An Approach to Intersectionally Target Mature Enteroendocrine Cells in the Small Intestine of Mice.

Enteroendocrine cells (EECs) constitute only a small proportion of Villin-1 (Vil1)-expressing intestinal epithelial cells (IECs) of the gastrointestinal tract; yet, in sum, they build the largest endocrine organ of the body, with each of them storing and releasing a distinct set of peptides for the control of feeding behavior, glucose metabolism, and gastrointestinal motility. Like all IEC types, EECs are continuously renewed from intestinal stem cells in the crypt base and terminally differentiate into mature subtypes while moving up the crypt-villus axis. Interestingly, EECs adjust their hormonal secretion according to their migration state as EECs receive altering differentiation signals along the crypt-villus axis and thus undergo functional readaptation. Cell-specific targeting of mature EEC subtypes by specific promoters is challenging because the expression of EEC-derived peptides and their precursors is not limited to EECs but are also found in other organs, such as the brain (e.g., Cck and Sst) as well as in the pancreas (e.g., Sst and Gcg). Here, we describe an intersectional genetic approach that enables cell type-specific targeting of functionally distinct EEC subtypes by combining a newly generated Dre-recombinase expressing mouse line (Vil1-2A-DD-Dre) with multiple existing Cre-recombinase mice and mouse strains with rox and loxP sites flanked stop cassettes for transgene expression. We found that transgene expression in triple-transgenic mice is highly specific in I but not D and L cells in the terminal villi of the small intestine. The targeting of EECs only in terminal villi is due to the integration of a defective 2A separating peptide that, combined with low EEC intrinsic Vil1 expression, restricts our Vil1-2A-DD-Dre mouse line and the intersectional genetic approach described here only applicable for the investigation of mature EEC subpopulations.

NIK/MAP3K14 in hepatocytes orchestrates NASH to hepatocellular carcinoma progression via JAK2/STAT5 inhibition.

OBJECTIVE: Nonalcoholic fatty liver disease (NAFLD) ranges from steatosis to nonalcoholic steatohepatitis (NASH), which often progresses to hepatocellular carcinoma (HCC) through a largely undefined mechanism. NASH and HCC depend on inflammatory signaling, whose master regulator is the NFκB transcription factor family, activated by canonical and non-canonical pathways. METHODS: Here, we investigated non-canonical NFκB-inducing kinase (NIK/MAP3K14) in metabolic NASH, NASH to HCC transition, and DEN-induced HCC. To this end, we performed dietary and chemical interventions in mice that were analyzed via single nucleus sequencing, gene expression and histochemical methods. Ultimately, we verified our mouse results in human patient samples. RESULTS: We revealed that hepatocyte-specific NIK deficiency (NIKLKO) ameliorated metabolic NASH complications and reduced hepatocarcinogenesis, independent of its role in the NFκB pathway. Instead, hepatic NIK attenuated hepatoprotective JAK2/STAT5 signaling that is a prerequisite for NASH and NASH to HCC progression in mice and humans. CONCLUSIONS: Our data suggest NIK-mediated inhibitory JAK2 phosphorylation at serine 633 that might be amenable for future therapeutic interventions in patients.

New digital adherence devices could prevent millions of strokes from atrial fibrillation by the end of the next century.

The effectiveness and safety of a pharmacologic intervention is highly dependent on patient's capability to follow the recommended treatment regimen. Non-adherence to pharmacologic treatments is associated with worsening conditions including hospitalization and death. This is a significant burden to healthcare systems on a global scale with non-adherence rates being as high (or higher) as 50% in the first treatment year. The most common causes for non-adherence are forgetfulness, busy lifestyle or complexity and changes in therapeutic schedules. In conditions like atrial fibrillation (AFib) this leads to a drastic increase in event rates, e.g. strokes. Patients diagnosed with AFib are strongly recommended to receive anticoagulant treatments for stroke prevention. Treatments with Vitamin K antagonists or novel oral anticoagulants (NOACs) can dramatically lower the risk of ischemic strokes in the presence of AFib. Non-adherence can expose the patients to an increased stroke risk. This is especially true for NOACs, due to their short half-life. Patients have to take these medications once or twice daily for adequate stroke prevention, i.e., single non-use of the medication can already diminish or reset the anticoagulative effect. Adherence devices could help improve patient's compliance by reminder or feedback function. They have shown to be successful in a number of clinical trails. Especially, newer devices that make use of digital technologies show promising results but are not used broadly in clinical practice. Here we provide evidence for our hypothesis that newly available adherence devices might increase adherence rates and thereby reduce the number of strokes in patients with AFib.