech software suites, builds balanced chemical equations for the calculation of ΔHf(0 K), in which the reference species may be up to five heavy atoms. The high-level ANL0 and ANL1 reference ΔHf(0 K) values are further refined for even the largest of these reference species with a novel laddering approach. We perform a comprehensive quantification of the uncertainties for both the individual reference species (the largest of which is 0.15 kcal mol-1) and the propagation of those uncertainties when used in the calculation of ΔHf(0 K) for the 194 target species. We examine the sensitivity of the predicted ΔHf(0 K) values to (i) electronic energies from various methods, including ωB97X-D/cc-pVTZ, B2PLYP-D3/cc-pVTZ, CCSD(T)-F12b/cc-pVDZ-F12//B2PLYP-D3/cc-pVTZ, and CCSD(T)-F12b/cc-pVTZ-F12//B2PLYP-D3/cc-pVTZ; (ii) the zero-point vibrational energies (ZPVEs), where we consider harmonic ZPVEs as well as two scaling-based estimates of the anharmonic ZPVEs, all implemented for both ωB97X-D/cc-pVTZ and B2PLYP-D3/cc-pVTZ calculations; (iii) the particular CBH-ANL scheme employed; and (iv) the procedure for choosing the reference conformer for the analyses. The discussion concludes with a summary of the estimated overall uncertainty in the predictions and a validation of the predictions for the alkane subset.

5.
J Biomol Struct Dyn ; 41(9): 3926-3942, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-35412437

RESUMEN

The current global epidemic of the novel coronavirus (SARS-CoV-2) has been labeled a global public health emergency since it is causing substantial morbidity and mortality on daily basis. We need to identify an effective medication against SARS-CoV-2 because of its fast dissemination and re-emergence. This research is being carried out as part of a larger strategy to identify the most promising therapeutic targets using protein-protein interactions analysis. Mpro has been identified as one of the most important therapeutic targets. In this study, we did in-silico investigations to identify the target and further molecular docking, ADME, and toxicity prediction were done to assess the potential phyto-active antiviral compounds from Justicia adhatoda as powerful inhibitors of the Mpro of SARS-COV-2. We also investigated the capacity of these molecules to create stable interactions with the Mpro using 100 ns molecular dynamics simulation. The highest scoring compounds (taraxerol, friedelanol, anisotine, and adhatodine) were also found to exhibit excellent solubility and pharmacodynamic characteristics. We employed MMPBSA simulations to assess the stability of docked molecules in the Mpro binding site, revealing that the above compounds form the most stable complex with the Mpro. Network-based Pharmacology suggested that the selected compounds have various modes of action against SARS-CoV-2 that include immunoreaction enrichment, inflammatory reaction suppression, and more. These findings point to a promising class of drugs that should be investigated further in biochemical and cell-based studies to see their effectiveness against nCOVID-19.Communicated by Ramaswamy H. Sarma.


Asunto(s)
COVID-19 , Género Justicia , SARS-CoV-2 , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Hojas de la Planta , Inhibidores de Proteasas
6.
Turk J Pharm Sci ; 19(5): 488-497, 2022 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-36317842

RESUMEN

Objectives: Olaparib is an orally active poly (ADP-ribose) PARP (polymerases) inhibitor known to destroy cancer cells with BRCA1 or BRCA2 deficiency. An authentic, fast, distinct, and reliable reverse phase-high performance liquid chromatography (RP-HPLC) method was developed and promptly validated in tablet formulations for olaparib estimation. Materials and Methods: The proposed method focuses on the separation of olaparib in reverse phase mode using a Waters symmetry C18 (150 x 4.6 mm, 5 µm) analytical column with a flow rate of 1.0 mL/min and the injection volume was kept at 20 µL. The optimized mobile phase consists of ammonium acetate buffer (pH adjusted to 3.5 by glacial acetic acid): methanol in the ratio of 50:50 v/v. Results: The eluents were measured at 254 nm and the retention time for the drug encircled was about 4.32 min. The stress degradation studies of olaparib were conducted under acidic, alkaline, oxidative, photolytic and thermal conditions to demonstrate the stability of the drug. The regression value of 0.998 showed that the developed method was linear over the range of 80 µg/mL to 120 µg/mL. The developed RP-HPLC method is accurate and precise. The method was statistically validated as per International Conference on Harmonization guidelines. Conclusion: The proposed method is suitable and can be applied for the quantitative estimation of olaparib without any interference of the excipients used in the drug formulations.

