Long Non-Coding RNA MALAT1 Promotes Proliferation, Angiogenesis, and Immunosuppressive Properties of Mesenchymal Stem Cells by Inducing VEGF and IDO.

Mesenchymal stem cells (MSCs) play an important role in regulating angiogenesis and immune balance. The abnormal MSCs in proliferation and function were reported at maternal fetal interface in patients with pre-eclampsia (PE). Long non-coding RNA MALAT1 was known to regulate the function of trophoblast cells. However, it is not clear whether MALAT1 regulates MSCs to be related to PE. In the present study, we found that the expression of MALAT1 was significantly reduced in both umbilical cord tissues and MSCs in patients with severe PE. MALAT1 did not affect the phenotype and differentiation of MSCs. Of note, transfection with MALAT1 plasmid into MSCs drove the cell cycle into G2/M phase and inhibited cell apoptosis. The supernatants from MALAT1-overexpressed MSCs promoted the migration of MSCs, invasion of HTR-8/SVneo and tube formation of HUVEC, while si-MALAT1 had the opposite effects. Moreover, we found that MALAT1-induced VEGF mediated these effects of MALAT1 on MSCs. Furthermore, we found that MALAT1-overexpressed MSCs promoted M2 macrophage polarization and this effect was mediated by MALAT1-induced IDO expression, suggesting that MALAT1 may enhance the immunosuppressive properties of MSCs in vivo. In addition, we also investigated the factors that inhibit MALAT1 expression in PE and found that peroxide was a cause for MALAT1 downregulation. Taken together, our data demonstrate that MALAT1 is an important endogenous regulator in the proliferation, angiogenesis, and immunosuppressive properties of MSCs, suggesting it may be involved in the pathogenesis of PE. J. Cell. Biochem. 118: 2780-2791, 2017. © 2017 Wiley Periodicals, Inc.

Curcumin inhibits placental inflammation to ameliorate LPS-induced adverse pregnancy outcomes in mice via upregulation of phosphorylated Akt.

INTRODUCTION: Excessive inflammation results in adverse pregnancy outcomes, including embryonic resorption, fetal growth restriction, and preeclampsia. This study investigated whether curcumin, a highly safe anti-inflammation drug, had protective effect on lipopolysaccharide (LPS)-treated pregnant mice. METHOD: A mouse model of LPS-induced adverse pregnancy outcomes was generated by daily administering LPS from GD 13.5 to GD 16.5. Curcumin was given from GD 0.5. The effects of curcumin on maternal hypertension, proteinuria, pregnancy outcomes, as well as proinflammatory factors, chemokines, Akt, JNK, and P38 levels in placenta were examined. RESULTS: Systolic blood pressure (156.6 ± 5.056 versus 125.5 ± 3.617 mmHg; P < 0.05) and proteinuria (22.36 ± 2.22 versus 12.70 ± 1.04 mg/L; P < 0.05) were decreased in the LPS+curcumin-treated group, as compared with the LPS-treated group. Curcumin also increased the number of live pups, fetal weight, and placental weight, while it decreased fetal resorption rate. Moreover, increased placental TNF-α, IL-1ß, and IL-6 expressions in LPS-treated group were significantly suppressed after curcumin administration. Furthermore, decreased p-Akt level in placenta induced by LPS was improved by curcumin. Of note, the expression of p-Akt increased by curcumin was accompanied by the decreased chemokines MCP-1 and MIP-1 levels and fewer CD68-positive macrophages in the placenta. CONCLUSION: Curcumin inhibited the expression of proinflammatory factors and macrophage infiltration in placenta and ameliorated LPS-induced adverse pregnancy outcomes in mice by inhibiting inflammation via upregulation of phosphorylated Akt.

Gene delivery with IFN-γ-expression plasmids enhances the therapeutic effects of MSCs on DSS-induced mouse colitis.

