OBJECTIVETo investigate the changes of proto-oncogene c-fos, c-jun mRNA expression in angiotensin II (Ang II)-induced hypertrophy and effects of tanshinone II A (Tan) in the primary culture of neonatal rat cardiomyocytes.

METHODTwelve neonatal Wistar rats aged one day old of clean grade and both sexes were selected to isolate and culture cardiomyocytes. The cardiomyocytes were divided into: normal control group, Ang II (10(-6) mol x L(-1)) group, Ang II (10(-6) mol x L(-1)) +Tan (10(-8) g x L(-1)) group, Ang II (10(-6) mol x L(-1)) + valsartan (10(-6) mol x L(-1)) group, Tan (10(-8) g x L(-1)) group, valsartan (10(-6) mol x L(-1)) group. The cardiomyocyte size was determined by phase contrast microscope, the rate of protein synthesis in cardiomyocytes was measured by 3H-leucine incorporation. The c-fos, c-jun mRNA expression of cardiomyocytes were assessed using reverse transcription polymerase chain reaction (RT-PCR).

RESULTAng II was added to the culture medium and 30 min later, the c-fos, c-jun mRNA expression of cardiomyocytes increased significantly (P < 0. 01). After Ang II took effect for 24 h, the rate of protein synthesis in Ang II group increased more prominently than that in normal control group (P < 0.01). After Ang II took effect for 7 days, the size of cardiomyocyte in Ang II group increased obviously (P < 0. 05). If tanshinone II or valsartan was added to the culture medium before Ang II, both of them could inhibit the increase of c-fos, c-jun mRNA expression (P < 0.01), cardiomyocyte protein synthesis rate (P < 0.01), and cardiomyocyte size (P < 0.05) induced by Ang II.

CONCLUSIONTanshinone II could ameliorate Ang II-induced cardiomyocytes hypertrophy by inhabiting c-fos, c-jun mRNA expression.

Angiotensin II ; biosynthesis ; pharmacology ; Animals ; Cardiomegaly ; chemically induced ; metabolism ; pathology ; Diterpenes, Abietane ; Gene Expression Regulation ; drug effects ; Genes, fos ; genetics ; Genes, jun ; genetics ; Myocytes, Cardiac ; drug effects ; metabolism ; pathology ; Phenanthrenes ; pharmacology ; Proto-Oncogene Proteins c-fos ; genetics ; Proto-Oncogene Proteins c-jun ; genetics ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Wistar ; Tetrazoles ; pharmacology ; Valine ; analogs & derivatives ; pharmacology ; Valsartan

To elucidate the endocrine mechanism of human parturition, the expression of c-Jun and c-Fos mRNA were examined in relation to estrogen receptor (ER) and progesterone receptor (PR) in human myometrium. c-Jun mRNA was detected in all myometrial tissues (n=5) during labor but not before labor (n=5) and in oxytocin-resistant postterm pregnancy (n=3). c-Fos mRNA was detected in only one myometrial tissue from a woman in labor. The distribution and intensity of immunostaining for ER and PR were semiquantitatively scored. During the late pregnancies, no significant difference was seen in the receptor scores for myometrial ER and PR between the patients who experienced labor and those who did not. Receptor scores for ER and PR were significantly lower in postterm pregnancy than in late pregnancy, regardless of the labor status. These data suggest that there are no changes in ER and PR in human myometrium during parturition. On the other hand, postterm pregnancy is associated with low ER and PR. c-Jun, induced during labor without changes in ER and PR, may play a role as a signaling mechanism in human myometrium.
Adult ; Blotting, Northern ; Female ; Genes, jun/genetics* ; Human ; Immunohistochemistry ; Labor/metabolism* ; Myometrium/metabolism* ; Myometrium/cytology ; Pregnancy ; RNA, Messenger/analysis ; Receptors, Estrogen/metabolism* ; Receptors, Progesterone/metabolism* ; Reference Values

