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Humanin (HN) and humanin-like substances are short polypeptides that prevent neuronal cell death and dysfunction related to progression of Alzheimer's disease. HN activates oligomeric receptor (CNFTR/WSX-1/gp130 complex) in the extracellular environment, and it is believed to interact with intracellular proteins, such as Bcl2 family. HN stimulates JAK2/STAT3 pathway that regulates apoptosis and cell death, however exact molecular mechanism of HN mediated cytoprotection remains unknown.The goal of our study was to evaluate effect HN (HNM) and HN-like peptides, which include HNG, HN10d and HN 10dV, on the intracellular calcium release in the cultured brain cells (LN18, C8D1A) and endothelial HUVECs under stress conditions.We incubated the cells with low amounts of HN (4 µM) for 24 hours, generated cellular stress by addition of either 25 µM β-amyloid (neuronal and glial cells) or 5 ng/mL of TNF-α (endothelial cells); and induced calcium release with 10 µM ATP.

The fibrin clot permeability coefficient (Ks) is a useful measure of porosity of the fibrin network, which is determined by a number of genetic and environmental factors. Currently available methods to evaluate Ks are time-consuming, require constant supervision and provide only one parameter. We present an automated method in which drops are weighed individually, buffer is dosed by the pump and well defined clot washing is controlled by the software. The presence of a straight association between drop mass and their dripping time allows to shorten the measurement time twice. In 40 healthy individuals, Ks, the number of drops required to reach the plateau (DTP), the time to achieve the plateau (TTP) and the DTP/TTP ratio (DTR) were calculated. There was a positive association between Ks (r = 0.69, P < 0.0001) evaluated by using the manual [median of 4.17 (3.60-5.18) ·10⁻⁹ cm²) and the automated method [median of 4.35 (3.74-5.38) ·10⁻⁹ cm²]. The correlation was stronger (r = 0.85, P < 0.001) in clots with DTP of 7 or less (n = 12). DTP was associated with total homocysteine (tHcy) (r = 0.35, P < 0.05) and activated partial thromboplastin time (APTT) (r = -0.34, P < 0.05), TTP with Ks (r = -0.55, P < 0.01 for the manual method and r = -0.44, P < 0.01 for the automated method) and DTP (r = 0.75, P < 0.0001), and DTR with Ks (r = 0.70, P < 0.0001 for the manual method and r = 0.76, P < 0.0001 for the automated method), fibrinogen (r = -0.58, P < 0.0001) and C-reactive protein (CRP) (r = -0.47, P < 0.01). The automated method might be a suitable tool for research and clinical use and may offer more additional parameters describing fibrin clot structure.