Ginsenoside Rb1 protects hippocampal neurons in depressed rats based on mitophagy-regulated astrocytic pyroptosis.

BACKGROUND: Astrocytes play a vital role in offering functional support for neurons, which are related to the pathogenic mechanism of depression. Ginsenoside Rb1 (GRb1) is demonstrated with antidepressant-like activities. PURPOSE: We aimed to investigate whether GRb1 can inhibit mitophagy-mediated astrocytic pyroptosis to protect neurons in depression. STUDY DESIGN: Model rats were subjected to chronic unpredictable mild stress (CUMS) for determining the in vivo antidepressant activity of GRb1. METHODS: The mitophagy-mediated antipyroptosis role of GRb1 was assessed in lipopolysaccharide (LPS) + ATP-stimulated astrocytes. The mechanism by which GRb1 protects synaptic plasticity was investigated using hippocampal neurons incubated in an astrocyte medium. The rat depressive-like behaviors were determined through sucrose preference, forced swimming, and the open-field tests. Escitalopram was used in the anti-depression control of GRb1. Cyclosporin A (CsA), a mitophagy inhibitor, and interleukin (IL)-1ß were used to reverse the role of GRb1 in mitophagy and pyroptosis, respectively. RESULTS: GRb1 inhibited LPS-induced inflammation and activation in the astrocytes and repressed nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway. Also, GRb1 repressed LPS + ATP-promoted astrocytic pyroptosis. During GRb1 treatment, the activation of mitophagy with a decrease in ROS was observed in LPS + ATPs-stimulated astrocytes. CsA enhanced GRb1-decreased ROS and promoted astrocytic pyroptosis. The GRb1-treated astrocyte medium suppressed neuron death and increased neuron viability and synaptic density. Escitalopram and GRb1 improved the depressive-like behaviors of the rats. GRb1 activated mitophagy and inhibited astrocytic activation and pyroptosis in rats with depression. It also reduced impairments in synaptic structures and increased synaptic density in depressive-like rats. IL-1ß increased astrocytic pyroptosis and reversed GRb1-enhanced synaptic plasticity in the rats exposed to CUMS. There were no statistical changes in depressive-like behaviors between GRb1 and Escitalopram groups. CONCLUSION: GRb1 modulates mitophagy and the NF-κB pathway to inhibit astrocytic pyroptosis, thereby maintaining neurological homeostasis by repressing inflammation and enhancing synaptic plasticity.

Tannic acid-assisted fabrication of antibacterial sodium alginate-based gel beads for the multifunctional adsorption of heavy metal ions and dyes.

The existence of heavy metals and dyes seriously affects the ecological environment and human safety. Antibacterial adsorption materials with the broad-spectrum removal of multiple pollutants are urgently required for water remediation. Herein, a sustainable and antibacterial sodium alginate (SA) gel bead adsorbent with honeycomb cellular architecture is developed by the biomimetic deposition polyphenolic tannic acid (TA) induced grafting diethylenetriamine (DETA) under mild conditions for efficient removal of Cr(VI) and dyes. Taking advantage of the catechol surface chemistry, TA occurring rapid polymerization with DETA monomers not only enhances the water resistance and thermal stability of the gel bead, but also introduces abundant polyphenolic functional groups and active adsorption sites. The multifunctional gel bead showed outstanding antibacterial activity against S. aureus (sterilization rates: 83.8 %) and E. coli (sterilization rates: 99.5 %). The maximum adsorption capacity of gel bead for Cr(VI) was 163.9 mg/g. Moreover, the removal efficiency of the gel bead for dyes of Safranine T and Rhodamine B was 89.5 % (maximum adsorption capacity: 537 mg/g) and 76.7 % (maximum adsorption capacity: 460.2 mg/g), respectively, indicating its excellent broad-spectrum adsorption performance for multiple pollutants. Therefore, TA-assisted fabrication of SA-based gel bead with excellent antibacterial property is a promising multifunctional adsorption material for practical water remediation.

Noval green sodium alginate/gellan gum aerogel with 3D hierarchical porous structure for highly efficient and selective removal of Congo red from water.

