Anticlastogenic activity of beta-carotene against cyclophosphamide in mice in vivo

beta-Carotene (BC), a natural food colourant and an antioxidant, acts as an antimutagen/anticarcinogen in several test systems. The anticlastogenic activity of BC against cyclophosphamide (CP) was studied in bone marrow cells of mice in vivo. Seven days' oral priming with BC (2.7 and 27 mg/kg b.w.) followed by an acute treatment with cyclophosphamide (25 mg/kg b.w.; i.p.) inhibited clastogenicity. The values of chromosomal aberrations and micronucleated polychromatic erythrocytes were consistently lower than the sum of the expected values of BC and CP given individually. This antagonistic response indicates anticlastogenic activity of BC against CP.     

Anticlastogenic effects of black tea (World blend) and its two active polyphenols theaflavins and thearubigins in vivo in Swiss albino mice.

This study investigated the inhibition of cyclophosphamide (CP) and dimethylbenz(a)anthracene (DMBA) induced genetic damage by black tea (World blend) and its two active polyphenols theaflavins (TF) and thearubigins (TR) in Swiss albino mice as measured by chromosome aberrations (CA) and sister chromatid exchanges (SCE). Three different concentrations (5, 10 and 20%) of tea and a single dose of TF and TR were tested for their anticlastogenic effects against DMBA (50 mg/kg body weight) and CP (20 mg/kg for CA and 10 mg/kg for SCE). A significant decrease in CA was observed in all the three concentrations of tea extract plus DMBA treated groups when compared with the respective DMBA treated group alone. Similarly a significant decrease in CA was observed in all the three concentrations of tea extracts plus CP treated series when compared with the group treated with CP alone. In SCE assay, a significant decrease in SCE was observed in 5, 10 and 20% black tea extract plus CP and 10 and 20% tea extracts plus DMBA treated groups when compared with the CP or DMBA treated group alone. In the single dose of TF and TR treated groups a significant decrease in both CA and SCE was observed in both the TF and TR plus both the carcinogen treated groups when compared with their positive controls. The protective effects of black tea extracts were more significant than that of its two polyphenols. This study indicates that both black tea and its active polyphenols TF and TR have significant anticlastogenic effects in bone marrow cells of mice.     

Immunomodulatory effects of alcbholic and hydroalcoholic extracts of Moringa olifera Lam leaves

Effects of 50, 100 and 200 mg/kg body weight of the alcoholic and hydro-alcoholic extract of leaves of M. olifera were studied on various immune paradigms like delayed type hypersensitivity reaction using SRBC as an antigen, determination of antibody titer, neutrophil adhesion test as an indicator for neutrophil index, total leucocyte count in cyclophosphamide induced immunosuppressed animals and carbon clearance assay as a measure of phagocytic activity. Hydro-alcoholic extract of M. olifera substantially enhanced cellular immune response, humoral immune response, neutrophil index and phagoctic activity in doses of 100 and 200 mg/kg body weight. The ethanolic extract (200 mg/kg body weight) was efficient in improving immune response. The results suggest that M. olifera has a significant role to play as an immune stimulator.     

Antimutagenic effect of an antioxidant in mammals

To test a possible antimutagenic activity of ethoxyquin (EQ) in bone-marrow cells, 3 cytogenetic tests with distinct genetic end-points were applied. Cyclophosphamide (CPA), serving as test mutagen, and the antioxidant EQ were administered immediately following each other to Chinese hamsters by stomach tube. Whereas the CPA dose was the same in each test, the EQ doses were increased up to a ratio of CPA/EQ = 1:25, in some cases up to 1:50. The formation of SCEs induced by CPA was not influenced by EQ--even at the highest dose. In the micronucleus test, however, EQ drastically reduced the micronucleus rate even at the lowest dose applied (20 mg/kg) and abolished the CPA effects at a dose of 100 mg/kg. This action of EQ against CPA was also found in the rat and mouse in the micronucleus test system. Two inbred strains of mouse showed similar reactions, but the induced micronucleus rate was higher and its decrease in response to increasing doses of EQ was more delayed. In the chromosome aberration test, EQ also showed a distinct anticlastogenic response. At higher EQ doses, all CPA-induced chromosomal damage was reduced down to the level of spontaneous rates. The anticlastogenic effect of EQ was quantitatively similar in the micronucleus and chromosome aberration tests. Only minor qualitative differences were recognizable.     

