Thanks to the increasing use of flow cytometry in research in veterinary spermatology, many new membrane integrity assays have been developed over the past decade. These assays are important because of their superior ability to forecast fertility when compared with other tests, such as sperm motility. This major component of the sperm quality assessment has generated new investigations with the aim of developing tests that can detect membrane damage in a very early state. Using phospholipid transposition tests, early changes in membrane permeability and fluidity can be assessed in a large number of spermatozoa using fluorescent probes in combination with flow cytometry.
Andrology ; methods ; Animals ; Cell Membrane ; physiology ; Cell Membrane Permeability ; physiology ; Cryopreservation ; methods ; Male ; Phospholipids ; metabolism ; Spermatozoa ; cytology ; metabolism ; ultrastructure ; Veterinary Medicine ; methods

OBJECTIVETo observe the ultracytochemical localization of H(+)-adenosine triphosphatase (H(+)-ATPase) in the cell organelles.

METHODSThe localization of H(+)-ATPase in the cell organelles was observed in the hepatocytes and renal cells of Wistar rats using routine ultracytochemical methods.

RESULTSH(+)-ATPase activities were observed on the lysosomal membrane and nuclear envelope of the hepatocytes and proximal tubule epithelial cells of the nephron in Wistar rats.

CONCLUSIONThis finding supports the hypothesis that H(+)-ATPase (V-ATPase) is present on the plasma membrane and in the endomembrane system.

Animals ; Cell Membrane ; enzymology ; Hepatocytes ; cytology ; enzymology ; ultrastructure ; Histocytochemistry ; methods ; Kidney ; cytology ; enzymology ; ultrastructure ; Lysosomes ; enzymology ; Male ; Organelles ; enzymology ; Rats ; Rats, Wistar ; Vacuolar Proton-Translocating ATPases ; metabolism

E-cadherin is a cell adhesion molecule that plays an important role in maintaining renal epithelial polarity and integrity. The purpose of this study was to determine the exact cellular localization of E-cadherin in pig kidney. Kidney tissues from pigs were processed for light and electron microscopy immunocytochemistry, and immunoblot analysis. E-cadhedrin bands of the same size were detected by immunoblot of samples from rat and pig kidneys. In pig kidney, strong E-cadherin expression was observed in the basolateral plasma membrane of the tubular epithelial cells. E-cadherin immunolabeling was not detected in glomeruli or blood vessels of pig kidney. Double-labeling results demonstrated that E-cadherin was expressed in the calbindin D28k-positive distal convoluted tubule and H(+)-ATPase-positive collecting duct, but not in the aquaporin 1-positive, N-cadherin-positive proximal tubule. In contrast to rat, E-cadherin immunoreactivity was not expressed at detectable levels in the Tamm-Horsfall protein-positive thick ascending limb of pig kidney. Immunoelectron microscopy confirmed that E-cadherin was localized in both the lateral membranes and basal infoldings of the collecting duct. These results suggest that E-cadherin may be a critical adhesion molecule in the distal convoluted tubule and collecting duct cells of pig kidney.
Animals ; Blotting, Western/veterinary ; Cadherins/*genetics/metabolism ; Cell Membrane/*metabolism/ultrastructure ; *Gene Expression Regulation ; Kidney/*metabolism ; Male ; Microscopy, Electron, Transmission/veterinary ; Sus scrofa/*genetics/metabolism

Mitochondrial biogenesis is known to accompany adipogenesis to complement ATP and acetyl-CoA required for lipogenesis. Here, we demonstrated that mitochondrial proteins such as ATP synthase alpha and beta, and cytochrome c were highly expressed during the 3T3-L1 differentiation into adipocytes. Fully-differentiated adipocytes showed a significant increase of mitochondria under electron microscopy. Analysis by immunofluorescence, cellular fractionation, and surface biotinylation demonstrated the elevated levels of ATP synthase complex found not only in the mitochondria but also on the cell surface (particularly lipid rafts) of adipocytes. High rate of ATP (more than 30 micrometer) synthesis from the added ADP and Pi in the adipocyte media suggests the involvement of the surface ATP synthase complex for the exracellular ATP synthesis. In addition, this ATP synthesis was significantly inhibited in the presence of oligomycin, an ATP synthase inhibitor, and carbonyl cyanide m-chlorophenylhydrazone (CCCP), an ATP synthase uncoupler. Decrease of extracellular ATP synthesis in acidic but not in basic media further indicates that the surface ATP synthase may also be regulated by proton gradient through the plasma membrane.
Adenosine Triphosphate/analysis/*biosynthesis ; Adipocytes/*enzymology/ultrastructure ; Animals ; Cell Differentiation/physiology ; Cell Membrane/chemistry ; Cells, Cultured ; Humans ; Membrane Microdomains/chemistry/*enzymology ; Mice ; Mitochondria/metabolism/ultrastructure ; Mitochondrial Proton-Translocating ATPases/analysis/*physiology ; Research Support, Non-U.S. Gov't

