Radioprotective Effect In Radiation-induced Lung Injury And Inhibition Effect In Lung Cancer Of Polydatin

BackgroundRadiation-induced lung injury(RILI)is the most common serious complication in radiotherapy of thoracic tumors.It often occurs in acute radiation such as nuclear emergencies and chest radiotherapy of lung cancer,breast cancer,esophageal cancer and other tumors.The main clinical manifestations of radiation-induced lung injury is inflammatory infiltration of alveolar stroma,progressive dyspnea,deterioration of lung function and eventually leading to respiratory failure.Radiation-induced lung injury is one of the most common and most important complications of radiotherapy in patients with thoracic tumor.It has seriously affected the prognosis and quality of life of thoracic tumor radiotherapy patients.There is no consensus on the mechanism of radiation-induced lung injury.The main view is that the main pathogenesis of radiation-induced a variety of cells and their associated cytokine imbalance caused by excessive proliferation of fibroblasts and extracellular interstitial deposition,related to the same time,radiation induced by a large number of oxygen free radicals Oxidative stress injury also plays an important role in its occurrence,the development process throughout the lung tissue injury,inflammation and repair of various stages.The current lack of clinical prevention and treatment of radiation-induced lung injury effects of drugs,limiting the chest tumor patients with radiation therapy effect.Therefore,in the clinical treatment of radiation-induced lung injury,the urgent need to find a significant effect,small side effects,high safety of new drugs.Polydatin(PD),which is mainly extracted from the stem roots and roots of the Polygonaceae plant Polygonum cuspidatum,is one of the natural active ingredients.Polydatin has a wide range of sources,has a clear molecular structure,easy to synthetic,low prices,has been widely used in the daily health care of the human body.Polydatin is a powerful free radical scavenger,at the same time with anti-inflammatory,anti-oxidation,protection of vascular endothelial cells.In addition,polydatin has a variety of human tumor cells have a killing effect.The drug's lethal dose of more than 1000mg/kg,far greater than its therapeutic dose,toxic side effects,showing a better biosafety.Combined with the characteristics of polydatin,we believe that the drug in clinical radioactive lung injury in the existence of a huge potential value.Contents1,Protective effect of polydatin on radiation-induced lung injury:(1)The effect of polydatin on the pathological and lung coefficient changes of lung tissue induced by ionizing radiation;(2)The effect of polydatin on lung tissue histopathological changes induced by ionizing radiation;(3)Effect of polydatin on epithelial mesenchymal transition induced by ionizing radiation;(4)Effect of polydatin on pulmonary epithelial cell injury induced by ionizing radiation.2,Mechanism of protective effect of polydatin on radiation-induced lung injury:(1)The effect of polydatin on TGF-?1/Smad3/Snail pathway;(2)The effect of polydatin on the secretion of TGF-?1 and ET-1;(3)The effect of polydatin on the balance of Th1/Th2 cells;(4)The effect of polydatin on the secretion of inflammatory cytokines related to radiation-induced lung injury;(5)The effect of polydatin on the level of hydroxytru toxin,SOD and MDA;(6)The effect of polydatin on the expression of Sirt protein family.3,Tumor growth inhibition effect of polydatin:(1)The establishment of mouse lung tumor model;(2)The effect of polydatin on the survival rate of tumor-bearing mice;(3)The effect of polydatin on the lung tissue of tumor-bearing mice;(4)The effect of polydatin on the pathological changes of lung tissue in tumor-bearing mice;(5)The killing effect of polydatin on lung cancer cells.Method1,The establishment of mouse radiation-induced lung injury model: use the self-designed C57BL/6 mouse mold fixed,so that the mouse limbs fully extended,exposed mice nose and mouth on the outside of the mold,the use of paper clips fixed mouse limbs and tail.With the bricks to block the mouse outside the chest area,use the does of 15 Gy of a single expose,the dose rate is 1Gy/min.2,The protective effect of polydatin on radiation-induced lung injury:(1)Animal grouping and treatment: 120 C57BL/6 female mice were divided into four groups randomly,namely,the control group,irradiation group,polydatin treatment group,WR2721 treatment group,conduct corresponding treatment respectively.(2)Comparison of the changes of pulmonary tissue and the change of lung coefficient in each group after ionizing radiation;(3)Changes of pathological tissue: H&E Staining,Masson's Trichrome staining,immunohistochemical staining and TUNEL staining were conducted of the lung tissue of each groups respectively;(4)Lung tissue epithelial mesenchymal transition comparison: Western Blot and immunofluorescence staining method to detect lung tissue markers ?