Antioxidant effects of Emblica officinalis and Zingiber officinalis on arsenic and lead induced toxicity on Albino rats

It is of interest to document the effect of Emblica officinalis (E. officinalis) and Zingiber officinalae (Z. officinalae) leaf extract on reactive oxygen species, antioxidant potential changes in arsenic and lead-induced toxicity in male rats. We used 8 groups of adult male Wistar rats with 1 control group for this study. The animals were divided into Group I: Control and Group II: Lead and sodium arsenite induced rats (animals were induced for metal toxicity by the combined administration of arsenic (13.8 mg/ kg body weight) and lead (116.4 mg/kg body weight). These doses were administered by gastric intubation during 14 consecutive days using known standard procedures. Arsenic and lead induced rats treated with ethanolic extract of Emblica officinalis (60 mg/kg body weight/day, orally for 45 days) are group III rats. Group IV animals are arsenic and lead induced rats treated orally with ethanolic extracts of E. officinalis (120 mg/kg body weight/day for 45 days). Group V animals are arsenic and lead induced rats treated orally with ethanolic extracts of Z. officinalae (60 mg/kg body weight/day for 45 days). Group VI animals are arsenic and lead induced rats orally treated with ethanolic extracts of Zingiber officinalis (120 mg/kg body weight/day for 45 days). Group VII animals are arsenic and lead induced rats treated orally with ethanolic extracts of E. officinalis and Z. officinalae (60 + 60 mg/kg body weight/day for 45 days). Group VIII animals are arsenic and lead induced rats treated orally with ethanolic extracts of E. officinalis and Z. officinalae (120 + 120 mg/kg body weight/day, orally for 45 days). Normal Control animals were treated orally with ethanolic extracts of E. officinalis (120mg/kg body weight) + Z. officinalae (120mg/kg body weight) for 45 days. The control and experimental animals were then subjected to analysis for oxidative stress markers such as H2O2, *OH, and lipid peroxidation (LPO), antioxidant enzymes in addition to liver and kidney function markers. Results: Arsenic and lead induced rats showed a significant increase in the levels of reactive oxygen species (H2O2, OH* and LPO) with concomitant alterations in the renal and liver tissues. However, enzymic and non-enzymic antioxidant levels were decreased. Nevertheless, an oral effective dose of E. officinalis and Z. officinalae (120 + 120 mg/kg body weight/day increased the antioxidant enzymes and retrieved the altered levels of ROS and LPO that were induced by arsenic and lead. Thus, we show that E. officinalis and Z. officinalae leaf extract exhibits nephroprotective and hepatoprotective role through the restoration of reactive oxygen species and antioxidant enzymes in the kidney and liver tissue of Arsenic and Lead-induced nephrotoxicity and hepatotoxicity in rats. Hence, E. officinalis and Z. officinalae leaf extract are potential therapeutic options for the treatment of metal toxicity-induced kidney and liver diseases.     

Assessment of the mutagenic, antimutagenic and cytotoxic activities of ethanolic extract of araticum (Annona crassiflora Mart. 1841) by micronucleus test in mice.

