One session of exercise regulates cathepsin B activity in the livers of trained and untrained rats.

Physical exercise causes adaptive changes, mainly in muscles, but it also influences other organs, including liver. Most changes are beneficial; however, strenuous exercise is a strong stressor, and it can result in splanchnic hypoperfusion with subsequent disturbances in liver homeostasis and energy. Cathepsin B is a protease linked to protein turnover and extracellular matrix degradation. It is also involved in autophagy and the activation of proinflammatory and profibrotic pathways. This study investigated the influences of one session of exercise and endurance training on the mRNA, protein level, and activity of cathepsin B in rat liver. Healthy rats were randomly divided into two groups (n = 30, each); one group was untrained and the other received 6-weeks of endurance training with an increasing load. For each group, rats were sacrificed before (controls, n = 10), immediately after (n = 10), and 3 h after (n = 10) an acute bout of intense exercise. Liver gene expression was evaluated with quantitative real-time PCR. Liver protein content was measured with ELISA. Liver enzyme activity was measured fluorometrically. One session of exercise or training did not influence cathepsin B gene expression or protein concentration at any investigated time point. In untrained rats, cathepsin B activity decreased 3 hours after (P = 0.027) one session of exercise. In trained rats, cathepsin B activity increased immediately (P = 0.005) after one session of exercise. Training did not influence baseline cathepsin B activity. In conclusion, one session of exercise differentially influenced cathepsin B activity in the liver, depending on training status.

Comparison of Two Methods for Determination of NGAL Levels in Urine: ELISA and CMIA.

BACKGROUND: Neutrophil gelatinase-associated lipocalin (NGAL) is a new useful biomarker for the early diagnosis of acute kidney injury. The aim of the study was to compare two analytical methods for measurement of urinary NGAL: enzyme-linked immunosorbent assay (ELISA) and chemiluminescent microparticle immunoassay (CMIA). METHODS: Two assays were used to measure urinary NGAL: ELISA kit (R&D Systems) and ARCHITECT Urine NGAL (Abbott Laboratories). The study material was the urine obtained from 30 healthy subjects (mean age 56.4 ± 15.2). RESULTS: The median value and interquantile range of urinary NGAL in the studied group measured by ELISA (R&D Systems) were 3.5 ng/ml (1.2; 6.6) and by CMIA (ARCHITECT Urine NGAL assay, Abbott Diagnostics) were 4.4 ng/ml (1.9; 9.4). Levels of urinary NGAL obtained by CMIA were significantly higher than by ELISA. There was a significant positive correlation between the concentration of urinary NGAL determined by both methods (r = 0.8625, P < 0.01). CONCLUSION: The comparison of individual data obtained by ELISA and CMIA should be taken with care. From laboratory's point of view, ELISA is less expensive than CMIA method for the determination of NGAL in urine. However, CMIA method allows rapid determination of urinary NGAL concentration through automated assay.

Strong association between fibronectin accumulation and lowered cathepsin B activity in glomeruli of diabetic rats.

In diabetic nephropathy the progressive accumulation of extracellular matrix (ECM) proteins results from an imbalance between synthetic and degradative pathways. While the role of the different matrix metalloproteinases in the impaired ECM degradation has been studied in detail, the function of lysosomal cysteine proteinases has not received adequate attention. The aim was to investigate a potential relationship between the accumulated ECM protein fibronectin (FN), and cathepsin B activity in isolated glomeruli of diabetic and healthy rats. Twenty male Wistar rats were included: 10 healthy and 10 with streptozotocin-induced diabetes. After 6 weeks, the experiments were terminated. In the homogenates of isolated glomeruli, FN content and cathepsin B activity were measured by ELISA or spectrofluorometry. FN was also analyzed by immunohistochemistry. Diabetic rats showed a significant rise of systolic blood pressure, impaired renal function and an enhanced urinary excretion of albumin, FN and cathepsin B. In the homogenates of the isolated glomeruli the ratios of FN/protein and FN/DNA showed a trend to higher values, while the ratios of cathepsin B/protein and cathepin B/DNA were reduced. The strong positive association between intraglomerular FN content and cathepsin B activity of in both groups suggests that this cysteine proteinase contributes to the degradation of the ECM protein FN. The much higher FN content in DN rats associated with an inadequate cathepsin B activity implies the role of an insufficient FN degradation by cathepsin B and other proteinases.

Inflammatory cytokines gene expression in bone tissue from patients with chronic rhinosinusitis- a preliminary study.

BACKGROUND: It is unclear whether mucosal inflammation has an effect on the bone under the mucosa in patients with chronic rhinosinusitis (CRS). OBJECTIVES: The aim of this study was evaluation of inflammatory cytokines genes expression in bone tissue taken from the patients who had undergone endoscopic sinus surgery for CRS. METHODS: A total group of a consecutive 49 patients with diagnosis of chronic rhinosinusitis based on EPOS 2007 criteria undergoing endoscopic sinus surgery for CRS were enrolled in the study. Based on histopathologic findings of the mucosal and bone tissues we evaluated the rate of inflammation. Expression of target genes: interleukin 1ß (IL1ß), interleukin 6 (IL6), interleukin 11 (IL11), tumor growth factor ß (TGF ß) and tumor necrosis factor α (TNF α) were analysed by real-time PCR method in samples of the ethmoid bone taken during endoscopic sinus surgery for CRS. RESULTS: Based on histopathological findings in the studied population we found symptoms of osteitis in 5 patients. In the studied population we found significant differences between patients with osteitis and without osteitis with respect to IL6 gene expression in bone tissue (p=0.0003), IL11 gene expression (p=0.02) and TNFα gene expression in bone tissue (p=0.0035). CONCLUSION: In our study we have demonstrated that in some patients with CRS and coexisting symptoms of osteitis some inflammatory markers genes expression are increased in this population.