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1.
J Tradit Complement Med ; 13(6): 611-622, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38020554

RESUMO

Background: Leishmaniasis is endemic in more than 60 countries with a large number of mortality cases. The current chemotherapy approaches employed for managing the leishmaniasis is associated with severe side effects. Therefore there is a need to develop effective, safe, and cost affordable antileishmanial drug candidates. Purpose of the study: This study was designed to evaluate the in vitro antileishmanial activity of a Prosopis juliflora leaves extract (PJLME) towards the Leishmania donovani parasites. Material and methods: PJLME was evaluated for its cytotoxicity against the L. donovani parasites and the mouse macrophage cells. Further, various in vitro experiments like ROS assay, mitochondrial membrane potential assay, annexin v assay, cell cycle assay, and caspase 3/7 assay were performed to understand the mechanism of cell death. Phytochemical profiling of P. juliflorawas performed by utilizing HPTLC and GC-MS analysis. Results: PJLME demonstrated antileishmanial activity at a remarkably lower concentration of IC50 6.5 µg/mL. Of note, interestingly PJLME IC50 concentration has not demonstrated cytotoxicity against the mouse macrophage cell line. Performed experiments confirmed ROS inducing potential of PJLME which adversely affected the mitochondrial membrane potential and caused loss of mitochondrial membrane potential and thereby ATP levels. PJLME also arrested the cell cycle and induced apoptotic-like cell death in PJLME treated L. donovani promastigotes. Conclusion: The results clearly established the significance of Prosopis juliflora as an effective and safe natural resource for managing visceral leishmaniasis. The findings can be used as a baseline reference for developing novel leads/formulations for effective management of visceral leishmaniasis.

3.
Oncotarget ; 9(54): 30304-30323, 2018 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-30100991

RESUMO

Plant originated drugs/formulations are extensively prescribed by the physicians as a complementary therapy for treating various human ailments including cancer. In this study Prosopis juliflora leaves methanol extract was prepared and exposed to human breast cancer cell lines i.e. MDA-MB-231 and MCF-7 and human keratinocytes HaCaT as a representative of normal cells. Initially, a series of in vitro experiments like cell proliferation, migration, colony formation, cell cycle arrest and inhibition of angiogenesis. After confirmation of the efficient and selective activity against triple negative breast cancer cell line, we further evaluated the possible mechanism of inducing cell death and experiments like detection of reactive oxygen species, caspases and poly (ADP-ribose) polymerase cleavage study and Annexin V assay were performed. We also evaluated in vivo anti tumorigenic activity of the P. juliflora leaves by using 4T1 cells (a triple negative mouse origin breast cancer cell line) and BALB/c xenograft mouse model. In vitro experiments revealed that methanol extract of Prosopis juliflora leaves possess impressive anti-breast cancer activity more specifically against triple negative breast cancer cells, while the in vivo studies demonstrated that P. juliflora leaves extract significantly suppressed the 4T1 induced tumor growth. Present investigations clearly focus the significance of P. juliflora as an important resource for finding novel leads against triple negative breast cancer. The results may also act as a ready reference towards developing P. juliflora based formulation as an alternative and complementary medicine for the management of breast cancer.

4.
BMC Cell Biol ; 15: 18, 2014 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-24885493

RESUMO

BACKGROUND: Polycomb Group (PcG) proteins are chromatin modifiers involved in early embryonic development as well as in proliferation of adult stem cells and cancer cells. PcG proteins form large repressive complexes termed Polycomb Repressive Complexes (PRCs) of which PRC1 and PRC2 are well studied. Differentiation of human Embryonic Stem (hES) cells into insulin producing cells has been achieved to limited extent, but several aspects of differentiation remain unexplored. The PcG protein dynamics in human embryonic stem (hES) cells during differentiation into pancreatic lineage has not yet been reported. In the present study, the expression of RING1A, RING1B, BMI1, CBX2, SUZ12, EZH2, EED and JARID2 during differentiation of hES cells towards pancreatic lineage was examined. RESULTS: In-house derived hES cell line KIND1 was used to study expression of PcG protein upon spontaneous and directed differentiation towards pancreatic lineage. qRT-PCR analysis showed expression of gene transcripts for various lineages in spontaneously differentiated KIND1 cells, but no differentiation into pancreatic lineage was observed. Directed differentiation induced KIND1 cells grown under feeder-free conditions to transition from definitive endoderm (Day 4), primitive gut tube stage (Day 8) and pancreatic progenitors (Day 12-Day 16) as evident from expression of SOX17, PDX1 and SOX9 by qRT-PCR and Western blotting. In spontaneously differentiating KIND1 cells, RING1A and SUZ12 were upregulated at day 15, while other PcG transcripts were downregulated. qRT-PCR analysis showed transcripts of RING1B, BMI1, SUZ12, EZH2 and EED were upregulated, while RING1A and CBX2 expression remained low and JARID2 was downregulated during directed differentiation of KIND1 cells. Upregulation of BMI1, EZH2 and SUZ12 during differentiation into pancreatic lineage was also confirmed by Western blotting. Histone modifications such as H3K27 trimethylation and monoubiquitinylation of H2AK119 increased during differentiation into pancreatic lineage as seen by Western blotting. CONCLUSION: Our study shows expression of PcG proteins was distinct during spontaneous and directed differentiation. Differentiation into pancreatic lineage was achieved by directed differentiation approach and was associated with increased expression of PcG proteins RING1B, BMI1, EZH2 and SUZ12 accompanied by increase in monoubiquitinylation of H2AK119 and trimethylation of H3K27.