OBJECTIVE: Interferon-γ (IFN-γ) is known to enhance the immunosuppressive properties of mesenchymal stem cells (MSCs). The aim of this study was to determine whether gene modification with IFN-γ-expression plasmids could boost the therapeutic effects of MSCs on DSS-induced colitis. METHODS: We first reconstructed pcDNA3.1-IFNγ plasmids, transfected them to human umbilical cord derived MSCs, and detected the basic characters of MSCs including immune phenotype, cell vitality, proliferation, apoptosis and cell cycle progression after transfection. Subsequently, we analyzed the inhibition effect of IFN-γ-MSCs on T cell proliferation in vitro. Finally, we induced colitis in female C57BL/6 mice by 3 % DSS treatment and evaluated the therapeutic efficacy of IFN-γ-MSCs on colitis. RESULTS: Transfection with pcDNA3.1-IFNγ did not change the basic characters of MSCs. Interestingly, IFN-γ-MSCs showed more potent immunosuppressive effects on the proliferation of T cells compared to normal MSCs. Furthermore, systemic infusion with IFN-γ-MSCs more efficiently ameliorated DSS-induced mouse colitis including colitis-related ease of body weight, increase of colon length, decrease of disease activity index, and improvement of small intestine tissues structure. In addition, IFN-γ-MSCs increased the populations of Foxp3(+) Tregs and Th2 cells both in mesenteric lymph node and spleen, upregulated indoleamine 2, 3-dioxygenase expression, and suppressed inflammatory cytokine production in mouse colon. CONCLUSIONS: Gene delivery with IFN-γ-expression plasmids enhanced the therapeutic effects of MSCs on DSS-induced mouse colitis. This study provides an effective therapeutic strategy of MSCs for inflammatory diseases.

Differential expression of microRNAs in decidua-derived mesenchymal stem cells from patients with pre-eclampsia.

BACKGROUND: Mesenchymal stem cells (MSCs) at maternal-fetal interface are considered to play an important role in the pathogenesis of pre-eclampsia (PE). microRNAs (miRNAs) also have an important influence on differentiation, maturation, and functions of MSCs. Our aim in this study was to determine the differential expression of miRNAs in decidua-derived MSCs (dMSCs) from severe PE and normal pregnancies. RESULTS: miRNA expression profiles in dMSCs from five patients with severe PE and five healthy pregnant women were screened using microarray. Then, bioinformatic analysis of the microarray results was performed. Out of 179 differentially expressed miRNAs, 49 miRNAs had significant (p < 0.05) differential expression of ≥ 2.0-fold changes, including 21 up-regulated and 28 down-regulated. miRNA-Gene-network and miRNA-Gene ontology (GO) -network analyses were performed. Overall, 21 up-regulated and 15 down-regulated miRNAs showed high degrees in these analyses. Moreover, the significantly enriched signaling pathways and GOs were identified. The analyses revealed that pathways associated with cell proliferation, angiogenesis, and immune functions were highly regulated by the differentially expressed miRNAs, including Wnt signaling pathway, mitogen-activated protein kinase signaling pathway, transforming growth factor beta signaling pathway, T-cell receptor signaling pathway, and B cell receptor signaling pathway. Four miRNA predicted target genes, vascular endothelial growth factor A (VEGFA), indoleamine 2,3-dioxygenase, suppression of cytokine signaling 3, and serine/threonine protein phosphatase 2A 55 kDa regulatory subunit B α isoform (PPP2R2A) were all decreased in dMSCs from patients with PE. Furthermore, the physiological roles of miR-16 and miR-136 in the down-regulation of VEGFA and PPP2R2A, respectively, were confirmed through reporter assays. CONCLUSIONS: These findings suggest that miRNAs in dMSCs may be important regulatory molecules in the development of PE.

Extremely low frequency magnetic fields inhibit adipogenesis of human mesenchymal stem cells.

It was reported that obese (Ob/Ob) mice lose their weight and fat when treated with 0.5 T direct current electromagnetic fields. We also observed that 7.5 Hz, 0.4 T rotation of extremely low frequency magnetic fields (ELF-MF) has an inhibitory effect on obesity. Mesenchymal stem cells (MSCs) are multi-potent cells capable of differentiating to different MSC lineages, including adipose. We hypothesized that inhibitory effects of ELF-MF on obesity may be related to the differentiation of MSCs to adipocytes. In the present study, we investigated the effects of 7.5 Hz, 0.4 T ELF-MF on differentiation of human umbilical cord MSCs. We found that ELF-MF inhibited adipogenic differentiation (exposed 2 h/day for 15 days) of MSCs but had no effect on osteogenic differentiation (exposed 2 h/day for 21 days). Moreover, ELF-MF inhibited adipocyte-specific expression of peroxisome proliferator-activated receptor 2 (PPARγ2). ELF-MF promoted c-Jun N-terminal kinase (JNK)-dependent intracellular signaling in MSCs. Furthermore, activation of the non-canonical Wnt pathway provoked the inhibition of PPARγ2 expression resulting in suppression of adipogenic differentiation. In addition, the effects of ELF-MF on growth and apoptosis of MSCs were not observed. Our data indicated that ELF-MF of 7.5 Hz, 0.4 T inhibited the adipogenic differentiation of MSCs via JNK-dependent Wnt signaling pathway, but had no effect on the growth and function of MSCs, suggesting the inhibitory effect of ELF-MF on obesity may be attributed to the inhibition of differentiation of MSCs into adipocytes. This study may provide a potential approach for the treatment of obesity.

