TB Bacteria May Have Key To Preventing Diabetes

Main Category: Tuberculosis
Also Included In: Diabetes
Article Date: 04 Jan 2004 - 0:00 PDT


Scientists in Australia are investigating whether the bacteria responsible for tuberculosis (TB) could prevent childhood diabetes. Childhood diabetes, also known as insulin-dependent and type one diabetes, occurs when the body's immune system attacks its own insulin-producing cells in the pancreas.

James Cook University Comparative Genomics Centre head Alan Baxter has disclosed his research suggests a link between diabetes and the lack of exposure to bacterial infections.

'If the immune system is busy fighting other infections it tends not to cause the tissue damage associated with diseases like diabetes,' he said.

'It's like a teenager at the movies - if it's a good movie they stay occupied but if it's not, they get bored and start cutting up the seats.'

Experiments exposing diabetes-prone mice to Mycobacterium bovis, the cattle TB found in unpasteurised milk, found they did not develop the disease. Dr Baxter said his Townsville-based Australian research unit had isolated a molecule of the bacteria which could be administered without causing other diseases.

A phase one trial on humans by the Centenary Institute in Sydney is scheduled for mid-2004, although a second trial will be needed before scientists can describe it as a breakthrough.

'We've taken the bacteria used for the TB vaccine, grown enormous amounts, crushed them and then isolated one molecule,' Dr Baxter said. 'It's that molecule we will be administering.

'Instead of using live bacteria, we're injecting a small amount of killed bacteria ... by not using live bacteria, even if someone has got HIV they won't get infected.' Dr Baxter said his theory linking diabetes and lack of exposure to bacteria is supported by a rise in type 1 diabetes after World War II.

Since then pasteurized milk and sanitized lifestyles, involving a proliferation of bacteria-fighting cleaning agents, have become the norm. 'The incidence of type one diabetes has doubled every 15 years since the Second World War,' Dr Baxter said.

'Back when people had TB in World War II there was a very low incidence of type one diabetes. 'It's our hypothesis that type one diabetes is related to lack of exposure to bacterial infections, but it's not proven yet ... in the mice, we've certainly proven it.'

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