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1.
Int J Biol Macromol ; 118(Pt B): 1995-2000, 2018 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-30009916

RESUMEN

Compared to other complications the genetics of diabetic foot ulcer is poorly studied. The Interleukin (IL)-6 (-174G > C/rs1800795), Tumor Necrosis Factor (TNF)-α (-308G > A/rs1800629) and (-238G > A/rs361525) and Stromal cell Derived Factor (SDF)-1 (+801G > A/rs1801157) are well characterized single nucleotide polymorphisms (SNPs) which were previously shown to be associated with Diabetic Foot Ulcer (DFU). In the present study, we looked at the association of these SNPs with foot microbial infection, Wagner's ulcer grade and treatment procedure, along with serum levels of these cytokines (intermediate phenotype) and other serum biomarkers (adiponectin, leptin, CRP and HOMA-IR) in subjects with DFU. Subjects with DFU (n = 270) were genotyped by PCR-RFLP and the serum levels of IL-6, TNF-α and SDF-1 were determined by ELISA. Microbial infections were determined by standard microbiological methods. Ulcer grade and treatment procedures were recorded. IL-6 (-174G > C), TNF-α (-308G > A) and SDF-1 (+801G > A) SNPs were associated with severe microbial infections. TNF-α (-308G > A) and (-238G > A) SNPs were associated with severe ulcer grades. SDF-1 (+801G > A) SNP was associated with major amputation even after adjusting for confounding variables. Identification of these SNPs in DFU subjects would help in identifying high risk individuals who need better treatment care.


Asunto(s)
Amputación Quirúrgica , Quimiocinas/genética , Pie Diabético/genética , Pie Diabético/cirugía , Polimorfismo de Nucleótido Simple , Quimiocinas/sangre , Pie Diabético/sangre , Pie Diabético/patología , Femenino , Genotipo , Humanos , Masculino
2.
Water Sci Technol ; 75(5-6): 1118-1127, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28272040

RESUMEN

Synthetic fatliquors are useful as a fatliquoring agent, flotation agent and emulsifying agent in a wide range of industrial applications such as leather, pharmacy and farm chemicals. These fatliquors remain recalcitrant to natural biota in existing treatment plants. In the present study, the isolated microaerophilic Serratia sp. HA1 strain CSMB3 is capable of utilizing structurally different fatliquors as the sole substrate for their growth under microaerobic conditions. Degradation of vegetable fatliquors was observed from 95 to 97% in terms of lipids, with the production of lipase at 72 h. Degradation of synthetic fatliquors was observed in terms of chemical oxygen demand from 85% to a minimum of 25%. It is in the order of sulfited/sulfated fatliquors > sulfochlorinated fatliquors > chlorinated fatliquors. A thin layer chromatography chromatogram confirmed the degradation of non polar fatliquor to polar compounds. Production of the red pigment prodigiosin in synthetic fatliquors enhanced the growth of the isolate. Fourier transform infrared spectroscopy (FTIR) confirmed the bioremediation of sulfochlorinated fatliquor into lipids and fatty acids and gas chromatography-mass spectrometry (GC-MS) results confirmed that alcohols and esters are the final end products. Thus the isolated strain CSMB3 may be used in the treatment of wastewaters containing vegetable and synthetic fatliquors.


Asunto(s)
Emulsiones/metabolismo , Lípidos/química , Aerobiosis , Biodegradación Ambiental , Análisis de la Demanda Biológica de Oxígeno , Cromatografía en Capa Delgada , Cromatografía de Gases y Espectrometría de Masas , Lipasa/metabolismo , Aceites de Plantas/química , Prodigiosina/química , Serratia/crecimiento & desarrollo , Serratia/aislamiento & purificación , Serratia/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier
3.
J Theor Biol ; 420: 259-266, 2017 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-27717843

RESUMEN

Lipoic acid synthase (LIAS) is an iron-sulfur cluster mitochondrial enzyme which catalyzes the final step in the de novo pathway for the biosynthesis of lipoic acid, a potent antioxidant. Recently there has been significant interest in its role in metabolic diseases and its deficiency in LIAS expression has been linked to conditions such as diabetes, atherosclerosis and neonatal-onset epilepsy, suggesting a strong inverse correlation between LIAS reduction and disease status. In this study we use a bioinformatics approach to predict its structure, which would be helpful to understanding its role. A homology model for LIAS protein was generated using X-ray crystallographic structure of Thermosynechococcus elongatus BP-1 (PDB ID: 4U0P). The predicted structure has 93% of the residues in the most favour region of Ramachandran plot. The active site of LIAS protein was mapped and docked with S-Adenosyl Methionine (SAM) using GOLD software. The LIAS-SAM complex was further refined using molecular dynamics simulation within the subsite 1 and subsite 3 of the active site. To the best of our knowledge, this is the first study to report a reliable homology model of LIAS protein. This study will facilitate a better understanding mode of action of the enzyme-substrate complex for future studies in designing drugs that can target LIAS protein.


