Recognition forces involved in mitochondrial binding to a low-affinity trimetazidine binding site related to anti-ischemic activity

Biochem Pharmacol. 2002 May 1;63(9):1691-7. doi: 10.1016/s0006-2952(02)00913-9.

Abstract

A number of heterogeneous drugs previously shown to bind to trimetazidine (TMZ) binding sites on mitochondria and to inhibit mitochondrial swelling (Morin et al., Br J Pharmacol 1998;123:1385-94) were investigated here for their physicochemical properties. The molecular parameters measured were the partition coefficients of the neutral and monocationic forms in the n-octanol/water and dichloroethane/water systems, their distribution coefficients at pH 7.4 in these two solvent systems, as well as their distribution coefficients at pH 7.4 in a phosphatidylcholine (PhC) liposomes/water system (log D(lip)(7.4)). Most of these properties were not correlated with affinity to mitochondria or inhibition of mitochondrial swelling. In contrast, log D(lip)(7.4) showed a modest correlation with binding to the low-affinity site (r(2)=0.52) and a better correlation with anti-swelling activity (r(2)=0.69), itself well correlated with binding to the low-affinity sites (r(2)=0.83). Thus, these sites have recognition properties much like those of membranes, as they depend on lipophilicity-hydrophobicity (core binding) and ionic bonds (surface interactions).

MeSH terms

  • Animals
  • Binding Sites
  • Drug Carriers
  • Ischemia / prevention & control
  • Liposomes
  • Mitochondria / drug effects*
  • Mitochondria / metabolism
  • Mitochondria / physiology
  • Mitochondrial Swelling / drug effects
  • Trimetazidine / pharmacology*
  • Trimetazidine / therapeutic use
  • Vasodilator Agents / pharmacology*
  • Vasodilator Agents / therapeutic use

Substances

  • Drug Carriers
  • Liposomes
  • Vasodilator Agents
  • Trimetazidine