Transgenic expression of human neutrophil peptide-1 enhances hepatic fibrosis in mice fed a choline-deficient, L-amino acid-defined diet.

BACKGROUND: Neutrophils infiltrate the livers of patients with nonalcoholic steatohepatitis (NASH). Human neutrophil peptides (HNPs) induce cytokine and chemokine production under inflammatory conditions, which may contribute to the progression of NASH. In this study, we focused on the effects of HNP-1 on hepatic steatosis and fibrosis in a mouse model of NASH induced by a choline-deficient, L-amino acid-defined (CDAA) diet. MATERIALS & METHODS: We generated transgenic mice expressing HNP-1 under the control of a ß-actin-based promoter. HNP-1 transgenic and wild-type C57BL/6N mice were fed a CDAA diet for 16 weeks to induce hepatic steatosis and fibrosis. Serological and histological features were examined, and the effects of HNP-1 on hepatic stellate cell lines were assessed. RESULTS: HNP-1 transgenic and wild-type mice fed the CDAA diet showed no significant differences in serum alanine aminotransferase levels or the degree of hepatic steatosis based on Oil red O staining and hepatic triglyceride content. In contrast, Sirius Red and Azan staining showed significantly more severe hepatic fibrosis in HNP-1 transgenic mice compared with wild-type mice. In addition, significantly more α-smooth muscle actin-positive hepatic stellate cells were observed in the transgenic mice than in the wild-type mice. Finally, the proliferation of the LI90 hepatic stellate cell line increased in response to HNP-1. CONCLUSION: Our data indicate that HNP-1 enhances hepatic fibrosis in fatty liver by inducing hepatic stellate cell proliferation. Thus, neutrophil-derived HNP-1 may contribute to the progression of NASH.

Helicobacter pylori eradication improves the quality of life regardless of the treatment outcome: A multicenter prospective cohort study.

Helicobacter pylori (Hp) eradication is recommended for improving the quality of life (QOL) of patients with epigastric symptoms, especially reflux and dyspepsia. However, no reports have investigated the improvement of QOL after the eradication of Hp irrespective of epigastric symptoms. The aim of this study was to investigate the improvement in the QOL after the eradication of Hp irrespective of epigastric symptoms, and evaluate the factors associated with an improved QOL after the eradication of Hp.This prospective cohort study was performed at 15 referral institutions from September 2013 to December 2014. The patients' QOL and epigastric symptoms were evaluated before and after the eradication of Hp using the 8-item Short-Form Health Survey (SF-8) and the modified Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease, respectively.One hundred sixty-five of 184 Hp-infected patients underwent Hp eradication treatment. The treatment was successful in 82.4% (136/165) of the cases. One hundred sixty of the 165 Hp-infected patients were eligible for inclusion in the QOL analysis. In the indices of QOL on the SF-8, the scores on both the mental component summary (MCS) and the physical component summary (PCS) were found to have significantly improved after the eradication of Hp. However, the epigastric symptoms before the eradication of Hp were not correlated with either the MCS or PCS. A low QOL value before the eradication of Hp was the factor what was most strongly associated with the improvement in the QOL.The eradication of Hp improved the QOL, regardless of the outcome of the treatment, especially in patients who had an impaired QOL before the eradication.

A reduction-triggered delivery by a liposomal carrier possessing membrane-permeable ligands and a detachable coating.

To control the cellular uptake of drugs and genes, we synthesized a liposomal carrier possessing membrane-permeable ligands and a detachable poly(ethylene glycol) (PEG) coating. For the detachable coating, a lipid having a thiolytic cleavable spacer (PEG-S-S-DOPE) was synthesized by the reaction of dioleoylphosphatidylethanolamine (DOPE) with a PEG chain via a disulfide linkage. The liposomes were prepared from a mixture of dipalmitoylphosphatidylcholine (DPPC), DOPE, PEG-S-S-DOPE, and cholesteryl hemisuccinate (CHEMS). The octamer (R8 peptide) of arginine was chosen as the membrane-permeable ligand and covalently immobilized onto the CHEMS portion of the liposome surface (PEG-S-S-R8-liposome). The disulfide bond of the PEG chain was cleaved to display the R8 peptides on the liposome surface by adding a reducing agent such as L-cysteine, and thereby internalization of the liposomes was significantly facilitated. When L-cysteine was added to the mixture of cells and the liposome that incorporated plasmids encoding the enhanced green fluorescence protein (pEGFP), the expression of EGFP was low but could be observed in almost 100% of the cells.

