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Tungsten compositions have shown success as part of the oral treatment of diabetes mellitus. It is used in our formula to help in the production of active insulin and prevent diabetic type II formations. Tungsten is a part of insulin molecules similar to chromium & vanadium. Please see more in our Clinical Studies below.
Clinical Studies
The cytotoxic effects of tungstate1
These effects were checked in primary cultured rat hepatocytes. The hepatocytes were isolated by collagenase digestion. Four rats were used to perform these experiments, after the hepatocytes were allowed to attach to the collagen-coated dishes and differentiate, the cells were incubated for 24 hours with different doses of tungstate (0.01, 0.1 and 1 mM). The toxicity of tungstate was evaluated by the release of a cytosolic enzyme to the extracellular medium, since when the cells die their intracellular content is released. The cytosolic enzyme activity measured was lactate dehydrogenase (LDH). The activity of this enzyme was determined by spectrophotometric assays with commercially available kits (Boehringher Mannheim) in a Cobas-Bio autoanalizer. One unit of LDH activity is the amount of enzyme catalyzing the formation of 1 .mu.mol of NADH per minute at 30.degree. C. The reaction catalyzed by LDH is:
Lactate+NAD.sup.+ =Pyruvate+NADH+H.sup.+
After the incubation with different doses of tungstate, an increase in LDH release was observed at 1 mM dose after 24 hours of incubation.
The mitochondrial function was analyzed in rat hepatocytes, this test is based on the reduction of yellow tetrazolium salts to an insoluble blue compound due to the activity of the mitochondrial enzyme succinate dehydrogenase. The test was performed after 24 hours of incubation with sodium tungstate. The cytotoxic indexes, IC.sub.10 and IC.sub.50, were calculated mathematically form the dose-response curves. These indexes indicate the theoretical concentration of tungstate which induces some toxic effects on the 10 or 50% of the cells, respectively. For rat hepatocytes, four rats were used and the cells were incubated with different doses of sodium tungstate between 0.26-2 mM to calculate the IC values, which were: IC.sub.10 =0.6 mM and IC.sub.50 =1,2 mM.
2
Differential effects of vanadium, tungsten and molybdenum on inhibition of glucose formation in renal tubules and hepatocytes of control and diabetic rabbits: Beneficial action of melatonin and N-acetylcysteine
A. Kiersztan1, K. Winiarska1, J. Drozak1, M. Przedlacka1, M. Wegrzynowicz1, T. Fraczyk1 and J. Bryla1
(1) Department of Metabolic Regulation, Institute of Biochemistry, Warsaw University, Warszawa, Poland
Abstract Effect of vanadyl acetylacetonate (VAc), tungstate and molybdate on gluconeogenesis has been studied in isolated hepatocytes and kidney-cortex tubules. In renal tubules of control and alloxan-diabetic animals, the rank order of the metal-compounds-induced (i) inhibition of glucose formation from alanine + glycerol + octanoate or aspartate + glycerol + octanoate, (ii) decrease in the mitochondrial membrane potential ( m), (iii) increase in the hydroxyl free radicals (HFR) generation and (iv) decline in glucose-6-phosphatase activity was the following: VAc > tungstate > molybdate. Moreover, in contrast to VAc, both tungstate and molybdate at 100 M concentration did not practically decrease glucose production in hepatocytes isolated from diabetic rabbits, and significantly increased the rate of lactate formation in renal tubules. N-acetylcysteine at 2 mM concentration partially attenuated vanadium-induced alterations in glucose formation, m and the cellular glutathione redox state, whereas 0.1 mM melatonin did not abolish vanadium-induced changes in gluconeogenesis despite attenuation of vanadium effects on HFR formation and m decline. However, similarly to control rabbits, following 6 days of intraperitoneal administration of both VAc (1.275 mg V/kg body weight daily) and melatonin (1 mg/kg body weight daily) to alloxan-diabetic animals, vanadium-induced elevated serum creatinine and urea levels were decreased, indicating the beneficial effect of melatonin on diabetes- and vanadium-induced nephrotoxicity in rabbits. As serum glucose levels were also significantly diminished by vanadium + melatonin treatment of diabetic animals, the combination therapy of vanadium compounds and melatonin needs a careful evaluation. (Mol Cell Biochem 261: 9–21, 2004)