Anti-SARS-CoV-2 Activity of a Polyphenolic Complex from Maackia amurensis.

We studied the ability of the polyphenolic complex from Maackia amurensis, the active substance of Maksar, to inhibit the cytopathogenic effect induced by the SARS-CoV-2 and to reduce the concentration of viral RNA in infected Vero E6 cells. Polyphenolic complex showed significant anti-SARS-CoV-2 activity and effectively inhibited viral replication by direct action on viral particles and the early stage of viral infection.

[Hepatoprotective properties of isoflavonoids from roots of Maackia amurensis on experimental carbon tetrachloride-induced hepatic damage].

Hepatoprotective properties of ethanol extract from the roots of Maackia amurensis Ruper et Maxim have been studied on the model of toxic hepatitis induced by carbon tetrachloride damage. It is established that the extract contains daidzein, 7-O-gentobiosides of isoflavonoids genistein, formononetin, pseudobabtige-nin, and 5-O-methylgenistein, and 3-O-gentobiosides of pterocarpans (6aR, 11aR)-maakiain and (6aR, 11aR)-medicarpin. The administration of extract facilitates the restoration of antioxidant protection enzymes activity and reduced glutathione level, decreases the formation of toxic peroxidation products, produces normalizing impact on liver phospholipid pattern, and improves the erythrocyte tolerance to hemolytic agents. The action of isoflavonoids from Maackia amurensis in restoration of metabolic pathways of the liver and removal of toxic stress was more effective as compared to that of the reference hepatoprotector legalon.

Effects of histochrom and emoxypin on biophysical properties of electroexitable cells.

Comparative investigation of effects of antioxidant agents histochrom and emoxypin on biophysical characteristics of isolated neurons from shell Lymnaea stagnalis under normal conditions and during oxidative stress was performed. Differently directed effects of these compounds on resting potential and transmembrane ion currents of neural cells under normal conditions were detected. Histochrom provides hyperpolarizing and emoxypin--depolarizing effect on neuronal membrane potential. Under conditions of oxidative stress both products possess antioxidant action. Obtained data allows coming closer to understanding of cellular-molecular mechanisms of protective action of compounds.

[Effects of Maackia amurensis extract on the lipid spectrum and lipid peroxidation in erythrocyte membranes of ovariectomized rats].

Ovariectomy in rats induces the activation of lipid peroxidation processes, reduces total lipid content, and decreases the accumulation of lysophospholipids in erythrocyte membranes. The administration of Maackia amurensis extract (200 mg/kg, p.o., during 14 days) reduces the level of lipid peroxidation, prevents a decrease in the total lipid content, normalizes the proportion of lipids and proteins, and eliminates the accumulation of lysophospholipids in erythrocyte membranes in ovariectomized rats.

[Pathophysiological mechanisms of hemorrhagic stroke and the ways of differential therapy].

The changes developing in the perifocal area of hematoma and perspectives of antioxidant and chelate therapy were studied on the model of experimental hemorrhagic stroke and in clinical conditions. Microcirculatory, ischemic and inflammation disturbances with a certain time sequence were found in the perifocal areas. These changes, along with hypostasis and oxidative stress, form the pathobiochemical cascade of changes in hemorrhagic stroke and are potential therapeutic targets. Administering of an antioxidant and chelate drug histochrome reduces the intensity of changes in the perifocal area in the experimental conditions. In clinical conditions, it accelerates the dynamics of brain and meningeal symptoms regression and improves the blood rheological properties.

[Hepatoprotector properties of polyphenolic complexes from wood and cell culture of Maackia amurensis].

