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Background and Objective: The anthracyclin drug doxorubicin (Adriamycin) is one of the most effective antineoplastic agents, and widely used to treat a number of malignancies. However, its use has been restricted due to the dose-dependent cardiotoxicity. The mechanisms of Doxorubicin - induced cardiotoxicity is not entirely clear. This study investigates the effect of Doxorubicin on Bcl2 and Bax genes expression as key molecules that involve in intrinsic pathway of apoptosis in rat heart. Materials and Methods: In this experimental study Doxorubicin administration, male Wistar rats were exposed to intraperitoneal injections (2.5 mg/kg, six times for 2 weeks, n=20). Animals were randomly assigned to the healthy untreated control (n=10) and to the Doxorubicin treatment groups (n=10). Three weeks after completion of treatment myocardial fibrosis, Bcl2 and Bax genes expression were investigated by Masson’s trichrome staining and Real Time- PCR analysis respectively. Statistical analysis was performed using the SPSS-16 and independent samples t-test, Mann-Whitney and Kaplan-Meyer method. Results: Masson’s trichrome staining showed that Doxorubicin increased fibrosis in the cardiac muscle (16.4±1) in compare to control group (1±0.79). Real Time- PCR analysis showed that Doxorubicin decreased Bcl2 expression levels (0.1±0.07) and increased Bax expression levels (2.1±0.1) in the myocardium in compare to control group (P<0.01). Conclusion: This study showed that administration of Doxorubicin increase interstitial fibrosis of myocardium and Bax expression levels and decrease Bcl2 expression that are the key genes of mitochondria-dependent apoptotic pathway.

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Background and Objective: Aspartame is a kind of artifical and non-sugar sweetener that is used as a sugar substitute in some foods and beverages. This study was done to determine effect of Aspartam on histomorphometric alterations, kidney function and expression of Bcl2, Bax, Caspase 3, P53 Genes in Mice.
Methods: In this experimental study, 36 adult male NMRI mice were allocated into four groups including control group and three experimental groups. The mice in the control group received 0.3 ml of distilled water by oral gavage for 90 days and the experimental groups received 40, 80 and 160 mg/kg aspartame, respectively orally and daily. One day after treatment, blood and kidney tissue samples were taken to evaluate biochemical, histomorphometric alterations and gene expression.
Results: Renal capsule diameter, glomerulus diameter and height of the epithelial layer of distal and proximal tubules were significantly reduced in treated groups compared to control group with increasing dosage of aspartame (P<0.05). However, the size of the urinary space and the diameter of the lumen of distal and proximal tubules were significantly increased in treated groups in compared to control group (P<0.05). The level of blood nitrogen urea (BUN) and creatinine significantly increased treated groups in compared to the control group with increasing dosage of aspartame (P<0.05). Also, with increasing dosage of aspartame, Bcl2 gene expression significantly reduced in treated groups in compared to the control group (P<0.05) however expression of Bax, Caspase 3 and p53 genes were significantly increased in treated groups compared to the control group (P<0.05).
Conclusion: Aspartame can cause changes in biochemical, histomorphometric indices, expression of Bcl2, Bax, Caspase 3 and P53 genes in mice kidney.