Zebrafish as a Model to Unveil the Pro-Osteogenic Effects of Boron-Vitamin D3 Synergism

Abstract

The micronutrient boron (B) plays a key role during the ossification process as suggested by various in vitro and in vivo studies. To deepen our understanding of the molecular mechanism involved in the osteogenicity of B and its possible interaction with vitamin D3 (VD), wild-type AB zebrafish (Danio rerio) were used for morphometric analysis and transcriptomic analysis in addition to taking advantage of the availability of specific zebrafish osteoblast reporter lines. First, osteoactive concentrations of B, VD, and their combinations were established by morphometric analysis of the opercular bone in alizarin red-stained zebrafish larvae exposed to two selected concentrations of B (10 and 100 ng/ml), one concentration of VD (10 pg/ml), and their respective combinations. Bone formation, as measured by opercular bone growth, was significantly increased in the two combination treatments than VD alone. Subsequently, a transcriptomic approach was adopted to unveil the molecular key regulators involved in the synergy. Clustering of differentially expressed genes revealed enrichment toward bone and skeletal functions in the groups co-treated with B and VD. Downstream analysis confirmed mitogen-activated protein kinase as the most regulated pathway by the synergy groups in addition to transforming growth factor-β signaling, focal adhesion, and calcium signaling. The best-performing synergistic treatment, B at 10 ng/ml and VD at 10 pg/ml, was applied to two zebrafish transgenic lines, Tg(sp7:mCherry) and Tg(bglap:EGFP), at multiple time points to further explore the results of the transcriptomic analysis. The synergistic treatment with B and VD induced enrichment of intermediate (sp7+) osteoblast at 6 and 9 days post fertilization (dpf) and of mature (bglap+) osteoblasts at 15 dpf. The results obtained validate the role of B in VD-dependent control over bone mineralization and can help to widen the spectrum of therapeutic approaches to alleviate pathological conditions caused by VD deficiency by using low concentrations of B as a nutritional additive.

First In Vivo Insights on the Effects of Tempol-Methoxycinnamate, a New UV Filter, as Alternative to Octyl Methoxycinnamate, on Zebrafish Early Development

“…In zebrafish, the appearance of the cartilaginous structure can be easily detected 3 or 4 days post-fertilization, and the results obtained herein with the Alcian blue–Alizarin red double staining allowed us to hypothesize that OMC and TMC, similar to other chemical compounds, including metallic elements, pesticides, and drugs [ 30 ], interact with bone metabolism and seem to accelerate bone development, suggesting a possible interaction with the endocrine system. Nevertheless, the acceleration in bone formation has been observed not only in the case of xenobiotic exposure but also in the case of probiotic addiction in the rearing medium [ 31 , 32 , 33 ], suggesting that the presence of the cinnamate moiety in both molecules can boost mineralization.…”

Modulation of miR-146b Expression during Aging and the Impact of Physical Activity on Its Expression and Chondrogenic Progenitors

“…Studies on fin development and regeneration in Danio rerio (zebrafish) have shown similarities to bone and cartilage differentiation observed in humans [32]. While mice and rats are commonly used experimental models to study bone alterations or repair, zebrafish has also emerged as a valuable model for studying skeletal alterations and pathophysiology [29,[33][34][35][36][37].…”

A realistic mixture of ubiquitous persistent organic pollutants affects bone and cartilage development in zebrafish by interaction with nuclear receptor signaling

“…This species has been used to model diseases, genetic conditions, effects of pollutants, and many more across different disciplines. Furthermore, it is a promising model to test environmental chemicals and craniofacial skeletal development [33][34][35].…”