NobleBlocks

H.Buniatian Institute of Biochemistry

facilityYerevan, Armenia

Research output, citation impact, and the most-cited recent papers from H.Buniatian Institute of Biochemistry (Armenia). Aggregated across the NobleBlocks index of 300M+ scholarly works.

Total works
198
Citations
3.5K
h-index
26
i10-index
110
Also known as
H.Buniatian Institute of Biochemistry

Top-cited papers from H.Buniatian Institute of Biochemistry

Regional organizations and the resolution of internal conflict: The ECOWAS intervention in Liberia
W. Ofuatey‐Kodjoe
1994· International Peacekeeping36doi:10.1080/13533319408413509

For over two years, the ECOWAS intervention in Liberia went through many difficult phases. Finally, on 24 July 1993, ECOWAS was able to negotiate the Cotonou Agreement, with the assistance of the UN and the OAU. By this agreement, the warring factions agreed to a ceasefire, the disarmament and encampment of their forces, the establishment of a transitional government in which they will participate, and free elections within a seven month period leading to the establishment of democratic government in Liberia. In spite of some sporadic violations, the ceasefire seems to be holding, and the transitional government is on the way to becoming operational. This article examines the roots of the Liberian conflict and evaluates the performance of the ECOWAS intervention. It suggests that there are lessons to be learned about the potential role of regional organizations in dealing with intrastate conflicts.

Influence of dipeptidyl peptidase IV on enzymatic properties of adenosine deaminase.
Svetlana Sharoyan, Alvard Antonyan, Sona Mardanyan, Giulio Lupidi +1 more
2006· Acta Biochimica Polonica33doi:10.18388/abp.2006_3325

The importance of ADA (adenosine deaminase) in the immune system and the role of its interaction with an ADA-binding cell membrane protein dipeptidyl peptidase IV (DPPIV), identical to the activated immune cell antigen, CD26, has attracted the interest of researchers for many years. To investigate the specific properties in the structure-function relationship of the ADA/DPPIV-CD26 complex, its soluble form, identical to large ADA (LADA), was isolated from human blood serum, human pleural fluid and bovine kidney cortex. The kinetic constants (Km and Vmax) of LADA and of small ADA (SADA), purified from bovine lung and spleen, were compared using adenosine (Ado) and 2'-deoxyadenosine (2'-dAdo) as substrates. The Michaelis constant, Km, evidences a higher affinity of both substrates (in particular of more toxic 2'-dAdo) for LADA and proves the modulation of toxic nucleoside neutralization in the extracellular medium due to complex formation between ADA and DPPIV-CD26. The values of Vmax are significantly higher for SADA, but the efficiency, Vmax/Km, in LADA-catalyzed 2'-dAdo deamination is higher than that in Ado deamination. The interaction of all enzyme preparations with derivatives of adenosine and erythro-9-(2-hydroxy-3-nonyl)adenine (EHNA) was studied. 1-DeazaEHNA and 3-deazaEHNA demonstrate stronger inhibiting activity towards LADA, the DPPIV-CD26-bound form of ADA. The observed differences between the properties of the two ADA isoforms may be considered as a consequence of SADA binding with DPPIV-CD26. Both SADA and LADA indicated a similar pH-profile of adenosine deamination reaction with the optimum at pHs 6.5-7.5, while the pH-profile of dipeptidyl peptidase activity of the ADA/DPPIV-CD26 complex appeared in a more alkaline region.

Lignan from Thyme Possesses Inhibitory Effect on ASIC3 Channel Current
Maxim A. Dubinnyi, Dmitry I. Osmakov, Sergey G. Koshelev, Sergey A. Kozlov +4 more
2012· Journal of Biological Chemistry32doi:10.1074/jbc.m112.366427