OBJECTIVETo investigate the role of mitofusin-2 gene (mfn2) in apoptosis in human breast carcinoma cell line MCF-7 cells after in vitro transfection.

METHODSpEGFP mfn2 was transfected by sofast in vitro. Expression of GFP was observed by Western blot, and the MCF-7 cell proliferation was measured by MTT and cell counting. Apoptosis in MCF-7 cells was observed in annexin-V/PI and chondrosome transmembrane potential of MCF-7 marked in JC-1 by FCM. The Ultrastructure of cells was observed by transmission electron microscopy.

RESULTSThe stable expression of GFP in MCF-7 cells was confirmed by Western blot. Mfn2 significantly inhibited cell proliferation, revealed by MTT, and decrease chondrosome transmembrane potential. Exogenous mfn2 gene significantly induced apoptosis. The apoptotic rate was increased from 3.6% to 16.0% (P < 0.05). Mfn2 gene induced break down and loss of mitochondrial cristae, and rarefaction of mitochondrial ground substance. Swollen mitochondria intensely aggregated around the cell nuclei.

CONCLUSIONMfn2 can strongly induce apoptosis in MCF-7 cells, which may be associated with decrease of mitochondrial transmembrane potential.

Apoptosis ; Breast Neoplasms ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; Female ; GTP Phosphohydrolases ; Green Fluorescent Proteins ; genetics ; metabolism ; Humans ; Membrane Potential, Mitochondrial ; Membrane Proteins ; genetics ; metabolism ; Mitochondria ; ultrastructure ; Mitochondrial Proteins ; genetics ; metabolism ; Plasmids ; Recombinant Proteins ; genetics ; metabolism ; Transfection

OBJECTIVETo determine the location on outer envelope and natural antibody response and types of genus-specific lipoprotein antigen LipL41s in patients with Leptospira interrogans.

METHODSMicroscope agglutination test (MAT) was used to examine leptospirosis patients' serum samples from Sichuan area, China. Ni-NTA affinity chromatography was performed to extract the target recombinant rLipL41/1 and rLipL41/2 products that expressed under inducement of IPTG. Western blot assay was performed to detect the immunoreactivity between the sera from the patients infected with different serogroups of L. interrogans and rLipL41s. Immune aurosol electron microscopy was selected to locate the position of LipL41s on leptospiral envelope. ELISA based on rLipL41s was established to confirm the level and types of specific antibody.

RESULTSL. interrogans serogroup icterohaemorrhagiae remained to be the most dominant leptospiral serogroup in Sichuan area. All the sera from patients infected with different serogroups of L. interrogans could efficiently recognize the LipL41s which were the protein molecular that located on the external surface of leptospiral envelope. In the 156 serum samples from MAT positive leptospirosis patients, the positive rates for rLipL41/1 or rLipL41/2 specific IgM appeared to be 84.6%-87.8% and 78.2%-83.3%, respectively, while for rLipL41/1 or rLipL41/2 specific IgG they were 69.2%-81.4% and 75.0%-80.1%, respectively.

CONCLUSIONLipL41s were the leptospiral superficial protein antigen of L. interrogans. Both the LipL41/1 and LipL41/2 could induce serum antibodies IgM and IgG with extensive antigenic-cross reaction during natural infection of L. interrogans in general populations. Hence, rLipL41/1 or rLipL41/2 could be used as the antigen candidate for developing universal genetic engineering vaccine and detection kit.

