Developmental exposure to estrogens has been shown to affect a number of organ systems, including long and short bones. Epigenetic effects of DES exposure have been shown to affect the third generation of progeny. Furthermore, recent studies have shown that environmental exposure to estrogen-like compounds is much higher than originally anticipated. This study aims to discover the effect of in utero exposure to a well-known estrogen agonist, diethylstilbestrol (DES), on lumbar bone, intervertebral disc (IVD), and articular cartilage. Femoral bone was studied to determine the specificity of the effect. C57bl/6n pregnant mice were dosed orally with vehicle (peanut oil) or 0.1, 1.0 and 10 g/kg/day of DES on gestational days 11–14. Male and female pups were allowed to mature without further treatment until 3 months of age, at which point they were divided into swim and sedentary groups. After sacrifice, bone mineral density (BMD), bone mineral content (BMC), bone area (BA), and trabecular bone area (TBA) of the lumbar vertebrae and femur were measured using a PIXImus Bone Densitometer System (GE Medical Systems). Glycosaminoglycan (GAG) content (proteoglycan) was measured by the DMMB assay. Histological analysis of proteoglycan was performed with Safranin O staining. Intervertebral disc height was measured using NDP software (Leeds, UK). Statistical analysis was performed using analysis of variance (ANOVA) followed by Fisher's Protected Least Significant Difference (PLSD). A p-value of < 0.05 was considered statistically significant.Purpose
Method
Metal-on-metal (MoM) articulations in total hip replacement (THR) have become an attractive option for young, active patients. Short-term reports have demonstrated elevated systemic metal ion levels in the blood and urine. Disseminated concentrations of cobalt and chromium have raised concern regarding cellular toxicity, chromosomal damage and adverse local soft tissue reactions. Long-term studies are required to support the increased use of MoM bearings in younger patients given their potential deleterious effects. The purpose of the current study was to report the seven to 13 year clinical, radiographic, and metal ion results in patients following MoM THR. We prospectively followed 165 patients (196 hips) after second-generation MoM THR between July 1997 and November 2003. Functional outcome was measured using the Harris Hip Score (HHS) and the University of California Los Angeles (UCLA) Activity Score. Radiographic analysis was performed using Einzel-Bild-Roentgen-Analyse (EBRA) by two of the authors blinded to the study. Cobalt and chromium metal ions were measured from whole blood and analyzed using inductively coupled plasma-mass spectrometry as previously described.Purpose
Method
A major drawback of current cartilage and intervertebral disc (IVD) tissue engineering is that human mesenchymal stem cells (MSCs) from osteoarthritic (OA) patients express high levels of type X collagen. Type X collagen is a marker of late stage chondrocyte hypertrophy, linked with endochondral ossification, which precedes bone formation. However, it has been shown that a novel plasma-polymer, called nitrogen-rich plasma-polymerized ethylene (PPE:N), is able to inhibit type X collagen expression in committed MSCs. The aim of this study was to determine if the decreased expression of type X collagen, induced by the PPE:N surfaces is maintained when MSCs are removed from the surface and transferred to pellet cultures in the presence of serum and growth factor free chondrogenic media. Human MSCs were obtained from aspirates from the intramedullary canal of donors undergoing total hip replacement for OA. Cells were expanded for 2–3 passages and then cultured on polystyrene dishes and on two different PPE:N surfaces: high (H) and low (L) pressure deposition. Cells were transferred for 7 additional days in chondrogenic serum free media (DMEM high glucose supplemented with 2 mM L-glutamine, 20 mM HEPES, 45 mM NaHCO3, 100 U/ml penicillin, 100 ug/ml streptomycin, 1 mg/ml bovine serum albumin, 5 ug/ml insulin, 50 ug/ml ascorbic acid, 5 ng/ml sodium selenite, 5 ug/ml transferrin) in pellet culture or on PS cell culture dishes. RNA was extracted using a standard TRIzol protocol. RT-PCR was realized using Superscript II (RT) and Taq polymerase (PCR) with primers specific for type I and X collagen. GAPDH was used as a housekeeping gene and served to normalize the results.Purpose
Method
Whilst it is known that oxidative stress can cause early degenerative changes observed in experimental osteoarthritis and that a major drawback of current cartilage and intervertebral disc tissue engineering is that human mesenchymal stem cells (MSCs) from osteoarthritis (OA) patients express type X collagen, a marker of late-stage chondrocyte hypertrophy (associated with endochondral ossification), little is known whether the expression of type X collagen in MSCs from OA patients can be related to oxidative stress or inflammatory reactions that occur during this disease. Human MSCs were obtained from aspirates from the intramedullary canal of donors undergoing total hip replacement for OA. Bone marrow aspirates were processed essentially as previously described. Briefly, non-adherent cells were discarded after 72h of culture and the adherent ones were expanded for 2–3 passages. MSCs from normal donor (control) were obtained from Lonza. Cells were then lysed and protein expression was detected by Western blot using specific antibodies directed against type X collagen, as well as the antioxidant enzymes Mn-superoxide dismutase (MnSOD), catalase (CAT) and glutathione peroxidase-1 (GPx-1) and inflammation related proteins cyclooxygenase-1 (COX-1) and intercellular adhesion molecule-1 (ICAM-1). GAPDH was used as a housekeeping gene and served to normalize the results. Correlations between the expressions of the different proteins were realized using the correlation Z test with StatView (SAS Institute).Purpose
Method
