Arteriolar degeneration and stiffness in cerebral amyloid angiopathy are linked to ß-amyloid deposition and lysyl oxidase.

Cerebral amyloid angiopathy (CAA) is a vasculopathy characterized by vascular ß-amyloid (Aß) deposition on cerebral blood vessels. CAA is closely linked to Alzheimer's disease (AD) and intracerebral hemorrhage. CAA is associated with the loss of autoregulation in the brain, vascular rupture, and cognitive decline. To assess morphological and molecular changes associated with the degeneration of penetrating arterioles in CAA, we analyzed post-mortem human brain tissue from 26 patients with mild, moderate, and severe CAA end neurological controls. The tissue was optically cleared for three-dimensional light sheet microscopy, and morphological features were quantified using surface volume rendering. We stained Aß, vascular smooth muscle (VSM), lysyl oxidase (LOX), and vascular markers to visualize the relationship between degenerative morphological features, including vascular dilation, dolichoectasia (variability in lumenal diameter) and tortuosity, and the volumes of VSM, Aß, and LOX in arterioles. Atomic force microscopy (AFM) was used to assess arteriolar wall stiffness, and we identified a pattern of morphological features associated with degenerating arterioles in the cortex. The volume of VSM associated with the arteriole was reduced by around 80% in arterioles with severe CAA and around 60% in cases with mild/moderate CAA. This loss of VSM correlated with increased arteriolar diameter and variability of diameter, suggesting VSM loss contributes to arteriolar laxity. These vascular morphological features correlated strongly with Aß deposits. At sites of microhemorrhage, Aß was consistently present, although the morphology of the deposits changed from the typical organized ring shape to sharply contoured shards with marked dilation of the vessel. AFM showed that arteriolar walls with CAA were more than 400% stiffer than those without CAA. Finally, we characterized the association of vascular degeneration with LOX, finding strong associations with VSM loss and vascular degeneration. These results show an association between vascular Aß deposition, microvascular degeneration, and increased vascular stiffness, likely due to the combined effects of replacement of VSM by ß-amyloid, cross-linking of extracellular matrices (ECM) by LOX, and possibly fibrosis. This advanced microscopic imaging study clarifies the association between Aß deposition and vascular fragility. Restoration of physiologic ECM properties in penetrating arteries may yield a novel therapeutic strategy for CAA.

Detection, Visualization and Quantification of Protein Complexes in Human Alzheimer's Disease Brains using Proximity Ligation Assay.

Examination of healthy and diseased human brain is essential to translational neuroscience. Protein-protein interactions play a pivotal role in physiological and pathological processes, but their detection is difficult, especially in aged and fixed human brain tissue. We used the proximity ligation assay (PLA) to broaden the range of molecular interactions assessable in-situ in human neuropathology. We adapted fluorescent in-situ PLA to detect ubiquitin-modified proteins in human brains with Alzheimer's disease (AD), including approaches for the management of autofluorescence and quantification using a high-content image analysis system. We confirmed that hyperphosphorylated microtubule-associated protein tau (Serine202, Threonine205) aggregates were modified by ubiquitin and that phospho-tau-ubiquitin complexes were increased in hippocampal and frontal cortex regions in AD compared to non-AD brains. Overall, we refined PLA for use in human neuropathology, which has revealed a profound change in the distribution of ubiquitin in AD brain and its association with characteristic tau pathologies.

Detection, visualization and quantification of protein complexes in human Alzheimer's disease brains using proximity ligation assay.

Examination of healthy and diseased human brain is essential to translational neuroscience. Protein-protein interactions play a pivotal role in physiological and pathological processes, but their detection is difficult, especially in aged and fixed human brain tissue. We used the in-situ proximity ligation assay (PLA) to broaden the range of molecular interactions assessable in-situ in the human neuropathology. We adapted fluorescent in-situ PLA to detect ubiquitin-modified proteins in human brains with Alzheimer's disease (AD), including approaches for the management of autofluorescence and quantification using a high-content image analysis system. We confirmed that phosphorylated microtubule-associated protein tau (Serine202, Threonine205) aggregates were modified by ubiquitin and that phospho-tau-ubiquitin complexes were increased in hippocampal and frontal cortex regions in AD compared to non-AD brains. Overall, we refined PLA for use in human neuropathology, which has revealed a profound change in the distribution of ubiquitin in AD brain and its association with characteristic tau pathologies.

Medio de cultivo convencional enriquecido con extractos de quinoa, amaranto y chía promueve el crecimiento de Staphylococcus aureus / Conventional culture media enriched with extracts of quinoa, amaranth and chia promotes the Staphylococcus aureus growth

La identificación bacteriana durante las infecciones microbiológicas es un aspecto crítico a la hora de escoger un tratamiento específico para evitar complicaciones del paciente o en algunos casos su muerte. Por ello, incrementar el crecimiento celular durante el diagnóstico clínico por cultivo bacteriano puede reducir el tiempo para determinar el patógeno que causa la enfermedad. En este trabajo, se utilizó el cultivo bacteriano como metodología y se evaluó el crecimiento de Staphylococcus aureus en un medio de cultivo convencional enriquecido con extractos de Chenopodium quinoa, Amaranthus caudatus y Salvia hispanica. Los resultados obtenidos muestran que estos extractos, a bajas concentraciones, tienen un efecto protector contra la citotoxicidad que se podría generar por el estrés oxidativo producto del metabolismo celular de las bacterias cultivadas in vitro e incrementan significativamente el crecimiento bacteriano. La adicción de estos extractos a los medios convencionales podría mejorar el crecimiento bacteriano durante un diagnóstico bacteriológico y reducir el tiempo de identificación del patógeno.

Increasing the bacterial growth rate reduces the time getting the bacteria identification. This is helpful to choose an accurate and quick therapeutic strategy during microbiological infections, avoiding illness complications or in some cases the death. Here, we used bacterial growth method and we evaluated the growth of Staphylococcus aureus including an extract of Chenopodium quinoa, Amaranthus caudatus and Salvia hispanica in the routine culture media. Results show that adding these extracts, at low concentrations, have a protective effect against the cytotoxicity that could be generated by the oxidative stress product of the cellular metabolism of the bacteria growing in vitro and significantly increase the bacterial growth. The addition of these extracts to conventional culture media could improve bacterial growth during a bacteriological diagnosis and to reduce the time of pathogen identification.