Role of mast cell-miR-490-5p in irritable bowel syndrome.

AIM: To determine the functional role of miR-490-5p in mast cell proliferation and apoptosis, and in the mast cell tryptase/PAR-2 signal pathway. METHODS: The 3rd generation of lentivirus vector systems containing enhanced green fluorescent protein (EGFP) (Ruisai Inc., Shanghai, China), which acts as a reporter gene was used to construct the mmu-miR-490-5p lentivirus expression vector pEGFP-antagomiR-490-5p, and the lentivirus vector pEGFP-negative was used as a negative control. The stably transfected mast cell line p815 was then constructed. GFP positive cells were successfully transfected cells. We determined the expression of miR-490-5p in p815 mast cells before and after transfection using quantitative real-time PCR (qRT-PCR). In addition, after transduction with the lentivirus vectors, the role of miR-490-5p in mast cell proliferation and apoptosis was investigated using the CCK-8 assay and flow cytometry, respectively. The mRNA levels of tryptase and PAR-2 were detected by qRT-PCR and the protein levels were detected by Western blot. RESULTS: The inhibition of miR-490-5p expression promoted apoptosis and inhibited proliferation of p815 mast cells. The mRNA levels of tryptase and PAR-2 were significantly increased after transfection compared with the control group, tryptase (P = 0.721, normal vs null; P = 0.001, siRNA vs normal; P = 0.002, siRNA vs null) and PAR-2 (P = 0.027, siRNA vs null; P = 0.353, normal vs null; P = 0.105, siRNA vs normal). The protein levels of tryptase and PAR2 were slightly higher in the siRNA group than those in the control group, but the difference was not statistically significant (P > 0.05). CONCLUSION: miR-490-5p plays a vital role in the pathogenesis of irritable bowel syndrome by affecting mast cell proliferation and apoptosis; with down-regulation of miR-490-5p, the mRNA level of mast cell tryptase and PAR-2 increased, and the protein level increased, but the difference was not statistically significant.

Tryptase and Protease-Activated Receptor 2 Expression Levels in Irritable Bowel Syndrome.

BACKGROUND/AIMS: Previous studies have revealed that mast cells (MCs) may activate the protease-activated receptors and release of neuropeptides involved in the pathogenesis of irritable bowel syndrome (IBS). The levels of proteaseactivated receptor 2 (PAR-2) and tryptase can contribute to understanding the pathogenesis of IBS. METHODS: Colonoscopic biopsies were performed of 38 subjects (20 with IBSdiarrhea [IBS-D], eight with IBS-constipation [IBS-C], and 10 healthy volunteers). The mRNA and protein levels of tryptase and PAR-2 were assessed by real-time PCR and Western blot. The levels of vasoactive intestinal peptide (VIP), substance P (SP), and calcitonin gene-related peptide (CGRP) were measured by immunohistochemistry, and MCs were counted by toluidine blue staining. RESULTS: Significant increases in the mRNA expression of tryptase (p<0.05, IBS-D, IBS-C vs control) and PAR-2 (p<0.05, IBS-D, IBS-C vs control) and in the tryptase protein level (p<0.05, IBS-D, IBS-C vs control) were detected in IBS. Elevations of MCs, CGRP, VIP and SP (p<0.05, IBS-D vs control) were observed for IBS-D only. CONCLUSIONS: Tryptase levels may upregulate the function of PAR- 2, resulting in the release of neuropeptide and they were correlated with clinical symptoms associated with IBS.

Autophagy inhibition contributes to the synergistic interaction between EGCG and doxorubicin to kill the hepatoma Hep3B cells.

(-)-Epigallocatechin-3-O-gallate(EGCG), the highest catechins from green tea, has promisingly been found to sensitize the efficacy of several chemotherapy agents like doxorubicin (DOX) in hepatocellular carcinoma (HCC) treatment. However, the detailed mechanisms by which EGCG augments the chemotherapeutic efficacy remain unclear. Herein, this study was designed to determine the synergistic impacts of EGCG and DOX on hepatoma cells and particularly to reveal whether the autophagic flux is involved in this combination strategy for the HCC. Electron microscopy and fluorescent microscopy confirmed that DOX significantly increased autophagic vesicles in hepatoma Hep3B cells. Western blot and trypan blue assay showed that the increasing autophagy flux by DOX impaired about 45% of DOX-induced cell death in these cells. Conversely, both qRT-PCR and western blotting showed that EGCG played dose-dependently inhibitory role in autophagy signaling, and that markedly promoted cellular growth inhibition. Amazingly, the combined treatment caused a synergistic effect with 40 to 60% increment on cell death and about 45% augmentation on apoptosis versus monotherapy pattern. The DOX-induced autophagy was abolished by this combination therapy. Rapamycin, an autophagic agonist, substantially impaired the anticancer effect of either DOX or combination with EGCG treatment. On the other hand, using small interference RNA targeting chloroquine autophagy-related gene Atg5 and beclin1 to inhibit autophagy signal, hepatoma cell death was dramatically enhanced. Furthermore, in the established subcutaneous Hep3B cells xenograft tumor model, about 25% reduction in tumor growth as well as 50% increment of apoptotic cells were found in combination therapy compared with DOX alone. In addition, immunohistochemistry analysis indicated that the suppressed tendency of autophagic hallmark microtubule-associated protein light chain 3 (LC3) expressions was consistent with thus combined usage in vitro. Taken together, the current study suggested that EGCG emerges as a chemotherapeutic augmenter and synergistically enhances DOX anticancer effects involving autophagy inhibition in HCC.

[The effects of Chinese national medicine of Huoxueruanjian compound on SMAD signal in hepatic stellate cell and its significance].

OBJECTIVE: In order to explore the roles of Huoxueruanjian compound on liver fibrogenesis and its molecular mechanism, this paper has investigated the Influence of blood serum with such traditional Chinese medicine compound on the expression of Smad3, Smad7 and procollagen alpha2(I) gene in hepatic stellate cell (HSC). METHODS: HSC-T6 was deal with different Concentration of blood serum medicine with Heluoshugan which was made by routine way. Then expression change of Smad3, Smad7 and procollagen alpha2(I) mRNA among each groups were observed by RT-PCR. Furthermore, the expression change of Smad3 protein were examined by Western blot. RESULTS: Expression of Smad3 and procollagen alpha2(I) mRNA as well as Smad3 protein had been downregulated after treating with blood serum medicine of Heluoshugan (P<0.01, P<0.05, respectively). The expression of procollagen alpha2(I) mRNA changed at the same tendency as those of Smad3. The role of blood serum medicine was significant difference between different concentration, P<0.05. And the expression of procollagen alpha2(I) mRNA changed in concentration-dependent manner. Blood serum medicine has no effects on the Smad7 mRNA. CONCLUSION: The anti-fibrosis roles of HuoXueruanjian Compound maybe influence the function of TGF-beta and Smad by nonspecific action, thereby inhibit the transcription of procollegan alpha2(I) mRNA and decrease the production of ECM. As regards Smad3, it may be facilitating the development of liver fibrosis when its expression increases. Otherwise, it manifest with anti-fibrosis role.