| BackgroundFibrosis could lead to disorganization and hypofunction, even failure of organ. Pulmonary interstitial fibrosis (PF) is a series of diffused pulmonary interstitial disease caused by many factors, and is a heterogeneous disease as well as the common end of many pulmonary diseases.The pathogenesis was complex,and research shew the occurrence and development of pulmonary interstitial fibrosis were closely correlated with high expression of TGF-β1.Transforming growth factor-β1 known as the key cell factor in the formation and progression of pulmonary interstitial fibrosis,could regulate differentiation hyperplasia and excretion of extracellular membrane (ECM) as a multifunctional and super effective cell factor, and increase accumulation and inhibit degradation of ECM. TGF-β1 plays an important role in transcription and translation on the processes of collagens,and induce the production of pre-collagen mRNA,advance formation and deposition of collagen protein. it is the most direct cell factor in pulmonary fibrosis. It's obvious that inhibiting the expression of TGF-β1 is helpful to delay the process of pulmonary fibrosis, but the effect is still unsatisfactory by conventional anti-fibrosis drugs to inhibit the expression of TGF-β1。RNA interference is a new molecular biological technology, and it can import the corresponding sense RNA and antisense RNA which are called double strand RNA (dsRNA)to induce specific target mRNA with homological sequences to degrade in the recipient cell, and then to prevent the translation process of protein.The effect is similar to gene knock-out, but the disappearance of genetic expression is temporary,also called "gene silencing"ObjectiveTo construct the specific small interfereing RNA(siRNA) Duplication-deficiency adenovirus vector that can block the rat TGF-β1 gene according to the mRNA of rat TGF-(31,To investigate the inhibitory effect of TGF-β1 transgenic expression on bleomycin-induced pulmonary fibrosis in mice.Materials and methods60 male Sprague-Dawley (SD) rats were treated with bleomycin by 5mg per kg weight via trachea on day 0 in the normal saline group, therapeutic group (AdCMV TGF-β1) and sham recombinant adenoviruses(AdCMVNull),Adenoviral vector with murine TGF-β1SiRNA (AdCMVTGF-β1)10×109plague forming unit (pfu) was administrated via nostril instillation 24h after bleomycin treatment in the therapeutic group, Mice treat Fluorescence Quantitative PCR and the TGF-β1 level in the blood serum was quantitatively determined by EnzymeLinked immunosorbent Assay.ed with a same volume of normal saline (NS) and a same dosage of sham recombinant adenoviruses (AdCMV Null) served as controls.The animals were killed on day 7,14,28,The right lung was stained with either hematoxylin-eosin,and the expression of TGF-β1 in the lung was detected by immunohistochemical technique;the TGF-β1mRNA expression in lung was detected by Real-time. ResultThe alveolitis and fibrosis of the treatment group were less than that in normal saline group and sham recombinant adenoviruses group in HE sections.The immunohistochemistry expression of TGF-β1 in treatment group was significantly lower than the normal saline group and sham recombinant adenoviruses group (P<0.05);the TGF-β1 mRNA expression was significantly lower than other normal saline group and sham recombinant adenoviruses group (P<0.05),the TGF-β1 expression in blood serum was no statistical significance in all the groups(P>0.05).ConclusionThe RNA interference mediated by Adenovirus vector can inhibit the expression of TGF-beta1 in lungs of mice with pulmonary fibrosis;reduce the alveolitis and fibrosis of pulmonary in rats with pulmonary fibrosis.but the expression of TGF-beta1 in serum were not impacted.
|
PDF Full Text Request