ABSTRACT
The increased generation of free radicals plays an important role in testicular damage. The present study aimed to investigate the adverse effects of carbon tetrachloride (CCl4) on the reproductive system of male rats as well as to examine whether Vitamin E (VE) is able to ameliorate these effects. The rats were equally divided into three groups: control, CCl4-treated, and CCl4 + VE-treated groups. After 4 weeks of treatment, the decrease in body and testes weights, sperm parameters, and the decrease in serum levels of testosterone, luteinizing hormone, and follicle-stimulating hormone of CCl4-treated rats were ameliorated by VE treatment. The co-administration of VE with CCl4 significantly decreased the level of lipid peroxidation production (malondialdehyde) and increased the activity of anti-oxidant enzymes (superoxide dismutase and catalase) when compared with the CCl4 group. Moreover, VE prevented CCl4-induced severe testicular histopathological lesions and deformities in spermatogenesis. The results demonstrate that VE augments the anti-oxidants' defense mechanism against CCl4-induced reproductive toxicity suggesting a therapeutic role in free radical-mediated infertility.
Subject(s)
Carbon Tetrachloride/toxicity , Cytoprotection/drug effects , Spermatozoa/drug effects , Testis/drug effects , Vitamin E/pharmacology , Animals , Antioxidants/pharmacology , Lipid Peroxidation/drug effects , Male , Oxidative Stress/drug effects , Rats , Spermatogenesis/drug effects , Spermatozoa/physiology , Testis/physiologyABSTRACT
Chloramphenicol has been associated with the development of aplastic anaemia. As it is still widely used in Egypt, we studied its effect on 100 Egyptian toads (Bufo regularis) given a dose of chloramphenicol of 5 mg/40 g body weight for 12 weeks. We found it induced numerous, severe ultrastructural changes in almost all types of leukocytes. These changes were similar to those induced by the chemical carcinogen 7,12-dimethylbenz(a)anthracene in 100 toads used as the carcinogen control group, and similar to those in leukocytes reported in humans with leukaemia. We recommend regulations be applied on the use of this antibiotic in countries where it is still widely used.
Subject(s)
Anti-Bacterial Agents/poisoning , Chloramphenicol/poisoning , Disease Models, Animal , Leukemia/chemically induced , 9,10-Dimethyl-1,2-benzanthracene/poisoning , Animals , Anti-Bacterial Agents/therapeutic use , Body Weight , Bufonidae , Carcinogens/adverse effects , Chloramphenicol/therapeutic use , Drug Evaluation, Preclinical , Drug Utilization , Egypt , Erythrocytes/drug effects , Erythrocytes/ultrastructure , Female , Incidence , Leukemia/blood , Leukemia/pathology , Male , Practice Patterns, Physicians'/statistics & numerical dataABSTRACT
The effect of retinoids on spermatogenesis in adult male gerbils (Gerbillus cheesemani) was studied using light and electron microscopy. Treatment with either 13-cis-retinoic acid or retinol acetate was given for 6 weeks and their effects were compared with controls. It was found that 13-cis-retinoic acid induced almost complete cessation of spermatogenesis and produced alterations in the cytoplasm of Leydig cells. No differences were seen in the testis of animals treated with retinol acetate compared with controls using light microscopy but it appeared to produce noticeable ultrastructural changes in Leydig cells. The changes observed were reversed 12 weeks after stopping treatment. Caution should be exercised regarding the use of dietary retinoids in the prevention of cancer.
