Carbon dots(CDs),nanoscale carbon-based particles ubiquitously present in thermally processed foods such as toasted products,exhibit exceptional structural stability even after gastrointestinal digestion,a property th...Carbon dots(CDs),nanoscale carbon-based particles ubiquitously present in thermally processed foods such as toasted products,exhibit exceptional structural stability even after gastrointestinal digestion,a property that facilitates their systemic absorption and bioaccumulation.Their persistence in biological systems enables direct interactions with small bioactive molecules,potentially modulating the functional properties of dietary components.This study systematically evaluates the impact of CDs on the antioxidant efficacy of tea polyphenols(TPs),a class of natural antioxidants widely recognized for their health-promoting effects.The structure,antioxidant capacity,and in vitro cytological effects of the CDs-TPs complex were also investigated.Our results demonstrate that CDs and TPs form stable complexes mediated by non-covalent interactions,with hydrogen bonding identified as the dominant mechanism–specifically between the phenolic hydroxyl groups of TPs and fluorescent carbon-rich domains on CDs.These interactions induced a concentration-dependent enhancement in fluorescence intensity,with optimal binding efficiency observed at low CDs/TPs molar ratios(1:1 and 10:1).Structural analyses revealed that TP binding altered the tertiary conformation of CDs,exposing additional luminescent sites and modifying surface charge distribution.Transcriptomic profiling further demonstrated dose-dependent increases in differentially expressed genes under higher CDs/TPs ratios,which were predominantly enriched in oxidative stress response pathways.Mechanistic studies identified the FoxO signaling pathway as a central regulatory axis,with CDs-TPs complexes modulating the expression of antioxidant-related genes(e.g.,SOD2)and downstream effectors involved in redox homeostasis.These findings not only elucidate the structure-function interplay governing CDs-TPs interactions,but also highlight their dual role as modulators of antioxidant activity and potential therapeutic agents,establishing a foundation for developing CD-based composite materials in targeted antioxidant therapies.展开更多
基金supported by the National Key Research and Development Program of China(No.2024 YFD2401602)the National Natural Science Foundation of China(No.32302209)+4 种基金the Natural Science Foundation of Zhejiang Province(No.LQ24C200001)the Young Science and Technology Innovation Leading Talents of Ningbo City(No.2023QL038)the Natural Science Foundation of Ningbo(No.2023J104)the Zhejiang Provincial Department of Education General Project(Nos.Y202248913,Y202248913)the General Project of Education Department of Zhejiang Province(No.Y202353405)。
文摘Carbon dots(CDs),nanoscale carbon-based particles ubiquitously present in thermally processed foods such as toasted products,exhibit exceptional structural stability even after gastrointestinal digestion,a property that facilitates their systemic absorption and bioaccumulation.Their persistence in biological systems enables direct interactions with small bioactive molecules,potentially modulating the functional properties of dietary components.This study systematically evaluates the impact of CDs on the antioxidant efficacy of tea polyphenols(TPs),a class of natural antioxidants widely recognized for their health-promoting effects.The structure,antioxidant capacity,and in vitro cytological effects of the CDs-TPs complex were also investigated.Our results demonstrate that CDs and TPs form stable complexes mediated by non-covalent interactions,with hydrogen bonding identified as the dominant mechanism–specifically between the phenolic hydroxyl groups of TPs and fluorescent carbon-rich domains on CDs.These interactions induced a concentration-dependent enhancement in fluorescence intensity,with optimal binding efficiency observed at low CDs/TPs molar ratios(1:1 and 10:1).Structural analyses revealed that TP binding altered the tertiary conformation of CDs,exposing additional luminescent sites and modifying surface charge distribution.Transcriptomic profiling further demonstrated dose-dependent increases in differentially expressed genes under higher CDs/TPs ratios,which were predominantly enriched in oxidative stress response pathways.Mechanistic studies identified the FoxO signaling pathway as a central regulatory axis,with CDs-TPs complexes modulating the expression of antioxidant-related genes(e.g.,SOD2)and downstream effectors involved in redox homeostasis.These findings not only elucidate the structure-function interplay governing CDs-TPs interactions,but also highlight their dual role as modulators of antioxidant activity and potential therapeutic agents,establishing a foundation for developing CD-based composite materials in targeted antioxidant therapies.