Low concentrations of human neutrophil peptide ameliorate experimental murine colitis.

Human neutrophil peptides (HNPs) not only have antimicrobial properties, but also exert multiple immunomodulatory effects depending on the concentration used. We have previously demonstrated that the intraperitoneal administration of high-dose HNP-1 (100 µg/day) aggravates murine dextran sulfate sodium (DSS)-induced colitis, suggesting a potential pro-inflammatory role for HNPs at high concentrations. However, the role of low physiological concentrations of HNPs in the intestinal tract remains largely unknown. The aim of this study was to examine the effects of low concentrations of HNPs on intestinal inflammation. We first examined the effects of the mild transgenic overexpression of HNP-1 in DSS-induced colitis. HNP-1 transgenic mice have plasma HNP-1 levels similar to the physiological concentrations in human plasma. Compared to wild-type mice treated with DSS, HNP-1 transgenic mice treated with DSS had significantly lower clinical and histological scores, and lower colonic mRNA levels of pro-inflammatory cytokines, including interleukin (IL)-1ß and tumor necrosis factor (TNF)-α. We then injected low-dose HNP-1 (5 µg/day) or phosphate-buffered saline (PBS) intraperitoneally into C57BL/6N and BALB/c mice administered DSS. The HNP-1-treated mice exhibited significantly milder colitis with reduced expression levels of pro-inflammatory cytokines compared with the PBS-treated mice. Finally, we examined the in vitro effects of HNP-1 on the expression of cytokines associated with macrophage activation. Low physiological concentrations of HNP-1 did not significantly affect the expression levels of IL-1ß, TNF-α, IL-6 or IL-10 in colonic lamina propria mononuclear cells activated with heat-killed Escherichia coli, suggesting that the anti-inflammatory effects of HNP-1 on murine colitis may not be exerted by direct action on intestinal macrophages. Collectively, our data demonstrated a biphasic dose-dependent effect of HNP-1 on DSS-induced colitis: an amelioration at low concentrations and an aggravation at high concentrations. Low concentrations of HNPs may contribute to the maintenance of intestinal homeostasis.

Human neutrophil peptides induce interleukin-8 in intestinal epithelial cells through the P2 receptor and ERK1/2 signaling pathways.

Human neutrophil peptides (HNPs) are antimicrobial peptides produced predominantly by neutrophils. We have previously reported that HNP 1-3 levels are increased in the sera and plasma of patients with active ulcerative colitis. The increased expression of interleukin-8 (IL-8) has also been demonstrated in the colonic mucosa of patients with active ulcerative colitis. HNPs induce IL-8 in lung epithelial cells and monocytes through the P2Y6 signaling pathway. However, the association between HNPs and IL-8 in the intestinal mucosa has not yet been investigated. In the present study, we investigated the effects of HNP-1 on the production of IL-8 by human intestinal epithelial cells and the underlying signaling mechanisms. We observed a significant increase in IL-8 expression in the human colon carcinoma cell line, Caco-2, following treatment with HNP-1. The non-selective P2 receptor antagonists, suramin and pyridoxal phosphate-6-azo (benzene-2,4-disulfonic acid) tetrasodium salt hydrate (PPADS), significantly blocked the HNP-1-induced expression of IL-8 in the Caco-2 cells. The P2Y6-specific antagonist, MRS2578, led to a significant but partial decrease in IL-8 expression, suggesting that P2 receptors in addition to P2Y6 are involved in the HNP-1-induced production of IL-8 by Caco-2 cells. In agreement with this finding, HNP-1 also significantly increased IL-8 production in the P2Y6-negative human colon cancer cell line, HT-29, and this increase was blocked by treatment with suramin and PPADS. HNP-1 significantly increased the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) and p38 mitogen-activated protein kinase (MAPK) in the HT-29 cells. However, the HNP-1-induced production of IL-8 was suppressed by the ERK1/2 inhibitor, U0126, but not by the p38 MAPK inhibitor, SB203580. In conclusion, our data demonstrate that HNP-1 induces IL-8 production not only through P2Y6, but also through additional P2 receptors via an ERK1/2-dependent mechanism in intestinal epithelial cells.