Objective To explore the proper dosage of establishment of stable hepatic oval cells （HOC） prolif-eration model by using 2-acetaminofluorene （2-AAF） combined with two-third partial hepatectomy （2/3 PH） surgery， and to explore isolated and cultured method of HOC in vitro. Methods The 174 Wistar rats were randomly divided into 4 experimental groups （each group enrolled 30 rats）， saline group （n=30）， and untreated group （n=24）. Rats of 4 experi-mental groups were underwent gavage of 5， 10， 15， and 20 mg/（kg ? d） 2-AAF， corresponding to the groups from No.1 to No.4 group. Rats of saline group received saline gavage and rats of untreated group didn’t received any treatment. A standard 2/3 PH surgery was performed on the 5th day after gavage， then the same gavage method was still administrated as preoperation untill rats were sacrificed. The liver tissues of 6 selected rats were adopted and identified by HE staining and immunohistochemical staining on 4， 8， 12， and 16 days after PH for observation of the proliferation of HOC in every group， on 4 days， levels of alanine aminotransferase （ALT） and aspartate aminotransferase （AST） were tested in addition. HOC were isolated and purified by collagenase perfusion method and percoll gradient centrifugation. Results The surv-ival rates of untreated group，saline group，No.1 group，No.2 group，No.3 group，and No.4 group were 100% （24/24），93% （28/30），93% （28/30），90% （27/30），90% （27/30），and 80% （24/30） respectively. Compared with the saline group and untreated group， the levels of serum ALT and AST increased significantly in No.2， No.3， and No.4 group on the 4th day after PH （P＜0.05）. The results of HE staining showed that No.2， No.3， and No.4 group were observed visibly different level of damage at liver tissue， and the proliferation level of HOC were most obviously in No.3 and No.4 group. The results of immunohistochemical staining revealed that proliferation cells were positively expressed oval cell marker-6 （OV-6）. The number of OV-6 positive cells were increased significantly with the increase of dosage of 2-AAF between 4 days and 12 days after operation， and proliferation levels were related with dosages of 2-AAF （P＜0.05）. In all cultured cells， 80% of cells were OV-6 positive cells after isolation and culture by using collagenase perfusion method and percoll gradient centrifugation. Conclusions The methods of gavage of 2-AAF at 15 mg/（kg ? d） combined with 2/3 PH surgery can establish the HOC proliferation model on the 12th day， as well as the rats have lower mortality and better tolerance， especially. The collagenase perfusion method and percoll gradient centrifugation can be used to isolate HOC effectively.
OBJECTIVE: To investigate the effects of dexamethasone on the proliferation and differentiation of bone marrow stromal cells(MSC). METHODS: MSC were isolated and cultured in vitro. After treatment with different concentrations of dexamethasone (0, 10-10, 10-9, 10-8, 10-7 and 10-6 mol/L), the proliferation and alkaline phosphatase (ALP) activity of MSC were measured to evaluate the effect of dexamethasone on the biological characteristics of MSC. RESULTS: Dexamethasone inhibited cell proliferation. With the increase of concentration of dexamethasone, the effect was enhanced, which was more significant when the concentration of dexamethasone was over 10-8 mol/L. At the same time, dexamethasone promoted the activity of ALP. This effect was enhanced with the increase of concentration of dexamethasone, but the alteration was small when the concentration of dexamethasone was over 10-8 mol/L. The effects increased with the time. The activity of ALP was enhanced 2 to 4 times with the dexamethasone for 6 days. CONCLUSION: Dexamethasone inhabit the proliferation of MSC, while induce them to differentiate into osteoblasts. The appropriate concentration of dexamethasone was 10-8 mol/L.
【Abstract】Objective To explore the clinical significance of β-catenin expression in pancreatic carcinoma.Methods The immunohistochemical staining was performed to detect the expression of β-catenin in the specimens of 46 patients with pancreatic carcinoma and the results were statistically analyzed.Results The abnormal expression rate on the membrane was 54.3%, the poorer the differentiation, the higher the abnormal expression rate. The levels of the cases in whom metastasis occurred were much higher than those without metastasis. The abnormal cytoplasm expression rate was 21.7%,which had not significant correlation with the clinical indexes, such as staging, tumor size, grading and metastasis. In 23 patients who accepted intervention chemotherapy before operation, the cytoplasm expression rate in those with tumor mass smaller was 0, which was evidently lower than that of those without tumor mass change (33.3%). Moreover, the abnormal membrane and cytoplasm expression rates had remarkable concordance (63.0%).Conclusion The abnormal membrane expression of β-catenin may accelerate metastasis, and the abnormal expression of β-catenin in cytoplasm may result in cell proliferation.
