Due to its nootropic, neuroprotective, and immunomodulatory effects, the peptide Semax is utilized in the treatment of ischemic stroke. Our earlier RNA-Seq analysis of the transcriptome in an ...ischemic model of transient occlusion of the middle cerebral artery showed an increase in the mRNA levels of many proinflammatory genes, and the suppression of their induction by Semax. However, for many relevant genes, including
Il1a
,
Il1b
,
Il6
and
Tnfa
, the levels of their expression were too low for detailed quantitative evaluation. Here we utilize qRT-PCR to analyze the effects of the Semax peptide on the expression of weakly expressed mRNAs encoding several proinflammatory mediators, and show that exposure to Semax leads to a statistically significant decrease in the
Il1a
,
Il1b
,
Il6
,
Ccl3
, and
Cxcl2
mRNAs, which compensates for the increase in the transcription of these genes induced by ischemia-reperfusion. We conclude that the observed protective effect of Semax in the model of stroke may be due to its anti-inflammatory effects. We also discuss the limitations of the RNA-Seq when applied to quantifying less abundant transcripts as compared to the real-time RT-PCR method.
The reaction between spillover hydrogen (SH) and mexidol upon high-temperature solid state catalytic isotope exchange (HSCIE) is studied experimentally and via DFT B3LYP and MP2 calculations. ...The distribution of isotopes and the activation energy of the reaction are determined via NMR spectro-scopy and mass spectrometry for samples of the deuterium-labeled mexidol obtained via HSCIE at 50–120°C. The DFT calculated activation energy of hydrogen transfer on the charged alumina cluster HH
+
(‒Al–O–)
3
(OH)
6
is found to agree with the experimental data. A mechanism is proposed for HSCIE between the adsorbed compound and charged Brønsted acid sites formed on the surface of the support upon exposure to hydrogen spillover.
We studied the effect of chronic intranasal and peroral administration of a new peptide preparation AСTH
15-18
PGP in a dose of 100 mg/kg body weight on the state of vascular-platelet and plasma ...hemostasis in animals. It was found that this synthetic regulatory peptide administered intranasally can produce antiplatelet, anticoagulant, and antifibrin-stabilizing effects on the blood plasma in healthy rats. In both administration routes, the peptide induced activation of the anticoagulation system of the hemostasis by increasing enzymatic and non-enzymatic fibrinolysis; after intranasal administration, the fibrinolytic effects were more pronounced.
The synthesis of Boc-Gly-Pro-Dox, Boc-Gly-Pro-DOPA, and Boc-Gly-Pro-Srt and their deuterated analogues was carried out. The condensation is accompanied by side reactions, which could be minimized by ...optimizing the reaction conditions. The most versatile approach to the synthesis of Boc-Gly-Pro-Dox, Boc-Gly-Pro-DOPA, and Boc-Gly-Pro-Srt and their deuterated analogues is condensation of Boc-Gly-Pro or Boc-Gly-
2
HPro with the amino groups of dopamine, serotonin, and doxorubicin. For the introduction of hydrogen isotopes into ΔPro, hydrogenation of its aqueous solution followed by condensation of the reduced proline with Boc-GlyOSu is recommended. Mass spectrometry was used to determine the content of isotopomers in the deuterated products.
Melanocortins form a class of regulatory peptide currently under active study; these include such biologically active substances as adrenocorticotropic hormone (ACTH) and α- β-, and ...γ-melanocyte-stimulating hormone (MSH). ACTH fragments, like other peptides of the melanocortins family, have marked neurotropic effects, particularly stimulating learning, memory, and attention processes. The active center of ACTH required for activation of all types of melanocortin receptor, is the sequence His-Phe-Arg-Trp and corresponds to fragment ACTH
6–9
. We report here studies of the synthetic peptide ACTH
6–9
-PGP, whose structure contains the natural fragment ACTH
6–9
stabilized at the C terminal by attachment of the amino acid sequence prolyl-glycyl-proline (PGP) to increase resistance to the actions of carboxypeptidases. The effects of i.p. administration of ACTH
6–9
-PGP at doses of 0.5, 5, 50, 150, and 450 μg/kg as single does 15 min before assessment of anxiety levels in rats in the Vogel confl ict situation test (punished behavior) and the elevated plus maze (unpunished behavior) were studied. The effects of ACTH
6–9
-PGP in these tests were compared with those of its structural analog ACTH
4–7
-PGP at doses of 50, 150, and 450 μg/kg. The results showed that ACTH
6–9
-PGP in the Vogel conflict situation test increased anxiety levels in rats, which was apparent as decreases in drinking time (at all doses) and reductions in the number of licks (at doses of 0.5 and 150 μg/kg) (
p
< 0.01). ACTH
6–9
-PGP had no significant effect on the rats’ behavior in the elevated plus maze. ACTH
4–7
-PGP had no effects in the models of punished and unpunished behavior. Thus, ACTH
6–9
-PGP, in contract to ACTH
4–7
-PGP, was found to affect anxiety levels in rats, depending on the dose of peptide and the behavioral model used.
