T-1095A and T-1095 are synthetic agents derived from phlorizin, a specific inhibitor of Na+-glucose cotransporters (SGLTs). Unlike phlorizin, T-1095 is absorbed into the circulation via oral administration, is metabolized to the active form, T-1095A, and suppresses the activity of SGLTs in the kidney. Orally administered T-1095 increases urinary glucose excretion in diabetic animals, thereby decreasing blood glucose levels. Indeed, the postprandial hyperglycemia after a meal load was shown to be suppressed by this compound in streptozotocin (STZ)-induced diabetic rats. With long-term T-1095 treatment, both blood glucose and HbA1c levels were reduced in STZ-induced diabetic rats and yellow KK mice. In addition, there was amelioration of abnormal carbohydrate metabolism, i.e., hyperinsulinemia and hypertriglyceridemia, and of the development of microalbuminuria, in yellow KK mice. Thus, T-1095 may be a useful antidiabetic drug, providing a novel therapeutic approach for diabetes.

BackgroundCanagliflozin is a sodium glucose co-transporter (SGLT) 2 inhibitor in clinical development for the treatment of type 2 diabetes mellitus (T2DM).Methods 14C-alpha-methylglucoside uptake in Chinese hamster ovary-K cells expressing human, rat, or mouse SGLT2 or SGLT1; 3H-2-deoxy-d-glucose uptake in L6 myoblasts; and 2-electrode voltage clamp recording of oocytes expressing human SGLT3 were analyzed. Graded glucose infusions were performed to determine rate of urinary glucose excretion (UGE) at different blood glucose (BG) concentrations and the renal threshold for glucose excretion (RTG) in vehicle or canagliflozin-treated Zucker diabetic fatty (ZDF) rats. This study aimed to characterize the pharmacodynamic effects of canagliflozin in vitro and in preclinical models of T2DM and obesity.ResultsTreatment with canagliflozin 1 mg/kg lowered RTG from 415±12 mg/dl to 94±10 mg/dl in ZDF rats while maintaining a threshold relationship between BG and UGE with virtually no UGE observed when BG was below RTG. Canagliflozin dose-dependently decreased BG concentrations in db/db mice treated acutely. In ZDF rats treated for 4 weeks, canagliflozin decreased glycated hemoglobin (HbA1c) and improved measures of insulin secretion. In obese animal models, canagliflozin increased UGE and decreased BG, body weight gain, epididymal fat, liver weight, and the respiratory exchange ratio.ConclusionsCanagliflozin lowered RTG and increased UGE, improved glycemic control and beta-cell function in rodent models of T2DM, and reduced body weight gain in rodent models of obesity.

Recently, human interleukin 18 (hIL-18) cDNA was cloned, and the recombinant protein with a tentatively assigned NH 2 -terminal amino acid sequence was generated. However, natural hIL-18 has not yet been isolated, and its cellular processing is therefore still unclear. To clarify this, we purified natural hIL-18 from the cytosolic extract of monocytic THP.1 cells. Natural hIL-18 exhibited a molecular mass of 18.2 kDa, and the NH 2 -terminal amino acid was Tyr 37 . Biological activities of the purified protein were identical to those of recombinant hIL-18 with respect to the enhancement of natural killer cell cytotoxicity and interferon-␥ production by human peripheral blood mononuclear cells. We also found two precursor hIL-18 (prohIL-18)-processing activities in the cytosol of THP.1 cells. These activities were blocked separately by the caspase inhibitors Ac-YVAD-CHO and Ac-DEVD-CHO. Further analyses of the partially purified enzymes revealed that one is caspase-1, which cleaves prohIL-18 at the Asp 36 -Tyr 37 site to generate the mature hIL-18, and the other is caspase-3, which cleaves both precursor and mature hIL-18 at Asp 71 -Ser 72 and Asp 76 -Asn 77 to generate biologically inactive products. These results suggest that the production and processing of natural hIL-18 are regulated by two processing enzymes, caspase-1 and caspase-3, in THP.1 cells. Interleukin (IL)1 -18 (originally called IGIF, interferon-␥-inducing factor) is a novel cytokine with multiple biological functions. In 1995 we purified murine IL-18 from the liver extracts of mice sensitized with Propionibacterium acnes followed by elicitation with lipopolysaccaride (1). The cDNA of murine IL-18 was cloned from cDNA libraries prepared from the livers of mice with endotoxin shock (2). Using this as a probe, human IL-18 cDNA was also cloned from a human normal liver cDNA library (3). The recombinant human IL-18 with a tentatively assigned NH 2 -terminal amino acid based on its homology with the natural murine IL-18 sequence was expressed in Escherichia coli, and its biological activities were examined (3).IL-18 has an interleukin 1 (IL-1) signature-like sequence (3) as reported and is similar to the IL-1 family and fibroblast growth factor in terms of their trefoil structures (4, 5). Despite their similarities, IL-18 and IL-1␤ exhibit different biological activities (2, 3, 6), transmitted through their specific receptors.2 Genetic information suggested that IL-18 is synthesized as an inactive precursor form (prohIL-18) and that this prohIL-18 has no known signal peptide sequence. Therefore, proteolytic cleavage is required for its maturation like IL-1␤ (2, 3, 7, 8). Gu et al. (7) reported that IL-1␤-converting enzyme (ICE)/ caspase-1 cleaved murine proIL-18 at the authentic processing site, Asp 35 -Asn 36 , to generate biologically active mature murine IL-18. However, natural hIL-18 had not yet been isolated, and its maturation site remained unclear.In this report, we screened for hIL-18 mRNA-expressing cell lines and purified natural hIL-18 from ...

