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1.
Proc Natl Acad Sci U S A ; 121(20): e2402180121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38717859

RESUMO

Membrane tubulation coupled with fission (MTCF) is a widespread phenomenon but mechanisms for their coordination remain unclear, partly because of the lack of assays to monitor dynamics of membrane tubulation and subsequent fission. Using polymer cushioned bilayer islands, we analyze the membrane tubulator Bridging Integrator 1 (BIN1) mixed with the fission catalyst dynamin2 (Dyn2). Our results reveal this mixture to constitute a minimal two-component module that demonstrates MTCF. MTCF is an emergent property and arises because BIN1 facilitates recruitment but inhibits membrane binding of Dyn2 in a dose-dependent manner. MTCF is therefore apparent only at high Dyn2 to BIN1 ratios. Because of their mutual involvement in T-tubules biogenesis, mutations in BIN1 and Dyn2 are associated with centronuclear myopathies and our analysis links the pathology with aberrant MTCF. Together, our results establish cushioned bilayer islands as a facile template for the analysis of membrane tubulation and inform of mechanisms that coordinate MTCF.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Dinamina II , Proteínas Supressoras de Tumor , Dinamina II/metabolismo , Dinamina II/genética , Humanos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Supressoras de Tumor/metabolismo , Proteínas Supressoras de Tumor/genética , Membrana Celular/metabolismo , Proteínas Nucleares/metabolismo , Proteínas Nucleares/genética , Dinâmica Mitocondrial/fisiologia , Miopatias Congênitas Estruturais/genética , Miopatias Congênitas Estruturais/metabolismo
2.
Proc Natl Acad Sci U S A ; 120(11): e2215250120, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36888655

RESUMO

Classical dynamins are best understood for their ability to generate vesicles by membrane fission. During clathrin-mediated endocytosis (CME), dynamin is recruited to the membrane through multivalent protein and lipid interactions between its proline-rich domain (PRD) with SRC Homology 3 (SH3) domains in endocytic proteins and its pleckstrin-homology domain (PHD) with membrane lipids. Variable loops (VL) in the PHD bind lipids and partially insert into the membrane thereby anchoring the PHD to the membrane. Recent molecular dynamics (MD) simulations reveal a novel VL4 that interacts with the membrane. Importantly, a missense mutation that reduces VL4 hydrophobicity is linked to an autosomal dominant form of Charcot-Marie-Tooth (CMT) neuropathy. We analyzed the orientation and function of the VL4 to mechanistically link data from simulations with the CMT neuropathy. Structural modeling of PHDs in the cryo-electron microscopy (cryo-EM) cryoEM map of the membrane-bound dynamin polymer confirms VL4 as a membrane-interacting loop. In assays that rely solely on lipid-based membrane recruitment, VL4 mutants with reduced hydrophobicity showed an acute membrane curvature-dependent binding and a catalytic defect in fission. Remarkably, in assays that mimic a physiological multivalent lipid- and protein-based recruitment, VL4 mutants were completely defective in fission across a range of membrane curvatures. Importantly, expression of these mutants in cells inhibited CME, consistent with the autosomal dominant phenotype associated with the CMT neuropathy. Together, our results emphasize the significance of finely tuned lipid and protein interactions for efficient dynamin function.


Assuntos
Proteínas Sanguíneas , Dinaminas , Microscopia Crioeletrônica , Dinaminas/metabolismo , Endocitose/fisiologia , Lipídeos , Dinamina I/metabolismo
3.
Homeopathy ; 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37748512

