Changes in Cartilage Biomarker Levels During a Transcontinental Multistage Footrace Over 4486 km

Cartilage turnover and load-induced tissue changes are frequently assessed by quantifying concentrations of cartilage biomarkers in serum. To date, information on the effects of ultramarathon running on articular cartilage is scarce.; Serum concentrations of cartilage oligomeric matrix protein (COMP), matrix metalloproteinase (MMP)-1, MMP-3, MMP-9, COL2-3/4C long mono (C2C), procollagen type II C-terminal propeptide (CPII), and C2C:CPII will increase throughout a multistage ultramarathon.; Descriptive laboratory study.; Blood samples were collected from 36 runners (4 female; mean age, 49.0 ± 10.7 years; mean body mass index, 23.1 ± 2.3 kg/m2 [start] and 21.4 ± 1.9 kg/m2 [finish]) before (t0) and during (t1: 1002 km; t2: 2132 km; t3: 3234 km; t4: 4039 km) a 4486-km multistage ultramarathon. Serum COMP, MMP-1, MMP-3, MMP-9, C2C, and CPII levels were assessed using commercial enzyme-linked immunosorbent assays. Linear mixed models were used to detect significant changes in serum biomarker levels over time with the time-varying covariates of body weight, running speed, and daily running time.; Serum concentrations of COMP, MMP-9, and MMP-3 changed significantly throughout the multistage ultramarathon. On average, concentrations increased during the first measurement interval (MI1: t1-t0) by 22.5% for COMP (95% CI, 0.29-0.71 ng/mL), 22.3% for MMP-3 (95% CI, 0.24-15.37 ng/mL), and 95.6% for MMP-9 (95% CI, 81.7-414.5 ng/mL) and remained stable throughout MI2, MI3, and MI4. Serum concentrations of MMP-1, C2C, CPII, and C2C:CPII did not change significantly throughout the multistage ultramarathon. Changes in MMP-3 were statistically associated with changes in COMP throughout the ultramarathon race (MMP-3: Wald Z = 3.476, P = .001).; Elevated COMP levels indicate increased COMP turnover in response to extreme running, and the association between load-induced changes in MMP-3 and changes in COMP suggests the possibility that MMP-3 may be involved in the degradation of COMP.; These results suggest that articular cartilage is able to adapt even to extreme physical activity, possibly explaining why the risk of degenerative joint disease is not elevated in the running population

Changes in Cartilage Biomarker Levels During a Transcontinental Multistage Footrace Over 4486 km

Cartilage turnover and load-induced tissue changes are frequently assessed by quantifying concentrations of cartilage biomarkers in serum. To date, information on the effects of ultramarathon running on articular cartilage is scarce.; Serum concentrations of cartilage oligomeric matrix protein (COMP), matrix metalloproteinase (MMP)-1, MMP-3, MMP-9, COL2-3/4C long mono (C2C), procollagen type II C-terminal propeptide (CPII), and C2C:CPII will increase throughout a multistage ultramarathon.; Descriptive laboratory study.; Blood samples were collected from 36 runners (4 female; mean age, 49.0 ± 10.7 years; mean body mass index, 23.1 ± 2.3 kg/m2 [start] and 21.4 ± 1.9 kg/m2 [finish]) before (t0) and during (t1: 1002 km; t2: 2132 km; t3: 3234 km; t4: 4039 km) a 4486-km multistage ultramarathon. Serum COMP, MMP-1, MMP-3, MMP-9, C2C, and CPII levels were assessed using commercial enzyme-linked immunosorbent assays. Linear mixed models were used to detect significant changes in serum biomarker levels over time with the time-varying covariates of body weight, running speed, and daily running time.; Serum concentrations of COMP, MMP-9, and MMP-3 changed significantly throughout the multistage ultramarathon. On average, concentrations increased during the first measurement interval (MI1: t1-t0) by 22.5% for COMP (95% CI, 0.29-0.71 ng/mL), 22.3% for MMP-3 (95% CI, 0.24-15.37 ng/mL), and 95.6% for MMP-9 (95% CI, 81.7-414.5 ng/mL) and remained stable throughout MI2, MI3, and MI4. Serum concentrations of MMP-1, C2C, CPII, and C2C:CPII did not change significantly throughout the multistage ultramarathon. Changes in MMP-3 were statistically associated with changes in COMP throughout the ultramarathon race (MMP-3: Wald Z = 3.476, P = .001).; Elevated COMP levels indicate increased COMP turnover in response to extreme running, and the association between load-induced changes in MMP-3 and changes in COMP suggests the possibility that MMP-3 may be involved in the degradation of COMP.; These results suggest that articular cartilage is able to adapt even to extreme physical activity, possibly explaining why the risk of degenerative joint disease is not elevated in the running population