Polyphenolic complexes (PPCs) extracted from core wood and cell culture of Maackia amurensis decrease the acute toxicity of tetrachloromethane, suppress the necrosis of hepatocytes and the cellular infiltration in liver parenchyma, prevent the development of fatty and protein dystrophy in the liver, normalize the activity of aminotransferases and gamma-glutamyltransferase in the blood, restore the protein and lipid content, and stimulate the conjugation of bilirubin. The therapeutic effect was more pronounced for the PPC obtained from the cell culture. The hepatoprotector effect of the PPCs is due to the presence of isoflavonoids, including daidzein, retusin, genistein, afromosin, formononetin, orobol, tektorigenin, maakiain, and medicarpin. Ther PPC from the cell culture of Maackia amurensis does not affect the blood cholesterol level, which is probably explained by the absence of mono- and dimeric stilbenes in this cell culture.

[An influence of histochrome on the dynamics of neurological disorders and MRT-picture in experimental hemorrhagic stroke].

Presented are the results of the use of histochrome in animals with experimental hemorrhagic stroke. An influence of the compound on cerebral edema and the dynamics of hemoglobulin converting as well as a role of MRT in diagnostic of experimental hemorrhagic stroke in different periods of the disease are discussed.

[Antioxidant activity of the hepatoprotector maxar in experimental diabetes]. / Antioksidantnoe deistvie gepatoprotektora maksara pri éksperimental'nom diabete.

Maxar, a hepatoprotector of plant origin containing polyphenols, exhibits an antioxidant effect in animals with alloxane-induced diabetes. The administration of maxar reduces the intensity of lipid peroxidation (LPO) and normalizes the level of LPO products (diene conjugates, malonic dialdehyde, Schiff bases) in liver. The drug produces regulation of the protective antioxidant system primarily by increasing the level of endogenous antioxidants via activation of the glutathione-dependent enzymatic mechanisms and detoxication of lipid hydroperoxide radicals.

Effect of Maksar on antioxidant system in rats with type IIa alimentary hyperlipoproteinemia.

The development of type IIa alimentary hyperlipoproteinemia in rats was accompanied by changes in activity of glutathione-dependent enzymes, exhaustion of the reserves of antioxidant vitamins in the liver and blood, and intensification of lipid peroxidation. The hepatoprotective preparation Maksar obtained from far-eastern plants Maachia amurensis and containing natural biological antioxidants normalized blood lipid composition, corrected liver lipidosis, and improved the antioxidant defense system.

Halenaquinol, a natural cardioactive pentacyclic hydroquinone, interacts with sulfhydryls on rat brain Na(+),K(+)-ATPase.

Halenaquinol inhibited the partial reactions of ATP hydrolysis by rat brain cortex Na(+),K(+)-ATPase, such as [3H]ATP binding to the enzyme, Na(+)-dependent front-door phosphorylation from [gamma-(33)P]ATP, and also Na(+)- and K(+)-dependent E(1)<-->E(2) conformational transitions of the enzyme. Halenaquinol abolished the positive cooperativity between the Na(+)- and K(+)-binding sites on the enzyme. ATP and sulfhydryl-containing reagents (cysteine and dithiothreitol) protected the Na(+),K(+)-ATPase against inhibition. Halenaquinol can react with additional vital groups in the enzyme after blockage of certain sulfhydryl groups with 5,5'-dithio-bis-nitrobenzoic acid. Halenaquinol inhibited [3H]ouabain binding to Na(+),K(+)-ATPase under phosphorylating and non-phosphorylating conditions. Binding of fluorescein 5'-isothiocyanate to Na(+),K(+)-ATPase and intensity of fluorescence of enzyme tryptophanyl residues were decreased by halenaquinol. We suggest that interaction of halenaquinol with the essential sulfhydryls in/or near the ATP-binding site of Na(+),K(+)-ATPase resulted in a change of protein conformation and subsequent alteration of overall and partial enzymatic reactions.

