ABSTRACT
Purpose@#Although activating thermogenic adipocytes is a promising strategy to reduce the risk of obesity and related metabolic disorders, emerging evidence suggests that it is difficult to induce adipocyte thermogenesis in obesity. Therefore, this study aimed to investigate the regulation of adipocyte thermogenesis in diet-induced obesity. @*Methods@#Adipose progenitor cells were isolated from the white and brown adipose tissues of control diet (CD) or high-fat diet (HFD) fed mice, and fully differentiated white and brown adipocytes were treated with β-agonists or 18-carbon fatty acids for β-adrenergic activation or peroxisome proliferator-activated receptor (PPAR) activation. @*Results@#Compared to the CD-fed mice, the expression of uncoupling protein 1 (Ucp1) was lower in the white adipose tissue of the HFD-fed mice; however, this was not observed in the brown adipose tissue. The expression of peroxisome proliferator-activated receptor gamma (Pparg) was lower in the brown adipose progenitor cells isolated from HFD-fed mice than in those isolated from the CD-fed mice. Norepinephrine (NE) treatment exerted lesser effect on peroxisome proliferator-activated receptor-γ coactivator (Pgc1a) upregulation in white adipocytes derived from HFD-fed mice than those derived from CD-fed mice. Regardless which 18-carbon fatty acids were treated, the expression levels of thermogenic genes including Ucp1, Pgc1a, and positive regulatory domain zinc finger region protein 16 (Prdm16) were higher in the white adipocytes derived from HFD-fed mice. Oleic acid (OLA) and γ-linolenic acid (GLA) upregulated Pgc1a expression in white adipocytes derived from HFDfed mice. Brown adipocytes derived from HFD-fed mice had higher expression levels of Pgc1a and Prdm16 compared to their counterparts. @*Conclusion@#These results indicate that diet-induced obesity may downregulate brown adipogenesis and NE-induced thermogenesis in white adipocytes. Also, HFD feeding may induce thermogenic gene expression in white and brown primary adipocytes, and OLA and GLA could augment the expression levels.
ABSTRACT
The long setting time of dental MTA (Mineral Trioxide Aggregate) cement is a major disadvantage in clinical use. In this study, the setting time (ST) of nine commercial MTA cements was tested according to the ISO 6876:2012 standard (n = 5).Materials evaluated were ProRoot MTA (PR), Ortho MTA (Ortho), Retro MTA (Retro), Endocem MTA (Endocem), Endoseal MTA (Endoseal), One-Fil (OF), MTA Cem (MC), EZ-Seal (EZ), and Biodentine (BD). XRD and XRF analysis were performed to evaluate the effect of composition on ST. Kruskal-Wallis test as a non-parametric ANOVA followed by Duncan’s post hoc test was used for statistical analysis. The ST was PR > EZ > OF > Ortho > Retro > MC > Endoseal > BD > Endocem in decreasing order (p < 0.001). PR showed the longest (369.4 min) and Endocem showed the shortest (2.4 min) ST. Endocem (2.4 min), BD (16.0 min) and Endoseal (47.0 min) contained calcium carbonate. MC (48.8 min), Retro (43.6 min), Ortho (65.0), and OF (165.4 min), which had the next short setting time, contained dicalcium aluminate. In EZ (182.4 min), dicalcium silicate was the main crystalline phase rather than tricalcium silicate, which contributes to the early strength, and it contained calcium sulfate. Endocem, which showed the shortest setting time, showed the smallest d90 particle size of 6.12 µm. The information obtained from this study would be helpful in developing a composition for controlling the setting time of MTA cement and selecting a product with a setting time suitable for each clinical case.
ABSTRACT
The long setting time of dental MTA (Mineral Trioxide Aggregate) cement is a major disadvantage in clinical use. In this study, the setting time (ST) of nine commercial MTA cements was tested according to the ISO 6876:2012 standard (n = 5).Materials evaluated were ProRoot MTA (PR), Ortho MTA (Ortho), Retro MTA (Retro), Endocem MTA (Endocem), Endoseal MTA (Endoseal), One-Fil (OF), MTA Cem (MC), EZ-Seal (EZ), and Biodentine (BD). XRD and XRF analysis were performed to evaluate the effect of composition on ST. Kruskal-Wallis test as a non-parametric ANOVA followed by Duncan’s post hoc test was used for statistical analysis. The ST was PR > EZ > OF > Ortho > Retro > MC > Endoseal > BD > Endocem in decreasing order (p < 0.001). PR showed the longest (369.4 min) and Endocem showed the shortest (2.4 min) ST. Endocem (2.4 min), BD (16.0 min) and Endoseal (47.0 min) contained calcium carbonate. MC (48.8 min), Retro (43.6 min), Ortho (65.0), and OF (165.4 min), which had the next short setting time, contained dicalcium aluminate. In EZ (182.4 min), dicalcium silicate was the main crystalline phase rather than tricalcium silicate, which contributes to the early strength, and it contained calcium sulfate. Endocem, which showed the shortest setting time, showed the smallest d90 particle size of 6.12 µm. The information obtained from this study would be helpful in developing a composition for controlling the setting time of MTA cement and selecting a product with a setting time suitable for each clinical case.