Inhibition of VEGF gene expression in osteoblast cells by different NSAIDs

Highlights

• NSAIDs reduce VEGF gene expression in osteoblasts (HOp and MG-63).

• The reduction of VEGF gene expression was more marked on the HOp line.

• Further research in osteoblast is warranted to fully elucidate these mechanisms.

Abstract

Objective

To determine the effect of different nonsteroidal anti-inflammatory drugs (NSAIDs) on vascular endothelial growth factor (VEGF) gene expression in two osteoblast cell populations.

Design

Osteoblasts obtained by primary culture (HOp) and human osteosarcoma cell line MG63 (MG-63), which were treated with 10 μM doses of acetaminophen, indomethacin, ketoprofen, diclofenac, ibuprofen, ketorolac, naproxen or piroxicam. At 24 h of treatment, their gene expression of VEGF was evaluated by real-time polymerase chain reaction (RT-PCR) and compared with the expression in untreated cells (control group).

Results

The treatment with the different NSAIDs significantly reduced VEGF expression regardless of the cell line and NSAID studied.

Conclusion

The results of this study suggest that these drugs may have undesirable effects on the osteoblast and its bone-forming capacity, given the effect of this growth factor on these cells. Further studies are warranted to determine their repercussions on bone tissue and to elucidate the cell signaling mechanism/s involved.

Introduction

Osteoblast lineage cells, which derive from mesenchymal stem cells, are an important potential target for bone anabolic agents. Osteoblasts synthesize bone matrix for bone formation and play crucial roles in mineral metabolism, hematopoiesis, and bone resorption (Datta, Ng, Walker, Tuck, & Varanasi, 2008). They therefore exert an important function in bone remodeling and regeneration and in all clinical situations requiring new bone tissue formation, including fractures or surgery affecting bone (Berendsen & Olsen, 2015). Nonsteroidal anti-inflammatory drugs (NSAIDs) administration is frequent in these clinical situations due to their analgesic and anti-inflammatory action. However, NSAIDs can have undesirable effects on osteoblasts by altering their physiology (García-Martínez, De Luna-Bertos, Ramos-Torrecillas, Manzano-Moreno, & Ruiz, 2015). Potential effects of NSAIDs on osteoblasts include a reduction in their growth by apoptosis induction or differentiation inhibition (Chang et al., 2009; De Luna-Bertos et al., 2013; De Luna-Bertos, Ramos-Torrecillas, Manzano-Moreno, García-Martínez, & Ruiz, 2015; Díaz-Rodríguez, García-Martínez, Morales et al., 2012; Díaz-Rodríguez, García-Martínez, Arroyo-Morales, Rubio-Ruiz, & Ruiz, 2010; Díaz-Rodríguez, García-Martínez, De Luna-Bertos et al., 2012).

Bone is a highly vascularized tissue, which involves a high degree of communication between blood vessel cells and bone cells in different stages, e.g., bone formation or development, fracture healing, or bone regeneration (Clarkin & Gerstenfeld, 2013). Osteoblasts are the main source of angiogenic factors, such as the vascular endothelial growth factor (VEGF) (Hu & Olsen, 2016), and the blood vessels formed can provide the oxygen, nutrients, minerals, and different factors secreted (even by the osteoblast itself), which are required for bone formation (Kusumbe, Ramasamy, & Adams, 2014). VEGFs also have a key role in bone remodeling by activating the synthesis of receptor activator NK-κB ligand/osteoprotegerin (RANKL/OPG), molecules involved in osteoclast activation (Hu & Olsen, 2016; Huang, Ma, & Kyrkanides, 2016).

The objective of the present study was to analyze the possible effect of different NSAIDs (acetaminophen, indomethacin, ketoprofen, diclofenac, ibuprofen, ketorolac, naproxen, and piroxicam) on VEGF gene expression in two osteoblast cell populations: human osteoblasts obtained by primary culture (HOp) and the MG63 osteoblast line.