7.
Heliyon ; 8(8): e10371, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36061025

RESUMEN

Cardiomyopathy is a primary cause of death in Friedreich ataxia (FRDA) patients with defective iron-sulfur cluster (ISC) biogenesis due to loss of functional frataxin and in rare patients with functional loss of other ISC biogenesis factors. The mechanistic target of rapamycin (mTOR) and AKT signaling cascades that coordinate eukaryotic cell growth and metabolism with environmental inputs, including nutrients and growth factors, are crucial regulators of cardiovascular growth and homeostasis. We observed increased phosphorylation of AKT and dysregulation of multiple downstream effectors of mTORC1, including S6K1, S6, ULK1 and 4EBP1, in a cardiac/skeletal muscle specific FRDA conditional knockout (cKO) mouse model and in human cell lines depleted of ISC biogenesis factors. Knockdown of several mitochondrial metabolic proteins that are downstream targets of ISC biogenesis, including lipoyl synthase and subunit B of succinate dehydrogenase, also resulted in activation of mTOR and AKT signaling, suggesting that mTOR and AKT hyperactivations are part of the metabolic stress response to ISC deficiencies. Administration of rapamycin, a specific inhibitor of mTOR signaling, enhanced the survival of the Fxn cKO mice, providing proof of concept for the potential of mTOR inhibition to ameliorate cardiac disease in patients with defective ISC biogenesis. However, AKT phosphorylation remained high in rapamycin-treated Fxn cKO hearts, suggesting that parallel mTOR and AKT inhibition might be necessary to further improve the lifespan and healthspan of ISC deficient individuals.

9.
Anticancer Agents Med Chem ; 22(14): 2577-2585, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35209821

RESUMEN

BACKGROUND: Laccifer lacca (Kerr) produces a mixture of polyhydroxy anthraquinones (laccaic acid) known as lac dye. Literature suggests that these laccaic acids have a structural resemblance with the anticancer drug Adriamycin (ADR). Hence, they may possess potential anticancer activity. METHODS: This study was designed to explore the in vitro anticancer activity of the three fractions of lac dye, i.e., chloroform (C), methanol (M), and water (W) fractions, and isolation of constituents from bioactive fraction. RESULTS: SRB (Sulforhodamine B) assay method was employed to evaluate the inhibitory action of all three fractions. However, only methanolic showed promising inhibitory action with GI50 <10; this runs in parallel with Adriamycin inhibition (GI50 <10). Two active constituents of the methanolic extract were isolated using column chromatography and were characterized using UV (UV visible spectrophotometer), IR (Infrared spectroscopy), NMR (nuclear magnetic resonance), and mass spectrometry methods. The final structure of the isolated constituents (laccaic acid D and laccaic acid B) was confirmed by 13C and 2D NMR data. CONCLUSION: Conclusively, only the methanol fraction (M) showed promising anticancer activity against in vitro MDAMB- 231 and SiHa cell lines compared to the standard adriamycin.


Asunto(s)
Compuestos Azo , Metanol , Línea Celular , Doxorrubicina/farmacología , Humanos , Extractos Vegetales/farmacología
10.
J Biomol Struct Dyn ; 40(15): 6989-7001, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-33682606