A novel compound was identified in the acidic extract of Thymus armeniacus collected in the Lake Sevan region of Armenia. This compound, named “sevanol,” to our knowledge is the first low molecular weight natural molecule that has a reversible inhibition effect on both the transient and the sustained current of human ASIC3 channels expressed in Xenopus laevis oocytes. Sevanol completely blocked the transient component (IC50 353 ± 23 μm) and partially (∼45%) inhibited the amplitude of the sustained component (IC50 of 234 ± 53 μm). Other types of acid-sensing ion channel (ASIC) channels were intact to sevanol application, except ASIC1a, which showed more than six times less affinity to it as compared with the inhibitory action on the ASIC3 channel. To elucidate the structure of sevanol, the set of NMR spectra in two solvents (d6-DMSO and D2O) was collected, and the complete chemical structure was confirmed by liquid chromatography-mass spectrometry with electrospray ionization (LC-ESI+-MS) fragmentation. This compound is a new lignan built up of epiphyllic acid and two isocitryl esters in positions 9 and 10. In vivo administration of sevanol (1–10 mg/kg) significantly reversed thermal hyperalgesia induced by complete Freund's adjuvant injection and reduced response to acid in a writhing test. Thus, we assume the probable considerable role of sevanol in known analgesic and anti-inflammatory properties of thyme. A novel compound was identified in the acidic extract of Thymus armeniacus collected in the Lake Sevan region of Armenia. This compound, named “sevanol,” to our knowledge is the first low molecular weight natural molecule that has a reversible inhibition effect on both the transient and the sustained current of human ASIC3 channels expressed in Xenopus laevis oocytes. Sevanol completely blocked the transient component (IC50 353 ± 23 μm) and partially (∼45%) inhibited the amplitude of the sustained component (IC50 of 234 ± 53 μm). Other types of acid-sensing ion channel (ASIC) channels were intact to sevanol application, except ASIC1a, which showed more than six times less affinity to it as compared with the inhibitory action on the ASIC3 channel. To elucidate the structure of sevanol, the set of NMR spectra in two solvents (d6-DMSO and D2O) was collected, and the complete chemical structure was confirmed by liquid chromatography-mass spectrometry with electrospray ionization (LC-ESI+-MS) fragmentation. This compound is a new lignan built up of epiphyllic acid and two isocitryl esters in positions 9 and 10. In vivo administration of sevanol (1–10 mg/kg) significantly reversed thermal hyperalgesia induced by complete Freund's adjuvant injection and reduced response to acid in a writhing test. Thus, we assume the probable considerable role of sevanol in known analgesic and anti-inflammatory properties of thyme.

Losartan Improves Memory, Neurogenesis and Cell Motility in Transgenic Alzheimer’s Mice
Henning Johannes Drews, Roman Klein, Ali Lourhmati, Marine Buadze +4 more
2021· Pharmaceuticals29doi:10.3390/ph14020166

Angiotensin receptor blockers (ARBs) have demonstrated multiple neuroprotective benefits in Alzheimer’s disease (AD) models. However, their beneficial effects on memory deficits, cholinergic activity, neurogenesis and Amyloid beta (Aβ) clearance reveal significant interstudy variability. The delivery route can impact not only delivery but also targeting and therapeutic efficacy of ARBs. Our previous findings on the beneficial effects of intranasally delivered losartan in the APP/PS1 model of AD prompted us to explore the influence of the delivery route by employing here the systemic administration of losartan. Consistent with our previous results with intranasal losartan, repeated intraperitoneal administration (10 mg/kg) resulted in a remarkable decrease in Aβ plaques and soluble Aβ42, as well as inflammatory cytokines (IL-2, IL-6 and TNFα). The Aβ reduction can be ascribed to its facilitated degradation by neprilysin and diminished generation by BACE1. Losartan increased neurogenesis in vivo and in vitro and improved migratory properties of astrocytes isolated from adult transgenic AD mice. In summary, this data together with our previous results suggest therapeutic features of losartan which are independent of delivery route. The improvement of cell motility of Aβ-affected astrocytes by losartan deserves further in vivo investigation, which may lead to new strategies for AD treatment.

QSAR Analysis for ADA upon Interaction with a Series of Adenine Derivatives as Inhibitors
Ali Akbar Moosavi‐Movahedi, Shahrokh Safarian, G. H. HAKIMELAHI, G.H. Ataei +4 more
2004· Nucleosides Nucleotides & Nucleic Acids28doi:10.1081/ncn-120030719

The kinetic parameters of adenosine deaminase such as Km and Ki were determined in the absence and presence of adenine derivatives (R1-R24) in sodium phosphate buffer (50 mM; pH 7.5) solution at 27 degrees C. These kinetic parameters were used for QSAR analysis. As such, we found some theoretical descriptors to which the binding affinity of adenosine deaminase (ADA) towards several adenine nucleosides as inhibitors is correlated. QSAR analysis has revealed that binding affinity of the adenine nucleosides upon interaction with ADA depends on the molecular volume, dipole moment of the molecule, electric charge around the N1 atom, and the highest of positive charge for the related molecules.