Assuntos
Células-Tronco Embrionárias/citologia , Regulação da Expressão Gênica no Desenvolvimento , Pâncreas/citologia , Proteínas do Grupo Polycomb/genética , Diferenciação Celular , Linhagem Celular , Linhagem da Célula , Células-Tronco Embrionárias/metabolismo , Humanos
5.
In Vitro Cell Dev Biol Anim ; 49(1): 82-93, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23288411

RESUMO

Human embryonic stem cells (hESCs) have the ability to differentiate into all the three lineages and are an ideal starting material to obtain cells of desired lineage for regenerative medicine. Continued efforts are needed to evolve more robust protocols to obtain cells of desired lineages and in larger numbers. Also, it has now been realized that rather than transplanting fully committed cells differentiated in vitro, it may be ideal to transplant committed progenitors which retain the intrinsic ability to proliferate and also differentiate better into multiple lineages based on the in vivo cues. For cardiac regeneration, the desired progenitor is a multipotent cardiovascular progenitor which has the ability to regenerate cardiomyocytes, endothelial cells, and also smooth muscle cells. The present study was undertaken to carefully compare three widely used protocols to differentiate hESCs into cardiac progenitors, viz., spontaneous differentiation, differentiation by END-2-conditioned medium, and directed differentiation using growth factors followed by quantitative PCR to study the relative expression of early cardiovascular markers. hESC differentiation mimicked the early embryonic development, and the transition into mesoendoderm, mesoderm, early cardiac progenitors, and cardiac cells associated with spontaneous beating was clearly evident in all the three groups. However, compared to spontaneous and END-2-associated differentiation, directed differentiation led to several-fold higher expression of cardiac transcripts (>75-fold Nkx2.5 and >150-fold Tbx5) in response to the stage-specific addition of well-established cardiogenic inducers and inhibitors of specific signaling pathways. We propose to use tripotent cardiovascular progenitors derived by directed differentiation for further preclinical studies.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Embrionárias/fisiologia , Células-Tronco Multipotentes/fisiologia , Miocárdio/citologia , Medicina Regenerativa/métodos , Diferenciação Celular/efeitos dos fármacos , Meios de Cultivo Condicionados/química , Primers do DNA/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/farmacologia , Microscopia de Fluorescência , Reação em Cadeia da Polimerase
6.
Stem Cells Dev ; 21(1): 1-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21780911

RESUMO

Very small embryonic-like stem cells (VSELs) are possibly lost during cord blood banking and bone marrow (BM) processing for autologus stem cell therapy mainly because of their small size. The present study was conducted on human umbilical cord blood (UCB, n=6) and discarded red blood cells (RBC) fraction obtained after separation of mononuclear cells from human BM (n=6), to test this hypothesis. The results show that VSELs, which are pluripotent stem cells with maximum regenerative potential, settle along with the RBCs during Ficoll-Hypaque density separation. These cells are very small in size (3-5 µm), have high nucleo-cytoplasmic ratio, and express nuclear Oct-4, cell surface protein SSEA-4, and other pluripotent markers such as Nanog, Sox-2, Rex-1, and Tert as indicated by immunolocalization and quantitative polymerase chain reaction (Q-PCR) studies. Interestingly, a distinct population of slightly larger, round hematopoietic stem cells (HSCs) with cytoplasmic Oct-4 were detected in the "buffy" coat, which usually gets banked or used during autologus stem cell therapy. Immunohistochemical studies on the umbilical cord tissue (UCT) sections (n=3) showed the presence of nuclear Oct-4-positive VSELs and many fibroblast-like mesenchymal stem cells (MSCs) with cytoplasmic Oct-4. These VSELs with nuclear Oct-4, detected in UCB, UCT, and discarded RBC fraction obtained after BM processing, may persist throughout life, maintain tissue homeostasis, and undergo asymmetric cell division to self-renew as well as produce larger progenitor stem cells, viz. HSCs or MSCs, which follow differentiation trajectories depending on the somatic niche. Hence, it can be concluded that the true stem cells in adult body tissues are the VSELs, whereas the HSCs and MSCs are actually progenitor stem cells that arise by asymmetric cell division of VSELs. The results of the present study may help explain low efficacy reported during adult autologous stem cell trials, wherein unknowingly progenitor stem cells are injected rather than the pluripotent stem cells with maximum regenerative potential.


