Taurine supplementation enhances nutrient-induced insulin secretion in pancreatic mice islets
ABSTRACT Taurine (TAU), a naturally occurring sulfur-containing amino acid, is found at high concentrations in plasma and mammalian tissues and regulates osmolarity, ion channel activity, and glucose homeostasis. Several reports have shown that physiological plasma TAU levels seem to be important for adequate beta (beta)-cell function and insulin action, since low concentrations of TAU in the plasma have been reported in the pre-diabetic and diabetic states.
Glucose tolerance and insulin sensitivity were investigated in mice supplemented with 2% (w/v) TAU in their drinking water for 30 days, as well as the insulin secretion from isolated islets stimulated by glucose or L-leucine.
TAU-supplemented mice demonstrated improved glucose tolerance and higher insulin sensitivity, compared to controls (CTL). In addition, their islets secreted more insulin in response to high concentrations of glucose and L-leucine. L-[U-(14)C]leucine oxidation was higher in TAU than in CTL islets, whereas D-[U-(14)C]glucose oxidation, ATP levels, glucose transporter (GLUT) 2 and glucokinase (GCK) protein expressions were similar in both types of islets. The L-type beta(2) subunit voltage-sensitive Ca(2+) channel protein, as well as (45)Ca uptake, were significantly higher in TAU-supplemented than CTL islets. In addition, islets from TAU-supplemented mice secreted more glucagon than CTL islets at low glucose.
TAU supplementation improves glucose tolerance and insulin sensitivity in mice, as well as insulin secretion from isolated islets. The latter effect seems to be, at least in part, dependent on a better Ca(2+) handling by the islets.
- SourceAvailable from: Letícia M Ignacio-Souza[Show abstract] [Hide abstract]
ABSTRACT: Taurine is known to modulate a number of metabolic parameters such as insulin secretion and action and blood cholesterol levels. Recent data have suggested that taurine can also reduce body adiposity in C. elegans and in rodents. Since body adiposity is mostly regulated by insulin-responsive hypothalamic neurons involved in the control of feeding and thermogenesis, we hypothesized that some of the activity of taurine in the control of body fat would be exerted through a direct action in the hypothalamus. Here, we show that the intracerebroventricular injection of an acute dose of taurine reduces food intake and locomotor activity, and activates signal transduction through the Akt/FOXO1, JAK2/STAT3 and mTOR/AMPK/ACC signaling pathways. These effects are accompanied by the modulation of expression of NPY. In addition, taurine can enhance the anorexigenic action of insulin. Thus, the aminoacid, taurine, exerts a potent anorexigenic action in the hypothalamus and enhances the effect of insulin on the control of food intake.Amino Acids 08/2011; 42(6):2403-10. DOI:10.1007/s00726-011-1045-5 · 3.65 Impact Factor
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ABSTRACT: Taurine has probed to be involved in a wide range of biological processes and to provide several different important health benefits. Its effects have been revealed to be exerted mainly through its antioxidant and anti-inflammatory effects, among other mechanisms. The present review is aimed to provide a solid body of evidence regarding the beneficial effects of taurine in the context of diabetes and its complications, with an special focus on the cardiovascular health impairments so frequently associated to this disease, so that data from this updated systematic review of the literature, may constitute a base to back up future clinical and epidemiological studies, on the possibilities of taurine supplementation as a useful tool for both prevention and treatment of diabetes complications. We consider results from the different experimental, in vitro studies as well as some clinical ones reviewed, to provide sufficient evidence as to constitute a solid base to back up future clinical and epidemiological studies on the usefulness of taurine supplementation both in the prevention and treatment of diabetes and its complications.Nutricion hospitalaria: organo oficial de la Sociedad Espanola de Nutricion Parenteral y Enteral 25(6):910-9. · 1.25 Impact Factor
Conference Paper: Specific charge measurements in electrostatic air sprays[Show abstract] [Hide abstract]
ABSTRACT: An experimental study of the effects of nozzle parameters and fluid properties on specific charge and ratio of ion to drop current for electrostatic air sprays is reported. The specific gun used and the parameter ranges investigated are characteristic of many industrial painting processes. A simple collector system that discriminates between drop and ion currents was used to measure ensemble-averaged specific charge for the drops and the ratio of ion to drop current. The data exhibit a coupled dependence on applied potential, liquid flow rate, atomizing air flow rate, and fluid properties. The trends are consistent with contact charging of the liquid and ion generation during breakup of the bulk liquid into drops. Specific charges range from 0 to 9 μC/g and the ratios of ion to drop currents range from 0 to 6. Analysis of the current ratios indicates that under many conditions the ion charge density near the substrate is small in comparison to the drop charge density. Consequently, the ion charge density may be neglected and only the drop charge density must be considered in simulating the electrostatic fieldsIndustry Applications Society Annual Meeting, 1993., Conference Record of the 1993 IEEE; 11/1993