Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China; State Key Laboratory of National Security Specially Needed Drug, Beijing Institute of Pharmacology & Toxicology, Beijing 100850, China.
Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China; State Key Laboratory of National Security Specially Needed Drug, Beijing Institute of Pharmacology & Toxicology, Beijing 100850, China.
Int J Biol Macromol. 2024 Aug;274(Pt 2):133500. doi: 10.1016/j.ijbiomac.2024.133500. Epub 2024 Jun 27.
In traditional Chinese medicine, Lycium barbarum is of rich medicinal value, and its polysaccharides are particularly interesting due to their significant pharmacological effects and potential health benefits. This study investigated the immunomodulatory effects of Lycium barbarum polysaccharides (LBPs) by examining their interaction with the TLR4/MD-2 complex and the impacts of gastrointestinal digestion on these interactions. We discovered that the affinity binding of LBPs for TLR4/MD-2 and their cytokine induction capability are influenced by molecular weight, with medium-sized LBPs (100-300 kDa) exhibiting stronger binding affinity and induction capability. Conversely, LBPs smaller than 10 kDa showed reduced activity. Additionally, the content of arabinose and galactose within the LBPs fractions was found to correlate positively with both receptor affinity and cytokine secretion. Simulated gastrointestinal digestion resulted in the degradation of LBPs into smaller fragments that are rich in glucose. Although these fragments exhibited decreased binding affinity to the TLR4/MD-2 complex, they maintained their activity to promote cytokine production. Our findings highlight the significance of molecular weight and specific monosaccharide composition in the immunomodulatory function of LBPs and emphasize the influence of gastrointestinal digestion on the effects of LBPs. This research contributes to a better understanding of the mechanisms underlying the immunomodulatory effects of traditional Chinese medicine polysaccharides and their practical application.
在中医药学中，枸杞具有丰富的药用价值，其多糖因其显著的药理作用和潜在的健康益处而备受关注。本研究通过考察枸杞多糖（LBPs）与 TLR4/MD-2 复合物的相互作用以及胃肠道消化对这些相互作用的影响，研究了枸杞多糖的免疫调节作用。我们发现，LBPs 与 TLR4/MD-2 的亲和力结合及其细胞因子诱导能力受分子量影响，中分子量 LBPs（100-300 kDa）表现出更强的结合亲和力和诱导能力。相比之下，小于 10 kDa 的 LBPs 活性降低。此外，LBPs 各馏分中的阿拉伯糖和半乳糖含量与受体亲和力和细胞因子分泌呈正相关。模拟胃肠道消化导致 LBPs 降解成富含葡萄糖的较小片段。尽管这些片段与 TLR4/MD-2 复合物的结合亲和力降低，但它们仍保持促进细胞因子产生的活性。我们的研究结果强调了分子量和特定单糖组成在 LBPs 免疫调节功能中的重要性，并强调了胃肠道消化对 LBPs 作用的影响。这项研究有助于更好地理解中药多糖免疫调节作用的机制及其实际应用。
