Browsing by Subject "Gut barrier"

Now showing 1 - 2 of 2

Einfluss der mediterranen Ernährung auf das Fettsäuremuster von Erythrozytenmembranen sowie auf Darmmikrobiota- und Darmbarriere-assoziierte Biomarker : Mechanismen und klinische Anwendungen
(2022) Seethaler, Benjamin; Bischoff, Stephan C.
Dissertation from Benjamin Seethaler: "Effect of the Mediterranean diet on the fatty acid pattern of erythrocyte membranes and on gut microbiota- and gut barrier-associated biomarkers - mechanisms and clinical applications". In summary, the results of the PhD project offer new insights into the biomedical mechanisms of action and health effects of the Mediterranean diet. Of particular importance is the relationship we have shown between dietary fiber from the Mediterranean diet, its fermentation to short-chain fatty acids, and its beneficial influence on impaired intestinal barrier function. In the future, our studies may provide the basis for personalized nutritional therapy to improve impaired gut barrier function in high-risk breast cancer patients. Furthermore, we were able to establish LBP and zonulin as biomarkers to detect gut barrier function and to determine and assess gut barrier disorders. This method validation simplifies or enables the assessment of intestinal barrier function in clinical practice or clinical trials.
Vitamin A- and D-deficient diets disrupt intestinal antimicrobial peptide defense involving Wnt and STAT5 signaling pathways in mice
(2023) Filipe Rosa, Louisa; Petersen, Patricia P.; Görtz, Lisa F.; Stolzer, Iris; Kaden-Volynets, Valentina; Günther, Claudia; Bischoff, Stephan C.
Vitamin A and D deficiencies are associated with immune modulatory effects and intestinal barrier impairment. However, the underlying mechanisms remain unclear. C57BL/6J mice were fed either a diet lacking in vitamin A (VAd), vitamin D (VDd) or a control diet (CD) for 12 weeks. Gut barrier function, antimicrobial peptide (AMP) defense and regulatory pathways were assessed. VAd mice compared to CD mice showed a reduced villus length in the ileum (p < 0.01) and decreased crypt depth in the colon (p < 0.05). In both VAd- and VDd-fed mice, ileal α-defensin 5 (p < 0.05/p < 0.0001 for VAd/VDd) and lysozyme protein levels (p < 0.001/p < 0.0001) were decreased. Moreover, mRNA expression of lysozyme (p < 0.05/p < 0.05) and total cryptdins (p < 0.001/p < 0.01) were reduced compared to controls. Furthermore, matrix metalloproteinase-7 (Mmp7) mRNA (p < 0.0001/p < 0.001) as well as components of the Wnt signaling pathway were decreased. VAd- and VDd-fed mice, compared to control mice, exhibited increased expression of pro-inflammatory markers and β-defensins in the colon. Organoid cell culture confirmed that vitamins A and D regulate AMP expression, likely through the Jak/STAT5 signaling pathway. In conclusion, our data show that vitamin A and D regulate intestinal antimicrobial peptide defense through Wnt and STAT5 signaling pathways.