Chronic Cerebral Ischaemia Forms New Cholinergic Mechanisms of Learning and Memory

The purpose of this research was a comparative analysis of cholinergic synaptic organization following learning and memory in normal and chronic cerebral ischaemic rats in the Morris water maze model. Choline acetyltransferase and protein content were determined in subpopulations of presynapses of “light” and “heavy” synaptosomal fractions of the cortex and the hippocampus, and the cholinergic projective and intrinsic systems of the brain structures were taken into consideration. We found a strong involvement of cholinergic systems, both projective and intrinsic, in all forms of cognition. Each form of cognition had an individual cholinergic molecular profile and the cholinergic synaptic compositions in the ischaemic rat brains differed significantly from normal ones. Our data demonstrated that under ischaemic conditions, instead of damaged connections new key synaptic relationships, which were stable against pathological influences and able to restore damaged cognitive functions, arose. The plasticity of neurochemical links in the individual organization of certain types of cognition gave a new input into brain pathology and can be used in the future for alternative corrections of vascular and other degenerative dementias

Phenols and GABAA receptors: from structure and molecular mechanisms action to neuropsychiatric sequelae

γ-Aminobutyric acid type A receptors (GABAARs) are members of the pentameric ligand-gated ion channel (pLGIC) family, which are widespread throughout the invertebrate and vertebrate central nervous system. GABAARs are engaged in short-term changes of the neuronal concentrations of chloride (Cl−) and bicarbonate (HCO3−) ions by their passive permeability through the ion channel pore. GABAARs are regulated by various structurally diverse phenolic substances ranging from simple phenols to complex polyphenols. The wide chemical and structural variability of phenols suggest similar and different binding sites on GABAARs, allowing them to manifest themselves as activators, inhibitors, or allosteric ligands of GABAAR function. Interest in phenols is associated with their great potential for GABAAR modulation, but also with their subsequent negative or positive role in neurological and psychiatric disorders. This review focuses on the GABAergic deficit hypotheses during neurological and psychiatric disorders induced by various phenols. We summarize the structure–activity relationship of general phenol groups concerning their differential roles in the manifestation of neuropsychiatric symptoms. We describe and analyze the role of GABAAR subunits in manifesting various neuropathologies and the molecular mechanisms underlying their modulation by phenols. Finally, we discuss how phenol drugs can modulate GABAAR activity via desensitization and resensitization. We also demonstrate a novel pharmacological approach to treat neuropsychiatric disorders via regulation of receptor phosphorylation/dephosphorylation

Transcriptomic changes triggered by ouabain in rat cerebellum granule cells: Role of α3- and α1-Na+,K+-ATPase-mediated signaling

It was shown previously that inhibition of the ubiquitous α1 isoform of Na+,K+-ATPase by ouabain sharply affects gene expression profile via elevation of intracellular [Na+]i/[K+]i ratio. Unlike other cells, neurons are abundant in the α3 isoform of Na+,K+-ATPase, whose affinity in rodents to ouabain is 104-fold higher compared to the α1 isoform. With these sharp differences in mind, we compared transcriptomic changes in rat cerebellum granule cells triggered by inhibition of α1- and α3-Na+,K+-ATPase isoforms. Inhibition of α1- and α3-Na+,K+-ATPase isoforms by 1 mM ouabain resulted in dissipation of transmembrane Na+ and K+ gradients and differential expression of 994 transcripts, whereas selective inhibition of α3-Na+,K+-ATPase isoform by 100 nM ouabain affected expression of 144 transcripts without any impact on the [Na+]i/[K+]i ratio. The list of genes whose expression was affected by 1 mM ouabain by more than 2-fold was abundant in intermediates of intracellular signaling and transcription regulators, including augmented content of Npas4, Fos, Junb, Atf3, and Klf4 mRNAs, whose upregulated expression was demonstrated in neurons subjected to electrical and glutamatergic stimulation. The role [Na+]i/[K+]i-mediated signaling in transcriptomic changes involved in memory formation and storage should be examined further

Gender differences in the pharmacological actions of pegylated glucagon-Like peptide-1 on endothelial progenitor cells and angiogenic precursor cells in a combination of metabolic disorders and lung emphysema