The expression of the p53 protein (p53) was compared with those of several oncogenes including c-fos (Fos), c-jun (Jun), and epidermal growth factor receptor (EGFR1) using immunohistochemistry in frozen and paraffin-embedded sections of 25 basal cell carcinomas (BCCs) to find out any correlation between p53 and oncogenes in the pathogenesis of human BCC. In normal skin, positive reactions were obtained for EGFR1 and Fos, while p53 and Jun were negative in all cases. In the lesions, EGFR1 was observed in all cases and p53 was positive in 9 of 25 (36%). Fos was expressed in 21 of 25 (84%) and four negative cases were all p53-positive; this negative correlation between p53 and Fos staining was statistically significant (P< 0.01). Jun was detected in 14 of 20 (70%) and no significant relationship was observed between the expression of Jun and Fos or p53. These data suggest the possibility of down regulation of Fos expression by high levels of p53 protein. Further work is necessary to determine the mechanism of this interaction.
Aged ; Carcinoma, Basal Cell/chemistry/*genetics ; Comparative Study ; Female ; Gene Expression ; Genes, fos ; Genes, jun ; Genes, p53 ; Human ; Immunohistochemistry ; Male ; Middle Age ; Oncogene Protein p65(gag-jun)/analysis ; Oncogene Proteins v-fos/analysis ; *Oncogenes ; Protein p53/analysis ; Receptor, Epidermal Growth Factor/analysis ; Skin Neoplasms/chemistry/*genetics

Thrombospondin-1 (TSP-1), a multifunctional protein that is able to function as a negative regulator of solid tumor progression and angiogenesis, is normally present at a very low level but rapidly elevated in pathological tissues. To understand the cellular regulation of TSP-1 expression, the mode of it's expression in Hep3B, SK-HEP-1, and porcine aortic endothelial (PAE) cells was examined in the presence of all-trans retinoic acid (ATRA), interleukin-6 (IL-6), interferon-gamma (IFN-gamma), or phorbol 12-myristate 13-acetate (PMA). ATRA or IL-6 induced a dose-dependent increase of TSP-1 protein and mRNA levels in PAE cells, while they negatively regulated TSP-1 expression in the Hep3B and SK-HEP-1 cells. In contrast, PMA showed just the opposite effects on the TSP-1 expression in the same cells. IFN-gamma had little effect on TSP-1 level in Hep3B and PAE cells. The TSP-1 expression in SK-HEP-1 cells by these agents showed a close resemblance to that of liver cells rather than that of the endothelial cell line. Possible TSP-1 promoter-mediated responses by ATRA, IL-6, IFN-gamma, or PMA in Hep3B and PAE cells examined with luciferase activity of TSP-LUC reporter plasmid showed that levels of TSP-1 promoter activity were lower than that of the expressed TSP-1 protein and mRNA levels. Transfection of c-Jun and/or RARalpha expression vectors into Hep3B and PAE cells resulted in the enhanced TSP-1 promoter activity as well as the increments of of its protein and mRNA level. These results suggest that regulatory agents-induced TSP-1 expression may be attributed to mRNA stability and/or translational activation in concert with transcriptional activation and TSP-1 expression may be independently controlled via each signal pathway stimulated by PMA or ATRA.
Animal ; Cell Line ; Endothelium, Vascular/cytology/drug effects/metabolism ; *Gene Expression Regulation/drug effects ; Genes, Reporter ; Genes, jun ; Human ; Immunoblotting ; Interferon Type II/pharmacology ; Interleukin-6/pharmacology ; *Promoter Regions (Genetics) ; Proto-Oncogene Proteins c-jun/genetics/metabolism ; Receptors, Retinoic Acid/genetics/metabolism ; Recombinant Fusion Proteins/metabolism ; Tetradecanoylphorbol Acetate/pharmacology ; Thrombospondin 1/*genetics/metabolism ; Transcription, Genetic ; Tretinoin/pharmacology

OBJECTIVEIt was reported previously that genistein could inhibit proliferation of human ovarian carcinoma cell line SKOV(3), but mechanism was not clear. There is a close relationship between EGFR mediated signal transduction pathway and the development of ovarian tumor. This study aimed to investigate the effects of genistein on the EGFR mediated signal transduction pathway and to clarify its mechanisms of proliferation inhibition on human ovarian carcinoma cell line SKOV(3) and its xenograft in nude mice.

