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1.
Amino Acids ; 56(1): 20, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38460024

RESUMO

The mutant matrilineal (mtl) gene encoding patatin-like phospholipase activity is involved in in-vivo maternal haploid induction in maize. Doubling of chromosomes in haploids by colchicine treatment leads to complete fixation of inbreds in just one generation compared to 6-7 generations of selfing. Thus, knowledge of patatin-like proteins in other crops assumes great significance for in-vivo haploid induction. So far, no online tool is available that can classify unknown proteins into patatin-like proteins. Here, we aimed to optimize a machine learning-based algorithm to predict the patatin-like phospholipase activity of unknown proteins. Four different kernels [radial basis function (RBF), sigmoid, polynomial, and linear] were used for building support vector machine (SVM) classifiers using six different sequence-based compositional features (AAC, DPC, GDPC, CTDC, CTDT, and GAAC). A total of 1170 protein sequences including both patatin-like (585 sequences) from various monocots, dicots, and microbes; and non-patatin-like proteins (585 sequences) from different subspecies of Zea mays were analyzed. RBF and polynomial kernels were quite promising in the prediction of patatin-like proteins. Among six sequence-based compositional features, di-peptide composition attained > 90% prediction accuracies using RBF and polynomial kernels. Using mutual information, most explaining dipeptides that contributed the highest to the prediction process were identified. The knowledge generated in this study can be utilized in other crops prior to the initiation of any experiment. The developed SVM model opened a new paradigm for scientists working in in-vivo haploid induction in commercial crops. This is the first report of machine learning of the identification of proteins with patatin-like activity.


Assuntos
Máquina de Vetores de Suporte , Zea mays , Zea mays/genética , Haploidia , Peptídeos/genética , Fosfolipases/genética
2.
Tissue Eng Regen Med ; 19(5): 1013-1031, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35511336

RESUMO

BACKGROUND: The mesenchymal stem cells (MSCs) have enormous therapeutic potential owing to their multi-lineage differentiation and self-renewal properties. MSCs express growth factors, cytokines, chemokines, and non-coding regulatory RNAs with immunosuppressive, anti-tumor, and migratory properties. MSCs also release several anti-cancer molecules via extracellular vesicles, that act as pro-apoptotic/tumor suppressor factors. This study aimed to identify the stem cell-derived secretome that could exhibit anti-cancer properties through molecular profiling of cargos in MSC-derived exosomes. METHODS: Human umbilical cord mesenchymal stem cells (hUCMSCs) were isolated from umbilical cord tissues and culture expanded. Subsequently, exosomes were isolated from hUCMSC conditioned medium and characterized by DLS, electron microscopy. Western blot for exosome surface marker protein CD63 expression was performed. The miRNA profiling of hUCMSCs and hUCMSC-derived exosomes was performed, followed by functional enrichment analysis. RESULTS: The tri-lineage differentiation potential, fibroblastic morphology, and strong expression of pluripotency genes indicated that isolated fibroblasts are MSCs. The isolated extracellular vesicles were 133.8 ± 42.49 nm in diameter, monodispersed, and strongly expressed the exosome surface marker protein CD63. The miRNA expression profile and gene ontology (GO) depicted the differential expression patterns of high and less-expressed miRNAs that are crucial to be involved in the regulation of apoptosis. The LCMS/MS data and GO analysis indicate that hUCMSC secretomes are involved in several oncogenic and inflammatory signaling cascades. CONCLUSION: Primary human MSCs released miRNAs and growth factors via exosomes that are increasingly implicated in intercellular communications, and hUCMSC-exosomal miRNAs have a critical influence in regulating cell death and apoptosis of cancer cells.


