RESUMEN
The common lipopolysaccharide (LPS)-induced gastric lesions, such as erosions or ulcers, have been investigated in depth. Little is known, however, about the acute gastric lesions following a high dose of LPS. In a time-course study, ICR female mice were given a high subcutaneous dose of LPS (50 mg/kg). Mice were sacrificed at 4, 6, 12, and 24 hours after dosing and were assessed histopathologically for acute gastric lesions. The major gastric changes were seen in the fundic region and included vacuolar degeneration of parietal cells and apoptosis of chief cells. The vacuole in parietal cells was apparent as early as 4 hours postinjection (PI), and apoptosis of chief cells was apparent at 12 hours PI. Thrombus formation, in contrast, was not seen until 24 hours PI. No erosion, ulcer, or hemorrhage was seen in any gastric region in any of the treated animals at 24 hours PI. These results indicate that a subcutaneous high dose of LPS in mice causes vacuolar degeneration of parietal cells and apoptosis of chief cells before thrombus formation or subsequent ulcerative lesions.
Asunto(s)
Células Principales Gástricas/efectos de los fármacos , Escherichia coli , Lipopolisacáridos/toxicidad , Células Parietales Gástricas/efectos de los fármacos , Trombosis/inducido químicamente , Enfermedad Aguda , Animales , Apoptosis/efectos de los fármacos , Recuento de Células Sanguíneas/efectos de los fármacos , Temperatura Corporal/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Células Principales Gástricas/química , Células Principales Gástricas/patología , Gránulos Citoplasmáticos/química , Femenino , ATPasa Intercambiadora de Hidrógeno-Potásio/análisis , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Ratones , Ratones Endogámicos ICR , Células Parietales Gástricas/química , Células Parietales Gástricas/patología , Pepsina A/análisis , Trombosis/patologíaRESUMEN
Antitumor activities of zinostatin stimalamer (YM881) were examined in human hepatoma cell lines (SK-Hep1 and HuH2) and VX2 liver tumor-bearing rabbits. YM881 inhibited the growth of human hepatoma cells in a dose-dependent manner. The IC50 values of YM881 causing a 50% inhibition of growth of SK-Hep1 and HuH2 cells were 6.7 and 27 nM, respectively. In VX2 tumor-bearing rabbits, administration of YM881 suspended in Lipiodol, an iodinated fatty acid ethylester of poppyseed oil, (YM881/Lipiodol suspension, 0.2 mg/0.2 ml/body) into the hepatic artery showed significant (p < 0.01, vs. sham-operated and Lipiodol-treated groups) inhibitory effects on tumor growth and histopathological changes at 1 and 2 weeks after administration. In contrast, Lipiodol (0.2 ml/body) tended to inhibit the growth of VX2 tumor (p < 0.1, vs. sham-operated group) at 1 week after administration, but showed only moderate effects at 2 weeks after administration. Minimal necrosis was observed at 1 and 2 weeks after administration of Lipiodol, and histopathological findings were similar to those in the sham-operated group. From the present study, it is suggested that YM881/Lipiodol suspension showed antitumor activity in VX2 tumor-bearing rabbits presumably due to the inhibition of the growth of hepatoma cells by YM881 itself. Lipiodol, on the other hand, is considered to augment the antitumor activity of YM881 by maintaining high YM881 concentrations in tumor tissue.
Asunto(s)
Antineoplásicos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Anhídridos Maleicos/farmacología , Poliestirenos/farmacología , Cinostatina/análogos & derivados , Animales , División Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Aceite Yodado/farmacología , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Masculino , Trasplante de Neoplasias , Conejos , Suspensiones , Células Tumorales Cultivadas , Cinostatina/farmacologíaRESUMEN
Anti-tumor activities of zinostatin stimalamer (YM 881) were examined using human hepatoma cell lines (SK-Hep1 and HuH 2) and VX2 liver tumor-bearing rabbits. YM881 inhibited the growth of human hepatoma cells in a dose-dependent manner. The IC50 values of YM881 against SK-Hep 1 and HuH 2 cells were 6.7 and 27 mM, respectively. In VX2 tumor-bearing rabbits, administration of YM 881 suspended in iodinated fatty acid ethylesters of poppyseed oil (YM 881/Lipiodol suspension, 0.2 mg/0.2 ml/body) into the hepatic artery showed significant (p < 0.01, vs sham-operated and Lipiodol-treated groups) inhibitory effects on the growth and pathological changes 1 and 2 weeks after administration. On the other hand, Lipiodol (0.2 ml/body) showed a tendency to inhibit the growth of VX2 tumor (p < 0.1, vs sham-operated group) 1 week after administration, but it showed only moderate effects on the VX2 tumor growth 2 weeks after administration. Minimal necrosis was observed 1 and 2 weeks after administration of Lipiodol, and these pathological findings were similar to those in the sham-operated group. From the present study, it is suggested that YM 881/Lipiodol suspension showed the anti-tumor activity against VX2 tumor-bearing rabbits, presumably due to the inhibition of the growth of hepatoma cell by YM 881 per se. On the other hand, Lipiodol is considered to augment the anti-tumor activity by maintaining high YM881 concentrations in tumor tissue.