Assuntos
Células da Medula Óssea/citologia , Células-Tronco Embrionárias/citologia , Sangue Fetal/citologia , Células-Tronco Pluripotentes/citologia , Antígenos de Diferenciação/metabolismo , Bancos de Sangue , Células da Medula Óssea/metabolismo , Separação Celular , Tamanho Celular , Células-Tronco Embrionárias/fisiologia , Células-Tronco Embrionárias/transplante , Humanos , Fator 3 de Transcrição de Octâmero/metabolismo , Células-Tronco Pluripotentes/fisiologia , Células-Tronco Pluripotentes/transplante , Medicina Regenerativa , Transplante Autólogo , Geleia de Wharton/citologia
7.
In Vitro Cell Dev Biol Anim ; 47(5-6): 406-19, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21614653

RESUMO

Human embryonic stem (hES) cells possess the ability to self-renew indefinitely and provide a potential source of differentiated progeny representing all three embryonic germ layers. Although hES cell lines share the expression of typical pluripotency markers, limited data is available regarding their differentiation capabilities. We have earlier reported the in-house derivation of two hES cell lines, KIND-1 and KIND-2 on human feeders. Here, we describe a comparative study carried out on both these cell lines to better understand the differentiation potential of KIND-1 and KIND-2 by gene expression analysis of representative gene transcripts reflecting pluripotency and the three germ layers viz. ectoderm, mesoderm, and endoderm. Gene expression analysis and immunolocalization studies were undertaken on (a) 7- and 14-d old embryoid bodies (EBs) (b) spontaneously differentiated cells from EBs, (c) cells derived from EBs under the influence of various growth factor treatments and (d) KIND-1 and KIND-2 cells co-cultured on mouse embryonic visceral endoderm-like feeder (END-2). Despite both the cell lines being XX, derived, passaged, and cultured similarly, KIND-1 exhibits preferential differentiation towards endodermal lineage whereas KIND-2 spontaneously forms beating cardiomyocytes. Perhaps the occurrence of discrete epigenetic profile in both the cell lines predisposes them to encompass different developmental potential in vitro. Our data provide evidence for existence of distinct differentiation propensity among hES cell lines and emphasizes the need to derive more hES cell lines for future regenerative medicine.


Assuntos
Diferenciação Celular , Linhagem Celular , Células-Tronco Embrionárias/citologia , Animais , Técnicas de Cultura de Células , Linhagem da Célula , Proliferação de Células , Corpos Embrioides/citologia , Corpos Embrioides/metabolismo , Células-Tronco Embrionárias/metabolismo , Humanos , Camundongos
8.
Stem Cells Dev ; 18(3): 435-45, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18699724

RESUMO

This study describes the successful derivation of two human embryonic stem (hES) cell lines using 53 frozen and 18 fresh "slow-growing" surplus embryos, obtained from collaborating in vitro fertilization clinics, on in-house-derived human feeder layers. The cell lines have been derived by whole embryo culture followed by further expansion of manually dissected inner cell mass from the surrounding trophoectodermal cells. Immunocytochemical localization of cell surface markers like SSEA-3, SSEA-4, TRA-1-60, and TRA-1-81, staining for alkaline phosphatase and reverse transcriptase polymerase chain reaction (RT-PCR) analysis of pluripotency state markers viz. Oct-4, TERT, Nanog, Rex1, and Sox2 indicate that both cell lines possess typical features of embryonic stem cells. Both cell lines exhibit normal female karyotype after 40 passages in culture. Pluripotent nature of the cell lines was confirmed both in vitro and in vivo. Embryoid bodies, formed in suspension culture, express markers for all three lineages as indicated by RT-PCR analysis for SOX 1 (ectoderm), HAND 1 (mesoderm), AFP (endoderm), and CDX2 (trophoectoderm). Teratoma formed in vivo in severe combined immunodeficient mice revealed cells of all the three embryonic germ layers. Comparison of the STR and human leukocyte antigen profiles of these cell lines with the existing human ES cell lines indicate that they are genetically distinct. The addition of our hES cell lines contributes usefully to the globally restricted repertoire of human ES cell lines.


