In the livers mefenamic acid ibuprofen and
In the livers, mefenamic acid, ibuprofen, and meloxicam significantly reduced expression of both 20-HETE and EETs synthesizing cyp450 genes (ANOVA, p value <0.05), while diclofenac did not show any significant change (Fig. 5). The strongest effect was observed with ibuprofen treatment, which exhibited a down regulation of cyp2a12, cyp1a2 and cyp2c29 expression by 6.2, 5.5 and 8.6 fold, respectively, compared with the control group.
Regarding the gene expression of ARA metabolizing aloxs, we observed a slight induction of alox12 and 15 in the liver and kidney samples of NSAID treated mice compared with the control group. However, this elevation was not significantly different (p value > 0.05, Fig. 6).
Control group: The lobular architecture and zonal accentuation in the liver of the control group were well preserved and kept intact and demonstrated normal hepatocytes, sinusoids and hepatic portal triads (Fig. 7A). The histological picture of both cortex and medulla of the control kidneys showed normal glomeruli together with normal proximal and distal renal tubules (Fig. 7B). Loops of Henle and the collecting tubules also appeared normal. Moreover, the heart of the control mice demonstrated normal histological architecture of myocardial fibers with oval nuclei, arranged as bundles parallel to each other and separated by connective tissue which contains blood capillaries (Fig. 7C).
Mefenamic acid-treated group: In comparison with the control group, the liver of mefenamic acid-treated mice demonstrated hepatocytes hydropic degeneration, sinusoidal dilatation, Kupffer cells hyperplasia, pyknotic mitotic figures, apoptotic hepatocytes, bile duct hyperplasia, and occasional fatty change (Figs. 7D-I). In addition, the renal tissues of the mice treated with mefenamic faah inhibitor for 14 days demonstrated glomerular atrophy, glomerular congestion, renal tubular hydropic degeneration, moderate collecting tubules degeneration, tubular vacuolization and renal cells karyopyknosis (Figs. 7M-P). Moreover, the myocardial fibers of the mice subjected to mefenamic acid showed focal wavy appearance, ballooning, necrosis, cardiac disarray, cytoplasm vacuolization together with occasional dilation and congestion of blood capillaries (Fig. 7Q-S). In addition, cardiomyocytes exhibited-pyknotic and irregular nuclei with edema and hyaline degeneration (Fig. 7R–S).
Discussion Disturbance of ARA-p450 genes was found as a mechanism of drug-induced cardiotoxicity. Since many studies reported the cardiovascular events induced by the most commonly used NSAID administration [, , ], we assumed these NSAIDs disturb expression of ARA-p450 genes. In this study, we showed for the first time that NSAIDs altered the expression of ARA-cyp450 genes in the heart, kidneys and liver of treated mice, and these alterations were associated with decreased expression of the cardio-protective biomarker gene GATA4 and increased cox2 expression in the heart. The molecular findings resulted from mefenamic acid administration were in line with the histological alterations induced by the drug in the tested organs. These results can increase our understanding of the mechanism involved in the disturbance of cardiovascular homeostasis induced by NSAID treatment. Aghazadeh-Habashi et al. showed that some NSAIDs, such as rofecoxib and meloxicam, changed the levels of ARA-cyp450 metabolites in treated rats . They showed that the ratio of 20-HETE to EETs was increased in the heart and was decreased in the kidney. However, the exact mechanism of how those NSAIDs altered ARA-cyp450 s was not investigated. The present study investigated the effects of the NSAIDs diclofenac, mefenamic acid, ibuprofen and meloxicam on expression of ARA-metabolizing cyp450 genes in order to identify the mechanism of how NSAIDs affect ARA-cyp450 genes. Our results agree with Aghazadeh-Habashi et al. , reporting that, compared with the control group, 20-HETE synthesizing gene cyp4a12 was highly upregulated (> 2 fold) in the heart, while it was downregulated (> -2 fold) in the kidney in parallel to cyp1a2 expression. Furthermore, the EET synthesizing gene cyp2c29 was significantly upregulated (p-value < 0.05) in the kidney. These alterations can be speculated as 20-HETE synthesis is increased in the heart while it is decreased in the kidney, and EETs synthesis is increased in the kidney. Therefore, the disturbance of ARA-cyp450 metabolites by NSAIDs observed in the previous studies can be explained, at least in part, through alterations in the gene expression of 20-HETE and EETs synthesizing enzymes.