Preoperative NLCR measurement corresponds with a glial brain tumor grading.

Hydrogen sulfide (H2S) and inorganic polysulfides are important signaling molecules; however, little is known about their role in the adipose tissue. We examined the effect of H2S and polysulfides on adipose tissue lipolysis. H2S and polysulfide production by mesenteric adipose tissue explants in rats was measured. The effect of Na2S and Na2S4, the H2S and polysulfide donors, respectively, on lipolysis markers, plasma non-esterified fatty acids (NEFA) and glycerol, was examined. Na2S but not Na2S4 increased plasma NEFA and glycerol in a time- and dose-dependent manner. Na2S increased cyclic AMP but not cyclic GMP concentration in the adipose tissue. The effect of Na2S on NEFA and glycerol was abolished by the specific inhibitor of protein kinase A, KT5720. The effect of Na2S on lipolysis was not abolished by propranolol, suggesting no involvement of β-adrenergic receptors. In addition, Na2S had no effect on phosphodiesterase activity in the adipose tissue. Obesity induced by feeding rats a highly palatable diet for 1 month was associated with increased plasma NEFA and glycerol concentrations, as well as greater H2S production in the adipose tissue. In conclusion, H2S stimulates lipolysis and may contribute to the enhanced lipolysis associated with obesity.

Hydrogen sulfide (H2S) and inorganic polysulfides are important signaling molecules; however, little is known about their role in adipose tissue. We examined the effect of H2S and polysulfides on insulin sensitivity of the adipose tissue in rats. Plasma glucose, insulin, non-esterified fatty acids, and glycerol were measured after administration of H2S and the polysulfide donors, Na2S and Na2S4, respectively. In addition, the effect of Na2S and Na2S4 on insulin-induced glucose uptake and inhibition of lipolysis was studied in adipose tissue explants ex vivo. Na2S and Na2S4 administered in vivo at a single dose of 100 μmol/kg had no effect on plasma glucose and insulin concentrations. In addition, Na2S and Na2S4 did not modify the effect of insulin on plasma glucose, fatty acids, and glycerol concentrations. Na2S and Na2S4had no effect on the antilipolytic effect of insulin in adipose tissue explants ex vivo. The effect of insulin on 2-deoxyglucose uptake by adipose tissue was impaired in obese rats which was accompanied by lower insulin-induced tyrosine phosphorylation of IRS-1 and Akt. Na2S4, but not Na2S, improved insulin signaling and increased insulin-stimulated 2-deoxyglucose uptake by adipose tissue of obese rats. The results suggest that polysulfides may normalize insulin sensitivity, at least in the adipose tissue, in obesity/metabolic syndrome.

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