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1.
Chinese Journal of Hepatology ; (12): 74-80, 2022.
Article in Chinese | WPRIM | ID: wpr-935911

ABSTRACT

Objective: To investigate whether the selective cyclooxygenase-2 enzyme inhibitors celecoxib has protective effect on the liver of rats with type 2 diabetes mellitus (T2DM) combined with nonalcoholic steatohepatitis (NASH) via inhibiting the expression of Rho/ROCK pathway. Methods: Forty male SD rats were randomly divided into four groups: type 2 diabetes mellitus combined with nonalcoholic steatohepatitis (T2DM-NASH) group, T2DM-NASH + celecoxib group, control group, and control+celecoxib group. The T2DM-NASH and T2DM-NASH + celecoxib groups were fed with high-sugar and fat diet, and the control group and control + celecoxib group were fed with basal diet (25 kJ/kg). Four weeks later, streptozotocin (STZ, 30 mg/kg) was intraperitoneally injected into the NASH group and T2DM-NASH + celecoxib group to induce T2DM model, and the control group and control + celecoxib group were intraperitoneally injected with isovolumic citric acid-sodium citrate buffer. Four weeks after STZ injection, the T2DM-NASH + celecoxib group and the control + celecoxib group were gavaged with celecoxib (10 mg·kg·d) dissolved in normal saline for 4 weeks, and the remaining two groups of rats were gavaged with isovolumic normal saline for 4 weeks. Animals were sacrificed at the end of the 12- weeks, and the liver tissue was collected. Liver pathological changes were observed by HE staining. The expressions of RhoA, RhoA, ROCK1 and ROCK2 proteins in liver were detected by immunohistochemistry and western blot. The expressional condition of RhoA, ROCK1 and ROCK2 mRNA in liver were detected by real-time quantitative PCR. The differences were compared between protein and mRNA expression among the groups by analysis of variance and t-test. Results: Compared with the control group and the control + celecoxib group, the liver tissue of the T2DM-NASH group and the T2DM-NASH + celecoxib group had severe steatosis, and there was partial inflammatory cell infiltration under the light microscope. The expression levels of RhoA, ROCK1 and ROCK2 protein and mRNA were significantly increased (P < 0.05) in each liver tissue, while liver steatosis was reduced to certain extent in T2DM-NASH + celecoxib group than T2DM-NASH group, and the expression levels of RhoA, ROCK1 and ROCK2 protein and mRNA were decreased in each liver tissue of T2DM-NASH group (P < 0.05). Conclusion: The selective cyclooxygenase-2 enzyme inhibitors celecoxib has a protective effect on the liver of rats with T2DM-NASH, and its effect may be achieved by inhibiting the expression of Rho/ROCK pathway.


Subject(s)
Animals , Male , Rats , Cyclooxygenase 2/therapeutic use , Cyclooxygenase 2 Inhibitors/therapeutic use , Diabetes Mellitus, Type 2/drug therapy , Liver , Non-alcoholic Fatty Liver Disease/drug therapy , Rats, Sprague-Dawley
2.
Chinese Journal of Hepatology ; (12): 38-44, 2022.
Article in Chinese | WPRIM | ID: wpr-935906

