Microparticles are submicron vesicles shed from plasma membranes in response to cell activation, injury and/or apoptosis. Microparticles of various cellular origins, such as platelets, leukocytes, and endothelial cells, are found in the plasma of healthy subjects, and their amount increases under pathological conditions. Recent studies show that endothelial microparticles, a kind of envelope particles derived from endothelial cells, not only constitute a marker of endothelial dysfunction, but also play a major biological role in the diagnostic and therapeutic approaches to erectile dysfunction.
Biomarkers ; Cell Membrane ; Endothelial Cells ; metabolism ; pathology ; Erectile Dysfunction ; metabolism ; pathology ; Humans ; Liposomes ; metabolism ; Male

OBJECTIVETo observe the change in the amount of sialic acids on hepatocellular carcinoma (HCC) cell membrane.

METHODSSurgical specimens of HCC and liver cirrhosis tissues were obtained from 28 patients to prepare carcinoma cell and hepatocyte suspensions by collagenase digestion. For assay of α2, 3 and α2, 6-sialic acids, the cells were suspended in the staining buffer containing either fluorescein isothiocyanate-Maackia amurensis lectin (FITC-MAL) or fluorescein isothiocyanate-Sambucus nigra bark lectin (FITC-SNA) and incubated for 1 h, respectively. Flow cytometric analysis was carried out to measure the mean fluorescence intensity (MFI) on the cell surface.

RESULTSIn both FITC-MAL- and FITC-SNA-incubated HCC cells, the MFI on the cell surface was greater than that of the hepatocytes.

CONCLUSIONBoth of α2, 3 and α2, 6- sialic acids increases significantly on the hepatocyte membrane after the carcinomatous change.

Carcinoma, Hepatocellular ; metabolism ; pathology ; Cell Membrane ; metabolism ; Humans ; Liver Cirrhosis ; metabolism ; pathology ; Liver Neoplasms ; metabolism ; pathology ; Sialic Acids ; metabolism

OBJECTIVETo investigate the expression of cell surface E-cadherin in leukemia cell and the correlation of cell membrane localization of beta-catenin with E-cadherin expression.

METHODSBone marrow samples from 46 patients with acute leukemia and 17 normal donors were analyzed. Cell surface expression of E-cadherin and membrane localization of beta-catenin were labeled by immunofluorescence and analyzed with a laser scanning confocal fluorescence microscope in 14 specimens.

RESULTSCell surface E-cadherin expression level was significantly lower in leukemia cells (with the median fluorescent intensity of 16.78) than in normal hematopoietic progenitors (26.03). Correlation analysis showed that cell membrane localization of beta-catenin was correlated with E-cadherin expression (r = 0.74, P = 0.002). After E-cadherin was induced to express in leukemic cell by 5-Aza-CdR, membranous expression of beta-catenin was elevated while the nuclear expression reduced, indicating that E-cadherin-mediated adhesions could recruit beta-catenin to cell membrane.

CONCLUSIONThe loss of E-cadherin in leukemia cells may result in beta-catenin translocating to the nuclear and transcriptional activation of its target genes.

Cadherins ; metabolism ; Case-Control Studies ; Cell Membrane ; metabolism ; Humans ; Leukemia ; metabolism ; pathology ; beta Catenin ; metabolism

Research on peripheral nervous injuries, especially the stretched injuries, is important to improve the clinical effectiveness and alleviate the patients's pain. In recent years, the biological changes and mechanics of stretched axons have been hot topics. This article reviews the recent advances in the morphological changes of axons as well as changes in cellular membrane, cytoskeleton, cellular metabolism, and action potential after axonal stretch.
Action Potentials ; Animals ; Axons ; metabolism ; pathology ; Cell Membrane ; pathology ; Cytoskeleton ; pathology ; Humans ; Stress, Mechanical

Animals ; Arthritis, Experimental ; metabolism ; pathology ; Breast Neoplasms ; pathology ; Cadherins ; metabolism ; physiology ; Cell Movement ; Female ; Fibroblasts ; cytology ; pathology ; Humans ; Macrophages ; cytology ; pathology ; Neoplasm Invasiveness ; Synovial Membrane ; cytology ; metabolism ; pathology

OBJECTIVETo investigate the opening of the mitochondrial permeability transition pores of the cultured hepatocytes in a non-alcoholic fatty liver disease model and its relationship with apoptosis of the cells.

METHODSOleic acid was used to induce cultured L02 hepatocyte steatotic in making a model of NAFLD. The steatotic hepatocytes were detected with oil red O staining; the opening of the mitochondrial permeability transition pores was observed under a fluorescence microscope. The apoptosis of the cells was detected with a flow cytometer.

