The effect of four alkylating agents (MMS, EMs, DMN, DEM), under various con centrations on mouse bone marrow erythrocytes, were studied by means of the micronucleus test. The results obtained were as follows: 1) The lethal doses on mice were MMS = 130 mg/kg/bw, EMS = 300 mg/kg/bw, DMN = 50 mg/kg/bw and DEN = 70 mg/kg/bw. 2) Micronuclei were easily seen and in different controls the micronulei were found a little over 0.1%. 3) The dose-effect relationship was obtained. In the MMS and EMS treated groups, incidences of micronulei were 0.45 to 2.56% and 0.4 to 2.1% respectively. 4) In the DMN and DEN treated groups, incidences varied between 0.15 to 0.90 % and 0.2 to 1.02% respectively. 5) Four alkylating agents were compared and discussed with respect to micro nucleus production from chromosomal aberrations.
Animal ; Bone Marrow/ultrastructure ; Carcinogens/pharmacology* ; Cell Nucleus/drug effects* ; Chromosome Aberrations* ; Erythrocytes/ultrastructure ; Female ; Mesylates/pharmacology* ; Mice ; Mutagens/pharmacology ; Nitrosamines/pharmacology*

OBJECTIVETo investigate the protective effect of epigallocatechin gallate (EGCG) on mouse sperm in vivo.

METHODSA total of 64 six-week-old male Kuming mice were randomly divided into eight groups of equal number to be treated with normal saline (negative control), Cyclophosphamide (CP) at 30 mg/kg (positive control), and CP followed by EGCG (experimental) at 20, 40, and 80 mg/kg, respectively, given every other day for 10 days. At 4 and 5 weeks after treatment, the bilateral testes of the mice were harvested for examination of sperm abnormality.

RESULTSEGCG did not increase the rate of CP-induced sperm abnormality in the mice, but reduced it instead with the prolonged time of treatment.

CONCLUSIONEGCG protects mouse sperm in vivo.

Animals ; Catechin ; analogs & derivatives ; pharmacology ; Cyclophosphamide ; toxicity ; Male ; Mice ; Mutagens ; toxicity ; Random Allocation ; Spermatozoa ; drug effects ; Time Factors

OBJECTIVETo study the effect of hydroquinone on apoptosis of bone marrow mononuclear cells, and to evaluate the toxic effect of benzene on stem cells.

METHODSCell morphology was observed by HT fluorescent stain method, and DNA fragments were analyzed by agarose gel electrophoresis. Anti-Annexin V FITC plus PI staining for apoptotic and necrotic rate was examined by flow cytometer.

RESULTSAfter adding different concentrations of hydroquinone to the cells for 6 h culture, the fluorescent intensity of nucleus increased, the color of nucleus became deep and inhomogeneous, and the chromatin was condensed and distributed around the neucleus. DNA ladder was detected in all samples. Cell apoptotic rate in different concentration of hydroquinone groups was significantly higher than that in blank control group (P < 0.05). With the increase of the concentration of hydroquinone, the apoptotic and necrotic rate also increased. The optimal concentration of hydroquinone was 50 micro mol/L. When it was >or= 75 micro mol/L, the necrotic rate increased significantly. Hydroquinone-induced apoptosis was associated with culture time at the concentration of 50 micro mol/L, and the peak apoptotic time was 10 h, then the apoptotic rate decreased and necrotic rate increased.

CONCLUSIONHydroquinone can induce apoptosis of bone marrow mononuclear cells in vitro with dose-effect and time-effect relationship.

Apoptosis ; drug effects ; Bone Marrow Cells ; cytology ; Cells, Cultured ; Dose-Response Relationship, Drug ; Humans ; Hydroquinones ; pharmacology ; Leukocytes, Mononuclear ; cytology ; drug effects ; Mutagens ; pharmacology

Turmeric has long been used as a spice and food colouring agent in Asia. In the present investigation, the antimutagenic potential of curcumin was evaluated in Allium cepa root meristem cells. So far there is no report on the biological properties of curcumin in plant test systems. The root tip cells were treated with sodium azide at 200 and 300 microg/ml for 3 h and curcumin was given at 5, 10 and 20 microg/ml for 16 h, prior to sodium azide treatment. The tips were squashed after colchicine treatment and the cells were analyzed for chromosome aberration and mitotic index. Curcumin induces chromosomal aberration in Allium cepa root tip cells in an insignificant manner, when compared with untreated control. Sodium azide alone induces chromosomal aberrations significantly with increasing concentrations. The total number of aberrations was significantly reduced in root tip cells pretreated with curcumin. The study reveals that curcumin has antimutagenic potential against sodium azide induced chromosomal aberrations in Allium cepa root meristem cells. In addition, it showed mild cytotoxicity by reducing the percentage of mitotic index in all curcumin treated groups, but the mechanism of action remains unknown. The antimutagenic potential of curcumin is effective at 5 microg/ml in Allium cepa root meristem cells.
Antimutagenic Agents ; pharmacology ; Chromosome Aberrations ; drug effects ; Curcumin ; pharmacology ; Meristem ; drug effects ; genetics ; Mutagens ; toxicity ; Onions ; drug effects ; genetics ; Sodium Azide ; toxicity