METHODSThe expression of c-erbB-2 protein was determined using immunocytochemistry. The expressions of c-jun and c-fos protein were determined using Western blotting. The expression of c-erbB-2, c-raf-1, c-jun and c-fos mRNA were tested by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTSThe expression of c-erbB-2, c-raf-1 and its downstream gene c-jun and c-fos were decreased at mRNA level in the 20 micromol/L genistein group. The expression of c-erbB-2 protein were decreased, its average absorbency (A) were decreased after treatment of SKOV(3) with 20 micromol/L genistein for 48 h, reached at 0.42 +/- 0.02 (P < 0.05). Western blotting demonstrated that the expressions of c-jun and c-fos protein were decreased gradually after being treated with 20 micromol/L genistein for 12 - 72 h.

CONCLUSIONSGenistein could down-regulate the expression of two key genes, c-erbB-2 and c-raf-1 at mRNA and protein level in the EGFR mediated signal transduction pathway, and down-regulate the expression of its downstream nuclear transcription factors c-jun and c-fos at mRNA and protein level. It is suggested that interfering the expressions of some key signal molecules in EGFR mediated signal transduction system by genistein may account for its molecular foundation of proliferation inhibition in ovarian carcinoma.

Animals ; Antineoplastic Agents ; pharmacology ; Cell Line, Tumor ; Female ; Gene Expression Regulation, Neoplastic ; Genes, fos ; Genes, jun ; Genistein ; pharmacology ; Humans ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Transplantation ; Ovarian Neoplasms ; metabolism ; pathology ; Proto-Oncogene Proteins c-fos ; biosynthesis ; genetics ; Proto-Oncogene Proteins c-jun ; biosynthesis ; genetics ; Proto-Oncogene Proteins c-raf ; biosynthesis ; genetics ; RNA, Messenger ; biosynthesis ; genetics ; Receptor, Epidermal Growth Factor ; metabolism ; Receptor, ErbB-2 ; biosynthesis ; genetics ; Signal Transduction ; drug effects

OBJECTIVEMercury (Hg), as one of the priority pollutants and also a hot topic of frontier environmental research in many countries, has been paid higher attention in the world since the middle of the last century. Guizhou Province (at N24 degrees 30'-29 degrees 13', E103 degrees 1'-109 degrees 30', 1 100 m above the sea level, with subtropical humid climate) in southwest China is an important mercury production center. It has been found that the mercury content in most media of aquatics, soil, atmosphere and in biomass of corns, plants and animals, is higher than the national standard. The present study aims to explore the influence of mercury pollution on the health of local citizens.

METHODSThe effect of rice from two mercury polluted experimental plots of Guizhou Province on the expression of c-jun mRNA in rat brain and c-jun protein in cortex, hippocampus and ependyma was observed using reverse transcription polymerase chain reaction (RT-PCR) and immunocytochemical methods.

RESULTSThe results showed that the mercury polluted rice induced expression of c-jun mRNA and its protein significantly. Selenium can reduce Hg uptake, an antagonism between selenium and mercury on the expression of c-jun mRNA and c-jun protein.

CONCLUSIONc-jun participates in the toxicity process of brain injury by mercury polluted rice, the expression of c-jun mRNA in brain, and c-jun protein in rat cortex and hippocampus can predict neurotoxicity of mercury polluted rice. People should be advised to be cautious in eating any kind of Hg-polluted foods. To reveal the relationship between c-jun induction and apoptosis, further examinations are required.

Animals ; Atmosphere ; Base Sequence ; Biomass ; Brain ; drug effects ; metabolism ; China ; Food Contamination ; Genes, jun ; genetics ; Immunohistochemistry ; Mercury ; analysis ; toxicity ; Oryza ; chemistry ; RNA, Messenger ; genetics ; metabolism ; Rats ; Reverse Transcriptase Polymerase Chain Reaction ; Soil Pollutants ; analysis ; toxicity ; Time Factors

OBJECTIVETo explore JunB gene expression in spleen cells of mice after the whole body irradiation as well as in normal hematopoietic and leukemia cells in the primary culture after different dosages of X-ray irradiation.

