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Molecular Mechanism Underlying the Action of Substituted Pro-Gly Dipeptide Noopept.

Vakhitova YV, Sadovnikov SV, Borisevich SS, Ostrovskaya RU, A Gudasheva T, Seredenin SB - Acta Naturae (2016 Jan-Mar)

Bottom Line: Piracetam (1 mM) failed to affect significantly any of the TF under study.The results of molecular docking showed that Noopept (L-isomer), as well as its metabolite, L-isomer of N-phenyl-acetylprolyl, unlike its pharmacologically ineffective D-isomer, is able to bind to the active site of prolyl hydroxylase 2.The obtained data allow one to propose the HIF-positive effect as the primary mechanism of the activity of this Pro-Gly-containing dipeptide.

View Article: PubMed Central - PubMed

Affiliation: State Zakusov Institute of Pharmacology , Baltiyskaya Str., 8, 125315, Moscow, Russia ; Institute of Biochemistry and Genetics of Ufa Scientific Centre RAS, Prospekt Oktyabrya, 71, 450065 , Ufa, Russia.

ABSTRACT
This study was performed in order to reveal the effect of Noopept (ethyl ester of N-phenylacetyl-Lprolylglycine, GVS-111) on the DNA-binding activity of transcriptional factors (TF) in HEK293 cells transiently transfected with luciferase reporter constructs containing sequences for CREB, NFAT, NF-κB, p53, STAT1, GAS, VDR, HSF1, and HIF-1. Noopept (10 μM) was shown to increase the DNA-binding activity of HIF-1 only, while lacking the ability to affect that of CREB, NFAT, NF-κB, p53, STAT1, GAS, VDR, and HSF1. Noopept provoked an additional increase in the DNA-binding activity of HIF-1 when applied in conditions of CoCl2-induced HIF- 1 stabilization. The degree of this HIF-positive effect of Noopept was shown to be concentration-dependent. Piracetam (1 mM) failed to affect significantly any of the TF under study. The results of molecular docking showed that Noopept (L-isomer), as well as its metabolite, L-isomer of N-phenyl-acetylprolyl, unlike its pharmacologically ineffective D-isomer, is able to bind to the active site of prolyl hydroxylase 2. Taking into account the important role of the genes activated by HIF-1 in the formation of an adaptive response to hypoxia, data on the ability of Noopept to provoke a selective increase in the DNA-binding activity of HIF-1 explain the wide spectrum of neurochemical and pharmacological effects of Noopept revealed before. The obtained data allow one to propose the HIF-positive effect as the primary mechanism of the activity of this Pro-Gly-containing dipeptide.

No MeSH data available.


Related in: MedlinePlus

Hypoxia-induced factor HIF-1 and its targets. Modified according to [24]
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Figure 4: Hypoxia-induced factor HIF-1 and its targets. Modified according to [24]

Mentions: The factor induced by hypoxia (HIF-1) is a heterodimer composed of twosubunits: a HIF-1α subunit sensitive to oxygen and constitutivelyexpressed HIF-1β. Hypoxia promotes an increase in the HIF-1α level,its dimeriation with HIF-1β, mobilization of coactivators (p300/CBP), andbinding of this complex to HRE (hypoxia-response element) in the regulatoryregions of target genes. In normoxic conditions, oxygen-dependent hydroxylationof proline residues in the HIF- 1α molecule by prolyl hydroxylases isnecessary for binding by the component of ubiquitin-protein ligase E3, vonHippel-Lindau (VHL) protein. Ubiquitinated HIF-1α becomes a target fordegradation by 26S proteasomes. The asparagine residue at the C-terminaltransactivation domain (C-TAD) of HIF-1α is hydroxylated by asparaginhydroxylase (FIH1, factor inhibiting HIF-1) in the presence of oxygen, therebyblocking its interaction with the transcriptional coactivator p300/CBP. Thus,PHD and FIH inactivate HIF-1α in normoxia, suppressing HIF-1-dependentexpression of the target genes. PHD and FIH activity decreases under conditionsof hypoxia, leading to a decrease in HIF-1α degradation andtranscriptional activation of its dependent genes[24]. It has been shown[25] that HIF-1 activates a total of up to 100genes. Figure 4 presentsthe main targets of HIF-1, which includethe genes involved in angiogenesis through activation of the vascular endothelialgrowth factor, enhanced synthesis of erythropoietin, activation of the systemsof glucose transport through membranes, cytoprotection by neurotrophic factors,normalization of cell cycle and metabolism at the mitochondrial level, as wellas the activity of antioxidant enzymes: superoxide dismutase and catalase. Thecombination of these effects allows the implementation of an adaptive responseto hypoxic exposure. Alongside with this, HIF-1 affects the state of manyneurotransmitter systems: it activates the protein responsible for control ofGABA receptors (GABARBP) [26] andincreases tyrosine hydroxylase activity [27].The close relation between HIF-1 and cholinergicreceptors has been described [28].