Spinal cord degeneration in C57BL/6N mice following induction of experimental parkinsonism with MPTP
Supriti Samantaray, Varduhi H. Knaryan, Jonathan T. Butler, Swapan K. Ray +1 more
2007· Journal of Neurochemistry26doi:10.1111/j.1471-4159.2007.05091.x

We examined neurodegeneration in spinal cord (SC) and role of such extra-nigral degeneration in MPTP-induced experimental parkinsonism in C57BL/6N mice. HPLC-photodiode array analysis confirmed presence of the active neurotoxin MPP+ in SC after single injection of MPTP (25 mg/kg, i.p.). Mitochondrial enzyme monoamine oxidase-B (MAO-B) responsible for in vivo conversion of MPTP to MPP+ was inhibited in SC by pre-treatment with l-deprenyl, a specific inhibitor of MAO-B. Besides in vitro conversion of MPTP to MPP+ occurred by SC mitochondrial preparation, which was inhibited by l-deprenyl implicating SC as a specific target of MPTP-neurotoxicity. Double immunofluorescent labeling and spectrofluorimetric assay via kynuramine oxidation showed MAO-B expression and activity in SC neurons. Localization of dopamine transporter immunoreactivity in SC along with specific uptake of (3)H-MPP+ by SC synaptosomal preparation further confirmed SC as target of MPTP-neurotoxicity. Compared with control, increased neuronal death on the seventh day in SC of mice injected with MPTP (2 x 25 mg/kg, at 6 h interval) strongly suggested SC degeneration in pre-symptomatic phase of MPTP-induced experimental parkinsonism. Such extra-nigral neurodegeneration in Parkinson's disease indicated novel molecular mechanism preceding nigrostriatal degeneration and suggested designing broad therapeutic intervention for this complex movement disorder.

Effects of stevia on synaptic plasticity and NADPH oxidase level of CNS in conditions of metabolic disorders caused by fructose
V. A. Chavushyan, K. V. Simonyan, R. M. Simonyan, A. S. Isoyan +4 more
2017· BMC Complementary and Alternative Medicine26doi:10.1186/s12906-017-2049-9

Excess dietary fructose intake associated with metabolic syndrome and insulin resistance and increased risk of developing type 2 diabetes. Previous animal studies have reported that diabetic animals have significantly impaired behavioural and cognitive functions, pathological synaptic function and impaired expression of glutamate receptors. Correction of the antioxidant status of laboratory rodents largely prevents the development of fructose-induced plurimetabolic changes in the nervous system. We suggest a novel concept of efficiency of Stevia leaves for treatment of central diabetic neuropathy. By in vivo extracellular studies induced spike activity of hippocampal neurons during high frequency stimulation of entorhinal cortex, as well as neurons of basolateral amygdala to high-frequency stimulation of the hippocampus effects of Stevia rebaudiana Bertoni plant evaluated in synaptic activity in the brain of fructose-enriched diet rats. In the conditions of metabolic disorders caused by fructose, antioxidant activity of Stevia rebaudiana was assessed by measuring the NOX activity of the hippocampus, amygdala and spinal cord. In this study, the characteristic features of the metabolic effects of dietary fructose on synaptic plasticity in hippocampal neurons and basolateral amygdala and the state of the NADPH oxidase (NOX) oxidative system of these brain formations are revealed, as well as the prospects for development of multitarget and polyfunctional phytopreparations (with adaptogenic, antioxidant, antidiabetic, nootropic activity) from native raw material of Stevia rebaudiana. Stevia modulates degree of expressiveness of potentiation/depression (approaches but fails to achieve the norm) by shifting the percentage balance in favor of depressor type of responses during high-frequency stimulation, indicating its adaptogenic role in plasticity of neural networks. Under the action of fructose an increase (3–5 times) in specific quantity of total fraction of NOX isoforms isolated from the central nervous system tissue (amygdala, hippocampus, spinal cord) was revealed. Stevia exhibits an antistress, membrane-stabilizing role reducing the level of total fractions of NOX isoforms from central nervous system tissues and regulates NADPH-dependent O2 − −producing activity. Generally, in condition of metabolic disorders caused by intensive consumption of dietary fructose Stevia leaves contributes to the control of neuronal synaptic plasticity possibly influencing the conjugated NOX-specific targets.