Subject(s)
Anticarcinogenic Agents/adverse effects , Isotretinoin/adverse effects , Spermatogenesis/drug effects , Vitamin A/analogs & derivatives , Animals , Diterpenes , Drug Evaluation, Preclinical , Gerbillinae , Leydig Cells/drug effects , Leydig Cells/ultrastructure , Male , Microscopy, Electron , Retinyl Esters , Seminiferous Tubules/drug effects , Seminiferous Tubules/ultrastructure , Time Factors , Vitamin A/adverse effectsABSTRACT
The effect of retinoids on spermatogenesis in adult male gerbils [Gerbillus cheesemani] was studied using light and electron microscopy. Treatment with either 13-cis-retinoic acid or retinol acetate was given for 6 weeks and their effects were compared with controls. It was found that 13-cis-retinoic acid induced almost complete cessation of spermatogenesis and produced alterations in the cytoplasm of Leydig cells. No differences were seen in the testis of animals treated with retinol acetate compared with controls using light microscopy but it appeared to produce noticeable ultrastructural changes in Leydig cells. The changes observed were reversed 12 weeks after stopping treatment. Caution should be exercised regarding the use of dietary retinoids in the prevention of cancer
Subject(s)
Anticarcinogenic Agents , Drug Evaluation, Preclinical , Gerbillinae , Isotretinoin , Leydig Cells , Microscopy, Electron , Seminiferous Tubules , Time Factors , Vitamin A , SpermatogenesisABSTRACT
Environmental factors play an important role in the etiology of several types of cancer; this discovery has led to a great deal of interest in the role of diet in cancer etiology. It is well known that some factories which produce jams and juices use fructose rather than glucose or sucrose to sweeten their products. This study demonstrates that fructose insignificantly enhances the incidence of liver tumours in Egyptian toads previously injected with 7,12-dimethylbenz [a]-anthracene
Subject(s)
Liver Neoplasms , Fructose , Anura , Life Style , Carbohydrates , DIET , Lipids , Energy IntakeABSTRACT
An analysis of residues from anabolic agents found in commercially available meat and poultry was undertaken in Alexandria, Egypt. This study shows that beef meat samples purchased from government cooperative supermarkets exhibit higher levels of the synthetic growth promoter, trenbolone acetate, than meat from private butchers; however, estrogen levels were much higher in chicken obtained from private growers. A comparison of different cooking methods was conducted on the chicken samples; boiling without skin is recommended to reduce the consumer's intake of hormonal residues
Subject(s)
Hormones , Meat , Anabolic Agents , Chickens , Food AnalysisABSTRACT
Toads fed with 0.5 mg 7,12-dimethylbenz(a)anthracene twice a week for 12 weeks displayed liver tumors in 27 out of 100 cases. Electron micrographs of liver tumors showed some criteria of malignancy, such as the presence of nuclear pockets, pseudoinclusions, dilatation of the cisternae of rough endoplasmic reticulum and loss of cell junctions. These features are closely similar to those of true malignancy described in humans and other mammals.
Subject(s)
Liver Neoplasms, Experimental/ultrastructure , Neoplasms/ultrastructure , 9,10-Dimethyl-1,2-benzanthracene , Animals , Bufonidae , Female , Humans , Liver Neoplasms, Experimental/chemically induced , Male , Microscopy, Electron , Rana pipiens , Xenopus laevisABSTRACT
Hepatocellular carcinoma were recognized in the toad, Bufo viridis, in 14 cases out of 50 by injection of 1 mg 7,12 dimethylbenz(a)anthracene (DMBA)/toad twice/week for 12 weeks. In contrast, toads treated with DMB at the same dose level and beta-carotene (betaC), 0.05 mg (3 hr prior to the carcinogen)/toad, twice/week for 12 weeks showed no tumor incidence. However, betaC at the same dose level was less effective when administered 3 hr. after the carcinogen (DMBA). In 8 cases out of 50 cases neither tumor growth nor neoplastic changes were observed in toads treated with betaC alone or olive oil. It is concluded that betaC completely blocked hepatocarcinogenesis in toads when given 3 hr. before initiation.
Subject(s)
Antioxidants/therapeutic use , Liver Neoplasms, Experimental/prevention & control , beta Carotene/therapeutic use , 9,10-Dimethyl-1,2-benzanthracene/toxicity , Animals , Bufonidae , Carcinogens/toxicity , Drug Interactions , Female , Liver Neoplasms, Experimental/chemically induced , MaleABSTRACT
Toads injected with 2 mg 7,12-dimethyl-benza(a)anthracene (DMBA)/toad, 3 times/week for 12 weeks induced liver tumors in 12 out of 50 cases. The electron micrograph of toad liver tumor showed disorganization of the rough endoplasmic reticulum which encircles or partially surrounds the mitochondria. Cristae mitochondrialis are rare in comparison with control. Enhancement of liver tumor incidences (29 out of 50 cases) by DMBA at the same dose level plus 2cc corn oil/toad, 3 times/week for 12 weeks was detected. Electronicrograph of this group showed the same criteria of malignancy as in the first group. No tumor incidences were detected in toads fed corn oil only. The electronmicrograph of liver cells showed a high increase in glycogen and lipid droplets.
Subject(s)
9,10-Dimethyl-1,2-benzanthracene/pharmacology , Carcinogens/pharmacology , Dietary Fats , Liver Neoplasms/chemically induced , Animals , Bufonidae , Female , Liver Neoplasms/ultrastructure , MaleABSTRACT
The treatment of male Egyptian toads (Bufo regularis) with acrylamide (1 mg/toad twice a week for four weeks) was followed by atrophy of the testes, inhibition of spermatogenesis and necrosis of the seminiferous tubules with signs of vacuolation. Ultrastructurally, the Leydig cells of treated toads displayed varying degrees of vacuolation of the mitochondria, with a decrease in the number of ribosomes. The mechanism of the action of acrylamide in inhibiting spermatogenesis may be due to a decrease in the testosterone level, as borne out by vacuolation of the mitochondria and the decrease in the ribosomes in the Leydig cells of treated animals.
