Polydeoxyribonucleotide Attenuates Carbon Tetrachloride-Induced Acute Liver Injury Through A_2A Receptor-Related...

Background/Objectives: Polydeoxyribonucleotide (PDRN) has anti-inflammatory and tissue-protective properties associated with activation of the adenosine A_2A receptor (A_2AR). Although hepatoprotective actions of PDRN have previously been described, its potential association with high-mobility group box 1 (HMGB1)-related inflammatory responses and hepatic macrophage accumulation during acute liver injury (ALI) is not fully understood. This study examined whether PDRN affects HMGB1- and monocyte chemoattractant protein-1 (MCP-1)-associated responses together with hepatic macrophage accumulation in ALI. Methods: ALI was induced in ICR mice by carbon tetrachloride (CCl₄) administration. PDRN was administered either alone or together with the selective A_2AR antagonist 3,7-dimethyl-1-propargylxanthine (DMPX). Serum levels of aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase were quantified. Histological alterations were evaluated using hematoxylin and eosin staining. Hepatic macrophage accumulation was assessed by F4/80 immunofluorescence staining. Enzyme-linked immunosorbent assays were used to quantify HMGB1, MCP-1, interleukin-10 (IL-10), cyclic adenosine monophosphate (cAMP), and A_2AR. Results: PDRN significantly reduced serum markers of liver injury and attenuated histopathological damage following CCl₄ administration. PDRN treatment also decreased F4/80-positive macrophage accumulation in the hepatic tissue. In addition, PDRN reduced HMGB1 and MCP-1 levels in both the serum and liver tissues while significantly increasing IL-10, cAMP, and A_2AR levels. Conclusions: PDRN attenuated CCl₄-induced ALI and was associated with reduced HMGB1 and MCP-1 levels, decreased hepatic macrophage accumulation, and increased A_2AR/cAMP signaling. These findings suggest that modulation of macrophage-associated inflammatory responses may contribute to the hepatoprotective effects of PDRN.