RESUMO

INTRODUCTION: This study aimed at examining the feasibility issues of comparing individualized homeopathic medicines (IHMs) with identical-looking placebos for treating knee osteoarthritis (OA). METHODS: Forty eligible patients participated in this double-blind, randomized (1:1), placebo-controlled feasibility trial in the outpatient clinics of a homeopathic hospital in West Bengal, India. Either IHMs or identical-looking placebos were administered, along with mutually agreed-upon concomitant care guidelines. The Knee Injury and Osteoarthritis Outcome Score (KOOS) was the primary outcome measure, and derived Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores from KOOS, EQ-5D-5L questionnaire, and Visual Analog Scale (VAS) were the secondary outcomes; all measured at baseline and after 2 months. Group differences and effect sizes (Cohen's d) were estimated using an intention-to-treat approach. p-Values less than 0.05 (two-tailed) were considered statistically significant. RESULTS: Enrolment/screening and trial retention rates were 43% and 85% respectively. Recruitment was difficult owing to the coronavirus disease 2019 (COVID-19) lockdown. Group differences were statistically significant, favoring IHMs against placebos in all the KOOS sub-scales: symptoms (p < 0.001), pain (p = 0.002), activities of daily living (p < 0.001), sports or recreation (p = 0.016), and quality of life (p = 0.002). Derived WOMAC scores from KOOS favored IHMs against placebos: stiffness (p < 0.001) and pain (p < 0.001). The EQ-5D-5L questionnaire score (p < 0.001) and EQ-5D-5L VAS scores (p < 0.001) also yielded significant results, favoring IHMs over placebos. All the effect sizes ranged from moderate to large. Sulphur was the most frequently prescribed homeopathic medication. Neither group reported any harm or serious adverse events. CONCLUSION: Although recruitment was sub-optimal due to prevailing COVID-19 conditions during the trial, the action of IHMs was found to be superior to that of placebos in the treatment of knee OA. Larger and more definitive studies, with independent replications, are required to substantiate the findings. TRIAL REGISTRATION: CTRI/2021/02/031453.

4.
Traffic ; 21(3): 297-305, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31846132

RESUMO

Soluble proteins that bind membranes function in numerous cellular pathways yet facile, sensitive and quantitative methods that complement and improve sensitivity of widely used liposomes-based assays remain unavailable. Here, we describe the utility of a photoactivable fluorescent lipid as a generic reporter of protein-membrane interactions. When incorporated into liposomes and exposed to ultraviolet (UV), proteins bound to liposomes become crosslinked with the fluorescent lipid and can be readily detected and quantitated by in-gel fluorescence analysis. This modification obviates the requirement for high-speed centrifugation spins common to most liposome-binding assays. We refer to this assay as Proximity-based Labeling of Membrane-Associated Proteins (PLiMAP).


Assuntos
Lipídeos , Lipossomos , Proteínas de Membrana , Membranas
5.
Homeopathy ; 111(2): 97-104, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34715718

RESUMO

INTRODUCTION: There is some evidence that homeopathic treatment has been used successfully in previous epidemics, and currently some countries are testing homeoprophylaxis for the coronavirus disease 2019 (COVID-19) pandemic. There is a strong tradition of homeopathic treatment in India: therefore, we decided to compare three different homeopathic medicines against placebo in prevention of COVID-19 infections. METHODS: In this double-blind, cluster-randomized, placebo-controlled, four parallel arms, community-based, clinical trial, a 20,000-person sample of the population residing in Ward Number 57 of the Tangra area, Kolkata, was randomized in a 1:1:1:1 ratio of clusters to receive one of three homeopathic medicines (Bryonia alba 30cH, Gelsemium sempervirens 30cH, Phosphorus 30cH) or identical-looking placebo, for 3 (children) or 6 (adults) days. All the participants, who were aged 5 to 75 years, received ascorbic acid (vitamin C) tablets of 500 mg, once per day for 6 days. In addition, instructions on healthy diet and general hygienic measures, including hand washing, social distancing and proper use of mask and gloves, were given to all the participants. RESULTS: No new confirmed COVID-19 cases were diagnosed in the target population during the follow-up timeframe of 1 month-December 20, 2020 to January 19, 2021-thus making the trial inconclusive. The Phosphorus group had the least exposure to COVID-19 compared with the other groups. In comparison with placebo, the occurrence of unconfirmed COVID-19 cases was significantly less in the Phosphorus group (week 1: odds ratio [OR], 0.1; 95% confidence interval [CI], 0.06 to 0.16; week 2: OR, 0.004; 95% CI, 0.0002 to 0.06; week 3: OR, 0.007; 95% CI, 0.0004 to 0.11; week 4: OR, 0.009; 95% CI, 0.0006 to 0.14), but not in the Bryonia or Gelsemium groups. CONCLUSION: Overall, the trial was inconclusive. The possible effect exerted by Phosphorus necessitates further investigation. TRIAL REGISTRATION: CTRI/2020/11/029265.


