High-fat diet is one of the causes of nonalcoholic fatty liver disease. We have previously demonstrated that high-fat diet induces upregulation of adipose differentiation-related protein mRNA expression accompanied by lipid droplet formation in mouse liver. Vanin-1 is a ubiquitous epithelial ectoenzyme that has pantetheinase activity and produces cysteamine, a potent endogenous antioxidant. In the present study, we analyzed the expression of hepatic vanin-1 mRNA following the administration of a high-fat diet in mice as well as free fatty acids in hepatocyte cultures and speculated its possible mechanism. Vanin-1 mRNA levels in the livers of mice were upregulated within a day of the high-fat diet, even before the expression of adipose differentiation-related protein mRNA and lipid accumulation. An in vitro analysis using HuH-7 cells revealed a significant upregulation of vanin-1 mRNA by as low as 0.01 mM oleic acid; however, lipid accumulation in hepatocytes was not affected at this concentration. Furthermore, vanin-1 mRNA was differentially upregulated by various free fatty acids irrespective of the grade of lipid accumulation. These findings indicate that the upregulation of vanin-1 precedes lipid accumulation and is differentially mediated by various types of free fatty acids in the model, presenting vanin-1 as a novel player in the pathogenesis of nonalcoholic fatty liver disease.
Electron spin resonance measurements were performed for the reactions of some endogenous photosensitizers (flavin mononucleotide or flavin adenine dinucleotide or folic acid or β-nicotinamide adenine dinucleotide or β-nicotinamide adenine dinucleotide phosphate or pyridoxal-5'-phosphate or urocanic acid) with oleic acid under the ultraviolet light A irradiation using α-(4-pyridyl-1-oxide)-N-tert-butylnitrone as a spin trap reagent. Of the endogenous photosensitizers, prominent electron spin resonance signals (αN = 1.58 mT and αHβ = 0.26 mT) were observed for the reaction mixture of flavin mononucleotide (or flavin adenine dinucleotide or folic acid), suggesting that radical species form in the reaction mixtures. Singlet oxygen seems to participate in the formation of the radicals because the electron spin resonance peak heights increased for the reactions in D2O to a great extent. A high performance liquid chromatography-electron spin resonance-mass spectrometry was employed to identify the radicals formed in the reactions of the endogenous photosensitizers (flavin mononucleotide or flavin adenine dinucleotide or folic acid) with oleic acid under the ultraviolet light A irradiation. The high performance liquid chromatography-electron spin resonance-mass spectrometry analyses showed that 7-carboxyheptyl and 1-(3-carboxypropyl)-4-hydroxybutyl radicals form in the reaction mixture of flavin mononucleotide (or flavin adenine dinucleotide or folic acid).
We administered zinc supplementation therapy over three years to patients with chronic hepatitis C and reported and that the aspartate aminotransferase (AST) and alanine aminotaransferase (ALT) levels decreased, and platelet counts increased, significantly in the group with increased serum zinc concentrations. We are continuing this treatment to clarify the long-term consequences and report here the changes in serum zinc concentrations over seven years and compare the cumulative incidence of hepatocellular carcinoma (HCC). We administered polaprezinc to 32 patients, randomly selected for zinc therapy (treatment group), while another 30 formed the control group. We measured the serum zinc and albumin concentrations and conducted a prospective study to determine long-term outcomes. The changes and rates of change of serum zinc concentrations after seven years were 76.7 ± 18.2 μg/dl and +0.302 ± 0.30% in the treatment group and 56.7 ± 12.4 μg/dl and +0.033 ± 0.21% in the control group and had increased significantly (p = 0.0002, p = 0.0036). Progression of liver disease seemed to vary, depending on serum albumin concentrations. In the group with baseline serum albumin concentrations of 4.0 g/dl or more, the change and rate of change of serum zinc concentrations increased significantly, and the cumulative incidence of HCC tended to decrease, in the treated group. According to multivariate analysis, the factors that contribute to a reduction in the incidence of HCC are zinc therapy (risk ratio: 0.113, 95% CI: 0.015–0.870, p = 0.0362), and platelet counts (0.766, 0.594–0.989, 0.0409). Zinc supplementation therapy seems to improve liver pathology and reduce the incidence of HCC.
