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Abstract
Although endogenous glucocorticoids (GCs) are important regulators of bone integrity and the immune system, their role in bone repair after fracture-a process highly dependent on inflammation and bone formation-is unclear. Because most effects of GCs are mediated by the glucocorticoid receptor (GR), we used an inducible global GR knockout (GRgtROSACreERT2) mouse model to eliminate endogenous GC action in all cells contributing to bone repair. The healing process was analyzed by cytokine/chemokine multiplex analysis, flow cytometry, histology, gene-expression analysis, microcomputed tomography, and biomechanical analysis. We observed increased early systemic and local inflammatory responses, as well as a significantly higher number of T cells infiltrating the fracture callus. Later in the healing process, we found impaired endochondral ossification in the absence of the GR, leading to persistent cartilage in the calli of the GRgtROSACreERT2 mice, decreased bending stiffness, and a significantly lower proportion of healed bones. Collectively, our data show that the absence of the GR significantly impairs fracture healing associated with a defective cartilage-to-bone transition, underscoring an important role of GCs during fracture healing.-Rapp, A. E., Hachemi, Y., Kemmler, J., Koenen, M., Tuckermann, J., Ignatius, A. Induced global deletion of glucocorticoid receptor impairs fracture healing.
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Abstract
ZusammenfassungVenöse Rezirkulationskreisläufe mit daraus resultierender kapillärer Hypertension beeinflussen möglicherweise den oxidativen Stoffwechsel der Skelettmuskulatur. Ziel dieser Studie war, den Einfluss der chronischen venösen Insuffizienz (CVI) und deren Therapie durch medizinische Kompressionstrümpfe auf Leistung, Laktatspiegel und subjektives Befinden von Langstreckenläufern und Radsportlern zu untersuchen. Studienteilnehmer, Methoden: 24 gesunde Läufer (13 Männer und 11 Frauen) und 20 gesunde Radsportler (18 Männer und 2 Frauen) wurden in einer offenen prospektiven, randomisierten Kohortenstudie über 40 Tage untersucht. Die venöse Insuffiziez der Läufer entsprach Stadium C2–4EC,P,SAS,PPR, die der Radsportler C2–3EPAS,PPR. Die Kompressionstherapie erfolgte mit Unterschenkelkompressionsstrümpfen nach Maß (Venotrain Champion A-D compression class 2, Bauerfeind Germany). Standardisierte Laufbandergometer- bzw. Fahrradergometer-Mehrstufentests mit Bestimmung der kapillären Laktatspiegel wurden durchgeführt und subjektive Beschwerden pro- und retrospektiv mittels Fragebögen erhoben. Ergebnisse: Die medizinische Kompressionstherapie führte zu keinem akuten Effekt auf Leistung, Herzfrequenz und Laktatspiegel, wenn Leistungstests mit und ohne Kompression verglichen wurden. Ebensowenig fand sich kein signifikanter Unterschied zwischen Leistungstests ohne Kompression vor und mit Kompression nach einer vierwöchigen Kompressionstherapie. Die Kompressiontherapie führte jedoch zu einer signifikanten Abnahme von CVI-typischen Beschwerden im Alltag und nach dem Training. Schlussfolgerung: Bei Läufern und Radfahrern mit CVI konnte keine messbare Leistungssteigerung nach einer akuten oder mehrwöchigen Therapie mit Kompressionstrümpfen nachgewiesen werden. Ebensowenig wurde die sportliche Leistungsfähigkeit durch die Kompressionstherapie beeinträchtigt. Subjektiv empfanden die Athleten das Tragen von Kompressionsstrümpfen als sehr vorteilhaft. Kompressionstrümpfe können Athleten mit CVI daher empfohlen werden.
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Mast Cells Are Critical Regulators of Bone Fracture-Induced Inflammation and Osteoclast Formation and Activity. J Bone Miner Res 2017; 32:2431-2444. [PMID: 28777474 DOI: 10.1002/jbmr.3234] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 07/27/2017] [Accepted: 08/02/2017] [Indexed: 12/25/2022]
Abstract
Mast cells, important sensor and effector cells of the immune system, may influence bone metabolism as their number is increased in osteoporotic patients. They are also present during bone fracture healing with currently unknown functions. Using a novel c-Kit-independent mouse model of mast cell deficiency, we demonstrated that mast cells did not affect physiological bone turnover. However, they triggered local and systemic inflammation after fracture by inducing release of inflammatory mediators and the recruitment of innate immune cells. In later healing stages, mast cells accumulated and regulated osteoclast activity to remodel the bony fracture callus. Furthermore, they were essential to induce osteoclast formation after ovariectomy. Additional in vitro studies revealed that they promote osteoclastogenesis via granular mediators, mainly histamine. In conclusion, mast cells are redundant in physiologic bone turnover but exert crucial functions after challenging the system, implicating mast cells as a potential target for treating inflammatory bone disorders. © 2017 American Society for Bone and Mineral Research.