Assuntos
Bryonia , Tratamento Farmacológico da COVID-19 , COVID-19 , Gelsemium , Homeopatia , Materia Medica , Adulto , COVID-19/prevenção & controle , Criança , Método Duplo-Cego , Humanos , Materia Medica/uso terapêutico , Pandemias/prevenção & controle , Fósforo , SARS-CoV-2 , Resultado do Tratamento
6.
Environ Monit Assess ; 194(4): 276, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35286502

RESUMO

Kolkata being a metropolitan city in India has its main municipal solid waste dumpsite situated at Dhapa just adjacent to the East Kolkata Wetlands (Ramsar site). The current prevalent situation at Dhapa is open dumping leading to various contaminations and hazards putting forth the need to look for alternative sites where the landfiilling operation can be shifted to using scientific methods. A user interface (UI)-based analytical hierarchy process (AHP) tool has been developed within the Google Earth Engine (GEE) cloud platform to find out the alternative dumping sites using geospatial layers. AHP function is not available as a native algorithm or developed by any researcher in GEE. The tool has three major functionalities, of which the first one handles the UI elements. The AHP procedure is within another function, and the last function integrates the AHP coefficients to the layers generating the final suitability layer. Users can also upload comparison matrix as GEE asset in the form of CSV file which gets automatically integrated into the AHP to calculate the coefficients and consistency ratio to generate the spatial suitability layers. This approach showcases a generalized AHP function within the GEE environment, which has been done for the first time. The tool is designed in the cloud platform which is dynamic, robust and suitable for use in various AHP-based suitability analysis in environmental monitoring and assessment.


Assuntos
Eliminação de Resíduos , Processo de Hierarquia Analítica , Monitoramento Ambiental/métodos , Sistemas de Informação Geográfica , Eliminação de Resíduos/métodos , Ferramenta de Busca , Instalações de Eliminação de Resíduos
7.
Phys Rev Lett ; 126(6): 061302, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33635718

RESUMO

Flavor-dependent neutrino emission is critical to the evolution of a supernova and its neutrino signal. In the dense anisotropic interior of the star, neutrino-neutrino forward scattering can lead to fast collective neutrino oscillations, which has striking consequences. We present a theory of fast flavor depolarization, explaining how neutrino flavor differences become smaller, i.e., depolarize, due to diffusion to smaller angular scales. We show that transverse relaxation determines the epoch of this irreversible depolarization. We give a method to compute the depolarized fluxes, presenting an explicit formula for simple initial conditions, which can be a crucial input for supernova theory and neutrino phenomenology.

8.
Biochemistry ; 58(1): 65-71, 2019 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-30403133

RESUMO

Membrane fission manifests during cell division, synaptic transmission, vesicular transport, and organelle biogenesis, yet identifying proteins that catalyze fission remains a challenge. Using a facile and robust assay system of supported membrane tubes in a microscopic screen that directly monitors membrane tube scission, we detect robust GTP- and ATP-dependent as well as nucleotide-independent fission activity in the brain cytosol. Using previously established interacting partner proteins as bait for pulldowns, we attribute the GTP-dependent fission activity to dynamin. Biochemical fractionation followed by mass spectrometric analyses identifies the Eps15-homology domain-containing protein1 (EHD1) as a novel ATP-dependent membrane fission catalyst. Together, our approach establishes an experimental workflow for the discovery of novel membrane fission catalysts.


