A Rapid and Sensitive UHPLC-MS/MS Method for Determination of Chlorogenic Acid and Its Application to Distribution and Neuroprotection in Rat Brain

Rapid and simple fluorescent detection of chlorogenic acid in Aidi injection using aggregation-induced emission (AIE) nanoclusters

Chlorogenic acid (CGA) is a key component in Aidi injection, known for its anti-cancer properties and ability to reduce toxicity. Therefore, accurate detection of CGA levels in Aidi injection is essential for monitoring therapeutic efficacy and minimizing adverse effects. This study presents a rapid and simple fluorescent method for detecting CGA in Aidi injection using aggregation-induced emission (AIE) nanoclusters, i.e. D(-)-penicillamine (DPA)-capped bimetallic gold/copper nanoclusters (DPA-Au/CuNCs). Upon the addition of CGA, the aggregation state of DPA-Au/CuNCs was disrupted through hydrogen bond formation and ligand exchange, leading to fluorescence quenching. The prepared DPA-Au/CuNCs exhibited a rapid response time of 0.5 min, and demonstrated good sensitivity for CGA, with a limit of detection of 3.75 μg/mL, and a linear detection range of 12.5-200 μg/mL. This method was successfully applied for the analysis of CGA in Aidi injection and plasma with good recovery rates and minimal matrix effect, highlighting its potential for the applications in pharmaceutical products and clinical samples.

Antioxidant, Anti-Inflammatory and Pro-Differentiative Effects of Chlorogenic Acid on M03-13 Human Oligodendrocyte-like Cells

Chlorogenic acid (CGA), a polyphenol found mainly in coffee and tea, exerts antioxidant, anti-inflammatory and anti-apoptotic effects at the gastrointestinal level. However, although CGA is known to cross the blood-brain barrier (BBB), its effects on the CNS are still unknown. Oligodendrocytes (OLs), the myelin-forming cells in the CNS, are the main target in demyelinating neuroinflammatory diseases such as multiple sclerosis (MS). We evaluated the antioxidant, anti-inflammatory and anti-apoptotic roles of CGA in M03-13, an immortalized human OL cell line. We found that CGA reduces intracellular superoxide ions, mitochondrial reactive oxygen species (ROS) and NADPH oxidases (NOXs) /dual oxidase 2 (DUOX2) protein levels. The stimulation of M03-13 cells with TNFα activates the nuclear factor kappa-light-chain-enhancer of activated B cell (NF-kB) pathway, leading to an increase in superoxide ion, NOXs/DUOX2 and phosphorylated extracellular regulated protein kinase (pERK) levels. In addition, tumor necrosis factor alpha (TNF-α) stimulation induces caspase 8 activation and the cleavage of poly-ADP-ribose polymerase (PARP). All these TNFα-induced effects are reversed by CGA. Furthermore, CGA induces a blockade of proliferation, driving cells to differentiation, resulting in increased mRNA levels of myelin basic protein (MBP) and proteolipid protein (PLP), which are major markers of mature OLs. Overall, these data suggest that dietary supplementation with this polyphenol could play an important beneficial role in autoimmune neuroinflammatory diseases such as MS.