A typical Brazilian plant, araticum (Annona crassiflora Mart.), is widely used in humans as therapeutic medicine to treat several diseases such as diarrhea, rheumatism and syphilis. It contains acetogenins which present cytotoxic, antitumogenic, and antiparasitic properties. In this study, mutagenic, antimutagenic and cytotoxic effects of araticum leaves ethanolic extract were evaluated by micronucleus test in mice. To evaluate the mutagenic activity, animals were treated with ethanolic extract of araticum (EEA) using 10, 20, 50, 100 and 160 mg.kg(-1). For all doses, micronucleated polychromatic erythrocytes (MNPCE) frequency was evaluated at 24, 48 and 72 hours after treatment. To evaluate the antimutagenic activity, animals were treated with 10, 20, 50 and 100 mg.kg(-1) of EEA and 4 mg.kg(-1) of MMC simultaneously. The frequency of MNPCE was evaluated 36 hours after exposure. Cytotoxicity was evaluated by the polychromatic and normochromatic erythrocytes ratio (PCE/NCE). In the mutagenicity assessment, all doses of EEA resulted in no significant increase of MNPCE (P > 0.05), compared to solvent- control group. Regarding administration time, no significant difference among three evaluation periods was observed (P > 0.05). Such results indicate that EEA did not exert mutagenic activity. Cytotoxicity was evident in doses of 50, 100 and 160 mg.kg(-1) at 24 and 48 hours after exposure. Concerning antimutagenicity, except the 10 mg.kg(-1) co-administered with 4 mg/kg of MMC, all doses reduced significantly the frequency of MNPCE compared to the positive control group (P < 0.05). These results, therefore, indicate an antimutagenic activity of the EEA. Cytotoxicity was significantly increased (P < 0.01) at 100 mg.kg(-1) EEA doses co-administered with 4 mg.kg(-1) of MMC.     

Anticlastogenicity of two derivatives of 1,4-dihydroisonicotinic acid in mouse micronucleus test

Effects of two derivatives of 1,4-dihydroisonicotinic acid (1,4-DHINA) against the monofunctional alkylating agent ethyl methanesulfonate (EMS) were studied in the micronucleus test in (CBA x C57Bl/6(j)) mice. Adult males and pregnant females were treated with an antimutagen (i.p.) and 12h later they were exposed to EMS (i.p.). The frequencies of micronucleated (MN) polychromatic erythrocytes (PCEs) in mouse bone marrow and foetal liver were analysed 6, 12, 18, 24, 30, 36, 48 or 24, 48 and 72 h after the mutagen injection. In adults, the maximum number of MNPCEs was observed 36 or 24h after the EMS administration. In foetuses, which were treated in a maternal organism, such peak was found at 24h. Pre-treatment of mice with the antimutagens 2,6-dimethyl-3,5-diethoxycarbonyl-4-(Na carboxylate)-1,4-dihydropyridine (DHP) and glutapyrone (GP) decreased the yield of MNPCEs in male bone marrow. Having been observed at a peak of MN induction, the anticlastogenic effect of DHP (1/10 LD(50) or 340 mg/kg) reached 30%. DHP at the doses of 0.5-1mM/kg did not affect the EMS-induced frequency of MNPCEs in bone marrow, whereas GP inhibited it at the similar millimolar concentrations. Simultaneously with maternal bone marrow, foetal liver cells were analysed for MNs in the transplacental test. The anticlastogenic effect of DHP (1/10 LD(50)) was found to be more prolonged and higher in females than in males and to average 50%, but this antimutagen was not efficient in foetuses. Both antimutagens did not change the polychromatic/normochromatic erythrocyte (PCE/NCE) ratio as compared with EMS action.Results presented indicate a peak of EMS-induced micronucleated cells in mouse bone marrow 24 or 36 h and in foetal liver 24h after animal treatment. Two 1,4-DHINA derivatives exhibited anticlastogenic activity in adults, but not in foetuses.     

Detection of micronuclei after exposure to mitomycin C, cyclophosphamide and diethylnitrosamine by the in vivo micronucleus test in mouse splenocytes.