—
Intranasal administration of lysine- and arginine-containing peptides Lys-Lys-Arg-Arg-Pro-Gly-Pro and Lys-Arg-Arg-Lys-Pro-Gly-Pro was performed daily at a single dose of 100 µg/kg for 7 days on ...laboratory rats with experimental metabolic syndrome and endothelial dysfunction. Metabolic syndrome was modeled by a high-calorie diet maintained throughout the experimental period, while endothelial dysfunction was simulated by daily intraperitoneal injection of L–NAME at a single dose of 10 mg/kg for 5 days. It was found that these peptides had anticlotting, hypoglycemic, and lipid-lowering effects and reduced body weight gain in experimental rats. They affected both primary (vascular-platelet) hemostasis, decreasing platelet aggregation, and all elements of plasma hemostasis by increasing anticoagulant, fibrin-depolymerizing, and enzymatic fibrinolytic activities as well as anti-fibrin-stabilizing properties of plasma and reducing the concentration of fibrinogen in it. At the same time, the studied peptides diminished the content of total cholesterol, low-density lipoprotein cholesterol, and triglycerides, while increasing the concentration of high-density lipoprotein cholesterol. These effects were observed 20 h after the last administration of peptides and persisted, although to a lesser extent, 7 days (168 h) after treatment withdrawal. In this regard, the prolonged action can be considered for both glyproline peptides containing lysine and arginine aminoacid residues in their structure and their ability to protect the body from the development of metabolic diseases and endothelial dysfunction. The maximum effects were provided by the Lys-Arg-Arg-Lys-Pro-Gly-Pro peptide, which may be associated with its structural features.
Necessary precursors for obtaining tritium-labeled Z-Gly-Pro-DOPA, Z-Gly-Pro-SRT, Z-Gly-Pro-Dox, OL-Gly-Pro-DOPA,Ol-Gly-Pro-Srt were synthesized for the first time (Gly stands for glycine; Pro, ...proline; Ol, Oleic acid, DOPA, dopamine; Dox, Doxorubicin; Srt, Serotonin; and Z, benzyloxycarbonyl protection). The tritium-labeled proline and glycine were used to synthesize peptide derivatives of DOPA, Dox, and Srt with different tritium distributions.
Boc-Pro-Dox, Boc-Pro-DOPA, Boc-Pro-Srt, and Pro-Dox, Pro-DOPA, Pro-Srt, as well as Boc-
2
НPro-Dox, Boc-
2
НPro-DOPA, Boc-
2
НPro-Srt, and
2
НPro-Dox,
2
НPro-DOPA,
2
НPro-Srt have been synthesized ...for the first time. Boc-
2
НPro is the most promising reagent for the preparation of deuterated compounds. The hydrogenation of Boc-ΔPro in ethyl acetate on palladium catalyst has allowed the introduction of deuterium by a factor of 1.6–1.65 larger than by the hydrogenation of unsaturated proline bound to serotonin and by a factor of three larger than by the hydrogenation of unsaturated proline bound to dopamine. Due to doxorubicin instability under conditions of unsaturated proline hydrogenation, its condensation with Boc-
2
НPro is the sole possibility to prepare Boc-
2
НPro-Dox. The content of isotopomers in the deuterated products has been determined by mass spectrometry.
Racemic phosphinic tripeptide
1
pyrrolidin-2-yl-{3-(2-hydroxycarbonyl)-pyrrolidin-1-yl-3-oxo-propyl}-phosphinic acid has been synthesized, its high resistance toward leucine aminopeptidase, ...carboxypeptidase Y, and the enzyme system of rat brain membranes has been shown. In vitro experiments with using Semax synthetic peptide have shown that the effect of tripeptide
1
on the hydrolysis rate of Semax in the case of leucine aminopeptidase and carboxypeptidase Y is minimal. In experiments using the enzyme system of rat brain membranes, the decrease of the rate of Semax hydrolysis has been more evident.
Precursors were synthesized for the first time for obtaining tritium-labeled Вос-Gly-Pro-DOPA, Вос-Gly-Pro-Srt, LА-Gly-Pro-DOPA, LА-Gly-Pro-Srt, Вос-Pro-DOPA, Вос-Pro-Srt, Вос-Gly-Pro-Dox, ...LА-Gly-Pro-Dox, Вос-Pro-Dox. Tritium is introduced by using dehydroproline derivatives N-protected by a
tert
-butyloxycarbonyl group or lauric acid. The suggested approach made it possible to obtain labeled compounds in high yield with high molar radioactivity. A new procedure is suggested for purification of water-insoluble compounds by solid-phase extraction.