Synthesis, Antitumor Activity, and Docking Analysis of New Pyrido[3′,2′:4,5]furo(thieno)[3,2-d]pyrimidin-8-amines
Samvel N. Sirakanyan, Domenico Spinelli, Athina Geronikaki, Elmira K. Hakobyan +4 more
2019· Molecules25doi:10.3390/molecules24213952

Continuing our research in the field of new heterocyclic compounds, herein we report on the synthesis and antitumor activity of new amino derivatives of pyrido[3′,2′:4,5](furo)thieno[3,2-d]pyrimidines as well as of two new heterocyclic systems: furo[2–e]imidazo[1,2-c]pyrimidine and furo[2,3-e]pyrimido[1,2-c]pyrimidine. Thus, by refluxing the 8-chloro derivatives of pyrido[3′,2′:4,5]thieno(furo)[3,2-d]pyrimidines with various amines, the relevant pyrido[3′,2′:4,5]thieno(furo)[3,2-d]pyrimidin-8-amines were obtained. Further, the cyclization of some amines under the action of phosphorus oxychloride led to the formation of new heterorings: imidazo[1,2-c]pyrimidine and pyrimido[1,2-c]pyrimidine. The possible antitumor activity of the newly synthesized compounds was evaluated in vitro. The biological tests evidenced that some of them showed pronounced antitumor activity. A study of the structure–activity relationships revealed that the compound activity depended mostly on the nature of the amine fragments. A docking analysis was also performed for the most active compounds.

ADA2 isoform of adenosine deaminase from pleural fluid
N. A. Andreasyan, H. L. Hairapetyan, Yelizaveta Sargisova, Sona Mardanyan
2004· FEBS Letters22doi:10.1016/j.febslet.2004.11.109

Adenosine deaminase isoenzyme 2 (ADA2) was isolated from human pleural fluid for the first time. Molecular and kinetic properties were characterized. It was shown that the inhibitors of adenosine deaminase isoenzyme 1 (ADA1), adenosine, and erithro-9-(2-hydroxy-3-nonyl)adenine (EHNA) derivatives are poor inhibitors of ADA2. Comparison of the interaction of ADA2 and ADA1 with adenosine and its derivative, 1-deazaadenosine, indicates that the isoenzymes have similar active centers. The absence of ADA2 inhibition by EHNA is evidence of a difference of these active centers in a close environment. The possible role of Zn2+ ions and the participation of acidic amino acids Glu and Asp in adenosine deamination catalyzed by ADA2 were shown.

α2-Adrenergic Receptor in Liver Fibrosis: Implications for the Adrenoblocker Mesedin
Ute Schwinghammer, Magda M. Melkonyan, Lilit Hunanyan, Roman Tremmel +4 more
2020· Cells19doi:10.3390/cells9020456

The noradrenergic system is proposed to play a prominent role in the pathogenesis of liver fibrosis. While α1- and β-adrenergic receptors (ARs) are suggested to be involved in a multitude of profibrogenic actions, little is known about α2-AR-mediated effects and their expression pattern during liver fibrosis and cirrhosis. We explored the expression of α2-AR in two models of experimental liver fibrosis. We further evaluated the capacity of the α2-AR blocker mesedin to deactivate hepatic stellate cells (HSCs) and to increase the permeability of human liver sinusoidal endothelial cells (hLSECs). The mRNA of α2a-, α2b-, and α2c-AR subtypes was uniformly upregulated in carbon tetrachloride-treated mice vs the controls, while in bile duct-ligated mice, only α2b-AR increased in response to liver injury. In murine HSCs, mesedin led to a decrease in α-smooth muscle actin, transforming growth factor-β and α2a-AR expression, which was indicated by RT-qPCR, immunocytochemistry, and Western blot analyses. In a hLSEC line, an increased expression of endothelial nitric oxide synthase was detected along with downregulated transforming growth factor-β. In conclusion, we suggest that the α2-AR blockade alleviates the activation of HSCs and may increase the permeability of liver sinusoids during liver injury.