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C5aR inhibition in the early inflammatory phase does not affect bone regeneration in a model of uneventful fracture healing. Eur J Med Res 2016; 21:42. [PMID: 27784330 PMCID: PMC5081665 DOI: 10.1186/s40001-016-0236-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 10/16/2016] [Indexed: 01/06/2023] Open
Abstract
Background Recent studies were able to demonstrate involvement of the complement cascade in bone biology. Further studies analyzed the role of complement in traumatic injuries and demonstrated negative effects after excessive systemic activation of the inflammatory response with early abrogation of complement activation after application of a C5aR-antagonist exerting beneficial effects upon bone regeneration. In contrast, own fracture healing experiments with complement-deficient animals implied a crucial role of the complement cascade for sufficient fracture healing. Methods To analyze the effect of a short abrogation of the complement system in the local process of fracture healing, a fracture healing experiment with wild-type mice (C57BL6), femoral osteotomy, consecutive external fixation for 21 days and blockade of the early complement activation (C5aRA) directly after trauma and after 12 h was performed. Control animals received a peptide without any biological effects. After 1–3 days, the inflammatory response was monitored with IL-6 immunostaining, serum analyses of C5a and after 3 days with histological evaluation of PMN. Fracture healing was examined with biomechanical, radiological and histological methods after 21 days. Results While a decrease of the early inflammatory response was seen on day 1 of the C5aRA-treated group regarding immunostaining for IL-6 and after 3 days in the histological evaluation of PMN, no significant differences were demonstrated between both experimental groups after 21 days in the biomechanical, radiological and histological evaluation. Conclusions The present results demonstrate that the short-term inhibition of complement activation immediately after fracture does not significantly affect bone regeneration in an experimental model of regular fracture healing. Whereas other studies demonstrated that the early posttraumatic blockade of the C5aR improves fracture healing in a scenario of combined trauma, the present findings implicate that the same treatment has no effect in uneventful bone healing.
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Abstract
The heparin-binding growth and differentiation factor midkine (Mdk) is proposed to negatively regulate osteoblast activity and bone formation in the adult skeleton. As Mdk-deficient mice were protected from ovariectomy (OVX)-induced bone loss, this factor may also play a role in the pathogenesis of postmenopausal osteoporosis. We have previously demonstrated that Mdk negatively influences bone regeneration during fracture healing. Here, we investigated whether the inhibition of Mdk using an Mdk-antibody (Mdk-Ab) improves compromised bone healing in osteoporotic OVX-mice. Using a standardized femur osteotomy model, we demonstrated that Mdk serum levels were significantly enhanced after fracture in both non-OVX and OVX-mice, however, the increase was considerably greater in osteoporotic mice. Systemic treatment with the Mdk-Ab significantly improved bone healing in osteoporotic mice by increasing bone formation in the fracture callus. On the molecular level, we demonstrated that the OVX-induced reduction of the osteoanabolic beta-catenin signaling in the bony callus was abolished by Mdk-Ab treatment. Furthermore, the injection of the Mdk-Ab increased trabecular bone mass in the skeleton of the osteoporotic mice. These results implicate that antagonizing Mdk may be useful for the therapy of osteoporosis and osteoporotic fracture-healing complications.
