Culture media from hypoxia conditioned mast cells aggravates hypoxia and reoxygenation injury of human intestinal cells.

Intestinal ischemia-reperfusion (II/R) injury is a common clinical and pathological change; however, its underlying mechanisms remain unclear. Previous studies have shown that the inflammatory response induced by mast cell degranulation may be involved in the mechanism underlying II/R injury in rats. In this study, we established a human intestinal epithelial adenocarcinoma cell (Caco-2) hypoxia/reoxygenation (H/R) model and transwell system to investigate the effects of culture media (CM) from hypoxia conditioned human mast cell (HMC-1) and HMC-1 H/R on hypoxia/reoxygenation injury in Caco-2 under H/R conditions. Moreover, we assessed the barrier function of Caco-2 by measuring the 4-kDa fluorescein isothiocyanate (FITC)-dextran (FD4) flux and the tight junction protein expression. The results concluded that Caco-2 exposed to H/R insult showed an increase in lactate dehydrogenase (LDH) release, cell apoptosis index, cell permeability, Bax expression, phosphorylation of c-Jun N-terminal protein kinase (JNK) and p38, and a decrease in cell viability and expression of Bcl-2, ZO1, and occludin (all P < 0.05). Notably, preincubating Caco-2 with HMC-1CM resulted in an increase in cell injury (increased LDH levels and cell permeability, decreased cell viability), apoptosis index, p-JNK, and p-38 expression and a decrease in ZO1 and occludin expression by co-culture system (all P < 0.05). In conclusion, our results show that HMC-1 hypoxic and reoxygenated CM aggravates hypoxic and reoxygenated injury in Caco-2 by increasing the phosphorylation of JNK and p38 in vitro.

Expression of beta-1,4-galactosyltransferase-I affects cellular adhesion in human peripheral blood CD4+ T cells.

beta-1,4-galactosyltransferase-I (beta-1,4-GalT-I) has two isoforms that differ only in the length of their cytoplasmic domains. In this study, we found that both the long and short isoforms of beta-1,4-GalT-I were expressed in human CD4(+) T lymphocytes, and localized in the cytoplasm and on the plasma membrane. The expression level of beta-1,4-GalT-I was increased in CD4(+) T cells after stimulation with interleukin (IL)-2, and was further increased after stimulation with IL-2+IL-12, but decreased after stimulation with IL-2+IL-4 when compared to stimulation with IL-2 alone. We also demonstrated that the cellular adhesion of CD4(+) T cells was significantly increased upon cytokine stimulation, and was inhibited by alpha-lactalbumin, indicating that the increase in adhesion was positively correlated with the expression and activity of long beta-1,4-GalT-I. Collectively, the data suggest that beta-1,4-GalT-I plays a role in the cellular adhesion of CD4(+) T cells.

[Drug effect comparison of Rhubarb extract by the technology free of heating and the extracts form crude Rhubarb and from prepared Rhubarb].

OBJECTIVE: To study the effects of rhubarb extract by the technology free of heating (RETFH) and the extracts from crude rhubarb and from prepared rhubarb on intestine movement and analgesia in mice, and to compare the effects each other. METHODS: Intestine movement was studied by determining the distance in intestine after administrating the extracts from different technology with ink as indicator. Analgesia effect was studied by hot plate test and torsion test induced by acetic acid for the extracts from different technology. RESULTS: Diarrhea effect of low dose (0.75 mg/g) RETFH was moderate, and equal to that of high dose (3.00 mg/g) extract from prepared rhubarb. Remarkable analgesia effect of low dose (0.50 mg/g) RETFH was equal to that of middle and high dose (2.00 mg/g, 4.00 mg/g) extracts from prepared rhubarb and high dose (4.00 mg/g) extract from crude rhubarb. CONCLUSION: 0.50 mg/g RETFH possessed obvious diarrhea and analgesia effects. To utilize the technology free of heating may decrease dosage of rhubarb and save medicinal resource.

[Quantitative determination of ethyl-p-hydroxybenzoate in resins extracted from Dracaena cochinchinensis with two technologies].

OBJECTIVE: Quantitative determination was made of ethyl-p-hydroxybenzoate in Dracaena cochinchinensis extracted with two technologies. METHOD: The sample was resolved with methanol and isolated by TLC, purged with methanol. Tge sample solution was chroma to graphed on a C18 column with acetonitrile-1% acetic acid (31:69) as mobile phase, detecting at 257 nm and content was calculated with external standard method. RESULT: The standard curves of ethyl-p-hydroxybenzoate were linear in the range of 0.206-4.12 ng, r = 0.9998. The average recovery was 97.2% and RSD was 1.4%. CONCLUSION: The content of ethyl-p-hydroxybenzoate in D. cochinchinensis extracted with heating-tree technongy is higher than that with traditional technology.