To investigate the effect of hepatocyte growth factor (HGF) on prol iferation of cultured human eccrine sweat gland epithel ial cells (hESGc) and the involvement of phosphorylation of ERK1/2. Methods hESGc were cultured in keratinocyte serum free medium (KSFM) and the first generation of hESGc was harvested. The expression of C-met was detected by immunocytochemistry. MTT assay was used to detect the effect of HGF on the prol iferation of hESGc. The cells were divided into blank group, control group and experimental group. The culture density was 2 × 103 cells/hole in control group and experimental group. Two hundred μL KSFM with HGF in different levels was added to every hole. hESGcwere cultured in KSFM with HGF at different levels (2, 20, 40 and 80 ng/mL) in experimental group, in KSFM without HGF incontrol group, and in KSFM without HGF and no hESGc in blank group. The cell prol iferation was observed in xperimental group 2 and 4 days later. Western blot was used to detect the expression of phosphorylated ERK1/2 at 40 ng/mL HGF after 0, 5, 30, 90 and 120 minutes. Results The results were positive for anti-C-met staining in the cytoplasm. HGF (40 ng/mL and 80 ng/mL) significantly improved the prol iferation of hESGc (P lt; 0.05). When cultured in the KSFM with 40 ng/mL HGF, the cell prol iferation rate and the absorbance were 74.2%, 0.239 3 ± 0.070 9 at 2 days and 74.8%, 0.287 8 ± 0.074 3 at 4 days; showing significant differences when compared with control group (P lt; 0.05). When cultured in KSFM with 80 ng/mL HGF, the cell prol iferation rate and the absorbance were 54.5%, 0.212 3 ± 0.059 2 at 2 days and 40.3%, 0.231 0 ± 0.056 7 at 4 days; showing significant differences when compared with control group (P lt; 0.05). The expression of p-ERK1/2 reached to the maximum after stimulation of 40 ng/mL HGF for 5 minutes, and relative integral absorbance (RIA) was 0.593 2 ± 0.192 2, increased 8.1 times compared with instant stimulation (P lt; 0.01). Conclusion HGF could induce the prol iferation of hESGc and activate the phosphorylation of ERK1/2 protein.
ObjectiveTo observe apoptosis and proliferation of choledochus wall epithelial cell and fibrocyte, to understand the effects of apoptosis and proliferation on choledochal cyst development.MethodsThirty two cases of cystic dilatation,35 cases of cylindrical dilatation，and 25 cases of cholangiectasis caused by choledocholith were collected. All specimens were offered by department of hepatobiliarypediatric surgery. The apoptosis related index (bcl2 and bax) and cell proliferation index (PCNA) were detected by the immunohistochemical technique; Apoptosis was detected by TUNEL method. ResultsThere was serious mucosal epithelial cell damage in cystic dilatation group. In cylindrical dilatation group there was a damage similar to that of the cystis dilatation group, but the damage was not serious. In control group there was little damage in the duct wall, but there was a low positive rate of apoptosis of 〔epithelium cell (2.74±1.00)% and fibroblast (2.95±0.87）%〕, and a low bcl2 and bax’s expression rate, and a high PCNA’s expression rate 〔epithelium cell (3.74±1.00)%, fibroblast (3.71±1.77)%〕. There was no obvious difference between cylindrical dilatation group and cystic dilatation group (Pgt;0.05): the PCNA’s expression rate was low 〔(0.99±0.51)% and (0.90±0.38)% respectively〕, the bax expression rate was high in remaining epithelial cell, and the positive rate of bax was apparently higher than that of bcl2 (P＜0.05), the positive rate of the apoptosis cell was high 〔(13.94±4.77)%, (7.51±3.46)%〕; the expression rate PCNA were high 〔(9.91±2.91)%,(9.70±3.18)%〕, and expression rate of bax’s was low in the fibre tissue, the positive rate of bcl2 was markedly higher than that of bax, and the positive rate of the apoptosis cell was low 〔(3.74±2.12)%,(4.46±2.41)%〕. There were no marked difference between the two groups (Pgt;0.05). The expression of bcl2 and bax had marked difference both in cylindrical dilatation group and cystic dilatation group and as compared to control group (P＜0.05). ConclusionApoptosis has certain promoting effect in the course of choledochal cyst formation.