Assuntos
Exossomos , Células-Tronco Mesenquimais , MicroRNAs , Neoplasias , Meios de Cultivo Condicionados/farmacologia , Citocinas/metabolismo , Exossomos/metabolismo , Humanos , Células-Tronco Mesenquimais/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias/metabolismo , Proteômica , Cordão Umbilical
3.
Acta Pharmacol Sin ; 43(11): 2759-2776, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35379933

RESUMO

Three major approaches of cancer therapy can be enunciated as delivery of biotherapeutics, tumor image analysis, and immunotherapy. Liposomes, artificial fat bubbles, are long known for their capacity to encapsulate a diverse range of bioactive molecules and release the payload in a sustained, stimuli-responsive manner. They have already been widely explored as a delivery vehicle for therapeutic drugs as well as imaging agents. They are also extensively being used in cancer immunotherapy. On the other hand, exosomes are naturally occurring nanosized extracellular vesicles that serve an important role in cell-cell communication. Importantly, the exosomes also have proven their capability to carry an array of active pharmaceuticals and diagnostic molecules to the tumor cells. Exosomes, being enriched with tumor antigens, have numerous immunomodulatory effects. Much to our intrigue, in recent times, efforts have been directed toward developing smart, bioengineered, exosome-liposome hybrid nanovesicles, which are augmented by the benefits of both vesicular systems. This review attempts to summarize the contemporary developments in the use of exosome and liposome toward cancer diagnosis, therapy, as a vehicle for drug delivery, diagnostic carrier for tumor imaging, and cancer immunotherapy. We shall also briefly reflect upon the recent advancements of the exosome-liposome hybrids in cancer therapy. Finally, we put forward future directions for the use of exosome/liposome and/or hybrid nanocarriers for accurate diagnosis and personalized therapies for cancers.


Assuntos
Exossomos , Vesículas Extracelulares , Neoplasias , Humanos , Lipossomos , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos
4.
Toxicology ; 378: 10-16, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28069514

RESUMO

More than 26 million people in West Bengal, India, are exposed to arsenic through drinking water, leading to several deleterious endpoints including precancerous and cancerous skin lesions and other non-dermatological health effects. Here, our aim was to identify whether miR21 is associated with such dermatological and non-dermatological health outcomes in chronically exposed humans. A total of 123 subjects from West Bengal were recruited for this study (45 exposed individuals with skin lesions, 38 exposed individuals without skin lesions and 40 unexposed individuals). The miR21 expression patterns in the lymphocytes were studied by quantitative realtime PCR and the effects on downstream targets were validated by Western blotting. Associations between the miR21 expression patterns and non-dermatological health effects were determined from epidemiological survey data. In vitro studies were done with low dose (0.05ppm) of chronic arsenic exposure to HaCaT cells for 15 passages. Interestingly, within the exposed group, the skin lesion individuals showed almost 4.5 fold up-regulation of miR21 compared to the no skin lesion group. The expression of the downstream targets of miR21 (PTEN and PDCD4) varied inversely, while the expression of pAKT and PI3K varied proportionately with its expression levels. Results of in vitro studies showed similar trends. Again miR21 was 2.03 fold up-regulated in the exposed individuals with respiratory diseases compared to the individuals without the same. This study for the first time shows that miR21 plays an important role in contributing to arsenic induced dermatological and non-dermatological health outcomes in an exposed population.


Assuntos
Arsênio/toxicidade , MicroRNAs , Transtornos Respiratórios , Dermatopatias , Poluentes Químicos da Água/toxicidade , Adulto , Arsênio/análise , Arsênio/urina , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Células Cultivadas , Água Potável/análise , Exposição Ambiental , Feminino , Predisposição Genética para Doença , Humanos , Índia/epidemiologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Transtornos Respiratórios/induzido quimicamente , Transtornos Respiratórios/epidemiologia , Transtornos Respiratórios/genética , Transtornos Respiratórios/urina , Dermatopatias/induzido quimicamente , Dermatopatias/epidemiologia , Dermatopatias/genética , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/urina
5.
Biochim Biophys Acta ; 1852(9): 1989-99, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26148937

