Obesity start-up Adipogen wins VC funding boost

Brisbane biomedical company Adipogen has received a new injection of venture capital to pursue a novel therapy for obesity that would involve blocking the proliferation of fat-storage cells, or adipocytes.

Added to a $234,700 grant already received from AusIndustry's Biotechnology Innovation Fund, the injections bring Adipogen's research funding pool to more than $0.75 million.

The VC injection was led by the dedicated pre-seed fund UniSeed, a joint venture between Melbourne University Private and University of Queensland Holdings, with support from the Queensland government's BioStart program. UniSeed is a partner in Adipogen, with UniQuest and the Queensland Institute of Medical Research.

Adipogen's chief scientific officer, Prof John Prins, whose research group at Brisbane's Princess Alexandra Hospital (PAH) discovered the growth factor's role in regulating adipocyte proliferation, said in vitro tests had already indicated that antagonist compounds can block adipocyte proliferation.

Prins, director of the hospital's Department of Diabetes and Endocrinology, said that while the search for new obesity treatments was highly competitive, the complexity of the body's energy-balance systems provided opportunities for companies like Adipogen to be successful.

The company's approach is based on observations that a reduction in the body's fat mass -- whether achieved by surgical methods such as liposuction, or diet and exercise -- reduce the body's tendency to store fat.

A reduction in the adipocyte population results in increased levels of adiponectin, a signalling molecule with a key role in regulating the balance between muscle and fat -- overweight people produce lower levels of adiponectin, so they tend to produce more adipocytes and become even fatter.

By blocking the signal that causes adipocytes to proliferate, an antagonist could cause people to lose weight by increasing their levels of adiponectin.

Prins said early hopes obese humans could be treated with supraphysiological doses of natural appetite-suppressant leptin had not been realised, and therapies that target the adiponectin pathway may be a better option.

Leptin, secreted by adipocytes, switches off the brain's appetite-control centre in the hypothalamus, but only a tiny minority of obese humans suffer from lack of leptin, or defective leptin receptors. Prins, while working at Cambridge University in the US, studied two such individuals, who lost weight when treated with leptin.

Most obese humans are actually resistant to leptin, and have high levels of leptin in their serum, but supraphysiological doses of leptin have virtually no effect and can actually induce Type 2 diabetes.

Adipogen researchers hope to develop effective antagonists of the growth hormone that causes adipocytes to proliferate, and test them in animal models of human obesity.

Obesity is a major cause of premature mortality and morbidity due to cardiovascular disease, stroke, non-insulin dependent diabetes, cancer and depression in Western nations. The 2000 AUSDIAB study showed 47 per cent of adult Australians are overweight, and 20 per cent are clinically obese.

"Ultimately, we envisage that our lead molecules may become mainstream preventatives and treatments for obesity, providing profound benefits to the health of the Australian and international population and major savings in the cost of healthcare," said Adipogen director Dr Peter Devine.