[Interaction of rifampicin embedded in phospholipid nanoparticles with blood plasma lipoproteins].

The drug formulations of antituberculous remedy rifampicin in nanoparticles less than 30 nm based on soy phosphatidylcholine and sodium oleate was elaborated in Institute of Biomedical Chemistry. The distribution of rifampicin in blood plasma fractions after incubation with this formulation and with free rifampicin was studied. This goal was stimulated by the literature data about activation of macrophages LDL receptors in cases of M. tuberculosis infection. Plasma was incubated 30 min with free rifampicin or rifampicin encapsulated into the nanoformulation followed by ultracentrifugation and subsequent rifampicin determination by HPLC in lipoprotein fractions. In the case of free rifampicin it appeared mainly in the plasma protein fraction and in HDL (41% and 38%, correspondentely). But after incubation of rifampicin in nanoparticles the drug redistribution was observed. Its proportion in these factions decreased 2-3-fold, and it was found mainly in LDL (60% as compared with 21% for free rifampicin). The increased association of rifampicin encapsulated into phospholipid nanoparticles with LDL is considered as facilitating factor for macrophages delivery and thus for antituberculosis efficiency as well.

[Nanoparticles as drug delivery system for antituberculous drugs].

The increase of tuberculosis incidence in last decade stimulated elaboration of both new antituberculous drugs and also searches ofoptimiting delivery systems for existing drugs. It is determined by their side effects and low bioavailability of effective first line drug rifampicin. Various nanosystems for transport of antituberculous drugs are considered on the basis of various polymers, liposomes, lipid nanoparticles, nanoemulsios, nanosuspensions, dendrimers, cyclodextrines. Influence of drug incorporation into nanoparticles, most often for rifampicin, on pharmacokinetics and efficiency in tuberculosis models is discussed. The most of works are devoted to polymer nanoparticles for oral administration where increased circulation time and efficiency were shown. The best results were observed after drug inclusion into solid lipid nanoparticles. The liposomes formulations were investigated mostly for inhalation and injection administrations. Positive results were also observed. Authors underline the viability of incorporation of antituberculous drugs into phospholipid nanoparticles that may increase intestinal absorption and bioavailability. It is confirmed by authors' own data that showed increase of rifampicin efficiency after their incorporation into such nanoparticles.

[Changes of doxorubicin distribution in blood and plasma after its inclusion into nanophospholipd formulation].

The drug composition based on the plant phospholipids and the antitumor drug doxorubicin (particle size <30 nm) was obtained using original technology elaborated in the Institute of Biomedical Chemistry (Russian Academy of Medical Sciences). In in vitro experiments demonstrated decreased drug association with blood cells for this nanophospholipid form as compared with free doxorubicin. This was accompanied by a with corresponding increase in its plasma level ans also by drug redistribution from plasma protein fraction to high density lipoproteins. Significance of these changes for doxorubicin biodistributon and antitumor activity is discussed.

[The increase of bioavailability and anti-inflammatory effect of indomethacin loaded into phospholipid nanoparticles].

The ultrafine formulation on the base of plant phosphatidylcholine and antiinflammatory remedy indomethacin with nanoparticles less than 50 nm was obtained. Drug bioavailability after its peroral administration to rats was more than 2 fold higher as compared with free indomethacin. Increased antiinflammatory activity of indomethacin in phospholipids nanoparticles as compared with its free form was shown in two models of inflammation - adjuvant arthritis in rats and conconavalin A induced edema in mice. The increased bioavailability of indomethacin after administration of its phospholipid formulation allows to decrease a dose for achievement of therapeutic effect, that reduces risks of occurrence of collateral displays.

[Plasma lipoproteins as drug carriers. Effect of phospholipid formulations].

The extensive development of nanotechnologies in the last two decades has brought about new understanding of plasma lipoproteins (LP) as natural drug nanocarriers that escape interaction with immune and reticuloendothelial systems. Drugs bound to LP (especially LDL) can more actively penetrate into cells of many cancer and inflammation tissues with enhanced expression or/and dysregulation of B,E receptors or possibly scavenger SR-BI receptors. Relevant studies are focused on the development of new dosage forms by conjugating lipophilic drugs either with isolated plasma LP or with their model formulations, such as nanoemulsions, mimetics, lipid nanospheres, etc. Some authors include in these particles serum or recombinant apoproteins, peptides, and modified polymer products. As shown recently, protein-free lipid nanoemulsions in plasma take up free apoA and apoE. Complexes with various LP also form after direct administration of lypophilic drugs into blood especially those enclosed in phospholipid formulations, e.g. liposomes. Results of evaluation of some lipophilic dugs (mainly cytostatics, amphotericin B, cyclosporine A, etc.) are discussed. Original data are presented on the influence of phospholipid formulations on the distribution of doxorubicin and indomethacin between LP classes after in vitro incubation in plasma. On the whole, the review illustrates the importance of research on LP and phospholi pid forms as drug nanocarriers to be used to enhance effect of therapy.

