Activator protein-1 (AP-1) transcription factor is a key component of many signal transduction pathways involved in the regulation of cellular processes and controls rapid responses of mammalian cells when exposed to the variety of stimulus. The phorbol 12-myristate 13-acetate and Forskolin (Fo) are well-known kinase activators/stimulators of Protein Kinase C (PKC) and Protein Kinase A (PKA) respectively. Importantly, these kinases are found to be present in transitional points of many cell signaling pathways, especially those involved in proliferation.
View Article and Find Full Text PDFChoriocarcinoma, a trophoblastic neoplasia, occurs in women as an incidence of abnormal pregnancy. BeWo choriocarcinoma cells derived from the abnormal placentation are a suitable model system to study the factors associated with differentiation, invasion and other cellular events as an alternative to clinical samples. Many protein kinases orchestrate the complex events of cell cycle and in case of malignancy such regulators are found to be mutated.
View Article and Find Full Text PDFThe production of inflammatory mediators by epithelial cells in inflammatory lung diseases may represent an important target for the anti-inflammatory effects of glucocorticoids. Activator protein-1 is a major activator of inflammatory genes and has been proposed as a target for inhibition by glucocorticoids. We have used human pulmonary type-II A549 cells to examine the effect of dexamethasone on the phorbol ester (PMA)/Lipopolysaccharide (LPS) induced pro-inflammatory cytokines and AP-1 factors.
View Article and Find Full Text PDFThe loss of bone mass and alteration in bone physiology during space flight are one of the major health risks for astronauts. Although the lack of weight bearing in microgravity is considered a risk factor for bone loss and possible osteoporosis, organisms living in space are also exposed to cosmic radiation and other environmental stress factors. As such, it is still unclear as to whether and by how much radiation exposure contributes to bone loss during space travel, and whether the effects of microgravity and radiation exposure are additive or synergistic.
View Article and Find Full Text PDFEnergetic protons are the most abundant particle type in space and can pose serious health risks to astronauts during long-duration missions. The health effects of proton exposure are also a concern for cancer patients undergoing radiation treatment with accelerated protons. To investigate the damage induced by energetic protons in vivo to radiosensitive organs, 6-week-old BALB/c male mice were subjected to 250 MeV proton radiation at whole-body doses of 0.
View Article and Find Full Text PDFIn space, living organisms are exposed to multiple stress factors including microgravity and space radiation. For humans, these harmful environmental factors have been known to cause negative health impacts such as bone loss and immune dysfunction. Understanding the mechanisms by which spaceflight impacts human health at the molecular level is critical not only for accurately assessing the risks associated with spaceflight, but also for developing effective countermeasures.
View Article and Find Full Text PDFAndrogen receptor (AR) signaling axis plays a vital role in the development of prostate and critical in the progression of prostate cancer. Androgen withdrawal initially regresses tumors but eventually develops into aggressive castration-resistant prostate cancer (CRPC). Activator Protein-1 (AP-1) transcription factors are most likely to be associated with malignant transformation in prostate cancer.
View Article and Find Full Text PDFCadmium (Cd) is one of the well-known highly toxic environmental and industrial pollutants. Cd first accumulates in the nucleus and later interacts with zinc finger proteins of antiapoptotic genes and inhibit the binding of transcriptional factors and transcription. However, the role of Cd in oxidative stress and apoptosis is less understood.
View Article and Find Full Text PDFSteroid hormones and their nuclear receptors play a major role in the development and progression of breast cancer. MCF-7 cells are triple-positive breast cancer cells expressing estrogen receptor (ER), progesterone receptor (PR), and glucocorticoid receptor (GR). However, interaction and their role in expression pattern of activator protein (AP-1) transcription factors (TFs) are not completely understood.
View Article and Find Full Text PDFSingle wall carbon nanotubes due to their unique structural and electronic characteristics have revolutionized the field of nanotechnology and are widely used the field of transistors, drug delivery, and nanocomposities. For improved efficiency of these applications, the utilized tubes must of preeminent purity. Here, we report key parameters that are optimized to achieve their highest purity upto 98 wt%, and yield as high as 50 wt% by thermal and chemical oxidation.
View Article and Find Full Text PDFThe increased applications of carbon nanotubes in the field of drug delivery, bioimaging and biosensors demand nanotubes to be of highest purity, free from metallic impurities and amorphous carbon. All of these sectors require a profound investigation about the toxic effects on human and the environment. Many attempts have been made to purify and surface modify the carbon nanotubes, however a detailed study on the raw and purified material has yet to be conducted.
View Article and Find Full Text PDFApigenin is one of the plant flavonoids present in fruits and vegetables, acting as an important nutraceutical component. It is recognized as a potential antioxidant, antimicrobial, and anti-inflammatory molecule. In the present study, the mechanism of anti-inflammatory action of apigenin on lipopolysaccharide (LPS)-induced pro-inflammatory cytokines and activator protein-1 (AP-1) factors in human lung A549 cells was investigated.