ABSTRACT

Objective: To investigate the effect of adenovirus-mediated shRNA down-regulating phosphatase and tensin homolog deleted on chromosome 10 (PTEN) expression on vinculin, filamin A, and cortactin in activated hepatic stellate cells (HSCs). Methods: Activated rats hepatic stellate cell line (HSC-T6) was cultured in vitro. Recombinant adenovirus Ad-shRNA/PTEN carrying PTEN targeted RNA interference sequence [short hairpin RNA (shRNA)] and empty control virus Ad-GFP were transfected into HSCs. The PTEN mRNA and protein expression of HSCs in each group were detected by real-time fluorescence quantitative PCR and Western blot. The expressional change of vinculin, filamin A and cortactin in HSCs of each group were detected by confocal laser scanning immunofluorescence microscope. Image-pro plus 6.0 software was used for image analysis and processing. The integrated optical density (IOD) of the fluorescence protein expression was measured. The experiment was divided into three groups: control group (DMEM instead of adenovirus solution in the adenovirus transfection step), Ad-GFP group (transfected with empty virus Ad-GFP only expressing green fluorescent protein), and Ad-shRNA/PTEN group (recombinant adenovirus Ad-shRNA/PTEN carrying shRNA targeting PTEN and expressing green fluorescent protein). One-way analysis of variance was used for comparison of mean value among the three groups, and LSD-test was used for comparison between the groups. Results: shRNA targeted PTEN was successfully transfected and the expression of PTEN mRNA and protein in HSC (P < 0.05) was significantly down-regulated. HSCs vinculin was mainly expressed in the cytoplasm. HSCs vinculin fluorescence IOD in the Ad-shRNA/PTEN group (19 758.83 ± 1 520.60) was higher than control (7 737.16 ± 279.93) and Ad-GFP group (7 725.50 ± 373.03) (P < 0.05), but there was no statistically significant difference between control group and Ad-GFP group (P > 0.05). There was no statistically significant difference in the fluorescence IOD of Filamin A among the three groups (P > 0.05), but the subcellular distribution of Filamin A among the three groups were changed. Filamin A in the Ad-shrNA /PTEN HSC group was mainly distributed in the cytoplasm. Filamin A HSC was mainly located in the nucleus.The filamin A HSC in the control group and Ad-GFP group was mainly located in the nucleus. The nucleocytoplasmic ratio of Filamin A in the AD-shrNA /PTEN group (0.60 ± 0.15) was significantly lower than control group (1.20 ± 0.15) and Ad-GFP group (1.08 ± 0.23), P < 0.05. but there was no statistically significant difference in filamin A nucleocytoplasmic ratio of HSC between the control group and the Ad-GFP group (P > 0.05). Cortactin HSCs in the three groups was mainly distributed in the cytoplasm. The cortactin fluorescence IOD of HSCs in the Ad-shRNA/PTEN group was significantly higher than control group (22 959.94 ± 1 710.42) and the Ad-GFP group (22 547.11 ± 1 588.72 ) (P < 0.05), while there was no statistically significant difference in the IOD of cortactin fluorescence in HSCs between the control group and the Ad-GFP group (P > 0.05). Conclusion: The down-regulation of PTEN expression raises the expression of microfilament-binding protein vinculin and cortactin, and changes the subcellular distribution of another microfilament binding protein filamin A, that is, translocation from nucleus to the cytoplasm in activated HSC in vitro.


Subject(s)
Animals , Rats , Adenoviridae/metabolism , Carrier Proteins , Cell Proliferation , Cortactin , Filamins/genetics , Hepatic Stellate Cells/metabolism , PTEN Phosphohydrolase/metabolism , RNA, Small Interfering/genetics , Vinculin/genetics
3.
Chinese Journal of Endocrinology and Metabolism ; (12): 598-601, 2018.
Article in Chinese | WPRIM | ID: wpr-806788

ABSTRACT

The rotary cell culture system(RCCS)was used to simulate the microgravity environment, and FRTL-5 cells were divided into simulated microgravity group(SMG)and normal gravity group(NG). FRTL-5 cells were harvested after treatment for 6, 12, 24, and 36 h, the cell viability was measured by MTT assay, and the cells cycles were detected by flow cytometry. The ultrastructure of FRTL-5 cells was observed under laser confocal microscope with FITC-labeled technique. The MTT assay showed that the proliferation of FRTL-5 cells was significantly inhibited after RCCS treatment for 6, 12, 24, and 36h compared with NG(P<0.05), in which the most obvious effect was observed at 24h. The flow cytometry showed that the proportion of FRTL-5 cells at G1 stage in RCCS group was increased significantly after 6, 12, 24, and 36h compared with NG(P<0.05), while the proportion of FRTL-5 cells at S stage was decreased significantly(P<0.05)except that cultured with RCCS for 6 h. The proportion of FRTL-5 cells at G2/M stage was decreased in early phase(6-12 hours)of RCCS culture, with the lowest at 12h and transient increase at 24h of RCCS culture. The laser confocal microscope revealed that there were local microfilament depolymerization, tension fibers decrease, structure disorder, cellular pseudopodia reduction, and irregular shape among FITC-labeled FRTL-5 cells cultured with RCCS for 36h. (Chin J Endocrinol Metab, 2018, 34: 598-601)

