The effect of sericin application over hydroxyapatite surface on osteoblast cells proliferation

Background:: Icariin (ICA), one of the main effective components isolated from the traditional Chinese herb Epimedium brevicornu Maxim., has been reported to possess extensive pharmacological actions, including enhanced sexual function, immune regulation, anti-inflammation, and antiosteoporosis. Methods:: Our study was designed to investigate the effect of ICA on cell proliferation and differentiation and the molecular mechanism of OPG/RANKL mediated by the Estrogen Receptor (ER) in hFOB1.19 human osteoblast cells. Results:: The experimental results show that ICA can stimulate cell proliferation and increase the activity of Alkaline Phosphatase (ALP), Osteocalcin (BGP) and I Collagen (Col I) and a number of calcified nodules. Furthermore, the mRNA and protein expression of OPG and RANKL and the OPG/ RANKL mRNA and protein expression ratios were upregulated by ICA. The above-mentioned results indicated that the optimal concentration of ICA for stimulating osteogenesis was 50ng/mL. Subsequent mechanistic studies comparing 50ng/mL ICA with an estrogen receptor antagonist demonstrated that the effect of the upregulated expression is connected with the estrogen receptor. In conclusion, ICA can regulate bone formation by promoting cell proliferation and differentiation and upregulating the OPG/RANKL expression ratio by the ER in hFOB1.19 human osteoblast cells.

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AT1 and AT2 Receptor Knockout Changed Osteonectin and Bone Density in Mice in Periodontal Inflammation Experimental Model

International Journal of Molecular Sciences ◽

10.3390/ijms22105217 ◽

2021 ◽

Vol 22 (10) ◽

pp. 5217

Author(s):

Maria Laura de Souza Lima ◽

Caroline Addison Carvalho Xavier de Medeiros ◽

Gerlane Coelho Bernardo Guerra ◽

Robson Santos ◽

Michael Bader ◽

...

Keyword(s):

Bone Density ◽

Bone Loss ◽

Experimental Model ◽

At2 Receptor ◽

Micro Ct ◽

Rt Pcr ◽

Osteoblast Cells ◽

Periodontal Inflammation ◽

Bone Trabeculae

Background: The aim of this study was to evaluate the role of AT1 and AT2 receptors in a periodontal inflammation experimental model. Methods: Periodontal inflammation was induced by LPS/Porphyromonas gingivalis. Maxillae, femur, and vertebra were scanned using Micro-CT. Maxillae were analyzed histopathologically, immunohistochemically, and by RT-PCR. Results: The vertebra showed decreased BMD in AT1 H compared with WT H (p < 0.05). The femur showed increased Tb.Sp for AT1 H and AT2 H, p < 0.01 and p < 0.05, respectively. The Tb.N was decreased in the vertebra (WT H-AT1 H: p < 0.05; WT H-AT2 H: p < 0.05) and in the femur (WT H-AT1 H: p < 0.01; WT H-AT2 H: p < 0.05). AT1 PD increased linear bone loss (p < 0.05) and decreased osteoblast cells (p < 0.05). RANKL immunostaining was intense for AT1 PD and WT PD (p < 0.001). OPG was intense in the WT H, WT PD, and AT2 PD when compared to AT1 PD (p < 0.001). AT1 PD showed weak immunostaining for osteocalcin compared with WT H, WT PD, and AT2 PD (p < 0.001). AT1 H showed significantly stronger immunostaining for osteonectin in fibroblasts compared to AT2 H (p < 0.01). Conclusion: AT1 receptor knockout changed bone density, the quality and number of bone trabeculae, decreased the number of osteoblast cells, and increased osteonectin in fibroblasts.

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Overexpression of CRABP2 inhibits dexamethasone-induced apoptosis in human osteoblast cells

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-021-02386-6 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Haiping Zhang ◽

Ziliang Yu ◽

Farui Sun ◽

Jin Jin

Keyword(s):

Protein Expression ◽

Underlying Mechanism ◽

R Package ◽

Treated Group ◽

Gene Expression Omnibus ◽

Human Osteoblast ◽

Osteoblast Cells ◽

Gene And Protein Expression ◽

Osteoblast Apoptosis ◽

Induced Apoptosis

Abstract Background The purpose of the current study was to explore the role and underlying mechanism of cellular retinoic acid binding protein 2 (CRABP2) in dexamethasone (DEX)-induced apoptosis in human osteoblast cells. Methods GSE10311 was downloaded from the Gene Expression Omnibus (GEO) database to identify the differentially expressed genes (DEGs) by the limma/R package. Primary human osteoblast was isolated and treated with different concentration of DEX (0, 10-8, 10-7, 10-6, 10-5, and 10-4 mol/L), and cell viability and flow cytometry were used to detect cell proliferation and apoptosis. A CRABP2 overexpression plasmid (oe-CRABP2) was used to overexpress CRABP2, and western blotting was conducted to detect protein expression. Results We found that CRABP2 was downregulated in the DEX-treated group. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses indicated that DEGs were associated with PI3K/Akt signaling pathway. DEX downregulated CRABP2 gene and protein expression, inhibited viability, and induced human osteoblast apoptosis. Overexpression of CRABP2 reversed DEX-induced apoptosis in human osteoblast. Moreover, overexpression of CRABP2 delayed the progression of DEX-induced osteonecrosis of the femoral head (ONFH) animal model. Conclusion In conclusion, CRABP2 is effective at inhibiting DEX-induced human osteoblast apoptosis and delayed ONFH progression.

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Surface Properties and Biocompatibility of Anodized Titanium with a Potential Pretreatment for Biomedical Applications

Metals ◽

10.3390/met11071090 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1090

Author(s):

Bai-Hung Huang ◽

Yi-Jung Lu ◽

Wen-Chien Lan ◽

Muhammad Ruslin ◽

Hung-Yang Lin ◽

...

Keyword(s):

Porous Structure ◽

Biomedical Applications ◽

Grazing Incidence ◽

Acid Pretreatment ◽

Osteoblast Cells ◽

In Vitro Biocompatibility ◽

Porous Ti ◽

Diphenyltetrazolium Bromide ◽

Anodized Titanium

The effects of anodized titanium (Ti) with a potential hydrogen fluoride (HF) acid pretreatment through cathodization on the formation of nano-porous Ti dioxide (TiO2) layer were characterized using field-emission scanning electron microscopy, grazing incidence X-ray diffractometer, and contact angle goniometer. The biocompatibility was determined by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) test. Analytical results found that a well-aligned nano-porous structure was formed on the anodized Ti surface with HF pretreatment concentration above 0.5%. Microstructure of the nano-porous Ti dioxide surface generated by anodization with HF pretreatment was composed of anatase and rutile phases, while the anodized Ti sample with HF pretreatment concentration of 0.5% presented excellent hydrophilicity surface. An in-vitro biocompatibility also indicated that osteoblast cells grown on the surface of the anodized Ti sample with HF pretreatment increased with the increase of culture time. The filopodia of osteoblast cells not only adhered flat, but also tightly grabbed the nano-porous structure for promoting cell adhesion and proliferation. Therefore, the anodized Ti with HF pretreatment can form a functionalized surface with great biocompatibility for biomedical applications, particularly for dental implants.

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