Milovic V
2nd Department of Medicine, Johann Wolfgang Goethe University, Theodor Stern Kai 7, D-60590 Frankfurt, Germany.
Eur J Gastroenterol Hepatol. 2001 Sep;13(9):1021-5. doi: 10.1097/00042737-200109000-00004.
Polyamines arrive in the gut lumen mainly with food. Shortly after a meal, the majority of luminal polyamines disappear from the duodenal and jejunal lumen, by a mechanism of passive diffusion. The majority of luminal polyamines are degraded in the gut before reaching systemic circulation. Hence, there is broad evidence that luminal polyamines are indeed absorbed, distributed throughout the body, and utilized for cellular growth in remote organs and tissues. In addition, luminal polyamines are crucially involved in normal, adaptive and neoplastic growth of the gut per se, and are taken up by normal and neoplastic epithelial cells of the gut mucosa by a tightly regulated and presumably active transport process. Uptake of polyamines into intestinal and colonic epithelial cells is the highest during cell proliferation, and is stimulated by mitogens and peptide growth factors. Understanding the mechanisms of polyamine uptake in neoplastic cells of the gut, as well as the "biodistribution/bioavailability" of luminal polyamines in man, may provide clinically relevant information that can be used in inhibiting cancer cell growth by deprivation of intracellular polyamine pools.
多胺主要随食物进入肠道腔。进食后不久，大部分肠腔多胺通过被动扩散机制从十二指肠和空肠腔中消失。大部分肠腔多胺在到达体循环之前就在肠道中被降解。因此，有广泛的证据表明，肠腔多胺确实被吸收，分布到全身，并用于远处器官和组织的细胞生长。此外，肠腔多胺对肠道本身的正常、适应性和肿瘤性生长至关重要，并通过严格调控且可能是主动运输的过程被肠道黏膜的正常和肿瘤上皮细胞摄取。在细胞增殖期间，多胺进入小肠和结肠上皮细胞的摄取量最高，且受有丝分裂原和肽生长因子的刺激。了解肠道肿瘤细胞中多胺摄取的机制，以及人体中肠腔多胺的“生物分布/生物利用度”，可能会提供临床上相关的信息，可用于通过剥夺细胞内多胺池来抑制癌细胞生长。