A micronucleus detection test using mouse splenocytes has been adapted from a method previously carried out using human lymphocytes. An ex vivo protocol was chosen: male C57B16 mice were treated with various compounds. Splenocytes were then isolated and placed in culture for 48 h and stimulated with concanavalin A and conditioned medium. The cytokinesis-block method reported by Fenech and Morley was used to detect and score micronuclei in the proliferating lymphocytes (3 micrograms/ml of cytochalasin B for 16 h). Three mutagenic clastogens, mitomycin C (MMC), a direct alkylating agent (0.4, 0.8 and 1.6 mg/kg), cyclophosphamide (CP), an indirect alkylating agent (25, 50 and 100 mg/kg) and diethylnitrosamine (DEN), an indirect alkylating agent with labile metabolites (25, 50 and 100 mg/kg), were tested at four sampling times (2, 4, 8 and 15 days). All three compounds were detected from 48 h after treatment. This method was indeed able to detect clastogenic compounds normally detected by the mouse bone marrow micronucleus test (MMC, CP) as well as a compound with labile metabolites which is not usually detected by this test (DEN). Maximum micronucleus induction was observed after 4 days for MMC, 2 days for CP and 15 days for DEN. This method thus appears to offer a potentially useful toxicological test for assessing in vivo clastogenicity.     

Modification of cyclophosphamide-induced clastogenesis and apoptosis in rats by alpha-lipoic acid

The aim of the present study was to investigate the protective efficacy of alpha-lipoic acid (LA) on the cyclophosphamide (CP)-induced chromosomal aberrations (CA) and apoptosis in the bone marrow of rats. Male Wistar rats of 140+/-20 g were categorized into eight groups. Five groups were administered CP (40 mg/kg body weight, intraperitoneally) to induce toxicity; four of these groups received a single intraperitoneal injection of LA at a dose of either 100 or 200 mg/kg body weight, and either 30 or 60 min prior to CP administration. A vehicle-treated control group and LA control groups were also included. Twenty-four hours after CP treatment, the frequency of CA in bone marrow cells were significantly increased in comparison with the controls. The CP-induced CA were associated with significant increase in DNA damage in the bone marrow as evidenced by increased single strand breaks, whereas in rats treated with LA and CP, the frequency of CA and single strand breaks were significantly decreased in comparison to those given CP alone. CP administration distinctly triggered the apoptotic and necrotic cell death, and LA pretreatment affected cell death by decreasing the number of apoptotic and necrotic cells. The protective effect of LA was found to be stronger at a dose of 200 mg/kg body weight than 100 mg/kg body weight dosage, indicating the dose dependent protective effect of LA. However, the protection by LA was not dependent on the time intervals between LA and CP administration. The results of this study illustrate the protective effect of LA on the CA and apoptosis induced by CP in the erythropoietic system of rats.     

Immunomodulatory effect of Moringa oleifera Lam. extract on cyclophosphamide induced toxicity in mice

Immunomodulatory effect of ethanolic extract (50%) of M. oleifera leaves (MOE) has been studied in normal and immunosuppressed mice models. Different doses of MOE i.e. 125, 250 and 500 mg/kg body weight of mice were administered orally for 15 days. Cyclophosphamide at a dose of 30 mg/kg body weight was administered orally for the next 3 days. On day 16 and 19, hematological parameters like white blood cell (WBC) count, red blood cell (RBC) count, haemoglobin level (Hb), percent neutrophils and organ weight were recorded. Effect of MOE on phagocytic activity of mice macrophages was determined by carbon clearance test. MOE showed significant dose dependent increase in WBC, percent neutrophils, weight of thymus and spleen along with phagocytic index in normal and immunosuppressed mice. The results indicate that MOE significantly reduced cyclophosphamide induced immunosuppression by stimulating both cellular and humoral immunity.     

Protective effect of RH-3 with special reference to radiation induced micronuclei in mouse bone marrow

Effect of pre-irradiation administration of different doses of RH-3, the herbal preparation of an Indian medicinal plant Hippophae rhamnoides, 30 min before 10 Gy whole body gamma irradiation was studied. Doses between 25 to 35 mg/kg body wt. were found to render > 80 % survival in mice. In order to investigate whether RH-3 protected against radiation induced genotoxicity, mice were administered different doses of RH-3, 30 min before 2 Gy dose and compared with untreated, RH-3 treated and irradiated controls. The bone marrow cells were collected at different time intervals following various treatments and processed for scoring micronuclei (MN). Administration of RH-3 alone did not enhance the MN frequency as compared to the control, and radiation dose of 2 Gy significantly enhanced the MN frequency (3.1 %, P < 0.01). Pre-irradiation treatment with RH-3, however, reduced the radiation induced MN frequency in a drug dose dependent manner suggesting its radioprotective efficacy. The protective effect of RH-3 on radiation induced perturbations in cell cycle progression was studied flowcytometrically in mouse bone marrow cells. RH-3 treatment (30 mg/kg body wt.) enhanced DNA synthesis (S-phase) in unirradiated controls and also countered radiation induced depression of S-phase to facilitate replenishment of cells lost due to radiation injury.     

