Long-acting glucagon-like peptide-1 (GLP-1) analogues marketed for type 2 diabetes (T2D) treatment have been showing positive and protective effects in several different tissues, including pancreas, heart or even brain. This gut secreted hormone plays a potent insulinotropic activity and an important role in maintaining glucose homeostasis. Furthermore, growing evidences suggest the occurrence of several commonalities between T2D and neurodegenerative diseases, insulin resistance being pointed as a main cause for cognitive decline and increased risk to develop dementia. In this regard, it has also been suggested that stimulation of brain insulin signaling may have a protective role against cognitive deficits. As GLP-1 receptors (GLP-1R) are expressed throughout the central nervous system and GLP-1 may cross the blood-brain-barrier, an emerging hypothesis suggests that they may be promising therapeutic targets against brain dysfunctional insulin signaling-related pathologies. Importantly, GLP-1 actions depend not only on the direct effect mediated by its receptor activation, but also on the gut-brain axis involving an exchange of signals between both tissues via the vagal nerve, thereby regulating numerous physiological functions (e.g., energy homeostasis, glucose-dependent insulin secretion, as well as appetite and weight control). Amongst the incretin/GLP-1 mimetics class of anti-T2D drugs with an increasingly described neuroprotective potential, the already marketed liraglutide emerged as a GLP-1R agonist highly resistant to dipeptidyl peptidase-4 degradation (thereby having an increased half-life) and whose systemic GLP-1R activity is comparable to that of native GLP-1. Importantly, several preclinical studies showed anti-apoptotic, anti-inflammatory, anti-oxidant and neuroprotective effects of liraglutide against T2D, stroke and Alzheimer disease (AD), whereas several clinical trials, demonstrated some surprising benefits of liraglutide on weight loss, microglia inhibition, behavior and cognition, and in AD biomarkers. Herein, we discuss the GLP-1 action through the gut-brain axis, the hormone's regulation of some autonomic functions and liraglutide's neuroprotective potential.

The presence of age-related comorbidities prone elderly patients to the phenomenon of polypharmacy and consequently to a higher risk of nonadherence. Thus, this paper aims to characterize the medication consumption profile and explore the relationship of beliefs and daily medication management on medication adherence by home-dwelling polymedicated elderly people. A questionnaire on adherence, managing, and beliefs of medicines was applied to polymedicated patients with ≥65 years old, in primary care centers of the central region of Portugal. Of the 1089 participants, 47.7% were considered nonadherent. Forgetfulness (38.8%), difficulties in managing medication (14.3%), concerns with side effects (10.7%), and the price of medication (9.2%) were pointed as relevant medication nonadherence-related factors. It was observed that patients who had difficulties managing medicines, common forgetfulness, concerns with side effects, doubting the need for the medication, considered prices expensive, and had a lack of trust for some medicines had a higher risk of being nonadherent. This study provides relevant information concerning the daily routine and management of medicines that can be useful to the development of educational strategies to promote health literacy and improve medication adherence in polymedicated home-dwelling elderly.