Clinical data suggest concomitant therapy with bisphosphonates and parathyroid hormone (PTH) may blunt the anabolic effect of PTH; rodent models suggest that infrequently administered bisphosphonates may interact differently. To evaluate the effects of combination therapy with an intravenous infusion of zoledronic acid 5 mg and daily subcutaneous recombinant human (rh)PTH(1-34) (teriparatide) 20 mg versus either agent alone on bone mineral density (BMD) and bone turnover markers, we conducted a 1-year multicenter, multinational, randomized, partial double-blinded, controlled trial. 412 postmenopausal women with osteoporosis (mean age 65 AE 9 years) were randomized to a single infusion of zoledronic acid 5 mg plus daily subcutaneous teriparatide 20 mg (n ¼ 137), zoledronic acid alone (n ¼ 137), or teriparatide alone (n ¼ 138). The primary endpoint was percentage increase in lumbar spine BMD (assessed by dual-energy X-ray absorptiometry [DXA]) at 52 weeks versus baseline. Secondary endpoints included change in BMD at the spine at earlier time points and at the total hip, trochanter, and femoral neck at all time points. At week 52, lumbar spine BMD had increased 7.5%, 7.0%, and 4.4% in the combination, teriparatide, and zoledronic acid groups, respectively ( p < .001 for combination and teriparatide versus zoledronic acid). In the combination group, spine BMD increased more rapidly than with either agent alone ( p < .001 versus both teriparatide and zoledronic acid at 13 and 26 weeks). Combination therapy increased total-hip BMD more than teriparatide alone at all times (all p < .01) and more than zoledronic acid at 13 weeks ( p < .05), with final 52-week increments of 2.3%, 1.1%, and 2.2% in the combination, teriparatide, and zoledronic acid groups, respectively. With combination therapy, bone formation (assessed by serum N-terminal propeptide of type I collagen [PINP]) increased from 0 to 4 weeks, declined minimally from 4 to 8 weeks, and then rose throughout the trial, with levels above baseline from 6 to 12 months. Bone resorption (assessed by serum b-C-telopeptide of type I collagen [b-CTX]) was markedly reduced with combination therapy from 0 to 8 weeks (a reduction of similar magnitude to that seen with zoledronic acid alone), followed by a gradual increase after week 8, with levels remaining above baseline for the latter half of the year. Levels for both markers were significantly lower with combination therapy versus teriparatide alone ( p < .002). Limitations of the study included its short duration, lack of endpoints beyond DXA-based BMD (e.g., quantitative computed tomography and finite-element modeling for bone strength), lack of teriparatide placebo, and insufficient power for fracture outcomes. We conclude that while teriparatide increases spine BMD more than zoledronic acid and zoledronic acid increases hip BMD more than teriparatide, combination therapy provides the largest, most rapid increments when both spine and hip sites are considered. ß
To evaluate whether the sodium-glucose cotransporter 2 inhibitor empagliflozin (EMPA) reduces liver fat content (LFC) in recent-onset and metabolically wellcontrolled type 2 diabetes (T2D). RESEARCH DESIGN AND METHODS Patients with T2D (n 5 84) (HbA 1c 6.6 6 0.5% [49 6 10 mmol/mol], known disease duration 39 6 27 months) were randomly assigned to 24 weeks of treatment with 25 mg daily EMPA or placebo. The primary end point was the difference of the change in LFC as measured with magnetic resonance methods from 0 (baseline) to 24 weeks between groups. Tissue-specific insulin sensitivity (secondary outcome) was assessed by two-step clamps using an isotope dilution technique. Exploratory analysis comprised circulating surrogate markers of insulin sensitivity and liver function. Statistical comparison was done by ANCOVA adjusted for respective baseline values, age, sex, and BMI. RESULTS EMPA treatment resulted in a placebo-corrected absolute change of 21.8% (95% CI 23.4, 20.2; P 5 0.02) and relative change in LFC of 222% (236, 27; P 5 0.009) from baseline to end of treatment, corresponding to a 2.3-fold greater reduction. Weight loss occurred only with EMPA (placebo-corrected change 22.5 kg [23.7, 21.4]; P < 0.001), while no placebo-corrected change in tissue-specific insulin sensitivity was observed. EMPA treatment also led to placebo-corrected changes in uric acid (274 mol/L [2108, 242]; P < 0.001) and high-molecular-weight adiponectin (36% [16, 60]; P < 0.001) levels from 0 to 24 weeks. CONCLUSIONS EMPA effectively reduces hepatic fat in patients with T2D with excellent glycemic control and short known disease duration. Interestingly, EMPA also decreases circulating uric acid and raises adiponectin levels despite unchanged insulin sensitivity. EMPA could therefore contribute to the early treatment of nonalcoholic fatty liver disease in T2D.
