Simple application of adipose-derived stem cell-derived extracellular vesicles coating enhances cytocompatibility and osteoinductivity of titanium implant

Surface modification using bioactive molecules is frequently performed to improve the biological properties of medical metal biomaterial titanium (Ti) implants. Developmental evidence suggests that mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) served as potent bioactive component. As a subset of MSC-EV, adipose-derived stem cell-derived extracellular vesicles (ADSC-EVs) could be obtained from abundant adipose tissue. Meanwhile, it possesses multiple regenerative properties and might be used to endow biological activities to medical Ti implant. Here, we present a simple ADSC-EV coating strategy based on physisorption of fibronectin. This ADSC-EV functionalized Ti implants (EV-Ti) revealed enhanced osteoblast compatibility and osteoinductive activity. Cell spreading area of EV-Ti group was 1.62- and 1.48-fold larger than that of Ti group after 6 and 12 h of cell seeding, respectively. Moreover, EV-Ti promoted alkaline phosphatase, collagen 1 and osteocalcin gene expression in osteoblast by 1.51-, 1.68- and 1.82-fold compared with pristine Ti, respectively. Thus, the MSC-EVs modification method reported here provide a clinically translatable strategy to promote the bioactivity of Ti implants.

OSTEOCALCIN GENE POLYMORPHISM IN INDONESIAN MEN WITH PERIODONTITIS

Objective: Through this work, we aimed to clarify the association between the severity of periodontitis and osteocalcin (OC) gene C298T polymorphismin Indonesian male subjects.Methods: DNA was extracted from blood serum samples of 100 consenting Indonesian men whose periodontitis was classified as mild, moderate,or severe. Polymerase chain reaction and restriction fragment length polymorphism techniques were applied to evaluate the status of OC (C298T)polymorphism using HindIII restriction enzyme and electrophoresis in agarose gel to separate the indicated fragments.Results: Although genotype distribution of the OC C298T polymorphism showed a trend for more frequent occurrence of genotype hh (and allele h)with increasing severity of periodontitis, this trend was not statistically significant in the tested sample population, in whom the HH genotypeappeared to be relatively rare.Conclusion: The results showed no significant association between the severity of periodontitis and OC C298T polymorphism in Indonesian malesubjects.

Down Regulation of Osteocalcin Gene in Chickens Treated with Cadmium

Background: Cadmium is one of the heavy metals with harmful effects on different body organs and systems. The aim of this study was to investigate the harmful effects of cadmium, as a heavy metal, on the histological structure of bone and the expression of osteocalcin gene. Methods: Forty chickens were obtained, anesthetized and their femurs were surgically removed. The real time polymerase chain reaction (PCR) was used to study the osteocalcin gene expression. Results: The osteocalcin gene expression rate were: 1.000± 0.1; 0.86± 0.01; 0.63± 0.09, and 0.41± 0.06 in the controls, experiment I, experiment II and experiment III groups, respectively (P < 0.05). Also, the nuclear pyknosis in osteocytes and decreased bone formation were observed in the histology slides of the chicken bones. Conclusions: We conclude that cadmium adversely affected the chicken bones as evident by the decreased osteocalcin gene expression and the adverse effects on the bone histology. We recommend that plans be developed to prevent the outbreak of cadmium and other heavy metals in animal and human environment.

Effects of Electrostatic Field on Osteoblast Cells for Bone Regeneration Applications

Many external stimulations have been shown to promote bone regeneration. The effects of an alternating current (AC) electrostatic field, one of external stimulations, generated from a device with high voltage and low current output on human osteoblastic cell line have been investigated in this study. We investigated how human osteoblasts responded to an AC electrostatic field, and the output parameters were set as 1 kV and 160 μA. Our results showed that, under such condition, the AC electrostatic field had a downregulation effect on the production ability of alkaline phosphatase and type 1 collagen expression. However, the expression of osteocalcin gene was elevated on the end of EFID treatment suggesting that AC electrostatic field might be a potential stimulation for accelerating the differentiation of osteoblastic cells.