(1S)-1,5-anhydro-1-[5-(4-ethoxybenzyl)-2-methoxy-4-methylphenyl]-1-thio-D-glucitol (TS-071) is a potent, selective sodium-dependent glucose cotransporter 2 (SGLT2) inhibitor for type 2 diabetes treatment

Derivatives of a novel scaffold, C-phenyl 1-thio-D-glucitol, were prepared and evaluated for sodium-dependent glucose cotransporter (SGLT) 2 and SGLT1 inhibition activities. Optimization of substituents on the aromatic rings afforded five compounds with potent and selective SGLT2 inhibition activities. The compounds were evaluated for in vitro human metabolic stability, human serum protein binding (SPB), and Caco-2 permeability. Of them, (1S)-1,5-anhydro-1-[5-(4-ethoxybenzyl)-2-methoxy-4-methylphenyl]-1-thio-D-glucitol (3p) exhibited potent SGLT2 inhibition activity (IC(50) = 2.26 nM), with 1650-fold selectivity over SGLT1. Compound 3p showed good metabolic stability toward cryo-preserved human hepatic clearance, lower SPB, and moderate Caco-2 permeability. Since 3p should have acceptable human pharmacokinetics (PK) properties, it could be a clinical candidate for treating type 2 diabetes. We observed that compound 3p exhibits a blood glucose lowering effect, excellent urinary glucose excretion properties, and promising PK profiles in animals. Phase II clinical trials of 3p (TS-071) are currently ongoing.

Deuterium-resistant algal cell line for D labeling of heterotrophs expresses enhanced level of Hsp60 in D2O medium

Fully deuterated components from autotrophic cell lysate are useful materials for labeling of heterotrophs with deuterium. To facilitate the faster production of deuterated algal lysate, we selected a mutant Chlorella strain that grows faster in heavy water than the wild type. The mutant DR-17 was found to have a higher level of Hsp60 and an elevated level of protein synthesis. We previously isolated a deuterium-resistant yeast cell line that was also found to express elevated level of Hsp70 (K. Unno, T. Kishido, M. Morioka, S. Okada, and N. Oku, Biol. Pharm. Bull. 26:799-802, 2003). This suggests that the overexpression of heat shock proteins is required to compensate for the deuterium isotope effect.

Prediction of differences in in vivo oral clearance of N,N-dipropyl-2-[4-methoxy-3-(2-phenylethoxy)phenyl] ethylamine monohydrochloride (NE-100) between extensive and poor metabolizers from in vitro metabolic data in human liver microsomes lacking CYP2D6 activity and recombinant CYPs

1. It has previously been reported that N,N-dipropyl-2-[4-methoxy-3-(2-phenylethoxy)phenyl]-ethylamine monohydrochloride (NE-100) was predominantly metabolized by cytochrome P450 (CYP) 2D6 in human liver microsomes (HLM). In the present study, the contribution of CYP forms involved in the formation of the major metabolites of NE-100 in human liver lacking CYP2D6 activity (PM-HLM) has been predicted by use of in vitro kinetic data on recombinant CYPs microsomes (rCYPs). 2. In PM-HLM, NE-100 is predicted to be metabolized to N-despropyl-NE-100 (NE-098), p-hydroxy-NE-100 (NE-152) and m-hydroxyl-NE-100 (NE-163), but not to O-demethy-NE-100 (NE-125), which is a major metabolite in pooled human liver microsomes (EM-HLM). The relative activity factor approach assumed that NE-098 formation is predominantly catalysed by CYP3A4 and CYP2C9 and the NE-152+163mix (a mixture of two hydroxylated metabolites, NE-152 and NE-163) formation is only catalysed by CYP3A4. 3. The predicted contribution rates of CYP3A4 and CYP2C9 for NE-098 formation were 58.1 and 34.6%, respectively, in PM-HLM. These predicted results were strongly supported by kinetic and inhibition studies using PM-HLM. The intrinsic clearance of NE-100 predicted from rCYPs (the predicted CLint-HLM-total) corresponded to those observed from EM- and PM-HLM (the observed CLint-HLM). 4. The in vivo oral clearance (CLoral) of NE-100 in extensive metabolizers and poor metabolizers of CYP2D6 was predicted to be 50times higher in extensive metabolizers than poor metabolizers using in vitro-in vivo scaling method based on the dispersion model. These data suggest that polymorphism of CYP2D6 might greatly affect NE-100 metabolism in vivo.