RESULTSAfter adding oleic acid to the cultured hepatocytes, a model of steatosis of human hepatocytes was established after 24 hours. Oleic acid opened the mitochondrial permeability transition pores of the L02 hepatocytes (72.58%+/-2.78%) more than that in the control group (8.28%+/-4.98%) and the difference was statistically significant (P < 0.01). Apoptosis index of the steatotic hepatocytes at 24 hours and 48 hours were 11.09%+/-4.95% and 15.24%+/-2.45%. They were also higher than those of the control group (4.56%+/-1.25%) (P < 0.05, P < 0.01).

CONCLUSIONOpening the mitochondrial permeability transition pores may be the basis of the apoptosis of steatotic hepatocytes in vitro, and it also may be related to the steatosis of NAFLD in human beings.

Apoptosis ; Cell Line ; Fatty Liver ; metabolism ; pathology ; Hepatocytes ; metabolism ; Humans ; Mitochondria, Liver ; metabolism ; Mitochondrial Membrane Transport Proteins ; metabolism

OBJECTIVETo detect the cell-surface-expressed nucleolin and investigate its tumor suppressing effect on the growth of hepatocellular carcinoma cells.

METHODSTo detect cell-surface-expressed nucleolin in the hepatocellular carcinoma cells by immunofluorescence and flow cytometry. To down-regulate the nucleolin expression level in hepatocellular carcinoma cells by RNA interference. The tumor-suppressing effect of cell-surface nucleolin on hepatocellular carcinoma cells was assessed by MTT and transwell chamber assays.

RESULTSNucleolin was expressed in the nuclei, cytoplasm and on the cell surface of hepatocellular carcinoma cells. ShRNA markedly decreased the nucleolin expression level in the cytoplasm and on the cell surface (P < 0.01), but the nuclear nucleolin remained unchanged. After downregulation of cell-surface nucleolin, MTT assays showed that the cell growth rate of hepatocellular carcinoma cells in the shRNA interference group was significantly inhibited as compared with that in the control group (P < 0.01). The transwell chamber assay showed that the mean transmembrane cell number in the shRNA interference group was significantly lower than that in the control group.

CONCLUSIONThe results of this study show that downregulation of cell-surface nucleolin expression inhibits the growth of hepatocellular carcinoma cells in vitro.

Carcinoma, Hepatocellular ; genetics ; metabolism ; pathology ; Cell Line, Tumor ; Cell Membrane ; metabolism ; Cell Movement ; Cell Nucleus ; metabolism ; Cell Proliferation ; Cytoplasm ; metabolism ; Down-Regulation ; Humans ; Liver Neoplasms ; genetics ; metabolism ; pathology ; Phosphoproteins ; metabolism ; RNA Interference ; RNA, Small Interfering ; pharmacology ; RNA-Binding Proteins ; metabolism

OBJECTIVETo investigate the influence of hypoxia induced microtubule damage on the opening of mitochondrial permeable transition pore (MPTP)of cardiac myocytes and on the decrease of respiratory function in rat.

METHODSPrimary cultured myocardial cells from 30 neonatal rats were randomized as normoxic group (A), hypoxia group (B), normoxia with microtubule destabilizing agent group (C, with treatment of 8 micromol/L colchicines for 30 minutes before normoxia), and hypoxia with microtubule stabilizing agent group (D, with treatment of 10 micromol/L taxol for 30 minutes before hypoxia). beta-tubulin immunofluorescence ,the opening of mitochondria permeability transition pore, and the mitochondrial inner membrane potential were detected at 0.5, 1, 3, 6 and 12 post-treatment hours (PTH), and the mitochondrial respiratory function was determined by MTT method. The changes in these indices were also determined in A group at the corresponding time-points.

RESULTSObvious damage of polymerized microtubule, opening of MPTP, mitochondrial inner membrane potential loss and decrease of myocardial respiratory activity were observed in both group B and C at 0.5 PTH, and they became more and more serious afterwards. However, the changes in the above indices in D group were much better than those in B group (P < 0.05 or 0.01), and no difference was found between D (92.8 +/- 4.0)% and C [(100.0 +/- 0.0) %, P > 0.05] groups.

CONCLUSIONHypoxia played a role in the myocardial microtubule damage as well as in the opening of MPTP. Moreover, hypoxia could also impair the mitochondrial respiratory function. Microtubule destabilizing agent could reproduce well the process of hypoxia induced microtubule damage, while the stabilizing agent exerted protective effect by improving the transition of mitochondrial permeability and the mitochondria respiratory function.