In clinical practice, the metabolic syndrome (MetS) is often associated with chronic obstructive pulmonary disease (COPD). Although gender differences in MetS are well documented, little is known about sex-specific differences in the pathogenesis of COPD, especially when combined with MetS. Consequently, it is not clear whether the same treatment regime has comparable efficacy in men and women diagnosed with MetS and COPD. In the present study, using sodium glutamate, lipopolysaccharide, and cigarette smoke extract, we simulated lipid metabolism disorders, obesity, hyperglycemia, and pulmonary emphysema (comorbidity) in male and female C57BL/6 mice. We assessed the gender-specific impact of lipid metabolism disorders and pulmonary emphysema on angiogenic precursor cells (endothelial progenitor cells (EPC), pericytes, vascular smooth muscle cells, cells of the lumen of the nascent vessel), as well as the biological effects of pegylated glucagon-like peptide 1 (pegGLP-1) in this experimental paradigm. Simulation of MetS/COPD comorbidity caused an accumulation of EPC (CD45−CD31+CD34+), pericytes, and vascular smooth muscle cells in the lungs of female mice. In contrast, the number of cells involved in the angiogenesis decreased in the lungs of male animals. PegGLP-1 had a positive effect on lipids and area under the curve (AUC), obesity, and prevented the development of pulmonary emphysema. The severity of these effects was stronger in males than in females. Furthermore, PegGLP-1 stimulated regeneration of pulmonary endothelium. At the same time, PegGLP-1 administration caused a mobilization of EPC (CD45−CD31+CD34+) into the bloodstream in females and migration of precursors of angiogenesis and vascular smooth muscle cells to the lungs in male animals. Gender differences in stimulatory action of pegGLP-1 on CD31+ endothelial lung cells in vitro were not observed. Based on these findings, we postulated that the cellular mechanism of in vivo regeneration of lung epithelium was at least partly gender-specific. Thus, we concluded that a pegGLP-1-based treatment regime for metabolic disorder and COPD should be further developed primarily for male patients

Стресс-индуцированная дисфункция тромбоцитов у крыс с фолат-зависимой гипергомоцистеинемией

A rat model of experimental hyperhomocysteinemia (HHC) caused by chronic folic acid deficiency was used to study the impact of swimming stress on the values of agonist-induced platelet aggregation and ATP release. At week 8 of HHC development, platelet aggregability and ATP levels in response to test inductors (ADP, thrombin, and collagen) moderately increased. After stress, the rate of platelet aggregation showed a more increase in rats with HHC; however, the increment was less pronounced than in the control group. The similar changes was observed in ATP, the release of which from dense platelet granules decreased in the experimental animals exposed to stress changes as compared to the controls. The experimental findings suggest that the stress potentiates platelet dysfunction in HHC. На модели экспериментальной гипергомоцистеинемии (ГГЦ) у крыс, вызванной хроническим дефицитом в организме фолиевой кислоты, изучалось влияние плавательного стресса на показатели агонист-индуцированной агрегации тромбоцитов и реакцию высвобождения из них АТФ. Показано, что на восьмой неделе развития ГГЦ агре-гационная способность тромбоцитов, как и уровень АТФ на все исследованные индукторы (АДФ, тромбин, коллаген), умеренно повышались. После стрессовой нагрузки интенсивность агрегации тромбоцитов у крыс с ГГЦ еще более возрастала, однако прирост ее был менее выраженным, чем в контрольной группе. Аналогичная динамика зарегистрирована со стороны АТФ, выброс которого из плотных тромбоцитарных гранул опытных животных, подвергнутых стрессу, уменьшался по сравнению с контролем. Результаты экспериментов свидетельствуют о потенцирующем влиянии стресса на дисфункцию тромбоцитов при ГГЦ.

НАУЧНАЯ ШКОЛА АКАДЕМИКА В.И. ШВЕЦА: БИОНАНОФАРМАЦЕВТИЧЕСКИЕ ТЕХНОЛОГИИ ИННОВАЦИОННЫХ ЛЕКАРСТВЕННЫХ ПРЕПАРАТОВ НАПРАВЛЕННОГО ДЕЙСТВИЯ И ПОДГОТОВКА КАДРОВ

