Alzheimer’s disease (AD), the most common form of dementia, is characterized by the accumulation of amyloid β (Aβ) and hyperphosphorylated tau protein aggregates. Importantly, Aβ and tau species are able to activate astrocytes and microglia, which release several proinflammatory cytokines, such as tumor necrosis factor α (TNF-α) and interleukin 1β (IL-1β), together with reactive oxygen (ROS) and nitrogen species (RNS), triggering neuroinflammation. However, this inflammatory response has a dual function: it can play a protective role by increasing Aβ degradation and clearance, but it can also contribute to Aβ and tau overproduction and induce neurodegeneration and synaptic loss. Due to the significant role of inflammation in the pathogenesis of AD, several inflammatory mediators have been proposed as AD markers, such as TNF-α, IL-1β, Iba-1, GFAP, NF-κB, TLR2, and MHCII. Importantly, the use of anti-inflammatory drugs such as NSAIDs has emerged as a potential treatment against AD. Moreover, diseases related to systemic or local inflammation, including infections, cerebrovascular accidents, and obesity, have been proposed as risk factors for the development of AD. In the following review, we focus on key inflammatory processes associated with AD pathogenesis.

Scheme1.Schematicdiagram of laccase catalysis. Generalrepresentation of laccase-catalyzedredox cycles for substrate oxidation, with 2,6-dimethoxyphenol (2,6-DMP) as am odel substrate (SUB).

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Phytases are phosphohydrolases that initiate the sequential hydrolysis of phosphate from phytate, which is the main storage form of phosphorous in numerous plant seeds, especially in cereals and grains. Phytate is indigestible for most monogastric animals, such as poultry, swine, fish, and humans; therefore, microbial phytases have been widely used in plant (specially soy)-based animal feeding to improve nutrition by enhanced phosphorus, mineral, and trace element absorption, and reducing phosphorus pollution by animal waste. Most phytases used as animal feed additives have an acid pH optimum (pH 2.5 and 5.5 for Aspergillus and pH 4.5 for E. coli phytases) and show a sharp decrease in performance at neutral pH, correlating with intestinal digestion. Directed evolution of phytases has been previously reported to improve enzyme thermostability, pH, or specific activity. In this manuscript, we report a directed evolution campaign of the highly active bacterial phytase from Yersinia mollaretii (YmPh) towards a broadened pH activity spectrum. Directed evolution identified the key positions T44 and K45 for increased YmPh activity at neutral pH. Both positions are located in the active site loop of the phytase and have a synergistic effect on activity with a broadened pH spectrum. Kinetic characterization of the improved variants, YmPh-M10 and -M16, showed up to sevenfold increased specific activity and up to 2.2-fold reduced K at pH 6.6 under screening conditions compared to Yersinia mollaretii phytase wild type (YmPhWT).

El orégano (Origanum vulgare L.) es una especie introducida en la flora ecuatoriana. Por sus propiedades es muy apreciada y consumida, por lo que es importante determinar la naturaleza de sus beneficios. En este estudio se evaluó la composición fisicoquímica y el contenido de los compuestos funcionales responsables de la actividad antioxidante de la planta en la accesión ECU-20229 del Banco de Germoplasma del Instituto Nacional de Investigaciones Agropecuarias (INIAP). El estudio se realizó en Italquí provincia de Imbabura y en Tumbaco provincia de Pichincha. Se analizó la planta entera y sus partes (raíz, tallo y hojas), con la finalidad de determinar dónde se encuentra el mayor contenido de proteína, grasa, minerales y los compuestos funcionales. Se realizó el análisis proximal, concentración de proteína, minerales, polifenoles y flavonoides totales, así como la capacidad antioxidante. El contenido de los compuestos analizados fue estadísticamente diferentes entre las partes de la planta analizadas, y entre los sitios estudiados. La concentración de proteína, grasa y carbohidratos fue superior en las hojas que en las otras partes de la planta. La concentración de estos compuestos fue mayor en Tumbaco que en Italquí. Los macro y microminerales se encontraron en mayor cantidad en Italquí, al igual que el contenido de polifenoles y flavonoides totales. La capacidad de antioxidante fue mayor en Tumbaco. En este estudio se han confirmado las propiedades nutritivas descritas para esta planta en beneficio de la salud humana y animal, pero además se aporta información sobre el valor agregado a las partes de la planta que regularmente son desaprovechadas.