Finding holds potential for drug targeting to treat diabetes
Schematic represenation of pancreatic islets from Wdr 13 gene intact mouse (left) and Wdr 13 gene knockout mouse (right)
Scientists from the Centre for Cellular and Molecular Biology (CCMB) have found that knocking out a gene in mice led to higher insulin production and better glucose tolerance. The finding holds the potential for drug targeting to treat diabetes.
The team, led by Satish Kumar, serendipitously found that knocking out the WDR13 gene, resulted in hyper insulin secretion and improved glucose clearance. The team genetically engineered a mouse by knocking out the gene, which is conserved in all organisms from fishes to humans and encodes a protein. It is a member of the WD-repeat proteins that have a wide range of cellular functions.
The increase in insulin production was caused by enhanced beta cell proliferation and higher islet mass in pancreas. This gene was knocked out for the first time, said Vijay Pratap Singh, lead author of the study, which was published online in science journal PLoS ONE recently.
The test animals went on to develop mild obesity as they aged. Interestingly, however, they continued to have better glucose clearance in spite of mild obesity. It was not yet known if the obesity was due to higher insulin levels or some different function of the gene.
Dr. Kumar told The Hindu that by inhibiting the functions of this protein, insulin production could be enhanced.
“Indirectly, we discovered a drug target because now we know that if we interfere with this protein, there is more insulin,” he said.
However, he noted that there was a flipside to the finding. While there was no problem with the ‘knockout' mice up to one year, subsequently, their cell proliferation increased — such phenomenon lead to tumours. The researchers were not aware of the WDR13's function of regulating cell division.
The real challenge would be to develop a drug, which would interfere in a limited way with the functioning of the gene, so as to avoid rapid cell proliferation.
Dr. Kumar said their research initially was not related to diabetes. “We were doing basic biology. This is side implication with an interesting lead.”
Describing the finding as a “good and useful observation,” CCMB director Ch. Mohan Rao said: “We are trying to decipher the cause for increase in fatty cells and the pancreatic cells.” There was scope for drug development if the two could be separated.