ObjectiveTo study the effects of sea cucumber polysaccharide (SCPS) on the proliferation and apoptosis of hepatocellular carcinoma (HCC) cells, and to explore its effect on JAK2/STAT3/survivin pathway. MethodsThe human HCC cell lines HepG2 were placed into 24-well plates after culturing to the logarithmic phase, then dealed with different concentrations (0, 50, 100, 200 μg/mL) of SCPS. The MTT assay was used to detect the effects of different concentrations of SCPS on cell proliferation at 12 h, 24 h, and 36 h. The effect of SCPS on cell apoptosis was analyzed by flow cytometry. The mRNA and protein expression levels of JAK2, STAT3, and survivin were detected by real-time quantitative PCR (qRT-PCR) and Western blot at 36 h after treatment with SCPS, respectively. Then, the human HepG2 cells treated with different concentrations (0, 50, 100, 200 μg/mL) of SCPS were subcutaneously xenografted into nude mice to observe the effect of SCPS on the growth of tumor tissues in nude mice. At the same time, the expressions of phosphorylated JAK2, STAT3, and survivin proteins in tumor tissues were detected by immunohistochemical method. ResultsAfter treatment with different concentrations of SCPS, the proliferation inhibition rate of HepG2 cells increased over time and increased SCPS concentrations (P<0.05). After 36 h cultivation time, the apoptosis rate of cells treated with different concentrations of SCPS was statistically significant (F=117.110, P<0.001) and increased with the increase of SCPS concentrations (P<0.05). The protein expression levels of JAK2, STAT3, survival and their phosphorylated proteins decreased gradually with the increase of SCPS concentrations (P<0.05), but there was no significant difference in the mRNA expression level (P>0.05). With the increase of SCPS concentration, the tumor volume of nude mice gradually reduced (P<0.05). At the same time, the results of immunohistochemical detection showed that the positive expression rates of phosphorylated JAK2, STAT3, and survivin proteins in tumor tissues decreased with the increase of SCPS concentrations (P<0.05). ConclusionFrom preliminary results of this study, SCPS could inhibit the proliferation of HCC cells and promote their apoptosis, which might be achieved by regulating the phosphorylated expressions of JAK2, STAT3, and survivin in the JAK2/STAT3/survivin pathway.
Objective To explore the regulation of peroxisome proliferator-activated receptor γ coactivator 1α( PGC-1α) and NF-E2-related factor 2( Nrf2) on expression of γ-glutamylcysteine synthetase ( γ-GCS) , and their roles in chronic obstructive pulmonary disease( COPD) . Methods Twenty-four SD rats were randomly divided into a COPD group and a normal control group. COPD model was established by intratracheal instillation of lipopolysaccharide ( LPS) and daily exposure to cigarette smog in the COPD group. The lung function was measured and the pathological changes were observed. The protein and mRNA expressions of PGC-1α, Nrf2, and γ-GCS in lung tissue were measured by immunohistochemistry, Western blot, in site hybridization ( ISH) , and reverse transcription-polymerase chain reaction ( RT-PCR ) ,respectively. Results In the COPD group, the pulmonary function ( FEV0. 3, FEV0. 3 /FVC, PEF) damage and lung pathological changes were conformed as morphological characteristics of COPD. The mRNA of PGC-1α and Nrf2 expressed in lung tissues of two group rats in the region consistent with γ-GCS mRNA. The protein and mRNA expressions of PGC-1αand γ-GCS were markedly increased in the COPD group( all P lt;0. 05) ,and the protein expression of Nrf2 was obviously up-regulated ( P lt; 0. 01) , while Nrf2 mRNA had no significant difference between the two groups( P gt;0. 05 ) . Linear correlation analysis showed that the level ofPGC-1αprotein was positively correlated with the levels of Nrf2 protein and mRNA ( r = 0. 775, 0. 515, all P lt; 0. 01) , and the levels of PGC-1αand Nrf2 protein were positively correlated with the levels of γ-GCS protein ( r = 0. 531, 0. 575, all P lt; 0. 01) and mRNA ( r = 0. 616, 0. 634, all P lt; 0. 01) . Conclusions PGC-1α, which may serve as a co-activator of Nrf2, can up-regulate the expression of γ-GCS gene cooperatively with Nrf2 through a common pathway, which might involve in the oxidative and antioxidative mechanism in the pathogenesis of COPD.
