Summary: | 博士 === 高雄醫學大學 === 藥學研究所 === 96 === The seed of Cuscuta chinensis Lam. (Convolvulaceae), a common traditional Chinese herb, has been used for centuries in the practice of medicated diet and dietetic therapy. Previous studies have indicated that C. chinensis possesses some pharmacological actvities. However, the antioxidant activity and hepatoprotective effect of C. chinensis have not yet been reported. The antioxidant activities were determined by several in vitro antioxidant activity assays, and also quantitated and characterized the flavonols in the different extracts and organic fractions from the seeds of C. chinensis. Moreover, as oxidative stress promotes the development of acetaminophen (APAP)-induced hepatotoxicity, I also evaluated and compared in vivo the hepatoprotective effects and antioxidant activities of the water (CH) and ethanol extract (CE) of C. chinensis on APAP-induced hepatotoxicity in rats. The results showed that the antioxidant activities of CE was more potent than CH, and a direct correlation between the flavonol content and the antioxidant activities from the extracts and fractions of C. chinensis was observed. In addition, the C. chinensis ethanol extract displayed a significant hepatoprotective effect by reducing levels of liver function index, increasing levels of antioxidant enzymes, and reducing lipid peroxidation. In contrast, CH did not exhibit any hepatoprotective effects that are seen in the CE. Furthermore, in recent years, the more efficient use of herbal medicine has helped to decrease the amount of herb material used and aid in coping with the resource restriction of traditional Chinese herb. Novel pharmaceutical technologies for drug preparation such as nanoparticle formulations are invented to increase drug efficacy, its bioavailability, and decrease the amount of material use. Due to the poor water solubility of CE, its absorption upon oral administration could be limited. Nanonization is one of the methods for drug size reduction which can improve the bioavailability of CE, as confirmed by these results. Indeed, an oral dose of C. chinensis nanoparticles that is 5 times as less as the CE was observed to exhibit similar hepatoprotective and antioxidant effects. In conclusion, the study report here for the first time novel therapeutic effects for C. chinensis, including its antioxidant and hepatoprotective activities. The study has also demonstrated for the first time that the use of C. chinensis nanoparticles can help decrease the dosage of CE while achieving the same level of effects. The nanonization of the drug which enhances the drug efficacy would translate to decreased cost and waste of herbal material. Accordingly, the study suggests modernization and potential international development in the application of herbal medicine.
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