Jujuboside A inhibits oxidative stress damage and enhances immunomodulatory capacity of human umbilical cord mesenchymal stem cells through up-regulating IDO expression / 中国天然药物

Impaired immunomodulatory capacity and oxidative stress are the key factors limiting the effectiveness of mesenchymal stem cell transplantation therapy. The present study was aimed to investigate the effects of jujuboside A (JuA) on the protective effect and immunomodulatory capacity of human umbilical cord mesenchymal stem cells (hUC-MSCs). Hydrogen peroxide was used to establish an oxidative damage model of hUC-MSCs, while PBMCs isolated from rats were used to evaluate the effect of JuA pre-treatment on the immunomodulatory capacity of hUC-MSCs. Furthermore, Hoechst 33258 staining, lactate dehydrogenase test, measurement of malondialdehyde, Western blot, high-performance liquid chromatography; and flow cytometry were performed. Our results indicated that JuA (25 μmol·L-1) promoted the proliferation of hUC-MSCs, but did not affect the differentiating capability of these cells. JuA pre-treatment inhibited apoptosis, prevented oxidative damage, and up-regulated the protein expression of nuclear factor-erythroid factor 2-related factor 2 and heme oxygenase 1 in hUC-MSCs in which oxidative stress was induced with H2O2. In addition, JuA pre-treatment enhanced the inhibitory effect of hUC-MSCs against abnormally activated PBMCs, which was related to stimulation of the expression and activity of indoleamine 2,3-dioxygenase. In conclusion, our results demonstrate that JuA pre-treatment can enhance the survival and immunomodulatory ability through pathways related to oxidative stress, providing a new option for the improvement of hUC-MSCs in the clinical setting.

Effects of Selenium on Fusarium Growth and Associated Fermentation Products and the Relationship with Chondrocyte Viability / 生物医学与环境科学（英文）

This study determined the effects of selenium on the growth of Fusarium strains and the effects of products extracted from the fungal cultures on relevant indicators of chondrocytes injury. The results showed that selenium supplementation resulted in differential effects on the mycelial growth of the strains. Levels of the chondrocyte injury indicators, including cell viability, proteoglycan and type II collagen contents and their mRNA expressions, were all reduced to varying degrees when the chondrocytes were incubated with fermentation extracts, the inhibitory effect varied depending on selenium content supplemented to fungal culture media. The results indicated that certain chain relations existed between the content of selenium in the environment, the production of some metabolites by fungi, and the occurrence of chondrocyte damage. The extent of this relationship and the role it plays in Kaschin-Beck disease pathogenesis merit further study.