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S Sugie

Publications and source records attributed to S Sugie.

At least 19 recordsLinked to original sources

Toxicity and tumorigenicity of purpurin, a natural hydroxanthraquinone in rats: induction of bladder neoplasms.

Chronic toxicity and tumorigenicity of purpurin, a natural hydroxyanthraquinone, was examined in two groups of male F344 rats. One group was given a basal diet mixed with purpurin at a concentration of 1% throughout the experiment (520 days). Another group was kept on the basal diet without purpurin during the experiment. Almost all animals given purpurin developed conspicuous changes of kidney resembling 'progressive chronic nephropathies', the severity and frequency of which were much stronger than in controls. In rats with purpurin treatment, marked hyperplasia of pelvic epithelium was frequently seen and several rats developed urinary bladder tumors (papilloma and carcinoma). Prominent crystallization in the renal pelvis and urinary bladder seems to be initially related to the toxic effects of this hydroxanthraquinone on the renal tubules and with the occurrence of epithelial hyperplasia and neoplasms.

Animals

Chemopreventive effects of taurine on diethylnitrosamine and phenobarbital-induced hepatocarcinogenesis in male F344 rats.

Modifying effects of taurine, a naturally occurring organosulfur compound, on diethylnitrosamine (DEN) and phenobarbital (PB)-induced hepatocarcinogenesis were examined in rats. Male F344 rats, 5 weeks old, were divided into 8 groups. Rats of groups 1 through 5 were given i.p. injections of DEN (100 mg/kg body weight) once a week for 3 weeks from one week after the start of the experiment. Of them, animals of group 2 received taurine mixed in a basal diet at a concentration of 2000 ppm for the initial 4 weeks, and those of groups 3 and 5 were given the agent starting 4 weeks after the beginning of the experiment until the end (24 weeks). Rats in groups 1, 4, 7 and 8 were kept on the basal diet throughout the experiment (24 weeks). Group 6 was given taurine throughout the experiment and group 8 was treated as a vehicle control. Animals of groups 1,2, 3 and 7 received PB in drinking water at a dose of 500 ppm from one week after the end of carcinogen or vehicle treatment. Liver neoplasms were recognized only in DEN-treated groups. The incidence and average number of liver neoplasms of group 3 were significantly lower than those of group 1. The number of glutathione S-transferase placental form (GST-P)-positive foci of group 2 or 3 was significantly smaller than that of group 1 (P < 0.01 or P < 0.005). The average and unit areas of GST-P-positive foci in groups 2 and 3 were also significantly smaller than those in group 1 (P < 0.005 and P < 0.0001 and P < 0.0001, respectively). In this study, the level of ornithine decarboxylase activity in non-neoplastic liver tissue was reduced by taurine treatment in both the initiation and postinitiation phases. These results suggest that taurine could be a chemopreventive agent for liver neoplasia.

Animals

Effect of fish oil on the development of AOM-induced glutathione S-transferase placental form positive hepatocellular foci in male F344 rats.

Omega-3 fatty acids, which are contained in fish oils and certain vegetable oils in contrast to corn oil or safflower oil rich in omega-6 fatty acids (linoteic acid), have been reported to reduce the carcinogenesis in several organs. In this study, the modifying effect of menhaden fish oil was investigated on the occurrence of azoxymethane (AOM)-induced glutathione S-transferase placental form (GST-P) positive hepatocellular foci, recognized preneoplastic lesions in the liver, in male F344 rats. Starting at five weeks of age, groups of animals were fed ad libitum a semipurified diet containing 5% corn oil (low fat). At seven weeks of age, all animals except the vehicle-treated groups were injected subcutaneously with AOM (15 mg/kg body wt, 1x/wk for 2 wks). Four days after the second injection, groups of animals were fed the diets containing 4% menhaden oil + 1% corn oil (low fish oil diet), 22.5% menhaden oil + 1% corn oil (high fish oil diet), and 5% corn oil. Thirty-four weeks after AOM injections, all animals were necropsied. Livers were sectioned and performed immunohistochemical staining of GST-P for quantitative analysis of enzyme altered foci of the liver. The results demonstrate that the density and the unit area of AOM-induced enzyme altered foci in the liver were significantly lower in the high fish oil group (0.60 +/- 0.08/cm2, 3.0 +/- 0.4 x 10(-4)) than in the 5% corn oil group (2.71 +/- 0.33/cm2, 16.6 +/- 2.6 x 10(-4)) and the low fish oil group (1.66 +/- 0.33/cm2, 11.1 +/- 1.9 x 10(-4)).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Alterations of nuclear pores in preneoplastic and neoplastic rat liver lesions induced by 2-acetylaminofluorene.

