Publications by authors named "Alexander M Zakharenko"

15 Publications

  • Page 1 of 1

Telomerase and telomeres in aging theory and chronographic aging theory (Review).

Mol Med Rep 2020 Sep 25;22(3):1679-1694. Epub 2020 Jun 25.

Laboratory of Toxicology, Medical School, University of Crete, 71003 Heraklion, Greece.

The current review focuses on the connection of telomerase and telomeres with aging. In this review, we describe the changes in telomerase and telomere length (TEL) during development, their role in carcinogenesis processes, and the consequences of reduced telomerase activity. More specifically, the connection of TEL in peripheral blood cells with the development of aging‑associated diseases is discussed. The review provides systematic data on the role of telomerase in mitochondria, the biology of telomeres in stem cells, as well as the consequences of the forced expression of telomerase (telomerization) in human cells. Additionally, it presents the effects of chronic stress exposure on telomerase activity, the effect of TEL on fertility, and the effect of nutraceutical supplements on TEL. Finally, a comparative review of the chronographic theory of aging, presented by Olovnikov is provided based on currently available scientific research on telomere, telomerase activity, and the nature of aging by multicellular organisms.
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http://dx.doi.org/10.3892/mmr.2020.11274DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7411297PMC
September 2020

Behavioral impacts of a mixture of six pesticides on rats.

Sci Total Environ 2020 Jul 15;727:138491. Epub 2020 Apr 15.

Far Eastern Federal University, Vladivostok, Russian Federation; Pacific Geographical Institute FEB RAS, Vladivostok, Russian Federation. Electronic address:

Pesticides can potentially contribute to the development of numerous neurodegenerative diseases. This study evaluates the effects of a six-pesticide mixture at doses around the no-observed-adverse-effectlevels (0 × NOAEL, control) and 0.25, 1 and 5 × NOAEL on behavior of Wistar rats. After 3, 6 and 12 months, rats were observed for neurobehavioral changes using the techniques of elevated plus maze and universal problemchamber, and the experiment was conducted thrice. The 3-month exposure revealed a decrease in the cognitive ability at the dose of 5 × NOAEL, and a dose-dependent research activity and anxiety. The 6-month exposurerevealed non-monotonic effects on the cognitive ability, with a decrease by 0.25 and 5 × NOAEL, as well as non-monotonic effects on anxiety, withan increase by 0.25 and 1 × NOAEL. A decrease was also observed in research activity at 5 × NOAEL. However, the 12-month exposure resulted to an increase in cognitive ability by 0.25 × NOAEL and in anxiety by 1 × NOAEL, as well as to a dose-dependent research activity. Repeating the trial showed that the cognitive ability increased from one trial to another, while the researching activity decreased and the anxiety increased by 0× NOAEL. In the groups exposed to pesticides mixture, the trends were different, showing that the exposure to pesticides combined with repeated trials, also influence the response of the animals. The resultsdemonstrate the occurrence of several dose-dependent behavioral responses, with negative effects occurring at doses that are considered safe. This study provides novel insights about time-dependent mixtures biology, and an important perspective to consider when conducting risk assessments.
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http://dx.doi.org/10.1016/j.scitotenv.2020.138491DOI Listing
July 2020

Light-Emitting Nanophotonic Designs Enabled by Ultrafast Laser Processing of Halide Perovskites.

Small 2020 May 20;16(19):e2000410. Epub 2020 Apr 20.

ITMO University, St. Petersburg, 197101, Russia.

Nanophotonics based on resonant nanostructures and metasurfaces made of halide perovskites have become a prospective direction for efficient light manipulation at the subwavelength scale in advanced photonic designs. One of the main challenges in this field is the lack of large-scale low-cost technique for subwavelength perovskite structures fabrication preserving highly efficient luminescence. Here, unique properties of halide perovskites addressed to their extremely low thermal conductivity (lower than that of silica glass) and high defect tolerance to apply projection femtosecond laser lithography for nanofabrication with precise spatial control in all three dimensions preserving the material luminescence efficiency are employed. Namely, with CH NH PbI perovskite highly ordered nanoholes and nanostripes of width as small as 250 nm, metasurfaces with periods less than 400 nm, and nanowire lasers as thin as 500 nm, corresponding to the state-of-the-art in multistage expensive lithographical methods are created. Remarkable performance of the developed approach allows to demonstrate a number of advanced optical applications, including morphology-controlled photoluminescence yield, structural coloring, optical- information encryption, and lasing.
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http://dx.doi.org/10.1002/smll.202000410DOI Listing
May 2020

Toxicity assessment of particulate matter emitted from different types of vehicles on marine microalgae.

