【摘要】：細(xì)胞穿膜肽是一種能夠自主并攜帶多種貨物分子進(jìn)入細(xì)胞的短肽，具有低生物毒性、高運(yùn)載效率、高生物相容性、能夠突破血腦屏障等多種優(yōu)勢(shì)，是近20年來(lái)迅速發(fā)展的一種新型藥物載體。 然而，細(xì)胞穿膜肽的研究和應(yīng)用中也面臨著一些問(wèn)題。第一，細(xì)胞穿膜肽的穿膜機(jī)制目前尚沒(méi)有得到完全的認(rèn)識(shí)。第二，在體應(yīng)用細(xì)胞穿膜肽時(shí)往往選擇更加穩(wěn)定的D型穿膜肽，但是D型穿膜肽的毒性更大，同時(shí)手性變化對(duì)于穿膜肽性質(zhì)的影響也存在爭(zhēng)論。第三，也是令研究者最關(guān)注的一點(diǎn)，在應(yīng)用細(xì)胞穿膜肽轉(zhuǎn)運(yùn)貨物分子進(jìn)入細(xì)胞時(shí)，特別是在在體水平給藥時(shí)，貨物分子會(huì)被困在囊泡(胞吞泡)中無(wú)法行使功能甚至被降解失活，從而降低了轉(zhuǎn)運(yùn)藥物分子的實(shí)際效力。目前，尚無(wú)在體水平實(shí)現(xiàn)細(xì)胞穿膜肽于胞質(zhì)中直接投遞的報(bào)道。在在體水平實(shí)現(xiàn)無(wú)囊泡束縛的、直接的胞內(nèi)投遞已成為當(dāng)前細(xì)胞穿膜肽發(fā)展應(yīng)用的一個(gè)重要熱點(diǎn)。 針對(duì)上述問(wèn)題，本文構(gòu)建了一類混合不同比例D/L型精氨酸的新型寡聚精氨酸類穿膜肽，系統(tǒng)分析了該系列穿膜肽在不同孵育環(huán)境下的穿膜性質(zhì)，總結(jié)了D型氨基酸對(duì)于富含精氨酸類穿膜肽的穿膜性質(zhì)的影響規(guī)律�；谶@種規(guī)律，本文從這一系列穿膜肽中篩選得到了一種同時(shí)具有低生物毒性和高穿膜效率的寡聚精氨酸穿膜肽；基于該穿膜肽，本文首次實(shí)現(xiàn)了在體給藥后的細(xì)胞穿膜肽無(wú)囊泡束縛的胞內(nèi)直接投遞。進(jìn)一步的，依賴于這一系列具有不同穿膜性質(zhì)的穿膜肽，本文對(duì)這類新型寡聚精氨酸細(xì)胞穿膜肽的穿膜機(jī)理進(jìn)行了系統(tǒng)研究和闡述。本文具體研究?jī)?nèi)容如下： (1)為了系統(tǒng)研究氨基酸手性變化對(duì)于細(xì)胞穿膜肽的影響，本文構(gòu)建了一類基于混合D/L型精氨酸的新型寡聚精氨酸穿膜肽系列，并對(duì)其進(jìn)行表征。 (2)分析了不同條件下，該系列穿膜肽的亞細(xì)胞分布、穿膜效率、生物毒性（包括細(xì)胞毒性和系統(tǒng)毒性）和生物穩(wěn)定性（包括酶穩(wěn)定性和血清穩(wěn)定性）�？偨Y(jié)了D型精氨酸對(duì)于這類穿膜肽的穿膜性質(zhì)變化的影響規(guī)律。依據(jù)于這種規(guī)律性，在所設(shè)計(jì)的細(xì)胞穿膜肽系列中篩選獲得了一種同時(shí)具有高穿膜效率、低生物毒性，以及能夠分別在細(xì)胞水平和活體水平實(shí)現(xiàn)胞質(zhì)內(nèi)直接投遞的細(xì)胞穿膜肽(rR)3R2。 (3)通過(guò)對(duì)細(xì)胞穿膜肽穿膜機(jī)制的系統(tǒng)研究，證明富含精氨酸類的細(xì)胞穿膜肽具有2種獨(dú)立的穿膜機(jī)制：胞吞作用穿膜機(jī)制及特殊的直接穿膜機(jī)制。其中，直接穿膜機(jī)制是一種依賴于細(xì)胞能量和細(xì)胞膜電位的從細(xì)胞膜邊緣開(kāi)始的快速穿膜過(guò)程�；谠摍C(jī)制，，穿膜肽能夠從細(xì)胞膜邊緣開(kāi)始，直接進(jìn)行胞質(zhì)內(nèi)投遞，并在細(xì)胞內(nèi)彌散均勻分布。
[Abstract]:Cellular transmembrane peptide is a kind of short peptide that can enter cells independently and carry many kinds of cargo molecules. It has many advantages, such as low biotoxicity, high transport efficiency, high biocompatibility, and the ability to break through the blood-brain barrier and so on. It is a new drug carrier developed rapidly in the past 20 years. However, there are some problems in the research and application of cell-penetrating peptides. First, the transmembrane mechanism of cellular peptides has not been fully understood. Secondly, the more stable D-type transmembrane peptides are often used in vivo, but the toxicity of D-type transmembrane peptides is more serious, and the influence of chiral changes on the properties of transmembrane peptides is also controversial. Third, which is also of great concern to researchers, is the use of cell-penetrating peptides to transport cargo molecules into cells, especially at the level of drug delivery in vivo. Cargo molecules are trapped in vesicles (vesicles) and can not function or even deactivate, thus reducing the actual effectiveness of drug delivery molecules. At present, there are no reports of cell transmembrane peptide delivered directly in the cytoplasm at the level of body. Direct