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1.
Acta Diabetol ; 44(1): 6-13, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17357879

ABSTRACT

The KK/Ta strain serves as a suitable polygenic mouse model for type 2 diabetes associated with fasting hyperglycaemia, glucose intolerance, hyperinsulinaemia, mild obesity and dyslipidaemia. Recently, we reported the susceptibility loci contributing to type 2 diabetes and related phenotypes in KK/Ta mice. In the present study, to identify susceptibility genes for type 2 diabetes and related disorders, GeneChip Expression Analysis was employed to survey the gene expression profile in the liver of KK/Ta and BALB/c mice. M-cadherin, a calciumdependent intercellular adhesion molecule, showed increased expression in the liver of KK/Ta mice, and sequence analysis revealed three missense mutations. The relationship between these polymorphisms and various phenotypes in 208 KK/Ta x (BALB/c x KK/Ta) F1 backcross mice was analysed. Statistical analysis revealed that M-cadherin exhibits linkage to levels of triglyceride and insulin in sera, glucose tolerance and body weight. Although it has been postulated that M-cadherin may be important for the regulation of morphogenesis of skeletal muscle cells, these results suggest that M-cadherin may influence hypertriglyceridaemia, glucose intolerance, hyperinsulinaemia and obesity in KK/Ta mice.


Subject(s)
Cadherins/genetics , Diabetes Mellitus, Experimental/genetics , Diabetes Mellitus, Type 2/genetics , Phenotype , Amino Acid Sequence , Animals , Cadherins/metabolism , Crosses, Genetic , Female , Gene Expression Profiling , Genetic Predisposition to Disease , Male , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Sequence Homology, Amino Acid
2.
J Toxicol Sci ; 26(3): 119-27, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11552295

ABSTRACT

The effect of chlormadinone acetate (CMA), a synthetic steroidal antiandrogen, on spontaneous benign prostatic hyperplasia (BPH) in dogs was investigated. Male beagle dogs (5-8 years old) were divided into four experimental group. Group 1 consisted of untreated controls. Groups 2 and 3 received CMA 0.03 and 0.1 mg/kg/day, p.o., respectively, for 6 months. In group 1, glandular hyperplasia of the prostate was clearly detected. The glandular epithelial cells showed uniformly intense nuclear staining for androgen receptor (AR). AR was also localized in the nuclei of the fibro-muscular stromal cells. In groups 2 and 3, CMA produced marked atrophy of the glandular epithelium. The interacinar fibro-muscular stroma was prominent. The nuclear staining for AR in both epithelial and stromal cells was remarkably decreased. In addition, a histopathological study showed that CMA medication for 6 months exerted no effect on the testes and adrenal glands or on immunoreactive positive cells to LH- and ACTH-antibody (pituitary LH- and ACTH-cells). Therefore, it is concluded that CMA (0.03 and 0.1 mg/kg) causes regression of spontaneous canine BPH without any histopathological effects on the testes, adrenal glands or pituitary LH- and ACTH-cells.


Subject(s)
Adrenal Glands/drug effects , Androgen Antagonists/adverse effects , Chlormadinone Acetate/adverse effects , Pituitary Gland/drug effects , Prostate/drug effects , Prostatic Hyperplasia/drug therapy , Testis/drug effects , Adrenal Glands/chemistry , Adrenal Glands/pathology , Adrenocorticotropic Hormone/analysis , Animals , Dogs , Fluorescent Antibody Technique, Indirect , Immunohistochemistry , Luteinizing Hormone/analysis , Male , Organ Size/drug effects , Pituitary Gland/chemistry , Pituitary Gland/pathology , Prostate/chemistry , Prostate/pathology , Receptors, Androgen/analysis , Testis/chemistry , Testis/pathology
3.
Toxicol Lett ; 121(2): 97-106, 2001 Apr 30.
Article in English | MEDLINE | ID: mdl-11325560

ABSTRACT

One of the major dose-limiting toxicities induced by antimicrotubule antitumor agents such as vinca alkaloids and taxanes is peripheral neuropathy. The neurotoxicity of TZT-1027 (a dolastatin 10 derivative antimicrotubule agent) was thus assessed using the animal models for antimicrotubule agent-induced neurotoxicity. Rabbits were intravenously given TZT-1027 or vincristine weekly for 5 weeks. In the mouse study, TZT-1027, vincristine or paclitaxel was intravenously given every 2 days and/or weekly. Despite the neuropathologic evidence such as myelinated axonal and fiber degeneration in the peripheral nerves and in the sensory tracts of the spinal cord following the treatment with vincristine or paclitaxel, no drug-induced alteration was observed in the TZT-1027 groups. Although there are reports that some other dolastatin derivatives with antimicrotubule activity showed no neurotoxic potential in humans, the present study represents the first demonstration in experimental animals that a dolastatin derivative has no, or at least a lower, neurotoxic potential compared to other antimicrotubule agents.


