Seite - (000151) - in Biomedical Chemistry: Current Trends and Developments

a high bicarbonate to sodium ratio (1 L day-1, 8 weeks), reduced systolic blood pressure (an effect already seen after 4 weeks), apolipoprotein-B, total-cholesterol and LDL-cholesterol fasting serum levels as well as total-cholesterol and LDL-cholesterol to HDL-cholesterol ratios (Perez- Granados, 2010). The same group showed, in healthy postmenopausal women, that a) the ingestion of the previous water (1 L day-1, 2 months) increased HDL-cholesterol and decreased endothelial dysfunction markers, glucose, total-cholesterol and LDLcholesterol fasting serum levels as well as total-cholesterol and LDL-cholesterol to HDL- cholesterol ratios (Schoppen, 2004), and b) the consumption of sodium- rich bicarbonated mineral waters (0.5 L each) with a standard fat-rich meal increased insulin sensitivity [more distinctly in the women with higher homeostasis model assessment (HOMA) index values] and decreased lipemia (Schoppen, 2005; Schoppen, 2007). Both a decrease in lipid and protein oxidation products and an increment of total antioxidant capacity and total thiol plasma levels were observed in healthy individuals drinking a sulfurous mineral water (0.5 L day-1, 2 weeks) (Benedetti, 2009). Our group evaluated the effects of the ingestion of a Portuguese natural mineral-rich water, and some of the possible mechanisms involved, on metabolic function in a well-validated MetSyn animal model (Polizio, 2006; Rayssiguier, 2006; Oron-Herman, 2008): male Sprague-Dawley rats treated with 10% fructose in drinking water, for 8 weeks. Animals were randomly assigned into three groups with free access to food and a) tap water, b) 10% fructose in tap water or c) 10% fructose in Portuguese natural mineral-rich water. As expected, 10% fructose in tap water induced metabolic features characteristic of the MetSyn, such as increased plasma levels of triglycerides, insulin and leptin [with a strong tendency toward decreased insulin sensitivity index (Cacho, 2008)] and decreased plasma levels of magnesium as well as increased systolic blood pressure and heart rate. Fructose-induced effects in the redox state (liver), endoplasmic reticulum homeostasis (liver), glucocorticoid and insulin signalling pathways (liver and visceral and/or subcutaneous adipose tissue) and endothelial dysfunction markers expression (cavernous tissue) may have contributed to explain the induction of MetSyn; some compensatory mechanisms against