Discovery of Active Ingredients Targeted TREM2 by SPR Biosensor-UPLC/MS Recognition System, and Investigating the Mechanism of Anti-Neuroinflammatory Activity on the Lignin-Amides from Datura metel Seeds

Abstract

As a new target protein for Alzheimer’s disease (AD), the triggering receptor expressed on myeloid Cells 2 (TREM2) was expressed on the surface of microglia, which was shown to regulate neuroinflammation, be associated with a variety of neuropathologic, and regarded as a potential indicator for monitoring AD. In this study, a novel recognition system based on surface plasmon resonance (SPR) for the TREM2 target spot was established coupled with quadrupole time-of-flight tandem mass spectrometry (UPLC-MS), in order to screen the active ingredients targeting TREM2 from Datura metel seeds. The results showed that four lignan-amides were discovered as candidate compounds by SPR biosensor-UPLC/MS recognition analysis. According to the guidance of the active ingredients discovered by the system, the lignin-amides from Datura metel seeds (LDS) were preliminarily identified as containing 27 lignan-amides, which were enriched compositions by the HP-20 of Datura metel seeds. Meanwhile, the anti-inflammatory activity of LDS was evaluated in BV2 microglia induced by LPS. Our experimental results demonstrated that LDS could reduce NO release in LPS-treated BV2 microglia cells and significantly reduce the expression of the proteins of inducible Nitric Oxide Synthase (iNOS), cyclooxygenase 2 (COX-2), microtubule-associated protein tau (Tau), and ionized calcium-binding adapter molecule 1 (IBA-1). Accordingly, LDS might increase the expression of TREM2/DNAX-activating protein of 12 kDa (DAP12) and suppress the Toll-like receptor SX4 (TLR4) pathway and Recombinant NLR Family, Pyrin Domain Containing Protein 3 (NLRP3)/cysteinyl aspartate specific proteinase-1 (Caspase-1) inflammasome expression by LDS in LPS-induced BV2 microglial cells. Then, the inhibitory release of inflammatory factors Interleukin 1 beta (IL-1β), Interleukin 6 (IL-6), and Tumor necrosis factor-alpha (TNFα) inflammatory cytokines were detected to inhibit neuroinflammatory responses. The present results propose that LDS has potential as an anti-neuroinflammatory agent against microglia-mediated neuroinflammatory disorders.

Ethnobotanical uses and phytochemical, biological, and toxicological profiles of Datura metel L.: A review

“… – Anti-cancer activity Maehara et al, 2020 Baimantuoluoline A Flower 50% Ethanol Showed the activity for psoriasis Yang et al, 2007 (5α,6β,7α,22R)-5,6,7,27- tetrahydroxy-1-oxowitha- 2,24-dien-27-O-β-D- glucopyranoside Flower Extracted with 70% Ethanol For treating of psoriasis Yang et al (2010b) 6,7-dimethyl-1-D-ribityl-quinoxaline-2,3(1H,4H) - dione-5′-O-β- Dglucopyranoside Flower Used 70% Ethanol Psoriasis treatment Yang et al (2010b) Sesquiterpenoid and aliphatic glycoside Roots 70% Ethanol Anti-inflammatory activity by 5 compounds Liu et al, 2022 (E)-methyl 4-(3-(4hydroxyphenyl) -N- methylacrylamido) butanoate Flower 70% Ethanol used for extraction Treatment of psoriasis Yang et al, 2010a Ergostane-type C28 sterols, daturmetesides A-E (1–5) Leaves 70% Ethanol Anti-inflammatory activity, IC 50 values ranging from 17.05 ± 0.35 μM to 24.88 ± 0.93. Tan et al, 2020b 1, 10-seco-withametelin B Flower Methanolic extraction Cytotoxicity is observed Pan et al, 2007 12 β -hydroxy-1,10-seco- withametelin B Flower Methanolic extraction Cytotoxicity is observed Pan et al, 2007 Alkaloid datumetine Leaves Para-methoxy benzoic acid Anti-spasmodic action Siddiqui et al, 1987 Lignin-amides from Datura metel seeds (LDS) Seeds 95% Ethanol Anti-neuroinflammatory, Alzheimer disorder Wang et al, 2021 2-(3,4-dimethyl-2,5-dihydro-1H-pyrrol-2-...…”

Inflammatory signaling pathways in the treatment of Alzheimer's disease with inhibitors, natural products and metabolites (Review)

“…In addition to pterostilbene, LDS is also able to ameliorate neuroinflammation through the NLRP3/caspase-1 pathway. Wang et al ( 217 ) found that LDS had anti-inflammatory activity in LPS-induced BV2 cells. Additionally, PPSR (PEG-PEI/siROCK2), a synthetic molecule used in gene therapy for AD, was found to inhibit the increase in IL-1β induced by LPS/Aβ in primary microglia through the NLRP3/caspase-1 pathway, thus exhibiting anti-inflammatory effects ( 218 ).…”

An Electrochemiluminescence Biosensor for the Detection of Alzheimer’s Tau Protein Based on Gold Nanostar Decorated Carbon Nitride Nanosheets

“…However, the CSF sampling route is difficult, expensive, and invasive, making it inconvenient for largescale or repetitive sampling in a long-time following disease progression or treatment efficacy. Human Tau protein is a promising serum biomarker for AD-that has gained significant attention for early and accurate molecular diagnostics [4][5][6][7]. However, the serum concentrations of Tau protein biomarkers are at the pg/mL level, and ultrahigh-sensitivity detection methods are in great demand for clinical applications.…”