Subject(s)
Antineoplastic Agents/toxicity , Oligopeptides/toxicity , Peripheral Nerves/drug effects , Animals , Coloring Agents , Hematoxylin , Male , Mice , Microtubules/drug effects , Microtubules/pathology , Models, Animal , Osmium Tetroxide , Paclitaxel/toxicity , Peripheral Nerves/pathology , Rabbits , Sciatic Nerve/drug effects , Spinal Cord/drug effects , Tolonium Chloride , Vincristine/toxicity
4.
Carcinogenesis ; 22(3): 467-72, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11238188

ABSTRACT

The chemopreventive efficacy of lycopene and curcumin with regard to prostate carcinogenesis was investigated using 3,2'-dimethyl-4-aminobiphenol (DMAB)- and 2-amino-1-methylimidazo[4,5-b]pyridine (PhIP)-induced rat ventral prostate cancer models. Three 60 week experiments with male F344 rats were carried out. In the first DMAB was given for the first 20 weeks and lycopene or curcumin were administered concomitantly or subsequently at dietary doses of 15 and 500 p.p.m., respectively. In the second experiment lycopene and curcumin were given to rats pretreated with DMAB at doses of 5, 15 or 45 p.p.m. or 100 or 500 p.p.m. In the third PhIP was selected as an initiator for prostate carcinogenesis and administered for 20 weeks. Rats were then fed a diet containing lycopene at a dose of 45 p.p.m. or curcumin at a dose of 500 p.p.m. or both together. Chemopreventive effects of lycopene and curcumin on development of DMAB-induced ventral prostate carcinomas were observed only in the first experiment and no confirmation of inhibition potential was obtained in the following studies. Neither summational nor synergistic chemoprevention was evident. It is concluded from the present data that, overall, neither lycopene nor curcumin can consistently prevent rat prostate carcinogenesis.


Subject(s)
Anticarcinogenic Agents/pharmacology , Carotenoids/pharmacology , Curcumin/pharmacology , Prostatic Neoplasms/prevention & control , Aminobiphenyl Compounds/toxicity , Animals , Carcinogens/toxicity , Imidazoles/toxicity , Lycopene , Male , Prostatic Neoplasms/chemically induced , Rats , Rats, Inbred F344
5.
Tokai J Exp Clin Med ; 26(2): 71-5, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11806444

ABSTRACT

The effect of a synthetic steroidal antiandrogen, chlormadinone acetate (CMA), on spontaneous benign prostatic hyperplasia (BPH) in dogs was investigated. Male beagle dogs (5-8 years old) were divided into four experimental groups. Group 1 consisted of untreated controls. Groups 2 to 4 received CMA 0.03, 0.1, and 0.3 mg/kg/day, p.o., respectively, for 6 months. In group 1, glandular hyperplasia of the prostate was clearly detected. In groups 2 to 4, CMA produced marked atrophy of the glandular epithelium. The interacinar fibro-muscular stroma was prominent. To evaluate the frequency of apoptosis, we counted the positive cells stained by the nick end labeling method. In group 1, the apoptotic index was 0.76 +/- 0.03%. In groups 2 to 4, apoptotic index were 15.41 +/- 1.26%, 2.63 +/- 0.98% and 1.45 +/- 0.85%, respectively. Apoptotic cell death was mainly observed in the glandular may be epithelial cells. Based on our data, regression of BPH after treatment with CMA apoptotic cell death.


Subject(s)
Androgen Antagonists/pharmacology , Apoptosis/drug effects , Chlormadinone Acetate/pharmacology , Progesterone Congeners/pharmacology , Prostate/pathology , Prostatic Hyperplasia/pathology , Androgen Antagonists/therapeutic use , Animals , Atrophy , Chlormadinone Acetate/therapeutic use , Dogs , Male , Progesterone Congeners/therapeutic use , Prostatic Hyperplasia/drug therapy
6.
Neurotoxicology ; 21(4): 501-11, 2000 Aug.
Article in English | MEDLINE | ID: mdl-11022859

