CrebH protects against liver injury associated with colonic inflammation via modulation of exosomal miRNA.

BACKGROUND: Hepatic liver disease, including primary sclerosing cholangitis (PSC), is a serious extraintestinal manifestations of colonic inflammation. Cyclic adenosine monophosphate (cAMP)-responsive element-binding protein H (CrebH) is a transcription factor expressed mostly in the liver and small intestine. However, CrebH's roles in the gut-liver axis remain unknown. METHODS: Inflammatory bowel disease (IBD) and PSC disease models were established in wild-type and CrebH-/- mice treated with dextran sulfate sodium, dinitrobenzene sulfonic acid, and diethoxycarbonyl dihydrocollidine diet, respectively. RNA sequencing were conducted to investigate differential gene expression. Exosomes were isolated from plasma and culture media. miRNA expression profiling was performed using the NanoString nCounter Mouse miRNA Panel. Effects of miR-29a-3p on adhesion molecule expression were investigated in bEnd.3 brain endothelial cells. RESULTS: CrebH-/- mice exhibited accelerated liver injury without substantial differences in the gut after administration of dextran sulfate sodium (DSS), and had similar features to PSC, including enlarged bile ducts, enhanced inflammation, and aberrant MAdCAM-1 expression. Furthermore, RNA-sequencing analysis showed that differentially expressed genes in the liver of CrebH-/- mice after DSS overlapped significantly with genes changed in PSC-liver. Analysis of plasma exosome miRNA isolated from WT and CrebH-/- mice indicates that CrebH can contribute to the exosomal miRNA profile. We also identified miR-29a-3p as an effective mediator for MAdCAM-1 expression. Administration of plasma exosome from CrebH-/- mice led to prominent inflammatory signals in the liver of WT mice with inflammatory bowel disease (IBD). CONCLUSIONS: CrebH deficiency led to increased susceptibility to IBD-induced liver diseases via enhanced expression of adhesion molecules and concomitant infiltration of T lymphocytes. Exosomes can contribute to the progression of IBD-induced liver injury in CrebH-/- mice. These study provide novel insights into the role of CrebH in IBD-induced liver injury.

Molecular and epidemiological characterization of enteroviruses isolated in Chungnam, Korea from 2005 to 2006.

Enteroviruses were identified and characterized from patients with aseptic meningitis and other enterovirusrelated diseases in Chungnam, Korea from 2005 to 2006. Enteroviruses were isolated from 79 of 519 cases (15.2%) in 2005, and 37 of 386 cases (9.6%) in 2006. Based on partial VP1 sequencing, a total of 116 enterovirus isolates were resolved into 13 types. Prevalent among the Chungnam isolates were echovirus 18 and coxsackievirus B5 in 2005, and echoviruses 5 and 25 in 2006. This is the first time echoviruses 5 and 18 have been identified in Korea since enterovirus surveillance began there in 1993. The temporal distribution of enterovirus epidemics in Chungnam showed a remarkable seasonal pattern, with cases occurring during most of the three months of the summer from June to August. The highest rate of enterovirus-positive cases occurred in patients less than 1 year of age. The ratio of male to female enterovirus-positive patients was approximately 1.8:1. Comparison of the VP1 amino acid sequences of the 15 coxsackievirus B5 isolates with reference strains revealed that all Chungnam isolates are substituted at positions 23 (V23I), 19 (S19G), 75 (Y75F), and 95 (N95S). Upon comparing the nine ECV5 isolates with foreign strains, it was found that only the Chungnam isolates, with the exception of Kor06-ECV5-239cn, have P at position 153 and F at position 146. The three ECV9 isolates from 2006 show alterations at amino acids 36, 148, and 154 outside of the BC-loop and at position 84 in the BC-loop, whereas the seven isolates from 2005 and the other ECV9 strains in the database only show the alteration at position 84 (D, I, N, S). The five ECV25 isolates have an S residue at position 134, whereas most of the foreign strains have an N residue.

[Application of a diagnostic method using reverse transcription-PCR ELISA for the diagnosis of enteroviral infections].

BACKGROUND: Enteroviruses are known as major pathogen for aseptic meningitis. Although rapid diagnosis for enteroviruses is very essential to exclude bacterial infections in patients with meningitis, classical diagnostic method based on virus isolation is not practicable for timely treatment of patients due to its laborious and time-consuming procedure. Recently molecular methodologies as alternatives are routinely used for rapid and sensitive diagnosis for enteroviruses infections. METHODS: Reverse transcription (RT)-PCR ELISA kit for targeting 5' non-coding region (NCR) with highly conserved genetic identity among all genotypes of enteroviruses was introduced in this investigation. RT-PCR ELISA was evaluated about sensitivity and specificity through virus isolation using clinical specimens from patients suspected of enteroviral infections and enteroviral isolates comparing with conventional RT-PCR identifying them. RESULTS: The detection limit of the RT-PCR ELISA was up to 10-100 folds higher than virus isolation using cell culture and conventional RT-PCR. On comparison between above two methods, the detection rate of RT-PCR ELISA for clinical specimens from patients with aseptic meningitis was 7% higher than that of conventional RT-PCR targeting 5'NCR (P=0.016). CONCLUSIONS: Our results suggest that RT-PCR ELISA developed in this study could be an alternative diagnostic method for the detection of enteroviral genome with high sensitivity and specificity.

A detailed Hapmap of the Sitosterolemia locus spanning 69 kb; differences between Caucasians and African-Americans.

BACKGROUND: Sitosterolemia is an autosomal recessive disorder that maps to the sitosterolemia locus, STSL, on human chromosome 2p21. Two genes, ABCG5 and ABCG8, comprise the STSL and mutations in either cause sitosterolemia. ABCG5 and ABCG8 are thought to have evolved by gene duplication event and are arranged in a head-to-head configuration. We report here a detailed characterization of the STSL in Caucasian and African-American cohorts. METHODS: Caucasian and African-American DNA samples were genotypes for polymorphisms at the STSL locus and haplotype structures determined for this locus RESULTS: In the Caucasian population, 13 variant single nucleotide polymorphisms (SNPs) were identified and resulting in 24 different haplotypes, compared to 11 SNPs in African-Americans resulting in 40 haplotypes. Three polymorphisms in ABCG8 were unique to the Caucasian population (E238L, INT10-50 and G575R), whereas one variant (A259V) was unique to the African-American population. Allele frequencies of SNPs varied also between these populations. CONCLUSION: We confirmed that despite their close proximity to each other, significantly more variations are present in ABCG8 compared to ABCG5. Pairwise D' values showed wide ranges of variation, indicating some of the SNPs were in strong linkage disequilibrium (LD) and some were not. LD was more prevalent in Caucasians than in African-Americans, as would be expected. These data will be useful in analyzing the proposed role of STSL in processes ranging from responsiveness to cholesterol-lowering drugs to selective sterol absorption.