[Bioavailability of oral drug formulations and methods for its improvement].

The recent studies in nanotechnology resulted in the development of novel formulations with improved bioavailability. This is especially important for oral administered drugs as the most convenient formulations. The current review deals with the processes occurring at the gastro-intestinal (GI) tract and their influence on the drug form. The increase of bioavailability of the drug may be achieved through designing novel formulations according to the specific drug properties. They include capsules that release pharmaceutical agents at various parts of the GI tract, floating systems that prolong the presence of the drug in the GI tract, dispersed forms with surface-active soluble polymers, micelles that carry poor-soluble drugs inside their non-polar core, agents that facilitate tight junction opening, such as caprate and chitosan, and lipid-based formulations. The own data show the stimulating influence of phospholipid nanoparticles on peroral absorption of drug indomethacin in rats and on passage of transport marker and drugs through Caco-2 cell monolayer in vitro. The review summarizes current understanding of factors that influence the bioavailability of the oral drug forms, currently used models for pharmacokinetic studies, and various approaches to developing novel pharmaceutical forms that increase the bioavailability of the drugs.

[Comatose states: etiopathogenesis, experimental studies, treatment of hepatic coma].

The review presents the modern concepts on biochemical mechanisms of processes, that result in comatose states (CS), with emphasis on the search of new therapeutic approaches. CS of various origin causes severe suppression of brain cells functioning and stable unconsciousness. Numerous reasons of various CS are classified into two main groups: primary brain damages (ischemia, tumor, trauma) and secondary damages originating from system injuries in the body (endocrine, toxic e. c.). The most often primary CS is the hypoxic-ischemic one, as result of corresponding encephalopathy. Its mechanism is the brain cells "energy crisis"--because of decreased blood supply or its deficiency by energy substrates or/and by oxygen. Among secondary CS the substantial place takes hepatic coma as a consequence of hepatic encephalopathy in severe liver diseases--cirrhosis, acute liver failure, sharp intoxication. Its main reason is associated with exess of ammonia entering the brain tissue (it accumulates in blood because of lack of its removing by damaged hepatocytes). Ammonia reacts with glutamate in brain astrocytes and the product of this reaction, glutamine, induced osmotic imbalance, that results in change of form and functions of these important brain cells. It induces, in turn, neurons functions damages, changes in neurotransmission and cerebral blood flow and all these may give rise CS. The most of CS studies are carried out in human. Experimental models ofhepatic CS are reproduced mainly in rats, the most often by surgery methods. Other models included administration of thioacetamide or D-galactosamine, sometimes in combination with lipopolysaccharide. In earlier studies ammonia administration together with liver damages by ligation or by CCl4 was used. The main principles of hepatic coma treatment include the care of encephalopathy, detoxification, and liver treatment. Elaboration of new nanodrugs with increased penetration into tissues and cells, in particular, on the base of phospholipid nanoparticles, may increase substantially the therapeuti efficiency. One of such drug is thought to be a new hepatoprotective preparation phosphogliv--nanoparticles of soy phosphatidylcholine with glycyrrhizic acid. It is supposed, that the further development of phospholipid nanoforms, with minimal particle sizes, may reveal the more action in CS treatment.

[Possibilities for use of phospholipid nanosystem with glycyrrhizic acid ("phosphogliv") for optimization of drugs: doxorubicin and budesonide as examples].

The complexes of phospholipids nanoparticles (as the injection form of newly developed hepatoprotector phosphogliv) with the antitumor drug doxorubicin or with glucocorticoid budesonide have been investigated for their pharmacological activity in comparison with free forms of these drugs. Doxorubicin with phosphogliv revealed more antitumor and antimetastatic activity in C47B 1/6 mice with carcinoma LLC than free doxorubicin. Inhalation of budesonide with phosphogliv in vivo to quinea pigs resulted to more pronounced decrease of antigen or histamin induced bronchospasm, particularly its subacute phase, as compared with traditional powder or suspension budesonide forms. This suggests that the phosphogliv injection forms may be used not only for treatment of liver diseases, but also for delivery of a number of other drugs and consequently for optimization of their efficiency.

