Abstract
Polyamines (PAs), endogenous metabolites with a wide range of biological activities, are synthesized at a high rate in liver supporting hepatocyte proliferation and survival. The liver appears as an important regulator of plasma PAs; however, the perspective to exploit plasma PA measurements as indicators for liver function was not explored. This study aimed to evaluate the value of the plasma levels of PAs as a biomarker of pathological changes in the liver in patients with obstructive cholecystitis. The levels of polyamines and their acetylated forms were measured using HPLC/UV in the plasma of patients with obstructive cholecystitis and in healthy subjects. PA turnover was assessed by the ratio between an acetylated form of PA and PA. An effect of diet preference of cheese or meat, the major exogenous sources of PAs, smoking, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in anamnesis was also evaluated in healthy subjects. We found that the plasma levels of spermine and acetylated spermidine decreased in patients with obstructive cholecystitis without a concurring increase in the total plasma bilirubin and amylase levels. The turnover of spermine and spermidine was also changed, suggesting a decrease in the rate of PA degradation in the liver. In healthy subjects, the PA levels tended to mirror chronic smoking and recent SARS-CoV-2 infection but were not relevant to diet factors. A number of observations indicated the role of physical exercise in the regulation of the plasma pool of PA. The decrease in plasma PA levels and index of PA turnover in the cholestasis syndrome indicate the liver’s metabolic function reduction. A conceivable effect of lung-related conditions on plasma PA, while indicating low specificity, nonetheless, speaks favorably about the high sensitivity of plasma PA measurement as an early diagnostic test in the clinic.