lncfos/miR-212-5p/CASP7 Axis-Regulated miR-212-5p Protects the Brain Against Ischemic Damage

miR-212-5p has been reported to be involved in many biological processes. However, the role of miR-212-5p in ischemic stroke remains unclear. This study explored the biological role and potential mechanism of miR-212-5p in ischemic stroke by investigating the lncfos/miR-212-5p/CASP7 axis. A total of 32 patients with ischemic stroke and 32 age- and sex-matched healthy controls (HCs) were enrolled in this study. In addition, 336 rats were used in this study. The rats were subjected to middle cerebral artery occlusion (MCAO) and intracerebroventricular injection of a microRNA (miRNA) agomir, a miRNA antagomir, a short hairpin RNA (shRNA) lentiviral vector, or a negative control. The neurological deficit score was calculated; the infarct volume was measured; histopathological assays were performed; the neuronal apoptosis rate was determined; and the lncfos, miR-212-5p, and CASP7 expression levels in the peri-infarct area were assessed. In this study, we found that the expression level of miR-212-5p was significantly downregulated in the peri-infarct area and blood of the MCAO model rats and the blood of patients with ischemic stroke. A double-luciferase experiment showed that CASP7 was a direct target gene of miR-212-5p and that miR-212-5p was a target miRNA of lncfos. Lateral ventricular injection of the miR-212-5p agomir effectively inhibited the apoptosis induced by ischemic brain damage, reduced the infarct volume, attenuated the neurological deficit symptoms, and downregulated the expression of CASP7 in the peri-infarct area of the MCAO model rats. Suppressing lncfos with sh-fos led to the upregulated expression of miR-212-5p and played a neuroprotective role in the rat MCAO models. We concluded that miR-212-5p plays a neuroprotective role in ischemic stroke and that its function is regulated by the lncfos/miR-212-5p/CASP7 axis. Moreover, miR-212-5p may be a potential biomarker and therapeutic target for ischemic stroke.

Mucosal Profiling of Pediatric-Onset Colitis and IBD Reveals Common Pathogenics and Therapeutic Pathways

Pediatric-onset colitis and inflammatory bowel disease (IBD) have significant effects on the growth of infants and children, but the etiopathogenesis underlying disease subtypes remains incompletely understood. Here, we report single-cell clustering, immune phenotyping, and risk gene analysis for children with undifferentiated colitis, Crohn's disease, and ulcerative colitis. We demonstrate disease-specific characteristics, as well as common pathogenesis marked by impaired cyclic AMP (cAMP)-response signaling. Specifically, infiltration of PDE4B- and TNF-expressing macrophages, decreased abundance of CD39-expressing intraepithelial T cells, and platelet aggregation and release of 5-hydroxytryptamine at the colonic mucosae were common in colitis and IBD patients. Targeting these pathways by using the phosphodiesterase inhibitor dipyridamole restored immune homeostasis and improved colitis symptoms in a pilot study. In summary, comprehensive analysis of the colonic mucosae has uncovered common pathogenesis and therapeutic targets for children with colitis and IBD.

Genetic resilience to Alzheimer's disease in APOE ε4 homozygotes: A systematic review

INTRODUCTION

Individuals with homozygosity for the apolipoprotein E (APOE) ε4 allele are in the highest risk category for late-onset Alzheimer's disease (LOAD). However, some individuals in this category do not develop LOAD beyond the age of 75 years, despite being at elevated genetic risk. These "resilient" individuals may carry protective genetic factors.

METHODS

This study aimed to systematically review any previous studies that involved resilient APOE ε4 homozygotes and to identify possible modifying or protective genetic factors.

RESULTS

Fifteen studies met our inclusion criteria and reported genetic factors contributing to reduced risk. We found that only two single nucleotide polymorphisms, CASP7 rs10553596 and SERPINA3 rs4934-A/A, had strong evidence.

DISCUSSION

We found a paucity of studies adequately designed to discover protective genetic factors against LOAD. Many studies combined APOE ε4 homozygotes and heterozygotes together because of small sample sizes and used control populations too young to be clearly defined as controls for LOAD.

