隔离,血管 perfused 鼠肠的葡萄糖吸收:一个显著的细胞对象贡献增强SGLT1抑制
Cecilie Bæch-Laursen1,2, Rune Kuhre Ehrenreich1,3,4, Ida Marie Modvig1,3
1Department of Biomedical Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
Acta physiologica (Oxford, England)
|April 5, 2025
概括
肠道葡萄糖的吸收涉及通过SGLT1/GLUT2和被动细胞路径的活性运输. 阻断这些输送器揭示了剩余的葡萄糖吸收,这表明显著的细胞通路,特别是在近端肠道.
科学领域:
- 胃肠病学 胃肠病学
- 生理学 生理学 生理学
- 分子生物学分子生物学
背景情况:
- 肠道葡萄糖吸收主要通过SGLT1 (顶端) 和GLUT2 (下侧) 运输体进行介导.
- 在体内研究表明,葡萄糖吸收率超过了输送能力,这意味着其他途径.
- 这项研究使用了体外模型来研究葡萄糖吸收机制.
研究的目的:
- 为了研究葡萄糖吸收途径在一个孤立的透小肠小肠模型.
- 为了区分跨细胞和半细胞葡萄糖运输.
- 评估SGLT1和GLUT2在葡萄糖吸收中的作用.
主要方法:
- 隔离的血管 perfused 鼠小肠模型.
- 对14C-d-葡萄糖吸收的量化.
- 使用佛洛里津和佛洛瑞丁抑制SGLT1和GLUT2.
- 使用14C-d-曼尼托尔对细胞运输的评估.
主要成果:
- 葡萄糖的吸收通过SGLT1/GLUT2介导的细胞间传输和细胞通路发生.
- 阻断SGLT1可减少60%的吸收;阻断GLUT2可减少80%的吸收.
- 在SGLT1和GLUT2联合阻断后,葡萄糖吸收的~30%持续存在,当SGLT1被阻断时,曼尼托尔吸收增加.
结论:
- 肠道葡萄糖吸收包括活跃的跨细胞和被动的细胞机制,特别是在近端小肠.
- 准细胞运输起着重要作用,并可能由SGLT1活动调节.
- 这些发现对于理解与葡萄糖吸收相关的激素分泌至关重要.
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