Asunto(s)
Modelos Moleculares , Homología de Secuencia de Aminoácido , Sulfurtransferasas/química , Dominio Catalítico , Biología Computacional/métodos , Humanos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Unión Proteica , S-Adenosilmetionina/química , Homología Estructural de Proteína , Ácido Tióctico/biosíntesis
4.
J Hazard Mater ; 321: 773-781, 2017 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-27720473

RESUMEN

Microaerobic degradation of 2-Mercaptobenzothiazole (2-MBT) was investigated using an isolated bacterial strain CSMB1. It was identified as Alcaligenes sp. MH146 by genomic analysis. The isolate degraded 50mg/L concentration of 2-MBT which was measured in terms of Total organic carbon (TOC) (700mg/L). A maximum degradation of 86% with a residual TOC concentration of 101mg/L was obtained after 72h, with the biomass growth of 290mg/L. The presence of specific activity of catechol 2, 3 oxygenase was observed in all the tested derivatives of benzothiazoles and the benzene ring opening was observed through meta cleavage. By analyzing the 72h incubated culture supernatant, 2-MBT, and all its biotransformed products were degraded into polar compounds. With the analytical results obtained, a possible microaerobic degradative pathway was proposed and illustrated for 2-MBT. It is concluded that microaerophilic isolate CSMB1 was able to degrade 2-MBT and its intermediates by utilizing them as sole carbon and energy.


Asunto(s)
Alcaligenes/metabolismo , Benzotiazoles/química , Residuos Industriales/análisis , Aguas Residuales/química , Aerobiosis , Alcaligenes/enzimología , Alcaligenes/aislamiento & purificación , Benzotiazoles/metabolismo , Biodegradación Ambiental , Biomasa , Carbono/metabolismo , Catecol 2,3-Dioxigenasa/metabolismo , Catecoles/metabolismo , Contaminantes Químicos del Agua/metabolismo
5.
Gene ; 565(1): 62-7, 2015 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-25839939

RESUMEN

The IL-6 -174G/C (rs1800795), TNF-α -308G/A (rs1800629) and -238G/A (rs361525) and SDF-1 801G/A (rs1801157) are well characterized SNPs which have previously been linked to various diabetic complications. However, the involvement of these SNPs in DFU remains poorly studied. In the present study we looked at the association of these SNPs with DFU (disease phenotype) and correlated it with the serum levels of cytokines (intermediate phenotype) along with other clinical risk factors of DFU (adiponectin, leptin and hsCRP). Genotyping was carried out in Normal glucose tolerance ((NGT)/Control=106), T2DM without DFU (T2DM=139), T2DM with neuropathy (DFU-DN=191) and T2DM with PVD (DFU-PVD=79) subjects by PCR-RFLP and the serum cytokine levels were determined by ELISA. IL-6 -176 "C" allele conferred significant protection against T2DM but not against DFU. TNF-α -308 "A" allele (but not -238 SNP) conferred significant susceptibility towards both T2DM and DFU-DN. The SDF-1 "A" allele conferred significant protection against both DM and DFU-DN but not against DFU-PVD. Further, these alleles were shown to influence the serum cytokine/chemokine levels under diabetic conditions. Thus SNPs in cytokine/chemokine genes serve as valuable biomarkers for DFU.


Asunto(s)
Quimiocina CXCL12/genética , Diabetes Mellitus Tipo 2/sangre , Pie Diabético/sangre , Interleucina-6/genética , Factor de Necrosis Tumoral alfa/genética , Adiponectina/sangre , Adulto , Proteína C-Reactiva/metabolismo , Quimiocina CXCL12/sangre , Diabetes Mellitus Tipo 2/genética , Pie Diabético/genética , Femenino , Estudios de Asociación Genética , Humanos , Interleucina-6/sangre , Leptina/sangre , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Factor de Necrosis Tumoral alfa/sangre
6.
J Mater Sci Mater Med ; 26(1): 5378, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25601669

