May 20, 2022

PolyU develops a revolutionary and highly effective targeted painkiller for osteoarthritis

HONG KONG, September 14, 2021 /PRNewswire/ — Researchers at the Polytechnic University of Hong Kong (PolyU) have developed a breakthrough image-guided nanoparticle-based photothermal treatment for osteoarthritis pain, using the concept of targeted cancer therapy, but instead applied to the protein that initiates pain signaling along the nervous system.

New targeted osteoarthritis pain theranostics, both diagnostic and therapeutic, consist of gold nanorods coated with a two-dimensional nanomaterial, molybdenum disulfide. The coated nanorods are further fused with antibodies against nerve growth factor (NGF), the protein that triggers pain.

Nanorods fused with antibodies allow active and passive targeting on pain generation related to peripheral osteoarthritis. Moreover, by directly binding NGF molecules to photothermal nanoparticles, which can transfer light energy to local heat, NGF protein will be destroyed under heating with near infrared laser.

Professor YANG Mo, Associate Head (Research) of the Department of Biomedical Engineering and principal investigator of the study, said tests on mice suggest that targeted photothermal treatment achieves satisfactory pain relief and improved motor function.

“This is the first time the concept of targeted photothermal therapy for osteoarthritis pain via nanotechnology has been introduced,” Professor Yang said.

“Nanoparticles hold great promise for clinical translation to achieve long-lasting pain relief for days, compared to currently available drugs that can only provide pain relief for hours,” he said. In their experiment with mouse models of osteoarthritis, nanorods with laser stimulation reduced signs of pain for three to four days.

Another principal investigator, Dr WEN Chunyi, Associate Professor of the Department of Biomedical Engineeringreported that dual-pathway pain treatments with antibody-fused nanorods and laser stimulation more effectively reduced the amount of NGF in joint tissues and did not cause damage to surrounding soft tissue or bone.

“A major concern of previous anti-NGF therapy in clinical trials is the development of destructive arthropathy after the use of high doses of anti-NGF antibodies. To address this issue, we developed the targeted theranostic approach to localize and eliminate NGF so that a minimum dose of anti-NGF antibodies is needed,” explained Dr. Wen, adding that only about 1/100 of the therapeutic dose used in previous clinical trials for control of osteoarthritis pain is needed as part of the new approach.

Osteoarthritis is currently diagnosed by physical examination and, if necessary, by X-ray, MRI and arthroscopy. PolyU’s new technique enables a new approach to accurate diagnosis – osteoarthritis pain imaging, as localized nanorods on injured joints can be tracked using photoacoustic imaging – a new non-invasive imaging modality which combines high contrast and good specificity of optical imaging, while providing the high resolution and depth of penetration offered by ultrasound imaging.

The research team chose gold nanorods because of their good photothermal properties and a molybdenum disulfide coating because of its good biocompatibility. Additionally, molybdenum disulfide has good thermal conductivity and water solubility, as well as high near-infrared absorbance, making it a superior contrast agent for photoacoustic imaging that improves the properties photothermal effects of nanorods.

the Lancet The Osteoarthritis Commission has estimated that the disease has affected more than 500 million people worldwide. The World Health Organization also expects the prevalence of osteoarthritis to increase due to the aging of the population and the increase in related factors such as obesity.

Treatment for osteoarthritis focuses on decreasing pain and improving joint movement. However, painkillers are currently off-target and some even involve significant side effects. Meanwhile, total knee replacement is expensive and requires considerable waiting time for surgery in public hospitals.

“Our molecular theranostic treatment, if it becomes clinically available, could offer the prospect of postponing the need for costly joint replacement operations for several years and significantly improving the quality of life of patients with osteoarthritis,” added Dr Wen.

The research results have been published in the prestigious journal ACS Nano by the American Chemical Society and have been reported by Journals Nature Rheumatology.

Media Contact:

Matt Ho
Senior Manager, Communications and Public Affairs
Tel: (852) 3400 2131
Email: [email protected]

Sharon Yu
Manager, Communications and Public Affairs
Tel: (852) 2766 5103
Email: [email protected]


Show original content:

SOURCE The Polytechnic University of Hong Kong