Konstantin YenkoyanYerevan State Medical University | YSMU · Neurosciecne Laboratory and Department of Biochemistry
Konstantin Yenkoyan
Professor
About
50
Publications
5,186
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
345
Citations
Citations since 2017
Introduction
Konstantin Yenkoyan, MD, PhD, Professor. Currently Vice-rector for Science, Head the Neuroscience Laboratory and Professor of Biochemistry Department of YSMU. Konstantin does research in Neuroscienc and, Biochemistry. Research focus - neurodegeneration and neuronal survival, Alzheimer disease, neurodevelopmental disorders, Autism. PI of Horizon 2020 - COBRAIN Project, Coordinator of YSMU team in HORIZON 2020 SCAUT project.
Publications
Publications (50)
Perinatal depression is the most common psychiatric complication of pregnancy, with its detrimental effects on maternal and infant health grossly underrated. There is a pressing need for specific molecular biomarkers, with a pregnancy-related decline in brain-derived neurotrophic factor (BDNF) in the blood and downregulation of TrkB receptor in the...
Alzheimer’s disease (AD) is the most prevalent neurodegenerative disorder and warrants further study as well as timely treatment. Additionally, the mechanisms of the brain’s intrinsic defense against chronic injury are not yet fully understood. Herein, we examined the response of the main neurogenic niches to amyloid exposure and the associated cha...
Blood spotted onto filter paper can be easily collected outside healthcare facilities and shipped to a central laboratory for serological testing. However, dried blood testing generally requires manual processing for pre-analytical steps. In this study, we used a standardized blood collection device combined with an automated elution system to test...
Alzheimer’s disease (AD) is a type of dementia that affects memory, thinking and behavior. Symptoms eventually become severe enough to interfere with daily tasks. Understanding the etiology and pathogenesis of AD is necessary for the development of strategies for AD prevention and/or treatment, and modeling of this pathology is an important step in...
The comprehension of a long-term humoral immune response against SARS-CoV-2 can shed light on the treatment and vaccination strategies of COVID-19 disease, improving the knowledge about this virus infection and/or re-infection. We assessed the IgG antibodies against SARS-CoV-2 nucleocapsid (N) protein (anti-SARS-CoV-2 (N) IgG) in 1441 COVID-19 conv...
Background and objectives:
Neurological manifestations of Coronavirus Disease 2019 (COVID-19) such as olfactory and gustatory disturbance have been reported among convalescent COVID-19 patients. However, scientific data on the prevalence of smell and taste disturbance are lacking. Therefore, we present findings on the degree of smell and taste dis...
Hallucinogenic drugs potently affect brain and behavior and have also recently emerged as potentially promising agents in pharmacotherapy. Complementing laboratory rodents, the zebrafish (Danio rerio) is a powerful animal model organism for screening neuroactive drugs, including hallucinogens. Here, we test a battery of ten novel N-benzyl-2-phenyle...
Background
Neurological COVID-19 disease has been reported widely, but published studies often lack information on neurological outcomes and prognostic risk factors. We aimed to describe the spectrum of neurological disease in hospitalised COVID-19 patients; characterise clinical outcomes; and investigate factors associated with a poor outcome.
Me...
Background
Blood spotted onto filter paper can be easy collected outside healthcare facilities and shipped to central laboratory for serological testing. However, dried blood testing generally requests manual processing for elution. In this study, we used a standardized blood collection device combined with an automatized elution system to test ill...
Neurodegeneration is a major cause of Alzheimer's, Parkinson's, Huntington's, multiple and amyotrophic lateral sclerosis, pontocerebellar hypoplasia, dementia and other brain disorders. Their complex pathogenesis commonly includes genetic and neurochemical deficits, misfolded protein toxicity, demyelination, apoptosis and mitochondrial dysfunctions...
Brain tissue biobanks represent specific collections and ensure investigation and research into neurological and psychiatric diseases. Depending on the research question, scientists can use post-mortem biospecimens or, more rarely, samples from living donors. Generally, there are post-mortem samples, which are retrieved during autopsy. However, any...
This book introduces the fundamentals of biobanking and guides through the practical
planning thereof, with a special focus on the situation in low- and middle-income countries. On the example of the setup of a Ukrainian biobank the book discusses the main steps and aspects of successful biorepository implementation and management. Topics covered i...
