Objectives:The loss of enteric neurons has been shown to be a major cause of slow transit constipation (STC). Gut microbiota and muscularis macrophages (MMs) are associated with the enteric nervous system (ENS) development and gastrointestinal (GI) motility. This study aimed to investigate whether Dioscin (DIO) increased GI motility and inhibited neuron loss by modulating gut microbiota profile, improving inflammation in the ENS microenvironment.Materials and Methods:The STC model was established by loperamide. The alteration of the gut microbiota was analyzed by 16S rDNA sequencing. The longitudinal muscle and myenteric plexus (LMMP) from the colon were prepared for flow cytometry, immunofluorescence, western blot, and qRT-PCR.Results:DIO increased the stool number, stool water content and shortened whole gut transit time, helped to recover the gut microbial diversity and microbiota community structure, and increased the abundance of Muribaculaceae in STC mice. Compared with the STC group, the number of MMs and the level of the iNOS, IL-6, and TNFα genes were significantly decreased following DIO treatment. Moreover, DIO may increase the number of HuC/D+ neurons per ganglion by up-regulating the BMP2 secreted by MMs and activating the BMP2/p-Smad1/5/9 signaling pathway. Furthermore, the level of excitatory neurotransmitter AchE in colon tissues exhibited a substantial increase in the DIO group. However, the level of inhibitory neurotransmitter VIP was markedly decreased.Conclusion:Our results provide that DIO increases GI motility and inhibits neuron loss by modulating gut microbiota profile, improving inflammation in the ENS microenvironment and up-regulating the BMP2 secreted by MMs.

BACKGROUND:Ischemia reperfusion injury (IRI) is the major cause of intestinal damage in clinic. Although either mesenchymal stromal cells (MSCs) or interleukin 37 (IL-37) shows some beneficial roles to ameliorate IRI, their effects are limited. In this study, the preventative effects of IL-37 gene-modified MSCs (IL-37-MSCs) on intestinal IRI are investigated.METHODS:Intestinal IRI model was established by occluding the superior mesenteric artery for 30 minutes and then reperfused for 72 hours in rats. Forty adult male Sprague-Dawley rats were randomly divided into the sham control, IL-37-MSC-treated, MSC-treated, recombinant IL-37- (rIL-37-) treated, and untreated groups. Intestinal damage was assessed by H&E staining. The levels of gut barrier function factors (diamine oxidase and D-Lactate) and inflammation cytokine IL-1β were assayed using ELISA. The synthesis of tissue damage-related NLRP3 inflammasome and downstream cascade reactions including cleaved caspase-1, IL-1β, and IL-18 was detected by western blot. The mRNA levels of proinflammatory mediators IL-6 and TNF-α, which are downstream of IL-1β and IL-18, were determined by qPCR. Data were analyzed by one-way analysis of variance (ANOVA) after the normality test and followed by post hoc analysis with the least significant difference (LSD) test.RESULTS:IL-37-MSCs were able to migrate to the damaged tissue and significantly inhibit intestinal IRI. As compared with MSCs or the rIL-37 monotherapy group, IL-37-MSC treatment both improved gut barrier function and decreased local and systemic inflammation cytokine IL-1β level in IRI rats. In addition, tissue damage-related NLRP3 and downstream targets (cleaved caspase-1, IL-1β, and IL-18) were significantly decreased in IRI rats treated with IL-37-MSCs. Furthermore, IL-1β- and IL-18-related proinflammatory mediator IL-6 and TNF-α mRNA expressions were all significantly decreased in IRI rats treated with IL-37-MSCs.CONCLUSION:The results suggest that IL-37 gene modification significantly enhances the protective effects of MSCs against intestinal IRI. In addition, NLRP3-related signaling pathways could be associated with IL-37-MSC-mediated protection.

The study aimed to identify key genes involved in cerebral vasospasm (CVS) after subarachnoid haemorrhage (SAH). GSE46696 of basilar arteries of SAH mice and normal controls were downloaded from the Gene Expression Omnibus (GEO). Integrated microarray analysis was performed to identify differentially expressed genes (DEGs). GO and KEGG pathway enrichment analyses of DEGs were performed with ClueGO. The protein–protein interaction (PPI) networks were constructed using Cytoscape software. A total of 4103 DEGs were identified; among them, 254 DEGs (63 up-regulated genes and 191 down-regulated genes) showed significant differences at p < 0.05. GO analysis showed that the identified DEGs were over-represented in 16 GO terms. KEGG pathway analysis showed that pathways in immune inflammation were significantly enriched pathways for DEGs. DEGs with relatively frequent interactions after CVS secondary to SAH included MIKI, Cmpk2, TIr3, Psmb9, Ddx58, Lgals9, Ifi44, Stat2, Rsad2, Oas2, Usp18, H28, Irf7 and als3bp. Multiple genes were involved in the regulation of the immune response in the pathogenesis of SAH, including Ripk3, Ifih1, IL10, Reg3g, SIc11a1, NF-κB, Tlr7, Parp9, Rab7b, Dhx58, Gpx2, Zbp1, Aim2, Rsad2, Lgals9, TLR4, Adar, Zc3hav1, KIrk1, Irf7, IL-1β, Trafd1, Ddx58 and Trim5. Our findings revealed the gene expression profiles of the cerebral arteries in SAH mouse models, and speculated that DHx58 gene plays an important role in the immune response through regulating inflammatory cytokines expression, which may be a potential target in the treatment of CVS after SAH. Our finding provided new clues for understanding the mechanism of SAH.

INTRODUCTION:Many studies have reported increased intimal thickness around the catheter tip after catheterization. Caveolin-1 is a protein in the endothelial cell that acts as a shear sensor causing vascular remodeling. This study aimed to elucidate the suitability of different catheter locations and determine the role of caveolin-1 in canine models.MATERIALS AND METHODS:Tunneled silicone 14.5-F catheters were inserted into the left jugular vein and right femoral vein in 8 dogs. The dogs were separated into 2 groups by catheter location and were followed up for 28 days. All dogs underwent extracorporeal circulation 3 times a week. After animal sacrifice, histological and immunohistochemical assays were performed to measure specific cell populations.RESULTS:There were higher catheter dysfunction rates and lower blood flow rates in the right femoral vein group compared to the left jugular vein group. There was intimal hyperplasia around the catheter tip in both groups with no significant difference between the two groups. There were caveolin-1 expression in the intimal layer of venous wall around the catheter tip location sites in both groups.CONCLUSIONS:These findings indicate that different catheter tip locations may influence catheter function and specific targeting of caveonlin-1 could be a strategy of possible future novel therapies for catheter-related vein stenosis.