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Exposure to 100% Oxygen Abolishes the Impairment of Fracture Healing after Thoracic Trauma. PLoS One 2015; 10:e0131194. [PMID: 26147725 PMCID: PMC4492600 DOI: 10.1371/journal.pone.0131194] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 05/30/2015] [Indexed: 12/22/2022] Open
Abstract
In polytrauma patients a thoracic trauma is one of the most critical injuries and an important trigger of post-traumatic inflammation. About 50% of patients with thoracic trauma are additionally affected by bone fractures. The risk for fracture malunion is considerably increased in such patients, the pathomechanisms being poorly understood. Thoracic trauma causes regional alveolar hypoxia and, subsequently, hypoxemia, which in turn triggers local and systemic inflammation. Therefore, we aimed to unravel the role of oxygen in impaired bone regeneration after thoracic trauma. We hypothesized that short-term breathing of 100% oxygen in the early post-traumatic phase ameliorates inflammation and improves bone regeneration. Mice underwent a femur osteotomy alone or combined with blunt chest trauma 100% oxygen was administered immediately after trauma for two separate 3 hour intervals. Arterial blood gas tensions, microcirculatory perfusion and oxygenation were assessed at 3, 9 and 24 hours after injury. Inflammatory cytokines and markers of oxidative/nitrosative stress were measured in plasma, lung and fracture hematoma. Bone healing was assessed on day 7, 14 and 21. Thoracic trauma induced pulmonary and systemic inflammation and impaired bone healing. Short-term exposure to 100% oxygen in the acute post-traumatic phase significantly attenuated systemic and local inflammatory responses and improved fracture healing without provoking toxic side effects, suggesting that hyperoxia could induce anti-inflammatory and pro-regenerative effects after severe injury. These results suggest that breathing of 100% oxygen in the acute post-traumatic phase might reduce the risk of poorly healing fractures in severely injured patients.
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H2S during circulatory shock: some unresolved questions. Nitric Oxide 2014; 41:48-61. [PMID: 24650697 PMCID: PMC4229245 DOI: 10.1016/j.niox.2014.03.163] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 02/10/2014] [Accepted: 03/06/2014] [Indexed: 12/12/2022]
Abstract
Numerous papers have been published on the role of H2S during circulatory shock. Consequently, knowledge about vascular sulfide concentrations may assume major importance, in particular in the context of "acute on chronic disease", i.e., during circulatory shock in animals with pre-existing chronic disease. This review addresses the questions (i) of the "real" sulfide levels during circulatory shock, and (ii) to which extent injury and pre-existing co-morbidity may affect the expression of H2S producing enzymes under these conditions. In the literature there is a huge range on sulfide blood levels during circulatory shock, in part as a result of the different analytical methods used, but also due to the variable of the models and species studied. Clearly, some of the very high levels reported should be questioned in the context of the well-known H2S toxicity. As long as "real" sulfide levels during circulatory shock are unknown and/or undetectable "on line" due to the lack of appropriate techniques, it appears to be premature to correlate the measured blood levels of hydrogen sulfide with the severity of shock or the H2S therapy-related biological outcomes. The available data on the tissue expression of the H2S-releasing enzymes during circulatory shock suggest that a "constitutive" CSE expression may play a crucial role of for the maintenance of organ function, at least in the kidney. The data also indicate that increased CBS and CSE expression, in particular in the lung and the liver, represents an adaptive response to stress states.
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New Process Technologies for the Deposition of Semiconducting Metal Oxide Nanoparticles for Sensing. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.proeng.2014.11.257] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Portals for arthroscopy of the trapeziometacarpal joint. JOURNAL OF HAND SURGERY (EDINBURGH, SCOTLAND) 1997; 22:574-5. [PMID: 9752905 DOI: 10.1016/s0266-7681(97)80347-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have studied the anatomy of the structures superficial to the trapeziometacarpal joint in cadavers in order to define safe entry points for arthroscopy of the joint.