ABSTRACT

Vincristine is an effective chemotherapeutic agent for a variety of human neoplasms, but has dose-limiting neurotoxicity. Since laboratory rodents have proven to be refractive in such neurotoxicological studies, we conducted a neuropathological and behavioral assessment in rabbits treated with vincristine at doses known to be both chemotherapeutically effective and neurotoxic in humans. Rabbits (Kbl: NZW) were given vincristine intravenously at doses of 0 (saline), 200, 250 or 300 microg/kg once a week for 6 weeks, 500 microg/kg once a week for 3 weeks, or a single 500 microg/kg administration. Detailed periodic neurologic examination revealed ataxia in a few animals. Pathologically, axonal injury progressing to fiber degeneration was observed in sensory tracts such as the posterior spinocerebellar tract and posterior funiculus, and in peripheral nerves after treatment with vincristine. These alterations were observed even after a single dose of 500 microg/kg. In the group given weekly doses of 500 microg/kg, neuronal chromatolysis was also found in the spinal cord. These results suggest the rabbit is responsive to vincristine neurotoxicity producing a predominantly sensory neuropathy and confirming earlier studies.


Subject(s)
Antineoplastic Agents, Phytogenic/toxicity , Neurotoxicity Syndromes/pathology , Vincristine/toxicity , Animals , Behavior, Animal/drug effects , Brain/pathology , Ganglia, Spinal/pathology , Male , Nerve Fibers/pathology , Neurotoxicity Syndromes/psychology , Rabbits , Sciatic Nerve/pathology , Spinal Cord/pathology , Time Factors
7.
Tokai J Exp Clin Med ; 25(1): 7-10, 2000 Apr.
Article in English | MEDLINE | ID: mdl-11023049

ABSTRACT

The efficacy and clinical safety of chlormadinone acetate (CMA) in preventing estrus were assessed in queens on condition that CMA was subcutaneously implanted in siliastic rubber. Thirteen queens were divided into the following four groups according to dose of CMA-administered: group 1 (n = 3), control; group 2 (n = 3), 2.5 mg/kg; group 3 (n = 3), 5 mg/kg; group 4 (n = 4), 20 mg/kg. The implants were left in these queens for 12 months after implantation. All control animals showed signs of estrus during the experiment, with periods of anestrus of normal duration. In contrast, estrus was completely inhibited in the CMA-treated groups. Histopathologically, the uterus from group 4 had coiled branched glands with little secretion in the endometrium. Mammary glands from the CMA-treated groups showed mild lobular development with acinar proliferation and secretion. Sections through the other organs (pituitary gland, adrenal gland, ovary, and implant site) had no distinct or consistent changes that could be related to the CMA-treated. It was concluded, therefore, subcutaneous implantation of CMA could be the good drug-delivery system for reducing changes due to the antigonadotropic and glucocorticoid-like activities and serious condition in the uterine and mammary gland due to progestagenic activity.


Subject(s)
Chlormadinone Acetate/pharmacology , Estrus/drug effects , Ovary/pathology , Progesterone Congeners/pharmacology , Animals , Cats , Chlormadinone Acetate/analogs & derivatives , Estrus/physiology , Female , Injections, Subcutaneous , Ovary/drug effects , Progesterone Congeners/administration & dosage
8.
Tokai J Exp Clin Med ; 25(1): 11-4, 2000 Apr.
Article in English | MEDLINE | ID: mdl-11023050

ABSTRACT

The effect of synthetic steroidal antiandrogen, chlormadinone acetate (CMA), on spontaneous benign prostatic hyperplasia (BPH) in dogs was investigated. Male beagle dogs (5-8 years old) were divided into three experimental groups. Group 1 consisted of untreated controls. Groups 2 and 3 received CMA 0.03, and 0.1 mg/kg/day, p.o., respectively, for 6 months. In group 1, glandular hyperplasia of the prostate was clearly detected. In groups 2 and 3, CMA produced marked atrophy of the glandular epithelium. In addition, a histopathological study showed that CMA medication for 6 months exerted no effect on the testes and adrenals or on immunoreactive LH- and ACTH- cells of the anterior pituitary glands. Therefore, it is suggested that CMA (0.03 and 0.1 mg/kg) causes regression of spontaneous canine BPH without any histopathological effects on the testes, adrenals or anterior pituitary LH- and ACTH-cells.