The results of many years of scientific research in the field of physico-chemical biology and its most important direction - lipidology, conducted by the leading scientific school under the leadership of Academician RAS Vitaly I. Shvets, are reported. On the creation of synthetic, biotechnological methods for obtaining lipids, with the possibility of their practical use by designing on this basis effective diagnostic and medicinal products and application in practical medicine. The further development and use of methods of bionanotechnology for the development of modern medicines for directed action on the basis of increasing the effectiveness of classical drugs by their incorporation into nanocontainers is described. It is reported on the development of technologies for obtaining nanoscale forms of drugs, the study of their pharmacological properties and use in medical practice. Information is provided on the preparation of liposomal antitumor, hepatoprotective, anti-tuberculosis, cardiac preparations based on the proposed echnologies, the study of properties and the use for therapeutic purposes. The technologies for obtaining and conducting biological studies of nanoforms based on copolymers of lactic and glycolic acids of antineoplastic, anti-inflammatory, antibacterial and a number of other drugs have been developed: It has been shown that the use of nanosized drugs can lead to a significant increase in the pharmacological effect due to various factors. It was noted that during the construction of the drug for the treatment of Parkinson's disease, the contents of liposomes loaded with dopamine pass through the blood-brain barrier almost 100 times better than individual dopamine molecules. Finding a substance in nanoparticles reduces its toxicity primarily due to the effect of "passive targeting". The prolonged action of medicinal substances enclosed in nanoparticles is discussed, due to their gradual release. It is noted that the targeted delivery of nanoparticles makes it possible to increase the effectiveness of the drugs by an order of magnitude. It is reported on the drug-delivery technology in the field of oncology and the use of the method of selective delivery of cytostatics to tumor tissues using the receptor-mediated endocytosis. Biological and pharmacological studies based on nanopoporous silicon on the creation of liposomal drugs for the treatment of cancer, cardiological pathologies, tuberculosis are carried out. Data on the work of the scientific and educational center for training specialists in the field of biotechnology and pharmacy are given.Сообщается о результатах многолетней научно-исследовательской работы в области физико-химической биологии и важнейшего ее направления - липидологии, проводимой ведущей научной школой под руководством академика РАН В.И. Швеца по созданию синтетических, биотехнологических методов получения липидов, с возможностью практического их использования путем конструирования на этой основе эффективных диагностических и лекарственных препаратов и применения в медицине. Описано дальнейшее развитие и использование методов бионанотехнологии для создания современных лекарственных средств направленного действия на базе повышения эффективности классических препаратов включением их в наноконтейнеры. Сообщается о разработке технологий получения наноразменых форм лекарственных препаратов, исследовании их фармакологических свойств и использовании в медицинской практике. Приводятся сведения о получении на основе предложенных технологий, изучении свойств и применении в лечебных целях липосомальных противоопухолевых, гепатопротекторных, противотуберкулезных, кардиологических препаратов. Созданы технологии получения и проведены биологические исследования наноформ на основе сополимеров молочной и гликолевой кислот противоопухолевых, противоинсультных, антибактериальных и ряда других препаратов. Показано, что использование наноразмерных лекарств может приводить к значительному увеличению фармакологического эффекта за счет разных факторов. Так, отмечается, что в процессе конструирования препарата для лечения болезни Паркинсона содержимое липосом, нагруженных дофамином, проходит через гематоэнцефалический барьер практически в 100 раз лучше, чем отдельные молекулы дофамина. Нахождение субстанции в наночастицах снижает ее токсичность прежде всего вследствие эффекта «пассивного нацеливания». Обсуждается пролонгированное действие лекарственных субстанций, заключенных в наночастицы, за счет их постепенного высвобождения. Отмечено, что адресная доставка наночастиц позволяет на порядок увеличить эффективность действия лекарств. Сообщается о технологии направленного транспорта лекарственных препаратов (drug-delivery) в области онкологии и об использовании метода избирательной доставки цитостатиков в опухолевые ткани с использованием рецептор-опосредованного эндоцитоза. Проводятся биологические и фармакологические исследования на основе нанопопористого кремния по созданию липосомальных лекарственных препаратов для лечения рака, кардиологических патологий, туберкулеза. Приведены данные о работе научно-образовательного центра по подготовке специалистов в области биотехнологии и фармации

Intricacies of GABA_A Receptor Function: The Critical Role of the β3 Subunit in Norm and Pathology

Neuronal intracellular chloride ([Cl−]i) is a key determinant in γ-aminobutyric acid type A (GABA)ergic signaling. γ-Aminobutyric acid type A receptors (GABAARs) mediate both inhibitory and excitatory neurotransmission, as the passive fluxes of Cl− and HCO3− via pores can be reversed by changes in the transmembrane concentration gradient of Cl−. The cation–chloride co-transporters (CCCs) are the primary systems for maintaining [Cl−]i homeostasis. However, despite extensive electrophysiological data obtained in vitro that are supported by a wide range of molecular biological studies on the expression patterns and properties of CCCs, the presence of ontogenetic changes in [Cl−]i—along with the consequent shift in GABA reversal potential—remain a subject of debate. Recent studies showed that the β3 subunit possesses properties of the P-type ATPase that participates in the ATP-consuming movement of Cl− via the receptor. Moreover, row studies have demonstrated that the β3 subunit is a key player in GABAAR performance and in the appearance of serious neurological disorders. In this review, we discuss the properties and driving forces of CCCs and Cl−, HCO3−ATPase in the maintenance of [Cl−]i homeostasis after changes in upcoming GABAAR function. Moreover, we discuss the contribution of the β3 subunit in the manifestation of epilepsy, autism, and other syndromes

