RESUMEN
Kidney is an essential organ in human body with multiple physiological functions. However, there is 10 % population worldwide with renal disease. It is urgent to generate a model which is more similar with kidney at structural and functional level to study renal disease. The rise of in vitro differentiation technology from pluripotent stem cells gives regeneration medicine and precise medicine new energy. This study mimics kidney development in vitro by inducing human pluripotent stem cells including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) into kidney progenitor cells, and further forming nephrons, which is the structure and function unit in kidney. Human pluripotent stem cells were differentiated into primitive streak through activating WNT pathway while inhibiting TGF-(B signaling. Afterward, the primitive streak spontaneously differentiated into intermediate mesoderm. Then, we induced intermediate mesoderm cells into kidney progenitor cells through FGF pathway. The FACS analysis data indicated kidney progenitor cells were up to 51. 5%-61. 9% in total cell population. Immuno-stai-ning results showed these structures contained podocytes of glomerulus, proximal tubule, and distal tubule. This kidney differentiation protocol is stable, high-efficient, and well repeatable. This research provides a novel platform for early human kidney development study, kidney disease modeling, and drug screening.
RESUMEN
To study the role of oleanolic acid on interleukin (IL)-1β-stimulated expression of inflammatory cytokines, and to explore its anti-inflammatory mechanism in SW982 cells, the toxicity of oleanolic acid on SW982 cells was detected by MTT; effects of different concentrations of oleanolic acid (5, 10, 20 μmol·L-1) on the expression of inflammatory factors IL-6, IL-8 and matrix metalloproteinase-1 (MMP-1) was tested at protein and mRNA levels. The study was performed in IL-1β-stimulated SW982 cells together with enzyme-linked immunosorbent assay (ELISA) and real-time fluorescence quantitative PCR (real-time PCR) methods; the influence of oleanolic acid on the phosphorylation of mitogen-activated protein kinase (MAPK), phosphatidyl inositol-3-kinase/Akt (PI3K/Akt) and nuclear transcription factor-κB (NF-κB) signaling pathways related protein was analyzed by Western blot. Results showed that different concentrations of oleanolic acid (≤ 40 μmol·L-1) were almost non-toxicity to SW982 cells; oleanolic acid significantly inhibited the expression of inflammatory factors in a dose-dependent manner; oleanolic acid restrained extracellular signal-related kinase (ERK), p38, c-jun N-terminal kinase (JNK) and Akt protein phosphorylation and IκB-α protein degradation obviously. The inhibition effect of oleanolic acid on inflammatory factors stimulated by IL-1β may be worked through MAPK, PI3K/Akt and NF-κB signaling pathways.