Pharmacokinetic and pharmacodynamic profile of the sodium-glucose co-transporter-2 inhibitor empagliflozin in young people with Type 2 diabetes: a randomized trial.

AIMS: To assess the pharmacokinetic and pharmacodynamic profile of a single dose of empagliflozin in young people with Type 2 diabetes to identify the appropriate doses for further paediatric development. METHODS: We conducted a single-dose, open-label, randomized, parallel-group study with empagliflozin 5 mg, 10 mg and 25 mg in young people with Type 2 diabetes aged 10-17 years. RESULTS: Of 39 participants screened, 27 were randomized and completed the study; their mean (± sd) age was 14.1±2.0 years and body weight was 96.7±23.5 kg. Compared with similar studies in adults with Type 2 diabetes, the maximum observed plasma concentrations were slightly lower with the 10-mg and 25-mg doses, and the area under the plasma concentration-time curve was slightly lower with the 10-mg but slightly higher with the 25-mg dose. The adjusted mean increases in urinary glucose excretion were 53 g/24 h (95% CI 32,74), 73 g/24 h (95% CI 52,94) and 87 g/24 h (95% CI 68,107), and the adjusted mean decreases in fasting plasma glucose were 0.9 mmol/l (95% CI -1.6,-0.1), 0.9 mmol/l (95% CI -1.7,-0.2) and 1.1 mmol/l (95% CI -1.8,-0.5) for the 5- 10- and 25-mg doses, respectively. There were no serious adverse events and one investigator-reported drug-related event (dehydration). CONCLUSIONS: After a single oral dose of empagliflozin, adults and young people with Type 2 diabetes had similar exposure-response relationships after adjusting for significant covariates. These data support testing 10-mg and/or 25-mg doses of empagliflozin in an upcoming paediatric phase III Type 2 diabetes trial. (ClinicalTrials.gov registration no.: NCT02121483).

The use of substrate materials and topography to modify growth patterns and rates of differentiation of muscle cells.

Cells are cultured on platforms made of a variety of materials with selected topographies during studies of cell response and behavior. Understanding the effects of substrates is essential for such applications as developing effective interfaces between body cells and implanted materials and devices. In this study, the effects of substrate surface properties on cell differentiation and alignment on C2C12 myoblasts cultured on conventional or fabricated polymeric cell culture substrates were investigated. Comparisons were made between cells cultured on tissue culture grade polystyrene (TCPS), glass, Permanox, and cured polydimethylsiloxane (PDMS) substrates. Fluorescent immunohistochemistry of cell markers was used to analyse the extent of differentiation. Alignment and guidance of cell growth and spread were studied using patterned platforms. Gratings were made on polystyrene (PS) and PDMS and differentiation was facilitated after 5 days by media exchange. Differences in cell morphology were observed between cells cultured on TCPS and PDMS substrates. Fully differentiated myotubes were observed in highest numbers on TCPS substrates and were non-detectable on PDMS substrates in the time frame of 144 h. Muscle cell alignment and their differentiation followed along the grating patterns on PS and elongated along the pattern length. On the other hand, on PDMS cells formed sheets of tissue and peeled from the substrate. We have revealed the potential for the combinations of surface materials and topography on cell behavior to induce accelerated differentiation and coordinated alignment. The results demonstrate that culture environment can be designed or engineered to modify or regulate muscle cell functions. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1638-1645, 2016.

Positive and negative bioimprinted polymeric substrates: new platforms for cell culture.

Bioimprinting, which involves capturing cell morphological details into a polymer matrix, provides a new class of patterned surfaces which opens an opportunity to investigate how cells respond to their own signatures and may introduce possibilities for regulating their behaviour. In this study, phenotypic details of human nasal chondrocytes (HNCs) were replicated in soft polydimethylsiloxane (PDMS) mould resulting in inverse replicas of cells, which have been termed here as 'negative bioimprint'. For the first time, the information from this negative bioimprint was then transferred into another PDMS layer resulting in surfaces which resemble cell morphology and were called 'positive bioimprints'. Soft lithography was used to transfer these details from PDMS into different polymers like polystyrene, tissue culture polystyrene and clinically used block co-polymer poly (ethylene glycol) terephthalate-poly (butylene terephthalate) (PEGT-PBT). Results obtained from surface characterization confirmed that fine details of cells were successfully replicated from cells to different polymer matrices without any significant loss of information during the different steps of pattern transfer. HNCs seeded on different polymer surfaces with positive and negative bioimprints exhibited distinct behaviour. Cells cultured on positive bioimprints were more spread out and displayed high levels of proliferation compared to those on negative bioimprints, where cells were more compact with lower proliferation.

Versatile multi-functionalization of protein nanofibrils for biosensor applications.

Protein nanofibrils offer advantages over other nanostructures due to the ease in their self-assembly and the versatility of surface chemistry available. Yet, an efficient and general methodology for their post-assembly functionalization remains a significant challenge. We introduce a generic approach, based on biotinylation and thiolation, for the multi-functionalization of protein nanofibrils self-assembled from whey proteins. Biochemical characterization shows the effects of the functionalization onto the nanofibrils' surface, giving insights into the changes in surface chemistry of the nanostructures. We show how these methods can be used to decorate whey protein nanofibrils with several components such as fluorescent quantum dots, enzymes, and metal nanoparticles. A multi-functionalization approach is used, as a proof of principle, for the development of a glucose biosensor platform, where the protein nanofibrils act as nanoscaffolds for glucose oxidase. Biotinylation is used for enzyme attachment and thiolation for nanoscaffold anchoring onto a gold electrode surface. Characterization via cyclic voltammetry shows an increase in glucose-oxidase mediated current response due to thiol-metal interactions with the gold electrode. The presented approach for protein nanofibril multi-functionalization is novel and has the potential of being applied to other protein nanostructures with similar surface chemistry.