Environ Res 2019 12 30;179(Pt A):108785. Epub 2019 Sep 30.

Far Eastern Federal University, Vladivostok, 690950, Russian Federation; Pacific Geographical Institute FEB RAS, Vladivostok, 690014, Russian Federation.

Air pollution caused by vehicle emissions remains a serious environmental threat in urban areas. Sedimentation of atmospheric aerosols, surface wash, drainage water, and urbane wastewater can bring vehicle particle emissions into the aquatic environment. However, the level of toxicity and mode of toxic action for this kind of particles are not fully understood. Here we explored the aquatic toxic effects of particulate matter emitted from different types of vehicles on marine microalgae Porphyridium purpureum and Heterosigma akashiwo. We used flow cytometry to evaluate growth rate inhibition, changes in the level of esterase activity, changes in membrane potential and size changes of microalgae cells under the influence of particulate matter emitted by motorcycles, cars and specialized vehicles with different types of engines and powered by different types of fuel. Both microalgae species were highly influenced by the particles emitted by diesel-powered vehicles. These particle samples had the highest impact on survival, esterase activity, and membrane potential of microalgae and caused the most significant increase in microalgae cell size compared to the particles produced by gasoline-powered vehicles. The results of the algae-bioassay strongly correlate with the data of laser granulometry analyses, which indicate that the most toxic samples had a significantly higher percentage of particles in the size range less than 1 μm. Visual observation with an optical microscope showed intensive agglomeration of the particles emitted by diesel-powered vehicles with microalgae cells. Moreover, within the scope of this research, we did not observe the direct influence of metal content in the particles to the level of their aquatic toxicity, and we can conclude that physical damage is the most probable mechanism of toxicity for vehicle emitted particles.
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http://dx.doi.org/10.1016/j.envres.2019.108785DOI Listing
December 2019

Monitoring of environmental persistent organic pollutants in hair samples collected from wild terrestrial mammals of Primorsky Krai, Russia.

Environ Sci Pollut Res Int 2019 Mar 21;26(8):7640-7650. Epub 2019 Jan 21.

Pacific Geographical Institute FEB RAS, Vladivostok, Russia.

Persistent organic pollutants (POPs) constitute a wide range of chemicals. Their release into the environment has raised great concern due to their potentially harmful impact in humans and wildlife species. The aim of this current study was to detect selected POPs in hair samples of wild terrestrial mammals from Primorsky Krai, Russia, so as to assess potential environmental exposure. The tested wild species were leopard cat, musk deer, wolf, amur hedgehog, and raccoon dog. The targeted organochlorines were hexachlorobenzene (HCB) and DDTs (opDDE, ppDDE, and opDDD), polychlorinated biphenyl (PCB) congeners (28, 52, 101, 118, 138, 153, and 180), and polycyclic aromatic hydrocarbons (PAHs) (acenaphylene (ACEN), fluorene (FLU), anthracene (ANTH) phenathrene (PHEN), and pyrene (PYR)). The detection of POPs was conducted in hair samples by a one-step hair extraction method, by using a headspace solid-phase microextraction technique (HS-SPME) and analyzed then by GC-MS. The majority of the wild animal hair samples were found positive in all tested pollutants. More specifically, the percentage of positive hair samples for HCB was 93.3% and for DDTs, PCBs, and PAHs, 20.0 to 100.0%, 6.7 to 100.0%, and 75.0 to 100.0%, respectively. DDT, PCB, and PAH detection ranged from 1.26 to 52.06 pg mg, 0.73 to 31.34 pg mg, and 2.59 to 35.00 pg mg, respectively. The highest mean concentration levels of all tested pollutants were found for musk deer (PCBs 12.41 pg mg, DDTs 21.87 pg mg, PAHs 22.12 pg mg) compared to the other wild species. To the best of our knowledge, this is the first study that provides results regarding contamination in different terrestrial mammals by POP exposure. The use of hair as a matrix is proven to be an effective tool for nondestructive biological monitoring of POP contamination in terrestrial ecosystems.
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http://dx.doi.org/10.1007/s11356-019-04171-9DOI Listing
March 2019

Enhancement of Antioxidant Mechanisms and Reduction of Oxidative Stress in Chickens after the Administration of Drinking Water Enriched with Polyphenolic Powder from Olive Mill Waste Waters.

Oxid Med Cell Longev 2017 24;2017:8273160. Epub 2017 Aug 24.

Department of Biochemistry and Biotechnology, University of Thessaly, Viopolis, 41500 Larissa, Greece.