-SMA,Vimentin and E-cadherin;(5)Detection of hydroxyproline expression in lung tissue;(6)Cell treatment: human bronchial epithelial cells BEAS-2B was selected,detect the protective effect of polydatin for ionizing radiation-induced cells injury;(7)Cell proliferation test: CCK-8,clonal formation rate.3,Mechanism of protective effect of polydatin on radiation-induced lung injury:(1)Investigate the effect of polydatin on TGF-?1/Smad3/Snail pathway by immunohistochemical staining;(2)Investigate the effect of polydatin on TGF-?1,IL-13,PGE2,TNF-? and other cytokines;(3)Detect the removal ability of polydatin from hydroxyl radicals by ESR method;(4)Detect the effect of polydatin on the expression of SOD and MDA in lung tissue;(5)Cell treatment: Select human bronchial epithelial cell BEAS-2B to detect whether polydatin had an effect on the expression of Sirt family protein.4,Lung cancer cells inhibition effect of polydatin:(1)The establishment of mouse lung tumor model: use DMEM medium resuspend the mouse Lewis lung cancer cell LLC,prepared 2 × 106 concentration of cell suspension.Animals were anesthetized with 10% chloral hydrate and left on the operating table and fixed.After disinfection,at the 10 mm right side of the thoracic xiphoid,cut the skin and stripped the muscle of the anterior chest wall,exposed mouse thoracic wall and intercostal space,visible activities of the lower right lobe.In the case of naked eye,through the right mouse first or second intercostal space vertical needle,the needle depth is 5mm,injection of cell suspension 25?L.Layer sutured mouse muscle and skin,re-disinfection,and make it rejuvenated wake up;(2)To observe the growth of pulmonary tissue in the polydatin and the control group by general observation.(3)The histopathological changes of lung tumor tissue in the treatment group and the control group were compared by pathology.(4)To compare the growth of pulmonary tissue from the polydatin and the control group by living imaging.(5)At the cytological level,the effect of polydatin on normal lung tissue cells and lung tumor cells was compared.Results1,Protection effect of polydatin on radiation-induced lung injury:(1)The comparison with the results of lung tissue and lung volume show that polydatin can significantly reduce the degree of pulmonary edema caused by ionizing radiation,thus controlling the increasing lung coefficient caused by ionizing radiation;(2)Compared with H&E staining,Masson staining and TUNEL staining,polydatin showed significant inhibitory effect on lung tissue at the early and late stages of radiation-induced lung injury,and could significantly inhibit the apoptosis induced by ionizing radiation;(3)Hydroxyproline content tests showed that polydatin had a significant inhibitory effect on ionized radiation-induced increase in hydroxyproline;(4)Immunofluorescence and Western Blot showed that polydatin had a significant inhibitory effect on EMT induced by ionizing radiation;(5)Cytological results show that polydatin has a significant inhibitory effect on ionizing radiation-induced apoptosis.2,Mechanism of protective effect of polydatin on radiation-induced lung injury:(1)The results of immunohistochemistry showed that polydatin had a significant inhibitory effect on TGF-?1/Smad3/Snail pathway;(2)Polydatin significantly inhibited the levels of TGF-?1 and ET-1;(3)The uptake of cytokines secreted by Th1 and Th2 cells in the polydatin treatment group was significantly inhibited,suggesting that polydatin was sensitive to radiation-induced expression of TGF-?1 and ET-1 Th1/Th2 immunoregulation has a certain regulatory effect;(4)Polydatin can delay the decline of PGE2 process,and significantly inhibit the process of TNF-? increase,suggesting that polydatin has a strong anti-inflammatory effect;(5)Polydatin has a strong antioxidant capacity,to a great extent to remove hydroxyl free radicals,inhibition of lung tissue SOD reduction,reduce lung tissue's MDA level;(6)Polydatin can activate the expression of Sirt protein,especially for Sirt3,Sirt6 agonism is more significant.3,Lung cancer cells inhibition effect of polydatin:(1)The mouse lung tumor model was successfully established;(2)Polydatin can significantly prolong the survival time of tumor-bearing mice;(3)Polydatin can significantly retard the growth of lung tumors;(4)Polydatin has a certain killing effect on tumor cells.Conclusion1,Polydatin can significantly reduce the pathological changes of lung tissue,reduce pulmonary edema,inhibition of epithelial cell stromal transformation process,reduce the degree of radiation-induced lung injury.At the cytological aspect,polydatin showed the same protective effect.2,Polydatin may inhibit the ?1/Smad3/Snail pathway,reduce the release of fibrosis factors and inflammatory cytokines,regulate the balance of Th1/Th2 immune cells,stimulate the expression of Sirt protein in vivo,anti-inflammatory and anti-oxidation play a protective effect on radiation-induced lung injury.3,In this study,we established a model of mouse lung tumor,and through this model,it was proved that polydatin can significantly prolong the survival time of tumor-bearing mice,delay the growth of lung tumors,and have some anti-tumor cells effect.4,In summary,polydatin has the advantages of high efficiency and low toxicity,low price,anti-inflammatory and anti-oxidation,regulating the immune response of the body,and also can extend the survival time of lung tumor-bearing mice,delay the growth and development of tumor cells,has great potential value in clinical lung cancer radiotherapy radioactive lung injury.