Activity of adenosine deaminase and its isoforms in pleural fluid in tuberculous pleuritis.
N. A. Andreasyan, Hripsime L. Hairapetian, Yelizaveta Sargisova, Sona Mardanyan +2 more
2002· PubMed18

BACKGROUND: The problem of tuberculosis is increasing in a number of countries. Adenosine deaminase activity is considered in many clinics to be a valuable biochemical test of this pathology. Considerable research has been devoted to the activity of enzyme isoforms as significant tests for diagnosing tuberculosis. The aim of our study was to compare the significance of different adenosine deaminase dependent parameters in diagnosing tuberculosis. MATERIAL/METHODS: The level of adenosine deaminase and the activity of its two isoenzymes in the pleural fluids of patients with tuberculous and non-tuberculous pleurisy were compared. RESULTS: The adenosine deaminase level in tuberculous pleural effusions was higher than in non-tuberculous pleural effusions. The data we obtained suggest that the enzyme activity level could be a very reliable test in the differential diagnosis of tuberculous pleurisy in the Armenian population. The activity of isoenzymes ADA1 and ADA2, or their ratios to the total ADA activity, though valuable information, has no diagnostic advantage over total ADA activity in diagnosing this pathology. CONCLUSIONS: The results clearly point up the value of using a total ADA activity assay in Armenian clinics for the differential diagnosis of tuberculous pleurisy. Determinations of the activity level of the ADA1 and ADA2 isoenzymes provide no diagnostic advantage over total ADA activity.

Hypothalamic Proline-Rich Polypeptide Is a Regulator of Oxidative Burst in Human Neutrophils and Monocytes
Tigran K. Davtyan, Hayk A. Manukyan, Nana R. Mkrtchyan, Samvel A. Avetisyan +1 more
2005· NeuroImmunoModulation18doi:10.1159/000087105

OBJECTIVE: The effects of proline-rich polypeptide (PRP) isolated from neurosecretory granules of bovine neurohypophysis produced by nuclei supraopticus and paraventricularis on phagocytosis, bacterial intracellular killing and oxidative burst induction in normal human cells and inflammatory cells from patients with Behçet's disease (BD), i.e. peripheral blood neutrophils and monocytes, were investigated. METHODS: Intracellular killing of Staphylococcus aureus by neutrophils and monocytes of normal controls and BD patients, phagocytic activity as well as spontaneous and N-formyl-Met-Leu-Phe (fMLP)- or phorbol 12-myristate 13-acetate (PMA)-induced activation of their respiratory burst were determined by quantitative flow cytometry using highly specific fluorescence probes. RESULTS: PRP does not affect human peripheral blood neutrophil and monocyte phagocytosis but dramatically enhances spontaneous or fMLP- and PMA-induced oxidative burst as well as the intracellular killing of S. aureus. PRP induced the upregulation of the spontaneous or fMLP- and PMA-induced oxidative burst in normal PMNs and monocytes; the number of inflammatory BD cells did neither increase further nor undergo spontaneous or PMA-stimulated oxidative burst. In BD patients, increased spontaneous production of reactive oxygen intermediates (ROIs) by neutrophils and monocytes is characterized by impaired intracellular protein-kinase-C (PKC)-dependent oxidative burst regulation as well as over-regulation of chemotaxis/inflammation-mediated respiratory burst induction. PRP restores rather the impaired intracellular PKC-dependent regulation of ROI production in inflammatory diseased cells than the chemotaxis/induction of the inflammation-mediated respiratory burst. CONCLUSION: We demonstrated the regulatory role for PRP on oxidative burst in neutrophils and monocytes from normal controls and BD patients. Our results suggest that PRP differentially affects both chemotaxis- and PKC-dependent oxidative burst in normal and inflammatory cells from patients.

