Effect of training on bone quality in rats with insulin resistance induce by fluoride consumption.

When large amounts of Fluoride are consumed produces insulin resistance, but exercise can reverse insulin resistance in rats, because of a high fluoride uptake by bone tissue. However, bone quality has not been studied in those experiments. Therefore, the aim of this work was to evaluate bone quality in rats treated with fluoride when performing exercise.

The combined treatment of insulin and naringin improves bone properties in rats with type 1 diabetes mellitus.

We have studied the effects of individual and combined treatment of insulin (I) and naringin (NAR) on the bone structure and biomechanical properties of femurs from streptozotocin (STZ)-induced diabetic rats. Male Wistar rats were divided into five groups: (1) controls, (2) STZ-induced diabetic rats, (3) STZ-induced diabetic rats treated with I, (4) STZ-induced diabetic rats treated with NAR, and (5) STZ-induced diabetic rats treated with I + NAR. Bone mineral density (BMD), bone histomorphometry, biomechanical testing, and bone biomarker expressions were accomplished in femur of all animals, as well as serum biochemical analyses.

Naringin prevents bone damage in the experimental metabolic syndrome induced by a fructose-rich diet.

We analyzed the effect of naringin (NAR), a flavonoid from citric fruits, on bone quality and biomechanical properties, as well as the redox state of bone marrow in rats fed a fructose-rich diet (FRD), an experimental model to mimic human metabolic syndrome. NAR blocked the increase in the number of osteoclasts and adipocytes and the decrease in the number of osteocytes and osteocalcin (+) cells caused by FRD. Trabecular number was significantly higher in the FRD+NAR group.

Effect of fluoride on bone and growth plate cartilage.

The use of fluoride (F) for therapeutic purposes is controversial and its toxicity is a health problem. The aim of this study was to evaluate the effect of F on endochondral ossification in growing rats. Twenty-four rats of 21 days were divided into 4 groups which received 0, 20, 40 or 80 μmol F/100 g body weight/day for 30 days, through an orogastric tube.

Contribution of calcium in drinking water from a South American country to dietary calcium intake.

Objective: To describe the calcium concentration of tap and bottled waters from Argentina and to estimate the contribution of drinking water to calcium recommendations.

Results: Calcium concentrations provided by water authorities ranged from 6 to 105 mg/L. The mean calcium level of samples analysed at the Laboratorio de Ingeniería Sanitaria, National University of La Plata was 15.

Bone Strength in Growing Rats Treated with Fluoride: a Multi-dose Histomorphometric, Biomechanical and Densitometric Study.

Bone deformation and fragility are common signs of skeletal fluorosis. Disorganisation of bone tissue and presence of inflammatory foci were observed after fluoride (F) administration. Most information about F effects on bone has been obtained in adult individuals.

In vivo measurement of the rate constant of liver handling of glucose and glucose uptake by insulin-dependent tissues, using a mathematical model for glucose homeostasis in diabetic rats.

Diabetes mellitus is a disease that affects glucose homeostasis. The World Health Organization informs that there are over 347 million people in the world with diabetes. The diagnosis and characterization of glucose homeostasis in different metabolic conditions are subjects of great importance with high clinical impact.

Assessment of the SWAT model to simulate a watershed with limited available data in the Pampas region, Argentina.

Argentina has been among the world leaders in the production and export of agricultural products since the 1990s. The Carcarañá River Lower Basin (CRLB), a cropland of the Pampas region supplied by extensive rainfall, is located in an area with few streamgauging and other hydrologic/water-quality stations. Therefore, limited hydrologic data are available resulting in limited water-resources assessment.

Comparison of fluoride effects on germination and growth of Zea mays, Glycine max and Sorghum vulgare.

Background: Fluorosis is a disease caused by over-exposure to fluoride (F). Argentina's rural lands have higher fluorine content than urban lands. Evidence confirms that plants grown in fluoridated areas could have higher F content.

Effects of Yerba Mate (IIex paraguariensis) on Histomorphometry, Biomechanics, and Densitometry on Bones in the Rat.

Yerba mate (Ilex paraguariensis) is a xanthine-containing beverage, which is also rich in caffeine. Because caffeine has a negative impact on bone mineral density (BMD) mainly associated with low calcium (Ca) diets, there would be expected a negative effect of yerba mate on bone. In this study, Sprague-Dawley rats were used and randomly assigned into four groups (n = 6/group): Control + Ca 0.

Proteomic analysis of gastrocnemius muscle in rats with streptozotocin-induced diabetes and chronically exposed to fluoride.

Administration of high doses of fluoride (F) can alter glucose homeostasis and lead to insulin resistance (IR). This study determined the profile of protein expression in the gastrocnemius muscle of rats with streptozotocin-induced diabetes that were chronically exposed to F. Male Wistar rats (60 days old) were randomly distributed into two groups of 18 animals.

