本文選題：Galectin-3 + 急性心肌梗死��； 參考：《吉林大學(xué)》2013年博士論文

【摘要】：心衰是各種心血管疾病的終末階段,具有較高的死亡率,如何減慢或延緩心室重塑的進(jìn)展是心衰治療領(lǐng)域中的研究熱點(diǎn)。同時(shí),人們一直在尋找新的生物學(xué)標(biāo)志物,該標(biāo)志物不僅要能夠反應(yīng)心衰本身的發(fā)生、進(jìn)展,還要能更早的識(shí)別和診斷心衰患者,具有疾病監(jiān)測(cè)及指導(dǎo)治療的價(jià)值,這將有利于改善患者預(yù)后,降低死亡率,從而使患者更多獲益。 心肌重塑是心衰發(fā)生與發(fā)展重要的病理基礎(chǔ),是心功能由代償向失代償演變的關(guān)鍵步驟,BNP、NT-proBNP[2]能很好的反映心室重構(gòu)的情況,因而被應(yīng)用于診斷心衰、評(píng)估心衰治療效果及判斷心衰預(yù)后的指標(biāo)。當(dāng)BNP或NT-proBNP不高時(shí)，有助于排除左心收縮功能不全的診斷。但由于BNP和NT-proBNP水平受多種因素影響,如心動(dòng)過(guò)速,右心負(fù)荷過(guò)重,心肌缺血,低氧血癥,’腎功能不全,高齡,肝硬化,感染等,使其診斷心衰的價(jià)值有所下降。此外,BNP和NT-proBNP與心力衰竭疾病本身的進(jìn)展無(wú)關(guān),監(jiān)測(cè)NT-proBNP并不能改善患者的預(yù)后[2]。因此,亟待我們尋找特異性的生化指標(biāo)或與其配合使用來(lái)指導(dǎo)患者的治療。 目前,半乳凝素-3(Galectin-3)被認(rèn)為是心肌細(xì)胞纖維化的新型生物標(biāo)志物[3]。Galectin-3是由巨噬細(xì)胞激活分泌的,可以反映炎癥和纖維化激活,具有誘導(dǎo)成纖維細(xì)胞增殖、Ⅰ型膠原沉積的作用。有研究表明[4],給予健康SD大鼠連續(xù)低劑量心包注射Galectin-3,4周后大鼠出現(xiàn)左心功能不全,進(jìn)一步研究發(fā)現(xiàn)Galectin-3影響膠原蛋白的增生,表現(xiàn)為Ⅰ型膠原、Ⅲ型膠原增加的比例不協(xié)調(diào),Ⅰ型膠原的增多率是Ⅲ型膠原增多率的3倍,而Ⅰ型膠原、Ⅲ型膠原的表達(dá)增加且增加比率不協(xié)調(diào)是導(dǎo)致左心功能不全發(fā)生的原因之一。另外,Galectin-3可通過(guò)促進(jìn)心臟巨噬細(xì)胞浸潤(rùn)、刺激纖維母細(xì)胞活化進(jìn)而參與心肌纖維化的形成,而巨噬細(xì)胞和纖維母細(xì)胞在心肌纖維化過(guò)程中具有重要作用。同樣,急性心肌梗死(acute myocardial infarction, AMI)發(fā)生后,大量心肌細(xì)胞壞死,炎癥因子大量釋放,誘導(dǎo)巨噬細(xì)胞遷移、纖維母細(xì)胞活化、成纖維細(xì)胞增生,由此我們推斷,急性心肌梗死發(fā)生后,可能存在Galectin-3的過(guò)度表達(dá),導(dǎo)致不適當(dāng)?shù)男募±w維化,進(jìn)而引發(fā)心功能不全的出現(xiàn)。但目前對(duì)于Galectin-3在急性心梗發(fā)病過(guò)程中的作用研究較少,且受那些因素影響也尚不清楚。 此外,Galectin-3還可以通過(guò)基質(zhì)金屬蛋白酶(matrix metalloproteinases, MMPs)和金屬蛋白酶組織抑制劑(tissue inhibitors of metalloproteinases,TIMPs)抑制細(xì)胞外基質(zhì)的降解,從而導(dǎo)致心肌成纖維細(xì)胞增生,膠原蛋白合成增加。有研究表明[5]，MMPs/TIMPs平衡是維持心肌成纖維細(xì)胞膠原合成與降解代謝平衡的關(guān)鍵。如果MMPs的活性過(guò)度增加或者M(jìn)MPs/TIMPs(比例)嚴(yán)重失調(diào),將導(dǎo)致心室重構(gòu)、心肌纖維化的發(fā)生[6]。心力衰竭時(shí),心肌MMPs/TIMPs的平衡狀態(tài)被破壞,不僅使MMPs持續(xù)激活,還可引起細(xì)胞外基質(zhì)(Extracellular matrixc, ECM)的蛋白水解和相應(yīng)的心肌重構(gòu)。有實(shí)驗(yàn)證明,除MMPs/TIMPs比例失調(diào)會(huì)導(dǎo)致心肌重構(gòu)外,MMPs還可通過(guò)其他途徑導(dǎo)致心肌重構(gòu)的發(fā)生。