激情快播 researchers have created unique technology for treating osteoporosis that uses nanobubbles to deliver treatment to targeted areas of a person鈥檚 body.
The new technology was developed by Mehdi Razavi, an assistant professor in 激情快播鈥檚 and a member of the Biionix Cluster at 激情快播, and 激情快播 biomedical sciences student Angela Shar at the , as part of the lab鈥檚 focus on developing tools for diagnostics and therapeutics.
Osteoporosis is a disease marked by an imbalance between the body鈥檚 ability to form new bone tissue, or ossification, and break down, or remove, old bone, known as resorption.
According to the Bone Health & Osteoporosis Foundation (BHOF), studies suggest that one in two women and up to one in four men aged 50 and older will break a bone due to osteoporosis. Also, experts predict that by 2025, osteoporosis will be responsible for about 3 million fractures and $25.3 billion in costs annually.
Razavi says that a healthy body continually replaces old or damaged bone tissue at a steady rate to ensure good bone quality and mass.
鈥淏ut when the rate of bone resorption becomes higher than bone formation, then it leads to osteoporosis, a systemic disease of the skeletal system,鈥� he says.
Many osteoporosis treatments today use drugs such as bisphosphonates to inhibit bone resorption. Side effects can include jaw osteonecrosis (delayed healing of the jawbone) and gastrointestinal problems.
The 激情快播 invention, however, uses ultrasound-responsive nanobubbles to deliver treatment to targeted areas of a person鈥檚 body.
鈥淭here are a lot of nanoplatforms out there for osteoporosis treatment,鈥� Razavi says. 鈥淏ut the advantage of ultrasound-responsive nanobubbles is that they require ultrasound for bubble disruption and gene delivery. Ultrasound itself can actually facilitate bone formation.鈥�
A viable, safe alternative, the 激情快播 invention both treats and prevents the effects of osteoporosis.
鈥淚t is a dual-acting technology,鈥� Razavi says. 鈥淥n one side, you are reducing bone resorption, and on the other side, you are increasing bone formation using ultrasound.鈥�
In one example application, the nanobubbles carry the osteoporosis-related silencing or knockdown gene, cathepsin K small interfering ribonucleic acid (CTSK siRNA).
Razavi says that the nanobubbles both protect the siRNA from directly interacting with its surroundings and targets osteoclast cells, which are the bone cells that carry the CTSK gene. CTSK is a key player in the bone resorption process.
鈥淪o, we downregulate, reduce high expression of those [bone resorption] genes using the siRNA,鈥� he says.
He added that the delivery system also helps to slow the release of the treatment and prolong the gene silencing mechanism鈥檚 effectiveness.
Each nanobubble encapsulates the treatment in a gas core and liquid shell made from perfluorocarbon.
鈥淭he gas core helps us to image and track the nanobubbles,鈥� Razavi says. 鈥淚t鈥檚 also embedded with molecules that can target bone.鈥�
鈥淭he bubbles go into the bone cells, search and find those genes that cause osteoporosis, and they bury the CTSK siRNA which then creates a complex,鈥� he says. 鈥淭hat complex is thermodynamically unstable, and that will lead to a kind of downregulation or silencing of those genes. When you measure for cathepsin K expression, you get a lower expression of that.鈥�
For controlled, sequential release and customized treatment (for example, low intensity for superficial fractures versus high intensity for deep lesions) the ultrasound parameters can be modified, including exposure time, intensity, frequency, and waveform.
Razavi cited other uses for the invention.
鈥淵ou can use this for cancer and other applications, like neurodegenerative diseases such as Alzheimer鈥檚,鈥� he says.
One advantage of nanobubbles over microbubbles is their ability to pass through the cell membrane to deliver therapeutics.
鈥淯ltrasound can actually open up the blood-brain barrier to facilitate the migration of the nanobubbles into the neural cells for gene delivery,鈥� he says.
Chemo-therapeutic drugs can be encapsulated into the bubbles and then injected to target tumors. Also, because these bubbles have a gas core, they can deliver oxygen.
鈥淥ne solution here is to deliver oxygen into the tissue to facilitate regeneration,鈥� he says. 鈥淲e are trying to find approaches that could be globally deployed, are non-invasive, widely available, portable, and inexpensive.鈥�
The technology is available for license. For more information about the invention, see the .
Publications
A novel ultrasound-mediated nanodroplet-based gene delivery system for osteoporosis treatment, Nanomedicine. 2022 Apr;41:102530. doi: 10.1016/j.nano.2022.102530. Epub 2022 Jan 30. PMID: 35104672.