RESUMO

Cholangiocarcinoma (CCA), a common primary malignant tumor of bile duct epithelia, is highly prevalent in Asian countries and unresponsive to chemotherapeutic drugs. Thus, a newly recognized biological entity for early diagnosis and treatment is highly needed. Exosomes are small membrane bound vesicles found in body fluids and released by most cell types including cancer cells. The vesicles contain specific subset of proteins and nucleic acids corresponding to cell types and play essential roles in pathophysiological processes. The present study aimed to assess the protein profiles of CCA-derived exosomes and their potential roles. We have isolated exosomes from CCA cells namely KKU-M213 and KKU-100 derived from Thai patients and their roles were investigated by incubation with normal human cholangiocyte (H69) cells. Exosomes were internalized into H69 cells and had no effects on viability or proliferation of the host cells. Interestingly, the exosomes from KKU-M213 cells only induced migration and invasion of H69 cells. Proteomic analysis of the exosomes from KKU-M213 cells disclosed multiple cancer related proteins that are not present in H69 exosomes. Consistent with the protein profile, treatment with KKU-M213 exosomes induced ß-catenin and reduced E-cadherin expressions in H69 cells. Collectively, our results suggest that a direct cell-to-cell transfer of oncogenic proteins via exosomal pathway may be a novel mechanism for CCA progression and metastasis.

6.
Eur J Pharmacol ; 723: 148-55, 2014 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-24360936

RESUMO

Cholangiocarcinoma (CCA), the common primary malignant tumor of bile duct epithelial cells, is unresponsive to most chemotherapeutic drugs. Diagnosis with CCA has a poor prognosis, and therefore urgently requires effective therapeutic agents. In the present study we investigated anti-cancer effects of andrographolide analogue 3A.1 (19-tert-butyldiphenylsilyl-8, 17-epoxy andrographolide) and its mechanism in human CCA cell line KKU-M213 derived from a Thai CCA patient. By 24h after exposure, the analogue 3A.1 exhibited a potent cytotoxic effect on KKU-M213 cells with an inhibition concentration 50 (IC50) of approximately 8.0µM. Analogue 3A.1 suppressed DNA topoisomerase II α (Topo II α) protein expression, arrested the cell cycle at sub G0/G1 phase, induced cleavage of DNA repair protein poly (ADP-ribose) polymerases-1 (PARP-1), and enhanced expression of tumor suppressor protein p53 and pro-apoptotic protein Bax. In addition, analogue 3A.1 induced caspase 3 activity and inhibited cyclin D1, CDK6, and COX-2 protein expression. These results suggest that andrographolide analogue 3A.1, a novel topo II inhibitor, has significant potential to be developed as a new anticancer agent for the treatment of CCA.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Ligação a DNA/antagonistas & inibidores , Diterpenos/farmacologia , Compostos de Organossilício/farmacologia , Antígenos de Neoplasias , Apoptose , Neoplasias dos Ductos Biliares/metabolismo , Caspase 3/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Colangiocarcinoma/metabolismo , Ciclo-Oxigenase 2/metabolismo , DNA/metabolismo , DNA Topoisomerases Tipo II , Humanos , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína X Associada a bcl-2/metabolismo
7.
Invest New Drugs ; 31(2): 320-32, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22899371

RESUMO

Topoisomerase II α enzyme plays a critical role in DNA replication process. It controls the topologic states of DNA during transcription and is essential for cell proliferation. Human DNA topoisomerase II α (hTopo II α) is a promising chemotherapeutic target for anticancer agents against a variety of cancer types. In the present study, andrographolide and its structurally modified analogues were investigated for their inhibitory activities on hTopo II α enzyme. Five out of nine andrographolide analogues potently reduced hTopo II α activity and inhibited cell proliferation in four mammalian cell lines (Hela, CHO, BCA-1 and HepG2 cells). IC50 values for cytotoxicity of analogues 3A.1, 3A.2, 3A.3, 1B and 2C were 4 to 7 µM. Structure-activity relationship studies revealed that both core structure of andrographolide and silicon based molecule of functional group were important for the inhibition of hTopo II α activity whereas position C-19 of analogues was required for anti-proliferation. In addition, the analogue 2C at 10 µM concentration inhibited hTopo II α, and induced apoptosis with nuclear fragmentation and formation of apoptotic bodies in HepG2 cells. The analogue 2C may, therefore, have a therapeutic potential as effective anticancer agent targeting the hTopo II α functions.


