Factors affecting the intestinal absorption of orally-administered physiologically active proteins in rat

影响大鼠口服生理活性蛋白肠道吸收的因素

• 批准号: 08456065
• 负责人: KAKINUMA Atsushi
• 金额: $ 4.67万
• 依托单位: Nagoya University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08456065/
• 关键词: Intestinal absorption of proteins; Intestinal absorption of proteases; Orally-available anti-inflammatory protease; Serratia protease; Development of orally-available high mole-cular weight pharmacenticals; lncrease of intestinal absorption of protei

Our observation that Serratia protease (SP,MW 50,600) orally-administered to scalded rats dramatically repressed the enhancement of fibrinolysis and blood vessel permeability both induced by the scalding, strongly suggested its intestinal absorption. To investigate this possibility, we established a highly-sensitive EIA and a protease assay for determining SP concentration in rat plasma, and succeeded in demonstrating that a portion of orally-administered SP was absorbed from the intestinal tract in an enzymatically active form. This was the first observation clearly indicating that orally-administered physiologically active proteins can be transferred from the intestine to the blood stream without losing its original activity to exert eventually a systemic function in the body.Since, we have been trying to identify any physiological or nutritional factors that may control the degree of the intestinal absorption of SP in rat. In the preious experiment, we investigated the effect of age … More and feeding on the absorption (A.Kakinuma : in Abstracts of Research Project, Grant-in-Aid for Scientific Research (B) (1995, Project No.06454083).Results of the present investigation are summarized as follows.1.We analyzed the time-course of the change of SP concentration in portal vein plasma, tail vein plasma and in mesenteric lymph after oral administration to know that SP is first absorbed from intestine by way of lymph and then transferred to blood.2.The coexistence of such substances as proteins and lipids in orally-administered SP solutions influenced the degree and the pattern of SP absorption. Especially, the presence of 60% (v/v) corn oil increased the amount of SP absorbed more than 10 times by incorporating SP into the emulsion formed by oil and water and enabling SP to escape from the denaturation by gastric acid and subsequent degradation by proteinases.3.Surfactin, an anionic peptidelipid surfactant produced by B.subtilis and isolated by us (Biochem.Biophys.Res.Commun.31,488 (1968)) gave an effect different from that of corn oil described in 2. Although SP administered together with surfactin was completely inactivated in stomach (pH3), some SP-derived molecule, presunably inactivated SP,was absorbed, transferred to blood and detected in plasma by our EIA.Its maximum plasma concentration, increased 1.4-1.5 times, was realized at 1h after administration, in contrast to 2h after adminstration in the absence of surfactin. Surfactin seems to influence the molecular mechanism of absorption of SP in addition to the stability of SP in stomach and intestine. Less

我们观察到，烫伤大鼠口服沙雷氏菌蛋白水解酶(SP，Mw 50,600)可显著抑制烫伤引起的纤溶和血管通透性的增强，强烈提示其在肠道中的吸收。为了探讨这种可能性，我们建立了一种高灵敏度的EIA和一种测定大鼠血浆中SP浓度的蛋白酶测定法，并成功地证明了口服SP的一部分是以具有酶活性的形式从肠道吸收的。这是第一次清楚地表明，口服生理活性蛋白可以从肠道转移到血流中，而不会失去其原有的活性，最终在体内发挥全身功能。自那以来，我们一直试图确定可能控制大鼠肠道对SP吸收程度的任何生理或营养因素。在先前的实验中，我们研究了AGE-…的作用。研究结果如下：1.分析了口服给药后门静脉血浆、尾静脉血浆和肠系膜淋巴中SP浓度变化的时程，了解到SP首先通过淋巴途径从肠道吸收，然后转移到血液中。2.口服SP溶液中蛋白质和脂类物质的共存影响SP吸收的程度和方式。特别是，60%(v/v)玉米油的存在使SP被油和水形成的乳状液中的SP吸收了10倍以上，使SP得以逃脱胃酸变性和随后的蛋白酶降解。3.由枯草杆菌产生的一种阴离子多肽表面活性物质，由我们(BioChem.BiPhys.Res.Commun.31,488,1968)产生，其效果与文献2中所述的玉米油不同。虽然SP与表面蛋白一起在胃中完全灭活(PH3)，但SP衍生的一些未被激活的SP分子被吸收了，其血药浓度在给药后1h达到最大值，是给药后2小时的1.4-1.5倍。表面活性物质除了影响SP在胃和肠道中的稳定性外，似乎还影响其吸收的分子机制。较少

项目成果

Norihiko Moriya: "Intestinal Absorption of Serrapeptase(TSP) in Rats" Biotechnol.Appl.Biochem.20. 101-108 (1994)

Norihiko Moriya：“大鼠沙雷肽酶（TSP）的肠道吸收”Biotechnol.Appl.Biochem.20。