Relationship between expression of gastrin, somatostatin, Fas/FasL and caspases in large intestinal carcinoma

The effects of modified sini decoction on liver injury and regeneration in acute liver failure induced by D-galactosamine in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Modified sini decoction (MSND) is a well-known traditional Chinese medical formula that has been used to treat cardiovascular and liver diseases for many years. We investigated the effects of MSND on acute liver failure and identified the possible mechanisms of these effects.

MATERIAL AND METHODS

Acute liver failure was induced by intraperitoneal injection of d-galactosamine (d-GalN) into specific pathogen-free male Wistar rats. Next, the rats were treated with Stronger Neo-Minophagen C and MSND via gavage. Biochemical parameters, histological changes in the liver, the survival of rats and the mRNA levels of toll-like receptor 4 (TLR4), nuclear factor kappa B (NF-κB), high mobility group box 1 (HMGB1) caspase-3 and proliferating cell nuclear antigen (PCNA) were analyzed.

RESULTS

MSND prolonged the survival times of the acute liver failure rats. The biochemical parameters were improved, and necrosis in the liver tissues was reduced by both Stronger Neo-Minophagen C (SNMC) and MSND, but MSND induced greater effects. The mRNA expressions of HMGB1, TLR4, NF-κB, and Caspase-3 were remarkably decreased, and the expression of PCNA was remarkably increased by SNMC and MSND, and the effects of MSND were greater.

CONCLUSIONS

MSND protected the liver and increased the survival rate of acute liver failure rats. These effects were likely mediated by the inhibitions of the inflammatory reaction and apoptosis and the promotion of liver tissue regeneration.

Role of ERK-MAPK signaling pathway in pentagastrin-regulated growth of large intestinal carcinoma

AIM: To explore the role and mechanisms of extracellular signal-regulated protein kinase-mitogen-activated protein kinase (ERK-MAPK) signaling in pentagastrin-regulated growth of large intestinal carcinoma.

METHODS: HT-29 cells were incubated in different media and divided into the control group, pentagastrin group, proglumide group, and pentagastrin + proglumide group. No reagent was added to the control group, and other groups were incubated with reagent at different concentrations. Changes in proliferation of HT-29 cells were detected by MTT assay, and the optimal concentrations of pentagastrin and proglumide were determined. The changes in proliferation index (PI) and apoptosis rate (AR) of HT-29 cells were detected by Annexin V-fluorescein isothiocyanate flow cytometry. mRNA expression of pentagastrin receptor/cholecystokinin-B receptor (CCK-BR), ERK1/2 and K-ras were detected by reverse transcriptase polymerase chain reaction. The protein and phosphorylation level of ERK1/2 and K-ras were detected by western blotting. All data were analyzed by analysis of variance and SNK-q test.

RESULTS: The proliferation of HT-29 cells was stimulated by pentagastrin at a concentration of 6.25-100 mg/L, and the optimal concentration of pentagastrin was 25.0 mg/L (F = 31.36, P < 0.05). Proglumide had no obvious effect on the proliferation of HT-29 cells, while it significantly inhibited the proliferation of HT-29 cells stimulated by pentagastrin when the concentration of proglumide was 8.0-128.0 mg/L, and the optimal concentration was 32.0 mg/L (F = 24.31, P < 0.05). The PI of the pentagastrin (25.0 mg/L) group was 37.5% ± 5.2%, which was significantly higher than 27.7% ± 5.0% of the control group and 27.3% ± 5.8% of the pentagastrin (25.0 mg/L) + proglumide (32.0 mg/L) group (Q = 4.56-4.75, P < 0.05). The AR of the pentagastrin (25.0 mg/L) group was 1.9% ± 0.4%, which was significantly lower than 2.5% ± 0.4% of the control group and 2.4% ± 0.3% of the pentagastrin (25.0 mg/L) + proglumide (32.0 mg/L) group (Q = 4.23-4.06, P < 0.05). mRNA expression of CCK-BR was detected in HT-29 cells. The phosphorylation levels of ERK1/2 protein and phosphorylated K-ras protein of the pentagastrin group were 0.43% ± 0.04% and 0.45% ± 0.06%, which were significantly higher than 0.32% ± 0.02% and 0.31% ± 0.05% of the control group (Q = 7.78-4.95, P < 0.05), and 0.36% ± 0.01% and 0.35% ± 0.04% of the pentagastrin + proglumide group (Q = 5.72-4.08, P < 0.05). There were no significant differences in the mRNA and protein expression of ERK1/2 and K-ras among the control, pentagastrin, proglumide and pentagastrin + proglumide groups (F = 0.52, 0.72, 0.78, 0.28; P > 0.05).

CONCLUSION: Gastrin stimulates proliferation of HT-29 cells and inhibits apoptosis by upregulating phosphorylation of ERK and K-ras through the Ras-Raf-MEK1/2-ERK1/2 pathway, and this is restrained by proglumide.