Effects of Teratogenic Drugs on CYP1A1 Activity in Differentiating Rat Embryo Cells.

CYP1A1, a P450 isoenzyme, is involved in the phase I xenobiotic metabolism including teratogen drugs. In the present study, the ability of teratogens to elevate the embryonic expression of CYP1A1 was examined. Micromass cell cultures prepared from day 13 rat embryo limb buds (LB). LB cells were cultivated and exposed for 5 days to retinoic acid (RA), hydrocortisone (HC), caffeine (CA) and quinine (QN). CYP1A1 protein expression and activity were measured using immunofluorescence staining and ethoxyresorufin O-deethylation (EROD) assay, respectively. The EROD activity increased significantly following LB cells exposure to RA and HC (p<0.05) but the expression of CYP1A1 protein was reduced by these drugs, whereas the expression of CYP1A1 protein and EROD activity decreased significantly following the addition of CA and QN (p<0.05, p<0.01). Our findings show that studied teratogens have potency to increase CYP1A1 activity.

A comparative study of two novel nanosized radiolabeled analogues of methionine for SPECT tumor imaging.

It has been reported that most tumor cells show an increased uptake of variety of amino acids specially methionine when compared with normal cells and amino acid transport is generally increased in malignant transformation. Based on the evidences, two novel nanosized analogues of methionine (Anionic Linear Globular Dendrimer G(2), a biodigredabale anionic linear globular-Methionin, and DTPA-Methionine(1) conjugates) were synthesized and labeled with (99m)Tc and used in tumor imaging/ therapy in vitro and in vivo. The results showed marked tumor SPECT molecular imaging liabilities for both compounds but with a better performance by administration of (99m)Tc-Dendrimer G(2)-Methionin. The results also showed a good anticancer activity for 99mTc-DTPA-Methionine. Based on the present study (99m)Tc-Dendrimer G(2)-Methionin or 99mTc-DTPA-(Methionine)(1) have potentials to be used in tumor molecular imaging as well as cancer therapy in future.

Protective effect of pretreatment with thymoquinone against Aflatoxin B(1) induced liver toxicity in mice.

BACKGROUND AND THE PURPOSE OF THE STUDY: Thymoquinone (TQ) is one of the active components of Nigella sativa. The plant has been used in herbal medicine for treatment of many diseases including liver complications. The present study aimed to investigate protective effects of TQ on Aflatoxin B(1) (AFB(1)) induced liver toxicity in mice. METHODS: Animals were divided into six groups and treated intraperitoneally. Group 1 (blank) served as vehicle, group 2 (positive control) received AFB(1), Group 3 was treated with 9 mg/kg of TQ, Groups 4, 5 and 6 were treated with 4.5, 9 and 18 mg/kg of TQ, respectively. After three consecutive days, except for groups 1 and 3, animals were administered with a single dose of AFB(1) (2 mg/kg). All the animals were killed 24 hrs following the AFB(1) administration under ether anesthesia. Biochemical parameters including AST, ALT and ALP in serum samples and glutathione (GSH) and malondialdehyde (MDA) contents in liver homogenates were determined. Liver sections were collected for histopathological examination. RESULTS: Findings of this study showed that AST, ALT, ALP and MDA levels were significantly lower in the TQ treated animals as compared to AFB(1) group (group 2). Furthermore, TQ was able to recover glutathione content (GSH) of liver tissue. The best response, however, was observed with the dose of 9 mg/kg. Liver sections of AFB(1) intoxicated mice showed inflammation, necrosis, hyperplasia of kupffer and infiltration of mononuclear cells, dilation of sinusoids and disruption of hepatocytes, while treatment with TQ helped to normalize liver architecture in accordance to biochemical findings. CONCLUSION: Taken collectively, TQ has a protective role with optimum dose of 9 mg/kg in AFB(1) hepatotoxicity.

Evaluation of the teratogenicity of fennel essential oil (FEO) on the rat embryo limb buds culture.

The use of FEO as a remedy for control of primary dysmenorrhea increases concern about its potential teratogenicity due to its estrogen-like activity. Limb bud mesenchymal cells, when grown in high-density cultures, can be differentiated into a number of cell types including cartilage and muscle. These cells have been used extensively for in vitro studies of chondrogenesis. Therefore, we used limb bud cells and Alcian blue staining method that is specific for staining cartilage proteoglycan, to determine the teratogenic effect of FEO. Limb bud cells obtained from day 13 rat embryo were cultivated and exposed to various concentrations of FEO for 5 days at 37 degrees C and the number of differentiated foci were counted. Retinoic acid (90 microg/ml) was chosen as positive standard control. The differentiation was also evaluated using limb bud micromass culture using immunocytochemical techniques and BMP-4 antibody. The results showed that FEO at concentration as low as 0.93 mg/ml produced a significant reduction in the number of stained differentiated foci. However, this reduction was due to cell loss, determined by neutral red cell viability assay, rather than to be related to decrease in cell differentiation. These findings suggest that the FEO at the studied concentrations may have toxic effect on fetal cells, but there was no evidence of teratogenicity.

Differentiation of bovine and porcine gelatins using principal component analysis.

