Background:

Perhexiline maleate, an anti-anginal metabolic modulator, blocks the mitochondrial enzyme carnitine palmitoyltransferase 1 (CPT1) and to a lesser extent CPT2, which triggers causes a shift in myocardial substrate utilization from long chain fatty acids to carbohydrates, leading to the increased glucose and lactate utilization and increased ATP production for the same O2 consumption and consequently improves myocardial efficiency.

CPT1 and CPT2 are mitochondrial enzymes which oxidize long-chain fatty acids in the mitochondria. Additionally, perhexiline maleate is found to suppress the activity of Mammalian target of rapamycin complex 1 (mTORC1) which controls the initiation step of protein synthesis via the phosphorylation of eukaryotic initiation factor 4E-binding proteins and of ribosomal S6 kinases.

In vitro: Perhexiline maleate concentration-dependently and competitively inhibited CPT1 in rat cardiac and hepatic mitochondria, with an IC50 value of 77 and 148 μM, respectively. It was indicated that perhexiline maleate displayed a greater sensitivity of the cardiac than the hepatic enzyme when exhibiting inhibition effect [1]. Perhexiline maleate produced concentration-dependent inhibition of CPT2 activity with an IC50 value of 79 μM [2]. In human breast cancer MCF-7 cells, Perhexiline maleate blocked mTORC1 signaling at 10 μM and elicited autophagy