Autism Spectrum Disorder (ASD) is characterized by persistent deficits in social communication and restricted-repetitive patterns of behavior, interests, or activities. ASD is generally associated with chronic inflammatory states, which are linked to immune system dysfunction and/or hyperactivation. The latter might be considered as one of the fact...
Autism spectrum disorders (ASD) are neurodevelopmental disorders, that are characterized by core symptoms, such as alterations of social communication and restrictive or repetitive behavior. The etiology and pathophysiology of disease is still unknown, however, there is a strong interaction between genetic and environmental factors. An intriguing p...
Introduction
Analyser la prévalence, la durée et les facteurs associés de la réponse humoral anti SARS-CoV-2 dans un pays européen (Arménie).
Patients et méthodes
Etude prospective nationale en Arménie, avec 1441 patients ayant eu une infection prouvée à Cov-19 (PCR positive).
Résultats
1441 SARS-CoV-2 patients, dont 74,1 % femmes (n = 1004 patie...
The comprehension of a long-term humoral immune response against the SARS-CoV-2 virus can shed light on the treatment and vaccination of the disease, improve the control of the pandemic infection. We assessed the antibodies against SARS-CoV-2 nucleocapsid (N) protein in 1441 COVID-19 convalescent patients within 15 months longitudinal nationwide mu...
Alzheimer’s disease (AD)-associated neurodegeneration is triggered by different fragments of amyloid beta (Aβ). Among them, Aβ (25-35) fragment plays a critical role in the development of neurodegeneration—it reduces synaptic integrity by disruption of excitatory/inhibitory ratio across networks and alters the growth factors synthesis. Thus, in thi...
Noise is a wide-spread stress factor in modern life produced by urbanization, traffic, and an industrialized environment. Noise stress causes dysfunction and neurotransmission impairment in the central nervous system, as well as changes in hormone levels. In this study, we have examined the level of α-Tocopherol (α-T) and malondialdehyde (MDA) in p...
Background
Autism Spectrum Disorder (ASD) is characterized by persistent deficits in social communication and interaction and restricted-repetitive patterns of behavior, interests, or activities. ASD is generally associated with chronic inflammatory states, which are linked to immune system dysfunction and/or hyperactivation. The latter might be co...
Using the rat Alzheimer's disease (AD)-like model we have analyzed the hippocampal short-term potentiation, levels of monoamines, and morphological changes in the hippocampal and cortical neurons after the administration of proteoglycans of embryonic origin (PEG). Results showed that the levels of monoamines in the target AD brain structures were f...
The search for new therapeutics for the treatment of Alzheimer’s disease (AD) is still in progress. Aberrant pathways of synaptic transmission in basal forebrain cholinergic neural circuits are thought to be associated with the progression of AD. However, the effect of amyloid-beta (Aβ) on short-term plasticity (STP) of cholinergic circuits in the...
Aim
Necrotizing enterocolitis (NEC) is still a disease with high morbidity and mortality. The aim of the study was to analyse retrospectively whether the introduction of a multi‐modal three‐component enteral medication regimen resulted in a change in morbidity and mortality in neonates NEC.
Methods
When diagnosis of NEC was established, the follow...
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 expressio...
The contribution of the local angiotensin receptor system to neuroinflammation, impaired neurogenesis, and amyloid beta (Aβ) accumulation in Alzheimer’s disease (AD) and in hypertension is consistent with the remarkable neuroprotection provided by angiotensin receptor blockers (ARBs) independent of their blood pressure-lowering effect. Considering...
Autism spectrum disorders (ASD) are common heterogeneous neurodevelopmental disorders with typical triad of symptoms: impaired social interaction, language and communication abnormalities and stereotypical behavior. Despite extensive research, the etiology and pathogenesis of ASD remain largely unclear. The lack of solid knowledge on the mechanisms...
INTRODUCTION: One of the critical components in development of neurodegenerative disorders like disease (AD) is impairment in neurotransmitter system. In this study we tried to reveal the real impact of monoaminergic system (the role of norepinephrine, dopamine and serotonin). Interventions directed to preventing the disturbance in neurotransmitter...
Introduction:
We have analyzed the alterations in the brain monoaminergic system using the rat model of AD-like pathology. In addition, we have investigated potential neuroprotective effects of the hypothalamic proline-rich polypeptide (PRP-1).
Methods:
Histochemical staining, HPLC, chemiluminescent and bioluminescence assays.
