A new research study might create new avenues for comprehending the impact of cholesterol on cell membranes and their receptors, setting the stage for future investigations into diseases associated with membrane organization.
Researchers from Rice University, under the guidance of Jason Hafner, have conducted a study that could significantly enhance our understanding of how cholesterol affects cell membranes and their receptors, paving the way for future research on diseases linked to membrane structure. This study was published in the Journal of Physical Chemistry.
Cholesterol is a crucial molecule found in biomembranes, which are intricate structures made up of proteins and lipids. It plays an essential role in organizing these membranes and in regulating the behavior of receptors located within them. However, gaining insights into the structure and interactions of cholesterol within biomembranes has proven to be a longstanding challenge for scientists.
“Our findings may have important repercussions for understanding conditions associated with cell membrane function, particularly cancer, where membrane organization is vital,” stated Hafner, who is a professor of physics, astronomy, and chemistry.
To overcome this challenge, Hafner’s team employed Raman spectroscopy, a method that uses laser light to scatter molecules and generate intricate vibrational spectra, providing significant molecular insights.
The researchers investigated cholesterol molecules embedded in membranes and compared the observed spectra with those predicted through density functional theory, a technique commonly used in quantum mechanical research.
“This approach enabled us to detect the distinctive vibrations of each molecule, which helped us gain further insights into their structures,” Hafner explained.
The team calculated Raman spectra for 60 distinct cholesterol structures, focusing on the unique fused ring design of cholesterol and its eight-carbon chain. As a result, they noticed that these structures could be categorized based on the extent to which the carbon chain deviated from the plane of the rings, revealing previously unidentified structural variations.
This study represents the first instance in which scientists have directly measured the structures of cholesterol chains in their natural membrane context, according to Hafner.
“We were taken aback to find that all cholesterol molecules within the same category exhibited identical spectra at low frequencies,” Hafner noted. “This discovery simplified our analysis and allowed us to align our experimental data to chart out the cholesterol chain structures in membranes.”