4.
Medical Journal of Chinese People's Liberation Army ; (12): 599-602, 2015.
Article in Chinese | WPRIM | ID: wpr-850250

ABSTRACT

The migration and invasion of trophoblast are closely associated with the cytoskeleton. The blocking of cytoskeleton's dynamic restructuring might inhibit the migration of the cell into the spiral artery and decidua, and it would lead to a shallow trophoblast implantation, ischemia and anoxia of placentome, and the occurrence of preeclampsia (PE) eventually. Shallow trophoblast implantation plays a key role in the development of PE, and the depth of implantation was shown to be directly related to the occurrence of PE. So the research in regard to the relationship between cytoskeleton and trophoblast's migration are of great significance for the understanding of the pathogenesis of PE. In recent years a number of studies on the role of cytoskeleton in shallow implantation have been reported from time to time, and their results will be analyzed comprehensively in the present article.

5.
Chinese Journal of Microbiology and Immunology ; (12): 771-775, 2011.
Article in Chinese | WPRIM | ID: wpr-419913

ABSTRACT

Objective To investigate the invasion,internalization and the organelles damage of the cultured dendritic cells ( DC2.4 strain) during Vibrio vulnificus (Vv) infection.Methods The study model was the cultured DCs infected by Vv 1.1758 strain.Electron microscopy was used to observe the localization of bacteria in different time point of infection,cell morphology and the process of organelles changes.The cytoskeleton structure including the microfilaments and the microtubules rearrangement was examined by the fluorescence microscope.Results The Vv were pinocytosed into the DC cells through double-sides,and localized at 1-2 μm of the inner side membrane.It cost 1.27,1.87,3.43 hours reaching the infection ratio of 25%,50%,75%,respectively.Using electron microscopy,the DCs had been observed the phagosome formation within 1h,chromatin activation within 2 h,chromatin aggregation 4 h,and the significant cytoskeleton structure disruption within 6 h.Endoplasmic reticulum,mitochondria and lysosomes became swollen.In DCs,the protruding filaments gradually reduced,and their shape changed from the point-like to the linearlike aggregation at the inner side of the plasma membrane,extended microtubules disappeared,the microtubules at the outside nuclear membrane striking rearranged.Conclusion After DC was infected by Vv,the bacteria were pinocytosed into the inner side of DC membrane,and the microfilaments were observed to move from the cytoplasm to cell membrane.In addition,the microtubules moved from the synapse and the cell membrane to the nuclear membrane.The high lethality of Vv could provoke to the DCs cytoskeleton rearrangements.

6.
Chinese Journal of Digestion ; (12): 604-608, 2011.
Article in Chinese | WPRIM | ID: wpr-419708

ABSTRACT

Objective To investigate the expression of actin-associated protein Transgelin in pancreatic cancer with or without diabetes and its effects on migration and invasion in SW1990 cell line. Methods The expression of Transgelin in 92 pancreatic cancer tissue specimens (45 cases accompanied with diabetes) and adjacent tumor-free tissue specimens (over 5cm from the edge of the tumor) was detected by immunohistochemistry, and their association with clinical pathological characteristics were also analyzed. Transgelin siRNA was designed and transfected into pancreatic cancer cell line SW1990. The changes of migration and invasion before and after transfection were observed through Transwell test.Results The positive percentage of Transgelin expression in pancreatic cancer was 68.5 % (63/92), which was significantly higher than that of adjacent tumor-free tissues[33.7% ( 31/92), P< 0.05]. The positive percentage of Transgelin expression in pancreatic cancer accompanied with diabetes was 84.4% (38/45), which was significantly higher than that without diabetes[53.2% (25/47), P<0.05]. The expression of Transgelin in pancreatic cancer tissues was associated with lymph nodes metastasis and TNM staging (both P<0.05), but not related with gender, age, site, differentiation and portal vein or nerve invasion (P>0.05). After Transgelin was interfered for 48 hours, the migration ability was significantly lower (migration cell number 49.2 ±9.5 cells) than negative control group (61.9±7.5 cells) and blank group (65.3±10.6 cells) (both P<0.05), and the invasion of SW 1990 cells (48.0 ± 8.6 cells) also significantly lower than negative control group (63.5±11.4 cells) and blank group (67.5±9.6 cells) (both P<0. 05). Conclusion Transgelin may involve in the metastasis of pancreatic cancer accompanied with diabetes through promoting pancreatic cancer cell migration and invasion.

