Ellagic acid is described as having antioxidant and antiproliferative properties. Hence, it was hypothesized that ellagic acid could improve cardiovascular damage caused by hypertension. In this work, hypertension was induced in rats with N-Nitro-L-arginine methyl ester hydrochloride (60 mg/kg/day in drinking water) for 6 weeks. Ellagic acid was coadministered (10 or 30 mg/kg/day by gavage) between the second and sixth week. Blood pressure was recorded every week by tail-cuff plethysmography. After 6 weeks, the rats were sacrificed, the hearts and kidneys were weighed, and blood was collected. Aortas were isolated and set up to isometric recordings in an organ bath for histological assay and measuring of calcium content. Hypertension (233.6 ± 9.5 mmHg) was reduced (p < 0.01) by treatment with ellagic acid 10 or 30 mg/kg. The blood levels of nitrate/nitrite were reduced in hypertensive rats and the ellagic acid restored these levels. While the vascular relaxations to acetylcholine and sodium nitoprusside and the contraction to phenylephrine were impaired in the hypertensive group, they were improved after ellagic acid treatment. The alkaline phosphatase activity was increased by hypertension and returned to control levels after ellagic acid treatment. In the aorta, the administration of ellagic acid resulted in less aortic wall thickening and less calcification. In conclusion, ellagic acid attenuates hypertension, possibly improving nitric oxide bioavailability. The vascular response to acetylcholine, sodium nitroprusside, and phenylephrine was impaired by hypertension and improved after treatment with ellagic acid. Moreover, plasmatic alkaline phosphatase activity, calcium content, and hypertrophy in vascular tissues during hypertension were attenuated by treatment with ellagic acid.

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Leukemia is a major type of cancer affecting a significant segment of the population, and especially children. In fact, leukemia is the most frequent childhood cancer, with 26 % of all cases, and 20 % mortality. The multidrug resistance phenotype (MDR) is considered one of the major causes of failure in cancer chemotherapy. The present study aimed to investigate the relationship between the expression of MDR1 and CYP450 genes in human chronic myelogenous leukemia cells (K-562) treated with cisplatin (cisPt) and two ruthenium-based coordinated complexes [cisCRu(III) and cisDRu(III)]. The tested compounds induced apoptosis in K-562 tumor cells as evidenced by caspase 3 activation. Results also revealed that the amplification of P-gp gene is greater in K-562 cells exposed to cisPt and cisCRu(III) than cisDRu(III). Taken together, all these results strongly demonstrate that MDR-1 overexpression in K-562 cells could be associated to a MDR phenotype, and moreover, it is also contributing to the platinum and structurally related compound, resistance in these cells.

Lung cancer is one of the leading causes of death in the world, and non-small cell lung carcinoma (NSCLC) accounts for approximately 75-85% of all lung cancers. In the present work, we studied the cytotoxic activity, cell cycle arrest and induction apoptosis of the compound cis-(dichloro)tetramineruthenium(III) chloride {cis-[RuCl(2)(NH(3))(4)]Cl} in human lung carcinoma tumor cell line A549. The results of MTT and trypan blue assays showed that cis-[RuCl(2)(NH(3))(4)]Cl causes reduction in the viability of A549 cells when treating with 95 and 383 μM of the compound for 48 and 72 h. Lower concentrations of the compound (19, 3.8 and 0.38 μM), however, only slightly affected cell viability. The IC(50) value for the compound was about 383 μM. Survival analysis of the A549 cells after treatment with ruthenium(III) compound using long term clonogenic assay showed that it reduced colony formation ability at concentrations of 0.38 and 3.8 μM, and at concentrations of 95 and 383 μM no colonies were observed. Cell cycle analysis showed that compound ruthenium led to an accumulation of A549 cells in S phase and increased in the sub-G1 peak. In addition, cis-(dichloro)tetramineruthenium(III) chloride treatment induced apoptosis, as observed by the increased numbers of annexin V-positive cells and increased messenger RNA expression of caspase-3.