Apoptotic mechanisms of myricitrin isolated from Madhuca longifolia leaves in HL-60 leukemia cells

Abstract Background: Myricitrin, a naturally occurring flavonoid in Madhuca longifolia, possesses several medicinal properties. Even though our earlier work revealed its role against the proliferation of acute myelogenous leukemia cells (HL-60), its molecular mechanisms have not yet been revealed. The current study aims to explore the molecular mechanisms of myricitrin (isolated from an ethnomedicinal drug Madhuca longifolia) to induce apoptosis in HL-60 cells. Methods and Results: Treatment with IC-50 dose of myricitrin (353 µM) caused cellular shrinkage and cell wall damage in HL-60 cells compared to untreated control cells. Myricitrin treatment reduced the mitochondrial membrane potential (22.95%), increased DNA fragmentation (90.4%), inhibited the cell survival proteins (RAS, B-RAF, & BCL-2) and also induced pro-apoptotic proteins (p38, pro-caspase-3, pro-caspase-9 and caspase-3) in the HL-60 cells. Conclusions: The present study provides scientific evidence for the apoptosis caused by myricitrin in HL-60 leukemia cells. Hence, the phytochemical myricitrin could be considered as a potential candidate to develop an anticancer drug after checking its efficacy through suitable pre-clinical and clinical studies.

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Ferritin-Conjugated Antibody for the Demonstration of Isoantigens on the Surface of Murine Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099982 ◽

1968 ◽

Vol 26 ◽

pp. 48-49

Author(s):

T. Aoki ◽

J. Izard ◽

U. Hämmerling ◽

E. de Harven ◽

L. J. Old

Keyword(s):

Cell Surface ◽

Gamma Globulin ◽

Leukemia Cells ◽

Labelling Technique ◽

Direct Labelling ◽

Labelling Method

Although a variety of viral and cellular antigens have been demonstrated by ferritin-labeled antibody, this technique has not been used to locate isoantigens on the surface of nucleated cells. The recognition of several systems of isoantigens on the surface of thymocytes, lymphocytes and leukemia cells of the mouse and the ease with which these cells can be obtained in free suspension led us to consider the ferritin-labelling method to determine the amount and location of these isoantigens on the cell surface. Because of the problems involved in the direct labelling of mouse gamma globulin by ferritin, we have chosen an indirect labelling technique (i.e. ferritin-conjugated rabbit anti mouse γG)to detect localization of mouse isoantibody.

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The distribution of antigen on the surface of RBL-2H3 rat basophilic leukemia cells observed by back-scattered electron imaging

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142992 ◽

1986 ◽

Vol 44 ◽

pp. 274-275

Author(s):

R.F. Stump ◽

J.R. Pfeiffer ◽

JC. Seagrave ◽

D. Huskisson ◽

J.M. Oliver

Keyword(s):

Cell Surface ◽

Dynamic Properties ◽

Leukemia Cells ◽

Antigen Binding ◽

Scattered Electron ◽

Ige Receptor ◽

Receptor Complexes ◽

Rat Basophilic Leukemia Cells ◽

Electron Imaging ◽

Basophilic Leukemia

In RBL-2H3 rat basophilic leukemia cells, antigen binding to cell surface IgE-receptor complexes stimulates the release of inflammatory mediators and initiates a series of membrane and cytoskeletal events including a transformation of the cell surface from a microvillous to a lamellar topography. It is likely that dynamic properties of the IgE receptor contribute to the activation of these responses. Fewtrell and Metzger have established that limited crosslinking of IgE-receptor complexes is essential to trigger secretion. In addition, Baird and colleagues have reported that antigen binding causes a rapid immobilization of IgE-receptor complexes, and we have demonstrated an apparent increase with time in the affinity of IgE-receptor complexes for antigen.

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Involvement of GER in Friend leukemia virus assembly in high-pressure frozen cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160509 ◽

1990 ◽

Vol 48 (3) ◽

pp. 590-591

Author(s):

W. Djaczenko ◽

M. Müller ◽

A. Benedetto ◽

G. Carbone

Keyword(s):

High Pressure ◽

Virus Assembly ◽

Leukemia Virus ◽

Leukemia Cells ◽

Serial Sections ◽

Myeloma Cells ◽

Virus Particles ◽

Friend Leukemia ◽

Carbon Coated ◽

Friend Leukemia Virus

A thickening of ER membranes in murine myeloma cells was attributed by de Harven to the assembly of intracisternal virus particles. We observed similar thickening of GER membranes in Friend leukemia cells (FLC) apparently associated with Friend leukemia virus (FLV) assembly. We reinvestigated the problem of GER involvement in FLV assembly using high pressure cryofixed FLC.FLC (745A clone growing in suspension and FF clone growing in monolayer) were immersed in Hexadecene (Fluka, Switzerland) and rapidly frozen in Balzers HPM 010 freezing machine working at 2200 bar. All cells were freeze substituted at -90°C in 2% OsO4 in absolute acetone. Serial sections cut to avoid misinterpretations due to the geometry of sections, were collected on carbon coated 100 mesh grids.

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