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Electron emission following the interaction of highly charged ions with a Pt(110) target. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1993; 48:3731-3740. [PMID: 9910044 DOI: 10.1103/physreva.48.3731] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Excitation of target Auger-electron emission by the impact of highly charged ions: N6+, O7+, and Ne9+ on Pt(110). PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1992; 46:4003-4011. [PMID: 9908596 DOI: 10.1103/physreva.46.4003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Simulation of convoy-electron emission. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1992; 45:R2655-R2658. [PMID: 9907380 DOI: 10.1103/physreva.45.r2655] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Continuum electrons in coincidence with the charge state of target ions. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1991; 44:4407-4411. [PMID: 9906480 DOI: 10.1103/physreva.44.4407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Theory of the l-state population of Rydberg states formed in ion-solid collisions. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1991; 44:2993-3000. [PMID: 9906299 DOI: 10.1103/physreva.44.2993] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Search for nuclear fusion in deuterated targets under cluster-beam impact. PHYSICAL REVIEW LETTERS 1990; 65:621-624. [PMID: 10042970 DOI: 10.1103/physrevlett.65.621] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Secondary-electron yields from thin foils: A possible probe for the electronic stopping power of heavy ions. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1990; 41:2521-2535. [PMID: 9903385 DOI: 10.1103/physreva.41.2521] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Experimental study of molecular and cluster effects in secondary electron emission. PHYSICAL REVIEW. B, CONDENSED MATTER 1990; 41:3959-3967. [PMID: 9994214 DOI: 10.1103/physrevb.41.3959] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Transport of fast electrons through thin foils. PHYSICAL REVIEW. A, ATOMIC, MOLECULAR, AND OPTICAL PHYSICS 1990; 41:1435-1443. [PMID: 9903238 DOI: 10.1103/physreva.41.1435] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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Isolation and growth of a bacterium able to degrade nitrilotriacetic acid under denitrifying conditions. Biodegradation 1990; 1:31-41. [PMID: 1368140 DOI: 10.1007/bf00117049] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
A Gram-negative bacterium was isolated from river sediment which was able to grow with nitrilotriacetic acid as a combined carbon, nitrogen and energy source in the absence of molecular oxygen using nitrate as the terminal electron acceptor. Batch growth parameters and mass balances are reported for growth under both aerobic and denitrifying conditions. The strain was characterized with respect to its substrate spectrum and other physiological properties. This denitrifying isolate is serologically unrelated to the comprehensively described Gram-negative obligately aerobic NTA-degrading bacteria all of which belong to the alpha-subclass of Proteobacteria. Chemotaxonomic characterization, which revealed the presence of spermidine as the main polyamine and ubiquinone Q-8, excludes the new isolate from the phylogenetically redefined genus Pseudomonas and indicates a possible location within the gamma-subclass of Proteobacteria close to, but separate from the genus Xanthomonas.
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Successful treatment of metastatic renal cell carcinoma with a biologically active dose of recombinant interferon-gamma. J Clin Oncol 1989; 7:1875-84. [PMID: 2511277 DOI: 10.1200/jco.1989.7.12.1875] [Citation(s) in RCA: 104] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
We tested the clinical efficacy of a biologically active dose (BAD) of interferon (IFN)-gamma for treatment of progressive renal cell carcinoma (RCC). Twenty-two RCC patients with disease progression subsequent to nephrectomy were entered on a phase II clinical trial. During an initial dose-finding phase, biochemical responses to repeated once-weekly subcutaneous injections of 10, 100, or 500 micrograms of recombinant IFN-gamma were tested in 16 patients. Results indicated that 100 micrograms IFN-gamma applied once weekly was biologically active with induction of serum beta 2-microglobulin and neopterin. Such a dose induced a nearly maximum response of both markers lasting more than 4 days. This dose was also associated with minimal side effects. A dose of 100 micrograms IFN-gamma given once weekly was, therefore, subsequently given weekly for long-term treatment. During a median time of therapy of 10 months (range, 2 to 32 months) two complete (CR; 20+, 20+ months) and four partial tumor responses (PR; 6+, 7+, 8+, 24+ months) were seen (30% CR plus PR; 95% confidence limits, 12% to 54%) among 20 patients evaluable for response. Patients with refractory disease had significantly lower IFN-gamma-induced increments of serum beta 2-microglobulin than those who achieved clinical remission or stable disease.
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Secondary-electron yield as a probe of preequilibrium stopping power of heavy ions colliding with solids. PHYSICAL REVIEW. A, GENERAL PHYSICS 1989; 40:3632-3636. [PMID: 9902575 DOI: 10.1103/physreva.40.3632] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Secondary electron emission from thin foils under fast-ion bombardment. PHYSICAL REVIEW. B, CONDENSED MATTER 1989; 39:6316-6320. [PMID: 9947264 DOI: 10.1103/physrevb.39.6316] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Temperature-dependent secondary electron yield from ion bombardment of gold and copper oxide superconductors. PHYSICAL REVIEW. B, CONDENSED MATTER 1988; 38:9224-9226. [PMID: 9945718 DOI: 10.1103/physrevb.38.9224] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
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Heavy-ion-induced shock electrons from sputter-cleaned solid surfaces. PHYSICAL REVIEW LETTERS 1987; 58:1773-1775. [PMID: 10034532 DOI: 10.1103/physrevlett.58.1773] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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