Automatic detection of the carotid artery boundary on cross-sectional MR image sequences using a circle model guided dynamic programming

Systematic aerobe training has positive effects on the compliance of dedicated arterial walls. The adaptations of the arterial structure and function are associated with the blood flow-induced changes of the wall shear stress which induced vascular remodelling via nitric oxide delivered from the endothelial cell. In order to assess functional changes of the common carotid artery over time in these processes, a precise measurement technique is necessary. Before this study, a reliable, precise, and quick method to perform this work is not present

A novel role of sphingosine 1-phosphate receptor S1pr1 in mouse thrombopoiesis

Millions of platelets are produced each hour by bone marrow (BM) megakaryocytes (MKs). MKs extend transendothelial proplatelet (PP) extensions into BM sinusoids and shed new platelets into the blood. The mechanisms that control platelet generation remain incompletely understood. Using conditional mutants and intravital multiphoton microscopy, we show here that the lipid mediator sphingosine 1-phosphate (S1P) serves as a critical directional cue guiding the elongation of megakaryocytic PP extensions from the interstitium into BM sinusoids and triggering the subsequent shedding of PPs into the blood. Correspondingly, mice lacking the S1P receptor S1pr1 develop severe thrombocytopenia caused by both formation of aberrant extravascular PPs and defective intravascular PP shedding. In contrast, activation of S1pr1 signaling leads to the prompt release of new platelets into the circulating blood. Collectively, our findings uncover a novel function of the S1P-S1pr1 axis as master regulator of efficient thrombopoiesis and might raise new therapeutic options for patients with thrombocytopenia

Treatment with the immunomodulator FTY720 does not promote spontaneous bacterial infections after experimental stroke in mice

Background: FTY720, an immunomodulator derived from a fungal metabolite which reduces circulating lymphocyte counts by increasing the homing of lymphocytes to the lymph nodes has recently gained interest in stroke research. The aim of this study was to evaluate the protective efficacy of FTY720 in cerebral ischemia in two different application paradigms and to gather first data on the effect of FTY720 on the rate of spontaneous bacterial infections in experimental stroke. Methods: Middle cerebral artery occlusion (MCAO) in C57BL/6 mice (strain J, groups of 10 animals) was performed with two different durations of ischemia (90 min and 3 h) and FTY720 was applied 2 h after vessel occlusion to study the impact of reperfusion on the protective potency of FTY720. Lesion size was determined by TTC staining. Mice treated with FTY720 or vehicle were sacrificed 48 h after 90 min MCAO to determine the bacterial burden in lung and blood. Results: FTY720 1 mg/kg significantly reduced ischemic lesion size when administered 2 h after the onset of MCAO for 3 h (45.4 +/- 22.7 mm3 vs. 84.7 +/- 23.6 mm3 in control mice, p = 0.001) and also when administered after reperfusion, 2 h after the onset of MCAO for 90 min (31.1 +/- 28.49 mm3 vs. 69.6 +/- 27.2 mm3 in control mice, p = 0.013). Bacterial burden of lung homogenates 48 h after stroke did not increase in the group treated with the immunomodulator FTY720 while there was no spontaneous bacteremia 48 h after MCAO in treated and untreated animals. Conclusions: Our results corroborate the experimental evidence of the protective effect of FTY720 seen in different rodent stroke models. Interestingly, we found no increase in bacterial lung infections even though FTY720 strongly reduces the number of circulating leukocytes