In our previous study, the healing effect of proton pump inhibitor plus rebamipide for endoscopic submucosal dissection-related artificial ulcer smaller than 40 mm showed statistical significance. However, such effect of the combination was not yet clear for ulcers with dissected diameter more than 40 mm. The aim of this present study was to resolve this problem under sufficient statistical power, with adequate sample size. We conducted a randomized controlled study. Either the proton pump inhibitor mono-therapy or the combination therapy was prescribed for 28 days after endoscopic submucosal dissection. Eighty-seven patients were eligible for outcome evaluation. Combination therapy was significantly superior to mono-therapy, 27.8% vs 0% reached healing stage (scar stage) in cases with ulcers of dissection diameter more than 40 mm. In conclusion, the combination therapy with rebamipide was favorable regimen in patients with larger artificial ulcer after endoscopic submucosal dissection.
Helicobacter pylori (H. pylori) eradication therapy alone is insufficient to ensure healing of large ulcers with H. pylori-positive gastric ulcer (GU). The question of what is the optimum antiulcer treatment following H. pylori eradication therapy has not been fully elucidated. Furthermore, the ulcer healing effects of eradication therapy itself with H. pylori-positive duodenal ulcer (DU) have not been investigated. In GU study, the eradication therapy + proton pump inhibitor (PPI) group (group A) were administered eradication therapy followed by 7 weeks of a PPI, and the eradication therapy + gastroprotective drug (GP) group (group B) eradication therapy followed by 7 weeks of a GP. In DU study, the eradication therapy + PPI group (group C) were administered eradication therapy followed by 5 weeks of a PPI, and the eradication therapy only group (group D) was eradication therapy alone. In GU study, healing rates for ulcer of ≥15 mm in diameter were significant greater in the group A. In DU study, high healing rates were seen both the group C and D. In conclusion, a PPI could significantly heal GU than a GP after eradication therapy in GU. Meanwhile, the eradication alone is sufficient for DU.
Bisphosphonates such as alendronate and risedronate are commonly used for the treatment of postmenopausal osteoporosis. They have the gastrointestinal adverse effects such as erosions and ulcers in stomach and small intestine. However, the detailed biological mechanism remains to be elucidated. Since alendronate is suggested to increase the risk of non-steroidal anti-inflammatory drug-related gastropathy, we hypothesized that bisphosphonates and non-steroidal anti-inflammatory drugs have the same pathophysiological mechanisms in gastrointestinal mucosa: Bisphosphonates may induce cellular lipid peroxidation by inducing the production of mitochondrial superoxide. We also hypothesized that geranylgeranylacetone, an antiulcer drug, may prevent lipid peroxidation by reducing superoxide production. We treated gastric RGM1 cells and small intestinal IEC6 cells with alendronate or risedronate, and examined cellular injury, lipid peroxidation and superoxide production with specific fluorescent dyes, and underwent electron paramagnetic resonance spectroscopy to detect the production of superoxide in vitro. The results indicated that bisphosphonates indeed induced cellular injury, cellular lipid peroxidation, and superoxide production. We also demonstrated that the pretreatment of geranylgeranylacetone decreased superoxide production and prevented cellular lipid peroxidation. These results suggested that bisphosphonates, like non-steroidal anti-inflammatory drugs, induce lipid peroxidation by producing mitochondrial superoxide, which was prevented by geranylgeranylacetone.
Functional disorders of various immune cells have been reported in hepatocellular carcinoma (HCC) patients. Recently, distinct subsets of neutrophils (polymorphonuclear leukocytes, PMN) have been identified in hosts with enhanced or impaired cell-mediated immunity. In this study, therefore, plasma factors and PMN from HCC patients were immunobiologically investigated. Plasma neopterin and CCL17 levels were measured by ELISA in 95 HCC patients. Peripheral PMN were isolated from each HCC patient and tested for CCL2 or CCL3 production by ELISA and flow cytometry. The results showed elevated plasma neopterin levels in HCC patients, while CCL17 levels decreased in correlation with tumor size. PMN from HCC patients produced CCL2, while PMN from healthy subjects did not. Moreover, CCL2 production by PMN was significantly increased in proportion to tumor load. When HCC patients were divided into two groups based on CCL2 produced by PMN, the survival rate of the CCL2 high group was significantly lower than that for other patients. While CCL3 production by PMN was also significantly increased in HCC patients, their CCL3 production did not correlate with tumor load and survival. The CCL2/CCL3 ratio in culture fluids of each PMN was also increased in proportion to tumor size. These results suggest that cell-mediated immunity may be impaired in advanced HCC patients. Moreover, distinct PMN subsets may exist in the peripheral blood of HCC patients. These PMN subsets, especially CCL2-producing PMN, may be involved in tumor extension and the survival outcomes for HCC patients.