7.
Journal of Shanghai Jiaotong University(Medical Science) ; (12): 1143-1147, 2009.
Article in Chinese | WPRIM | ID: wpr-405555

ABSTRACT

Objective To investigate the mechanisms of phagocytosis of virulent Leptospira by peritoneal macrophages of guinea pigs,andevaluatetheroleof innateimmuneinthepathogenesisof leptospirosis. Methods Peritoneal macrophages of guinea pigs were extracted. Three specific inhibitors ( microfilament inhibitor cytochalasin D,microtube inhibitor colchicine and PI3K signalling pathway inhibitor LY294002) were added respectively to the macrophages 1 h before the infection of virulent Leptospira interrogans serovar Lai type strain Lai in vitro.Meanwhile, control group without inhibitor was established.Phagocytosis was observed by laser scanning confocal microscopy and phagocytic rates were evaluated by flow cytometry 3 h after infection.ResultsThe phagocytic rates of control group, cytochalasin D group, colchicine group and LY294002 group were (38.98 ± 0.91)%,(23. 99 ± 1. 40) % ,(40.81±0.91)% and (39.64 ±3.56) %, respectively.The phagocytic rate of cytochalasin D group was significantly lower than that of control group (P < 0. 05), while those of colchicine group and LY294002 group were not significantly different from that of control group (P >0.05). ConclusionMicrofilaments play an important role in the phagocytosis of strain Lai by peritoneal macrophages,but the process is independent on PI3K signalling pathway,and microtubes play little part during the phagocytosis.

8.
Experimental & Molecular Medicine ; : 656-664, 2009.
Article in English | WPRIM | ID: wpr-10780

ABSTRACT

Curcumin is a well known natural polyphenol product isolated from the rhizome of the plant Curcuma longa, anti-inflammatory agent for arthritis by inhibiting synthesis of inflammatory prostaglandins. However, the mechanisms by which curcumin regulates the functions of chondroprogenitor, such as proliferation, precartilage condensation, cytoskeletal organization or overall chondrogenic behavior, are largely unknown. In the present report, we investigated the effects and signaling mechanism of curcumin on the regulation of chondrogenesis. Treating chick limb bud mesenchymal cells with curcumin suppressed chondrogenesis by stimulating apoptotic cell death. It also inhibited reorganization of the actin cytoskeleton into a cortical pattern concomitant with rounding of chondrogenic competent cells and down-regulation of integrin beta1 and focal adhesion kinase (FAK) phosphorylation. Curcumin suppressed the phosphorylation of Akt leading to Akt inactivation. Activation of Akt by introducing a myristoylated, constitutively active form of Akt reversed the inhibitory actions of curcumin during chondrogenesis. In summary, for the first time, we describe biological properties of curcumin during chondrogenic differentiation of chick limb bud mesenchymal cells. Curcumin suppressed chondrogenesis by stimulating apoptotic cell death and down-regulating integrin-mediated reorganization of actin cytoskeleton via modulation of Akt signaling.