The aim of the study was to examine the effects of a polyphenolic powder from olive mill wastewater (OMWW) administered through drinking water, on chickens' redox status. Thus, 75 chickens were divided into three groups. Group A was given just drinking water, while groups B and C were given drinking water containing 20 and 50 g/ml of polyphenols, respectively, for 45 days. The antioxidant effects of the polyphenolic powder were assessed by measuring oxidative stress biomarkers in blood after 25 and 45 days of treatment. These markers were total antioxidant capacity (TAC), protein carbonyls (CARB), thiobarbituric acid reactive species (TBARS) and superoxide dismutase activity (SOD) in plasma, and glutathione (GSH) and catalase activity in erythrocytes. The results showed that CARB and TBARS were decreased significantly in groups B and C, and SOD decreased in group B compared to that in group A. TAC was increased significantly in group C and GSH was increased in group B, while catalase activity was increased in groups B and C compared to that in group A. In conclusion, this is the first study showing that supplementation of chickens with polyphenols from OMWW through drinking water enhanced their antioxidant mechanisms and reduced oxidative stress-induced damage.
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http://dx.doi.org/10.1155/2017/8273160DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5613686PMC
July 2018

CYP polymorphisms and pathological conditions related to chronic exposure to organochlorine pesticides.

Toxicol Rep 2017 26;4:335-341. Epub 2017 May 26.

Research Group of Clinical Pharmacology and Pharmacogenomics, Faculty of Pharmacy, School of Health Sciences, National and Kapodistrian University of Athens, Greece.

The association between genetic variations in the cytochrome P450 (CYP) family genes and pathological conditions related to long-term exposure to organochlorine compounds (OCs) deserves further elucidation. OCs are persistent organic pollutants with bioaccumulative and lipophilic characteristics. They can act as endocrine disruptors and perturb cellular mechanisms. Prolonged exposure to OCs has been associated with different pathological manifestations. CYP genes are responsible for transcribing enzymes essential in xenobiotic metabolism. Therefore, polymorphisms in these genetic sequences a. alter the metabolic pathways, b. induce false cellular responses, and c. may provoke pathological conditions. The main aim of this review is to define the interaction between parameters a, b and c at a mechanistic/molecular level, with references in clinical cases.
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http://dx.doi.org/10.1016/j.toxrep.2017.05.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5615117PMC
May 2017

Basophil mediated pro-allergic inflammation in vehicle-emitted particles exposure.

Environ Res 2017 Jan 8;152:308-314. Epub 2016 Nov 8.

Far Eastern Federal University, Engineering School, Scientific Educational Centre of Nanotechnology, 690950, Vladivostok, Russia. Electronic address:

Despite of the fact that engine manufacturers develop a new technology to reduce exhaust emissions, insufficient attention given to particulate emissions. However, diesel exhaust particles are a major source of air-borne pollution, contain vast amount of polycyclic aromatic hydrocarbons (PAHs) and may have deleterious effects on the immune system, resulting in the induction and enhancement of pro-allergic processes. In the current study, vehicle emitted particles (VEP) from 2 different types of cars (diesel - D and gasoline - G) and locomotive (L) were collected. Overall, 129 four-week-old, male SPF-class Kunming mice were subcutaneously instilled with either low dose 100, 250 or high dose, 500mg/kg VEP and 15 mice were assigned as control group. The systemic toxicity was evaluated and alterations in the percentages of the CD3, CD4, CD8, CD16, CD25 expressing cells, basophils, eosinophils and neutrophils were determined. Basophil percentages were inversely associated with the PAH content of the VEPs, however basophil sensitization was more important than cell count in VEP exposure. Thus, the effects of VEP-PAHs emerge with the activation of basophils in an allergen independent fashion. Despite the increased percentage of CD4+ T cells, a sharp decrease in basophil counts at 500mg/kg of VEP indicates a decreased inhibitory effect of CD16+ monocytes on the proliferation of CD4+ T cell and suppressed polarization into a Th2 phenotype. Therefore, although the restrictions for vehicles emissions differ between countries, follow up studies and strict regulations are needed.
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http://dx.doi.org/10.1016/j.envres.2016.10.031DOI Listing
January 2017

Fucoidanases.

Glycobiology 2016 Jan 7;26(1):3-12. Epub 2015 Sep 7.

G. B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences, Vladivostok, 159, Prospect 100-let, Vladivostoku 690022, Russia.