Enteral feeding has become an important means of providing nutritional support to seriously ill patients. Placement of the feeding tube through the pyloric ring and past the ligament of Treitz into the proximal jejunum is critical to reduce the risk of gastroesophageal regurgitation and microaspiration. We started utilizing transnasal endoscopy for intestinal feeding tube placement, placing enteral tubes for 40 patients between March 2008 and February 2009. Although we achieved a high success rate comparable to previous reports, we experienced several cases of failure, which was corrected with repeated endoscopy. Based on these experiences, we modified our method by adding a “double-check” transnasal endoscopy through the other nasal passage. After April 2010, we have placed the feeding tube by “double-check” method for all patients (more than 40 patients) who required transnasal endoscopic feeding tube placement. We have not experienced any misplacement in all these patients after 24 h later with 100% successful rate since the introduction of “double-check” procedure. We describe our experience with “double-check” transnasal endoscopic feeding tube placement, which we found to be a helpful adjunct, for patients in intensive care unit.
Gastrointestinal symptoms are a problematic issue for patients who take low-dose aspirin for long time. We conducted a pilot study to investigate the efficacy of combination therapy with proton pump inhibitor and rebamipide. This was a prospective, randomized, double-blind, placebo-controlled cross-over study. All the subjects received aspirin 100 mg and omeprazole 20 mg. The subjects were divided into two groups and received either rebamipide 300 mg or placebo, which was prescribed for 4 weeks. The subjects were instructed to record their gastrointestinal symptom rating scale before the study and 1 and 4 weeks after beginning the protocol. These scores of the groups were compared before and after the treatment to evaluate the severity of their symptoms and the number of symptom items present in each group. For the subjects receiving rebamipide, the total prevalence of lower gastrointestinal symptoms was significantly different from the placebo group (p=0.0093) at week 4. No troublesome symptoms were observed in the rebamipide group. Inconclusion, the administration of rebamipide prevented the occurrence of troublesome symptoms, especially lower gastrointestinal symptoms, in patients taking aspirin and omeprazole. Rebamipide is a candidate drug for combination therapy with proton pump inhibitors to prevent low-dose aspirin-induced gastrointestinal symptoms.
The inhalation of asbestos is a risk factor for the development of malignant mesothelioma and lung cancer. Based on the broad surface area of asbestos fibers and their ability to enter the cytoplasm and nuclei of cells, it was hypothesized that proteins that adsorb onto the fiber surface play a role in the cytotoxicity and carcinogenesis of asbestos fibers. However, little is known about which proteins adsorb onto asbestos. Previously, we systematically identified asbestos-interacting proteins and classified them into eight sub-categories: chromatin/nucleotide/RNA-binding proteins, ribosomal proteins, cytoprotective proteins, cytoskeleton-associated proteins, histones and hemoglobin. Here, we report an adsorption profile of proteins for the three commercially used asbestos compounds: chrysotile, crocidolite and amosite. We quantified the amounts of adsorbed proteins by analyzing the silver-stained gels of sodium dodecyl sulfate-polyacrylamide gel electrophoresis with ImageJ software, using the bands for amosite as a standard. We found that histones were most adsorptive to crocidolite and that chromatin-binding proteins were most adsorptive to chrysotile. The results suggest that chrysotile and crocidolite directly interact with chromatin structure through different mechanisms. Furthermore, RNA-binding proteins preferably interacted with chrysotile, suggesting that chrysotile may interfere with transcription and translation. Our results provide novel evidence demonstrating that the specific molecular interactions leading to carcinogenesis are different between chrysotile and crocidolite.