Animals ; Cell Hypoxia ; Cells, Cultured ; Hypoxia ; metabolism ; pathology ; Membrane Potential, Mitochondrial ; Microtubules ; pathology ; Mitochondria, Heart ; metabolism ; pathology ; Myocytes, Cardiac ; metabolism ; pathology ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo detect the expression of macrophage inflammatory protein-1alpha (MIP-1alpha), a disintegrin-like and metalloproteinase (ADAM) 8 and 12 and CD68 protein in giant cell lesions of jaw and giant cell tumors of long bone, and to study their effects on the histogenesis of giant cells in such lesions.

METHODSMIP-1alpha, ADAM8, ADAM12 and CD68 were detected by immunohistochemistry in 24 paraffin-embedded specimens of central giant cell lesions of jaw and giant cell tumors respectively.

RESULTSMIP-1alpha positive signal was located in blood vessels and bone. ADAM8, ADAM12 and CD68 positive signals were located in the cell membrane and cytoplasm of all multinucleated giant cells and some round mononuclear cells in the lesions. In addition, some spindle mononuclear stromal cells were positive for ADAM12 in both lesions.

CONCLUSIONMultinucleated giant cells probably originate from CD68-postive round mononuclear cells, which are recruited from monocyte-macrophage system by chemokines, such as MIP-1alpha, followed by cell fusion mediated by ADAM8 and ADAM12.

ADAM Proteins ; metabolism ; ADAM12 Protein ; Antigens, CD ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; Bone Neoplasms ; metabolism ; pathology ; Cell Membrane ; metabolism ; Chemokine CCL3 ; Chemokine CCL4 ; Cytoplasm ; metabolism ; Giant Cell Tumor of Bone ; metabolism ; pathology ; Giant Cells ; metabolism ; Granuloma, Giant Cell ; metabolism ; pathology ; Humans ; Jaw Diseases ; metabolism ; pathology ; Macrophage Inflammatory Proteins ; metabolism ; Membrane Proteins ; metabolism

OBJECTIVETo examine the cellular components at different stages of the crescent formation in four most common types of human crescentic glomerulonephritis (CGN), including anti-GBM disease (GBM-CGN), crescentic IgA nephropathy (IgA-CGN), ANCA associated pauci-immune CGN (ANCA-CGN) and crescentic lupus glomerulonephritis (LN-CGN).

METHODSRenal biopsy specimens of patients with GBM-CGN (n = 10), IgA-CGN (n = 12), ANCA-CGN (n = 12), and LN-CGN (n = 11) were selected. Immunohistochemistry was adopted to identify the cellular components using different cell markers including cytokeratin (PEC), CD68 (macrophage), nestin (podocyte), podocalyxin (podocyte), CD3 (lymphocyte), CD15 (neutrophil) and PCNA.

RESULTSThere were different subtypes of cell components identified during the formation of a cellular crescent in 4 different types of human CGN. Mainly of PEC 11.4 (0.0, 95.0)%, macrophage 8.0 (0.0, 35.0)% and podocyte 5.5 (0.0, 22.0)% and their constitutive percentages were different among various CGNs (P < 0.01). In all the CGNs studied, there were 50% of cells were negative to all the cell markers adopted for this expeiment. Podocalyxin positive cells 0.5 (0.0, 9.6)% were significantly less than nestin positive cells 5.5 (0.0, 22.0)% in all CGNs. PCNA positive cells were 44.7 (16.7, 83.3)% in the cellular crescent of all CGNs and co-localized with nestin (38/45 cases), CK (42/45 cases) or CD68 (24/45 cases).

CONCLUSIONSPEC, macrophage and podocyte might play important roles in the formation of crescents. The staining disparity of nestin and podocalyxin indicates that podocyte dedifferentiation may occur during the crescent formation. PEC, podocytes and macrophages may participate in the formation of crescent in common CGNs through active cellular proliferation.

Anti-Glomerular Basement Membrane Disease ; metabolism ; pathology ; Antibodies, Antineutrophil Cytoplasmic ; metabolism ; Antigens, CD ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; Cell Proliferation ; Epithelial Cells ; metabolism ; pathology ; Glomerulonephritis ; classification ; metabolism ; pathology ; Glomerulonephritis, IGA ; metabolism ; pathology ; Humans ; Intermediate Filament Proteins ; metabolism ; Keratins ; metabolism ; Lupus Nephritis ; metabolism ; pathology ; Macrophages ; metabolism ; pathology ; Nerve Tissue Proteins ; metabolism ; Nestin ; Podocytes ; metabolism ; pathology ; Proliferating Cell Nuclear Antigen ; metabolism ; Sialoglycoproteins ; metabolism