The KND olygopeptide as a putative endogenous prototype of Delta Sleep Inducing Peptide (DSIP). comparative study of biological properties

Biological properties of the known Delta Sleep-Inducing Peptide (DSIP, WAGGDASGE) were studied in vivo in comparison with those of a new DSIP-homologous peptide (WKGGNASGE — ([K ², N ⁵]DSIP, KND). This new peptide was recently discovered as the 324–332 fragment of the human lysine-specific histone demethylase 3B (EC 1.14.11, Swiss-Prot: Q7LBC6.1, 1761 a.a.) in the course of a computer search in available databases of proteins and nucleic acids. This demethylase belongs to the JmjC-domain-containing family of histone demethylases which are encoded by the JMJD1B gene and present in tissues of various mammals. These studies confirmed our preliminary conclusions on the functional similarity between the biological activities of DSIP and KND. The examined antioxidative, anticonvulsive, and behavioral effects of KND proved to be more pronounced than those of DSIP. The obtained results additionally sup-ported our hypothesis about KND being an endogenous prototype of a “real” DSIP.     

Insights into Distinct Modulation of α7 and α7β2 Nicotinic Acetylcholine Receptors by the Volatile Anesthetic Isoflurane

Nicotinic acetylcholine receptors (nAChRs) are targets of general anesthetics, but functional sensitivity to anesthetic inhibition varies dramatically among different subtypes of nAChRs. Potential causes underlying different functional responses to anesthetics remain elusive. Here we show that in contrast to the α7 nAChR, the α7β2 nAChR is highly susceptible to inhibition by the volatile anesthetic isoflurane in electrophysiology measurements. Isoflurane-binding sites in β2 and α7 were found at the extracellular and intracellular end of their respective transmembrane domains using NMR. Functional relevance of the identified β2 site was validated via point mutations and subsequent functional measurements. Consistent with their functional responses to isoflurane, β2 but not α7 showed pronounced dynamics changes, particularly for the channel gate residue Leu-249(9′). These results suggest that anesthetic binding alone is not sufficient to generate functional impact; only those sites that can modulate channel dynamics upon anesthetic binding will produce functional effects.     

Effect of weight loss and exercise on angiogenic factors in the circulation and in adipose tissue in obese subjects

Background:

Vascular growth is a prerequisite for adipose tissue (AT) development and expansion. Some AT cytokines and hormones have effects on vascular development, like vascular endothelial growth factor (VEGF‐A), angiopoietin (ANG‐1), ANG‐2 and angiopoietin‐like protein‐4 (ANGPTL‐4).

Methods:

In this study, the independent and combined effects of diet‐induced weight loss and exercise on AT gene expression and proteins levels of those angiogenic factors were investigated. Seventy‐nine obese males and females were randomized to: 1. Exercise‐only (EXO; 12‐weeks exercise without diet‐restriction), 2. Hypocaloric diet (DIO; 8‐weeks very low energy diet (VLED) + 4‐weeks weight maintenance diet) and 3. Hypocaloric diet and exercise (DEX; 8‐weeks VLED + 4‐weeks weight maintenance diet combined with exercise throughout the 12 weeks). Blood samples and fat biopsies were taken before and after the intervention.

Results:

Weight loss was 3.5 kg in the EXO group and 12.3 kg in the DIO and DEX groups. VEGF‐A protein was non‐significantly reduced in the weight loss groups. ANG‐1 protein levels were significantly reduced 22‐25% after all three interventions (P < 0.01). The ANG‐1/ANG‐2 ratio was also decreased in all three groups (P < 0.05) by 27‐38%. ANGPTL‐4 was increased in the EXO group (15%, P < 0.05) and 9% (P < 0.05) in the DIO group. VEGF‐A, ANG‐1, and ANGPTL‐4 were all expressed in human AT, but only ANGPTL‐4 was influenced by the interventions.

Conclusions:

Our data show that serum VEGF‐A, ANG‐1, ANG‐2, and ANGPTL‐4 levels are influenced by weight changes, indicating the involvement of these factors in the obese state. Moreover, it was found that weight loss generally was associated with a reduced angiogenic activity in the circulation.     