The nuclear pore density and area were measured on freeze-fractured nuclei of ACI/N rat liver altered foci, adenomas and carcinomas induced by 2-acetylaminofluorene, and compared with those of normal hepatocytes. The pore density of nuclei from these preneoplastic and neoplastic lesions was significantly higher than that of hepatocytes, but there was no difference between lesions. The area of nuclear pores of the focus cells did not differ from normal hepatocytes, whereas the areas of pores of adenoma and carcinoma cells were increased. Moreover, the nuclear pore area of carcinomas was significantly greater than that of adenomas. These results suggest that some changes may occur in nuclear pores in the progress of tumorigenesis.

2-Acetylaminofluorene

Promoting and synergistic effects of chrysazin on 1,2-dimethylhydrazine-induced carcinogenesis in male ICR/CD-1 mice.

The modifying effects of chrysazin on 1,2-dimethylhydrazine (DMH)-induced colon and liver carcinogenesis were examined in male ICR/CD-1 mice. Starting at 6 weeks of age, mice were divided into four groups, two of which were treated with s.c. injections of DMH (20 mg/kg body wt) once a week for 12 weeks. A week after the final injection of DMH, one group was kept on the basal diet throughout the study (group I), and the other group was fed the diet containing chrysazin (mixed in basal diet at 0.2% concentration) alone for 42 weeks (group II). The other two groups were injected with normal saline and given the diet containing 0.2% chrysazin for 42 weeks (group III), or the basal diet during the experiment (group IV). The incidence and multiplicity of colon tumors of group II were significantly greater than those of group I (P < 0.05, P < 0.01). The incidence and multiplicity of the hepatocellular neoplasms of group II were larger than those of group I (P < 0.002, P < 0.02 respectively). In group III, colon tumors were not found, though a few liver neoplasms and severe inflammatory lesions of the colon were observed. The activity of ornithine decarboxylase of the colonic mucosa in mice exposed to chrysazin was stronger than that of animals without chrysazin. The results suggest that the promoting effect of chrysazin is probably related to an increase of cell proliferation in the target organ. A synergistic effect of DMH with chrysazin was also observed in liver tumorigenesis.

1,2-Dimethylhydrazine

Inhibitory effects of benzyl thiocyanate and benzyl isothiocyanate on methylazoxymethanol acetate-induced intestinal carcinogenesis in rats.

The effects of two aromatic thiocyanates, benzyl thiocyanate (BTC) and benzyl isothiocyanate (BITC), on methylazoxymethanol (MAM) acetate-induced intestinal carcinogenesis were examined using female ACI/N rats. Starting at 5 weeks of age, animals were fed diets containing 100 or 400 p.p.m. BTC, 400 p.p.m. BITC or a control diet. At 6 weeks of age, all animals were treated with i.p. injections of MAM acetate (25 mg/kg body wt, once weekly for 3 weeks) or saline. Animals fed experimental diets were changed to the control diet from a week after the last carcinogen treatment. Three groups of animals fed the control diet were switched to 100 p.p.m. BTC, 400 p.p.m. BTC or 400 p.p.m. BITC diet from a week after carcinogen treatment. Animals given the high-dose BTC diet at the initiation and the post-initiation phase showed smaller incidence (5% and 17%) and multiplicity (0.05 +/- 0.21 and 0.17 +/- 0.37) of tumours in small intestine compared with those of rats exposed to the carcinogen alone (61% and 1.06 +/- 1.18). The incidence and multiplicity of tumors in small intestine (21% and 0.32 +/- 0.73) and the incidence of colon tumors of rats given BITC in the initiation phase (47%) were significantly lower than those of animals treated with carcinogen alone (61%, 1.06 +/- 1.18 and 83%). Bromodeoxyuridine labeling indices of the intestinal mucosal cells were measured. The labeling indices were reduced by BTC and BITC exposure at initiation phase in both small intestine and colon. The results of measurement of labeling indices correlated with the decreased tumor incidence and multiplicity in the intestine. These data suggest that BTC and BITC could be promising chemopreventive agents for human intestinal neoplasia.