Subject(s)
Animals , Chick Embryo , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Apoptosis/drug effects , Cells, Cultured , Chondrogenesis/drug effects , Curcumin/pharmacology , Cytoskeleton/drug effects , Limb Buds/cytology , Mesenchymal Stem Cells/cytology , Proto-Oncogene Proteins c-akt/metabolism
9.
Tumor ; (12): 659-662, 2009.
Article in Chinese | WPRIM | ID: wpr-434191

ABSTRACT

Objective:To study the relationship between the expression of filamin A (FLNa) and clinical pathological features in invasive breast carcinoma. Methods:The expression of FLNa was measured by immunohistochemistry and flow cytometry in 46 cases of invasive breast carcinoma. Results:The expression level of FLNa was increased in poorly differentiated invasive breast carcinoma. There were significant differences between well-moderately differentiated and poorly differentiated groups (P<0.05). The expression level of FLNa in invasive breast carcinoma with lymph node metastasis was higher than that in non-metastasis group (P<0.05). Conclusion:The level of FLNa expression correlated with invasion and metastasis of invasive breast carcinoma. FLNa can be used as an assistant marker for prediction of breast carcinoma prognosis and has the potential to be a new target for cilinical therapy.

10.
Chinese Journal of Neurology ; (12): 758-761, 2009.
Article in Chinese | WPRIM | ID: wpr-392078

ABSTRACT

Objective To report filaminopathy with novel insertion mutation in a Chinese family.Methods Total 19 patients from successive 5 generations involved in an autosomal dominant family. The detailed clinical manifestations had been described (Chinese Journal of Neurology, 2008, 41:751-755).The filamin C gene sequencing was performed in 3 patients, 5 family members without symptoms and 50 normal persons. The amplified fragments of the exon 18 in filamin C gene were cloned into pBluesripts vectors, then sequenced and identified with capillary electrophoresis. Results 18-nucleotide deletion and 6-nucleotide insertion were identified in the exon 18 of filamin C gene. The mutation caused the disturbance of the seventh immunoglobulin-like domain in filamin C, leading to the instability of dimmers of filamin C.Another 2 patients in the family had same mutation while 5 family members without symptoms and 50 normal controls were normal. Conclusion The novel nucleotide deletion-insertion in exon 18 of filamin C gene causes filaminopathy. This disease can appear in non-Nordic race.

11.
Journal of Third Military Medical University ; (24)2003.
Article in Chinese | WPRIM | ID: wpr-567564

ABSTRACT

Objective To study the effect of neurotrophic tyrosine kinase receptor B(TrKB) on in vitro invasiveness of malignant transformed hFOB1.19 cells and the role of TrKB in invasion and metastasis of osteosarcoma.Methods Expression of TrKB in malignant transformed hFOB1.19 cells and SaOS-2 osteosarcoma cells was detected by RT-PCR and immunofluorescence.Function of TrKB of malignant transformed hFOB1.19 cells was further studied.Malignant transformed hFOB1.19 cells were treated with specific tyrosine kinase inhibitor K252a for 24 h as a treatment group,and untreated malignant transformed hFOB1.19 cells into which DMSO was added served as a control group.Morphology of cells was observed under an inverted phase contrast microscope.Cell invasiveness was detected by Transwell assays.Microfilaments of cells were detected by actin immunofluorescence.Results The expression of TrKB was significantly higher in malignant transformed hFOB1.19 cells than in SaOS-2 osteosarcoma cells(P

12.
Korean Journal of Fertility and Sterility ; : 229-236, 2002.
Article in Korean | WPRIM | ID: wpr-131958

ABSTRACT

OBJECTIVE: The purpose of this study was to evaluate the effect of Cytochalasin B (CCB) on the cytoskeletal stability of mouse oocyte frozen by vitrification. METHODS: Mouse oocytes retrieved from cycle stimulated by PMSG and hCG were treated by CCB and then vitrified in EFS-30. These oocytes were placed onto an EM grid and submerged immediately in liquid nitrogen. Thawing of the oocytes was carried out at room temperature for 5 seconds, then the EM grid was placed into 0.75 M, 0.5 M and 0.25 M sucrose at 37degress C for 3 minutes, each. These oocytes were fixed in 4% formaldehyde for an hour and then washed in PPB for 15 minutes 3 times, then incubated in PPB containing anti-tubulin monoclonal antibody at 4degress C overnight. And then, the oocytes were incubated with FITC-conjugated anti-mouse IgG and propidium iodide (PI) for 45 minutes. Pattern of microtubules and microfilaments of oocytes were evaluated with a confocal microscope. RESULTS: The rate of oocytes containing normal microtubules and microfilaments was significantly decreased after vitrification. The rate of oocyte containing normal microtubules in CCB treated group was higher than those in non-treated group (53.7% vs. 48.9%), but the difference was not significant. The rate of oocyte containing normal microfilaments in CCB treated group was significantly higher than those in non-treated group (64.5% vs. 38.3%, p<0.05).CONCLUSION: Microfilaments stability could be improved by CCB treatment prior to vitrification. It is suggested that CCB treatment prior to vitrification improve stability of cytoskeleton and then increase success rate in IVF-ET program using vitrification and thawing oocyte.