1 The therapeutic e ects of an orally active inhibitor of Na + -glucose cotransporter (SGLT), T-1095 (a derivative of phlorizin; 3-(benzo [b]furan-5-yl)-2',6'-dihydroxy-4'-methylpropiophenone 2'-O-(6-O-methoxycarbonyl-b-D-glycopyranoside)) were examined in C57BL/KsJ-db/db (db/db) mice, a genetic animal model of obese type 2 diabetes. 2 The higher renal SGLT activity in db/db mice than normoglycaemic C57BL/KsJ-db/+m (db/ +m) mice may support the rationale for using an SGLT inhibitor in the treatment regimen for type 2 diabetes. Both T-1095 and its metabolite, T-1095A, which had approximately 10 times more potency, e ectively inhibited renal SGLT activity of these mice in vitro.3 Single oral administration of T-1095 (10, 30, 100 mg kg 71 , p.o.) to db/db mice caused a dosedependent reduction in blood glucose levels and a concomitant increase in glucose excretion into urine. In contrast, T-1095 only slightly a ected blood glucose levels in db/+m mice. 4 Chronic administration of T-1095 (0.1% w w 71 pellet chow, for 12 weeks) decreased blood glucose and haemoglobin A 1C levels, and improved glucose intolerance in db/db mice. The agerelated decrease in plasma insulin levels was markedly inhibited and there was a 2.5 fold increase of insulin content in the pancreas of T-1095-treated db/db mice. Food consumption was not changed, while impaired body weight gain was ameliorated by T-1095 treatment. 5 Both the development of albuminuria and the expansion of glomerular mesangial area in db/db mice were signi®cantly suppressed by chronic T-1095 treatment, indicating the prevention of the progression of diabetic nephropathy. 6 These results demonstrate that the SGLT inhibitor T-1095 is able to improve the metabolic abnormalities and inhibit the development of diabetic complications in db/db mice. Thus, T-1095 can be used for therapy of type 2 diabetic patients.

IntroductionSodium glucose co-transporter 2 (SGLT2) inhibitors exhibit diuretic activity, which is a possible mechanism underlying the cardiovascular benefit of these inhibitors. However, the osmotic diuresis-induced increase in urine volume, and the risk of dehydration have been of concern with SGLT2 inhibitor treatment. This study aimed to investigate the mechanism underlying SGLT2 inhibitor canagliflozin-induced diuresis in Japanese type 2 diabetes mellitus (T2DM) patients.MethodsThirteen T2DM patients received a daily oral dose of 100 mg canagliflozin before breakfast for 6 days. Blood and urine samples were collected at predetermined time points. The primary endpoint was evaluation of correlations between changes from baseline in urine volume and factors that are known to affect urine volume and between actual urine volume and these factors.ResultsCanagliflozin transiently increased urine volume and urinary sodium excretion on Day 1 with a return to baseline levels thereafter. Canagliflozin administration increased urinary glucose excretion, which was sustained during repeated-dose administration. Plasma atrial natriuretic peptide (ANP) and N-terminal pro-b-type natriuretic peptide (NT-proBNP) levels decreased, while plasma renin activity increased. On Day 1 of treatment, changes in sodium and potassium excretion were closely correlated with changes in urine output. A post hoc multiple regression analysis showed changes in sodium excretion and water intake as factors that affected urine volume change at Day 1. Furthermore, relative to that at baseline, canagliflozin decreased blood glucose throughout the day and increased plasma total GLP-1 after breakfast.ConclusionCanagliflozin induced transient sodium excretion and did not induce water intake at Day 1; hence, natriuresis rather than glucose-induced osmotic diuresis may be a major factor involved in the canagliflozin-induced transient increase in urine output. In addition, canagliflozin decreased plasma ANP and NT-proBNP levels and increased plasma renin activity, which may be a compensatory mechanism for sodium retention, leading to subsequent urine output recovery.Clinical trial registrationUMIN000019462.FundingMitsubishi Tanabe Pharma Corporation.Electronic supplementary materialThe online version of this article (doi:10.1007/s12325-016-0457-8) contains supplementary material, which is available to authorized users.