Taurine (2-aminoethylsulfonic acid) has many physiological and pharmacological functions in most tissues. It is abundantly maintained in the liver by both endogenous biosynthesis and exogenous ...transport, but is decreased in liver diseases. In the hepatic lobule, there are heterogeneous differences in metabolism between the pericentral (PC) and periportal regions, and the distributions of the biosynthesis capacity and specific taurine transporter expression are predominantly in the PC region. In cases of depletion of hepatic taurine level, serious liver damages were observed in the PC region. Taurine has protective effects against xenobiotics-induced liver damages in the PC region, but not xenobiotics-induced PP region damages. The xenobiotics that injure the PC region are mainly catabolized by NADPH-dependent cytochrome P450 2E1 that is also predominantly expressed in the PC region. Taurine treatment seems to be a useful agent for CYP2E1-related liver diseases with predominant damages in the PC region.
Gut microbiota have profound effects on bile acid metabolism by promoting deconjugation, dehydrogenation, and dehydroxylation of primary bile acids in the distal small intestine and colon. High-fat ...diet-induced dysbiosis of gut microbiota and bile acid dysregulation may be involved in the pathology of steatosis in patients with non-alcoholic fatty liver disease. Epigallocatechin-3-gallate (EGCG), the most abundant polyphenolic catechin in green tea, has been widely investigated for its inhibitory or preventive effects against fatty liver. The aim of the present study was to investigate the effects of EGCG on the abundance of gut microbiota and the composition of serum bile acids in high-fat diet-fed mice and determine the specific bacterial genera that can improve the serum bile acid dysregulation associated with EGCG anti-hepatic steatosis action. Male C57BL/6N mice were fed with the control diet, high-fat diet, or high-fat diet + EGCG at a concentration of 0.32% for 8 weeks. EGCG significantly inhibited the increases in weight, the area of fatty lesions, and the triglyceride content in the liver induced by the high-fat diet. Principal coordinate analysis revealed significant differences in microbial structure among the groups. At the genus level, EGCG induced changes in the microbiota composition in high-fat diet-fed mice, showing a significantly higher abundance of Adlercreutzia, Akkermansia, Allobaculum and a significantly lower abundance of Desulfovibrionaceae. EGCG significantly reversed the decreased population of serum primary cholic acid and β-muricholic acid as well as the increased population of taurine-conjugated cholic acid, β-muricholic acid and deoxycholic acid in high-fat diet-fed mice. Finally, the correlation analysis between bile acid profiles and gut microbiota demonstrated the contribution of Akkermansia and Desulfovibrionaceae in the improvement of bile acid dysregulation in high-fat diet-fed mice by treatment with EGCG. In conclusion, the present study suggests that EGCG could alter bile acid metabolism, especially taurine deconjugation, and suppress fatty liver disease by improving the intestinal luminal environment.
Ursodeoxycholic acid (UDCA) is used in the treatment of cholestatic liver diseases, gallstone dissolution, and for patients with hepatitis C virus infection to ameliorate elevated alanine ...aminotransferase levels. The efficacy of UDCA treatment has been debated and the mechanisms of action in humans have still not defined. Suggested mechanisms include the improvement of bile acid transport and/or detoxification, cytoprotection, and anti‐apoptotic effects. In this review, we summarize the proposed molecular mechanisms for the action of UDCA, especially in hepatocytes, and also discuss the putative future clinical usage of this unique drug.
Overview of epidermolysis bullosa SAWAMURA, Daisuke; NAKANO, Hajime; MATSUZAKI, Yasushi
Journal of dermatology,
March 2010, Letnik:
37, Številka:
3
Journal Article
Recenzirano
Epidermolysis bullosa (EB) is classified into major types – EB simplex (EBS), junctional EB (JEB) and dystrophic EB (DEB) – on the basis of the level of tissue separation within the cutaneous ...basement membrane zone. Recent advances in research on EB have led to the identification of 10 genes responsible for EB. The Japanese Ministry of Health, Labor and Welfare has designated JEB and DEB, but not EBS, as specified diseases. However, EBS has a lethal variant and should also be registered as a specified disease. In the Third Consensus Meeting on the Diagnosis and Classification of EB held in Vienna in 2007, it was recommended that Kindler syndrome should be classified as a subtype of EB. Corrective gene therapy is the most ideal therapy for EB, but much more research is required before it can be developed and used in clinical practice. Cell‐based therapies using fibroblasts and bone marrow cells have recently attracted considerable attention.