Gelatin is a collagen derivative, which has a large application in the pharmaceutical, food and adhesive industries as well as photography. The large similarity in structure and properties of gelatins from different origins makes their differentiation difficult. Certain chemometric methods, such as principal component analysis (PCA), can help to classify and characterize gelatin components. In this study 14 bovine and 5 porcine gelatins were examined. The analysis procedure involved complete hydrolysis of samples by classic acid hydrolysis in order to release their amino acid residues. Separation and determination of amino acids was achieved by reversed-phase (RP) HPLC following pre-column derivatisation. Orthophtaldialdehyde (OPA) and 4-chloro-7-nitro benzofurazane (NBD-Cl) were used as derivatisation reagents. From the 20 peaks detected by HPLC analysis, one was very typical in bovine gelatin. Peak height, area, area percentage and width were used to make matrixes. Principal component analysis with the MATLAB program was used to differentiate these gelatins. PCA on matrix of height, width and total matrix were resulted in good differentiation between bovine and porcine gelatins.

Application of a simple and sensitive GC-MS method for determination of morphine in the hair of opium abusers.

Thirty hair samples were collected from male opioid abusers for whom the presence of morphine in their urine samples was confirmed by thin layer chromatography (TLC). The hair samples were decontaminated by washing with isopropanol, deionized water, and isopropanol, dried at room temperature, and cut into small pieces. Samples of the latter (30 mg ) were digested by incubation in a mixture of methanol-trifluoroacetic acid (9:1) for 18 h at 45 degrees C and sonicated to improve the extraction process. The methanolic phase was evaporated to dryness under a stream of nitrogen at 50 degrees C. The sample was derivatized by addition of N-methyl- N-trimethylsilyltrifluoroacetamide (MSTFA) and 1% trimethyliodosilane (TMIS) at 70 degrees C for 20 min, with sonication. Derivatized samples (1 microL) were injected into a gas chromatograph-mass spectrometer (GC-MS) system fitted with a capillary column; the Finnigan MS was operated in SIM mode. Naltrexone was used as internal standard (IS). The masses of the ions selected for morphine and naltrexone were 429 and 557, respectively. The limit of quantitation was set at 0.03 ng mg(-1) hair. By using the above procedure we detected morphine in all the samples examined, in the concentration range 0.26-10.31 ng mg(-1 )hair.

A retrospective study of poisoning in Tehran.

OBJECTIVE: To examine the causes and mortality of poisoning in Tehran. METHODS: The 7000 poisoning cases referred to Loghman-Hakim Hospital in Tehran over six months in 1994 were evaluated retrospectively. RESULTS: The overall female to male ratio was 1.8:1. Most poisonings occurred in the age range 2-6 y for children and 21-40 y for adults. Oral ingestion was the most common route of intoxication. In children, boys had a higher frequency of poisonings than girls. Most cases of children were referred to the hospital between 8 am and 8 pm. In adults referred to the hospital, there was little diurnal variation in poisoning presentations. In adults, drugs were the most common cause of intoxication (60.2%). Of these, benzodiazepines (24.5%) were the most frequent, followed by antidepressants (20.5%) and analgesics (18%). Pesticide and opiate intoxications were also commonly observed. In children, after drugs (32.1%), hydrocarbons were the most frequent cause of poisoning (19.2%). Pesticide poisonings were most often fatal (19.2%), followed by barbiturates (18.6%) and opiates (16.2%). Organophosphate insecticides were responsible for 57% of total pesticide poisoning cases. Of the deaths, 87.5% were attributed to suicide. CONCLUSION: The majority of poisoning cases in adults occur intentionally and in children accidentally.

Bifonazole, but not the structurally-related clotrimazole, induces both peroxisome proliferation and members of the cytochrome P4504A sub-family in rat liver.

Male Wistar rats were treated with a low (150 mumol/kg) and a high (750 mumol/kg) dose of either clotrimazole of bifonazole. Bifonazole, but not clotrimazole, exhibited the characteristics of a peroxisome proliferator including hepatomegaly (increase in liver:body weight ratio), up to a 4-fold induction of lauric acid omega-hydroxylase activity and an 8-fold induction of palmitoyl-CoA oxidation by rat liver peroxisomes. This induction of enzyme activities was paralleled by increased protein levels as determined by immunochemical analysis for both liver microsomal cytochrome P4504A1 and the peroxisomal trifunctional protein of the beta-oxidation spiral. In contrast, clotrimazole did not increase protein levels of either cytochrome P4504A or the trifunctional protein. Western blot analyses demonstrated that bifonazole also induced P4502B1/2B2, P4503A and P4501A1, but not P4502E1. Clotrimazole induced a similar spectrum of P450s as determined by Western blotting with the exception that this azole was a marginal P4501A1 inducer under the conditions studied. Taken collectively, our data provides evidence that bifonazole is one of the increasingly recognised, non-carboxylate containing xenobiotics that induce both peroxisome proliferation and the cytochrome P4504A sub-family in rat liver.

Comparative induction of cytochrome P4504A in rat hepatocyte culture by the peroxisome proliferators, bifonazole and clofibrate.

1. The influence of imidazole and triazole antifungal drugs on cytochrome P450 levels in male Wistar primary rat hepatocyte culture for 70 h has been investigated and compared with clofibrate. 2. Bifonazole, clotrimazole, geniconazole clofibrate induced total P450 in hepatocytes, whereas itraconazole, miconazole and UK-47,265 did not. 3. When the CYP4A subfamily was examined, only bifonazole and clofibrate induced CYP4A as assessed by both Western blot analysis and the 11- and 12-hydroxylation of lauric acid. 4. By analysis of concentration-response curves in hepatocyte culture, bifonazole was 160 and 40 times more potent than clofibrate for induction of the 11- and 12-hydroxylation of lauric acid respectively. 5. Taken collectively, our data have identified bifonazole as a relatively potent, non-carboxylate inducer of CYP4A and the mechanism of induction and specificity of this azole is discussed.