The luminous intensity of dark variant (S1) separated from photobacterium phosphoreum (A2) was 1/10,000 less than that of wild-type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2-amino fluorene (2-AF, 1.0 mg/L) all could strongly induce reversion mutation for S1 within 24 h and increase reversion ratio significantly. The results of experiments indicated that these revertants had stable genetic characteristic and the mutation may take place at gene levels. The mutagenesis to S1 caused by EB, MC and 2-AF was detected and it may be used as a new rapid, simple and sensitive method for gene toxicant monitoring.
Ethidium ; pharmacology ; toxicity ; Genetic Variation ; Luciferases ; biosynthesis ; Luminescent Measurements ; Mitomycins ; pharmacology ; toxicity ; Mutagens ; Mutation ; drug effects ; Photobacterium ; genetics ; Toxicology ; methods ; Transcription, Genetic ; drug effects

The luminous intensity of dark variant (S1) separated from photobacterium phosphoreum (A2) was 1/10,000 less than that of wild-type. Ethidium bromide (EB) (0.6 mg/L), Mytomycin C (MC, 0.05 mg/L), 2-amino fluorene (2-AF, 1.0 mg/L) all could strongly induce reversion mutation for S1 within 24 h and increase reversion ratio significantly. The results of experiments indicated that these revertants had stable genetic characteristic and the mutation may take place at gene levels. The mutagenesis to S1 caused by EB, MC and 2-AF was detected and it may be used as a new rapid, simple and sensitive method for gene toxicant monitoring.
*Chemiluminescent Measurements ; Ethidium/pharmacology ; Ethidium/toxicity ; Luciferases/biosynthesis ; Mitomycins/pharmacology ; Mitomycins/toxicity ; Mutagens ; Mutation/*drug effects ; Photobacterium/*genetics ; Toxicology/methods ; Transcription, Genetic/drug effects ; Variation (Genetics)

OBJECTIVETo study the combined damage-effects of low-intensity 2,450 MHz microwave (MW) with three chemical mutagens on human lymphocyte DNA.

METHODSDNA damage of lymphocytes exposed to microwave and(or) with chemical mutagens were observed at different incubation time (0 h or 21 h) with comet assay in vitro. Three combination-exposure ways of MW with chemicals were used: MW irradiation before chemical exposures, simultaneously exposed to MW and chemicals and MW irradiation after chemical exposures. The three chemical mutagens were mitomycin C (MMC, DNA crosslinker), bleomycin (BLM, radiometric agent), methyl methanesulfonate (MMS, alkylating agent). The exposure time of MW and chemical mutagens were 2 h and 3 h respectively.

RESULTSThe differences of comet tail length between MW group and control group were not significant when lymphocytes were incubated for 0 h or 21 h (P > 0.05). However, when lymphocytes were incubated for 21 h with 30.00 micro mol/L of MMC, the comet tail lengths of MW + MMC group, MW-MMC group and MMC + MW group were (18.00 +/- 5.96), (21.79 +/- 11.47) and (22.32 +/- 8.10) micro m respectively; while with 3.00 micro mol/L of MMC, the comet tail lengths were (8.99 +/- 3.75), (12.40 +/- 5.35) and (14.00 +/- 5.38) micro m respectively, which were significantly higher than those of corresponding MMC groups [(9.42 +/- 3.34) and (6.50 +/- 2.89) micro m, P < 0.01 or P < 0.05]. The DNA damage of MW plus BLM groups and MW plus MMS groups were not significantly different from the corresponding BLM and MMS groups (P < 0.05).

CONCLUSION2 450 MHz MW (5 mW/cm(2)) did not induce DNA damage directly, but could enhance the DNA damage effects induced by MMC. The synergistic effects of 2 450 MHz MW with BLM and MMS were not obvious.

Bleomycin ; pharmacology ; Comet Assay ; DNA ; drug effects ; genetics ; radiation effects ; DNA Damage ; Humans ; Lymphocytes ; drug effects ; metabolism ; radiation effects ; Methyl Methanesulfonate ; pharmacology ; Microwaves ; adverse effects ; Mitomycin ; pharmacology ; Mutagens ; pharmacology ; Time Factors

AIMTo study the detrimental effects of cyclophosphamide on the testicular androgenic and gametogenic activities through endocrine inhibition and/or induction of oxidative stress in male albino rats and to evaluate the protective effect of ascorbic acid.

METHODSThe testicular D5, 3b-hydroxysteroid dehydrogenase (HSD), 17b-HSD, peroxidase and catalase activities along with the levels of malondialdehyde (MDA) and conjugated dienes in testicular tissue were measured for the evaluation of testicular oxidative stress. The plasma testosterone (T) level was measured by immunoassay. Various germ cells at stage VII of spermatogenic cycle were quantified from testicular stained sections.