Assuntos
Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias da Mama/patologia , Proteínas de Ligação a DNA/antagonistas & inibidores , Diterpenos/farmacologia , Inibidores da Topoisomerase II/farmacologia , Andrographis/química , Animais , Antígenos de Neoplasias , Neoplasias da Mama/tratamento farmacológico , Células CHO , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cricetinae , Replicação do DNA/efeitos dos fármacos , DNA Topoisomerases Tipo II , Diterpenos/síntese química , Diterpenos/química , Feminino , Células HeLa , Células Hep G2 , Humanos , Relação Estrutura-Atividade , Inibidores da Topoisomerase II/síntese química
8.
Zhong Xi Yi Jie He Xue Bao ; 10(2): 210-27, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22313889

RESUMO

OBJECTIVE: To examine if potentiated homeopathic drug Arsenicum Album 30C (Ars Alb 30C) can reduce sodium arsenite-induced toxicity in Escherichia coli. METHODS: E. coli were exposed to low arsenite insult after they grew up to log phase in standard Luria-Bertani medium. E. coli were treated with 1 or 2 mmol/L sodium arsenite alone (control), or Ars Alb 30C was added to the medium of a subset of sodium arsenite-treated bacteria (drug-treated), or homeopathically agitated alcohol was added to the medium containing a subset of sodium arsenite-treated bacteria (placebo-treated). A sub-set of untreated E. coli served as the negative control. Glucose uptake, specific activities of hexokinase, lipid peroxidase (LPO), superoxide dismutase (SOD) and catalase, intra- and extra-cellular sodium arsenite content, cell growth, cell membrane potential, DNA damage, intracellular reactive oxygen species (ROS), adenosine triphosphate (ATP) and free glutathione content and expressions of arsB and ptsG gene in normal control, sodium arsenite-treated, drug-treated and placebo-treated E. coli were analyzed. Treatments were blinded and randomized. RESULTS: In sodium arsenite-treated E. coli, glucose uptake, intracellular ROS, LPO and DNA damage increased along with decrease in the specific activities of hexokinase, SOD and catalase, intracellular ATP and free glutathione contents and cell membrane potential and growth, and there were increases in expression levels of arsB gene and ptsG gene. Ars Alb 30C administration reduced arsenic toxicity in E. coli by inhibiting generation of ROS and increasing tolerance to arsenite toxicity and cell growth. CONCLUSION: Ars Alb 30C ameliorated arsenic toxicity and DNA damage, validating efficacy of ultra-highly diluted remedies used in homeopathy.


Assuntos
Arsenicais/antagonistas & inibidores , Arsenitos/toxicidade , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Homeopatia , Espécies Reativas de Oxigênio/metabolismo , Dano ao DNA , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Peroxidação de Lipídeos , Regulação para Cima
9.
Exp Biol Med (Maywood) ; 237(1): 64-76, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22169161

RESUMO

Helonias dioica (HD) is a threatened species of herb growing in North America. It is used as a traditional medicine for treating various ailments particularly related to reproductive issues. The root is reported to contain approximately 10% of a saponin (chamaelirin; C(36)H(62)O(18)) apart from certain other fatty acids. As saponins are known to have hypoglycemic effects, we suspected its possible antihyperglycemic potentials. We injected intraperitoneally alloxan (ALX) at the dose of 200 mg/kg body weight (bw) to induce hyperglycemia in mice and tested possible hypoglycemic effects of HD in vivo by deploying two doses (100 and 200 mg/kg bw, respectively). We also tested its effects on the isolated pancreatic islets cells in vitro. We used various standard protocols like reactive oxygen species (ROS) generation and DNA damage, activities of biomarkers like catalase (CAT), superoxide dismutase (SOD), lipid peroxidase (LPO), reduced glutathione (GSH) of the pancreas tissue and glucokinase and glycogen content of the liver of hyperglycemic mice. With a mechanistic approach, we also tracked down the possible signaling pathway involved. We found an elevated level of ROS generation, LPO and overexpression of inducible nitric oxide synthase (iNOS), tumor necrosis factor α (TNF-α), p38 Map kinase (p38 MAPK), nuclear factor (NF)-κß, interferon gamma (IFN-γ), cytochrome c, caspase 3, poly [ADP ribose] polymerase (PARP) and cyclo oxygenase 2 (COX2) in ALX-induced diabetic mouse. Treatment of hyperglycemic mice with both the doses of HD showed a significant decrease with respect to all these parameters of study. Thus, our results suggest that HD prevents ALX-induced islet cell damage and possesses antihyperglycemic and antioxidative potentials.