This study investigates the effects of kyphoplasty on pain and mobility in patients with osteoporosis and painful vertebral fractures compared with conventional medical management.Introduction: Pharmacological treatment of patients with primary osteoporosis does not prevent pain and impaired activity of patients with painful vertebral fractures. Therefore, we evaluated the clinical outcome after kyphoplasty in patients with vertebral fractures and associated chronic pain for >12 months. Materials and Methods: Sixty patients with primary osteoporosis and painful vertebral fractures presenting for >12 months were included in this prospective, nonrandomized controlled study. Twenty-four hours before performing kyphoplasty, the patients self-determined their inclusion into the kyphoplasty or control group so that 40 patients were treated with kyphoplasty, whereas 20 served as controls. This study assessed changes in radiomorphology, pain visual analog scale (VAS) score, daily activities (European Vertebral Osteoporosis Study [EVOS] score), number of new vertebral fractures, and health care use. Outcomes were assessed before treatment and at 3 and 6 months of follow-up. All patients received standard medical treatment (1g calcium, 1000 IE vitamin D 3 , standard dose of oral aminobisphosphonate, pain medication, physical therapy). Results: Kyphoplasty increased midline vertebral height of the treated vertebral bodies by 12.1%, whereas in the control group, vertebral height decreased by 8.2% (p ס 0.001). Augmentation and internal stabilization by kyphoplasty resulted in a reduction of back pain. VAS pain scores improved in the kyphoplasty group from 26.2 ± 2 to 44.2 ± 3.3 (SD; p ס 0.007) and in the control group from 33.6 ± 4.1 to 35.6 ± 4.1 (not significant), whereas the EVOS score increased in the kyphoplasty group from 43.8 ± 2.4 to 54.5 ± 2.7 (p ס 0.031) and in the control group from 39.8 ± 4.5 to 43.8 ± 4.6 (not significant). The number of back pain-related doctor visits within the 6-month follow-up period decreased significantly after kyphoplasty compared with controls: mean of 3.3 visits/patient in the kyphoplasty group and a mean of 8.6 visits/patient in the control group (p ס 0.0147). Conclusions:The results of this study show significantly increased vertebral height, reduced pain, and improved mobility in patients after kyphoplasty. Kyphoplasty performed in appropriately selected osteoporotic patients with painful vertebral fractures is a promising addition to current medical treatment.
This report describes the first observation of a direct mitogenic effect of androgens on isolated osteoblastic cells in serum-free culture. [3H]thymidine incorporation into DNA and cell counts were used as measures of cell proliferation. The percentage of cells that stained for alkaline phosphatase was used as a measure of differentiation. Dihydrotestosterone (DHT) enhanced mouse osteoblastic cell proliferation in a dose dependent manner over a wide range of doses (10(-8) to 10(-11) molar), and was maximally active at 10(-9) M. DHT also stimulated proliferation in human osteoblast cell cultures and in cultures of the human osteosarcoma cell line, TE89. Testosterone, fluoxymesterone (a synthetic androgenic steroid) and methenolone (an anabolic steroid) were also mitogenic in the mouse bone cell system. The mitogenic effect of DHT on bone cells was inhibited by antiandrogens (hydroxyflutamide and cyproterone acetate) which compete for binding to the androgen receptor. In addition to effects on cell proliferation, DHT increased the percentage of alkaline phosphatase (ALP) positive cells in all three bone cell systems tested, and this effect was inhibited by antiandrogens. We conclude that androgens can stimulate human and murine osteoblastic cell proliferation in vitro, and induce expression of the osteoblast-line differentiation marker ALP, presumably by an androgen receptor mediated mechanism.
Patients with diabetes or hypertension have elevated ET-1 levels, but do not exhibit positive correlations between ET-1 levels and BP, which was observed in healthy controls. Increased ET-1 levels do not induce hypertension in diabetes, but were lower in diabetic patients taking ACE inhibitors compared to those without ACE inhibitors. There is no significant association between ET-1 levels and vascular complications. These findings suggest that the plasma ET-1 level is not a marker of endothelial dysfunction but changes in plasma ET-1 levels may precede vascular complications associated with hypertension and diabetes.
