Inhibition and Characterization of Polyamine Oxidase (Pao) Which Purified from Atherosclerosis Patients

Abstract

Plants are an important source of drugs, and their use in medicine has a long history. Terminalia bellirica Roxb. is a plant that is widely used to treat a variety of ailments, including cardiovascular disease and diabetes. The purpose of this study is to examine the inhibitory effect of petroleum ether and ethyl acetate extracts of T. bellirica seeds on purified polyamine oxidase from atherosclerosis patients. Polyamine oxidases play an essential role in maintaining the polyamine balance in vertebrates to ensure the viability of cellular life.Polyamine oxidases oxidize free and acetylated polyamine compounds as substrate. The effectiveness varies according to the tissue present, and the products of the enzymatic reaction depend on the source of the enzyme.

The research included partially purification of Polyamine oxidases from red blood cells hemolysate atherosclerotic patients, using ammonium sulfate sedimentation, dialysis, ion-exchange chromatography, and finally Sodium dodecyl sulfate-electrophoresis migration. Two isoenzymes of polyamine oxidase (I, II) activitieswere obtained with specific activities of (0.148 and 0.163 x10^-3) Unit\mg protein and molecular weights of 101.9 and 94.2 kilodaltons respectively.Optimum conditions enzyme activity was obtained at 125 microliters of the enzyme, phosphate buffer solution at pH 7.2, temperature 37°C, incubation time 10 min., 125mM of spermine as substrate concentration, and with potassium ion as an activator. A high specificity toward the polyamine, spermine compared to mono and di-amine compounds. The existence of flavine adenine dinucleotide was detected for all isoenzymes. Polyamine oxidase (II) activity was non-competitively inhibited by ethyl acetate and petroleum ether T. bellerica extracts. The Michaelis-Menten constantvalue was unchanged at 0.016mM for control and with two extracts. And the maximum velocity values without extracts were 0.024 U/ml, However, ethyl acetate and petroleum ether extracts were 0.014 and 0.011 U/ml respectively.