The way the cells in bodies handle molecules linked to fats could hold clues to conditions such as obesity and diabetes. Researchers at IIT Hyderabad have shown how a tiny channel in the cell membrane controls the movement of glycerol, a molecule involved in the process of the body handling fats
The study by Dr Himanshu Joshi and doctoral researcher Kunal Rai examined human aquaporin-10, or hAQP10, a protein that allows water and glycerol to pass through the cell membrane. Using computer simulations, the researchers tracked the molecules as they moved through the microscopic channel. They found that glycerol moves much more slowly than water because it encounters narrow points inside the channel where it interacts with the protein
The findings have been published in PNAS, Proceedings of the National Academy of Sciences, said to be one of the world’s most-cited and comprehensive multidisciplinary scientific research journals
The researchers found that glycerol has to reorient itself to get past these molecular checkpoints, while the channel undergoes small local structural changes that help it continue moving. Water, meanwhile, passes through much more easily, facing about four times lower energetic resistance. “This selective slowing of glycerol” helps explain how hAQP10 controls the movement of the molecule, according to the researchers’ findings
That matters because glycerol is involved in lipid metabolism — the way cells handle fats. Understanding how it moves through hAQP10 could therefore help scientists study conditions associated with problems in the channel, including obesity, diabetes and some skin disorders. The study also provides one of the first quantitative estimates of glycerol permeability through a single aquaporin channel, giving future experimental studies a reference point
The research is still at the basic-science stage and does not offer a treatment for these conditions. Its significance lies in showing, at a microscopic level, how cells can control different molecules differently, allowing water through easily while making a fat-related molecule slow down and adjust its path
