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The anti-inflammatory effects of noopept (dipeptide analog of piracetam) upon a single intraperitoneal (i.p.) administration at doses of 1, 5, and 10 mg/kg in comparison to the reference drug diclofenac (10 mg/kg, i.p.) have been studied on a model of acute exudative inflammation induced by carrageenan in outbred rats and concanavalin A (Con A) in CBA mice. The level of cytokines was studied on the lipopolysaccharide (LPS) model (single administration, 100 mg/kg, i.p.) with 5-day administration of noopept at a dose of 5 mg/kg (i.p., before endotoxin injection) in C57BL/6 mice. The administration of noopept led to a significant suppression of the inflammatory response to both carrageenan and Con A. The administration of Con A caused a 16-fold increase in the level of IL-6 interleukin in the blood serum of mice as compared to control. Noopept (5 mg/kg) reduced the level of IL-6 by a factor of 1.8 in the inflammatory response to Con A. The administration of LPS led to pronounced increase in the levels ofpro-inflammatory IL-6 and TNF-alpha in the blood serum of test mice as compared to intact animals. The course administration of noopept (5 mg/kg) significantly decreased the level of IL-6 and reduced by half the level of TNF-alpha.

Effects of the antiasthenic drug ladasten [N-(2-adamantyl)-N-(para-bromophenyl)amine] on the profile of cytokines, behavior, and indexes of immunity organs was studied on zoosocial stress model in depressed C57BL/6 male mice. The anxious depression state in male mice was formed by repeated agonistic interactions according to the sensory contact model. Ladasten (30 mg/kg, i.p.) and reference drug imipramine (10 mg/kg, i.p.) were administered either once after 3-day stressor interaction or for 5 days after 10-day interaction. The concentration of cytokines in blood serum was determined by flow cytometry method. The behavioral changes were studied using an actometer and the elevated plus-maze test. The parameters were studied 24 h after last drug injection. Different stages of depression were manifested by behavioral impairments, increased concentration of pro-inflammatory cytokines IL-6, IL-17, and IL-4, and decreased indexes of immunity organs. Ladasten induced (more significantly than imipramine) a decrease in the level of pro-inflammatory cytokines IL-6, IL-17 and IL-4, removed behavioral changes, and restored indexes of immunity organs. Thus, the antiasthenic drug ladasten limits development of the anxious depressive state and suppresses the level ofproinflammatory cytokines IL-6, IL-17 and IL-4. These findings suggest that ladasten is a possible candidate drug for adjuvant therapy of depressive disorders.

Afobazole and M-11, its major metabolite were detected in placental and embryonic rat tissues after single peroral administration to pregnant female rats at a dose of 100 mg/kg. The anxiolytic drug and its metabolite are also detected in rat milk and body of the breast-fed infant rat pups after 4 days of daily administration (200 mg/kg, per os) to lactating female rats.

Preclinical safety investigations of newly synthesized dipeptide compound GB-115 (amide N-phenylhexanoyl-glycyl-L-tryptophan), an antagonist of cholecystokinin receptors, were performed. No animals were lost after GB-115 acute oral administration at a maximum dose of 6000 mg/kg in mice and at 3500 mg/kg in rats. GB-115 administered per os during 6 months in rabbits and rats (both males and females) at the doses of 0.1 and 10 mg/kg induced no irreversible pathological changes in organs and systems studied. The tested dipeptide exhibited no allergenic, immunotoxic and mutagenic activity, and did not affect generative function and the antenatal and postnatal development of progeny. GB-115 at a dose of 10 mg/kg produced suppression of the inflammatory reaction to concanavalin A.

Experiments of mice and rats showed the ability of afobazole (1, 10, and 100 mg/kg, p.o.) upon single, 5-day combined, and 5-day preliminary administration to prevent or significantly decrease the clastogenic effects of the prooxidant agent dioxidine (100 and 300 mg/kg, i.p.) and the clastogenic and teratogenic effects of the alkylating agent cyclophosphamide (20 mg/kg, i.p.).

The chromosome aberration assay in the bone marrow cells of C57BL/6 mice was used to study the cytogenetic activity of ribavirin (10, 50, 100, 200, and 400 mg/kg, p.o.) alone and in combinations with verapamil (0.25, 2.5, 5, and 10 mg/kg, p.o.). It was established that ribavirin was cytogenetically active upon single administration in a dose of 200 and 400 mg/kg, and it was also active in a dose of 50 and 100 mg/kg when administered for 5 days in combination with verapamil in a dose of 5 or 10 mg/kg and 2.5, 5, or 10 mg/kg, respectively. These results indicate that verapamil and ribavirin exhibit comutagen action.