Estrogen Promotes cAMP Production in Mesenchymal Stem Cells by Regulating ADCY2.

BACKGROUND AND OBJECTIVES: The maternal-fetal interface is an important source of mesenchymal stem cells (MSCs), and it is influenced by high levels of estradiol (E2) during pregnancy. It is highly important to study the role of E2 in MSCs for both clinical application and understanding of the mechanisms underlying pregnancy related diseases. METHODS AND RESULTS: In this study, differently expressed genes (DEGs) were found in the MSCs after exposure to E2. Then, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of DEGs was performed and the integrated regulatory network of DEGs-miRNA was constructed. A total of 390 DEGs were found in the MSCs exposed to E2, including 164 upregulated DEGs (e.g. ADCY2, VEGFA and PPY) and 226 downregulated DEGs (e.g. KNG1, AGT and NPY). Additionally, 10 miRNAs (such as miR-148A/B, miR-152, miR-182) identified the integrated regulatory network of DEGs-miRNAs. Among them, the expression of ADCY2 was significantly upregulated, and this was associated with multiple changed genes. We confirmed that the expression of ADCY2 is significantly promoted by E2 and subsequently promoted the production of cAMP in MSCs. We also found that E2 promoted ADCY2 expression by inhibiting miR-152 and miR-148a. CONCLUSIONS: E2 promotes the expression of cAMP through miR-148a/152-ADCY2 in MSCs. It is suggested that E2 plays a key role in the growth and function of MSCs.

TGF-ß3-induced miR-494 inhibits macrophage polarization via suppressing PGE2 secretion in mesenchymal stem cells.

Abnormal macrophage polarization at the maternal-fetal interface may contribute to the development of Preeclampsia (PE). The reason why macrophage polarization changed in PE is still unclear. Decidual mesenchymal stem cells (dMSCs) could regulate macrophage polarization. However, miRNA in dMSCs of PE were maladjusted. Therefore, we speculated that miRNA may affect dMSC-regulated macrophage polarization. In this study, we found that miR-494-overexpressed dMSCs inhibit M2 macrophage polarization and this inhibitory effect is mediated by miR-494-reduced PGE2 secretion. Furthermore, we proved that miR-494 is induced by TGF-ß3. In summary, our findings suggest that the high expression of TGF-ß3 in PE decidua stimulates miR-494 in dMSCs and attenuates the regulation of MSC switching the macrophage toward M2 type, contributing to an immune imbalance at maternal-fetal interface.

MiR-30a attenuates immunosuppressive functions of IL-1ß-elicited mesenchymal stem cells via targeting TAB3.

Mesenchymal stem cells (MSCs) possess the ability to modulate the immune response, and their abnormalities are related to several diseases. We previously reported that miR-30a expression significantly increased in the maternal-fetal interface during preeclampsia (PE), but the effects of miR-30a on the immunoregulatory characteristics of MSCs are unclear. In this study, we determined that miR-30a over-expression inhibited the IL-1ß-elicited activation of the nuclear factor κB (NF-κB) and JNK signaling pathways and the production of IL-6, cyclooxygenase 2 (COX2) and IL-8 by targeting transforming growth factor-ß-activated kinase 1 binding protein 3 (TAB3) in MSCs. Moreover, the over-expression of miR-30a also impaired MSCs' anti-inflammatory effects on macrophages. These data demonstrated that miR-30a in MSCs may participate in the immune dysregulation of the maternal-fetal interface during PE.

MicroRNA-494 inhibits the growth and angiogenesis-regulating potential of mesenchymal stem cells.

Mesenchymal stem cells (MSCs) play an important role in the pathology of preeclampsia (PE). Our previous microarray analysis found that microRNA-494 (miR-494) is highly expressed in decidua-derived MSCs (dMSCs) from PE. We hypothesized that aberrant expression of miR-494 in dMSCs is involved in PE development. In the present study, we found that miR-494 arrests G1/S transition in dMSCs by targeting CDK6 and CCND1. We also found that supernatant from miR-494-overexpressing dMSCs reduces HTR-8/SVneo migration and impairs HUVEC capillary formation by suppressing VEGF. Taken together, we report an unrecognized mechanism of miR-494 affecting dMSC proliferation and function in the pathology of PE.