Subject(s)
Androgen Antagonists/pharmacology , Chlormadinone Acetate/pharmacology , Prostatic Hyperplasia/drug therapy , Adrenal Glands/chemistry , Adrenal Glands/drug effects , Adrenal Glands/pathology , Adrenocorticotropic Hormone/analysis , Androgen Antagonists/administration & dosage , Animals , Chlormadinone Acetate/administration & dosage , Dogs , Luteinizing Hormone/analysis , Male , Organ Size , Pituitary Gland, Anterior/drug effects , Pituitary Gland, Anterior/pathology , Prostate/drug effects , Prostate/pathology , Prostatic Hyperplasia/pathology , Testis/drug effects , Testis/pathology
9.
J Toxicol Sci ; 25(3): 143-50, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10987120

ABSTRACT

The atrophic effect of a synthetic steroidal antiandrogen, chlormadinone acetate (CMA), on spontaneous benign prostatic hyperplasia (BPH) in dogs was investigated. Male beagle dogs (5-8 years old) were divided into four experimental groups. Group 1 consisted of untreated controls. Groups 2 to 4 received CMA 0.03, 0.1, and 0.3 mg/kg/day, p.o., respectively, for 6 months. In group 1, glandular hyperplasia of the prostate was clearly detected. The glandular epithelial cells showed uniformly intense nuclear staining for androgen receptor (AR). AR was also localized in the nuclei of the fibro-muscular stromal cells. Immunoreactivity of 5 alpha-reductase type I was positive in most glandular epithelial cells. No fibro-muscular stromal cells were stained. Immunolocalization of 5 alpha-reductase type II was clearly detected in the interacinar fibro-muscular stromal cells, but not in the glandular epithelial cells. In groups 2 to 4, CMA produced marked atrophy of the glandular epithelium. The interacinar fibro-muscular stroma was prominent. The nuclear staining for AR in both epithelial and stromal cells was remarkably decreased. Furthermore, the immunoreaction for 5 alpha-reductase type I in most glandular epithelial cells was negative or very weak. The immunoreaction of 5 alpha-reductase type II in the interacinar fibro-muscular stromal cells was negative or very weak. These results indicate that the uptake of testosterone and/or its androgenic effect on the prostate may be suppressed by CMA. The decreased AR-immunostaining may be explained by the decrease in the number of AR and/or antibody binding sites for AR. Therefore, the atrophy after treatment with CMA may be due to shrinkage of both glandular and stromal compartments in the prostate tissue.


Subject(s)
Androgen Antagonists/toxicity , Chlormadinone Acetate/toxicity , Prostate/pathology , Prostatic Hyperplasia/pathology , 3-Oxo-5-alpha-Steroid 4-Dehydrogenase/metabolism , Animals , Atrophy/chemically induced , Dogs , Immunohistochemistry , Isoenzymes/metabolism , Male , Organ Size/drug effects , Prostate/enzymology , Prostatic Hyperplasia/enzymology , Receptors, Androgen/metabolism
10.
Jpn J Cancer Res ; 91(8): 837-44, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10965026

ABSTRACT

TZT-1027, a dolastatin 10 derivative, is an antimicrotubule agent with potent antitumor activity both in vitro and in vivo. In this study, we performed biochemical and histopathological examinations, and evaluated TZT-1027-induced tumoral vascular collapse and tumor cell death in an advanced tumor model, murine colon 26 adenocarcinoma. In addition, we studied the effects of TZT-1027 on cultured human umbilical vein endothelial cells (HUVEC). Tolerable doses of TZT-1027 induced tumor-selective hemorrhage within 1 h. This hemorrhage occurred mainly in the peripheral area of the tumor mass. Measurements of tumoral hemoglobin content and dye permeation revealed that the hemorrhage occurred firstly and tumor blood flow stopped secondarily. The vascular damage was followed by continuous induction of apoptosis of the tumor cells, tumor tissue necrosis, and tumor regression. In cultured HUVEC, TZT-1027 induced marked cell contraction with membrane blebbing in 30 min. These cell changes were completely inhibited by K252a, a broad-spectrum inhibitor of protein kinases. These effects of TZT-1027 on both tumor vasculature and HUVEC were greater than those of vincristine. In conclusion, TZT-1027 quickly attacked the well-developed vascular system of advanced tumors by a putative protein kinase-dependent mechanism, and then blocked tumor blood flow. Therefore, TZT-1027 has both a conventional antitumor activity and a unique anti-tumoral vascular activity, making it a potentially powerful tool for clinical cancer therapy.


