Background Previous studies revealed that urine-derived stem cells (USCs) could promote myogenesis after the impairment of the sphincter muscles. However, the effects of exosomes secreted by USCs (USCs-Exo) were not elucidated. Exosomes are nanosized membrane vesicles secreted by the cells. They have been proved to be effective in protecting against tissue injury and therapeutic in tissue repair. USCs are ideal sources of exosomes because of the noninvasive obtaining method and self-renewal abilitiy. This study aimed to show the therapeutic effects of USCs-Exo on improving stress urinary incontinence (SUI). Methods Rat SUI models were established in this study using vaginal balloon inflation, and urodynamic and histological examination were carried out after exosome application. The proliferation and differentiation of muscle satellite cells (SCs) were evaluated using EdU, Cell Counting Kit 8, immunofluorescence staining, and Western blot analysis. mRNAs and proteins related to the activation of SCs were detected by reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis. Results After exosome injection, the urodynamic parameters significantly improved and the injured muscle tissue recovered well. The activation, proliferation, and differentiation of SCs were promoted. The phosphorylation of extracellular-regulated protein kinases (ERK) was enhanced. When ERK was inhibited, the promoting effect of USCs-Exo treatment disappeared. Conclusion The findings of this study elucidated the functional roles of USCs-Exo in satellite cell ERK phosphorylation and identified a novel agent for skeletal muscle regeneration, providing a basis for further exploring a cell-free correction for SUI. Electronic supplementary material The online version of this article (10.1186/s13287-019-1182-4) contains supplementary material, which is available to authorized users.

BackgroundPremature ovarian failure (POF) has a great impact on reproductive endocrine function in females, and it is an important cause of infertility. Previous studies have demonstrated that small extracellular vesicles (sEVs) derived from stem cells play an important role in tissue regeneration. This study aimed to investigate the therapeutic effect of sEVs derived from embryonic stem cells (ESCs-sEVs) on damaged ovaries and explore the underlying molecular mechanisms.MethodsMice POF models were established by injecting mice with cyclophosphamide and busulfan. Then, ESCs-sEVs were intravenously transplanted into POF mice. The plasma of mice was harvested at 1 and 2 weeks after treatment to analyze the levels of anti-Mullerian hormone (AMH), estradiol (E2), and follicle stimulating hormone (FSH) by ELISA. The morphology of ovaries and follicles was observed by H&E staining, and apoptosis of granulosa cells was detected by TUNEL. In vitro, EdU and CCK-8 tests were used to evaluate the proliferation of cultured granulosa cells stimulated by ESCs-sEVs. Western blotting was used to determine the expression of PI3K/AKT and apoptotic-related proteins.ResultsAfter transplantation of ESCs-sEVs, the levels of serum sex hormones recovered to normal levels. In addition, the number of follicles was significantly increased, and the number of apoptotic cells was decreased. The results in vitro revealed that ESCs-sEVs could significantly improve the proliferation rate of granulosa cells and increase the expression of phosphorylated PI3K and AKT. Meanwhile, the positive effect on proliferation and the negative effect on apoptosis observed in granulosa cells were obviously decreased when the PI3K/AKT signaling pathway was inhibited.ConclusionOur findings suggested that ESCs-sEVs could improve ovarian function by regulating the PI3K/AKT signaling pathway, which could provide a promising clinical therapy for POF.

3β-Hydroxysteroid-Δ24 reductase (DHCR24), the final enzyme of the cholesterol biosynthetic pathway, has been associated with urogenital neoplasms. However, the function of DHCR24 in endometrial cancer (EC) remains largely elusive. Here, we analyzed the expression profile of DHCR24 and the progesterone receptor (PGR) in our tissue microarray of EC (n = 258), the existing EC database in GEO (Gene Expression Omnibus), and TCGA (The Cancer Genome Atlas). We found that DHCR24 was significantly elevated in patients with EC, and that the up-regulation of DHCR24 was associated with advanced clinical stage, histological grading, vascular invasion, lymphatic metastasis, and reduced overall survival. In addition, DHCR24 expression could be induced by insulin though STAT3, which directly binds to the promoter elements of DHCR24, as demonstrated by ChIP-PCR and luciferase assays. Furthermore, genetically silencing DHCR24 inhibited the metastatic ability of endometrial cancer cells and up-regulated PGR expression, which made cells more sensitive to progestin. Taken together, we have demonstrated for the first time the crucial role of the insulin/STAT3/DHCR24/PGR axis in the progression of EC by modulating the metastasis and progesterone response, which could serve as potential therapeutic targets for the treatment of EC with progesterone receptor loss.