Functional consequences of piceatannol binding to glyceraldehyde-3-phosphate dehydrogenase

Abstract

Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) is one of the key redox-sensitive proteins whose activity is largely affected by oxidative modifications at its highly reactive cysteine residue in the enzyme’s active site (Cys149). Prolonged exposure to oxidative stress may cause, inter alia, the formation of intermolecular disulfide bonds leading to accumulation of GAPDH aggregates and ultimately to cell death. Recently these anomalies have been linked with the pathogenesis of Alzheimer’s disease. Novel evidences indicate that low molecular compounds may be effective inhibitors potentially preventing the GAPDH translocation to the nucleus, and inhibiting or slowing down its aggregation and oligomerization. Therefore, we decided to establish the ability of naturally occurring compound, piceatannol, to interact with GAPDH and to reveal its effect on functional properties and selected parameters of the dehydrogenase structure. The obtained data revealed that piceatannol binds to GAPDH. The ITC analysis indicated that one molecule of the tetrameric enzyme may bind up to 8 molecules of polyphenol (7.3 ± 0.9). Potential binding sites of piceatannol to the GAPDH molecule were analyzed using the Ligand Fit algorithm. Conducted analysis detected 11 ligand binding positions. We indicated that piceatannol decreases GAPDH activity. Detailed analysis allowed us to presume that this effect is due to piceatannol ability to assemble a covalent binding with nucleophilic cysteine residue (Cys149) which is directly involved in the catalytic reaction. Consequently, our studies strongly indicate that piceatannol would be an exceptional inhibitor thanks to its ability to break the aforementioned pathologic disulfide linkage, and therefore to inhibit GAPDH aggregation. We demonstrated that by binding with GAPDH piceatannol blocks cysteine residue and counteracts its oxidative modifications, that induce oligomerization and GAPDH aggregation.

Covalent inhibitors of GAPDH: From unspecific warheads to selective compounds

“…Indeed, the reaction of quinones with thiols is kinetically favored with respect to amines. 174 Many quinone compounds are coming from the oxidative metabolism or autoxidation of catechol and hydroquinone endogenous compounds, 175,176 natural molecules [177][178][179][180] and xenobiotics 181 . Their phenolic form, after converting to quinone, becomes capable of reactivity towards Cys residues of GAPDH, often unspecifically.…”

The Dietary Antioxidant Piceatannol Inhibits Adipogenesis of Human Adipose Mesenchymal Stem Cells and Limits Glucose Transport and Lipogenic Activities in Adipocytes

“…Piceatannol was recently proposed to inhibit glyceraldehyde 3-phosphate dehydrogenase (GAPDH), the enzyme catalyzing the 6th step of glycolysis, and known to exert many other functions. It is the piceatannol capacity to interact with the highly reactive cysteine residue in the enzyme’s active site that prompted the authors to propose a redox-sensitive inhibition [ 24 ]. However, this GAPDH enzyme is not the same as the glycerol-3-phosphate dehydrogenase (GPDH), which catalyzes the reversible conversion between dihydroxyacetone phosphate and glycerol 3-phosphate.…”

The Writers, Readers and Erasers in Redox Regulation of GAPDH

“…In contrast, the naturally occurring compound piceatannol was reported to prevent both nuclear translocation and aggregation of GAPDH [156]. Piceatannol was demonstrated to covalently bind the catalytic cysteine of GAPDH and preclude GAPDH nuclear translocation and apoptosis in cells exposed to oxidative stress, while also preventing formation of intermolecular disulfide bonds and associated GAPDH aggregation [156]. Several small molecule compounds of plant origin have been recently shown to inhibit oxidative stress-induced GAPDH aggregation [157], by binding to the NAD + -binding site of GAPDH.…”