Animals

Effect of restricted caloric intake on the development of the azoxymethane-induced glutathione S-transferase placental form positive hepatocellular foci in male F344 rats.

The modifying effect of 30% caloric restriction on the occurrence of azoxymethane (AOM)-induced glutathione S-transferase placental form (GST-P) positive hepatocellular foci was investigated in male F344 rats. Starting at 5 weeks of age, groups of animals were fed ad libitum a high-fat (23.5%) semipurified diet. At 7 weeks of age, all animals except the vehicle-treated groups were s.c. injected with AOM (15 mg/kg body wt., once weekly for 2 weeks). Four days after the second injection, groups of animals were continued on high-fat diet and fed ad libitum (ad libitum group) whereas other groups were restricted to 70% of total calories (calorie-restricted group) consumed by the ad libitum group, but received the same amounts of fiber, vitamins and minerals. Thirty-two weeks after AOM injections, all animals were necropsied and livers were sectioned and stained for GST-P by a immunohistochemical technique for quantitative analysis of enzyme altered foci of the liver. Comparing AOM treated groups. The density and the unit area of enzyme altered foci were significantly lower in the calorie-restricted group (3.84 +/- 1.55/cm2, 7.96 +/- 5.43%) than in the ad libitum group (10.14 +/- 3.62/cm2, 28.11 +/- 12.33%). The size of foci was also reduced in the calorie-restricted group (17.15 x 10(-3) mm2 vs. 32.36 x 10(-3) mm2). The incidence and density of hepatocellular foci in rats fed calorie restricted diet were significantly lower than those in rats fed ad libitum, comparing vehicle-treated groups. These results indicate that calorie restriction inhibited the occurrence of both of spontaneous and AOM induced GST-P positive foci in rats.

Animals

Effect of varying proportions of dietary menhaden and corn oil on experimental rat mammary tumor promotion.

Dose-related effects of long-chain highly unsaturated n-3 fatty acids on the development of N-nitrosomethylurea (NMU)-induced rat mammary tumors were assessed in female F344 rats. Four test groups (36 rats/group) were fed the following high-fat (HF) diets (23% fat, w/w): Group 1, 18% menhaden oil (MO) and 5% corn oil (CO); Group 2, 11% MO and 11.8% CO; Group 3, 5% MO and 18% CO; Group 4, CO alone. A fifth group, serving as an internal control, was fed a low-fat diet containing 5% CO alone. Experimental diets were begun after initiation with NMU, and the experiment was terminated 31 wk later. Total tumor numbers in the five groups were 28, 16, 32, 26 and 11, respectively, indicating that the promotion phase of NMU-induced carcinogenesis was significantly suppressed only when equal parts of CO and MO (Group 2) were fed or when CO alone was fed at 5% (w/w). At high (Group 1) or low (Group 3) levels of MO, tumor numbers were indistinguishable from the HF CO group (Group 4). The same pattern was observed when assessed in terms of cumulative tumor incidence and multiplicity. However, when expressed in terms of final tumor incidence, dietary MO did not suppress tumor promotion in a statistically significant fashion at any concentration. Animals fed MO gained weight at the same rate as those fed CO, indicating that the presence of MO in the diet did not result in food avoidance behavior. Measurement of total serum cholesterol indicated an inverse trend with respect to the MO content of the diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenocarcinoma

Inhibitory effect of the non-steroidal anti-inflammatory drugs, indomethacin and piroxicam on 2-acetylaminofluorene-induced hepatocarcinogenesis in male ACI/N rats.