High-fat diet (HFD)-induced alteration in the gut microbial composition, known as dysbiosis, is increasingly recognized as a major risk factor for various diseases, including colon cancer. This ...report describes a comprehensive investigation of the effect of agaro-oligosaccharides (AGO) on HFD-induced gut dysbiosis, including alterations in short-chain fatty acid contents and bile acid metabolism in mice. C57BL/6N mice were fed a control diet or HFD, with or without AGO. Terminal restriction fragment-length polymorphism (T-RFLP) analysis produced their fecal microbiota profiles. Profiles of cecal organic acids and serum bile acids were determined, respectively, using HPLC and liquid chromatography-tandem mass spectrometry systems. T-RFLP analyses showed that an HFD changed the gut microbiota significantly. Changes in the microbiota composition induced by an HFD were characterized by a decrease in the order Lactobacillales and by an increase in the Clostridium subcluster XIVa. These changes of the microbiota community generated by HFD treatment were suppressed by AGO supplementation. As supported by the data of the proportion of Lactobacillales order, the concentration of lactic acid increased in the HFD + AGO group. Data from the serum bile acid profile showed that the level of deoxycholic acid, a carcinogenic secondary bile acid produced by gut bacteria, was increased in HFD-receiving mice. The upregulation tended to be suppressed by AGO supplementation. Finally, results show that AGO supplementation suppressed the azoxymethane-induced generation of aberrant crypt foci in the colon derived from HFD-treated mice. Our results suggest that oral intake of AGO prevents HFD-induced gut dysbiosis, thereby inhibiting colon carcinogenesis.
The essential trace element zinc maintains liver functions. Liver diseases can alter overall zinc concentrations, and hypozincemia is associated with various hepatic pathologies. Modulating systemic ...zinc through dietary supplementation is potentially useful for liver diseases. We evaluated the usefulness of zinc (NPC-02; acetate formulation) supplementation. We conducted two NPC-02 studies on zinc-deficient patients (serum zinc < 70 μg/dL). Study 1: double-blind, randomized, placebo-controlled trial on 57 subjects with chronic liver diseases comparing serum zinc in patients given NPC-02 (NPC-02 group) versus placebo (Placebo group). Study 2: dose adjustment study on 43 subjects with/without liver diseases to determine proportions maintaining serum zinc target (≥ 80 μg/dL but < 200 μg/dL). In study 1, NPC-02 subjects had higher serum zinc concentrations at week 8 than Placebo subjects (83.2 ± 20.2 and 61.3 ± 12.0, respectively;
P
< 0.0001), and more NPC-02 than Placebo subjects achieved the serum zinc target (15/27 vs. 1/26). In study 2, the NPC-02-induced serum zinc increase was dose-dependent in subjects both with and without liver diseases (
r
= 0.5143,
P
= 0.0022 and
r
= 0.5753,
P
= 0.0005, respectively). Interestingly, there was a marginally positive correlation between serum zinc and albumin levels in subjects with but not in those without liver diseases (
r
= 0.4028,
P
= 0.0631 and
r
= 0.1360,
P
= 0.5567, respectively). NPC-02 dose-dependently increases serum zinc in hypozincemic patients, regardless of liver disease. NPC-02 is a potentially effective therapy for liver cirrhosis, in which zinc deficiency is common. Clinical trial registry number: NCT02337569, NCT02321865.
Abstract
Background
Dysbiosis, especially a reduced Clostridium subcluster XIVa (XIVa), has been reported in several gastrointestinal diseases. Since XIVa is thought to be the main bacterial cluster ...that metabolizes bile acids (BAs) in the human intestine, we hypothesized that the BA profile in feces, and possibly in serum, could be a convenient biomarker for intestinal XIVa activity.
Methods
First, blood and feces were collected from 26 healthy controls and 20 patients with gastrointestinal diseases, and the relationships among fecal microbiomes and fecal and serum BA compositions were studied. Second, serum BA compositions of 30 healthy controls and the remission and exacerbation states of 14 Crohn's disease (CD) and 12 ulcerative colitis (UC) patients were compared. Fecal microbiomes were analyzed by terminal restriction fragment length polymorphism analysis, and BA compositions were quantified by HPLC-MS/MS.
Results
The highest positive correlation was observed between the fecal XIVa proportion and fecal unconjugated deoxycholic acid (DCA)/(DCA+unconjugated cholic acid CA) (r = 0.77, P < 0.0001) or serum DCA/(DCA+CA) (r = 0.52, P < 0.001). Diurnal variation in serum XIVa candidate markers also showed that DCA/(DCA+CA) was most stable and not affected by the contraction of the gallbladder. Serum DCA/(DCA+CA) was not significantly different between remission and exacerbation states in either CD or UC patients, but was significantly reduced in those in the remission state of CD and the remission and exacerbation states of UC compared with healthy controls (P < 0.05).
Conclusions
Decreased XIVa exhibits a strong correlation with reduced intestinal BA metabolism. Fecal and serum DCA/(DCA+CA) could be useful surrogate markers for the intestinal proportion of XIVa.
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