1.Define of Optimal Addition Period of Osteogenic Peptide to Accelerate the Osteogenic Differentiation of Human Pluripotent Stem Cells
Yameng SONG ; Hongjiao LI ; Zixuan WANG ; Jiamin SHI ; Jing LI ; Lu WANG ; Lingzi LIAO ; Shengqin MA ; Yun ZHANG ; Bin LIU ; Yaling YANG ; Ping ZHOU
Tissue Engineering and Regenerative Medicine 2024;21(2):291-308
BACKGROUND:
The addition of growth factiors is commonly applied to improve the osteogenic differentiation of stem cells. However, for human pluripotent stem cells (hPSCs), their complex differentiation processes result in the unknown effect at different stages. In this study, we focused on the widely used bone forming peptide-1 (BFP-1) and investigated the effect and mechanisms of its addition on the osteogenic induction of hPSCs as a function of the supplementation period.
METHODS:
Monolayer-cultured hPSCs were cultured in osteogenic induction medium for 28 days, and the effect of BFP-1 peptide addition at varying weeks was examined. After differentiation for varying days (0, 7, 14, 21 and 28), the differentiation efficiency was determined by RT–PCR, flow cytometry, immunofluorescence, and alizarin red staining assays. Moreover, the expression of marker genes related to germ layers and epithelial-mesenchymal transition (EMT) was investigated at day 7.
RESULTS:
Peptide treatment during the first week promoted the generation of mesoderm cells and mesenchymal-like cells from hiPSCs. Then, the upregulated expression of osteogenesis marker genes/proteins was detected in both hESCs and hiPSCs during subsequent inductions with BFP-1 peptide treatment. Fortunately, further experimental design confirmed that treating the BFP-1 peptide during 7–21 days showed even better performance for hESCs but was ineffective for hiPSCs.
CONCLUSION
The differentiation efficiency of cells could be improved by determining the optimal treatment period.Our study has great value in maximizing the differentiation of hPSCs by adding osteogenesis peptides based on the revealed mechanisms and promoting the application of hPSCs in bone tissue regeneration.
2.Correlation of fibroblast growth factor 23 with insulin resistance and sex hormone levels in patients with polycystic ovary syndrome
Yu LI ; Zixuan TANG ; Qi HUANG ; Xiaoying YUAN ; Qian WANG ; Lin ZHANG ; Han ZHANG ; Ying ZHANG ; Yachao BA ; Dingyan LUO ; Jiaoyang FENG ; Xin LIAO
Chinese Journal of Endocrinology and Metabolism 2024;40(6):475-480
Objective:To investigate the association of serum fibroblast growth factor 23(FGF23) level with insulin resistance(IR) and sex hormone levels in patients with polycystic ovary syndrome(PCOS).Methods:A retrospective study was performed in eighty-seven patients with PCOS, fifty-seven patients with simple IR, and sixty-one healthy women who were admitted to Affiliated Hospital of Zunyi Medical University during October 2021 and November 2022. According to the homeostasis model assessment-IR index, all subjects were divided into normal control group( n=61), IR group( n=57), PCOS without IR group(PCOS group, n=15), and PCOS+ IR group( n=72). The levels of serum FGF23, adiponectin, and sex hormones in all groups were compared, and their correlations with glucose and lipid metabolism indicators were analyzed. Results:The FGF23 level was significantly elevated in the IR group, while markedly reduced in the PCOS group and PCOS+ IR group, with the PCOS group showing a significantly lower concentration. The adiponectin levels were significantly decreased in the IR group, PCOS group, and PCOS+ IR group(all P<0.05). The correlation analysis showed that FGF23 level was positively correlated with adiponectin and sex hormone binding globulin, and negatively correlated with luteinizing hormone, luteinizing hormone/follicle stimulating hormone, and free testosterone index(all P<0.05). Logistic regression results indicated that both FGF23 and adiponectin could be used as good indicators for the diagnosis of PCOS and PCOS with IR(all P<0.05). Conclusion:FGF23 is closely related to IR and androgen as well, and under certain conditions, it can reflect the severity of IR and hyperandrogenemia in PCOS patients. The cutoff value of FGF23 obtained in this study can provide a good reference for the diagnosis of PCOS diseases.
3.Advances in color stability of resin cements and its influence on all-ceramics restorations
Zixuan LIAO ; Wei ZHOU ; Ling ZHANG ; Biying QIU ; Haohan YU ; Lina NIU ; Jihua CHEN
Chinese Journal of Stomatology 2021;56(2):216-220
Resin cements have been widely employed for bonding all-ceramic restorations in clinical practice, its color stability is directly related to long-term prosthetic effect of restorations. Discoloration of resin cements can be attributed to two causes: endogenous factors are generally related to material compositions and initiation mechanism of polymerization; exogenous factors are mainly related to stimulation of local oral environment. Color stability of resin cements has close relationship with esthetic effect of all-ceramic restorations. The aim of this literature review was to make a presentation and discussion systematically about color stability of resin cements commonly used clinically, its influence factors and influence on all-ceramic restorations, so as to provide a reference for the application of all-ceramic restorations.
