Research indicates that by 2050, more than 150 million people will be living with Alzheimer's disease (AD), a condition associated with neurodegeneration due to the accumulation of amyloid-beta and tau proteins. In addition to genetic background, endocrine disruption, and cellular senescence, management of the gut microbiota has emerged as a key element in the diagnosis, progression, and treatment of AD, as certain bacterial metabolites can travel through the bloodstream and cross the blood-brain barrier. This mini-review explores the relationship between tau protein accumulation and gut dysbiosis in Drosophila melanogaster. This model facilitates the investigation of how gut-derived metabolites contribute to neurocognitive impairment and dementia. Understanding the role of direct and indirect bacterial by-products, such as lactate and acetate, in glial cell activation and tau protein dynamics may provide insights into the mechanisms of AD progression and contribute to more effective treatments. Here we discuss how the simplicity and extensive genetic tools of Drosophila make it a valuable model for studying these interactions and testing potential therapeutics, including probiotics. Integrating Drosophila studies with other established models may reveal conserved pathways and accelerate the translation of findings into clinical applications.

Older adults are particularly vulnerable to extreme heat, but evidence of the role of social factors in regional heat vulnerability remains limited. To assess the impacts of heat waves on cardiorespiratory hospitalizations and mortality, we developed a Climate Vulnerability Index by the Regional Health Department (RHD), including adults aged ≥ 60 years across 17 RHDs in São Paulo State, Brazil. Health data were obtained from national information systems, and heat wave exposure was derived from ERA5 reanalysis data, defined as periods of at least three consecutive days with daily mean temperature exceeding the seasonal climatological mean by ≥3 °C, for 2010–2019 and 2023–2024, excluding 2020–2022. Associations between heat waves and health outcomes were estimated using distributed lag non-linear models with lags of 0–15 days. Cumulative relative risks, along with sociodemographic, sanitation, and health system indicators, were integrated to construct the Index based on IPCC sensitivity and adaptive capacity domains. Heat waves were associated with increased risks of cardiorespiratory hospitalizations and mortality across all RHDs, with stronger effects observed for mortality and inland regions. Higher vulnerability was concentrated in RHDs characterized by larger older adult populations, greater heat-related risks, and weaker health system and sanitation indicators, whereas more developed regions showed lower vulnerability. Overall, the Index provides a practical tool to support territorial prioritization and targeted heat–health adaptation strategies in ageing populations.

Older adults are particularly vulnerable to extreme heat, but evidence of the role of social factors in regional heat vulnerability remains limited. To assess the impacts of heat waves on cardiorespiratory hospitalizations and mortality, we developed a Climate Vulnerability Index by Regional Health Department (RHD), including adults aged ≥60 years across 17 RHDs in São Paulo State, Brazil. Health data were obtained from national information systems, and heat wave exposure was derived from ERA5 reanalysis data for 2010–2019 and 2023–2024, excluding 2020–2022. Associations between heat waves and health outcomes were estimated using distributed lag non-linear models with lags of 0–15 days. Cumulative relative risks, along with sociodemographic, sanitation, and health system indicators, were integrated to construct the Index based on IPCC sensitivity and adaptive capacity domains. Heat waves were associated with increased risks of cardiorespiratory hospitalizations and mortality across all RHDs, with stronger effects observed for mortality and inland regions. Higher vulnerability was concentrated in RHDs characterized by larger older adult populations, greater heat-related risks, and weaker health system and sanitation indicators, whereas more developed regions showed lower vulnerability. Overall, the Index provides a practical tool to support territorial prioritization and targeted heat–health adaptation strategies in ageing populations.