Assuntos
Técnicas de Cultura de Células , Linhagem Celular , Células-Tronco Embrionárias/citologia , Animais , Diferenciação Celular , Células-Tronco Embrionárias/fisiologia , Feminino , Fibroblastos/citologia , Humanos , Cariotipagem , Camundongos , Camundongos SCID , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/fisiologia , Gravidez , Transplante de Células-Tronco , Teratoma/patologia
9.
Fertil Steril ; 84(4): 925-31, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16213845

RESUMO

OBJECTIVE: To determine the incidence of disomy and diploidy for chromosomes 18, X, and Y in the sperm samples of severe oligozoospermic (<5 x 10(6) spermatozoa/mL) and oligozoospermic (5-20 x 10(6) spermatozoa/mL) men undergoing intracytoplasmic sperm injection (ICSI) and to evaluate the influence of sperm aneuploidy on pregnancy outcome. DESIGN: Prospective study. SETTING: Infertility clinic and genetic laboratory. PATIENT(S): Fifteen patients with severe oligozoospermia, 15 patients with oligozoospermia, and 10 normal fertile donors. INTERVENTION(S): Fluorescence in-situ hybridization (FISH) performed on sperm samples. MAIN OUTCOME MEASURE(S): The frequency of disomy and diploidy for chromosomes 18, X, and Y was analyzed using FISH, and the clinical outcome after ICSI was correlated. RESULT(S): Significantly greater frequencies of XY, YY disomy and diploidy were observed in severe oligozoospermic men compared with oligozoospermic and normozoospermic men. Although the fertilization rate was similar, the pregnancy rate was higher in the group with oligozoospermia versus severe oligozoospermia. CONCLUSION(S): This study demonstrated the presence of an elevated sperm aneuploidy rate in patients with low semen quality. Additionally, the data show a negative influence of sperm chromosome abnormalities on ICSI outcome.


Assuntos
Aneuploidia , Oligospermia/genética , Resultado da Gravidez/genética , Injeções de Esperma Intracitoplásmicas/estatística & dados numéricos , Espermatozoides/fisiologia , Adulto , Distribuição de Qui-Quadrado , Feminino , Humanos , Hibridização in Situ Fluorescente/estatística & dados numéricos , Masculino , Oligospermia/epidemiologia , Gravidez , Resultado da Gravidez/epidemiologia , Taxa de Gravidez , Estudos Prospectivos
10.
Indian J Med Res ; 122(1): 34-42, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16106088

RESUMO

BACKGROUND & OBJECTIVE: Chromosomal anomalies have been postulated to be as one of the principal genetic factors in male infertility. Cytogenetic evaluation of men with severely compromised semen parameters reveals an increased incidence of chromosomal aberrations when compared with the normal population. The objective of this study was to determine the chromosomal constitution and sperm characteristics among Indian males with severe male factor infertility. METHODS: In this prospective study we investigated 88 infertile men (42 men with azoospermia and 46 men with sperm count <5 x 10(6) million/ml) prior to intracytoplasmic sperm injection (ICSI) treatment. Karyoptying was performed on peripheral blood lymphocytes according to standard methods. Polymerase chain reaction (PCR) was performed to screen the microdeletions in the AZF region of the Y chromosome. RESULTS: Constitutional chromosome abnormalities were identified in 14.3 per cent of azoospermic and 6.5 per cent of oligozoospermic men, with an overall rate of 10.2 per cent. Chromosomal abnormalities included gonosomal aberrations in 5 cases. Robertsonian translocation in one, trisomy 7 mosaicism in one case, deletion in chromosome 16 in one, and a marker chromosome in one case. Chromosome variants were observed in 33 (37.5%) subjects. Yqh- was the most frequent variant in sex chromosomes and increased length in heterochromatin and satellites were observed in autosomal chromosomes. INTERPRETATION & CONCLUSION: The high rate of chromosomal anomalies among infertile men strongly suggests the need for routine cytogenetic analysis prior to employment of assisted reproduction techniques. In addition, meticulous follow-up of babies born after ICSI, especially male offsprings, is necessary.


Assuntos
Aberrações Cromossômicas/estatística & dados numéricos , Infertilidade Masculina/genética , Oligospermia/genética , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
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