Citations

Chronically implantable neurostimulation devices are becoming a clinically viable option for treating patients with neurological disease and psychiatric disorders. Neurostimulation offers the ability to probe and manipulate distributed networks of interacting brain areas in dysfunctional circuits. Here, we use tools from network control theory to examine the dynamic reconfiguration of functionally interacting neuronal ensembles during targeted neurostimulation of cortical and subcortical brain structures. By integrating multimodal intracranial recordings and diffusion-weighted imaging from patients with drug-resistant epilepsy, we test hypothesized structural and functional rules that predict altered patterns of synchronized local field potentials. We demonstrate the ability to predictably reconfigure functional interactions depending on stimulation strength and location. Stimulation of areas with structurally weak connections largely modulates the functional hubness of downstream areas and concurrently propels the brain towards more difficult-to-reach dynamical states. By using focal perturbations to bridge large-scale structure, function, and markers of behavior, our findings suggest that stimulation may be tuned to influence different scales of network interactions driving cognition.

Background: Dihydroergotamine (DHE), a proven migraine treatment, currently has product labeling warning against concomitant use of CYP3A4 inhibitors because of potential drug interactions. However, no reported studies of such interactions with DHE administered by any route are available. Methods: The pharmacokinetics (PK) of MAP0004, an investigative inhaled DHE formulation, were assessed in human subjects with and without CYP3A4 inhibition by ketoconazole to evaluate the potential for drug interaction, elevation of DHE levels, and increased adverse effects. Results: After MAP0004 alone vs. MAP0004 plus ketoconazole, the DHE maximum concentrations (C max ) and area-under-the-curve (AUC 0–48 and AUC 0–∞ ) were not statistically significantly different nor was the C max of the primary metabolite, 8’-OH-DHE. A difference in 8’-OH-DHE AUCs was observed between MAP0004 with and without ketoconazole; however, the concentrations were very low. MAP0004 was well tolerated after both treatments. Conclusions: This study demonstrated that CYP3A4 inhibition had little to no effect on DHE PK after MAP0004 administration, apparently because of its high systemic and low gastrointestinal bioavailability. CYP3A4 inhibition slowed elimination of the metabolite 8’-OH-DHE, but concentrations were too low to be pharmacologically relevant.