Studies On Novel Drugs Of Anti-myocardial Ischemia/reperfusion Injury

Cardiovascular and cerebrovascular diseases called "the first killer" are the major disease which seriously hazard human's health and cause a high mortality in the world. Ischemic heart disease is one of the leading causes. Shortening ischemia time of the tissue and recovering blood flow early are the most effective measures to prevent ischemia injury. But these therapies can lead to myocardial ischemia/reperfusion injury (MI/R). The clinical drugs for treatment of ischemic heart disease can be mainly divided into three types: nitrates,βblockers and calcium antagonists. There are also some reports about the combination therapy to treat ischemic heart disease. However, these therapies have different side effects or can not be used for a long term due to drug resistance. Therefore, developing a new drug to treat myocardial ischemia /reperfusion injury with high efficiency, low toxicity would be of great clinical significance.MI/R produces a large number of reactive oxygen species which can not be cleared in time. These reactive oxygen species can lead to lipid peroxidation, resulting in apoptosis, organ or tissue damage, which inactivates NO rapidly. NO converts into "injury factors" such as nitric acyl anion (NO-), and peroxynitrite (ONOO-) in the body. This finally leads to the resistance to nitrate. Aims1. The aim of this research is to design and synthesize new molecules which can both remove ROS and release NO at the same time. To study the pharmacodynamics of anti-myocardial ischemia / reperfusion injury with the target molecule, in order to obtain structures have better myocardial protective effect than the existing NO donor drug ISMN.2. Preparaed of a new type of modified reverse polarity column packing which is an effective analytical tool for investigating the pharmacokinetic of the target products.Methods and Results1. Designed and synthesized three target compounds:AcDI-302: was prepared by DCC, DMAP condensation, 79% total yield.AcGI-405: was prepared by chloride and alcohol in alkaline conditions, 64% yield.AcGI-406: Using Mitsunobu method to converte hydroxyl of ISMN to amino yield: 50.3%, then reacted with chloride under alkaline conditions to prepare AcGI-406, yield 39%. 2. Designed and synthesized a modified reverse polarity column packing, then evaluated its performance and studied its application, and obtained the expected results. (1) Preparation of modified polar RP column: High-purity silica gel reacted with octadecyl dimethyl chlorosilane to prepare C18 bonded phase, then reacted with polar groups to obtain the modified polar stationary phase.(2) Performance evaluation of modified polar column: The results of Engelhardt test and Dolan test showed that the polarity modified column we prepared had high selectivity, high sensitivity and excellent column efficiency. Successive injections of the same samples 3,000 times, the process of retention time, peak shape did not change, which indicated the column packing was stable and good reproducibility.(3) Application of modified polar column: The polarity modified column was applied to separate a variety of mixtures. The results showed that: it could separate (i) The mixture of 4-amino benzoicacid, sorbic acid and benzoic acid; (ii) The mixture of category 5 representative alkaloid; (iii) Cephalosporins; (iv) Pseudoephedrine and acetaminophen; (v) Aniline and its derivatives;(vi) target molecules, AcDI302, AcGI-405, AcGI-406 . Results showed an excellent peak shape under high-water mobile phase and in wide pH conditions.(4) The polarity modified column was applied to study preliminary pharmacokinetic of AcDI302. Under the conditions of strong interference of endogenous substances, the high selective separation efficiency was obtained, which provided a powerful tool for us to deeply study pharmacokinetic of these target molecules.3. Results of AcDI302 treatment of MI/R in rats: Male Sprague-Dawley rats were subjected to 30 minutes of myocardial ischemia and 3 hours of reperfusion to prepare reperfusion model, collecting ECG,±dP/dtmax, LVDP and other hemodynamic parameters, CK, LDH, MDA, NO levels in serum and myocardial infarct size, etc. Statistical analysis showed that AcDI-302 can significantly reduce the ischemia-reperfusion caused by myocardial injury and improve ischemic cardiac function. The effect of AcDI-302 was stronger than the positive control drug ISMN.