4.Inflammatory periodontal stem cells mediate interleukin-1β secretion of macrophage by regulating macrophage endoplasmic reticulum stress
Yang ZHANG ; Yazheng WANG ; Dongdong FEI ; Xige ZHANG ; Zixuan LIAO ; Lingxia LIU ; Qintao WANG
Chinese Journal of Stomatology 2021;56(4):329-334
Objective:To investigate the effect and mechanism of periodontal ligament stem cell (PDLSC) from inflammatory environment on the secretion of interleukin-1β (IL-1β) by macrophages.Methods:PDLSCs were pretreated with lipopolysaccharide (LPS) in order to simulate the inflammatory environment. Human monocyte cell line (THP-1) cells were treated with conditioned media collected from healthy and inflammatory PDLSCs respectively and divided into conditioned medium of health PDLSC (CM-H) group and conditioned medium of LPS-PDLSC (CM-LPS) group. After 24 h of co-culture, the condition media were abandoned and THP-1 cells were then cultured for another 24 h. The expression of IL-1β in THP-1 cells supernatant was detected by enzyme-linked immunosorbent assay (ELISA). Quantitative real time-PCR (qRT-PCR) was used to detect the expression of glucose regulated protein 78 (GRP78), activating transcription factor-6 (ATF6), inositol requiring enzyme 1 (IRE1), protein kinase R-like endoplasmic reticulum kinase (PERK), CCAAT enhancer binding protein homologous protein (CHOP), activating transcription factor-4 (ATF4) and X box binding protein 1 spliced (XBP1s), which were all related with endoplasmic reticulum stress (ERS), in THP-1 cells. The expressions of proteins GRP78 and CHOP were detected by Western blotting. Furthermore, THP-1 cells, which pretreated with ER inhibitor 4-phenylbutyrate (4-PBA) for intervention experiments were grouped by various concentrations of 4-PBA including groups 0 (control group), 1, 10 and 20 mmol/L and treated with condition medium of inflammatory PDLSC. ELISA was used to detect IL-1β expression and qRT-PCR to detect expression of ERS related genes.Results:ELISA results showed that the expression of IL-1β in THP-1 cells of group CM-LPS [(31.35±2.11) ng/L] was significantly higher than group CM-H [(8.19±1.51) ng/L] ( t=12.60, P<0.01). qRT-PCR results showed that the relative expressions of GRP78, ATF6, IRE1, PERK, CHOP, ATF4 and XBP1s genes in THP-1 cells of group CM-LPS (1.782±0.070, 1.387±0.204, 1.404±0.119, 1.777±0.187, 1.325±0.156, 1.295±0.066 and 1.137±0.149, respectively) were significantly higher than those in group CM-H ( P<0.05). In the 4-PBA intervention experiment, compared with group 0 mmol/L, the expressions of GRP78, IRE-1, ATF-6, PERK and CHOP were significantly lower in group 1, 10 and 20 mmol/L ( P<0.05). Moreover, compared with control group [(31.23±1.98) ng/L], the expression of IL-1β in THP-1 cells were significantly lower in group 10 mmol/L [(21.20±0.37) ng/L] and group 20 mmol/L [(23.85±1.80) ng/L] ( P<0.05) with ERS inhibited. Conclusions:PDLSC from inflammatory environment could promote IL-1β secretion of macrophages through upregulating macrophages ERS.
5.Research progress on the methods of observation and analysis of dental bonding interfaces
MA Chaoqun ; LIU Meng ; QIU Jun ; LIAO Zixuan ; ZHOU Wei ; CHEN Jihua
Journal of Prevention and Treatment for Stomatological Diseases 2021;29(5):356-360
Dental bonding technology and materials have been used widely in dentistry because of their excellent properties. The development of novel bonding technology and materials is constantly being performed to improve the effect of dental bonding restorations. Observation and analysis of the dental bonding interface is one of the most important methods for laboratory evaluation of bonding efficiency. This paper aims to review the methods of observation and analysis of dental bonding interfaces to provide a reference for the selection of evaluation methods in dental bonding research. The features of 6 methods, including scanning electron microscopy (SEM), transmission electron microscopy (TEM), confocal laser scanning microscopy (CLSM), Raman spectroscopy (RS), optical coherence tomography (OCT) and atomic force microscopy (AFM), were described and summarized. Among these methods, SEM and TEM are used most often in the analysis of fine structures; CLSM and OCT are used for the acquisition of characteristic image signals, such as microleakage and exogenous and endogenous fluorescence; and RS and AFM can test chemical composition and mechanical properties.