A randomized, placebo-controlled study to evaluate the efficacy and safety of adding omarigliptin to insulin therapy in Japanese patients with type 2 diabetes and inadequate glycaemic control.

Aim: To evaluate the efficacy and safety of adding the once-weekly oral dipeptidyl peptidase-4 inhibitor omarigliptin to treatment of Japanese patients with type 2 diabetes and inadequate glycaemic control on insulin monotherapy.

Materials And Methods: In a 52-week clinical trial, Japanese patients on insulin monotherapy were randomized to once-weekly omarigliptin 25 mg (N = 123) or placebo (N = 61) for a 16-week, double-blind, placebo-controlled period. After Week 16, patients continued or switched to omarigliptin for a 36-week open-label period.

Electrochemical sensing system employing fructosamine 6-kinase enables glycated albumin measurement requiring no proteolytic digestion.

Currently available enzymatic methods for the measurement of glycated proteins utilize fructosyl amino acid/peptide oxidases (FAOXs/FPOXs) as sensing elements. FAOXs/FPOXs oxidize glycated amino acids or glycated dipeptides but they are not able to accept longer glycated peptides or intact glycated proteins as substrates. Therefore, pretreatment via proteolytic digestion is unavoidable with the current enzymatic methods, and there remains a need for simpler measurement methods for glycated proteins.

Advancing the development of glycated protein biosensing technology: next-generation sensing molecules.

Research advances in biochemical molecules have led to the development of convenient and reproducible biosensing molecules for glycated proteins, such as those based on the enzymes fructosyl amino acid oxidase (FAOX) or fructosyl peptide oxidase (FPOX). Recently, more attractive biosensing molecules with potential applications in next-generation biosensing of glycated proteins have been aggressively reported. We review 2 such molecules, fructosamine 6-kinase (FN6K) and fructosyl amino acid-binding protein, as well as their recent applications in the development of glycated protein biosensing systems.

Cloning and characterization of fructosamine-6-kinase from Arthrobacter aurescens.

Fructosamine-6-kinases (FN6Ks) that catalyze phosphorylation of glycated amino acids, i.e., fructosyl amino acids (FAs), have been shown as a potential recognition element for glycated protein detection.

Substrate specificity engineering of Escherichia coli derived fructosamine 6-kinase.

A three-dimensional structural model of Escherichia coli fructosamine 6-kinase (FN6K), an enzyme that phosphorylates fructosamines at C6 and catalyzes the production of the fructosamine 6-phosphate stable intermediate, was generated using the crystal structure of 2-keto-3-deoxygluconate kinase isolated from Thermus thermophilus as template. The putative active site region was then investigated by site-directed mutagenesis to reveal several amino acid residues that likely play important roles in the enzyme reaction. Met220 was identified as a residue that plays a role in substrate recognition when compared to Bacillus subtilis derived FN6K, which shows different substrate specificity from the E.