Bisphosphonates Reduce Smoking-Induced Osteoporotic-Like Alterations by Regulating RANKL/OPG in an Osteoblast and Osteoclast Co-Culture Model

Abstract

Co-culture models have become mandatory for obtaining better insights into bone homeostasis, which relies on the balance between osteoblasts and osteoclasts. Cigarette smoking (CS) has been proven to increase the risk of osteoporosis; however, there is currently no proven treatment for osteoporosis in smokers excluding cessation. Bisphosphonates (BPs) are classical anti-osteoclastic drugs that are commonly used in examining the suitability of bone co-culture systems in vitro as well as to verify the response to osteoporotic stimuli. In the present study, we tested the effects of BPs on cigarette smoke extract (CSE)-affected cells in the co-culture of osteoblasts and osteoclasts. Our results showed that BPs were able to reduce CSE-induced osteoporotic alterations in the co-culture of osteoblasts and osteoclasts such as decreased matrix remodeling, enhanced osteoclast activation, and an up-regulated receptor activator of nuclear factor (NF)-kB-ligand (RANKL)/osteoprotegerin (OPG) ratio. In summary, BPs may be an effective alternative therapy for reversing osteoporotic alterations in smokers, and the potential mechanism is through modulation of the RANKL/OPG ratio.

A simple method for decellularizing a cell-derived matrix for bone cell cultivation and differentiation

“…TRAP 5b activity as a marker of osteoclast activity was measured in culture supernatants as previously described [30,31]. Culture supernatant (30 µL) was transferred to a new cell culture plate with 90 μL of TRAP 5b activity assay solution (0.2% w/v 4-nitrophenyl phosphate, 100 mM sodium…”

“…Bright-field images of the stained cells were captured by microscopy (EVOS FL, Thermo Fisher Scientific). For quantitative measurement, the bound Alizarin Red was dissolved with 10% w/v cetylpyridinium chloride solution and quantified photometrically (λ = 562 nm; Omega plate reader) as described previously [31].…”

“…6e). Matrix mineralization, a marker of functionality and differentiation in osteoblasts [31], was assessed by Alizarin Red staining after 14 days of culture (Fig. 6f).…”

Impact of Cigarette Smoking on the Risk of Osteoporosis in Inflammatory Bowel Diseases

“…Additionally, nutritional support, especially an adequate intake of vitamin D and calcium, constitutes an essential element of the therapy [20]. In turn, bisphosphonates are common anti-osteoclastic drugs, but they also reduce cigarette smoking-induced osteoporotic alterations of osteoblasts and osteoclasts [21].…”

“…According to Zhu et al, bisphosphonates may be drugs for osteoporotic patients, especially smokers [21]. Many studies showed that bisphosphonates increase OPG expression and inhibit the expression of RANKL, which is opposed to the impact of nicotine on OPG/RANKL/RANK pathway [31,32].…”