Müntz-Memorial oder Unbetrüglicher Vorschlag Von dem rechten Principal- und Haupt-Stück : Dadurch dem heutigen Müntz-Unwesen und denen dran hangenden vielen grossen Greueln eiligst zu remediren/ Und hingegen alles ... leicht und förderlichst in einen guten Stand wieder zu bringen ; Aus unterschiedlichen hierüber eingeholeten Academischen Consiliis, wie auch andern ... Rechten/ Käyserl. Reichs-Abscheiden/ Chur- und Fürstl. Müntz-Edicten, wolgegründeten/ curieuxen raren Schrifften wolmeinend zusammen getragen Und Zu unzweifflicher Redreßirung aller ... ruinirten Stände in gantz Teutschland fürgestellet

von Christiano Billic

Cellular assay for the characterization of sphingosine-1-phosphate lyase inhibitors

Sphingosine-1-phosphate (S1P) lyase represents a target for therapeutic intervention in immune regulation. Inhibitors of the lyase can be identified by established biochemical assays, but a cellular test system for such inhibitors has not been described so far. We found that silencing or inhibition of S1P lyase with siRNA or active-site directed inhibitors in cultured mammalian cells does not cause a relevant increase of S1P in the cells as measured by LC-MS/MS. However, addition of sphingosine to cultures of cell lines or primary cells provides a source of intracellular S1P that is susceptible to degradation by the lyase and hence increases upon inhibition or silencing of the enzyme. The assay was optimized with respect to sphingosine concentration, incubation time, and cell density, and was routinely established for use with HEK293 cells. The assay was found suitable for the testing of novel active-site directed S1P lyase inhibitors, providing important information on their relative potency in intact cells

Assay to measure the secretion of S1P from cells induced by S1P lyase inhibitors

Inhibitors of the sphingosine-1-phosphate (S1P) degrading enzyme S1P lyase (SPL) may be useful in the therapy of inflammatory diseases by preventing lymphocyte recruitment to diseased tissues. Here we describe a cellular assay for such inhibitors, which takes advantage of the observation that a fraction of the intracellular S1P accumulated in the presence of SPL inhibitors is secreted into the medium of cultured cells. The secreted S1P is then quantified using an S1P-sensitive reporter cell line. In the routine assay protocol, human HEK293T cells are treated with SPL inhibitors in the presence of phosphatase inhibitors and sphingosine; while the phosphatase inhibitors are included to prevent the degradation of S1P secreted from the cells, sphingosine is added as source for intracellular S1P that is prone to SPL degradation. The secreted S1P in the supernatant of the cell cultures is then quantified by measuring calcium flux induced in CHO-K1 cells expressing the human S1P3 receptor. Using this method SPL inhibitors were shown to induce a concentration-dependent increase of extracellular S1P under the conditions used; thus, the assay allows for the ranking of SPL inhibitors according to their potency on living cells

BZM055, a SPECT tracer candidate for studying FTY720 brain distribution and myelin imaging

FTY720 (fingolimod, Gilenya®) is a sphingosine 1-phosphate (S1P) receptor modulator that showed significant therapeutic efficacy after oral administration to multiple sclerosis patients. We propose here an imaging tracer to study the pharmacokinetics and organ distribution of FTY720 in patients and, since this drug accumulates in myelin sheaths, for myelin imaging. FTY720 does not contain any atom whose PET or SPECT radioisotope would have a half-life compatible with its pharmacokinetic properties. We hence searched for a radiolabeled derivative that would be an adequate surrogate of the drug, mimicking its pharmacokinetics and organ distribution, but also its affinity, selectivity for S1P receptors, phosphorylation kinetics, and overall physicochemical properties. We selected a close mimic of the drug, BZM055 (2a), for radiolabeling and further characterizatio