[Antirheumatoid activity of methotrexate in phospholipid nanoparticles (Phosphogliv)].

The efficiency of methotrexate use in basic therapy of rheumatoid arthritis is limited because of risk of side effects and fast drug efflux from zone of joints as well. The new stabilized form of methotrexate was elaborated with phospholipid micelles as a carrier. The injective form of the preparation Phosphogliv was used for this purpose. Phosphogliv has recently been developed in the Institute of Biomedical Chemistry (Moscow), as the emulsion of 50 nm phospholipid nanoparticles stabilized by glycyrrhizic acid. The conditions of maximal methotrexate incorporation into the phospholipid nanoparticles were optimised under control of HPLC (60% of total methotrexate was associated with nanoparticles, with remaining drug being in free form in the water phase). Such preparation revealed higher therapeutic efficiency in experimental adjuvant arthritis in rats as compared with free methotrexate. The increase of antirheumatoid activity of the elaborated preparation may also be attributed to the influence of glycyrrhizic acid, possessing both antiinflammatory and immune properties. The possibility of clinical employment of a new methotrexate drug form for rheumatoid arthritis treatment is discussed.

[Membrane proteins and phospholipids as effectors of reverse cholesterol transport].

The review highlights the membrane aspect of cholesterol efflux from cell membranes to high density lipoproteins (HDL), an initial stage of reverse cholesterol transport to liver. Special attention is paid to ABC-A1 transporter and membrane SR-B1 receptor, their properties, putative mechanisms of action and their role in reverse cholesterol transport. Interaction of ABC-AI with plasma free apoA1 is suggested to facilitate the efflux of membrane phospholipids and formation of their complex with apoAI. Then this complex accepts the membrane cholesterol, with lipidation till the full HDL particle is formed. For a number of cells the correlation of cholesterol efflux into HDL with SR-BI expression was shown. The reversible binding of receptor SR-BI with HDL is supposed to influence molecular organization of membrane lipids, that promotes the efflux of cholesterol molecules out of the membrane.

[Hypolipoproteinemia and secondary role of atherosclerosis in the development of ischemic heart disease in patients with polycythemia vera].

Relationship between presence of coronary heart disease (CHD), coronary risk factors (parameters of lipid transport system and hypertension) and disturbances of microcirculation was studied in patients with myeloproliferative blood disease Polycythemia Vera (PV). Probability of tissue (including blood vessel wall) cholesterol accumulation was estimated by measurement of its content in skin surface layers. PV patients (n=55, including 27 patients with CHD) had predominant hypolipoproteinemia with normal proportion of various lipoprotein classes. Absence of substantial increase of skin surface cholesterol content both in patients with and without CHD was considered to be a sign of low probability of the presence of severe atherosclerotic processes. However patients with CHD had substantially more pronounced disturbances of microcirculation. Basing on these data the authors suggest that CHD in PV patients had non-lipoprotein genesis and present discussion of alternative mechanisms of vascular changes.

[Phosphatidylcholine as the basis for artificial pulmonary surfactants: comparison of surface active properties]. / Fosfatidilkholiny kak osnova iskusstvennogo legochnogo surfaktanta: sravnenie poverkhnostno-aktivnykh svoistv.

The Wilhelmy balance was used for in vitro testing of surface active properties of natural phosphatidylcholines (PCs) as possible basis for surfactant replacement therapy. Saturated PC, dipalmitoylphosphatidylcholine (DPPC) and phospholipon (PL) had similar parameters of surface activity: minimal values of equilibrium surface tension (EST) and the longest surface spreading time (SST). Unsaturated egg and soybean PCs also shared similar values of surface activity parameters (EST and SST). Correlation between fatty acid saturation of PCs and EST or SST allows to consider both these parameters as informative ones for surface tension evaluation in the search of components for artificial surfactant. Since parameters of DPPC and PL surface activity are equivalent in their performance, they may be potentially employed for testing instead of DPPC as a possible base for artificial surfactant.

[Relation between resistance to oxidation and cholesterol acceptance of high density lipoproteins in patients with ischemic heart disease]. / Vzaimosviaz' mezhdu okislitel'noi ustoichivost'iu i kholesterin-aktseptornoi sposobnost'iu lipoproteinov vysokoi plotnosti u bol'nykh ishemicheskoi bolezn'iu serdtsa.