Toll like receptors TLR1/2, TLR6 and MUC5B as binding interaction partners with cytostatic proline rich polypeptide 1 in human chondrosarcoma
Karina Galoian, S. S. Abrahamyan, Gor Chailyan, Amir Qureshi +4 more
2017· International Journal of Oncology15doi:10.3892/ijo.2017.4199

Metastatic chondrosarcoma is a bone malignancy not responsive to conventional therapies; new approaches and therapies are urgently needed. We have previously reported that mTORC1 inhibitor, antitumorigenic cytostatic proline rich polypeptide 1 (PRP-1), galarmin caused a significant upregulation of tumor suppressors including TET1/2 and SOCS3 (known to be involved in inflammatory processes), downregulation of oncoproteins and embryonic stem cell marker miR-302C and its targets Nanog, c-Myc and Bmi-1 in human chondrosarcoma. To understand better the mechanism of PRP-1 action it was very important to identify the receptor it binds to. Nuclear pathway receptor and GPCR assays indicated that PRP-1 receptors are not G protein coupled, neither do they belong to family of nuclear or orphan receptors. In the present study, we have demonstrated that PRP-1 binding interacting partners belong to innate immunity pattern recognition toll like receptors TLR1/2 and TLR6 and gel forming secreted mucin MUC5B. MUC5B was identified as PRP-1 receptor in human chondrosarcoma JJ012 cell line using Ligand-receptor capture technology. Toll like receptors TLR1/2 and TLR6 were identified as binding interaction partners with PRP-1 by western blot analysis in human chondrosarcoma JJ012 cell line lysates. Immunocytochemistry experiments confirmed the finding and indicated the localization of PRP-1 receptors in the tumor nucleus predominantly. TLR1/2, TLR6 and MUC5B were downregulated in human chondrosarcoma and upregulated in dose-response manner upon PRP-1 treatment. Experimental data indicated that in this cellular context the mentioned receptors had tumor suppressive function.

Dipeptidyl peptidase IV and adenosine deaminase inhibition by Armenian plants and antidiabetic drugs
Sona Mardanyan, S. G. Sharoyan, Alvard Antonyan, Narine A. Zakaryan
2019· International Journal of Diabetes and Metabolism14doi:10.1159/000497713

Dipeptidyl peptidase IV (DPP-IV) converts glucagon-like peptide-1 (GLP-1)(7-36), responsible for glucose tolerance into inactive GLP-1(9-36). The pathogenic role of elevated adenosine deaminase (ADA) activity at hyperglycemic conditions was also suggested. Hence, the inhibition of both DPP-IV and ADA would be beneficial in the treatment of diabetes mellitus. Screening of the ability of water extracts of 23 Armenian Highland native plants to inhibit the enzymatic activity of DPP-IV and ADA was performed. Over 40% of DPP-IV and ADA activity inhibition was observed by 1 percent extracts from between 6 and 12 plants. Among them, the most effective inhibitor for DPP-IV inhibitor was the extract from the leaves of sea-buckthorn (Hippophaё rhamnoides) (80.5% ± 3.3; IC50 = 2.5mg/ml ± 0.03); and for ADA: from St. John's wort (Hypericum perforatum) (88.3% ±7.4; IC50 = 1.99mg/ml ± 0.3). Very slight ability of the known antidiabetic drugs, diabeton, glurenorm, siofor, glucovance, and the medicinal herbal mixture Arfazetin-A to inhibit the enzymes under study was observed. Moreover, the extracts from clove, cinnamon, green and black tea were highly effective in inhibiting DPP-IV and ADA. The obtained results show that selected Armenian Highland plants: blackberry, melilot; oregano, St. John's wort, sea-buckthorn leaves could be used, in combination with other antidiabetic drugs, for the treatment of diabetes mellitus.

Hypothalamic Proline-Rich Polypeptide Enhances Bone Marrow Colony-Forming Cell Proliferation and Stromal Progenitor Cell Differentiation
A. A. Galoyan, L. I. Korochkin, E. J. Rybalkina, Г. В. Павлова +4 more
2008· Cell Transplantation14doi:10.3727/096368908786991579

The AGAPEPAEPAQPGVY proline-rich peptide (PRP-1) was isolated from neurosecretory granules of the bovine neurohypophysis; it is produced by N. supraopticus and N. paraventricularis. It has been shown that PRP-1 has many potentially beneficial biological effects, including immunoregulatory, hematopoietic, antimicrobial, and antineurodegenerative properties. Here we showed that PRP increased colony-forming cell (CFC) proliferation in rat bone marrow (BM) cells in vivo. In PRP-treated rat BM, the CFU number at day 7 and day 14 was considerably increased in comparison with untreated rat BM and no difference was found at day 21 and day 28. The related peptide [arg8]vasopressin did not reveal CFC proliferation. PRP failed to farther increase CFC proliferation in vitro in BM obtained from PRP-treated or untreated rats. After 3-4 days of human BM stromal cell cultivation in the presence of 2-20 microg/ml PRP the appearance of cells expressing CD15, CD10, CD11a, CD11b, CD3, CD4, and CD16 surface antigens did not differ from the untreated cells. PRP increased the appearance of CD14-positive cells upon 3-4-day incubation with both adult and fetal BM stromal cells. Our results suggest a previously undescribed role for the hypothalamic peptide within neurosecretory hypothalamus-bone marrow humoral axis, because PRP enhances BM colony-forming cell proliferation and stromal cell differentiation.