This study investigated the prevalence of the intravertebral vacuum phenomenon (IVP) and osteonecroses in vertebral compression fractures (VCFs). We therefore performed an histological analysis of biopsies obtained from VCFs prior to balloon kyphoplasty. Computed tomography (CT) scans were reviewed regarding the presence of an IVP (i.e. cleft sign, Kümmell disease). We reviewed the data of 266 consecutive patients treated by balloon kyphoplasty in 501 procedures from 2002 to 2004. From 180 patients (68%) we obtained adequate bone tissue for histological evaluation. Biopsy specimens were analysed regarding the presence of osteoporosis, infection, malignancy and osteonecrosis. CT scans of all 180 patients were reviewed for presence of an IVP. Histological examination revealed 135 (75%) osteoporoses, 20 (11%) neoplasms, 12 (7%) trauma cases and 13 (7%) osteonecroses. An IVP was present in 12 (7%) patients. There was a significant association of osteonecrosis and IVP (P < 0.0001). Eleven of 12 patients with a vacuum phenomenon showed an osteonecrosis on histology, whereas 11 of 13 patients with osteonecrosis showed an IVP on CT. The IVP is a specific sign of osteonecrosis in vertebral compression fractures (sensitivity 85%, specificity 99%, positive predictive value 91%). Our findings strongly support the thesis that an IVP indicates local bone ischemia associated with a non-healing vertebral collapse and pseudarthrosis.
Previously, we reported significantly reduced pain and improved mobility persisting for 6 months after kyphoplasty of chronically painful osteoporotic vertebral fractures in the first prospective controlled trial. Since improvement of spinal biomechanics by restoration of vertebral morphology may affect the incidence of fracture, long-term clinical benefit and thereby cost-effectiveness, here we extend our previous work to assess occurrence of new vertebral fractures and clinical parameters 1 year after kyphoplasty compared with a conservatively treated control group. Sixty patients with osteoporotic vertebral fractures due to primary osteoporosis were included: 40 patients were treated with kyphoplasty, 20 served as controls. All patients received standard medical treatment. Morphological characteristics, new vertebral fractures, pain (visual analog scale), physical function [European Vertebral Osteoporosis Study (EVOS) score] (range 0-100 each) and back-pain-related doctors' visits were re-assessed 12 months after kyphoplasty. There were significantly fewer patients with new vertebral fractures of the thoracic and lumbar spine, after 12-months, in the kyphoplasty group than in the control group (P=0.0084). Pain scores improved from 26.2 to 44.4 in the kyphoplasty group and changed from 33.6 to 34.3 in the control group (P=0.008). Kyphoplasty treated patients required a mean of 5.3 back-pain-related doctors' visits per patient compared with 11.6 in the control group during 12 months follow-up (P=0.006). Kyphoplasty as an addition to medical treatment and when performed in appropriately selected patients by an interdisciplinary team persistently improves pain and reduces occurrence of new vertebral fractures and healthcare utilization for at least 12 months in individuals with primary osteoporosis.
Angiogenesis is indispensable during fracture repair, and vascular endothelial growth factor (VEGF) is critical in this process. CCN1 (CYR61) is an extracellular matrix signaling molecule that has been implicated in neovascularization through its interactions with several endothelial integrin receptors. CCN1 has been shown to be up-regulated during the reparative phase of fracture healing; however, the role of CCN1 therein remains unclear. Here, the regulation of CCN1 expression in osteoblasts and the functional consequences thereof were studied. Stimulation of osteoblasts with VEGF resulted in a dose-and time-dependent up-regulation of CCN1 mRNA and protein. An up-regulation of both cell surface-associated CCN1 as well as extracellular matrix-associated CCN1 in osteoblasts was found. The supernatant of VEGF-prestimulated osteoblasts was chemotactic for endothelial cells, increasing their migration and stimulated capillary-like sprout formation. These effects could be attributed to the presence of CCN1 in the osteoblast supernatant as they were prevented by an antibody against CCN1 or by small interfering RNA-mediated knockdown of osteoblast CCN1. Moreover, the supernatant of VEGF-prestimulated osteoblasts induced angiogenesis in Matrigel plugs in vivo in a CCN1-dependent manner. In addition, blockade of CCN1 prevented bone fracture healing in mice. Taken together, the present work demonstrates a potential paracrine loop consisting of the VEGF-mediated up-regulation of CCN1 in osteoblasts that attracts endothelial cells and promotes angiogenesis. Such a loop could be operative during fracture healing.
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