Assuntos
Encéfalo/metabolismo , Membrana Celular/química , Membrana Celular/metabolismo , Citosol/metabolismo , Dinaminas/metabolismo , Guanosina Trifosfato/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animais , Transporte Biológico , Cabras , Ensaios de Triagem em Larga Escala , Humanos
9.
Toxicol Ind Health ; 34(12): 908-921, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30317941

RESUMO

BACKGROUND: Despite the available clinico-epidemiological evidence of heavy metal-associated respiratory health hazards among metal arc-welders, experimental confirmation of such an association is lacking. METHODS: In this study, we recruited 15 metal arc-welders and 10 referent workers without direct exposure. We assessed respiratory health through a questionnaire and spirometry; estimated manganese, nickel and cadmium levels in blood, urine and induced sputum; performed differential counts of sputum leucocytes and measured plasma malondialdehyde (MDA). We used atomic force and scanning electron microscopy to assess the physical property of the alveolar macrophages (AMs) obtained from induced sputum and analysed cell surface deposition of heavy metals using energy dispersion X-ray analysis (EDX). Sputum cellular DNA damage was assessed by DNA-laddering assay. RESULTS: There was a higher body burden of manganese and nickel in the metal arc-welders than the referents. Among major spirometric indices, only the forced mid-expiratory flow rates (FEF25-75) were reduced in the welders compared with the referents (63.4 ± 14.7 vs. 89.2 ± 26.7, p < 0.01); this reduction was associated with both heavy metal levels (ß: -41.8, 95% CI: -78.5% to -5.1%) and plasma MDA (-0.37; -0.68 to -0.06). In metal arc-welders, significant physical and morphological changes were observed in AMs through microscopic evaluation while EDX analyses demonstrated higher deposition of heavy metals on the AM cell surface than the referents. We also observed a higher degree of DNA damage in the sputum cells of the exposed workers than the referents. CONCLUSION: Heavy metal exposure-induced adverse respiratory effects among metal arc-welders are mediated through haematological and cytological interactions.


Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Macrófagos Alveolares/efeitos dos fármacos , Metais Pesados/efeitos adversos , Exposição Ocupacional/efeitos adversos , Doenças Respiratórias/induzido quimicamente , Soldagem , Adulto , Poluentes Ocupacionais do Ar/análise , Cádmio/efeitos adversos , Cádmio/análise , Humanos , Leucócitos/citologia , Masculino , Malondialdeído/sangue , Manganês/efeitos adversos , Manganês/análise , Metais Pesados/análise , Pessoa de Meia-Idade , Níquel/efeitos adversos , Níquel/análise , Testes de Função Respiratória
11.
J Org Chem ; 80(15): 7360-74, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26151504

RESUMO

A palladium-catalyzed pyrazole-directed regioselective oxidative C(sp2)-H functionalization of the N-phenyl ring in N-phenylpyrazoles to afford either a biaryl bis-pyrazole (via dehydrogenative homocoupling) or N-(o-hydroxyphenyl)pyrazole (via C-H oxygenation) or their mixture is described. The substitutions on the N-phenyl ring and the pyrazole ring and the dilution of the reaction medium with respect to the TFA/TFAA mixture (substrate concentration) have a remarkable influence on the outcome of the reaction. It was discovered that if the reactions were performed under highly dilute conditions (ca. 10 times) then N-(o-hydroxyphenyl)pyrazoles were the major or the sole products.


Assuntos
Quelantes/química , Paládio/química , Pirazóis/química , Pirazóis/síntese química , Catálise , Hidroxilação , Oxirredução
12.
Toxicol Appl Pharmacol ; 267(1): 57-73, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23276653