Results:
The lev...
The real impact of reactive oxygen species, antioxidant enzymes, mitochondrial dysfunction and chronic inflammation on the development of autism spectrum disorders (ASD) remains unclear, and even controversial. In this study we compared the plasma levels of antioxidant enzymes and their cofactors, markers of oxidative damage, and the respiratory bu...
Locus coeruleus-noradrenergic system dysfunction is known to contribute to the progression of Alzheimer’s disease (AD). Besides a variety of reports showing the involvement of norepinephrine and its receptor systems in cognition, amyloid β (Aβ) metabolism, neuroinflammation, and neurogenesis, little is known about the contribution of the specific r...
Abstract
The latest achievements in the fields of machine learning and artificial neural networks have made the recording of Local Filed Potentials (LFP) more valuable method for the study of brain activity. Along with the improvement of analysis of gained data, the modern approaches in signal amplification schemes brought progress in this method....
Autism spectrum disorders (ASD) are common heterogeneous neurodevelopmental disorders with typical triad of symptoms: impaired social interaction, language and communication abnormalities, and stereotypical behavior. Despite extensive research, the etiology and pathogenesis of ASD remain largely unclear. The lack of solid knowledge on the mechanism...
Abstract
Controllable weak magnetic fields are widely used in biology and medicine to study the influence of these fields on biological objects. To simulate geomagnetic storms and to study the influence of those storms on biological objects we have designed and created a computerized Helmholtz coil system. In this paper, the design, characteristics...
The studies based on the amyloid model of Alzheimer’s disease discovered some possible mechanisms involved in the pathogenesis of neurodegeneration. A new complex of proteoglycans of embryonic genesis created by Mkrtchyan L., as well as a hypothalamic proline-rich peptide created by Galoyan A., were used as possible therapeutic approaches that can...
On a model of neurodegeneration induced by neurotoxic peptide fragment (25–35) of β-amyloid (Aβ), we studied changes in the content of neurotrophins: insulin-like growth factor 1 (IGF-1) and nerve growth factor (NGF) in different brain areas, as well as the thymus, liver, and blood serum of rats under the influence of hypothalamic proline-rich pept...
It is recognized that the main trigger of Alzheimer disease related neurodegeneration is β-amyloid peptide, which subsequently generates different metabolic disorders in neuron and finally leads to neuronal death. Several biologically active products were tested as neuroprotectors, but only few of them demonstrated any efficiency. Proline-rich poly...
One of the crucial events in the pathogenesis of neurodegenerative disorders linked with dementia-like Alzheimer's Disease (AD) is the disturbance in neurotransmission based on progressive deficit of neuromediators that is manifested by marked decrease in cognitive behavior, loss of memory and inability to learn as a result of impairment in synapti...
The development of effective and safe drugs for a growing Alzheimer disease population is an increasing need at present. Both experimental and clinical evidence support a beneficial effect of proline-rich polypeptides in a number of neurodegenerative diseases, including Alzheimer disease. Experimental data have shown that proline-rich polypeptides...
Projects
Project (1)
The purpose of the current research program is to develop a brain-machine interface by registration and study of Local Field Potentials (LFP). During the project realization the methods of registration of LFP and the data analyzing algorithms will be developed.
The recording of the electrical activity of a brain is an irreplaceable method for studying the behavior of neural populations and mathematical or physical patterns underlying this behavior.
The LFP is a compound signal, which is the result of various electrical currents generated in the extracellular space in a brain. Mainly LFP points out synchronized synaptic activity of large group of neurons [5]. The advantage of LFP recording is high spatial resolution and relatively uniform conductivity of selected areas. An additional reason of interest in LFPs is that they provide stable signal for a longer period than multiunit spiking activity, and therefore, are useful for long‐term chronic experiments and for clinical applications such as Brain Machine Interfaces (BMI) [6]. However, as LFP captures a multitude of neural processes, the extraction of essential features is among the main problems of Computational Neuroscience.
The quality of LFP analysis is very important for various tasks starting from relatively simple Brain-Computer interfaces for limb prostheses regulation to more complex cognitive neural implants to treat neurodegenerative disorders.
Our project aims to record and analyze brain activity with further development of analysis tools via brain stimulation. This will lead to more detailed and deep understanding of brain cognitive functions, which will help in the development of Brain Machine Interfaces.