Proteasome Expression in Ovarian Heterotopic Allografts of Wistar and August Rats under Induction of Donor-Specific Tolerance

Russian Journal of Developmental Biology - The aim of this work is to investigate the dynamics for the ovarian tissue engraftment of inbred August rats transplanted to outbred Wistar rats and vice...     

Cellular laminin-binding protein and Venezuelan equine encephalomyelitis virus replication in Vero, 293 and 9S2 cells

The expression of the laminin-binding protein (LBP) on cellular membranes in different cell lines has been studied. A high level of replication of Venezuelan equine encephalomyelitis (VEE) virus was registered in Vero cells with high levels of LBP on the cell surface. The treatment of Vero cells with monoclonal antibodies to human LBP reduced VEE virus replication by a factor of more than 200. A low level of LBP expression on the surface of 293 cells was increased via transfection by plasmid with gene for human LBP. The VEE virus replication in transfected cells (9S2) was increased by more that 2000 times compared to the 293 cells. The results demonstrated the principal role of cellular LBP in the entry of VEE virus into mammalian cells. It is proposed that LBP is a key cellular protein for the early stage of the VEE virus replication in cells. LBP may be a target protein for the development of a new generation of antiviral drugs capable of inhibiting (enhancing) the alphavirus replication in human cells.     

Mass spectral study of polymorphism of the apolipoproteins of very low density lipoprotein

New isoforms of apolipoprotein (apo)C-I and apoC-III have been detected in delipidated fractions from very low density lipoprotein (VLDL) using matrix-assisted laser desorption (MALDI) and electrospray ionization (ESI) mass spectrometry (MS). The cleavage sites of truncated apoC-III isoforms have also been identified. The VLDL fractions were isolated by fixed-angle single-spin ultracentrifugation using a self-generating sucrose density gradient and delipidated using a newly developed C18 solid phase extraction protocol. Fifteen apoC isoforms and apoE were identified in the MALDI spectra and the existence of the more abundant species was verified by ESI-MS. The relative intensities of the apoCs are closely correlated in three normolipidemic subjects. A fourth subject with type V hyperlipidemia exhibited an elevated apoC-III level and a suppressed level of the newly discovered truncated apoC-I isoform. ApoC-II was found to be particularly sensitive to in vitro oxidation. The dynamic range and specificity of the MALDI assay shows that the complete apoC isoform profile and apoE phenotype can be obtained in a single measurement from the delipidated VLDL fraction.     

Free radical oxidation and antiradical protection of the rat brain during adaptation to intense physical loading

The cerebral free radical oxidation processes on 40 Wistar rats-males were studied by evaluation of thiobarbituric-active products of lipid peroxidation level, superoxide dismutase and glutathione peroxidase activity in sensomotor cortex, hypothalamus and brain stem. Was found that differential stability of rats to motor activities during single intensive physical loading is due by reactivity of free radicals oxidation, associated with decrease of cerebral antioxidant enzymes activity. Long term intensive physical loading may accompanied by reducing of reserve possibilities of antioxidant enzymes an cerebral structures, what possible play potential role in pathogenetic mechanisms of osteoarthritis.     

Free radical mechanism of the cold stress development in rats

Development of cold stress in rats is characterized by sharp activation of lipid peroxidation accompanied by a considerable increase of the diene conjugates level and Schiff bases in tissues of brain, liver and in erythrocytes. There is a shift in the prooxidant--antioxidant balance of the organism in the form of amplification of xanthine oxidase prooxidant enzymatic activity in the brain and liver, and a decrease of myeloperoxidase activity in blood neutrophiles of rats. The attrition at cold stress, mainly, of enzymatic endocellular antioxidant system as the result of inhibition of superoxide dismutase, catalase, glutathione reductase activities in brain, liver and erythrocytes is indemnified by activation of non-enzymatic antioxidant mechanisms. In conditions of cold stress, destabilization of erythrocyte membranes of rats described by a decrease of the microviscosity of protein-lipid contact zones and reduction of degree of immersing of proteins in lipid membrane owing to exhibiting proteins from the hydrophobic zone of membranes, or their aggregate, increase of polarity of lipid phase and negative surface charge, is marked.