如心肌細(xì)胞受損后,ECM退化,導(dǎo)致心肌排列紊亂,收縮功能異常,為進(jìn)一步的細(xì)胞外基質(zhì)重構(gòu)奠定了基礎(chǔ)。而且在ECM退化的刺激下,機(jī)體通過(guò)增加ECM的合成以期維持平衡,但這種增生往往是過(guò)度的,組成成分也是不恰當(dāng)?shù)�。膠原和纖連蛋白等ECM組分在數(shù)量上的增長(zhǎng)使心肌僵硬,收縮無(wú)力,舒張障礙。此外,MMPs通過(guò)趨化作用使纖維細(xì)胞進(jìn)入其作用后的區(qū)域,介導(dǎo)TNF-α、TGF-β等細(xì)胞因子活化,刺激心肌纖維細(xì)胞大量增生,啟動(dòng)膠原及纖黏連蛋白基因的轉(zhuǎn)錄。上述細(xì)胞因子可促進(jìn)膠原合成、破壞心肌細(xì)胞,這將導(dǎo)致MMPs表達(dá)增加,由此形成惡性循環(huán),加速心室重構(gòu)。因此,MMPs及MMPs/TIMPs平衡對(duì)心室重塑的發(fā)展有著重要的影響。Galectin-3既能影響MMPs的活性,也能引起TIMPs功能改變,那么Galectin-3對(duì)MMPs/TIMPs是如何影響的,這也是本研究關(guān)注的另一焦點(diǎn)。 另外,還有實(shí)驗(yàn)研究發(fā)現(xiàn),在心力衰竭治療中聯(lián)合應(yīng)用血管緊張素轉(zhuǎn)換酶抑制劑和MMPs抑制劑可減輕左室擴(kuò)張而不引起心肌硬化,說(shuō)明有效控制MMPs的功能,是防治心肌重塑的手段之一。Hayashidani等[7]發(fā)現(xiàn)氟伐他汀可抑制左室膠原酶、MMP-2、MMP-13的表達(dá),減少心臟膠原容積分?jǐn)?shù),減輕心梗后大鼠心肌肥厚和間質(zhì)纖維化,說(shuō)明他汀可能會(huì)引起MMPs/TIMPs比率的變化,進(jìn)而影響心肌纖維化。這也是本研究要探討的另外一個(gè)重要問(wèn)題。 本研究中,首先選取106例急性心�；颊邽檠芯繉�(duì)象,常規(guī)接受PCI治療。根據(jù)患者的癥狀、體征及NT-proBNP、EF值等結(jié)果,診斷其心功能分級(jí),然后分析心功能與Galectin-3的關(guān)系。其次,通過(guò)結(jié)扎雌性大鼠冠狀動(dòng)脈左前降支(LAD)建立心梗后心衰動(dòng)物模型,4w后灌胃大鼠阿托伐他汀,設(shè)立假手術(shù)組,模型對(duì)照組及藥物干預(yù)組。再連續(xù)給藥4w后,進(jìn)行如下檢測(cè)：ELISA法檢測(cè)血清中BNP、Galectin-3水平；HE染色和Masson染色觀察心肌病理形態(tài)學(xué)；Western-blot檢測(cè)MMP-2和TIMP-2的表達(dá)；明膠酶譜法檢測(cè)MMP-2的活性；實(shí)時(shí)定量PCR檢測(cè)膠原蛋白Ⅰ、膠原蛋白Ⅲ、MMP-2和TIMP-2的mRNA表達(dá)。最后,體外分離培養(yǎng)大鼠心肌成纖維細(xì)胞,以AngⅡ誘導(dǎo)心肌成纖維細(xì)胞增殖模型,并給予外源性阿托伐他汀進(jìn)行干預(yù),進(jìn)行如下檢測(cè)：MTT法檢測(cè)細(xì)胞增殖；ELISA法檢測(cè)血清中羥脯氨酸、PⅠCP和PⅢNP含量；實(shí)時(shí)定量PCR檢測(cè)膠原蛋白Ⅰ、膠原蛋白Ⅲ、MMP-2和TIMP-2的mRNA表達(dá)。 本研究結(jié)果顯示：①隨著患者心功能的不斷惡化,Galectin-3呈逐漸升高的趨勢(shì),應(yīng)用阿托伐他汀干預(yù)4周后,Galectin-3水平下降。②成功建立心梗后心衰的大鼠模型。與假手術(shù)組比較,模型對(duì)照組大鼠血請(qǐng)BNP水平增高；心肌細(xì)胞排列紊亂,大量纖維組織增生；與模型對(duì)照組比較,阿托伐他汀干預(yù)組大鼠血清BNP、Galectin-3水平下降；心肌細(xì)胞排列較整齊,纖維增生程度減弱；MMP-2活性下降；膠原蛋白Ⅰ、膠原蛋白Ⅲ、MMP-2和TIMP-2的mRNA表達(dá)有所下降。進(jìn)一步研究發(fā)現(xiàn),經(jīng)阿托伐他汀干預(yù)后,MMP-2/TIMP-2比率升高,心肌纖維化程度降低。③體外成功培養(yǎng)大鼠心肌成纖維細(xì)胞,并建立AngⅡ誘導(dǎo)的大鼠心肌成纖維細(xì)胞增殖模型。