RESUMEN

Monodispersed lanthanum hydroxide nano-rods (LaNRs) were synthesized for prospective biomedical application using a microwave heating and ultrasonic agitation methodology which does not require any toxic stabilizing agent. The average length and diameter of the LaNRs thus obtained were 183.4 ± 3.6 and 9.9 ± 0.2 nm respectively, as analyzed by HRTEM. FTIR spectrum confirmed the presence of OH groups. The thermal transformation of lanthanum hydroxide (La(OH)3) was studied by thermogravimetric analysis. The synthesized LaNRs were found to be stable for a period of 1 month at room temperature. They were biocompatible as evaluated by haemocompatibility assay and viability assay using human peripheral blood mononuclear cells. The pro-angiogenic property of LaNRs was demonstrated by in vivo chick chorioallantoic membrane assay. The LaNRs induced osteoblast differentiation of human adipose derived stem cells with significant calcium (Ca(2+)) deposition indicating potential applications in bone tissue engineering.


Asunto(s)
Materiales Biocompatibles/química , Lantano/química , Nanotubos , Tejido Adiposo/patología , Adsorción , Animales , Calcio/química , Bovinos , Diferenciación Celular , Supervivencia Celular , Embrión de Pollo , Membrana Corioalantoides/metabolismo , Humanos , Hidróxidos/química , Iones , Leucocitos Mononucleares/citología , Osteoblastos/citología , Estudios Prospectivos , Espectroscopía Infrarroja por Transformada de Fourier , Células Madre/citología , Temperatura , Termogravimetría , Ingeniería de Tejidos/métodos , Ultrasonido
7.
Biometals ; 28(1): 21-33, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25326906

RESUMEN

Environmental exposure of Cr(VI) and Ni(II) due to rapid industrialization causes adverse effects in living tissues. Small quantities of these ions also find their way into tissues when metal alloys are used as implants. Even though considerable research has been done on the effects due to their exposure in animal cells, there are only very few reports on how they can affect stem cells which have been shown to be found in adult tissues as well, albeit in small quantities. Hence this study was aimed at understanding how Cr(VI) and Ni(II) affect human adipose derived stem cells (hADSCs) in a cell culture environment. Our results indicate that both ions induce apoptosis in a concentration and time dependent manner with loss of mitochondrial membrane potential (MMP) and corresponding increase in caspase-3 activity. With regard to Ni(II), apoptosis seems to occur only in a small percentage of cells while necrosis is predominant. It can be inferred that the long term exposure of these metals may cause adverse effects in stem cell proliferation and differentiation.


Asunto(s)
Adipocitos/citología , Adipocitos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Cromo/farmacología , Níquel/farmacología , Caspasa 3/metabolismo , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Humanos , Células Madre/efectos de los fármacos
8.
Chem Biol Interact ; 224: 78-88, 2014 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-25446498

RESUMEN

There is significant interest in investigating the therapeutic potential of phytochemical reduced and bound gold nanoparticles (AuNPs) as it bridges the gap between nanotechnology and therapy. In the present study, AuNPs prepared using the flavonoid morin (mAuNPs) are characterised and have been studied for their anti-cancer effects. The -OH groups of morin reduce Au(3+) and stabilize Au(0) to form spherical and crystalline mAuNPs. These mAuNPs are biocompatible towards normal human blood cells and breast epithelial cells. Through TEM analysis, we report that they are readily taken up by breast cancer cells (MCF-7) to induce cell death. Apoptosis has also been assessed by other morphological observations and cell viability studies. Flow cytometric studies reveal that the cells undergo a transient phase of apoptosis progressing towards secondary necrosis as the dose and time of mAuNPs treatment increases. The ability of mAuNPs to induce cell death in MCF-7 cells indicates its potential as an anti-cancer agent.


Asunto(s)
Antineoplásicos/farmacología , Flavonoides/farmacología , Oro/química , Nanopartículas del Metal/química , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/toxicidad , Apoptosis/efectos de los fármacos , Materiales Biocompatibles/administración & dosificación , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/toxicidad , Eritrocitos/citología , Eritrocitos/efectos de los fármacos , Flavonoides/administración & dosificación , Flavonoides/química , Flavonoides/toxicidad , Puntos de Control de la Fase G2 del Ciclo Celular , Humanos , Lisosomas/metabolismo , Células MCF-7 , Nanopartículas del Metal/administración & dosificación , Nanopartículas del Metal/toxicidad
9.
Eur J Med Chem ; 63: 474-83, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23524113