Funktsional'naya aktivnost' trombotsitov pri sakharnom diabete 2 tipa v protsesse lecheniya preparatami sul'fonilmocheviny

Актуальность Специфические сосудистые осложнения, или микроангиопатий, развиваются при СД 2 типа наряду с ускоренным прогрессированием атеросклероза, что сопровождается повышенным риском тромбозов, нарушения кровообращения и внезапной смерти. Основные причины этих острых ситуаций при СД 2 типа ? это ослабление эндотелийзависимой релаксации, изменение сократимости гладкомышечной сосудистой стенки и повышение функциональной активности тромбоцитов. Цель Сравнить влияние на окислительный стресс и функциональную активность тромбоцитов двух производных сульфонилмочевины: глибенкламида и гликлазида. Материалы и методы В 1-ю группу (8 чел.) вошли больные, получавшие на момент включения в исследование диабетон в суточной дозе от 120 до 240 мг. Во 2-ю группу (8 человек) были включены больные, получавшие на момент начала исследования Манинил??5 в суточной дозе 10-15 мг. Определяли уровень HbA1c, агрегацию тромбоцитов, липиды сыворотки, цитоплазматический Са, активность процессов перекисного окисления липидов (ПОЛ) определяли спектрофотометрическим методом, исследовали синтез тромбоцитарного сосудосуживающего фактора ? тромбоксана. Результаты Достижение компенсации углеводного обмена сопровождалось достоверным снижением HbAlc. При этом отмечалась и тенденция к снижению гипер- и дислипидемии. При достижении компенсации углеводного обмена получено достоверное снижение базального и индуцированного МДА. Функциональная активность тробоцитов также менялась, что проявилось достоверным снижением амплитуды агрегации тромбоцитов на тромбин и коллаген в обеих группах, тенденцией к снижению агрегации на АДФ в 1-й группе по сравнению с достоверным снижением агрегации на АДФ во 2-й группе больных. Уровень цитоплазматического кальция, как базального, так и стимулированного тромбином и АДФ, также достоверно снижался в обеих группах, равно как и концентрация тромбоксана В2. Выводы Проведенный сравнительный анализ не выявил преимуществ гликлазида перед глибенкламидом в отношении коррекции реоваскулярных изменений, развивающихся на фоне окислительного стресса. Отсутствие компенсации углеводного обмена вызывает прогрессирование гемореологических нарушений, являющихся основной причиной формирования диабетических ангиопатий, вне зависимости от вида получаемой сахароснижающей терапии

Zinc Inhibits the GABA_AR/ATPase during Postnatal Rat Development: The Role of Cysteine Residue

Zinc ions (Zn2+) are concentrated in various brain regions and can act as a neuromodulator, targeting a wide spectrum of postsynaptic receptors and enzymes. Zn2+ inhibits the GABAARs, and its potency is profoundly affected by the subunit composition and neuronal developmental stage. Although the extracellular amino acid residues of the receptor’s hetero-oligomeric structure are preferred for Zn2+ binding, there are intracellular sites that, in principle, could coordinate its potency. However, their role in modulating the receptor function during postembryonic development remains unclear. The GABAAR possesses an intracellular ATPase that enables the energy-dependent anion transport via a pore. Here, we propose a mechanistic and molecular basis for the inhibition of intracellular GABAAR/ATPase function by Zn2+ in neonatal and adult rats. The enzymes within the scope of GABAAR performance as Cl−ATPase and then as Cl−, HCO3−ATPase form during the first week of postnatal rat development. In addition, we have shown that the Cl−ATPase form belongs to the β1 subunit, whereas the β3 subunit preferably possesses the Cl−, HCO3−ATPase activity. We demonstrated that a Zn2+ with variable efficacy inhibits the GABAAR as well as the ATPase activities of immature or mature neurons. Using fluorescence recording in the cortical synaptoneurosomes (SNs), we showed a competitive association between Zn2+ and NEM in parallel changes both in the ATPase activity and the GABAAR-mediated Cl− and HCO3− fluxes. Finally, by site-directed mutagenesis, we identified in the M3 domain of β subunits the cysteine residue (C313) that is essential for the manifestation of Zn2+ potency