The genotoxicity study of resveratrol in primary gastric adenocarcinoma cell cultures.

Gastric cancer is the second most common cause of cancer-related death in the world. Some studies indicate that polyphenolic compounds and antioxidants exert a protective action against gastric cancer. Among the polyphenolic compounds tested and proven effective against gastric cancer is resveratrol, a natural polyphenol present in red wines and various human food items. Resveratrol has been shown to suppress proliferation of a wide variety of tumor cells. We tested the genotoxic activity of resveratrol in primary cell cultures from gastric adenocarcinoma, obtained by mucosal biopsy at upper digestive endoscopy. The adenocarcinoma cells were analyzed for the presence of micronuclei at different concentrations of resveratrol at 48 hours and at 72 hours. The results showed that resveratrol induced micronuclei dose-dependently. The frequency of micronuclei increased progressively with the dose of resveratrol used, the high frequency is in the primary culture initiated from gastric adenocarcinoma: signet ring cell type. The high frequency of micronuclei is at 72 hours at the 20 microg/mL resveratrol and is decreased at low concentrations (5 microg/mL, 10 microg/mL resveratrol). This results show the genotoxic activity of resveratrol in adenocarcinoma gastric cell and the anticancer property of this substance.

Comparative effects of boric acid and calcium fructoborate on breast cancer cells.

Recent studies suggested that boron has a chemo-preventive role in prostate cancer. In the present report, we investigated the effects of calcium fructoborate (CF) and boric acid (BA) on activation of the apoptotic pathway in MDA-MB-231 human breast cancer cells. Exposure to BA and CF inhibited the proliferation of breast cancer cells in a dose-dependent manner. Treatment with CF but not BA resulted in a decrease in p53 and bcl-2 protein levels. Furthermore, after the treatment with CF, augmentation of pro-caspase-3 protein expression, cytosolic cytochrome c level, and caspase-3 activity were observed, indicating apoptotic cell death induction. This was also demonstrated by terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick-end-labeling assay. In conclusion, our data provide arguments to the fact that both BA and CF inhibited the growth of breast cancer cells, while only CF induced apoptosis. Additional studies will be needed to identify the underlying mechanism responsible for the observed cellular responses to these compounds and to determine if BA and CF may be further evaluated as chemotherapeutic agents for human cancer.

In vitro effects of calcium fructoborate on fMLP-stimulated human neutrophil granulocytes.

Discovery of naturally occurring boron complexes with organic compounds containing hydroxyl groups, sugars, and polysaccharides, adenosine-5-phosphate, pyridoxine, riboflavin, dehydroascorbic acid, and pyridine nucleotides led to the reassessment of the biochemical role of boron. Boron's anti-inflammatory actions were claimed but not yet demonstrated. This study investigated the effects of calcium fructoborate (CF) on the human polymorphonuclear neutrophils (PMN) that play a central role in the inflammatory response. Our results demonstrated that CF exposure induced a dose-dependent decrease in cell viability. Treatment of PMN cells, for 24 h, with 22,500 microM CF led to a decrease in cell viability by 61.1%, an inhibition of respiratory burst by 92.9% in the case of fMLP-stimulated cells, a diminution of intracellular level of superoxide anion with 59.3%, and a stimulation of superoxide dismutase activity by 72% in unstimulated PMN cells. Altogether, these results suggest the antioxidant and anti-inflammatory properties of CF.

Boron enhances the thermostability of carbohydrates.

We have studied the effect of borate and pH upon the half-lives of ribose and glucose. Under acidic conditions the presence of boric acid increase the thermo-stability of ribose, while under basic conditions glucose is favored.

In vitro evaluation of the antioxidant activity of calcium fructoborate.

Although increasing evidence shows the nutritional benefits of calcium fructoborate (CF) on animals and humans, its action mechanism has not been clearly identified. The present study aims to investigate the possible antioxidant function of CF. Based on its efficiency in skin wound healing, the authors tested whether CF possesses antioxidant properties on human keratinocytes cultures, in a complete serum-free medium (KMK-2; Sigma). The cells treated with CF (0-450 nmol/culture medium) were exposed to exogenous 100 micromol of hydrogen peroxide to mimic the oxidative stress. The changes in general cell oxidant production evaluated with dihydrorhodamine-123 showed that the intracellular reactive oxygen species (ROS) were markedly reduced by preincubation with CF. The maximum antioxidant activity was noticed at 90 nmol CF. To assess the reactivity of CF on ROS, we analyzed its ability to inhibit the superoxide- dependent auto-oxidation of pyrogallol. The CF inhibited the pyrogallol auto-oxidation depending on time and concentration, which suggests its possible role as a superoxide radical scavenger. Taken together, our results indicate that CF has antioxidant activity, which could have clinical significance in protecting cells from oxidant-induced injury. A hypothetic mechanism for the antioxidant activity of CF is proposed.

Stable reconstruction of the T(2) distribution by low-resolution NMR measurements and the classical markov and hausdorf momentum problem

Assuming that an original distribution is a probabilistic measure and the Laplace transforms are known only for a finite number of points that are affected by errors, we develop a method for reconstructing weak-sense mean values obtained by integrating smooth functions with the measure. Our method is useful in NMR if the NMR signal can be represented as a superposition of exponential terms. In these circumstances, we show how the data processing can be related to the classical Hausdorf momentum problem. First, we clarify the meaning of stable spectrum reconstruction, and then develop stable filtering and a mean value reconstruction algorithm. Our method has been tested on both simulated and real sets of spin-spin relaxation curves with noise. In view of this, our method could provide an efficient and accurate reconstruction of spin-spin relaxation data. For any reader interested in applications, a "practical recipe" that is almost self-consistent has been included. Copyright 2000 Academic Press.