RESUMEN

Marine organisms provide several biologically active compounds that include alkaloids with high cytotoxic activity but only a few of them have so far reached clinical stage, due partly to their limited supply and complex structural features. In an attempt to develop novel anticancer compounds, we have now synthesized diaminoindoloylthiazoles (4a-c; DIT1-3) and diaminocinnamoylthiazoles (5a,b; DCT1-2) as analogs based on a topsentin scaffold and investigated the cytotoxic and apoptotic activities of these compounds in HeLa cells. The results suggest that diaminoindoloylthiazoles (DIT1-3) inhibit cell growth and among these, DIT3 is the most cytotoxic against HeLa cells (IC50 1 µM). The diaminocinnamoylthiazoles DCT1 and DCT2, which can be viewed as curcumin-diaminothiazole hybrids, also inhibited cell growth but at relatively higher concentrations with IC50 values of 60 and 30 µM, respectively. These compounds induced apoptosis through the intrinsic pathway by reducing the mitochondrial membrane potential and activating caspases, 9 and 3, but not caspase 8. Among the marine alkaloid analogs tested in this study, DIT1-3 are very effective in inducing apoptosis of HeLa cells followed by DCT2 and DCT1. The treated cells were arrested in G2/M phase followed by accumulation of the cells in the Sub G0 phase. The curcumin-diaminothiazole hybrid DCT1 had the maximum effect in downregulating TNF-induced NF-κB activation among the compounds tested in this study. Thus, we demonstrate that diaminoindoloylthiazoles and diaminocinnamoylthiazoles induce apoptosis, regulate cell cycle and NF-κB signaling and thus show promising anticancer effects that warrant further investigation.


Asunto(s)
Alcaloides/síntesis química , Apoptosis/fisiología , Imidazoles/síntesis química , Indoles/síntesis química , Tiazoles/síntesis química , Alcaloides/química , Alcaloides/farmacología , Animales , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Proliferación Celular/efectos de los fármacos , Cinamatos/síntesis química , Cinamatos/química , Cinamatos/farmacología , Relación Dosis-Respuesta a Droga , Activación Enzimática/efectos de los fármacos , Citometría de Flujo , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Células HeLa , Humanos , Imidazoles/química , Imidazoles/farmacología , Indoles/química , Indoles/farmacología , Concentración 50 Inhibidora , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Modelos Químicos , Estructura Molecular , FN-kappa B/metabolismo , Poríferos/química , Agua de Mar/parasitología , Transducción de Señal/efectos de los fármacos , Tiazoles/química , Tiazoles/farmacología , Factor de Necrosis Tumoral alfa/farmacología
10.
Artículo en Inglés | MEDLINE | ID: mdl-23380147

RESUMEN

The present study focuses on the rapid synthesis of gold nanoparticles (AuNP) using the aqueous extract of Cissus quadrangularis (CQE) by microwave irradiation. The UV-Visible spectroscopy of the solution obtained from reduction of hydrogen tetrachloroaurate (HAuCl4) by CQE revealed a sharp surface plasmon resonance (SPR) peak at 530 nm confirming the presence of AuNP. The formation of AuNP was optimal at a pH of 9. The AuNP was characterised by FT-IR, SEM, HR-TEM, SAED, XRD, TGA, DLS and Zeta potential measurements. The results indicated that microwave assisted synthesis produced well dispersed, small sized, uniform nanoparticles when compared to conventional room temperature synthesis. The spherical nanoparticle had an average size of 12.0±3.2 nm as revealed through TEM. The crystalline nature of AuNP was confirmed through HR-TEM, SAED and XRD. The FT-IR and TGA data revealed the presence of the CQE components on the surface of the AuNP particles which serve as the capping agent. Upon incubation, the particles did not lyse the red blood corpuscles (RBCs) indicating that they are biocompatible. A possible mechanism for the formation of AuNP in the presence of CQE is proposed.


Asunto(s)
Cissus/química , Oro/química , Nanopartículas del Metal/química , Microondas , Extractos Vegetales/química , Materiales Biocompatibles/química , Eritrocitos/efectos de los fármacos , Hemólisis/efectos de los fármacos , Nanopartículas del Metal/ultraestructura , Nanotecnología/economía , Nanotecnología/métodos , Análisis Espectral , Factores de Tiempo
11.
Int J Pharm ; 438(1-2): 117-22, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-22960320

