BUFFALO, N.Y. -- In the images of fruit flies, clusters of
neurons are all lit up, forming a brightly glowing network of
highways within the brain.
It's exactly what University at Buffalo researcher Shermali
Gunawardena was hoping to see: It meant that ORMOSIL, a novel class
of nanoparticles, had successfully penetrated the insects' brains.
And even after long-term exposure, the cells and the flies
themselves remained unharmed.
The particles, which are tagged with fluorescent proteins, hold
promise as a potential vehicle for drug delivery.
Each particle is a vessel, containing cavities that scientists
could potentially fill with helpful chemical compounds or gene
therapies to send to different parts of the human body. Gunawardena
is particularly interested in using ORMOSIL -- organically modified
silica -- to target problems within neurons that may be related to
neurodegenerative disorders including Alzheimer's disease.
The recent study on fruit flies is a step toward making this
happen, demonstrating that long-term exposure to ORMOSIL, through
breathing and feeding, did not injure the animals.
The research appeared in the journal PLoS ONE on Jan. 3.
"We saw that after feeding these nanoparticles in the fruit fly
larvae, the ORMOSIL was going mainly into the guts and skin. But
over time, in adult flies, you could see it in the brain. These
results are really fascinating because these particles do not show
any toxic effects on the whole organism or the neuronal cells,"
said Gunawardena, an assistant professor of biological sciences and
a researcher in UB's Institute for Lasers, Photonics and
The ORMOSIL particles she is investigating are a unique variety
crafted by a research group led by Paras N. Prasad, the UB
institute's executive director. Each particle contains cavities
that can hold drugs, which can be released when the particles are
exposed to light.
Besides Gunawardena and Prasad, co-authors on the study include
Farda Barandeh, Phuong-Lan Nguyen, Rajiv Kumar, Gary J. Iacobucci,
Michelle L. Kuznicki, Andrew Kosterman and Earl J. Bergey, all from
Gunawardena is an expert in axonal transport. This involves the
movement of motor proteins along neurons' thread-like axon. These
molecular motors, called kinesins and dyneins, carry "cargo"
including vital proteins to and from the synapse and cell body of
In this neuronal highway system, one problem that can occur is
an axonal blockage, which resembles a traffic jam in neurons.
Proteins aggregate in a clump along the axon. (For videos showing
both a normal axonal pathway and a blocked pathway, visit http://biology.buffalo.edu/Faculty/Gunawardena/gunawardena_lab/research.html.
Researchers don't know whether these obstructions contribute to
disorders such as Alzheimer's or Parkinson's diseases, which are
characterized by unusual build-ups of proteins called amyloids and
But the amyloid precursor protein involved in Alzheimer's
disease has been shown to have a role in axonal transport, and if
axonal obstructions do turn out to be an early indicator for
neurodegeneration seen in Alzheimer's disease, eliminating
blockages could help prevent or delay the onset of disease.
That's where ORMOSIL comes in: Gunawardena hopes to use these
nanoparticles to target drugs to protein jams along axons, breaking
up the accumulations.
Success, if possible, is still a long way off. But the potential
benefit is great. Gunawardena calls the research a "high-risk,
The next step is for her team to see if they can find a way to
force the ORMOSIL to latch onto motor proteins. (The nanoparticles,
on their own, do not move along axons.)
The University at Buffalo is a premier research-intensive public
university, a flagship institution in the State University of New
York system and its largest and most comprehensive campus. UB's
more than 28,000 students pursue their academic interests through
more than 300 undergraduate, graduate and professional degree
programs. Founded in 1846, the University at Buffalo is a member of
the Association of American Universities.