Subject(s)
Animals , Mice , Actin Cytoskeleton , Cytochalasin B , Cytoskeleton , Formaldehyde , Immunoglobulin G , Microtubules , Nitrogen , Oocytes , Propidium , Sucrose , Vitrification
13.
Korean Journal of Fertility and Sterility ; : 229-236, 2002.
Article in Korean | WPRIM | ID: wpr-131955

ABSTRACT

OBJECTIVE: The purpose of this study was to evaluate the effect of Cytochalasin B (CCB) on the cytoskeletal stability of mouse oocyte frozen by vitrification. METHODS: Mouse oocytes retrieved from cycle stimulated by PMSG and hCG were treated by CCB and then vitrified in EFS-30. These oocytes were placed onto an EM grid and submerged immediately in liquid nitrogen. Thawing of the oocytes was carried out at room temperature for 5 seconds, then the EM grid was placed into 0.75 M, 0.5 M and 0.25 M sucrose at 37degress C for 3 minutes, each. These oocytes were fixed in 4% formaldehyde for an hour and then washed in PPB for 15 minutes 3 times, then incubated in PPB containing anti-tubulin monoclonal antibody at 4degress C overnight. And then, the oocytes were incubated with FITC-conjugated anti-mouse IgG and propidium iodide (PI) for 45 minutes. Pattern of microtubules and microfilaments of oocytes were evaluated with a confocal microscope. RESULTS: The rate of oocytes containing normal microtubules and microfilaments was significantly decreased after vitrification. The rate of oocyte containing normal microtubules in CCB treated group was higher than those in non-treated group (53.7% vs. 48.9%), but the difference was not significant. The rate of oocyte containing normal microfilaments in CCB treated group was significantly higher than those in non-treated group (64.5% vs. 38.3%, p<0.05).CONCLUSION: Microfilaments stability could be improved by CCB treatment prior to vitrification. It is suggested that CCB treatment prior to vitrification improve stability of cytoskeleton and then increase success rate in IVF-ET program using vitrification and thawing oocyte.


Subject(s)
Animals , Mice , Actin Cytoskeleton , Cytochalasin B , Cytoskeleton , Formaldehyde , Immunoglobulin G , Microtubules , Nitrogen , Oocytes , Propidium , Sucrose , Vitrification
14.
Korean Journal of Anatomy ; : 665-676, 2000.
Article in Korean | WPRIM | ID: wpr-656870

ABSTRACT

The microfilaments of hepatocyte are distributed throughout the vicinity of cell membranes, especially numerous around the region of bile canaliculus, and provide the maintenance of cell shape, cellular wall tension, canalicular motility, the secretion for bile, etc. To evaluate the relationship between the microfilament and alteration of cell shape, we examined the morphological changes of cultured rat hepatocytes, following treatments with phalloidin or cytochalasin D with fluorescent and electron microscopes. 1. In the fluorescent micrographs, actin microfilament was distributed near the plasma membrane and bile canaliculus. 2. Both drugs, phalloidin or cytochalasin D, produce the cytoplasmic protrusions from the surface. Their shapes were pedunculated with narrow neck or bulged with broad base, respectively. 3. In the phalloidin treated group, cytoplasmic protrusion was seperated from the internal cytoplasm by microfila-ments networks at the narrow base. In contrast, in the cytochalasin D treated group, cytoplasm was bulged with broad base and kept in direct continuity with the canalicular ectoplasm. 4. Pericanalicular ectoplasm of phalloidin treated group was widened and accumulated with microfilaments. But, bile canaliculus of cytochalasin D treated group was markedly dilated and devoid of microvilli, and the ectoplasm was almost disappeared. Considering above results, dysfunction of microfilaments leads to the structural changes and inhibition of bile secretion of hepatocytes.