Captopril protects mice bone marrow cells against genotoxicity induced by gamma irradiation

The radioprotective effects of captopril were investigated by using the micronucleus test for anticlastogenic and cell proliferation activity. A single intraperitoneal administration of captopril at doses of 10, 25 and 50 mg/kg 1 h prior to gamma irradiation (2 Gy) reduced the frequencies of micronuleated polychromatic erythrocytes (MnPCEs). All three doses of captopril significantly reduced the frequencies of MnPCEs and increased polychromatic erythrocytes (PCE)/PCE+NCE (normochromatic erythrocyte) ratio in mice bone marrow compared to the non-drug-treated irradiated control (p < 0.001). The optimum dose for protection in mouse was 10 mg/kg to protect mice bone marrow 2.18-fold against the clastogenic effects of gamma-irradiation with respect to the non-drug-treated irradiated control. There was a drug dose-response effect of captopril in increasing the PCE/PCE+NCE ratio in bone marrow cells. The maximum protective effect of captopril was at a dose of 25 mg/kg for increasing the PCE/PCE + NCE ratio. Captopril exhibited concentration-dependent antioxidant activity, scavenging > 96% of the 1,1-diphenyl-2-picryl hydrazyl free radicals when used at a concentration of 0.2 mM. In this study captopril reduced lipid peroxidation induced by hydrogen peroxide in mice liver. It appears that captopril, due to its free radical scavenging properties, protects mice bone marrow cells from radiation-induced DNA damage and genotoxicity.     

Suppression of mitomycin C-induced micronuclei in mouse bone marrow cells by post-treatment with vanillin

Induction of micronuclei by mitomycin C (MMC) in mouse bone marrow cells was suppressed by post-treatment with vanillin, a component of vanilla essence flavour. Vanillin was given orally to mice 7.5 h after intraperitoneal injection of 2 mg/kg MMC. Post-treatment with vanillin at 500 mg/kg caused about 50% decrease in the frequency of micronucleated polychromatic erythrocytes (MN-PCEs). The effect of vanillin administration on the time-course of formation of MN-PCEs was also investigated. The suppressing effect was not due to a delay in the formation of MN-PCEs by the cytotoxic action of vanillin. Vanillin acts as an anticlastogenic factor in vivo.     

Antimutagenic potential of curcumin on chromosomal aberrations in Wistar rats

Curcumin, a yellow pigment commonly used as a spice and food coloring agent is obtained from rhizomes of Curcuma longa and is a major chemopreventive component of turmeric. In the present set of investigations the antimutagenic potential of curcumin has been evaluated using in vivo chromosomal aberration assay in Wistar rats. Cyclophosphamide (CP), a well-known mutagen was given by intraperitoneal (i.p.) injection at the dose of 40 mg/kg body weight (b.w.). Curcumin was given at the dose of 100 and 200 mg/kg b.w. through gastric intubation for seven consecutive days prior to CP treatment. The animals were sacrificed at the sampling time of 24 h after treatment and their bone marrow tissue was analyzed for chromosomal damage and mitotic index. In CP treated animals a significant induction of chromosomal aberration was recorded with decrease in mitotic index. However, in curcumin-supplemented animals, no significant induction in chromosomal damage or change in mitotic index was recorded. In different curcumin-supplemented groups, a dose dependent significant decrease in CP induced clastogenicity was recorded. The incidence of aberrant cells was found to be reduced by both the doses of curcumin when compared to CP treated group. The anticytotoxic potential of curcumin towards CP was also evident as the status of mitotic index was found to show increment. The study revealed the antigenotoxic potential of curcumin against CP induced chromosomal mutations.     