RESUMEN

Since time immemorial natural products have been a great source of medicine to mankind. The anti-viral activities from several ayurvedic herbal medicines (in the form of crude extract or fraction or isolated compounds) have been established but their effectiveness against coronavirus still needs to be explored. They can provide a rich resource of anti-SARS-CoV-2 drug candidates. In this paper, in-silico techniques have been used to identify the potential lead molecules against SARS-CoV-2. A list of flavonoids having anti-viral activity was prepared and evaluated against the selected target. Rhoifolin, 5,7-dimethoxyflavanone-4'-O-ß-d-glucopyranoside, baicalin, astragalin, luteolin, and kaempferol showed good binding affinity and thus these could be promising compounds. In-silico screening such as ADMET prediction has been performed which predicted that the selected flavonoids have good pharmacokinetics and pharmacodynamics properties. Molecular dynamics simulation studies and MM-PBSA binding free energy calculations showed luteolin to be a more effective candidate against viral protein Mpro. The novelty of the approach mainly rests in the identification of potent anti-viral natural molecules from natural products flavonoid group of molecules to be effective against the latest coronavirus infection.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Productos Biológicos , Tratamiento Farmacológico de COVID-19 , Antivirales/química , Antivirales/farmacología , Antivirales/uso terapéutico , Productos Biológicos/farmacología , Productos Biológicos/uso terapéutico , Flavonoides/química , Flavonoides/farmacología , Flavonoides/uso terapéutico , Humanos , Luteolina/farmacología , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Inhibidores de Proteasas/química , SARS-CoV-2
11.
PLoS Biol ; 19(12): e3001480, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34914695

RESUMEN

Mutations in leucine-rich repeat kinase 2 (LRRK2) cause autosomal dominant Parkinson disease (PD), while polymorphic LRRK2 variants are associated with sporadic PD. PD-linked mutations increase LRRK2 kinase activity and induce neurotoxicity in vitro and in vivo. The small GTPase Rab8a is a LRRK2 kinase substrate and is involved in receptor-mediated recycling and endocytic trafficking of transferrin, but the effect of PD-linked LRRK2 mutations on the function of Rab8a is poorly understood. Here, we show that gain-of-function mutations in LRRK2 induce sequestration of endogenous Rab8a to lysosomes in overexpression cell models, while pharmacological inhibition of LRRK2 kinase activity reverses this phenotype. Furthermore, we show that LRRK2 mutations drive association of endocytosed transferrin with Rab8a-positive lysosomes. LRRK2 has been nominated as an integral part of cellular responses downstream of proinflammatory signals and is activated in microglia in postmortem PD tissue. Here, we show that iPSC-derived microglia from patients carrying the most common LRRK2 mutation, G2019S, mistraffic transferrin to lysosomes proximal to the nucleus in proinflammatory conditions. Furthermore, G2019S knock-in mice show a significant increase in iron deposition in microglia following intrastriatal LPS injection compared to wild-type mice, accompanied by striatal accumulation of ferritin. Our data support a role of LRRK2 in modulating iron uptake and storage in response to proinflammatory stimuli in microglia.


Asunto(s)
Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/genética , Proteínas de Unión al GTP rab/metabolismo , Anciano , Animales , Transporte Biológico , Cuerpo Estriado , Mutación con Ganancia de Función/genética , Células HEK293 , Humanos , Hierro/metabolismo , Proteína 2 Quinasa Serina-Treonina Rica en Repeticiones de Leucina/metabolismo , Lisosomas/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Microglía , Persona de Mediana Edad , Mutación , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/metabolismo , Proteínas Serina-Treonina Quinasas , Transferrina/metabolismo , Transferrinas/genética , Transferrinas/metabolismo , Proteínas de Unión al GTP rab/genética
12.
Proc Natl Acad Sci U S A ; 118(40)2021 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-34593646

