ABSTRACT
The abnormal lipids metabolism is a critical pathological feature of coronary heart disease (CHD). Additional supplemental intake of polyunsaturated fatty acid (PUFA) has long been considered to be an effective strategy for preventing CHD, but more and more clinical trials have denied this view. Still, it is ambiguity for the specific mechanism of PUFA in CHD. The experimental programs are compliant with ethical principles for animal use and have been approved by the Animal Experiment Ethics Committee of Jinan University. In the present study, we established an animal model by intake of omega-6 PUFA combined acute myocardial ischemia to explore the mechanism of CHD. Intragastric administration of linoleic acid (LA) for 14 days, intraperitoneal injection of isoprenaline (ISO) was applied to induce acute myocardial ischemia for the animal model establishment. The animal ultrasound imaging system was used to detect cardiac function in vivo after ISO injection for 24 h. Serum and heart tissue samples were collected for the myocardial enzyme, phospholipidomics analysis and molecular biological detection. Compared to the LA group, the cardiac function showed that the left ventricular ejection fraction (EF%) and the left ventricular shortening fraction (FS%) decreased, aspaetate aminotransferase (AST), creatine kinase isoenzyme (CK-MB), and lactate dehydrogenase (LDH) increased in the LA + ISO mice. Compared to the ISO group, the phospholipidomics analysis showed that the PUFAs significantly were raised in the LA + ISO myocardium, and the content of oxidized phosphatidylethanolamine (ox-PE) changed most remarkable. Compared with the ISO group, the molecular biology detection showed that glutathione (GSH) and nicotinamide adenine dinucleotide phosphate (NADPH) were depleted, the end-products of ox-PE were increased, and the level of arachidonic acid 12/15-lipoxygenase (ALOX15) protein expression increased obviously. We suggest that ALOX15 mediated phospholipid peroxidation might be the critical mechanism of LA increased the susceptibility of myocardial ischemia injury. This study provides an experimental basis for whether PUFA could be used as an alternative treatment strategy for CHD prevention and provides a new intervention target for the early prevention strategy of CHD.
ABSTRACT
Post-marketing evaluation of traditional Chinese medicine(TCM) is an important research stage in the life cycle of a drug, and the add-on-design is a common method for its post-marketing evaluation. This article introduces the basic concept of add-on-design, and points out that it is suitable for use based on the principles of medical ethics when the standard treatment should not be interrupted. The post-marketing evaluation of TCM should be carried out based on human experience and in compliance with regulations and ethics. The clinical values of TCM, such as the therapeutic effect for disease, improvement of disease symptoms, improvement in quality of life, as well as the synergism and toxicity attenuation of combined use of TCM and chemical drugs, should be fully reflected through the clinical trials designed with add-on-design. The key points of add-on-design are accurate clinical positioning, scientific estimation of sample size, and rigorous standard treatment. Standard treatment should be a recognized one, consistent and stable; appropriate and recognized efficacy indicators and targeted safety indicators should be selected; the design and operation of clinical research scheme should meet the requirements of randomization and blind method, with special emphasis on the production of qualified placebo. The add-on-design has the advantages that the rights and interests of the subjects are adequately protected. Besides, the research conclusions are easily put into clinical application. But there are also many difficulties, such as the influence of confounding bias, the "ceiling" effect of clinical efficacy, and the difficulty of interpretation of adverse events. Therefore, a rigorous research quality assu-rance system should be established, and the quality control of evaluation consistency of researchers should be emphasized to ensure strict quality control in the research process.