Certain aspects of uncoupling due to mitochondrial uncoupling proteins in vitro and in vivo.
Thermogenic uncoupling has been proven only for UCP1 in brown adipose tissue. All other isoforms of UCPs are potentially acting in suppression of mitochondrial reactive oxygen species (ROS) production. In this contribution we show that BAT mitochondria can be uncoupled by lauric acid in the range of approximately 100 nM when endogenous fatty acids are combusted by carnitine cycle and beta-oxidation is properly separated from the uncoupling effect. Respiration increased up to 3 times when related to the lowest fatty acid content (BSA present plus carnitine cycle). We also illustrated that any effect leading to more coupled states leads to enhanced H2O2 generation and any effect resulting in uncoupling gives reduced H2O2 generation in BAT mitochondria. Finally, we report doubling of plant UCP transcript in cells as well as amount of protein detected by 3H-GTP-binding sites in mitochondria of shoots and roots of maize seedlings subjected to the salt stress.
Dlasková
Andrea
A
Department No.75, Membrane Transport Biophysics, Institute of Physiology, Academy of Sciences of the Czech Republic, Vídenská 1083, 14220 Prague 4, Czech Republic.
Spacek
Tomás
T
Skobisová
Eva
E
Santorová
Jitka
J
Jezek
Petr
P
D002001:Adipose Tissue, Brown / Q000378:metabolism*; D000818:Animals; D001665:Binding Sites; D002331:Carnitine / Q000378:metabolism; D002352:Carrier Proteins / Q000502:physiology*; D019069:Cell Respiration; D005227:Fatty Acids / Q000378:metabolism*; D006160:Guanosine Triphosphate / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000378:metabolism; D066298:In Vitro Techniques; D007473:Ion Channels; D007850:Lauric Acids / Q000378:metabolism / Q000494:pharmacology; D008322:Mammals; D008565:Membrane Proteins / Q000502:physiology*; D008928:Mitochondria / Q000378:metabolism*; D024101:Mitochondrial Proteins; D018384:Oxidative Stress; D010940:Plant Proteins / Q000502:physiology; D018517:Plant Roots / Q000378:metabolism; D018520:Plant Shoots / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D014475:Uncoupling Agents / Q000378:metabolism / Q000494:pharmacology; D000071256:Uncoupling Protein 1; D003313:Zea mays / Q000378:metabolism
D002352:Carrier Proteins; D005227:Fatty Acids; D007473:Ion Channels; D007850:Lauric Acids; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D010940:Plant Proteins; D017382:Reactive Oxygen Species; D014475:Uncoupling Agents; D000071256:Uncoupling Protein 1; C030358:lauric acid; D006160:Guanosine Triphosphate; D006861:Hydrogen Peroxide; D002331:Carnitine