Dimethyloxallyl Glycine Preconditioning Promotes the Anti-inflammatory and Anti-fibrotic Effects of Human Umbilical Cord Mesenchymal Stem Cells on Kidney Damage in Systemic Lupus Erythematosus Related to TGF-ß/Smad Signaling Pathway.

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease lacking effective treatments without adverse effects. Dimethyloxallyl glycine (DMOG) enhanced mesenchymal stem cells (MSC) capabilities, but it remains unclear how DMOG-pretreatment of MSCs augments their SLE treatment. Here, we explore the therapeutic potential of DMOG-pretreated human umbilical cord MSCs (hUC-MSCs) in a mouse lupus nephritis (LN) model. In vitro experiments showed that DMOG could alleviate the mRNA levels of tumor necrosis factor (TNF)-α, interferon (IFN)-γ, and interleukin (IL)-6 and increase the mRNA level of IL-13 in lipopolysaccharide (LPS)-induced inflammation in hUC-MSCs. DMOG enhanced the migratory and invasive abilities of the hUC-MSCs. In vivo animal studies revealed that DMOG-pretreated hUC-MSCs exhibited more pronounced inhibition of lymphadenectasis and reduced kidney weight and urinary protein content than MSCs alone. DMOG-pretreated hUC-MSCs improved renal morphological structure and alleviated inflammatory cell infiltration and renal fibrosis, evidenced by the reduced mRNA levels of fibrosis markers, including fibronectin (Fn), collagen alpha-1 chain (Colα1), collagen alpha-3 chain (Colα3), and TNF-α, IFN-γ, and IL-6 cytokines. Further investigation revealed that DMOG-pretreated hUC-MSCs down-regulated the expressions of transforming growth factor (Tgf)-ß1 and its downstream effectors Smad2 and Smad3, recognized as central mediators in renal fibrosis (P < 0.05). The findings suggest that DMOG-pretreated hUC-MSCs can augment the therapeutic efficacy of hUC-MSCs in LN by enhancing their anti-inflammatory and antifibrotic effects, and the TGF-ß/Smad signaling pathway may be involved in this process.

A defined serum-free culture system for human long-term haematopoietic stem cells.

Long-term repopulating haematopoietic stem cells (LT-HSCs) have the ability to reconstitute the entire haematopoietic system following transplantation permanently. Despite great achievements in HSC transplantation, the limited transplantable HSC number, especially LT-HSCs, remains critical for successful transplantation and broader applications. In this study, we established a defined serum-free culture system for in vitro expansion of LT-HSCs. This culture system (E1) expanded LT-HSCs from umbilical cord blood, human mobilization peripheral blood and bone marrow. These E1-expanded HSCs reconstituted the haematopoietic and immune systems in primary and secondary transplanted mice in a short time. Better haematopoietic reconstitution was observed in secondary xenografted mice. Moreover, we obtained the comprehensive expression profile and cellular components of LT-HSCs from umbilical cord blood. Our study provides a valuable tool for LT-HSC research and may improve clinical applications of HSCs.

Transplantation of umbilical cord-derived mesenchymal stem cells promotes the recovery of thin endometrium in rats.

