De Meester I, Belyaev A, Lambeir A M, De Meyer G R, Van Osselaer N, Haemers A, Scharpé S
Laboratory of Medical Biochemistry, University of Antwerp, Wilrijk, Belgium.
Biochem Pharmacol. 1997 Jul 1;54(1):173-9. doi: 10.1016/s0006-2952(97)00149-4.
Dipeptidyl peptidase IV (DPP IV, EC 3.4.14.5), also known as CD26, is a membrane-bound serine protease that cleaves off aminoterminal dipeptides from peptides with a penultimate proline (or, at a much slower rate, a penultimate alanine). Recently, we synthesized and characterized a number of dipeptide-derived diphenylphosphonates. Out of the resulting series of slow-binding irreversible inhibitors of DPP IV, diphenyl 1-(S)-prolylpyrrolidine-2(R,S)-phosphonate hydrochloride (Pro-Pro-diphenylphosphonate or Prodipine) was selected for further study. We investigated the in vivo applicability of Prodipine. Male rabbits weighing 3-4 kg received a single intravenous injection with 10 mg Prodipine or saline. After 1 hr, plasma DPP IV activity had decreased to less than 20% of the preinjection value and remained unchanged during a 24-hr observation period. In a next step, we aimed to study (i) the dose dependency and (ii) the duration of the effect after a single intravenous dose of Prodipine. A profound and long-lasting inhibition of plasma DPP IV activity was observed in the treated animals (1, 5 or 10 mg). It took 5 to 8 days to reach half of the pretreatment DPP IV activity and generally more than 20 days for a complete recovery. Systemic treatment with Prodipine not only led to inhibition of plasma DPP IV activity but also decreased tissue DPP IV activity in circulating mononuclear cells, kidney cortex, thymus, spleen, lung, and liver. No differences in activities of the related peptidases aminopeptidase P (APP, EC 3.4.11.9), prolyl oligopeptidase (PO, EC 3.4.21.26), or aminopeptidase M (mAAP, EC 3.4.11.2) were detected between Prodipine-treated and control rabbits. The in vivo applicability of this chemically stable, irreversible inhibitor of DPP IV opens new possibilities, not only to further unravel the biological functions of this intriguing ectopeptidase, but also to explore this enzyme as a new target in various fields of pharmacological research.
二肽基肽酶IV（DPP IV，EC 3.4.14.5），也称为CD26，是一种膜结合丝氨酸蛋白酶，可从倒数第二个脯氨酸（或以慢得多的速率，倒数第二个丙氨酸）的肽中切割掉氨基末端二肽。最近，我们合成并表征了许多二肽衍生的二苯基膦酸酯。在所得的一系列DPP IV慢结合不可逆抑制剂中，选择1-（S）-脯氨酰吡咯烷-2（R，S）-二苯基膦酸盐酸盐（Pro-Pro-二苯基膦酸酯或Prodipine）进行进一步研究。我们研究了Prodipine的体内适用性。体重3-4千克的雄性兔子接受10毫克Prodipine或生理盐水的单次静脉注射。1小时后，血浆DPP IV活性降至注射前值的20%以下，并在24小时观察期内保持不变。下一步，我们旨在研究（i）单次静脉注射Prodipine后的剂量依赖性和（ii）作用持续时间。在接受治疗的动物（1、5或10毫克）中观察到血浆DPP IV活性受到深刻而持久的抑制。达到预处理DPP IV活性的一半需要5至8天，完全恢复通常需要超过20天。用Prodipine进行全身治疗不仅导致血浆DPP IV活性受到抑制，还降低了循环单核细胞、肾皮质、胸腺、脾脏、肺和肝脏中的组织DPP IV活性。在接受Prodipine治疗的兔子和对照兔子之间，未检测到相关肽酶氨基肽酶P（APP，EC 3.4.11.9）、脯氨酰寡肽酶（PO，EC 3.4.21.26）或氨基肽酶M（mAAP，EC 3.4.11.2）的活性差异。这种化学稳定的DPP IV不可逆抑制剂的体内适用性开辟了新的可能性，不仅可以进一步揭示这种有趣的外肽酶的生物学功能，还可以将该酶作为药理学研究各个领域的新靶点进行探索。