Subject(s)
Antineoplastic Agents/therapeutic use , Colonic Neoplasms/drug therapy , Microtubules/drug effects , Oligopeptides/therapeutic use , Animals , Antineoplastic Agents/pharmacology , Cell Survival/drug effects , Colonic Neoplasms/genetics , Colonic Neoplasms/pathology , Colonic Neoplasms/physiopathology , DNA Fragmentation/drug effects , Disease Models, Animal , Endothelium, Vascular/drug effects , Female , Hemoglobins/metabolism , Humans , Mice , Mice, Inbred BALB C , Neoplasm Transplantation , Neovascularization, Pathologic/drug therapy , Oligopeptides/pharmacology , Permeability , Tumor Cells, Cultured
11.
Endocr J ; 47(1): 13-20, 2000 Feb.
Article in English | MEDLINE | ID: mdl-10811288

ABSTRACT

To elucidate the effects of synthetic salmon calcitonin (sCT) on the cells in the rat pituitary gland, we histopathologically and immunohistochemically examined the early changes after 4 or 13 weeks treatment with sCT 120 IU/kg. Focal proliferative lesions of the anterior pituitary glands were consistently found after treatment with sCT for 13 weeks. Histologically, the cells with the focal proliferative lesions were classified into the following three groups: 1) enlarged basophilic cell focus, 2) vacuolated cell focus and 3) chromophobe cell focus. These focal proliferative lesions had positive staining only for the alpha-subunit and failed to show Pit-1 protein immunoreactivity. The sCT treatment also increased the thickness of the pars intermedia. Hypertrophy of the pars intermediate cells was characteristically seen. Furthermore, Pit-1 protein immunoreactivity was clearly detected in the nuclei of the hyperplastic pars intermediate cells. All pars intermediate cells were equally stained by alpha- or beta-MSH and beta-endorphin in both vehicle- and sCT-treatment. No difference was seen. These findings strongly suggest a very close relationship between Pit-1 protein immunoreactivity and cellular proliferation induced by sCT.


Subject(s)
Calcitonin/pharmacology , DNA-Binding Proteins/metabolism , Pituitary Gland, Anterior/metabolism , Pituitary Gland, Anterior/pathology , Pituitary Gland/drug effects , Transcription Factors/metabolism , Animals , Hyperplasia , Immunohistochemistry , Male , Rats , Rats, Sprague-Dawley , Salmon , Transcription Factor Pit-1
12.
Biofactors ; 13(1-4): 89-94, 2000.
Article in English | MEDLINE | ID: mdl-11237205

ABSTRACT

Various natural carotenoids were proven to have anticarcinogenic activity. Epidemiological investigations have shown that cancer risk is inversely related to the consumption of green and yellow vegetables and fruits. Since beta-carotene is present in abundance in these vegetables and fruits, it has been investigated extensively as possible cancer preventive agent. However, various carotenoids which co-exist with beta-carotene in vegetables and fruits also have anti-carcinogenic activity. And some of them, such as alpha-carotene, showed higher potency than beta-carotene to suppress experimental carcinogenesis. Thus, we have carried out more extensive studies on cancer preventive activities of natural carotenoids in foods; i.e., lutein, lycopene, zeaxanthin and beta-cryptoxanthin. Analysis of the action mechanism of these natural carotenoids is now in progress, and some interesting results have already obtained; for example, beta-cryptoxanthin was suggested to stimulate the expression of RB gene, an anti-oncogene, and p73 gene, which is known as one of the p53-related genes. Based on these results, multi-carotenoids (mixture of natural carotenoids) seems to be of interest to evaluate its usefulness for practice in human cancer prevention.


Subject(s)
Anticarcinogenic Agents/pharmacology , Carotenoids/pharmacology , Colonic Neoplasms/prevention & control , Skin Neoplasms/prevention & control , beta Carotene/analogs & derivatives , 9,10-Dimethyl-1,2-benzanthracene , Animals , Colonic Neoplasms/chemically induced , Cryptoxanthins , Disease Models, Animal , Fruit , Humans , Lutein/pharmacology , Lycopene , Methylnitrosourea , Mice , Rats , Rats, Inbred F344 , Skin Neoplasms/chemically induced , Tetradecanoylphorbol Acetate , Vegetables , Xanthophylls , Zeaxanthins , beta Carotene/pharmacology
13.
Tokai J Exp Clin Med ; 25(3): 87-91, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11368213

ABSTRACT

The histopathological changes related to chlormadinone acetate (CMA) implantation were examined using female beagle dogs given 10mg/kg for four years. All control animals showed sign of estrus during the experiment, with periods of anestrus of normal duration. In contrast, estrus was completely inhibited in the CMA-implanted animals. Histopathologically, uterine sections from the CMA-implanted animals showed cystic glandular hyperplasia, but no histologic evidence of endometritis, myometritis, and pyometra was found. In the ovaries of the CMA-implanted animals, developing ovarian follicles were observed but no mature follicles were noted in addition to an absence of corpus luteum. No remarkable changes were observed in the liver, adrenal, mammary gland, gallbladder and implanted site. Furthermore, the intensity of staining and number and size of ACTH-and LH-positive cells in the pituitary sections of CMA-implanted animals were not different from control animals. It was concluded, therefore, that subcutaneous implantation of CMA is a potential drug-delivery system for reducing changes due to antigonadotropic and glucocorticoid-like activities and characteristic histopathological changes in the uterus due to progestagenic activity.


