Inhibition of Peroxidase and Catalase Activities and Modulation of Hydrogen Peroxide Level by Inositol Phosphoglycan-like Compounds

Abstract

Inositol phosphoglycan-like compounds are produced by the hydrolysis of the membrane bound glycosyl phosphoinositides. Besides being short term mediators of insulin action, they inhibit peroxidases and catalase, increasing the concentration of cellular hydrogen peroxide. Although high concentrations of hydrogen peroxide are toxic, moderate increases of its basal level are signals for different metabolic pathways. The inhibitor, localized in the cytosol of the cell, acts on peroxidases and catalase of the same tissue (homologous action) and of other tissues or organisms (heterologous action). The inositol phosphoglycan-like compound inhibits peroxidases with different prosthetic groups, i.e. containing iron such as: thyroid peroxidase, lactoperoxidase, horseradish peroxidase, soy bean peroxidase; and containing selenium such as glutathione peroxidase and 2-cys peroxiredoxin with no prosthetic group. Besides peroxidases, the inositol phosphoglycan-like compound inhibits catalase, another heme enzyme. The inhibition kinetics demonstrates a noncompetitive effect. The site of action is not the prosthetic group, given that the inhibitor does not produce any effect on the peak in the Soret region in the presence or absence of hydrogen peroxide. In conclusion, the inositol phosphoglycan-like compound is the general inhibitor of peroxidases and catalase involved in the modulation of hydrogen peroxide level that acts in different metabolic pathways as a signal transducer.

Hydrogen peroxide‐induced translocation of glycolipid‐anchored (c)AMP‐hydrolases to lipid droplets mediates inhibition of lipolysis in rat adipocytes

“…The Nox‐dependent ROS production may be supported by impaired ROS degradation. Interestingly, phosphoinositolglycans prepared from plants and bacteria have been shown to inhibit the peroxidase and haeme‐containing catalase in non‐competitive fashion ( Thomasz et al ., 2007 ). Strikingly, similar phosphoinositolglycan structures may be released from the GPI anchors of GPI‐proteins, such as Gce1 and CD73, upon lipolytic cleavage by the GPI‐PLC ( Stralfors, 1997 ; Jones and Varela‐Nieto, 1998 ), which is apparently activated by palmitate, glimepiride and H 2 O 2 ( Müller et al ., 1993 , 1994a , 2008c ; Movahedi and Hooper, 1997 ; see Figure 4).…”

The effect of ginseng plant on the activity of monoamino oxidase and peroxidase

“…Theses enzymes belong to oxidoreductases class which has different roles in some metabolic pathways of aerobic organisms. They exist in animal and plant tissues as well as in microorganisms, Peroxidases catalyze the oxidation -reduction reaction that occurs between H 2 O 2 and various reductants [21,22] . Hydrogen peroxide is (H 2 O 2 ) a signaling molecule that has an important role in the regulation of many biological processes [23,24] .…”

“…Previous finding reported that Inositol phosphoglycan-like compounds decrease the activity of the two enzymes including peroxidases and catalase, with increasing the concentration of cellular H 2 O 2 . Although high concentrations of H 2 O 2 consider toxic, but slightly increase in H 2 O 2 level is associated to several metabolic pathways [22] .…”