Assuntos
Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/farmacologia , Magnoliopsida , Estresse Oxidativo/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/farmacologia , Plantas Medicinais/metabolismo , Aloxano , Animais , Caspase 3/biossíntese , Catalase/metabolismo , Células Cultivadas , Ciclo-Oxigenase 2/biossíntese , Citocromos c/biossíntese , Dano ao DNA , Espécies em Perigo de Extinção , Glucoquinase/metabolismo , Glutationa/metabolismo , Hiperglicemia/induzido quimicamente , Hipoglicemiantes/administração & dosagem , Ilhotas Pancreáticas/efeitos dos fármacos , Peróxidos Lipídicos/metabolismo , Glicogênio Hepático/análise , Magnoliopsida/química , Camundongos , NF-kappa B/biossíntese , Óxido Nítrico Sintase Tipo II/biossíntese , Pâncreas/metabolismo , Extratos Vegetais/administração & dosagem , Raízes de Plantas/química , Poli(ADP-Ribose) Polimerases/biossíntese , Espécies Reativas de Oxigênio/metabolismo , Saponinas/análise , Saponinas/farmacologia , Transdução de Sinais , Superóxido Dismutase/metabolismo , Fator de Necrose Tumoral alfa/biossíntese , Proteínas Quinases p38 Ativadas por Mitógeno/biossíntese
10.
BMB Rep ; 44(10): 647-52, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22026997

RESUMO

The protein transduction domains have been reported to have potential to deliver the exogenous molecules, including proteins, to living cells. However, poor transduction of proteins limits therapeutic application. In this study, we examined whether imipramine could stimulate the transduction efficiency of PEP-1 fused proteins into astrocytes. PEP-1-catalase (PEP-1- CAT) was transduced into astrocytes in a time- and dose-dependent manner, reducing cellular toxicity induced by H(2)O(2). Additionally, the group of PEP-1-CAT (+) imipramine showed enhancement of transduction efficiency and therefore increased cellular viability than that of PEP-1-CAT alone. In the gerbil ischemia models, PEP-1-CAT displayed significant neuroprotection in the CA1 region of the hippocampus. Interestingly, PEP-1-CAT (+) imipramine prevented neuronal cell death and lipid peroxidation more markedly than PEP-1-CAT alone. Therefore, our results suggest that imipramine can be used as a drug to enhance the transduction of PEP-1 fusion proteins to cells or animals and their efficacies against various disorders.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/patologia , Catalase/uso terapêutico , Cisteamina/análogos & derivados , Imipramina/uso terapêutico , Neurônios/patologia , Fármacos Neuroprotetores/uso terapêutico , Peptídeos/uso terapêutico , Animais , Antidepressivos Tricíclicos/farmacologia , Antidepressivos Tricíclicos/uso terapêutico , Astrócitos/efeitos dos fármacos , Astrócitos/fisiologia , Catalase/genética , Catalase/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cisteamina/farmacologia , Cisteamina/uso terapêutico , Gerbillinae , Imipramina/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Peptídeos/genética , Peptídeos/farmacologia , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Recombinantes de Fusão/uso terapêutico , Transdução Genética
11.
Zhong Xi Yi Jie He Xue Bao ; 9(8): 901-12, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21849152

