Based on the rapid hydrolysis of acetyl salicylic acid (ASA, Aspirin) to salicylic acid (SA), the ability of SA to form dihydroxy benzoic acid (DBA), and the latter’s redox reactions to yield hydrogen peroxide (H2O2), we predicted that ASA may have the potential to induce Sirtuin1 (Sirt1) and its downstream effects. We observed that treatment of cultured liver cells with ASA resulted in the induction of Sirt1, peroxisome proliferator-activated receptor-gamma co-activator-1α (PGC-1α), and NAD(P)H quinone oxidoreductase 1 (Nqo1) genes. Paraoxonase 1 (PON1) and Aryl hydrocarbon receptor (AhR) siRNA transfections inhibited the induction of gene expressions by ASA suggesting the need for the acetyl ester hydrolysis and hydroxylation to DHBA. The latter also induced Sirt1, confirming the proposed pathway. As predicted, ASA and SA treatment resulted in the production of H2O2, a known inducer of Sirt1 and confirmed in the current studies. More importantly, ASA treatment resulted in an increase in mitochondria as seen by tracking dyes. We suggest that DHBA, generated from ASA, via its oxidation/reduction reactions mediated by Nqo1 might be involved in the production of O2-. and H2O2. As Sirt1 and PGC-1α profoundly affect mitochondrial metabolism and energy utilization, ASA may have therapeutic potential beyond its ability to inhibit cyclooxygenases.

In our previous findings, we have demonstrated that aspirin/acetyl salicylic acid (ASA) might induce sirtuins via aryl hydrocarbon receptor (Ah receptor). Induction effects included an increase in cellular paraoxonase 1 (PON1) activity and apolipoprotein A1 (ApoA1) gene expression. As predicted, ASA and salicylic acid (SA) treatment resulted in generation of H2O2, which is known to be an inducer of mitochondrial gene Sirt4 and other downstream target genes of Sirt1. Our current mass spectroscopic studies further confirm the metabolism of the drugs ASA and SA. Our studies show that HepG2 cells readily converted ASA to SA, which was then metabolized to 2,3-DHBA. HepG2 cells transfected with aryl hydrocarbon receptor siRNA upon treatment with SA showed the absence of a DHBA peak as measured by LC-MS/MS. MS studies for Sirt1 action also showed a peak at 180.9 m/z for the deacetylated and chlorinated product formed from N-acetyl Lε-lysine. Thus an increase in Sirt4, Nrf2, Tfam, UCP1, eNOS, HO1 and STAT3 genes could profoundly affect mitochondrial function, cholesterol homeostasis, and fatty acid oxidation, suggesting that ASA could be beneficial beyond simply its ability to inhibit cyclooxygenase.

Materials and Methods Animals and ethical clearanceAdult male albino rats of Wistar strain were used for the study. Animals were weighing about 220-250g obtained from Rajudyog biotechnology division Maharashtra, India were used. The animal studies were carried out upon institutional animal ethical committee approval. DrugsEtoposide was procured from Dabur India Ltd. Bovine serum albumin, reduced and oxidized GSH, thio barbituaric acid (TBA), butylated hydroxytolune (BHT), L-gammaglutamyl-p-nitroanilidehydrochloride, sodium azide, Dinitro thio benzoic acid (DNTB), NADPH, sodium dithionite, sodium formate were purchased from SRL India. All other chemicals used were of analytical grade. MethodologyAnimals were acclimatized for a period of two-weeks and were then treated. They received standard pellet and water ad libitum. Rats

Background:Cisplatin is well-known anticancer drug often been used for treatment of various human malignancies. The hepatotoxic or nephrotoxic effect of drug is a result of altered histological and antioxidant status of the organ. In order to document the extent of cisplatin (CDDP) effect on liver we have studied long term treatment of cisplatin (CDDP) to rat. In our previous studies we have demonstrated changes in reduced glutathione (GSH) and glutathione related enzymes of liver followed by increased lipid peroxidation process. Materials: Light microscopy (LM) was carried out in liver tissue by haematoxylin and eosin staining. Electron microscopy was performed by staining with uranil acetate and lead citrate. Results: Recent reports depicts that CDDP treatment caused significant alteration at histopathological level showing increased vacuolation in hepatocytes. A noticeable change observed after drug treatment is large perilobular connective and expanded portal spaces. Morphological alterations after transmission electron microscopy (TEM) showed heterochromatic border in nucleus followed by prescence of large agglutinations of lysosomes, numerous rough endoplasmic reticulum (RER) and mitochondria has been observed as one of the significant effect of drug. Conclusion: Thus cytoarchitectural studies signify that long term of CDDP intervention at 0.4 mg/kg/day/animal caused least damage to liver.

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