View Article and Find Full Text PDFAcute and chronic alveolar or bronchial inflammation is thought to be central to the pathogenesis of many respiratory disorders. Cytokines and granulocyte macrophage colony-stimulating factors (GM-CSF) play an important role in chronic inflammation. Activator protein-1 (AP-1) the superfamily of transcription factors is involved in proliferation, differentiation, apoptosis, and transformation including inflammation.
View Article and Find Full Text PDFIn this work we report the improved performance an electrochemical glucose sensor based on a glassy carbon electrode (GCE) that has been modified with highly purified single wall carbon nanotubes (SWCNTs) dispersed in polyethyleneimine (PEI), polyethylene glycol (PEG) and polypyrrole (PPy). The single wall carbon nanotubes were purified by both thermal and chemical oxidation to achieve maximum purity of ~98% with no damage to the tubes. The SWCNTs were then dispersed by sonication in three different organic polymers (1.
View Article and Find Full Text PDFProton particles comprise the most abundant ionizing radiation (IR) in outer space. These high energy particles are known to cause frequent double- and single-stranded DNA lesions that can lead to cancer and tumor formation. Understanding the mechanism of cellular response to proton-derived IR is vital for determining health risks to astronauts during space missions.
View Article and Find Full Text PDFThe activated transcription factor ERα plays an important role in the breast development and progression of cancer. In a non-classical pathway ER interacts with other transcription factors AP-1, NFkB, SP1, etc. AP-1 transcription factors control rapid responses of mammalian cells to stimuli that impact proliferation, differentiation, and transformation.
View Article and Find Full Text PDFWith the advent of nanotechnology, many methods of synthesis of nanoparticles have come into practice and the 'polymer mediated growth' technique is among them. In this route, ions of one of the reactants are allowed to diffuse from an external solution into a polymer matrix where the other reactant is complexed and bound. The exact role of ionic diffusion in the formation of nanoparticles was investigated in the current study by studying the patterns of kinetics of nanoparticle formation using UV vis spectroscopy.
View Article and Find Full Text PDFThere is an ongoing concern regarding the biocompatibility of nanoparticles with sizes less than 100 nm as compared to larger particles of the same nominal substance. In this study, we investigated the toxic properties of magnetite stabilized with polyacrylate sodium. The magnetite was characterized by X-ray powder diffraction analysis, and the mean particle diameter was calculated using the Scherrer formula and was found to be 9.
View Article and Find Full Text PDFThe synthesis of nanoparticles and their functionalization to effectively utilize them in biological applications including drug delivery is currently a challenge. Calcium carbonate among many other inorganic nanosized particles offers promising results for such applications. We have synthesized calcium carbonate nanoparticles using polymer mediated growth technique, where one of the ions bound within polymer matrix and the other diffuses and reacts to form desired compound.
View Article and Find Full Text PDFAlthough radiation related research has been conducted extensively, the molecular toxicology and cellular mechanisms affected by proton radiation remain poorly understood. We recently reported that the high energy protons induce cell death through activation of apoptotic signaling genes; caspase 3 and 8 (Baluchamy et al. J Biol Chem 285:24769-24774, 2010).
View Article and Find Full Text PDFHere, we have synthesized Zinc Oxide (ZnO) nanorods at room temperature using zinc acetate and hexamethylenetetramine as precursors followed by characterization using X-ray diffraction (XRD), fourier transform infra red spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy. The growth of the synthesized ZnO was found to be very close to its hexagonal nature, which is confirmed by XRD. The nanorods were grown perpendicular to the long-axis and grew along the [001] direction, which is the nature of ZnO growth.
View Article and Find Full Text PDFThis study explores the changes in expression of microRNA (miRNA) and related genes under simulated microgravity conditions. In comparison with static 1 × g, microgravity has been shown to alter global gene expression patterns and protein levels in cultured cells or animals. miRNA has recently emerged as an important regulator of gene expression, possibly regulating as many as one-third of all human genes.
View Article and Find Full Text PDFWith the widespread application of carbon nanotubes (CNTs) in diverse commercial processes, scientists are now concerned about the potential health risk of occupational exposures. In this study, CNT-induced pulmonary toxicity was investigated by exposing BALB/c mice to aerosolized single-wall (SW) CNT and multiwall (MW) CNT (5 μg/g of mice) for 7 consecutive days in a nose-only exposure system. Microscopic studies showed that inhaled CNTs were homogeneously distributed in the mouse lung.
View Article and Find Full Text PDFOur previous report on multiwall carbon nanotubes (MWCNT) has demonstrated the generation of reactive radicals and depletion of intracellular antioxidants which in turn cause cell death through activation of caspases. The molecular mechanism of cellular death due to MWCNT is not clear yet. In this study, we investigated the signaling pathways implicated in MWCNT-induced apoptosis in rat lung epithelial cells.
View Article and Find Full Text PDFIn Vitro Cell Dev Biol Anim
September 2010
Radiation is known to potentially interfere with cellular functions at all levels of cell organization. The radiation-induced stress response is very complex and involves altered expression of many genes. Identification of specific genes may allow the determination of pathways important in radiation responses.
View Article and Find Full Text PDF