Participation of ATP/ADP antiporter in oleate- and oleate hydroperoxide-induced uncoupling suppressed by GDP and carboxyatractylate

Abstract

In experiments on isolated kidney and liver mitochondria, it is shown that oleate hydroperoxide induces a much smaller increase in the controlled respiration rate and DeltaPsi decrease than the same concentrations of oleate. Palmitate appears to be less efficient than oleate but more efficient than oleate hydroperoxide. In all cases, GDP and CAtr cause some recoupling, CAtr being more effective. Addition of 0.2 mM GDP before CAtr does not prevent further DeltaPsi increase by subsequent CAtr addition. On the other hand, GDP added after CAtr is without any effect. GDP partially prevents the DeltaPsi lowering by ADP at the State 4--State 3 transition if small amounts of CAtr are present. The data are consistent with the suggestion of F. Goglia and V.P. Skulachev (FASEB J. 17, 1585-1591, 2003) that fatty acid anions are translocated by mitochondrial anion carriers much better than their hydroperoxides. As to GDP recoupling, it cannot be regarded as a specific probe for uncoupling by UCPs since it can be mediated by the ATP/ADP antiporter.

Adenine nucleotide translocase family: four isoforms for apoptosis modulation in cancer

“…This supports the hypothesis that ANT participates to a first line of defense against ROS in response to fatty acids, superoxide and lipid peroxidation products under conditions of high oxidative damage (Figure 1) (Scho¨nfeld et al, 1996;Khailova et al, 2006;Azzu et al, 2008;Jastroch et al, 2010;Toime and Brand, 2010). This ANT , 2003).…”

Possible role of avian uncoupling protein in down‐regulating mitochondrial superoxide production in skeletal muscle of fasted chickens

“…In the LDCL method, it should be emphasized that addition of GDP initiated the physical quenching of LDCL according to the amount of GDP in our assay system, so that the specific enhancing of ROS production cannot be detected. However, even though GDP-inhibited proton conductance would be observed more in muscle mitochondria from fasted animals, ANT might still participate in part to this inhibitory effect [48]. Certainly, for avUCP as well as UCP3, much work needs to be done to finalize conclusions concerning the direct uncoupling activity.…”

Fatty Acids Change the Conformation of Uncoupling Protein 1 (UCP1)

“…This increase was almost entirely absent in mitochondria from BAT of Ucp1-null mice (Fig. 2c, right), where trace binding was likely attributable to the adenine nucleotide translocator (32).…”