[Therapeutic effect of hepatoprotectors in experimental Reye syndrome]. / [Gepatoprotektory okazyvaiut lechebnoe deistvie pri éksperimental'nom sindrome Reie]

Maxar and legalon--hepatoprotectors containing polyphenols--exhibit a therapeutic effect with respect to the experimental Reye's syndrome induced in rats by intraperitoneal injections of 4-pentenoic acid. Maxar restores the activity of enzymes of the hepatic origin, normalizes the content of bilirubin, glucose, phenols, and malonic aldehyde in the blood serum, stimulates the production of ketone bodies and ammonia detoxication, and improves the histologic structures of liver and cortex. Legalon also decreases the structural-metabolic disorders accompanying the Reye's syndrome, but to as lower ewxtent.

[Histochrome, a new antioxidant, in the treatment of ocular diseases]. / Novyi bioantioksidant "Gistokhrom" v klinike glaznykh boleznei.

The efficacy of a new bioantioxidant histochrome is studied in 92 patients (98 eyes). The drug was injected subconjunctivally or parabulbarly in a dose of 0.5 ml 0.02% solution daily, 7-10 injections per course. The clinical effect of histochrome is determined by the localization, duration, and extent of the process. The drug was the most effective in the treatment of intraocular hemorrhages which occurred no more than 7 days before. Electroretinography demonstrated pronounced retinoprotective properties of the drug which improved the electrophysiological parameters in degenerative processes in the retina and optic nerve. Hence, histochrome is characterized by hemoresorption, retinoprotective, and antioxidant properties and is recommended for the treatment of ocular diseases involving metabolic disorders in the retina, vascular membrane, and cornea.

Inhibition of membrane transport ATPases by halenaquinol, a natural cardioactive pentacyclic hydroquinone from the sponge Petrosia seriata.

Halenaquinol, a natural cardioactive pentacyclic hydroquinone from the sponge Petrosia seriata, was found to be a powerful inhibitor of the rat brainstem and of the rat brain cortex Na+, K(+)-ATPases and the rabbit muscle sarcoplasmic reticulum Ca(2+)-ATPase with I50 values of 7.0 x 10(-7), 1.3 x 10(-6) and 2.5 x 10(-6) M, respectively. Halenaquinol also inhibited K(+)-phosphatase activity of the rat brain cortex Na+, K(+)-ATPase with an I50 value of 3 x 10(-6) M. Ouabain-insensitive Mg(2+)-ATPase activity of the microsomal fraction of the rat brain cortex was weakly inhibited by halenaquinol. Inhibition was irreversible, dose- and time-dependent. Naphthohydroquinone fragment in structures of halenaquinol, related natural and model compounds was very important for an inhibiting effect.

[Pharmacokinetics and clinical efficacy of histochrome in patients with acute myocardial infarction]. / Farmakokinetika i klinicheskaia éffektivnost' gistokhroma u bol'nykh ostrym infarktom miokarda.

The effect of the antioxidant histochrom on the size of the myocardial infarction and activity of the cardioselective enzyme creatine phosphokinase was studied in 45 patients with acute myocardial infarction during thrombolytic therapy. Changes in blood plasma histochrom concentration were studied in 7 patients with myocardial infarction after a single intravenous infusion of 100 mg of the drug. The pharmacokinetic parameters of the drug are shown. The use of histochrom in thrombolytic treatment of acute myocardial infarction lead to limitation of the necrotic zone and increase of myocardial contractility, and results in a more favorable course of the processes of left-ventricular remodeling.

[The antioxidant histochrome: its effect on lipid peroxidation and the blood rheological properties in patients with unstable stenocardia]. / Antioksidant gistokhrom: vliianie na perekisnoe okislenie lipidov i reologicheskie svoistva krovi u bol'nykh bestabil'noi stenokardiei.

Lipid peroxidation and blood rheology were assessed in the course of treatment with antioxidant histochrome and placebo of 66 unstable angina pectoris (UAP) patients. Histochrome has a high antioxidant activity and effectively inhibits accumulation of lipoperoxides in plasma and red cells of UAP patients, promotes stabilization of blood cell function and structures, reduces red cell and platelet aggregation.