酮洛芬前体药物经皮吸收的选择性及代谢机理研究

Transdermal drug delivery system is an increasing active field of drug preparation study. Skin is the mainly barrier of transdermal penetration, and is rich in enzyme activity, so the study on skin metabolism of drug is very important to the study on percutaneous absorption. The stratum corneum, the rate-limiting barrier to percutaneous absorption, is made up of keratin and ceramides, which could potentially provide a chiral environment. Differential binding of enantiomers to keratin or interactions with ceramide may give rise to differences in the permeation profiles of enantiomers, and have influence on the clinical effect of enantiomer. Therefore the transdermal delivery of enantiomers of chiral species is an increasing active and promising field. .Ketoprofen, a nonsteroidal anti-inflammatory drug, is used as model drug for synthesizing a series of ester prodrugs in this paper. The characteristic of percutaneous absorption and mechanism of skin esterase metabolism were discussed. Ketoprofen and its ester prodrug were separated by HPLC using α-acid glycoprotrin column. Excised skin was prepared by surgical excision and enzyme digestion. Side-by-side diffusion cells were used for in vitro permeation studies using whole thickness skin, stripped skin and dermis as permeation membrane, so the active site of skin metabolism and the stereoselective characteristic were determined. HaCaT cell line derived from human abdominal keratinocyte was used to study the dynamic characteristic of prodrug metabolism, and the type of carboxylesterase in HaCaT cell was also clarified. The in situ perfused pig ear or rabbit ear model for percutaneous absorption were established, methyl salicylate and ketoprofen isopropyl ester were used for validating these model, and the difference between biotransformation rates were compared..The determination of ketoprofen and its prodrug in cell culture fluid, skin homogenate and receiver solutin of permeation was not affected by impurity such as protein. The HPLC method was accurate, and meet for analysis. Ketoprofen ester prodrug can be hydrolyzed in infant and adult epidermis homogenate, New Zealand rabbit epidermis homogenate, weanling pig epidermis homogenate, and SD rat epidermis homogenate. The hydrolysis reaction has stereoselectivity at the beginning except SD rat homogenate, the main product is R-ketoprofen. Ketoprofen esters can be metabolized to ketoprofen in in situ skin during percutaneous penetration process in HuangShan monkey skin, BABL/C nude mouse skin and SD rat skin. Skin esterase metabolism mainly develops in the epidermis. In the HaCaT cell culture system, the metabolism of ketoprofen ester also has stereoselectivity, especially ketoprofen isopropyl ester, their product are mainly R-ketoprofen. HaCaT cell can express human carboxylesterase-2. Two in situ models of percutaneous absorption were established based on the ear vein perfusion. One model is about rabbit ear, the influences of protein concentration, flow rate of buffer and temperature were determined, methyl salicylate was applied to this model. Another model is about pig ear, its biological activity can be kept during seven hours, methyl salicylate and ketoprofen isopropyl ester were metabolized to salicy acid and ketoprofen during percutaneous penetration, Azone has enhancive effect on permeation and metabolism of methyl salicylate..The main metabolite of ketoprofen ester in HaCaT cell homogenate and human skin homogenate is R-ketoprofen, especially ketoprofen isopropyl ester, this may be due to the selectivity of carboxylesterase. R-ketoprofen does not inhibit the activity of cyclooxygenase, but has better analgesic effect, may become a novel drug in the treatment of toothache. So HaCaT cell is a better carrier for synthesizing chiral drug by biological method, and is a novel thought for separating enantiomers. Along with the study on expression and purifying of carboxylesteras in HaCaT cell, a novel biological method for synthesizing chiral drug will be acquired, and the mechanism about setereoselective hydrolysis in

以酮洛芬衍生物KPD-02为模型药物，探讨手性前体经皮吸收的立体选择性差异及皮肤酯酶的生物转化作用。在KPD-02手性拆分及纯对映体制备的基础上，考察经皮吸收过程中的手性特征及代谢机理，建立在体经皮吸收（幼猪耳部皮肤）有渗透/代谢模型，为药物透皮吸收制恋难兄坪涂⑻峁┓椒ㄖ傅己图际踅杓