BACKGROUND5α-Reductase inhibitors (5α-RI) act by inhibiting the conversion of testosterone to dihydrotestosterone (DHT), thereby preventing DHT induced benign prostatic hyperplasia. The existing 5α-RIs can be classified into two types: competitive and noncompetitive. Currently, limited evidence is available concerning the effect differences between the two types of 5α-RI on androgens. The purpose of this study was to assess the effects of competitive and noncompetitive 5α-RIs on serum and intra-prostatic androgens in beagle dogs.

METHODSTwenty beagles with spontaneous benign prostatic hyperplasia were randomly allocated into two groups: epristeride group (n = 10) in which beagles were treated with epristeride at 1 mg/kg once a day for 3 months, and finasteride group (n = 10) in which beagles were treated with finasteride at 1 mg/kg once a day for 3 months. The levels of intra-prostatic testosterone and DHT were measured before treatment and on day one after three months medication. Serum levels of testosterone and DHT were measured at the same time points. Changes in androgen levels before and after treatment were analyzed, and comparisons were made within each treatment group and between treatment groups.

RESULTSAfter 3-month treatment, serum and intra-prostatic DHT levels all decreased significantly in both the epristeride and finasteride groups. The change of DHT in serum was significantly higher in the finasteride group (-14% and -43% in epristeride and finasteride groups respectively, with P < 0.001); however there was no significant difference in the changes of intra-prostatic DHT between the two groups (-47% and -51% in epristeride and finasteride groups, respectively, P = 0.304). The decreases in DHT levels were accompanied by reciprocal increases in serum and intra-prostatic testosterone levels. Changes of testosterone were significantly higher in finasteride group both in serum (20% and 42% in epristeride and finasteride groups, respectively, P < 0.001) and in prostate tissue (18% and 29% in epristeride and finasteride groups, respectively, P = 0.004).

CONCLUSIONSTwo types of 5α-RI have similar effects in reducing DHT in prostate tissue in beagles. Competitive 5α-RI may reduce serum DHT to a greater scale, and significantly increase testosterone in beagle serum and prostate.

5-alpha Reductase Inhibitors ; pharmacology ; Androgens ; blood ; metabolism ; Androstadienes ; pharmacology ; Animals ; Dihydrotestosterone ; blood ; metabolism ; Dogs ; Finasteride ; pharmacology ; Male ; Prostate ; drug effects ; metabolism

OBJECTIVETo identify the role of 5alpha-reductase in the spermatogenesis of male rats by studying the effect of two 5alpha-reductase inhibitors, Epristeride and Finasteride, on the spermatogenesis in male Sprague-Dawley (SD) rats.

METHODSChanges in the weight of the testis, serum testosterone and dihydrotestosterone levels, epididymal sperm count, and reproductive function were observed and analyzed after the two 5alpha-reductase inhibitors were administered to male SD rats orally.

RESULTSThe experiment showed that in comparison with control animals, both the two 5alpha-reductase inhibitors: 1. suppressed the development of the prostate and reduced the weight of the testis in the experimental groups (P < 0.05); 2. decreased the serum level of dihydrotestosterone and enhanced testosterone; 3. inhibited epididymal sperm count and productive function.

CONCLUSIONHigh dosages of the 5alpha-reductase inhibitor, Epristeride, can suppress the development of the prostate and reduce the weight of the testis, decrease dihydrotestosterone, and inhibit spermatogenesis and productive function in male rats.

5-alpha Reductase Inhibitors ; Androstadienes ; pharmacology ; Animals ; Dose-Response Relationship, Drug ; Finasteride ; pharmacology ; Male ; Rats ; Rats, Sprague-Dawley ; Spermatogenesis ; drug effects