RESUMEN

Iron is an essential biometal, but is toxic if it exists in excess. Therefore, iron content is tightly regulated at cellular and systemic levels to meet metabolic demands but to avoid toxicity. We have recently reported that adaptive thermogenesis, a critical metabolic pathway to maintain whole-body energy homeostasis, is an iron-demanding process for rapid biogenesis of mitochondria. However, little information is available on iron mobilization from storage sites to thermogenic fat. This study aimed to determine the iron-regulatory network that underlies beige adipogenesis. We hypothesized that thermogenic stimulus initiates the signaling interplay between adipocyte iron demands and systemic iron liberation, resulting in iron redistribution into beige fat. To test this hypothesis, we induced reversible activation of beige adipogenesis in C57BL/6 mice by administering a ß3-adrenoreceptor agonist CL 316,243 (CL). Our results revealed that CL stimulation induced the iron-regulatory protein-mediated iron import into adipocytes, suppressed hepcidin transcription, and mobilized iron from the spleen. Mechanistically, CL stimulation induced an acute activation of hypoxia-inducible factor 2-α (HIF2-α), erythropoietin production, and splenic erythroid maturation, leading to hepcidin suppression. Disruption of systemic iron homeostasis by pharmacological HIF2-α inhibitor PT2385 or exogenous administration of hepcidin-25 significantly impaired beige fat development. Our findings suggest that securing iron availability via coordinated interplay between renal hypoxia and hepcidin down-regulation is a fundamental mechanism to activate adaptive thermogenesis. It also provides an insight into the effects of adaptive thermogenesis on systemic iron mobilization and redistribution.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Hepcidinas/metabolismo , Hierro/metabolismo , Termogénesis/fisiología , Adipocitos/metabolismo , Adipocitos Beige/metabolismo , Adipogénesis/fisiología , Tejido Adiposo Beige/metabolismo , Animales , Regulación hacia Abajo/fisiología , Eritropoyetina/metabolismo , Homeostasis/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Mitocondrias/metabolismo , Transducción de Señal/fisiología
13.
Semin Hematol ; 58(3): 161-174, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34389108

RESUMEN

To maintain an adequate iron supply for hemoglobin synthesis and essential metabolic functions while counteracting iron toxicity, humans and other vertebrates have evolved effective mechanisms to conserve and finely regulate iron concentration, storage, and distribution to tissues. At the systemic level, the iron-regulatory hormone hepcidin is secreted by the liver in response to serum iron levels and inflammation. Hepcidin regulates the expression of the sole known mammalian iron exporter, ferroportin, to control dietary absorption, storage and tissue distribution of iron. At the cellular level, iron regulatory proteins 1 and 2 (IRP1 and IRP2) register cytosolic iron concentrations and post-transcriptionally regulate the expression of iron metabolism genes to optimize iron availability for essential cellular processes, including heme biosynthesis and iron-sulfur cluster biogenesis. Genetic malfunctions affecting the iron sensing mechanisms or the main pathways that utilize iron in the cell cause a broad range of human diseases, some of which are characterized by mitochondrial iron accumulation. This review will discuss the mechanisms of systemic and cellular iron sensing with a focus on the main iron utilization pathways in the cell, and on human conditions that arise from compromised function of the regulatory axes that control iron homeostasis.


Asunto(s)
Eritropoyesis , Hierro , Animales , Homeostasis , Humanos , Hierro/metabolismo , Mamíferos/metabolismo
14.
Blood ; 137(18): 2509-2519, 2021 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-33512384

RESUMEN

Polycythemia and pulmonary hypertension are 2 human diseases for which better therapies are needed. Upregulation of hypoxia-inducible factor-2α (HIF-2α) and its target genes, erythropoietin (EPO) and endothelin-1, causes polycythemia and pulmonary hypertension in patients with Chuvash polycythemia who are homozygous for the R200W mutation in the von Hippel Lindau (VHL) gene and in a murine mouse model of Chuvash polycythemia that bears the same homozygous VhlR200W mutation. Moreover, the aged VhlR200W mice developed pulmonary fibrosis, most likely due to the increased expression of Cxcl-12, another Hif-2α target. Patients with mutations in iron regulatory protein 1 (IRP1) also develop polycythemia, and Irp1-knockout (Irp1-KO) mice exhibit polycythemia, pulmonary hypertension, and cardiac fibrosis attributable to translational derepression of Hif-2α, and the resultant high expression of the Hif-2α targets EPO, endothelin-1, and Cxcl-12. In this study, we inactivated Hif-2α with the second-generation allosteric HIF-2α inhibitor MK-6482 in VhlR200W, Irp1-KO, and double-mutant VhlR200W;Irp1-KO mice. MK-6482 treatment decreased EPO production and reversed polycythemia in all 3 mouse models. Drug treatment also decreased right ventricular pressure and mitigated pulmonary hypertension in VhlR200W, Irp1-KO, and VhlR200W;Irp1-KO mice to near normal wild-type levels and normalized the movement of the cardiac interventricular septum in VhlR200Wmice. MK-6482 treatment reduced the increased expression of Cxcl-12, which, in association with CXCR4, mediates fibrocyte influx into the lungs, potentially causing pulmonary fibrosis. Our results suggest that oral intake of MK-6482 could represent a new approach to treatment of patients with polycythemia, pulmonary hypertension, pulmonary fibrosis, and complications caused by elevated expression of HIF-2α.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/antagonistas & inhibidores , Regulación de la Expresión Génica/efectos de los fármacos , Hipertensión Pulmonar/prevención & control , Proteína 1 Reguladora de Hierro/fisiología , Policitemia/prevención & control , Sulfonas/farmacología , Proteína Supresora de Tumores del Síndrome de Von Hippel-Lindau/fisiología , Animales , Endotelina-1/antagonistas & inhibidores , Endotelina-1/genética , Endotelina-1/metabolismo , Eritropoyetina/antagonistas & inhibidores , Eritropoyetina/genética , Eritropoyetina/metabolismo , Femenino , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/metabolismo , Hipertensión Pulmonar/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Policitemia/etiología , Policitemia/metabolismo , Policitemia/patología
15.
Hepatology ; 73(3): 1176-1193, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32438524