Antibodies, Bacterial ; blood ; immunology ; Antigens, Bacterial ; metabolism ; Bacterial Outer Membrane Proteins ; metabolism ; Cell Membrane ; metabolism ; Cross Reactions ; Humans ; Immunoglobulin G ; blood ; immunology ; Immunoglobulin M ; blood ; immunology ; Leptospira interrogans ; metabolism ; ultrastructure ; Leptospirosis ; immunology ; Species Specificity

OBJECTIVETo determine the relationship of thick greasy tongue fur formation and permeability of vascular endothelial cells (ECs) with the protein expression of zonula occludens-1 (ZO-1).

METHODSSprague Dawley rats were randomly divided into a model group of severe acute pancreatitis (SAP) and a sham-operated (SO) group. The SAP rats were further divided into two subgroups on the basis of tongue-coating status: a thick greasy tongue fur group (SAP-TGF) and a normal tongue fur group (SAP-NF). Six rats were chosen randomly from every group mentioned above for an Evans blue assay 5 days after model establishment. For the histomorphology analysis, the expressions of ZO-1 protein and mRNA were studied by hematoxylin-eosin (H&E) staining, transmission electron microscope, Western blot, and Q-PCR using blood and tongue tissues, which were collected from 8 rats randomly chosen from each group.

RESULTSThe papillae density of the rat tongue surface and the caryocinesis frequency of the basal layer were significantly increased in the SAP-TGF group compared with the SO group (P<0.05). Evans blue levels in the tongue tissue of the SAP-TGF group were significantly higher than that of the SO and SAP-NF groups (P<0.05). Vascular ECs were wider and obviously fissured in the SAP-TGF group under transmission electron microscope observation. The protein and mRNA expression of ZO-1 in the SAP-TGF group were lower than those in the SAP-NF (P<0.05).

CONCLUSIONSReproductive activity enhancement of glossal epithelial cells was one of the main characteristics of thick greasy tongue fur formation. An increase in vasopermeability was closely associated with thick greasy tongue fur formation. Tight junction structural variation of vascular ECs might play an important role in the pathological and physiological process of thick greasy tongue fur formation.

Animals ; Blotting, Western ; Cell Membrane Permeability ; Endothelial Cells ; cytology ; Evans Blue ; metabolism ; Gene Expression Regulation ; Male ; Membrane Proteins ; genetics ; metabolism ; Phosphoproteins ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Tongue ; pathology ; ultrastructure ; Zonula Occludens-1 Protein

OBJECTIVETo explore mechanism of dermal toxicity of trichloroethylene(TCE).

METHODSNormal human keratinocytes (KC) were isolated from foreskins of healthy donors undergoing circumcision by two-step trypsin digestion and cultured in serum-free medium. Cells were treated with medium, 1% acetone (volume fraction) 0.125, 0.500 or 2.000 mmol/L TCE for different time (4, 8, 12 or 24) hours. After treatment, MTT assay and ATPase activity detected, inhibition ratio of mitochondrial enzyme was calculated according to optical density (A) value of MTT assay. Mitochondrial membrane potential (MMP) was detected by flow cytometry FCM after being stained with Rhodamine123 (Rh123). Morphological changes were also observed through transmission electron microscope (TEM).

RESULTSCellular viability and ATPase activity declined with dose of TCE, while inhibition ratio of mitochondrial enzyme increased with dose of TCE. FCM results showed that after treatment with 2.000 mmol/L TCE, fluorescence density of Rh123 decreased quickly from 18.73 +/- 0.45(0 h) to 8.20 +/- 0.66(8 h) (P < 0.01). After 8 h, fluorescence density maintained at the level equal to that of 8 h (fluorescence density of Rh123 were 8.20 +/- 0.36 and 8.20 +/- 0.40 for 12 and 24 h respectively, compared with that for 8 h group, P > 0.05). The results also showed that MMP diminished with dose of TCE. Under TEM, mitochondria in TCE-treated group appeared extensive swelling and vacuolar degeneration with less matrix and obscure or vanished mitochondria cristae but in control group, mitochondrial structure was integrated, with uniform matrix and visible mitochondria cristae.

CONCLUSIONSTCE could inhibit mitochondrial metabolic enzyme, reduce ATP production, diminish MMP, and destroy ultrastructure of mitochondria in KC, all these contributing to the cytotoxicity of TCE.