Emricasan Improves Liver Function in Patients With Cirrhosis and High Model for End-Stage Liver Disease Scores Compared With Placebo

BACKGROUND & AIMS

Caspase-mediated apoptosis and inflammation contribute to progression of liver disease. Emricasan is a pan-caspase inhibitor that reduced serum markers of apoptosis and liver inflammation in patients with hepatitis C and non-alcoholic steatohepatitis (NASH).

METHODS

We performed a multicenter study of 86 patients with cirrhosis (Child-Pugh class A or B; mean score, 6.9; 38% with alcohol-associated cirrhosis, 29% with HCV-associated cirrhosis, and 23% with NASH) and model for end-stage liver disease (MELD) scores of 11-18 (mean, 12.8). Patients were randomly assigned to groups given placebo (N = 42) or Emricasan (25 mg, N = 44), twice daily for 3 months; subjects then received open-label Emricasan (25 mg) twice-daily for 3 months. The primary endpoint was the change from baseline in serum levels of cleaved keratin 18 (CK-18) at month 3.

RESULTS

Seventy-four patients completed the 3-month study period (40 given Emricasan and 34 given placebo); 69 patients received open-label Emricasan for 3 months afterward. At the 3-month timepoint, Emricasan significantly reduced mean MELD (P = .003) and Child-Pugh (P = .003) scores in subjects with high MELD scores (15 or more), compared with placebo, with significant reductions in INR (95% CI, -0.2882 to -0.0866) and total bilirubin (95% CI, -1.5069 to -0.0823) vs placebo. There were no significant differences between Emricasan and placebo groups in mean MELD (P = .466) or Child-Pugh (P = .124) scores overall at 3 months compared to placebo. Of patients with high MELD scores, 6/9 given Emricasan (67%) had a reduction of 2 points or more at month 3, compared with 2/10 given placebo (20%). Serum levels of full-length CK-18 (P = .02) and caspase 3/7 (P < .001), but not cleaved CK-18 (P = .092), decreased significantly at 3 months in the Emricasan vs placebo group. Emricasan was well tolerated, and adverse events were balanced between groups. Emricasan's effects were generally maintained or increased after 6 months of treatment.

CONCLUSIONS

In a randomized trial of patients with cirrhosis, we found 3 months treatment with Emricasan to improve liver function, compared with placebo, reducing MELD and Child-Pugh scores, INR, and total bilirubin in patients with MELD scores ≥15. ClinicalTrials.gov no: NCT02230670.

A loss of function variant in CASP7 protects against Alzheimer's disease in homozygous APOE ε4 allele carriers

Background

Alzheimer’s disease (AD) represents the most common form of dementia in elder populations with approximately 30 million cases worldwide. Genome wide genotyping and sequencing studies have identified many genetic variants associated with late-onset Alzheimer’s disease (LOAD). While most of these variants are associated with increased risk of developing LOAD, only limited number of reports focused on variants that are protective against the disease.

Methods

Here we applied a novel approach to uncover protective alleles against AD by analyzing genetic and phenotypic data in Mount Sinai Biobank and Electronic Medical Record (EMR) databases.

Results

We discovered a likely loss-of-function small deletion variant in the caspase 7 (CASP7) gene associated with significantly reduced incidence of LOAD in carriers of the high-risk APOE ε4 allele. Further investigation of four independent cohorts of European ancestry revealed the protective effect of the CASP7 variant against AD is most significant in homozygous APOE ε4 allele carriers. Meta analysis of multiple datasets shows overall odds ratio = 0.45 (p = 0.004). Analysis of RNA sequencing derived gene expression data indicated the variant correlates with reduced caspase 7 expression in multiple brain tissues we examined.

Conclusions

Taken together, these results are consistent with the notion that caspase 7 plays a key role in microglial activation driving neuro-degeneration during AD pathogenesis, and may explain the underlying genetic mechanisms that anti-inflammatory interventions in AD show greater benefit in APOE ε4 carriers than non-carriers. Our findings inform potential novel therapeutic opportunities for AD and warrant further investigations.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-016-2725-z) contains supplementary material, which is available to authorized users.