RESUMEN

BACKGROUND AND AIMS: Iron is essential yet also highly chemically reactive and potentially toxic. The mechanisms that allow cells to use iron safely are not clear; defects in iron management are a causative factor in the cell-death pathway known as ferroptosis. Poly rC binding protein 1 (PCBP1) is a multifunctional protein that serves as a cytosolic iron chaperone, binding and transferring iron to recipient proteins in mammalian cells. Although PCBP1 distributes iron in cells, its role in managing iron in mammalian tissues remains open for study. The liver is highly specialized for iron uptake, utilization, storage, and secretion. APPROACH AND RESULTS: Mice lacking PCBP1 in hepatocytes exhibited defects in liver iron homeostasis with low levels of liver iron, reduced activity of iron enzymes, and misregulation of the cell-autonomous iron regulatory system. These mice spontaneously developed liver disease with hepatic steatosis, inflammation, and degeneration. Transcriptome analysis indicated activation of lipid biosynthetic and oxidative-stress response pathways, including the antiferroptotic mediator, glutathione peroxidase type 4. Although PCBP1-deleted livers were iron deficient, dietary iron supplementation did not prevent steatosis; instead, dietary iron restriction and antioxidant therapy with vitamin E prevented liver disease. PCBP1-deleted hepatocytes exhibited increased labile iron and production of reactive oxygen species (ROS), were hypersensitive to iron and pro-oxidants, and accumulated oxidatively damaged lipids because of the reactivity of unchaperoned iron. CONCLUSIONS: Unchaperoned iron in PCBP1-deleted mouse hepatocytes leads to production of ROS, resulting in lipid peroxidation (LPO) and steatosis in the absence of iron overload. The iron chaperone activity of PCBP1 is therefore critical for limiting the toxicity of cytosolic iron and may be a key factor in preventing the LPO that triggers the ferroptotic cell-death pathway.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Hígado Graso/etiología , Compuestos de Hierro/metabolismo , Peroxidación de Lípido , Metalochaperonas/metabolismo , Proteínas de Unión al ARN/metabolismo , Animales , Hígado Graso/metabolismo , Hígado Graso/patología , Femenino , Hepatocitos/metabolismo , Humanos , Hígado/metabolismo , Hígado/patología , Masculino , Ratones Noqueados , Estrés Oxidativo
16.
Comb Chem High Throughput Screen ; 23(7): 624-648, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32297572

RESUMEN

BACKGROUND: The Arisaema (Araceae) is a genus of approximately 180 perennial herbs widely distributed in the evergreen and deciduous forests. This genus (Arisaema) has been used as a medicinal agent since ancient times. Experimental investigations have shown a promising positive correlation with its folklore claim and this encourages us to report updated medicinal review (genus Arisaema) for future research. OBJECTIVE: This review aimed to summarize the ethnobotany, folklore uses, chemistry and biological activities. CONCLUSION: The comprehensive literature on genus Arisaema indicates the presence of terpenoids, flavonoids, and glycosphingolipids as the principal chemical constituents. Additionally, phytosterols, alkaloids, carboline derivatives and miscellaneous compounds were documented in plants of genus Arisaema. Biological investigations led to the credentials of antioxidant, anticancer, insecticidal, antimicrobial, anthelmintic and hepatoprotective activities. Following, several plant species are promising candidates for the treatment of cancer, parasitic diseases and microbial infection complications. Though, a lot of facets of this genus like phytoconstituents identification, mechanistic profile, adverse effects and clinical studies are still quite limited. Thus, this systematic review may act as a powerful tool in future studies for promoting health benefits against various health hazards.