Role of quercetin on mitomycin C induced genotoxicity: analysis of micronucleus and chromosome aberrations in vivo

Quercetin, a flavonol group of plant flavonoid, has generated immense interest because of its potential antioxidant, anti-proliferative, chemoprotective, anti-inflammatory and gene expression modulating properties. However, the pro-oxidant chemistry of quercetin is important as it is related to the generation of mutagenic quinone-type metabolites. In the present study, 25mg/kg, 50mg/kg and 100mg/kg of quercetin given through the intra peritoneal (i.p.) route induced 2.31 ± 0.27%, 4.72 ± 0.58% and 6.38 ± 0.68% (control value=0.67 ± 0.30%) respectively, of cells with micronucleus (MN) in polychromatic erythrocytes in bone marrow cells and 10.93 ± 0.98%, 10.00 ± 0.89% and 14.27 ± 3.94% (control 2.61 ± 0.48) of cells with chromosome aberrations (CA) following 24h of the treatments. Higher frequencies of MN and CA were also observed after 48h of the treatments. To verify the effect of route of treatment on the quercetin induced damage, 100mg/kg b.w. was given through oral route which declined frequency of MN (P<0.001) as well as CA (P<0.05) as compared to the i.p. route for the same dose. Quercetin also induced higher frequency of metaphases with sticky chromosomes and C-mitosis. Pre-treatment with quercetin significantly reduced the frequency of mitomycin C (MMC) induced MN as well as CA, but no clear correlation between the dose and effect could be observed. Further studies are required to elucidate the possible interaction of quercetin with DNA as well as with other DNA damaging agents like MMC in vivo. The protective action of quercetin was not enhanced when given orally. Our findings suggest that quercetin may result in genomic instability in the tested dose range and significant reduction in MMC induced genotoxicity in the highest dose tested. These effects of quercetin are to be taken into consideration while evaluating the possible use of quercetin as a therapeutic agent.     

Maternal and fetal chromosomal aberrations in mice following prenatal exposure to subembryotoxic doses of lead nitrate

Maternal exposure to low levels of lead nitrate (12.5, 25, 50 mg/kg body weight), administered on the 9th day of gestation, did not cause embryonic resorption and fetal lethality, but induced chromosomal deletions and other forms of aberrations in fetal liver and maternal bone marrow cells.     

Reproductive toxicologic evaluations of Bulbine natalensis Baker stem extract in albino rats

The effects of oral administration of aqueous extract of Bulbine natalensis Baker stem at daily doses of 25, 50, and 100 mg/kg body weight on the reproductive function of Wistar rats were evaluated. The indices of mating and fertility success as well as quantal frequency increased after 7 days of treatment in all the dose groups except the 100 mg/kg body weight group. The number of litters was not statistically different (P > 0.05) from the control. Whereas the absolute weights of the epididymis, seminal vesicle, and prostate were not affected, that of the testes was significantly increased. The epididymal sperm count, motility, morphology, and viscosity were not different from the control after 7 days of treatment. The male rat serum testosterone, progesterone, luteinizing hormone, and follicle-stimulating hormone significantly increased in the 25 and 50 mg/kg body weight groups, whereas the estradiol concentration decreased significantly at all the doses. The extract dose of 100 mg/kg body weight decreased the serum testosterone and progesterone levels in male rats. The prolactin concentration was not affected by all the doses. All the indices of reproduction, maternal, embryo/fetotoxic, teratogenic, and reproductive hormones in the female rats were not statistically different from that of their control except the resorption index, which increased at the dose of 100 mg/kg body weight of the extract. Histologic examination of the cross section of rat testes that received the extract at all the doses investigated revealed well-preserved seminiferous tubules with normal amount of stroma, normal population of spermatogenic and supporting cells, as well as normal spermatocytes within the lumen. The results revealed that the aqueous extract of Bulbine natalensis stem at doses of 25 and 50 mg/kg body weight enhanced the success rate of mating and fertility due to increased libido as well as the levels of reproductive hormones in male rats. The absence of alterations in the reproductive parameters of female rats at doses of 25 and 50 mg/kg body weight of Bulbine natalensis stem extract suggest that the extract is “safe” for use at these doses by females during the organogenic period of pregnancy, whereas the extract dose of 100 mg/kg body weight portends a negative effect on some reproductive functions of male and female rats.     