The modifying effects of the non-steroidal anti-inflammatory drugs, indomethacin (IMC) and piroxicam (PC) on hepatocarcinogenesis induced by 2-acetylaminofluorene (AAF) were investigated in male ACI/N rats. Rats were divided into 6 groups: group 1 was fed a diet containing 200 ppm AAF for 16 weeks, starting at 6 weeks of age; group 2 was fed an AAF together with 130 ppm PC-containing diet; group 3 received an AAF diet and IMC (10 ppm) in their drinking water; group 4 was fed a PC diet alone; group 5 was given IMC alone; and group 6 served as controls. The PC diet, or the drinking water containing IMC, was given to the rats starting at 5 weeks of age until 1 week after the carcinogen exposure. At termination of the experiment (week 36), the incidences of iron-excluding altered liver cell foci (24.2 +/- 5.2/cm2) and liver cell tumors (1/10, 10%), and the tumor multiplicity (0.10/rat) in rats of group 2 were significantly smaller than those of group 1 (foci incidence, 42.6 +/- 6.7/cm2; tumor incidence, 10/10, 100%; and multiplicity, 4.00/rat) (P < 0.05). Similarly, the incidence of iron-excluding hepatocellular foci (27.4 < 1.2/cm2) and liver cell tumors (1/10, 10%) and the tumor multiplicity (0.10/rat) in rats of group 3 were significantly lower than those of group 1 (P < 0.05). There were no liver cell lesions (foci and neoplasms) in rats of groups 4, 5 and 6. Thus, PC and IMC inhibited the hepatocarcinogenesis induced by AAF when administered concurrently with the carcinogen and the results may indicate possible involvement of altered arachidonic metabolism in the initiation phase of AAF-induced liver carcinogenesis.

2-Acetylaminofluorene

Modifying effects of benzyl isothiocyanate and benzyl thiocyanate on DNA synthesis in primary cultures of rat hepatocytes.

The effects of benzyl isothiocyanate (BITC) and benzyl thiocyanate (BTC) on two types of DNA synthesis were examined in hepatocyte primary cultures (HPC). Male F344 rats were fed BITC- or BTC-containing diets at a concentration of 400 p.p.m. Using hepatocytes isolated from these rats, DNA repair was measured by unscheduled DNA synthesis (UDS) for some genotoxic carcinogens, e.g. 2-acetylaminofluorene (AAF), methylazoxymethanol (MAM) acetate, 9,10-dimethyl-1,2-benzanthracene (DMBA) and diethylnitrosamine (DEN), and compared with that in the hepatocytes from rats without BITC or BTC treatment. Replicative DNA synthesis (RDS) was also evaluated in the hepatocytes of rats with or without thiocyanate treatment. Both BITC and BTC reduced UDS elicited by these carcinogens. The level of RDS in the hepatocytes of rats exposed to BITC or BTC was markedly lower than in the cells of rats without BITC or BTC exposure. These results indicate that in vivo exposure to BITC and BTC suppressed carcinogen-induced genotoxicity and cell proliferative activity and suggest that this assay may prove useful in detecting chemopreventive agents for cancer and in investigating the properties of carcinogenesis modifiers.

Animals

Inhibitory effects of benzyl isothiocyanate and benzyl thiocyanate on diethylnitrosamine-induced hepatocarcinogenesis in rats.

