Apoptosis is induced by sub-acute exposure to 3-MCPD and glycidol on Wistar Albino rat brain cells

Determination of Free Glycidol and Total Free Monochloropropanediol in Fish and Krill Oil with Simple Aqueous Derivatization and High-Performance Liquid Chromatography-Tandem Mass Spectrometry

This study introduces a novel method for detecting free glycidol and total free monochloropropanediol (MCPD) in fish and krill oil. Before analysis on high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS), p-(dimethylamino)phenol was used for derivatization of these compounds, enabling the sensitive determination of these contaminants. The sample preparation procedure includes a simple, efficient pretreatment using NaCl aqueous solution extraction and C18 sorbent cleanup (for demulsification), distinguishing glycidol from MCPD under varied reaction conditions for derivatization (weak acidic and strong alkaline aqueous environments). This approach shows broad linearity from 1 to at least 256 ng·mL-1, improved sensitivity compared to standard GC-MS methods, with the limit of detection (LOD) and limit of quantification (LOQ) for MCPD and glycidol in both oil samples verified at 0.5 ng·mL-1 and 1 ng·mL-1, respectively. Different from previous HPLC-MS methods for direct detection of glycidol esters or MCPD esters, this is the first HPLC-MS method used for the detection of free glycidol and total free MCPD in edible oil. Furthermore, this method can be potentially developed for glycidol or monochloropropane diol esters, which is similar to the current official methods adopted for indirect detection of these contaminants in different food matrices. Application of this detection method to real dietary supplements (fish oil and krill oil) revealed MCPD residues in fish oil (maximum detected: 32.78 ng·mL-1) and both MCPD (maximum detected: 2767.3 ng·mL-1) and glycidol (maximum detected: 22.2 ng·mL-1) in krill oil, emphasizing its effectiveness and accuracy for assessing contamination in these supplements.

Newly discovered developmental and ovarian toxicity of 3-monochloro-1,2-propanediol in Drosophila melanogaster and cyanidin-3-O-glucoside's protective effect

3-Monochloro-1,2-propanediol (3-MCPD) is a pervasive environmental pollutant that is unintentionally produced during industrial production and food processing. Although some studies reported the carcinogenicity and male reproduction toxicity of 3-MCPD thus far, it remains unexplored whether 3-MCPD hazards to female fertility and long-term development. In this study, the model Drosophila melanogaster was employed to evaluate risk assessment of emerging environmental contaminants 3-MCPD at various levels. We found that flies on dietary exposure to 3-MCPD incurred lethality in a concentration- and time-dependent way and interfered with metamorphosis and ovarian development, resulting in developmental retardance, ovarian deformity and female fecundity disorders. Mechanistically, 3-MCPD caused redox imbalance observed as a drastically increased oxidative status in ovaries, confirmed by increased reactive oxygen species (ROS) and decreased antioxidant activities, which is probably responsible for female reproductive impairments and developmental retardance. Intriguingly, these defects can be substantially prevented by a natural antioxidant, cyanidin-3-O-glucoside (C3G), further confirming a critical role of ovarian oxidative damage in the developmental and reproductive toxicity of 3-MCPD. The present study expanded the findings that 3-MCPD acts as a developmental and female reproductive toxicant, and our work provides a theoretical basis for the exploitation of a natural antioxidant resource as a dietary antidote for the reproductive and developmental hazards of environmental toxicants that act via increasing ROS in the target organ.

Apigenin and its octoic acid diester attenuated glycidol-induced autophagic-dependent apoptosis via inhibiting the ERK/JNK/p38 signaling pathways in human umbilical vein endothelial cells (HUVECs)

Glycidol is a well-known food contaminant mainly formed in refined edible oils and various thermally processed foods. Here, we studied the toxicity effects and related mechanism of glycidol on Human umbilical vein endothelial cells (HUVECs). Glycidol was found to induce Gap period 2 (G2)/Mitosis (M) phase cell cycle arrest, apoptosis, and autophagy in HUVECs. Inhibition of autophagy by 3-methyladenine (3-MA) attenuated glycidol-induced cell death, suggesting that glycidol-induced apoptosis was autophagy-dependent. Moreover, glycidol treatment induced phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal protein kinase (JNK), and p38. Inhibition of ERK, JNK, and p38 phosphorylation by the inhibitors U0126, SP600125, and SB203580 attenuated glycidol-induced autophagy and prevented glycidol-mediated reduction in cell viability, demonstrating that glycidol inhibited HUVECs growth by inducing autophagic-dependent apoptosis through activation of the ERK, JNK and p38 signaling pathways. In addition, apigenin (API) and its octoic acid diester apigenin-7 (API-C8), 4'-O-dioctanoate were found to significantly attenuate glycidol-induced cell growth inhibition by inhibiting the above signaling pathways. Collectively, glycidol induces autophagic-dependent apoptosis via activating the ERK/JNK/p38 signaling pathways in HUVECs and API-C8 could attenuate the toxicity effects.

Bibliometric Analysis of Research Trends on 3-Monochloropropane-1,2-Diol Esters in Foods

3-Monochloropropane-1,2-diol esters (3-MCPDE) are common food contaminants mainly formed in the edible oil refining process. Due to their potential hazards, 3-MCPDE has become a widespread food safety concern. In this study, CiteSpace and VOSviewer were used to conduct a bibliometric analysis on the 3-MCPDE research papers collected in the Web of Science Core Collection from 1998 to 2022. The results showed that the number of research publications on 3-MCPDE has increased rapidly since 2010. Analysis of the hotspots in 3-MCPDE studies showed that more attention has been paid to the exposure assessment, formation mechanism, detection methods, mitigation methods and toxicity, and toxicology of 3-MCPDE. Finally, the future trends of research on 3-MCPDE were analyzed and proposed. The mitigation methods and toxicology studies of 3-MCPDE are still the research hotspots in the future. In addition, nutritional intervention for 3-MCPDE toxicity will be an emerging trend.