Changes in Dkk-1, sclerostin, and RANKL serum levels following discontinuation of long-term denosumab treatment in postmenopausal women.

PURPOSE: The positive effects of denosumab (DMAb) on bone mineral density (BMD) are quickly reversible after its discontinuation. We investigated whether this rebound was associated with dysregulation of the Wnt canonical pathway and/or by the increase in the receptor-activator of nuclear factor-kappa B ligand (RANKL) serum levels. METHODS: The study included patients (n = 15) with postmenopausal osteoporosis to whom DMAb was administered for 78 months and then discontinued. We collected BMD data at baseline/month 0 (M0), M60, M84 (6 months after last DMAb administration, coinciding when the next DMAb dose would typically be due), and after 3 and 12 months of follow-up (FU-M3 and FU-M12, respectively). Serum C-terminal telopeptide of type 1 collagen (CTX-I), Dickkopf-1 (Dkk-1), and sclerostin were measured at M0, M60, M84, FU-M3, and FU-M12. Serum N-terminal propeptide of type 1 procollagen (PINP) and RANKL were dosed at M60, M84, FU-M3, and FU-12. RESULTS: We found a significant decrease in the T-score at all sites at FU-M12, when compared to M84 (-0.51 ±â€¯0.91 at the lumbar spine; -0.72 ±â€¯0.33 at the total hip; and -0.42 ±â€¯0.27 at the femoral neck, p < 0.05). After DMAb discontinuation (M84 vs FU M12) CTX-I, PINP increased already at FU-M3 (+0.921 ±â€¯0.482 ng/mL, +126.60 ±â€¯30.36 ng/mL, respectively, p < 0.01), RANKL increased at FU-M12 (+0.041 ±â€¯0.062 ng/mL, p < 0.05), while Dkk-1 and sclerostin decreased at FU-M12 (-10.90 ±â€¯11.80 and - 13.00 ±â€¯10.52 pmol/L, respectively, p < 0.01). No changes in BMD or any of the markers were found between M60 and M84. CONCLUSIONS: RANKL serum levels progressively increased after discontinuation of long-term DMAb while Dkk-1 and sclerostin serum levels decreased. The increase in RANKL serum levels supports the hypothesis of a sudden loss of inhibition of the resting osteoclast line after DMAb clearance, with a hyperactivation of these cells. Our results suggest that the changes in serum Wnt inhibitors after DMAb suspension might represent a mere feedback response to the increased bone turnover.

Inhibition of tumor necrosis factor-alpha (TNF-alpha) in patients with early rheumatoid arthritis results in acute changes of bone modulators.

OBJECTIVE: Dicckopf-1 (Dkk-1) is a potent inhibitor of the Wnt canonical pathway. In rheumatoid arthritis (RA), Dkk-1 is upregulated by tumor necrosis factor-α (TNF). Certolizumab pegol (CMZ) is a biologic TNF-inhibitor (TNFi) effective in RA and slows radiographic progression. Data on the immediate effects (≤1-8 weeks) of TNFi on Wnt modulators are lacking. This study investigated the acute influence of TNFi treatment on Wnt modulators (Dkk-1 and sclerostin) and bone turnover markers (BTM), including intact N-terminal propeptide of collagen type I (PINP) and C-terminal telopeptide of type I collagen (CTX-I). METHODS: This longitudinal, uncontrolled study involved female RA patients with inadequate response to conventional methotrexate who underwent treatment with CMZ. ESR, Dkk-1, sclerostin, BTM, parathyroid hormone (PTH), and 25OH-vitamin D levels were evaluated at baseline, week 1, week 4, and week 8. Radiographs of the hands and feet were obtained at baseline and the total and erosion scores were assessed using the Simple Erosion Narrowing Score method (SENS). RESULTS: Seventeen patients were enrolled. Dkk-1 and CTX-I significantly decreased after one week of treatment with CMZ (-49.1 ±â€¯17.1% and -25.0 ±â€¯20.6%, respectively, p < 0.01), whereas PINP increased (+43.2 ±â€¯31.5%, p < 0.01). These changes persisted at week 4 and 8. CONCLUSIONS: Our study showed that TNF-alpha inhibition with CMZ promptly results in a rapid decline of serum Dkk-1 levels, alongside decreased bone resorption and increased bone formation.

Malnutrition and sarcopenia in a large cohort of patients with systemic sclerosis.

Systemic sclerosis (SSc) is an autoimmune disease which may lead to malnutrition. Previous studies have defined it with different criteria. No thorough evaluations of sarcopenia in SSc are available. The aim of the present study was to assess the prevalence and the potential association of malnutrition and sarcopenia in a large cohort of SSc cases. A total of 141 SSc consecutive outpatients were enrolled. Body composition was analyzed by densitometry. Malnutrition was defined according to recently published ESPEN criteria, whereas sarcopenia was diagnosed in patients with reduced skeletal muscle index. Malnutrition was diagnosed in 9.2% of patients (95% CI, 4.4-14.0%). Malnourished patients had worse gastrointestinal symptoms according to UCLA SCTC GIT 2.0 questionnaire (p = 0.007), lower physical activity (p = 0.028), longer disease duration (p = 0.019), worse predicted DLCO/VA and FVC (p = 0.009, respectively), worse disease severity according to Medsger severity score (p < 0.001), lower hemoglobin (p = 0.023), and fat-free mass (p < 0.001) and were more often sarcopenic (p < 0.001). In multivariate analysis, only FVC (p = 0.006) and disease severity (p = 0.003), in particular for the lungs (p = 0.013), were confirmed to be worse in malnourished patients. Sarcopenia was diagnosed in 29\140 patients (20.7%; 95% CI, 14.0-27.4%); 11\29 were also malnourished. In multivariate analysis, sarcopenic patients had longer disease duration (p = 0.049), worse DLCO/VA (p = 0.002), and lung (p = 0.006) and skin (p = 0.014) involvement. In SSc, malnutrition defined with ESPEN criteria was found to be lower than previously reported. Sarcopenia was found to be somewhat common. Lung involvement was significantly associated with nutritional status and may not be explained only by muscle weakness.