與模型組相比,AngⅡ組心肌成纖維細(xì)胞分泌脯氨酸、PⅠCP和PⅢNP含量增加,膠原蛋白Ⅰ、膠原蛋白Ⅲ、MMP-2和TIMP-2的mRNA表達(dá)增多,且經(jīng)阿托伐他汀干預(yù)后,MMP-2/TIMP-2比率升高。 綜上,Galectin-3可能預(yù)測(cè)急性心梗后心衰的發(fā)生,應(yīng)用阿托伐他汀后,Galectin-3水平下降,心肌纖維化程度降低,說(shuō)明Galectin-3可用于或與其他指標(biāo)聯(lián)合用于評(píng)價(jià)心功能：初步探討了阿托伐他汀抑制心肌纖維化的機(jī)制可能為：①抑制Galectin-3表達(dá),導(dǎo)致MMP-2、TIMP-2的功能及表達(dá)量降低,減輕心肌纖維化。②抑制心肌成纖維細(xì)胞合成膠原蛋白Ⅰ和膠原蛋白Ⅲ的合成,減輕心肌纖維化。③應(yīng)用阿托伐他汀后，，MMP-2/TIMP-2的表達(dá)比率上調(diào),使膠原的降解大于合成,進(jìn)而減輕心肌纖維化。
[Abstract]:Heart failure is the final stage of all kinds of cardiovascular diseases, with high mortality. How to slow down or delay the progress of ventricular remodeling is a hot spot in the field of heart failure. At the same time, people have been looking for new biological markers, which not only reflect the occurrence and progress of heart failure itself, but also be able to identify and diagnose earlier. Patients with heart failure have the value of monitoring and guiding treatment. This will help improve the prognosis and reduce the mortality rate, so that patients can benefit more.
Myocardial remodeling is an important pathological basis for the occurrence and development of heart failure. It is the key step of cardiac function from compensatory to decompensation. BNP, NT-proBNP[2] can reflect the condition of ventricular remodeling, so it is used to diagnose heart failure, evaluate the effect of heart failure and determine the prognosis of heart failure. When BNP or NT-proBNP is not high, it is helpful to exclude BNP and NT-proBNP levels are affected by many factors, such as tachycardia, excessive right heart load, myocardial ischemia, hypoxemia, kidney dysfunction, age, cirrhosis, infection and so on, and the value of the diagnosis of heart failure has been reduced. In addition, BNP and NT-proBNP are not related to the progress of heart failure itself, Monitoring NT-proBNP can not improve the prognosis of [2].. Therefore, we need to find specific biochemical indicators or cooperate with them to guide the treatment of patients.