RESUMEN

Electrospun composite zein/eudragit nanofibers were developed with an aim to deliver two different classes of drugs simultaneously that would restrict/compensate the adverse effects of non-steroidal anti-inflammatory drugs (NSAIDs). Co-administration of proton pump inhibitors is beneficial for patients consuming NSAIDs for treating chronic ailments like arthritis. In this study, aceclofenac/pantoprazole loaded zein/eudragit S 100 nanofibers were developed using a single nozzle electrospinning process. The morphological analysis revealed the uniform and smooth surface of the drug loaded nanofibers. The physico-thermal characterization of nanofibers depicted the molecular integration of the drugs with the polymers and also confirmed that the drugs were evenly distributed in the nanofibers in an amorphous state. In vitro release studies ensure the efficiency of the developed fibers in sustaining the release of both the drugs up to 8h. In vivo animal experiments further confirmed that the co-administration of pantoprazole along with aceclofenac reduced the gastro-intestinal toxicity induced by NSAIDs. The histological evaluation revealed the preserved mucosal architecture of rat gastric tissue treated with drug loaded composite nanofibers. Thus, dual drug delivery system comprising polymers with different release characteristics has been successfully developed and further, oral delivery of aceclofenac with reduced side effects was achieved.


Asunto(s)
2-Piridinilmetilsulfinilbencimidazoles/administración & dosificación , Antiinflamatorios no Esteroideos/administración & dosificación , Diclofenaco/análogos & derivados , Portadores de Fármacos/administración & dosificación , Nanofibras/administración & dosificación , Inhibidores de la Bomba de Protones/administración & dosificación , Animales , Diclofenaco/administración & dosificación , Portadores de Fármacos/química , Combinación de Medicamentos , Composición de Medicamentos/métodos , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/patología , Nanofibras/química , Pantoprazol , Ácidos Polimetacrílicos/química , Ratas , Ratas Wistar , Zeína/química
12.
Transl Res ; 159(3): 182-9, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22340768

RESUMEN

Keloids are manifestations of abnormal wound repair with unresolved clinical complications. An effective therapeutic regimen has not been established for keloids, and current strategies are plagued by problems such as recurrence and side effects. Keloids, being a human-specific dermal fibroproliferative disorder are characterized by an excessive accumulation of extracellular matrix (ECM), thickened basement membrane, unregulated expression of matrix metalloproteases, growth factors, and cytokines. The internal milieu in a keloid bears a strong resemblance to a tumor with both exhibiting striking similarities with respect to tissue environment and unregulated vasculature. Abnormal angiogenesis manifested by an imbalance between proangiogenic and antiangiogenic factors has been recognized as a "common denominator" underlying many pathological conditions. However, such an imbalance has not been investigated in keloids. In this study, the angiogenic imbalance in keloids was explored with reference to circulating and tissue level expression of vascular endothelial growth factor (VEGF) and endostatin/collagen XVIII. It was observed that VEGF levels were upregulated and endostatin levels were downregulated in keloid patients in comparison to normal controls in both sera and tissue. Hence, antiangiogenic therapeutics based on endostatin in combination with current curative strategies as in tumors would present a scope for the effective management of keloids.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Endostatinas/metabolismo , Endostatinas/uso terapéutico , Queloide/tratamiento farmacológico , Queloide/metabolismo , Neovascularización Patológica/tratamiento farmacológico , Neovascularización Patológica/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Adolescente , Adulto , Anciano , Animales , Estudios de Casos y Controles , Niño , Colágeno Tipo XVIII/metabolismo , Terapia Combinada , Regulación hacia Abajo , Endostatinas/sangre , Endostatinas/genética , Matriz Extracelular/metabolismo , Femenino , Humanos , Queloide/patología , Linfocinas/metabolismo , Masculino , Ratones , Ratones Noqueados , Persona de Mediana Edad , Neovascularización Patológica/patología , Regulación hacia Arriba , Factor A de Crecimiento Endotelial Vascular/sangre , Factor A de Crecimiento Endotelial Vascular/genética
13.
AAPS PharmSciTech ; 13(1): 143-9, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22167417

RESUMEN

Nonsteroidal anti-inflammatory drugs (NSAIDs) induce gastric injury on long-term usage. This study aims at reducing the side effect of NSAIDs by encapsulating in zein, an acid-resistant biopolymer. Aceclofenac-loaded zein microspheres were prepared by emulsification and solvent evaporation method. The stability of zein microspheres at gastric pH retarded the release of the entrapped drug and hence reduces the possibility of gastric injury. However, the in vitro release of aceclofenac was sustained up to 72 h at intestinal pH. Thus, zein microspheres pave the way for the development of safe and sustained delivery system for NSAIDs thereby achieving the desired therapeutic potential with reduced side effects for chronic inflammatory disorders.