RESULTSCyclophosphamide treatment results in a significant inhibition in the testicular D5, 3b-HSD and 17b-HSD activities, a decrease in plasma T level and a diminution in the counts of various germ cells. Moreover, this treatment was also associated with a significant inhibition of the peroxidase and catalase activities along with high levels of MDA and conjugated dienes in the testis. All these changes were reversed by ascorbic acid co-administration.

CONCLUSIONCyclophosphamide treatment at the dosage used caused testicular gametogenic and androgenic disorders as well as induced testicular oxidative stress that can be reversed by ascorbic acid co-administration.

Animals ; Antioxidants ; pharmacology ; Ascorbic Acid ; pharmacology ; Body Weight ; Catalase ; metabolism ; Cyclophosphamide ; pharmacology ; Hydroxysteroid Dehydrogenases ; metabolism ; Infertility, Male ; chemically induced ; drug therapy ; Lipid Peroxidation ; drug effects ; Male ; Mutagens ; pharmacology ; Peroxidase ; metabolism ; Rats ; Rats, Wistar ; Spermatogenesis ; drug effects ; Testosterone ; blood

OBJECTIVETo determine the in vitro possible clastogenic and cytotoxic activities of Ulva rigida crude extracts (URE), and identify their antigenotoxic and protective effects on chemotherapeutic agent mitomycine-C (MMC).

METHODSAnti-clastogenic and anti-genotoxic activities of Ulva rigida crude extracts (URE) were studied using chromosome aberration (CA), sister chromatid exchange (SCE), and micronuclei (MN) tests in human lymphocytes cultured in vitro.

RESULTSThe chromosome aberration, sister chromatid exchange or micronuclei tests showed that URE at concentrations of 10, 20, and 40 microg/mL had no clastogenic activity in human lymphocyte cell culture. Three doses of URE significantly decreased the number of chromosomal aberrations and the frequencies of SCE and MN when compared with the culture treated with MMC (P < 0.0001).

CONCLUSIONAlthough URE itself is not a clastogenic or cytotoxic substance, it possesses strong antigenotoxic, anti-clastogenic, and protective effects on MMC in vitro.

Antibiotics, Antineoplastic ; pharmacology ; Antimutagenic Agents ; pharmacology ; Cells, Cultured ; Chlorophyta ; Chromosome Aberrations ; drug effects ; Dose-Response Relationship, Drug ; Humans ; Lymphocytes ; drug effects ; metabolism ; Micronucleus Tests ; Mitomycins ; pharmacology ; Mutagens ; toxicity ; Plant Extracts ; chemistry ; pharmacology ; Sister Chromatid Exchange ; drug effects

OBJECTIVEThe purpose of this study was to investigate the effects of exogenous epidermal growth factor (EGF) on the growth inhibition of renal proximal tubular epithelial cell induced by AA-I.

METHODCultured human renal proximal tubular epithelial cell line HK-2 was used as the subject. The changes of the survived HK-2 cells were observed and compared among control, AA-I stimulation, pre-EGF, together-EGF and post-EGF groups. In the study, cellular morphologic assessments were performed with a phase-contrast inverted microscope. Cell counting after stained with 0.04% trypan blue was adopted to analyze cell proliferation. Cell cycle was assessed by flow cytometry.

RESULTNumber of the survived cells stimulated by AA-I for 12, 24, 48 hours decreased gradually in a dose and time dependent manner. At 24, 48 hours, the survived cells showed a significant disturbance in the cell cycle procedure, which was characterized as decreased percentage of cells in G0/G1 phase, significant increased percentage of cells in G2/M phases. Exogenous EGF (20 microg L(-1)) could significantly promote the proliferation of HK-2 cells, which shown a increased cell number, accompanied down-regulated cells in G0/G1 phase, increased cells in S and G2/M phase. Compared with AA-I groups, it failed to improve the inhibitory effect on cell proliferation and abnormal cell cycle procedure by AA-I, no matter EGF was added in before, at same time or after AA-I stimulation.

CONCLUSIONAA-I (10 g L(-1)) has remarkable growth inhibition effects on survived RTEC, and can induce a blockage of G2/M phase in the cell cycle procedure. Exogenous EGF (20 microg L(-1)) promote the proliferation in normal cultured HK-2 cell. EGF treatment could not improve the proliferation inhibitory effect induced by AA-I, no matter adding EGF to cultures before, together with AA-I or after AA-I stimulation.

Aristolochic Acids ; pharmacology ; Cell Cycle ; drug effects ; Cell Line ; Cell Proliferation ; drug effects ; Epidermal Growth Factor ; pharmacology ; Epithelial Cells ; drug effects ; Flow Cytometry ; Humans ; Kidney Tubules, Proximal ; cytology ; drug effects ; Mutagens ; pharmacology