Subject(s)
Animals , Rats , Actin Cytoskeleton , Bile , Bile Canaliculi , Cell Membrane , Cell Shape , Cytochalasin D , Cytoplasm , Hepatocytes , Microvilli , Neck , Phalloidine
15.
Korean Journal of Anatomy ; : 661-671, 1999.
Article in Korean | WPRIM | ID: wpr-654656

ABSTRACT

To examine the role of actin microfilaments which are located at beneath the plasma membrane, we observed the ultrastructural changes of rat hepatocyte induced by alteration of the microfilamentous integrity. The isolated hepatocytes from Sprague-Dawley were cultured in the L-15 medium containing phalloidin (agent that cause polymerization of actin) or cytochalasin D (agent that cause depolymerization of actin) for 30 min, 1 hour, 2 hours, 4 hours, 10 hours and 20 hours, respectively. The results observed with scanning and transmission electron microscope were as follows. 1. Following the alteration of actin microfilaments, bile canaliculi were dilated and devoid of microvilli. In phalloidin treated group, the thickening of microfilamentous ectoplasm was more marked than that of cytochalasin D treated group. Whereas, the dilation of bile canaliculi was more marked in cytochalasin D group. 2. Both drugs, phalloidin or cytochalasin D, produced the alteration of cell shape to form cytoplasmic protrusions at the cell surface. In the phalloidin treated group, protrusions were pedunculated, and the microfilament networks were accumulated at the narrow neck region. 3. In cytochalasin D treated group, no microfilament barrier was seen at the broad base of protrusion which exhibit direct continuity with the internal cytoplasm. 4. Single hepatocyte tend to recover their structural integrity as those in vivo. The new bile canaliculus was sealed off at the intercellular space by tight junctions, and intercellular contacts were established by the junctional complexes. The results demonstrated that excessive accumulation or depletion of microfilaments induced by phalloidin or cytochalasin D altered the cell shape different, respectively. The microfilaments of ectoplasm play an important role in the maintenance of the structural integrity of cultured hepatocytes.


Subject(s)
Animals , Rats , Actin Cytoskeleton , Bile Canaliculi , Cell Membrane , Cell Shape , Cytochalasin D , Cytoplasm , Extracellular Space , Hepatocytes , Microvilli , Neck , Phalloidine , Polymerization , Polymers , Rats, Sprague-Dawley , Tight Junctions
16.
Korean Journal of Pathology ; : 51-57, 1998.
Article in Korean | WPRIM | ID: wpr-58392

ABSTRACT

The cells of glomerular mesangium is composed mostly of intrinsic contractile mesangial cells and a few macrophages. Injury to the mesangium is central to many glomerular diseases. This study was aimed to evaluate and compare the expressions of alpha-smooth muscle actin (ASMA) and lysozyme in the mesangium of various human glomerular diseases and also of according to the severity of their progressions. We performed immunohistochemical and transmission electromicroscopic examinations in 51 cases of renal biopsy including 5 normal kidneys. The results were as follows; (1) ASMA staining was negligible in normal glomeruli. (2) Increased ASMA staining was observed in the mesangium of glomeruli from all specimens of primary glomerular disease, regardless of their diagnosis. (3) The staining intensity of ASMA in mesangium was mild in minimal change disease and membranous glomerulonephritis, and strong in focal segmental glomerulosclerosis (FSGS), diffuse mesangial hypercellularity, membranoproliferative glomerulonephritis (MPGN), and IgA nephropathy (IgAN). (4) The staining intensity of ASMA have no correlation with mesangial immune deposits. (5) The staining intensity of ASMA in mesangium was inversely correlated with the disease progression in FSGS and IgAN. (6) Glomeruli showing global or segmental sclerosis invariably lacked ASMA. (7) Compared with ASMA, the mesangial cells with lysozyme expression were very rare, even though it was in proportion to ASMA staining. Interstitial ASMA expression was confined to fibrotic area in various glomerular diseases. In conclusion, the expression of ASMA and lysozyme in mesangium are increased in a variety of glomerular diseases, regardless of disease entity. Their intensity was in proportion to the mesangial cell proliferation. In progressive glomerulonephritis, such as IgAN and FSGS, the increased expression of ASMA was prominent in the early lesion, and decreased with the progression of the glomerular sclerosis.