Cholesterol (CH) acceptance ability of high density lipoproteins (HDL) was assessed in 43 ischemic heart disease (IHD) patients, including patients with post-infarction cardiosclerosis and class II-III effort angina. CH acceptance ability of HDL was measured as increment of HDL CH after incubation with artificial CH-containing system. Oxidabilities of HDL and total plasma were estimated by quantitation of lipid peroxidation products (hydroperoxides and thiobarbituric acid-reactive substances - TBARS) after incubation with Cu(2+) ions. HDL fraction (after apo B lipoproteins removal) of IHD patients appeared to include 2 times less additive CH compared with donor's HDL despite lower (-12%) HDL CH level. Negative correlation (r =-0.38, p<0.05) existed between formed TBARS in HDL and HDL CH acceptance. In total plasma of IHD patients elevation of both formed TBARS and particularly hydroperoxides was observed. Parallelism between decrease of CH acceptance by HDL, oxidability of HDL and of total plasma testifies on weakness not only of CH-accepting, but also of antioxidant HDL functions in IHD patients.

[The way of evaluation of cholesterol accepting capacity of plasma high density lipoproteins]. / Sposob otsenki kholestrin-aktseptornoi emkosti lipoproteinov vysokoi plotnosti plazmy krovi.

The simple way of quantitative evaluation of high density lipoproteins (HDL) capacity to absorb additive cholesterol quantity is proposed. It allows to evaluate indirectly intensity of the first, rate limiting stage of reverse cholesterol transport its accepting from the cells by means of HDL. The way includes the usage of stable artificial cholesterol donor--cholesterol covered inert polymer particles, which are than more convenient, than cell culture use. The total HDL rough fraction (i.e. serum after apoB lipoproteins removal) was shown to include more than 50% cholesterol in addition to yet presenting amount. But this ability is sharply reduced, or sometimes even is completely absent, in HDL of 63 coronary heart disease (CHD) patients (as compared with 41 healthy donors). This difference of potential cholesterol accepting capacity is revealed even at the same initial HDL concentrations. The negative correlation (r = - 0.32, p < 0.05) between this HDL property (delta HDL cholesterol) and their oxidability in the ions Cu2+ presence was observed. This underlines atherogenic role of HDL oxidability. The treatment of patients by phospholipids (as Lipostabyl) resulted to recovery of HDL cholesterol accepting capacity. The possible mechanisms of junction of this HDL activity with their oxidability are discussed, as well as necessity of evaluation of HDL properties and reverse cholesterol transport for the choice of care strategy of CHD patients.

[Biological effects of the soybean phospholipids]. / Biologicheskaia aktivnost' soevykh fosfolipidov.

Soyabean phospholipids, particularly commercial lecithin, are now widely used as biological active food additives. Mechanisms of their activities are based mainly on their similarity with ow phospholipids of biomembranes and blood lipoproteins. The similarity allows the inclusion of plant phospholipids into these structures and promotes prevention of number of pathological processes. Soybean phospholipids have a wide range of biochemical and physical effects. Lecithin complex is the source of easily accessible linoleic acid, choline and inositol. Lecithin plays a notable role as synergist for antioxidants also. The proven health benefits which can be achieved by taking soybean phospholipids include lipid-lowering; control of blood levels of cholesterol and triglyceride, stabilisation of the membrane functions, supporting the hepatic functions. Structure, some physico-chemical properties and metabolism of phospholipids, and molecular mechanisms of their prophylactic effects are briefly reviewed.

[Erythrocyte cholesterol content in polycythemia vera: relation to ischemic heart disease]. / Soderzhanie kholesterina v éritrotsitakh pri istinnoi politsitemii: sviaz' s ishemicheskoi bolezn'iu serdtsa.

Relative cholesterol content and its distribution between erythrocytes and plasma were studied in 34 patients with polycythemia vera (PV) both with and without concomitant coronary heart disease (CHD). Deformability of erythrocytes, disturbances of microcirculation (blood flow fragmentation, decrease of capillary density) were also assessed. Erythrocytes cholesterol/phospholipids molar ratios (0.68+/-0.03) in patients was lower than normal value (0.8) in spite of decreased cell deformability. This was associated with some increase of peroxidation products. Blood cholesterol distribution between cell and plasma species had some peculiarities caused by high hematocrit: compared with normal value erythrocytes of patients carried relatively larger portion of total blood cholesterol (23.7+/-0.8% and 27-31%, respectively). However in CHD patients these values were significantly lower with correspondent increase of plasma cholesterol quota. This allowed to suggest possible protective role of blood cholesterol redistribution in polycythemia patients, through erythrocytes trafficking of some part of plasma cholesterol.