Asunto(s)
Antiinflamatorios no Esteroideos/administración & dosificación , Diclofenaco/análogos & derivados , Portadores de Fármacos/administración & dosificación , Sistemas de Liberación de Medicamentos/métodos , Microesferas , Zeína/administración & dosificación , Animales , Antiinflamatorios no Esteroideos/síntesis química , Antiinflamatorios no Esteroideos/metabolismo , Células Cultivadas , Preparaciones de Acción Retardada , Diclofenaco/administración & dosificación , Diclofenaco/síntesis química , Diclofenaco/metabolismo , Portadores de Fármacos/síntesis química , Portadores de Fármacos/metabolismo , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Zeína/síntesis química , Zeína/metabolismo
14.
Free Radic Biol Med ; 51(11): 2090-107, 2011 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-21982843

RESUMEN

The phytochemicals plumbagin and juglone have recently been gaining importance because of their various pharmacological activities. In this study, these compounds are shown to induce concentration- and time-dependent toxicity in human peripheral blood lymphocytes via the apoptotic pathway. Flow cytometry data revealed the occurrence of about 28% early apoptotic cells after 6h exposure to 10µM plumbagin and 35% late apoptotic cells and about 43% sub-G1 population after 24h. The cytotoxic effect of plumbagin was at least twofold higher than that of juglone as evidenced by the IC(50) value for cytotoxicity. Characteristic apoptotic features such as chromatin condensation and apoptotic body formation were observed through TEM, and membrane blebbing and cell surface smoothening were seen in SEM studies. Generation of ROS was evidenced through the HPLC analysis of superoxide-specific 2-OH-E+ formation. In addition, a decrease in GSH levels parallel to ROS production was observed. Reversal of apoptosis in both NAC- and Tempol-pretreated cells indicates the involvement of both ROS generation and GSH depletion in plumbagin- and juglone-induced apoptosis. The mechanistic pathway involves a decrease in MMP; alterations in the levels of Bcl-2, Bax, and cytosolic cytochrome c; and PARP-1 cleavage subsequent to caspase-3 activation.


Asunto(s)
Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Leucocitos Mononucleares/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Naftoquinonas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Adulto , Inhibidores de Caspasas , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/metabolismo , Mitocondrias/metabolismo , Naftoquinonas/química , Oligopéptidos/farmacología , Valores de Referencia , Factores de Tiempo
15.
J Biomed Nanotechnol ; 7(1): 56, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21485801

RESUMEN

The use of nano-particles in several areas necessitates the understanding of their interaction with cells, tissues and experimental animals. In the present study, the effect of a curcumin conjugated gold nano-particle on peripheral blood lymphocytes was investigated. The treated lymphocytes revealed features typical of apoptosis which include chromatin condensation, and membrane blebbing and occurrence of apoptotic bodies. The observations indicate that these nanoparticle conjugates may find use as drugs in non-toxic range observed in cytotoxicity studies.


Asunto(s)
Curcumina/administración & dosificación , Oro/efectos adversos , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/efectos de los fármacos , Nanocápsulas/efectos adversos , Nanocápsulas/química , Nanopartículas/efectos adversos , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/efectos adversos , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Curcumina/química , Relación Dosis-Respuesta a Droga , Oro/química , Humanos , Nanopartículas/química
16.
Lipids Health Dis ; 9: 74, 2010 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-20637131