The pathogenesis of nonalcoholic steatohepatitis (NASH) remains unclear, but accumulating data suggest oxidative stress and the relationship between inflammation and immunity plays a crucial role. The aim of this study is to investigate the spirulina, which is a blue-green algae rich in proteins and other nutritional elements, and its component-phycocyanin effect on a rat model of NASH. NASH model rats were established by feeding male Wistar rats with choline-deficient high-fat diet (CDHF) and intermittent hypoxemia by sodium nitrite challenge after 5 weeks of CDHF. After experimental period of 10 weeks, blood and liver were collected to determine oxidative stress injuries and efficacies of spirulina or phycocyanin on NASH model rats. In the NASH model rats, increase in plasma liver enzymes and liver fibrosis, increases in productions of reactive oxygen species from liver mitochondria and from leukocytes, the activation of nuclear factor-kappa B, and the change in the lymphocyte surface antigen ratio (CD4+/CD8+) were observed. The spirulina and phycocyanin administration significantly abated these changes. The spirulina or phycocyanin administration to model rats of NASH might lessen the inflammatory response through anti-oxidative and anti-inflammatory mechanisms, breaking the crosstalk between oxidative stress and inflammation, and effectively inhibit NASH progression.
The comparative effects of doenjang prepared from fermented soybean or brown rice on the body weight and lipid metabolism in C57BL/6N mice fed with high fat diet were investigated. The animals were randomly divided and given experimental diets for eight weeks: normal control diet, high fat diet, and high fat diet supplemented with soybean doenjang, brown rice doenjang, brown rice-rice bran doenjang, or brown rice-red ginseng marc doenjang. At the end of the experimental period, the HF group exhibited a marked increase in body weight, body fat, plasma triglyceride concentration, and atherogenic index relative to the normal control diet group. However, diet supplementation of doenjang counteracted this high fat-induced hyperlipidemia through modulation of lipogenesis and adipokine production. In general, compared with soybean doenjang, the brown rice-rice bran doenjang and brown rice-red ginseng marc doenjang were similarly effective in improving the lipid metabolism under high fat diet condition. These findings demonstrate that brown rice, in combination with rice bran or red ginseng marc, may be useful as a functional biomaterial for the preparation of doenjang with strong anti-obesity effect and hypolipidemic action.
We previously demonstrated that a diet containing fish oil at a level of 80 g/kg strongly stimulated the physiological activity of a sesame sesamin preparation containing sesamin and episesamin at equal amounts to increase hepatic fatty acid oxidation. This study was conducted to clarify whether fish oil at lower dietary levels enhances the physiological activity of sesamin to increase hepatic fatty acid oxidation. Rats were fed experimental diets supplemented with 0 or 2 g sesamin/kg, and containing 0, 15 or 30 g fish oil/kg for 15 days. Among rats fed sesamin-free diets, diets containing 15 and 30 g fish oil/kg slightly increased the activity of enzymes involved in hepatic fatty acid oxidation. Sesamin increased these values irrespective of the presence or absence of fish oil in diets; however, the extent of the increase of many parameters was much greater in rats given fish oil-containing diets than in those fed a fish oil-free diet. Diets simultaneously containing sesamin and fish oil increased the gene expression of various peroxisomal fatty acid oxidation enzymes in a synergistic manner; but they were ineffective in causing a synergistic increase in mRNA levels of mitochondrial fatty acid oxidation enzymes. The extent of the synergistic increase in the activity of hepatic fatty acid oxidation enzymes and mRNA levels of the peroxisomal enzymes was indistinguishable between diets containing 15 and 30 g fish oil/kg and appeared comparable to that observed previously with a diet containing 80 g fish oil/kg.
In the article by Sakuragawa et al. (Journal of Clinical Biochemistry and Nutrition 2010; 46: 126–134) “Hypotaurine is an Energy-Saving Hepatoprotective Compound against Ischemia-Reperfusion Injury of the Rat Liver”, an error appeared in Fig. 4. Units of the ordinates in Fig. 4 were incorrect: i.e. it should be μmol/g liver instead of mmol/g liver. A corrected figure and legend are printed below.