Potentiation by caffeine of the frequencies of micronuclei induced by mitomycin C and cyclophosphamide in young mice

Employing the micronucleus test in mouse bone marrow and in fetal mouse liver, the possible clastogenicity of caffeine as well as its influence on MMC- and CP-induced micronucleus levels were studied. The treatment of male and female C57Bl or BDF1 (C57Bl x DBA2) mice with caffeine (1 or 3 x 50 mg/kg and 100 mg/kg, s.c.) had no clastogenic effect in mouse bone marrow or in the fetal livers and maternal bone marrow when pregnant mice were injected with caffeine on day 16-17 of gestation. MMC (2.0 mg/kg, i.p.) increased up to 10-30-fold the number of MNPCEs in bone marrow compared to a 3-7 fold elevation of MNPCEs in fetal liver. A similar effect was also established in pregnant mice treated with CP (30 mg/kg, i.p.). No significant sex differences in spontaneous and MMC- or CP-induced MNPCEs levels were established in C57Bl and BDF1 mice. However, a significantly higher spontaneous rate of MNPCEs as well as a better-expressed responsiveness to the clastogenic activity of MMC and CP were established in C57Bl compared to BDF1 mice. The pregnancy had no effect on MMC- or CP-induced clastogenicity although a tendency to a decreased sensitivity to the damaging activity of MMC seemed to be detected in pregnant C57Bl mice compared to virgin female animals. The combined treatment of mice with caffeine (3 x 100 mg/kg) and MMC or CP caused an up to 45-49% potentiation of clastogenesis in the bone marrow of male, female and pregnant female C57Bl and BDF1 mice but not in fetal mouse livers.     

Acute and sub-acute toxicity of ethanolic extract of Canthium mannii Hiern stem bark on Mus musculus

Acute and sub-acute toxicity of ethanolic extract (ETE) of C. mannii was assessed on white mice (Mus musculus). After 48 h of extract administration, no death was registered. It was deduced that the LD50 was indisputably higher than 16 g/kg body weight. The sub-acute toxicity test was based on the daily administration of three doses of ETE (300, 600 and 1200 mg/kg body weight) for four weeks; 1% DMSO served as negative control. As for the first experiment, no sign of toxicity was registered. Conversely, the sub acute doses stimulated and increased the weight-rate of mice after 7 days of treatment. Except for the spleen weight, the doses administrated did not modify the weight index. It was observed that, subacute doses induced and increased (a) the food (particularly) and water consumption according to time and (b) the number of red and white blood cells. It was thought that, ETE can stimulate the haematopoietic function. Finally, no time variation of the activity of alanine aminotransferase and aspartate aminotransferase enzyme was observed in the serum of euthanized mice. The results showed the innocuity of ETE of C. mannii and thus validated his utilization in cameroonian traditional pharmacopoea.     

Anti-inflammatory and analgesic activity of Indian Hypericum perforatum L

A standardised 50% aqueous ethanolic extract of the Indian variety of Hypericum perforatum (IHp) was examined for its putative anti-inflammatory and analgesic activity at the doses of 100 and 200 mg/kg, po. The experimental paradigms used were carrageenan induced pedal edema and cotton pellet induced granuloma for anti-inflammatory activity, whereas the tail flick, hot plate and acetic acid induced writhing methods were used to asses analgesic activity. Indomethacin (20 mg/kg, ip) was used as the standard anti-inflammatory drug. Pentazocine (10 mg/kg, ip) and aspirin (25 mg/kg, ip), both clinically used analgesics, were used as standard analgesics for comparison. IHp extract showed significant anti-inflammatory and analgesic activity at both dose levels, in all the paradigms used. Additionally, IHp potentiated the anti-inflammatory activity of indomethacin and analgesic activities of pentazocine and aspirin.