本文選題：殼寡糖 + 氧化應(yīng)激��； 參考：《中國海洋大學(xué)》2005年博士論文

【摘要】：機體在細胞有氧代謝過程中不斷的產(chǎn)生自由基。在正常生理條件下,自由基不斷的被清除。體內(nèi)抗氧化防御體系包括酶解和非酶解兩種機制。當(dāng)異源性藥物、毒物在體內(nèi)的代謝過程中產(chǎn)生活性中間代謝產(chǎn)物,導(dǎo)致活性氧的過量產(chǎn)生,或者機體的防御體系受到損傷時,就會導(dǎo)致活性氧化應(yīng)激狀態(tài)。大量的研究資料表明氧化應(yīng)激與很多疾病的發(fā)生密切相關(guān)。因此抗氧化劑及其作用機制的研究在醫(yī)學(xué)上具有重要意義。還原型谷胱甘肽是機體最重要的非酶抗氧化劑,維持谷胱甘肽含量的穩(wěn)態(tài)在很多病理過程中具有重要意義。L-半胱氨酸是提高GSH含量的主要途徑,但是L-半胱氨酸在一定濃度時具有毒性而且容易被氧化,L-半胱氨酸前體化合物是有效的提高促進GSH合成,治療氧化應(yīng)激有關(guān)的疾病的有效手段。噻唑啉糖衍生物是L-半胱氨酸與糖類分子中的羰基縮合形成的環(huán)狀化合物,它在體內(nèi)能夠通過非酶的水解反應(yīng)釋放出L-半胱氨酸,促進GSH的從頭合成,提高GSH的含量,保護機體,具有廣泛的生物學(xué)、醫(yī)學(xué)功能。 殼寡糖是通過甲殼素脫乙酰得到的,它具有生物相容性、可降解性、無免疫原性、無毒和易吸收等特點,在藥物學(xué),食品等領(lǐng)域具有非常廣泛的應(yīng)用。近年來殼寡糖抗氧化功能的研究備受關(guān)住,但是在這方面的研究還不多,對其抗氧化機制尚未充分研究,而且關(guān)于殼寡糖降解產(chǎn)生的單糖—氨基葡萄糖的抗氧化功能,目前國內(nèi)外尚未見報導(dǎo)。本實驗利用L-半胱氨酸和氨基葡萄糖,N-乙酰氨基葡萄糖制備了兩種新的噻唑烷酸糖衍生物(GlcNH_2Cys,GlcNAcCys),對其熔點、比旋光、IR波譜和1H-NMR波譜進行了測定,結(jié)合兩種已見報道合成的噻唑烷酸糖衍生物(GluCys,GalCys)的結(jié)構(gòu),比較并得出其結(jié)構(gòu)為噻唑啉羧酸結(jié)構(gòu)。 本實驗通過體外、體內(nèi)實驗研究殼寡糖,氨基葡萄糖及其衍生物的抗氧化、肝保護功能。利用體外試驗方法研究了氨基葡萄糖及其衍生物的自由基清除能力,還原力,金屬絡(luò)合能力以及對羥自由基誘導(dǎo)的生物大分子如脂類、脫氧核糖和蛋白質(zhì)的氧化性損傷的保護作用。利用四氯
[Abstract]:The body produces free radicals in the process of cell aerobic metabolism. Under normal physiological conditions, free radicals are constantly eliminated. Antioxidant defense system in vivo includes two mechanisms: enzymatic hydrolysis and non-enzymatic hydrolysis. When xenogeneic drugs and poisons produce active intermediate metabolites during metabolism in vivo, which results in excessive production of reactive oxygen species, or when the body's defense system is damaged, it will lead to active oxidative stress. A large number of studies have shown that oxidative stress is closely related to the occurrence of many diseases. Therefore, the study of antioxidant and its mechanism is of great significance in medicine. Reduced glutathione is the most important non-enzymatic antioxidant in the body. Maintaining the steady-state of glutathione content is of great significance in many pathological processes. L- cysteine is the main way to increase the content of GSH. However, L- cysteine is toxic at a certain concentration and can be easily oxidized. L- cysteine precursor compounds are an effective way to promote GSH synthesis and to treat oxidative stress-related diseases. Thiazolinose derivative is a cyclic compound formed by condensation of L-cysteine with carbonyl group in carboxylic molecules. It can release L-cysteine through non-enzymatic hydrolysis in vivo, promote the ab initio synthesis of GSH and increase the content of GSH. Protection of the body, with a wide range of biological and medical functions. Chitosan oligosaccharide is obtained by deacetylation of chitin. It has the characteristics of biocompatibility, biodegradability, non-immunogenicity, non-toxicity and easy absorption. It has been widely used in pharmaceutical, food and other fields. In recent years, the research on the antioxidation function of chitosan oligosaccharides is very close, but there are few researches in this field. The mechanism of antioxidation of chitosan oligosaccharides has not been fully studied, and the antioxidation function of monosaccharide-glucosamine produced by the degradation of chitosan oligosaccharides has not been fully studied. At present, no reports have been reported at home and abroad. In this paper, two new thiazolidate sugar derivatives, GlcNH2Cys2Cys-GlcNAcCysA, were prepared from L-cysteine and glucosamine N-acetylglucosamine. Their melting point, specific optical rotation IR spectra and 1H-NMR spectra were determined. The structure of two kinds of thiazolidate sugar derivative GluCys-GalCysA was compared and the structure of thiazoline carboxylic acid was obtained. The antioxidation and liver protection of chitosan, glucosamine and its derivatives were studied in vitro and in vivo. The free radical scavenging ability, reductive power, metal complexing ability of glucosamine and its derivatives were studied in vitro, and the biological macromolecules such as lipids induced by hydroxyl radical were studied. Protective effects of deoxyribose and protein on oxidative damage. Utilization of tetrachlo
【學(xué)位授予單位】：中國海洋大學(xué)
【學(xué)位級別】：博士
【學(xué)位授予年份】：2005
【分類號】：R341

【參考文獻】

相關(guān)期刊論文 前6條

1 蔣?,薛培華,陳士明,李文俊;殼聚糖對超氧陰離子自由基和亞油酸脂類自由基的抑制作用[J];科學(xué)通報;2002年03期

2 金鳴，蔡亞欣，李金榮，，趙輝;鄰二氮菲－Fe~（2＋）氧化法檢測H_2O_2／Fe~（2＋）產(chǎn)生的羥自由基[J];生物化學(xué)與生物物理進展;1996年06期

3 欽傳光,周軍,趙文,黃開勛,徐輝碧;泥鰍多糖清除活性氧和保護DNA鏈的作用[J];生物化學(xué)與生物物理學(xué)報;2001年02期

4 徐桂云,崔慶榮;甲殼低聚糖清除羥自由基性能的研究[J];山東輕工業(yè)學(xué)院學(xué)報(自然科學(xué)版);2001年02期

5 張延良;孫昌俊;陳再成;李祥安;王汝聰;;噻唑烷酸糖衍生物的合成及其抗腫瘤活性[J];醫(yī)藥工業(yè);1988年04期

6 孫瑞華,湯旦林;臨床試驗數(shù)據(jù)管理與統(tǒng)計分析(1)[J];中國新藥雜志;2001年07期

本文編號：1938820