In recent years, the research of fucoidans has steadily increased. The interest in these substances is due to their various biological activities. Despite a wide range of biological activity and the lack of oral toxicity, fucoidans remain relatively unexploited as a source of medicines because of their heterogeneity. Enzymes that degrade polyanionic polysaccharides are widely used for establishing their structures and structure-activity relationships. Sometimes, to obtain preparations of polysaccharides with standard characteristics, for example, medicines and food supplements, enzymatic treatment can be also applied. Only a few sources of enzymes with fucoidanase activity have been described, and only a few studies regarding the isolation and characterization of fucoidanases have been performed. The data on the specificity of fucoidanases: the type of cleaved glycoside bond, the relation between catalytic activity and the degree of substrate sulfation are scarce. The review summarizes achievements in the research of fucoidanases, mechanisms of enzymatic degradation of fucoidans, as well as of structures of sulfated fucooligosaccharides obtained under the action of fucoidanases.
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http://dx.doi.org/10.1093/glycob/cwv072DOI Listing
January 2016

Phytoliths in taxonomy of phylogenetic domains of plants.

Biomed Res Int 2014 27;2014:648326. Epub 2014 Aug 27.

Laboratory of Molecular Biology, Blagoveshchensk State Pedagogical University, 104 Lenina Street, Blagoveshchensk 675000, Russia.

We discuss, from the aspect of phylogeny, the interrelationships of the phytolith types in plants from the main taxonomical groups (algae, lichens, horsetails, gymnosperms, and floral plants) with homologues of known proteins of biomineralization. Phytolith morphotypes in various phylogenetic plant domains have different shapes. We found that, in ancient types of plants (algae, horsetails, and gymnosperms), there are fewer different phytolith morphotypes compared to more modern plants (floral plants). The phytolith morphotypes in primitive plants are generally larger than the morphotypes in more highly organized plants. We found that the irregular ruminate and irregular smooth morphotypes are the two most frequently encountered phytolith morphotypes in the tested plants (from algae to floral plants). These two morphotypes probably have a universal role. Silacidins, silicon transporters, silicateins, silaffins, and silicase homologues are often found in the major taxonomic groups of plants. Red algae had the smallest number of homologues of the biomineralization proteins (70-80), Monocotyledonous: 142, Coniferous: 166, Mosses: 227, and Dicotyledones: 336.
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http://dx.doi.org/10.1155/2014/648326DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4163427PMC
June 2015

Meroterpenoids from the alga-derived fungi Penicillium thomii Maire and Penicillium lividum Westling.

J Nat Prod 2014 Jun 22;77(6):1390-5. Epub 2014 May 22.

G.B. Elyakov Pacific Institute of Bioorganic Chemistry, Far-Eastern Branch of the Russian Academy of Sciences , Prospect 100-let Vladivostoku 159, Vladivostok 690022, Russian Federation.

Ten new austalide meroterpenoids (1-10) were isolated from the alga-derived fungi Penicillium thomii KMM 4645 and Penicillium lividum KMM 4663. Their structures were elucidated by extensive spectroscopic analysis and by comparison with related known compounds. The absolute configurations of some of the metabolites were assigned by the modified Mosher's method and CD data. Compounds 1, 2, 8, and 9 were able to inhibit AP-1-dependent transcriptional activity in JB6 Cl41 cell lines at noncytotoxic concentrations. Austalides 1-5, 8, and 9 exhibited significant inhibitory activity against endo-1,3-β-D-glucanase from a crystalline stalk of the marine mollusk Pseudocardium sachalinensis.
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http://dx.doi.org/10.1021/np500151bDOI Listing
June 2014

Hydrolysis of fucoidan by fucoidanase isolated from the marine bacterium, Formosa algae.

Mar Drugs 2013 Jul 11;11(7):2413-30. Epub 2013 Jul 11.

Elyakov Pacific Institute of Bioorganic Chemistry, Far Eastern Branch of the Russian Academy of Sciences, Prospect 100 Let Vladivostok 159, Vladivostok, 690022, Russia.

