First-in-human study of a pharmacological duodenal exclusion therapy shows reduced postprandial glucose and insulin and increased bile acid and gut hormone concentrations.

AIMS: To address the need for noninvasive alternatives to metabolic surgery or duodenal exclusion devices for the management of type 2 diabetes (T2D) and obesity by developing an orally administered therapeutic polymer, GLY-200, designed to bind to and enhance the barrier function of mucus in the gastrointestinal tract to establish duodenal exclusion noninvasively. MATERIALS AND METHODS: A Phase 1, randomized, double-blind, placebo-controlled, single- (SAD) and multiple-ascending-dose (MAD) healthy volunteer study was conducted. In the SAD arm, four cohorts received a single dose of 0.5 g up to 6.0 g GLY-200 or placebo, while in the MAD arm, four cohorts received 5 days of twice-daily or three-times-daily dosing (total daily dose 2.0 g up to 6.0 g GLY-200 or placebo). Assessments included safety and tolerability (primary) and exploratory pharmacodynamics, including serum glucose, insulin, bile acids and gut hormones. RESULTS: No safety signals were observed; tolerability signals were limited to mild to moderate dose-dependent gastrointestinal events. In the MAD arm (Day 5), reductions in glucose and insulin and increases in bile acids, glucagon-like peptide-1, peptide YY and glicentin, were observed following a nonstandardized meal in subjects receiving twice-daily dosing of 2.0 g GLY-200 (N = 9) versus those receiving placebo (N = 8). CONCLUSIONS: GLY-200 is safe and generally well tolerated at doses of ≤2.0 g twice daily. Pharmacodynamic results mimic the biomarker signature observed after Roux-en-Y gastric bypass and duodenal exclusion devices, indicating a pharmacological effect in the proximal small intestine. This study represents the first clinical demonstration that duodenal exclusion can be achieved with an oral drug and supports further development of GLY-200 for the treatment of obesity and/or T2D.

Sustained deep-tissue voltage recording using a fast indicator evolved for two-photon microscopy.

Genetically encoded voltage indicators are emerging tools for monitoring voltage dynamics with cell-type specificity. However, current indicators enable a narrow range of applications due to poor performance under two-photon microscopy, a method of choice for deep-tissue recording. To improve indicators, we developed a multiparameter high-throughput platform to optimize voltage indicators for two-photon microscopy. Using this system, we identified JEDI-2P, an indicator that is faster, brighter, and more sensitive and photostable than its predecessors. We demonstrate that JEDI-2P can report light-evoked responses in axonal termini of Drosophila interneurons and the dendrites and somata of amacrine cells of isolated mouse retina. JEDI-2P can also optically record the voltage dynamics of individual cortical neurons in awake behaving mice for more than 30 min using both resonant-scanning and ULoVE random-access microscopy. Finally, ULoVE recording of JEDI-2P can robustly detect spikes at depths exceeding 400 µm and report voltage correlations in pairs of neurons.

Nanofiber-hydrogel composite-mediated angiogenesis for soft tissue reconstruction.

Soft tissue losses from tumor removal, trauma, aging, and congenital malformation affect millions of people each year. Existing options for soft tissue restoration have several drawbacks: Surgical options such as the use of autologous tissue flaps lead to donor site defects, prosthetic implants are prone to foreign body response leading to fibrosis, and fat grafting and dermal fillers are limited to small-volume defects and only provide transient volume restoration. In addition, large-volume fat grafting and other tissue-engineering attempts are hampered by poor vascular ingrowth. Currently, there are no off-the-shelf materials that can fill the volume lost in soft tissue defects while promoting early angiogenesis. Here, we report a nanofiber-hydrogel composite that addresses these issues. By incorporating interfacial bonding between electrospun poly(ε-caprolactone) fibers and a hyaluronic acid hydrogel network, we generated a composite that mimics the microarchitecture and mechanical properties of soft tissue extracellular matrix. Upon subcutaneous injection in a rat model, this composite permitted infiltration of host macrophages and conditioned them into the pro-regenerative phenotype. By secreting pro-angiogenic cytokines and growth factors, these polarized macrophages enabled gradual remodeling and replacement of the composite with vascularized soft tissue. Such host cell infiltration and angiogenesis were also observed in a rabbit model for repairing a soft tissue defect filled with the composite. This injectable nanofiber-hydrogel composite augments native tissue regenerative responses, thus enabling durable soft tissue restoration outcomes.

Generation of Homogenous Three-Dimensional Pancreatic Cancer Cell Spheroids Using an Improved Hanging Drop Technique.

In vitro characterization of tumor cell biology or of potential anticancer drugs is usually performed using tumor cell lines cultured as a monolayer. However, it has been previously shown that three-dimensional (3D) organization of the tumor cells is important to provide insights on tumor biology and transport of therapeutics. Several methods to create 3D tumors in vitro have been proposed, with hanging drop technique being the most simple and, thus, most frequently used. However, in many cell lines this method has failed to form the desired 3D tumor structures. The aim of this study was to design and test an easy-to-use and highly reproducible modification of the hanging drop method for tumor sphere formation by adding methylcellulose polymer. Most pancreatic cancer cells do not form cohesive and manageable spheres when the original hanging drop method is used, thus we investigated these cell lines for our modified hanging drop method. The spheroids produced by this improved technique were analyzed by histology, light microscopy, immunohistochemistry, and scanning electron microscopy. Results show that using the proposed simple method; we were able to produce uniform spheroids for all five of the tested human pancreatic cancer cell lines; Panc-1, BxPC-3, Capan-1, MiaPaCa-2, and AsPC-1. We believe that this method can be used as a reliable and reproducible technique to make 3D cancer spheroids for use in tumor biology research and evaluation of therapeutic responses, and for the development of bio-artificial tissues.

Radiofrequency treatment alters cancer cell phenotype.

The importance of evaluating physical cues in cancer research is gradually being realized. Assessment of cancer cell physical appearance, or phenotype, may provide information on changes in cellular behavior, including migratory or communicative changes. These characteristics are intrinsically different between malignant and non-malignant cells and change in response to therapy or in the progression of the disease. Here, we report that pancreatic cancer cell phenotype was altered in response to a physical method for cancer therapy, a non-invasive radiofrequency (RF) treatment, which is currently being developed for human trials. We provide a battery of tests to explore these phenotype characteristics. Our data show that cell topography, morphology, motility, adhesion and division change as a result of the treatment. These may have consequences for tissue architecture, for diffusion of anti-cancer therapeutics and cancer cell susceptibility within the tumor. Clear phenotypical differences were observed between cancerous and normal cells in both their untreated states and in their response to RF therapy. We also report, for the first time, a transfer of microsized particles through tunneling nanotubes, which were produced by cancer cells in response to RF therapy. Additionally, we provide evidence that various sub-populations of cancer cells heterogeneously respond to RF treatment.