A research group from the Department of Medicine LKS, Hong Kong University (HKUMed) has developed (Nanoparticle based drug delivery for TH treatment) thyroid hormone (TH) – nanoparticles embedded in adipose peptide, which selectively deliver TH to adipose tissue. This will promote the treatment of health problems related to obesity and TH by overcoming its negative effects caused by systemic administration. The new findings are published in Nature Communications.
Background
Obesity is a major risk factor for many life-threatening chronic diseases such as diabetes, heart disease; and neurodegenerative diseases. TH is an ancient hormone that can treat obesity and related health problems by increasing energy expenditure.
However, despite intensive research efforts over the past decades, clinical trials have not demonstrated a clear clinical benefit of chronic systemic administration of TH in weight loss in obese individuals. In addition, due to the full expression of TH receptors, systemic administration of TH often results in adverse effects of many aspects, such as tachycardia, heart attack, decreased strength, and osteoporosis.
Skeletal muscle and adipose tissue are thought to be the two main target organs where TH exerts its stimulating effect on metabolic rate and energy expenditure. However, whether selective delivery of TH to adipose tissue is sufficient to induce obesity remains unclear.
Research methodology and results
The research team developed TH-encapsulated nanoparticles modified with an adipose peptide to selectively deliver TH to adipose tissue.
Remarkably, the researchers found that TH delivery of adipose tissue is more powerful than TH therapy in reducing obesity and related metabolic disorders, without adverse effects on other non-adipose tissue. Mechanically, the study found that adiposity-targeted TH therapy can convert “bad” white fat into “good” brown fat, which can burn calories by creating heat, when the TH system cannot causing the “browning” of white fat as a result, suppression of sympathetic nerves.
In addition, the research team made the unexpected discovery that targeted delivery of TH effectively reduces hypercholesterolemia and atherosclerosis, the main risk factors for heart disease and stroke.
The need for research
“This is the first proof of concept showing that nanoparticle-based adipose tissue delivery of TH is an effective and safe drug for obesity and related cardiometabolic disorders. The results solved the long-standing mystery of why TH therapy did not reduce the weight, revising the hope of using this ancient hormone for the treatment of chronic diseases through nanoparticle-based targeted delivery, “Professor Xu Said Aimin. , director of the State Key Laboratory of Pharmaceutical Biotechnology and professor of the Department of Medicine, School of Clinical Medicine, HKUMed.