Antifibrotic Effects of Amyloid-Beta and Its Loss in Cirrhotic Liver
Gayane Hrachia Buniatian, Ralf Weiskirchen, Thomas S. Weiß, Ute Schwinghammer +4 more
2020· Cells13doi:10.3390/cells9020452

The function and regulation of amyloid-beta (Aβ) in healthy and diseased liver remains unexplored. Because Aβ reduces the integrity of the blood-brain barrier we have examined its potential role in regulating the sinusoidal permeability of normal and cirrhotic liver. Aβ and key proteins that generate (beta-secretase 1 and presenilin-1) and degrade it (neprilysin and myelin basic protein) were decreased in human cirrhotic liver. In culture, activated hepatic stellate cells (HSC) internalized Aβ more efficiently than astrocytes and HSC degraded Aβ leading to suppressed expression of α-smooth muscle actin (α-SMA), collagen 1 and transforming growth factor β (TGFβ). Aβ also upregulated sinusoidal permeability marker endothelial NO synthase (eNOS) and decreased TGFβ in cultured human liver sinusoidal endothelial cells (hLSEC). Liver Aβ levels also correlate with the expression of eNOS in transgenic Alzheimer's disease mice and in human and rodent cirrhosis/fibrosis. These findings suggest a previously unexplored role of Aβ in the maintenance of liver sinusoidal permeability and in protection against cirrhosis/fibrosis via attenuation of HSC activation.

Food security issues in the economic security system of the Republic of Armenia
Meri Manucharyan
2021· BIO Web of Conferences12doi:10.1051/bioconf/20213608004

One of the most important components of national security is food security. The country's food security is mainly ensured through the development of agriculture, food production and food import systems. The main problems of the development of the agri-food system of the republic were the increase of the level of provision of the population with food, the increase of the level of economic protection of the country, which, first of all, requires an increase of agricultural production to provide the population with locally produced food products, raw materials to the processing industry as much as possible, as well as to increase export volumes. The main goal of the research is to develop and outline the ways of further development of the RA food self-sufficiency based on the development of agricultural production. Based on the analysis of the current situation in the agricultural market, to propose a set of economic development measures, which will contribute to the increase of the food security level, the development of the agri-food system, the reduction of the poverty level of the rural communities. The research substantiated the preconditions for further growth of agricultural production, as a result of comprehensive studies and analyzes, the main directions of improving food production and increasing efficiency were outlined, which conditioned the scientific novelty.

The role of singlet oxygen and hydroxyl radical in the photobleaching of meso-substituted cationic pyridyl porphyrins in the presence of folic acid
L. V. Mkrtchyan, Torgom Seferyan, Marina V. Parkhats, С. В. Лепешкевич +4 more
2024· Journal of Innovative Optical Health Sciences12doi:10.1142/s1793545824400029

Using a photosensitizer (PS), light, and oxygen, photodynamic therapy creates cytotoxic reactive oxygen species, such as singlet oxygen ( 1 O 2 ), that kill cancer cells. Many cancer cell lines have up to 300 times more folic acid receptors than healthy cells. Therefore, folic acid is often used to improve selectivity of PSs. Photobleaching poses a disadvantage for PSs. In this paper, we have studied the photoinduced changes of meso-substituted cationic pyridyl porphyrins in the presence of folic acid using fluorescence and absorption spectroscopy. In this work, it was demonstrated that L-histidine, which is a 1 O 2 quencher, and D-mannitol, which is a hydroxyl radical quencher, can reduce photobleaching of cationic porphyrins and their interaction products with FA. This implies both singlet oxygen and hydroxyl radicals are involved in photobleaching. Additionally, our study revealed certain important features of the photobleaching of cationic porphyrins in the presence of folic acid.