RESUMO

Diabetes is a menacing problem, particularly to inhabitants of groundwater arsenic contaminated areas needing new medical approaches. This study examines if PLGA loaded nano-insulin (NIn), administered either intraperitoneally (i.p.) or through oral route, has a greater cost-effective anti-hyperglycemic potential than that of insulin in chronically arsenite-fed hyperglycemic mice. The particle size, morphology and zeta potential of nano-insulin were determined using dynamic light scattering method, scanning electronic and atomic force microscopies. The ability of the nano-insulin (NIn) to cross the blood-brain barrier (BBB) was also checked. Circular dichroic spectroscopic (CD) data of insulin and nano-insulin in presence or absence of arsenic were compared. Several diabetic markers in different groups of experimental and control mice were assessed. The mitochondrial functioning through indices like cytochrome c, pyruvate-kinase, glucokinase, ATP/ADP ratio, mitochondrial membrane potential, cell membrane potential and calcium-ion level was also evaluated. Expressions of the relevant marker proteins and mRNAs like insulin, GLUT2, GLUT4, IRS1, IRS2, UCP2, PI3, PPARγ, CYP1A1, Bcl2, caspase3 and p38 for tracking-down the signaling cascade were also analyzed. Results revealed that i.p.-injected nano-encapsulated-insulin showed better results; NIn, due to its smaller size, faster mobility, site-specific release, could cross BBB and showed positive modulation in mitochondrial signaling cascades and other downstream signaling molecules in reducing arsenic-induced-hyperglycemia. CD data indicated that nano-insulin had less distorted secondary structure as compared with that of insulin in presence of arsenic. Thus, overall analyses revealed that PLGA nano-insulin showed better efficacy in combating arsenite-induced-hyperglycemia than that of insulin and therefore, has greater potentials for use in nano-encapsulated form.


Assuntos
Arsênio/toxicidade , Hiperglicemia/induzido quimicamente , Hiperglicemia/prevenção & controle , Insulina/administração & dosagem , Ácido Láctico/administração & dosagem , Nanopartículas/administração & dosagem , Ácido Poliglicólico/administração & dosagem , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Feminino , Hiperglicemia/metabolismo , Insulina/química , Insulina/metabolismo , Ácido Láctico/química , Ácido Láctico/metabolismo , Masculino , Camundongos , Nanopartículas/química , Ácido Poliglicólico/química , Ácido Poliglicólico/metabolismo , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Distribuição Aleatória
13.
Zhong Xi Yi Jie He Xue Bao ; 10(6): 681-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22704418

RESUMO

OBJECTIVE: In the present study, the anticancer potential of platinum nanoparticles Bioplatin is explored and the mode of interactions of Bioplatin with calf thymus DNA and honey was analyzed. METHODS: Bioplatin was synthesized with the help of green nanotechnology and characterized by particle size, zeta potential and surface morphology. The interaction of Bioplatin with DNA and honey was also checked with the help of circular dichroism spectroscopy and Fourier-transform infrared spectroscopy, respectively. The anticancer potential of Bioplatin was evaluated on peripheral blood mononuclear cells and A375 cells in vitro by analyzing results of MTT (3-(4,5)-dimethyl-thiahiazo-(-z-y1)-3,5-di-phenytetrazoliumromide), fluorescence microscopic studies and DNA fragmentation assay. RESULTS: Bioplatin exhibited a small particle size of 137.5 nm and a surface charge of -35.8 mV. Bioplatin interacted with DNA and brought in effective changes in structure and conformation of DNA, and formed a new complex that increased its stability of DNA intercalated with the base pair of DNA. In vitro studies demonstrated that Bioplatin arrested cell proliferation, and induced chromatin condensation and internucleosomal DNA fragmentation. CONCLUSION: Bioplatin induces apoptosis in cancer cells and may have some beneficial effect against human carcinoma. It interacts with DNA, brings stabilization to DNA, and thus prevents the replication of DNA.


Assuntos
Antineoplásicos , Química Verde , Nanopartículas , Platina , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Bovinos , Linhagem Celular Tumoral , Dicroísmo Circular , DNA , Fragmentação do DNA , Humanos , Nanotecnologia , Tamanho da Partícula , Platina/administração & dosagem , Platina/farmacologia
14.
Zhong Xi Yi Jie He Xue Bao ; 10(5): 546-54, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22587977

