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The WP9QY peptide (W9) consists of nine amino acids. It binds to RANKL and blocks RANKL-induced increases in bone resorption and osteoclastogenesis. W9 has a unique effect on the coupling mechanism between osteoclasts and osteoblasts, which promotes bone formation while working to suppress bone resorption. In this study, with the aim of clinical application of W9 for fracture treatment, we aimed to clarify the bone repair-promoting effect of W9 when administered locally to a rat femur model of delayed union. Using Sprague-Dawley rats, a model of delayed union was created in the right femur by cauterizing the periosteum. Injection of W9 (1 mg in 100 μl) or phosphate-buffered saline (PBS) (100 μl) at the fracture site was performed at the operation and every week thereafter until death (sacrifice). The bone union rate was 14% in the PBS group and 57% in the W9 group at 8 weeks postoperatively. The X-ray score of the W9 group was significantly higher than that of the PBS group at 8 weeks postoperatively. When bone morphometry was analyzed by micro-computed tomography (CT), total callus volume (TV) and mineralized callus bone volume (BV) were measured. TV showed no significant difference between the two groups, but BV/TV was significantly higher in the W9 group. This finding suggests that local administration of W9 can promote bone maturation from callus and can be considered to contribute to fracture healing. These results reveal that W9 has an effect on fractures of promoting healing and could be applied as a fracture treatment. [ABSTRACT FROM AUTHOR]

Aiming to increase the content of type 2 collagen in scaffold-free cartilage-like cell sheets prepared using human bone marrow mesenchymal stem cells, the effect of several kinds of additives in a chondrogenic medium was investigated. Addition of ascorbic acid 2 phosphate (VCP) at a high concentration (250 µg/ml) and type 1 atelocollagen (5 µg/ml) increased the accumulation of type 2 collagen by fourfold and twofold, respectively. On the other hand, an antioxidant, glutathione showed no such effect. The synergistic effect of VCP and type 1 atelocollagen resulted in an eightfold increase in the accumulation level of type 2 collagen. Furthermore, the gene expression level of type 2 collagen increased and that of matrix metalloproteinase-13 (MMP-13) decreased to approximately one-third of the control. The increase in type 2 collagen accumulation in the scaffold-free cartilage-like cell sheet might be due to not only the enhancement of the synthesis but also the suppression of the degradation of type 2 collagen by MMP-13. [ABSTRACT FROM AUTHOR]

With the aim to utilize human mesenchymal stem cells (hMSCs) grown in large scale for regenerative medicine, effects of agitation rate on aggregation during beads-to-beads subcultivation of microcarrier culture of hMSCs were studied. hMSCs could attach and grew on surface-type microcarriers of Cytodex 1, whereas almost no cell elongation and growth were observed on porous type microcarriers of Cytopores. The percentages of aggregated Cytodex 1 microcarriers at an agitation rate of 60 and 90 rpm were lower than that at 30 rpm, which was the lowest agitation rate necessary for the suspension of Cytodex 1 microcarriers, and the cells grew fastest at 60 rpm. hMSC could be subcultivated on Cytodex 1 by the beads-to-beads method at both 30 and 60 rpm without trypsinization. However, agitation at 60 rpm resulted in a markedly lower percentage of aggregated microcarriers not only before but also after subcultivation. The percentages of CD90- and CD166-positive cells among cells grown on Cytodex 1 at 60 rpm (91.5 and 87.6 %) were comparable to those of cells grown in the pre-culture on dishes. In conclusion, hMSCs could be subcultivated on Cytodex 1 by beads-to-beads method maintaining the expressions of the cell surface antigens CD90 and CD166, while adjusting agitation rate could decrease the microcarrier aggregation. [ABSTRACT FROM AUTHOR]

Predicting the responses of patients with rheumatoid arthritis (RA) to tocilizumab is difficult, because inflammatory markers such as C-reactive protein rapidly normalize regardless of clinical efficacy. We aimed to identify factors that could predict response to tocilizumab. Sixty-five patients completed 52 weeks of tocilizumab therapy. Serum fibrinogen, D-dimer and interleukin (IL)-1β levels were measured at baseline and after 4 weeks of therapy. Clinical responses to tocilizumab were assessed using disease activity score 28-erythrocyte sedimentation rate and the clinical disease activity index at baseline and after 52 weeks of therapy (UMIN Clinical Trials Registry No. UMIN000002246). Mean age was 60.5 years (range 22-85 years). Mean disease duration was 11.2 years (range 0-45 years). All patients had moderate-to-severe disease activity and were resistant to disease-modifying anti-rheumatic drugs and/or other biologics. Baseline IL-1β levels were significantly lower in responders than in non-responders ( p = 0.045), but multiple logistic regression analysis found no significant difference (adjusted odds ratio 2.74; 95 % confidence interval 0.84-8.95; p = 0.096). Low D-dimer and IL-1β levels at 4 weeks predicted greater decrease in disease activity after 52 weeks of treatment ( p = 0.005 and p < 0.001, respectively). Effects of tocilizumab at 52 weeks could be predicted from D-dimer and IL-1β levels after 4 weeks of tocilizumab treatment. These markers might be more useful than current inflammatory markers for early-stage prediction of response to tocilizumab in RA. [ABSTRACT FROM AUTHOR]

We investigated the effects of biologics for rheumatoid arthritis (RA) patients on bone mineral density (BMD) and bone metabolic markers (BMM), retrospectively, and also clarified the effects of bisphosphonates (alendronate or risedronate 35 mg/week) and glucocorticoids. Participants in this study comprised 219 patients with RA, including 117 patients treated with biologics (infliximab, n = 90; etanercept, n = 27) and 102 patients with conventional disease-modifying anti-rheumatic drugs (DMARDs) for 1 year. Changes in BMD at the lumbar spine and total hip and BMMs [urinary type I collagen cross-linked N-telopeptide (NTX) and bone-specific alkaline phosphatase] were measured. BMD of the lumbar spine in both groups and total hip BMD in the biologics group were unchanged during treatment with biologics. However, BMD of the total hip was significantly decreased in the DMARDs group (from 0.731 ± 0.135 to 0.706 ± 0.135 g/cm). Patients receiving glucocorticoids without bisphosphonates showed significant decrease in BMD of the total hip compared with patients not receiving glucocorticoids or receiving glucocorticoids with bisphosphonates in both biologics and DMARDs groups. Furthermore, BMD of the lumbar spine increased ( p < 0.05) for patients in the biologics group who received bisphosphonates. NTX was significantly decreased only in the biologics group. Multiple regression analysis showed that BMD and bone metabolic marker levels correlated positively with bisphosphonate and biologics use and negatively with glucocorticoid use. BMD of the total hip was maintained in the patients using biologics without glucocorticoids or with bisphosphonates, but it was not maintained in the DMARDs patients, even without glucocorticoids or with bisphosphonates. Even if biologics have protective effect against bone loss of RA patients, we should consider reducing the dose of glucocorticoids and adding bisphosphonates for the treatment of osteoporosis. [ABSTRACT FROM AUTHOR]