NADPH containing superoxide-producing thermostable complex from raspberry, apricot, grape, and grape seeds: isolation, purification, and properties
Sona M. Feschyan, R. M. Simonyan, G. M. Simonyan, M. A. Simonyan +1 more
2023· Plant Methods12doi:10.1186/s13007-022-00978-9

Abstract Background NADPH oxidase (Nox) plays a crucial role in reactive oxygen spices (ROS) production and mediates different diseases’ development. Under aerobic conditions, the NADPH-containing protein component of the (NCP)-Fe (III) complex produces O 2 − continuously and intensively. However, after the removal of Fe (III), the isolated NCP shows only antioxidant properties at the expense of NADPH composite. Based on the fact that the mentioned fruit juices are widely used in everyday life and also in biomedicine, it was aimed to use a universal method: 1. to obtain superoxide generating complex from available and relatively cheap raw materials without using any toxic substances; 2. to isolate, purify and study the components of prooxidant nature: the isoforms of O 2 − —producing NCP-Fe (III) complexes obtained from Armenian fruits (raspberries, apricot, grapes), as well, grape seeds. Results Using a licensed method, for the first time isoforms of the superoxide (O 2 − ) producing a thermostable complex of the NCP component with Fe (III), (NCP-Fe (III)), were isolated and purified from Armenian fruits—raspberries, apricots, grapes, and grapes seeds. The process of isolation and purification of isoforms of these complexes included the following stages of processing: 1. alkaline hydrolysis at pH9,5; 2. their sedimentation at pH4.8; 3. Dissolving of the sediments in water at pH9.5, followed by ion-exchange chromatography on cellulose DE-52, and gel filtration on Sephadex G-100. Further, the heat treatment of the mentioned complexes was carried out. In a lyophilized state, under the anaerobic conditions, the isoforms of the given complexes, hybrid associates (hNCP-Nox), and NCP were stored practically without losing their activity in a mass of 1–1.5 g. Conclusions Isoforms of O 2 − -producing complexes are new liquid-phase, thermo-stable prooxidant components found in raspberries, apricots, grapes, and grapes seeds.

Superoxide-producing lipoprotein fraction from Stevia leaves: definition of specific activity
A. S. Isoyan, K. V. Simonyan, R. M. Simonyan, M. A. Babayan +3 more
2019· BMC Complementary and Alternative Medicine11doi:10.1186/s12906-019-2500-1

Stevia rebaudiana Bertoni has various pharmacological actions, which includes antidiabetic, antioxidant, anti-inflammatory activities. The superoxide and consequently NADPH oxidase (Nox) are relevant targets involved in biological effects of Stevia. The presence of NADPH-containing superoxide-producing lipoprotein (suprol) in Stevia leaves has not yet been tested. The mechanism of producing superoxide radicals (O2−) by suprol was determined in vitro, which is associated with the electron transfer from NADPH in the composition of suprol by traces of transition metal ions (Fe3+ or Cu2+) to molecular oxygen, turning it into O2−. It is expected that the therapeutic efficacy of Stevia leaves is caused by specific activity of superoxide-producing lipoprotein fraction. For the first time, from the dry leaves of Stevia the NADPH-containing superoxide-producing lipoprotein was isolated and purified. The specific content of suprol (milligrams in 1 g of Stevia leaves- mg/g) was determined after desalination of suprol and lyophilization. According to the method provided, the specific content of the isolated suprol from Stevia’s leaves was up to 4.5 ± 0.2 mg / g (yields up to 68.5 ± 4.7%, p < 0.05, n = 6). Nox forms a stable complex with suprol. The optical absorption spectrum of the Nox-suprol complex represents the overlapping suprol and Nox spectra, with a certain background increase and characteristic features of optical absorption for Nox. Due to O2− producing capacity suprol-Nox complex discolors KMnO4 solutions, Coomassie brilliant blue, restores nitrotetrazolium blue to formazan and oxidizes epinephrine to adrenochrome. The oxidation activity of adrenaline is 50.3 ± 5.1 U / mg / ml (p < 0.05, n = 6). Superoxide-producing lipoprotein fraction-Nox complex from Stevia leaves (membranes) can modulate redox regulated signaling pathways and may play a positive role in type-2 diabetes by means of adrenaline oxidation mechanism.