Mechanism of miR-26a-5p/cAMP response element binding protein 1 molecular axis regulating osteogenic differentiation of adipose-derived mesenchymal stem cells / 中国修复重建外科杂志

OBJECTIVE@#To investigate the regulatory effects of miR-26a-5p on the osteogenic differentiation of adipose-derived mesenchymal stem cells (ADSCs) by regulating cAMP response element binding protein 1 (CREB1).@*METHODS@#The adipose tissues of four 3-4 weeks old female C57BL/6 mice were collected and the cells were isolated and cultured by digestion separation method. After morphological observation and identification by flow cytometry, the 3rd-generation cells were subjected to osteogenic differentiation induction. At 0, 3, 7, and 14 days after osteogenic differentiation induction, the calcium deposition was observed by alizarin red staining, ALP activity was detected, miR- 26a-5p and CREB1 mRNA expressions were examined by real-time fluorescence quantitative PCR, and CREB1 protein and its phosphorylation (phospho-CREB1, p-CREB1) level were measured by Western blot. After the binding sites between miR-26a-5p and CREB1 was predicted by the starBase database, HEK-293T cells were used to conduct a dual-luciferase reporter gene experiment to verify the targeting relationship (represented as luciferase activity after 48 hours of culture). Finally, miR-26a-p inhibitor (experimental group) and the corresponding negative control (control group) were transfected into ADSCs. Alizarin red staining, ALP activity, real-time fluorescent quantitative PCR (miR-26a-5p) and Western blot [CREB1, p-CREB1, Runt-related transcription factor 2 (RUNX2), and osteocalcin (OCN)] were performed at 7 and 14 days after osteogenic induction culture.@*RESULTS@#The cultured cells were identified as ADSCs. With the prolongation of osteogenic induction culture, the number of calcified nodules and ALP activity significantly increased ( P<0.05). The relative expression of miR-26a-5p in the cells gradually decreased, while the relative expressions of CREB1 mRNA and protein, as well as the relative expression of p-CREB1 protein were increased. The differences were significant between 7, 14 days and 0 day ( P<0.05). There was no significant difference in p-CREB1/CREB1 between different time points ( P>0.05). The starBase database predicted that miR-26a-5p and CREB1 had targeted binding sequences, and the dual-luciferase reporter gene experiment revealed that overexpression of miR-26a-5p significantly suppressed CREB1 wild-type luciferase activity ( P<0.05). After 7 and 14 days of osteogenic induction, compared with the control group, the number of calcified nodules, ALP activity, and relative expressions of CREB1, p-CREB1, OCN, and RUNX2 proteins in the experimental group significantly increased ( P<0.05). There was no significant difference in p-CREB1/CREB1 between the two groups ( P>0.05).@*CONCLUSION@#Knocking down miR-26a-5p promoted the osteogenic differentiation of ADSCs by up-regulating CREB1 and its phosphorylation.

Improving the production of human placental chorionic-derived mesenchymal stem cells by modified primary culture method / 国际生物医学工程杂志

Objective To establish a cultivating method for obtaining a large number of P0 generation human placental chorionic-derived mesenchymal stem cells (hpcMSCs).Methods The hpcMSCs were isolated from human placental chorion.After primary culturing and culturing for seven days,the culture medium,the non-adherent tissue and the douching normal saline of the primary culture were centrifuged and re-cultured twice.Cell morphology was observed by an inverted microscope.CCK-8 was used to measure the cell growth curve.Flow cytometry was used to detect cell surface markers.Adipogenic and osteogenic differentiation kits were used to assess the cell differentiation potential.Results The obtained hpcMSCs were fibroblast-like adherent cells and (25.54±3.38)×106 cells were obtained per placenta.The total yield of the primary culture,secondary culture and tertiary culture were (11.73±2.09)×106,(11.12±1.42)×106 and (2.69±0.71)×106,respectively,and the incubation time were (12.00±0.64) d,(8.87±0.63) d and (12.33±0.80) d.There was significant differences in incubation time between the secondary culture and the primary culture as well as the tertiary culture (all P＜0.05),and there was no significant difference between the primary culture and the tertiary culture.However,the incubation time of the tertiary culture had an increasing trend (P＞0.05).The yield per culture flask of the primary culture,secondary culture and tertiary culture were (1.12±0.15) × 106,(2.10±0.16)×106 and (1.04±0.16)×106,respectively.There was significant differences in the yield per culture flask between the secondary culture and the primary culture as well as the tertiary culture (all P＜0.05),and there was no significant difference between the primary culture and the tertiary culture.However,the yield per culture flask of the tertiary culture had a decreasing trend (P＞0.05).There was no difference among the three cultures in the growth curve and the expression of surface markers,and the osteogenic and adipogenic differentiation were all positive.Conclusions The P0 generation hpcMSCs isolated from a choriocarcinoma sample can be doubled by the three cultures compared with the primary culture,which can provide plenty stem cell source for the regenerative medicine.

Application of Mesenchymal Stem Cells in Rhinologic Fields / 대한이비인후과학회지

Mesenchymal stem cells (MSCs) are adult stem cells which are present in a variety of adult tissues and reside in essentially all post-natal organs and tissues. MSCs represent an important stem cell population with multi-potent capabilities which may have high utility for translational clinical applications. MSCs can be isolated from a number of adult tissues and differentiate into several mesenchymal lineages both in vitro and in vivo, such as bone, cartilage, adipose tissue, and muscle. Because of their capacities of differentiation, MSCs have emerged as a promising source for therapeutic applications in tissue engineering and regenerative medicine. In addition to their multi-lineage potential, MSCs have been shown to possess the unique ability to suppress immune response and modulate inflammation. MSCs can inhibit natural killer cell function, modulate dendritic cell maturation, and suppress the allogeneic T-cell response by alternating the cytokine secretion profile of dendritic cells and T-cells induced by an allogeneic immune reaction. Therefore, MSCs have been reported to have anti-inflammatory and immunomodulatory effects in a variety of chronic inflammatory diseases. In this article, I review recent experimental data and discuss about the application of MSCs in rhinologic fields.