Intranasal administration of the peptide Selank regulates BDNF expression in the rat hippocampus in vivo

Selank, Peptide Analogue of Tuftsin, Protects Against Ethanol-Induced Memory Impairment by Regulating of BDNF Content in the Hippocampus and Prefrontal Cortex in Rats

The effects of a peptide anxiolytic Selank synthesized on the basis of the endogenous peptide tuftsin on memory impairment and content of brain-derived neurotrophic factor (BDNF) in brain structures were analyzed in outbred rats receiving 10% ethanol as the only source of fluid for 30 weeks. In the object recognition test, Selank (0.3 mg/kg a day, 7 days, intraperitoneally) produced a cognitive-stimulating effect in 9 months rats not exposed to ethanol (p<0.05) and prevented the formation of ethanol-induced memory and attention disturbances (p<0.01) developing during alcohol withdrawal. In ex vivo experiments, Selank prevented ethanol-induced increase in BDNF content in the hippocampus and frontal cortex (p<0.05). These results indicate positive effects of the tuftsin analogue on age-related memory disturbances associated with chronic alcohol intoxication and confirm the involvement of the neurotrophin mechanism related to BDNF production into the effect of Selank.

GABA, Selank, and Olanzapine Affect the Expression of Genes Involved in GABAergic Neurotransmission in IMR-32 Cells

Clinical studies have shown that Selank had an anxiolytic effect comparable to that of classical benzodiazepine drugs, which can enhance the inhibitory effect of GABA by allosteric modulation of GABA_A receptors. These data suggest that the molecular mechanism of the effect of Selank may also be related to its ability to affect the performance of the GABAergic system. To test this hypothesis, we studied the changes in expression of 84 genes involved in the functioning of the GABAergic system and in the processes of neurotransmission in the culture of neuroblastoma IMR-32 cells using qPCR method. As test substances, in addition to Selank, we selected the major GABA_A receptor ligand, GABA, the atypical antipsychotic, olanzapine, and combinations of these compounds (Selank and GABA; Selank and olanzapine). We found no changes in the mRNA levels of the genes studied under the effect of Selank. The combined effect of GABA and Selank led to nearly complete suppression of changes in expression of genes in which mRNA levels changed under the effect of GABA. When Selank was used in conjunction with olanzapine, the expression alterations of more genes were observed compared with olanzapine alone. The data obtained indicate that Selank has no direct effect on the mRNA levels of the GABAergic system genes in neuroblastoma IMR-32 cells. At the same time, our results partially confirm the hypothesis that the peptide may affect the interaction of GABA with GABA_A receptors. Our data also suggest that Selank may enhance the effect of olanzapine on the expression of the genes studied.

[Optimization of the treatment of anxiety disorders with selank]

AIM

To compare the efficacy and tolerability of monotherapy with phenazepam to complex treatment with the peptide preparation selank and phenazepam in patients with anxiety disorders.

MATERIAL AND METHODS

Authors explored the anxiolytic effect and tolerability of monotherapy with phenazepam (30 patients) and complex treatment with selank and phenazepam (40 patients) in anxiety-phobic, hypochondriac and somatoform disorders (ICD-10 items F40.2-9, F41.1-9, F45.0-2). Therapeutic effect was assessed clinically and with HDRS, CGI and Spilberger scales. Tolerability was evaluated using the UKU scale. Stroop test and verbal fluency test were used. Quality of life was assessed with the SF-36.

RESULTS

The positive effect of phenazepam was achieved earlier in the optimization of treatment with selank on HDRS. The combined treatment decreased the level of undesirable side-effects of phenazepam (attention and memory impairment, asthenia, sedation, increase in sleep duration, sexual disturbances, emotional indifference and orthostatism) during the course of treatment and after the tranquilizer withdrawal. Taken together, the therapeutic efficacy and reduction of side-effects had a positive impact on the quality-of-life of the patients treated with selank as add-on to phenazepam.

CONCLUSION

The results extend therapeutic possibilities of treatment of anxietyspectrum disorders with the combination of benzodiazepine tranquilizers and selank.