Back in January, scientists at the University of California had successfully devised micro-robots that could be targeted inside our body to precisely deliver drugs. And, this time around, a collaborative effort from from Colombia University Medical Center (CUMC), Brigham and Women’s Hospital and Harvard Medical School have led to a research scope that can allow drone-like nanoparticles to repair arterial plaque and inflammation. This in turn pertains to a potentially effective prevention mode for atherosclerosis – a condition that often fuels heart attacks and strokes due to the deposition of white blood cells along the artery walls, thus reducing their flexibility.
The researchers tested out their newly contrived nanotechnology on mice with the atherosclerosis condition. To that end, the nanoparticles in question were designed by using biodegradable polymeric building blocks. These were tailored to specially carry anti-inflammatory peptides, and as such the peptides were themselves derived from a natural protein called Annexin A1. As for delivering, the nanoparticles can be directly injected into the bloodstream. Consequently they are to find their way to the artery plaques, and finally get embedded onto them to deliver their payload of drugs. Taking advantage of their seriously small size (which is touted to be 1000-times less than a human hair tip), the nano ‘drones’ can also be retained to block plaque rupture and thrombosis – which ultimately prevents the outcomes of heart attacks and strokes.
The testing phase entailed a period of five weeks of treatment on the selected mice (with advanced atherosclerosis conditions). And, the results were pretty encouraging – with damage to the mouse arteries being substantially healed, while the plaques were safely sustained by mitigating the ruptures. The scientists also observed a few other beneficial effects of the released peptides, including the boosting of collagen (that strengthens the fibrous ambit) and the decline of dead cells in the plaque. The other potential advantage of this type of nanoparticle-oriented treatment is summed up by Dr Ira Tabas, co-senior author, MD, Richard J. Stock Professor of Medicine (Immunology) and professor of pathology & cell biology at CUMC –
Many researchers are trying to develop drugs that prevent heart attacks by tamping down inflammation, but that approach has some downsides. One is that atherosclerosis is a chronic disease, so drugs are taken for years, even decades. An anti-inflammatory drug that is distributed throughout the entire body will also impair the immune system’s ability to fight infection. Using this approach to prevent a heart attack that may never happen may not be worth the risk.
Now of course, the success of the peptile-carrying nano ‘drones’ were only tested in mice – animals who do not actually suffer from heart attacks. But considering that atherosclerosis is arguably the most dangerous health condition for humans (it alone accounts for one out of every four deaths in the US), the technology might just make its mark in the coming years. In that regard, the researchers are still looking forth to a medical system in which such nanoparticles can be administered for just a few years, alongside the conventional treatment scopes.
Lower Image Credit: Ira Tabas/Columbia University Medical Center