RESUMEN

BACKGROUND: Frog skin has been sequentially and scientifically evaluated by our group for its wound healing efficiency. Owing to the complex structure of skin, attempts were being made to analyse the role of individual constituents in different phases of healing. Our earlier papers have shown the significance of frog skin not only in wound healing but also enhancing the proliferating activity of the epidermal and dermal cells which are instrumental for normal healing process. We also have identified for the first time novel antimicrobial peptides from the skin of Rana tigerina and thereby reduce the complications involved in the sepsis. PURPOSE OF THE STUDY AND RESULTS: The current study envisages the role of frog skin lipids in the inflammatory phase of wound healing. The lipid moiety of the frog skin dominated by phospholipids exhibited a dose dependent acceleration of healing irrespective of the mode of application. The efficiency of the extract is attributed partially to the anti-inflammatory activity as observed by the histochemical and immunostimulatory together with plethysmographic studies. CONCLUSIONS: Thus, frog skin for the first time has been demonstrated to possess lipid components with pharmaceutical and therapeutic potential. The identification and characterization of such natural healing molecules and evaluating their mechanism of action would therefore provide basis for understanding the cues of Nature and hence can be used for application in medicine.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Lípidos/uso terapéutico , Materia Medica , Ranidae , Piel/química , Piel/efectos de los fármacos , Extractos de Tejidos/uso terapéutico , Cicatrización de Heridas/efectos de los fármacos , Administración Cutánea , Animales , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/análisis , Antiinflamatorios no Esteroideos/inmunología , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Edema/inducido químicamente , Edema/tratamiento farmacológico , Femenino , Tejido de Granulación/química , Tejido de Granulación/efectos de los fármacos , Hipersensibilidad/tratamiento farmacológico , Hipersensibilidad/inmunología , Inmunidad Humoral/efectos de los fármacos , India , Inyecciones Intraperitoneales , Lípidos/administración & dosificación , Lípidos/análisis , Lípidos/inmunología , Medicina Tradicional , Ratas , Ratas Wistar , Piel/lesiones , Extractos de Tejidos/administración & dosificación , Extractos de Tejidos/química , Extractos de Tejidos/inmunología
17.
Toxicol Appl Pharmacol ; 243(3): 405-19, 2010 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-20043934

RESUMEN

We have studied the effect of Cr(III)(phen)3 [(tris(1,10-phenanthroline) chromium(III) chloride)] on lymphocytes in order to find out if metallothioneins (MTs) are produced in the process. We also investigated whether zinc pretreatment is able to protect cells from apoptosis reported to occur for this compound. Our results indicate that MT synthesis is induced by Cr(III)(phen)3, and it has been identified as the MT-3 isoform through RT-PCR which has not been reported earlier. By zinc pretreatment, this apoptosis is reversed as inferred from cytotoxicity studies, Annexin-V/PI staining, ethidium bromide/acridine orange staining and DNA fragmentation pattern and ultrastructural investigations using TEM and SEM. The zinc pretreatment reduces the amount of ROS produced by Cr(III)(phen)3. The MT-1a and 1b synthesized by zinc (also evidenced through RT-PCR experiments) is possibly able to scavenge ROS which is one of the early signaling molecules that lead to apoptosis. Zinc pretreatment also reverses the changes in downstream signaling events such as mitochondrial membrane potential, ATP levels and the activation of caspase-3. This is the first report on the induction of MT-3 in lymphocytes due to a metal stress or any other stimuli. Even though MT-3 is synthesized here, apoptosis still occurs due to ROS production on Cr(III)(phen)3 exposure when the cells have not been primed with zinc.


Asunto(s)
Apoptosis/efectos de los fármacos , Linfocitos/efectos de los fármacos , Compuestos Organometálicos/antagonistas & inhibidores , Compuestos Organometálicos/toxicidad , Sustancias Protectoras , Compuestos de Zinc/farmacología , Adenosina Trifosfato/metabolismo , Caspasa 3/metabolismo , Catalasa/metabolismo , Separación Celular , Supervivencia Celular/efectos de los fármacos , Cromo/metabolismo , Cisteína/metabolismo , ADN/biosíntesis , ADN/genética , Fragmentación del ADN/efectos de los fármacos , Electroforesis en Gel de Agar , Humanos , Ligandos , Linfocitos/metabolismo , Linfocitos/ultraestructura , Metalotioneína/metabolismo , Microscopía Electrónica de Transmisión , Membranas Mitocondriales/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Tinción con Nitrato de Plata , Superóxido Dismutasa/metabolismo , Timidina/metabolismo , Compuestos de Zinc/metabolismo
18.
Toxicol In Vitro ; 24(2): 586-96, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19853652

RESUMEN

In recent times, Cr(III)(picolinate)(3) [Cr(III)(pic)(3)] a nutritional supplement, is gaining attention because of its clastogenic and mutagenic properties. Earlier studies of ours indicated that Cr(III)(pic)(3) is cytotoxic to lymphocytes with ROS and mitochondrial events playing a role in bringing about apoptosis. Now, we report that, autoschizis is induced in lymphocytes in a concentration and time dependent manner which is confirmed through TEM and SEM. Lymphocytes treated with concentrations of 100microM of Cr(III)(pic)(3) exhibit features such as cytoplasmic bleb, self excision of cytoplasm, cytoplasmic leakage and membrane bound bodies formed from the excised pieces apart from apoptosis and necrosis. Though autoschizis has been described in tumor cell lines treated with menadione and ascorbate, occurrence of this cell death in normal T-lymphocytes is reported here. The cellular events that accompany autoschizis are found to be increase in intracellular Reactive Oxygen Species (ROS) and cytoplasmic lactate dehydrogenase, loss of mitochondrial membrane potential (MMP) and depletion of ATP. Further, autoschizis is effected through increases in DNase I and DNase II activity with a concomitant decrease in caspase-3 activity which leads to a random cleavage of the DNA as demonstrated by a smear like pattern after electrophoresis on agarose gel.