Asunto(s)
Antiinfecciosos/farmacología , Antineoplásicos Fitogénicos/farmacología , Antiparasitarios/farmacología , Arisaema/química , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , Antiinfecciosos/química , Antineoplásicos Fitogénicos/química , Antiparasitarios/química , Humanos , Fitoquímicos/química , Extractos Vegetales/química , Plantas Medicinales
17.
Planta Med ; 86(4): 267-275, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31968380

RESUMEN

Infections caused by HSV-2 are a public health concern worldwide, and there is still a great demand for the discovery of novel anti-herpes virus agents effective against strains resistant to current antiviral agents. In this context, medicinal plants represent an alternative source of active compounds for developing efficient antiviral therapies. The aim of this study was to evaluate the antiviral activity of Arisaema tortuosum, a plant used in the traditional medicine of India. A chloroform soluble fraction of the leaves exhibited anti-HSV-2 activity with a selectivity index of 758. The extract was also active against acyclovir-resistant HSV-2 and HSV-1. The mechanism of action of the extract was investigated evidencing inhibition of both early and late events of the HSV-2 replicative cycle. A HPLC-PDA-MS/MS analysis showed the presence of flavonoids including apigenin and luteolin in the chloroform extract (CE). Apigenin and luteolin showed a high inhibitory activity with EC50 values of 0.05 and 0.41 µg/mL, respectively. Both compounds exhibited antiviral activity when added up to 6 h post infection and were able to reduce the viral progeny production. In addition, apigenin interfered with cell-to-cell virus spread.


Asunto(s)
Antivirales , Arisaema , Herpes Simple , Herpesvirus Humano 2 , India , Extractos Vegetales , Espectrometría de Masas en Tándem , Células Vero
18.
J Chromatogr Sci ; 58(4): 309-322, 2020 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-31836899

RESUMEN

Nateglinide (NAT) and Pioglitazone (PIO) are an antidiabetic drugs combination and currently under clinical trial in countries like Japan. In this study, an alternative, a simple, sensitive high-performance liquid chromatography method has been developed (limit of detection: 15 ng/mL and limit of quantification: 50 ng/mL) for simultaneous estimation of this drug combination in rat plasma. Most remarkably, bioavailability of NAT has been increased markedly on coadministration with PIO, than when it was administered alone. Thus, PIO is assumed to retard the catabolism of NAT by inhibiting metabolic liver-microsomal enzyme, especially CYP2C9. Using a Waters Nova-Pak C 18 column (150 × 3.9 mm, 4 µm) and a mobile phase of acetonitrile: 10 mM KH2PO4 (60: 40, V/V (volume by volume)) pH 3.5, the analysis was performed at 210 nm with a flow rate of 1.5 mL/min. In silico docking via molecular dynamics simulation revealed that NAT-CYP2C9 binding affinity may be reduced after PIO attachment, presumably due to the binding site overlapping of the two drugs. Thus, it has been proposed that NAT and PIO may be an efficient synergistic fixed dose combination against diabetes mellitus, and the above method can foster a simple but highly sensitive bioanalytical estimation for routine analysis.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Cromatografía de Fase Inversa/métodos , Nateglinida/farmacocinética , Pioglitazona/farmacocinética , Administración Oral , Animales , Disponibilidad Biológica , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/metabolismo , Estabilidad de Medicamentos , Sinergismo Farmacológico , Hipoglucemiantes/farmacocinética , Límite de Detección , Masculino , Ratones , Microsomas Hepáticos/efectos de los fármacos , Microsomas Hepáticos/metabolismo , Simulación de Dinámica Molecular , Nateglinida/administración & dosificación , Nateglinida/sangre , Nateglinida/química , Pioglitazona/administración & dosificación , Pioglitazona/sangre , Pioglitazona/química , Ratas , Reproducibilidad de los Resultados
19.
IET Nanobiotechnol ; 13(6): 626-633, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31432797