Metabolism of N,N-Dipropyl-2-[4-Methoxy-3-(2-Phenyl-Ethoxy)-Phenyl]-Ethyl-Amine-Monohydrochloride (NE-100), A Novel Sigma Ligand: Contribution of Cytochrome P450 Forms Involved in the Formation of Individual Metabolites in Human Liver and Small Intestine

In the present study, human cytochrome P450 (CYP) forms involved in producing the primary metabolites of NE-100 were identified. Major metabolites of NE-100 in human liver microsomes (HLM) were N-depropylation of NE-100 (NE-098), p-hydroxylation of phenyl group of NE-100 (NE-152), m-hydroxylation of phenyl group of NE-100 (NE-163) and O-demethylation of NE-100 (NE-125). Judging from the correlation and inhibition studies, NE-125 and NE-152+163mix formations were predominantly mediated by CYP2D6 and NE-098 formation was mediated by multiple CYP forms at a low NE-100 concentration (0.1 microM) in the HLM. According to relative activity factor (RAF) approaches, all these reactions were predominantly catalyzed by CYP2D6 at a substrate concentration assuming a plasma level of NE-100 (K(m)>>S) in case of the human liver. Depending on the increase in NE-100 concentrations, the rate of contribution for NE-098 and NE-152+163mix formations increased in CYP3A4, although the predominant contribution of CYP2D6 for NE-125 formation did not change. In human intestinal microsomes (HIM), NE-100 was mainly metabolized to NE-098 and NE-152+163mix by CYP3A4. The intrinsic clearance for their formations in HIM was 3.2 and 14.9 times less than those in HLM, respectively, and no formation of NE-125 was observed in HIM. These results strongly suggest that CYP2D6 is the predominant form for NE-100 metabolism in the human liver in in vivo conditions (K(m)>>S) and the liver plays a more important role than does the small intestine in the first pass metabolism.

Differences in cytochrome P450 forms involved in the metabolism of N,N-dipropyl-2-[4-methoxy-3-(2-phenylethoxy)phenyl]ethylamine monohydrochloride (NE-100), a novel sigma ligand, in human liver and intestine

N,N-Dipropyl-2-[4-methoxy-3-(2-phenylethoxy)phenyl]ethylamine monohydrochloride (NE-100) has been developed to treat subjects with schizophrenia. This drug is mainly excreted in the form of oxidative metabolites. In the present study, identification of p450 forms involved in the metabolism was carried out using human livers and intestinal microsomes (HLM and HIM). Eadie-Hofstee plots for NE-100 disappearance in HLM were biphasic, thus indicating the involvement of at least two p450 forms. The metabolism of NE-100 was mediated with recombinant CYP1A1, CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A4. A significant correlation was observed between activities of NE-100 metabolism and dextromethorphan O-demethylation (a specific activity for CYP2D6) or testosterone 6beta-hydroxylation (a specific activity for CYP3A4) in HLM. The activity of NE-100 metabolism was inhibited by approximately 80% by an anti-CYP2D6 antibody and only by quinidine among the p450-selective inhibitors at a low substrate concentration (0.1 microM). In contrast, with a high substrate concentration (10 microM), the activity was inhibited by an anti-CYP3A4 antibody and by ketoconazole. On the other hand, in HIM, the Eadie-Hofstee plots for NE-100 disappearance were monophasic, and the metabolism was strongly inhibited by an anti-CYP3A4 antibody and by ketoconazole but not by other inhibitors used. These results strongly suggest that NE-100 has different profiles regarding metabolism between liver and intestine. During absorption, NE-100 is mainly metabolized by CYP3A4 in the intestine and thereafter by CYP2D6 in the liver in the presence of therapeutic doses.