Molecular Mechanism Underlying the Action of Substituted Pro-Gly Dipeptide Noopept.

Vakhitova YV, Sadovnikov SV, Borisevich SS, Ostrovskaya RU, A Gudasheva T, Seredenin SB - Acta Naturae (2016 Jan-Mar)

Hypoxia-induced factor HIF-1 and its targets. Modified according to [24]
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4837574&req=5

Figure 4: Hypoxia-induced factor HIF-1 and its targets. Modified according to [24]
Mentions: The factor induced by hypoxia (HIF-1) is a heterodimer composed of twosubunits: a HIF-1α subunit sensitive to oxygen and constitutivelyexpressed HIF-1β. Hypoxia promotes an increase in the HIF-1α level,its dimeriation with HIF-1β, mobilization of coactivators (p300/CBP), andbinding of this complex to HRE (hypoxia-response element) in the regulatoryregions of target genes. In normoxic conditions, oxygen-dependent hydroxylationof proline residues in the HIF- 1α molecule by prolyl hydroxylases isnecessary for binding by the component of ubiquitin-protein ligase E3, vonHippel-Lindau (VHL) protein. Ubiquitinated HIF-1α becomes a target fordegradation by 26S proteasomes. The asparagine residue at the C-terminaltransactivation domain (C-TAD) of HIF-1α is hydroxylated by asparaginhydroxylase (FIH1, factor inhibiting HIF-1) in the presence of oxygen, therebyblocking its interaction with the transcriptional coactivator p300/CBP. Thus,PHD and FIH inactivate HIF-1α in normoxia, suppressing HIF-1-dependentexpression of the target genes. PHD and FIH activity decreases under conditionsof hypoxia, leading to a decrease in HIF-1α degradation andtranscriptional activation of its dependent genes[24]. It has been shown[25] that HIF-1 activates a total of up to 100genes. Figure 4 presentsthe main targets of HIF-1, which includethe genes involved in angiogenesis through activation of the vascular endothelialgrowth factor, enhanced synthesis of erythropoietin, activation of the systemsof glucose transport through membranes, cytoprotection by neurotrophic factors,normalization of cell cycle and metabolism at the mitochondrial level, as wellas the activity of antioxidant enzymes: superoxide dismutase and catalase. Thecombination of these effects allows the implementation of an adaptive responseto hypoxic exposure. Alongside with this, HIF-1 affects the state of manyneurotransmitter systems: it activates the protein responsible for control ofGABA receptors (GABARBP) [26] andincreases tyrosine hydroxylase activity [27].The close relation between HIF-1 and cholinergicreceptors has been described [28].

Bottom Line: Piracetam (1 mM) failed to affect significantly any of the TF under study.The results of molecular docking showed that Noopept (L-isomer), as well as its metabolite, L-isomer of N-phenyl-acetylprolyl, unlike its pharmacologically ineffective D-isomer, is able to bind to the active site of prolyl hydroxylase 2.The obtained data allow one to propose the HIF-positive effect as the primary mechanism of the activity of this Pro-Gly-containing dipeptide.

View Article: PubMed Central - PubMed

Affiliation: State Zakusov Institute of Pharmacology , Baltiyskaya Str., 8, 125315, Moscow, Russia ; Institute of Biochemistry and Genetics of Ufa Scientific Centre RAS, Prospekt Oktyabrya, 71, 450065 , Ufa, Russia.

ABSTRACT
This study was performed in order to reveal the effect of Noopept (ethyl ester of N-phenylacetyl-Lprolylglycine, GVS-111) on the DNA-binding activity of transcriptional factors (TF) in HEK293 cells transiently transfected with luciferase reporter constructs containing sequences for CREB, NFAT, NF-κB, p53, STAT1, GAS, VDR, HSF1, and HIF-1. Noopept (10 μM) was shown to increase the DNA-binding activity of HIF-1 only, while lacking the ability to affect that of CREB, NFAT, NF-κB, p53, STAT1, GAS, VDR, and HSF1. Noopept provoked an additional increase in the DNA-binding activity of HIF-1 when applied in conditions of CoCl2-induced HIF- 1 stabilization. The degree of this HIF-positive effect of Noopept was shown to be concentration-dependent. Piracetam (1 mM) failed to affect significantly any of the TF under study. The results of molecular docking showed that Noopept (L-isomer), as well as its metabolite, L-isomer of N-phenyl-acetylprolyl, unlike its pharmacologically ineffective D-isomer, is able to bind to the active site of prolyl hydroxylase 2. Taking into account the important role of the genes activated by HIF-1 in the formation of an adaptive response to hypoxia, data on the ability of Noopept to provoke a selective increase in the DNA-binding activity of HIF-1 explain the wide spectrum of neurochemical and pharmacological effects of Noopept revealed before. The obtained data allow one to propose the HIF-positive effect as the primary mechanism of the activity of this Pro-Gly-containing dipeptide.

No MeSH data available.


Related in: MedlinePlus