RESUMO

OBJECTIVE: Whether ultra-highly diluted homeopathic remedies can affect living systems is questionable. Therefore, this study sees value in the analysis of whether homeopathically diluted glucose 30C has any effect on Escherichia coli exposed to arsenite stress. METHODS: E. coli were cultured to their log phase in standard Luria-Bertani medium and then treated with either 1 mmol/L or 2 mmol/L sodium arsenite, with or without supplementation of either 1% or 3% glucose, an ultra-highly diluted and agitated ethanolic solution (70%) of glucose (diluted 10(60) times), glucose 30C or 70% ethanol (placebo) in the medium. Glucose uptake, specific activities of hexokinase and glucokinase, membrane potential, intracellular adenosine triphosphate (ATP) and expression of glucose permease in E. coli were analyzed at two different time intervals. Arsenic content in E. coli (intracellular) and in the spent medium (extracellular) was also determined. RESULTS: In arsenite-exposed E. coli, the glucose uptake increased along with decreases in the specific activities of hexokinase and glucokinase, intracellular ATP and membrane potential and an increase in the gene expression level of glucose permease. Glucose uptake increased further by addition of 1%, 3% or ultra-highly diluted glucose in the medium, but not by the placebo. CONCLUSION: The results demonstrated the efficacy of the ultra-highly diluted and agitated glucose in mimicking the action of actual glucose supplementation and its ability to modulate expressions of hexokinase and glucokinase enzymes and glucose permease genes, thereby validating the efficacy of ultra-high dilutions used in homeopathy.


Assuntos
Arsenitos/química , Transporte Biológico/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Glucose/metabolismo , Glucose/farmacologia , Contagem de Colônia Microbiana , Glucose/administração & dosagem , Materia Medica/química
12.
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.

13.
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.

14.
Zhong Xi Yi Jie He Xue Bao ; 8(7): 645-54, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20619141

RESUMO

OBJECTIVE: Anti-cancer potentials of scopoletin (7-hydroxy-6-methoxy coumarin) separated from plant extract (Gelsemium sempervirens) were demonstrated earlier from our in vitro studies. In the present study, its in vivo effects have been evaluated in mice. METHODS: Mice were chronically administered 7,12-dimethylbenz [a] anthracene (DMBA) once a week and croton oil twice a week on their back, which resulted in the development of fully grown finger-like projections (papilloma) after 24 weeks. Two subgroups of mice (drug-treated) were treated with two doses of scopoletin (50 mg and 100 mg/kg body weight) respectively while control received 2% ethyl alcohol (the "vehicle" of scopoletin). After the 24-week drug administration, expressions of several key receptors such as aryl hydrocarbon receptor (AhR) and signal proteins like p53, cytochrome P450 1A1 (CYP1A1), proliferating cell nuclear antigen (PCNA), signal transducer and activator of transcription-3 (Stat-3), survivin, matrix metalloproteinase-2 (MMP-2), cyclin D1, c-myc, tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) and caspase-3, and some anti-oxidant markers were studied. Lipid peroxidation, superoxide dismutase, catalase, glutathione peroxidase and glutathione-s-transferase in supernatant were also detected. RESULTS: Carcinogens induced toxicity, and over-expression of AhR, CYP1A1, PCNA, Stat-3, survivin, MMP-2, cyclin D1 and c-myc and down-regulation of p53, caspase-3 and TIMP-2. In mice treated with scopoletin, the expressions of these proteins and toxicity biomarkers were reverted. CONCLUSION: Since AhR is known to be ligand-activated by DMBA to release signals for several downstream proteins initiating reactive oxygen species generation, the down-regulation of AhR by scopoletin appeared to play a significant role in subsequent down-regulation of some key signal proteins. One possible mechanism of down-regulation of AhR may be through competitive inhibition by scopoletin. Mitogen-activated protein kinases may also have some critical role. This compound can be considered as a possible candidate for chemoprevention.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Papiloma/metabolismo , Escopoletina/farmacologia , Neoplasias Cutâneas/metabolismo , 9,10-Dimetil-1,2-benzantraceno/efeitos adversos , Animais , Antineoplásicos Fitogênicos/uso terapêutico , Caspase 3/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Papiloma/induzido quimicamente , Papiloma/tratamento farmacológico , Fitoterapia , Escopoletina/uso terapêutico , Transdução de Sinais , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/tratamento farmacológico , Inibidor Tecidual de Metaloproteinase-2/metabolismo
15.
Parasitol Int ; 59(2): 166-72, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20079879