The effects of two aromatic thiocyanates, benzyl isothiocyanate (BITC) and benzyl thiocyanate (BTC), on diethylnitrosamine (DEN)-induced hepatocarcinogenesis were examined in rats. A total of 108 male ACI/N rats, 5 weeks old, were divided into 6 groups (18 rats in each). Group 1 was given a single i.p. injection of DEN (200 mg/kg body weight) one week after the start of the experiment and then kept on the basal diet until the end of the experiment (1 year). Groups 2 and 3 were treated with DEN and received dietary BITC (100 ppm) or BTC (100 ppm), respectively, throughout the experimental duration. Groups 4 and 5 were not given the carcinogen and were fed the diet containing BITC or BTC, respectively. Group 6 was kept on the basal diet alone and served as a control. Liver neoplasms were seen in Groups 1, 2 and 3. Incidence and average number of liver neoplasms in Group 2 were significantly smaller than in Group 1 (P < 0.0005 and P < 0.001, respectively). The incidence of liver neoplasms in Group 3 was slightly lower than in Group 1, although the difference was not statistically significant. The numbers of glutathione S-transferase placental form (GST-P)-positive foci in Group 2 and gamma-glutamyltranspeptidase (GGT)-positive foci in Groups 2 and 3 were significantly smaller than those in Group 1 (P < 0.001). The average and unit areas of GST-P- or GGT-positive foci in Group 2 or 3 were also significantly smaller than those in Group 1 (P < 0.05). These results suggest that BITC and BTC are chemopreventive agents for DEN-induced liver tumorigenesis.

Animals

Synergistic effect of radiation on colon carcinogenesis induced by methylazoxymethanol acetate in ACI/N rats.

The effect on colon and liver carcinogenicity in rats of a single X-irradiation exposure given either before or after methylazoxymethanol (MAM) acetate was studied in ACI/N rats of both sexes. A single dose of X-irradiation (3 Gy) was administered either 3 months before or after three weekly s.c. injections of MAM acetate (25 mg/kg body weight). At 365 days after the start, the incidence and multiplicity of MAM acetate-induced intestinal tumors were enhanced by X-irradiation either prior to or after the MAM acetate treatment. In addition, X-irradiation before MAM acetate increased the incidence of hepatocellular foci in either sex. In females, X-irradiation either before or after MAM acetate exposure decreased intestinal tumorigenesis. These findings suggest an apparent synergism of these agents in intestinal carcinogenesis of male rats.

Animals

Inhibitory effect of 5-hydroxy-4-(2-phenyl-(E)-ethenyl)-2(5H)-furanone, a novel synthesized retinoid, on azoxymethane-induced intestinal carcinogenesis in rats.

Modifying effects of 5-hydroxy-4-(2-phenyl-(E)-ethenyl)-2(5H)-furanone, a novel synthesized retinoid (KYN-54), on intestinal carcinogenesis were examined in a rat model using azoxymethane (AOM). A total of ninety male F344 rats, 6 weeks old, were divided into 4 groups. Group 1 (20 rats) was fed a diet containing KYN-54 at a concentration of 0.02% for 3 weeks, during which time 2 s.c. injections of azoxymethane (15 mg/kg) were applied and then kept on a basal diet until the end of the experiment (1 year). Group 2 (30 rats) was given azoxymethane as in group 1 and fed the basal diet throughout, without synthetic retinoid exposure. Group 3 (20 rats) was administered KYN-54 at the commencement of the experiment, but not given the carcinogen. Group 4 (20 rats) received a basal diet alone throughout the experiment and served as a control. Intestinal tumors were seen in groups 1 and 2, their incidence and average number in group 1 (74%, 1.07 +/- 0.87) being significantly less than in group 2 (39%, 0.56 +/- 0.78) (P < 0.02 and P < 0.05, respectively). These results suggest that the synthetic retinoid might be a promising chemopreventive agent for intestinal neoplasia.

4-Butyrolactone

A rare case of serous cystadenocarcinoma of the pancreas.

