Mechanisms of Anti-Cancer Effects of <i>Vernonia amygdalina</i> Leaf Extract

Abstract

Problem statement: Vernonia amygdalina (V. amygdalina) has been shown to have cancer cell inhibition and cytotoxic effects. Approach: This study discusses the multi-faceted and multilinked mechanisms by which cancer tissue inhibition and destruction is achieved by V. amygdalina leaf extract and powder (subsequently called V. amygdalina Extract). Cancer cell inhibition by V. amygdalina is suggested to occur through inhibition of sterol 14-α-demethylase, a microsomal P450dependent enzyme system) of the membrane of the cancer cell. Inhibition of this enzyme impairs the biosynthesis of ergosterol for the cytoplasmic membrane. Results: This impairment of the synthesis of ergosterol disrupts the close packing of acyl chains of phospholipids and impairs the function of some membrane-bound enzyme systems like ATPase and enzymes of electron-transport system of the cancer cells. V. amygdalina extract inhibits sterol 14-α-demethylase by acting on β 3 adrenergic receptors of the cancer cell membranes as a primary ligand in Gi (inhibitory) receptors on cancer β 3 lipid cell membrane receptors and mitochondrial ATP energy generation system receptors. Conclusion: By effecting β-oxidation of fatty acids and lipids in cell membranes and cell mitochondrial energy (ATP) generation systems, the V. amygdalina extract uncouples the mitochondrial energy (ATP generation) systems of the cancer cells and cell membranes resulting in the cancer cells being burnt out (consumed) by the extract (when V. amygdalina extract is cytotoxic to the cancer cells) or its functioning being inhibited (when V. amygdalina extract is only inhibitory to the cancer cells.