METHODSSpleen cells were isolated from the mice irradiated with 3 Gy X-rays. Primary cultured cells from mice were incubated in different intervals after X-irradiation at different dosages. Total RNA was extracted from the cells and the fluctuation of JunB mRNA level was assessed by the RNA ratio of JunB/beta-actin measured by quantitative Northern blot hybridization.

RESULTSAfter the mice were exposed to 3 Gy X-rays irradiation, JunB expression in spleen cells was remarkably and rapidly increased, and reached its peak 0.5 h later in C3H/He mice and 1 h later in Balb/c mice. In the primary culture of normal spleen and leukemia cells, JunB mRNA levels increased 30 min after irradiation. The enhanced levels of JunB mRNA were returned to a normal level within 240 min after irradiation.

CONCLUSIONSJunB gene is responsive to ionizing irradiation and is induced at immediate-early phase after the stimulation. This suggests that the JunB gene plays an important role in the early process of the cells against radiation.

Actins ; genetics ; Animals ; Blotting, Northern ; Cell Line ; Cells, Cultured ; Gamma Rays ; Gene Expression ; radiation effects ; Genes, jun ; genetics ; Mice ; Mice, Inbred BALB C ; Mice, Inbred C3H ; RNA, Messenger ; Spleen ; radiation effects

OBJECTIVETo study the effects of selenium on DNA damage, apoptosis and c-myc, c-fos, and c-jun expression in rat hepatocytes.

METHODSSodium selenite at the doses of 5, 10, and 20 micromol/kg was given to rats by i.p. and there were 5 male SD rats in each group. Hepatocellular DNA damage was detected by single cell gel electrophoresis (or comet assay). Hepatocellular apoptosis was determined by TUNEL (TdT-mediated dUTP nick end labelling) and flow cytometry. C-myc, c-fos, and c-jun expression in rat hepatocytes were assayed by Northern dot hybridization. C-myc, c-fos, and c-jun protein were detected by immunohistochemical method.

RESULTSAt the doses of 5, 10, and 20 micromol/kg, DNA damage was induced by sodium selenite in rat hepatocytes and the rates of comet cells were 34.40%, 74.80%, and 91.40% respectively. Results also showed an obvious dose-response relationship between the rates of comet cells and the doses of sodium selenite (r=0.9501, P<0.01). Sodium selenite at the doses of 5, 10, and 20 micromol/kg caused c-myc, c-fos, and c-jun overexpression obviously. The positive brown-yellow signal for proteins of c-myc, c-fos, and c-jun was mainly located in the cytoplasm of hepatocytes with immunohistochemical method. TUNEL-positive cells were detected in selenium-treated rat livers. Apoptotic rates (%) of selenium-treated liver cells at the doses of 5, 10, and 20 micromol/kg were (3.72 +/- 1.76), (5.82 +/- 1.42), and (11.76 +/- 1.87) respectively, being much higher than those in the control. Besides an obvious dose-response relationship between apoptotic rates and the doses of sodium selenite (r=0.9897, P<0.01), these results displayed a close relationship between DNA damage rates and apoptotic rates, and the relative coefficient was 0.9021, P<0.01.

CONCLUSIONSelenium at 5-20 micromol/kg can induce DNA damage, apoptosis, and overexpression of c-myc, c-fos, and c-jun in rat hepatocytes.

Animals ; Apoptosis ; drug effects ; Blotting, Northern ; Comet Assay ; DNA Damage ; Dose-Response Relationship, Drug ; Genes, fos ; drug effects ; genetics ; Genes, jun ; drug effects ; genetics ; Genes, myc ; drug effects ; genetics ; Hepatocytes ; drug effects ; pathology ; Male ; Nucleic Acid Hybridization ; Rats ; Rats, Sprague-Dawley ; Selenium ; pharmacology ; Sodium Selenite ; pharmacology

OBJECTIVETo study influence of lanthanum chloride (LaCl(3)) on the expression of immediate early genes (IEGs) including c-jun, early growth response gene 1 (Egr1) and activity-regulated cytoskeletal gene (Arc) in the hippocampus of rats, and discuss the mechanism of LaCl(3) undermining learning and memory capability.

