{"id":11,"date":"2008-03-07T11:24:44","date_gmt":"2008-03-07T19:24:44","guid":{"rendered":"http:\/\/blogs.edf.org\/nanotechnology\/2008\/03\/07\/nano-%e2%80%9ctrojan-horse%e2%80%9d-study-gets-top-billing\/"},"modified":"2024-02-12T11:00:20","modified_gmt":"2024-02-12T16:00:20","slug":"nano-trojan-horse-study-gets-top-billing","status":"publish","type":"post","link":"https:\/\/blogs.edf.org\/health\/2008\/03\/07\/nano-trojan-horse-study-gets-top-billing\/","title":{"rendered":"Nano \u201cTrojan Horse\u201d Study Gets Top Billing"},"content":{"rendered":"

<\/em>Cal Baier-Anderson, Ph.D.<\/em>, is a Health Scientist.<\/em><\/p>\n

Each year, the journal Environmental Science & Technology<\/a> selects a list of Top Papers it has published that are \u201cexpected to have a significant and long-lasting impact on the field.\u201d For 2007, its choice for the top environmental science paper<\/a> addresses a curious facet of the behavior of certain metal oxide nanoparticles:\u00a0 They can behave as \u201cTrojan horses,\u201d getting inside cultured lung cells and causing significant damage. <\/p>\n

The paper, \u201cExposure of Engineered Nanoparticles to Human Lung Epithelial Cells: Influence of Chemical Composition and Catalytic Activity on Oxidative Stress<\/a>,\u201d demonstrates that when lung epithelial cells \u2013 the type that line the lungs \u2013 are exposed in culture to various forms of metal oxides, they readily take them up if they are in the form of nanoparticles, but not if they\u2019re dissolved or in the form of larger particles.\u00a0 Once inside the cells, the metals generate reactive oxygen species, such as hydrogen peroxide, which can cause a type of damage called oxidative stress.<\/p>\n

The authors liken this uptake-and-damage mechanism to that of the Trojan horse:\u00a0 The nanoparticles appear to \u201ctrick\u201d the cells to let them in, and once inside, the toxic metals can wreak havoc.\u00a0 Have a look at the nifty picture in the accompanying story<\/a> announcing ES&T\u2019s selection of this paper.\u00a0 By gaining access to the inside of the cell via nanoparticle transport, metal-generated reactive oxygen species reach critical intracellular targets where they can do damage.<\/p>\n

This well-designed study further demonstrates that, while the nano forms of all of the tested metal oxides are preferentially taken up into cultured cells, they differ in their ability to cause oxidative stress.\u00a0 For example, metal oxide nanoparticles containing cobalt and manganese are much more potent triggers of oxidative stress than those containing iron or titanium.<\/p>\n

The major limitation of this study is that it was performed in cell cultures, not in whole animals. \u00a0While useful for uncovering mechanisms of toxicity and developing hypotheses for further testing, such in vitro<\/em> tests do not always perfectly mimic what happens in vivo<\/em>.\u00a0 It remains to be seen, therefore, whether the observed effects are also seen in a whole animal study.<\/p>\n","protected":false},"excerpt":{"rendered":"

Cal Baier-Anderson, Ph.D., is a Health Scientist. Each year, the journal Environmental Science & Technology selects a list of Top Papers it has published that are \u201cexpected to have a significant and long-lasting impact on the field.\u201d For 2007, its choice for the top environmental science paper addresses a curious facet of the behavior of …<\/p>\n","protected":false},"author":101,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[5009],"tags":[39169],"coauthors":[],"class_list":["post-11","post","type-post","status-publish","format-standard","hentry","category-health-science","tag-in-vitro"],"acf":[],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t