At present, galactoin -3 (Galectin-3) is considered to be a new biomarker of myocardial fibrosis, [3].Galectin-3 is activated by macrophages, which can reflect the activation of inflammation and fibrosis, which can induce fibroblast proliferation and type I collagen deposition. A study showed that [4] was given to healthy SD rats for a continuous low dose of pericardium. After Galectin-3,4 weeks, left ventricular dysfunction was found in rats. Further study found that Galectin-3 affects collagen proliferation, which is type I collagen, the proportion of type III collagen is not coordinated, and the increase rate of type I collagen is 3 times that of type III collagen increase, while type I collagen and type III collagen increase and increase the ratio is incongruous One of the causes of left ventricular dysfunction is that Galectin-3 can promote the formation of myocardial fibrosis by stimulating macrophage infiltration and stimulating fibroblast activation, and macrophages and fibroblasts play an important role in the process of myocardial fibrosis. The same, acute myocardial infarction (acute myocardial infarction). After the occurrence of AMI) a large number of myocardial cells were necrotic and inflammatory factors were released, inducing macrophage migration, fibroblast activation, fibroblast proliferation. Therefore, we infer that after acute myocardial infarction, there may be overexpression of Galectin-3, causing discomfort of myocardial fibrosis and leading to the appearance of cardiac dysfunction. There is less study on the role of Galectin-3 in the pathogenesis of acute myocardial infarction, and the influence of those factors is not yet clear.
In addition, Galectin-3 can also inhibit the degradation of extracellular matrix through the matrix metalloproteinases (matrix metalloproteinases, MMPs) and metalloproteinase tissue inhibitors (tissue inhibitors of metalloproteinases, TIMPs), resulting in the proliferation of myocardial fibroblasts and the increase of collagen synthesis. There is a study showing [5], MMPs/TIMPs equilibrium. It is the key to maintain the metabolic balance of collagen synthesis and degradation in cardiac fibroblasts. If excessive increase in MMPs activity or severe imbalance of MMPs/TIMPs (proportion), it will lead to ventricular remodeling, and when [6]. heart failure occurs in myocardial fibrosis, the balance of MMPs/TIMPs in the myocardium is broken, which not only causes the MMPs to continue to activate, but also causes the extracellular matrix. The protein hydrolysis of Extracellular matrixc (ECM) and the corresponding myocardial remodeling. It has been proved that MMPs can also lead to myocardial remodeling in other ways except for the imbalance of MMPs/TIMPs, such as the degeneration of the myocardium, the degeneration of ECM, the disorder of the myocardium, the abnormal contractile function, and the further extracellular matrix. Mass remodeling lays the foundation. And under the stimulation of ECM degradation, the body maintains a balance by increasing the synthesis of ECM, but the proliferation is often excessive and the components are not appropriate. The increase in ECM components, such as collagen and fibronectin, makes myocardial stiffness, contraction weakness, and diastolic dysfunction. In addition, MMPs is made by chemotaxis. Fibrous cells enter the area after its action, mediate the activation of TNF- a, TGF- beta and other cytokines, stimulate the proliferation of myocardial fibroblasts and activate the transcription of collagen and fibronectin gene. These cytokines can promote collagen synthesis and destroy cardiac myocytes, which will lead to an increase in the MMPs table, thus forming a vicious cycle and accelerating ventricular remodeling. Therefore, MMPs and MMPs/TIMPs balance have an important influence on the development of ventricular remodeling..Galectin-3 can affect both the activity of MMPs and the change of TIMPs function, then how Galectin-3 affects MMPs/TIMPs, which is another focus of this study.
In addition, experimental studies have found that combined use of angiotensin converting enzyme inhibitors and MMPs inhibitors in the treatment of heart failure can reduce left ventricular dilatation without causing myocardial sclerosis, indicating that effective control of MMPs function is one of the means to prevent myocardial remodeling, such as.Hayashidani, [7] found that fluvastatin can inhibit left ventricular collagenase, MMP-2, M. The expression of MP-13 reduces cardiac collagen volume fraction, reduces myocardial hypertrophy and interstitial fibrosis in rats after myocardial infarction, indicating that statins may cause changes in the ratio of MMPs/TIMPs to myocardial fibrosis, which is also an important issue to be discussed in this study.