OBJECTIVE: To investigate the effects of intranasal steroid on nasal mucosa in rat model of allergic rhinitis (AR). METHOD: Thirty-six SD rats were randomly divided into three groups (each included 12 rats): the intranasal steroid group(group A),the allergic rhinitis group(group B) and the normal control group(group C). AR model was reproduced by ovalbumin in group A and B. The control group was allergized by NS instead of ovalbumin. Group A was used steroid spray in nasal and Group B and C was used normal saline. Then ,after the last provocation,the allergic symptoms were evaluated,the number of eosinophil (EOS) of the rats' nasal mucosa was counted under hematoxylineosin staining and the goblet cells was counted under alcian blue-periodic acid-Schiff staining. The morphological changes of the rats' nasal mucosa were observed by scanning electron microscope. RESULT: Compared with group B,the inhibition of nasal symptoms was found after used of steroid spray in group A. The EOS and the goblet cells in group A was significantly different with that in Group B (P < 0.05), but no significant differences compared with group C (P > 0.05). Observed by scanning electron microscope, the cilia of the epithelium in group B were significantly lodging, disoriented, winding and secreting,while the cilia of the epithelium in Group A and C had similar appearance. CONCLUSION Intranasal steroid spray can relieve symptoms and inflammatory conditions of nasal mucosa in allergic rhinitis, and can repair injured nasal mucosa cilia.
Androstadienes ; pharmacology ; Animals ; Anti-Inflammatory Agents ; pharmacology ; Cilia ; ultrastructure ; Disease Models, Animal ; Inflammation ; Nasal Mucosa ; drug effects ; pathology ; Rats ; Rats, Sprague-Dawley ; Rhinitis, Allergic, Perennial ; drug therapy ; pathology

OBJECTIVE: To investigate the expression and distribution of aquaporin 5 (AQP5) in allergic rhinitis (AR) treated by fluticasone propionate and levocabastine. METHOD: Forty Wistar rats were divided randomly into AR (n=30) and control groups (n=10). After AR models were established, the AR rats were divided evenly into F group, L group and AR control group. Three groups were treated respectively for 28 days, then the expression of AQP5 in nasal mucous membrane were detected by immunohistochemistry assay. RESULT: The distribution of AQP5 was consistent in all groups. The expression of AQP5 in F group was significantly different from L group and AR group (P<0.05), while there was no significant difference between that of AR group and L group (P>0.05). The expression of AQP5 in L group was significantly different from that in control group (P<0.05). CONCLUSION High expressions of AQP5 in rat with AR indicated the positive correlation between AQP5 and AR. AQP5 might be one of pathological factors of AR concerned with glands excessive secretion and tissue edema. Glucocorticoid can down-regulate the expression of AQP5, but H1-receptor antagonist can not reduce the expression of AQP5.
Androstadienes ; pharmacology ; Animals ; Aquaporin 5 ; metabolism ; Fluticasone ; Nasal Mucosa ; drug effects ; metabolism ; pathology ; Piperidines ; pharmacology ; Rats ; Rats, Wistar ; Rhinitis, Allergic, Perennial ; metabolism ; pathology

The chronic myelogenous leukemic K562 cell line carrying Bcr-Abl tyrosine kinase is considered as pluripotent hematopoietic progenitor cells expressing markers for erythroid, granulocytic, monocytic, and megakaryocytic lineages. Here we investigated the signaling modulations required for induction of erythroid differentiation of K562 cells. When the K562 cells were treated with herbimycin A (an inhibitor of protein tyrosine kinase), ras antisense oligonucleotide, and PD98059 (a specific inhibitor of MEK), inhibition of ERK/MAPK activity and cell growth, and induction of erythroid differentiation were observed. The ras mutant, pZIPRas61leu-transfected cells, K562-Ras61leu, have shown a markedly decreased cell proliferation rate with approximately 2-fold doubling time, compared with the parental K562 cells, and about 60% of these cells have shown the phenotype of erythroid differentiation. In addition, herbimycin A inhibited the growth rate and increased the erythroid differentiation, but did not affect the elevated activity of ERK/MAPK in the K562-Ras61leu cells. On the other hand, effects of PD98059 on the growth and differentiation of K562-Ras61leu cells were biphasic. At low concentration of PD98059, which inhibited the elevated activity of ERK/MAPK to the level of parental cells, the growth rate increased and the erythroid differentiation decreased slightly, and at high concentration of PD98059, which inhibited the elevated activity of ERK/MAPK below that of the parental cells, the growth rate turned down and the erythroid differentiation was restored to the untreated control level. Taken together, these results suggest that an appropriate activity of ERK/MAPK is required to maintain the rapid growth and transformed phenotype of K562 cells.
Androstadienes/pharmacology ; Ca(2+)-Calmodulin Dependent Protein Kinase ; Cell Differentiation/drug effects ; Enzyme Inhibitors/pharmacology ; Erythroid Progenitor Cells/physiology* ; Erythroid Progenitor Cells/cytology ; Erythropoiesis* ; Flavones/pharmacology ; Human ; K562 Cells ; Leukemia, Myeloid/pathology ; Oligonucleotides, Antisense/pharmacology ; Quinones/pharmacology ; ras Proteins/metabolism*