Intracellular fucoidanase was isolated from the marine bacterium, Formosa algae strain KMM 3553. The first appearance of fucoidan enzymatic hydrolysis products in a cell-free extract was detected after 4 h of bacterial growth, and maximal fucoidanase activity was observed after 12 h of growth. The fucoidanase displayed maximal activity in a wide range of pH values, from 6.5 to 9.1. The presence of Mg2+, Ca2+ and Ba2+ cations strongly activated the enzyme; however, Cu2+ and Zn2+ cations had inhibitory effects on the enzymatic activity. The enzymatic activity of fucoidanase was considerably reduced after prolonged (about 60 min) incubation of the enzyme solution at 45 °C. The fucoidanase catalyzed the hydrolysis of fucoidans from Fucus evanescens and Fucus vesiculosus, but not from Saccharina cichorioides. The fucoidanase also did not hydrolyze carrageenan. Desulfated fucoidan from F. evanescens was hydrolysed very weakly in contrast to deacetylated fucoidan, which was hydrolysed more actively compared to the native fucoidan from F. evanescens. Analysis of the structure of the enzymatic products showed that the marine bacteria, F. algae, synthesized an α-l-fucanase with an endo-type action that is specific for 1→4-bonds in a polysaccharide molecule built up of alternating three- and four-linked α-l-fucopyranose residues sulfated mainly at position 2.
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http://dx.doi.org/10.3390/md11072413DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3736431PMC
July 2013

Enzymatic and molecular characterization of an endo-1,3-β-d-glucanase from the crystalline styles of the mussel Perna viridis.

Carbohydr Res 2011 Feb 13;346(2):243-52. Epub 2010 Nov 13.

Pacific Institute of Bioorganic Chemistry FEB RAS, Vladivostok, 690022, pr.100 let Vladivostoku 159, Russia.

The retaining endo-1,3-β-d-glucanase (EC 3.2.1.39) was isolated from the crystalline styles of the commercially available Vietnamese edible mussel Perna viridis. It catalyzes hydrolysis of β-1,3-bonds in glucans and enables to catalyze a transglycosylation reaction. Resources of mass-spectrometry for analysis of enzymatic products were studied. cDNA sequence of endo-1,3-β-d-glucanase was determined by RT-PCR in conjunction with the rapid amplification of cDNA ends (RACE) methods. The cDNA of 1380bp contains an open reading frame of 1332bp encoding a mature protein of 328 amino acids. On basis of amino acid sequence analysis endo-1,3-β-d-glucanase was classified as a glycoside hydrolase of family 16.
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http://dx.doi.org/10.1016/j.carres.2010.11.008DOI Listing
February 2011

Isorhizochalin: a minor unprecedented bipolar sphingolipid of stereodivergent biogenesis from the Rhizochalina incrustata.

Lipids 2009 Dec 30;44(12):1155-62. Epub 2009 Oct 30.

Laboratory of MaNaPro Chemistry, Pacific Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 690022 Vladivostok, Russia.

Isorhizochalin (1) was isolated as its peracetate from the EtOH extract of the sponge Rhizochalina incrustata. Its structure and absolute stereochemistry were elucidated as (2S,3R,26R,27R)-2,27-diamino-3-O-beta-D: -galactopyranosyl-oxy-26-hydroxyoctacosan-18-one by extensive NMR, MS studies, chemical transformations, including micromolar-scale Baeyer-Villiger oxidation, and by analysis of CD spectra of isorhizochalinin perbenzoate (2b). Isorhizochalin is an unprecedented C-2 epimer of rhizochalin having an erythro configuration at the glycosylated 2-amino-3-alkanol alpha-terminus in contrast with a canonical threo configuration for other representatives of this structural group. Probable biogenesis of 1 is discussed in the context of known sphingolipid biosynthesis beginning with condensation of alanine with a fatty acyl CoA thioester. The aglycone, isorhizochalinin (2a), shows cytotoxicity against human leukemia HL-60 and THP-1 cells with IC(50) values of 2.90 and 2.20 microM, respectively.
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http://dx.doi.org/10.1007/s11745-009-3360-0DOI Listing
December 2009

Rhizochalins C and D from the sponge Rhizochalina incrustata. A rare threo-sphingolipid and a facile method for determination of the carbonyl position in alpha,omega-bifunctionalized ketosphingolipids.

J Nat Prod 2007 Dec 6;70(12):1991-8. Epub 2007 Dec 6.

Laboratory of MaNaPro Chemistry, Pacific Institute of Bioorganic Chemistry of the Russian Academy of Sciences, 690022, Vladivostok-22, Russian Federation.

Rhizochalins C and D ( 1, 2), new representatives of two-headed glycosphingolipids, were isolated from the sponge Rhizochalina incrustata. Rhizochalin D is an unexpected C 29 homologue of the canonical C 28 dimeric sphingolipid structures. Their structures including absolute configurations were established using spectroscopic data, micromolar-scale Baeyer-Villiger oxidation, and LCMS interpretation of the products. Application of the latter method leads to a revision of the structure of oceanapiside and placement of the keto group at C-18 rather than C-11.
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http://dx.doi.org/10.1021/np0704811DOI Listing
December 2007