The endometrium plays a critical role in embryo implantation and pregnancy, and a thin uterus is recognized as a key factor in embryo implantation failure. Umbilical cord mesenchymal stem cells (UC-MSCs) have attracted interest for the repair of intrauterine adhesions. The current study investigated the repair of thin endometrium in rats using the UC-MSCs and the mechanisms involved. Rats were injected with 95% ethanol to establish a model of thin endometrium. The rats were randomly divided into normal, sham, model, and UC-MSCs groups. Endometrial morphological alterations were observed by hematoxylin-eosin staining and Masson staining, and functional restoration was assessed by testing embryo implantation. The interaction between UC-MSCs and rat endometrial stromal cells (ESCs) was evaluated using a transwell 3D model and immunocytochemistry. Microarray mRNA and miRNA platforms were used for miRNA-mRNA expression profiling. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analyses were performed to identify the biological processes, molecular functions, cellular components, and pathways of endometrial injury and UC-MSCs transplantation repair and real-time quantitative reverse transcription PCR (qRT-PCR) was performed to further identify the expression changes of key molecules in the pathways. Endometrium thickness, number of glands, and the embryo implantation numbers were improved, and the degree of fibrosis was significantly alleviated by UC-MSCs treatment in the rat model of thin endometrium. In vitro cell experiments showed that UC-MSCs migrated to injured ESCs and enhanced their proliferation. miRNA microarray chip results showed that expression of 45 miRNAs was downregulated in the injured endometrium and upregulated after UC-MSCs transplantation. Likewise, expression of 39 miRNAs was upregulated in the injured endometrium and downregulated after UC-MSCs transplantation. The miRNA-mRNA interactions showed the changes in the miRNA and mRNA network during the processes of endometrial injury and repair. GO and KEGG analyses showed that the process of endometrial injury was mainly attributed to the decomposition of the extracellular matrix (ECM), protein degradation and absorption, and accompanying inflammation. The process of UC-MSCs transplantation and repair were accompanied by the reconstruction of the ECM, regulation of chemokines and inflammation, and cell proliferation and apoptosis. The key molecules involved in ECM-receptor interaction pathways were further verified by qRT-PCR. Itga1 and Thbs expression decreased in the model group and increased by UC-MSCs transplantation, while Laminin and Collagen expression increased in both the model group and MSCs group, with greater expression observed in the latter. This study showed that UC-MSCs transplantation could promote recovery of thin endometrial morphology and function. Furthermore, it revealed the expression changes of miRNA and mRNA after endometrial injury and UC-MSCs transplantation repair processed, and signaling pathways that may be involved in endometrial injury and repair.

Down-regulation of microRNA-30d-5p is associated with gestational diabetes mellitus by targeting RAB8A.

Gestational Diabetes Mellitus (GDM) is a complicated clinical process, and metabolic disorders during pregnancy are closely related to the structure and function of the placenta. The aberrant expression of miRNAs in the placenta may play a role in the occurrence and development of GDM. Analysis of microRNA (miRNA) expression signature in placenta showed that the level of miR-30d-5p was significantly down-regulated in GDM patients. This study aims to explore the possible mechanism of GDM under the regulation of miR-30d-5p. In situ hybridization and qRT-PCR assay showed that miR-30d expression down-regulated in the placentas from GDM patients compared with normal control group. The trophoblast cells proliferation and glucose uptake capacity were increased, the ability of migration and invasion were also improved after inhibiting the function of endogenous mature miR-30d-5p. Bioinformatics analysis and luciferase reporter assays showed that miR-30d-5p binds to the 3'UTR of RAB8A mRNA, resulting in RAB8A suppression. Moreover, the down-regulation of RAB8A could attenuate the increase in trophoblast cell proliferation, migration, invasion and glucose uptake induced by miR-30d-5p functional inhibitor. These data imply that miR-30d-5p expression is down-regulated in placental tissue from GDM patients and affects trophoblast cell functions by targeting RAB8A, which may provide new insight into the pathogenesis of GDM.

The polymorphism of rs11614913 T/T in pri-miR-196a-2 alters the miRNA expression and associates with recurrent spontaneous abortion in a Han-Chinese population.

Rs11614913 in pri-miR-196a-2 is involved in the occurrence of many diseases, especially in cancers. However, it remains unknown whether miR-196a-2 is associated with human recurrent spontaneous abortion (RSA) in Chinese Han population. Our study found that rs11614913 T/T in pri-miR-196a-2 was associated with the increase risk of human unexplained RSA (URSA) in recessive mode in Chinese Han population. The T allele of rs11614913 increased the production of mature miR-196a-3p. Rs11614913 T/T inhibited HTR-8/SVneo cells proliferation and migration and promoted cells apoptosis. Further investigation discovered that dihydrofolate reductase (DHFR) was the target of miR-196a-3p and inversely regulated by miR-196a-3p. Dual-luciferase assay indicated that T allele in miR-196a-2 rs11614913 could more effectively suppress DHFR expression than C allele. In addition, C to T substitution in miR-196a-2 rs11614913 attenuated the sensibility of cells to mifepristone. Collectively, our data suggest that miR-196a-2 rs11614913 T/T in pri-miR-196a-2 may be conductive to the genetic predisposition to RSA by disrupting the production of mature miR-196a-3p and reinforcing the expression of DHFR.