Opportunities of high-technology phenotyping by the NMR spectroscopy method by example of the metabolic response of the rat liver to the effect of alcohol and Reishi

Abstract

The metabolic profiling of the rat liver was carried out in order to estimate the efficiency of proton nuclear magnetic resonance ( 1 H NMR) spectroscopy as a method of metabolomic phenotyping and a method of detecting early metabolic changes during toxic effects. The tissue samples were taken from three groups of rats: group C, control animals; group A, animals that repeatedly received 15% alcohol solution (its intake induced no pathological liver changes, but stimulated the proliferation of the hepatocytes); and group A + R, alcohol in combination with the plant hepatoprotective Reishi preparation (Ganoderma lucidum). As follows from the results obtained, the changes in the metabolite concentration in liver (observed in group A) reflected the typical metabolic reaction to the alcohol intake and were expressed in a decrease in the content of glycine, leucine, isoleucine, valine, choline, and lactate, as well as in an increase in the TMAO level. The concentration of glycine, valine, and TMAO was restored in the rats of group A + R during the Reishi intake. In addition, an increase in the concentrations of NAD, ATP, UTP, succinate, pyranose, and acetate was registered in group A + R relative to the control. Individual variations in the content of valine, isoleucine, leucine, lactate, choline, and pyranose is correlated to the number of binuclear hepatocytes (as an indicator of proliferative activity). Thus, the study of liver tissues by 1 H NMR spectroscopy method allows us to detect early deviations in the level of metabolites during chronic consumption of small alcohol doses and can be a promising approach both for diagnostic detection of alcoholic liver damage and for estimation of the efficiency of the applied drug therapy.

In Vitro 1H NMR Metabolic Profiles of Liver, Brain, and Serum in Rats After Chronic Consumption of Alcohol

“…Lactate (p < 0.001, Table 1) levels were statistically smaller in serum samples in the alcohol group than in the control group but not in the liver, which differs from the results of our previous study [15]. Lactate is synthesized primarily from pyruvate in glycolysis and transforms into pyruvate via gluconeogenesis.…”

“…Hydrophobic and hydrophilic metabolites were separated using a chloroform-water mixture (1:1 by volume) followed by dehydration of the hydrophilic part over 12 h (CentriVap Solvent Concentrator Systems, Labconco, USA). The detailed protocol was published previously [15], and the necessity of the steps to be performed was also described earlier [17,18]. Serum samples were removed from the freezer and thawed at room temperature (21 °C, 5 min).…”

“…In our earlier work [15], we evaluated the impact of a low alcohol dose (2-3 g/ kg) only on rat's liver. The alcohol consumption stimulated the proliferation of hepatocytes and changed the concentrations in the range of metabolites (e.g., leucine, valine, choline, etc.).…”