Subject(s)
Chlormadinone Acetate/administration & dosage , Contraceptive Agents, Female/administration & dosage , Estrus/drug effects , Ovary/drug effects , Uterus/drug effects , Animals , Chlormadinone Acetate/pharmacology , Contraceptive Agents, Female/pharmacology , Dogs , Drug Implants , Female , Gallbladder/drug effects , Gallbladder/pathology , Mammary Glands, Animal/drug effects , Mammary Glands, Animal/pathology , Ovary/pathology , Uterus/pathology
14.
J Toxicol Sci ; 24(3): 209-16, 1999 Aug.
Article in English | MEDLINE | ID: mdl-10478335

ABSTRACT

In order to confirm the relationship between glutathione-peroxidase (GSH-PO) localization and biological testosterone action in the rat ventral prostate, immunocytochemical localization of GSH-PO in glandular epithelial cells of the rat ventral prostate was investigated. In the untreated group, GSH-PO was predominantly demonstrated in glandular epithelial cells of the ventral prostate. Intracellular localization of GSH-PO in the glandular epithelial cells was mainly observed in cytoplasmic matrix near the rough endoplasmic reticulum and was occasionally noted as a small granular structure (GSH-PO-positive granule) at the supranuclear region. In a castrated animal, the intensity of GSH-PO staining in the glandular epithelial cells was remarkably decreased. By testosterone administration to the castrated animal, GSH-PO was clearly detected in the glandular epithelial cells. Intracellular localization of GSH-PO was mainly observed in cytoplasmic matrix and the number of GSH-PO-positive granules increased remarkably. These findings suggest that immunostainable GSH-PO in the glandular epithelial cells of the rat ventral prostate is testosterone-dependent, and that its staining pattern is a useful marker for biological testosterone action.


Subject(s)
Glutathione Peroxidase/metabolism , Prostate/drug effects , Testosterone/pharmacology , Animals , Epithelial Cells/drug effects , Epithelial Cells/enzymology , Epithelial Cells/ultrastructure , Immunoenzyme Techniques , Male , Microscopy, Electron , Orchiectomy , Prostate/cytology , Prostate/enzymology , Rats , Rats, Sprague-Dawley
15.
Anticancer Res ; 19(5A): 3663-4, 1999.
Article in English | MEDLINE | ID: mdl-10625935

ABSTRACT

It has been reported that myo-inositol can inhibit carcinogenesis in various organs, such as the mammary gland, colon and lung. In the present study, at first, inhibitory effects of myo-inositol on lung carcinogenesis were confirmed. Then, the influence of myo-inositol on liver carcinogenesis in mice was investigated. In C3H/He male mice, the rate of spontaneous liver carcinogenesis is known to be high. Using this experimental model, the effects of oral administration of myo-inositol (added into the drinking water at the concentration of 1%) were assessed. Significant suppression of liver carcinogenesis was observed in mice treated with myo-inositol for 40 weeks. In the control group without myo-inositol administration, 88% of the animals developed liver tumors, whereas in the myo-inositol-supplemented group, the incidence of liver tumors was 38% (p < 0.05). The average number of liver tumors per mouse was also decreased significantly by myo-inositol treatment; from 7.8 in the control group to 0.8 in the myo-inositol-supplemented group (p < 0.01). Thus, myo-inositol may be useful for cancer chemoprevention in the liver, as well as the lung.


