Uncoupling effect of lauryl sulfate on mitochondria can be mediated by release of bound endogenous fatty acids.
The mechanism of uncoupling by lauryl sulfate (LS) has been studied. The very fact that uncoupling by low concentration of LS (a strong acid) resembles very much that by fatty acids (weak acids) was used as an argument against the fatty acid cycling scheme of uncoupling where protonated fatty acids operate as a protonophore. We have found that rat liver and heart muscle mitochondria can be uncoupled by low (70 microM) LS concentration in a fashion completely arrested by the ATP/ADP antiporter inhibitor carboxyatractylate (CAtr). On the other hand, uncoupling by two-fold higher LS concentration is not sensitive to CAtr. Addition of oleate desensitizes mitochondria to low LS so that addition of bovine serum albumin becomes necessary to recouple mitochondria. The data are accounted for assuming that low LS releases endogenous fatty acids from some mitochondrial depots, and these fatty acids are responsible for uncoupling. As to high LS, it causes a nonspecific (CAtr-insensitive) damage to the mitochondrial membrane.
Simonian
R A
RA
Belozersky Institute of Physico-Chemical Biology and Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, 119992, Russia.
Pustovidko
A V
AV
Vyssokikh
M Iu
MIu
Skulachev
V P
VP
D000244:Adenosine Diphosphate / Q000737:chemistry / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000737:chemistry / Q000378:metabolism; D000818:Animals; D017920:Antiporters / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism; D001278:Atractyloside / Q000031:analogs & derivatives / Q000737:chemistry / Q000494:pharmacology; D005227:Fatty Acids / Q000737:chemistry* / Q000378:metabolism; D008930:Mitochondria, Liver / Q000737:chemistry* / Q000378:metabolism; D051336:Mitochondrial Membranes / Q000737:chemistry* / Q000378:metabolism; D051381:Rats; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry* / Q000494:pharmacology; D013501:Surface-Active Agents / Q000737:chemistry* / Q000494:pharmacology; D014475:Uncoupling Agents / Q000737:chemistry* / Q000494:pharmacology
D017920:Antiporters; D005227:Fatty Acids; D013501:Surface-Active Agents; D014475:Uncoupling Agents; D001278:Atractyloside; D012967:Sodium Dodecyl Sulfate; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; C028913:dodecyl sulfate; C003853:carboxyatractyloside