The EPR study of LDL perturbed by alcohols with different molecular architecture

Interaction of alcohols with serum LDL

The interaction of low molecular weight alcohols with low density lipoprotein (LDL) has been studied using amide I band-fitting, thermal profiling and two-dimensional infrared correlation spectroscopy (2D-IR). At 0.3 M alcohol, no changes in secondary structure are observed. In the presence of 1 M alcohol, ethanol and propanol decreases protein denaturation temperature and produces changes in the amide I thermal profiles of protein components and in the lipid bands. The 2D-IR synchronous map corresponding to protein or lipid component at 20-37 degrees C suggests differences in the presence of propanol. The asynchronous map corresponding to the lipid component indicates changes in bandwidth, compatible with a more fluid environment. In the 37-80 degrees C temperature range the thermal profile is different in the presence of propanol, both for the lipid and protein components. The results presented show that when alcohols affect the protein component, the lipid spectrum also varies pointing to an effect on the lipid-protein interaction.

Mechanism of anesthetic action: oxygen pathway perturbation hypothesis

Although more than 150 years have passed since the discovery of general anesthetics, precisely how they work remains a mystery. We propose a novel unitary mechanism of general anesthesia verifiable by experiments. In the proposed mechanism, general anesthetics perturb oxygen pathways in both membranes and oxygen-utilizing proteins, such that the availability of oxygen to its sites of utilization is reduced, which in turn triggers cascading cellular responses through oxygen-sensing mechanisms, resulting in general anesthesia. Despite the general assumption that cell membranes are readily permeable to oxygen, existing publications indicate that these membranes are plausible oxygen-transport barriers. The present hypothesis provides a unified framework for explaining phenomena associated with general anesthesia and experimental results on the actions of general anesthetics. If verified by experiments, the proposed mechanism also has other significant medical and biological implications.