Phytohormone Abscisic Acid Improves Spatial Memory and Synaptogenesis Involving NDR1/2 Kinase in Rats

The ameliorative effects and mechanisms of abscisic acid on learning and memory

Abscisic acid (ABA), a conserved hormone existing in plants and animals, not only regulates blood glucose and inflammation but also has good therapeutic effects on obesity, diabetes, atherosclerosis and inflammatory diseases in animals. Studies have shown that exogenous ABA can pass the blood-brain barrier and inhibit neuroinflammation, promote neurogenesis, enhance synaptic plasticity, improve learning, memory and cognitive ability in the central nervous system. At the same time, ABA plays a crucial role in significant improvement of Alzheimer's disease, depression, and anxiety. Here we review the previous research progress of ABA on the physiological effects and clinical application in the related diseases. By summarizing the biological functions of ABA, we aim to reveal the possible mechanisms of ameliorative function of ABA on learning and memory, to provide a theoretical basis that ABA as a novel and safe drug improves learning memory and cognitive impairment in central system diseases such as aging, neurodegenerative diseases and traumatic brain injury.

Amino acid motifs for the identification of novel protein interactants

Biological systems consist of multiple components of different physical and chemical properties that require complex and dynamic regulatory loops to function efficiently. The discovery of ever more novel interacting sites in complex proteins suggests that we are only beginning to understand how cellular and biological functions are integrated and tuned at the molecular and systems levels. Here we review recently discovered interacting sites which have been identified through rationally designed amino acid motifs diagnostic for specific molecular functions, including enzymatic activities and ligand-binding properties. We specifically discuss the nature of the latter using as examples, novel hormone recognition and gas sensing sites that occur in moonlighting protein complexes. Drawing evidence from the current literature, we discuss the potential implications at the cellular, tissue, and/or organismal levels of such non-catalytic interacting sites and provide several promising avenues for the expansion of amino acid motif searches to discover hitherto unknown protein interactants and interaction networks. We believe this knowledge will unearth unexpected functions in both new and well-characterized proteins, thus filling existing conceptual gaps or opening new avenues for applications either as drug targets or tools in pharmacology, cell biology and bio-catalysis. Beyond this, motif searches may also support the design of novel, effective and sustainable approaches to crop improvements and the development of new therapeutics.

Probiotic Lactobacillus rhamnosus GR-1 supplementation attenuates Pb-induced learning and memory deficits by reshaping the gut microbiota

Lead (Pb) exposure during early life has been associated with an increased risk of neurodevelopmental disorders, including learning and memory deficits. The intestinal flora, via the microbiome–gut–brain axis, could play a significant role in the nervous system. However, the effects of probiotics on ameliorating Pb-induced learning and memory deficits are still unclear. In this study, we showed that adolescent Pb exposure (150 ppm) for 2 months impaired spatial learning and memory ability, accompanied by the decreasing diversity of gut microbiota, and the decreasing abundance of Lactobacillus at the genus level. Surprisingly, administration of the Lactobacillus rhamnosus GR-1 (10¹⁰ organisms/rat/day), not L. rhamnosus LGG or Lactobacillus reuteri RC-14, reversed learning and memory deficits induced by Pb exposure. Meanwhile, administration of the L. rhamnosus GR-1 increased the diversity of the gut microbiota composition and partially normalized the genus level of Lactobacillus, Parabacteroides, Enterococcus, and Akkermansia in Pb-exposed rats. Notably, supplementation of L. rhamnosus GR-1 decreased the gut permeability of Pb-exposed rats, reduced proinflammatory cytokines [interleukin-1β (IL-1β) and IL-6] expression, and promoted anti-inflammatory cytokines [granulocyte colony-stimulating factor (G-CSF)] expression. Interestingly, neural cell treatment with G-CSF rescued Pb-induced neurotoxicity. In general, L. rhamnosus GR-1 supplementation recovered the Pb-induced loss of intestinal bacteria (Lactobacillus), which may have reversed the damage to learning and memory ability. Collectively, our findings demonstrate an unexpectedly pivotal role of L. rhamnosus GR-1 in Pb-induced cognitive deficits and identify a potential probiotic therapy for cognitive dysfunction during early life.

Fabrication of magnetic ordered mesoporous carbon for quantitative analysis of acidic phytohormones in mushroom samples prior to their determination by ultra-high-performance liquid chromatography–tandem mass spectrometry

A novel method was established for analysing trace four acidic phytohormones, namely, indole-3-acetic acid, 3-indolebutyric acid, abscisic acid, and 1-naphthylacetic acid, using magnetic ordered mesoporous carbon (MOMC). MOMC was facilely synthesised via self-assembly strategy with a direct carbonisation process. The properties of MOMC were characterised using various instruments. MOMC exhibited excellent adsorption capacity towards the analytes. Various critical parameters which may influence the enrichment efficiency were evaluated, including amount of MOMC, extraction conditions, and desorption conditions. An efficient method based on MOMC magnetic solid-phase extraction coupled with ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) was developed to analyse the trace four acidic phytohormones, with good correlation coefficients (R 2 = 0.9965–0.9998) and low limits of detection (0.13–9.7 ng L−1, S/N = 3). Trace acidic phytohormones in Agaricus bisporus and Hypsizygus marmoreus samples were determined with satisfactory recoveries (91.8–108%) and reproducibility (2.6–6.3%). The features indicated that MOMC provides an efficient platform for mushroom sampling; the developed method is convenient, promising, and sensitive for the detection of trace phytohormones in complicated mushroom samples.