DMSO regulates osteoclast development in vitro

Abstract

Dimethyl sulfoxide (DMSO) is routinely used in the laboratory as a solvent and vehicle for organic molecules. Although it has been used in previous studies involving myeloid cells and macrophages, we are unaware of data demonstrating the effects of DMSO alone on osteoclast development. Recently, we were using DMSO as a vehicle and included a non-vehicle control. Surprisingly, we observed a marked change in osteoclast development, and therefore designed this study to examine the effects of DMSO on osteoclast development. Osteoclasts were generated from two sources: bone marrow macrophages and an osteoclast progenitor cell line. Cells were cultured with DMSO for various durations and at differing concentrations and mature, multinucleated (>3 nuclei) TRAP+ cells were assessed in terms of cell number, cell surface area, and number of nuclei/cell. Osteoclast surface area increased in 5 μM DMSO to a mean of 156,422 pixels from a mean of 38,510 pixels in control culture, and subsequently decreased in 10 μM DMSO to a mean of 18,994 pixels. With serial addition of DMSO over 5 d, a significant increase in mean surface area, and number of nuclei/cell was also observed, while the opposite was true when DMSO was serially removed from culture. These findings show that DMSO exerts a marked effect on osteoclast differentiation. Since many investigators use DMSO to solubilize compounds for treatment of osteoclasts, caution is warranted as altering DMSO concentrations may have a profound effect on the final data, especially if osteoclast differentiation is being assessed.

Inhibition of differentiation and function of osteoclasts by dimethyl sulfoxide (DMSO)

“…Although Lemieux et al (2011) reported inhibition of formation of osteoclasts by DMSO in vitro for the first time, our study is the first to reveal mechanistic details. In addition to the osteoclastinhibiting property, DMSO (1 % concentration) is also known to enhance osteoblastic differentiation of murine preosteoblastic MC3T3-E1 cells and the mineralization of primary osteoblasts of human origin (0.35-1 % concentration) (Cheung et al 2006;Stephens et al 2011).…”

“…Lemieux et al (2011) reported enhancement of osteoclastogenesis at 5 μM DMSO concentration while reporting inhibition of osteoclastogenesis at concentration of 20 μM. However, these authors used an osteoclast progenitor cell line derived from the spleens of Pax5 -/-mice and primary bone marrow-derived macrophages obtained from B6 mice, while we utilized a conventional murine model system of RAW 264.7 cells as osteoclast precursors.…”

“…This suggests that concentrations derived from our study (1 % DMSO) are easily deliverable for the purposes of the inhibition of osteoclasts. However, considering the fact that DMSO at lower concentrations enhances osteoclast differentiation (Lemieux et al 2011), as well as the expression of integrin αVβ3 that is required for the attachment of osteoclasts to bone (Fig. 5), and that the DMSO effect is cell-type-specific, further studies to determine the optimum DMSO concentration to inhibit osteoclast precursors of human origin are essential.…”

“…The literature search on this aspect revealed to us that DMSO was indeed reported to inhibit the formation of osteoclasts in vitro (Lemieux et al 2011). While this important report shed light on this phenomenon for the first time, it was observation-oriented and the mechanisms involved were not investigated in detail.…”

Luteolin inhibition of V‐ATPase a3–d2 interaction decreases osteoclast resorptive activity

“…Zhang et al [2008a] and Kim et al [2011], specify that DMSO was used as the carrier. It has been demonstrated that osteoclast differentiation is sensitive to low concentrations of DMSO [Lemieux et al, 2011], and it is possible that it might have synergistic effects with bioactive molecules, like luteolin. In the present work we used ≥98% pure luteolin (Sigma catalog no.…”