Non-narcotic analgetics sodium diclofenac, indomethacin, naproxen, nimesulid, ketorolac, and celebrex (cytochrome P-450(2)c substrates) produce more pronounced and prolonged analgesic effect in pubertate female rats than in males. This can be related to the slower elimination of drugs from the female organism. The liver of females is characterized by a lower content of cytochrome P-450 and by less pronounced activity of amidopyrine-N-, indomethacin-O-, and naproxen-O-demethylase activity. No sex-related differences in pharmacodynamics were observed for meloxicam, and ethoricoxib, benzofurocaine, and amison, and acetylsalicylic acid, which are the substrates predominantly for CYP3A.

Effect of the new potential antiparkinsonian drug hemantane (N-(adamant-2-yl)hexamethyleneimine hydrochloride) on the generative function and gonad morphology was studied in a group of male and female mongrel rats. The generative function was studied after peroral drug administration in a dose of 10 mg/kg (ED50) and 50 mg/kg (5 ED50): males were treated over a 60-day period of spermatogenesis, while females received the drug in the same doses over 15 days (three estrous cycles). The gonad morphology was studied after a 6-month treatment of experimental animals with hemantane in the same doses. It was established that the administration hemantane in indicated doses did not influence the generative function and gonad morphology in male and female rats.

Himantane introduced via a gastric tube to pregnant rats in a dose of 10, 30, 50, and 100 mg/kg produced a dose-dependent embryotoxic and teratogenic action. An analysis of the experimental results and published data suggests that the embryotoxicity of himantane can be related to its general toxic action upon the organism of pregnant female rats.

The method of fluorometric analysis for DNA unity (FADU) was used to study the genotoxic effects of cyclophosphamide in rats. The dose dependence and time variation of mutagenicity manifestations in various organs and tissues of the experimental animals was studied. It was established that FADU results agree with the data obtained by conventional methods of cytogenetics. The results confirm the expediency of using FADU for the preclinical investigations of drugs.

The chromosome aberration assay in the bone marrow cells of C57BL/6 mice showed that melanin pigment (MP) in a dose range from 0.01 to 10 mg/kg does not influence the clastogenic effect of dioxidine (200 mg/kg, i.p.), while reducing the clastogenic effect of cyclophosphamide (20 mg/kg, i.p.) by a factor of 1.5-4 in various treatment regimes depending on the mutagen injection time.

The effect of an endotoxin from Sh. Boydii on the biotransformation of amidopyrine and acetanilide, the activity of microsomal monooxygenases, hemoxygenase, and xanthine oxidase, the lipid peroxidation (LPO) intensity, the phospholipid spectrum, and the solubilization of microsomal membrane components was studied by intraperitoneal injections (2.5 mg/kg) in rats. It was found that the endotoxin inhibits the reactions of C- and N-acetanilide hydroxylation, N-amidopyrine demethylation, acetanilide hydrolysis at the amide bond, conjugation of aminophenol metabolites with glucuronic acid and sulfate, and 4-aminoantipyrine binding to acetate. The endotoxin effect reached maximum 24 h after injection and was observed for 96 h. The inhibition of metabolism of the test preparations is related to a decrease in the content of cytochrome P-450 and in the activity of 1A2, its 2B, 2C, 3A, and 2E1 isoforms. This is obviously caused by activated LPO and enhanced nitric oxide synthesis, as evidenced by a tenfold increase in the content of NO metabolites (nitrites and nitrates) in the blood of test animals. In clinical practice, it is necessary to take into account the possibility of a significant biotransformation of drugs in the acute period of bacterial infection, which may lead to changes in the pharmacological effect and toxicity of some drugs.

The influence of lacidipine (0.1-10 mg/kg, intragastric) on the clastogenic effect of dioxidine (100 and 200 mg/kg, i.p.) under conditions of their single and repeated (five-fold, 24-h interval) administration was studied by the chromosome aberration assay in the metaphase bone marrow cells of BALB/c and C57BL/6 male mice. It was found that single (5 or 10 mg/kg) and repeated (10 mg/kg) introduction of lacidipine enhances the clastogenic effect of dioxidine in both genotypes. At the same time, a single treatment of C57BL/6 mice with 0.1 and 1 mg/kg of lacidipine sometimes significantly reduced the clastogenic effect of dioxidine (200 mg/kg). Thus, lacidipine exhibits a comutagen effect in vivo when administered at large doses (5 and 10 mg/kg) but not at small doses, where the drug sometimes acted as antimutagen in C57BL/6 mice.

The chromosome aberration assay in the bone marrow cells of C57B1/6 mice showed that the new 2-mercaptobenzimidazole derivative afobazole(1-100 mg/kg) prevented manifestations of the clastogenic effects of dioxidine (100 mg/kg, i.p.) over a period of 24 h and reduced by 44-75% the cytogenetic effect of dioxidine (300 mg/kg, i.p.). The same doses of afobazole produced a statistically significant decrease in the cyclophosphamide (20 mg/kg, i.p.) damage over a period of 24 h. Afobazole showed no inherent mutagen activity and did not potentiate the effects of mutagens studied.

