A neurodegenerative cellular stress response linked to dark microglia and toxic lipid secretion.

The brain's primary immune cells, microglia, are a leading causal cell type in Alzheimer's disease (AD). Yet, the mechanisms by which microglia can drive neurodegeneration remain unresolved. Here, we discover that a conserved stress signaling pathway, the integrated stress response (ISR), characterizes a microglia subset with neurodegenerative outcomes.

Microglia degrade Alzheimer's amyloid-beta deposits extracellularly via digestive exophagy.

How microglia digest Alzheimer's fibrillar amyloid-beta (Aβ) plaques that are too large to be phagocytosed is not well understood. Here, we show that primary microglial cells create acidic extracellular compartments, lysosomal synapses, on model plaques and digest them with exocytosed lysosomal enzymes. This mechanism, called digestive exophagy, is confirmed by electron microscopy in 5xFAD mouse brains, which shows that a lysosomal enzyme, acid phosphatase, is secreted toward the plaques in structures resembling lysosomal synapses.

Female mice exhibit similar long-term plasticity and microglial properties between the dorsal and ventral hippocampal poles.

The hippocampus is a heterogenous structure that exhibits functional segregation along its longitudinal axis. We recently showed that in male mice, microglia, the brain's resident immune cells, differ between the dorsal (DH) and ventral (VH) hippocampus, impacting long-term potentiation (LTP) mainly through the CX3CL1-CX3CR1 signaling. Here, we assessed the specific features of the hippocampal poles in female mice, demonstrating a similar LTP amplitude in VH and DH in both control and Cx3cr1 knock-out mice.

Enhancing indoor air quality: Harnessing architectural elements, natural ventilation and passive design strategies for effective pollution reduction - A comprehensive review.

Air pollution poses a critical global challenge with severe environmental and human health implications. The associated health risks, including premature mortality, underscore the urgency of effective mitigation strategies. Many studies focus on control strategies without considering specific contaminant types, and there is a notable gap in research on cost-effective, eco-friendly methods, especially in countries facing substantial air pollution challenges.