The influence of soybean diacylglycerol on brain phospholipid synthesis during aging

The synthesis of choline phosphoglycerides and ethanolamine phosphoglycerides has been examined in brain cortex microsomes and neuronal populations of rats during various times of aging as compared to 2 months-old animals. A noticeable decrease of synthesis of both lipid classes takes place in these conditions in vitro. The concentration of the endogenous diacylglycerol is not changed during aging neither in microsomes nor in neurons. The molar distribution of fatty acids in brain microsomal diacylglycerols of aging rats is noticeably different from that of adult animals. The content of monoenoic and dienoic species is increased, whereas that of the tetraenoic species is decreased. The addition of soybean diacylglycerol to microsomes or neuronal preparations from aged rat brain restores practically the decreased synthesizing activity of CPG and partially that of EPG. It is proposed that adding diacylglycerols to aged membranes affects the properties of the membranes and probably enzyme-lipid interactions.