The present study was to explore the effects of insulin on proliferation of skeletal myoblast cells in rats. Separated and cultured primary skeletal myoblast cells from rats were treated by insulin. By means of the incorporation of (3)H-TdR, BrdU assay and MTT assay, the proliferation of skeletal myoblast cells was detected. Western blot was used to check the phosphorylation of Akt and ERK of myoblast cells. The results showed that insulin significantly promoted the incorporation of (3)H-TdR into cultured skeletal myoblast cells in a dose-dependent manner. MTT assay and BrdU assay also showed insulin promoted the proliferation of skeletal myoblast cells. The promotion of skeletal myoblast cells proliferation by insulin was inhibited by PI3K inhibitor wortmannin or MEK inhibitor U0126, and the same phenomenon was shown in L6 and C2C12 cells. Also, insulin increased the phosphorylation of Akt and ERK in myoblast cells. These results suggest that insulin may promote proliferation of skeletal myoblast cells through PI3K/Akt and MEK/ERK pathways.
Androstadienes ; pharmacology ; Animals ; Butadienes ; pharmacology ; Cell Proliferation ; Cells, Cultured ; Enzyme Inhibitors ; pharmacology ; Insulin ; pharmacology ; MAP Kinase Signaling System ; Myoblasts, Skeletal ; cytology ; drug effects ; Nitriles ; pharmacology ; Phosphatidylinositol 3-Kinases ; metabolism ; Phosphorylation ; Proto-Oncogene Proteins c-akt ; metabolism ; Rats

The objective of study was to compare the influences of wortmannin on platelet aggregation and platelet membrane surface glycoproteins GPIb expression after thrombin receptor activation, and to investigate the role of phosphatidylinositol 3-kinase (PI3-K) and myosin light chain kinase (MLCK) in the course of thrombin receptor activation. Peptide SFLLRN (PAR1-AP) and AYPGKF (PAR4-AP) were used for stimulating platelet, and the changes of platelet aggregation and GPIb were analyzed with 100 nmol/L wortmannin (inhibitor of PI3-K) and 10 micromol/L wortmannin (inhibitor of MLCK). The results indicated that the platelet activation was influenced by either concentration of wortmannin in response to PAR stimulation. Platelet aggregation was apparently inhibited by 10 micromol/L wortmannin through both PAR peptides, and was slightly inhibited by 100 nmol/L wortmannin only under PAR1-AP activation. In addition, GPIbalpha internalization was partly inhibited by 100 nmol/L wortmannin in response to PAR1 (p < 0.05 at 1, 2, 5 min) and PAR4 (p < 0.05 at 2, 5, 10 min) activation. Meanwhile, 10 micromol/L wortmannin induced little change for GPIbalpha centralisation in the course of PAR activation, with a delayed restoration of surface GPIbalpha observed under PAR1-AP activation, and no change of GPIbalpha redistribution existed under PAR4-AP activation. It is concluded that the different roles of PI3-K and MLCK exist in the course of thrombin receptor activation. PI3-K accelerates the short course of GPIb centralisation for two PAR signal pathways, while MLCK inhibits the restoration of GPIbalpha in PAR1 pathway.
Adult ; Androstadienes ; pharmacology ; Female ; Humans ; Male ; Myosin-Light-Chain Kinase ; metabolism ; Phosphatidylinositol 3-Kinase ; metabolism ; Platelet Activation ; drug effects ; Platelet Aggregation ; Receptors, Thrombin ; metabolism ; physiology ; Signal Transduction