The genotoxic effect of dioxidine (300, 100, 30, and 10 mg/kg, i.p.) on the liver cells of outbred male rats was studied by fluorometric analysis of DNA unwinding (FADU) using the cell DNA samples taken from animals sacrificed 1, 6, 18, and 24 h after drug introduction. At a dose of 10 mg/kg, dioxidine produced no statistically significant increase in the amount of DNA damage relative to control. Increase in the dioxidine dose to 30 mg/kg resulted in a significant DNA damage 1 h after drug administration, while a dose of 100 or 300 mg/kg reliably caused damage at all times of exposure.

The levels of autoantibodies against DNA in blood serum and severity of the disease were evaluated prior to, during, and after 8-week treatment of patients suffering from lupus erythematosus systemicus (LES) with prednisolonum (daily dose of 5-60 mg/kg, 15 patient) and with prednisolonum in combination with cyclophosphane (CP) (a total dose of 2-4 mg/kg per os. 15 patients), or bemithyl doses of 500-750 mg/day per os (15 patients) or bemithyl in combination with CP (the same doses, 16 patients). It was shown that introduction of bemithyl into LES treatment schedule significantly lowered the level of autoantibodies against DNA evaluated in immunoassay and reduced LES severity assessed using standard SLEDAI-1 and ECLAM scales.

The method of chromosome aberration count in the bone marrow cells of C57B1/6 mice was used to study the influence of aspartame on the cytogenetic effects of dioxydin and cyclophosphan. Aspartame (0.4-40 mg/kg) was found to possess antimutagenic properties in relation to the listed mutagens. The discovered antimutagenic activity of aspartame was manifested more when it was injected for 5 days before the administration of a mutagen, whereas in joint administration of aspartame with the mutagens, the substitute for sugar did not change the clastogenic effect of dioxydin and cyclophosphan.

The method of chromosome aberration count in the bone marrow cells of male BALB/c and C57Bl/6 mice was used to study the influence of intraperitoneal injection of verapamil in doses of 0.1-10 mg/kg and its administration into the stomach in doses of 2.5-10 mg/kg on the clastogenic effect of cyclophosphamide (10 mg/kg intraperitoneally) in a single and repeated (5 times at intervals of 24 h) administration. In repeated administration in all the doses used, verapamil significantly intensified the mutagenic activity of cyclophosphamide in C57Bl/6 mice and in doses 10 mg/kg in BALB/c mice. A single intraperitoneal verapamil injection (0.1-0.4 mg/kg) caused a statistically increase in the clastogenic effect of cyclophosphan in mice of both strains. The same effect was encountered in intraperitoneal injection (2.5 mg/kg) and administration into the stomach (5 mg/kg) of the calcium antagonist in BALB/c mice. Thus, the effect of verapamil on cyclophosphamide clastogenic activity depends on the dose, method, and schedule of administration of the calcium antagonist.

Cytogenetic study conducted after a single intraperitoneal injection of cyclophosphane in doses of 10, 20, and 40 mg/kg showed in 1.5-2-month-old male mice that the level of bone marrow cells damaged by the mutagen was significantly higher in NZW animals than in C57Bl/6 animals. The ability to produce active oxygen forms in response to addition of opsonized zymosan and phorbol myristate acetate was also higher in bone marrow suspensions of NZW mice. The higher sensitivity of NZW animals to pro-oxidant and clastogenic effects may be related to the genetically determined decrease of antioxidant protection in NZW animals.

The article deals with the results characterizing the state of Russian and foreign elaborations in the study of genotoxic effects of drugs and immunobiological agents. Particular attention is placed on general problems of strategy and tactics in the study of mutagenicity of drugs the solution of which is insufficiently substantiated or insufficiently discussed in the literature. The perspective problems of research into the field of genotoxicity of drugs are discussed.

The method of chromosome aberration scoring in the bone marrow cells of C57BL/6 mice was used to study the influence of apo-carotene (AC) on the clastogenic effect of intraperitoneal injections of the following two mutagens: cyclophosphamide (CP) in a dose of 30 mg/kg and dioxidine (DN) in a dose of 300 mg/kg. AC was given per os as a food dye E160L (20% oil suspension) in doses of 0.5, 5, and 50 mg/kg (0.1, 1.0 and 10 mg/kg, respectively, on conversion to pure apo-carotene). The experiment was conducted in three variants: in simultaneous injection of the compounds for 24 h, injection of the mutagens for 24 h in 5-day treatment of the animals with AC, and in combined 5-day administration of AC and mutagens and killing of the animals 6 h after the last administration. In all variants a 10 mg/kg dose of AC reduced the clastogenic effect of CP and DN. Moreover, the clastogenic effect of CP was reduced in pretreatment of the animals with AC in a dose of 1 mg/kg, and that of DN when it was combined with AC in a dose of 0.1 mg/kg for 5 days and in pretreatment of the animals with AC in a dose of 1.0 mg/kg.