我們攝取的 NMN 真的能被身體有效利用嗎？
In the field of anti-aging, NMN (nicotinamide mononucleotide) has long been a highly regarded “star molecule.” As a direct precursor of NAD⁺, it shows great potential in energy metabolism, DNA repair, 和 anti-aging. However, a long-st和ing question troubling both researchers 和 consumers is: 口服摄入的NMN真的能被人体有效利用吗？
近期，一项发表于国际权威期刊 Food & Function provided a breakthrough answer. By employing an innovative “liposomal microgel” technology, scientists successfully overcame key bottlenecks such as poor absorption 和 low stability of NMN, significantly enhancing its protective effects in vivo.
传统NMN面临的最大挑战在于其水溶性特性，导致肠道吸收率低且代谢迅速。研究团队采用了薄膜超声法制备的脂质体包封技术。扫描电子显微镜显示，负载LYC和NMN的微凝胶呈现出均匀的多孔海绵状结构，脂质体以球形或椭球形均匀分布，有效填充了微凝胶的内部空腔。
In stability tests, free NMN completely degraded within 12 hours at 80°C. In contrast, NMN encapsulated in microgels showed significantly improved stability under both acidic 和 alkaline conditions. Notably, in simulated gastrointestinal digestion experiments, more than 80% of encapsulated NMN remained after 4 hours, demonstrating its ability to resist gastric acid degradation 和 achieve targeted intestinal release.
体外释放实验揭示了脂质体NMN的智能释放行为。在模拟胃液（SGF，pH = 2.0）中，NMN的释放率被控制在20%以下，而在模拟肠液（SIF，pH = 7.5）中，释放率超过80%。这种pH依赖性释放确保了NMN在胃中避免降解，并在肠道的最佳吸收位点释放。
粒径和Zeta电位分析显示，CS-NMN-BLP微凝胶的平均粒径为1668.33 nm，Zeta电位为-30.03 mV。Zeta电位绝对值超过30表明系统稳定性良好，为NMN在消化过程中提供了物理保护。
研究还发现，脂质体NMN微凝胶显著改善了肠道菌群组成。在LPS诱导的小鼠模型中，微凝胶干预增加了厚壁菌门与拟杆菌门的比例，并促进了有益菌如 罗斯氏菌属 和 Ruminococcus的富集。这些微生物产生短链脂肪酸，进一步增强肠道屏障功能，并间接提高NMN的吸收效率。
In an LPS-induced acute liver injury model, liposomal NMN microgels demonstrated significant protective effects. Compared with the model group, the CS-NMN-BLP treatment group showed markedly reduced levels of inflammatory factors such as TNF-α, IL-6, 和 IL-1β in serum. Meanwhile, antioxidant enzyme activities (SOD 和 GSH-px) in the liver increased significantly, while MDA levels decreased.
组织病理学检查进一步表明，微凝胶治疗有效减轻了肝细胞坏死、炎症细胞浸润和空泡变性。
参考文献：
Ge, J., et al. (2024). Preparation of microgels loaded with lycopene/NMN 和 their protective mechanism against acute liver injury. Food & Function, *15*(2), 809–822. https://doi.org/10.1039/d3fo03293k
近期，一项发表于国际权威期刊 Food & Function provided a breakthrough answer. By employing an innovative “liposomal microgel” technology, scientists successfully overcame key bottlenecks such as poor absorption 和 low stability of NMN, significantly enhancing its protective effects in vivo.
第一部分
A “Smart Armor” for Molecules: No More “Naked” NMN
传统NMN面临的最大挑战在于其水溶性特性，导致肠道吸收率低且代谢迅速。研究团队采用了薄膜超声法制备的脂质体包封技术。扫描电子显微镜显示，负载LYC和NMN的微凝胶呈现出均匀的多孔海绵状结构，脂质体以球形或椭球形均匀分布，有效填充了微凝胶的内部空腔。
In stability tests, free NMN completely degraded within 12 hours at 80°C. In contrast, NMN encapsulated in microgels showed significantly improved stability under both acidic 和 alkaline conditions. Notably, in simulated gastrointestinal digestion experiments, more than 80% of encapsulated NMN remained after 4 hours, demonstrating its ability to resist gastric acid degradation 和 achieve targeted intestinal release.
第二部分
智能靶向释放：在肠道中精准吸收
体外释放实验揭示了脂质体NMN的智能释放行为。在模拟胃液（SGF，pH = 2.0）中，NMN的释放率被控制在20%以下，而在模拟肠液（SIF，pH = 7.5）中，释放率超过80%。这种pH依赖性释放确保了NMN在胃中避免降解，并在肠道的最佳吸收位点释放。
粒径和Zeta电位分析显示，CS-NMN-BLP微凝胶的平均粒径为1668.33 nm，Zeta电位为-30.03 mV。Zeta电位绝对值超过30表明系统稳定性良好，为NMN在消化过程中提供了物理保护。
第三部分
Gut Microbiota Modulation: The “Hidden Bonus” of NMN
研究还发现，脂质体NMN微凝胶显著改善了肠道菌群组成。在LPS诱导的小鼠模型中，微凝胶干预增加了厚壁菌门与拟杆菌门的比例，并促进了有益菌如 罗斯氏菌属 和 Ruminococcus的富集。这些微生物产生短链脂肪酸，进一步增强肠道屏障功能，并间接提高NMN的吸收效率。
第四部分
功效验证：减轻炎症并增强抗氧化能力
In an LPS-induced acute liver injury model, liposomal NMN microgels demonstrated significant protective effects. Compared with the model group, the CS-NMN-BLP treatment group showed markedly reduced levels of inflammatory factors such as TNF-α, IL-6, 和 IL-1β in serum. Meanwhile, antioxidant enzyme activities (SOD 和 GSH-px) in the liver increased significantly, while MDA levels decreased.
组织病理学检查进一步表明，微凝胶治疗有效减轻了肝细胞坏死、炎症细胞浸润和空泡变性。
参考文献：
Ge, J., et al. (2024). Preparation of microgels loaded with lycopene/NMN 和 their protective mechanism against acute liver injury. Food & Function, *15*(2), 809–822. https://doi.org/10.1039/d3fo03293k