Rational design of adsorbed materials with three-dimensional (3D) hierarchical porous structure, sustainable, high adsorption capacity, and excellent selective is of great significance in practical applications. Herein, a novel aerogel adsorbed material with 3D hierarchical porous architecture was fabricated by employing naturally abundant sodium alginate (SA)/gellan gum (GG) as basic construction blocks to achieve sustainability as well as applying polyethyleneimine (PEI) as functional material for highly efficient and selective capture of Congo red (CR). The aerogel sorbent exhibited strong microstructure, numerous active adsorption sites and being ultralight. The resulting aerogel adsorbent showed high adsorption capacity (3017.23 mg/g) toward CR, exceedingly most previously reported sorbents. Furthermore, the aerogel adsorbent was accompanied by outstanding selectivity for CR in four binary dye systems. Meanwhile, after 3 cycles, the adsorption capacity decreased by 14.8 %, but still maintained the adsorption capacity of 559.79 mg/g. Therefore, excellent adsorption performance, and superb selectivity prefigures its great prospects for wastewater purification.

Antidepression of Xingpijieyu formula targets gut microbiota derived from depressive disorder.

OBJECTIVE: This investigation aims to determine the antidepressant role of Xingpijieyu formula (XPJYF) mediated via gut microbiota (GM)-brain axis. METHODS: We collected fecal microbiota from patients with depressive disorder (DD) and cultured microbiota in vitro. Some of microbiota were transplanted into germ-free rats with the intragastric administration of XPJYF grain at the dose of 1.533 g/kg/day. The behaviors were studied by forced swimming test, open field test, sucrose preference test, and body weight. Products of hypothalamus-pituitary-adrenocortical (HPA) axis, neurotransmitter, and serum cytokines were investigated by enzyme linked immunosorbent assay. Glial fibrillary acidic protein (GFAP), a biomarker of astrocyte, was quantified using immunofluorescence. Microbiota culturing in vitro after XPJYF treatment was analyze by 16 s RNA sequencing technology. We used lipopolysaccharide (LPS) to mimic activated rat primary astrocyte in vitro. Brain-derived neurotrophic factor (BDNF), cytokines, and oxidative stress factors were determined by western blotting, and glycometabolism in astrocyte was investigated by 2-deoxy-D-glucose (2-DG) uptake, adenosine triphosphate (ATP), and glucose-1-phosphate (G1P) kits. RESULTS: Microbiota composition during 8 mg/ml of XPJYF (H12-8) for 12 h showed the more consistency. Lactococcus is enriched in DD-derived microbiota composition, and Biffdobacterium and Lactobacillus in H12-8 group. GLUCOSE1PMETAB-PWY and PWY-7328 of which biofunctions were dominantly encoded by Biffdobacterium were the top two of altered pathways. XPJYF improved behaviors and repressed astrocyte activation in depression rats. XPJYF elevated 2-DG uptake, ATP, glucose-1-phosphate, and brain-derived neurotrophic factor (BDNF), and inhibited cytokines and oxidative stress in LPS-induced astrocyte. CONCLUSION: XPJYF treatment targets inflammation, activation, and glycometabolim in astrocyte via gut microbiota modulation, thereby improve animal behaviors, HPA axis dysfunction, and neurotransmitter synthesis in depression rats.

Double noncovalent network chitosan/hyperbranched polyethylenimine/Fe3+ films with high toughness and good antibacterial activity.

The application of pure chitosan films is significantly limited due to their poor mechanical properties. In this study, a novel type of chitosan/hyperbranched polyethylenimine (CHP) and chitosan/hyperbranched polyethylenimine/Fe3+ (CHPF) films with high toughness and good antibacterial activity were prepared through a noncovalent crosslinking method. From the tensile test results, the strain and toughness of the CHP film increased by 798.1% and 292.3%, respectively, compared with pure chitosan film, after the addition of 20% hyperbranched polyethylenimine (HPEI). The addition of trace metal iron ions (3 mg) forms a metal coordination bond with the amine group on HPEI, as well as the hydroxyl group and amine group on chitosan, and develops a double noncovalent bond network structure with hydrogen bonding, which further enhances the mechanical tensile strength of the chitosan-based film, with an increase of 48.4%. Interestingly, HPEI and Fe3+ can be used as switches to increase and decrease the fluorescence property of chitosan, respectively. Furthermore, the CHP and CHPF films showed good antibacterial activity against S. aureus and E. coli.