OBJECTIVETo investigate the expression of immune-related genes during osteogenesis stimulated by simvastatin.

METHODSAfter treated with simvastatin, the expression of immune-related genes of mouse osteoblast was examined with gene chip (BiostarM-140s).

RESULTSThere were 16 differently expressed genes related to immune function, with nine down-regulated genes and seven up-regulated genes.

CONCLUSIONSAfter treated with simvastatin, expression of inflammation related genes is down-regulated and inflammation inhibitor genes is up-regulated in mouse osteoblasts.

Animals ; Down-Regulation ; Gene Expression Profiling ; Gene Expression Regulation ; Mice ; Osteoblasts ; drug effects ; immunology ; Osteogenesis ; drug effects ; Simvastatin ; pharmacology

OBJECTIVETo investigate the effect of hydroxycamptothecin (HCPT) on the proliferation, cell cycle and apoptosis of human lung carcinoma cell line A549.

METHODSThe growth of A549 cells exposed to HCPT was observed by staining with acridine orange/ethidium bromide dye. Agarose gel electrophoresis was performed to detect DNA fragmentation of the apoptotic cells. The cell cycle distribution of the exposed cells was analyzed using flow cytometry, and cell apoptosis was examined with annexin V-FITC/PI staining. RT-PCR was used to investigate Bcl-2 gene expression changes in the exposed cells.

RESULTSAgarose gel electrophoresis of the DNA from HCPT-treated cells showed a DNA ladder, and typical apoptotic appearance of the exposed cells was observed under fluorescence microscope. Treatment of A549 cells with 1 µmol/L HCPT for 24 h resulted in a cell apoptosis rate of 18.11%, significantly higher than the rate in control cells (0.09%, P<0.05). The treatment also caused a significant reduction of Bcl-2 mRNA expression by 70% (P<0.05).

CONCLUSIONHCPT can significantly inhibit the proliferation, induce apoptosis, and down-regulate Bcl-2 gene expression in human lung carcinoma cell line A549, suggesting the involvement of Bcl-2 gene in the inhibitory effect of HCPT on A549 cells.

Camptothecin ; analogs & derivatives ; pharmacology ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Down-Regulation ; Gene Expression Regulation, Neoplastic ; drug effects ; Genes, bcl-2 ; Humans ; Transfection

This study was purposed to investigate the effect of rapamycin on proliferation, apoptosis, cell cycle progression and the regulation of chemokine receptor CXCR4 on RPMI8226 cells. Different concentrations of rapamycin were used to treat the multiple myeloma cell line RPMI8226 for different times. The proliferation of the cells was detected by MTT assay; the apoptosis rate and cell cycle were determined by flow cytometry (FCM); apoptosis of cells was observed by inverted microscopy; the cylin D1, CXCR4 and mTOR mRNA expressions were detected by RT-PCR or FQ-PCR after treating RPMI8226 cells with different concentrations of rapamycin. The results indicated that the rapamycin could inhibit the proliferation of RPMI8226 cells and induce their apoptosis. The cell cycle was arrested at the G(0)/G(1) phase. PCR results showed the down-regulation of mTOR, cyclin D1 and mTOR mRNA expressions after treating RPMI8226 cells with different concentrations of rapamycin for 24 hours. It is concluded that the rapamycin significantly inhibits the growth of RPMI8226 cells in a dose-and time-dependent mannes and induce cell apoptosis. Cell cycle arrests at the G(0)/G(1) phase, may be due to the down-regulation of the mTOR and cyclin D1 expressions. In additions, the down-regulation of CXCR4 mRNA expression is correlated with the reduction of adhesion between myeloma cells and stromal cells.
Apoptosis ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Down-Regulation ; Humans ; Receptors, CXCR4 ; metabolism ; Sirolimus ; pharmacology

