Mechanism and Current Situation of Decorporation Agents for Radionuclide Contamination in vivo
Radioactive contamination can occur during nuclear accidents,loss of radioactive sources and the use of radiation for photography,disinfection and detection.When the human body is accidentally contaminated by radionuclides,radionuclides can cause harm to the human body through inhalation,ingestion,direct transdermal absorption and contaminated wounds into body tissues and organs.In the treatment of radionuclide contamination in vivo,the main way is decorporation therapy,which mainly uses specific decorporation agents to selectively bind radionuclides to form stable non-toxic complexes,thereby preventing their deposition in the body,accelerating excretion,and reducing the total accumulation of radionuclides in human tissues.At present,internal radionuclide decorporation agents promote the release of radionuclides from the body mainly by stopping the entry of radionuclides into the body,ion exchange,chelation,and binding of exportants to carriers.But recent studies have found that lysosomal exocytosis,the natural clearing function of activated cells,also has a significant exportation effect.In this paper,we first introduced and analyzed the mechanism and research status of radionuclide decorporation agents that have been used in clinical practice,such as the blocking effect of potassium iodide,the ion exchange effect of Prussian blue,the chelation effect of DTPA,and the urine alkalinization effect of sodium bicarbonate.The second part introduces the mechanism and research status of promising radionuclide decorporation agents.Among them,3,4,3-LI(1,2-HOPO)and 5-LIO(Me-3,2-HOPO)are the most promising ones and have been approved for phase Ⅰ clinical trials.Others such as catecholamines,polyethyleneimine and fullerenes are also being studied with great potential.Polyethyleneimine,as a biological macromolecular chelator,has more chelating sites and stronger targeting effects than small molecule chelators,and has achieved a real breakthrough in decorporation.Fullerenes are known as"free radical sponges"with good free radical scavenging ability and antioxidant properties.In recent years,biomaterials have been widely used in the field of radionuclide decorporation,which has greatly improved the decorporation efficiency.Chitosan and pectin have shown great advantages in promoting radionuclide decorporation,chitosan can adsorb metal ions through electrostatic interaction and chelation,and can also react with free radicals to remove free radicals generated after radionuclides enter the body.Pectin can promote uranium efflux,but the exact mechanism remains unclear.Liposomes and nanomaterials as carriers enhance the intracellular drug delivery,prolong the retention time of drugs in the body,reduce adverse reactions,and make the traditional efflux enhancers glow with new vitality and have good development prospects.The last part summarizes and looks forward to the future research direction of radionuclide decorporation agents.At present,the research on decorporation agents at home and abroad is mostly stuck in the stage of drug development and drug synthesis,and few have actually entered the clinical trial stage.Therefore,the optimization of existing decorporation agents and the development of new ligands are critical.The targeting,biological safety,oral availability,and treatment needs of large-scale contamination scenarios are still the focus of attention.In addition,from the point of view of the mechanism itself,it is a new idea to promote the emission of radionuclides by activating potential channels,which can be continuously explored.
radionuclidesinternal contaminationdecorporation agentsmechanism of action
万方数据
维普