RESUMO

OBJECTIVE: To examine if a homeopathic mother tincture (Phytolacca Decandra) is capable of precipitating silver nanoparticles from silver nitrate (AgNO(3)) and to characterize the biosynthesized nanoparticles for evaluating their biological activities. METHODS: A total of 100 mg of AgNO(3) was added to 20mL of Milli-Q water and stirred vigorously. Then 5mL of the homeopathic mother tincture of Phytolacca Decandra (ethanolic root extract of Phytolacca decandra) was added and stirred continuously. Reduction took place rapidly at 300K and completed in 10 min as shown by stable light greenish-yellow color of the solution which gave colloid of silver nanoparticles. The colloid solution was then centrifuged at 5000×g to separate the nanoparticles for further use. The nanoparticles were characterized by spectroscopic analysis, particle size analysis and zeta potential measurements, and morphology was analyzed by atomic force microscopy. The drug-DNA interaction was determined by circular dichroism spectrophotometry and melting temperature profiles by using calf thymus DNA as the target. The biological activities were determined using a cancer cell line A549 in vitro and using bacteria Escherichia coli and fungus Saccharomyces cerevisiae as test models. RESULTS: Phytolacca Decandra precipitated silver nanoparticles in ambient conditions. The nanoparticles had 91 nm particle size, with polydispersity index of 0.119 and zeta potential of -15.6 mV. The silver nanoparticles showed anticancer and antibacterial properties, but no clear antifungal properties. CONCLUSION: This could be a novel environment-friendly method to biosynthesize silver nanoparticles using a cost-effective, nontoxic manner. The homeopathic mother tincture may utilize this property of nano-precipitation in curing diseases or disease symptoms.


Assuntos
Química Verde , Homeopatia , Nanopartículas Metálicas , Phytolacca/química , Nitrato de Prata/química , Materia Medica/química , Tamanho da Partícula , Extratos Vegetais/química , Prata/química
15.
Toxicol Appl Pharmacol ; 253(3): 270-81, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21549736

RESUMO

Several naturally occurring coumarin compounds, including scopoletin (7 hydroxy-6 methoxycoumarin), of plant origin have been reported to have anti-cancer potentials. A related but chemically synthesized coumarin, 4-methyl-7-hydroxy coumarin (SC), was also shown to have similar anti-cancer potentials. In the present study, to test if nano-encapsulated SC could be a more potent anti-cancer agent, we encapsulated SC with poly lactide-co-glycolide acid (PLGA) nanoparticles (Nano Coumarin; NC) and tested its potentials with a variety of protocols. NC demonstrated greater efficiency of drug uptake and showed anti-cancer potentials in melanoma cell line A375, as revealed from scanning electronic and atomic force microscopies. To test its possible interaction with target DNA, the combined data of circular dichroism spectra (CD) and melting temperature profile (T(m)) of calf thymus DNA treated with NC were analyzed. Results indicated a concentration dependent interaction of NC with calf thymus DNA, bringing in effective change in structure and conformation, and forming a new complex that increased its stability. Particle size and morphology of NC determined through polydispersity index and zeta potential using dynamic light scattering qualified NC to be a more potent anti-cancer agent than SC. Further, SC and NC showed negligible cytotoxic effects on normal skin cells and peripheral blood mononuclear cells of mice. Distribution assay of PLGA nanoparticles in different tissues like brain, heart, kidneys, liver, lungs, and spleen in mice revealed the presence of nanoparticles in different tissues including brain, indicating that the particles could cross the blood brain barrier, significant information for drug design.


Assuntos
Antineoplásicos/administração & dosagem , Cumarínicos/administração & dosagem , DNA/química , Ácido Láctico/administração & dosagem , Nanocápsulas/administração & dosagem , Ácido Poliglicólico/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Bovinos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Cumarínicos/farmacocinética , Cumarínicos/farmacologia , Humanos , Marcação In Situ das Extremidades Cortadas , Ácido Láctico/farmacocinética , Camundongos , Ácido Poliglicólico/farmacocinética , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Distribuição Tecidual
16.
Artigo em Inglês | MEDLINE | ID: mdl-20953431

