College of Chemistry and Pharmaceutical Engineering, Jilin Institute of Chemical Technology, Jilin, Jilin 132022, China; Graduate school, Jilin Institute of Chemical Technology, Jilin, Jilin 132022, China.
College of Chemistry and Pharmaceutical Engineering, Jilin Institute of Chemical Technology, Jilin, Jilin 132022, China.
Int J Biol Macromol. 2024 Nov;279(Pt 1):135116. doi: 10.1016/j.ijbiomac.2024.135116. Epub 2024 Aug 28.
This study aimed to optimize the extraction process of polysaccharides from Rosa laevigata Michx. (RLMP) using an ultrasound-microwave-assisted method and investigate its in vitro hypoglycemic activity. Key factors affecting RLMP yield were identified using a Plackett-Burman design, followed by a Box-Behnken design and response-surface methodology, to determine the optimal extraction conditions. RLMP was purified using DEAE-52 cellulose, yielding two homogeneous fractions: RLMP-1 and RLMP-2. Monosaccharide composition was analyzed by gas chromatography, and structural characterization of RLMP, RLMP-1, and RLMP-2 was performed using FT-IR, SEM, and TEM. Methylation analysis and NMR were used to elucidate the sugar-chain structure of RLMP-1. In vitro hypoglycemic activity analysis showed that RLMP improved the glucose consumption and glycogen synthesis and enhanced the activities of pyruvate kinase and hexokinase in IR-HepG2 cells. Moreover, RLMP significantly increased the activities of antioxidant enzymes, such as CAT, SOD, and GSH-Px and decreased those of ROS and MDA. Western blotting analysis confirmed that RLMP enhances glucose and lipid metabolism and reduces oxidative stress by activating the PI3K/Akt/GLUT-4 signaling pathway, thereby exerting its hypoglycemic effect. These findings suggest that RLMP is a promising candidate for developing novel antioxidant agents or hypoglycemic drugs.
本研究旨在利用超声-微波辅助法优化玫瑰茄多糖（RLMP）的提取工艺，并研究其体外降血糖活性。采用 Plackett-Burman 设计确定影响 RLMP 产量的关键因素，然后采用 Box-Behnken 设计和响应面法确定最佳提取条件。用 DEAE-52 纤维素对 RLMP 进行纯化，得到两个均一的组分：RLMP-1 和 RLMP-2。采用气相色谱法分析单糖组成，用 FT-IR、SEM 和 TEM 对 RLMP、RLMP-1 和 RLMP-2 的结构特征进行分析。采用甲基化分析和 NMR 阐明 RLMP-1 的糖链结构。体外降血糖活性分析表明，RLMP 可提高葡萄糖消耗和糖原合成，并增强 IR-HepG2 细胞中丙酮酸激酶和己糖激酶的活性。此外，RLMP 还显著增加了抗氧化酶（如 CAT、SOD 和 GSH-Px）的活性，降低了 ROS 和 MDA 的水平。Western blot 分析证实，RLMP 通过激活 PI3K/Akt/GLUT-4 信号通路，增强葡萄糖和脂质代谢，降低氧化应激，从而发挥其降血糖作用。这些发现表明，RLMP 是开发新型抗氧化剂或降血糖药物的有前途的候选物。