RESUMO

The microaerophilic intestinal parasitic protozoan Entamoeba histolytica has been previously shown to be highly susceptible to oxidative stress induced by hydrogen peroxide. However the mechanism of cell death was not investigated. Studies presented in this paper demonstrate several morphological features in the parasite when exposed to H(2)O(2) which are identical to metazoan apoptotic phenotype indicating a possible apoptosis-like cell death exhibited by E. histolytica in response to H(2)O(2) treatment. Trophozoite cell shrinkage, DNA fragmentation, phosphatidyl serine externalization and increased endogenous reactive oxygen species level have been observed in the protozoan parasite when exposed to 2.0mM H(2)O(2) for different time periods. Although the parasite genome is completely devoid of any of the homologues of mammalian caspases it still codes for a huge number of cysteine proteases which may take over the apoptotic function of the caspases. But the present study indicates the existence of a cysteine protease independent programmed cell death in the parasite since E-64 the specific cysteine protease inhibitor could not rescue the cells from H(2)O(2) induced apoptosis-like cell death.


Assuntos
Apoptose/efeitos dos fármacos , Entamoeba histolytica/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Animais , Apoptose/fisiologia , Cisteína Proteases/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Fragmentação do DNA , Entamoeba histolytica/enzimologia , Entamoeba histolytica/crescimento & desenvolvimento , Entamoeba histolytica/fisiologia , Citometria de Fluxo , Humanos , Leucina/análogos & derivados , Leucina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Trofozoítos/efeitos dos fármacos
16.
Eur J Pharmacol ; 626(2-3): 115-22, 2010 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-19786013

RESUMO

Crude ethanolic extract of the plant Lycopodium clavatum has long been used in complementary and alternative medicine for treating various liver ailments and Alzheimer's disease. It has also been claimed to have potential anti-cancer properties in vivo in mice chronically fed liver carcinogens, p-dimethylamino azobenzene (initiator) and phenobarbital (promoter). Incidentally, crude ethanolic extract of Lycopodium clavatum is a mixture of some 201 alkaloids. In order to ascertain if any major fraction can be attributed to have pronounced anti-cancer effect, we examined this major fraction by eluting the crude extract in petroleum ether:ethyl aetate (17:3 vol/vol;) solvent and tried to understand its underlying mechanism. Studies on morphological changes, cell viability and cytotoxicity by microscopy and FACS, Western blot and immunofluorescence of Bcl-2, Bax, cytochrome c, caspase-3 were conducted. Lycopodine was found to induce chromatin condensation, inter-nucleosomal DNA fragmentation and enhanced cell population in sub-G1 region along with increase in reactive oxygen species generation and mitochondrial membrane potential depolarization, release of cytochrome c and activation of caspase-3 which are the events closely involved in apoptosis. An overall analysis of results showed that Lycopodine considerably inhibited growth of HeLa cells which indicates its potential use in chemotherapy.


Assuntos
Alcaloides/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Lycopodium/química , Extratos Vegetais/química , Quinolizinas/farmacologia , Acetatos/química , Alcaloides/química , Alcaloides/isolamento & purificação , Alcanos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Citometria de Fluxo , Imunofluorescência , Células HeLa , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Peso Molecular , Quinolizinas/química , Quinolizinas/isolamento & purificação , Espécies Reativas de Oxigênio/metabolismo
17.
Biochem Pharmacol ; 2009 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-19712669

RESUMO

The editor has not accepted the submitted manuscript for publication, and the author was so informed. Due to a subsequent administrative error, the Publisher mistakenly included the manuscript in its Articles in Press service. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

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