METHODSForty female Wistar adult rats were divided into control group, low LaCl(3)-contaminated group (0.25%), medium LaCl(3)-contaminated group (0.50%), and high LaCl(3)-contaminated group (1.00%) by randomized design. Each group had ten female rats along with five male rats and mated by the ratio of 2:1. The amounts of pups in the above four groups were 80, 83, 78 and 75 separately. The pups in respective group were La-dyed by lactation, and then the pups in LaCl(3)-contaminated groups drank 0.25%, 0.50% and 1.00% LaCl(3) separately for one month. Learning and memory capability of pups were measured in jumping stairs experiment. Hippocampal lanthanum content was determined by inductively coupled plasma mass spectrometry (ICP-MS). Hippocampal c-jun, Egr1 and Arc mRNA expression was detected by RT-PCR, and corresponding protein expression was measured by Western blotting method.

RESULTSIn the jumping stairs experiment, pups in 0.25%, 0.50% and 1.00% LaCl(3)-contaminated groups respectively made (1.75 ± 0.71), (2.38 ± 0.92) and (3.00 ± 0.76) mistakes; significantly higher than control group (1.25 ± 0.46) (q values were 4.386, 6.793, P < 0.05). However, the incubation period of 0.25%, 0.50% and 1.00% LaCl(3)-contaminated groups were (174.13 ± 33.72), (139.25 ± 45.83) and (75.50 ± 18.56) respectively, which were all significantly lower than that of control group (206.75 ± 20.47) (q values were 2.958, 6.121, 11.902, P < 0.05). Hippocampal c-jun mRNA expression were (0.89 ± 0.08), (0.77 ± 0.12), (0.58 ± 0.14) and (0.29 ± 0.10); while the c-jun protein expression were (0.72 ± 0.13), (0.64 ± 0.11), (0.43 ± 0.11) and (0.31 ± 0.14), and the Egr1 mRNA expression were (0.78 ± 0.09), (0.61 ± 0.13), (0.53 ± 0.10) and (0.22 ± 0.08), Egr1 protein expression were (0.65 ± 0.18), (0.40 ± 0.15), (0.32 ± 0.13) and (0.14 ± 0.09) in 0.25%, 0.50% and 1.00% LaCl(3)-contaminated groups; and all of which presented a dose-effect relationship that the correlation coefficients of these parameters with dose were -0.900 (t = 11.309, P = 0.000), -0.969 (t = 7.058, P = 0.000), -0.898 (t = 11.179, P = 0.000) and -0.962 (t = 6.739, P = 0.000).

CONCLUSIONLaCl(3) undermines the learning and memory capability of rats, which is possibly related to lower expression of c-jun and Egr1 gene and protein induced by lanthanum in hippocampus.

Animals ; Early Growth Response Protein 1 ; metabolism ; Female ; Gene Expression ; Genes, Immediate-Early ; drug effects ; genetics ; Hippocampus ; drug effects ; metabolism ; Lanthanum ; pharmacology ; Learning ; drug effects ; Male ; Memory ; drug effects ; Proto-Oncogene Proteins c-jun ; metabolism ; Rats ; Rats, Wistar

In order to investigate the mechanism of mechanical stress-mediated arterial remodeling, we studied the pressure-induced expression of immediate-early response gene product c-Jun in common carotid arteries in rats. The common carotid arteries were perfused with both high pressure (160 mmHg) and normal pressure (80 mmHg) for 0.5, 1, 3 and 6 hours. Expression of immediate-early response gene product c-Jun in the arteries was examined by immunohistochemistry and computer image processing. c-Jun was weakly expressed at 1 h, then increased at 3 h and 6 h after exposure of the arteries to normal pressure. Positive immunohistochemical product of c-Jun appeared in the arteries at 0.5 h after the onset of high pressure, then it increased markedly till 6 h. There was significant difference between the two groups. These results indicate that expression of c-Jun of the arteries can be induced by pressure, which may play an important role in mechanical stress-mediated arterial remodeling.
Animals ; Biomechanical Phenomena ; Carotid Artery, Common ; cytology ; metabolism ; physiology ; Genes, Immediate-Early ; Male ; Muscle, Smooth, Vascular ; cytology ; metabolism ; Pressure ; Proto-Oncogene Proteins c-jun ; biosynthesis ; genetics ; Rats ; Rats, Sprague-Dawley ; Stress, Mechanical