All‐trans retinoic acid and human salivary histatin‐1 promote the spreading and osteogenic activities of pre‐osteoblasts in vitro

Abstract

Cell‐based bone tissue engineering techniques utilize both osteogenic cells and biomedical materials, and have emerged as a promising approach for large‐volume bone repair. The success of such techniques is highly dependent on cell adhesion, spreading, and osteogenic activities. In this study, we investigated the effect of co‐administration of all‐trans retinoic acid (ATRA) and human salivary peptide histatin‐1 (Hst1) on the spreading and osteogenic activities of pre‐osteoblasts on bio‐inert glass surfaces. Pre‐osteoblasts (MC3T3‐E1 cell line) were seeded onto bio‐inert glass slides in the presence and absence of ATRA and Hst1. Cell spreading was scored by measuring surface areas of cellular filopodia and lamellipodia using a point‐counting method. The distribution of fluorogenic Hst1 within osteogenic cells was also analyzed. Furthermore, specific inhibitors of retinoic acid receptors α, β, and γ, such as ER‐50891, LE‐135, and MM‐11253, were added to identify the involvement of these receptors. Cell metabolic activity, DNA content, and alkaline phosphatase (ALP) activity were assessed to monitor their effects on osteogenic activities. Short‐term (2 h) co‐administration of 10 μm ATRA and Hst1 to pre‐osteoblasts resulted in significantly higher spreading of pre‐osteoblasts compared to ATRA or Hst1 alone. ER‐50891 and LE‐135 both nullified these effects of ATRA. Co‐administration of ATRA and Hst1 was associated with significantly higher metabolic activity, DNA content, and ALP activity than either ATRA or Hst1 alone. In conclusion, co‐administration of Hst1 with ATRA additively stimulated the spreading and osteogenicity of pre‐osteoblasts on bio‐inert glass surfaces in vitro.

Human Salivary Histatin-1 Is More Efficacious in Promoting Acute Skin Wound Healing Than Acellular Dermal Matrix Paste

“…Such a rapid effect of Hst1 may be probably explained by the findings that Hst1 was quickly taken up by cells ( Ma et al, 2020 ) and exert promoting effects on cell spreading and migration within several hours ( van Dijk et al, 2017 ; Ma et al, 2020 ). Our results also showed that the most effective concentration of Hst1 in this in vivo acute wound model was 10 μM, which was consistent with the in vitro findings ( Shah et al, 2017 ; van Dijk et al, 2017 ; Sun et al, 2020 ). Hst1 promotes wound healing possibly through it potent capacity of enhancing the migration of epithelial cells ( Oudhoff et al, 2009a ; Oudhoff et al, 2009b ; Shah et al, 2017 ; van Dijk et al, 2017 ) and fibroblasts ( van Dijk et al, 2015 ), which is mediated by the C-terminal amino acid sequence of Hst1 ( Sun et al, 2009 ) and G-protein coupled receptors ( Oudhoff et al, 2009a ) and ERK1/2 signaling pathway ( Oudhoff et al, 2008 ).…”

Human Salivary Histatin-1 Promotes Osteogenic Cell Spreading on Both Bio-Inert Substrates and Titanium SLA Surfaces

“…Hitherto, this issue is rarely reported. In our recent study, we show that Hst1 alone does not promote ALP activity (Sun W. et al, 2020).…”

“…Our previous studies suggest that the promoting effect of Hst1 on the migration of epithelial cells is mediated by the GPCRs-ERK1/2 pathway, but not by the p38 pathway (Oudhoff et al, 2009a). Our recent study shows that co-administration of Hst1 with all-trans retinoic acid additively stimulates the spreading and osteogenicity of preosteoblasts on bio-inert glass surfaces in vitro, which can be abolished by specific inhibitors of retinoic acid receptors α (but not β or γ) (Sun W. et al, 2020). However, the signaling pathways accounting for the Hst1's effect on the pre-osteoblasts' adhesion remains to be clarified.…”

Histatin‐1 is a novel osteogenic factor that promotes bone cell adhesion, migration, and differentiation

“…Specifically, a recent study from our group showed that Histatin‐1 decreases cytotoxicity of zoledronic acid, an antiresorptive drug, in MC3T3‐E1 preosteoblasts and SAOS‐2 osteosarcoma cells (Castro et al., 2019). The remaining two studies evaluated the effects of Histatin‐1 on MC3T3‐E1 cells (Sun, Shi, Ma et al., 2020; Van Dijk, Beker et al., 2017). Specifically, in one study, Histatin‐1 was shown to increase cell adhesion to titanium surfaces (Van Dijk Beker et al., 2017), whereas the other study showed that Histatin‐1 increases the effects of all‐ trans retinoic acid on the activity of ALP, which is an enzyme associated with matrix mineralization (Sun, Shi, Ma et al., 2020).…”

“…The latter is intriguing, because it extends the spectrum of cells that are sensitive to Histatin‐1, raising the possibility that Histatin‐1 impinges on aspects of bone cell biology. Another recent study explored a possible relationship between Histatin‐1 and the osteogenic differentiation agent all trans retinoic acid in MC3T3‐E1 preosteoblasts, showing that both molecules promote cell spreading and the activity of alkaline phosphatase (ALP), which is involved in bone mineralization (Sun, Shi, Ma et al., 2020). However, that study showed no alterations in ALP activity upon treatment with Histatin‐1 alone, which might be due to the result of brief exposure times or usage of a single cell line.…”