ABSTRACT
BACKGROUND:The carriers made from biodegradable and biocompatible polymeric materials represent an exciting approach to increase the bioavailability and stability of oral y administered insulin by the chemical reaction or physical encapsulation of insulin. OBJECTIVE:To mainly review the research progress of the material types, preparation methods, physicochemical characteristics, in vitro release kinetics, and bioavailability of polymeric materials adopted as oral insulin carriers. METHODS:The first author searched PubMed, Elsevier and CNKI databases for articles (2002-01/2013-02) concerning the polymeric materials and oral insulin carriers with the key words of“polymeric biomaterials, oral insulin, carrier”in English and in Chinese. RESULTS AND CONCLUSION:Currently, there are mainly two kinds of polymeric biomaterials used for oral insulin delivery systems, that is, natural polymeric biomaterials (such as chitosan and alginates) and synthetic polymeric biomaterials. The most commonly used synthetic polymeric materials for the preparation of these vehicles are polyesters, polyacrylates and their copolymers, which are wel known for their good biodegradability, biocompatibility, and physiological properties. Although researchers have tried to develop promptly oral insulin formulation using various technologies, the reports about clinical application or commercial success have not been seen because of several questions such as polymer material as a carrier, the lower bioavailability of insulin, the quality standards and stability of the formulation. Hence, future studies wil focus on the development of a new type of polymer-based material as carriers by choosing the new materials or modifying physical and chemical characteristics of existing polymers, to avoid gastrointestinal destruction of the insulin and increase bioavailability of insulin in the body, so as to obtain the good control ed release rate and effect.
ABSTRACT
[Objective] To discuss the effect of Kangfuning Mixture on castrated rats’ ?-endorphin(?-EP), exposing its mechanism in preventing and treating peri-climateric period syndrome. [Method] Establish castrated rats model, test rats’ changes of hypothalamus, hypoplysis and ?-EP with radioimmuno method and fluorospectrophotometry. [Result] Kangfuning Mixture can increase the content of ?-EP in plasma, hypothalamus and hypoplysis of rats in peri-climateric period, also the level of serum E2. [Conclusion] Through regulating nerve-incretory disorder, Kangfuning Mixture can improve peptide nerve function and maintain relatively stable internal environment of organ.