Asunto(s)
Muerte Celular/efectos de los fármacos , Quelantes del Hierro/toxicidad , Leucocitos Mononucleares/efectos de los fármacos , Ácidos Picolínicos/toxicidad , Caspasa 3/genética , Caspasa 3/metabolismo , Supervivencia Celular/efectos de los fármacos , ADN/química , Desoxirribonucleasa I/metabolismo , Suplementos Dietéticos/efectos adversos , Relación Dosis-Respuesta a Droga , Endodesoxirribonucleasas/metabolismo , Regulación Enzimológica de la Expresión Génica , Humanos
19.
Toxicol Appl Pharmacol ; 237(3): 331-44, 2009 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-19376147

RESUMEN

Cr(III)(picolinate)(3) [Cr(III)(pic)(3)] is currently used as a nutritional supplement and for treating Type-2 diabetes. The effect of Cr(III)(pic)(3) uptake in peripheral blood lymphocytes is investigated in this study. From the cytotoxicity data, DNA fragmentation pattern, Annexin V staining, TUNEL positivity and the ultrastructural characteristics such as chromatin condensation and formation of apoptotic bodies, it is clear that Cr(III)(pic)(3) induces a concentration dependent apoptosis. It is shown that reactive oxygen species (ROS) produced by treatment with Cr(III)(pic)(3) leads to apoptosis, since we find that pretreatment with N-acetyl cysteine inhibits the process. Using Western blotting technique and fluorescence measurements, the downstream signaling molecules have also been identified. Cr(III)(pic)(3) treatment leads to collapse of the mitochondrial membrane potential, Bax expression, increase in cytosolic cytochrome c content and active caspase-3 and DNA fragmentation and all these manifestations are reduced by pretreating the lymphocytes with N-acetyl cysteine. Thus, it is shown that Cr(III)(pic)(3) is cytotoxic to lymphocytes with ROS and mitochondrial events playing a role in bringing about apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Linfocitos/efectos de los fármacos , Ácidos Picolínicos/toxicidad , Transducción de Señal/efectos de los fármacos , Apoptosis/inmunología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/inmunología , Células Cultivadas , Humanos , Linfocitos/metabolismo , Linfocitos/patología , Ácidos Picolínicos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Especies Reactivas de Oxígeno/toxicidad , Transducción de Señal/inmunología
20.
EMBO J ; 26(4): 1035-44, 2007 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-17290228

RESUMEN

Copper is an essential but potentially toxic trace element. In Drosophila, the metal-responsive transcription factor (MTF-1) plays a dual role in copper homeostasis: at limiting copper concentrations, it induces the Ctr1B copper importer gene, whereas at high copper concentrations, it mainly induces the metallothionein genes. Here we find that, despite the downregulation of the Ctr1B gene at high copper concentrations, the protein persists on the plasma membrane of intestinal cells for many hours and thereby fills the intracellular copper stores. Drosophila may risk excessive copper accumulation for the potential benefit of overcoming a period of copper scarcity. Indeed, we find that copper-enriched flies donate a vital supply to their offspring, allowing the following generation to thrive on low-copper food. We also describe two additional modes of copper handling: behavioral avoidance of food containing high (>or=0.5 mM) copper levels, as well as the ability of DmATP7, the Drosophila homolog of Wilson/Menkes disease copper exporters, to counteract copper toxicity. Regulated import, storage, export, and avoidance of high-copper food establish an adequate copper homeostasis under variable environmental conditions.


Asunto(s)
Proteínas de Transporte de Catión/metabolismo , Cobre/metabolismo , Proteínas de Unión al ADN/metabolismo , Drosophila/metabolismo , Regulación de la Expresión Génica , Homeostasis/fisiología , Factores de Transcripción/metabolismo , Animales , Western Blotting , ATPasas Transportadoras de Cobre , Drosophila/fisiología , Conducta Alimentaria/fisiología , Mucosa Intestinal/metabolismo , Metalotioneína/metabolismo , Microscopía Fluorescente , Factor de Transcripción MTF-1
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