Nasal Glucagon Is Easier to Use and More Preferred and Needs Less Effort to Administer Than Injectable Glucagon: User Perceptions of Glucagon Administration During Severe Hypoglycemia Simulation.

OBJECTIVE: To evaluate ease of use, user preference, and effort required to use nasal glucagon (NG) versus injectable glucagon needing reconstitution (IG) in simulations of severe hypoglycemia (SH)-a challenge for caregivers of a person with diabetes (PWD) in real-life. METHODS: In this randomized, crossover study, high-fidelity manikins placed in mock representative high-stress environments were used to simulate an SH rescue. Thirty-two trained (by PWDs) and 33 untrained participants attempted NG and IG administrations and then completed questionnaires regarding ease of use, preference, and workload for each device. RESULTS: More trained users agreed that NG was easy to use (87.1% vs 54.8%) and prepare (80.6% vs 51.6%) and had confidence to use NG correctly (93.5% vs 54.8%) than those who agreed the same for IG (P < .05). Untrained users reported similar differences, favoring NG in all parameters. In direct device comparison across all simulations, 80.6% of trained users and 93.5% of untrained users preferred NG over IG-a preference largely sustained regardless of the success or failure of administration. Among PWDs, 90.3% considered NG device as safer than IG during an SH event. In the assessment of workload required to administer glucagon, the weighted mean National Aeronautics and Space Administration Task Load Index scores were 37.8 for NG and 48.4 for IG (P = .0020). CONCLUSION: Participants in this study considered NG easier, more preferred, required less effort for administration, and more intuitive to use than reconstitutable IG, irrespective of whether there was prior training. NG improves the potential for successful administration of glucagon, better preparedness, and increased adoption of glucagon for SH rescue.

ZFAND1 Recruits p97 and the 26S Proteasome to Promote the Clearance of Arsenite-Induced Stress Granules.

Stress granules (SGs) are cytoplasmic assemblies of mRNPs stalled in translation initiation. They are induced by various stress conditions, including exposure to the environmental toxin and carcinogen arsenic. While perturbed SG turnover is linked to the pathogenesis of neurodegenerative diseases, the molecular mechanisms underlying SG formation and turnover are still poorly understood. Here, we show that ZFAND1 is an evolutionarily conserved regulator of SG clearance. ZFAND1 interacts with two key factors of protein degradation, the 26S proteasome and the ubiquitin-selective segregase p97, and recruits them to arsenite-induced SGs. In the absence of ZFAND1, SGs lack the 26S proteasome and p97, accumulate defective ribosomal products, and persist after arsenite removal, indicating their transformation into aberrant, disease-linked SGs. Accordingly, ZFAND1 depletion is epistatic to the expression of pathogenic mutant p97 with respect to SG clearance, suggesting that ZFAND1 function is relevant to the multisystem degenerative disorder IBMPFD/ALS.

Roles of Hsp104 and trehalose in solubilisation of mutant huntingtin in heat shocked Saccharomyces cerevisiae cells.

Inhibition of huntingtin aggregation, either in the nucleus and/or in the cytosol, has been identified as a major strategy to ameliorate the symptoms of Huntington's disease. Chaperones and other protein stabilisers would thus be key players in ensuring the correct folding of the amyloidogenic protein and its expression in the soluble form. By transient activation of the global heat stress response in Saccharomyces cerevisiaeBY4742, we show that heterologous expression of mutant huntingtin (103Q-htt) could be modulated so that the protein was partitioned off in the soluble fraction of the cytosol. This led to lower levels of reactive oxygen species and improved cell viability. Previous reports had speculated on the relationship between trehalose and the heat shock response in ensuring enhanced cell survival but no direct evidence of such an interaction was available. Using mutants of an isogenic strain which do not express the major trehalose synthetic or metabolising enzymes or the chaperone, heat shock protein 104 (Hsp104), we were able to identify the functions of Hsp104 and the osmoprotectant trehalose in solubilising mutant huntingtin. We propose that the beneficial effect of the protein refolding machinery in solubilising the aggregation-prone protein is exerted by maintaining a tight balance between the trehalose synthetic enzyme, trehalose-6-phosphate synthase 1 and Hsp104. This ensures that the level of the osmoprotectant, trehalose, does not exceed the limit beyond which it is reported to inhibit protein refolding.