Subject(s)
Anticarcinogenic Agents/therapeutic use , Inositol/therapeutic use , Liver Neoplasms, Experimental/prevention & control , Lung Neoplasms/prevention & control , Administration, Oral , Animals , Male , Mice , Mice, Inbred C3H
16.
J Toxicol Sci ; 24(5): 415-20, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10656163

ABSTRACT

In order to confirm the relationship between sex hormone administration and glutathione-peroxidase (GSH-PO) in the rat ventral prostate, the levels of GSH-PO mRNA, GSH-PO activity, and lipid peroxide (TBA) value in the ventral prostate were investigated. Male Crj:CD(SD)IGS rats were divided into six experimental groups. Group 1 consisted of intact controls. In group 2, rats were sacrificed two days after castration. In groups 3 and 4, rats were subcutaneously administered 1 mg/animal of testosterone daily for three or seven days after two days of castration, respectively. In groups 5 and 6, rats were subcutaneously administered 1 mg/animal of testosterone plus 0.01 mg/animal of 17 beta-estradiol (E2) daily for three or seven days after two days of castration, respectively. GSH-PO activity of the ventral prostate homogenate for testosterone or testosterone plus E2 administration to the castrated rat was increased and the TBA value was remarkably decreased. The prostatic GSH-PO mRNA level was diminished in the castrated rat ventral prostate, but was increased by testosterone or testosterone plus E2 administration. In particular, the GSH-PO mRNA level of testosterone plus E2-treated animals was higher than that of testosterone-treated animals. These findings strongly suggest that expression of GSH-PO in the rat ventral prostate is considered to be testosterone- or E2-dependent. Furthermore, it is suggested that the transcription of prostatic GSH-PO mRNA was regulated by testosterone or E2 and de novo synthesis of GSH-PO would thus be regulated at transcription level by testosterone or E2.


Subject(s)
Estradiol/administration & dosage , Glutathione Peroxidase/metabolism , Prostate/enzymology , Testosterone/administration & dosage , Animals , Glutathione Peroxidase/genetics , Male , RNA, Messenger/analysis , Rats
17.
Tokai J Exp Clin Med ; 24(2): 77-83, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10641996

ABSTRACT

To investigated spontaneous benign prostatic hyperplasia (BPH) in dog the effect of a synthetic steroidal antiandrogen, chlormadinone acetate (CMA) was studied. Old male beagle dogs (5-8 years old) were divided into following experimental groups: group 1 consisted of BPH controls; group 2 received CMA 0.3mg/kg/day p.o., for 6 months. In group 1 animals, glandular hyperplasia of the prostate was clearly detected. The glandular epithelial cells showed uniformly intense immunostaining for nuclear androgen receptors (AR). AR was also localized in the nuclei of the fibro-muscular cells. Immunoreactivity of 5alpha-reductase type I was positive in most glandular epithelial cells. The staining was positive in the cytoplasm but not in the nuclei. No fibro-muscular cells were stained. In contrast, CMA produced marked atrophy of the glandular epithelium. The interacinar fibro-muscular stroma was prominent. Furthermore, immunostaining of nuclear AR of both epithelial and stroma cells was remarkably decreased. The intensity of staining for 5alpha-reductase type I in most glandular epithelial cells also decreased. Interestingly, some basal cells exhibited positive staining for 5alpha-reductase type I. These results indicate that the uptake of testosterone and/or its androgenic effect on the prostate may be suppressed by CMA. We further speculate that the basal cells produce sufficient dihydrotestosterone to maintain themselves even in the presence of low testosterone levels.


Subject(s)
Androgen Antagonists/pharmacology , Androgens/metabolism , Chlormadinone Acetate/pharmacology , Progesterone Congeners/pharmacology , Prostatic Hyperplasia/drug therapy , Prostatic Hyperplasia/metabolism , Receptors, Androgen/metabolism , Androgen Antagonists/therapeutic use , Animals , Chlormadinone Acetate/therapeutic use , Dogs , Immunohistochemistry , Male , Progesterone Congeners/therapeutic use , Prostatic Hyperplasia/pathology
18.
Carcinogenesis ; 19(1): 81-5, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9472697

ABSTRACT

The present study was carried out to examine the chemopreventive effects of carotenoids such as fucoxanthin, lycopene and lutein as well as curcumin and its derivative, tetrahydrocurcumin (THC), on development of putative preneoplastic aberrant crypt foci (ACF) in colons of mice initiated with 1,2-dimethylhydrazine dihydrochloride (DMH). Influence on proliferation of colonic crypt epithelial cells was also assessed in terms of 5-bromo-2'-deoxyuridine (BrdU) incorporation. Five-week-old B6C3F1 male mice were divided into three groups, groups 1 and 2 being given DMH (20 mg/kg body wt, s.c.) twice a week for 3 weeks. Animals of group 1 were then treated with one of the test compounds, lycopene (0.005% and 0.0025%) or fucoxanthin (0.01%) in the drinking water and lutein (0.05%), curcumin (0.5%) or THC (0.5% and 0.2%) in the diet from weeks 5-12. Group 2 served as a carcinogen alone control and group 3 mice were given test compounds alone. All animals were killed at week 12. Numbers of ACF/mouse in the group 1 treated with fucoxanthin (47.1 +/- 13.7), lutein (42.6 +/- 19.6) or 0.5% THC (46.6 +/- 17.7) were significantly decreased as compared to the control group 2 value (63.3 +/- 19.4) (P < 0.01). Numbers of aberrant crypts (ACs)/mouse were also significantly lower after treatment with lutein (79.9 +/- 34.7) or 0.5% THC (81.8 +/- 32.5) than in the control group (115.1 +/- 37.1) (P < 0.01). BrdU labeling indices (LI) in mice treated with lutein and 0.5% THC were significantly decreased in both upper and lower half compartments of colonic crypts as compared to the controls (P < 0.05 and 0.01, respectively), especially the upper half data corresponding to reduction of ACs/mouse. The results thus suggest that fucoxanthin, lutein, and THC may have potential as chemopreventive agents against colon carcinogenesis.