intracellular delivery without vesicle binding has become an important focus in the development and application of cellular membrane peptides. In order to solve the above problems, a new type of poly-arginine transmembrane peptides mixed with different ratios of D / L type arginine was constructed, and the transmembrane properties of the series of transmembrane peptides under different incubation conditions were systematically analyzed. The effects of D-amino acids on the transmembrane properties of arginine-rich transmembrane peptides were summarized. Based on this rule, we have obtained an oligomeric arginine transmembrane peptide with low biotoxicity and high membrane penetration efficiency from the series of transmembrane peptides. In this paper, we first realized the direct delivery of cellular membrane penetrating peptide without vesicle binding after in vivo administration. Furthermore, depending on this series of transmembrane peptides with different transmembrane properties, the mechanism of the transmembrane peptides of this new type of oligoarginine cells has been systematically studied and explained in this paper. The main contents of this paper are as follows: (1) in order to systematically study the effect of amino acid chiral changes on cellular transmembrane peptides, a new type of oligomeric arginine transmembrane peptides based on mixed D / L arginine was constructed. (2) the subcellular distribution, transmembrane efficiency, biotoxicity (including cytotoxicity and systemic toxicity) and biological stability (including enzyme stability and serum stability) of this series of transmembrane peptides were analyzed under different conditions. The effect of D type arginine on the transmembrane properties of this kind of transmembrane peptide was summarized. Based on this regularity, a novel cell membrane penetrating peptide series with high membrane penetration efficiency and low biotoxicity was obtained. And the cellular transmembrane peptide (rR) 3R2, which can be delivered directly into the cytoplasm at the cell level and in vivo, respectively. (3) the mechanism of cell transmembrane peptide transmembrane is studied systematically. The results showed that the membrane penetrating peptides rich in arginine had two independent transmembrane mechanisms: cytosolic transmembrane mechanism and special direct transmembrane mechanism. The mechanism of direct transmembrane penetration is a rapid transmembrane process which depends on cell energy and cell membrane potential from the edge of cell membrane. Based on this mechanism, transmembrane peptides can be delivered directly into the cytoplasm from the edge of the cell membrane and distribute evenly in the cells.
【學(xué)位授予單位】：華中科技大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2012
【分類號(hào)】：R318.04

【共引文獻(xiàn)】

相關(guān)期刊論文 前10條

1 李劍峰;蔣晨;;腦膠質(zhì)瘤靶向藥物遞送系統(tǒng)[J];國(guó)際藥學(xué)研究雜志;2013年05期

2 謝向陽(yáng);林雯;李e

本文編號(hào)：2272115