Expression of Glucagon-Like Peptide 1 Receptor during Osteogenic Differentiation of Adipose-Derived Stem Cells

BACKGROUND: Glucagon-like peptide 1 (GLP-1), an incretin hormone well known for its glucose-lowering effect, was recently reported to exert an anabolic effect on bone. Although the exact mechanism is not known, it likely involves the GLP-1 receptor (GLP-1R), which is expressed in some osteoblastic cell lines. Adipose-derived stem cells (ADSCs) have mesenchymal stem cell-specific characteristics, including osteoblastic differentiation potential. We evaluated the expression of GLP-1R during osteogenic differentiation of ADSCs. METHODS: ADSCs were isolated from subcutaneous adipose tissue obtained from three male donors during plastic surgery and were subjected to osteogenic induction. Mineralization was assessed by Alizarin Red staining on day 21. Expression of alkaline phosphatase (ALP), osteocalcin (OC), and GLP-1R was measured by real-time polymerase chain reaction in triplicate for each patient on days 0, 7, 14, and 21. Target mRNA expression levels were normalized to that of beta-actin. RESULTS: ADSCs were fibroblast-like in morphology, adhered to plastic, and had multipotent differentiation potential, as assessed using specific antigen markers. The osteogenic markers ALP and OC were notably upregulated at 21 days. Osteogenic differentiation resulted in a time-dependent increase in the expression of GLP-1R (P=0.013). CONCLUSION: We demonstrated upregulation of GLP-1R gene expression during osteogenic differentiation of ADSCs. This finding suggests that GLP-1 may induce osteogenic differentiation in bone tissue.

The effects of bisphosphonates on differentiation of human amniotic fluid-derived mesenchymal stem cells into osteoblast / 대한산부인과학회지

OBJECTIVE: It has been known that amniotic fluid (AF) is rich source of mesenchymal stem cells (MSCs). Bisphosphonates are widely used in clinical treatment of various metabolic bone diseases and their primary action is the inhibition of osteoclastic bone resorption. However, litter is known about whether bisphosphonates affect the differentiation into osteoblast, especially from AF-derived MSCs (AFMSCs). Therefore, the purpose of this study is to investigate whether these bisphosphonates influence in the process of AFMSCs differentiation into osteoblast. METHODS: AF samples were obtained by second trimester amniocentesis for fetal karyotyping from 6 pregnant women. Cells were treated with various concentration (0, 10(-10), 10(-8), 10(-6) M) of zoledronate and alendronate and analyzed over 21 days of culture. Differentiation into osteoblast was determined by cell staining and RT-PCR for alkaline phosphatase (ALP). RESULTS: It was observed that AFMSCs could differentiate into osteoblast. Alendronate had more potent effect than zoledronate in osteoblastic differentiation. ALP expression was increased with increasing concentration of zoledronate and it was highest in 10(-8) M alendronate. However, no effect of bisphosphonates was found in 14 days of culture. CONCLUSION: This study shows that AFMSCs can be differentiated into osteoblast. The induction of these differentiation following bisphosphonate treatment was appear to be drug type-, dose-, and culture time-dependent. However, further studies are needed to conclude a consistent outcome for the effects of bisphosphonate on differentiation potential of AFMSCs.

The Effect of Zoledronate on the Differentiation of Human Amniotic Fluid-Derived Mesencymal Stem Cells into Adipocytes / 대한수혈학회지

BACKGROUND: Amniotic fluid is a rich source of fetal mesenchymal stem cells (MSCs). However, little is known about whether bisphosphonates affect the differentiation into adipocytes. Therefore, this study was aimed to investigate whether zoledronate influences the differentiation of AFMSCs into adipocytes. METHODS: Amniotic fluid cells samples were obtained from 6 pregnant women by second trimester amniocentesis for performing fetal karyotyping. The cells were treated with various concentration (10(-10), 10(-8), 10(-6) M) of zoledronate and the cells were analyzed over 21 days of culture. Differentiation into adipocytes was determined by oil-red O staining and for fatty acid synthase (FAS), acetyl CoA carboxylase 1 (ACC1) and sterol regulatory elementary binding protein-1 (SREBP-1). RESULTS: Differentiation of AFMSCs into adipocytes was found by oil-red O staining. Zoledronate influenced the differentiation of AFMSCs into adipocytes in a dose- and time-dependent manner. At 7 days of culture, the expressions of FAS and SREBP-1 showed no significant differences compared to that of the control regardless of the dose of zoledronate. Very little ACC1 expression was found. However, the expressions of these three markers were remarkably increased at 14 days of culture. Of them, the ACC1 expression was significantly increased by 10(-8) M and 10(-6) M of zoledronate. At 21 days of culture, there were no effects of zoledronate on the expressions of FAS and SREBP-1. However, the ACC1 expression was decreased with an increasing dose of zoledronate (P<.05). CONCLUSION: This study shows that AFMSCs can be differentiated into adipocytes. The induction of this differentiation following zoledronate treatment appears to be dose dependent and time-of-culture dependent.

Relationship between The Expressions of Sodium/Iodide Symporter and The Findings of Thallium-201 Scan in Thyroid Nodules / 대한내분비학회지

BACKGROUND: The sodium/iodide symporter (NIS) has an important role in the diagnosis and treatment of well differentiated thyroid carcinoma. The relationship between the uptake of thallium- 201 scan (201Tl scan) and the expression of sodium/iodide symporter (hNIS) was studied in thyroid nodules. METHODS: Patients that had undergone operations for thyroid nodules, and who received a 201Tl scan before their operations, were investigated. Anti-NIS antibodies were used to analyze the presence and distribution of the hNIS protein by immunohistochemical staining of their thyroid tissues. RESULTS: Forty-four patients (papillary carcinoma; 18, follicular adenoma; 11, adenomatous goiter; 14, nonspecific thyroiditis; 1) 30 with no immunoreactivity and 14 with a positive reaction to the anti-NIS antibody, were included. The NIS negative patients (12/30) had no 201Tl uptake, but all others were positive on 201Tl scan, and the NIS-positive patients (13/14) had positive 201Tl uptake, with 1 negative on 201Tl scan, with significant difference (p=0.035). Of the 18 patients with a papillary thyroid carcinoma, the NIS negative patients (2/10) had no 201Tl uptake and the others were positive on 201Tl scan, but without significant difference. NIS positive patients (1/8) with a papillary thyroid carcinoma had no 201Tl uptake, and the others were positive on 201Tl scan, but without significant difference. Whether the results of NIS staining and 201Tl scan were positive or not did not affect the responses of radioactive iodine therapy in our study. CONCLUSION: These results suggest that thallium-201 uptake may be correlated with hNIS expression in thyroid nodules