Both tetrandrine (Tet) and 5-bromotetrandrine (BrTet) can effectively reverse P-glycoprotein (P-gp)-mediated multidrug resistance (MDR). The structure of multidrug resistance associated protein 7 (MRP7) has its own specificity and difference compared with other members of the MRP family. This study was aimed to investigate whether Tet and BrTet can inhibit the expression level of MRP7 so as to further look into the mechanisms of the reversal effects of Tet and BrTet on MDR. The inhibitory effects of daunorubicin (DNR) used alone on the proliferation of K562 and K562/A02 cells were evaluated by MTT assay, the IC(50) of DNR and drug resistant folds were calculated. The mRNA level of MRP7 was tested by real-time PCR, and the protein levels of MRP7 and P-gp were tested by Western blot. The DNR accumulation was analyzed by flow cytometry (FCM). The results showed that the resistance of K562/A02 cells to DNR was 23.65-folds of that of K562 cells. After administration of 1 µmol/L Tet or 2 µmol/L BrTet, the mRNA level of MRP7 in the K562/A02 cells decreased to 2% and 12% respectively, and the protein level of MRP7 decreased by 53.2% and 83.7% respectively. The protein level of P-gp decreased by 58.47% and 52.20% in the 1 µmol/L Tet and 2 µmol/L BrTet groups. FCM detection showed that 1 µmol/L Tet and 2 µmol/L BrTet significantly increased the accumulation of DNR in K562/A02 cells by 94.32% and 271% respectively. It is concluded that Tet and BrTet both can reverse MDR in vitro. The mechanisms may be related to the inhibition of MRP7 overexpression and the increase of anticancer drug concentration in cells. At the same molar concentration, the effects of Tet and BrTet in inhibiting the protein level of MRP7 expression do not show significant difference.
Benzylisoquinolines ; pharmacology ; Down-Regulation ; drug effects ; Drug Resistance, Multiple ; drug effects ; Drug Resistance, Neoplasm ; drug effects ; Humans ; K562 Cells ; Multidrug Resistance-Associated Proteins ; metabolism

To explore the effect of chronic high dose of insulin on lipolysis in porcine adipocytes and the underlying molecular regulation mechanisms, we cultured primary porcine adipocytes and incubated them with different concentrations of insulin (0, 200, 400, 800, 1600 nmol/L) for 24-96 h in the absence or presence of specific protein kinase A (PKA) inhibitor or extracellular signal-related kinase (ERK) inhibitor. Then, we measured the glycerol release into the culture media as an indicator of the lipolysis, and observed the lipid accumulation morphology by phase-contrast microscopy. Further, we analyzed the gene expressions of perilipin A and peroxisome proliferator-activated receptor-gamma 2 (PPAR gamma 2) with semi-quantitative RT-PCR and Western blotting, respectively. The results showed that chronic high dose of insulin stimulated lipolysis in differentiated porcine adipocytes in a dose- and time-dependent manner, and significantly attenuated the lipolytic response to isoprenaline. Meanwhile, the protein and mRNA expressions of PPAR gamma 2 and perilipin A were significantly reduced. In addition, both PKA and ERK inhibitors significantly suppressed insulin-stimulated lipolysis, however, only ERK inhibitor reversed the insulin-induced down-regulation of perilipin A. These findings imply that chronic high dose of insulin stimulates lipolysis in porcine adipocytes by repressing perilipin A, which is involved in ERK pathway.
Adipocytes ; cytology ; drug effects ; metabolism ; Animals ; Carrier Proteins ; Dose-Response Relationship, Drug ; Down-Regulation ; drug effects ; Insulin ; pharmacology ; Lipolysis ; drug effects ; Perilipin-1 ; Phosphoproteins ; metabolism ; Swine

Lead exposure is a known potential risk factor for neurodegenerative diseases such as Alzheimer's disease (AD). Exposure to lead during the critical phase of brain development has been linked with mental retardation and hypophrenia in later life. This study was aimed to investigate the effects of lead exposure of pregnant mice on the expressions of insulin-degrading enzyme (IDE) and nerve growth factor (NGF) in the hippocampus of their offspring. Blood samples were collected from the tail vein, and after anesthetizing the pups, the brain was excised on postnatal day 21. Lead concentrations were determined by graphite furnace atomic absorption spectrophotometry, and the expressions of IDE and NGF were determined by immunohistochemistry and Western blotting. Results showed that the reduction in IDE and NGF expression in the hippocampus of pups might be associated with impairment of learning and memory and dementia induced by maternal lead exposure during pregnancy and lactation.
Animals ; Down-Regulation ; Female ; Gene Expression Regulation, Developmental ; drug effects ; Gene Expression Regulation, Enzymologic ; drug effects ; Hippocampus ; drug effects ; growth & development ; metabolism ; Insulysin ; genetics ; metabolism ; Lead ; toxicity ; Mice ; Pregnancy ; Prenatal Exposure Delayed Effects ; chemically induced

OBJECTIVETo investigate the role of protein kinase C (PKC) in the down-regulation of fibroblast proliferation in normal skin (NFb) and hyperplastic scar (SFb) by adrenaline.