ObjectiveTo study the effect of titanium particles on the proliferation, differentiation, and cytomorphology of osteoblasts, and to explore the possible internal relations and mechanism. MethodsCalvarial osteoblasts were separated from 10 newborn Sprague Dawley rats by repeated enzyme digestion, and were cultured in vitro. The cells were identified by alkaline phosphatase (ALP) staining and alizarin red staining. The cells at passage 3 were cultured with titanium particles culture medium at concentrations of 0.01, 0.05, 0.1, 0.5, and 1 mg/mL (0.01, 0.05, 0.1, 0.5, and 1 mg/mL groups). The absorbance (A) values were detected by cell counting kit 8 at 7 days after cultured to compare the effect of titanium particles at different concentrations on proliferation, and median lethal concentration was screened out. The expression of collagen type I was detected by ELISA to observe the effect of titanium particles on differentiation. The osteoblasts co-cultured with titanium particles of median lethal concentration (experimental group) for 7 days, and double fluorescence staining with FITC-phalloidine and propidium iodide was performed. The cytomorphology variation of osteoblasts after swallowing titanium particles was observed under laser scanning confocal microscope. The osteoblasts at passage 3 cultured with culture medium without titanium particles served as control group. ResultsThe cultured cells were identified as osteoblasts by ALP staining and alizarin red staining. Different concentrations of titanium particles could inhibit osteoblasts proliferation and differentiation in varying degrees, showing significant difference when compared with the control group at 7 days after culture (P<0.05). The cell proliferation and differentiation were decreased with increased titanium particles concentration; significant differences were found between the other groups (P<0.05) except 0.01 and 0.05 mg/mL groups (P>0.05). The median lethal concentration of titanium particles was 0.5 mg/mL. Laser scanning confocal microscope showed cellular shrinking, microfilaments distortion, pseudopodia contraction of osteoblasts that swallowed titanium particles in the experimental group. ConclusionTitanium particles can inhibit proliferation and differentiation of osteoblasts. The effect may be related to variation of cytomorphology after swallowing titanium particles.
ObjectiveTo investigate the effect of up-regulation of microRNA-31(miR-31) on the biological behaviour in AGS cell of gastric cancer and on the expression of liver receptor homolog-1(LRH-1), and to analyze the possible mechanisms of miR-31 on initiation and development of gastric cancer. MethodsAGS cells were divided into 3 groups, receiving miR-31 transfection(MT group), empty liposomes transfection(NC group), and treatment of PBS (BC group). Then the cells' proliferation was determined by cell counting kit-8(CCK-8), the apoptosis situation was determined by flow cytometer, the migration was determined by Transwell test, the expression of LRH-1 protein was tested by Western blot method, and the target of miR-31 was tested by luciferase reporter assay. ResultsThe cell's proliferation results showed that the mean of A450 value in MT, NC, and BC groups were 1.31, 2.26, and 2.14 respectively on the 4 days after transfection, which lower in MT group(P<0.01).Results of flow cytometer experiment showed that the mean of apoptosis ratio of MT, NC, and BC groups were 39.5%, 9.3%, and 10.0% respectively, the mean of proportion of cell in G1+S stage were 92.54%, 73.23%, and 74.58% respectively, which both lower in MT group (P<0.05).Results of Transwell experiment showed that the mean of number of migrated cells in MT group was lower (P<0.05).Results of Western blot experiment demonstrated that the expression level of LRH-1 protein in MT group was lower than those of BC group and NC group(P<0.01). ConclusionsUp-regulation of miR-31 can obviously inhibit the proliferation of AGS cell, promoting its apoptosis and depressing its migration ability. On the other side, the up-regulation of miR-31 can also inhibit the expression level of LRH-1 protein, which indirectly induces the inhibition of proliferation of AGS cell. So miR-31 may be an important regulator in the initiation and development of gastric cancer through regulating LRH-1 gene.