Subject(s)
Acrylamides/toxicity , Testis/drug effects , Acrylamide , Animals , Bufonidae , Male , Time FactorsABSTRACT
Egyptian toads, Bufo regularis, were fed with cholic acid (sodium salt) 3 times/week for 12 weeks at different dose levels (2.5, 5, and 10 mg/toad). Results obtained showed only 1 case in both the 5 and 10 mg/toad doses that gave a tumor. Toads receiving N-methyl-N-nitrosourea (MNU) 1 mg/toad, 3 times/week for 12 weeks had 36% ileum tumors (18 toads out of 50, without mortality). On the other hand, a higher dose of MNU (5 mg/toad) caused 50% mortality in the experimental animals. Toads treated with MNU at a dose level of 1 mg/toad were subjected to CA at dose levels of 2.5, 5, 10 mg/toad. They showed a 48, 66 and 76% higher incidence of ileum tumors at the three different dose levels, respectively. It is concluded that cholic acid has a promoting effect on ileum tumor evoked by MNU in toads as in mammals.
Subject(s)
Cholic Acids/toxicity , Ileal Neoplasms/chemically induced , Methylnitrosourea/toxicity , Animals , Bufonidae , Cholic Acid , Cocarcinogenesis , Dose-Response Relationship, DrugSubject(s)
Testis/pathology , Tretinoin/toxicity , Animals , Bufonidae , Male , Rats , Spermatogenesis/drug effects , Testis/drug effectsABSTRACT
20-Methylcholanthrene induced the encystment of Opalina ranarum when injected into its host, Rana ridibunda. Also, urine of frogs injected with this hydrocarbon induced encystment of the parasites. It is speculated that methylcholanthrene or its metabolites reach the parasites in the recta of the frogs and stimulate the parasites to encyst. Injections of frogs with methylcholanthrene and 13-cis-retinoic acid failed to induce cyst formation in the opalinids. Moreover, encystment of the parasite was lessened when the host was injected with methylcholanthrene and retinyl palmitate. Urine of frogs injected with methylcholanthrene and 13-cis-retinoic acid failed to induce cyst formation in the parasites. Moreover, urine of frogs injected with this hydrocarbon and retinyl palmitate lessened the induction of cyst formation in the parasites in vitro. It is suggested that 13-cis-retinoic acid as well as retinyl palmitate inhibits methylcholanthrene-induced cyst formation of the opalinids.
Subject(s)
Ciliophora/drug effects , Tretinoin/pharmacology , Vitamin A/analogs & derivatives , Animals , Ciliophora/physiology , Diterpenes , Female , Isotretinoin , Male , Methylcholanthrene/pharmacology , Ranidae , Retinyl Esters , Urine , Vitamin A/pharmacologyABSTRACT
Skin papillomas were observed in the majority of toads when painted with 1 mg of 7,12-dimethyl-benz (alpha) anthracene (DMBA) dialy for 8 weeks. Animals injected with 10 mg/kg/day of ascorbic acid into the dorsal lymph sac showed tumor inhibition when painted with the same dose level of DMBA for 8 weeks. Tumor regression occurred in those animals receiving 10 mg/kg/day of ascorbic acid for 8 weeks.
Subject(s)
Ascorbic Acid/therapeutic use , Papilloma/drug therapy , Skin Neoplasms/drug therapy , 9,10-Dimethyl-1,2-benzanthracene , Animals , Bufonidae , Female , Male , Neoplasms, Experimental/chemically induced , Neoplasms, Experimental/drug therapy , Papilloma/chemically induced , Skin Neoplasms/chemically inducedABSTRACT
Neoplasms of the liver were induced in 18 cases out of 44 in the Egyptian toad, Bufo regularis, by injection with 20-methylcholanthrene. Dose level was 10 mg/50 g body weight once a week. However, the injection of the same dose level of this hydrocarbon together with vitamin A palmitate on the level of 20,000 IU/50 g body weight once a week was found to develop hepatomas in the liver in only 1 of 45 cases. Results of this study indicate that vitamin A palmitate inhibited the carcinogenic effect of 20-methylcholanthrene.
Subject(s)
Liver Neoplasms, Experimental/chemically induced , Methylcholanthrene/antagonists & inhibitors , Vitamin A/analogs & derivatives , Animals , Bufonidae , Diterpenes , Female , Liver Neoplasms, Experimental/pathology , Male , Palmitates/pharmacology , Retinyl Esters , Vitamin A/pharmacologyABSTRACT
20-Methylcholanthrene induced cyst formation in Nyctotheroides puytoraci when injected into its host Bufo regularis. Presumably this hydrocarbon or its metabolites reaches the parasites in the recta of treated host animals and induces encystment. However, injection B. regularis with 0.5 mg of 20-methylcholanthrene + vitamin A palmitate (5,000 IU) inhibited the hydrocarbon-induced encystment of the parasites.
