Exogenous intestinal alkaline phosphatase (IAP), an enzyme produced endogenously at the brush edge of the intestinal mucosa, may mitigate the increase in aberrant intestinal permeability increased during sepsis. The aim of this study was to test the efficacy of the inhibitory effect of IAP on acute intestinal inflammation and to study the molecular mechanisms underlying IAP in ameliorating intestinal permeability. We used an in vivo imaging method to evaluate disease status and the curative effect of IAP. Two Escherichia coli (E.coli) B21 strains, carrying EGFP labeled enhanced green fluorescent protein (EGFP) and RFP labeled red fluorescent protein (RFP), were constructed as tracer bacteria and were administered orally to C57/B6N mice to generate an injection peritonitis (IP) model. The IP model was established by injecting inflammatory lavage fluid. C57/B6N mice bearing the tracer bacteria were subsequently treated with (IP+IAP group), or without IAP (IP group). IAP was administered to the mice via tail vein injections. The amount of tracer bacteria in the blood, liver, and lungs at 24 h post-injection was analyzed via flow cytometry (FCM), in vivo imaging, and Western blotting. Intestinal barrier function was measured using a flux assay with the macro-molecule fluorescein isothiocyanate dextran, molecular weight 40kD, (FD40). To elucidate the molecular mechanism underlying the effects of IAP, we examined the levels of ERK phosphorylation, and the expression levels of proteins in the ERK-SP1-VEGF and ERK-Cdx-2-Claudin-2 pathways. We observed that IAP inhibited the expression of Claudin-2, a type of cation channel-forming protein, and VEGF, a cytokine that may increase intestinal permeability by reducing the levels of dephosphorylated ERK. In conclusion, exogenous IAP shows a therapeutic effect in an injection peritonitis model. This including inhibition of bacterial translocation. Moreover, we have established an imaging methodology for live-animals can effectively evaluate intestinal permeability and aberrant bacterial translocation in IP models.

This study investigated the protective effect of FK506 in podocytes and the correlation of TRPC6 with podocyte injury repair. Methods: MPC5 were cultured in vitro, parallel with the control group, an Ang II stimulation group, and an FK506 intervention group. The apoptosis rate with flow cytometry also detected TRPC6 mRNA and protein expression by RT-PCR and Western blot, and then observed the distribution of TRPC6 with indirect immunofluorescence labeling under confocal microscope. Results: The activities of podocytes significantly increased after FK506 intervention for 24 hours and 48 hours when compared with the Ang II stimulation group, and the apoptosis rate was markedly lower than that of the Ang II stimulation group, while in contrast to TRPC6 mRNA and protein expression. Conclusion: FK506 can directly act on the podocytes to inhibit Ang II-induced damage on podocyte structures and reduce the apoptosis rate of podocytes, which may be related to stabilizing TRPC6 expression and distribution in podocytes by FK506, thus maintaining the structure and function integrity of the slit diaphragm and playing a role in protecting podocytes and antiproteinuria.

Background. Xieriga-4 decoction (XRG-4) is a classic prescription Mongolian medicine that has potent diuretic and anti-inflammatory activities. However, its functional components remain unknown. Purpose. This study aimed to identify the chemical components in XRG-4 and its metabolome in vivo. Methods. An ultra-performance liquid chromatography coupled with a quadrupole time-of-flight tandem mass spectrometry based approach was proposed to systematically profile the chemicolome and metabolome of XRG-4. Result. A total of 106 constituents were identified in XRG-4. Eighty-nine components were identified in biological samples, including 78 in urine (24 prototypes and 54 metabolites), 26 in feces (19 prototypes and 7 metabolites), and 9 in plasma (5 prototypes and 4 metabolites). In other tissues, only a few compounds, including alkaloids and iridoids, were detected. Conclusion. This comprehensive investigation of the chemical and metabolic profiles of XRG-4 provides a scientific foundation for its quality control and administration of clinically-safe medication.