RESUMEN

Green synthesis of gold nanoparticles (GNPs) has received substantial attention, because nanoparticles are produced in an eco-friendly way using biomolecules present in plant extracts in a single step reaction. This research article highlights GNPs obtained using shade-dried leaf extracts of Millettia pinnata (L.) with aqueous auric chloride (HAuCl4) at ambient temperature. In the present study, GNPs with average particle size 37 nm in size were fabricated. Furthermore, the synthesis method to obtain stable and monodispersed GNPs was advanced by optimising enzyme concentration 100 µg/ml, pH 5.4, substrate concentration 0.45 mM and 12 h time of reaction. The confirmation of GNPs formation and characterisation was followed by UV-vis-absorption spectroscopy, dynamic light scattering (DLS), and zeta potential (ZP) for the analysis of shape, size, and stability, respectively. TEM images and powder XRD revealed the GNPs synthesis of spherical-shaped nanoparticles in the face-centred cubic arrangement. Cytotoxicity of GNPs was studied against A549 lung cancer cells with IC50 14.76 µg/ml and found lower as compared to doxorubicin IC50 11.23 µg/ml but significant enough to be used as a vehicle GNPs produced using green source can be used as significant therapeutic agents and drug delivery carriers.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/farmacología , Carcinoma de Pulmón de Células no Pequeñas/patología , Oro/química , Neoplasias Pulmonares/patología , Nanopartículas del Metal/química , Millettia/química , Células A549 , Antineoplásicos/química , Antioxidantes/síntesis química , Antioxidantes/química , Antioxidantes/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Ensayos de Selección de Medicamentos Antitumorales , Tecnología Química Verde/métodos , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Nanopartículas del Metal/uso terapéutico , Extractos Vegetales/química , Hojas de la Planta/química
20.
Phys Chem Chem Phys ; 21(32): 17993-18011, 2019 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-31386704

RESUMEN

A detailed systematic theoretical study of the mechanism of the homogeneous Brønsted-acid catalysis of d-glucose in aqueous solution phase ("acid hydrolysis") is reported. G4MP2 with the SMD solvation model at B3LYP/6-31G(2df,p) are employed to compute the free energies of the molecular and ionic species pertaining to the isomerization, protonation, hydrogen cation transfer and decomposition processes of d-glucopyranose in aqueous solution phase. This information is used to hypothesise a reaction mechanism that is of improved accuracy and completeness from the existing art. It is found that rotation of the d-glucose alkyl carbon-carbon bond is a facile process and is very important to the subsequent catalytic mechanism. This rotation produces two rotameric isomers which are of notably different thermodynamic stability and reactivity, even with regard to the products of this acid catalysis. As a low energy process (ΔG‡ = ∼3.8-6.7 kcal mol-1), the alkyl carbon-carbon bond may rotate toward the hydroxyl group at the adjacent "4" position reducing the energy required to protonate that position by 3.0-7.2 kcal mol-1 (or 15-30%). The combination of two rotomeric isomers with the six structural isomers owing to the oxygen atoms, means that protonated d-glucose cations embark on a complex competition of interconversion and decomposition that is both thermodynamically and kinetically influenced. The calculations support the hypothesis that the acid-catalysed hydrolysis of d-glucose may yield a number of platform chemicals that have not previously been suggested. These include the prospect of three isomers of 5-hydroxymethylfurfural (HMF); 5-(hydroxymethyl)furan-2-carbaldehyde, 5-(hydroxymethyl)furan-3-carbaldehyde and 5-(hydroxymethyl)furan-4-carbaldehyde. Vibrational spectra of these HMF isomers are also computed and compared to experimentally determined infrared spectra of "humins". On this basis, it is cautiously speculated that the alternative HMF isomers, may be monomeric constituent of the polymeric "humins".

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...