[Hemorheological and clinical efficiency of a new phospholipid hepatoprotective drug Phosphogliv in patients with psoriatic arthritis]. / Gemoreologicheskaia i klinicheskaia éffektivnost' novogo fosfolipidnogo gepatoprotektornogo preparata "Fosfogliv" u bol'nykh psoriaticheskim artritom.

A new phospholipid drug "Posphogliv" showed earlier good results in the treatment of liver discases. The mechanism of its effect consists in non-specific repair of biomembranes. In the present study it was used for the treatment of in patients with psoriatic arthritis, accompanied by severe damages of blood rheology. The group of patients took Phosphogliv 3 months in the dose of 0.6 g per day. Considerable decrease of erythrocytes aggregability was observed after the treatment. There were no changes in total blood viscosity. The clinical state of patients markedly improved after the treatment. Simultaneous decrease of blood C-reactive protein level suggests weakening of inflammation. The mechanism of these effects may involve direct influence of the phospholipid on erythrocyte membranes and/or with indirect influence through the improvement of liver function. The results show that Phosphogliv inclusion into therapy improved the state of patients with psoriatic arthritis. The results of the present study also indicate principal possibility of broadening of clinical use of this drug. Its positive effects are based on membrane reparative properties of polyunsaturated phosphatidylcholine in combination with anti-inflammatory and immunomodulative effects of its second component, glycyrrhizin acid.

[Characteristics of the lipid transport system in psoriasis]. / Osobennosti lipid-transportnoi sistemy pri psoriaze.

Cholesterol of high density lipoprotein (HDL) subfractions (HDL2 and HDL3), activity of cholesterol ester transport protein (CETP), and standard lipoprotein parameters (cholesterol, triglycerides, HDL cholesterol) were measured in plasma of 192 patients with various psoriasis forms, which included simple "distributed psoriasis", erythrodermic and arthropathic psoriasis. Among psoriatic patients unusually high percent of persons with both hypo- and hyper-cholesterolemia was observed. The same situation was observed with frequency of cases with both low and high plasma HDL cholesterol levels, the distribution being depending from disease severity. In contrast to norm, psoriasis patients had big range not only in HDL2 cholesterol level, but also in HDL3 cholesterol. They also had decreased CETP activity. Data obtained suggest the existence of changes in reverse cholesterol transport system in psoriasis, which may influence skin cell proliferation (via control of cell supply with cholesterol).

[Phosphogliv: mechanism of therapeutic action and clinical efficacy]. / Fosfogliv: mekhanizm deistviia i éffektivnost' primeneniia v klinike.

The review summarizes the results of long term study (from design to clinical trial) of a new hepatoprotective drug Phosphogliv. Some theoretical ground for its creation has been considered with special emphasis on its ingredient properties: soy bean phosphatidylcholine and glycyrrhizinic acid from licorice roots. Experimental and clinical data concerning polyene phosphatidylcholine repairing action on cell membranes as well as antiviral and immunomodulating effects of glycyrrhizinic acid are presented. Their selected combination in Phosphogliv provided its high efficiency in rat hepatitis models. After standard toxicology tests it was allowed to carry out the clinical trials of this preparation in the treatment of liver diseases patients--mainly with acute and chronic viral hepatitis B, C, A and mixed hepatitis B + C (total 203 patients). The inclusion of Phosphogliv into therapy coarse accelerated disappearance of intoxication symptoms and decrease of serum aminotransferase and other hepatic markers. The effect was more pronounced for intravenous drug form.

[New domestic phospholipid preparation "Fosfogliv" as an effective treatment for patients with acute viral hepatitis]. / Novyi otochestvennyi fosfolipidnyi preparat "Fosfogliv" kak effektivnoe sredstvo pri lechenii bol'nykh s ostrymi virusnymi gepatitami.

Patients with acute viral hepatitis B, A and mixed hepatitis B + C were treated in two independent clinics with phosphogliv--a new hepatoprotective drug based on polyunsaturated phosphatidylcholine and glycyrrhizic acid salt. Phosphogliv removed some symptoms of intoxication (nausea, weakness, jaundice, etc.) quicker than basic therapy. Among biochemical hepatitis markers, serum bilirubin level was most responsive to phosphogliv. Standard therapy decreases bilirubin by 30% on the average for 5 days, phosphogliv reduces bilirubin for one more week to half those values observed in control patients. At that point low aminotransferase activities were seen in phosphogliv treated patients. No side effects were seen. The new hepatoprotector phosphogliv which repairs biomembranes represents drugs of new generation compared to phospholipid drug essential.