Journal of School of Public Health and

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Background and Aim: In order to elucidate the role of vitamin D in the genesis of lung tumors, we used an experimental model of lung lesions in mice induced by the administration of urethane.
Materials and Methods: A total of inbred balb/c mice (male and female) 9-11 weeks old, were studied. They were divided into 3 groups. The first and second groups (U and U+D) were injected with urethane i.p, 600 mg/kg/day with 48 hours intervals for three times. The second group was given 3.5 mg/kg (6.3 mg/1000 ml) vitamin D with drinking water for 4 weeks after starting the injection by urethane.
Results: The third group served as control. Total remaining mice were killed after 20 weeks. Lung lesions were histopathologically characterized by hyperplasia, adenoma and adenocarcinoma in different groups. Tumor formation significantly increased in the urethane group as compared with control group (p<0.05) but there was not any difference between those receiving the (U+D) treatment group and the controls.
Conclusion: It seems vitamin D inhibites genesis of lung tamors induced by the administration of urethane.

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Background and Aim: To determin the most sensitive tissues to carcinogenic effect of urethane and co-carcinogenic effect of sodium nitrite by investigation of histopathological variations in different tissues of balb/c mice.

Materials and Methods: An experimental study in 40 inbred balb/c mice aged 9-11 weeks was designed. The samples were classified into 4 groups: The first group was mice treated with 50 mg/l sodium nitrite in 0.9% NaCl instead drinking water SN&NaCl). The urethane group (U) was characterized by intraperitoneal injection of 3 times urethane (600 mg/ kg/day at 48 hour intervals). The third group was given 50 mg/l sodum nitrite in drinking water (U&SN) following the same intake of urethane as the second group, and the forth one was the control group. All mice were sacrificed after 20 weeks tissues were removed and examined for histopathological changes. Data analyzed by Fisher exact test.

Results: The formation of lung tumor was, significantly, increased in the urethane group as compared with the control group & (NS+Nacl) groups ( respectively P<.004 & P<.02) and in (U+NS) group as compared with the control group & (NS+Nacl) groups ( respectively P<.003 & P<.02). In females mice also The formation of lung tumor was, significantly, increased in the urethane group as compared with the control group & (NS+NaCl) groups (P<.05) and in the (U+NS) group was significantly higher than those in (C) & (NS+NaCl) groups (P<.009). The formation of lung adenocarcinomas was, significantly, increased in the (U+NS) group as compaired with the (C) & (NS+Nacl) groups (P<.003). In females mice also the formation of lung adenocarcinomas was, significantly, increased in the (U+NS) group as compaired with the (C) & (NS+Nacl) groups (P<.009) and (U) group (p<.05).The frequencies of stomach and testis hyperplasia and metaplasia in different groups did not show any significant differences. There was no histopathological variation in other tissues.

Conclusion: Our results showed the tumorigenic effect of urethane in lung tissue. Sodium nitrite increases tumorogenic effect of urethan. Sodium nitrite increases carcinogenic effect of urethan (This result is the first study that suggest sodium nitrite increases carcinogenic effect of urethan).Urethan increases co-carcinogenic effect of sodium nitrite.

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Background and Aim: The normal plasma fatty acid (FA) composition changes in hypertriglyceridemic obese and overweight indiuviduals. The objective of this study was to determine the plasma fatty acid composition in hypertriglyceridemic obese or overweight subjects with different FABP2 genotypes.

Methods and Materials: Forty-six hypertriglyceridemic subjects (33 men and 13 women, 25-60 years old) referred to the Endocrinology and Metabolism Research Center (EMRC), Shariaty Hospital in Thehran, between Mehr and Esfand 1386 (September 2007-March 2008), were genotyped for FABP2 polymorphism by PCR-RFLP. In addition, their blood lipid profile was determind enzymetically, photometrically and immunoturbidometrically, and their plasma fatty acid composition by gas-choromatography. Also, body weights and heights were measured and body mass index calculated.

Results: Positive associations were observed between Thr54 polymorphism in FABP2 protein and plasma lipid fractions (SFA, PUFA, ω-6-, ω-3- and total fatty acids (P<0.001 )). No significant differences were observed between PPARα polymorphism and plasma fatty acid composition, except for ω-3 fatty acids,

Conclusion: In obese or overweight hypertriglyceridemic subjects the plasma fatty acid compositions are different. The levels of some fatty acids are higher, while those of some others are lower, in different FABP2 genotypes. On the whole, higher levels of SFA, PUFA, ω-6, ω-3, and total fatty acids were more pronounced in Thr54- than in Ala54-carrieres.