In this study, first of all, 106 patients with acute myocardial infarction were selected as the subjects and received PCI treatment routinely. According to the symptoms, signs and NT-proBNP, EF values, the classification of cardiac function was diagnosed and the relationship between cardiac function and Galectin-3 was analyzed. Secondly, by ligating the left anterior descending branch of the coronary artery (LAD) of the female rats, the heart failure animals were established. Model, 4W after gastric perfusion of atorvastatin, set up a sham operation group, model control group and drug intervention group. After continuous administration of 4W, the following tests were carried out: ELISA method was used to detect the serum BNP, Galectin-3 level, HE staining and Masson staining to observe the myocardial pathomorphology; Western-blot detected the expression of MMP-2 and TIMP-2; gelatin zymogram detection MMP-2 activity; real-time quantitative PCR was used to detect the mRNA expression of collagen I, collagen III, MMP-2 and TIMP-2. Finally, the rat myocardial fibroblasts were isolated and cultured in vitro, and the proliferation model of myocardial fibroblasts was induced by Ang II, and the exogenous atorvastatin was given the following detection: MTT method was used to detect cell proliferation; ELISA Methods the contents of hydroxyproline, P I CP and P III NP in serum were detected. The mRNA expression of collagen I, collagen III, MMP-2 and TIMP-2 was detected by real-time quantitative PCR.
The results of this study showed that: (1) with the continuous deterioration of cardiac function, Galectin-3 showed a tendency to increase gradually. After 4 weeks of atorvastatin intervention, the level of Galectin-3 decreased. (2) the rat model of heart failure after myocardial infarction was successfully established. Compared with the sham operation group, the level of BNP in the model control group was higher; the myocardial cells were arranged in disorder, Compared with the model control group, the serum BNP, Galectin-3 level of the rats in the Atorvastatin intervention group decreased, the myocardial cells were arranged neatly, the degree of fibrous proliferation was weakened, the activity of MMP-2 decreased, and collagen I, collagen III, MMP-2 and TIMP-2 decreased. Further studies found atropine. The MMP-2/TIMP-2 ratio increased and the degree of myocardial fibrosis decreased. (3) the rat myocardial fibroblasts were successfully cultured in vitro, and the rat fibroblast proliferation model induced by Ang II was established. Compared with the model group, the content of proline, P I CP and P III NP in Ang II group was increased, collagen I, collagen eggs The expression of mRNA in white III, MMP-2 and TIMP-2 increased, and the ratio of MMP-2/TIMP-2 increased after atorvastatin intervention.
To sum up, Galectin-3 may predict the occurrence of heart failure after acute myocardial infarction. After the use of atorvastatin, the level of Galectin-3 decreased and the degree of myocardial fibrosis decreased, indicating that Galectin-3 can be used to evaluate cardiac function combined with other indicators: the mechanism of atorvastatin to inhibit myocardial fibrosis may be: (1) inhibition of Galectin- The expression of 3 led to the decrease of function and expression of MMP-2, TIMP-2 and the reduction of myocardial fibrosis. 2. Inhibit the synthesis of collagen I and collagen III of myocardial fibroblasts and reduce myocardial fibrosis. (3) after atorvastatin, the expression ratio of MMP-2/TIMP-2 was up-regulated, the degradation of collagen was greater than that of synthesis, and then myocardial fibrosis was alleviated.
【學(xué)位授予單位】：吉林大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2013
【分類號(hào)】：R541.61

【共引文獻(xiàn)】

相關(guān)期刊論文 前3條

1 尤丹瑜;萬(wàn)建新;;氟伐他汀對(duì)系膜細(xì)胞增殖及Ⅳ型膠原表達(dá)的影響[J];中國(guó)醫(yī)藥導(dǎo)刊;2009年04期

2 王成玉;薛超;黎偉;廖蘊(yùn)華;;連續(xù)性非臥床腹膜透析1個(gè)月后血脂血糖變化分析[J];廣西醫(yī)學(xué);2011年09期

3 張冬;孫雪峰;;終末期腎病患者心血管疾病的診斷與防治[J];中國(guó)循證心血管醫(yī)學(xué)雜志;2012年01期

本文編號(hào)：1926597