METHODSHuman NFb and SFb cells were cultured in vitro. Phentolamine (in final concentrations of 0 and 3 x 10(-6) micromol/L) was added to the culture medium. One hour later, adrenaline in different final concentrations (0.00, 0.05, 0.10, 0.20 micromol/L) was added to the culture medium and incubated for 24 hours. The cellular proliferation activity and cell viability rate were determined with MTT. The cell culture supernatant was harvested for the determination of LDH activity to assess the toxicity of phentolamine and adrenaline. The phosph-PKC activity was determined with Western-blotting and was semiquantitatively analyzed.

RESULTS(1) After stimulation with adrenaline alone, or combined 0.20 micromol/L adrenaline with 3 x 10(-6) micromol/L phentolamine, the cell viability of both NFb and SFb decreased significantly (P < 0.05 or 0.01). (2) There was no difference in the LDH activity between the cells either stimulated by adrenaline in all concentrations or by combination of adrenaline and phentolamine (P > 0.05). (3) The phosphorylation of PKC in NFb and SFb cells stimulated by 0.05, 0.10, 0.20 micromol/L adrenaline was obviously higher than that before stimulation (P < 0.01). When phentolamine in the concentration of 3 x 10(-6) micromol/L was used alone for stimulation, the phosphorylation of PKC in NFb cells (123 +/- 5) was also evidently higher than that before stimulation (80 +/- 5, P < 0.01). But there was no such effect on SFb cells (P > 0.05). When adrenaline in the concentration of 0.05, 0.10 or 0.20 micromol/L was separately added together with phentolamine in the dose of 3 x 10(6) micromol/L for the stimulation, the phosphorylation of PKC in NFb and SFb cells was evidently lower than that when 3 different concentrations of adrenaline was used alone for stimulation (P < 0.01).

CONCLUSIONAdrenaline can inhibit the proliferation of NFb and SFb by activating PKC through binding alpha adrenaline receptor.

Cell Proliferation ; drug effects ; Cells, Cultured ; Cicatrix, Hypertrophic ; metabolism ; Down-Regulation ; Epinephrine ; adverse effects ; Fibroblasts ; cytology ; Humans ; Phentolamine ; adverse effects ; Phosphorylation ; Protein Kinase C ; metabolism ; Skin ; drug effects

OBJECTIVETo investigate the inhibitory effect of the Hedgehog signal pathway blocker (cyclopamine) on DU145 cells.

METHODSWe interfered DU145 cells with cyclopamine at the concentrations of 1, 10, 50 and 100 micromol/L and detected its inhibitory effect on the cells by MTT colorimetry assay at 24, 48 and 72 hours, as well as its effect on the cell cycle by flow cytometry. We also determined the difference in the mRNA expression of cyclin E between the experimental and control groups by RT-PCR at 48 hours after 50 +/- micromol/L cyclopamine intervention.

RESULTSCyclopamine inhibited the DU145 cells in a time- and dose-dependent manner, with inhibition rates of 7.42, 12.70 and 59.15% in the 10, 50 and 100 micromol/L groups respectively at 24 hours, significantly different from that of the blank control group (P < 0.05). It markedly suppressed the proliferation of the DU145 cells at >10 micromol/L at 24 hours. Flow cytometry showed an obviously increased proportion of stage G1 cells at the concentration of >10 micromol/L after 48-hour intervention, with statistically significant differences from the G1 cell proportions in the control, 10 micromol/L and 50 micromol/ L groups, which were (52.17 +/- 2.21)%, (60.13 +/- 2.75)% and (74.30 +/- 3.52)% respectively (P < 0.01). The apoptotic peak was elevated with the increased concentration of cyclopamine. The cyclin E mRNA expression of the DU145 cells was decreased by 61.90% at 48 hours after 50 micromol/L cyclopamine intervention as compared with the blank control group (P < 0.01).

