Mesenchymal stem cell transplantation worsens intestinal inflammation and microenvironment in PI3Kγ-knockout mice.

Considering the possible interaction between mesenchymal stem cells (MSCs) and PI3Kγ-associated drugs, we evaluated the efficacy and action mechanism of MSCs in the treatment of colitis in PI3Kγ-/- mice. Trinitro-benzene-sulfonic acid enema was used to create a colitis model, and MSCs were transplanted through the caudal vein to treat colitis in wild-type and PI3Kγ-/- mice. We sequenced microbial 16S rRNA genes in the colonic mucosa of PI3Kγ-/- and wild-type mice and quantified colonic IgA, IL-2, IL-10, IL-17A, occludin, and serum IgA. MSC transplantation led to a more serious reduction in the weight of trinitro-benzene-sulfonic acid-administered PI3Kγ-/- mice than that in wild-type mice. The disease activity index, pathological scoring, number of taxa in the colon, Berger-Parker index, I-index, proportion of Proteobacteria, and IgA level in the blood were higher in PI3Kγ-/- mice than in wild-type mice after MSC transplantation. The occludin and IL-10 levels in the colon tissues decreased before and after MSC transplantation in PI3Kγ-/- mice, whereas they were increased in wild-type mice The IL-17 level decreased in both wild-type and PI3Kγ-/- mice, with knockout mice showing a greater decrease. Therefore, MSC transplantation in PI3Kγ-/- mice led to increased numbers of exogenous pathogenic microorganisms and enhanced colitis that was difficult to relieve.

Study on the therapeutic effects of hyperbaric oxygen on human umbilical cord Wharton jelly mesenchyme cells on myocardial infarction rats / 中国医师杂志

Objective To explore whether hyperbaric oxygen could enhance the effects of the transplanted stem cell on treating myocardial infarction rats.Methods A total of 70 Sprague-Dawley (SD) Rats was randomly divided into four groups,sham operated,acute myocardial infarction (AMI),mesenchymal stem cells (MSCs) (Stem Cell Transplanting),and hyperbaric oxygen (HBO) + MSCs group,respectively.Myocardial infarction rat model was established,hyperbaric oxygen treatment was carried out every day at the first to 30 day after AMI.Human umbilical cord Wharton jelly mesenchyme cell was transplanted at the third day after AMI.The densities of polymorphonuclear neutrophils and macrophages in the infracted border zones and in the infarcted area of heart were determined with hematoxylin and eosin (HE) staining.The cardiac function was assessed with M-mode transthoracic echocardiography,in vivo.Results (1)Compared to MSCs group,the stem cell proliferation and survival rates were increased significantly at the forth week (276.6 ±73.8 versus 20.5 ± 12.3,P ＜0.01).(2)Compared to the AMI and MSCs groups,the infracted area and the number of inflammatory cell infiltration were significantly reduced in HBO alone and MSCs + HBO groups.(3) Compared to the AMI group,the cardiac function was significantly improved at the different degree in the other three groups;among these groups,cardiac function was significantly improved in the MSCs + HBO group (P ＜0.01),except for the volume of end-dilation (P ＞0.05).Conclusions Hyperbaric oxygenation could significantly promote the proliferation and survival rate of stem cells,and improve the cardiac function.Thus further enhance the effect of the transplanted stem cell on treating the infarcted heart.