A Highly Sensitive and Selective Fluorescent Sensor for Folic Acid Detection Based on D-penicillamine Stabilized Ag/Cu Alloy Nanoclusters.

In this work, a highly sensitive and selective method for detecting folic acid (FA) was developed using D-penicillamine (DPA) stabilized Ag/Cu alloy nanoclusters (DPA@Ag/Cu NCs). The yellow emission of DPA@Ag/Cu NCs was found to be quenched upon the addition of FA to the system. The fluorescence intensity quenching value demonstrated a linear relationship with FA concentrations ranging from 0.01 to 1200 µM, with a limit of detection (LOD) of 5.3 nM. Furthermore, the detection mechanism was investigated through various characterization analyses, including high resolution transmission electron microscopy, fluorescence spectra, ultraviolet-visible absorption spectra, and fluorescence lifetime. The results indicated that the fluorescence quenching induced by FA was a result of electron transfer from FA to the ligands of DPA@Ag/Cu NCs. The selectivity of the FA sensor was also evaluated, showing that common amino acids and inorganic ions had minimal impact on the detection of FA. Moreover, the standard addition method was successfully applied to detect FA in human serum, chewable tablets and FA tablets with promising results. The use of DPA@Ag/Cu NCs demonstrates significant potential for detecting FA in complex biological samples.

[Study on HPLC Fingerprint of Yunvjian].

Objective: To establish the high performance liquid chromatography-fingerprint of Yunvjian. Methods: The method was established on a C18column( 250 mm × 4. 6 mm,5 µm),and the column temperature was 30 ℃. The mobile phase consisted of 0. 2%aqueous phosphoric acid-methanol in gradient elution and the flow rate was 1. 0 m L / min. The detection wavelength was 254 nm. Results: HPLC fingerprint of Yunvjian was established,and 17 characteristic peaks were contained in Yunvjian fingerprint. The peak5 was 5-hydroxy methyl furfural,peak 11 was mangiferin,peak 12 was verbascoside,peak 13 was ecdysterone,and peak 17 was methylophiopogonanone A. Conclusion: The method provides experimental evidence and logical proofs for determination of the effective components of Yunvjian.

Exploring the Anti-Inflammatory Effect of Tryptanthrin by Regulating TLR4/MyD88/ROS/NF-κB, JAK/STAT3, and Keap1/Nrf2 Signaling Pathways.

Tryptanthrin (TRYP) is the main active ingredient in Indigo Naturalis. Studies have shown that TRYP had excellent anti-inflammatory activity, but its specific mechanism has been unclear. In this work, the differentially expressed proteins resulting from TRYP intervention in LPS-stimulated RAW264.7 cells were obtained based on tandem mass tag proteomics technology. The anti-inflammatory mechanism of TRYP was further validated by a combination of experiments using the LPS-induced RAW264.7 cell model in vitro and the DSS-induced UC mouse model (free drinking 2.5% DSS) in vivo. The results demonstrated that TRYP could inhibit levels of NO, IL-6, and TNF-α in LPS-induced RAW264.7 cells. Twelve differential proteins were screened out. And the results indicated that TRYP could inhibit upregulated levels of gp91phox, p22phox, FcεRIγ, IKKα/ß, and p-IκBα and reduce ROS levels in vitro. Besides, after TRYP treatment, the health conditions of colitis mice were all improved. Furthermore, TRYP inhibited the activation of JAK/STAT3, nuclear translocation of NF-κB p65, and promoted the nuclear expression of Nrf2 in vitro and in vivo. This work preliminarily indicated that TRYP might suppress the TLR4/MyD88/ROS/NF-κB and JAK/STAT3 signaling pathways to exert anti-inflammatory effects. Additionally, TRYP could achieve antioxidant effects by regulating the Keap1/Nrf2 signaling pathway.

Mangiferin inhibited neuroinflammation through regulating microglial polarization and suppressing NF-κB, NLRP3 pathway.

Inflammation plays important roles in the progress of neurodegenerative diseases, such as Parkinson's disease and Alzheimer's disease. Microglia is responsible for the homeostasis of the central nervous system (CNS), and involved in the neuroinflammation. Therefore, it could be potential in treatment of neurodegenerative diseases to suppress the microglia-mediated neuroinflammation. Mangiferin, a major glucoside of xanthone in Anemarrhena Rhizome, has anti-inflammatory, anti-diabetes, and anti-oxidative properties. However, the effect of mangiferin on the inflammatary responses of microglia cells are still poorly understand. In this study, we investigated the mechanism by which mangiferin inhibited inflammation in LPS-induced BV2 microglia cells. BV2 cells were pretreatment with mangiferin followed by LPS stimulation. In vitro assays, NO and cytokines production were quantified. Western blot and immunocytochemistry were used to examine the effect of mangiferin on the polarization of BV2 cells and signaling pathway. The results showed that mangiferin treatment significantly reduced NO, IL-1ß, IL-6 and TNF-α production, also reduced the mRNA and protein of iNOS and COX-2, promoted the polarization of inflammatory toward anti-inflammatory, and inhibited activation of NF-κB and NLRP3 inflammasome. These data suggest that mangiferin has an anti-neuroinflammatory property via regulating microglia macrophage polarization and suppressing NF-κB and NLRP3 signaling pathway, and may act as a potential natural therapeutic candidate for neuroinflammatory diseases.