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The preparation of pH-responsive nanocontainers by typical silane modification of the mesoporous silica nanoparticle (MSN) surface is usually high-cost, complex, and time-consuming, which remains a great challenge for effective corrosion protection of magnesium alloy. Here, a new strategy to construct pH-responsive nanocontainers (MSN-MBT@LDH) is demonstrated. The nanocontainers consist of corrosion inhibitor (2-mercaptobenzothiazole, MBT) loaded MSN core and layered double hydroxide (LDH) nanosheet shell serving as gatekeepers. The successful loading of MBT and encapsulation by LDH nanosheets were confirmed by a series of characterization such as scanning transmission electron microscopy coupled with energy dispersive X-ray spectroscopy (STEM-EDS) and N2 adsorption/desorption isotherms. The pH-responsive feature of the nanocontainers was demonstrated by determination of the MBT concentration in buffer solutions with different pH values. A smart corrosion protection system on Mg alloy is obtained by incorporating the synthesized nanocontainers into a self-assembled nanophase particle (SNAP) coating. The electrochemical tests and visual observations show that the hybrid coating has the best barrier properties and robustness in corrosion protection in NaCl corrosive solutions in comparison with the control coatings. The present method simplifies the synthesis processes of nanocontainers and eliminates the potential detrimental effect of excess gatekeepers on the coating. The findings provide new insights into the preparation of scalable nanocontainers. The self-healing coatings are expected to have widespread applications for corrosion protection of Mg alloy and other metals.

Sirtuin 1 (SIRT1) is a critical suppressor of T cell immunity. However, whether SIRT1 is involved in the progression of acute graft-vs.-host disease (aGVHD) has still remained unclear. PI3K/Akt/mTOR pathway is a crucial element involved in the activation and functions of T cells. Over-activation of PI3K/Akt/mTOR signaling may be related to the occurrence of aGVHD. STAT3 activation requires phosphorylation and acetylation. A recent study showed that STAT3 hyperphosphorylation in CD4+ T cells may be a trigger of aGVHD. The role of the STAT3 acetylation in aGVHD pathogenesis is still unclear. The present study revealed that SIRT1 deficiency as a critical factor is involved in the excessive activation of mTOR pathway and upregulation of STAT3 acetylation and phosphorylation in CD4+ T cells from patients with aGVHD. Exorbitant activation of IL-1β signaling is the main reason for TAK1-dependent SIRT1 insufficiency. The findings of the present study might provide a new therapeutic target for treating aGVHD.

To explore the anti-inflammatory mechanism of Camellia oleifera seed oil, the metabolites in ethanol extracts from 15 batches of C. oleifera seeds were analyzed by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and the inhibitory activity of the ethanol extracts on enteritis in Drosophila was evaluated by the “Smurf” test. The correlation between small molecular metabolites in the ethanol extracts and their anti-inflammatory activity was investigated and molecular docking with lipoxidase (LOX) was conducted to identify the key metabolites. Finally, the key metabolites were verified by the “Smurf” test. The results showed that the ethanol extract of C. oleifera seeds had good enteritis inhibitory activity, with percentage inhibition of 15.06%–61.71%, and its metabolites mainly included polyphenols, amino acids, organic acids, nucleotides, sugars and lipids. Seven polyphenolic compounds were identified in C. oleifera seeds for the first time. The monomeric compounds with good anti-enteritis activity were preliminarily identified as bruceine B, miltirone, 8-geranyloxypsoralen, cedrelone, wighteone, kaempferitrin and kaempferol-3-O-rutinoside. The anti-inflammatory activity of wighteone was reported for the first time in this study, and at 0.1 mg/mL, the percentage inhibition of enteritis was 64%, much greater than the positive control sulfasalazine (27.99%). This study lays the foundation for further exploring the anti-enteritis activity and mechanism of C. oleifera seed oil in vitro and in vivo.