CONCLUSIONCyclopamine can inhibit the proliferation of DU145 cells, and the mechanism may be related with its effect of down-regulating the cyclin E mRNA expression of DU145 cells and blocking them in stage G1. Cyclopamine can also induce the apoptosis of DU145 cells.

Apoptosis ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cyclin E ; metabolism ; Down-Regulation ; Flow Cytometry ; Humans ; Male ; Signal Transduction ; drug effects ; Veratrum Alkaloids ; pharmacology

The anti-cancer effects of betulinic acid (BA) on Jurkat cells and its in vitro mechanism were examined by using MTT assay. Apoptosis was detected by using Hoechst33258 staining and annexin-V/PI double-labeled cytometry. The effects of betulinic acid on the cell cycle of Jurkat cells were studied by propidium iodide method. RT-PCR and Western blotting were used to analyze the changes of cyclin D3, bcl-xl mRNA and protein levels in Jurkat cells after treatment with betulinic acid. Our results showed the proliferation of Jurkat cells was decreased in betulinic acid-treated group with a 24-h IC50 value being 70.00 mumol/L. Betulinic acid induced apoptosis of Jurkat cells in a time- and dose-dependent manner. The number of Jurkat cells treated with betulinic acid showed an increase in G(0)/G(1) phase and decrease in S phase. After treatment with 0, 20, 60, 100 mumol/L betulinic acid for 24 h, the number of Jurkat cells was increased from (31.00+/-1.25)% to (58.84+/-0.32)% in G(0)/G(1) phase, whereas it was decreased from (61.45+/-1.04)% to (35.82+/-1.95)% in S phase. PBMCs were less sensitive to the cytotoxicity of betulinic acid than Jurkat cells. The expressions of cyclin D3, bcl-xl mRNA and protein were decreased sharply in Jurkat cells treated with betulinic acid. It is concluded that betulinic acid is able to inhibit the proliferation of Jurkat cells by regulating the cell cycle, arrest cells at G(0)/G(1) phase and induce the cell apoptosis. The anti-tumor effects of betulinic acid are related to the down-regulated expression of cyclin D3 and bcl-xl.
Antineoplastic Agents, Phytogenic/*pharmacology ; Apoptosis/*drug effects ; Cell Proliferation/*drug effects ; Cyclin D3/metabolism ; Down-Regulation/drug effects ; Jurkat Cells ; Triterpenes/*pharmacology ; bcl-X Protein/metabolism

OBJECTIVETo explore the effects of carbendazim on the testicular development and spermatogenic function of male rats and its action mechanism.

METHODSForty clean-grade impubic male Wistar rats were equally randomized into a low-dose, a medium-dose, a high-dose and a control group, treated respectively with carbendazim at 20, 100 and 200 mg/kg (bw) and Tween-80 solution, all by oral gavage once a day for 80 days. After treatment, the rats were weighed, their testes and epididymides immediately excised, their morphological changes observed and the weights of the right testis and epididymis obtained. Sperm motility and counts in the left cauda epididymis were determined. Histopathological changes, cell apoptosis and the expression of Bcl-2/Bax in the testis were detected by HE staining, TUNEL and immunohistochemical SABC method.

RESULTSThe medium- and high-dose groups showed obviously atrophic testes and epididymides, marked histopathological abnormality of the testis, reduced weight of the right testis and epididymis, and decreased sperm motility and counts in the left cauda epididymis (P < 0.01). With the increasing dose of carbendazim, the apoptosis rate and Bax expression were significantly raised, while the expression of Bcl-2 significantly decreased (P < 0.05, P < 0.01).

CONCLUSIONCarbendazim affects the testicular development and spermatogenic function of male rats, and the mechanism may involve cell apoptosis induced by down-regulation of Bcl-2 and up-regulation of Bax.

Animals ; Apoptosis ; drug effects ; Benzimidazoles ; pharmacology ; Carbamates ; pharmacology ; Down-Regulation ; Male ; Rats ; Rats, Wistar ; Spermatogenesis ; drug effects ; Testis ; drug effects ; growth & development ; bcl-2-Associated X Protein ; metabolism