Cell Survival ; drug effects ; Cells, Cultured ; Dose-Response Relationship, Drug ; Humans ; Keratinocytes ; drug effects ; metabolism ; ultrastructure ; Male ; Membrane Potential, Mitochondrial ; drug effects ; Microscopy, Electron, Transmission ; Mitochondria ; drug effects ; metabolism ; ultrastructure ; Trichloroethylene ; toxicity

Escherichia coli (E. coli) has ability to express thin aggregative fimbriae, known as curli, on the cell surface. Previously, a few example of curli expression in serogroup O157:H7 of enterohemorrhagic E. coli (EHEC) were reported, compared to other E. coli groups. However, significance of curliation in the EHEC pathobiology has not been described well in the literature. A highly curliated O157:H7 strain was used in this study in order to elucidate role of curliation in EHEC adherence to cultured HEp-2 cells. The expression of curli in the EHEC isolate was consistent with strong positive indication of Congo-red (CR) binding and formation of clumps in the bottom of the tube containing Luria-Bertani (LB) broth when cultured overnight at 37 degress C. A few CR-binding negative (CR-) colonies occurred spontaneously within the population of CR+ isolate. The CR+ EHEC showed massive aggregative adhesion pattern, whereas the spontaneous CR- strain showed typical localized adherence on HEp-2 cells. Electron microscopy confirmed highly curliated bacteria in the CR+ EHEC sample. Interestingly, the curliation disappeared in a msbB1 and msbB2 double mutant derived from the CR+ EHEC. These results suggest that the compromised outer membrane integrity caused by msbB mutations may abrogate curli production in the CR+ EHEC harbouring penta-acylated lipid A structure in their outer membrane.
Bacterial Adhesion/*physiology ; Bacterial Outer Membrane Proteins/*physiology ; Cell Aggregation ; Cells, Cultured ; Epithelial Cells/*microbiology ; Escherichia coli O157/pathogenicity/*physiology/ultrastructure ; Fimbriae, Bacterial/*metabolism/ultrastructure ; Humans ; Larynx/cytology/microbiology ; Microscopy, Electron

OBJECTIVETo deliver the naked genes into cells through the bioeffects of cell membrane porous produced by low-frequency ultrasound (US) and to investigate the safety by determining the threshold of cell damage and membrane permeability.

METHODSThe suspension of red cells from chickens, rabbits, rats, and S180 cells was exposed to calibrated US field with different parameters in still and flowing state. Laser scanning confocal microscopy, fluorescent microscopy, scanning electron microscopy, flow cytometry and spectrophotometry were used to examine cell morphology, membrane permeability, enzymes, free radicals, naked gene expression efficiency, threshold of cell damage and cell viability.

RESULTSThe plasmid of green fluorescent protein (GFP) as a reporter gene was delivered into S180 cells under optimal conditions without cell damage and cytotoxicity. The transfection rate was (35.83 +/- 2.53)% (n = 6) in viable cells, and the cell viability was (90.17 +/- 1.47)% (n = 6). Also, malondialdehyde, hydroxyl free radical, alkaline phosphatase, and acid phosphatase showed a S-shaped growth model (r = 0.98 +/- 0.01) in response to the permeability change and alteration of cell morphology. The constant E of energy accumulation in US delivery at 90% cell viability was an optimal control factor, and at 80% cell viability was the damage threshold.

CONCLUSIONUS under optimal conditions is a versatile gene therapy tool. The intensity of GFP expression in US group has a higher fluorescent peak than that in AVV-GFP group and control group (P < 0.001). The optimal gene uptakes, expression of gene and safety depend on E, which can be applied to control gene delivery efficiency in combination with other parameters. The results are helpful for development of a novel clinical naked gene therapeutic system and non-hyperthermia cancer therapeutic system.

Animals ; Cell Membrane ; chemistry ; metabolism ; ultrastructure ; Cell Survival ; genetics ; Cells, Cultured ; Chickens ; DNA Damage ; genetics ; Free Radicals ; metabolism ; Genes, Reporter ; genetics ; Green Fluorescent Proteins ; genetics ; Malondialdehyde ; metabolism ; Permeability ; Plasmids ; genetics ; Porosity ; Rabbits ; Rats ; Risk Assessment ; Transfection ; methods ; Ultrasonics