Subject(s)
Humans , Actin Cytoskeleton , Actins , Biopsy , Diagnosis , Disease Progression , Glomerular Mesangium , Glomerulonephritis , Glomerulonephritis, IGA , Glomerulonephritis, Membranoproliferative , Glomerulonephritis, Membranous , Glomerulosclerosis, Focal Segmental , Kidney , Macrophages , Mesangial Cells , Muramidase , Muscle, Smooth , Nephrosis, Lipoid , Sclerosis
17.
Journal of the Korean Ophthalmological Society ; : 1648-1655, 1996.
Article in Korean | WPRIM | ID: wpr-196892

ABSTRACT

Seven fibrovascular diabetic preretinal membranes were examined with lightmicroscophic immunohistochemical stain and electron-microscopy to evaluate the possibility of pericytes to be involved in membrane contraction. Pericytes were positively stained with anti-actin antibody together with some stromal cells thought to be myofibroblasts presumedly. On transmission electron microscopic study, pericytes were highly active with numerous cytoplasmic processes and contained abundant microfilaments considered as actin in their cytoplasm. Pericyte/endothelial cell ratio of vascular channels were increased in some actively proliferative portion of the membranes. Myofibroblasts that contain abundant cytoplasmic microfilaments were also demonstrated in the extravascular stroma of the membranes and were very similar to the pericytes morphologically. Although the evidence that the pericytes are related to the origin of the myofibroblasts could not be demonstrated, this study suggested that the pericytes may play important roles in development and contraction mechanism of fibrovascular diabetic preretinal membranes.


Subject(s)
Actin Cytoskeleton , Actins , Cytoplasm , Membranes , Myofibroblasts , Pericytes , Stromal Cells
18.
Journal of Kunming Medical University ; (12)1990.
Article in Chinese | WPRIM | ID: wpr-515878

ABSTRACT

The invasion of malignant cells into smooth muscle cells was shown by EM.We dicsovered that the malignant cells adhered to and penetrated the smooth muscle cells with their microvilli and pseudopodia.The microfilament in the microvilli and pseudopodia is the motion skeleton of cancer cells.Studying the structure and function of the microfilament fur- ther is important for researching the metastasis of tumor.

19.
Journal of Kunming Medical University ; (12)1986.
Article in Chinese | WPRIM | ID: wpr-515962

ABSTRACT

After studying the surface structure of 9 kinds of malignant cells cultured on the three-dimensional substratum by SEM and TEM,it was found that myriad microvilli appeared on the surface of the malignant cells.The number and distribution varied with the cell cycle.The function of the microvilli was related with the nutrition,migration and invasion of the malignant cells.The microfilament is the skeletal structure of microvilli.

20.
Chinese Journal of Immunology ; (12)1985.
Article in Chinese | WPRIM | ID: wpr-535193

ABSTRACT

Our previous experiment demonstrated that CEA is a cell adhesion molecule.The mechanism of cell adhesion activity of CEA was studied in this experiment using CEA positive cells line LoVo.Electron—micrographys study showed that LoVo cells adhered by cross contact of microvilli on the cell surface,and formation of gap junction and desomosomal junction were also observed.Cell adhesion activity of CEA was apperently influenced by emperature,NaN3,EDTA and cytochalasin B,showing that cell adhesion is an energy-consuming process depending on bivalent cation and movement of microfilament.A model of CEA on cell membrane was put forward.

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