RESUMO

Ethanolic extract of Polygala senega (EEPS) had little or no cytotoxic effects on normal lung cells, but caused cell death and apoptosis to lung cancer cell line A549. In the present paper, ethanolic root extract of P. senega (EEPS) was nanoencapsulated (size: 147.7 nm) by deploying a biodegradable poly-(lactic-co-glycolic) acid (PLGA). The small size of the NEEPS resulted in an enhanced cellular entry and greater bioavailability. The growth of cancer cells was inhibited better by NEEPS than EEPS. Both EEPS and NEEPS induced apoptosis of A549 cells, which was associated with decreased expression of survivin, PCNA mRNA, and increased expression of caspase-3, p53 mRNAs of A549 cells. The results show that the anticancer potential of the formulation of EEPS-loaded PLGA nanoparticles was more effective than EEPS per se, probably due to more aqueous dispersion after nanoencapsulation. Therefore, nanoencapsulated ethanolic root extract of P. senega may serve as a potential chemopreventive agent against lung cancer.

17.
Artigo em Inglês | MEDLINE | ID: mdl-19617203

RESUMO

In homeopathy, ability of ultra-high diluted drugs at or above potency 12C (diluted beyond Avogadro's limit) in ameliorating/curing various diseases is often questioned, particularly because the mechanism of action is not precisely known. We tested the hypothesis if suitable modulations of signal proteins could be one of the possible pathways of action of a highly diluted homeopathic drug, Secale cornutum 30C (diluted 10(60) times; Sec cor 30). It could successfully combat DMBA + croton oil-induced skin papilloma in mice as evidenced by histological, cytogenetical, immunofluorescence, ELISA and immunoblot findings. Critical analysis of several signal proteins like AhR, PCNA, Akt, Bcl-2, Bcl-xL, NF-κB and IL-6 and of pro-apoptotic proteins like cytochrome c, Bax, Bad, Apaf, caspase-3 and -9 revealed that Sec cor 30 suitably modulated their expression levels along with amelioration of skin papilloma. FACS data also suggested an increase of cell population at S and G2 phases and decrease in sub-G1 and G1 phages in carcinogen-treated drug-unfed mice, but these were found to be near normal in the Sec cor 30-fed mice. There was reduction in genotoxic and DNA damages in bone marrow cells of Sec Cor 30-fed mice, as revealed from cytogenetic and Comet assays. Changes in histological features of skin papilloma were noted. Immunofluorescence studies of AhR and PCNA also suggested reduced expression of these proteins in Sec cor 30-fed mice, thereby showing its anti-cancer potentials against skin papilloma. Furthermore, this study also supports the hypothesis that potentized homeopathic drugs act at gene regulatory level.

18.
Artigo em Inglês | MEDLINE | ID: mdl-19244296

RESUMO

The present study was undertaken to examine if microdoses of ultra-high diluted arsenic trioxide (a potentized homeopathic remedy, Arsenicum Album 200C, diluted 10(-400) times) have hepatoprotective potentials in mice subjected to repeated injections of arsenic trioxide. Arsenic intoxicated mice were divided into: (i) those receiving Arsenicum Album-200C daily, (ii) those receiving the same dose of diluted succussed alcohol (Alc 200C) and (iii) another group receiving neither drug nor succussed alcohol. Two other control groups were also maintained: one fed normal diet only and the other receiving normal diet and Alc-200C. Toxicity biomarkers like aspartate and alanine aminotransferases, glutathione reductase, catalase, succinate dehydrogenase, superoxide dismutase and reduced glutathione contents were periodically assayed keeping the observer "blinded". Additionally, electron microscopic studies and gelatin zymography for matrix metalloproteinases of liver tissues were made at day 90 and 120. Blood glucose, hemoglobin, estradiol and testosterone contents were also studied. Compared to controls, Arsenicum Album-200C fed mice showed positive modulations of all parameters studied, thereby providing evidence of protective potentials of the homeopathic drug against chronic arsenic poisoning.

