摘要: The beneficial effects of hair follicle stem cells in different animal models of nervous system conditions have been extensively studied. While chick embryo extract (CEE) has been used as a growth medium supplement for these stem cells, this is the first study to show the effect of CEE on them. The rat hair follicle stem cells were isolated and supplemented with 10% fetal bovine serum plus 10% CEE. The migration rate, proliferative capacity and multipotency were evaluated along with morphometric alteration and differentiation direction. The proteome analysis of CEE content identified effective factors of CEE that probably regulate fate and function of stem cells. The CEE enhances the migration rate of stem cells from explanted bulges as well as their proliferation, likely due to activation of AP-1 and translationally controlled tumour protein (TCTP) by thioredoxin found in CEE. The increased length of outgrowth may be the result of cyclic AMP response element binding protein (CREB) phosphorylation triggered by active CamKII contained in CEE. Further, CEE supplementation upregulates the expression of vascular endothelial growth factor (VEGF), brain-derived neurotrophic factor and glial cell line-derived neurotrophic factor. The elevated expression of target genes and proteins may be due to CREB, AP-1 and c-Myc activation in these stem cells. Given the increased transcript levels of neurotrophins, VEGF, and the expression of PDGFR-alpha, S100B, MBP and SOX-10 protein, it is possible that CEE promotes the fate of these stem cells towards Schwann cells.

摘要: Inflammatory bowel disease (IBD) is a chronic condition characterized by gastrointestinal tract inflammation and still lacks satisfactory treatments. Mesenchymal stromal cells (MSCs) show promising potential for treating IBD, but their therapeutic efficacy varies depending on the tissue of origin. We aim to investigate whether intestine Peyer's patch (PP)-derived MSCs have superior immunomodulatory effects on T cells and better therapeutic effects on IBD compared with bone marrow-derived MSCs. We isolated PPs-derived Nestin+ MSCs (MSCsPP) and bone marrow-derived Nestin+ MSCs (MSCsBM) from Nestin-GFP transgenic mice to explore their curative effects on murine IBD model. Moreover, we tested the effects of IL-22 knockdown and IL-22 overexpression on the therapeutic efficacy of MSCsPP and MSCsBM in murine IBD, respectively. We demonstrated that Nestin+ cells derived from murine PPs exhibit MSC-like biological characteristics. Compared with MSCsBM, MSCsPP possess enhanced immunoregulatory ability to suppress T cell proliferation and inflammatory cytokine production. Moreover, we observed that MSCsPP exhibited greater therapeutic efficacy than MSCsBM in murine IBD models. Interestingly, IL-22, which was highly expressed in MSCsPP, could alleviate the severity of the intestinal inflammation, while knockdown IL-22 of MSCsPP remarkably weakened the therapeutic effects. More importantly, IL-22 overexpressing MSCsBM could significantly improve the symptoms of murine IBD models. This study systemically demonstrated that murine MSCsPP have a prominent advantage in murine IBD treatment, partly through IL-22.

摘要: Anticancer drugs are at the frontline of cancer therapy. However, innate resistance to these drugs occurs in one-third to one-half of patients, exposing them to the side effects of these drugs with no meaningful benefit. To identify the genes and pathways that confer resistance to such therapies, we performed a genome-wide screen in haploid human embryonic stem cells (hESCs). These cells possess the advantage of having only one copy of each gene, harbour a normal karyotype, and lack any underlying point mutations. We initially show a close correlation between the potency of anticancer drugs in cancer cell lines to those in hESCs. We then exposed a genome-wide loss-of-function library of mutations in all protein-coding genes to 10 selected anticancer drugs, which represent five different mechanisms of drug therapies. The genetic screening enabled us to identify genes and pathways which can confer resistance to these drugs, demonstrating several common pathways. We validated a few of the resistance-conferring genes, demonstrating a significant shift in the effective drug concentrations to indicate a drug-specific effect to these genes. Strikingly, the p53 signalling pathway seems to induce resistance to a large array of anticancer drugs. The data shows dramatic effects of loss of p53 on resistance to many but not all drugs, calling for clinical evaluation of mutations in this gene prior to anticancer therapy.

摘要: Osteoporotic fracture is a major health problem plaguing the ageing society, and improving its treatment is an urgent challenge. How to ameliorate bone loss determines the recovery of such fractures. Extracellular vesicle (EV)-loaded hydrogel has the capacity to treat osteoporotic fractures due to its pro-osteogenic property. And balancing proliferation and maturation of osteoblast precursors (OBPs) is of great significance to avoid OBP depletion, which is lacking in current treatment. Based on osteoblastogenic miRNAs, this study aimed to explore the efficacies of the combination of hierarchical hydrogel and EVs altering functional miRNAs level in bone loss. Through bioinformatics analyses, we screened out proliferative gene-targeting miR-200b-3p and osteogenic gene-targeting miR-130b-3p. And antagomiR-200b-3p (ant-200b) enhanced OBP proliferation, and antagomiR-130b-3p (ant-130b) promoted OBP differentiation. After confirming the directional effect of Fibronectin (Fn1) on OBPs, we prepared OBP-targeting EVs. Furthermore, encapsulation of two antagomiRNAs in EVs enhanced the respective effect of ant-200b and ant-130b. Notably, hierarchically injectable hydrogel exerted an effective function in promoting the sequential delivery of EVs-200b and EVs-130b. Importantly, hierarchical hydrogel containing dual EVs effectively ameliorated bone loss. Overall, hierarchical hydrogel based on two antagomiRNAs effectively improves bone loss in vivo due to its role in promoting OBP proliferation and maturation sequentially.

摘要: Diabetes mellitus (DM) has become a serious threat to human health. Bone regeneration deficiency and nonunion caused by DM is perceived as a worldwide epidemic, with a very high socioeconomic impact on public health. Here, we find that targeted activation of retinoic acid-related orphan receptor a (RORa) by SR1078 in the early stage of bone defect repair can significantly promote in situ bone regeneration of DM rats. Bone regeneration relies on the activation of macrophage RORa in the early bone repair, but RORa of DM rats fails to upregulation as hyperglycemic inflammatory microenvironment induced IGF1-AMPK signalling deficiency. Mechanistic investigations suggest that RORa is vital for macrophage-induced migration and proliferation of bone mesenchymal stem cells (BMSCs) via a CCL3/IL-6 depending manner. In summary, our study identifies RORa expressed in macrophages during the early stage of bone defect repair is crucial for in situ bone regeneration, and offers a novel strategy for bone regeneration therapy and fracture repair in DM patients.