Serous cystadenocarcinoma of the pancreas, a rare disease, developed in a 63-year-old Japanese woman. Pathologic examinations of the pancreatic tumor at the subtotal pancreatectomy showed it to be serous cystadenoma with focal atypical lesions. Three years after the operation, however, metastatic liver nodules were found, and the histologic characteristics of these lesions were quite similar to those of the pancreatic neoplasm. Both primary and metastatic tumors were composed of multiple cysts separated by fibrous septa. The epithelium of cysts was cuboidal and had clear cytoplasm, which had positive results for periodic acid-Schiff (PAS) and negative results for PAS with diastase, Alcian blue, and mucicarmine. To the knowledge of the authors, serous cystic neoplasms of the pancreas have been uniformly benign in biologic behavior. Recently, however, serous cystadenocarcinoma of the pancreas has been reported as a new entity. The current case is the second reported case and might support the existence of serous cystadenocarcinoma of the pancreas.

Cystadenocarcinoma

Effect of voluntary exercise on azoxymethane-induced hepatocarcinogenesis in male F344 rats.

The effect of voluntary exercise on azoxymethane-induced hepatocarcinogenesis was investigated in male F344 rats. Beginning at 5 weeks of age, all animals were divided into two groups (sedentary and exercise) and fed AIN-76A semipurified diet ad libitum. At 7 weeks of age, animals were given azoxymethane (AOM) s.c. at a dose level of 15 mg/kg of body weight, once weekly for 2 weeks. Four days after the second dose of AOM, all animals in the exercise group were housed in individual wheel-cage units and the animals in the sedentary group were housed in plastic cages. The experiment was terminated at 38 weeks post-AOM treatment. Body weights of animals in the exercise and sedentary groups were comparable. Immunohistochemical staining of glutathione S-transferase placental form (GST-P) was performed in the liver and measured GST-P positive foci. Density (number of GST-P positive foci/cm2 area of liver section), average area of foci and unit area of foci were significantly inhibited in the exercise group, although the incidence of neoplastic nodules and GST-P positive foci were unaffected by the exercise. Thus, energy expenditure due to exercise may reduce hepatocarcinogenesis in a laboratory animal model.

Animals

Effect of magnesium hydroxide on methylazoxymethanol acetate-induced epithelial proliferation in the large bowels of rats.

The effect of magnesium hydroxide on the epithelial proliferation of the large bowel was examined using rats given methylazoxymethanol (MAM) acetate. Dietary administration of magnesium hydroxide at 250, 500, 1000 or 2000 ppm. for 1, 3 or 5 weeks did not influence the cell cycle of the cryptal cells of the large bowel. However, the exposure to magnesium hydroxide under these conditions lowered the bromodeoxyuridine labeling index of the cells of the large bowel of the rats which had been initiated by MAM acetate (25 mg/kg, 3 times). The decrease in labeling index was more apparent in the proximal segment than in the distal segment. Such an inhibitory effect on the DNA synthesis of the epithelial cells by magnesium hydroxide may be related to the suppressive action of the trace element on the carcinogen-induced large bowel carcinogenesis.

Animals

Cell kinetic analysis of the mucosal epithelium and assay of ornithine decarboxylase activity during the process of 1-hydroxyanthraquinone-induced large bowel carcinogenesis in rats.

Cell kinetics and activity of ornithine decarboxylase (ODC) were studied during the process of 1-hydroxyanthraquinone (1-HA)-induced intestinal carcinogenesis in rats. Starting at 6 weeks of age, a total of 37 male ACI/N rats were divided into two groups and treated as follows: group I (18 rats) received diet containing 1% 1-HA for 12 months; group II (19 rats) was given the basal diet alone. Sub-groups of 5-7 rats were sequentially killed at 4, 8 and 12 months for evaluation of the length, cell numbers and 5-bromo-2'-deoxyuridine (BrDU) labeling indices of large bowel crypts together with ODC activity. All kinetic and ODC data indicated increased DNA synthesis and proliferation at all time points. Morphological observation of the intestines also revealed melanosis, crypt abscesses and erosion, becoming more pronounced with length of exposure to the anthraquinone. The data thus suggest that cell proliferation in the crypts of the cecum or colon is important for 1-HA-induced intestinal carcinogenesis.

Animals