19.
Artigo em Inglês | MEDLINE | ID: mdl-21647317

RESUMO

CRUDE ETHANOLIC EXTRACT OF THUJA OCCIDENTALIS (FAM: Cupressaceae) is used as homeopathic mother tincture (TOΦ) to treat various ailments, particularly moles and tumors, and also used in various other systems of traditional medicine. Anti-proliferative and apoptosis-inducing properties of TOΦ and the thujone-rich fraction (TRF) separated from it have been evaluated for their possible anti-cancer potentials in the malignant melanoma cell line A375. On initial trial by S-diphenyltetrazolium bromide assay, both TOΦ and TRF showed maximum cytotoxic effect on A375 cell line while the other three principal fractions separated by chromatography had negligible or no such effect, because of which only TRF was further characterized and subjected to certain other assays for determining its precise anti-proliferative and apoptotic potentials. TRF was reported to have a molecular formula of C(10)H(16)O with a molecular weight of 152. Exposure of TRF of Thuja occidentalis to A375 cells in vitro showed more cytotoxic, anti-proliferative and apoptotic effects as compared with TOΦ, but had minimal growth inhibitory responses when exposed to normal cells (peripheral blood mononuclear cell). Furthermore, both TOΦ and TRF also caused a significant decrease in cell viability, induced inter-nucleosomal DNA fragmentation, mitochondrial transmembrane potential collapse, increase in ROS generation, and release of cytochrome c and caspase-3 activation, all of which are closely related to the induction of apoptosis in A375 cells. Thus, TRF showed and matched all the anti-cancer responses of TOΦ and could be the main bio-active fraction. The use of TOΦ in traditional medicines against tumors has, therefore, a scientific basis.

20.
Zhong Xi Yi Jie He Xue Bao ; 9(3): 320-7, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21419086

RESUMO

OBJECTIVE: To evaluate anticancer potentials of Polygala senega on lung cancer induced by benzo[a]pyrene (B[a]P) in mice. METHODS: Swiss albino mice were divided into five groups with each containing six animals. Group 1 served as control, and the animals received olive oil as vehicle. Group 2 animals were treated with B[a]P (50 mg/kg body weight dissolved in olive oil) orally twice a week for four consecutive weeks. Group 3 animals were fed B[a]P as in group 2 and 48% alcohol (since the vehicle of the remedy was alcohol). Group 4 animals were B[a]P-intoxicated mice (as in group 2) which were additionally fed ethanolic extract of Polygala senega (EEPS) daily for 16 weeks. EEPS treatment started after the first dose of B[a]P. Group 5 animals were treated with EEPS alone for 16 weeks to test cytotoxicity of EEPS if any. Mice were sacrificed after 16 weeks and the following parameters were assessed: the anti-oxidant activity measured by 2,2-diphenyl-1-picrylhydrazyl free radical assay, tumor incidence, lung weight and body weight, DNA damage evaluation by comet assay and enzyme-linked immunosorbent assay (ELISA); toxicity biomarkers like catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, lipid peroxidation (LPO) and total thiol content were also detected. RESULTS: Treatment with EEPS increased the final body weight and significantly decreased the lung weight in group 4 mice (P<0.01) compared with group 3 mice. Comet assay showed that EEPS-treated mice in group 4 presented a decrease of DNA damage significantly (P<0.01) in lung tissues. There was a significant increase observed in the level of p53 in group 4 as compared with group 3 (P<0.01) detected by ELISA. A highly significant increase in tissue LPO with concomitant decrease in the activity of anti-oxidants was observed in group 2 and group 3 mice (P<0.05) compared with the control mice. These adverse changes were reversed significantly in group 4 mice (P<0.01). CONCLUSION: Chemopreventive potentials of Polygala senega against chemically induced lung cancer in mice are confirmed.


Assuntos
Adenocarcinoma/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Fitoterapia , Polygala/química , Adenocarcinoma/induzido quimicamente , Adenocarcinoma de Pulmão , Animais , Benzo(a)pireno/efeitos adversos , Neoplasias Pulmonares/induzido quimicamente , Camundongos , Extratos Vegetais/uso terapêutico , Raízes de Plantas/química
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