Fluoride increases superoxide production and impairs the respiratory chain in ROS 17/2.8 osteoblastic cells.

It is known that fluoride produces oxidative stress. Inflammation in bone tissue and an impairment of the respiratory chain of liver have been described in treatments with fluoride. Whether the impairment of the respiratory chain and oxidative stress are related is not known.

Regulation of intestinal calcium absorption by luminal calcium content: role of intestinal alkaline phosphatase.

Scope: Intestinal alkaline phosphatase is a brush border enzyme that is stimulated by calcium. Inhibition of intestinal alkaline phosphatase increases intestinal calcium absorption. We hypothesized that intestinal alkaline phosphatase acts as a minute-to-minute regulatory mechanism of calcium entry.

Methodology developed for the simultaneous measurement of bone formation and bone resorption in rats based on the pharmacokinetics of fluoride.

This paper describes a novel methodology for the simultaneous estimation of bone formation (BF) and resorption (BR) in rats using fluoride as a nonradioactive bone-seeker ion. The pharmacokinetics of flouride have been extensively studied in rats; its constants have all been characterized. This knowledge was the cornerstone for the underlying mathematical model that we used to measure bone fluoride uptake and elimination rate after a dose of fluoride.

Mathematical model of glucose-insulin homeostasis in healthy rats.

According to the World Health Organization there are over 220 million people in the world with diabetes and 3.4 million people died in 2004 as a consequence of this pathology. Development of an artificial pancreas would allow to restore control of blood glucose by coupling an infusion pump to a continuous glucose sensor in the blood.

Physical exercise ameliorates the toxic effect of fluoride on the insulin-glucose system.

Daily intake of water with fluoride concentrations >1.5 mg/l produces insulin resistance (IR). On the other hand, physical activity increases insulin sensitivity in the muscle.

Chicken eggshell as suitable calcium source at home.

Aim: Taken into consideration that the deficiency of calcium (Ca) in the diet is a common problem, the aim of this work was to study the chicken eggshell as Ca source at home. It was evaluated: (1) different mechanisms to process eggshells and find an easy way to determine the required amount of Ca at home and; (2) the flavor and the texture for eggshell fortified food.

Methods: Chemical and mechanical methods of eggshell processing were evaluated.

Luminal calcium concentration controls intestinal calcium absorption by modification of intestinal alkaline phosphatase activity.

Intestinal alkaline phosphatase (IAP) is a brush-border phosphomonoesterase. Its location suggests an involvement in the uptake of nutrients, but its role has not yet been defined. IAP expression parallels that of other proteins involved in Ca absorption under vitamin D stimulation.

Effect of the treatment with monofluorophosphate on survival and tissular damage in rats with pancreatitis.

Background: Monofluorophosphate (MFP) binds to plasma alpha-macroglobulins modifying their structure and antiproteasic activity. The latter is required during pancreatitis, when proteinases are released by the damaged tissue. Previously, it was demonstrated that the treatment with MFP increases the survival of.

Effect of fluoridated water on plasma insulin levels and glucose homeostasis in rats with renal deficiency.

Glucose intolerance in fluorosis areas and when fluoride is administered for the treatment of osteoporosis has been reported. Controlled fluoridation of drinking water is regarded as a safe and effective measure to control dental caries. However, the effect on glucose homeostasis was not studied so far.

Effect of rhGH on the synthesis and secretion of VLDL to lymph and plasma from the intestine of the female rat.

The intravenous administration of rhGH (recombinant human Growth Hormone) to fasting female rats causes an increase in the rate of synthesis and secretion of VLDL (very low density lipoproteins). This phenomenon has three striking characteristics: (1) the demonstration of an unexpected lipogenic effect of rhGH, (2) its rapid occurrence after intravenous injection of the hormone and (3) the apparent dependence on the levels of circulating estrogens, as deduced by the lack of effect of rhGH on males and castrated females. The target tissue for the lipogenic effect was traced to the intestine by means of perfusion experiments of isolated duodenal loops.

Growth-associated changes in the periodontal bone and molar teeth of male rats.

Here we report quantitative data associating periodontal bone variables of young conventional rats with the growth process. The hemimandibles of male rats (IIM/Fm stock, 2 to 15 wk of age.) were excised and submitted to conventional morphologic, radiologic, and histologic evaluation.

Aggregation and inhibition of rat intestinal alkaline phosphatase by high concentrations of calcium. Reversibility of the processes.

Intestinal alkaline phosphatase (IAP) is an enzyme of the brush border of the enterocyte. The activity of IAP biphasically depends on calcium. Although calcium increases IAP activity, when calcium is higher than 20 mmole/L, IAP activity decreases and the amount of an aggregated form increases.