Subject(s)
1,2-Dimethylhydrazine , Anticarcinogenic Agents/therapeutic use , Carcinogens , Carotenoids/therapeutic use , Colon/drug effects , Colonic Neoplasms/prevention & control , Curcumin/therapeutic use , Intestinal Mucosa/drug effects , Animals , Cell Division/drug effects , Colon/cytology , Colon/pathology , Colonic Neoplasms/chemically induced , Curcumin/analogs & derivatives , Intestinal Mucosa/cytology , Intestinal Mucosa/pathology , Male , Mice , Mice, Inbred Strains
19.
Tokai J Exp Clin Med ; 23(5): 209-12, 1998 Nov.
Article in English | MEDLINE | ID: mdl-10418722

ABSTRACT

The effect of a synthetic steroidal anti-androgen, chlormadinone acetate (CMA), on spontaneous benign prostatic hyperplasia (BPH) in the dog was investigated. Old male beagle dogs (5 to 8 years old) were divided into the following experimental groups: group 1 consisting of BPH controls, and group 2 which received CMA of 0.3 mg/kg/day orally for 6 months. In group 1, glandular hyperplasia of the prostate was clearly observed. The glandular epithelial cells showed uniformly intense nuclear immunostaining for androgen receptor (AR). In contrast, CMA produced marked atrophy of the glandular epithelium. The interacinar fibromuscular stroma was prominent. Furthermore, nuclear immunostaining for AR in both epithelial and stroma cells was remarkably decreased. These results indicate that the uptake of testosterone and/or its androgenic effect on the prostate may be suppressed by CMA. The decreased AR-immunostaining may be explained by the decrease in the number of AR and/or antibody binding sites for AR.


Subject(s)
Androgen Antagonists/pharmacology , Chlormadinone Acetate/pharmacology , Prostate/chemistry , Prostatic Hyperplasia/metabolism , Receptors, Androgen/analysis , Androgen Antagonists/administration & dosage , Animals , Chlormadinone Acetate/administration & dosage , Dogs , Male , Organ Size , Prostate/drug effects , Prostate/ultrastructure , Prostatic Hyperplasia/pathology
20.
Tokai J Exp Clin Med ; 23(5): 245-8, 1998 Nov.
Article in English | MEDLINE | ID: mdl-10418729

ABSTRACT

Ultrastructural changes in canine prostates after treatment with chlormadinone acetate (CMA) were investigated. Old male beagle dogs (5-8 years old ) were divided into two experimental groups; group 1 consisted of benign prostatic hyperplasia (BPH) controls, and group 2 received 0.3 mg/kg/day CMA orally for 6 months. In group 1 animals, the most striking ultrastructural changes were detected in the rough endoplasmic reticulum (rER) and Golgi complexes. The secretory granules were lined up along the apical plasma membrane, and exocytosis was frequently seen. In group 2 animals, the cytoplasm was electron-lucent and contained relatively few, poorly developed organelles. The rER was sparse and consisted of a few scattered, short profiles studded with ribosomes. The Golgi complexes were inconspicuous. The secretory granules were markedly decreased in both number and size. Furthermore, mitochondrial degeneration such as swollen or disappeared mitochondrial cristae or decreased electron density of the matrix were frequently seen in the smooth muscle cells. Based on our data, atrophy after treatment with CMA may be due to shrinkage of both glandular and stromal compartments in the prostate tissue.


Subject(s)
Chlormadinone Acetate/pharmacology , Progesterone Congeners/pharmacology , Prostate/ultrastructure , Prostatic Hyperplasia/pathology , Animals , Dogs , Male , Prostate/drug effects , Prostate/pathology
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