Diallyl-disulphide is the effective ingredient of garlic oil that protects primary human osteoblasts from damage due to cigarette smoke

Cigarette consumption negatively affects bone-matter and -stability, partially due to increased oxidative stress. Garlic has been shown to have anti-oxidative properties. Therefore, the intention was to investigate whether garlic oil blend (GOB) reduces cellular damage in human osteoblasts exposed to cigarette smoke medium (CSM). Formation of ROS was rapidly induced in osteoblasts exposed to CSM and their viability decreased in a concentration- and time-dependent manner (EC₅₀ ≈ 0.75 OD₃₂₀). Co-, pre- and post-incubation with GOB significantly improved their viability. Testing both major components of GOB, diallyl-sulphide (DAS) and diallyl-disulphide (DADS), showed that DADS is more efficient. DADS markedly induced the expression of the anti-oxidative enzyme haeme-oxygenase (HO)-1. The HO-1 inhibitor zinc-protoporphyrin reduced the protective effect of all three substances. Summarizing, CSM damages osteoblasts by accumulation of ROS. GOB and especially DADS reduce this damage by scavenging the radicals and by up-regulating HO-1. Thus, a garlic rich diet or dietary supplementation with DADS might improve bone-matter, -stability and even fracture healing in smokers.     

Nitric oxide-induced apoptosis in human pancreatic carcinoma cell lines is associated with a G1-arrest and an increase of the cyclin-dependent kinase inhibitor p21WAF1/CIP1

Nitric oxide (NO) is a messenger molecule with various biological activities including DNA damage. In the present study, we examined the influence of endogenously produced NO on human pancreatic cell lines. In response to cytokine stimulation (tumor necrosis factor alpha, IFN-gamma, and interleukin 1beta), human pancreatic carcinoma cell lines expressed the inducible NO synthase that synthesizes NO, detectable as nitrate and nitrite in the culture supernatants. Endogenously produced NO induced apoptosis in all of the tested pancreatic carcinoma cell lines. In cell cycle analysis, endogenous production of NO revealed a G1-arrest in all of the tested cell lines. This G1-arrest was blockable by addition of NG-monomethyl-L-arginine. These data indicate that NO induces a G1-arrest followed by apoptosis in pancreatic carcinoma cell lines.     

Exposure to 16 Hz Pulsed Electromagnetic Fields Protect the Structural Integrity of Primary Cilia and Associated TGF-β Signaling in Osteoprogenitor Cells Harmed by Cigarette Smoke

Cigarette smoking (CS) is one of the main factors related to avoidable diseases and death across the world. Cigarette smoke consists of numerous toxic compounds that contribute to the development of osteoporosis and fracture nonunion. Exposure to pulsed electromagnetic fields (PEMF) was proven to be a safe and effective therapy to support bone fracture healing. The aims of this study were to investigate if extremely low frequency (ELF-) PEMFs may be beneficial to treat CS-related bone disease, and which effect the duration of the exposure has. In this study, immortalized human mesenchymal stem cells (SCP-1 cells) impaired by 5% cigarette smoke extract (CSE) were exposed to ELF-PEMFs (16 Hz) with daily exposure ranging from 7 min to 90 min. Cell viability, adhesion, and spreading were evaluated by Sulforhodamine B, Calcein-AM staining, and Phalloidin-TRITC/Hoechst 33342 staining. A migration assay kit was used to determine cell migration. Changes in TGF-β signaling were evaluated with an adenoviral Smad2/3 reporter assay, RT-PCR, and Western blot. The structure and distribution of primary cilia were analyzed with immunofluorescent staining. Our data indicate that 30 min daily exposure to a specific ELF-PEMF most effectively promoted cell viability, enhanced cell adhesion and spreading, accelerated migration, and protected TGF-β signaling from CSE-induced harm. In summary, the current results provide evidence that ELF-PEMF can be used to support early bone healing in patients who smoke.     

Altered Secretome of Diabetic Monocytes Could Negatively Influence Fracture Healing—An In Vitro Study

Diabetes mellitus is a main risk factor for delayed fracture healing and fracture non-unions. Successful fracture healing requires stimuli from different immune cells, known to be affected in diabetics. Especially, application of mononuclear cells has been proposed to promote wound and fracture healing. Thus, aim was to investigate the effect of pre-/diabetic conditions on mononuclear cell functions essential to promote osteoprogenitor cell function. We here show that pre-/diabetic conditions suppress the expression of chemokines, e.g., CCL2 and CCL8 in osteoprogenitor cells. The associated MCP-1 and MCP-2 were significantly reduced in serum of diabetics. Both MCPs chemoattract mononuclear THP-1 cells. Migration of these cells is suppressed under hyperglycemic conditions, proposing that less mononuclear cells invade the site of fracture in diabetics. Further, we show that the composition of cytokines secreted by mononuclear cells strongly differ between diabetics and controls. Similar is seen in THP-1 cells cultured under hyperinsulinemia or hyperglycemia. The altered secretome reduces the positive effect of the THP-1 cell conditioned medium on migration of osteoprogenitor cells. In summary, our data support that factors secreted by mononuclear cells may support fracture healing by promoting migration of osteoprogenitor cells but suggest that this effect might be reduced in diabetics.     

Design of Rotman lens for beamsteering of 94 GHz antenna array

The design and development of a Rotman lens for operation at 94 GHz which feeds an antenna array for beamsteering applications is presented. The construction is completely realised in waveguide technology. The lens consists of 15 beam ports covering a scan range of /spl plusmn/23.3/spl deg/ in steps of 3.3/spl deg/ and 10 array ports connected via phase compensating transmission lines to a linear antenna array. Experimental results are compared with theoretical calculations.     

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

Journal of Materials Science: Materials in Medicine - Surface modification of superparamagnetic Fe3O4 nanoparticles using polymers (polyaniline/polypyrrole) was done by radio frequency (r.f.)...     

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

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.     

3D Environment Is Required In Vitro to Demonstrate Altered Bone Metabolism Characteristic for Type 2 Diabetics

A large British study, with almost 3000 patients, identified diabetes as main risk factor for delayed and nonunion fracture healing, the treatment of which causes large costs for the health system. In the past years, much progress has been made to treat common complications in diabetics. However, there is still a lack of advanced strategies to treat diabetic bone diseases. To develop such therapeutic strategies, mechanisms leading to massive bone alterations in diabetics have to be well understood. We herein describe an in vitro model displaying bone metabolism frequently observed in diabetics. The model is based on osteoblastic SaOS-2 cells, which in direct coculture, stimulate THP-1 cells to form osteoclasts. While in conventional 2D cocultures formation of mineralized matrix is decreased under pre-/diabetic conditions, formation of mineralized matrix is increased in 3D cocultures. Furthermore, we demonstrate a matrix stability of the 3D carrier that is decreased under pre-/diabetic conditions, resembling the in vivo situation in type 2 diabetics. In summary, our results show that a 3D environment is required in this in vitro model to mimic alterations in bone metabolism characteristic for pre-/diabetes. The ability to measure both osteoblast and osteoclast function, and their effect on mineralization and stability of the 3D carrier offers the possibility to use this model also for other purposes, e.g., drug screenings.