OBJECTIVE: To investigate the dynamic process of the nasal mucosal remodeling, and the effect of the fluticasone propionate (FP) to remodeling, by establish animal model of allergic rhinitis (AR). METHOD: One hundred and twenty Sprague-Dawley (SD) rats were randomly divided into three groups: the normal Group A used as controls and experimental groups: Group B and C, each group had 40 rats. After the animal model were established successfully by OVA+ Al (OH)3 and disposed, then, the dynamic process of the nasal mucosal remodeling was observed, through HE staining and transmission electron microscopic section in special times. RESULT: The Group B, C nasal epithelium and cilia were not complete, eosinophil-based inflammatory cell infiltration, basement membrane thickening, collagen deposition, and a small amount of fibrosis could be found, but the structure of cells were not damaged. While those changes could not be observed in the Group A. The morphological changes of the nasal mucosa of Group B aggravated gradually under persistent allergen exposure, even stripped to the basement membrane in whole epithelial layers, cell and tissue structure were destroyed seriously. The morphological changes of nasal mucosa of Group C did not further increase, but still showed varying degrees of cilia arranged in uneven fashion, basement membrane thickening, collagen deposition and fibrous hyperplasia after treatment by FP. CONCLUSION Remodeling happens in the nasal mucosa, which would be aggravated, and even becomes irreversible if the allergen exposure continues persistently. The FP can relieve the clinical symptoms, slow down and even reverse the remodeling of AR. And it is ineffective when the changes become irreversible.
Androstadienes ; pharmacology ; Animals ; Disease Models, Animal ; Female ; Fluticasone ; Male ; Nasal Mucosa ; drug effects ; pathology ; Rats ; Rats, Sprague-Dawley ; Rhinitis, Allergic, Perennial ; immunology ; pathology

The observation that ascorbate known to retain pro-oxidant properties induces cell death in a number of immortal cell lines, led us to examine its mechanism and whether it is involved in oxidative stress injury in such asocorbate-enriched tissue cells as hepatocytes. In rat liver homogenates, higher concentrations (1 and 3 mM) of ascorbate suppressed lipid peroxide productions but lower concentrations (0.1 and 0.3 mM) did not. In contrast to the homogenate, ascorbate increased lipid peroxide production in liver slices in a concentration dependant manner. Iso-ascorbate, the epimer of ascorbate did not cause an increase the oxidative stress in liver slices. This differential effect between homogenates and liver slices implies that cellular integrity is required for ascorbate to induce oxidative stress. Wortmannin, an inhibitor of the GLUT (glucose transporter) thought to transport dehydroascorbate into cells, inhibited [14C]- ascorbate uptake and suppressed oxidative stress in liver slices. Wortmannin suppressed that [14C]- ascorbate uptake by GLUT following oxidation to [14C]dehydroascorbate. Taken together, these observations support our hypothesis that ascorbate is oxidized to dehydroascorbate by molecular oxygen in solution (i.e., plasma and culture medium) which is then carried into hepatocytes (via a GLUT) where it is reduced back to ascorbate causing oxidative stress.
Androstadienes/pharmacology ; Animals ; Ascorbic Acid/*metabolism/*pharmacology ; Biological Transport ; Edetic Acid/pharmacology ; Glutathione/*metabolism ; In Vitro ; Liver/*drug effects/*metabolism ; Male ; Oxidation-Reduction/drug effects ; Oxidative Stress/*drug effects ; Rats ; Rats, Sprague-Dawley ; Thiobarbituric Acid Reactive Substances/metabolism ; Time Factors

OBJECTIVETo investigate the effect and mechanism of the antihyperglycemic agent metformin on the expression of phosphoenolpyruvate carboxykinase (PEPCK) gene in hepatocytes and to determine whether the effects of metformin in hepatocytes are transmitted throughout the known insulin signaling pathways.

METHODSConfluent H4IIE rat heptoma cells were cultured for 16 h with 0.1 mmol/L metformin either in absence or presence of 0.1 nmol/L insulin, and then stimulated with various agents. The expression of PEPCK gene was examined by Northern blot analysis.

RESULTSTherapeutic concentrations of metformin significantly inhibited basal PEPCK mRNA expression and also decreased cAMP and dexamethasone induced PEPCK gene expression through interaction with insulin. In the presence of insulin signaling pathway inhibitors wortmannin and UO126, metformin reduced PEPCK mRNA levels, but wortmannin blocked inhibitory regulation of insulin on PEPCK gene expression.

CONCLUSIONMetformin inhibits PEPCK gene expression via either an insulin-independent or an interacting-with-insulin manner. The results suggest that a possible mechanism by which metformin reduces gluconeogenesis could be associated with the inhibition of PEPCK gene expression.

Androstadienes ; pharmacology ; Cells, Cultured ; Gene Expression ; drug effects ; Hepatocytes ; drug effects ; enzymology ; Humans ; Hypoglycemic Agents ; pharmacology ; Metformin ; pharmacology ; Phosphatidylinositol 3-Kinases ; physiology ; Phosphoenolpyruvate Carboxykinase (GTP) ; genetics ; RNA, Messenger ; analysis ; Tumor Cells, Cultured