Nanomedicine part 2: Targeting the brain
Nanoparticles are too small to be seen with a regular microscope. A nanometer is about one billionth of a meter, and nanomaterials measure between 1 and 100 nanometers. The diameter of a human hair is 60,000 to 80,000nm. Nanotechnology is the development of nanomaterials.
Nanoparticles are poised to change the future of science, engineering and technology, and research is proceeding at a swift pace. To get an idea of how important nanotechnology has become, over 1.5 billion dollars was invested in the 2015 budget for the National Nanotechnology Initiative. The massive U.S. BRAIN Initiative (Brain Research through Advancing Innovative Neurotechnologies) and Europe’s Human Brain Project are heavily funded and underway, but remain controversial due to concerns over feasibility, safety and ethics.
In any case, the responsible application of nanotechnology to medicine boasts hopes for extending the human lifespan and improving quality of life. Some proponents even claim that disease and death could be eliminated in a matter of decades. With mental illness and substance use now leading causes of death in the United States, there is a desperate need to find better ways to prevent and treat these disorders.
Nanomedicine is an exciting combination of nanotechnology and biotechnology. While biotechnology is more the manipulation of biological materials to create useful commercial products, nanomedicine focuses primarily on drugs and drug delivery using both biological and synthetic materials. Other applications of nanomedicine include in vivo imaging and diagnostics, biomaterials and implants. Nanomedicine has lead to promising developments in cancer therapy, organ regeneration and targeted drug delivery.
Nanomedicines are developed by creating tiny molecules designed to deliver specific material to biological tissues so that they have the right size, shape and other characteristics that enable them to reach brain cells. These medicines have the advantage of being able to cross the blood-brain barrier (BBB). The BBB is formed by the walls of the tiny blood vessels that protect the brain from 98 to 100 percent of drugs that act on the central nervous system. The BBB has made the development of effective psychiatric medications historically very difficult, until now.
In their 2013 article published in European Neuropsychopharmacology, Guillaume Fond, M.D., Ph.D., and colleagues systematically reviewed the research on nanopsychiatry. The three main applications they describe included pharmacology, analysis of living beings, and central nervous system modeling. Though the authors were somewhat pessimistic about practical applications becoming available in the near future, other researchers continue to make progress.
The development of new drugs and drug delivery systems using nanotechnology is still in its infancy. So far, preliminary work shows little toxicity and high efficiency in organic and synthetic microparticles that deliver psychiatric medications. Antipsychotic nanomedicines include paliperidone palmitate micelles and risperidone polymeric nanoparticles are some examples of synthetic drug delivery systems that are in development.
Nancy J. Woolf, Ph.D., at UCLA is creating artificial neurotransmitters for Alzheimer’s patients by modifying microtubules inside neurons to alter the information transmitted to the brain. Because depression, anxiety and other mental disorders are currently viewed in terms of neurotransmitter imbalances, perhaps in the future there may be a role for artificial neurotransmitters in the treatment of mental illness as well.
Studies investigating vaccines and other nanotechnologies to prevent and treat addiction are currently in the pre-clinical stages of development. Despite promising results, scientists are having trouble securing funding for addiction vaccine research. This subject will be discussed further in part 3 of this series.
Analysis of living beings
In vivo imaging and diagnostics refer to nanoparticles introduced into a human or animal body to provide enhanced diagnosis. These include contrast agents for imaging, such as with MRI, or sensors that detect levels of whatever they are programmed to measure. Nanotechnology has been used to analyze gene expression, precise detection of drug toxicity and other biometrics.
Central nervous system modeling
Here is where the artificial intelligence (AI) part comes in. Inorganic synapses, cortical neural networks, central nervous system models and complex neuromorphic systems are a few terms used to describe AI. Nano-neurostimulation, neural nanorepairs, “neural lace” and “smart dust” are a few more. Those on both sides of the debate over merging humans with technology may use terms like “transhumanism” or “singularity.”
But central nervous system modeling basically involves creating a model of the human brain using DNA and technology to better understand how the brain works and how to fix it when it doesn’t. While scientists have not yet merged man and machine, some breakthroughs have emerged that may help the field of psychiatry. For example, cerebral implants or brain microchips are being tested to treat depression and chronic pain. But again, such treatments remain controversial for obvious reasons.
While a cure for mental illness and substance use disorders is urgently needed in the United States today, it is also essential to ensure that any nanomedical techniques are a) safe, b) effective, c) ethical, d) not misused and e) not exploited. Then responsible application of these technologies may lead to better ways to prevent, diagnose, and treat neurological and behavioral disorders which would dramatically change the world for the better.
The Sovereign Health Group treats individuals with mental illness, substance use disorders and dual diagnosis. We use multimodal diagnostic assessment and treatment to provide optimal long-term outcomes. Comprehensive treatment and ongoing aftercare provide the support patients need to recover from addiction and all of its consequences. To find out more about specialized programs at Sovereign Health, please call us at our 24/7 helpline.
About the author
Dana Connolly, Ph.D., is a senior staff writer for the Sovereign Health Group, where she translates current research into practical information. She earned her Ph.D. in research and theory development from New York University and has decades of experience in clinical care, medical research and health education. The Sovereign Health Group is a health information resource and Dr. Connolly helps to ensure excellence in our model. For more information and other inquiries about this article, contact the author at firstname.lastname@example.org.
Previous blog in the series: http://www.sovhealth.com/advocacy/nanomedicine-part-1-new-drug-delivery-systems/
Next blog in the series: http://www.sovhealth.com/advocacy/nanomedicine-part-3-addiction-vaccination/